Search results for: ternary system
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 17732

Search results for: ternary system

3302 Review of the Road Crash Data Availability in Iraq

Authors: Abeer K. Jameel, Harry Evdorides

Abstract:

Iraq is a middle income country where the road safety issue is considered one of the leading causes of deaths. To control the road risk issue, the Iraqi Ministry of Planning, General Statistical Organization started to organise a collection system of traffic accidents data with details related to their causes and severity. These data are published as an annual report. In this paper, a review of the available crash data in Iraq will be presented. The available data represent the rate of accidents in aggregated level and classified according to their types, road users’ details, and crash severity, type of vehicles, causes and number of causalities. The review is according to the types of models used in road safety studies and research, and according to the required road safety data in the road constructions tasks. The available data are also compared with the road safety dataset published in the United Kingdom as an example of developed country. It is concluded that the data in Iraq are suitable for descriptive and exploratory models, aggregated level comparison analysis, and evaluation and monitoring the progress of the overall traffic safety performance. However, important traffic safety studies require disaggregated level of data and details related to the factors of the likelihood of traffic crashes. Some studies require spatial geographic details such as the location of the accidents which is essential in ranking the roads according to their level of safety, and name the most dangerous roads in Iraq which requires tactic plan to control this issue. Global Road safety agencies interested in solve this problem in low and middle-income countries have designed road safety assessment methodologies which are basing on the road attributes data only. Therefore, in this research it is recommended to use one of these methodologies.

Keywords: road safety, Iraq, crash data, road risk assessment, The International Road Assessment Program (iRAP)

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3301 Modified Lot Quality Assurance Sampling (LQAS) Model for Quality Assessment of Malaria Parasite Microscopy and Rapid Diagnostic Tests in Kano, Nigeria

Authors: F. Sarkinfada, Dabo N. Tukur, Abbas A. Muaz, Adamu A. Yahuza

Abstract:

Appropriate Quality Assurance (QA) of parasite-based diagnosis of malaria to justify Artemisinin-based Combination Therapy (ACT) is essential for Malaria Programmes. In Low and Middle Income Countries (LMIC), resource constrain appears to be a major challenge in implementing the conventional QA system. We designed and implemented a modified LQAS model for QA of malaria parasite (MP) microscopy and RDT in a State Specialist Hospital (SSH) and a University Health Clinic (UHC) in Kano, Nigeria. The capacities of both facilities for MP microscopy and RDT were assessed before implementing a modified LQAS over a period of 3 months. Quality indicators comprising the qualities of blood film and staining, MP positivity rates, concordance rates, error rates (in terms of false positives and false negatives), sensitivity and specificity were monitored and evaluated. Seventy one percent (71%) of the basic requirements for malaria microscopy was available in both facilities, with the absence of certifies microscopists, SOPs and Quality Assurance mechanisms. A daily average of 16 to 32 blood samples were tested with a blood film staining quality of >70% recorded in both facilities. Using microscopy, the MP positivity rates were 50.46% and 19.44% in SSH and UHS respectively, while the MP positivity rates were 45.83% and 22.78% in SSH and UHS when RDT was used. Higher concordance rates of 88.90% and 93.98% were recorded in SSH and UHC respectively using microscopy, while lower rates of 74.07% and 80.58% in SSH and UHC were recorded when RDT was used. In both facilities, error rates were higher when RDT was used than with microscopy. Sensitivity and specificity were higher when microscopy was used (95% and 84% in SSH; 94% in UHC) than when RDT was used (72% and 76% in SSH; 78% and 81% in UHC). It could be feasible to implement an integrated QA model for MP microscopy and RDT using modified LQAS in Malaria Control Programmes in Low and Middle Income Countries that might have resource constrain for parasite-base diagnosis of malaria to justify ACT treatment.

Keywords: malaria, microscopy, quality assurance, RDT

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3300 Teaching Critical Thinking in Post-Conflict Countries: The University of Liberia

Authors: Kamille Beye

Abstract:

Critical thinking is a topic that has been disputed in the field of education for decades, but many resulting debates have centered around strengthening critical thinking capabilities in the societies, workforces, and educational centers of the global north. In contrast, this paper provides an analysis of the teaching of critical thinking in Liberia, which has been ravaged by years of war and a recent Ebola outbreak. These crises have decimated the Liberian education sector, leading to a loss of teaching capacities that are essential to providing critical thinking education. Until recently, critical thinking had no seat at the table when the future needs of the country were discussed by the government and non-governmental agencies. Now, the University of Liberia has a bold goal to become one of the top twenty universities in West Africa in the next seven years, which has led to a focus on teaching critical thinking skills to improve learning. This paper argues that critical thinking is essential to strengthening not only the Liberian education system, but for promoting peace amongst community members, and yet it suggests that commitments to the teaching of critical thinking in Liberia have hitherto been overly superficial. Based on an initial scoping study, this paper will examine the potential impacts of teaching critical thinking skills to undergraduate students in the William V. S. Tubman School of Education at the University of Liberia on continued peacebuilding and reconstruction efforts of the country. The research contends that if critical thinking skills are taught, practiced and continually utilized, teachers and students will have the ability to engage with information and negotiate challenges to solutions in ways that are beneficial to the communities in which they live. The research will use a variety of methods, that include the California Critical Thinking Disposition Inventory. This research will demonstrate that critical thinking skills are not only needed for entering the workforce, but necessary for negotiating and expressing the needs and desires of local communities in a peaceful way.

