Search results for: population transfer

Authors: Abdullahi Musa, Yakubu Kukure Enebe Ibrahim, Adeshina Gujumbola

Abstract:

The emergence of multidrug resistance in clinical Escherichia coli has been associated with plasmid-mediated genes. DNA transfer among bacteria is critical to the dissemination of resistance. Plasmids have proved to be the ideal vehicles for dissemination of resistance genes. Plasmids coding for antibiotic resistance were long being recognized by many researchers globally. The study aimed at determining the antibiotic susceptibility pattern of ESBL E. coli isolates claimed to be multidrug resistance using disc diffusion method. Antibacterial activity of the test isolates was carried out using disk diffusion methods. The results showed that, majority of the multidrug resistance among clinical isolates of ESBL E. coli was as a result of acquisition of plasmid carrying antibiotic-resistance genes. Production of these ESBL enzymes by these organisms which are normally carried by plasmid and transfer from one bacterium to another has greatly contributed to the rapid spread of antibiotic resistance amongst E. coli isolates, which lead to high economic burden, increase morbidity and mortality rate, complication in therapy and limit treatment options. To curtail these problems, it is of significance to checkmate the rate at which over the counter drugs are sold and antibiotic misused in animal feeds. This will play a very important role in minimizing the spread of resistance bacterial strains in our environment.

Keywords: Escherichia coli, plasmid, multidrug resistance, ESBL, pan drug resistance

Procedia PDF Downloads 45

Authors: Yuan-Ching Chiang, Chien-Yeh Hsu, Chen Chih-Hao, Sih-Li Chen

Abstract:

The p-n junction temperature of LEDs directly influences their operating life and luminous efficiency. An excessively high p-n junction temperature minimizes the output flux of LEDs, decreasing their brightness and influencing the photon wavelength; consequently, the operating life of LEDs decreases and their luminous output changes. The maximum limit of the p-n junction temperature of LEDs is approximately 120 °C. The purpose of this research was to devise an approach for dissipating heat generated in a confined space when LEDs operate at low temperatures to reduce light decay. The cooling mode of existing commercial LED lights can be divided into natural- and forced convection cooling. In natural convection cooling, the volume of LED encapsulants must be increased by adding more fins to increase the cooling area. However, this causes difficulties in achieving efficient LED lighting at high power. Compared with forced convection cooling, heat transfer through water convection is associated with a higher heat transfer coefficient per unit area; therefore, we dissipated heat by using a closed loop water cooling system. Nevertheless, cooling water exposed to air can be easily influenced by environmental factors. Thus, we incorporated a ground heat exchanger into the water cooling system to minimize the influence of air on cooling water and then observed the relationship between the amounts of heat dissipated through the ground and LED efficiency.

Keywords: helical ground heat exchanger, high power LED, ground source cooling system, heat dissipation

Procedia PDF Downloads 564

Authors: Hamad Almohamadi, Nabeel Alharthi, Majed Alamoudi

Abstract:

Biphasic electrodes featuring CuSx/NiSx electrodeposited on nickel foam have been investigated for their electrocatalytic activity in water splitting. The study investigates the impacts of an S-vacancy induced biphasic design on the overpotential and Tafel slope. According to the findings, the NiSx/CuSx/NF electrode with S-vacancy defects displays stronger oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) activity with lower overpotential and a steeper Tafel slope than the non-defect sample. NiSx/CuSx/NF exhibits the lowest overpotential value of 212 mV vs reversible hydrogen electrode (RHE) for OER and −109 mV vs RHE for HER at 10 mA cm−2. Tafel slope of 25.4 mV dec−1 for OER and −108 mV dec−1 for OER found of that electrode. The electrochemical surface area (ECSA) and diffusion impedance of the electrode is calculated. The maximum ECSA, lowest series resistance and lowest charge transfer resistance are found in the *NiSx/CuSx/NF sample with S-vacancy defects, showing increased electrical conductivity and quick charge transfer kinetics. The *NiSx/CuSx/NF electrode was found to be stable for 80 hours in pure water splitting and 20 hours in sea-water splitting. The investigation comes to the conclusion that the enhanced water splitting activity and electrical conductivity of the electrode are caused by S-vacancy defects resulting in improved water splitting performance.

Keywords: water splitting, electrocatalyst, biphasic design, electrodeposition

Procedia PDF Downloads 51

Authors: Brianna Z. Ross, Jonathan N. Livingston

Abstract:

Given that discussions of racism and racial tensions have become more salient, there is a need to evaluate the impacts of racialization among Black individuals. Racial discrimination has become one of the most common experiences within the Black American population. Likewise, Black individuals have indicated a need to address their racial identities at an earlier age than their non-Black peers. Further, Black individuals have been found at the forefront of multiple social and political movements, including but not limited to the Civil Rights Movement, Black Lives Matter, MeToo, and Say Her Name. Moreover, the present study sought to explore the predictive relationships that exist between racial discrimination, racial identity, and activism in the Black community. The results of standard and hierarchical regression analyses revealed that racial discrimination and racial identity significantly predict each other, but only racial discrimination is a significant predictor for the relationship to activism. Nonetheless, the results from this study will provide a basis for social scientists to better understand the impacts of racialization on the Black American population.

