Search results for: pitch range
Commenced in January 2007
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Paper Count: 6559

Search results for: pitch range

259 Biodegradable Cross-Linked Composite Hydrogels Enriched with Small Molecule for Osteochondral Regeneration

Authors: Elena I. Oprita, Oana Craciunescu, Rodica Tatia, Teodora Ciucan, Reka Barabas, Orsolya Raduly, Anca Oancea

Abstract:

Healing of osteochondral defects requires repair of the damaged articular cartilage, the underlying subchondral bone and the interface between these tissues (the functional calcified layer). For this purpose, developing a single monophasic scaffold that can regenerate two specific lineages (cartilage and bone) becomes a challenge. The aim of this work was to develop variants of biodegradable cross-linked composite hydrogel based on natural polypeptides (gelatin), polysaccharides components (chondroitin-4-sulphate and hyaluronic acid), in a ratio of 2:0.08:0.02 (w/w/w) and mixed with Si-hydroxyapatite (Si-Hap), in two ratios of 1:1 and 2:1 (w/w). Si-Hap was synthesized and characterized as a better alternative to conventional Hap. Subsequently, both composite hydrogel variants were cross-linked with (N, N-(3-dimethylaminopropyl)-N-ethyl carbodiimide (EDC) and enriched with a small bioactive molecule (icariin). The small molecule icariin (Ica) (C33H40O15) is the main active constituent (flavonoid) of Herba epimedium used in traditional Chinese medicine to cure bone- and cartilage-related disorders. Ica enhances osteogenic and chondrogenic differentiation of bone marrow mesenchymal stem cells (BMSCs), facilitates matrix calcification and increases the specific extracellular matrix (ECM) components synthesis by chondrocytes. Afterward, the composite hydrogels were characterized for their physicochemical properties in terms of the enzymatic biodegradation in the presence of type I collagenase and trypsin, the swelling capacity and the degree of crosslinking (TNBS assay). The cumulative release of Ica and real-time concentration were quantified at predetermined periods of time, according to the standard curve of standard Ica, after hydrogels incubation in saline buffer at physiological parameters. The obtained cross-linked composite hydrogels enriched with small-molecule Ica were also characterized for morphology by scanning electron microscopy (SEM). Their cytocompatibility was evaluated according to EN ISO 10993-5:2009 standard for medical device testing. Thus, analyses regarding cell viability (Live/Dead assay), cell proliferation (Neutral Red assay) and cell adhesion to composite hydrogels (SEM) were performed using NCTC clone L929 cell line. The final results showed that both cross-linked composite hydrogel variants enriched with Ica presented optimal physicochemical, structural and biological properties to be used as a natural scaffold able to repair osteochondral defects. The data did not reveal any toxicity of composite hydrogels in NCTC stabilized cell lines within the tested range of concentrations. Moreover, cells were capable of spreading and proliferating on both composite hydrogel surfaces. In conclusion, the designed biodegradable cross-linked composites enriched with Si and Ica are recommended for further testing as natural temporary scaffolds, which can allow cell migration and synthesis of new extracellular matrix within osteochondral defects.

Keywords: composites, gelatin, osteochondral defect, small molecule

Procedia PDF Downloads 151
258 A Patient-Centered Approach to Clinical Trial Development: Real-World Evidence from a Canadian Medical Cannabis Clinic

Authors: Lucile Rapin, Cynthia El Hage, Rihab Gamaoun, Maria-Fernanda Arboleda, Erin Prosk

Abstract:

Introduction: Sante Cannabis (SC), a Canadian group of clinics dedicated to medical cannabis, based in Montreal and in the province of Quebec, has served more than 8000 patients seeking cannabis-based treatment over the past five years. As randomized clinical trials with natural medical cannabis are scarce, real-world evidence offers the opportunity to fill research gaps between scientific evidence and clinical practice. Data on the use of medical cannabis products from SC patients were prospectively collected, leading to a large real-world database on the use of medical cannabis. The aim of this study was to report information on the profiles of both patients and prescribed medical cannabis products at SC clinics, and to assess the safety of medical cannabis among Canadian patients. Methods: This is an observational retrospective study of 1342 adult patients who were authorized with medical cannabis products between October 2017 and September 2019. Information regarding demographic characteristics, therapeutic indications for medical cannabis use, patterns in dosing and dosage form of medical cannabis and adverse effects over one-year follow-up (initial and 4 follow-up (FUP) visits) were collected. Results: 59% of SC patients were female, with a mean age of 56.7 (SD= 15.6, range= (19-97)). Cannabis products were authorized mainly for patients with a diagnosis of chronic pain (68.8% of patients), cancer (6.7%), neurological disorders (5.6%), and mood disorders (5.4 %). At initial visit, a large majority (70%) of patients were authorized exclusively medical cannabis products, 27% were authorized a combination of pharmaceutical cannabinoids and medical cannabis and 3% were prescribed only pharmaceutical cannabinoids. This pattern was recurrent over the one-year follow-up. Overall, oil was the preferred formulation (average over visits 72.5%) followed by a combination of oil and dry (average 19%), other routes of administration accounted for less than 4%. Patients were predominantly prescribed products with a balanced THC:CBD ratio (59%-75% across visits). 28% of patients reported at least one adverse effect (AE) at the 3-month follow-up visit and 12% at the six-month FUP visit. 84.8% of total AEs were mild and transient. No serious AE was reported. Overall, the most common side effects reported were dizziness (11.95% of total AEs), drowsiness (11.4%), dry mouth (5.5%), nausea (4.8%), headaches (4.6%), cough (4.4%), anxiety (4.1%) and euphoria (3.5%). Other adverse effects accounted for less than 3% of total AE. Conclusion: Our results confirm that the primary area of clinical use for medical cannabis is in pain management. Patients in this cohort are largely utilizing plant-based cannabis oil products with a balanced ratio of THC:CBD. Reported adverse effects were mild and included dizziness and drowsiness. This real-world data confirms the tolerable safety profile of medical cannabis and suggests medical indications not yet validated in controlled clinical trials. Such data offers an important opportunity for the investigation of the long-term effects of cannabinoid exposure in real-life conditions. Real-world evidence can be used to direct clinical trial research efforts on specific indications and dosing patterns for product development.

Keywords: medical cannabis, safety, real-world data, Canada

Procedia PDF Downloads 103
257 Wetting Characterization of High Aspect Ratio Nanostructures by Gigahertz Acoustic Reflectometry

Authors: C. Virgilio, J. Carlier, P. Campistron, M. Toubal, P. Garnier, L. Broussous, V. Thomy, B. Nongaillard

Abstract:

Wetting efficiency of microstructures or nanostructures patterned on Si wafers is a real challenge in integrated circuits manufacturing. In fact, bad or non-uniform wetting during wet processes limits chemical reactions and can lead to non-complete etching or cleaning inside the patterns and device defectivity. This issue is more and more important with the transistors size shrinkage and concerns mainly high aspect ratio structures. Deep Trench Isolation (DTI) structures enabling pixels’ isolation in imaging devices are subject to this phenomenon. While low-frequency acoustic reflectometry principle is a well-known method for Non Destructive Test applications, we have recently shown that it is also well suited for nanostructures wetting characterization in a higher frequency range. In this paper, we present a high-frequency acoustic reflectometry characterization of DTI wetting through a confrontation of both experimental and modeling results. The acoustic method proposed is based on the evaluation of the reflection of a longitudinal acoustic wave generated by a 100 µm diameter ZnO piezoelectric transducer sputtered on the silicon wafer backside using MEMS technologies. The transducers have been fabricated to work at 5 GHz corresponding to a wavelength of 1.7 µm in silicon. The DTI studied structures, manufactured on the wafer frontside, are crossing trenches of 200 nm wide and 4 µm deep (aspect ratio of 20) etched into a Si wafer frontside. In that case, the acoustic signal reflection occurs at the bottom and at the top of the DTI enabling its characterization by monitoring the electrical reflection coefficient of the transducer. A Finite Difference Time Domain (FDTD) model has been developed to predict the behavior of the emitted wave. The model shows that the separation of the reflected echoes (top and bottom of the DTI) from different acoustic modes is possible at 5 Ghz. A good correspondence between experimental and theoretical signals is observed. The model enables the identification of the different acoustic modes. The evaluation of DTI wetting is then performed by focusing on the first reflected echo obtained through the reflection at Si bottom interface, where wetting efficiency is crucial. The reflection coefficient is measured with different water / ethanol mixtures (tunable surface tension) deposited on the wafer frontside. Two cases are studied: with and without PFTS hydrophobic treatment. In the untreated surface case, acoustic reflection coefficient values with water show that liquid imbibition is partial. In the treated surface case, the acoustic reflection is total with water (no liquid in DTI). The impalement of the liquid occurs for a specific surface tension but it is still partial for pure ethanol. DTI bottom shape and local pattern collapse of the trenches can explain these incomplete wetting phenomena. This high-frequency acoustic method sensitivity coupled with a FDTD propagative model thus enables the local determination of the wetting state of a liquid on real structures. Partial wetting states for non-hydrophobic surfaces or low surface tension liquids are then detectable with this method.

