Search results for: level set method
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 28403

Search results for: level set method

4523 An Appraisal of Mining Sector Corporate Social Responsibility Processes in Mhondoro-Ngezi, Zimbabwe

Authors: A. T. Muruviwa

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To-date, the discourse on corporate social responsibility (CSR) has primarily centred on the actions and inactions of corporations; hence, the dominant focus on CSR has been on impacts and outcomes. The obscuring effect of this approach has, arguably, resulted in the emergence of what may be termed a ‘Northern’ agenda on CSR theory and practice, in contrast to an emergency ‘Southern’ discourse, which appears to highlight the crucial issues of poverty reduction, infrastructure development and the broader questions of social provisioning and community empowerment. Some scholars have explicitly called for a CSR research agenda that focuses on the 'reciprocal duties' of the stakeholders in the CSR process rather than fixate on the actions and inactions of business. It is against the backdrop of these contestations that this study assesses the reciprocal relationships amongst CSR stakeholders in a Zimbabwean platinum mining town, with a view to demonstrating how such relationships – and the expectations and obligations embedded in them – impact on the success or failure of CSR initiatives. The existence of mutual relations between the corporation and its stakeholders signifies the successes of CSR processes and hence the outcomes. The company is Zimplats Mining Company; the community is Mhondoro-Ngezi, and the stakeholders are clearly identified in the study. The study utilised a triangulated design, with data collected using a mini survey, focus groups, in-depth interview and observation. The key findings are that the CSR process in the study community is dominated by the mining company. Despite the existence of a CSR framework that recognises government, local leaders and community members as legitimate stakeholders, there is little evidence of concrete contributions made by these stakeholders towards the realisation of CSR objectives. As a result, the community development process – in so far as CSR is concerned – fails to address the developmental concerns of the various stakeholders. On the basis of these findings, the study concludes that there is a crisis of reciprocity in the CSR process in Mhondoro-Ngezi, and that a situation where the conceptualisation of local development needs and the deployment of specific development tools seems to be driven by one stakeholder almost to the exclusion of all others, can only present contradictory development outcomes. The significance of this study is that it allows for the development of a more nuanced and robust CSR discourse. Rather than focusing on the corporate and stakeholder perspectives and outcomes of CSR initiatives, this study examines the CSR- development nexus by interrogating the idea of reciprocal responsibility as a sin qua non to CSR success. This analytical strategy and focus allow the researcher to gain a clear understanding of how stakeholder relationships and duties influence CSR processes and also the overall outcome. At a more practical level, the findings of the study should help to shape the policy on corporate community relationships with a view to enhancing the role of mining in development.

Keywords: community development, processes, reciprocity, stakeholders

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4522 Greenhouse Gasses’ Effect on Atmospheric Temperature Increase and the Observable Effects on Ecosystems

Authors: Alexander J. Severinsky

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Radiative forces of greenhouse gases (GHG) increase the temperature of the Earth's surface, more on land, and less in oceans, due to their thermal capacities. Given this inertia, the temperature increase is delayed over time. Air temperature, however, is not delayed as air thermal capacity is much lower. In this study, through analysis and synthesis of multidisciplinary science and data, an estimate of atmospheric temperature increase is made. Then, this estimate is used to shed light on current observations of ice and snow loss, desertification and forest fires, and increased extreme air disturbances. The reason for this inquiry is due to the author’s skepticism that current changes cannot be explained by a "~1 oC" global average surface temperature rise within the last 50-60 years. The only other plausible cause to explore for understanding is that of atmospheric temperature rise. The study utilizes an analysis of air temperature rise from three different scientific disciplines: thermodynamics, climate science experiments, and climactic historical studies. The results coming from these diverse disciplines are nearly the same, within ± 1.6%. The direct radiative force of GHGs with a high level of scientific understanding is near 4.7 W/m2 on average over the Earth’s entire surface in 2018, as compared to one in pre-Industrial time in the mid-1700s. The additional radiative force of fast feedbacks coming from various forms of water gives approximately an additional ~15 W/m2. In 2018, these radiative forces heated the atmosphere by approximately 5.1 oC, which will create a thermal equilibrium average ground surface temperature increase of 4.6 oC to 4.8 oC by the end of this century. After 2018, the temperature will continue to rise without any additional increases in the concentration of the GHGs, primarily of carbon dioxide and methane. These findings of the radiative force of GHGs in 2018 were applied to estimates of effects on major Earth ecosystems. This additional force of nearly 20 W/m2 causes an increase in ice melting by an additional rate of over 90 cm/year, green leaves temperature increase by nearly 5 oC, and a work energy increase of air by approximately 40 Joules/mole. This explains the observed high rates of ice melting at all altitudes and latitudes, the spread of deserts and increases in forest fires, as well as increased energy of tornadoes, typhoons, hurricanes, and extreme weather, much more plausibly than the 1.5 oC increase in average global surface temperature in the same time interval. Planned mitigation and adaptation measures might prove to be much more effective when directed toward the reduction of existing GHGs in the atmosphere.

Keywords: greenhouse radiative force, greenhouse air temperature, greenhouse thermodynamics, greenhouse historical, greenhouse radiative force on ice, greenhouse radiative force on plants, greenhouse radiative force in air

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4521 Cycling Usage and Determinants on University Campus in Ghana: The Case of Kwame Nkrumah University of Science and Technology

Authors: Nicholas Anarfi Bofah, James Damsere- Derry

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There is increasing interest among institutions, governments, and international organisations to combat congestion, reduce contribution to green gases and provide sustainable urban transportation. College campuses are a preeminent setting for promoting active commuting to ameliorate a community's healthy lifestyle. Cycling is an important physical activity and has a long-term effect on health, and it is considered one of the top five interventions to reduce the prevalence of non-communicable diseases. The main objectives of the research were: (i) to identify students’ attitudes and behavior toward cycling usage, (ii) to identify barriers and opportunities for cycling on a university campus, and (iii) to construct tangible policy recommendations for promoting cycling in the vicinity of the university. The data used in this study were obtained from a survey conducted among students at the Kwame Nkrumah University of Science and Technology (KNUST) in Kumasi between May 2022 and September 2022. A convenient sampling method was used to recruit and interview 398 participants. Two survey assistants who are former students of the university were engaged to administer the questionnaires randomly to students at the selected locations. Descriptive statistics were employed in the analysis of the data. Out of the 398 questionnaires, bicycle ridership and ownership among university students were 57% and 39%, respectively. Generally, the desire to use a bicycle as a mode of transport on campus was 36%. The desire to use a bicycle on campus was more prevalent among males 41% compared to females 30%. There is a high potential for increasing bicycle use among students. Recommendations include the provision of bicycle lanes, public education on the use of bicycles, and a campus bicycle-sharing program.