Keywords: critical thinking, higher education, Liberia, peacebuilding, post-conflict

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3299 Development, Testing, and Application of a Low-Cost Technology Sulphur Dioxide Monitor as a Tool for use in a Volcanic Emissions Monitoring Network

Authors: Viveka Jackson, Erouscilla Joseph, Denise Beckles, Thomas Christopher

Abstract:

Sulphur Dioxide (SO2) has been defined as a non-flammable, non-explosive, colourless gas, having a pungent, irritating odour, and is one of the main gases emitted from volcanoes. Sulphur dioxide has been recorded in concentrations hazardous to humans (0.25 – 0.5 ppm (~650 – 1300 μg/m3), downwind of many volcanoes and hence warrants constant air-quality monitoring around these sites. It has been linked to an increase in chronic respiratory disease attributed to long-term exposures and alteration in lung and other physiological functions attributed to short-term exposures. Sulphur Springs in Saint Lucia is a highly active geothermal area, located within the Soufrière Volcanic Centre, and is a park widely visited by tourists and locals. It is also a current source of continuous volcanic emissions via its many fumaroles and bubbling pools, warranting concern by residents and visitors to the park regarding the effects of exposure to these gases. In this study, we introduce a novel SO2 measurement system for the monitoring and quantification of ambient levels of airborne volcanic SO2 using low-cost technology. This work involves the extensive production of low-cost SO2 monitors/samplers, as well as field examination in tandem with standard commercial samplers (SO2 diffusion tubes). It also incorporates community involvement in the volcanic monitoring process as non-professional users of the instrument. We intend to present the preliminary monitoring results obtained from the low-cost samplers, to identify the areas in the Park exposed to high concentrations of ambient SO2, and to assess the feasibility of the instrument for non-professional use and application in volcanic settings

Keywords: ambient SO2, community-based monitoring, risk-reduction, sulphur springs, low-cost

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3298 Different Motor Inhibition Processes in Action Selection Stage: A Study with Spatial Stroop Paradigm

Authors: German Galvez-Garcia, Javier Albayay, Javiera Peña, Marta Lavin, George A. Michael

Abstract:

The aim of this research was to investigate whether the selection of the actions needs different inhibition processes during the response selection stage. In Experiment 1, we compared the magnitude of the Spatial Stroop effect, which occurs in response selection stage, in two motor actions (lifting vs reaching) when the participants performed both actions in the same block or in different blocks (mixed block vs. pure blocks).Within pure blocks, we obtained faster latencies when lifting actions were performed, but no differences in the magnitude of the Spatial Stroop effect were observed. Within mixed block, we obtained faster latencies as well as bigger-magnitude for Spatial Stroop effect when reaching actions were performed. We concluded that when no action selection is required (the pure blocks condition), inhibition works as a unitary system, whereas in the mixed block condition, where action selection is required, different inhibitory processes take place within a common processing stage. In Experiment 2, we investigated this common processing stage in depth by limiting participants’ available resources, requiring them to engage in a concurrent auditory task within a mixed block condition. The Spatial Stroop effect interacted with Movement as it did in Experiment 1, but it did not significantly interact with available resources (Auditory task x Spatial Stroop effect x Movement interaction). Thus, we concluded that available resources are distributed equally to both inhibition processes; this reinforces the likelihood of there being a common processing stage in which the different inhibitory processes take place.

Keywords: inhibition process, motor processes, selective inhibition, dual task

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3297 Prevalence of SARS-CoV-2 Infection and Associated Risk Factors in Selected Health Facilities of Tigray, Ethiopia: Cross-Sectional Study Design, 2023

Authors: Weldegerima Gebremedhin Hagos

Abstract:

Background: The Coronavirus disease of 2019 (COVID-19) is a catastrophic emerging global health threat caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). COVID-19 has a wide range of complications and sequels. It is devastating in developing countries, causing serious health and socioeconomic crises as a result of the increasingly overburdened healthcare system. Ethiopia reported the first case of SARS-CoV-2 on 13th March 2020, with community transmission ensuing by mid-May. The aim of this study was conducted to determine the prevalence of SARS-CoV-2 infection in Tigray, Ethiopia. Methods: Facility-based correctional study designs were used on a total of 380 study participants from March 2023 up to May 2023 in two general hospitals and one comprehensive specialized hospital in Tigray, Ethiopia. A pre-structured questionnaire was used to assess information regarding the socio-demographic, clinical data and other risk factors. A nasal swap was taken by trained health professionals, and the laboratory analysis was done by RT-PCR (quant studio 7-flex, applied biosystems) in Tigrai Health Research Institute and Mekelle University Medical Microbiology Research Laboratory. Result: The mean age of the study participants was 31 (SD+/-3.5) years, with 65% being male and 35% female. The overall seropositivity of sars-cov-2 among the study participants was 5.5%. The prevalence was higher in males (6.2%) than females which were (4.7%). Sars-cov-2 infection was significantly associated with a history of lack of vaccination (p-value 0.002). There was no significant association between seropositivity and demographic factors (P > 0.05). Conclusion: The seroprevalence of SARS-CoV-2 among the study participants is high. Those study participants with a previous history of vaccination have a low probability of developing COVID-19 infection. A low SARS-CoV-2 infection rate was recorded in those who frequently use masks.

Keywords: prevalence, SARS-CoV-2, infection, risk factors

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3296 Deltamethrin-Induces Oxidative Stress to the Freshwater Ciliate Model: Paramecium tetraurelia

Authors: Amamra Ryma, Djebar Mohamed Reda, Moumeni Ouissem, Otmani Hadjer, Berrebbah Houria

Abstract:

The problem of environmental contamination by the excessive use of organics cannot be neglected. Extensive application is usually companied with serious problems and health risk. It is established that many chemicals, in common use, can produce some toxic effects on biological systems through their mode of action or by production of free radicals that damage all cell compounds. Deltamethrin, a widely used type II pyrethroid pesticide, is one of the most common contaminants in freshwater aquatic system. In this study, we investigate the effects of deltamethrin exposure on the induction of oxidative stress to the freshwater ciliate Paramecium tetraurelia. After the treatment of paramecium cells with increasing concentrations of insecticide, we followed up the growth kinetics, generation time and the percentage response. Also, we studied the variation in biomarkers of stress such as: GSH content, GST, GPX and CAT activities. Our results showed a significant decrease in the proliferation of cells correlated by the decrease in generation number and the increase in generation time. Also, we noted an inhibition in the percentage response. The monitoring of biomarkers revealed depletion in GSH content in a proportional and dose dependent manner accompanied by an increase in the GST activity. In parallel, a strong induction in the CAT and GPX activities was noted specially for the highest dose. In summary, under the current experimental conditions, deltamethrin is highly toxic to the freshwater ciliate Paramecium tetraurelia. Exposure to low concentrations showed significant adverse on growth accompanied with the induction of oxidative damage supported by the decrease in GSH content and the intensification of the antioxidant enzymes.

