Search results for: personalized medicine application

Authors: Jessica P. Fiorotti, Maria C. Freitas, Caio J. B. Coutinho-Rodrigues, Mariana G. Camargo, Emily S. Mesquita, Amanda R. C. Corval, Ricardo O. B. Bitencourt, Allan F. Marciano, Diva D. Spadacci-Morena, Patricia S. Golo, Isabele C. Angelo, Vania R. E. P. Bittencourt

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The bovine tick, Rhipicephalus microplus, is an arthropod of great importance in veterinary medicine leading to anemia, weight loss, animals' leather depreciation and also acting as a vector of many pathogens. In this way, the parasitism causes a loss of 3.24 billion dollars per year in Brazil. Knowingly, entomopathogenic fungi act as natural controller of some arthropods, acting mainly by active penetration through the cuticle. However, it can also act on the hemolymph and through the production of mycotoxins. Hemocytes are responsible for the cellular immune response and participate in the processes of phagocytosis, nodulation and encapsulation and may undergo changes when challenged by pathogens. The aim of the present study was to evaluate changes in R. microplus hemocytes after inoculation of Metarhizium robertsii using transmission electron microscopy. The isolate ARSEF 2575 and 200 engorged R. microplus females were used. The groups were divided into control, in which the females were inoculated with 5 μL of sterile distilled water solution and 0.1% Tween 80, and a group inoculated with 5 μL of fungal suspension at the concentration of 10⁷ conidia mL⁻¹. The experiment was performed in duplicate and each group contained 50 females. Twenty-four hours after fungal inoculation, hemolymph was collected through the cuticle dorsal surface perforation of the tick females. After collection, the hemolymph samples were centrifuged at 500 x g for 3 minutes at 4 °C, the plasma was discarded and the hemocyte pellet was resuspended in 50 μl PBS. The suspension material was fixed in 2% glutaraldehyde in Millonig buffer for three hours. After fixation, the material was centrifuged at 500 x g for 3 minutes, the supernatant was discarded and the cells were resuspended in a wash solution. Subsequently, the cells were post-fixed with 1% osmium tetroxide in phosphate buffer for one hour at room temperature and dehydrated in increasing concentrations of ethanol, and then embedded in Epon resin. The ultrathin sections were examined under the LEO EM 906E transmission electron microscopy at 80kV. The ultrastructural results revealed that.in control group, the cells were considered intact, in which the granulocytes were observed with granules of different electrodensities, intact mitochondria and cytoplasm without vacuolization. In addition, granulocytes showed plasma membrane projections similar to pseudopodia. Plasmatocytes presented as irregularly shaped cells, with the eccentric nucleus, agranular cytoplasm and some cells presented pseudopodia. Nevertheless, in the group exposed to the fungus, most of the cells presented in degeneration. The granulocytes found had fewer granules in the cytoplasm and more vacuoles. Plasmatocytes, after treatment, presented many vacuoles also in the cytoplasm and the lysosomes presented great amount of electrodense material in their interior. Thus, the results suggest that the fungus has a depressant action in the immune system of the tick, not only by the cell degranulation, but also suggesting that this leads to morphological changes in the hemocytes and may even trigger processes such as phagocytosis.

Keywords: bovine tick, cellular defense, entomopathogenic fungi, immune response

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Authors: Kisik Song, Sungjoo Lee

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With the growing importance of intangible assets recently, the impact of patent infringement on the business of a company has become more evident. Accordingly, it is essential for firms to estimate the risk of patent infringement risk before developing a technology and create new technology ideas to avoid the risk. Recognizing the needs, several attempts have been made to help develop new technology opportunities and most of them have focused on identifying emerging vacant technologies from patent analysis. In these studies, the IPC (International Patent Classification) system or keywords from text-mining application to patent documents was generally used to define vacant technologies. Unlike those studies, this study adopted F-term, which classifies patent documents according to the technical features of the inventions described in them. Since the technical features are analyzed by various perspectives by F-term, F-term provides more detailed information about technologies compared to IPC while more systematic information compared to keywords. Therefore, if well utilized, it can be a useful guideline to create a new technology idea. Recognizing the potential of F-term, this paper aims to suggest a novel approach to developing new technology ideas to avoid patent infringement based on F-term. For this purpose, we firstly collected data about F-term and then applied text-mining to the descriptions about classification criteria and attributes. From the text-mining results, we could identify other technologies with similar technical features of the existing one, the patented technology. Finally, we compare the technologies and extract the technical features that are commonly used in other technologies but have not been used in the existing one. These features are presented in terms of “purpose”, “function”, “structure”, “material”, “method”, “processing and operation procedure” and “control means” and so are useful for creating new technology ideas that help avoid infringing patent rights of other companies. Theoretically, this is one of the earliest attempts to adopt F-term to patent analysis; the proposed methodology can show how to best take advantage of F-term with the wealth of technical information. In practice, the proposed methodology can be valuable in the ideation process for successful product and service innovation without infringing the patents of other companies.

Keywords: patent infringement, new technology ideas, patent analysis, F-term

Procedia PDF Downloads 262

Authors: Suleiman Garba, Haruna Ishaku

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Information and communication technology (ICT) includes any communication device encompassing: radio, television, cellular phones, computer, satellite systems and so on, as well as the various services and applications associated with them. The significance of ICT cannot be over-emphasized in education. The teaching and learning processes have integrated with the application of ICTs for effectiveness and enhancement of academic performance among the students. Today, as the educational sector is faced with series of changes and reforms, it was noted that the problem of information technology illiteracy was a serious one among the schools’ teachers in the country as it cuts across primary, secondary schools and tertiary institutions. This study investigated the impact of ICT on the academic performance of senior secondary schools students in Gwagwalada Area Council of Federal Capital Territory (FCT), Abuja. A sample of 120 SSS III students was involved in the study. They were selected by using simple random sampling technique. A questionnaire was developed and validated through expert judgement and reliability co-efficient of 0.81 was obtained. It was used to gather relevant data from the respondents. Findings revealed that there was positive impact of ICT on academic performance of senior secondary schools students. The findings indicated the causes of poor academic performance among the students as lack of qualified teachers to teach in schools, peer group influence, and bullying. Significantly, the findings revealed that ICT had a positive impact on students’ academic performance. The null hypotheses were tested using t-test at 0.05 level of significance. It was discovered that there was significant difference between male and female secondary schools’ students' impact of ICT on academic performance in Gwagawalada Area Council of FCT-Abuja. Based on these findings, some recommendations were made which include: adequate funds should be provided towards procurement of ICT resources, relevant textbooks to enhance students’ active participation in learning processes and students should be provided with internet accessibility at inexpensive rate so as to create a platform for accessing useful information in the pursuit of academic excellence.

Keywords: academic performance, impact, information communication technology, schools, students

Procedia PDF Downloads 214

Authors: Tarcisio F. Leao, Bruno Utiyama, Jeison Fonseca, Eduardo Bock, Aron Andrade

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This work presents a blood flow estimator based in Look-Up-Table (LUT) for control of Left Ventricular Assist Device (LVAD). This device has been used as bridge to transplantation or as destination therapy to treat patients with heart failure (HF). Destination Therapy application requires a high performance LVAD; thus, a stable control is important to keep adequate interaction between heart and device. LVAD control provides an adequate cardiac output while sustaining an appropriate flow and pressure blood perfusion, also described as physiologic control. Because thrombus formation and system reliability reduction, sensors are not desirable to measure these variables (flow and pressure blood). To achieve this, control systems have been researched to estimate blood flow. LVAD used in the study is composed by blood centrifugal pump, control, and power supply. This technique used pump and actuator (motor) parameters of LVAD, such as speed and electric current. Estimator relates electromechanical torque (motor or actuator) and hydraulic power (blood pump) via LUT. An in vitro Mock Loop was used to evaluate deviations between blood flow estimated and actual. A solution with glycerin (50%) and water was used to simulate the blood viscosity with hematocrit 45%. Tests were carried out with variation hematocrit: 25%, 45% and 58% of hematocrit, or 40%, 50% and 60% of glycerin in water solution, respectively. Test with bovine blood was carried out (42% hematocrit). Mock Loop is composed: reservoir, tubes, pressure and flow sensors, and fluid (or blood), beyond LVAD. Estimator based in LUT is patented, number BR1020160068363, in Brazil. Mean deviation is 0.23 ± 0.07 L/min for mean flow estimated. Larger mean deviation was 0.5 L/min considering hematocrit variation. This estimator achieved deviation adequate for physiologic control implementation. Future works will evaluate flow estimation performance in control system of LVAD.