Keywords: sustainable development, cycling, university campus, bicycle

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4520 Emergency Management of Poisoning Tracery Care Hospital in India

Authors: Rajiv Ratan Singh, Sachin Kumar Tripathi, Pradeep Kumar Yadav

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The timely evaluation, diagnosis, and treatment of people who have been exposed to toxic chemicals is a crucial component of emergency poison management in the medical field. The various substances that can poison include chemicals, medications, and naturally occurring poisons. The toxicology of the particular drug involved, as well as the symptoms and indicators of poisoning, must be thoroughly understood to handle poisoning emergencies effectively. One of the most important aspects of emergency poison management in medicine is the prompt examination, diagnosis, and treatment of persons who have been exposed to dangerous substances. To properly manage poisoning crises, one must have a good understanding of the toxicology of the particular medication concerned, as well as the signs and indicators of poisoning. Emergency management of poisoning includes not only prompt medical attention but also patient education, follow-up care, and monitoring for any long-term consequences. To achieve the greatest results for patients, the management of poisoning is a complicated and dynamic process that calls for collaboration between medical professionals, first responders, and toxicologists. All poisoned patients who present to the emergency room are assessed and diagnosed based on a collection of symptoms and a biochemical diagnosis, and they are then provided targeted, specialized treatment for the toxin identified. This article focuses on the loxodromic strategy as the primary method of treatment for poisoned patients. The authors of this article conclude that mortality and morbidity can be reduced if patients visit the emergency room promptly and receive targeted treatment.

Keywords: antidotes, blood poisoning, emergency medicine, gastric lavage, medico-legal aspects, patient care

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4519 Visual Outcome After 360-Degree Retinectomy in Total Rhegmatogenous Retinal Detachment with Advanced Proliferative Vitreoretinopathy: A Case Series

Authors: Andriati Nadhilah Widyarini, Ezra Margareth

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Introduction: Rhegmatogenous retinal detachment is a condition where there’s a break in the retina, which allows the vitreous to directly enter the subretinal space. Proliferative vitreoretinopathy (PVR) may develop due to this condition and can result in a new break, which could cause traction on the previously detached retina. Various methods of therapy can be done to treat this complication. Case: This case series involved 2 eyes of 2 patients who had total retinal detachment with advanced PVR. Pars plana vitrectomy was performed, and a 360-degree retinectomy procedure with perfluorocarbon liquid usage was done. This was followed by endo laser retinopexy to surround the border of retinectomy. 5000 cs silicone oil was used in 1 eye, whereas 12% of perfluoropropane gas was used in the other eye as a tamponade. These procedures were performed with meticulous attention to prevent any fluid from entering the subretinal space. Postoperative examination showed attachment of the retina and improvement of the patient’s visual acuity. Both eyes’ intraocular pressure was in the normal range. One eye developed retinal displacement, but no other complications occurred. Discussion: Rhegmatogenous retinal detachment with advanced PVR is a complex situation for vitreoretinal surgeons. PVR is characterized by the growth and migration of preretinal or subretinal membranes. PVR is the most common cause of retinal reattachment failure. A 360-degree retinectomy is an alternative surgical method to overcome this condition. Objectives of this procedure are releasing retinal traction caused by PVR, reducing the recurrence rate of PVR, and reattaching the retina to the pigment epithelial surface. Conclusion: 360-degree retinectomy provides satisfactory retinal reattachment and visual outcome improvement in rhegmatogenous retinal detachment with advanced PVR.

Keywords: RRD, retinectomy, pars plana, advanced PVR

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4518 Evaluating the Validity of CFD Model of Dispersion in a Complex Urban Geometry Using Two Sets of Experimental Measurements

Authors: Mohammad R. Kavian Nezhad, Carlos F. Lange, Brian A. Fleck

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This research presents the validation study of a computational fluid dynamics (CFD) model developed to simulate the scalar dispersion emitted from rooftop sources around the buildings at the University of Alberta North Campus. The ANSYS CFX code was used to perform the numerical simulation of the wind regime and pollutant dispersion by solving the 3D steady Reynolds-averaged Navier-Stokes (RANS) equations on a building-scale high-resolution grid. The validation study was performed in two steps. First, the CFD model performance in 24 cases (eight wind directions and three wind speeds) was evaluated by comparing the predicted flow fields with the available data from the previous measurement campaign designed at the North Campus, using the standard deviation method (SDM), while the estimated results of the numerical model showed maximum average percent errors of approximately 53% and 37% for wind incidents from the North and Northwest, respectively. Good agreement with the measurements was observed for the other six directions, with an average error of less than 30%. In the second step, the reliability of the implemented turbulence model, numerical algorithm, modeling techniques, and the grid generation scheme was further evaluated using the Mock Urban Setting Test (MUST) dispersion dataset. Different statistical measures, including the fractional bias (FB), the geometric mean bias (MG), and the normalized mean square error (NMSE), were used to assess the accuracy of the predicted dispersion field. Our CFD results are in very good agreement with the field measurements.

Keywords: CFD, plume dispersion, complex urban geometry, validation study, wind flow

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4517 Expanding the Atelier: Design Lead Academic Project Using Immersive User-Generated Mobile Images and Augmented Reality

Authors: David Sinfield, Thomas Cochrane, Marcos Steagall

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While there is much hype around the potential and development of mobile virtual reality (VR), the two key critical success factors are the ease of user experience and the development of a simple user-generated content ecosystem. Educational technology history is littered with the debris of over-hyped revolutionary new technologies that failed to gain mainstream adoption or were quickly superseded. Examples include 3D television, interactive CDROMs, Second Life, and Google Glasses. However, we argue that this is the result of curriculum design that substitutes new technologies into pre-existing pedagogical strategies that are focused upon teacher-delivered content rather than exploring new pedagogical strategies that enable student-determined learning or heutagogy. Visual Communication design based learning such as Graphic Design, Illustration, Photography and Design process is heavily based on the traditional forms of the classroom environment whereby student interaction takes place both at peer level and indeed teacher based feedback. In doing so, this makes for a healthy creative learning environment, but does raise other issue in terms of student to teacher learning ratios and reduced contact time. Such issues arise when students are away from the classroom and cannot interact with their peers and teachers and thus we see a decline in creative work from the student. Using AR and VR as a means of stimulating the students and to think beyond the limitation of the studio based classroom this paper will discuss the outcomes of a student project considering the virtual classroom and the techniques involved. The Atelier learning environment is especially suited to the Visual Communication model as it deals with the creative processing of ideas that needs to be shared in a collaborative manner. This has proven to have been a successful model over the years, in the traditional form of design education, but has more recently seen a shift in thinking as we move into a more digital model of learning and indeed away from the classical classroom structure. This study focuses on the outcomes of a student design project that employed Augmented Reality and Virtual Reality technologies in order to expand the dimensions of the classroom beyond its physical limits. Augmented Reality when integrated into the learning experience can improve the learning motivation and engagement of students. This paper will outline some of the processes used and the findings from the semester-long project that took place.

Keywords: augmented reality, blogging, design in community, enhanced learning and teaching, graphic design, new technologies, virtual reality, visual communications

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4516 Review of Capitalization of Construction Industry on Sustainable Risk Management in Nigeria

Authors: Nnadi Ezekiel Ejiofor

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The construction industry plays a decisive role in the healthy development of any nation. Not only large but even small construction projects contribute to a country’s economic growth. There is a need for good management to ensure successful delivery and sustainability because of the plethora of risks that have resulted in low-profit margins for contractors, cost and schedule overruns, poor quality delivery, and abandoned projects. This research reviewed Capitalization on Sustainable Risk Management. Questionnaires and oral interviews conducted were utilized as means of data collection. One hundred and ninety-eight (198) large construction firms in Nigeria form the population of this study. 15 (fifteen) companies that emanated from merger and acquisition were used for the study. The instruments used for data collection were a researcher-developed structured questionnaire based on a five-point rating scale, interviews, focus group discussion, and secondary sources (bill of quantities and stock and exchange commission). The instrument was validated by two experts in the field. The reliability of the instrument was established by applying the split-half method. Kendall’s coefficient of concordance was used to test the data, and a degree of agreement was obtained. Data were subjected to descriptive statistics and analyzed using analysis of variance, t-test, and SPSS. The identified impacts of capitalization were an increase in turnover (24.5%), improvement in the image (24.5%), risk reduction (20%), business expansion (17.3%), and geographical spread (13.6%). The study strongly advocates the inclusion of risk management evaluation as part of the construction procurement process.