Keywords: deltamethrin, Paramecium tetraurelia, growth, oxidative stress, biomarkers, antioxidant

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3295 Linear Decoding Applied to V5/MT Neuronal Activity on Past Trials Predicts Current Sensory Choices

Authors: Ben Hadj Hassen Sameh, Gaillard Corentin, Andrew Parker, Kristine Krug

Abstract:

Perceptual decisions about sequences of sensory stimuli often show serial dependence. The behavioural choice on one trial is often affected by the choice on previous trials. We investigated whether the neuronal signals in extrastriate visual area V5/MT on preceding trials might influence choice on the current trial and thereby reveal the neuronal mechanisms of sequential choice effects. We analysed data from 30 single neurons recorded from V5/MT in three Rhesus monkeys making sequential choices about the direction of rotation of a three-dimensional cylinder. We focused exclusively on the responses of neurons that showed significant choice-related firing (mean choice probability =0.73) while the monkey viewed perceptually ambiguous stimuli. Application of a wavelet transform to the choice-related firing revealed differences in the frequency band of neuronal activity that depended on whether the previous trial resulted in a correct choice for an unambiguous stimulus that was in the neuron’s preferred direction (low alpha and high beta and gamma) or non-preferred direction (high alpha and low beta and gamma). To probe this in further detail, we applied a regularized linear decoder to predict the choice for an ambiguous trial by referencing the neuronal activity of the preceding unambiguous trial. Neuronal activity on a previous trial provided a significant prediction of the current choice (61% correc, 95%Cl~52%t), even when limiting analysis to preceding trials that were correct and rewarded. These findings provide a potential neuronal signature of sequential choice effects in the primate visual cortex.

Keywords: perception, decision making, attention, decoding, visual system

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3294 An Unbiased Profiling of Immune Repertoire via Sequencing and Analyzing T-Cell Receptor Genes

Authors: Yi-Lin Chen, Sheng-Jou Hung, Tsunglin Liu

Abstract:

Adaptive immune system recognizes a wide range of antigens via expressing a large number of structurally distinct T cell and B cell receptor genes. The distinct receptor genes arise from complex rearrangements called V(D)J recombination, and constitute the immune repertoire. A common method of profiling immune repertoire is via amplifying recombined receptor genes using multiple primers and high-throughput sequencing. This multiplex-PCR approach is efficient; however, the resulting repertoire can be distorted because of primer bias. To eliminate primer bias, 5’ RACE is an alternative amplification approach. However, the application of RACE approach is limited by its low efficiency (i.e., the majority of data are non-regular receptor sequences, e.g., containing intronic segments) and lack of the convenient tool for analysis. We propose a computational tool that can correctly identify non-regular receptor sequences in RACE data via aligning receptor sequences against the whole gene instead of only the exon regions as done in all other tools. Using our tool, the remaining regular data allow for an accurate profiling of immune repertoire. In addition, a RACE approach is improved to yield a higher fraction of regular T-cell receptor sequences. Finally, we quantify the degree of primer bias of a multiplex-PCR approach via comparing it to the RACE approach. The results reveal significant differences in frequency of VJ combination by the two approaches. Together, we provide a new experimental and computation pipeline for an unbiased profiling of immune repertoire. As immune repertoire profiling has many applications, e.g., tracing bacterial and viral infection, detection of T cell lymphoma and minimal residual disease, monitoring cancer immunotherapy, etc., our work should benefit scientists who are interested in the applications.

Keywords: immune repertoire, T-cell receptor, 5' RACE, high-throughput sequencing, sequence alignment

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3293 Racial and Ethnic Health Disparities: An Investigation of the Relationship between Race, Ethnicity, Health Care Access, and Health Status

Authors: Dorcas Matowe

Abstract:

Inequality in health care for racial and ethnic minorities continues to be a growing concern for many Americans. Some of the barriers hindering the elimination of health disparities include lack of insurance, socioeconomic status (SES), and racism. This study will specifically focus on the association between some of these factors- health care access, which includes insurance coverage and frequency of doctor visits, race, ethnicity, and health status. The purpose of this study will be to address the following questions: is having health insurance associated with increased doctor visits? Are racial and ethnic minorities with health insurance more or less likely to see a doctor? Is the association between having health insurance moderated by being an ethnic minority? Given the current implications of the 2010 Affordable Care Act, this study will highlight the need to prioritize health care access for minorities and confront institutional racism. Critical Race Theory (CRT) will demonstrate how racism has reinforced these health disparities. This quantitative study design will analyze secondary data from the 2015 Behavioral Risk Factor Surveillance System (BRFSS) questionnaire, a telephone survey conducted annually in all 50 states and three US territories by state health departments in conjunction with the Center for Disease Control (CDC). Non-identifying health-related data is gathered annually from over 400,000 adults 18 years and above about their health status and use of preventative services. Through Structural Equation Modeling (SEM), the relationship between the predictor variables of health care access, race, and ethnicity, the criterion variable of health status, and the latent variables of emotional support and life satisfaction will be examined. It is hypothesized that there will be an interaction between certain racial and ethnic minorities who went to see a doctor, had insurance coverage, experienced racism, and the quality of their health status, emotional support, and life satisfaction.

