Search results for: area and volume
7346 Analysis of the Treatment Hemorrhagic Stroke in Multidisciplinary City Hospital №1 Nur-Sultan
Authors: M. G. Talasbayen, N. N. Dyussenbayev, Y. D. Kali, R. A. Zholbarysov, Y. N. Duissenbayev, I. Z. Mammadinova, S. M. Nuradilov
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Background. Hemorrhagic stroke is an acute cerebrovascular accident resulting from rupture of a cerebral vessel or increased permeability of the wall and imbibition of blood into the brain parenchyma. Arterial hypertension is a common cause of hemorrhagic stroke. Male gender and age over 55 years is a risk factor for intracerebral hemorrhage. Treatment of intracerebral hemorrhage is aimed at the primary pathophysiological link: the relief of coagulopathy and the control of arterial hypertension. Early surgical treatment can limit cerebral compression; prevent toxic effects of blood to the brain parenchyma. Despite progress in the development of neuroimaging data, the use of minimally invasive techniques, and navigation system, mortality from intracerebral hemorrhage remains high. Materials and methods. The study included 78 patients (62.82% male and 37.18% female) with a verified diagnosis of hemorrhagic stroke in the period from 2019 to 2021. The age of patients ranged from 25 to 80 years, the average age was 54.66±11.9 years. Demographic, brain CT data (localization, volume of hematomas), methods of treatment, and disease outcome were analyzed. Results. The retrospective analyze demonstrate that 78.2% of all patients underwent surgical treatment: decompressive craniectomy in 37.7%, craniotomy with hematoma evacuation in 29.5%, and hematoma draining in 24.59% cases. The study of the proportion of deaths, depending on the volume of intracerebral hemorrhage, shows that the number of deaths was higher in the group with a hematoma volume of more than 60 ml. Evaluation of the relationship between the time before surgery and mortality demonstrates that the most favorable outcome is observed during surgical treatment in the interval from 3 to 24 hours. Mortality depending on age did not reveal a significant difference between age groups. An analysis of the impact of the surgery type on mortality reveals that decompressive craniectomy with or without hematoma evacuation led to an unfavorable outcome in 73.9% of cases, while craniotomy with hematoma evacuation and drainage led to mortality only in 28.82% cases. Conclusion. Even though the multimodal approaches, the development of surgical techniques and equipment, and the selection of optimal conservative therapy, the question of determining the tactics of managing and treating hemorrhagic strokes is still controversial. Nevertheless, our experience shows that surgical intervention within 24 hours from the moment of admission and craniotomy with hematoma evacuation improves the prognosis of treatment outcomes.Keywords: hemorragic stroke, Intracerebral hemorrhage, surgical treatment, stroke mortality
Procedia PDF Downloads 1087345 Synthesis of Methanol through Photocatalytic Conversion of CO₂: A Green Chemistry Approach
Authors: Sankha Chakrabortty, Biswajit Ruj, Parimal Pal
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Methanol is one of the most important chemical products and intermediates. It can be used as a solvent, intermediate or raw material for a number of higher valued products, fuels or additives. From the last one decay, the total global demand of methanol has increased drastically which forces the scientists to produce a large amount of methanol from a renewable source to meet the global demand with a sustainable way. Different types of non-renewable based raw materials have been used for the synthesis of methanol on a large scale which makes the process unsustainable. In this circumstances, photocatalytic conversion of CO₂ into methanol under solar/UV excitation becomes a viable approach to give a sustainable production approach which not only meets the environmental crisis by recycling CO₂ to fuels but also reduces CO₂ amount from the atmosphere. Development of such sustainable production approach for CO₂ conversion into methanol still remains a major challenge in the current research comparing with conventional energy expensive processes. In this backdrop, the development of environmentally friendly materials, like photocatalyst has taken a great perspective for methanol synthesis. Scientists in this field are always concerned about finding an improved photocatalyst to enhance the photocatalytic performance. Graphene-based hybrid and composite materials with improved properties could be a better nanomaterial for the selective conversion of CO₂ to methanol under visible light (solar energy) or UV light. The present invention relates to synthesis an improved heterogeneous graphene-based photocatalyst with improved catalytic activity and surface area. Graphene with enhanced surface area is used as coupled material of copper-loaded titanium oxide to improve the electron capture and transport properties which substantially increase the photoinduced charge transfer and extend the lifetime of photogenerated charge carriers. A fast reduction method through H₂ purging has been adopted to synthesis improved graphene whereas ultrasonication based sol-gel method has been applied for the preparation of graphene coupled copper loaded titanium oxide with some enhanced properties. Prepared photocatalysts were exhaustively characterized using different characterization techniques. Effects of catalyst dose, CO₂ flow rate, reaction temperature and stirring time on the efficacy of the system in terms of methanol yield and productivity have been studied in the present study. The study shown that the newly synthesized photocatalyst with an enhanced surface resulting in a sustained productivity and yield of methanol 0.14 g/Lh, and 0.04 g/gcat respectively, after 3 h of illumination under UV (250W) at an optimum catalyst dosage of 10 g/L having 1:2:3 (Graphene: TiO₂: Cu) weight ratio.Keywords: renewable energy, CO₂ capture, photocatalytic conversion, methanol
Procedia PDF Downloads 1117344 Geometric Optimisation of Piezoelectric Fan Arrays for Low Energy Cooling
Authors: Alastair Hales, Xi Jiang