Keywords: capitalization, project delivery, risks, risk management, sustainability

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4515 Preparation and In vitro Characterization of Nanoparticle Hydrogel for Wound Healing

Authors: Rajni Kant Panik

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The aim of the present study was to develop and evaluate mupirocin loaded nanoparticle incorporated into hydrogel as an infected wound healer. Incorporated Nanoparticle in hydrogel provides a barrier that effectively prevents the contamination of the wound and further progression of infection to deeper tissues. Hydrogel creates moist healing environment on wound space with good fluid absorbance. Nanoparticles were prepared by double emulsion solvent evaporation method using different ratios of PLGA polymer and the hydrogels was developed using sodium alginate and gelatin. Further prepared nanoparticles were then incorporated into the hydrogels. The formulations were characterized by FT-IR and DSC for drug and polymer compatibility and surface morphology was studied by TEM. Nanoparticle hydrogel were evaluated for their size, shape, encapsulation efficiency and for in vitro studies. The FT-IR and DSC confirmed the absence of any drug polymer interaction. The average size of Nanoparticle was found to be in range of 208.21-412.33 nm and shape was found to be spherical. The maximum encapsulation efficiency was found to be 69.03%. The in vitro release profile of Nanoparticle incorporated hydrogel formulation was found to give sustained release of drug. Antimicrobial activity testing confirmed that encapsulated drug preserve its effectiveness. The stability study confirmed that the formulation prepared were stable. Present study complements our finding that mupirocin loaded Nanoparticle incorporated into hydrogel has the potential to be an effective and safe novel addition for the release of mupirocin in sustained manner, which may be a better option for the management of wound. These finding also supports the progression of antibiotic via hydrogel delivery system is a novel topical dosage form for the management of wound.

Keywords: hydrogel, nanoparticle, PLGA, wound healing

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4514 Impact of Silicon Surface Modification on the Catalytic Performance Towards CO₂ Conversion of Cu₂S/Si-Based Photocathodes

Authors: Karima Benfadel, Lamia Talbi, Sabiha Anas Boussaa, Afaf Brik, Assia Boukezzata, Yahia Ouadah, Samira Kaci

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In order to prevent global warming, which is mainly caused by the increase in carbon dioxide levels in the atmosphere, it is interesting to produce renewable energy in the form of chemical energy by converting carbon dioxide into alternative fuels and other energy-dense products. Photoelectrochemical reduction of carbon dioxide to value-added products and fuels is a promising and current method. The objective of our study is to develop Cu₂S-based photoélectrodes, in which Cu₂S is used as a CO₂ photoelectrocatalyst deposited on nanostructured silicon substrates. Cu₂S thin layers were deposited using the chemical bath deposition (CBD) technique. Silicon nanowires and nanopyramids were obtained by alkaline etching. SEM and UV-visible spectroscopy was used to analyse the morphology and optical characteristics. By using a potentiostat station, we characterized the photoelectrochemical properties. We performed cyclic voltammetry in the presence and without CO₂ purging as well as linear voltammetry (LSV) in the dark and under white light irradiation. We perform chronoamperometry to study the stability of our photocathodes. The quality of the nanowires and nanopyramids was visible in the SEM images, and after Cu₂S deposition, we could see how the deposition was distributed over the textured surfaces. The inclusion of the Cu₂S layer applied on textured substrates significantly reduces the reflectance (R%). The catalytic performance towards CO₂ conversion of Cu₂S/Si-based photocathodes revealed that the texturing of the silicon surface with nanowires and pyramids has a better photoelectrochemical behavior than those without surface modifications.

Keywords: CO₂ conversion, Cu₂S photocathode, silicone nanostructured, electrochemistry

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4513 Growth Performance and Intestinal Morphology of Isa Brown Pullet Chicks Fed Diets Containing Turmeric and Clove

Authors: Ayoola Doris Ayodele, Grace Oluwatoyin Tayo, Martha Dupe Olumide, Opeyemi Arinola Ajayi, Ayodeji Taofeek Ayo-Bello

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Antibiotics have been widely used in animal nutrition to improve growth performance and health worldwide for many decades. However, there are rising concerns on the negative impact of dependence on antibiotic growth promoters (AGP) to improve animal performance despite its tremendous use. The need to improve performance in poultry production creates demand for natural alternative sources. Phytogenic feed additives (PFA) are plant-derived natural bioactive compounds that could be incorporated into animal feed to enhance livestock productivity. The effect of Turmeric, clove and turmeric + clove as feed additive was evaluated on performance and intestinal morphology of egg type chickens. 504- fifteen day old Isa brown chicks were weighed and randomly distributed to nine dietary treatments by a 3 x 3 factorial arrangement (test ingredient x inclusion level) in a completely randomized design, with four replicates of 14 birds each. The birds were fed Chick starter diet containing (2800 kcal/kg ME; 20.8% CP). Dietary treatments were Group 1 (T1- basal diet with 0% Turmeric inclusion), (T2- basal diet with 1% Turmeric inclusion), (T3- basal diet with 2% Turmeric inclusion). Group 2 (T4- basal diet with 0% clove inclusion), (T5- basal diet with 1% clove inclusion), (T6- basal diet with 2% clove inclusion). Group 3, turmeric + clove combination on 1:1 ratio weight for weight (T7- basal diet with 0% turmeric + 0% clove inclusion), (T8- basal diet with 0.5% turmeric + 0.5 clove% inclusion), (T9- basal diet with 1% turmeric + 1% clove inclusion). Performance parameters were evaluated throughout the experiment. The experiment spanned from day 15 to 56. Data were analyzed using Analysis of Variance (ANOVA) followed by Duncan’s Multiple Range Test with significance of P≤ 0.05. Significant differences (P>0.05) were not observed in final body weight, weight gain, feed intake and FCR among birds fed with diets containing across the treatments. However, birds fed with test ingredients showed higher numerical values in final body weight and weight gain when compared to the birds without additive. Birds on T8 had the highest final body weight value of 617.33 g and low values in all the control treatments (T1 -588 g, T4- 572 g and T7 -584 g). At day 56, intestinal samples were taken from the jejunum and ileum to evaluate the villus height, crypt depth and villus: crypt depth ratio. Addition of turmeric, clove and turmeric + clove in the diet produced significant (P< 0.05) effect on Jejunum and ileum of birds. Therefore, Turmeric and clove can be used as feed additives for pullet birds because they have a positive effect on growth performance and intestinal morphology of pullet chicks.