Keywords: ethnic minorities, health disparities, health access, racism

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3292 Relationship Between Reading Comprehension and Achievement in Science Among Grade Eleven Bilingual Students in a Secondary School, Thailand

Authors: Simon Mauma Efange

Abstract:

The main aims of this research were to describe, in co-relational terms, the relationship, if any, between reading comprehension and academic achievement in science studied at the secondary level and, secondly, to find out possible trends in gender differences, such as whether boys would perform better than girls or vice versa. This research employed a quantitative design. Two kinds of instruments were employed: the Oxford Online Placement Test and the Local Assessment System Test. The Oxford Online Placement Test assesses students' English level quickly and easily. The results of these tests were subjected to statistical analysis using a special statistical software called SPSS. Statistical tools such as mean, standard deviation, percentages, frequencies, t-tests, and Pearson’s coefficient of correlation were used for the analysis of the results. Results of the t-test showed that the means are significantly different. Calculating the p-value revealed that the results were extremely statistically significant at p <.05. The value of r (Pearson correlation coefficient) was 0.2868. Although technically there is a positive correlation, the relationship between the variables is only weak (the closer the value is to zero, the weaker the relationship). However, in conclusion, calculations from the t-test using SPSS revealed that the results were statistically significant at p <.05, confirming a relationship between the two variables, and high scores in reading will give rise to slightly high scores in science. The research also revealed that having a high score in reading comprehension doesn’t necessarily mean having a high score in science or vice versa. Female subjects performed much better than male subjects in both tests, which is in line with the literature reviewed for this research.

Keywords: achievement in science, achievement in English, and bilingual students, relationship

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3291 Numerical Investigation of Entropy Signatures in Fluid Turbulence: Poisson Equation for Pressure Transformation from Navier-Stokes Equation

Authors: Samuel Ahamefula Mba

Abstract:

Fluid turbulence is a complex and nonlinear phenomenon that occurs in various natural and industrial processes. Understanding turbulence remains a challenging task due to its intricate nature. One approach to gain insights into turbulence is through the study of entropy, which quantifies the disorder or randomness of a system. This research presents a numerical investigation of entropy signatures in fluid turbulence. The work is to develop a numerical framework to describe and analyse fluid turbulence in terms of entropy. This decomposes the turbulent flow field into different scales, ranging from large energy-containing eddies to small dissipative structures, thus establishing a correlation between entropy and other turbulence statistics. This entropy-based framework provides a powerful tool for understanding the underlying mechanisms driving turbulence and its impact on various phenomena. This work necessitates the derivation of the Poisson equation for pressure transformation of Navier-Stokes equation and using Chebyshev-Finite Difference techniques to effectively resolve it. To carry out the mathematical analysis, consider bounded domains with smooth solutions and non-periodic boundary conditions. To address this, a hybrid computational approach combining direct numerical simulation (DNS) and Large Eddy Simulation with Wall Models (LES-WM) is utilized to perform extensive simulations of turbulent flows. The potential impact ranges from industrial process optimization and improved prediction of weather patterns.

Keywords: turbulence, Navier-Stokes equation, Poisson pressure equation, numerical investigation, Chebyshev-finite difference, hybrid computational approach, large Eddy simulation with wall models, direct numerical simulation

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3290 University Students Sport’s Activities Assessment in Harsh Weather Conditions

Authors: Ammar S. M. Moohialdin, Bambang T. Suhariadi, Mohsin Siddiqui

Abstract:

This paper addresses the application of physiological status monitoring (PSM) for assessing the impact of harsh weather conditions on sports activities in universities in Saudi Arabia. Real sports measurement was conducted during sports activities such that the physiological status (HR and BR) of five students were continuously monitored by using Zephyr BioHarnessTM 3.0 sensors in order to identify the physiological bonds and zones. These bonds and zones were employed as indicators of the associated physiological risks of the performed sports activities. Furthermore, a short yes/no questionnaire was applied to collect information on participants’ health conditions and opinions of the applied PSM sensors. The results show the absence of a warning system as a protective aid for the hazardous levels of extremely hot and humid weather conditions that may cause dangerous and fatal circumstances. The applied formulas for estimating maximum HR provides accurate estimations for Maximum Heart Rate (HRmax). The physiological results reveal that the performed activities by the participants are considered the highest category (90–100%) in terms of activity intensity. This category is associated with higher HR, BR and physiological risks including losing the ability to control human body behaviors. Therefore, there is a need for immediate intervention actions to reduce the intensity of the performed activities to safer zones. The outcomes of this study assist the safety improvement of sports activities inside universities and athletes performing their sports activities. To the best of our knowledge, this is the first paper to represent a special case of the application of PSM technology for assessing sports activities in universities considering the impacts of harsh weather conditions on students’ health and safety.

Keywords: physiological status monitoring (PSM), heart rate (HR), breathing rate (BR), Arabian Gulf

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3289 Effects of Using Clinical Practice Guidelines for Caring for Patients with Severe Sepsis or Septic Shock on Clinical Outcomes Based on the Sepsis Bundle Protocol at the ICU of Songkhla Hospital Thailand

Authors: Pornthip Seangsanga

Abstract:

Sepsis or septic shock needs urgent care because it is a cause of the high mortality rate if patients do not receive timely treatment. Songkhla Hospital does not have a clear system or clinical practice guidelines for treatment of patients with severe sepsis or septic shock, which contributes to the said problem.To compare clinical outcomes based on the protocol after using the clinical guidelines between the Emergency Room, Intensive Care Unit, and the Ward. This quasi-experimental study was conducted on the population and 50 subjects who were diagnosed with severe sepsis or septic shock from December 2013 to May 2014. The data were collected using a nursing care and referring record form for patients with severe sepsis or septic shock at Songkhla Hospital. The record form had been tested for its validity by three experts, and the IOC was 1.The mortality rate in patients with severe sepsis or septic shock who were moved from the ER to the ICU was significantly lower than that of those patients moved from the Ward to the ICU within 48 hours. This was because patients with severe sepsis or septic shock who were moved from the ER to the ICU received more fluid within the first six hours according to the protocol which helped patients to have adequate tissue perfusion within the first six hours, and that helped improve blood flow to the kidneys, and the patients’ urine was found to be with a higher quantity of 0.5 cc/kg/hr, than those patients who were moved from the Ward to the ICU. This study shows that patients with severe sepsis or septic shock need to be treated immediately. Using the clinical practice guidelines along with timely diagnosis and treatment based on the sepsis bundle in giving sufficient and suitable amount of fluid to help improve blood circulation and blood pressure can clearly prevent or reduce severity of complications.