Keywords: activism, racialization, racial discrimination, racial identity

Procedia PDF Downloads 131

Authors: Fredrick O. Okumu, Mangaka C. Matoetoe

Abstract:

Silver-platinum (Ag-Pt) bimetallic nanoparticles (NPs) with varying mole fractions (1:1, 1:3 and 3:1) were prepared by co-reduction of hexachloroplatinate and silver nitrate with sodium citrate. Upon successful formation of both monometallic and bimetallic (BM) core shell nanoparticles, cyclic voltammetry (CV) was used to characterize the NPs. The drop coated nanofilms on the GC substrate showed characteristic peaks of monometallic Ag NPs; Ag+/Ag0 redox couple as well as the Pt NPs; hydrogen adsorption and desorption peaks. These characteristic peaks were confirmed in the bimetallic NPs voltammograms. The following varying current trends were observed in the BM NPs ratios; GCE/Ag-Pt 1:3 > GCE/Ag-Pt 3:1 > GCE/Ag-Pt 1:1. Fundamental electrochemical properties which directly or indirectly affects the applicability of films such as; diffusion coefficient (D), electroactive surface coverage, electrochemical band gap, electron transfer coefficient (α) and charge (Q) were assessed using Randles - Sevcik plot and Laviron’s equations . High charge and surface coverage was observed in GCE/Ag-Pt 1:3 which supports its enhanced current. GCE/Ag-Pt 3:1 showed high diffusion coefficient while GCE/Ag-Pt 1:1 possessed high electron transfer coefficient that is facilitated by its high apparent heterogeneous rate constant relative to other BM NPs ratios. Surface redox reaction was determined as adsorption controlled in all modified GCEs. Surface coverage is inversely proportional to size; therefore the surface coverage data suggests that Ag-Pt 1:1 NPs have a small particle size. Generally, GCE/Ag-Pt 1:3 depicts the best electrochemical properties.

Keywords: characterization, core-shell, electrochemical, nanoparticles

Procedia PDF Downloads 255

Authors: Jiawei Li

Abstract:

How cooperation emerges and persists in a population of selfish agents is a fundamental question in evolutionary game theory. Our research shows that Collective Strategies with Master-Slave Mechanism (CSMSM) defeat Tit-for-Tat and other well-known strategies in spatial iterated prisoner’s dilemma. A CSMSM identifies kin members by means of a handshaking mechanism. If the opponent is identified as non-kin, a CSMSM will always defect. Once two CSMSMs meet, they play master and slave roles. A mater defects and a slave cooperates in order to maximize the master’s payoff. CSMSM outperforms non-collective strategies in spatial IPD even if there is only a small cluster of CSMSMs in the population. The existence and performance of CSMSM in spatial iterated prisoner’s dilemma suggests that cooperation first appears and persists in a group of collective agents.

Keywords: Evolutionary game theory, spatial prisoners dilemma, collective strategy, master-slave mechanism

Procedia PDF Downloads 135

Authors: K. Zhumadilov, P. Kazymbet, A. Ivannikov, M. Bakhtin, A. Akylbekov, K. Kadyrzhanov, A. Morzabayev, M. Hoshi

Abstract:

The aim of the study is to evaluate the possible excess of dose received by uranium processing plant workers. The possible excess of dose of workers was evaluated with comparison with population pool (Stepnogorsk) and control pool (Astana city). The measured teeth samples were extracted according to medical indications. In total, twenty-seven tooth enamel samples were analyzed from the residents of Stepnogorsk city (180 km from Astana city, Kazakhstan). About 6 tooth samples were collected from the workers of uranium processing plant. The results of tooth enamel dose estimation show us small influence of working conditions to workers, the maximum excess dose is less than 100 mGy. This is pilot study of EPR dose estimation and for a final conclusion additional sample is required.

Keywords: EPR dose, workers, uranium mines, tooth samples

Procedia PDF Downloads 393

Authors: A. Benaiche

Abstract:

In the current situation, the automobile has become the main means of locomotion. It allows traveling long distances, encouraging urban sprawl. To counteract this trend, the train is often proposed as an alternative to the car. Simultaneously, the favoring of urban development around public transport nodes such as railway stations is one of the main issues of the coordination between urban planning and transportation and the keystone of the sustainable urban development implementation. In this context, this paper focuses on the study of the spatial structuring dynamics around the railway. Specifically, it is a question of studying the demographic dynamics in rail corridors of Nantes, Angers and Le Mans (Western France) basing on the radiation of railway stations. Consequently, the methodology is concentrated on the knowledge of demographic weight and gains of these corridors, the index of urban intensity and the mobility behaviors (workers’ travels, scholars' travels, modal practices of travels). The perimeter considered to define the rail corridors includes the communes of urban area which have a railway station and communes with an access time to the railway station is less than fifteen minutes by car (time specified by the Regional Transport Scheme of Travelers). The main tools used are the statistical data from the census of population, the basis of detailed tables and databases on mobility flows. The study reveals that the population is not tightened along rail corridors and train use is minimal despite the presence of a nearby railway station. These results lead to propose guidelines to make the train, a real vector of mobility across the rail corridors.