Keywords: wetting, acoustic reflectometry, gigahertz, semiconductor

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256 Theoretical and Experimental Investigation of Structural, Electrical and Photocatalytic Properties of K₀.₅Na₀.₅NbO₃ Lead- Free Ceramics Prepared via Different Synthesis Routes

Authors: Manish Saha, Manish Kumar Niranjan, Saket Asthana

Abstract:

The K₀.₅Na₀.₅NbO₃ (KNN) system has emerged as one of the most promising lead-free piezoelectric over the years. In this work, we perform a comprehensive investigation of electronic structure, lattice dynamics and dielectric/ferroelectric properties of the room temperature phase of KNN by combining ab-initio DFT-based theoretical analysis and experimental characterization. We assign the symmetry labels to KNN vibrational modes and obtain ab-initio polarized Raman spectra, Infrared (IR) reflectivity, Born-effective charge tensors, oscillator strengths etc. The computed Raman spectrum is found to agree well with the experimental spectrum. In particular, the results suggest that the mode in the range ~840-870 cm-¹ reported in the experimental studies is longitudinal optical (LO) with A_1 symmetry. The Raman mode intensities are calculated for different light polarization set-ups, which suggests the observation of different symmetry modes in different polarization set-ups. The electronic structure of KNN is investigated, and an optical absorption spectrum is obtained. Further, the performances of DFT semi-local, metal-GGA and hybrid exchange-correlations (XC) functionals, in the estimation of KNN band gaps are investigated. The KNN bandgap computed using GGA-1/2 and HSE06 hybrid functional schemes are found to be in excellant agreement with the experimental value. The COHP, electron localization function and Bader charge analysis is also performed to deduce the nature of chemical bonding in the KNN. The solid-state reaction and hydrothermal methods are used to prepare the KNN ceramics, and the effects of grain size on the physical characteristics these ceramics are examined. A comprehensive study on the impact of different synthesis techniques on the structural, electrical, and photocatalytic properties of ferroelectric ceramics KNN. The KNN-S prepared by solid-state method have significantly larger grain size as compared to that for KNN-H prepared by hydrothermal method. Furthermore, the KNN-S is found to exhibit higher dielectric, piezoelectric and ferroelectric properties as compared to KNN-H. On the other hand, the increased photocatalytic activity is observed in KNN-H as compared to KNN-S. As compared to the hydrothermal synthesis, the solid-state synthesis causes an increase in the relative dielectric permittivity (ε^') from 2394 to 3286, remnant polarization (P_r) from 15.38 to 20.41 μC/cm^², planer electromechanical coupling factor (k_p) from 0.19 to 0.28 and piezoelectric coefficient (d_33) from 88 to 125 pC/N. The KNN-S ceramics are also found to have a lower leakage current density, and higher grain resistance than KNN-H ceramic. The enhanced photocatalytic activity of KNN-H is attributed to relatively smaller particle sizes. The KNN-S and KNN-H samples are found to have degradation efficiencies of RhB solution of 20% and 65%, respectively. The experimental study highlights the importance of synthesis methods and how these can be exploited to tailor the dielectric, piezoelectric and photocatalytic properties of KNN. Overall, our study provides several bench-mark important results on KNN that have not been reported so far.

Keywords: lead-free piezoelectric, Raman intensity spectrum, electronic structure, first-principles calculations, solid state synthesis, photocatalysis, hydrothermal synthesis

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255 From Over-Tourism to Over-Mobility: Understanting the Mobility of Incoming City Users in Barcelona

Authors: José Antonio Donaire Benito, Konstantina Zerva

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Historically, cities have been places where people from many nations and cultures have met and settled together, while population flows and density have had a significant impact on urban dynamics. Cities' high density of social, cultural, business offerings, everyday services, and other amenities not intended for tourists draw not only tourists but a wide range of city users as well. With the coordination of city rhythms and the porosity of the community, city users order and frame their urban experience. From one side, recent literature focuses on the shift in urban tourist experience from 'having' a holiday through 'doing' activities to 'becoming' a local by experiencing a part of daily life. On the other hand, there is a debate on the 'touristification of everyday life', where middle and upper class urban dwellers display attitudes and behaviors that are virtually undistinguishable from those of visitors. With the advent of globalization and technological advances, modern society has undergone a radical transformation that has altered mobility patterns within it, blurring the boundaries between tourism and everyday life, work and leisure, and "hosts" and "guests". Additionally, the presence of other 'temporary city' users, such as commuters, digital nomads, second home owners, and migrants, contributes to a more complex transformation of tourist cities. Moving away from this traditional clear distinction between 'hosts' and 'guests', which represents a more static view of tourism, and moving towards a more liquid narrative of mobility, academics on tourism development are embracing the New Mobilities Paradigm. The latter moves beyond the static structures of the modern world and focuses on the ways in which social entities are made up of people, machines, information, and images in a moving system. In light of this fluid interdependence between tourists and guests, a question arises as to whether overtourism, which is considered as the underlying cause of citizens' perception of a lower urban quality of life, is a fair representation of perceived mobility excessiveness, place consumption disruptiveness, and residents displacement. As a representative example of an overtourism narrative, Barcelona was chosen as a study area for this purpose, focusing on the incoming city users to reflect in depth the variety of people who contribute to mobility flows beyond those residents already have. Several statistical data have been analyzed to determine the number of national and international visitors to Barcelona at some point during the day in 2019. Specifically, tracking data gathered from mobile phone users within the city are combined with tourist surveys, urban mobility data, zenithal data capture, and information about the city's attractions. The paper shows that tourists are only a small part of the different incoming city users that daily enter Barcelona; excursionists, commuters, and metropolitans also contribute to a high mobility flow. Based on the diversity of incoming city users and their place consumption, it seems that the city's urban experience is more likely to be impacted by over-mobility tan over-tourism.

Keywords: city users, density, new mobilities paradigm, over-tourism.

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254 Biochemical Effects of Low Dose Dimethyl Sulfoxide on HepG2 Liver Cancer Cell Line

Authors: Esra Sengul, R. G. Aktas, M. E. Sitar, H. Isan

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Hepatocellular carcinoma (HCC) is a hepatocellular tumor commonly found on the surface of the chronic liver. HepG2 is the most commonly used cell type in HCC studies. The main proteins remaining in the blood serum after separation of plasma fibrinogen are albumin and globulin. The fact that the albumin showed hepatocellular damage and reflect the synthesis capacity of the liver was the main reason for our use. Alpha-Fetoprotein (AFP) is an albumin-like structural embryonic globulin found in the embryonic cortex, cord blood, and fetal liver. It has been used as a marker in the follow-up of tumor growth in various malign tumors and in the efficacy of surgical-medical treatments, so it is a good protein to look at with albumins. We have seen the morphological changes of dimethyl sulfoxide (DMSO) on HepG2 and decided to investigate its biochemical effects. We examined the effects of DMSO, which is used in cell cultures, on albumin, AFP and total protein at low doses. Material Method: Cell Culture: Medium was prepared in cell culture using Dulbecco's Modified Eagle Media (DMEM), Fetal Bovine Serum Dulbecco's (FBS), Phosphate Buffered Saline and trypsin maintained at -20 ° C. Fixation of Cells: HepG2 cells, which have been appropriately developed at the end of the first week, were fixed with acetone. We stored our cells in PBS at + 4 ° C until the fixation was completed. Area Calculation: The areas of the cells are calculated in the ImageJ (IJ). Microscope examination: The examination was performed with a Zeiss Inverted Microscope. Daytime photographs were taken at 40x, 100x 200x and 400x. Biochemical Tests: Protein (Total): Serum sample was analyzed by a spectrophotometric method in autoanalyzer. Albumin: Serum sample was analyzed by a spectrophotometric method in autoanalyzer. Alpha-fetoprotein: Serum sample was analyzed by ECLIA method. Results: When liver cancer cells were cultured in medium with 1% DMSO for 4 weeks, a significant difference was observed when compared with the control group. As a result, we have seen that DMSO can be used as an important agent in the treatment of liver cancer. Cell areas were reduced in the DMSO group compared to the control group and the confluency ratio increased. The ability to form spheroids was also significantly higher in the DMSO group. Alpha-fetoprotein was lower than the values of an ordinary liver cancer patient and the total protein amount increased to the reference range of the normal individual. Because the albumin sample was below the specimen value, the numerical results could not be obtained on biochemical examinations. We interpret all these results as making DMSO a caretaking aid. Since each one was not enough alone we used 3 parameters and the results were positive when we refer to the values of a normal healthy individual in parallel. We hope to extend the study further by adding new parameters and genetic analyzes, by increasing the number of samples, and by using DMSO as an adjunct agent in the treatment of liver cancer.

Keywords: hepatocellular carcinoma, HepG2, dimethyl sulfoxide, cell culture, ELISA

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253 Petrogeochemistry of Hornblende-Bearing Gabbro Intrusive, the Greater Caucasus

Authors: Giorgi Chichinadze, David Shengelia, Tamara Tsutsunava, Nikoloz Maisuradze, Giorgi Beridze

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The Jalovchat gabbro intrusive is exposed on the northern and southern slopes of Main Range zone of the Greater Caucasus, on an area about 25km2. It is intruded in Precambrian crystalline schists and amphibolites intensively metamorphose them along the contact zone. The intrusive is represented by hornblende-bearing gabbro, gabbro-norites and norites including thin vein bodies of gabbro-pegmatites, anorthosites and micro-gabbros. Especially should be noted the veins of gabbro-pegmatites with the gigantic (up to 0.5m) hornblende crystals. From this point of view, the Jalovchat gabbroid intrusive is particularly interesting and by its unusual composition has no analog in the Caucasus overall. The comprehensive petrologic and geochemical study of the intrusive was carried out by the authors. The results of investigations are following. Amphiboles correspond to magnesiohastingsite and magnesiohornblende. In hastingsite and hornblende as a result of isovalent isomorphism of Fe2+ by Mg, content of the latter has been increased. By AMF and Na20+K diagrams the intrusive rocks correspond to tholeiitic basalts or to basalts close to it by composition. According to ACM-AMF double diagram the samples distributed in the fields of MORB and alkali cumulates. In TiO2/FeO+Fe2O3, Zr/Y-Zr and Ti-Cr/Ni diagrams and Ti-Cr-Y triangular diagram samples are arranged in the fields of island-arc and mid-oceanic basalts or along the trends reflecting mid-oceanic ridges or island arcs. K2O/TiO2 diagram shows that these rocks belong to normal and enriched MORB type. According to Th/Nb/Y ratio, the Jalovchat intrusive composition corresponds to depleted mantle, but by Sm/Y-Ce/Sm - to the MORB area. Th/Y and Nb/Y ratios coincide with the MORB composition, Th/Yb-Ta/Yb and La/Nb-Ti ratios correspond to N MORB, and Rb/Y and N/Y - to the lower crust formations. Exceptional are Ce/Pb-Ce and Nb/Th-Nb diagrams, showing the area of primitive mantle. Spidergrams are characterized by almost horizontal trend, weakly expressed Eu minimums and by a slight depletion of light REE. Similar are characteristic of typical tholeiit basalts. In comparison to MORB spidergrams, they are characterized by depletion of light REE. Their correlation to the spidergrams of Jalovchat intrusive proves that they are more depleted. The above cited points to the gradual depletion of mantle with the light REE in geological time. The RE and REE diagrams reveal unexpected regularity. In particular, petro-geochemical characteristics of Jalovchat gabbroid intrusive predominantly correspond to MORB, that usually is an anomalous phenomenon, since in ‘ophiolitic’ section magmatic formations represented mainly by gigantic prismatic hornblende-bearing gabbro and gabbro-pegmatite are not indicated. On the basis of petro-mineralogical and petro-geochemical data analysis, the authors consider that the Jalovchat intrusive belongs to the subduction geodynamic type. In the depleted mantle rich in water the MORB rock system has subducted, where the favorable conditions for crystallization of hornblende and especially for its gigantic crystals occurred. It is considered that the Jalovchat intrusive was formed in deep horizons of the Earth’s crust as a result of crystallization of water-bearing Bajocian basalt magma.