Keywords: clinical practice guidelines, caring, septic shock, sepsis bundle protocol

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3288 Research on Old Community Planning Strategy in Mountainous City from The Perspective of Physical Activity: A Case Study of Daxigou Street Community, Chongqing

Authors: Yang Liandong

Abstract:

The rapid development of cities has triggered a series of urban health problems. Residents' daily lives have generally changed to long-term unhealthy work and rest, and the prevalence of chronic diseases in the population is on the rise. Promoting physical activity is an effective way to enhance the population's health and reduce the risk of various chronic diseases. As the most basic unit of the city, the community is the living space where residents use the highest frequency of daily activities and also the best space carrier for people to carry out all kinds of physical activities, and its planning research is of great significance for promoting physical activities. Under special conditions, the old communities in mountainous cities present compact and three-dimensional spatial characteristics, and there are problems such as disordered spatial organization, scattered distribution, and low utilization rates. This paper selects four communities in Daxigou Street, Yuzhong District, Chongqing as the research object, analyzes the current situation of the research cases through literature combing and field investigation and interviews, and puts forward the planning strategies for promoting physical activity in old communities in mountain cities from four aspects: building a convenient and smooth public space system, creating a diversified and shared activity space, creating a beautiful and healing community landscape, and providing convenient and perfect supporting facilities, to provide a certain reference for the healthy development of old communities in mountain cities.

Keywords: physical activity, community planning, old communities in mountain cities, public space optimization, spatial fairness

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3287 Effect of Whole Body Vibration on Posture Stability and Planter Pressure in Patients with Diabetic Neuropathy

Authors: Azza M. Atya, Mahmoud M. Nasser

Abstract:

Background/ /Significance: Peripheral neuropathy is one of the long term serious complications of diabetes, which may attribute to postural instability and alteration of planter pressure. Whole body vibration (WBV) is a somatosensory stimulation type of exercise that has been emerged in sport training and rehabilitation of neuromuscular disorders. Purpose: The aim of this study was to investigate the effect of whole Body Vibration on antroposterior (AP), mediolateral (ML) posture stability and planter foot pressure in patients with diabetic neuropathy. Subjects: forty diabetic patients with moderate peripheral neuropathy aged from 35 to 50 years, were randomly assigned to WBV group (n=20) and control group (n=20). Methods and Materials: the WBV intervention consisted of three session weekly for 8 weeks (frequency 20 Hz, peak-to peak displacement 4mm, acceleration 3.5 g). Biodex balance system was used for postural stability assessment and the foot scan plate was used to measure the mean peak pressure under the first and lesser metatarsals. The main Outcome measures were antroposterior stability index (APSI), mediolateral stability index (MLSI), overall stability index (OSI),and mean peak foot pressure. Analyses: Statistical analysis was performed using the SPSS software package (SPSS for Windows Release 18.0). T-test was used to compare between the pre- and post-treatment values between and within groups. Results: For the 40 study participants (18male and 22 females) there were no between-group differences at baseline. At the end of 8 weeks, Subjects in WBV group experienced significant increase in postural stability with a reduction of mean peak of planter foot pressure (P<0.05) compared with the control group. Conclusion: The result suggests that WBV is an effective therapeutic modality for increasing postural stability and reducing planter pressure in patients with diabetic neuropathy.

Keywords: whole body vibration, diabetic neuropathy, posture stability, foot pressure

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3286 Remote Sensing and GIS Integration for Paddy Production Estimation in Bali Province, Indonesia

Authors: Sarono, Hamim Zaky Hadibasyir, dan Ridho Kurniawan

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Estimation of paddy production is one of the areas that can be examined using the techniques of remote sensing and geographic information systems (GIS) in the field of agriculture. The purpose of this research is to know the amount of the paddy production estimation and how remote sensing and geographic information systems (GIS) are able to perform analysis of paddy production estimation in Tegalallang and Payangan Sub district, Bali Province, Indonesia. The method used is the method of land suitability. This method associates a physical parameters which are to be embodied in the smallest unit of a mapping that represents a mapping unit in a particular field and connecting with its field productivity. Analysis of estimated production using standard land suitability from FAO using matching technique. The parameters used to create the land unit is slope (FAO), climate classification (Oldeman), landform (Prapto Suharsono), and soil type. Land use map consist of paddy and non paddy field information obtained from Geo-eye 1 imagery using visual interpretation technique. Landsat image of the Data used for the interpretation of the landform, the classification of the slopes obtained from high point identification with method of interpolation spline, whereas climate data, soil, use secondary data originating from institutions-related institutions. The results of this research indicate Tegallalang and Payangan Districts in known wetland suitability consists of S1 (very suitable) covering an area of 2884,7 ha with the productivity of 5 tons/ha and S2 (suitable) covering an area of 482,9 ha with the productivity of 3 tons/ha. The sum of paddy production estimation as a results in both districts are 31.744, 3 tons in one year.

Keywords: production estimation, paddy, remote sensing, geography information system, land suitability

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3285 Plant Growth and Yield Enhancement of Soybean by Inoculation with Symbiotic and Nonsymbiotic Bacteria

Authors: Timea I. Hajnal-Jafari, Simonida S. Đurić, Dragana R. Stamenov

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Microbial inoculants from the group of symbiotic-nitrogen-fixing rhizobia are well known and widely used in production of legumes. On the other hand, nonsymbiotic plant growth promoting rhizobacteria (PGPR) are not commonly used in practice. The objective of this study was to examine the effects of soybean inoculation with symbiotic and nonsymbiotic bacteria on plant growth and seed yield of soybean. Microbiological activity in rhizospheric soil was also determined. The experiment was set up using a randomized block system in filed conditions with the following treatments: control-no inoculation; treatment 1-Bradyrhizobium japonicum; treatment 2-Azotobacter sp.; treatment 3-Bacillus sp..In the flowering stage of growth (FS) the number of nodules per plant (NPP), root length (RL), plant height (PH) and weight (PW) were measured. The number of pod per plant (PPP), number of seeds per pod (SPP) and seed weight per plant (SWP) were recorded at the end of vegetation period (EV). Microbiological analyses of soil included the determination of total number of bacteria (TNB), number of fungi (FNG), actinomycetes (ACT) and azotobacters (AZB) as well as the activity of the dehydrogenase enzyme (DHA). The results showed that bacterial inoculation led to the formation of root nodules regardless of the treatments with statistically no significant difference. Strong nodulation was also present in control treatment. RL and PH were positively influenced by inoculation with Azotobacter sp. and Bacillus sp., respectively. Statistical analyses of the number of PPP, SPP, and SWP showed no significant differences among investigated treatments. High average number of microorganisms were determined in all treatments. Most abundant were TNB (log No 8,010) and ACT (log No 6,055) than FNG and AZB with log No 4,867 and log No 4,025, respectively. The highest DHA activity was measured in the FS of soybean in treatment 3. The application of nonsymbiotic bacteria in soybean production can alleviate initial plant growth and help the plant to better overcome different stress conditions caused by abiotic and biotic factors.

