Search results for: annual maximum rainfall
600 Batch and Dynamic Investigations on Magnesium Separation by Ion Exchange Adsorption: Performance and Cost Evaluation
Authors: Mohamed H. Sorour, Hayam F. Shaalan, Heba A. Hani, Eman S. Sayed
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Ion exchange adsorption has a long standing history of success for seawater softening and selective ion removal from saline sources. Strong, weak and mixed types ion exchange systems could be designed and optimized for target separation. In this paper, different types of adsorbents comprising zeolite 13X and kaolin, in addition to, poly acrylate/zeolite (AZ), poly acrylate/kaolin (AK) and stand-alone poly acrylate (A) hydrogel types were prepared via microwave (M) and ultrasonic (U) irradiation techniques. They were characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The developed adsorbents were evaluated on bench scale level and based on assessment results, a composite bed has been formulated for performance evaluation in pilot scale column investigations. Owing to the hydrogel nature of the partially crosslinked poly acrylate, the developed adsorbents manifested a swelling capacity of about 50 g/g. The pilot trials have been carried out using magnesium enriched Red Seawater to simulate Red Seawater desalination brine. Batch studies indicated varying uptake efficiencies, where Mg adsorption decreases according to the following prepared hydrogel types AU>AM>AKM>AKU>AZM>AZU, being 108, 107, 78, 69, 66 and 63 mg/g, respectively. Composite bed adsorbent tested in the up-flow mode column studies indicated good performance for Mg uptake. For an operating cycle of 12 h, the maximum uptake during the loading cycle approached 92.5-100 mg/g, which is comparable to the performance of some commercial resins. Different regenerants have been explored to maximize regeneration and minimize the quantity of regenerants including 15% NaCl, 0.1 M HCl and sodium carbonate. Best results were obtained by acidified sodium chloride solution. In conclusion, developed cation exchange adsorbents comprising clay or zeolite support indicated adequate performance for Mg recovery under saline environment. Column design operated at the up-flow mode (approaching expanded bed) is appropriate for such type of separation. Preliminary cost indicators for Mg recovery via ion exchange have been developed and analyzed.Keywords: batch and dynamic magnesium separation, seawater, polyacrylate hydrogel, cost evaluation
Procedia PDF Downloads 135599 Results of Three-Year Operation of 220kV Pilot Superconducting Fault Current Limiter in Moscow Power Grid
Authors: M. Moyzykh, I. Klichuk, L. Sabirov, D. Kolomentseva, E. Magommedov
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Modern city electrical grids are forced to increase their density due to the increasing number of customers and requirements for reliability and resiliency. However, progress in this direction is often limited by the capabilities of existing network equipment. New energy sources or grid connections increase the level of short-circuit currents in the adjacent network, which can exceed the maximum rating of equipment–breaking capacity of circuit breakers, thermal and dynamic current withstand qualities of disconnectors, cables, and transformers. Superconducting fault current limiter (SFCL) is a modern solution designed to deal with the increasing fault current levels in power grids. The key feature of this device is its instant (less than 2 ms) limitation of the current level due to the nature of the superconductor. In 2019 Moscow utilities installed SuperOx SFCL in the city power grid to test the capabilities of this novel technology. The SFCL became the first SFCL in the Russian energy system and is currently the most powerful SFCL in the world. Modern SFCL uses second-generation high-temperature superconductor (2G HTS). Despite its name, HTS still requires low temperatures of liquid nitrogen for operation. As a result, Moscow SFCL is built with a cryogenic system to provide cooling to the superconductor. The cryogenic system consists of three cryostats that contain a superconductor part and are filled with liquid nitrogen (three phases), three cryocoolers, one water chiller, three cryopumps, and pressure builders. All these components are controlled by an automatic control system. SFCL has been continuously operating on the city grid for over three years. During that period of operation, numerous faults occurred, including cryocooler failure, chiller failure, pump failure, and others (like a cryogenic system power outage). All these faults were eliminated without an SFCL shut down due to the specially designed cryogenic system backups and quick responses of grid operator utilities and the SuperOx crew. The paper will describe in detail the results of SFCL operation and cryogenic system maintenance and what measures were taken to solve and prevent similar faults in the future.Keywords: superconductivity, current limiter, SFCL, HTS, utilities, cryogenics
Procedia PDF Downloads 83598 “Environmental-Friendly” and “People-Friendly” Project for a New North-East Italian Hospital
Authors: Emanuela Zilli, Antonella Ruffatto, Davide Bonaldo, Stefano Bevilacqua, Tommaso Caputo, Luisa Fontana, Carmelina Saraceno, Antonio Sturaroo, Teodoro Sava, Antonio Madia
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The new Hospital in Cittadella - ULSS 6 Euganea Health Trust, in the North-East of Italy (400 beds, project completion date in 2026), will partially take the place of the existing building. Interesting features have been suggested in order to project a modern, “environmental-friendly” and “people-friendly” building. Specific multidisciplinary meetings (involving stakeholders and professionals with different backgrounds) have been organized on a periodic basis in order to guarantee the appropriate implementation of logistic and organizational solutions related to eco-sustainability, integration with the context, and the concept of “design for all” and “humanization of care.” The resulting building will be composed of organic shapes determined by the external environment (sun movement, climate, landscape, pre-existing buildings, roads) and the needs of the internal environment (areas of care and diagnostic-treatment paths reorganized with experience gained during the pandemic), with extensive use of renewable energy, solar panels, a 4th-generation heating system, sanitised and maintainable surfaces. There is particular attention to the quality of the staff areas, which include areas dedicated to psycho-physical well-being (relax points, yoga gym), study rooms, and a centralized conference room. Outdoor recreational spaces and gardens for music and watercolour therapy will be included; atai-chi gym is dedicated to oncology patients. Integration in the urban and social context is emphasized through window placement toward the gardens (maternal-infant, mental health, and rehabilitation wards). Service areas such as dialysis, radiology, and labs have views of the medieval walls, the symbol of the city’s history. The new building has been designed to pursue the maximum level of eco-sustainability, harmony with the environment, and integration with the historical, urban, and social context; the concept of humanization of care has been considered in all the phases of the project management.Keywords: environmental-friendly, humanization, eco-sustainability, new hospital
Procedia PDF Downloads 119597 Evaluation of Reservoir Quality in Cretaceous Sandstone Complex, Western Flank of Anambra Basin, Southern Nigeria
Authors: Bayole Omoniyi