Keywords: clove, intestinal morphology, isa brown chicks, performance, turmeric

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4512 Spatiotemporal Variation Characteristics of Soil pH around the Balikesir City, Turkey

Authors: Çağan Alevkayali, Şermin Tağil

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Determination of soil pH surface distribution in urban areas is substantial for sustainable development. Changes on soil properties occur due to functions on performed in agriculture, industry and other urban functions. Soil pH is important to effect on soil productivity which based on sensitive and complex relation between plant and soil. Furthermore, the spatial variability of soil reaction is necessary to measure the effects of urbanization. The objective of this study was to explore the spatial variation of soil pH quality and the influence factors of human land use on soil Ph around Balikesir City using data for 2015 and Geographic Information Systems (GIS). For this, soil samples were taken from 40 different locations, and collected with the method of "Systematic Random" from the pits at 0-20 cm depths, because anthropologic sourced pollutants accumulate on upper layers of soil. The study area was divided into a grid system with 750 x 750 m. GPS was used to determine sampling locations, and Inverse Distance Weighting (IDW) interpolation technique was used to analyze the spatial distribution of pH in the study area and to predict the variable values of un-exampled places with the help from the values of exampled places. Natural soil acidity and alkalinity depend on interaction between climate, vegetation, and soil geological properties. However, analyzing soil pH is important to indirectly evaluate soil pollution caused by urbanization and industrialization. The result of this study showed that soil pH around the Balikesir City was neutral, in generally, with values were between 6.5 and 7.0. On the other hand, some slight changes were demonstrated around open dump areas and the small industrial sites. The results obtained from this study can be indicator of important soil problems and this data can be used by ecologists, planners and managers to protect soil supplies around the Balikesir City.

Keywords: Balikesir, IDW, GIS, spatial variability, soil pH, urbanization

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4511 Quantifying Temporal Variation of Volatile Organic Compounds and Their Ozone Forming Potential at Rural Atmosphere in Delhi

Authors: Amit Kumar, Bhupendra Pratap Singh, Manoj Singh, Monika Punia, Krishan Kumar, V. K. Jain

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Ambient concentrations of volatile organic compounds (VOCs) were investigated in order to find out temporal variations and their ozone forming potentials (OFP) at rural site in Delhi National Capital Region during summer 2013. Sampling was performed for continuous five days, to identify the differences in working days and weekend VOCs concentration levels. Sampling and analytical procedure for VOCs were done using National Institute for Occupational Safety and Health (NIOSH) standard method. On each sampling day, VOCs samples were collected for 3-hours in the morning, afternoon and evening. There has been observed a noticeable contrast in the concentration of VOCs levels between working days and weekend. However, most of the VOCs showed diurnal fluctuations with higher concentrations in the morning and evening as compared to afternoon which might be due to change in meteorology. The results showed that mean toluene/benzene and m-/p-xylene/benzene ratios were higher in the afternoon while it was lower during morning and evening. The relative contribution of the VOCs to ozone formation, total propylene equivalent concentrations and OFP were calculated. Toluene was the most contributing organic contaminant to ozone formation as well as ambient VOCs concentrations. Results obtained in current study demonstrate that ozone formation at rural site in Delhi is probably limited by the emissions of VOCs.

Keywords: VOCs, rural, NIOSH, ozone forming potential, propylene equivalent concentration

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4510 Preparation of Magnetic Hydroxyapatite Composite by Wet Chemical Process for Phycobiliproteins Adsorption

Authors: Shu-Jen Chen, Yi-Chien Wan, Ruey-Chi Wang

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Hydroxyapatite (Ca10(PO4)6(OH)2, HAp) can be applied to the fabrication of bone replacement materials, the composite of dental filling, and the adsorption of biomolecules and dyes. The integration of HAp and magnetic materials would offer several advantages for bio-separation process because the magnetic adsorbents is capable of recovered by applied magnetic field. C-phycocyanin (C-PC) and Allophycocyanin (APC), isolated from Spirulina platensis, can be used in fluorescent labeling probes, health care foods and clinical diagnostic reagents. Although the purification of C-PC and APC are reported by HAp adsorption, the adsorption of C-PC and APC by magnetic HAp composites was not reported yet. Therefore, the fabrication of HAp with magnetic silica nanoparticles for proteins adsorption was investigated in this work. First, the magnetic silica particles were prepared by covering silica layer on Fe3O4 nanoparticles with a reverse micelle method. Then, the Fe3O4@SiO2 nanoparticles were mixed with calcium carbonate to obtain magnetic silica/calcium carbonate composites (Fe3O4@SiO2/CaCO3). The Fe3O4@SiO2/CaCO3 was further reacted with K2HPO4 for preparing the magnetic silica/hydroxyapatite composites (Fe3O4@SiO2/HAp). The adsorption experiments indicated that the adsorption capacity of Fe3O4@SiO2/HAp toward C-PC and APC were highest at pH 6. The adsorption of C-PC and APC by Fe3O4@SiO2/HAp could be correlated by the pseudo-second-order model, indicating chemical adsorption dominating the adsorption process. Furthermore, the adsorption data showed that the adsorption of Fe3O4@SiO2/HAp toward C-PC and APC followed the Langmuir isotherm. The isoelectric points of C-PC and APC were around 5.0. Additionally, the zeta potential data showed the Fe3O4@SiO2/HAp composite was negative charged at pH 6. Accordingly, the adsorption mechanism of Fe3O4@SiO2/HAp toward C-PC and APC should be governed by hydrogen bonding rather than electrostatic interaction. On the other hand, as compared to C-PC, the Fe3O4@SiO2/HAp shows higher adsorption affinity toward APC. Although the Fe3O4@SiO2/HAp cannot recover C-PC and APC from Spirulina platensis homogenate, the Fe3O4@SiO2/HAp can be applied to separate C-PC and APC.

Keywords: hydroxyapatite, magnetic, C-phycocyanin, allophycocyanin

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4509 The Utilization of Tea Extract within the Realm of the Food Industry

Authors: Raana Babadi Fathipour

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Tea, a beverage widely cherished across the globe, has captured the interest of scholars with its recent acknowledgement for possessing noteworthy health advantages. Of particular significance is its proven ability to ward off ailments such as cancer and cardiovascular afflictions. Moreover, within the realm of culinary creations, lipid oxidation poses a significant challenge for food product development. In light of these aforementioned concerns, this present discourse turns its attention towards exploring diverse methodologies employed in extracting polyphenols from various types of tea leaves and examining their utility within the vast landscape of the ever-evolving food industry. Based on the discoveries unearthed in this comprehensive investigation, it has been determined that the fundamental constituents of tea are polyphenols possessed of intrinsic health-enhancing properties. This includes an assortment of catechins, namely epicatechin, epigallocatechin, epicatechin gallate, and epigallocatechin gallate. Moreover, gallic acid, flavonoids, flavonols and theaphlavins have also been detected within this aromatic beverage. Of these myriad components examined vigorously in this study's analysis, catechin emerges as particularly beneficial. Multiple techniques have emerged over time to successfully extract key compounds from tea plants, including solvent-based extraction methodologies, microwave-assisted water extraction approaches and ultrasound-assisted extraction techniques. In particular, consideration is given to microwave-assisted water extraction method as a viable scheme which effectively procures valuable polyphenols from tea extracts. This methodology appears adaptable for implementation within sectors such as dairy production along with meat and oil industries alike.