Keywords: coordination between urban planning and transportation, rail corridors, railway stations, travels

Procedia PDF Downloads 233

Authors: Cláudia Alcoforado, Anabela Ribeiro

Abstract:

This paper is part of an ongoing PhD thesis. It seeks to develop a model to identify the spatial failures of the public transportation supply. In the construction of the model, it also seeks to detect the social needs arising from the disadvantage in transport. The case study is carried out for the Brazilian city of Recife. Currently, Recife has a population density of 7,039.64 inhabitants per km². Unfortunately, only 46.9% of urban households on public roads have adequate urbanization. Allied to this reality, the trend of the occupation of the poorest population is that of the peripheries, a fact that has been consolidated in Brazil and Latin America, thus burdening the families' income, since the greater the distances covered for the basic activities and consequently also the transport costs. In this way, there have been great impacts caused by the supply of public transportation to locations with low demand or lack of urban infrastructure. The model under construction uses methods such as Currie’s Gap Assessment associated with the London’s Public Transport Access Level, and the Public Transport Accessibility Index developed by Saghapour. It is intended to present the stage of the thesis with the spatial/need gaps of the neighborhoods of Recife already detected. The benefits of the geographic information system are used in this paper. It should be noted that gaps are determined from the transport supply indices. In this case, considering the presence of walking catchment areas. Still in relation to the detection of gaps, the relevant demand index is also determined. This, in turn, is calculated through indicators that reflect social needs. With the use of the smaller Brazilian geographical unit, the census sector, the model with the inclusion of population density in the study areas should present more consolidated results. Based on the results achieved, an analysis of transportation disadvantage will be carried out as a factor of social exclusion in the study area. It is anticipated that the results obtained up to the present moment, already indicate a strong trend of public transportation in areas of higher income classes, leading to the understanding that the most disadvantaged population migrates to those neighborhoods in search of employment.

Keywords: gap assessment, public transport supply, social exclusion, spatial gaps

Procedia PDF Downloads 167

Authors: Sofia N. Gonçalves, Duarte M. S. Albuquerque, José C. F. Pereira

Abstract:

Microwave technology has been gaining importance in contributing to decarbonization processes in high energy demand industries. Despite the several numerical models presented in the literature, a proper Verification and Validation exercise is still lacking. This is important and required to evaluate the physical process model accuracy and adequacy. Another issue addresses impedance matching, which is an important mechanism used in microwave experiments to increase electromagnetic efficiency. Such mechanism is not available in current computational tools, thus requiring an external numerical procedure. A numerical model was implemented to study the continuous processing of limestone with microwave heating. This process requires the material to be heated until a certain temperature that will prompt a highly endothermic reaction. Both a 2D and 3D model were built in COMSOL Multiphysics to solve the two-way coupling between Maxwell and Energy equations, along with the coupling between both heat transfer phenomena and limestone endothermic reaction. The 2D model was used to study and evaluate the required numerical procedure, being also a benchmark test, allowing other authors to implement impedance matching procedures. To achieve this goal, a controller built in MATLAB was used to continuously matching the cavity impedance and predicting the required energy for the system, thus successfully avoiding energy inefficiencies. The 3D model reproduces realistic results and therefore supports the main conclusions of this work. Limestone was modeled as a continuous flow under the transport of concentrated species, whose material and kinetics properties were taken from literature. Verification and Validation of the coupled model was taken separately from the chemical kinetic model. The chemical kinetic model was found to correctly describe the chosen kinetic equation by comparing numerical results with experimental data. A solution verification was made for the electromagnetic interface, where second order and fourth order accurate schemes were found for linear and quadratic elements, respectively, with numerical uncertainty lower than 0.03%. Regarding the coupled model, it was demonstrated that the numerical error would diverge for the heat transfer interface with the mapped mesh. Results showed numerical stability for the triangular mesh, and the numerical uncertainty was less than 0.1%. This study evaluated limestone velocity, heat transfer, and load influence on thermal decomposition and overall process efficiency. The velocity and heat transfer coefficient were studied with the 2D model, while different loads of material were studied with the 3D model. Both models demonstrated to be highly unstable when solving non-linear temperature distributions. High velocity flows exhibited propensity to thermal runways, and the thermal efficiency showed the tendency to stabilize for the higher velocities and higher filling ratio. Microwave efficiency denoted an optimal velocity for each heat transfer coefficient, pointing out that electromagnetic efficiency is a consequence of energy distribution uniformity. The 3D results indicated the inefficient development of the electric field for low filling ratios. Thermal efficiencies higher than 90% were found for the higher loads and microwave efficiencies up to 75% were accomplished. The 80% fill ratio was demonstrated to be the optimal load with an associated global efficiency of 70%.

Keywords: multiphysics modeling, microwave heating, verification and validation, endothermic reactions modeling, impedance matching, limestone continuous processing

Procedia PDF Downloads 128

Authors: R. Morbidelli, C. Saltalippi, A. Flammini, J. Dari

Abstract:

This work analyses what effect systematic awareness-raising of the population on domestic water consumption produces. In a period where the availability of water is continually decreasing due to reduced rainfall, it is of paramount importance to raise awareness among the population. We conducted an experiment on a large sample of homes in urban areas of Central Italy. In a first phase, lasting three weeks, normal per capita water consumption was quantified. Subsequently, instructions were given on how to save water during various uses in the household (showers, cleaning hands, use of water in toilets, watering small green areas, use of water in the kitchen, ...), and small visual messages were posted at water dispensers to remind users to behave properly. Finally, household consumption was assessed again for a further 3 weeks. This experiment made it possible to quantify the effect of the awareness-raising action on the reduction of water consumption without the use of any structural action (replacement of dispensers, improvement of the water system, ...).

Keywords: water saving, urban areas, awareness-raising, climate change

Procedia PDF Downloads 28

Authors: Rasime Kalkan, Emine Ikbal Atli, Ali Arslantaş, Muhsin Özdemir, Sevilhan Artan

Abstract:

Glioblastoma (WHO grade IV), is the malignant form of brain tumor, the genetic background of the GBM is highly variable. The tumor mass of a GBM is multilayered and every tumor layer shows distinct characteristics with a different cell population. The treatment planning of GBM should be focused on the tumor genetic characteristics. We screened primary glioblastoma multiforme (GBM) in a population-based study for MGMT and RARβ methylation and IDH1 mutation correlated them with clinical data and treatment. There was no correlation between MGMT-promoter methylation and overall survival. The overall survival time of the patients with methylated RARβ was statically (OS;p<0,05) significance between the patients who were treated with chemotherapy and radiotherapy. Here we showed the status of IDH1 gene associatied with younger age. We demonstrated that the together with MGMT gene the RARβ gene should be used as a potantial treatment decision marker for GBMs.