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This study demonstrates the value of outcrops as analogues for evaluating reservoir quality of sandbody in a typical high-sinuosity fluvial system. The study utilized data acquired from selected outcrops in the Campanian-Maastrichtian siliciclastic succession of the western flank of Anambra Basin, southern Nigeria. Textural properties derived from outcrop samples were correlated and compared with porosity and permeability using established standard charts. Porosity was estimated from thin sections of selected samples to reduce uncertainty in the estimates. Following facies classification, 14 distinct facies were grouped into three facies associations (FA1-FA3) and were subsequently modeled as discrete properties in a block-centered Cartesian grid on a scale that captures geometry of principal sandbodies. Porosity and permeability estimated from charts were populated in the grid using comparable geostatistical techniques that reflect their spatial distribution. The resultant models were conditioned to facies property to honour available data. The results indicate a strong control of geometrical parameters on facies distribution, lateral continuity and connectivity with resultant effect on porosity and permeability distribution. Sand-prone FA1 and FA2 display reservoir quality that varies internally from channel axis to margin in each succession. Furthermore, isolated stack pattern of sandbodies reduces static connectivity and thus, increases risk of poor communication between reservoir-quality sandbodies. FA3 is non-reservoir because it is mud-prone. In conclusion, the risk of poor communication between sandbodies may be effectively accentuated in reservoirs that have similar architecture because of thick lateral accretion deposits, usually mudstone, that tend to disconnect good-quality point-bar sandbodies. In such reservoirs, mudstone may act as a barrier to impede flow vertically from one sandbody to another and laterally at the margins of each channel-fill succession in the system. The development plan, therefore, must be designed to effectively mitigate these risks and the risk of stratigraphic compartmentalization for maximum hydrocarbon recovery.Keywords: analogues, architecture, connectivity, fluvial
Procedia PDF Downloads 27596 In Silico Analysis of Salivary miRNAs to Identify the Diagnostic Biomarkers for Oral Cancer
Authors: Andleeb Zahra, Itrat Rubab, Sumaira Malik, Amina Khan, Muhammad Jawad Khan, M. Qaiser Fatmi
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Oral squamous cell carcinoma (OSCC) is one of the most common cancers worldwide. Recent studies have highlighted the role of miRNA in disease pathology, indicating its potential use in an early diagnostic tool. miRNAs are small, double stranded, non-coding RNAs that regulate gene expression by deregulating mRNAs. miRNAs play important roles in modifying various cellular processes such as cell growth, differentiation, apoptosis, and immune response. Dis-regulated expression of miRNAs is known to affect the cell growth, and this may function as tumor suppressors or oncogenes in various cancers. Objectives: The main objectives of this study were to characterize the extracellular miRNAs involved in oral cancer (OC) to assist early detection of cancer as well as to propose a list of genes that can potentially be used as biomarkers of OC. We used gene expression data by microarrays already available in literature. Materials and Methods: In the first step, a total of 318 miRNAs involved in oral carcinoma were shortlisted followed by the prediction of their target genes. Simultaneously, the differentially expressed genes (DEGs) of oral carcinoma from all experiments were identified. The common genes between lists of DEGs of OC based on experimentally proven data and target genes of each miRNA were identified. These common genes are the targets of specific miRNA, which is involved in OC. Finally, a list of genes was generated which may be used as biomarker of OC. Results and Conclusion: In results, we included some of pathways in cancer to show the change in gene expression under the control of specific miRNA. Ingenuity pathway analysis (IPA) provided a list of major biomarkers like CDH2, CDK7 and functional enrichment analysis identified the role of miRNA in major pathways like cell adhesion molecules pathway affected by cancer. We observed that at least 25 genes are regulated by maximum number of miRNAs, and thereby, they can be used as biomarkers of OC. To better understand the role of miRNA with respect to their target genes further experiments are required, and our study provides a platform to better understand the miRNA-OC relationship at genomics level.Keywords: biomarkers, gene expression, miRNA, oral carcinoma
Procedia PDF Downloads 376595 Soft Robotic System for Mechanical Stimulation of Scaffolds During Dynamic Cell Culture
Authors: Johanna Perdomo, Riki Lamont, Edmund Pickering, Naomi C. Paxton, Maria A. Woodruff
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Background: Tissue Engineering (TE) has combined advanced materials, such as biomaterials, to create affordable scaffolds and dynamic systems to generate stimulation of seeded cells on these scaffolds, improving and maintaining the cellular growth process in a cell culture. However, Few TE skin products have been clinically translated, and more research is required to produce highly biomimetic skin substitutes that mimic the native elasticity of skin in a controlled manner. Therefore, this work will be focused on the fabrication of a novel mechanical system to enhance the TE treatment approaches for the reparation of damaged tissue skin. Aims: To archive this, a soft robotic device will be created to emulate different deformation of skin stress. The design of this soft robot will allow the attachment of scaffolds, which will then be mechanically actuated. This will provide a novel and highly adaptable platform for dynamic cell culture. Methods: Novel, low-cost soft robot is fabricated via 3D printed moulds and silicone. A low cost, electro-mechanical device was constructed to actuate the soft robot through the controlled combination of positive and negative air pressure to control the different state of movements. Mechanical tests were conducted to assess the performance and calibration of each electronic component. Similarly, pressure-displacement test was performed on scaffolds, which were attached to the soft robot, applying various mechanical loading regimes. Lastly, digital image correlation test was performed to obtain strain distributions over the soft robot’s surface. Results: The control system can control and stabilise positive pressure changes for long hours. Similarly, pressure-displacement test demonstrated that scaffolds with 5µm of diameter and wavy geometry can displace at 100%, applying a maximum pressure of 1.5 PSI. Lastly, during the inflation state, the displacement of silicone was measured using DIC method, and this showed a parameter of 4.78 mm and strain of 0.0652. Discussion And Conclusion: The developed soft robot system provides a novel and low-cost platform for the dynamic actuation of tissue scaffolds with a target towards dynamic cell culture.Keywords: soft robot, tissue engineering, mechanical stimulation, dynamic cell culture, bioreactor
Procedia PDF Downloads 96594 Caffeic Acid Methyl and Ethyl Esters Exhibit Beneficial Effect on Glucose and Lipid Metabolism in Cultured Murine Insulin-Sensitive Cells
Authors: Hoda M. Eid, Abir Nachar, Farah Thong, Gary Sweeney, Pierre S. Haddad
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Caffeic acid methyl ester (CAME) and caffeic ethyl esters (CAEE) were previously reported to potently stimulate glucose uptake in cultured C2C12 skeletal muscle cells via insulin-independent mechanisms involving the activation of adenosine monophosphate-activated protein kinase (AMPK). In the present study, we investigated the effect of the two compounds on the translocation of glucose transporter GLUT4 in L6 skeletal muscle cells. The cells were treated with the optimum non-toxic concentration (50 µM) of either CAME or CAEE for 18 h. Levels of GLUT4myc at the cell surface were measured by O-phenylenediamine dihydrochloride (OPD) assay. The effects of CAME and CAEE on GLUT1 and GLUT4 protein content were also measured by western immunoblot. Our results show that CAME and CAEE significantly increased glucose uptake, GLUT4 translocation and GLUT4 protein content. Furthermore, the effect of the two CA esters on two insulin-sensitive cell lines: H4IIE rat hepatoma and 3T3-L1 adipocytes were investigated. CAME and CAEE reduced the enzymatic activity of the key hepatic gluconeogenic enzyme glucose-6-phosphatase in a concentration-dependent manner. In addition, they exerted a concentration-dependent antiadipogenic effect on 3T3-L1 cells. Mitotic clonal expansion (MCE), a prerequisite for adipocytes differentiation was also concentration-dependently inhibited. The two compounds abrogated lipid droplet accumulation, blocked MCE and maintained cells in fibroblast-like state when applied at the maximum non-toxic concentration (100 µM). In addition, the expression of the early key adipogenic transcription factors CCAAT enhancer-binding protein beta (C/EBP-β) and the master regulator of adipogenesis peroxisome-proliferator-activated receptor gamma (PPAR-γ) were inhibited. We, therefore, conclude that CAME and CAEE exert pleiotropic benefits in several insulin-sensitive cell lines through insulin-independent mechanisms involving AMPK, hence they may treat obesity, diabetes and other metabolic diseases.Keywords: type 2 diabetes mellitus, insulin resistance, GLUT4, Akt, AMPK.