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Numerical methods are used to evaluate the operation of confined face-to-face piezoelectric fan arrays as pitch, P, between the blades is varied. Both in-phase and counter-phase oscillation are considered. A piezoelectric fan consists of a fan blade, which is clamped at one end, and an extremely low powered actuator. This drives the blade tip’s oscillation at its first natural frequency. Sufficient blade tip speed, created by the high oscillation frequency and amplitude, is required to induce vortices and downstream volume flow in the surrounding air. A single piezoelectric fan may provide the ideal solution for low powered hot spot cooling in an electronic device, but is unable to induce sufficient downstream airflow to replace a conventional air mover, such as a convection fan, in power electronics. Piezoelectric fan arrays, which are assemblies including multiple fan blades usually in face-to-face orientation, must be developed to widen the field of feasible applications for the technology. The potential energy saving is significant, with a 50% power demand reduction compared to convection fans even in an unoptimised state. A numerical model of a typical piezoelectric fan blade is derived and validated against experimental data. Numerical error is found to be 5.4% and 9.8% using two data comparison methods. The model is used to explore the variation of pitch as a function of amplitude, A, for a confined two-blade piezoelectric fan array in face-to-face orientation, with the blades oscillating both in-phase and counter-phase. It has been reported that in-phase oscillation is optimal for generating maximum downstream velocity and flow rate in unconfined conditions, due at least in part to the beneficial coupling between the adjacent blades that leads to an increased oscillation amplitude. The present model demonstrates that confinement has a significant detrimental effect on in-phase oscillation. Even at low pitch, counter-phase oscillation produces enhanced downstream air velocities and flow rates. Downstream air velocity from counter-phase oscillation can be maximally enhanced, relative to that generated from a single blade, by 17.7% at P = 8A. Flow rate enhancement at the same pitch is found to be 18.6%. By comparison, in-phase oscillation at the same pitch outputs 23.9% and 24.8% reductions in peak downstream air velocity and flow rate, relative to that generated from a single blade. This optimal pitch, equivalent to those reported in the literature, suggests that counter-phase oscillation is less affected by confinement. The optimal pitch for generating bulk airflow from counter-phase oscillation is large, P > 16A, due to the small but significant downstream velocity across the span between adjacent blades. However, by considering design in a confined space, counterphase pitch should be minimised to maximise the bulk airflow generated from a certain cross-sectional area within a channel flow application. Quantitative values are found to deviate to a small degree as other geometric and operational parameters are varied, but the established relationships are maintained.Keywords: piezoelectric fans, low energy cooling, power electronics, computational fluid dynamics
Procedia PDF Downloads 2237343 Deformed Wing Virus and Varroa Destructor in the Local Honey Bee Colonies Apis mellifera intermissa in Algeria
Authors: Noureddine Adjlane, Nizar Haddad
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Deformed Wing Virus (DWV) is considered as the most prevalent virus that dangerous the honeybee health worldwide today. In this study we aimed to evaluate the impact of the virus on honeybees (Apis mellifera intermissa) mortality in Algeria and we conducted the study on samples collected from the central area in the country. We used PCR for the diagnoses of the (DWV) in the diagnosis. The results had shown a high infestation in the sampled colonies and it represented 42% of the total sample. In this study, we found a clear role of both Varroa destructor mite and DWV on hive mortality in the experimented apiary. Further studies need to be conducted in order to give soled recommendations to the beekeepers, decision makers and stockholders of the Algerian beekeeping sector.Keywords: honey bee, DWV, Varroa destructor, mortality, prevalence, infestation
Procedia PDF Downloads 4587342 Understanding the Human Element in Cybersecurity: A Literature Review and Recommendations
Authors: Sadiq Nasir
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The need for strong cybersecurity measures has been brought to light by society's growing reliance on technology. Cybersecurity breaches continue, with the human aspect playing a crucial role, despite the availability of technology remedies. By analyzing the most recent findings in this area of research on awareness, attitudes, and behaviour, this literature review seeks to comprehend the human element in cybersecurity. A thorough overview of the most recent studies and gaps in the body of knowledge will be determined through a systematic examination of the literature. The paper indicates that in order to address the human component in cybersecurity, a socio-technical strategy is required, and it advocates for additional study in order to fully comprehend the consequences of various interventions. The findings of this study will increase our understanding of cybersecurity and have useful ramifications for companies wanting to strengthen their cybersecurity posture.Keywords: cybersecurity, cybersecurity awareness, human factor in security, human security
Procedia PDF Downloads 897341 Photocatalytic Conversion of Water/Methanol Mixture into Hydrogen Using Cerium/Iron Oxides Based Structures
Authors: Wael A. Aboutaleb, Ahmed M. A. El Naggar, Heba M. Gobara
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This research work reports the photocatalytic production of hydrogen from water-methanol mixture using three different 15% ceria/iron oxide catalysts. The catalysts were prepared by physical mixing, precipitation, and ultrasonication methods and labeled as catalysts A-C. The structural and texture properties of the obtained catalysts were confirmed by X-ray diffraction (XRD), BET-surface area analysis and transmission electron microscopy (TEM). The photocatalytic activity of the three catalysts towards hydrogen generation was then tested. Promising hydrogen productivity was obtained by the three catalysts however different gases compositions were obtained by each type of catalyst. Specifically, catalyst A had produced hydrogen mixed with CO₂ while the composite structure (catalyst B) had generated only pure H₂. In the case of catalyst C, syngas made of H₂ and CO was revealed, as a novel product, for the first time, in such process.Keywords: hydrogen production, water splitting, photocatalysts, clean energy
Procedia PDF Downloads 2427340 An Examination of Thai Tourists' Motivation Behavior and Perception of Cultural Heritage in Chiang Mai Province
Authors: Sujui Yang, Peeraya Somsak, Markus Blut