Keywords: blood pump, flow estimator, left ventricular assist device, look-up-table

Procedia PDF Downloads 177

Authors: Ju-Hong Lee, Ching-Wei Liao

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Owing to close antenna spacing between antenna sensors within a compact space, a part of data in one antenna sensor would outflow to other antenna sensors when the antenna sensors in an antenna array operate simultaneously. This phenomenon is called mutual coupling effect (MCE). It has been shown that the performance of antenna array systems can be degraded when the antenna sensors are in close proximity. Especially, in a systems equipped with massive antenna sensors, the degradation of beamforming performance due to the MCE is significantly inevitable. Moreover, it has been shown that even a small angle error between the true direction angle of the desired signal and the steering angle deteriorates the effectiveness of an array beamforming system. However, the true direction vector of the desired signal may not be exactly known in some applications, e.g., the application in land mobile-cellular wireless systems. Therefore, it is worth developing robust techniques to deal with the problem due to the MCE and steering angle error for array beamforming systems. In this paper, we present an efficient technique for performing adaptive beamforming with robust capabilities against the MCE and the steering angle error. Only the data vector received by an antenna array is required by the proposed technique. By using the received array data vector, a correlation matrix is constructed to replace the original correlation matrix associated with the received array data vector. Then, the mutual coupling matrix due to the MCE on the antenna array is estimated through a recursive algorithm. An appropriate estimate of the direction angle of the desired signal can also be obtained during the recursive process. Based on the estimated mutual coupling matrix, the estimated direction angle, and the reconstructed correlation matrix, the proposed technique can effectively cure the performance degradation due to steering angle error and MCE. The novelty of the proposed technique is that the implementation procedure is very simple and the resulting adaptive beamforming performance is satisfactory. Simulation results show that the proposed technique provides much better beamforming performance without requiring complicated complexity as compared with the existing robust techniques.

Keywords: adaptive beamforming, mutual coupling effect, recursive algorithm, steering angle error

Procedia PDF Downloads 319

Authors: Shuo Li, Yannick Coffinier, Chann Lagadec, Fabrizio Cleri, Katsuhiko Nishiguchi, Akira Fujiwara, Soo Hyeon Kim, Nicolas Clément

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The need for single cell detection and analysis techniques has increased in the past decades because of the heterogeneity of individual living cells, which increases the complexity of the pathogenesis of malignant tumors. In the search for early cancer detection, high-precision medicine and therapy, the technologies most used today for sensitive detection of target analytes and monitoring the variation of these species are mainly including two types. One is based on the identification of molecular differences at the single-cell level, such as flow cytometry, fluorescence-activated cell sorting, next generation proteomics, lipidomic studies, another is based on capturing or detecting single tumor cells from fresh or fixed primary tumors and metastatic tissues, and rare circulating tumors cells (CTCs) from blood or bone marrow, for example, dielectrophoresis technique, microfluidic based microposts chip, electrochemical (EC) approach. Compared to other methods, EC sensors have the merits of easy operation, high sensitivity, and portability. However, despite various demonstrations of low limits of detection (LOD), including aptamer sensors, arrayed EC sensors for detecting single-cell have not been demonstrated. In this work, a new technique based on 20-nm-thick nanopillars array to support cells and keep them at ideal recognition distance for redox-labeled aptamers grafted on the surface. The key advantages of this technology are not only to suppress the false positive signal arising from the pressure exerted by all (including non-target) cells pushing on the aptamers by downward force but also to stabilize the aptamer at the ideal hairpin configuration thanks to a confinement effect. With the first implementation of this technique, a LOD of 13 cells (with5.4 μL of cell suspension) was estimated. In further, the nanosupported cell technology using redox-labeled aptasensors has been pushed forward and fully integrated into a single-cell electrochemical aptasensor array. To reach this goal, the LOD has been reduced by more than one order of magnitude by suppressing parasitic capacitive electrochemical signals by minimizing the sensor area and localizing the cells. Statistical analysis at the single-cell level is demonstrated for the recognition of cancer cells. The future of this technology is discussed, and the potential for scaling over millions of electrodes, thus pushing further integration at sub-cellular level, is highlighted. Despite several demonstrations of electrochemical devices with LOD of 1 cell/mL, the implementation of single-cell bioelectrochemical sensor arrays has remained elusive due to their challenging implementation at a large scale. Here, the introduced nanopillar array technology combined with redox-labeled aptamers targeting epithelial cell adhesion molecule (EpCAM) is perfectly suited for such implementation. Combining nanopillar arrays with microwells determined for single cell trapping directly on the sensor surface, single target cells are successfully detected and analyzed. This first implementation of a single-cell electrochemical aptasensor array based on Brownian-fluctuating redox species opens new opportunities for large-scale implementation and statistical analysis of early cancer diagnosis and cancer therapy in clinical settings.

Keywords: bioelectrochemistry, aptasensors, single-cell, nanopillars

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Authors: Shishay Kidanu, Abdullah Alhaj

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Sinkholes in the karst terrain of Greene County, Missouri, pose significant geohazards, imposing challenges on construction and infrastructure development, with potential threats to lives and property. To address these issues, understanding the influencing factors and modeling sinkhole susceptibility is crucial for effective mitigation through strategic changes in land use planning and practices. This study utilizes geographic information system (GIS) software to collect and process diverse data, including topographic, geologic, hydrogeologic, and anthropogenic information. Nine key sinkhole influencing factors, ranging from slope characteristics to proximity to geological structures, were carefully analyzed. The Frequency Ratio method establishes relationships between attribute classes of these factors and sinkhole events, deriving class weights to indicate their relative importance. Weighted integration of these factors is accomplished using the Analytic Hierarchy Process (AHP) and the Weighted Linear Combination (WLC) method in a GIS environment, resulting in a comprehensive sinkhole susceptibility index (SSI) model for the study area. Employing Jenk's natural break classifier method, the SSI values are categorized into five distinct sinkhole susceptibility zones: very low, low, moderate, high, and very high. Validation of the model, conducted through the Area Under Curve (AUC) and Sinkhole Density Index (SDI) methods, demonstrates a robust correlation with sinkhole inventory data. The prediction rate curve yields an AUC value of 74%, indicating a 74% validation accuracy. The SDI result further supports the success of the sinkhole susceptibility model. This model offers reliable predictions for the future distribution of sinkholes, providing valuable insights for planners and engineers in the formulation of development plans and land-use strategies. Its application extends to enhancing preparedness and minimizing the impact of sinkhole-related geohazards on both infrastructure and the community.