Keywords: The Greater Caucasus, gabbro-pegmatite, hornblende-bearing gabbro, petrogenesis

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252 Using Business Simulations and Game-Based Learning for Enterprise Resource Planning Implementation Training

Authors: Carin Chuang, Kuan-Chou Chen

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An Enterprise Resource Planning (ERP) system is an integrated information system that supports the seamless integration of all the business processes of a company. Implementing an ERP system can increase efficiencies and decrease the costs while helping improve productivity. Many organizations including large, medium and small-sized companies have already adopted an ERP system for decades. Although ERP system can bring competitive advantages to organizations, the lack of proper training approach in ERP implementation is still a major concern. Organizations understand the importance of ERP training to adequately prepare managers and users. The low return on investment, however, for the ERP training makes the training difficult for knowledgeable workers to transfer what is learned in training to the jobs at workplace. Inadequate and inefficient ERP training limits the value realization and success of an ERP system. That is the need to call for a profound change and innovation for ERP training in both workplace at industry and the Information Systems (IS) education in academia. The innovated ERP training approach can improve the users’ knowledge in business processes and hands-on skills in mastering ERP system. It also can be instructed as educational material for IS students in universities. The purpose of the study is to examine the use of ERP simulation games via the ERPsim system to train the IS students in learning ERP implementation. The ERPsim is the business simulation game developed by ERPsim Lab at HEC Montréal, and the game is a real-life SAP (Systems Applications and Products) ERP system. The training uses the ERPsim system as the tool for the Internet-based simulation games and is designed as online student competitions during the class. The competitions involve student teams with the facilitation of instructor and put the students’ business skills to the test via intensive simulation games on a real-world SAP ERP system. The teams run the full business cycle of a manufacturing company while interacting with suppliers, vendors, and customers through sending and receiving orders, delivering products and completing the entire cash-to-cash cycle. To learn a range of business skills, student needs to adopt individual business role and make business decisions around the products and business processes. Based on the training experiences learned from rounds of business simulations, the findings show that learners have reduced risk in making mistakes that help learners build self-confidence in problem-solving. In addition, the learners’ reflections from their mistakes can speculate the root causes of the problems and further improve the efficiency of the training. ERP instructors teaching with the innovative approach report significant improvements in student evaluation, learner motivation, attendance, engagement as well as increased learner technology competency. The findings of the study can provide ERP instructors with guidelines to create an effective learning environment and can be transferred to a variety of other educational fields in which trainers are migrating towards a more active learning approach.

Keywords: business simulations, ERP implementation training, ERPsim, game-based learning, instructional strategy, training innovation

Procedia PDF Downloads 113
251 Dynamic Thermomechanical Behavior of Adhesively Bonded Composite Joints

Authors: Sonia Sassi, Mostapha Tarfaoui, Hamza Benyahia

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Composite materials are increasingly being used as a substitute for metallic materials in many technological applications like aeronautics, aerospace, marine and civil engineering applications. For composite materials, the thermomechanical response evolves with the strain rate. The energy balance equation for anisotropic, elastic materials includes heat source terms that govern the conversion of some of the kinetic work into heat. The remainder contributes to the stored energy creating the damage process in the composite material. In this paper, we investigate the bulk thermomechanical behavior of adhesively-bonded composite assemblies to quantitatively asses the temperature rise which accompanies adiabatic deformations. In particular, adhesively bonded joints in glass/vinylester composite material are subjected to in-plane dynamic loads under a range of strain rates. Dynamic thermomechanical behavior of this material is investigated using compression Split Hopkinson Pressure Bars (SHPB) coupled with a high speed infrared camera and a high speed camera to measure in real time the dynamic behavior, the damage kinetic and the temperature variation in the material. The interest of using high speed IR camera is in order to view in real time the evolution of heat dissipation in the material when damage occurs. But, this technique does not produce thermal values in correlation with the stress-strain curves of composite material because of its high time response in comparison with the dynamic test time. For this reason, the authors revisit the application of specific thermocouples placed on the surface of the material to ensure the real thermal measurements under dynamic loading using small thermocouples. Experiments with dynamically loaded material show that the thermocouples record temperatures values with a short typical rise time as a result of the conversion of kinetic work into heat during compression test. This results show that small thermocouples can be used to provide an important complement to other noncontact techniques such as the high speed infrared camera. Significant temperature rise was observed in in-plane compression tests especially under high strain rates. During the tests, it has been noticed that sudden temperature rise occur when macroscopic damage occur. This rise in temperature is linked to the rate of damage. The more serve the damage is, a higher localized temperature is detected. This shows the strong relationship between the occurrence of damage and induced heat dissipation. For the case of the in plane tests, the damage takes place more abruptly as the strain rate is increased. The difference observed in the obtained thermomechanical response in plane compression is explained only by the difference in the damage process being active during the compression tests. In this study, we highlighted the dependence of the thermomechanical response on the strain rate of bonded specimens. The effect of heat dissipation of this material cannot hence be ignored and should be taken into account when defining damage models during impact loading.

Keywords: adhesively-bonded composite joints, damage, dynamic compression tests, energy balance, heat dissipation, SHPB, thermomechanical behavior

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250 Ordered Mesoporous Carbons of Different Morphology for Loading and Controlled Release of Active Pharmaceutical Ingredients

Authors: Aleksander Ejsmont, Aleksandra Galarda, Joanna Goscianska

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Smart porous carriers with defined structure and physicochemical properties are required for releasing the therapeutic drug with precise control of delivery time and location in the body. Due to their non-toxicity, ordered structure, chemical, and thermal stability, mesoporous carbons can be considered as modern carriers for active pharmaceutical ingredients (APIs) whose effectiveness needs frequent dosing algorithms. Such an API-carrier system, if programmed precisely, may stabilize the pharmaceutical and increase its dissolution leading to enhanced bioavailability. The substance conjugated with the material, through its prior adsorption, can later be successfully applied internally to the organism, as well as externally if the API release is feasible under these conditions. In the present study, ordered mesoporous carbons of different morphologies and structures, prepared by hard template method, were applied as carriers in the adsorption and controlled release of active pharmaceutical ingredients. In the first stage, the carbon materials were synthesized and functionalized with carboxylic groups by chemical oxidation using ammonium persulfate solution and then with amine groups. Materials obtained were thoroughly characterized with respect to morphology (scanning electron microscopy), structure (X-ray diffraction, transmission electron microscopy), characteristic functional groups (FT-IR spectroscopy), acid-base nature of surface groups (Boehm titration), parameters of the porous structure (low-temperature nitrogen adsorption) and thermal stability (TG analysis). This was followed by a series of tests of adsorption and release of paracetamol, benzocaine, and losartan potassium. Drug release experiments were performed in the simulated gastric fluid of pH 1.2 and phosphate buffer of pH 7.2 or 6.8 at 37.0 °C. The XRD patterns in the small-angle range and TEM images revealed that functionalization of mesoporous carbons with carboxylic or amine groups leads to the decreased ordering of their structure. Moreover, the modification caused a considerable reduction of the carbon-specific surface area and pore volume, but it simultaneously resulted in changing their acid-base properties. Mesoporous carbon materials exhibit different morphologies, which affect the host-guest interactions during the adsorption process of active pharmaceutical ingredients. All mesoporous carbons show high adsorption capacity towards drugs. The sorption capacity of materials is mainly affected by BET surface area and the structure/size matching between adsorbent and adsorbate. Selected APIs are linked to the surface of carbon materials mainly by hydrogen bonds, van der Waals forces, and electrostatic interactions. The release behavior of API is highly dependent on the physicochemical properties of mesoporous carbons. The release rate of APIs could be regulated by the introduction of functional groups and by changing the pH of the receptor medium. Acknowledgments—This research was supported by the National Science Centre, Poland (project SONATA-12 no: 2016/23/D/NZ7/01347).

Keywords: ordered mesoporous carbons, sorption capacity, drug delivery, carbon nanocarriers

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249 Novel Numerical Technique for Dusty Plasma Dynamics (Yukawa Liquids): Microfluidic and Role of Heat Transport

Authors: Aamir Shahzad, Mao-Gang He

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Currently, dusty plasmas motivated the researchers' widespread interest. Since the last two decades, substantial efforts have been made by the scientific and technological community to investigate the transport properties and their nonlinear behavior of three-dimensional and two-dimensional nonideal complex (dusty plasma) liquids (NICDPLs). Different calculations have been made to sustain and utilize strongly coupled NICDPLs because of their remarkable scientific and industrial applications. Understanding of the thermophysical properties of complex liquids under various conditions is of practical interest in the field of science and technology. The determination of thermal conductivity is also a demanding question for thermophysical researchers, due to some reasons; very few results are offered for this significant property. Lack of information of the thermal conductivity of dense and complex liquids at different parameters related to the industrial developments is a major barrier to quantitative knowledge of the heat flux flow from one medium to another medium or surface. The exact numerical investigation of transport properties of complex liquids is a fundamental research task in the field of thermophysics, as various transport data are closely related with the setup and confirmation of equations of state. A reliable knowledge of transport data is also important for an optimized design of processes and apparatus in various engineering and science fields (thermoelectric devices), and, in particular, the provision of precise data for the parameters of heat, mass, and momentum transport is required. One of the promising computational techniques, the homogenous nonequilibrium molecular dynamics (HNEMD) simulation, is over viewed with a special importance on the application to transport problems of complex liquids. This proposed work is particularly motivated by the FIRST TIME to modify the problem of heat conduction equations leads to polynomial velocity and temperature profiles algorithm for the investigation of transport properties with their nonlinear behaviors in the NICDPLs. The aim of proposed work is to implement a NEMDS algorithm (Poiseuille flow) and to delve the understanding of thermal conductivity behaviors in Yukawa liquids. The Yukawa system is equilibrated through the Gaussian thermostat in order to maintain the constant system temperature (canonical ensemble ≡ NVT)). The output steps will be developed between 3.0×105/ωp and 1.5×105/ωp simulation time steps for the computation of λ data. The HNEMD algorithm shows that the thermal conductivity is dependent on plasma parameters and the minimum value of lmin shifts toward higher G with an increase in k, as expected. New investigations give more reliable simulated data for the plasma conductivity than earlier known simulation data and generally the plasma λ0 by 2%-20%, depending on Γ and κ. It has been shown that the obtained results at normalized force field are in satisfactory agreement with various earlier simulation results. This algorithm shows that the new technique provides more accurate results with fast convergence and small size effects over a wide range of plasma states.