Keywords: bacteria, inoculation, soybean, microbial activity

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3284 The Evaluation for Interfacial Adhesion between SOFC and Metal Adhesive in the High Temperature Environment

Authors: Sang Koo Jeon, Seung Hoon Nahm, Oh Heon Kwon

Abstract:

The unit cell of solid oxide fuel cell (SOFC) must be stacked as several layers type to obtain the high power. The most of researcher have concerned about the performance of stacked SOFC rather than the structural stability of stacked SOFC and especially interested how to design for reducing the electrical loss and improving the high efficiency. Consequently, the stacked SOFC able to produce the electrical high power and related parts like as manifold, gas seal, bipolar plate were developed to optimize the stack design. However, the unit cell of SOFC was just layered on the interconnector without the adhesion and the hydrogen and oxygen were injected to the interfacial layer in the high temperature. On the operating condition, the interfacial layer can be the one of the weak point in the stacked SOFC. Therefore the evaluation of the structural safety for the failure is essentially needed. In this study, interfacial adhesion between SOFC and metal adhesive was estimated in the high temperature environment. The metal adhesive was used to strongly connect the unit cell of SOFC with interconnector and provide the electrical conductivity between them. The four point bending test was performed to measure the interfacial adhesion. The unit cell of SOFC and SiO2 wafer were diced and then attached by metal adhesive. The SiO2 wafer had the center notch to initiate a crack from the tip of the notch. The modified stereomicroscope combined with the CCD camera and system for measuring the length was used to observe the fracture behavior. Additionally, the interfacial adhesion was evaluated in the high temperature condition because the metal adhesive was affected by high temperature. Also the specimen was exposed in the furnace during several hours and then the interfacial adhesion was evaluated. Finally, the interfacial adhesion energy was quantitatively determined and compared in the each condition.

Keywords: solid oxide fuel cell (SOFC), metal adhesive, adhesion, high temperature

Procedia PDF Downloads 521
3283 The Minimum Age of Criminal Responsibility in the Philippines: Balancing International Standards and Domestic Concerns

Authors: Harold P. Pareja

Abstract:

This paper answers the question whether the minimum age of criminal responsibility under the Republic Act No. 9344 (Juvenile Justice Act) as amended by Republic Act No. 10630 should be lowered to 15 years of age or not in the light of international standards and domestic concerns both of which will definitely elicit strong views. It also explores the specific provision on the minimum age of criminal responsibility under the Republic Act No. 9344 (Juvenile Justice Act) and traces the bases of such law by discussing its presented evidences and justifications as reflected in the records of proceedings in the law-making phase. On one hand, the paper discusses the impact of lowering the minimum age to the state of juvenile delinquencies and to the rate of rehabilitation for those CICL who have undergone the DSWD-supervised recovery programs. On the other hand, it presents its impact to the international community specifically to the Committee of the Rights of the Child and the UNICEF considering that the even the current minimum age set in RA 9344 is lower than the international standards. Document review and content analysis are the major research tools. Primary and secondary sources were used as references such as Philippine laws on juvenile justice and from the different states international think-tanks. The absence of reliable evidences on criminal capacity made the arguments in increasing the MACR in the harder position. Studies on criminal capacity vary from different countries and from practitioners in in the fields of psychology, psychiatry and forensics. Juvenile delinquency is mainly contributed by poverty and dysfunctional families. On the other hand, the science of the criminal mind specifically among children has not been established yet. Philippines have the legal obligations to be faithful to the CRC and other related international instruments for the juvenile justice and welfare system. Decreasing MACR does not only send wrong message to the international community but the Philippines is violating its own laws.

Keywords: juvenile justice, minimum age of responsibility (MAR), juvenile justice act of the Philippines, children in conflict with the law, international standards on juvenile justice

Procedia PDF Downloads 411
3282 A Comparative Study of Cognitive Functions in Relapsing-Remitting Multiple Sclerosis Patients, Secondary-Progressive Multiple Sclerosis Patients and Normal People

Authors: Alireza Pirkhaefi

Abstract:

Background: Multiple sclerosis (MS) is one of the most common diseases of the central nervous system (brain and spinal cord). Given the importance of cognitive disorders in patients with multiple sclerosis, the present study was in order to compare cognitive functions (Working memory, Attention and Centralization, and Visual-spatial perception) in patients with relapsing- remitting multiple sclerosis (RRMS) and secondary progressive multiple sclerosis (SPMS). Method: Present study was performed as a retrospective study. This research was conducted with Ex-Post Facto method. The samples of research consisted of 60 patients with multiple sclerosis (30 patients relapsing-retrograde and 30 patients secondary progressive), who were selected from Tehran Community of MS Patients Supported as convenience sampling. 30 normal persons were also selected as a comparison group. Montreal Cognitive Assessment (MOCA) was used to assess cognitive functions. Data were analyzed using multivariate analysis of variance. Results: The results showed that there were significant differences among cognitive functioning in patients with RRMS, SPMS, and normal individuals. There were not significant differences in working memory between two groups of patients with RRMS and SPMS; while significant differences in these variables were seen between the two groups and normal individuals. Also, results showed significant differences in attention and centralization and visual-spatial perception among three groups. Conclusions: Results showed that there are differences between cognitive functions of RRMS and SPMS patients so that the functions of RRMS patients are better than SPMS patients. These results have a critical role in improvement of cognitive functions; reduce the factors causing disability due to cognitive impairment, and especially overall health of society.