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This research examines the international tourists in Chiang Mai, Thailand. It aims to study non-Thai tourists’ of this region to better understand their behavior and motives influencing the choice of cultural heritage tourists in Chiang Mai, Thailand. The data includes questionnaires of 250 tourists in the study area. The most important motives influencing decisions choices are several concerning customers’ perspectives on tourist destinations in cultural heritage in Chiang Mai province. Thai tourists in Chiang Mai are single, 72.5 percent are in the age of 21-40 years old and 50% of sample group are from central and northern of Thailand. Tourists’ motives capture the factor loading as well as the corresponding show 5 components: relaxation motives, place/ physical motives, learning motives, image motives, and achievement motives.Keywords: tourists motives, cultural heritage, Chiang Mai, customers’ perspectives
Procedia PDF Downloads 3917339 Comparison between Transient Elastography (FibroScan) and Liver Biopsy for Diagnosis of Hepatic Fibrosis in Chronic Hepatitis C Genotype 4
Authors: Gamal Shiha, Seham Seif, Shahera Etreby, Khaled Zalata, Waleed Samir
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Background: Transient Elastography (TE; FibroScan®) is a non-invasive technique to assess liver fibrosis. Aim: To compare TE and liver biopsy in hepatitis C virus (HCV) patients, genotype IV and evaluate the effect of steatosis and schistosomiasis on FibroScan. Methods: The fibrosis stage (METAVIR Score) TE, was assessed in 519 patients. The diagnostic performance of FibroScan is assessed by calculating the area under the receiver operating characteristic curves (AUROCs). Results: The cut-off value of ≥ F2 was 8.55 kPa, ≥ F3 was 10.2 kPa and cirrhosis = F4 was 16.3 kPa. The positive predictive value and negative predictive value were 70.1% and 81.7% for the diagnosis of ≥ F2, 62.6% and 96.22% for F ≥ 3, and 27.7% and 100% for F4. No significant difference between schistosomiasis, steatosis degree and FibroScan measurements. Conclusion: Fibroscan could accurately predict liver fibrosis.Keywords: chronic hepatitis C, FibroScan, liver biopsy, liver fibrosis
Procedia PDF Downloads 4137338 Features of Composites Application in Shipbuilding
Authors: Valerii Levshakov, Olga Fedorova
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Specific features of ship structures, made from composites, i.e. simultaneous shaping of material and structure, large sizes, complicated outlines and tapered thickness have defined leading role of technology, integrating test results from material science, designing and structural analysis. Main procedures of composite shipbuilding are contact molding, vacuum molding and winding. Now, the most demanded composite shipbuilding technology is the manufacture of structures from fiberglass and multilayer hybrid composites by means of vacuum molding. This technology enables the manufacture of products with improved strength properties (in comparison with contact molding), reduction of production duration, weight and secures better environmental conditions in production area. Mechanized winding is applied for the manufacture of parts, shaped as rotary bodies – i.e. parts of ship, oil and other pipelines, deep-submergence vehicles hulls, bottles, reservoirs and other structures. This procedure involves processing of reinforcing fiberglass, carbon and polyaramide fibers. Polyaramide fibers have tensile strength of 5000 MPa, elastic modulus value of 130 MPa and rigidity of the same can be compared with rigidity of fiberglass, however, the weight of polyaramide fiber is 30% less than weight of fiberglass. The same enables to the manufacture different structures, including that, using both – fiberglass and organic composites. Organic composites are widely used for the manufacture of parts with size and weight limitations. High price of polyaramide fiber restricts the use of organic composites. Perspective area of winding technology development is the manufacture of carbon fiber shafts and couplings for ships. JSC ‘Shipbuilding & Shiprepair Technology Center’ (JSC SSTC) developed technology of dielectric uncouplers for cryogenic lines, cooled by gaseous or liquid cryogenic agents (helium, nitrogen, etc.) for temperature range 4.2-300 K and pressure up to 30 MPa – the same is used for separating components of electro physical equipment with different electrical potentials. Dielectric uncouplers were developed, the manufactured and tested in accordance with International Thermonuclear Experimental Reactor (ITER) Technical specification. Spiral uncouplers withstand operating voltage of 30 kV, direct-flow uncoupler – 4 kV. Application of spiral channel instead of rectilinear enables increasing of breakdown potential and reduction of uncouplers sizes. 95 uncouplers were successfully the manufactured and tested. At the present time, Russian the manufacturers of ship composite structures have started absorption of technology of manufacturing the same using automated prepreg laminating; this technology enables the manufacture of structures with improved operational specifications.Keywords: fiberglass, infusion, polymeric composites, winding
Procedia PDF Downloads 2397337 Ficus carica as Adsorbent for Removal of Phenol from Aqueous Solutions: Modeling and Optimization
Authors: Tizi Hayet, Berrama Tarek, Bounif Nadia
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Phenol and its derivatives are organic compounds utilized in the chemical industry. They are introduced into the environment by accidental spills and the illegal release of industrial and municipal wastewater. Phenols are organic intermediaries that are considered potential pollutants. Adsorption is one of the purification and separation techniques used in this area. Algeria annually produces 131000 tons of fig; therefore, a large amount of fig leaves is generated, and the conversion of this waste into adsorbent allows the valorization of agricultural residue. The main purpose of this present work is to describe an application of a statistical method for modeling and to optimize the conditions of the phenol adsorption from agricultural by-products, locally available (fig leaves). The best experimental performance of phenol elimination on the adsorbent was obtained with: Adsorbent concentration (X₂) = 200 mg L⁻¹; Initial concentration (X₃) = 150 mg L⁻¹; Speed agitation (X₁) = 300 rpm.Keywords: low-cost adsorbents, adsorption, fig leaves, phenol, factorial design
Procedia PDF Downloads 1177336 Sustainable Traditional Urban Design of the Old City of Ghadames
Authors: Hazem Bunkheila