Keywords: molecular dynamics simulation, thermal conductivity, nonideal complex plasma, Poiseuille flow

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248 A Randomized, Controlled Trial to Test Habit Formation Theory for Low Intensity Physical Exercise Promotion in Older Adults

Authors: Patrick Louie Robles, Jerry Suls, Ciaran Friel, Mark Butler, Samantha Gordon, Frank Vicari, Joan Duer-Hefele, Karina W. Davidson

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Physical activity guidelines focus on increasing moderate-intensity activity for older adults, but adherence to recommendations remains low. This is despite the fact that scientific evidence finds increasing physical activity is positively associated with health benefits. Behavior change techniques (BCTs) have demonstrated some effectiveness in reducing sedentary behavior and promoting physical activity. This pilot study uses a personalized trials (N-of-1) design, delivered virtually, to evaluate the efficacy of using five BCTs in increasing low-intensity physical activity (by 2,000 steps of walking per day) in adults aged 45-75 years old. The 5 BCTs described in habit formation theory are goal setting, action planning, rehearsal, rehearsal in a consistent context, and self-monitoring. The study recruited health system employees in the target age range who had no mobility restrictions and expressed interest in increasing their daily activity by a minimum of 2,000 steps per day at least five days per week. Participants were sent a Fitbit Charge 4 fitness tracker with an established study account and password. Participants were recommended to wear the Fitbit device 24/7 but were required to wear it for a minimum of ten hours per day. Baseline physical activity was measured by Fitbit for two weeks. Participants then engaged remotely with a clinical research coordinator to establish a “walking plan” that included a time and day interval (e.g., between 7am -8am on Monday-Friday), a location for the walk (e.g., park), and how much time the plan would need to achieve a minimum of 2,000 steps over their baseline average step count (20 minutes). All elements of the walking plan were required to remain consistent throughout the study. In the 10-week intervention phase of the study, participants received all five BCTs in a single, time-sensitive text message. The text message was delivered 30 minutes prior to the established walk time and signaled participants to begin walking when the context (i.e., day of the week, time of day) they pre-selected is encountered. Participants were asked to log both the start and conclusion of their activity session by pressing a button on the Fitbit tracker. Within 30 minutes of the planned conclusion of the activity session, participants received a text message with a link to a secure survey. Here, they noted whether they engaged in the BCTs when prompted and completed an automaticity survey to identify how “automatic” their walking behavior had become. At the end of their trial, participants received a personalized summary of their step data over time, helping them learn more about their responses to the five BCTs. Whether the use of these 5 ‘habit formation’ BCTs in combination elicits a change in physical activity behavior among older adults will be reported. This study will inform the feasibility of a virtually-delivered N-of-1 study design to effectively promote physical activity as a component of healthy aging.

Keywords: aging, exercise, habit, walking

Procedia PDF Downloads 113
247 Toward the Decarbonisation of EU Transport Sector: Impacts and Challenges of the Diffusion of Electric Vehicles

Authors: Francesca Fermi, Paola Astegiano, Angelo Martino, Stephanie Heitel, Michael Krail

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In order to achieve the targeted emission reductions for the decarbonisation of the European economy by 2050, fundamental contributions are required from both energy and transport sectors. The objective of this paper is to analyse the impacts of a largescale diffusion of e-vehicles, either battery-based or fuel cells, together with the implementation of transport policies aiming at decreasing the use of motorised private modes in order to achieve greenhouse gas emission reduction goals, in the context of a future high share of renewable energy. The analysis of the impacts and challenges of future scenarios on transport sector is performed with the ASTRA (ASsessment of TRAnsport Strategies) model. ASTRA is a strategic system-dynamic model at European scale (EU28 countries, Switzerland and Norway), consisting of different sub-modules related to specific aspects: the transport system (e.g. passenger trips, tonnes moved), the vehicle fleet (composition and evolution of technologies), the demographic system, the economic system, the environmental system (energy consumption, emissions). A key feature of ASTRA is that the modules are linked together: changes in one system are transmitted to other systems and can feed-back to the original source of variation. Thanks to its multidimensional structure, ASTRA is capable to simulate a wide range of impacts stemming from the application of transport policy measures: the model addresses direct impacts as well as second-level and third-level impacts. The simulation of the different scenarios is performed within the REFLEX project, where the ASTRA model is employed in combination with several energy models in a comprehensive Modelling System. From the transport sector perspective, some of the impacts are driven by the trend of electricity price estimated from the energy modelling system. Nevertheless, the major drivers to a low carbon transport sector are policies related to increased fuel efficiency of conventional drivetrain technologies, improvement of demand management (e.g. increase of public transport and car sharing services/usage) and diffusion of environmentally friendly vehicles (e.g. electric vehicles). The final modelling results of the REFLEX project will be available from October 2018. The analysis of the impacts and challenges of future scenarios is performed in terms of transport, environmental and social indicators. The diffusion of e-vehicles produces a consistent reduction of future greenhouse gas emissions, although the decarbonisation target can be achieved only with the contribution of complementary transport policies on demand management and supporting the deployment of low-emission alternative energy for non-road transport modes. The paper explores the implications through time of transport policy measures on mobility and environment, underlying to what extent they can contribute to a decarbonisation of the transport sector. Acknowledgements: The results refer to the REFLEX project which has received grants from the European Union’s Horizon 2020 research and innovation program under Grant Agreement No. 691685.

Keywords: decarbonisation, greenhouse gas emissions, e-mobility, transport policies, energy

Procedia PDF Downloads 129
246 An Online Space for Practitioners in the Water, Sanitation and Hygiene Sector

Authors: Olivier Mills, Bernard McDonell, Laura A. S. MacDonald

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The increasing availability and quality of internet access throughout the developing world provides an opportunity to utilize online spaces to disseminate water, sanitation and hygiene (WASH) knowledge to practitioners. Since 2001, CAWST has provided in-person education, training and consulting services to thousands of WASH practitioners all over the world, supporting them to start, troubleshoot, improve and expand their WASH projects. As CAWST continues to grow, the organization faces challenges in meeting demand from clients and in providing consistent, timely technical support. In 2012, CAWST began utilizing online spaces to expand its reach by developing a series of resources websites and webinars. CAWST has developed a WASH Education and Training resources website, a Biosand Filter (BSF) Knowledge Base, a Household Water Treatment and Safe Storage Knowledge Base, a mobile app for offline users, a live chat support tool, a WASH e-library, and a series of webinar-style online training sessions to complement its in-person capacity development services. In order to determine the preliminary outcomes of providing these online services, CAWST has monitored and analyzed registration to the online spaces, downloads of the educational materials, and webinar attendance; as well as conducted user surveys. The purpose of this analysis was to find out who was using the online spaces, where users came from, and how the resources were being used. CAWST’s WASH Resources website has served over 5,800 registered users from 3,000 organizations in 183 countries. Additionally, the BSF Knowledge Base has served over 1000 registered users from 68 countries, and over 540 people from 73 countries have attended CAWST’s online training sessions. This indicates that the online spaces are effectively reaching a large numbers of users, from a range of countries. A 2016 survey of the Biosand Filter Knowledge Base showed that approximately 61% of users are practitioners, and 39% are either researchers or students. Of the respondents, 46% reported using the BSF Knowledge Base to initiate a BSF project and 43% reported using the information to train BSF technicians. Finally, 61% indicated they would like even greater support from CAWST’s Technical Advisors going forward. The analysis has provided an encouraging indication that CAWST’s online spaces are contributing to its objective of engaging and supporting WASH practitioners to start, improve and expand their initiatives. CAWST has learned several lessons during the development of these online spaces, in particular related to the resources needed to create and maintain the spaces, and respond to the demand created. CAWST plans to continue expanding its online spaces, improving user experience of the sites, and involving new contributors and content types. Through the use of online spaces, CAWST has been able to increase its global reach and impact without significantly increasing its human resources by connecting WASH practitioners with the information they most need, in a practical and accessible manner. This paper presents on CAWST’s use of online spaces through the CAWST-developed platforms discussed above and the analysis of the use of these platforms.

Keywords: education and training, knowledge sharing, online resources, water and sanitation

Procedia PDF Downloads 244
245 Effect of Renin Angiotensin Pathway Inhibition on the Efficacy of Anti-programmed Cell Death (PD-1/L-1) Inhibitors in Advanced Non-small Cell Lung Cancer Patients- Comparison of Single Hospital Retrospective Assessment to the Published Literature

Authors: Esther Friedlander, Philip Friedlander

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The use of immunotherapy that inhibits programmed death-1 (PD-1) or its ligand PD-L1 confers survival benefits in patients with non-small cell lung cancer (NSCLC). However, approximately 45% of patients experience primary treatment resistance, necessitating the development of strategies to improve efficacy. While the renin-angiotensin system (RAS) has systemic hemodynamic effects, tissue-specific regulation exists along with modulation of immune activity in part through regulation of myeloid cell activity, leading to the hypothesis that RAS inhibition may improve anti-PD-1/L-1 efficacy. A retrospective analysis was conducted that included 173 advanced solid tumor cancer patients treated at Valley Hospital, a community Hospital in New Jersey, USA, who were treated with a PD-1/L-1 inhibitor in a defined time period showing a statistically significant relationship between RAS pathway inhibition (RASi through concomitant treatment with an ACE inhibitor or angiotensin receptor blocker) and positive efficacy to the immunotherapy that was independent of age, gender and cancer type. Subset analysis revealed strong numerical benefit for efficacy in both patients with squamous and nonsquamous NSCLC as determined by documented clinician assessment of efficacy and by duration of therapy. A PUBMED literature search was now conducted to identify studies assessing the effect of RAS pathway inhibition on anti-PD-1/L1 efficacy in advanced solid tumor patients and compare these findings to those seen in the Valley Hospital retrospective study with a focus on NSCLC specifically. A total of 11 articles were identified assessing the effects of RAS pathway inhibition on the efficacy of checkpoint inhibitor immunotherapy in advanced cancer patients. Of the 11 studies, 10 assessed the effect on survival of RASi in the context of treatment with anti-PD-1/PD-L1, while one assessed the effect on CTLA-4 inhibition. Eight of the studies included patients with NSCLC, while the remaining 2 were specific to genitourinary malignancies. Of the 8 studies, two were specific to NSCLC patients, with the remaining 6 studies including a range of cancer types, of which NSCLC was one. Of these 6 studies, only 2 reported specific survival data for the NSCLC subpopulation. Patient characteristics, multivariate analysis data and efficacy data seen in the 2 NSLCLC specific studies and in the 2 basket studies, which provided data on the NSCLC subpopulation, were compared to that seen in the Valley Hospital retrospective study supporting a broader effect of RASi on anti-PD-1/L1 efficacy in advanced NSLCLC with the majority of studies showing statistically significant benefit or strong statistical trends but with one study demonstrating worsened outcomes. This comparison of studies extends published findings to the community hospital setting and supports prospective assessment through randomized clinical trials of efficacy in NSCLC patients with pharmacodynamic components to determine the effect on immune cell activity in tumors and on the composition of the tumor microenvironment.