Procedia PDF Downloads 309593 Sustainable Valorization of Wine Production Waste: Unlocking the Potential of Grape Pomace and Lees in the Vinho Verde Region
Authors: Zlatina Genisheva, Pedro Ferreira-Santos, Margarida Soares, Cândida Vilarinho, Joana Carvalho
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The wine industry produces significant quantities of waste, much of which remains underutilized as a potential raw material. Typically, this waste is either discarded in the fields or incinerated, leading to environmental concerns. By-products of wine production, like lees and grape pomace, are readily available at relatively low costs and hold promise as raw materials for biochemical conversion into valuable products. Reusing these waste materials is crucial, not only for reducing environmental impact but also for enhancing profitability. The Vinhos Verdes demarcated region, the largest wine-producing area in Portugal, has remained relatively stagnant over time. This project aims to offer an alternative income source for producers in the region while also expanding the limited existing research on this area. The main objective of this project is the study of the sustainable valorization of grape pomace and lees from the production of DOC Vinho Verde. Extraction tests were performed to obtain high-value compounds, targeting phenolic compounds from grape pomace and protein-rich extracts from lees. An environmentally friendly technique, microwave extraction, was used for this process. This method is not only efficient but also aligns with the principles of green chemistry, reducing the use of harmful solvents and minimizing energy consumption. The findings from this study have the potential to open new revenue streams for the region’s wine producers while promoting environmental sustainability. The optimal conditions for extracting proteins from lees involve the use of NaOH at 150ºC. Regardless of the solvent employed, the ideal temperature for obtaining extracts rich in polyphenol compounds and exhibiting strong antioxidant activity is also 150ºC. For grape pomace, extracts with a high concentration of polyphenols and significant antioxidant properties were obtained at 210ºC. However, the highest total tannin concentrations were achieved at 150ºC, while the maximum total flavonoid content was obtained at 170ºC.Keywords: antioxidants, circular economy, polyphenol compounds, waste valorization
Procedia PDF Downloads 21592 The Relationships between Carbon Dioxide (CO2) Emissions, Energy Consumption and GDP for Iran: Time Series Analysis, 1980-2010
Authors: Jinhoa Lee
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The relationships between environmental quality, energy use and economic output have created growing attention over the past decades among researchers and policy makers. Focusing on the empirical aspects of the role of carbon dioxide (CO2) emissions and energy use in affecting the economic output, this paper is an effort to fulfill the gap in a comprehensive case study at a country level using modern econometric techniques. To achieve the goal, this country-specific study examines the short-run and long-run relationships among energy consumption (using disaggregated energy sources: Crude oil, coal, natural gas, and electricity), CO2 emissions and gross domestic product (GDP) for Iran using time series analysis from the year 1980-2010. To investigate the relationships between the variables, this paper employs the Augmented Dickey-Fuller (ADF) test for stationarity, Johansen’s maximum likelihood method for cointegration and a Vector Error Correction Model (VECM) for both short- and long-run causality among the research variables for the sample. All the variables in this study show very strong significant effects on GDP in the country for the long term. The long-run equilibrium in VECM suggests that all energy consumption variables in this study have significant impacts on GDP in the long term. The consumption of petroleum products and the direct combustion of crude oil and natural gas decrease GDP, while the coal and electricity use enhanced the GDP between 1980-2010 in Iran. In the short term, only electricity use enhances the GDP as well as its long-run effects. All variables of this study, except the CO2 emissions, show significant effects on the GDP in the country for the long term. The long-run equilibrium in VECM suggests that the consumption of petroleum products and the direct combustion of crude oil and natural gas use have positive impacts on the GDP while the consumptions of electricity and coal have adverse impacts on the GDP in the long term. In the short run, electricity use enhances the GDP over period of 1980-2010 in Iran. Overall, the results partly support arguments that there are relationships between energy use and economic output, but the associations can be differed by the sources of energy in the case of Iran over period of 1980-2010. However, there is no significant relationship between the CO2 emissions and the GDP and between the CO2 emissions and the energy use both in the short term and long term.Keywords: CO2 emissions, energy consumption, GDP, Iran, time series analysis
Procedia PDF Downloads 592591 Surface Display of Lipase on Yarrowia lipolytica Cells
Authors: Evgeniya Y. Yuzbasheva, Tigran V. Yuzbashev, Natalia I. Perkovskaya, Elizaveta B. Mostova
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Cell-surface display of lipase is of great interest as it has many applications in the field of biotechnology owing to its unique advantages: simplified product purification, and cost-effective downstream processing. One promising area of application for whole-cell biocatalysts with surface displayed lipase is biodiesel synthesis. Biodiesel is biodegradable, renewable, and nontoxic alternative fuel for diesel engines. Although the alkaline catalysis method has been widely used for biodiesel production, it has a number of limitations, such as rigorous feedstock specifications, complicated downstream processes, including removal of inorganic salts from the product, recovery of the salt-containing by-product glycerol, and treatment of alkaline wastewater. Enzymatic synthesis of biodiesel can overcome these drawbacks. In this study, Lip2p lipase was displayed on Yarrowia lipolytica cells via C- and N-terminal fusion variant. The active site of lipase is located near the C-terminus, therefore to prevent the activity loosing the insertion of glycine-serine linker between Lip2p and C-domains was performed. The hydrolytic activity of the displayed lipase reached 12,000–18,000 U/g of dry weight. However, leakage of enzyme from the cell wall was observed. In case of C-terminal fusion variant, the leakage was occurred due to the proteolytic cleavage within the linker peptide. In case of N-terminal fusion variant, the leaking enzyme was presented as three proteins, one of which corresponded to the whole hybrid protein. The calculated number of recombinant enzyme displayed on the cell surface is approximately 6–9 × 105 molecules per cell, which is close to the theoretical maximum (2 × 106 molecules/cell). Thus, we attribute the enzyme leakage to the limited space available on the cell surface. Nevertheless, cell-bound lipase exhibited greater stability to short-term and long-term temperature treatment than the native enzyme. It retained 74% of original activity at 60°C for 5 min of incubation, and 83% of original activity after incubation at 50°C during 5 h. Cell-bound lipase had also higher stability in organic solvents and detergents. The developed whole-cell biocatalyst was used for recycling biodiesel synthesis. Two repeated cycles of methanolysis yielded 84.1–% and 71.0–% methyl esters after 33–h and 45–h reactions, respectively.Keywords: biodiesel, cell-surface display, lipase, whole-cell biocatalyst
Procedia PDF Downloads 483590 Robust Numerical Method for Singularly Perturbed Semilinear Boundary Value Problem with Nonlocal Boundary Condition
Authors: Habtamu Garoma Debela, Gemechis File Duressa
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In this work, our primary interest is to provide ε-uniformly convergent numerical techniques for solving singularly perturbed semilinear boundary value problems with non-local boundary condition. These singular perturbation problems are described by differential equations in which the highest-order derivative is multiplied by an arbitrarily small parameter ε (say) known as singular perturbation parameter. This leads to the existence of boundary layers, which are basically narrow regions in the neighborhood of the boundary of the domain, where the gradient of the solution becomes steep as the perturbation parameter tends to zero. Due to the appearance of the layer phenomena, it is a challenging task to provide ε-uniform numerical methods. The term 'ε-uniform' refers to identify those numerical methods in which the approximate solution converges to the corresponding exact solution (measured to the supremum norm) independently with respect to the perturbation parameter ε. Thus, the purpose of this work is to develop, analyze, and improve the ε-uniform numerical methods for solving singularly perturbed problems. These methods are based on nonstandard fitted finite difference method. The basic idea behind the fitted operator, finite difference method, is to replace the denominator functions of the classical derivatives with positive functions derived in such a way that they capture some notable properties of the governing differential equation. A uniformly convergent numerical method is constructed via nonstandard fitted operator numerical method and numerical integration methods to solve the problem. The non-local boundary condition is treated using numerical integration techniques. Additionally, Richardson extrapolation technique, which improves the first-order accuracy of the standard scheme to second-order convergence, is applied for singularly perturbed convection-diffusion problems using the proposed numerical method. Maximum absolute errors and rates of convergence for different values of perturbation parameter and mesh sizes are tabulated for the numerical example considered. The method is shown to be ε-uniformly convergent. Finally, extensive numerical experiments are conducted which support all of our theoretical findings. A concise conclusion is provided at the end of this work.Keywords: nonlocal boundary condition, nonstandard fitted operator, semilinear problem, singular perturbation, uniformly convergent
Procedia PDF Downloads 143589 The Preceptorship Experience and Clinical Competence of Final Year Nursing Students
Authors: Susan Ka Yee Chow