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Ghadames is an oasis on the edge of the Sahara Desert in southwestern Libya at the border with Algeria and Tunisia. It is the oldest oasis in the world that provides a fascinating example of traditional urban in the desert environment. The urban of the small city is considered a genuine adaptation to the harsh desert climate. The historic city of Ghadames remained unaffected by the rapid after oil changes. That makes it a good field to study sustainable, vernacular, earth architecture and urban design. The aim of this paper is to investigate the urban structure, concept, and fabric of the old oasis. The research also surveys the environmental considerations in the city that shades the sustainable features in this traditional residential area. In addition, the paper addresses the modern applications in the new city of Ghadams and sides of success and failure compared to the traditional urban fabric.Keywords: dessert climate design, Ghadames, sustainable urban design, traditional urban design
Procedia PDF Downloads 3637335 The Use of Drones in Measuring Environmental Impacts of the Forest Garden Approach
Authors: Andrew J. Zacharias
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The forest garden approach (FGA) was established by Trees for the Future (TREES) over the organization’s 30 years of agroforestry projects in Sub-Saharan Africa. This method transforms traditional agricultural systems into highly managed gardens that produce food and marketable products year-round. The effects of the FGA on food security, dietary diversity, and economic resilience have been measured closely, and TREES has begun to closely monitor the environmental impacts through the use of sensors mounted on unmanned aerial vehicles, commonly known as 'drones'. These drones collect thousands of pictures to create 3-D models in both the visible and the near-infrared wavelengths. Analysis of these models provides TREES with quantitative and qualitative evidence of improvements to the annual above-ground biomass and leaf area indices, as measured in-situ using NDVI calculations.Keywords: agroforestry, biomass, drones, NDVI
Procedia PDF Downloads 1607334 Optimisation of Energy Harvesting for a Composite Aircraft Wing Structure Bonded with Discrete Macro Fibre Composite Sensors
Authors: Ali H. Daraji, Ye Jianqiao
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The micro electrical devices of the wireless sensor network are continuously developed and become very small and compact with low electric power requirements using limited period life conventional batteries. The low power requirement for these devices, cost of conventional batteries and its replacement have encouraged researcher to find alternative power supply represented by energy harvesting system to provide an electric power supply with infinite period life. In the last few years, the investigation of energy harvesting for structure health monitoring has increased to powering wireless sensor network by converting waste mechanical vibration into electricity using piezoelectric sensors. Optimisation of energy harvesting is an important research topic to ensure a flowing of efficient electric power from structural vibration. The harvesting power is mainly based on the properties of piezoelectric material, dimensions of piezoelectric sensor, its position on a structure and value of an external electric load connected between sensor electrodes. Larger surface area of sensor is not granted larger power harvesting when the sensor area is covered positive and negative mechanical strain at the same time. Thus lead to reduction or cancellation of piezoelectric output power. Optimisation of energy harvesting is achieved by locating these sensors precisely and efficiently on the structure. Limited published work has investigated the energy harvesting for aircraft wing. However, most of the published studies have simplified the aircraft wing structure by a cantilever flat plate or beam. In these studies, the optimisation of energy harvesting was investigated by determination optimal value of an external electric load connected between sensor electrode terminals or by an external electric circuit or by randomly splitting piezoelectric sensor to two segments. However, the aircraft wing structures are complex than beam or flat plate and mostly constructed from flat and curved skins stiffened by stringers and ribs with more complex mechanical strain induced on the wing surfaces. This aircraft wing structure bonded with discrete macro fibre composite sensors was modelled using multiphysics finite element to optimise the energy harvesting by determination of the optimal number of sensors, location and the output resistance load. The optimal number and location of macro fibre sensors were determined based on the maximization of the open and close loop sensor output voltage using frequency response analysis. It was found different optimal distribution, locations and number of sensors bounded on the top and the bottom surfaces of the aircraft wing.Keywords: energy harvesting, optimisation, sensor, wing
Procedia PDF Downloads 3047333 Catalytic Deoxygenation of Propionic Acid in the Vapour Phase
Authors: Hossein Bayahia, Mohammed Saad Motlaq Al-Gahmdi
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The gas-phase deoxygenation of propionic acid was investigated in the presence of Co-Mo catalysts in N2 or H2 flow at 200-400 °C. In the presence of N2 the main product was 3-pentanone with other deoxygenates and some light gases: ethane and ethene. Using H2 flow, the catalyst was active for decarboxylation and decarbonylation of acid and the yields of ethane and ethene. The decarboxylation and decarbonylation reactions increased with increasing temperature. Cobalt-molybdenum supported on alumina showed better performance than bulk catalyst, especially at 400 °C in the presence of N2 for the ketonisation of propionic acid to form 3-pentanone as the main product. Bulk and supported catalysts were characterized by surface area porosity (BET), thermogravimetric analysis (TGA) and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) of pyridine adsorption.Keywords: deoxygenation, propionic acid, gas-phase, catalyst
Procedia PDF Downloads 2877332 Effect of Particle Size on Alkali-Activation of Slag
Authors: E. Petrakis, V. Karmali, K. Komnitsas
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In this study grinding experiments were performed in a laboratory ball mill using Polish ferronickel slag in order to study the effect of the particle size on alkali activation and the properties of the produced alkali activated materials (AAMs). In this regard, the particle size distribution and the specific surface area of the grinding products in relation to grinding time were assessed. The experimental results show that products with high compressive strength, e.g. higher than 60 MPa, can be produced when the slag median size decreased from 39.9 μm to 11.9 μm. Also, finer fractions are characterized by higher reactivity and result in the production of AAMs with lower porosity and better mechanical properties.Keywords: alkali activation, compressive strength, grinding time, particle size distribution, slag, structural integrity