Keywords: RARβ, primary glioblastoma multiforme, methylation, MGMT

Procedia PDF Downloads 327

Authors: S. R. Dehghani, G. F. Naterer, Y. S. Muzychka

Abstract:

Wave-impact sea spray creates many droplets which form a spray cloud traveling over marine objects same as marine vessels and offshore structures. In cold climates such as Arctic reigns, sea spray icing, which is ice accretion on cold substrates, is strongly dependent on the wave-impact sea spray. The rate of cooling of droplets affects the process of icing that can yield to dry or wet ice accretion. Trajectories of droplets determine the potential places for ice accretion. Combining two models of trajectories and heat transfer for droplets can predict the risk of ice accretion reasonably. The majority of the cooling of droplets is because of droplet evaporations. In this study, a combined model using trajectory and heat transfer evaluate the situation of a cloud of spray from the generation to impingement. The model uses some known geometry and initial information from the previous case studies. The 3D model is solved numerically using a standard numerical scheme. Droplets are generated in various size ranges from 7 mm to 0.07 mm which is a suggested range for sea spray icing. The initial temperature of droplets is considered to be the sea water temperature. Wind velocities are assumed same as that of the field observations. Evaluations are conducted using some important heading angles and wind velocities. The characteristic of size-velocity dependence is used to establish a relation between initial sizes and velocities of droplets. Time intervals are chosen properly to maintain a stable and fast numerical solution. A statistical process is conducted to evaluate the probability of expected occurrences. The medium size droplets can reach the highest heights. Very small and very large droplets are limited to lower heights. Results show that higher initial velocities create the most expanded cloud of spray. Wind velocities affect the extent of the spray cloud. The rate of droplet cooling at the start of spray formation is higher than the rest of the process. This is because of higher relative velocities and also higher temperature differences. The amount of water delivery and overall temperature for some sample surfaces over a marine vessel are calculated. Comparing results and some field observations show that the model works accurately. This model is suggested as a primary model for ice accretion on marine vessels.

Keywords: evaporation, sea spray, marine icing, numerical solution, trajectory

Procedia PDF Downloads 210

Authors: Carlos M. Goncalves, Luisa Duarte, Teresa Cartaxo

Abstract:

The aim of this work was to understand the reasons behind the underutilization of electroconvulsive therapy (ECT) in the younger population and raise possible solutions. We conducted a non-systematic review of literature throughout a search on PubMed, using the terms ‘children’, ‘adolescents’ and ‘electroconvulsive’, ‘therapy’. Candidate articles written in languages other than English were excluded. Articles were selected according to title and/or abstract’s content relevance, resulting in a total of 5 articles. ECT is a recognized effective treatment in adults for several psychiatric conditions. As in adults, ECT in children and adolescents is proven most beneficial in the treatment of severe mood disorders, catatonia, and, to a lesser extent, schizophrenia. ECT in adults has also been used to treat autism’s self-injurious behaviours, Tourette’s syndrome and resistant first-episode schizophrenia disorder. Despite growing evidence on its safety and effectiveness in children and adolescents, like those found in adults, ECT remains a controversial and underused treatment in patients this age, even when it is clearly indicated. There are various possible reasons to this; limited awareness among professionals (lack of knowledge and experience among child psychiatrists), stigmatic public opinion (despite positive feedback from patients and families, there is an unfavourable and inaccurate representation in the media, contributing to a negative public opinion), legal restrictions and ethical controversies (restrictive regulations such as a minimum age for administration), lack of randomized trials (the currently available studies are retrospective, with small size samples, and most of the publications are either case reports or case series). This shows the need to raise awareness and knowledge, not only for mental health professionals, but also to the general population, through the media, regarding indications, methods and safety of ECT in order to provide reliable information to the patient and families. Large-scale longitudinal studies are also useful to further demonstrate the efficacy and safety of ECT and can aid in the formulation of algorithms and guidelines as without these changes, the availability of ECT to the younger population will remain restricted by regulations and social stigma. In conclusion, these results highlight that lack of adequate knowledge and accurate information are the most important factors behind the underutilization of ECT in younger population. Mental healthcare professionals occupy a cornerstone position; if data is given by a well-informed healthcare professional instead of the media, general population (including patients and their families) will probably regard the procedure in a more favourable way. So, the starting point should be to improve health care professional’s knowledge and experience on this choice of treatment.

Keywords: adolescents, children, electroconvulsive, therapy

Procedia PDF Downloads 111

Authors: Paras Ram, Vikas Kumar

Abstract:

The transmission of Malaria with seasonal were studied through the use of mathematical models. The data from the annual number of Malaria cases reported to the Division of Epidemiology, Ministry of Public Health, Thailand during the period 1997-2011 were analyzed. The transmission of Malaria with seasonal was studied by formulating a mathematical model which had been modified to describe different situations encountered in the transmission of Malaria. In our model, the population was separated into two groups: the human and vector groups, and then constructed a system of nonlinear differential equations. Each human group was divided into susceptible, infectious in hot season, infectious in rainy season, infectious in cool season and recovered classes. The vector population was separated into two classes only: susceptible and infectious vectors. The analysis of the models was given by the standard dynamical modeling.