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Effective clinical preceptorship is affecting students’ competence and fostering their growth in applying theoretical knowledge and skills in clinical settings. Any difference between the expected and actual learning experience will reduce nursing students’ interest in clinical practices and having a negative consequence with their clinical performance. This cross-sectional study is an attempt to compare the differences between preferred and actual preceptorship experience of final year nursing students, and to examine the relationship between the actual preceptorship experience and perceived clinical competence of the students in a tertiary institution. Participants of the study were final year bachelor nursing students of a self-financing tertiary institution in Hong Kong. The instruments used to measure the effectiveness of clinical preceptorship was developed by the participating institution. The scale consisted of five items in a 5-point likert scale. The questions including goals development, critical thinking, learning objectives, asking questions and providing feedback to students. The “Clinical Competence Questionnaire” by Liou & Cheng (2014) was used to examine students’ perceived clinical competences. The scale consisted of 47 items categorized into four domains, namely nursing professional behaviours; skill competence: general performance; skill competence: core nursing skills and skill competence: advanced nursing skills. There were 193 questionnaires returned with a response rate of 89%. The paired t-test was used to compare the differences between preferred and actual preceptorship experiences of students. The results showed significant differences (p<0.001) for the five questions. The mean for the preferred scores is higher than the actual scores resulting statistically significance. The maximum mean difference was accepted goal and the highest mean different was giving feedback. The Pearson Correlation Coefficient was used to examine the relationship. The results showed moderate correlations between nursing professional behaviours with asking questions and providing feedback. Providing useful feedback to students is having moderate correlations with all domains of the Clinical Competence Questionnaire (r=0.269 – 0.345). It is concluded that nursing students do not have a positive perception of the clinical preceptorship. Their perceptions are significantly different from their expected preceptorship. If students were given more opportunities to ask questions in a pedagogical atmosphere, their perceived clinical competence and learning outcomes could be improved as a result.Keywords: clinical preceptor, clinical competence, clinical practicum, nursing students
Procedia PDF Downloads 127588 Assesment of Genetic Fidelity of Micro-Clones of an Aromatic Medicinal Plant Murraya koenigii (L.) Spreng
Authors: Ramesh Joshi, Nisha Khatik
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Murraya koenigii (L.) Spreng locally known as “Curry patta” or “Meetha neem” belonging to the family Rutaceae that grows wildly in Southern Asia. Its aromatic leaves are commonly used as the raw material for traditional medicinal formulations in India. The leaves contain essential oil and also used as a condiment. Several monomeric and binary carbazol alkaloids present in the various plant parts. These alkaloids have been reported to possess anti-microbial, mosquitocidal, topo-isomerase inhibition and antioxidant properties. Some of the alkaloids reported in this plant have showed anti carcinogenic and anti-diabetic properties. The conventional method of propagation of this tree is limited to seeds only, which retain their viability for only a short period. Hence, a biotechnological approach might have an advantage edging over traditional breeding as well as the genetic improvement of M. koenigii within a short period. The development of a reproducible regeneration protocol is the prerequisite for ex situ conservation and micropropagation. An efficient protocol for high frequency regeneration of in vitro plants of Murraya koenigii via different explants such as- nodal segments, intermodal segments, leaf, root segments, hypocotyle, cotyledons and cotyledonary node explants is described. In the present investigation, assessment of clonal fidelity in the micropropagated plantlets of Murraya koenigii was attempted using RAPD and ISSR markers at different pathways of plant tissue culture technique. About 20 ISSR and 40 RAPD primers were used for all the samples. Genomic DNA was extracted by CTAB method. ISSR primer were found to be more suitable as compared to RAPD for the analysis of clonal fidelity of M. koenigii. The amplifications however, were finally performed using RAPD, ISSR markers owing to their better performance in terms of generation of amplification products. In RAPD primer maximum 75% polymorphism was recorded in OPU-2 series which exhibited out of 04 scorable bands, three bands were polymorphic with a band range of size 600-1500 bp. In ISSR primers the UBC 857 showed 50% polymorphism with 02 band were polymorphic of band range size between 400-1000 bp.Keywords: genetic fidelity, Murraya koenigii, aromatic plants, ISSR primers
Procedia PDF Downloads 502587 Evidence of a Negativity Bias in the Keywords of Scientific Papers
Authors: Kseniia Zviagintseva, Brett Buttliere
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Science is fundamentally a problem-solving enterprise, and scientists pay more attention to the negative things, that cause them dissonance and negative affective state of uncertainty or contradiction. While this is agreed upon by philosophers of science, there are few empirical demonstrations. Here we examine the keywords from those papers published by PLoS in 2014 and show with several sentiment analyzers that negative keywords are studied more than positive keywords. Our dataset is the 927,406 keywords of 32,870 scientific articles in all fields published in 2014 by the journal PLOS ONE (collected from Altmetric.com). Counting how often the 47,415 unique keywords are used, we can examine whether those negative topics are studied more than positive. In order to find the sentiment of the keywords, we utilized two sentiment analysis tools, Hu and Liu (2004) and SentiStrength (2014). The results below are for Hu and Liu as these are the less convincing results. The average keyword was utilized 19.56 times, with half of the keywords being utilized only 1 time and the maximum number of uses being 18,589 times. The keywords identified as negative were utilized 37.39 times, on average, with the positive keywords being utilized 14.72 times and the neutral keywords - 19.29, on average. This difference is only marginally significant, with an F value of 2.82, with a p of .05, but one must keep in mind that more than half of the keywords are utilized only 1 time, artificially increasing the variance and driving the effect size down. To examine more closely, we looked at those top 25 most utilized keywords that have a sentiment. Among the top 25, there are only two positive words, ‘care’ and ‘dynamics’, in position numbers 5 and 13 respectively, with all the rest being identified as negative. ‘Diseases’ is the most studied keyword with 8,790 uses, with ‘cancer’ and ‘infectious’ being the second and fourth most utilized sentiment-laden keywords. The sentiment analysis is not perfect though, as the words ‘diseases’ and ‘disease’ are split by taking 1st and 3rd positions. Combining them, they remain as the most common sentiment-laden keyword, being utilized 13,236 times. More than just splitting the words, the sentiment analyzer logs ‘regression’ and ‘rat’ as negative, and these should probably be considered false positives. Despite these potential problems, the effect is apparent, as even the positive keywords like ‘care’ could or should be considered negative, since this word is most commonly utilized as a part of ‘health care’, ‘critical care’ or ‘quality of care’ and generally associated with how to improve it. All in all, the results suggest that negative concepts are studied more, also providing support for the notion that science is most generally a problem-solving enterprise. The results also provide evidence that negativity and contradiction are related to greater productivity and positive outcomes.Keywords: bibliometrics, keywords analysis, negativity bias, positive and negative words, scientific papers, scientometrics
Procedia PDF Downloads 188586 Analyses of Defects in Flexible Silicon Photovoltaic Modules via Thermal Imaging and Electroluminescence
Authors: S. Maleczek, K. Drabczyk, L. Bogdan, A. Iwan
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It is known that for industrial applications using solar panel constructed from silicon solar cells require high-efficiency performance. One of the main problems in solar panels is different mechanical and structural defects, causing the decrease of generated power. To analyse defects in solar cells, various techniques are used. However, the thermal imaging is fast and simple method for locating defects. The main goal of this work was to analyze defects in constructed flexible silicon photovoltaic modules via thermal imaging and electroluminescence method. This work is realized for the GEKON project (No. GEKON2/O4/268473/23/2016) sponsored by The National Centre for Research and Development and The National Fund for Environmental Protection and Water Management. Thermal behavior was observed using thermographic camera (VIGOcam v50, VIGO System S.A, Poland) using a DC conventional source. Electroluminescence was observed by Steinbeis Center Photovoltaics (Stuttgart, Germany) equipped with a camera, in which there is a Si-CCD, 16 Mpix detector Kodak KAF-16803type. The camera has a typical spectral response in the range 350 - 1100 nm with a maximum QE of 60 % at 550 nm. In our work commercial silicon solar cells with the size 156 × 156 mm were cut for nine parts (called single solar cells) and used to create photovoltaic modules with the size of 160 × 70 cm (containing about 80 single solar cells). Flexible silicon photovoltaic modules on polyamides or polyester fabric were constructed and investigated taking into consideration anomalies on the surface of modules. Thermal imaging provided evidence of visible voltage-activated conduction. In electro-luminescence images, two regions are noticeable: darker, where solar cell is inactive and brighter corresponding with correctly working photovoltaic cells. The electroluminescence method is non-destructive and gives greater resolution of images thereby allowing a more precise evaluation of microcracks of solar cell after lamination process. Our study showed good correlations between defects observed by thermal imaging and electroluminescence. Finally, we can conclude that the thermographic examination of large scale photovoltaic modules allows us the fast, simple and inexpensive localization of defects at the single solar cells and modules. Moreover, thermographic camera was also useful to detection electrical interconnection between single solar cells.Keywords: electro-luminescence, flexible devices, silicon solar cells, thermal imaging