Keywords: camellia sinensis, extraction, food application, shelf life, tea

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4508 Efficacy of Biofeedback-Assisted Pelvic Floor Muscle Training on Postoperative Stress Urinary Incontinence

Authors: Asmaa M. El-Bandrawy, Afaf M. Botla, Ghada E. El-Refaye, Hassan O. Ghareeb

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Background: Urinary incontinence is a common problem among adults. Its incidence increases with age and it is more frequent in women. Pelvic floor muscle training (PFMT) is the first-line therapy in the treatment of pelvic floor dysfunction (PFD) either alone or combined with biofeedback-assisted PFMT. The aim of the work: The purpose of this study is to evaluate the efficacy of biofeedback-assisted PFMT in postoperative stress urinary incontinence. Settings and Design: A single blind controlled trial design was. Methods and Material: This study was carried out in 30 volunteer patients diagnosed as severe degree of stress urinary incontinence and they were admitted to surgical treatment. They were divided randomly into two equal groups: (Group A) consisted of 15 patients who had been treated with post-operative biofeedback-assisted PFMT and home exercise program (Group B) consisted of 15 patients who had been treated with home exercise program only. Assessment of all patients in both groups (A) and (B) was carried out before and after the treatment program by measuring intra-vaginal pressure in addition to the visual analog scale. Results: At the end of the treatment program, there was a highly statistically significant difference between group (A) and group (B) in the intra-vaginal pressure and the visual analog scale favoring the group (A). Conclusion: biofeedback-assisted PFMT is an effective method for the symptomatic relief of post-operative female stress urinary incontinence.

Keywords: stress urinary incontinence, pelvic floor muscles, pelvic floor exercises, biofeedback

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4507 Application of Principal Component Analysis and Ordered Logit Model in Diabetic Kidney Disease Progression in People with Type 2 Diabetes

Authors: Mequanent Wale Mekonen, Edoardo Otranto, Angela Alibrandi

Abstract:

Diabetic kidney disease is one of the main microvascular complications caused by diabetes. Several clinical and biochemical variables are reported to be associated with diabetic kidney disease in people with type 2 diabetes. However, their interrelations could distort the effect estimation of these variables for the disease's progression. The objective of the study is to determine how the biochemical and clinical variables in people with type 2 diabetes are interrelated with each other and their effects on kidney disease progression through advanced statistical methods. First, principal component analysis was used to explore how the biochemical and clinical variables intercorrelate with each other, which helped us reduce a set of correlated biochemical variables to a smaller number of uncorrelated variables. Then, ordered logit regression models (cumulative, stage, and adjacent) were employed to assess the effect of biochemical and clinical variables on the order-level response variable (progression of kidney function) by considering the proportionality assumption for more robust effect estimation. This retrospective cross-sectional study retrieved data from a type 2 diabetic cohort in a polyclinic hospital at the University of Messina, Italy. The principal component analysis yielded three uncorrelated components. These are principal component 1, with negative loading of glycosylated haemoglobin, glycemia, and creatinine; principal component 2, with negative loading of total cholesterol and low-density lipoprotein; and principal component 3, with negative loading of high-density lipoprotein and a positive load of triglycerides. The ordered logit models (cumulative, stage, and adjacent) showed that the first component (glycosylated haemoglobin, glycemia, and creatinine) had a significant effect on the progression of kidney disease. For instance, the cumulative odds model indicated that the first principal component (linear combination of glycosylated haemoglobin, glycemia, and creatinine) had a strong and significant effect on the progression of kidney disease, with an effect or odds ratio of 0.423 (P value = 0.000). However, this effect was inconsistent across levels of kidney disease because the first principal component did not meet the proportionality assumption. To address the proportionality problem and provide robust effect estimates, alternative ordered logit models, such as the partial cumulative odds model, the partial adjacent category model, and the partial continuation ratio model, were used. These models suggested that clinical variables such as age, sex, body mass index, medication (metformin), and biochemical variables such as glycosylated haemoglobin, glycemia, and creatinine have a significant effect on the progression of kidney disease.

Keywords: diabetic kidney disease, ordered logit model, principal component analysis, type 2 diabetes

Procedia PDF Downloads 13
4506 Data Quality and Associated Factors on Regular Immunization Programme at Ararso District: Somali Region- Ethiopia

Authors: Eyob Seife, Molla Alemayaehu, Tesfalem Teshome, Bereket Seyoum, Behailu Getachew

Abstract:

Globally, immunization averts between 2 and 3 million deaths yearly, but Vaccine-Preventable Diseases still account for more in Sub-Saharan African countries and takes the majority of under-five deaths yearly, which indicates the need for consistent and on-time information to have evidence-based decision so as to save lives of these vulnerable groups. However, ensuring data of sufficient quality and promoting an information-use culture at the point of collection remains critical and challenging, especially in remote areas where the Ararso district is selected based on a hypothesis of there is a difference in reported and recounted immunization data consistency. Data quality is dependent on different factors where organizational, behavioral, technical and contextual factors are the mentioned ones. A cross-sectional quantitative study was conducted on September 2022 in the Ararso district. The study used the world health organization (WHO) recommended data quality self-assessment (DQS) tools. Immunization tally sheets, registers and reporting documents were reviewed at 4 health facilities (1 health center and 3 health posts) of primary health care units for one fiscal year (12 months) to determine the accuracy ratio, availability and timeliness of reports. The data was collected by trained DQS assessors to explore the quality of monitoring systems at health posts, health centers, and at the district health office. A quality index (QI), availability and timeliness of reports were assessed. Accuracy ratios formulated were: the first and third doses of pentavalent vaccines, fully immunized (FI), TT2+ and the first dose of measles-containing vaccines (MCV). In this study, facility-level results showed poor timeliness at all levels and both over-reporting and under-reporting were observed at all levels when computing the accuracy ratio of registration to health post reports found at health centers for almost all antigens verified. A quality index (QI) of all facilities also showed poor results. Most of the verified immunization data accuracy ratios were found to be relatively better than that of quality index and timeliness of reports. So attention should be given to improving the capacity of staff, timeliness of reports and quality of monitoring system components, namely recording, reporting, archiving, data analysis and using information for decisions at all levels, especially in remote and areas.

Keywords: accuracy ratio, ararso district, quality of monitoring system, regular immunization program, timeliness of reports, Somali region-Ethiopia

Procedia PDF Downloads 47
4505 Investigating the Characteristics of Multi-Plastic Composites Prepared from a Mixture of Silk Fibers and Recycled Polycarbonate

Authors: Razieh Shamsi, Mehdi Faezipour, Ali Abdolkhani

Abstract:

In this research, the characteristics of composites prepared from waste silk fibers and recycled polycarbonate polymer (used compacted boards) at four levels of 0, 10, 20, and 30% (silk fibers) and using 2% N- 2-Aminoethyl-3-Aminopropyltrimethoxysilane was investigated as a coupling agent and melt process method. Silk fibers (carpet weaving waste) with dimensions of 8-18 mm were prepared, and recycled polymer with 9 mesh grading was ground. Production boards in 3 thicknesses, 3 mm (tensile test samples), 5 mm (bending test samples, water absorption, and thickness shrinkage), 7 mm (impact resistance test samples) ) with a specific weight of 1 gram per cubic centimeter, hot pressing time and temperature of 12 minutes and 190 degrees Celsius with a pressure of 130 bar, cold pressing time of 6 minutes with a pressure of 50 bar and using the coupling agent N- (2- Aminoethyl)-3-aminopropyltrimethoxysilane was prepared in a constant amount of 2% of the dry weight of the filler. The results showed that, in general, by adding silk fibers to the base polymer, compared to the control samples (pure recycled polycarbonate polymer) and also by increasing the amount of silk fibers, almost all the resistances increased. The amount of water absorption of the constructed composite increased with the increase in the amount of silk fibers, and the thickness absorption was equal to 0% even after 72 hours of immersion in water. The thermal resistance of the pure recycled polymer was higher than the prepared composites, and by adding silk fibers to the base polymer and also by increasing the amount of silk fibers from 10 to 30%, the thermal resistance of the composites decreased.