Keywords: ferrofluid, magnetic field, porous medium, rotating disk, Neuringer-Rosensweig Model

Procedia PDF Downloads 409

Authors: Folayele Oluyemi Akindeju, Tobi Joseph Ajoro

Abstract:

The city as a complex system exhibiting chaotic behaviour is in a state of constant change, in response to prevailing social, economic, environmental and technological factors. Without adequate investigation and control mechanisms to tame the sporadic nature of growth in most urban areas of cities in developing regions, organic sprawling visibly manifests with its attendant problems, most especially at peri-urban areas. The Lagos Megacity region in southwest Nigeria, as one of the largest megacities in the world contends with the challenges of sprawling at the peri-urban areas especially along emerging transit corridors. Due to the seemingly unpredictable nature of this growth, this paper attempts a morphological investigation into the growth of peri-urban settlements along the Mowe-Ibafo transit corridor of the Megacity region over a temporal space of three decades (1984-2014). This study adopts the application of the Fractal Analysis and Regression Analysis methods through the correlation of population density and fractal dimension values to establish the pattern and nature of growth, due to the inadequacies of conventional methods of urban analysis which cannot deal with the unpredictability of such complex urban forms as the peri-urban areas. It was deduced that the dynamic urban expansion in the last three decades resulted in about 74.2% urban change rate between 1984 and 2000 and 63.4% urban change rate between 2000 and 2014. With the R2 value between the fractal dimension and population density been 1, the regression model indicates a positive correlation between Fractal Dimension (D) and Population Density (pop/km2), where the increase in the population density from 5740 pop/km2 to 8060 pop/km2 and later decrease to 7580 pop/km2 leads to an increase in the fractal dimension of urban growth from 1.451 in 1984 to 1.853 in 2014. This, therefore, justifies the ability to predict and determine the nature and direction of growth of complex entities and is sufficient to substantially suggest the need for adequate policy framework towards sustainable urban planning and infrastructural provision in the Peri-urban areas.

Keywords: fractal analysis, Lagos Megacity, peri-urban, sprawling, urban morphology

Procedia PDF Downloads 161

Authors: Sanjeeb Sutradhar, Archita Patnaik

Abstract:

Histidine is one of the twenty-two naturally occurring essential amino acids exhibiting two conformations, L-histidine and D-histidine. D-Histidine is biologically inert, while L-histidine is bioactive because of its conversion to neurotransmitter or neuromodulator histamine in both brain as well as central nervous system. The deficiency of L-histidine causes serious diseases like Parkinson’s disease, epilepsy and the failure of normal erythropoiesis development. Gold nanocomposites are attractive materials due to their excellent biocompatibility and are easy to adsorb on the electrode surface. In the present investigation, hydrophobic fullerene-C60 was functionalized with homocysteine via nucleophilic addition reaction to make it hydrophilic and to successively make the nanocomposite with in-situ prepared gold nanoparticles with ascorbic acid as reducing agent. The electronic structure calculations of the AuNPs@Hcys-C60 nanocomposite showed a drastic reduction of HOMO-LUMO gap compared to the corresponding molecules of interest, indicating enhanced electron transportability to the electrode surface. In addition, the electrostatic potential map of the nanocomposite showed the charge was distributed over either end of the nanocomposite, evidencing faster direct electron transfer from nanocomposite to the electrode surface. This nanocomposite showed catalytic activity; the nanocomposite modified glassy carbon electrode showed a tenfold higher kₑt, the electron transfer rate constant than the bare glassy carbon electrode. Significant improvement in its sensing behavior by square wave voltammetry was noted.

Keywords: fullerene-C60, gold nanocomposites, L-Histidine, square wave voltammetry

Procedia PDF Downloads 236

Authors: Yasser Mahmoudi, Nader Karimi

Abstract:

The present work examines analytically the effect internal heat generation on temperature fields in a channel partially-filled with a porous under local thermal non-equilibrium condition. The Darcy-Brinkman model is used to represent the fluid transport through the porous material. Two fundamental models (models A and B) represent the thermal boundary conditions at the interface between the porous medium and the clear region. The governing equations of the problem are manipulated, and for each interface model, exact solutions for the solid and fluid temperature fields are developed. These solutions incorporate the porous material thickness, Biot number, fluid to solid thermal conductivity ratio Darcy number, as the non-dimensional energy terms in fluid and solid as parameters. Results show that considering any of the two models and under zero or negative heat generation (heat sink) and for any Darcy number, an increase in the porous thickness increases the amount of heat flux transferred to the porous region. The obtained results are applicable to the analysis of complex porous media incorporating internal heat generation, such as heat transfer enhancement (THE), tumor ablation in biological tissues and porous radiant burners (PRBs).

Keywords: porous media, local thermal non-equilibrium, forced convection, heat transfer, exact solution, internal heat generation

Procedia PDF Downloads 444

Authors: Rugang Tian

Abstract:

In this study, we generated whole-genome sequence (WGS) data from110 native cattle. Together with whole-genome sequences from world-wide cattle populations, we estimated the genetic diversity and population genetic structure of different cattle populations. Our findings revealed clustering of cattle groups in line with their geographic locations. We identified noticeable genetic diversity between indigenous cattle breeds and commercial populations. Among all studied cattle groups, lower genetic diversity measures were found in commercial populations, however, high genetic diversity were detected in some local cattle, particularly in Rashoki and Mongolian breeds. Our search for potential genomic regions under selection in native cattle revealed several candidate genes related with immune response and cold shock protein on multiple chromosomes such as TRPM8, NMUR1, PRKAA2, SMTNL2 and OXR1 that are involved in energy metabolism and metabolic homeostasis.