Procedia PDF Downloads 316585 Calcitriol Improves Plasma Lipoprotein Profile by Decreasing Plasma Total Cholesterol and Triglyceride in Hypercholesterolemic Golden Syrian Hamsters
Authors: Xiaobo Wang, Zhen-Yu Chen
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Higher plasma total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) are independent risk factors of cardiovascular disease while high-density lipoprotein cholesterol (HDL-C) is protective. Vitamin D is well-known for its regulatory role in calcium homeostasis. Its potential important role in cardiovascular disease has recently attracted much attention. This study was conducted to investigate effects of different dosage of calcitriol on plasma lipoprotein profile and the underlying mechanism. Sixty male Syrian Golden hamsters were randomly divided into 6 groups: no-cholesterol control (NCD), high-cholesterol control (HCD), groups with calcitriol supplementation at 10/20/40/80ng/kg body weight (CA, CB, CC, CD), respectively. Calcitriol in medium-chain triacylglycerol (MCT) oil was delivered to four experimental groups via oral gavage every other day, while NCD and HCD received MCT oil in the equivalent amount. NCD hamsters were fed with non-cholesterol diet while other five groups were maintained on diet containing 0.2% cholesterol to induce a hypercholesterolemic condition. The treatment lasts for 6 weeks followed by sample collection after hamsters sacrificed. Four experimental groups experienced a reduction in average food intake around 11% compared to HCD with slight decrease in body weight (not exceeding 10%). This reduction reflects on the deceased relative weights of testis, epididymal and perirenal adipose tissue in a dose-dependent manner. Plasma calcitriol levels were measured and was corresponding to oral gavage. At the end of week 6, lipoprotein profiles were improved with calcitriol supplementation with TC, non-HDL-C and plasma triglyceride (TG) decreased in a dose-dependent manner (TC: r=0.373, p=0.009, non-HDL-C: r=0.479, p=0.001, TG: r=0.405, p=0.004). Since HDL-C of four experiment groups showed no significant difference compared to HCD, the ratio of nHDL-C to HDL-C and HDL-C to TC had been restored in a dose-dependent manner. For hamsters receiving the highest level of calcitriol (80ng/kg) showed a reduction of TC by 11.5%, nHDL-C by 24.1% and TG by 31.25%. Little difference was found among six groups on the acetylcholine-induced endothelium-dependent relaxation or contraction of thoracic aorta. To summarize, calcitriol supplementation in hamster at maximum 80ng/kg body weight for 6 weeks lead to an overall improvement in plasma lipoprotein profile with decreased TC and TG level. The molecular mechanism of its effects is under investigation.Keywords: cholesterol, vitamin D, calcitriol, hamster
Procedia PDF Downloads 238584 Room Temperature Sensitive Broadband Terahertz Photo Response Using Platinum Telluride Based Devices
Authors: Alka Jakhar, Harmanpreet Kaur Sandhu, Samaresh Das
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The Terahertz (THz) technology-based devices are heightening at an alarming rate on account of the wide range of applications in imaging, security, communication, and spectroscopic field. The various available room operational THz detectors, including Golay cell, pyroelectric detector, field-effect transistors, and photoconductive antennas, have some limitations such as narrow-band response, slow response speed, transit time limits, and complex fabrication process. There is an urgent demand to explore new materials and device structures to accomplish efficient THz detection systems. Recently, TMDs including topological semimetals and topological insulators such as PtSe₂, MoTe₂, WSe₂, and PtTe₂ provide novel feasibility for photonic and optical devices. The peculiar properties of these materials, such as Dirac cone, fermions presence, nonlinear optical response, high conductivity, and ambient stability, make them worthy for the development of the THz devices. Here, the platinum telluride (PtTe₂) based devices have been demonstrated for THz detection in the frequency range of 0.1-1 THz. The PtTe₂ is synthesized by direct selenization of the sputtered platinum film on the high-resistivity silicon substrate by using the chemical vapor deposition (CVD) method. The Raman spectra, XRD, and XPS spectra confirm the formation of the thin PtTe₂ film. The PtTe₂ channel length is 5µm and it is connected with a bow-tie antenna for strong THz electric field confinement in the channel. The characterization of the devices has been carried out in a wide frequency range from 0.1-1 THz. The induced THz photocurrent is measured by using lock-in-amplifier after preamplifier. The maximum responsivity is achieved up to 1 A/W under self-biased mode. Further, this responsivity has been increased by applying biasing voltage. This photo response corresponds to low energy THz photons is mainly due to the photo galvanic effect in PtTe₂. The DC current is induced along the PtTe₂ channel, which is directly proportional to the amplitude of the incident THz electric field. Thus, these new topological semimetal materials provide new pathways for sensitive detection and sensing applications in the THz domain.Keywords: terahertz, detector, responsivity, topological-semimetals
Procedia PDF Downloads 161583 Relation Between Traffic Mix and Traffic Accidents in a Mixed Industrial Urban Area
Authors: Michelle Eliane Hernández-García, Angélica Lozano
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The traffic accidents study usually contemplates the relation between factors such as the type of vehicle, its operation, and the road infrastructure. Traffic accidents can be explained by different factors, which have a greater or lower relevance. Two zones are studied, a mixed industrial zone and the extended zone of it. The first zone has mainly residential (57%), and industrial (23%) land uses. Trucks are mainly on the roads where industries are located. Four sensors give information about traffic and speed on the main roads. The extended zone (which includes the first zone) has mainly residential (47%) and mixed residential (43%) land use, and just 3% of industrial use. The traffic mix is composed mainly of non-trucks. 39 traffic and speed sensors are located on main roads. The traffic mix in a mixed land use zone, could be related to traffic accidents. To understand this relation, it is required to identify the elements of the traffic mix which are linked to traffic accidents. Models that attempt to explain what factors are related to traffic accidents have faced multiple methodological problems for obtaining robust databases. Poisson regression models are used to explain the accidents. The objective of the Poisson analysis is to estimate a vector to provide an estimate of the natural logarithm of the mean number of accidents per period; this estimate is achieved by standard maximum likelihood procedures. For the estimation of the relation between traffic accidents and the traffic mix, the database is integrated of eight variables, with 17,520 observations and six vectors. In the model, the dependent variable is the occurrence or non-occurrence of accidents, and the vectors that seek to explain it, correspond to the vehicle classes: C1, C2, C3, C4, C5, and C6, respectively, standing for car, microbus, and van, bus, unitary trucks (2 to 6 axles), articulated trucks (3 to 6 axles) and bi-articulated trucks (5 to 9 axles); in addition, there is a vector for the average speed of the traffic mix. A Poisson model is applied, using a logarithmic link function and a Poisson family. For the first zone, the Poisson model shows a positive relation among traffic accidents and C6, average speed, C3, C2, and C1 (in a decreasing order). The analysis of the coefficient shows a high relation with bi-articulated truck and bus (C6 and the C3), indicating an important participation of freight trucks. For the expanded zone, the Poisson model shows a positive relation among traffic accidents and speed average, biarticulated truck (C6), and microbus and vans (C2). The coefficients obtained in both Poisson models shows a higher relation among freight trucks and traffic accidents in the first industrial zone than in the expanded zone.Keywords: freight transport, industrial zone, traffic accidents, traffic mix, trucks
Procedia PDF Downloads 130582 Propagation of Simmondsia chinensis (Link) Schneider by Stem Cuttings
Authors: Ahmed M. Eed, Adam H. Burgoyne
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Jojoba (Simmondsia chinensis (Link) Schneider), is a desert shrub which tolerates saline, alkyle soils and drought. The seeds contain a characteristic liquid wax of economic importance in industry as a machine lubricant and cosmetics. A major problem in seed propagation is that jojoba is a dioecious plant whose sex is not easily determined prior to flowering (3-4 years from germination). To overcome this phenomenon, asexual propagation using vegetative methods such as cutting can be used. This research was conducted to find out the effect of different Plant Growth Regulators (PGRs) and rooting media on Jojoba rhizogenesis. An experiment was carried out in a Factorial Completely Randomized Design (FCRD) with three replications, each with sixty cuttings per replication in fiberglass house of Natural Jojoba Corporation at Yemen. The different rooting media used were peat moss + perlite + vermiculite (1:1:1), peat moss + perlite (1:1) and peat moss + sand (1:1). Plant materials used were semi-hard wood cuttings of jojoba plants with length of 15 cm. The cuttings were collected in the month of June during 2012 and 2013 from the sub-terminal growth of the mother plants of Amman farm and introduced to Yemen. They were wounded, treated with Indole butyric acid (IBA), α-naphthalene acetic acid (NAA) or Indole-3-acetic acid (IAA) all @ 4000 ppm (part per million) and cultured on different rooting media under intermittent mist propagation conditions. IBA gave significantly higher percentage of rooting (66.23%) compared to NAA and IAA in all media used. However, the lowest percentage of rooting (5.33%) was recorded with IAA in the medium consisting of peat moss and sand (1:1). No significant difference was observed at all types of PGRs used with rooting media in respect of root length. Maximum number of roots was noticed in medium consisting of peat moss, perlite and vermiculite (1:1:1); peat moss and perlite (1:1) and peat moss and sand (1:1) using IBA, NAA and IBA, respectively. The interaction among rooting media was statistically significant with respect to rooting percentage character. Similarly, the interactions among PGRs were significant in terms of rooting percentage and also root length characters. The results demonstrated suitability of propagation of jojoba plants by semi-hard wood cuttings.Keywords: cutting, IBA, Jojoba, propagation, rhizogenesis