Keywords: sinkhole, GIS, analytical hierarchy process, frequency ratio, susceptibility, Missouri

Procedia PDF Downloads 69

Authors: Masoumeh Ghorbania, Falk Liebnerb, Hendrikus W.G. van Herwijnenc, Johannes Konnertha

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Phenol formaldehyde (PF) resins are widely used as wood adhesives for variety of industrial products such as plywood, laminated veneer lumber and others. Lignin as a main constituent of wood has become well-known as a potential substitute for phenol in PF adhesives because of their structural similarity. During the last decades numerous research approaches have been carried out to substitute phenol with pulping-derived lignin, whereby the lower reactivity of resins synthesized with shares of lignin seem to be one of the major challenges. This work reports about a systematic screening of different types of lignin (plant origin and pulping process) for their suitability to replace phenol in phenolic resins. Lignin from different plant sources (softwood, hardwood and grass) were used, as these should differ significantly in their reactivity towards formaldehyde of their reactive phenolic core units. Additionally a possible influence of the pulping process was addressed by using the different types of lignin from soda, kraft, and organosolv process and various lignosulfonates (sodium, ammonium, calcium, magnesium). To determine the influence of lignin on the adhesive performance beside others the rate of viscosity development, bond strength development of varying hot pressing time and other thermal properties were investigated. To evaluate the performance of the cured end product, a few selected properties were studied at the example of solid wood-adhesive bond joints, compact panels and plywood. As main results it was found that lignin significantly accelerates the viscosity development in adhesive synthesis. Bonding strength development during curing of adhesives decelerated for all lignin types, while this trend was least for pine kraft lignin and spruce sodium lignosulfonate. However, the overall performance of the products prepared with the latter adhesives was able to fulfill main standard requirements, even after exposing the products to harsh environmental conditions. Thus, a potential application can be considered for processes where reactivity is less critical but adhesive cost and product performance is essential.

Keywords: phenol formaldehyde resin, lignin phenol formaldehyde resin, ABES, DSC

Procedia PDF Downloads 233

Authors: Naima Bouslah, Leila Bounabi, Farid Ouazib, Nabila Haddadine

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Conventional release dosage forms are known to provide an immediate release of the drug. Controlling the rate of drug release from polymeric matrices is very important for a number of applications, particularly in the pharmaceutical area. Hydrogels are polymers in three-dimensional network arrangement, which can absorb and retain large amounts of water without dissolution. They have been frequently used to develop controlled released formulations for oral administration because they can extend the duration of drug release and thus reduce dose to be administrated improving patient compliance. Tramadol is an opioid pain medication used to treat moderate to moderately severe pain. When taken as an immediate-release oral formulation, the onset of pain relief usually occurs within about an hour. In the present work, we synthesized pH-responsive hydrogels of (hydroxyl ethyl methacrylate-co-acrylic acid), (HEMA-AA) for control drug delivery of tramadol in the gastro-intestinal tractus. The hydrogels with different acrylic acid content, were synthesized by free radical polymerization and characterized by FTIR spectroscopy, X ray diffraction analysis (XRD), differential scanning calorimetry (DSC) and thermo gravimetric analysis (TGA). FTIR spectroscopy has shown specific hydrogen bonding interactions between the carbonyl groups of the hydrogels and hydroxyl groups of tramadol. Both the XRD and DSC studies revealed that the introduction of tramadol in the hydrogel network induced the amorphization of the drug. The swelling behaviour, absorptive kinetics and the release kinetics of tramadol in simulated gastric fluid (pH 1.2) and in simulated intestinal fluid (pH 7.4) were also investigated. The hydrogels exhibited pH-responsive behavior in the swelling study. The (HEMA-AA) hydrogel swelling was much higher in pH =7.4 medium. The tramadol release was significantly increased when pH of the medium was changed from simulated gastric fluid (pH 1.2) to simulated intestinal fluid (pH 7.4). Using suitable mathematical models, the apparent diffusional coefficients and the corresponding kinetic parameters have been calculated.

Keywords: biopolymres, drug delivery, hydrogels, tramadol

Procedia PDF Downloads 353

Authors: Sladjana Popovic

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The concept of vertical space urbanization, defined in English as "air rights development," can be considered a mechanism for the development of public spaces in urban areas of high density. A chronological overview of the transformation of space within the vertical projection of the existing traffic infrastructure that penetrates through the central areas of a city is given in this paper through the analysis of two illustrative case studies: more advanced and recent - "Plot 13" in Boston, and less well-known European example of structures erected above highways throughout Italy - the "Pavesi auto grill" chain. The backbone of this analysis is the examination of the possibility of yielding air rights within the vertical projection of public structures in the two examples by considering the factors that would enable its potential application in capitals in Southeastern Europe. The cession of air rights in the Southeastern Europe region, as a phenomenon, has not been a recognized practice in urban planning. In a formal sense, legal and physical feasibility can be seen to some extent in local models of structures built above protected historical heritage (i.e., archaeological sites); however, the mechanisms of the legal process of assigning the right to use and develop air rights above public structures is not a recognized concept. The goal of the analysis is to shed light on the influence of institutional participants in the implementation of innovative solutions for vertical urbanization, as well as strategic planning mechanisms in public-private partnership models that would enable the implementation of the concept in the region. The main question is whether the manipulation of the vertical projection of space could provide for innovative urban solutions that overcome the deficit and excessive use of the available construction land, particularly above the dominant public spaces and traffic infrastructure that penetrate central parts of a city. Conclusions reflect upon vertical urbanization that can bridge the spatial separation of the city, reduce noise pollution and contribute to more efficient urban planning along main transportation corridors.

Keywords: air rights development, innovative urbanism, public-private partnership, transport infrastructure, vertical urbanization

Procedia PDF Downloads 67

Authors: R. Meier, M. Pander

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In accordance with the industry 4.0 concept, manufacturing process steps as well as the materials themselves are going to be more and more digitalized within the next years. The “digital twin” representing the simulated and measured dataset of the (semi-finished) product can be used to control and optimize the individual processing steps and help to reduce costs and expenditure of time in product development, manufacturing, and recycling. In the present work, two material characterization methods based on Lamb waves were evaluated and compared. For demonstration purpose, both methods were shown at a standard industrial product - copper ribbons, often used in photovoltaic modules as well as in high-current microelectronic devices. By numerical approximation of the Rayleigh-Lamb dispersion model on measured phase velocities second order elastic constants (Young’s modulus, Poisson’s ratio) were determined. Furthermore, the effective third order elastic constants were evaluated by applying elastic, “non-destructive”, mechanical stress on the samples. In this way, small microstructural variations due to mechanical preconditioning could be detected for the first time. Both methods were compared with respect to precision and inline application capabilities. Microstructure of the samples was systematically varied by mechanical loading and annealing. Changes in the elastic ultrasound transport properties were correlated with results from microstructural analysis and mechanical testing. In summary, monitoring the elastic material properties of plate-like structures using Lamb waves is valuable for inline and non-destructive material characterization and manufacturing process control. Second order elastic constants analysis is robust over wide environmental and sample conditions, whereas the effective third order elastic constants highly increase the sensitivity with respect to small microstructural changes. Both Lamb wave based characterization methods are fitting perfectly into the industry 4.0 concept.

Keywords: lamb waves, industry 4.0, process control, elasticity, acoustoelasticity, microstructure

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Authors: Dewi Retno Sari Saputro, Purnami Widyaningsih, Hendrika Handayani

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Extreme data on an observation can occur due to unusual circumstances in the observation. The data can provide important information that can’t be provided by other data so that its existence needs to be further investigated. The method for obtaining extreme data is one of them using maxima block method. The distribution of extreme data sets taken with the maxima block method is called the distribution of extreme values. Distribution of extreme values is Gumbel distribution with two parameters. The parameter estimation of Gumbel distribution with maximum likelihood method (ML) is difficult to determine its exact value so that it is necessary to solve the approach. The purpose of this study was to determine the parameter estimation of Gumbel distribution with quasi-Newton BFGS method. The quasi-Newton BFGS method is a numerical method used for nonlinear function optimization without constraint so that the method can be used for parameter estimation from Gumbel distribution whose distribution function is in the form of exponential doubel function. The quasi-New BFGS method is a development of the Newton method. The Newton method uses the second derivative to calculate the parameter value changes on each iteration. Newton's method is then modified with the addition of a step length to provide a guarantee of convergence when the second derivative requires complex calculations. In the quasi-Newton BFGS method, Newton's method is modified by updating both derivatives on each iteration. The parameter estimation of the Gumbel distribution by a numerical approach using the quasi-Newton BFGS method is done by calculating the parameter values that make the distribution function maximum. In this method, we need gradient vector and hessian matrix. This research is a theory research and application by studying several journals and textbooks. The results of this study obtained the quasi-Newton BFGS algorithm and estimation of Gumbel distribution parameters. The estimation method is then applied to daily rainfall data in Purworejo District to estimate the distribution parameters. This indicates that the high rainfall that occurred in Purworejo District decreased its intensity and the range of rainfall that occurred decreased.