Keywords: wood composite, recycled polycarbonate, silk fibers, polymer

Procedia PDF Downloads 70
4504 Efficacy of Ethanolic Extract of Aerva javanica Aerial Parts in the Amelioration of CCl4-Induced Hepatotoxicity and Oxidative Damage in Rats

Authors: Mohammad K. Parvez, Ahmed H. Arbab, Mohammed S. Al-Dosari, Adnan J. Al-Rehaily

Abstract:

We investigated ex vivo and in vivo antioxidative and hepatoprotective effect of Aerva javanica. Total ethanol extract of A. javanica aerial parts was prepared, and tested on DCFH-toxicated HepG2 cell in CCl4-injured Wistar rats. MTT-assay was used to determine cell viability, and serum biochemical markers of liver injury as well as histopathology were performed. In vitro DPPH and β-carotene free-radical scavenging assay and phytochemical screening of the extract was done. Furthermore, A. javanica total extract was standardized and validated by HPTLC method. While DCFH-injured cells were recovered to about 56.7% by 100 microg/ml of the extract, a 200 microg/ml dose resulted in hepatocytes recovery by about 90.2%. Oral administration of the extract (100 and 200 mg/kg.bw/day) significantly normalized the serum SGOT, SGPT, GGT, ALP, bilirubin, cholesterol, HDL, LDL, VLDL, TG and MDA levels, including tissue NP-SH and TP in CCl4-injured rats. In addition, the histopathology of dissected liver also revealed that A. javanica cured the tissue lesion compared to reference drug, Silymarin. In vitro assays revealed strong free-radical scavenging ability of the extract and presence of alkaloids, flavonoids, tannins, sterols and saponins where Rutin, a well-known antioxidant flavonoid was identified. Our finding therefore, suggests the therapeutic potential of A. javanica in various liver diseases. However, isolation of the active principles, their mechanism of action and other therapeutic contribution remain to be addressed.

Keywords: Aerva javanica, antioxidant, hepatoprotection, rutin

Procedia PDF Downloads 278
4503 The Differences and the Similarities between Corporate Governance Principles in Islamic Banks and Conventional Banks

Authors: Osama Shibani

Abstract:

Corporate governance effective is critical to the proper functioning of the banking sector and the economy as a whole, the Basel Committee have issued principles of corporate governance inspired from Organisation for Economic Co-operation and Development (OECD), but there is no single model of corporate governance that can work well in every country; each country, or even each organization should develop its own model that can cater for its specific needs and objectives, the corporate governance in Islamic Institutions is unique and offers a particular structure and guided by a control body which is Shariah supervisory Board (SSB), for this reason Islamic Financial Services Board in Malaysia (IFSB) has amended BCBS corporate governance principles commensurate with Islamic financial Institutions to suit the nature of the work of Islamic institutions, this paper highlight these amended by using comparative analysis method in context of the differences of corporate governance structure of Islamic banks and conventional banks. We find few different between principles (Principle 1: The Board's overall responsibilities, Principles 3: Board’s own structure and practices, Principles 9: Compliance, Principle 10: Internal audit, Principle 12: Disclosure and transparency) and there are similarities between principles (Principle 2: Board qualifications and composition, Principles 4: Senior Management (composition and tasks), Principle 6: Risk Management and Principle 8: Risk communication). Finally, we found that corporate governance principles issued by Islamic Financial Services Board (IFSB) are complemented to CG principles of Basel Committee on Banking Supervision (BCBS) with some modifications to suit the composition of Islamic banks, there are deficiencies in the interest of the Basel Committee to Islamic banks.

Keywords: basel committee (BCBS), corporate governance principles, Islamic financial services board (IFSB), agency theory

Procedia PDF Downloads 268
4502 Semi-Autonomous Surgical Robot for Pedicle Screw Insertion on ex vivo Bovine Bone: Improved Workflow and Real-Time Process Monitoring

Authors: Robnier Reyes, Andrew J. P. Marques, Joel Ramjist, Chris R. Pasarikovski, Victor X. D. Yang

Abstract:

Over the past three decades, surgical robotic systems have demonstrated their ability to improve surgical outcomes. The LBR Med is a collaborative robotic arm that is meant to work with a surgeon to streamline surgical workflow. It has 7 degrees of freedom and thus can be easily oriented. Position and torque sensors at each joint allow it to maintain a position accuracy of 150 µm with real-time force and torque feedback, making it ideal for complex surgical procedures. Spinal fusion procedures involve the placement of as many as 20 pedicle screws, requiring a great deal of accuracy due to proximity to the spinal canal and surrounding vessels. Any deviation from intended path can lead to major surgical complications. Assistive surgical robotic systems are meant to serve as collaborative devices easing the workload of the surgeon, thereby improving pedicle screw placement by mitigating fatigue related inaccuracies. Moreover, robotic spinal systems have shown marked improvements over conventional freehanded techniques in both screw placement accuracy and fusion quality and have greatly reduced the need for screw revision, intraoperatively and post-operatively. However, current assistive spinal fusion robots, such as the ROSA Spine, are limited in functionality to positioning surgical instruments. While they offer a small degree of improvement in pedicle screw placement accuracy, they do not alleviate surgeon fatigue, nor do they provide real-time force and torque feedback during screw insertion. We propose a semi-autonomous surgical robot workflow for spinal fusion where the surgeon guides the robot to its initial position and orientation, and the robot drives the pedicle screw accurately into the vertebra. Here, we demonstrate feasibility by inserting pedicle screws into ex-vivo bovine rib bone. The robot monitors position, force and torque with respect to predefined values selected by the surgeon to ensure the highest possible spinal fusion quality. The workflow alleviates the strain on the surgeon by having the robot perform the screw placement while the ability to monitor the process in real-time keeps the surgeon in the system loop. The approach we have taken in terms of level autonomy for the robot reflects its ability to safely collaborate with the surgeon in the operating room without external navigation systems.

Keywords: ex vivo bovine bone, pedicle screw, surgical robot, surgical workflow

Procedia PDF Downloads 148
4501 The Influence of the Variety and Harvesting Date on Haskap Composition and Anti-Diabetic Properties

Authors: Aruma Baduge Kithma Hansanee De Silva

Abstract:

Haskap (Lonicera caerulea L.), also known as blue honeysuckle, is a recently commercialized berry crop in Canada. Haskap berries are rich in polyphenols, including anthocyanins, which are known for potential health-promoting effects. Cyanidin-3-O-glucoside (C3G) is the most prominent anthocyanin of haskap berries. Recent literature reveals the efficacy of C3G in reducing the risk of type 2 diabetes (T2D), which has become an increasingly common health issue around the world. The T2D is characterized as a metabolic disorder of hyperglycemia and insulin resistance. It has been demonstrated that C3G has anti-diabetic effects in various ways, including improvement in insulin sensitivity, and inhibition of activities of carbohydrate-hydrolyzing enzymes, including alpha-amylase and alpha-glucosidase. The goal of this study was to investigate the influence of variety and harvesting date on haskap composition, biological properties, and antidiabetic properties. The polyphenolic compounds present in four commercially grown haskap cultivars, Aurora, Rebecca, Larissa and Evie among five harvesting stages (H1-H5), were extracted separately in 80% ethanol and analyzed to characterize their phenolic profiles. The haskap berries contain different types of polyphenols including flavonoids and phenolic acids. Anthocyanin is the major type of flavonoid. C3G is the most prominent type of anthocyanin, which accounts for 79% of total anthocyanin in all extracts. The variety Larissa at H5 contained the highest average C3G content, and its ethanol extract had the highest (1212.3±63.9 mg/100g FW) while, Evie at H1 contained the lowest C3G content (96.9±40.4 mg/100g FW). The average C3G content of Larissa from H1 – H5 varies from 208 – 1212 mg/100g FW. Quarcetin-3-Rutinoside (Q3Rut) is the major type of flavonol and highest is observed in Rebecca at H4 (47.81 mg/100g FW). The haskap berries also contained phenolic acids, but approximately 95% of the phenolic acids consisted of chlorogenic acid. The cultivar Larissa has a higher level of anthocyanin than the other four cultivars. The highest total phenolic content is observed in Evie at H5 (2.97±1.03 mg/g DW) while the lowest in Rebecca at H1 (1.47±0.96 mg/g DW). The antioxidant capacity of Evie at H5 was higher (14.40±2.21 µmol TE/ g DW) among other cultivars and the lowest observed in Aurora at H3 (5.69±0.34 µmol TE/ g DW). Furthermore, Larissa H5 shows the greatest inhibition of carbohydrate-hydrolyzing enzymes including alpha-glucosidase and alpha-amylase. In conclusion Larissa, at H5 demonstrated highest polyphenol composition and antidiabetic properties.

Keywords: anthocyanin, cyanidin-3-O-glucoside, haskap, type 2 diabetes

Procedia PDF Downloads 439
4500 A Review of Research on Pre-training Technology for Natural Language Processing

Authors: Moquan Gong

Abstract:

In recent years, with the rapid development of deep learning, pre-training technology for natural language processing has made great progress. The early field of natural language processing has long used word vector methods such as Word2Vec to encode text. These word vector methods can also be regarded as static pre-training techniques. However, this context-free text representation brings very limited improvement to subsequent natural language processing tasks and cannot solve the problem of word polysemy. ELMo proposes a context-sensitive text representation method that can effectively handle polysemy problems. Since then, pre-training language models such as GPT and BERT have been proposed one after another. Among them, the BERT model has significantly improved its performance on many typical downstream tasks, greatly promoting the technological development in the field of natural language processing, and has since entered the field of natural language processing. The era of dynamic pre-training technology. Since then, a large number of pre-trained language models based on BERT and XLNet have continued to emerge, and pre-training technology has become an indispensable mainstream technology in the field of natural language processing. This article first gives an overview of pre-training technology and its development history, and introduces in detail the classic pre-training technology in the field of natural language processing, including early static pre-training technology and classic dynamic pre-training technology; and then briefly sorts out a series of enlightening technologies. Pre-training technology, including improved models based on BERT and XLNet; on this basis, analyze the problems faced by current pre-training technology research; finally, look forward to the future development trend of pre-training technology.

Keywords: natural language processing, pre-training, language model, word vectors

Procedia PDF Downloads 32
4499 The Effects of L-Arginine Supplementation on Clinical Symptoms, Quality of Life, and Anal Internal Sphincter Pressure in Patients with Chronic Anal Fissure

Authors: Masoumeh Khailghi Sikaroudi, Mohsen Masoodi, Fazad Shidfar, Meghdad Sedaghat

Abstract:

Background: The hypertonicity of internal anal sphincter resting pressure is one of the main reasons for chronic anal fissures. The aim of this study is to assess the effect of oral administration of L-arginine on anal fissure symptom improvement by relaxation of the internal anal sphincter. Method: Seventy-six chronic anal fissure patients (age: 18-65 years) took part in this randomized, double-blind, placebo-controlled trial study from February 2019 to October 2020 at Rasoul-e-Akram Hospital, Tehran, Iran. Participants were allocated into treatment (L-arginine) or placebo groups. They took a 1000 mg capsule three times a day for one month and were followed up at the end of the first and third months after receiving the intervention. Clinical symptoms, anal sphincter resting pressure, and quality of life (QoL) were completed at baseline and the end of the study. Result: The analysis of data was shown significant improvement in bleeding, fissure size, and pain within each group; however, this effect was more seen in the arginine group compared to the control group at the end of the study (P-values<0.001). Following that, a significant increase in QoL was seen just in patients who were treated with arginine (P-value=0.006). Also, the comparison of anal pressures to baseline and between groups at the end of the study showed a significant reduction in sphincter pressure in treated patients (P-value<0.001, =0.049; respectively). Conclusion: Oral administration of 3000 mg L-arginine can heal chronic anal fissures by reducing anal internal sphincter pressure with fewer side effects. However, a long-term study with more follow-up is recommended.

Keywords: L-arginine, anal fissure, sphincter pressure, clinical symptoms, quality of life

Procedia PDF Downloads 52
4498 Multiple Negative-Differential Resistance Regions Based on AlN/GaN Resonant Tunneling Structures by the Vertical Growth of Molecular Beam Epitaxy

Authors: Yao Jiajia, Wu Guanlin, LIU Fang, Xue Junshuai, Zhang Jincheng, Hao Yue

Abstract:

Resonant tunneling diodes (RTDs) based on GaN have been extensively studied. However, no results of multiple logic states achieved by RTDs were reported by the methods of epitaxy in the GaN materials. In this paper, the multiple negative-differential resistance regions by combining two discrete double-barrier RTDs in series have been first demonstrated. Plasma-assisted molecular beam epitaxy (PA-MBE) was used to grow structures consisting of two vertical RTDs. The substrate was a GaN-on-sapphire template. Each resonant tunneling structure was composed of a double barrier of AlN and a single well of GaN with undoped 4-nm space layers of GaN on each side. The AlN barriers were 1.5 nm thick, and the GaN well was 2 nm thick. The resonant tunneling structures were separated from each other by 30-nm thick n+ GaN layers. The bottom and top layers of the structures, grown neighboring to the spacer layers that consist of 200-nm-thick n+ GaN. These devices with two tunneling structures exhibited uniform peaks and valleys current and also had two negative differential resistance NDR regions equally spaced in bias voltage. The current-voltage (I-V) characteristics of resonant tunneling structures with diameters of 1 and 2 μm were analyzed in this study. These structures exhibit three stable operating points, which are investigated in detail. This research demonstrates that using molecular beam epitaxy MBE to vertically grow multiple resonant tunneling structures is a promising method for achieving multiple negative differential resistance regions and stable logic states. These findings have significant implications for the development of digital circuits capable of multi-value logic, which can be achieved with a small number of devices.