Procedia PDF Downloads 1397331 Electrical Load Estimation Using Estimated Fuzzy Linear Parameters
Authors: Bader Alkandari, Jamal Y. Madouh, Ahmad M. Alkandari, Anwar A. Alnaqi
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A new formulation of fuzzy linear estimation problem is presented. It is formulated as a linear programming problem. The objective is to minimize the spread of the data points, taking into consideration the type of the membership function of the fuzzy parameters to satisfy the constraints on each measurement point and to insure that the original membership is included in the estimated membership. Different models are developed for a fuzzy triangular membership. The proposed models are applied to different examples from the area of fuzzy linear regression and finally to different examples for estimating the electrical load on a busbar. It had been found that the proposed technique is more suited for electrical load estimation, since the nature of the load is characterized by the uncertainty and vagueness.Keywords: fuzzy regression, load estimation, fuzzy linear parameters, electrical load estimation
Procedia PDF Downloads 5447330 Polymer Nanocomposite Containing Silver Nanoparticles for Wound Healing
Authors: Patrícia Severino, Luciana Nalone, Daniele Martins, Marco Chaud, Classius Ferreira, Cristiane Bani, Ricardo Albuquerque
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Hydrogels produced with polymers have been used in the development of dressings for wound treatment and tissue revitalization. Our study on polymer nanocomposites containing silver nanoparticles shows antimicrobial activity and applications in wound healing. The effects are linked with the slow oxidation and Ag⁺ liberation to the biological environment. Furthermore, bacterial cell membrane penetration and metabolic disruption through cell cycle disarrangement also contribute to microbial cell death. The silver antimicrobial activity has been known for many years, and previous reports show that low silver concentrations are safe for human use. This work aims to develop a hydrogel using natural polymers (sodium alginate and gelatin) combined with silver nanoparticles for wound healing and with antimicrobial properties in cutaneous lesions. The hydrogel development utilized different sodium alginate and gelatin proportions (20:80, 50:50 and 80:20). The silver nanoparticles incorporation was evaluated at the concentrations of 1.0, 2.0 and 4.0 mM. The physico-chemical properties of the formulation were evaluated using ultraviolet-visible (UV-Vis) absorption spectroscopy, Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), and thermogravimetric (TG) analysis. The morphological characterization was made using transmission electron microscopy (TEM). Human fibroblast (L2929) viability assay was performed with a minimum inhibitory concentration (MIC) assessment as well as an in vivo cicatrizant test. The results suggested that sodium alginate and gelatin in the (80:20) proportion with 4 mM of AgNO₃ in the (UV-Vis) exhibited a better hydrogel formulation. The nanoparticle absorption spectra of this analysis showed a maximum band around 430 - 450 nm, which suggests a spheroidal form. The TG curve exhibited two weight loss events. DSC indicated one endothermic peak at 230-250 °C, due to sample fusion. The polymers acted as stabilizers of a nanoparticle, defining their size and shape. Human fibroblast viability assay L929 gave 105 % cell viability with a negative control, while gelatin presented 96% viability, alginate: gelatin (80:20) 96.66 %, and alginate 100.33 % viability. The sodium alginate:gelatin (80:20) exhibited significant antimicrobial activity, with minimal bacterial growth at a ratio of 1.06 mg.mL⁻¹ in Pseudomonas aeruginosa and 0.53 mg.mL⁻¹ in Staphylococcus aureus. The in vivo results showed a significant reduction in wound surface area. On the seventh day, the hydrogel-nanoparticle formulation reduced the total area of injury by 81.14 %, while control reached a 45.66 % reduction. The results suggest that silver-hydrogel nanoformulation exhibits potential for wound dressing therapeutics.Keywords: nanocomposite, wound healing, hydrogel, silver nanoparticle
Procedia PDF Downloads 1047329 Types of Motivation at a Rural University
Authors: Sandra Valdez-Hernández
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Motivation is one of the most important factors when teaching language. Most institutions at least in Mexico, pay low attention to the types of motivation students have when they are studying English; however, considering the motivation they have, may lead to better understanding about their needs and purposes for learning English and the professors may understand and focus on their interests for making them persist in action through the course. This topic has been widely investigated in different countries, but more research needs to be done in Mexico to shed light on this area of potential impact. The aim of this research is to focus on the types of motivation, intrinsic and extrinsic, instrumental and integrative and the attitudes students have about English language to identify aspects that are alike to other contexts and research areas based on the theory of Dörnyei (2013) and Gardner (2001). It was carried out at a Mexican University in a small village in Quintana Roo. The potential implications, the findings as well as the limitations are presented.Keywords: attides of motivation, factors of motivation, extrinsic and intrinsic motivation, instrumental and integrative motivation
Procedia PDF Downloads 927328 Acquisition of Murcian Lexicon and Morphology by L2 Spanish Immigrants: The Role of Social Networks
Authors: Andrea Hernandez Hurtado