Keywords: cattle, whole-genome, population structure, adaptation

Procedia PDF Downloads 46

Authors: Carrie Prendergast, Lisa Bortman

Abstract:

The focus of this presentation will be on non-traditional (adult) students as they seek their Bachelors’ degrees online. This presentation will specifically examine nontraditional online student perceptions of Tinto’s success conditions: expectations, support, assessment, and engagement. Expectations include those of the student, the faculty and the institution. Support includes academic, social, and financial support. Feedback and assessment encompasses feedback in the classroom, upon entry, and on an institutional level. The fourth success condition is involvement or engagement of students with their peers and faculty in both academic and social contexts. This program will review and discuss a rich, detailed description of the lived experience of the nontraditional online student to add to the paucity of research on this understudied population and guide higher education professionals in supporting this growing population of students.

Keywords: adult students, online education, student success, vincent tinto

Procedia PDF Downloads 352

Authors: R. Morbidelli, C. Saltalippi, A. Flammini, J. Dari

Abstract:

This work analyses what effect systematic awareness-raising of the population on domestic water consumption produces. In a period where the availability of water is continually decreasing due to reduced rainfall, it is of paramount importance to raise awareness among the population. We conducted an experiment on a large sample of homes in urban areas of Central Italy. In the first phase, lasting three weeks, normal per capita, water consumption was quantified. Subsequently, instructions were given on how to save water during various uses in the household (showers, cleaning hands, use of water in toilets, watering small green areas, use of water in the kitchen, ...), and small visual messages were posted at water dispensers to remind users to behave properly. Finally, household consumption was assessed again for a further three weeks. This experiment made it possible to quantify the effect of the awareness-raising action on the reduction of water consumption without the use of any structural action (replacement of dispensers, improvement of the water system, ...).

Keywords: water saving, urban areas, awareness-raising, climate change

Procedia PDF Downloads 91

Authors: Suresh Sahu, Abhijeet M. Vaidya, Naresh K. Maheshwari

Abstract:

The efforts to understand the heat transfer behavior of supercritical water in supercritical water cooled reactor (SCWR) are ongoing worldwide to fulfill the future energy demand. The higher thermal efficiency of these reactors compared to a conventional nuclear reactor is one of the driving forces for attracting the attention of nuclear scientists. In this work, a solution procedure has been described for solving supercritical fluid flow problems in complex geometries. The solution procedure is based on non-staggered grid. All governing equations are discretized by finite volume method (FVM) in curvilinear coordinate system. Convective terms are discretized by first-order upwind scheme and central difference approximation has been used to discretize the diffusive parts. k-ε turbulence model with standard wall function has been employed. SIMPLE solution procedure has been implemented for the curvilinear coordinate system. Based on this solution method, 3-D Computational Fluid Dynamics (CFD) code has been developed. In order to demonstrate the capability of this CFD code in supercritical fluid flows, heat transfer to supercritical water in circular tubes has been considered as a test problem. Results obtained by code have been compared with experimental results reported in literature.

Keywords: curvilinear coordinate, body-fitted mesh, momentum interpolation, non-staggered grid, supercritical fluids

Procedia PDF Downloads 119

Authors: Ankitsinh Chauhan, Vimal Patel, A. D. Parekh, Ishant patil

Abstract:

This study delves into the crucial influence of cooling tower fan operation on the performance of a chiller plant, with a specific focus on the Chiller Plant at SVNIT. Continuous operation of the chiller plant led to unexpected damage to the cooling tower's belt drive, rendering the cooling tower fan non-operational. Consequently, the efficiency of heat transfer in the condenser was significantly impaired. In response, we analyzed and calculated several vital parameters, including the Coefficient of Performance (COP), heat rejection in the condenser (Qc), work required for the compressor (Wc), and heat absorbed by the refrigerant in the evaporator (Qe). Our findings revealed that in the absence of the cooling tower fan, relying solely on natural convection, the COP of the chiller plant reached a minimum value of 5.49. However, after implementing a belt drive to facilitate forced convection for the cooling tower fan, the COP of the chiller plant experienced a noteworthy improvement, reaching approximately 6.27. Additionally, the utilization of forced convection resulted in an impressive reduction of 8.9% in compressor work, signifying enhanced energy efficiency. This study underscores the critical role of cooling tower fan operation in optimizing chiller plant performance, with practical implications for energy-efficient HVAC systems. It highlights the potential benefits of employing forced convection mechanisms, such as belt drives, to ensure efficient heat transfer in the condenser, ultimately contributing to improved energy utilization and reduced operational costs in cooling.

Keywords: cooling tower, chiller Plant, cooling tower fan, energy efficiency, VCRS.