Keywords: immunotherapy, cancer, angiotensin, efficacy, PD-1, lung cancer, NSCLC

Procedia PDF Downloads 43
244 Financing the Welfare State in the United States: The Recent American Economic and Ideological Challenges

Authors: Rafat Fazeli, Reza Fazeli

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This paper focuses on the study of the welfare state and social wage in the leading liberal economy of the United States. The welfare state acquired a broad acceptance as a major socioeconomic achievement of the liberal democracy in the Western industrialized countries during the postwar boom period. The modern and modified vision of capitalist democracy offered, on the one hand, the possibility of high growth rate and, on the other hand, the possibility of continued progression of a comprehensive system of social support for a wider population. The economic crises of the 1970s, provided the ground for a great shift in economic policy and ideology in several Western countries, most notably the United States and the United Kingdom (and to a lesser extent Canada under Prime Minister Brian Mulroney). In the 1980s, the free market oriented reforms undertaken under Reagan and Thatcher greatly affected the economic outlook not only of the United States and the United Kingdom, but of the whole Western world. The movement which was behind this shift in policy is often called neo-conservatism. The neoconservatives blamed the transfer programs for the decline in economic performance during the 1970s and argued that cuts in spending were required to go back to the golden age of full employment. The agenda for both Reagan and Thatcher administrations was rolling back the welfare state, and their budgets included a wide range of cuts for social programs. The question is how successful were Reagan and Thatcher’s efforts to achieve retrenchment? The paper involves an empirical study concerning the distributive role of the welfare state in the two countries. Other studies have often concentrated on the redistributive effect of fiscal policy on different income brackets. This study examines the net benefit/ burden position of the working population with respect to state expenditures and taxes in the postwar period. This measurement will enable us to find out whether the working population has received a net gain (or net social wage). This study will discuss how the expansion of social expenditures and the trend of the ‘net social wage’ can be linked to distinct forms of economic and social organizations. This study provides an empirical foundation for analyzing the growing significance of ‘social wage’ or the collectivization of consumption and the share of social or collective consumption in total consumption of the working population in the recent decades. The paper addresses three other major questions. The first question is whether the expansion of social expenditures has posed any drag on capital accumulation and economic growth. The findings of this study provide an analytical foundation to evaluate the neoconservative claim that the welfare state is itself the source of economic stagnation that leads to the crisis of the welfare state. The second question is whether the increasing ideological challenges from the right and the competitive pressures of globalization have led to retrenchment of the American welfare states in the recent decades. The third question is how social policies have performed in the presence of the rising inequalities in the recent decades.

Keywords: the welfare state, social wage, The United States, limits to growth

Procedia PDF Downloads 187
243 Ethnobotanical and Laboratory Investigations of Plants Used for the Treatment of Typhoid Fever in Gombe State, North-Eastern Nigeria

Authors: Abubakar Bello Usman, Alhassan Muhammad Gani, Kolo Ibrahim

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The use of botanical raw materials to produce pharmaceuticals, herbal remedies, teas, spirits, cosmetics, sweets, dietary supplements, special industrial compounds and crude materials constitute an important global resource in terms of healthcare and economy. In Nigeria and other developing countries, the indigenous knowledge on the uses of plants lies with the older generation and the traditional healers. However, these custodians are decreasing in number due to death and other unforeseen occurrences. An Ethno-botanical survey was carried out to obtain information on the ethno medical values of wide range of plants used by the people of Gombe State, North-Eastern Nigeria, in the practice of healing and cure of typhoid (enteric) fever. Oral interviews were conducted so as to consider those with low literacy level who are involved in the practice of traditional medicine and thirty four (34) informants availed themselves for the interview and were consulted. All relevant information obtained from the respondents was recorded. A recent and valid nomenclature, along with local names, family names, part of the plant(s) used, methods of preparation and administration and fifty four (54) plant species belonging to 27 families as well as 7 unidentified species that are commonly used by the people of the state in ethnomedical treatment of the ailment were tabulated. Those interviewed included traditional practitioners, local herb sellers, traditional rulers, hunters, farmers and patients. Specific questions were asked and information supplied by informants was promptly documented. Results showed that the people of Gombe State are knowledgeable on herbal medicine in the treatment of diseases and ailments. Furthermore, the aqueous leaf extracts of Senna siamea, the plant species with the highest PPK (percentage of people who have knowledge about the use of a species for treating typhoid fever) in this ethnobotanical survey, was tested for its activity against clinical isolates of Salmonella typhi using the agar well diffusion method. The aqueous extracts showed some activity (zones of inhibition 11, 9, 7.5, 3.5, 1.3 mm) at 2000, 1800, 1600, 1400, 1200 µg/ml concentrations respectively. Preliminary phytochemical studies of the aqueous leaf extracts of the plant revealed the presence of secondary metabolites such as alkaloids, saponins, tannins, flavonoids and cardiac glycosides. Though a large number of traditionally used plants for the treatment of enteric fever were identified, further scientific validation of the traditional claims of anti-typhoid properties is imperative. This would establish their candidature for any possible future research for active principles and the possible development of new cheaper and more effective anti-typhoid drugs, as well as in the conservation of this rich diversity of medicinal plants.

Keywords: antimicrobial activities, ethnobotany, gombe state, north-eastern Nigeria, phytochemical screening, senna siamea, typhoid fever

Procedia PDF Downloads 307
242 Becoming Vegan: The Theory of Planned Behavior and the Moderating Effect of Gender

Authors: Estela Díaz

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This article aims to make three contributions. First, build on the literature on ethical decision-making literature by exploring factors that influence the intention of adopting veganism. Second, study the superiority of extended models of the Theory of Planned Behavior (TPB) for understanding the process involved in forming the intention of adopting veganism. Third, analyze the moderating effect of gender on TPB given that attitudes and behavior towards animals are gender-sensitive. No study, to our knowledge, has examined these questions. Veganism is not a diet but a political and moral stand that exclude, for moral reasons, the use of animals. Although there is a growing interest in studying veganism, it continues being overlooked in empirical research, especially within the domain of social psychology. TPB has been widely used to study a broad range of human behaviors, including moral issues. Nonetheless, TPB has rarely been applied to examine ethical decisions about animals and, even less, to veganism. Hence, the validity of TPB in predicting the intention of adopting veganism remains unanswered. A total of 476 non-vegan Spanish university students (55.6% female; the mean age was 23.26 years, SD= 6.1) responded to online and pencil-and-paper self-reported questionnaire based on previous studies. TPB extended models incorporated two background factors: ‘general attitudes towards humanlike-attributes ascribed to animals’ (AHA) (capacity for reason/emotions/suffer, moral consideration, and affect-towards-animals); and ‘general attitudes towards 11 uses of animals’ (AUA). SPSS 22 and SmartPLS 3.0 were used for statistical analyses. This study constructed a second-order reflective-formative model and took the multi-group analysis (MGA) approach to study gender effects. Six models of TPB (the standard and five competing) were tested. No a priori hypotheses were formulated. The results gave partial support to TPB. Attitudes (ATTV) (β = .207, p < .001), subjective norms (SNV) (β = .323, p < .001), and perceived control behavior (PCB) (β = .149, p < .001) had a significant direct effect on intentions (INTV). This model accounted for 27,9% of the variance in intention (R2Adj = .275) and had a small predictive relevance (Q2 = .261). However, findings from this study reveal that contrary to what TPB generally proposes, the effect of the background factors on intentions was not fully mediated by the proximal constructs of intentions. For instance, in the final model (Model#6), both factors had significant multiple indirect effect on INTV (β = .074, 95% C = .030, .126 [AHA:INTV]; β = .101, 95% C = .055, .155 [AUA:INTV]) and significant direct effect on INTV (β = .175, p < .001 [AHA:INTV]; β = .100, p = .003 [AUA:INTV]). Furthermore, the addition of direct paths from background factors to intentions improved the explained variance in intention (R2 = .324; R2Adj = .317) and the predictive relevance (Q2 = .300) over the base-model. This supports existing literature on the superiority of enhanced TPB models to predict ethical issues; which suggests that moral behavior may add additional complexity to decision-making. Regarding gender effect, MGA showed that gender only moderated the influence of AHA on ATTV (e.g., βWomen−βMen = .296, p < .001 [Model #6]). However, other observed gender differences (e.g. the explained variance of the model for intentions were always higher for men that for women, for instance, R2Women = .298; R2Men = .394 [Model #6]) deserve further considerations, especially for developing more effective communication strategies.

Keywords: veganism, Theory of Planned Behavior, background factors, gender moderation

Procedia PDF Downloads 318
241 Evaluation of Alternative Approaches for Additional Damping in Dynamic Calculations of Railway Bridges under High-Speed Traffic

Authors: Lara Bettinelli, Bernhard Glatz, Josef Fink

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Planning engineers and researchers use various calculation models with different levels of complexity, calculation efficiency and accuracy in dynamic calculations of railway bridges under high-speed traffic. When choosing a vehicle model to depict the dynamic loading on the bridge structure caused by passing high-speed trains, different goals are pursued: On the one hand, the selected vehicle models should allow the calculation of a bridge’s vibrations as realistic as possible. On the other hand, the computational efficiency and manageability of the models should be preferably high to enable a wide range of applications. The commonly adopted and straightforward vehicle model is the moving load model (MLM), which simplifies the train to a sequence of static axle loads moving at a constant speed over the structure. However, the MLM can significantly overestimate the structure vibrations, especially when resonance events occur. More complex vehicle models, which depict the train as a system of oscillating and coupled masses, can reproduce the interaction dynamics between the vehicle and the bridge superstructure to some extent and enable the calculation of more realistic bridge accelerations. At the same time, such multi-body models require significantly greater processing capacities and precise knowledge of various vehicle properties. The European standards allow for applying the so-called additional damping method when simple load models, such as the MLM, are used in dynamic calculations. An additional damping factor depending on the bridge span, which should take into account the vibration-reducing benefits of the vehicle-bridge interaction, is assigned to the supporting structure in the calculations. However, numerous studies show that when the current standard specifications are applied, the calculation results for the bridge accelerations are in many cases still too high compared to the measured bridge accelerations, while in other cases, they are not on the safe side. A proposal to calculate the additional damping based on extensive dynamic calculations for a parametric field of simply supported bridges with a ballasted track was developed to address this issue. In this contribution, several different approaches to determine the additional damping of the supporting structure considering the vehicle-bridge interaction when using the MLM are compared with one another. Besides the standard specifications, this includes the approach mentioned above and two additional recently published alternative formulations derived from analytical approaches. For a bridge catalogue of 65 existing bridges in Austria in steel, concrete or composite construction, calculations are carried out with the MLM for two different high-speed trains and the different approaches for additional damping. The results are compared with the calculation results obtained by applying a more sophisticated multi-body model of the trains used. The evaluation and comparison of the results allow assessing the benefits of different calculation concepts for the additional damping regarding their accuracy and possible applications. The evaluation shows that by applying one of the recently published redesigned additional damping methods, the calculation results can reflect the influence of the vehicle-bridge interaction on the design-relevant structural accelerations considerably more reliable than by using normative specifications.