Procedia PDF Downloads 343581 Female Labor Force Participation in Iranian Rural Areas: An Inter-provincial Study
Authors: Zahra Mila Elmi, Mahsa Khanekheshi
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Almost half of the population and potential manpower in the country and rural areas are women. Manpower especially educated people, plays an important role in the production and economic growth. Also, the potential of rural areas to create employment should not be overlooked. In this research, the effects of socio-economic and demographic factors on women's economic participation in rural areas of Iran's provinces will be studied. Therefore, this study was performed by using the results of the rural households income and expenditure surveys -has been taken in 2016- in the framework of pseudo panel data. This study used the logit model and the maximum likelihood method to study the rural women's participation, with 28,265 observations. Results show the inverted U-shaped relationship between age and the probability of female participation; In other words, young women are more likely to participate in labor markets more than the other groups. Divorced and single woman has more chance of participation in comparison with who was being married. With increasing the divorce rate and singleness in Iran, economic policymakers must provide appropriate solutions for this challenge in the coming years. On the base of the results, being a student and the presence of an infant under the age of 6 in the household has a negative effect on the possibility of women's participation in the labor market. The women's education level has a U-shaped relationship with their participation rate. Illiteracy and high education have a strong positive effect on the economic participation of rural women. This shows the dual labor market for women in Iran. Illiterate women are attracted to service jobs, and educated woman are more attracted to education and health jobs. Increasing household income has a small but positive and significant effect on the probability of rural female participation. In the overlook, due to the frequency of the women population in the age group of 25 to 35 years, and more willingness of women in the age 35 to 44 years to participate in the labor market, and studying ofa significant portion of the rural women, the increase of rural female participation is expected in the years ahead. Thus, it is expected policy maker to create new job opportunities for the employment of educated women and take the necessary plan to improve the current situation for women.Keywords: female participation rate, rural area, provincial data, pseudo-panel data method
Procedia PDF Downloads 100580 Seismic Retrofit of Tall Building Structure with Viscous, Visco-Elastic, Visco-Plastic Damper
Authors: Nicolas Bae, Theodore L. Karavasilis
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Increasingly, a large number of new and existing tall buildings are required to improve their resilient performance against strong winds and earthquakes to minimize direct, as well as indirect damages to society. Those advent stationary functions of tall building structures in metropolitan regions can be severely hazardous, in socio-economic terms, which also increase the requirement of advanced seismic performance. To achieve these progressive requirements, the seismic reinforcement for some old, conventional buildings have become enormously costly. The methods of increasing the buildings’ resilience against wind or earthquake loads have also become more advanced. Up to now, vibration control devices, such as the passive damper system, is still regarded as an effective and an easy-to-install option, in improving the seismic resilience of buildings at affordable prices. The main purpose of this paper is to examine 1) the optimization of the shape of visco plastic brace damper (VPBD) system which is one of hybrid damper system so that it can maximize its energy dissipation capacity in tall buildings against wind and earthquake. 2) the verification of the seismic performance of the visco plastic brace damper system in tall buildings; up to forty-storey high steel frame buildings, by comparing the results of Non-Linear Response History Analysis (NLRHA), with and without a damper system. The most significant contribution of this research is to introduce the optimized hybrid damper system that is adequate for high rise buildings. The efficiency of this visco plastic brace damper system and the advantages of its use in tall buildings can be verified since tall buildings tend to be affected by wind load at its normal state and also by earthquake load after yielding of steel plates. The modeling of the prototype tall building will be conducted using the Opensees software. Three types of modeling were used to verify the performance of the damper (MRF, MRF with visco-elastic, MRF with visco-plastic model) 22-set seismic records used and the scaling procedure was followed according to the FEMA code. It is shown that MRF with viscous, visco-elastic damper, it is superior effective to reduce inelastic deformation such as roof displacement, maximum story drift, roof velocity compared to the MRF only.Keywords: tall steel building, seismic retrofit, viscous, viscoelastic damper, performance based design, resilience based design
Procedia PDF Downloads 193579 A Stepwise Approach for Piezoresistive Microcantilever Biosensor Optimization
Authors: Amal E. Ahmed, Levent Trabzon
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Due to the low concentration of the analytes in biological samples, the use of Biological Microelectromechanical System (Bio-MEMS) biosensors for biomolecules detection results in a minuscule output signal that is not good enough for practical applications. In response to this, a need has arisen for an optimized biosensor capable of giving high output signal in response the detection of few analytes in the sample; the ultimate goal is being able to convert the attachment of a single biomolecule into a measurable quantity. For this purpose, MEMS microcantilevers based biosensors emerged as a promising sensing solution because it is simple, cheap, very sensitive and more importantly does not need analytes optical labeling (Label-free). Among the different microcantilever transducing techniques, piezoresistive based microcantilever biosensors became more prominent because it works well in liquid environments and has an integrated readout system. However, the design of piezoresistive microcantilevers is not a straightforward problem due to coupling between the design parameters, constraints, process conditions, and performance. It was found that the parameters that can be optimized to enhance the sensitivity of Piezoresistive microcantilever-based sensors are: cantilever dimensions, cantilever material, cantilever shape, piezoresistor material, piezoresistor doping level, piezoresistor dimensions, piezoresistor position, Stress Concentration Region's (SCR) shape and position. After a systematic analyzation of the effect of each design and process parameters on the sensitivity, a step-wise optimization approach was developed in which almost all these parameters were variated one at each step while fixing the others to get the maximum possible sensitivity at the end. At each step, the goal was to optimize the parameter in a way that it maximizes and concentrates the stress in the piezoresistor region for the same applied force thus get the higher sensitivity. Using this approach, an optimized sensor that has 73.5x times higher electrical sensitivity (ΔR⁄R) than the starting sensor was obtained. In addition to that, this piezoresistive microcantilever biosensor it is more sensitive than the other similar sensors previously reported in the open literature. The mechanical sensitivity of the final senior is -1.5×10-8 Ω/Ω ⁄pN; which means that for each 1pN (10-10 g) biomolecules attach to this biosensor; the piezoresistor resistivity will decrease by 1.5×10-8 Ω. Throughout this work COMSOL Multiphysics 5.0, a commercial Finite Element Analysis (FEA) tool, has been used to simulate the sensor performance.Keywords: biosensor, microcantilever, piezoresistive, stress concentration region (SCR)
Procedia PDF Downloads 571578 An Evaluation of Medical Waste in Health Facilities through Data Envelopment Analysis (DEA) Method: Turkey-Amasya Public Hospitals Union Model
Authors: Murat Iskender Aktaş, Sadi Ergin, Rasime Acar Aktaş
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In the light of fast-paced changes and developments in the health sector, the Ministry of Health started a new structuring with decree law numbered 663 within the scope of the Project of Transformation in Health. Accordingly, hospitals should ensure patient satisfaction through more efficient, more effective use of resources and sustainable finance by placing patients in the centre and should operate to increase efficiency to its maximum level while doing these. Within this study, in order to find out how efficient the hospitals were in terms of medical waste management between the years 2011-2014, the data from six hospitals of Amasya Public Hospitals Union were evaluated separately through Data Envelopment Analysis (DEA) method. First of all, input variables were determined. Input variables were the number of patients admitted to polyclinics, the number of inpatients in clinics, the number of patients who were operated and the number of patients who applied to the laboratory. Output variable was the cost of medical wastes in Turkish liras. Each hospital’s total medical waste level before and after public hospitals union; the amounts of average medical waste per patient admitted to polyclinics, per inpatient in clinics, per patient admitted to laboratory and per operated patient were compared within each group. In addition, average medical waste levels and costs were compared for Turkey in general and Europe in general. Paired samples t-test was used to find out whether the changes (increase-decrease) after public hospitals union were statistically significant. The health facilities that were unsuccessful in terms of medical waste management before and after public hospital union and the factors that caused this failure were determined. Based on the results, for each health facility that was ineffective in terms of medical waste management, the level of improvement required for each input was determined. The results of the study showed that there was an improvement in medical waste management applications after the health facilities became a member of public hospitals union; their medical waste levels were lower than the average of Turkey and Europe while the averages of cost of disposal were the highest.Keywords: medical waste management, cost of medical waste, public hospitals, data envelopment analysis