Keywords: GaN, AlN, RTDs, MBE, logic state

Procedia PDF Downloads 69
4497 Zeolite Supported Iron-Sensitized TIO₂ for Tetracycline Photocatalytic ‎Degradation under Visible Light: A Comparison between Doping and Ion ‎Exchange ‎

Authors: Ghadeer Jalloul, Nour Hijazi, Cassia Boyadjian, Hussein Awala, Mohammad N. Ahmad, ‎Ahmad Albadarin

Abstract:

In this study, we applied Fe-sensitized TiO₂ supported over embryonic Beta zeolite (BEA) zeolite ‎for the photocatalytic degradation of Tetracycline (TC) antibiotic under visible light. Four different ‎samples having 20, 40, 60, and 100% w/w as a ratio of TiO₂/BEA were prepared. The ‎immobilization of solgel TiO₂ (33 m²/g) over BEA (390 m²/g) increased its surface area to (227 ‎m²/g) and enhanced its adsorption capacity from 8% to 19%. To expand the activity of TiO₂ ‎photocatalyst towards the visible light region (λ>380 nm), we explored two different metal ‎sensitization techniques with Iron ions (Fe³⁺). In the ion-exchange method, the substitutional cations ‎in the zeolite in TiO₂/BEA were exchanged with (Fe³⁺) in an aqueous solution of FeCl₃. In the ‎doping technique, solgel TiO₂ was doped with (Fe³⁺) from FeCl₃ precursor during its synthesis and ‎before its immobilization over BEA. (Fe-TiO₂/BEA) catalysts were characterized using SEM, XRD, ‎BET, UV-VIS DRS, and FTIR. After testing the performance of the various ion-exchanged catalysts ‎under blue and white lights, only (Fe-TiO₂/BEA 60%) showed better activity as compared to pure ‎TiO₂ under white light with 100 ppm initial catalyst concentration and 20 ppm TC concentration. As ‎compared to ion-exchanged (Fe-TiO₂/BEA), doped (Fe-TiO₂/BEA) resulted in higher photocatalytic ‎efficiencies under blue and white lights. The 3%-Fe-doped TiO₂/BEA removed 92% of TC ‎compared to 54% by TiO₂ under white light. The catalysts were also tested under real solar ‎irradiations. This improvement in the photocatalytic performance of TiO₂ was due to its higher ‎adsorption capacity due to BEA support combined with the presence of Iron ions that enhance the ‎visible light absorption and minimize the recombination effect by the charge carriers. ‎

Keywords: Tetracycline, photocatalytic degradation, immobilized TiO₂, zeolite, iron-doped TiO₂, ion-exchange

Procedia PDF Downloads 83
4496 Adaptation of the Scenario Test for Greek-speaking People with Aphasia: Reliability and Validity Study

Authors: Marina Charalambous, Phivos Phylactou, Thekla Elriz, Loukia Psychogios, Jean-Marie Annoni

Abstract:

Background: Evidence-based practices for the evaluation and treatment of people with aphasia (PWA) in Greek are mainly impairment-based. Functional and multimodal communication is usually under assessed and neglected by clinicians. This study explores the adaptation and psychometric testing of the Greek (GR) version of The Scenario Test. The Scenario Test assesses the everyday functional communication of PWA in an interactive multimodal communication setting with the support of an active communication facilitator. Aims: To define the reliability and validity of The Scenario Test GR and discuss its clinical value. Methods & Procedures: The Scenario Test-GR was administered to 54 people with chronic stroke (6+ months post-stroke): 32 PWA and 22 people with stroke without aphasia. Participants were recruited from Greece and Cyprus. All measures were performed in an interview format. Standard psychometric criteria were applied to evaluate reliability (internal consistency, test-retest, and interrater reliability) and validity (construct and known – groups validity) of the Scenario Test GR. Video analysis was performed for the qualitative examination of the communication modes used. Outcomes & Results: The Scenario Test-GR shows high levels of reliability and validity. High scores of internal consistency (Cronbach’s α = .95), test-retest reliability (ICC = .99), and interrater reliability (ICC = .99) were found. Interrater agreement in scores on individual items fell between good and excellent levels of agreement. Correlations with a tool measuring language function in aphasia (the Aphasia Severity Rating Scale of the Boston Diagnostic Aphasia Examination), a measure of functional communication (the Communicative Effectiveness Index), and two instruments examining the psychosocial impact of aphasia (the Stroke and Aphasia Quality of Life questionnaire and the Aphasia Impact Questionnaire) revealed good convergent validity (all ps< .05). Results showed good known – groups validity (Mann-Whitney U = 96.5, p < .001), with significantly higher scores for participants without aphasia compared to those with aphasia. Conclusions: The psychometric qualities of The Scenario Test-GR support the reliability and validity of the tool for the assessment of functional communication for Greek-speaking PWA. The Scenario Test-GR can be used to assess multimodal functional communication, orient aphasia rehabilitation goal setting towards the activity and participation level, and be used as an outcome measure of everyday communication. Future studies will focus on the measurement of sensitivity to change in PWA with severe non-fluent aphasia.

Keywords: the scenario test GR, functional communication assessment, people with aphasia (PWA), tool validation

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4495 Causes of Pokir in the Budgeting Process: Case Study in the Province of Jakarta, Indonesia

Authors: Tri Nopiyanto, Rahardhyani Dwiannisa, Arief Ismaryanto

Abstract:

One main issue for a certain region in order to achieve development is if the government that consists of the executive, legislative and judicial board are able to work together. However, there are certain conditions that these boards are the sources of conflict, especially between the executive and legislative board. One of the example of the conflict is between the Local Government and Legislative Board (DPRD) in the Province of Jakarta in 2015. The cause of this conflict is because of the occurrence of pokir (pokok pikiran or ideas of budgeting). Pokir is driven by a budgeting plan that is arranged by DPRD that is supposed to be sourced from the aspiration of the people and delivered 5 months before the legalization of Local Government Budget (APBD), but the current condition in Jakarta is that pokir is a project by DPRD members itself and delivered just 3 days before the legalization in order to facilitate the interests of the members of the legislative. This paper discusses how pokir happens and what factors caused it. This paper uses political budgeting theory by Andy Norton and Diane Elson to analyze the issue. The method used in this paper is qualitative to collect the data and solve the problem of this research. The methods involved are in depth interview, experimental questionnaire, and literature studies. Results of this research are that Pokir occurs because of the distribution of power among DPRD members, between parties, executive, and legislative board. Beside that, Pokir also occurs because of the lack of the people’s participation in budgeting process and monitoring. Other than that, this paper also found that pokir also happens because of the budgeting system that is not able to provide a clean budgeting process, so it enables the creation of certain slots to add pokir into the budgets. Pokir also affects the development of Jakarta that goes through stagnation. This research recommends the implementation of e-budgeting to prevent the occurrence of pokir itself in the Province of Jakarta.

Keywords: legislative and executive board, Jakarta, political budgeting, Pokir

Procedia PDF Downloads 247
4494 Analyzing the Shearing-Layer Concept Applied to Urban Green System

Authors: S. Pushkar, O. Verbitsky

Abstract:

Currently, green rating systems are mainly utilized for correctly sizing mechanical and electrical systems, which have short lifetime expectancies. In these systems, passive solar and bio-climatic architecture, which have long lifetime expectancies, are neglected. Urban rating systems consider buildings and services in addition to neighborhoods and public transportation as integral parts of the built environment. The main goal of this study was to develop a more consistent point allocation system for urban building standards by using six different lifetime shearing layers: Site, Structure, Skin, Services, Space, and Stuff, each reflecting distinct environmental damages. This shearing-layer concept was applied to internationally well-known rating systems: Leadership in Energy and Environmental Design (LEED) for Neighborhood Development, BRE Environmental Assessment Method (BREEAM) for Communities, and Comprehensive Assessment System for Building Environmental Efficiency (CASBEE) for Urban Development. The results showed that LEED for Neighborhood Development and BREEAM for Communities focused on long-lifetime-expectancy building designs, whereas CASBEE for Urban Development gave equal importance to the Building and Service Layers. Moreover, although this rating system was applied using a building-scale assessment, “Urban Area + Buildings” focuses on a short-lifetime-expectancy system design, neglecting to improve the architectural design by considering bio-climatic and passive solar aspects.

Keywords: green rating system, urban community, sustainable design, standardization, shearing-layer concept, passive solar architecture

Procedia PDF Downloads 557