Keywords: Additional Damping Method, Bridge Dynamics, High-Speed Railway Traffic, Vehicle-Bridge-Interaction

Procedia PDF Downloads 143
240 Comparative Study of Outcome of Patients with Wilms Tumor Treated with Upfront Chemotherapy and Upfront Surgery in Alexandria University Hospitals

Authors: Golson Mohamed, Yasmine Gamasy, Khaled EL-Khatib, Anas Al-Natour, Shady Fadel, Haytham Rashwan, Haytham Badawy, Nadia Farghaly

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Introduction: Wilm's tumor is the most common malignant renal tumor in children. Much progress has been made in the management of patients with this malignancy over the last 3 decades. Today treatments are based on several trials and studies conducted by the International Society of Pediatric Oncology (SIOP) in Europe and National Wilm's Tumor Study Group (NWTS) in the USA. It is necessary for us to understand why do we follow either of the protocols, NWTS which follows the upfront surgery principle or the SIOP which follows the upfront chemotherapy principle in all stages of the disease. Objective: The aim of is to assess outcome in patients treated with preoperative chemotherapy and patients treated with upfront surgery to compare their effect on overall survival. Study design: to decide which protocol to follow, study was carried out on records for patients aged 1 day to 18 years old suffering from Wilm's tumor who were admitted to Alexandria University Hospital, pediatric oncology, pediatric urology and pediatric surgery departments, with a retrospective survey records from 2010 to 2015, Design and editing of the transfer sheet with a (PRISMA flow study) Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Data were fed to the computer and analyzed using IBM SPSS software package version 20.0. (11) Qualitative data were described using number and percent. Quantitative data were described using Range (minimum and maximum), mean, standard deviation and median. Comparison between different groups regarding categorical variables was tested using Chi-square test. When more than 20% of the cells have expected count less than 5, correction for chi-square was conducted using Fisher’s Exact test or Monte Carlo correction. The distributions of quantitative variables were tested for normality using Kolmogorov-Smirnov test, Shapiro-Wilk test, and D'Agstino test, if it reveals normal data distribution, parametric tests were applied. If the data were abnormally distributed, non-parametric tests were used. For normally distributed data, a comparison between two independent populations was done using independent t-test. For abnormally distributed data, comparison between two independent populations was done using Mann-Whitney test. Significance of the obtained results was judged at the 5% level. Results: A significantly statistical difference was observed for survival between the two studied groups favoring the upfront chemotherapy(86.4%)as compared to the upfront surgery group (59.3%) where P=0.009. As regard complication, 20 cases (74.1%) out of 27 were complicated in the group of patients treated with upfront surgery. Meanwhile, 30 cases (68.2%) out of 44 had complications in patients treated with upfront chemotherapy. Also, the incidence of intraoperative complication (rupture) was less in upfront chemotherapy group as compared to upfront surgery group. Conclusion: Upfront chemotherapy has superiority over upfront surgery.As the patient who started with upfront chemotherapy shown, higher survival rate, less percent in complication, less percent needed for radiotherapy, and less rate in recurrence.

Keywords: Wilm's tumor, renal tumor, chemotherapy, surgery

Procedia PDF Downloads 296
239 Soybean Lecithin Based Reverse Micellar Extraction of Pectinase from Synthetic Solution

Authors: Sivananth Murugesan, I. Regupathi, B. Vishwas Prabhu, Ankit Devatwal, Vishnu Sivan Pillai

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Pectinase is an important enzyme which has a wide range of applications including textile processing and bioscouring of cotton fibers, coffee and tea fermentation, purification of plant viruses, oil extraction etc. Selective separation and purification of pectinase from fermentation broth and recover the enzyme form process stream for reuse are cost consuming process in most of the enzyme based industries. It is difficult to identify a suitable medium to enhance enzyme activity and retain its enzyme characteristics during such processes. The cost effective, selective separation of enzymes through the modified Liquid-liquid extraction is of current research interest worldwide. Reverse micellar extraction, globally acclaimed Liquid-liquid extraction technique is well known for its separation and purification of solutes from the feed which offers higher solute specificity and partitioning, ease of operation and recycling of extractants used. Surfactant concentrations above critical micelle concentration to an apolar solvent form micelles and addition of micellar phase to water in turn forms reverse micelles or water-in-oil emulsions. Since, electrostatic interaction plays a major role in the separation/purification of solutes using reverse micelles. These interaction parameters can be altered with the change in pH, addition of cosolvent, surfactant and electrolyte and non-electrolyte. Even though many chemical based commercial surfactant had been utilized for this purpose, the biosurfactants are more suitable for the purification of enzymes which are used in food application. The present work focused on the partitioning of pectinase from the synthetic aqueous solution within the reverse micelle phase formed by a biosurfactant, Soybean Lecithin dissolved in chloroform. The critical micelle concentration of soybean lecithin/chloroform solution was identified through refractive index and density measurements. Effect of surfactant concentrations above and below the critical micelle concentration was considered to study its effect on enzyme activity, enzyme partitioning within the reverse micelle phase. The effect of pH and electrolyte salts on the partitioning behavior was studied by varying the system pH and concentration of different salts during forward and back extraction steps. It was observed that lower concentrations of soybean lecithin enhanced the enzyme activity within the water core of the reverse micelle with maximizing extraction efficiency. The maximum yield of pectinase of 85% with a partitioning coefficient of 5.7 was achieved at 4.8 pH during forward extraction and 88% yield with a partitioning coefficient of 7.1 was observed during backward extraction at a pH value of 5.0. However, addition of salt decreased the enzyme activity and especially at higher salt concentrations enzyme activity declined drastically during both forward and back extraction steps. The results proved that reverse micelles formed by Soybean Lecithin and chloroform may be used for the extraction of pectinase from aqueous solution. Further, the reverse micelles can be considered as nanoreactors to enhance enzyme activity and maximum utilization of substrate at optimized conditions, which are paving a way to process intensification and scale-down.

Keywords: pectinase, reverse micelles, soybean lecithin, selective partitioning

Procedia PDF Downloads 345
238 Catalytic Dehydrogenation of Formic Acid into H2/CO2 Gas: A Novel Approach

Authors: Ayman Hijazi, Witold Kwapinski, J. J. Leahy

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Finding a sustainable alternative energy to fossil fuel is an urgent need as various environmental challenges in the world arise. Therefore, formic acid (FA) decomposition has been an attractive field that lies at the center of biomass platform, comprising a potential pool of hydrogen energy that stands as a new energy vector. Liquid FA features considerable volumetric energy density of 6.4 MJ/L and a specific energy density of 5.3 MJ/Kg that qualifies it in the prime seat as an energy source for transportation infrastructure. Additionally, the increasing research interest in FA decomposition is driven by the need of in-situ H2 production, which plays a key role in the hydrogenation reactions of biomass into higher value components. It is reported elsewhere in literature that catalytic decomposition of FA is usually performed in poorly designed setup using simple glassware under magnetic stirring, thus demanding further energy investment to retain the used catalyst. it work suggests an approach that integrates designing a novel catalyst featuring magnetic property with a robust setup that minimizes experimental & measurement discrepancies. One of the most prominent active species for dehydrogenation/hydrogenation of biomass compounds is palladium. Accordingly, we investigate the potential of engrafting palladium metal onto functionalized magnetic nanoparticles as a heterogeneous catalyst to favor the production of CO-free H2 gas from FA. Using ordinary magnet to collect the spent catalyst renders core-shell magnetic nanoparticles as the backbone of the process. Catalytic experiments were performed in a jacketed batch reactor equipped with an overhead stirrer under inert medium. Through a novel approach, FA is charged into the reactor via high-pressure positive displacement pump at steady state conditions. The produced gas (H2+CO2) was measured by connecting the gas outlet to a measuring system based on the amount of the displaced water. The novelty of this work lies in designing a very responsive catalyst, pumping consistent amount of FA into a sealed reactor running at steady state mild temperatures, and continuous gas measurement, along with collecting the used catalyst without the need for centrifugation. Catalyst characterization using TEM, XRD, SEM, and CHN elemental analyzer provided us with details of catalyst preparation and facilitated new venues to alter the nanostructure of the catalyst framework. Consequently, the introduction of amine groups has led to appreciable improvements in terms of dispersion of the doped metals and eventually attaining nearly complete conversion (100%) of FA after 7 hours. The relative importance of the process parameters such as temperature (35-85°C), stirring speed (150-450rpm), catalyst loading (50-200mgr.), and Pd doping ratio (0.75-1.80wt.%) on gas yield was assessed by a Taguchi design-of-experiment based model. Experimental results showed that operating at lower temperature range (35-50°C) yielded more gas while the catalyst loading and Pd doping wt.% were found to be the most significant factors with a P-values 0.026 & 0.031, respectively.