Procedia PDF Downloads 416577 Structural Property and Mechanical Behavior of Polypropylene–Elemental Sulfur (S8) Composites: Effect of Sulfur Loading
Authors: S. Vijay Kumar, Kishore K. Jena, Saeed M. Alhassan
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Elemental sulfur is currently produced on the level of 70 million tons annually by petroleum refining, majority of which is used in the production of sulfuric acid, fertilizer and other chemicals. Still, over 6 million tons of elemental sulfur is generated in excess, which creates exciting opportunities to develop new chemistry to utilize sulfur as a feedstock for polymers. Development of new polymer composite materials using sulfur is not widely explored and remains an important challenge in the field. Polymer nanocomposites prepared by carbon nanotube, graphene, silica and other nanomaterials were well established. However, utilization of sulfur as filler in the polymer matrix could be an interesting study. This work is to presents the possibility of utilizing elemental sulfur as reinforcing fillers in the polymer matrix. In this study we attempted to prepare polypropylene/sulfur nanocomposite. The physical, mechanical and morphological properties of the newly developed composites were studied according to the sulfur loading. In the sample preparation, four levels of elemental sulfur loading (5, 10, 20 and 30 wt. %) were designed. Composites were prepared by the melt mixing process by using laboratory scale mini twin screw extruder at 180°C for 15 min. The reaction time and temperature were maintained constant for all prepared composites. The structure and crystallization behavior of composites was investigated by Raman, FTIR, XRD and DSC analysis. It was observed that sulfur interfere with the crystalline arrangement of polypropylene and depresses the crystallization, which affects the melting point, mechanical and thermal stability. In the tensile test, one level of test temperature (room temperature) and crosshead speed (10 mm/min) was designed. Tensile strengths and tensile modulus of the composites were slightly decreased with increasing in filler loading, however, percentage of elongation improved by more than 350% compared to neat polypropylene. The effect of sulfur on the morphology of polypropylene was studied with TEM and SEM techniques. Microscope analysis revels that sulfur is homogeneously dispersed in polymer matrix and behaves as single phase arrangement in the polymer. The maximum elongation for the polypropylene can be achieved by adjusting the sulfur loading in the polymer. This study reviles the possibility of using elemental sulfur as a solid plasticizer in the polypropylene matrix.Keywords: crystallization, elemental sulfur, morphology, thermo-mechanical properties, polypropylene, polymer nanocomposites
Procedia PDF Downloads 347576 Seasonal Variations, Environmental Parameters, and Standing Crop Assessment of Benthic Foraminifera in Western Bahrain, Arabian Gulf
Authors: Muhammad Arslan, Michael A. Kaminski, Bassam S. Tawabini, Fabrizio Frontalini
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We conducted a survey of living benthic foraminifera in a relatively unpolluted site of Bahrain in the Arabian Gulf, with the aim of determining the seasonal variability in their populations, as well as various environmental parameters that affect their distribution. The maximum standing crop was observed during winter, with highest population of rotaliids, followed by a peak in miliolids. The highest population is attributed to an increasing number juveniles observed along the depth transect. A strong correlation between sediment grain size and the foraminiferal population indicates that juveniles were most abundant on coarser sandy substrate and less abundant on fine substrate. In spring, the total living population decreased, and lowest values are observed in the summer. The population started to increase again in the autumn with highest juveniles/adult ratios. Moreover, results of relative abundance and species consistency show that Ammonia is found to be consistent from the shallowest to the deepest station, whereas miliolids start appearing in the deeper stations. The average numbers of Peneroplis and Elphidium also increases along the depth transect. Environmental characterization reveals that although the site is subjected to eutrophication caused by nitrates and sulfates, pollution caused by hydrocarbons and heavy metals is not significant. The assessment of 63 heavy metals showed that none of the metals had concentrations that exceed internationally accepted norms [the devised level of Effect Range-Low], with the exception of strontium. The lack of a significant environmental effect of heavy metals is confirmed by a Foraminiferal Deformities Index value of less than 2%. Likewise, no hydrocarbon contamination was detected in the water or sediment samples. Lastly, observations of cytoplasmic streaming and pseudopodial activity in Petri dishes suggest that the foraminiferal population is not stressed. We conclude that the site in Bahrain is not yet adversely affected by human development, and therefore can provide baseline information for future comparison and assessment of foraminiferal assemblages in contaminated zones of the Arabian Gulf.Keywords: Arabian Gulf, benthic foraminifera, standing crop, Western Bahrain
Procedia PDF Downloads 644575 Influential Factors Impacting the Utilization of Pain Assessment Tools among Hospitalized Elderly Patients in Taiwan
Authors: Huei Jiun Chen, Hui Mei Huan
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Introduction: Pain is an unpleasant experience for hospitalized patients that impacts both their physical and mental well-being. It is important to select appropriate pain assessment tools to ensure effective pain management. Therefore, it is suggested to use Verbal Rating Scale (VRS) instead for better assessment. The Wong-Baker FACES Pain Rating Scale(WBS) is a widely used pain assessment tool in Taiwan to help individuals communicate the intensity of their pain. However, in clinical practice, even when using various assessment tools to evaluate pain, Numeric Rating Scale-11 (NRS-11) is still commonly utilized to quantify the intensity of pain. The correlation between NRS and other pain assessment tools has not been extensively explored in Taiwan. Additionally, the influence of gender and education level on pain assessment among elderly individuals has not been extensively studied in Taiwan. The aim of this study is to investigate the correlation between pain assessment scales (NRS-11, VRS, WBS) in assessing pain intensity among elderly inpatients. The secondary objective of this study is to examine how gender and education level influence pain assessment among individuals, as well as to explore their preferences regarding pain assessment tools. Method: In this study, a questionnaire survey and purposive sampling were employed to recruit participants from a medical center located in central Taiwan. Participants were requested to assess their pain intensity in the past 24 hours using NRS-11, VRS, and WBS. Additionally, the study investigated their preferences for pain assessment tools. Result: A total of 252 participants were included in this study, with a mean age of 71.1 years (SD=6.2). Of these participants, 135 were male (53.6%), and 44.4% had a primary level or below education. Participants were asked to use NRS-11, VRS, and WBS to assess their current, maximum, and minimum pain intensity experienced in the past 24 hours. The findings indicated a significant correlation (p< .01) among all three pain assessment tools. No significant differences were observed in gender across the three pain assessment scales. For severe pain, there were significant differences in self-rated pain scales among the elderly participants with different education levels (F=3.08, p< .01; X²=17.25, X²=17.21, p< .01), but there were no significant differences observed for mild pain. Regarding preferences for pain assessment tools, 158 participants (62.7%) favored VRS, followed by WBS; gender and education level had no influence on their preferences. Conclusion: Most elderly participants prefer using VRS (Verbal Rating Scale) to self-reported their pain. The reason for this preference may be attributed to the verbal nature of VRS, as it is simple and easy to understand. Furthermore, it could be associated with the level of education among the elderly participants. The pain assessment using VRS demonstrated a significant correlation with NRS-11 and WBS, and gender was not found to have any influence on these assessment. Further research is needed to explore the effect of different education levels on self-reported pain intensity among elderly people in Taiwan.Keywords: pain assessment, elderly, gender, education
Procedia PDF Downloads 76574 Food Intake Pattern and Nutritional Status of Preschool Children of Chakma Ethnic Community
Authors: Md Monoarul Haque