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Research on social networks (SNs) -- the interactions individuals share with others has shed important light in helping to explain differential use of variable linguistic forms, both in L1s and L2s. Nevertheless, the acquisition of nonstandard L2 Spanish in the Region of Murcia, Spain, and how learners interact with other speakers while sojourning there have received little attention. Murcian Spanish (MuSp) was widely influenced by Panocho, a divergent evolution of Hispanic Latin, and differs from the more standard Peninsular Spanish (StSp) in phonology, morphology, and lexicon. For instance, speakers from this area will most likely palatalize diminutive endings, producing animalico [̩a.ni.ma.ˈli.ko] instead of animalito [̩a.ni.ma.ˈli.to] ‘little animal’. Because L1 speakers of the area produce and prefer salient regional lexicon and morphology (particularly the palatalized diminutive -ico) in their speech, the current research focuses on how international residents in the Region of Murcia use Spanish: (1) whether or not they acquire (perceptively and/or productively) any of the salient regional features of MuSp, and (2) how their SNs explain such acquisition. This study triangulates across three tasks -recognition, production, and preference- addressing both lexicon and morphology, with each task specifically created for the investigation of MuSp features. Among other variables, the effects of L1, residence, and identity are considered. As an ongoing dissertation research, data are currently being gathered through an online questionnaire. So far, 7 participants from multiple nationalities have completed the survey, although a minimum of 25 are expected to be included in the coming months. Preliminary results revealed that MuSp lexicon and morphology were successfully recognized by participants (p<.001). In terms of regional lexicon production (10.0%) and preference (47.5%), although participants showed higher percentages of StSp, results showed that international residents become aware of stigmatized lexicon and may incorporate it into their language use. Similarly, palatalized diminutives (production 14.2%, preference 19.0%) were present in their responses. The Social Network Analysis provided information about participants’ relationships with their interactants, as well as among them. Results indicated that, generally, when residents were more immersed in the culture (i.e., had more Murcian alters) they produced and preferred more regional features. This project contributes to the knowledge of language variation acquisition in L2 speakers, focusing on a stigmatized Spanish dialect and exploring how stigmatized varieties may affect L2 development. Results will show how L2 Spanish speakers’ language is affected by their stay in Murcia. This, in turn, will shed light on the role of SNs in language acquisition, the acquisition of understudied and marginalized varieties, and the role of immersion on language acquisition. As the first systematic account on the acquisition of L2 Spanish lexicon and morphology in the Region of Murcia, it lays important groundwork for further research on the connection between SNs and the acquisition of regional variants, applicable to Murcia and beyond.Keywords: international residents, L2 Spanish, lexicon, morphology, nonstandard language acquisition, social networks
Procedia PDF Downloads 787327 Optimisation of the Hydrometeorological-Hydrometric Network: A Case Study in Greece
Authors: E. Baltas, E. Feloni, G. Bariamis
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The operation of a network of hydrometeorological-hydrometric stations is basic infrastructure for the management of water resources, as well as, for flood protection. The assessment of water resources potential led to the necessity of adoption management practices including a multi-criteria analysis for the optimum design of the region’s station network. This research work aims at the optimisation of a new/existing network, using GIS methods. The planning of optimum network stations is based on the guidelines of international organizations such as World Meteorological Organization (WMO). The uniform spatial distribution of the stations, the drainage basin for the hydrometric stations and criteria concerning the low terrain slope, the accessibility to the stations and proximity to hydrological interest sites, were taken into consideration for its development. The abovementioned methodology has been implemented for two different areas the Florina municipality and the Argolis area in Greece, and comparison of the results has been conducted.Keywords: GIS, hydrometeorological, hydrometric, network, optimisation
Procedia PDF Downloads 2897326 The Role of University in High-Level Human Capital Cultivation in China’s West Greater Bay Area
Authors: Rochelle Yun Ge
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University has played an active role in the country’s development in China. There has been an increasing research interest on the development of higher education cooperation, talent cultivation and attraction, and innovation in the regional development. The Triple Helix model, which indicates that regional innovation and development can be engendered by collaboration among university, industry and government, is often adopted as research framework. The research using triple helix model emphasizes the active and often leading role of university in knowledge-based economy. Within this framework, universities are conceptualized as key institutions of knowledge production, transmission and transference potentially making critical contributions to regional development. Recent research almost uniformly consistent in indicating the high-level research labours (i.e., doctoral, post-doctoral researchers and academics) as important actors in the innovation ecosystem with their cross-geographical human capital and resources presented. In 2019, the development of the Guangdong-Hong Kong-Macao Greater Bay Area (GBA) was officially launched as an important strategy by the Chinese government to boost the regional development of the Pearl River Delta and to support the realization of “One Belt One Road” strategy. Human Capital formation is at the center of this plan. One of the strategic goals of the GBA development is set to evolve into an international educational hub and innovation center with high-level talents. A number of policies have been issued to attract and cultivate human resources in different GBA cities, in particular for the high-level R&D (research and development) talents such as doctoral and post-doctoral researchers. To better understand the development of high-level talents hub in the GBA, more empirical considerations should be given to explore the approaches of talents cultivation and attraction in the GBA. What remains to explore is the ways to better attract, train, support and retain these talents in the cross-systems context. This paper aims to investigate the role of university in human capital development under China’s national agenda of GBA integration through the lens of universities and actors. Two flagship comprehensive universities are selected to be the cases and 30 interviews with university officials, research leaders, post-doctors and doctoral candidates are used for analysis. In particular, we look at in what ways have universities aligned their strategies and practices to the Chinese government’s GBA development strategy? What strategies and practices have been developed by universities for the cultivation and attraction of high-level research labor? And what impacts the universities have made for the regional development? The main arguments of this research highlights the specific ways in which universities in smaller sub-regions can collaborate in high-level human capital formation and the role policy can play in facilitating such collaborations.Keywords: university, human capital, regional development, triple-helix model