Procedia PDF Downloads 16

Authors: Kumar Gular, Viswanathan S., Mastour Saeed Alshahrani, Ravi Shankar Reddy, Jaya Shanker Tedla, Snehil Dixit, Ajay Prasad Gautam, Venkata Nagaraj Kakaraparthi, Devika Rani Sangadala

Abstract:

Background: Despite trunk control’s significant contribution to improving various functional activity components, the independent effect of trunk performance on quality of life is yet to be estimated in stroke survivors. Ascertaining the correlation between trunk control and self-reported quality of life while evaluating the effect of demographic and clinical characteristics on their relationship will guide concerned healthcare professionals in designing ideal rehabilitation protocols during the late sub-acute stroke stage of recovery. The aims of the present research were to (1) investigate the associations of trunk performance with self-rated quality of life and (2) evaluate if age, body mass index (BMI), and clinical characteristics mediate the relationship between trunk motor performance and perceived quality of life in the sub-acute stroke population. Methods: Trunk motor functions and quality of life among the late sub-acute stroke population aged 57.53 ± 6.42 years were evaluated through the trunk Impairment Scale (TIS) and Stroke specific quality of life (SSQOL) questionnaire, respectively. Pearson correlation coefficients and mediation analysis were performed to elucidate the relationship of trunk motor function with quality of life and determine the mediation impact of demographic and clinical characteristics on their association, respectively. Results: The current study observed significant correlations between trunk motor functions (TIS) and quality of life (SSQOL) with r=0.68 (p<0.001). Age, BMI, and type of stroke were detected as potential mediating factors in the association between trunk performance and quality of life. Conclusion: Validated associations between trunk motor functions and perceived quality of life among the late sub-acute stroke population emphasize the importance of comprehensive evaluation of trunk control. Rehabilitation specialists should focus on appropriate strategies to enhance trunk performance anticipating the potential effects of age, BMI, and type of stroke to improve health-related quality of life in stroke survivors.

Keywords: sub-acute stroke, quality of life, functional independence, trunk control

Procedia PDF Downloads 57

Authors: Samira Ghasempourkazemi

Abstract:

In terms of the COVID-19 pandemic, lots of mutations in the urban system, which have systemic impacts, have clearly appeared. COVID-19 not only had a direct impact on health but also caused significant losses to other departments, including the economy, education, tourism, environment and the construction industry. Therefore, the pandemic caused a disruption in the whole urban system. Particularly, today’s large urban areas are not designed in order to be compatible during a pandemic. Hence, cities are more vulnerable to infectious disease threats according to the population density, built environment and socioeconomic aspects. Considering the direct relationship between population and rate of infection, higher rates are given to those individuals located in areas with high-density populations. Population density can be a factor that seems to have a strong impact on the spread of infectious diseases. Thus, the preliminary hypothesis can be related to a densely populated areas which become hotspots for the rapid spread of the pandemic due to high levels of interaction. In addition, some other indicators can be effective in this condition, such as age range, education and socio-economy. To figure out the measure of infectious disease risk in densely populated areas in Istanbul is an objective of this study. Besides, this study intends to figure out Vulnerability Index in the case of COVID-19. In order to achieve the proper result, the considered method can be Analytic Hierarchy Process (AHP) by involving the mentioned variables. In the end, the study represents the COVID Vulnerability of densely populated areas in a metro city and the gaps that need to be identified and plugged for the pandemic-resilience city of tomorrow.

Keywords: infectious disease, COVID-19, urban system, densely populated area

Procedia PDF Downloads 65

Authors: Rajandeep Kaur, Rajeev Gupta

Abstract:

Background: Chronic myeloid leukemia (CML) is the most common leukaemia in India. The annual incidence of chronic myeloid leukemia in India was originally reported to be 0.8 to 2.2 per 1,00,000 population. CML is a clonal disorder that is usually easily diagnosed because the leukemic cells of more than 95% of patients have a distinctive cytogenetic abnormality, the Philadelphia chromosome (Ph1). The approval of tyrosine kinase inhibitors (TKIs), which target BCR-ABL1 kinase activity, has significantly reduced the mortality rate associated with chronic myeloid leukemia (CML) and revolutionized treatment. Material and Methods: 80 diagnosed cases of CML were taken. Investigations were done. Bone marrow and molecular studies were also done and with EUTOS, patients were stratified into low and high-risk groups and then treatment with Imatinib was given to all patients and the molecular response was evaluated at 6 months and 12 months follow up with BCR-ABL by RT-PCR quantitative assay. Results: In the study population, out of 80 patients in the study population, 40 were females and 40 were males, with M: F is 1:1. Out of total 80 patients’ maximum patients (54) were in 31-60 years age group. Our study showed a most common symptom of presentation is abdominal discomfort followed by fever. Out of the total 80 patients, 25 (31.3%) patients had high EUTOS scores and 55 (68.8%) patients had low EUTOS scores. On 6 months follow up 36.3% of patients had Complete Molecular Response, 16.3% of patients had Major Molecular Response and 47.5% of patients had No Molecular Response but on 12 months follow up 71.3% of patients had Complete Molecular Response, 16.25% of patients had Major Molecular Response and 12.5% patients had No Molecular Response. Conclusion: In this study, we found a significant correlation between EUTOS score and Molecular response at 6 months and 12 months follow up after Imatinib therapy.

Keywords: chronic myeloid leukemia, European treatment and outcome study score, hematological response, molecular response, tyrosine kinase inhibitor

Procedia PDF Downloads 86

Authors: Ramazan Kadiev, Arkadi Ponossov

Abstract:

Semidiscrete systems contain both continuous and discrete components. This means that the dynamics is mostly continuous, but at certain instants, it is exposed to abrupt influences. Such systems naturally appear in applications, for example, in biological and ecological models as well as in the control theory. Therefore, the study of semidiscrete systems has recently attracted the attention of many specialists. Stochastic effects are an important part of any realistic approach to modeling. For example, stochasticity arises in the population dynamics, demographic and ecological due to a change in time of factors external to the system affecting the survival of the population. In control theory, random coefficients can simulate inaccuracies in measurements. It will be shown in the presentation how to incorporate such effects into semidiscrete systems. Stability analysis is an essential part of modeling real-world problems. In the presentation, it will be explained how sufficient conditions for the moment stability of solutions in terms of the coefficients for linear semidiscrete stochastic equations can be derived using non-Lyapunov technique.