Keywords: parameter estimation, Gumbel distribution, maximum likelihood, broyden fletcher goldfarb shanno (BFGS)quasi newton

Procedia PDF Downloads 318

Authors: Shan Huang, Guanjun Huang, Yongjun Zeng, Haiyuan Wang

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The impacts of whole-growth warming on grain yield and quality in double rice cropping systems still remain largely unknown. In this study, a two-year field whole-growth warming experiment was conducted with two inbred indica rice cultivars (Zhongjiazao 17 and Xiangzaoxian 45) for early season and two hybrid indica rice cultivars (Wanxiangyouhuazhan and Tianyouhuazhan) for late season. The results showed that whole-growth warming did not affect early rice yield but significantly decreased late rice yield, which was caused by the decreased grain weight that may be related to the increased plant respiration and reduced translocation of dry matter accumulated during the pre-heading phase under warming. Whole-growth warming improved the milling quality of late rice but decreased that of early rice; however, the chalky rice rate and chalkiness degree were increased by 20.7% and 33.9% for early rice and 37.6 % and 51.6% for late rice under warming, respectively. We found that the crude protein content of milled rice was significantly increased by warming in both early and late rice, which would result in deterioration of eating quality. Besides, compared with the control treatment, the setback of late rice was significantly reduced by 17.8 % under warming, while that of early rice was not significantly affected by warming. These results suggest that the negative impacts of whole-growth warming on grain quality may be more severe in early rice than in late rice. Therefore, adaptation in both rice breeding and agronomic practices is needed to alleviate climate warming on the production of a double rice cropping system. Climate-smart agricultural practices ought to be implemented to mitigate the detrimental effects of warming on rice grain quality. For instance, fine-tuning the application rate and timing of inorganic nitrogen fertilizers, along with the introduction of organic amendments and the cultivation of heat-tolerant rice varieties, can help reduce the negative impact of rising temperatures on rice quality. Furthermore, to comprehensively understand the influence of climate warming on rice grain quality, future research should encompass a wider range of rice cultivars and experimental sites.

Keywords: climate warming, double rice cropping, dry matter, grain quality, grain yield

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Authors: Anna S. Tolkacheva, Sergey N. Shkerin, Kirill G. Zemlyanoi, Olga G. Reznitskikh, Pavel D. Khavlyuk

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Calcium oxovanadates with garnet related structure are multifunctional oxides in various fields like photoluminescence, microwave dielectrics, and magneto-dielectrics. For example, vanadate garnets are self-luminescent compounds. They attract attention as RE-free broadband excitation and emission phosphors and are candidate materials for UV-based white light-emitting diodes (WLEDs). Ca₅M₄(VO₄)₆ (M = Mg, Zn, Co, Ni, Mn) compounds are also considered promising for application in microwave devices as substrate materials. However, the relation between their structure, composition and physical/chemical properties remains unclear. Given the above-listed observations, goals of this study are to synthesise Ca₅M₄(VO₄)₆ (M = Mg, Zn, Ni) and to study their thermal and electrical properties. Solid solutions Ca₅Mg₄₋ₓMₓ(VO₄)₆ (0 ≤ x ≤ 4) where M is Zn and Ni have been synthesized by sol-gel method. The single-phase character of the final products was checked by powder X-ray diffraction on a Rigaku D/MAX-2200 X-ray diffractometer using Cu Kα radiation in the 2θ range from 15° to 70°. The dependence of thermal properties on chemical composition of solid solutions was studied using simultaneous thermal analyses (DSC and TG). Thermal analyses were conducted in a Netzch simultaneous analyser STA 449C Jupiter, in Ar atmosphere, in temperature range from 25 to 1100°C heat rate was 10 K·min⁻¹. Coefficients of thermal expansion (CTE) were obtained by dilatometry measurements in air up to 800°C using a Netzsch 402PC dilatometer; heat rate was 1 K·min⁻¹. Impedance spectra were obtained via the two-probe technique with an impedance meter Parstat 2273 in air up to 700°C with the variation of pH₂O from 0.04 to 3.35 kPa. Cation deficiency in Ca and Mg sublattice under the substitution of MgO with ZnO up to 1/6 was observed using Rietveld refinement of the crystal structure. Melting point was found to decrease with x changing from 0 to 4 in Ca₅Mg₄₋ₓMₓ(VO₄)₆ where M is Zn and Ni. It was observed that electrical conductivity does not depend on air humidity. The reported study was funded by the RFBR Grant No. 17–03–01280. Sample attestation was carried out in the Shared Access Centers at the IHTE UB RAS.

Keywords: garnet structure, electrical conductivity, thermal expansion, thermal properties

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Authors: Osman Adiguzel

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Shape memory alloys take place in a class of smart materials by exhibiting a peculiar property called the shape memory effect. This property is characterized by the recoverability of two certain shapes of material at different temperatures. These materials are often called smart materials due to their functionality and their capacity of responding to changes in the environment. Shape memory materials are used as shape memory devices in many interdisciplinary fields such as medicine, bioengineering, metallurgy, building industry and many engineering fields. The shape memory effect is performed thermally by heating and cooling after first cooling and stressing treatments, and this behavior is called thermoelasticity. This effect is based on martensitic transformations characterized by changes in the crystal structure of the material. The shape memory effect is the result of successive thermally and stress-induced martensitic transformations. Shape memory alloys exhibit thermoelasticity and superelasticity by means of deformation in the low-temperature product phase and high-temperature parent phase region, respectively. Superelasticity is performed by stressing and releasing the material in the parent phase region. Loading and unloading paths are different in the stress-strain diagram, and the cycling loop reveals energy dissipation. The strain energy is stored after releasing, and these alloys are mainly used as deformation absorbent materials in control of civil structures subjected to seismic events, due to the absorbance of strain energy during any disaster or earthquake. Thermal-induced martensitic transformation occurs thermally on cooling, along with lattice twinning with cooperative movements of atoms by means of lattice invariant shears, and ordered parent phase structures turn into twinned martensite structures, and twinned structures turn into the detwinned structures by means of stress-induced martensitic transformation by stressing the material in the martensitic condition. Thermal induced transformation occurs with the cooperative movements of atoms in two opposite directions, <110 > -type directions on the {110} - type planes of austenite matrix which is the basal plane of martensite. Copper-based alloys exhibit this property in the metastable β-phase region, which has bcc-based structures at high-temperature parent phase field. Lattice invariant shear and twinning is not uniform in copper-based ternary alloys and gives rise to the formation of complex layered structures, depending on the stacking sequences on the close-packed planes of the ordered parent phase lattice. In the present contribution, x-ray diffraction and transmission electron microscopy (TEM) studies were carried out on two copper-based CuAlMn and CuZnAl alloys. X-ray diffraction profiles and electron diffraction patterns reveal that both alloys exhibit superlattice reflections inherited from the parent phase due to the displacive character of martensitic transformation. X-ray diffractograms taken in a long time interval show that diffraction angles and intensities of diffraction peaks change with the aging duration at room temperature. In particular, some of the successive peak pairs providing a special relation between Miller indices come close to each other. This result refers to the rearrangement of atoms in a diffusive manner.