Keywords: multiple sclerosis, cognitive function, secondary-progressive, normal subjects

Procedia PDF Downloads 240
3281 Analysis of Underground Logistics Transportation Technology and Planning Research: Based on Xiong'an New Area, China

Authors: Xia Luo, Cheng Zeng

Abstract:

Under the promotion of the Central Committee of the Communist Party of China and the State Council in 2017, Xiong'an New Area is the third crucial new area in China established after Shenzhen and Shanghai. Its constructions' significance lies in mitigating Beijing's non-capital functions and exploring a new mode of optimizing development in densely populated and economically intensive areas. For this purpose, developing underground logistics can assume the role of goods distribution in the capital, relieve the road transport pressure in Beijing-Tianjin-Hebei Urban Agglomeration, adjust and optimize the urban layout and spatial structure of it. Firstly, the construction planning of Xiong'an New Area and underground logistics development are summarized, especially the development status abroad, the development trend, and bottlenecks of underground logistics in China. This paper explores the technicality, feasibility, and necessity of four modes of transportation. There are pneumatic capsule pipeline (PCP) technology, the CargoCap technology, cable hauled mule, and automatic guided vehicle (AGV). The above technical parameters and characteristics are introduced to relevant experts or scholars. Through establishing an indicator system, carrying out a questionnaire survey with the Delphi method, the final suggestion is obtained: China should develop logistics vehicles similar to CargoCap, adopting rail mode and driverless mode. Based on China's temporal and spatial logistics demand and the geographical pattern of Xiong'an New Area, the construction scale, technical parameters, node location, and other vital parameters of underground logistics are planned. In this way, we hope to speed up the new area's construction and the logistics industry's innovation.

Keywords: the Xiong'an new area, underground logistics, contrastive analysis, CargoCap, logistics planning

Procedia PDF Downloads 131
3280 E-Book Market In Vietnam: Great Potential, Many Barriers

Authors: Zakir Hossain

Abstract:

Nowadays reading e-books on laptops, smartphones, and tablets have become a new leisure activity for Vietnamese youth. Since 2011 the copyrighted e-book market began to develop in Vietnam with the participation of five local enterprises. Over the last five years, thousands of e-books were published including the first online early education book series for children from 0 to 6 years old. Research shows that 61% Vietnamese find reading e-books is comfortable, and 45% feel convenient buying books online. More than half of the Vietnamese consider reading online far better than buying printed books, and surprisingly people over age 30 desire reading online while those under 18 prefer reading printed books. Hence with a market of more than 40 million regular internet users including 22 million smartphone users, Vietnam has ample opportunities to develop the e-book market and contribute a great deal to the diversity of the local reading culture which is essential for Building a Lifelong Learning Society, a state ambition of Vietnam by 2020. However, the e-book market in Vietnam is still in its infancy and is growing far too slowly than e-book producers had expected. All five e-book enterprises are facing numerous challenges. While the big profit that e-book technology can bring has been clearly recognised in other countries, e-books in Vietnam only make up less than 1% share of the book market. The objective of the study is to identify the difficulties and barriers to the development of the e-book market in Vietnam through an extensive literature review available in English. The study revealed that illegal e-books due to copyright infringement and an inconvenient payment system to purchase e-books are the major obstacles. The great potential of e-books in Vietnam is a reality but requires government enforcement of copyright protection laws, a new area of focus for the e-book market. Furthermore, Vietnamese readers should change their habits from using free and illegal e-books to develop the e-publishing industry in Vietnam.

Keywords: copyright, e-book, e-book reading, e-publishing, Vietnam

Procedia PDF Downloads 229
3279 Oil Water Treatment by Nutshell and Dates Pits

Authors: Abdalrahman D. Alsulaili, Sheikha Y. Aljeraiwi, Athba N. Almanaie, Raghad Y. Alhajeri, Mariam Z. Almijren

Abstract:

The water accompanying oil in the oil production process is increasing and due to its increasing rates a problem with handling it occurred. Current solutions like discharging into the environment, dumping water in evaporation pits, usage in the industry and reinjection in oil reservoirs to enhance oil production are used worldwide. The water injection method has been introduced to the oil industry with a process that either immediately injects water to the reservoir or goes to the filtration process before injection all depending on the porosity of the soil. Reinjection of unfiltered effluent water with high Total Suspended Solid (TSS) and Oil in Water (O/W) into soils with low porosity cause a blockage of pores, whereas soils with high porosity do not need high water quality. Our study mainly talks about the filtration and adsorption of the water using organic media as the adsorbent. An adsorbent is a substance that has the ability to physically hold another substance in its surface. Studies were done on nutshell and date pits with different surface areas and flow rates by using a 10inch filter connected with three tanks to perform as one system for the filtration process. Our approach in the filtration process using different types of medias went as follow: starting first with crushed nutshell, second with ground nutshell, and third using carbonized date pits with medium flow rate then high flow rate to compare different results. The result came out nearly as expected from our study where both O/W and TSS were reduced from our oily water sample by using this organic material. The effect of specific area was noticed when using nutshell as the filter media, where the crushed nutshell gave us better results than ground nutshell. The effect of flow rate was noticed when using carbonized date pits as the filter media whereas the treated water became more acceptable when the flow rate was on the medium level.

Keywords: date pits, nutshell, oil water, TSS

Procedia PDF Downloads 158
3278 Effects of Climate Change on Floods of Pakistan, and Gap Analysis of Existing Policies with Vision 2025

Authors: Saima Akbar, Tahseen Ullah Khan

Abstract:

The analysis of the climate change impact on flood frequency represents an important issue for water resource management and flood risk mitigation. This research was conducted to address the effects of climate change on flood incidents of Pakistan and find out gaps in existing policies to reducing the environmental aspects on floods and effects of global warming. The main objective of this research was to critically analyses the National Climate Change Policy (NCCP), National Disaster Management Authority (NDMA), Federal Flood Commission (FFC) and Vision 2025, as an effective policy document which is not only hitting the target of a climate resilient Pakistan but provides room for efficient and flexible policy implementation. The methodology integrates projected changes in monsoon patterns (since last 20 years and overall change in rainfall pattern since 1901 to 2015 from Pakistan Metrological Department), glacier melting, decreasing dam capacity and lacks in existing policies by using SWOT (Strength, Weakness, Opportunities, Threats) model in order to explore the relative impacts of global warming on the system performance. Results indicate the impacts of climate change are significant, but probably not large enough to justify a major effort for adapting the physical infrastructure to expected climatic conditions in Vision 2025 which is our shared destination to progress, ultimate aspiration to see Pakistan among the ten largest economies of the world by 2047– the centennial year of our independence. The conclusion of this research was to adapt sustainable measures to reduce flood impacts and make policies as neighboring countries are adapting for their sustainability.