Keywords: formic acid decomposition, green catalysis, hydrogen, mesoporous silica, process optimization, nanoparticles

Procedia PDF Downloads 21
237 Detection of Triclosan in Water Based on Nanostructured Thin Films

Authors: G. Magalhães-Mota, C. Magro, S. Sério, E. Mateus, P. A. Ribeiro, A. B. Ribeiro, M. Raposo

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Triclosan [5-chloro-2-(2,4-dichlorophenoxy) phenol], belonging to the class of Pharmaceuticals and Personal Care Products (PPCPs), is a broad-spectrum antimicrobial agent and bactericide. Because of its antimicrobial efficacy, it is widely used in personal health and skin care products, such as soaps, detergents, hand cleansers, cosmetics, toothpastes, etc. However, it has been considered to disrupt the endocrine system, for instance, thyroid hormone homeostasis and possibly the reproductive system. Considering the widespread use of triclosan, it is expected that environmental and food safety problems regarding triclosan will increase dramatically. Triclosan has been found in river water samples in both North America and Europe and is likely widely distributed wherever triclosan-containing products are used. Although significant amounts are removed in sewage plants, considerable quantities remain in the sewage effluent, initiating widespread environmental contamination. Triclosan undergoes bioconversion to methyl-triclosan, which has been demonstrated to bio accumulate in fish. In addition, triclosan has been found in human urine samples from persons with no known industrial exposure and in significant amounts in samples of mother's milk, demonstrating its presence in humans. The action of sunlight in river water is known to turn triclosan into dioxin derivatives and raises the possibility of pharmacological dangers not envisioned when the compound was originally utilized. The aim of this work is to detect low concentrations of triclosan in an aqueous complex matrix through the use of a sensor array system, following the electronic tongue concept based on impedance spectroscopy. To achieve this goal, we selected the appropriate molecules to the sensor so that there is a high affinity for triclosan and whose sensitivity ensures the detection of concentrations of at least nano-molar. Thin films of organic molecules and oxides have been produced by the layer-by-layer (LbL) technique and sputtered onto glass solid supports already covered by gold interdigitated electrodes. By submerging the films in complex aqueous solutions with different concentrations of triclosan, resistance and capacitance values were obtained at different frequencies. The preliminary results showed that an array of interdigitated electrodes sensor coated or uncoated with different LbL and films, can be used to detect TCS traces in aqueous solutions in a wide range concentration, from 10⁻¹² to 10⁻⁶ M. The PCA method was applied to the measured data, in order to differentiate the solutions with different concentrations of TCS. Moreover, was also possible to trace a curve, the plot of the logarithm of resistance versus the logarithm of concentration, which allowed us to fit the plotted data points with a decreasing straight line with a slope of 0.022 ± 0.006 which corresponds to the best sensitivity of our sensor. To find the sensor resolution near of the smallest concentration (Cs) used, 1pM, the minimum measured value which can be measured with resolution is 0.006, so the ∆logC =0.006/0.022=0.273, and, therefore, C-Cs~0.9 pM. This leads to a sensor resolution of 0.9 pM for the smallest concentration used, 1pM. This attained detection limit is lower than the values obtained in the literature.

Keywords: triclosan, layer-by-layer, impedance spectroscopy, electronic tongue

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236 Harnessing Nature's Fury: Hyptis Suaveolens Loaded Bioactive Liposome for Photothermal Therapy of Lung Cancer

Authors: Sajmina Khatun, Monika Pebam, Aravind Kumar Rengan

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Photothermal therapy, a subset of nanomedicine, takes advantage of light-absorbing agents to generate localized heat, selectively eradicating cancer cells. This innovative approach minimizes damage to healthy tissues and offers a promising avenue for targeted cancer treatment. Unlike conventional therapies, photothermal therapy harnesses the power of light to combat malignancies precisely and effectively, showcasing its potential to revolutionize cancer treatment paradigms. The combined strengths of nanomedicine and photothermal therapy signify a transformative shift toward more effective, targeted, and tolerable cancer treatments in the medical landscape. Utilizing natural products becomes instrumental in formulating diverse bioactive medications owing to their various pharmacological properties attributed to the existence of phenolic structures, triterpenoids, and similar compounds. Hyptis suaveolens, commonly known as pignut, stands as an aromatic herb within the Lamiaceae family and represents a valuable therapeutic plant. Flourishing in swamps and alongside tropical and subtropical roadsides, these noxious weeds impede the development of adjacent plants. Hyptis suaveolens ranks among the most globally distributed alien invasive species. The present investigation revealed that a versatile, biodegradable liposome nanosystem (HIL NPs), incorporating bioactive molecules from Hyptis suaveolens, exhibits effective bioavailability to cancer cells, enabling tumor ablation upon near-infrared (NIR) laser exposure. The components within the nanosystem, specifically the bioactive molecules from Hyptis, function as anticancer agents, aiding in the photothermal ablation of highly metastatic lung cancer cells. Despite being a prolific weed impeding neighboring plant growth, Hyptis suaveolens showcases therapeutic benefits through its bioactive compounds. The obtained HIL NPs, characterized as a photothermally active liposome nanosystem, demonstrate a pronounced fluorescence absorption peak in the NIR range and achieve a high photothermal conversion efficiency under NIR laser irradiation. Transmission electron microscopy (TEM) and particle size analysis reveal that HIL NPs possess a spherical shape with a size of 141 ± 30 nm. Moreover, in vitro assessments of HIL NPs against lung cancer cell lines (A549) indicate effective anticancer activity through a combined cytotoxic effect and hyperthermia. Tumor ablation is facilitated by apoptosis induced by the overexpression of ɣ-H2AX, arresting cancer cell proliferation. Consequently, the multifunctional and biodegradable nanosystem (HIL NPs), incorporating bioactive compounds from Hyptis, provides valuable perspectives for developing an innovative therapeutic strategy originating from a challenging weed. This approach holds promise for potential applications in both bioimaging and the combined use of phyto-photothermal therapy for cancer treatment.

Keywords: bioactive liposome, hyptis suaveolens, photothermal therapy, lung cancer

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235 The Influence of Human Movement on the Formation of Adaptive Architecture

Authors: Rania Raouf Sedky

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Adaptive architecture relates to buildings specifically designed to adapt to their residents and their environments. To design a biologically adaptive system, we can observe how living creatures in nature constantly adapt to different external and internal stimuli to be a great inspiration. The issue is not just how to create a system that is capable of change but also how to find the quality of change and determine the incentive to adapt. The research examines the possibilities of transforming spaces using the human body as an active tool. The research also aims to design and build an effective dynamic structural system that can be applied on an architectural scale and integrate them all into the creation of a new adaptive system that allows us to conceive a new way to design, build and experience architecture in a dynamic manner. The main objective was to address the possibility of a reciprocal transformation between the user and the architectural element so that the architecture can adapt to the user, as the user adapts to architecture. The motivation is the desire to deal with the psychological benefits of an environment that can respond and thus empathize with human emotions through its ability to adapt to the user. Adaptive affiliations of kinematic structures have been discussed in architectural research for more than a decade, and these issues have proven their effectiveness in developing kinematic structures, responsive and adaptive, and their contribution to 'smart architecture'. A wide range of strategies have been used in building complex kinetic and robotic systems mechanisms to achieve convertibility and adaptability in engineering and architecture. One of the main contributions of this research is to explore how the physical environment can change its shape to accommodate different spatial displays based on the movement of the user’s body. The main focus is on the relationship between materials, shape, and interactive control systems. The intention is to develop a scenario where the user can move, and the structure interacts without any physical contact. The soft form of shifting language and interaction control technology will provide new possibilities for enriching human-environmental interactions. How can we imagine a space in which to construct and understand its users through physical gestures, visual expressions, and response accordingly? How can we imagine a space whose interaction depends not only on preprogrammed operations but on real-time feedback from its users? The research also raises some important questions for the future. What would be the appropriate structure to show physical interaction with the dynamic world? This study concludes with a strong belief in the future of responsive motor structures. We imagine that they are developing the current structure and that they will radically change the way spaces are tested. These structures have obvious advantages in terms of energy performance and the ability to adapt to the needs of users. The research highlights the interface between remote sensing and a responsive environment to explore the possibility of an interactive architecture that adapts to and responds to user movements. This study ends with a strong belief in the future of responsive motor structures. We envision that it will improve the current structure and that it will bring a fundamental change to the way in which spaces are tested.

Keywords: adaptive architecture, interactive architecture, responsive architecture, tensegrity

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234 Brittle Fracture Tests on Steel Bridge Bearings: Application of the Potential Drop Method

Authors: Natalie Hoyer

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Usually, steel structures are designed for the upper region of the steel toughness-temperature curve. To address the reduced toughness properties in the temperature transition range, additional safety assessments based on fracture mechanics are necessary. These assessments enable the appropriate selection of steel materials to prevent brittle fracture. In this context, recommendations were established in 2011 to regulate the appropriate selection of steel grades for bridge bearing components. However, these recommendations are no longer fully aligned with more recent insights: Designing bridge bearings and their components in accordance with DIN EN 1337 and the relevant sections of DIN EN 1993 has led to an increasing trend of using large plate thicknesses, especially for long-span bridges. However, these plate thicknesses surpass the application limits specified in the national appendix of DIN EN 1993-2. Furthermore, compliance with the regulations outlined in DIN EN 1993-1-10 regarding material toughness and through-thickness properties requires some further modifications. Therefore, these standards cannot be directly applied to the material selection for bearings without additional information. In addition, recent findings indicate that certain bridge bearing components are subjected to high fatigue loads, necessitating consideration in structural design, material selection, and calculations. To address this issue, the German Center for Rail Traffic Research initiated a research project aimed at developing a proposal to enhance the existing standards. This proposal seeks to establish guidelines for the selection of steel materials for bridge bearings to prevent brittle fracture, particularly for thick plates and components exposed to specific fatigue loads. The results derived from theoretical analyses, including finite element simulations and analytical calculations, are verified through component testing on a large-scale. During these large-scale tests, where a brittle failure is deliberately induced in a bearing component, an artificially generated defect is introduced into the specimen at the predetermined hotspot. Subsequently, a dynamic load is imposed until the crack initiation process transpires, replicating realistic conditions akin to a sharp notch resembling a fatigue crack. To stop the action of the dynamic load in time, it is important to precisely determine the point at which the crack size transitions from stable crack growth to unstable crack growth. To achieve this, the potential drop measurement method is employed. The proposed paper informs about the choice of measurement method (alternating current potential drop (ACPD) or direct current potential drop (DCPD)), presents results from correlations with created FE models, and may proposes a new approach to introduce beach marks into the fracture surface within the framework of potential drop measurement.