Keywords: shape memory effect, martensitic transformation, reversibility, superelasticity, twinning, detwinning

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Authors: Sumana Kumar, Abha Misra

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Micro-supercapacitors hold great attention as one of the promising energy storage devices satisfying the increasing quest for miniaturized and portable devices. Despite having impressive power density, superior cyclic lifetime, and high charge-discharge rates, micro-supercapacitors still suffer from low energy density, which limits their practical application. The energy density (E=1/2CV²) can be increased either by increasing specific capacitance (C) or voltage range (V). Asymmetric micro-supercapacitors have attracted great attention by using two different electrode materials to expand the voltage window and thus increase the energy density. Currently, versatile fabrication technologies such as inkjet printing, lithography, laser scribing, etc., are used to directly or indirectly pattern the electrode material; these techniques still suffer from scalable production and cost inefficiency. Here, we demonstrate the scalable production of a three-dimensional (3D) carbon foam (CF) based asymmetric micro-supercapacitor by spray printing technique on an array of interdigital electrodes. The solid-state asymmetric micro-supercapacitor comprised of CF-MnO positive electrode and CF-Fe₂O₃ negative electrode achieves a high areal capacitance of 18.4 mF/cm² (2326.8 mF/cm³) at 5 mV/s and a wider potential window of 1.4 V. Consequently, a superior energy density of 5 µWh/cm² is obtained, and high cyclic stability is confirmed with retention of the initial capacitance by 86.1% after 10000 electrochemical cycles. The optimized decoration of pseudocapacitive metal oxides in the 3D carbon network helps in high electrochemical utilization of materials where the 3D interconnected network of carbon provides overall electrical conductivity and structural integrity. The research provides a simple and scalable spray printing method to fabricate an asymmetric micro-supercapacitor using a custom-made mask that can be integrated on a large scale.

Keywords: asymmetric micro-supercapacitors, high energy-density, hybrid materials, three-dimensional carbon-foam

Procedia PDF Downloads 109

Authors: Mehrnaz Mostafavi

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Lung cancer is one of the most harmful forms of cancer. The long-term survival rate of lung cancer patients treated by conventional modalities such as surgical resection, radiation, and chemotherapy remains far from satisfactory. Systemic drug delivery is rarely successful because only a limited amount of the chemotherapeutic drug targets lung tumor sites, even when administered at a high dose. Targeted delivery of drug molecules to organs or special sites is one of the most challenging research areas in pharmaceutical sciences. By developing colloidal delivery systems such as liposomes, micelles and nanoparticles a new frontier was opened for improving drug delivery. Nanoparticles with their special characteristics such as small particle size, large surface area and the capability of changing their surface properties have numerous advantages compared with other delivery systems. Targeted nanoparticle delivery to the lungs is an emerging area of interest.Multimodal or combination therapy represents a promising new method to fight disease. Therefore, a combination of different therapeutic strategies may be the best alternative to improve treatment outcomes for lung cancer. Photothermal therapy was proposed as a novel approach to treatment. In this work, photothermal therapy with gold nanoparticles and near infrared laser (NIR) irradiation was investigated.Four types of small (<100nm), NIR absorbing gold nanoparticles (nanospheres, nanorods) were synthesized using wet chemical methods and characterized by transmission electron microscopy, dynamic light scattering and UV-vis spectroscopy. Their synthesis and properties were evaluated, to determine their feasibility as a photothermal agent for clinical applications. In vitro cellular uptake studies of the nanoparticles into lung cancer cell lines was measured using light scattering microscopy.Small gold nanorods had good photothermal properties and the greatest cellular uptake, and were used in photothermal studies. Under 4W laser irradiation, an increase in temperature of 10°C and decrease in cell viability of up to 80% were obtained.

Keywords: photothermal, therapy, cancer, gold nanorods

Procedia PDF Downloads 241

Authors: Muhammad Adeel Arshad, Shaukat Ali Bhatti, Faiz-ul Hassan

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Manipulating microbial ecosystem in the rumen is considered as an important strategy to optimize production efficiency in ruminants. In the past, antibiotics and synthetic chemical compounds have been used for the manipulation of rumen fermentation. However, since the non-therapeutic use of antibiotics has been banned, efforts are being focused to search out safe alternative products. In tropics, crop residues and forage grazing are major dietary sources for ruminants. Poor digestibility and utilization of these feedstuffs by animals is a limiting factor to exploit the full potential of ruminants in this area. Hence, there is a need to enhance the utilization of these available feeding resources. One of the potential strategies in this regard is the use of direct-fed microbes. Bacteria and fungi are mostly used as direct-fed microbes to improve animal health and productivity. Commonly used bacterial species include lactic acid-producing and utilizing bacteria (Lactobacillus, Streptococcus, Enterococcus, Bifidobacterium, and Bacillus) and fungal species of yeast are Saccharomyces and Aspergillus. Direct-fed microbes modulate microbial balance in the gastrointestinal tract through the competitive exclusion of pathogenic species and favoring beneficial microbes. Improvement in weight gain and feed efficiency has been observed as a result of feeding direct-fed bacteria. The use of fungi as a direct-fed microbe may prevent excessive production of lactate and harmful oxygen in the rumen leading to better feed digestibility. However, the mechanistic mode of action for bacterial or fungal direct-fed microbes has not been established yet. Various reports have confirmed an increase in dry matter intake, milk yield, and milk contents in response to the administration of direct-fed microbes. However, the application of a direct-fed microbe has shown variable responses mainly attributed to dosages and strains of microbes. Nonetheless, it is concluded that the inclusion of direct-fed microbes may mediate the rumen ecosystem to manage lactic acid production and utilization in both clinical and sub-acute rumen acidosis.

Keywords: microbes, roughages, rumen, feed efficiency, production, fermentation

Procedia PDF Downloads 129

Authors: Jonghyuk Yoon, Hyoungwoon Song

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Recently, there are lots of increasing interest in a smart farming that represents application of modern Information and Communication Technologies (ICT) into agriculture since it provides a methodology to optimize production efficiencies by managing growing conditions of crops automatically. In order to obtain high performance and stability for smart greenhouse, it is important to identify the effect of various working parameters such as capacity of ventilation fan, vent opening area and etc. In the present study, a 3-dimensional CFD (Computational Fluid Dynamics) simulation for single-span greenhouse was conducted using the commercial program, Ansys CFX 18.0. The numerical simulation for single-span greenhouse was implemented to figure out the internal thermal and flow characteristics. In order to numerically model solar radiation that spread over a wide range of wavelengths, the multiband model that discretizes the spectrum into finite bands of wavelength based on Wien’s law is applied to the simulation. In addition, absorption coefficient of vinyl varied with the wavelength bands is also applied based on Beer-Lambert Law. To validate the numerical method applied herein, the numerical results of the temperature at specific monitoring points were compared with the experimental data. The average error rates (12.2~14.2%) between them was shown and numerical results of temperature distribution are in good agreement with the experimental data. The results of the present study can be useful information for the design of various greenhouses. This work was supported by Korea Institute of Planning and Evaluation for Technology in Food, Agriculture, Forestry and Fisheries (IPET) through Advanced Production Technology Development Program, funded by Ministry of Agriculture, Food and Rural Affairs (MAFRA)(315093-03).