Keywords: abrupt changes, exponential stability, regularization, stochastic noises

Procedia PDF Downloads 173

Authors: Priyansha Sharma, Sibani Mund, Sivakumar Vaidyanathan

Abstract:

Solid-state synthesis methods were used for the synthesis of pure red emissive Li¬3BaSrxCa(1-x)Eu2.7Gd0.3(MoO4)8 (x = 0.0 to 1.0) phosphors, XRD, SEM, and FTIR spectra were used to characterize the materials, and their optical properties were thoroughly investigated. PL studies were examined at different excitations 230 nm, 275nm, 465nm, and 395 nm. All the spectra show similar emissions with the highest transition at 616 nm due to ED transition. The given phosphor Li¬3BaSr0.25Ca0.75Eu2.7Gd0.3(MoO4)8 shows the highest intensity and is thus chosen for the temperature-dependent and Quantum yield study. According to the PL investigation, the phosphor-containing Eu3+ emits red light due to the (5D0 7F2) transition. The excitation analysis shows that all of the Eu3+ activated phosphors exhibited broad absorption due to the charge transfer band, O2-Mo6+, O2-Eu3+ transition, as well as narrow absorption bands related to the Eu3+ ion's 4f-4f electronic transition. Excitation spectra show Charge transfer band at 275 nm shows the highest intensity. The primary band in the spectra refers to Eu3+ ions occupying the lattice's non-centrosymmetric location. All of the compositions are monoclinic crystal structures with space group C2/c and match with reference powder patterns. The thermal stability of the 3BaSr0.25Ca0.75Eu2.7Gd0.3(MoO4)8 phosphor was investigated at (300 k- 500 K) as well as at low temperature from (20 K to 275 K) to be utilized for red and white LED fabrication. The Decay Lifetime of all the phosphor was measured. The best phosphor was used for White and Red LED fabrication.

Keywords: PL, phosphor, quantum yield, white LED

Procedia PDF Downloads 50

Authors: Iris Alkaher, Nurit Carmi

Abstract:

It is widely agreed among scientists that population growth (PG) is a major factor that drives the global environmental crisis. Many researchers recognize that explicitly addressing the impact of PG on the environment and human quality of life through education systems worldwide could play a significant role in improving understanding regarding the links between rapid PG and environmental degradation and changing perceptions, attitudes, and behaviors concerning the necessity to reduce the fertility rate. However, the issue of PG is still rarely included in schools' curricula, mainly because of its complexity and controversiality. This study aims to explore the perspectives of teachers with an academic background in environmental and sustainability education (ESEteachers) and teachers with no such background (non-ESE teachers) regarding PG as an environmental risk. The study also explores the teachers’ willingness to include PG in their teaching and identifies what predicts their inclusion of it. In this mixed-methods research study, data were collected using questionnaires and interviews. The findings portray a complex picture concerning the debate aboutPG as a major factor that drives the global environmental crisis in the Israeli context. Consistent with other countries, we found that the deep-rooted pronatalist culture in the Israeli society, as well as a robust national pronatalist agenda and policies, have a tremendous impact on the education system. Therefore, we found that an academic background in ESE had a limited impact on teachers' perceptions concerning PG as a problem and on their willingness to include it in their teaching and discuss its controversiality. Teachers' attitudes related to PG demonstrated social, cultural, and politically oriented disavowal justification regarding the negative impacts of rapid PG, identified in the literature as population-skepticism and population-fatalism. Specifically, factors such as the ongoing Israeli-Palestinian conflict, the Jewish anxiety of destruction, and the religious command to“be fruitful and multiply”influenced the perceptions of both ESE and non-ESE teachers. While these arguments are unique to the Israeli context, pronatalist policies are international. In accordance with the pronatalist policy, we also found that the absence of PG from both school curricula and the Israeli public discourse was reported by ESE and non-ESE teachers as major reasons for their disregarding PG in their teaching. Under these circumstances, the role of the education system to bring the population question to the front stage in Israel and elsewhere is more challenging. To encourage science and social studies teachers to incorporate the controversial issue of PG in their teaching and successfully confront dominant pronatalist cultures, they need strong and ongoing scaffolding and support. In accordance with scientists' agreement regarding the role of PG as a major factor that drives the global environmental crisis, we call on stakeholders and policymakers in the education system to bring the population debate into schools' curricula, the sooner, the better. And not only as part of human efforts to mitigate environmental degradation but also to use this controversial topic as a platform for shaping critical learners and responsible and active citizens who are tolerant of different people’s opinions.

Keywords: population growth, environmental and sustainability education, controversial environmental sustainability issues, pronatalism

Procedia PDF Downloads 84

Authors: Linlin Guo, Baofeng Li

Abstract:

Zhengzhou is a typical plain city with a high population density and a permanent population of 10 million, located in central China. The scale of this city is constantly expanding, and the urban form has changed dramatically by the accelerating process of urbanization, which makes a great effect on the urban microclimate. In order to study the influence of block morphology on urban micro-climate, air temperature, humidity, wind velocity and so on in three typical types of blocks in the center of Zhengzhou were collected, which was chosen to perform the fixed and mobile observation. After data handling and analysis, a series of graphs and diagrams were obtained to reflect the differences in the influence of different types of block morphology on the urban microclimate. These can provide targeted strategies for urban design to improve and regulate urban micro-climate.

Keywords: urban micro-climate, block morphology, fixed and mobile observation, urban design

Procedia PDF Downloads 221