Keywords: beach marking, bridge bearing design, brittle fracture, design for fatigue, potential drop

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233 Synthesis of Smart Materials Based on Polyaniline Coated Fibers

Authors: Mihaela Beregoi, Horia Iovu, Cristina Busuioc, Alexandru Evanghelidis, Elena Matei, Monica Enculescu, Ionut Enculescu

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Nanomaterials field is very attractive for all researchers who are attempting to develop new devices with the same or improved properties than the micro-sized ones, while reducing the reagents and power consumptions. In this way, a wide range of nanomaterials were fabricated and integrated in applications for electronics, optoelectronics, solar cells, tissue reconstruction and drug delivery. Obviously, the most appealing ones are those dedicated to the medical domain. Different types of nano-sized materials, such as particles, fibers, films etc., can be synthesized by using physical, chemical or electrochemical methods. One of these techniques is electrospinning, which enable the production of fibers with nanometric dimensions by pumping a polymeric solution in a high electric field; due to the electrostatic charging and solvent evaporation, the precursor mixture is converted into nonwoven meshes with different fiber densities and mechanical properties. Moreover, polyaniline is a conducting polymer with interesting optical properties, suitable for displays and electrochromic windows. Otherwise, polyaniline is an electroactive polymer that can contract/expand by applying electric stimuli, due to the oxidation/reduction reactions which take place in the polymer chains. These two main properties can be exploited in order to synthesize smart materials that change their dimensions, exhibiting in the same time good electrochromic properties. In the context aforesaid, a poly(methyl metacrylate) solution was spun to get webs composed of fibers with diameter values between 500 nm and 1 µm. Further, the polymer meshes were covered with a gold layer in order to make them conductive and also appropriate as working electrode in an electrochemical cell. The gold shell was deposited by DC sputtering. Such metalized fibers can be transformed into smart materials by covering them with a thin layer of conductive polymer. Thus, the webs were coated with a polyaniline film by the electrochemical route, starting from and aqueous solution of aniline and sulfuric acid, where sulfuric acid acts as oxidant agent. For the polymerization of aniline, a saturated calomel electrode was employed as reference, a platinum plate as counter electrode and the gold covered webs as working electrode. Chronoamperometry was selected as deposition method for polyaniline, by modifying the deposition time. Metalized meshes with different fiber densities were used, the transmission ranging between 70 and 80 %. The morphological investigation showed that polyaniline layer has a granular structure for all deposition experiments. As well, some preliminary optical tests were done by using sulfuric acid as electrolyte, which revealed the modification of polyaniline colour from green to dark blue when applying a voltage. In conclusion, new multilayered materials were obtained by a simple approach: the merge of the electrospinning method benefits with polyaniline chemistry. This synthesis method allows the fabrication of structures with reproducible characteristics, suitable for display or tissue substituents.

Keywords: electrospinning, fibers, smart materials, polyaniline

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232 Deep Learning-Based Classification of 3D CT Scans with Real Clinical Data; Impact of Image format

Authors: Maryam Fallahpoor, Biswajeet Pradhan

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Background: Artificial intelligence (AI) serves as a valuable tool in mitigating the scarcity of human resources required for the evaluation and categorization of vast quantities of medical imaging data. When AI operates with optimal precision, it minimizes the demand for human interpretations and, thereby, reduces the burden on radiologists. Among various AI approaches, deep learning (DL) stands out as it obviates the need for feature extraction, a process that can impede classification, especially with intricate datasets. The advent of DL models has ushered in a new era in medical imaging, particularly in the context of COVID-19 detection. Traditional 2D imaging techniques exhibit limitations when applied to volumetric data, such as Computed Tomography (CT) scans. Medical images predominantly exist in one of two formats: neuroimaging informatics technology initiative (NIfTI) and digital imaging and communications in medicine (DICOM). Purpose: This study aims to employ DL for the classification of COVID-19-infected pulmonary patients and normal cases based on 3D CT scans while investigating the impact of image format. Material and Methods: The dataset used for model training and testing consisted of 1245 patients from IranMehr Hospital. All scans shared a matrix size of 512 × 512, although they exhibited varying slice numbers. Consequently, after loading the DICOM CT scans, image resampling and interpolation were performed to standardize the slice count. All images underwent cropping and resampling, resulting in uniform dimensions of 128 × 128 × 60. Resolution uniformity was achieved through resampling to 1 mm × 1 mm × 1 mm, and image intensities were confined to the range of (−1000, 400) Hounsfield units (HU). For classification purposes, positive pulmonary COVID-19 involvement was designated as 1, while normal images were assigned a value of 0. Subsequently, a U-net-based lung segmentation module was applied to obtain 3D segmented lung regions. The pre-processing stage included normalization, zero-centering, and shuffling. Four distinct 3D CNN models (ResNet152, ResNet50, DensNet169, and DensNet201) were employed in this study. Results: The findings revealed that the segmentation technique yielded superior results for DICOM images, which could be attributed to the potential loss of information during the conversion of original DICOM images to NIFTI format. Notably, ResNet152 and ResNet50 exhibited the highest accuracy at 90.0%, and the same models achieved the best F1 score at 87%. ResNet152 also secured the highest Area under the Curve (AUC) at 0.932. Regarding sensitivity and specificity, DensNet201 achieved the highest values at 93% and 96%, respectively. Conclusion: This study underscores the capacity of deep learning to classify COVID-19 pulmonary involvement using real 3D hospital data. The results underscore the significance of employing DICOM format 3D CT images alongside appropriate pre-processing techniques when training DL models for COVID-19 detection. This approach enhances the accuracy and reliability of diagnostic systems for COVID-19 detection.

Keywords: deep learning, COVID-19 detection, NIFTI format, DICOM format

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231 Cross-Sectional Associations between Deprivation Status and Physical Activity, Dietary Behaviours, Health-Related Variables, and Health-Related Quality of Life among Children Aged 9-11 Years

Authors: Maria Cardova

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Aim and objectives: The purpose of this studywas to explore to what extent the deprivation statusinfluenced children’s physical activity, dietary behaviour, and health outcomes such as weight status. Background: The United Kingdom’s childhood obesity rates are currently ranked among the highest in Europe. North West England deals with highest rates of childhood obesity. Data from the UK Millennium Cohort Study suggested a deprivation gradient to childhood obesity in England, with obesity rates being the highest in the most deprived areas. Traditionally, it has been individual conception of health, but the contemporary stance is that health behaviours affecting obesity are influenced by a broad range of factors operating at multiple levels. According to socio-ecological model of health behaviour, differences in obesity rates and health outcomes are likely explained by differences in lifestyle behaviours including physical activity and diet behaviours. However, higher rates of obesity among deprived children are not due to physical inactivity, in fact, most socially disadvantaged children are the most physically active. Poor diet including high consumption of fast food and sugar-sweetened beverages and low consumption of fruit and vegetables was found to be the most prevalent among adolescents living in poverty. Methods: This study adopted quantitative approach. It consisted of combination of basic demographic data, anthropometry, and questionnaires. Children (N = 165, mean age = 10.04 years; 53.33% female; 46.66% male) completed survey packs during school day including KIDSCREEN, Youth Activity Profile, Beverage and Snack Questionnaire, and Child Body Image Scale questionnaires as well as had anthropometric measurements taken including Body mass index, waist circumference, weight, and height. Children’s deprivation status was based on the English Indices of Multiple Deprivation scores of the school they attended. Results: Children from more deprived areas had higher weight status, waist circumference. Deprivation status had also effect on some dimensions of the KIDSCREEN questionnaire, such as that those from more deprived areas felt less socially accepted and bullied by their peers, had worse feelings about themselves such as body image, and more difficulty with school and learning. Children from more deprived areas reported higher rates of physical activity and also differences in snack and fruit and vegetable intake than their more affluent peers. Conclusion: Results demonstrated that, children living in the most-deprived areas appear to be at greater risk of unfavourable health-related variables and behaviours and are exposed to home and neighbourhood environments that are less conducive to health-promoting behaviours compared to their peers from less deprived areas. These findings indicate that children living in highly deprived areas represent an important group for future interventions designed to promote health-behaviours that would impact on the quality of life of the child and other health variables such as weight status.

Keywords: children, dietary behaviour, health, obesity, physical Activity, weight Status

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230 On-Farm Biopurification Systems: Fungal Bioaugmentation of Biomixtures For Carbofuran Removal

Authors: Carlos E. Rodríguez-Rodríguez, Karla Ruiz-Hidalgo, Kattia Madrigal-Zúñiga, Juan Salvador Chin-Pampillo, Mario Masís-Mora, Elizabeth Carazo-Rojas

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One of the main causes of contamination linked to agricultural activities is the spillage and disposal of pesticides, especially during the loading, mixing or cleaning of agricultural spraying equipment. One improvement in the handling of pesticides is the use of biopurification systems (BPS), simple and cheap degradation devices where the pesticides are biologically degraded at accelerated rates. The biologically active core of BPS is the biomixture, which is constituted by soil pre-exposed to the target pesticide, a lignocellulosic substrate to promote the activity of ligninolitic fungi and a humic component (peat or compost), mixed at a volumetric proportion of 50:25:25. Considering the known ability of lignocellulosic fungi to degrade a wide range of organic pollutants, and the high amount of lignocellulosic waste used in biomixture preparation, the bioaugmentation of biomixtures with these fungi represents an interesting approach for improving biomixtures. The present work aimed at evaluating the effect of the bioaugmentation of rice husk based biomixtures with the fungus Trametes versicolor in the removal of the insectice/nematicide carbofuran (CFN) and to optimize the composition of the biomixture to obtain the best performance in terms of CFN removal and mineralization, reduction in formation of transformation products and decrease in residual toxicity of the matrix. The evaluation of several lignocellulosic residues (rice husk, wood chips, coconut fiber, sugarcane bagasse or newspaper print) revealed the best colonization by T. versicolor in rice husk. Pre-colonized rice husk was then used in the bioaugmentation of biomixtures also containing soil pre-exposed to CFN and either peat (GTS biomixture) or compost (GCS biomixture). After spiking with 10 mg/kg CBF, the efficiency of the biomixture was evaluated through a multi-component approach that included: monitoring of CBF removal and production of CBF transformation products, mineralization of radioisotopically labeled carbofuran (14C-CBF) and changes in the toxicity of the matrix after the treatment (Daphnia magna acute immobilization test). Estimated half-lives of CBF in the biomixtures were 3.4 d and 8.1 d in GTS and GCS, respectively. The transformation products 3-hydroxycarbofuran and 3-ketocarbofuran were detected at the moment of CFN application, however their concentration continuously disappeared. Mineralization of 14C-CFN was also faster in GTS than GCS. The toxicological evaluation showed a complete toxicity removal in the biomixtures after 48 d of treatment. The composition of the GCS biomixture was optimized using a central composite design and response surface methodology. The design variables were the volumetric content of fungally pre-colonized rice husk and the volumetric ratio compost/soil. According to the response models, maximization of CFN removal and mineralization rate, and minimization in the accumulation of transformation products were obtained with an optimized biomixture of composition 30:43:27 (pre-colonized rice husk:compost:soil), which differs from the 50:25:25 composition commonly employed in BPS. Results suggest that fungal bioaugmentation may enhance the performance of biomixtures in CFN removal. Optimization reveals the importance of assessing new biomixture formulations in order to maximize their performance.

Keywords: bioaugmentation, biopurification systems, degradation, fungi, pesticides, toxicity

Procedia PDF Downloads 288