Keywords: single-span greenhouse, CFD (computational fluid dynamics), solar radiation, multiband model, absorption coefficient

Procedia PDF Downloads 131

Authors: Arefeh Hesaraki

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The application of photovoltaic-thermal hybrids (PVT), which delivers both electricity and heat simultaneously from the same system, has become more popular during the past few years. This study addresses techno-economic and environmental impacts assessment of photovoltaic/thermal systems combined with a ground-source heat pump (GSHP) for three single-family houses located in Stockholm, Sweden. Three case studies were: (1) A renovated building built in 1936, (2) A renovated building built in 1973, and (3) A new building built-in 2013. Two simulation programs of SimaPro 9.1 and IDA Indoor Climate and Energy 4.8 (IDA ICE) were applied to analyze environmental impacts and energy usage, respectively. The cost-effectiveness of the system was evaluated using net present value (NPV), internal rate of return (IRR), and discounted payback time (DPBT) methods. In addition to cost payback time, the studied PVT system was evaluated using the energy payback time (EPBT) method. EPBT presents the time that is needed for the installed system to generate the same amount of energy which was utilized during the whole lifecycle (fabrication, installation, transportation, and end-of-life) of the system itself. Energy calculation by IDA ICE showed that a 5 m² PVT was sufficient to create a balance between the maximum heat production and the domestic hot water consumption during the summer months for all three case studies. The techno-economic analysis revealed that combining a 5 m² PVT with GSHP in the second case study possess the smallest DPBT and the highest NPV and IRR among the three case studies. It means that DPBTs (IRR) were 10.8 years (6%), 12.6 years (4%), and 13.8 years (3%) for the second, first, and the third case study, respectively. Moreover, environmental assessment of embodied energy during cradle- to- grave life cycle of the studied PVT, including fabrication, delivery of energy and raw materials, manufacture process, installation, transportation, operation phase, and end of life, revealed approximately two years of EPBT in all cases.

Keywords: life-cycle cost, life-cycle assessment, photovoltaic/thermal, IDA ICE, net present value

Procedia PDF Downloads 109

Authors: Ahmad Shukri Mohd Noor, Emma Ahmad Sirajudin, Rabiei Mamat

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Pertaining to a particular Marine interest, the process of data sampling could take years before a study can be concluded. Therefore, the need for a robust backup system for the data is invariably implicit. In recent advancement of Marine applications, more functionalities and tools are integrated to assist the work of the researchers. It is anticipated that this modality will continue as research scope widens and intensifies and at the same to follow suit with current technologies and lifestyles. The convenience to collect and share information these days also applies to the work in Marine research. Therefore, Marine system designers should be aware that high availability is a necessary attribute in Marine repository applications as well as a robust backup system for the data. In this paper, the approach to high availability is related both to hardware and software but the focus is more on software. We consider a NABTIC repository system that is primitively built on a single server and does not have replicated components. First, the system is decomposed into separate modules. The modules are placed on multiple servers to create a distributed system. Redundancy is added by placing the copies of the modules on different servers using Neighbor Caring Environment System(NCES) technique. NCER is utilizing parallel replication components mechanism. A background monitoring is established to check servers’ heartbeats to confirm their aliveness. At the same time, a critical adaptive threshold is maintained to make sure a failure is timely detected using Adaptive Fault Detection (AFD). A confirmed failure will set the recovery mode where a selection process will be done before a fail-over server is instructed. In effect, the Marine repository service is continued as the fail-over masks a recent failure. The performance of the new prototype is tested and is confirmed to be more highly available. Furthermore, the downtime is not noticeable as service is immediately restored automatically. The Marine repository system is said to have achieved fault tolerance.

Keywords: availability, fault detection, replication, fault tolerance, marine application

Procedia PDF Downloads 315

Authors: Pattanapon Kayansamruaj, Ha Thanh Dong, Nopadon Pirarat, Channarong Rodkhum

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Streptococcus iniae (SI) is a devastating pathogenic bacteria causing heavy mortality in farmed fish. The application of commercialized bacterin vaccine has been reported failures as the outbreaks of the new serotype of SI were emerged in farms after vaccination and subsequently caused severe losses. In the present study, we attempted to develop effective DNA vaccines against SI infection using Nile tilapia (Oreochromis niloticus) as an animal model. Two monovalent DNA vaccines were constructed by the insertion of coding sequences of cell wall-associated virulence factors-encoding genes, comprised of eno (α-enolase) and mtsB (hydrophobic membrane protein), into cytomegalovirus expression vector (pCI-neo). In the animal trial, 30-g Nile tilapia were injected intramuscularly with 15 µg of each vaccine (mock vaccine group was injected by naked pCI-neo) and maintained for 35 days prior challenging with pathogenic SI at the dosage of 107 CFU/fish. At 13 days post-challenge, the relative percent survival of pEno, pMtsB and mock vaccine were 57%, 45% and 27%, respectively. The expression levels of immune responses-associated genes, namely, IL1β, TNF-α, TGF-β, COX2, IL-6, IL-12 and IL-13, were investigated from the spleen of experimental animal at 7 days post-vaccination (PV) and 7 days post-challenge (PC) using quantitative RT-PCR technique. Generally, at 7 days PV, the pEno vaccinated group exhibited highest level of up-regulation (1.7 to 2.9 folds) of every gene, but TGF-β, comparing to pMtsB and mock vaccine groups. However, at 7 days PC, pEno group showed significant up-regulation (1.4 to 8.5 folds) of immune-related genes as similar as mock vaccine group, while pMtsB group had lowest level of up-regulation (0.7 to 3.3 folds). Summarily, this study indicated that the pEno and pMtsB vaccines could elicit the immune responses of the fish and the magnitude of gene expression at 7 days PV was also consistent with the protection level conferred by the vaccine.

Keywords: gene expression, DNA vaccine, Nile tilapia, Streptococcus iniae

Procedia PDF Downloads 324

Authors: Albert P. Ekanem, Austin I. Obiekezie, Elizabeth X. Ntia

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Introduction: Some African plants and bile from animals have shown efficacies in the treatment and control of diseases in farmed fish. The background of the study is based on the fact the African rain forest is blessed with abundance of medicinal plants that should be investigated for their use in the treatment of diseases. The significance of the study is informed by the fact that chemical-based substances accumulates in the tissues of food fish, thereby reducing the food values of such products and moreover, the continuous use of chemotherapeutants in the aquatic environments tends to degrades the affected environment. Methodology: Plants and animal products were extracted, purified and applied under in vitro and in vivo conditions to the affected organisms. Effective plants and biles were analyzed for active biological substances responsible for the activities by both qualitative and HPLC methods. Results: Extracts of Carica papaya and Mucuna pruriens were effective in the treatment of Ichthyophthiriasis in goldfish (Carassius auratus auratus) with high host tolerance. Similarly, ectoparasitic monogeneans were effectively dislodged from the gills and skin of goldfish by the application of extracts of Piper guineense at therapeutic concentrations. Artemesia annua with known antimalarial activities in human was also effective against fish monogenean parasites of Clarias gariepinus in a concentration related manner without detriments to the host. Effective antibacterial activities against Aeromonas and Pseudomonas diseases of the African catfish (Heterobranchus longifilis) were demonstrated in some plants such as Phylanthus amarus, Allium sativum, A. annua, and Citrus lemon. Bile from some animals (fish, goat, chicken, cow, and pig) showed great antibacterial activities against some gastrointestinal bacterial pathogens of fish. Conclusions: African plants and some animal bile have shown potential promise in the treatment of diseases in fish and other aquatic animals. The use of chemical-based substances for control of diseases in the aquatic environments should be restricted.