Procedia PDF Downloads 1147325 Investigation of Length Effect on Power Conversion Efficiency of Perovskite Solar Cells Composed of ZnO Nanowires
Authors: W. S. Li, S. T. Yang, H. C. Cheng
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The power conversion efficiency (PCE) of the perovskite solar cells has been achieved by inserting vertically-aligned ZnO nanowires (NWs) between the cathode and the active layer and shows better solar cells performance. Perovskite solar cells have drawn significant attention due to the superb efficiency and low-cost fabrication process. In this experiment, ZnO nanowires are used as the electron transport layer (ETL) due to its low temperature process. The main idea of this thesis is utilizing the 3D structures of the hydrothermally-grown ZnO nanowires to increase the junction area to improve the photovoltaic performance of the perovskite solar cells. The infiltration and the surface coverage of the perovskite precursor solution changed as tuning the length of the ZnO nanowires. It is revealed that the devices with ZnO nanowires of 150 nm demonstrated the best PCE of 8.46 % under the AM 1.5G illumination (100 mW/cm2).Keywords: hydrothermally-grown ZnO nanowires, perovskite solar cells, low temperature process, pinholes
Procedia PDF Downloads 3337324 Numerical Analysis of Core-Annular Blood Flow in Microvessels at Low Reynolds Numbers
Authors: L. Achab, F. Iachachene
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In microvessels, red blood cells (RBCs) exhibit a tendency to migrate towards the vessel center, establishing a core-annular flow pattern. The core region, marked by a high concentration of RBCs, is governed by significantly non-Newtonian viscosity. Conversely, the annular layer, composed of cell-free plasma, is characterized by Newtonian low viscosity. This property enables the plasma layer to act as a lubricant for the vessel walls, efficiently reducing resistance to the movement of blood cells. In this study, we investigate the factors influencing blood flow in microvessels and the thickness of the annular plasma layer using a non-miscible fluids approach in a 2D axisymmetric geometry. The governing equations of an incompressible unsteady flow are solved numerically through the Volume of Fluid (VOF) method to track the interface between the two immiscible fluids. To model blood viscosity in the core region, we adopt the Quemada constitutive law which is accurately captures the shear-thinning blood rheology over a wide range of shear rates. Our results are then compared to an established theoretical approach under identical flow conditions, particularly concerning the radial velocity profile and the thickness of the annular plasma layer. The simulation findings for low Reynolds numbers, demonstrate a notable agreement with the theoretical solution, emphasizing the pivotal role of blood’s rheological properties in the core region in determining the thickness of the annular plasma layer.Keywords: core-annular flows, microvessels, Quemada model, plasma layer thickness, volume of fluid method
Procedia PDF Downloads 617323 International Trade, Food Security, and Climate Change in an Era of Liberal Trade
Authors: M. Barsa
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This paper argues that current liberal trade regimes have had the unfortunate effect of concentrating food production by area and by crop. While such hyper-specialization and standardization might be efficient under ordinary climate conditions, the increasing severity of climate shocks makes such a food production system especially vulnerable. Examining domestic US crop production, and the fact that similar patterns are evident worldwide, this paper explores the vulnerabilities of several major crops and suggests that the academic arguments surrounding increasing liberalization of trade are ill-suited to the climate challenges to come. Indeed, a case can be made that protectionist measures—especially by developing countries whose agricultural sectors are vulnerable to the cheap US and European exports—are increasingly necessary to scatter food production geographically and to retain a resilient diversity of crop varieties.Keywords: climate change, crop resilience, diversity, international trade
Procedia PDF Downloads 1327322 Juvenile Paget’s Disease(JPD) of Bone
Authors: Aftab Ahmed, Ghulam Mehboob
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The object of presentation is to highlight the importance of condition which is a very rare genetic disorder although Paget’s disease is common but its juvenile type is very rare and a late presentation due to very slow onset and lack of earlier standard management. We present a case of 25 years old male with a chronic history of bone pain and a slow onset of mild swelling, later on diagnosed as juvenile Paget disease of bone. Rarity of this condition with inaccessibility for standard health treatment can lead to a significant delay in presentation and its management. There have been 50 reported cases worldwide according to Genetic Home Reference. There is increased osteoclastic activity along with osteoblastic activity related to gene alteration and osteoprotegrin deficiency. Morbidity of disease is very significant which lead children to become immobilize.Keywords: juvenile, Paget’s disease, bone, Northern Area of Pakistan
Procedia PDF Downloads 3307321 Establishing the Optimum Location of a Single Tower Crane Using a Smart Mathematical Model
Authors: Yasser Abo El-Magd, Wael Fawzy Mohamed
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Due to the great development in construction and building field, there are many projects and huge works appeared which consume many construction materials. Accordingly, that causes difficulty in handling traditional transportation means (ordinary cranes) due to their limited capacity; there is an urgent need to use high capacity cranes such as tower cranes. However, with regard to their high expense, we have to take into consideration selecting what type of cranes to be utilized which has been discussed by many researchers. In this research, a proposed technique was created to select the suitable type of crane and the best place for crane erection, in addition to minimum radius for requested crane in order to minimize cost. To fulfill that target, a computer program is designed to numerate these problems, demonstrating an example explaining how to apply program and the result donated the best place.Keywords: tower crane, jib length, operating time, location, feasible area