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Nutritional status is a sensitive indicator of community health and nutrition among preschool children, especially the prevalence of undernutrition that affects all dimensions of human development and leads to growth faltering in early life. The present study is an attempt to assess the food intake pattern and nutritional status of pre-school Chakma tribe children. It was a cross-sectional community based study. The subjects were selected purposively. This study was conducted at Savar Upazilla of Rangamati. Rangamati is located in the Chittagong Division. Anthropometric data height and weight of the study subjects were collected by standard techniques. Nutritional status was measured using Z score according WHO classification. χ2 test, independent t-test, Pearson’s correlation, multiple regression and logistic regression was performed as P<0.05 level of significance. Statistical analyses were performed by appropriate univariate and multivariate techniques using SPSS windows 11.5. Moderate (-3SD to <-2SD) to severe underweight (<-3SD) were 23.8% and 76.2% study subjects had normal weight for their age. Moderate (-3SD to <-2SD) to severe (<-3SD) stunted children were only 25.6% and 74.4% children were normal and moderate to severe wasting were 14.7% whereas normal child was 85.3%. Significant association had been found between child nutritional status and monthly family income, mother education and occupation of father and mother. Age, sex and incomes of the family, education of mother and occupation of father were significantly associated with WAZ and HAZ of the study subjects (P=0.0001, P=0.025, P=0.001 and P=0.0001, P=0.003, P=0.031, P=0.092, P=0.008). Maximum study subjects took local small fish and some traditional tribal food like bashrool, jhijhipoka and pork very much popular food among tribal children. Energy, carbohydrate and fat intake was significantly associated with HAZ, WAZ, BAZ and MUACZ. This study demonstrates that malnutrition among tribal children in Bangladesh is much better than national scenario in Bangladesh. Significant association was found between child nutritional status and family monthly income, mother education and occupation of father and mother. Most of the study subjects took local small fish and some traditional tribal food. Significant association was also found between child nutritional status and dietary intake of energy, carbohydrate and fat.Keywords: food intake pattern, nutritional status, preschool children, Chakma ethnic community
Procedia PDF Downloads 506573 Efficacy of Single-Dose Azithromycin Therapy for the Treatment of Chlamydia trachomatis in Patients Evaluated for Child Sexual Abuse in an Urban Health Center 2006-16
Authors: Trenton Hubbard, Kenneth Soyemi, Emily Siffermann
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Introduction: According to the American Academy of Pediatrics (AAP) there are different weight-based recommendations for the treatment of Chlamydia trachomatis (CT) in patients who are being evaluated for sexual assault. Current AAP Red Book guidelines recommend that uncomplicated C. trachomatis anogenital infection in prepubertal patients weighing less than =<45 kg be treated with oral erythromycin 50 mg/kg/day QID for 14 days with no alternative therapies, and for patients whose weight => 45 kg are Azithromycin 1 gm PO once. Our study objective was to determine the efficacy of single-dose Azithromycin therapy for the treatment of Chlamydia trachomatis in patients weighing less than 50 kg who were evaluated for child sexual abuse in an urban setting. Methods: We conducted a retrospective chart review of historical medical records (paper and electronic) patients weighing less than 50 kg who were evaluated for child sexual abuse and subsequently treated for C. trachomatis infection with Azithromycin (20 mg/kg PO once up to a maximum 1 gm) and received a Test of Cure (TOC) from 2006-2016. Qualitative variables were expressed as percentages. Quantitative variables were expressed as mean values (+/- standard deviation [SD]) if they followed a normal distribution or as median values (interquartile range[IQR]) if they did not. Wilcoxson two-sample test was used to compare means of Azithromycin Dose, mg/kg, and TOC timing between treatment responders and non-responders. Results: We reviewed records of 34 patients, average age (SD) was 5.4 (2.0) years, 33 (97%) were treated for CT and 1(3%) for both GC and CT. 25 (74%) were females. Urine PCR was the most commonly used test at evaluation and as TOC with 13 (38%) patients completing both tests. The average (SD) dose of Azithromycin at treatment was 470 (136) mg and average (SD) mg/kg dose of 20 (1.9) mg/kg for all patients. Median (IQR) timing for TOC testing was 19 (14-26) days. Of the 33 with complete data 25 (74%) had a negative TOC. When compared with treatment non-responders (TOC failures), treatment responders received higher doses (average dose (SD) received 495 (139) vs 401(110), P 0.06)); similar average (SD) weight base dosing received (20.8(2.0) vs 19.7 (1.5), P 0.15)), and earlier average (SD)TOC test timing (18.8 (5.6) vs 32 (28.6) P 0.02)). Conclusion: Azithromycin dosing appears to be efficacious in the treatment of CT post sexual assault as majority of patients responded. Although treatment responders and non-responders received similar weight based doses, there is need for additional studies to understand variances and predictors of response.Keywords: child sexual abuse, chlmaydia trachmotis infection, single-dose azithromycin, weight less than or equal to 45 kilograms
Procedia PDF Downloads 294572 Oxidovanadium(IV) and Dioxidovanadium(V) Complexes: Efficient Catalyst for Peroxidase Mimetic Activity and Oxidation
Authors: Mannar R. Maurya, Bithika Sarkar, Fernando Avecilla
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Peroxidase activity is possibly successfully used for different industrial processes in medicine, chemical industry, food processing and agriculture. However, they bear some intrinsic drawback associated with denaturation by proteases, their special storage requisite and cost factor also. Now a day’s artificial enzyme mimics are becoming a research interest because of their significant applications over conventional organic enzymes for ease of their preparation, low price and good stability in activity and overcome the drawbacks of natural enzymes e.g serine proteases. At present, a large number of artificial enzymes have been synthesized by assimilating a catalytic center into a variety of schiff base complexes, ligand-anchoring, supramolecular complexes, hematin, porphyrin, nanoparticles to mimic natural enzymes. Although in recent years a several number of vanadium complexes have been reported by a continuing increase in interest in bioinorganic chemistry. To our best of knowledge, the investigation of artificial enzyme mimics of vanadium complexes is very less explored. Recently, our group has reported synthetic vanadium schiff base complexes capable of mimicking peroxidases. Herein, we have synthesized monoidovanadium(IV) and dioxidovanadium(V) complexes of pyrazoleone derivateis ( extensively studied on account of their broad range of pharmacological appication). All these complexes are characterized by various spectroscopic techniques like FT-IR, UV-Visible, NMR (1H, 13C and 51V), Elemental analysis, thermal studies and single crystal analysis. The peroxidase mimic activity has been studied towards oxidation of pyrogallol to purpurogallin with hydrogen peroxide at pH 7 followed by measuring kinetic parameters. The Michaelis-Menten behavior shows an excellent catalytic activity over its natural counterparts, e.g. V-HPO and HRP. The obtained kinetic parameters (Vmax, Kcat) were also compared with peroxidase and haloperoxidase enzymes making it a promising mimic of peroxidase catalyst. Also, the catalytic activity has been studied towards the oxidation of 1-phenylethanol in presence of H2O2 as an oxidant. Various parameters such as amount of catalyst and oxidant, reaction time, reaction temperature and solvent have been taken into consideration to get maximum oxidative products of 1-phenylethanol.Keywords: oxovanadium(IV)/dioxidovanadium(V) complexes, NMR spectroscopy, Crystal structure, peroxidase mimic activity towards oxidation of pyrogallol, Oxidation of 1-phenylethanol
Procedia PDF Downloads 343571 Study of Polychlorinated Dibenzo-P-Dioxins and Dibenzofurans Dispersion in the Environment of a Municipal Solid Waste Incinerator
Authors: Gómez R. Marta, Martín M. Jesús María
Abstract:
The general aim of this paper identifies the areas of highest concentration of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) around the incinerator through the use of dispersion models. Atmospheric dispersion models are useful tools for estimating and prevent the impact of emissions from a particular source in air quality. These models allow considering different factors that influence in air pollution: source characteristics, the topography of the receiving environment and weather conditions to predict the pollutants concentration. The PCDD/Fs, after its emission into the atmosphere, are deposited on water or land, near or far from emission source depending on the size of the associated particles and climatology. In this way, they are transferred and mobilized through environmental compartments. The modelling of PCDD/Fs was carried out with following tools: Atmospheric Dispersion Model Software (ADMS) and Surfer. ADMS is a dispersion model Gaussian plume, used to model the impact of air quality industrial facilities. And Surfer is a program of surfaces which is used to represent the dispersion of pollutants on a map. For the modelling of emissions, ADMS software requires the following input parameters: characterization of emission sources (source type, height, diameter, the temperature of the release, flow rate, etc.) meteorological and topographical data (coordinate system), mainly. The study area was set at 5 Km around the incinerator and the first population center nearest to focus PCDD/Fs emission is about 2.5 Km, approximately. Data were collected during one year (2013) both PCDD/Fs emissions of the incinerator as meteorology in the study area. The study has been carried out during period's average that legislation establishes, that is to say, the output parameters are taking into account the current legislation. Once all data required by software ADMS, described previously, are entered, and in order to make the representation of the spatial distribution of PCDD/Fs concentration and the areas affecting them, the modelling was proceeded. In general, the dispersion plume is in the direction of the predominant winds (Southwest and Northeast). Total levels of PCDD/Fs usually found in air samples, are from <2 pg/m3 for remote rural areas, from 2-15 pg/m3 in urban areas and from 15-200 pg/m3 for areas near to important sources, as can be an incinerator. The results of dispersion maps show that maximum concentrations are the order of 10-8 ng/m3, well below the values considered for areas close to an incinerator, as in this case.Keywords: atmospheric dispersion, dioxin, furan, incinerator
Procedia PDF Downloads 217