Keywords: control, diseases, fish, natural products, treatment

Procedia PDF Downloads 517

Authors: Su-Thing Ho, Shiao-Shing Chen, Hung-Te Hsu, Saikat Sinha Ray

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Forward osmosis (FO) is an emerging technology for direct and indirect potable water reuse application. However, successful implementation of FO is still hindered by the lack of draw solution recovery with high efficiency. Membrane distillation (MD) is a thermal separation process by using hydrophobic microporous membrane that is kept in sandwich mode between warm feed stream and cold permeate stream. Typically, temperature difference is the driving force of MD which attributed by the partial vapor pressure difference across the membrane. In this study, the direct contact membrane distillation (DCMD) system was used to recover diluted draw solution of FO. Na3PO4 at pH 9 and EDTA-2Na at pH 8 were used as the feed solution for MD since it produces high water flux and minimized salt leakage in FO process. At high pH, trivalent and tetravalent ions are much easier to remain at draw solution side in FO process. The result demonstrated that PTFE with pore size of 1 μm could achieve the highest water flux (12.02 L/m2h), followed by PTFE 0.45 μm (10.05 L/m2h), PTFE 0.1 μm (7.38 L/m2h) and then PP (7.17 L/m2h) while using 0.1 M Na3PO4 draw solute. The concentration of phosphate and conductivity in the PTFE (0.45 μm) permeate were low as 1.05 mg/L and 2.89 μm/cm respectively. Although PTFE with the pore size of 1 μm could obtain the highest water flux, but the concentration of phosphate in permeate was higher than other kinds of MD membranes. This study indicated that four kinds of MD membranes performed well and PTFE with the pore size of 0.45 μm was the best among tested membranes to achieve high water flux and high rejection of phosphate (99.99%) in recovery of diluted draw solution. Besides that, the results demonstrate that it can obtain high water flux and high rejection of phosphate when operated with cross flow velocity of 0.103 m/s with Tfeed of 60 ℃ and Tdistillate of 20 ℃. In addition to that, the result shows that Na3PO4 is more suitable for recovery than EDTA-2Na. Besides that, while recovering the diluted Na3PO4, it can obtain the high purity of permeate water. The overall performance indicates that, the utilization of DCMD is a promising technology to recover the diluted draw solution for FO process.

Keywords: membrane distillation, forward osmosis, draw solution, recovery

Procedia PDF Downloads 180

Authors: Yueying Chen

Abstract:

A city can be developed through memory, and memory is one of the most important elements for urban contexts. Collective memory is a collection of personal memories that can be preserved with objects, places, and events of heritage, expressing culture through spatial changes. These preserved forms can evoke a sense of community and certain emotions. Collective memory in cities reflects urban spatial alterations and historical developments. It can be preserved and reflected by revitalisation projects. A major current focus in collective memory research is how to identify and preserve memory in an intangible way. The influential elements within the preservation of collective memory mainly include institutions and objects. However, current research lacks the assessment of the collective memory after alterations of urban heritage. The assessment of urban heritage lacks visualization and qualitative methods. The emergence of the application of space syntax can fill in this gap. Hengshan Mansions was a new project in 2015. The original residential area has been replaced with a comprehensive commercial area integrating boutique shopping, upscale restaurants, and creative offices. Hengshan Mansions is located in the largest historic area in Shanghai, and its development is the epitome of the traditional culture in Shanghai. Its alteration is the newest project in this area and presents the new concept of revitalisation of urban heritage. For its physical parts, modern vitality is created, and historical information is preserved at the same time. However, most of the local people are moved away, and its functions are altered a lot. The preservation of its collective memory needs to discuss furtherly. Thus, the article builds a framework to assess the collective memory of urban heritage, including spatial configuration, spatial interaction, and cultural cognition. Then, it selects Hengshan Mansions in Shanghai as a case to analyse the assessed framework. Space syntax can be applied to visualize the assessment. Based on the analysis, the article will explore the influential reasons for the collective memory after alterations and proposes relevant advice for the preservation of the collective memory of urban heritage.

Keywords: collective memory, alternation of urban heritage, space syntax, Hengshan Mansions

Procedia PDF Downloads 127

Authors: Giancarlo La Marca, Engy Shokry, Fabio Villanelli

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Epilepsy is one of the most common neurological disorders, with an estimated prevalence of 50 million people worldwide. Twenty five percent of the epilepsy population is represented in children under the age of 15 years. For antiepileptic drugs (AED), there is a poor correlation between plasma concentration and dose especially in children. This was attributed to greater pharmacokinetic variability than adults. Hence, therapeutic drug monitoring (TDM) is recommended in controlling toxicity while drug exposure is maintained. Carbamazepine (CBZ) is a first-line AED and the drug of first choice in trigeminal neuralgia. CBZ is metabolised in the liver into carbamazepine-10,11-epoxide (CBZE), its major metabolite which is equipotent. This develops the need for an assay able to monitor the levels of both CBZ and CBZE. The aim of the present study was to develop and validate a LC-MS/MS method for simultaneous quantification of CBZ and CBZE in dried blood spots (DBS). DBS technique overcomes many logistical problems, ethical issues and technical challenges faced by classical plasma sampling. LC-MS/MS has been regarded as superior technique over immunoassays and HPLC/UV methods owing to its better specificity and sensitivity, lack of interference or matrix effects. Our method combines advantages of DBS technique and LC-MS/MS in clinical practice. The extraction process was done using methanol-water-formic acid (80:20:0.1, v/v/v). The chromatographic elution was achieved by using a linear gradient with a mobile phase consisting of acetonitrile-water-0.1% formic acid at a flow rate of 0.50 mL/min. The method was linear over the range 1-40 mg/L and 0.25-20 mg/L for CBZ and CBZE respectively. The limit of quantification was 1.00 mg/L and 0.25 mg/L for CBZ and CBZE, respectively. Intra-day and inter-day assay precisions were found to be less than 6.5% and 11.8%. An evaluation of DBS technique was performed, including effect of extraction solvent, spot homogeneity and stability in DBS. Results from a comparison with the plasma assay are also presented. The novelty of the present work lies in being the first to quantify CBZ and its metabolite from only one 3.2 mm DBS disc finger-prick sample (3.3-3.4 µl blood) by LC-MS/MS in a 10 min. chromatographic run.

Keywords: carbamazepine, carbamazepine-10, 11-epoxide, dried blood spots, LC-MS/MS, therapeutic drug monitoring

Procedia PDF Downloads 409

Authors: Adiba Matin, Daniel Cabrera, Javiera Bellolio, Jasmine Stewart, Dana Gerberi (librarian), Nathan Cummins, Fernanda Bellolio

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OBJECTIVES: Artificial intelligence (AI) tools are becoming more prevalent in healthcare settings, particularly for diagnostic and therapeutic recommendations, with an expected surge in the incoming years. The bedside use of this technology for clinicians opens the possibility of disagreements between the recommendations from AI algorithms and clinicians’ judgment. There is a paucity in the literature analyzing nature and possible outcomes of these potential conflicts, particularly related to ethical considerations. The goal of this scoping review is to identify, analyze and classify current themes and potential strategies addressing ethical conflicts originating from the conflict between AI and human recommendations. METHODS: A protocol was written prior to the initiation of the study. Relevant literature was searched by a medical librarian for the terms of artificial intelligence, healthcare and liability, ethics, or conflict. Search was run in 2021 in Ovid Cochrane Central Register of Controlled Trials, Embase, Medline, IEEE Xplore, Scopus, and Web of Science Core Collection. Articles describing the role of AI in healthcare that mentioned conflict between humans and AI were included in the primary search. Two investigators working independently and in duplicate screened titles and abstracts and reviewed full-text of potentially eligible studies. Data was abstracted into tables and reported by themes. We followed methodological guidelines for Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR). RESULTS: Of 6846 titles and abstracts, 225 full texts were selected, and 48 articles included in this review. 23 articles were included as original research and review papers. 25 were included as editorials and commentaries with similar themes. There was a lack of consensus in the included articles on who would be held liable for mistakes incurred by following AI recommendations. It appears that there is a dichotomy of the perceived ethical consequences depending on if the negative outcome is a result of a human versus AI conflict or secondary to a deviation from standard of care. Themes identified included transparency versus opacity of recommendations, data bias, liability of outcomes, regulatory framework, and the overall scope of artificial intelligence in healthcare. A relevant issue identified was the concern by clinicians of the “black box” nature of these recommendations and the ability to judge appropriateness of AI guidance. CONCLUSION AI clinical tools are being rapidly developed and adopted, and the use of this technology will create conflicts between AI algorithms and healthcare workers with various outcomes. In turn, these conflicts may have legal, and ethical considerations. There is limited consensus about the focus of ethical and liability for outcomes originated from disagreements. This scoping review identified the importance of framing the problem in terms of conflict between standard of care or not, and informed by the themes of transparency/opacity, data bias, legal liability, absent regulatory frameworks and understanding of the technology. Finally, limited recommendations to mitigate ethical conflicts between AI and humans have been identified. Further work is necessary in this field.