Procedia PDF Downloads 2287320 Morphotectonic Analysis of Burkh Anticline, North of Bastak, Zagros
Authors: A. Afroogh, R. Ramazani omali, N. Hafezi Moghaddas, A. Nohegar
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The Burkh anticline with a length of 50 km and a width of 9 km is located 40 km to the north of Bastak in internal Fars zone in folded-trusted belt of Zagros. In order to assess the active tectonics in the area of study, morphometrical indexes such as V indexes (V), ratio of valley floor to valley width (Vf), the stream length-gradient ratio (Sl), channel sinuosity indexes (S), mountain front faceting indexes (F%) and mountain front sinuosity(Smf) have been studied. These investigations show that the activity is not equal in various sections of the length of Burkh anticline. The central part of this anticline is the most active one.Keywords: anticline, internal fars zone, tectonic, morohometrical indexes, folded-trusted belt
Procedia PDF Downloads 2547319 Cybercrime: International Police Cooperation with Europol
Authors: Daniel Suarez Alonso
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Cybercrime is a growing international threat and a challenge for law enforcement agencies and judicial systems worldwide. International cooperation is necessary to solve this problem because cybercrime knows no borders and often involves multiple jurisdictions, being related to organised crime. The purpose of this article is to analyse international cooperation in the investigation and prosecution of cybercrime, focusing on the framework of the Regulation of the European Union Agency for Law Enforcement Cooperation (EUROPOL), cooperation that takes place between police authorities from different countries. It examines the legal and operational mechanisms in place to facilitate international cooperation in Europe in this area and assesses their effectiveness in the fight against cybercrime. In addition, the study of a Spanish investigation where cooperation with EUROPOL took place will be examined, analyzing how international cooperation was carried out to investigate and track down criminals. Lessons learned from this case will be discussed and recommendations for improving international cooperation in the fight against cybercrime will be proposed.Keywords: Europol, international cooperation, cybercrime, computer crime, law
Procedia PDF Downloads 697318 Metal Contaminants in River Water and Human Urine after an Episode of Major Pollution by Mining Wastes in the Kasai Province of DR Congo
Authors: Remy Mpulumba Badiambile, Paul Musa Obadia, Malick Useni Mutayo, Jeef Numbi Mukanya, Patient Nkulu Banza, Tony Kayembe Kitenge, Erik Smolders, Jean-François Picron, Vincent Haufroid, Célestin Banza Lubaba Nkulu, Benoit Nemery
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Background: In July 2021, the Tshikapa river became heavily polluted by mining wastes from a diamond mine in neighboring Angola, leading to massive killing of fish, as well as disease and even deaths among residents living along the Tshikapa and Kasai rivers, a major contributory of the Congo river. The exact nature of the pollutants was unknown. Methods: In a cross-sectional study conducted in the city of Tshikapa in August 2021, we enrolled by opportunistic sampling 65 residents (11 children < 16y) living alongside the polluted rivers and 65 control residents (5 children) living alongside a non-affected portion of the Kasai river (upstream from the Tshikapa-Kasai confluence). We administered a questionnaire and obtained spot urine samples for measurements of thiocyanate (a metabolite of cyanide) and 26 trace metals (by ICP-MS). Metals (and pH) were also measured in samples of river water. Results: Participants from both groups consumed river water. In the area affected by the pollution, most participants had eaten dead fish. Prevalences of reported health symptoms were higher in the exposed group than among controls: skin rashes (52% vs 0%), diarrhea (40% vs 8%), abdominal pain (8% vs 3%), nausea (3% vs 0%). In polluted water, concentrations [median (range)] were only higher for nickel [(2.2(1.4–3.5)µg/L] and uranium [78(71–91)ng/L] than in non-polluted water [0.8(0.6–1.9)µg/L; 9(7–19)ng/L]. In urine, concentrations [µg/g creatinine, median(IQR)] were significantly higher in the exposed group than in controls for lithium [19.5(12.4–27.3) vs 6.9(5.9–12.1)], thallium [0.41(0.31–0.57) vs 0.19(0.16–0.39)], and uranium [0.026(0.013–0.037)] vs 0.012(0.006–0.024)]. Other elements did not differ between the groups, but levels were higher than reference values for several metals (including manganese, cobalt, nickel, and lead). Urinary thiocyanate concentrations did not differ. Conclusion: This study, after an ecological disaster in the DRC, has documented contamination of river water by nickel and uranium and high urinary levels of some trace metals among affected riverine populations. However, the exact cause of the massive fish kill and disease among residents remains elusive. The capacity to rapidly investigate toxic pollution events must be increased in the area.Keywords: metal contaminants, river water and human urine, pollution by mining wastes, DR Congo
Procedia PDF Downloads 1607317 Personnel Marketing as Perceived by HR Managers in Czech Republic: Results of a Qualitative Research Study
Authors: Lukáš Mazánek, Zdeňka Konečná
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The article is devoted to the area of personnel marketing. A comprehensive review of scientific literature and articles published predominantly in personnel-oriented journals was carried out, followed by a qualitative exploratory research with the aim to explore and explain the perception of personnel marketing. Due to the lack of research in this field in Czech Republic, we have focused on Czech HR managers, more specifically, on how they understand the tasks of personnel marketing, which tools they use and whether the companies they work for try to be a preferred employer. The answers from our respondents were used to help us determine what is important within this field. All of the respondents strive to be a preferred employer and try to achieve it by using an extensive range of marketing tools. The most frequently used tools are advertising, job fairs presentations, employee care and employer brand promotion.Keywords: Czech Republic, personnel marketing, preferred employer, qualitative research study
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