Keywords: ethics, artificial intelligence, emergency medicine, review

Procedia PDF Downloads 89

Authors: Sungin Jeong

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This paper presents a linear oscillating generator of cylindrical type for hybrid electric vehicle application. The focus of the study is the suggestion of the optimal model and the design rule of the cylindrical linear oscillating generator with permanent magnet in the back-iron translator. The cylindrical topology is achieved using equivalent magnetic circuit considering leakage elements as initial modeling. This topology with permanent magnet in the back-iron translator is described by number of phases and displacement of stroke. For more accurate analysis of an oscillating machine, it will be compared by moving just one-pole pitch forward and backward the thrust of single-phase system and three-phase system. Through the analysis and comparison, a single-phase system of cylindrical topology as the optimal topology is selected. Finally, the detailed design of the optimal topology takes the magnetic saturation effects into account by finite element analysis. Besides, the losses are examined to obtain more accurate results; copper loss in the conductors of machine windings, eddy-current loss of permanent magnet, and iron-loss of specific material of electrical steel. The considerations of thermal performances and mechanical robustness are essential, because they have an effect on the entire efficiency and the insulations of the machine due to the losses of the high temperature generated in each region of the generator. Besides electric machine with linear oscillating movement requires a support system that can resist dynamic forces and mechanical masses. As a result, the fatigue analysis of shaft is achieved by the kinetic equations. Also, the thermal characteristics are analyzed by the operating frequency in each region. The results of this study will give a very important design rule in the design of linear oscillating machines. It enables us to more accurate machine design and more accurate prediction of machine performances.

Keywords: equivalent magnetic circuit, finite element analysis, hybrid electric vehicle, linear oscillating generator

Procedia PDF Downloads 193

Authors: Gloria M. Ntuba-Jua, Afui M. Mih, Eneke E. T. Bechem

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Prunus africana (Hook. F.) Kalkman, commonly known as Pygeum or African cherry belongs to the Rosaceae family. It is a medium to large, evergreen tree with a spreading crown of 10 to 20 m. It is used by the traditional medical practitioners for the treatment of over 45ailments in Cameroon and sub-Sahara Africa. In modern medicine, it is used in the treatment of benign prostrate hyperplasia (BPH), prostate gland hypertrophy (enlarged prostate glands). This is possible because of its ability to produce some secondary metabolites which are believed to have bioactivity against these ailments. The ready international market for the sale of Prunus bark, uncontrolled exploitation, illegal harvesting using inappropriate techniques and poor timing of harvesting have contributed enormously to making the plant endangered. It is known to harbor a large number of endophytic fungi with the potential to produce similar secondary metabolites as the parent plant. Alternative sourcing of medicinal principles through endophytic fungi requires succinct knowledge of the endophytic fungi. This will serve as a conservation measure for Prunus africana by reducing dependence on Prunus bark for such metabolites. This work thus sought to compare the production of some major secondary metabolites produced by P. africana and some of its associated endophytic fungi. The leaves and stem bark of the plant from different provenances were soaked in methanol for 72 hrs to yield the methanolic crude extract. The phytochemical screening of the methanolic crude extracts using different standard procedures revealed the presence of tannins, flavonoids, terpenoids, saponins, phenolics and steroids. Pure cultures of some predominantly isolated endophyte species from the difference Prunus provenances such as Curvularia sp, and Morphospecies P001 were also grown in Potato Dextrose Broth (PDB) for 21 days and later extracted with Methylene dichloride (MDC) solvent after 24hrs to produce crude culture extracts. Qualitative assessment of crude culture extracts showed the presence of tannins, terpenoids, phenolics and steroids particularly β-Sitosterol, (a major bioactive metabolite) as did the plant tissues. Qualitative analysis by thin layer chromatography (TLC) was done to confirm and compare the production of β-Sitosterol (as marker compounds) in the crude extracts of the plant and endophyte. Samples were loaded on TLC silica gel aluminium barked plate (Kieselgel 60 F254, 0.2 mm, Merck) using acetone/hexane, (3.0:7.0) solvent system. They were visualized under an ultra violet lamp (UV254 and UV360). TLC revealed that leaves had a higher concentration of β-sitosterol in terms of band intensity than stem barks from the different provenances. The intensity of β-sitosterol bands in the culture extracts of endophytes was comparable to the plant extracts except for Curvularia sp (very minute) whose band was very faint. The ability of these fungi to make β-sitosterol was confirmed by TLC analysis with the compound having chromatographic properties (retention factor) similar to those of β-sitosterol standard. The ability of these major endophytes to produce secondary metabolites similar to the host has therefore been demonstrated. There is, therefore, the potential of developing the in vitro production system of Prunus secondary metabolites thereby enhancing its conservation.

Keywords: Caneroon, endophytic fungi, Prunus africana, secondary metabolite

Procedia PDF Downloads 223

Authors: Chien-Song Chyang

Abstract:

For a fluidized-bed combustion system, excess air ratio (EAR) and superficial velocity are major operating parameters affecting combustion behaviors, and these 2 factors are dependent variables since both fluidizing gas and combustion-supporting agent are air. EAR will change when superficial velocity alters, so that the effect of superficial velocity and/or EAR on combustion behaviors cannot be examined under a specific condition. When stage combustion is executed, one can discuss the effect of EAR under a certain specific superficial velocity, but the flow rate of secondary air and EAR are dependent. In order to investigate the effect of excess air ratio on the combustion behavior of a fluidized combustion system, the flue gas recirculation was adapted by the author in 2007. We can maintain a fixed flow rate of primary gas or secondary gas and change excess oxygen as an independent variable by adjusting the recirculated flue gas appropriately. In another word, we can investigate the effect of excess oxygen on the combustion behavior at a certain primary gas flow, or at a certain hydrodynamics conditions. This technique can be used at a lower turndown ratio to maintain the residual oxygen in the flue gas at a certain value. All the experiments were conducted in a pilot scale fluidized bed combustor. The fluidized bed combustor can be divided into four parts, i.e., windbox, distributor, combustion chamber, and freeboard. The combustion chamber with a cross-section of 0.8 m × 0.4 m was constructed of 6 mm carbon steel lined with 150 mm refractory to reduce heat loss. Above the combustion chamber, the freeboard is 0.64 m in inner diameter. A total of 27 tuyeres with orifices of 5 and 3 mm inside diameters mounted on a 6 mm stainless-steel plate were used as the gas distributor with an open-area-ratio of 0.52%. The Primary gas and secondary gas were fixed at 3 Nm3/min and 1 Nm3/min respectively. The bed temperature was controlled by three heat transfer tubes inserted into the bubbling bed zone. The experimental data shows that bed temperature, CO and NO emissions increase with the stoichiometric oxygen of the primary gas. NO emissions decrease with the stoichiometric oxygen of the primary. Compared with part of primary air substituted with nitrogen, a lower NO emission can be obtained while flue gas recirculation applies as part of primary air.

Keywords: fluidized bed combustion, flue gas circulation, NO emission, recycle

Procedia PDF Downloads 178