Keywords: climatic factors, monsoon, Pakistan, sustainability

Procedia PDF Downloads 142
3277 Application of Life Cycle Assessment “LCA” Approach for a Sustainable Building Design under Specific Climate Conditions

Authors: Djeffal Asma, Zemmouri Noureddine

Abstract:

In order for building designer to be able to balance environmental concerns with other performance requirements, they need clear and concise information. For certain decisions during the design process, qualitative guidance, such as design checklists or guidelines information may not be sufficient for evaluating the environmental benefits between different building materials, products and designs. In this case, quantitative information, such as that generated through a life cycle assessment, provides the most value. LCA provides a systematic approach to evaluating the environmental impacts of a product or system over its entire life. In the case of buildings life cycle includes the extraction of raw materials, manufacturing, transporting and installing building components or products, operating and maintaining the building. By integrating LCA into building design process, designers can evaluate the life cycle impacts of building design, materials, components and systems and choose the combinations that reduce the building life cycle environmental impact. This article attempts to give an overview of the integration of LCA methodology in the context of building design, and focuses on the use of this methodology for environmental considerations concerning process design and optimization. A multiple case study was conducted in order to assess the benefits of the LCA as a decision making aid tool during the first stages of the building design under specific climate conditions of the North East region of Algeria. It is clear that the LCA methodology can help to assess and reduce the impact of a building design and components on the environment even if the process implementation is rather long and complicated and lacks of global approach including human factors. It is also demonstrated that using LCA as a multi objective optimization of building process will certainly facilitates the improvement in design and decision making for both new design and retrofit projects.

Keywords: life cycle assessment, buildings, sustainability, elementary schools, environmental impacts

Procedia PDF Downloads 548
3276 TutorBot+: Automatic Programming Assistant with Positive Feedback based on LLMs

Authors: Claudia Martínez-Araneda, Mariella Gutiérrez, Pedro Gómez, Diego Maldonado, Alejandra Segura, Christian Vidal-Castro

Abstract:

The purpose of this document is to showcase the preliminary work in developing an EduChatbot-type tool and measuring the effects of its use aimed at providing effective feedback to students in programming courses. This bot, hereinafter referred to as tutorBot+, was constructed based on chatGPT and is tasked with assisting and delivering timely positive feedback to students in the field of computer science at the Universidad Católica de Concepción. The proposed working method consists of four stages: (1) Immersion in the domain of Large Language Models (LLMs), (2) Development of the tutorBot+ prototype and integration, (3) Experiment design, and (4) Intervention. The first stage involves a literature review on the use of artificial intelligence in education and the evaluation of intelligent tutors, as well as research on types of feedback for learning and the domain of chatGPT. The second stage encompasses the development of tutorBot+, and the final stage involves a quasi-experimental study with students from the Programming and Database labs, where the learning outcome involves the development of computational thinking skills, enabling the use and measurement of the tool's effects. The preliminary results of this work are promising, as a functional chatBot prototype has been developed in both conversational and non-conversational versions integrated into an open-source online judge and programming contest platform system. There is also an exploration of the possibility of generating a custom model based on a pre-trained one tailored to the domain of programming. This includes the integration of the created tool and the design of the experiment to measure its utility.

Keywords: assessment, chatGPT, learning strategies, LLMs, timely feedback

Procedia PDF Downloads 71
3275 Lexical Based Method for Opinion Detection on Tripadvisor Collection

Authors: Faiza Belbachir, Thibault Schienhinski

Abstract:

The massive development of online social networks allows users to post and share their opinions on various topics. With this huge volume of opinion, it is interesting to extract and interpret these information for different domains, e.g., product and service benchmarking, politic, system of recommendation. This is why opinion detection is one of the most important research tasks. It consists on differentiating between opinion data and factual data. The difficulty of this task is to determine an approach which returns opinionated document. Generally, there are two approaches used for opinion detection i.e. Lexical based approaches and Machine Learning based approaches. In Lexical based approaches, a dictionary of sentimental words is used, words are associated with weights. The opinion score of document is derived by the occurrence of words from this dictionary. In Machine learning approaches, usually a classifier is trained using a set of annotated document containing sentiment, and features such as n-grams of words, part-of-speech tags, and logical forms. Majority of these works are based on documents text to determine opinion score but dont take into account if these texts are really correct. Thus, it is interesting to exploit other information to improve opinion detection. In our work, we will develop a new way to consider the opinion score. We introduce the notion of trust score. We determine opinionated documents but also if these opinions are really trustable information in relation with topics. For that we use lexical SentiWordNet to calculate opinion and trust scores, we compute different features about users like (numbers of their comments, numbers of their useful comments, Average useful review). After that, we combine opinion score and trust score to obtain a final score. We applied our method to detect trust opinions in TRIPADVISOR collection. Our experimental results report that the combination between opinion score and trust score improves opinion detection.

Keywords: Tripadvisor, opinion detection, SentiWordNet, trust score

Procedia PDF Downloads 201
3274 Assessment of Hepatosteatosis Among Diabetic and Nondiabetic Patients Using Biochemical Parameters and Noninvasive Imaging Techniques

Authors: Tugba Sevinc Gamsiz, Emine Koroglu, Ozcan Keskin

Abstract:

Aim: Nonalcoholic fatty liver disease (NAFLD) is considered the most common chronic liver disease in the general population. The higher mortality and morbidity among NAFLD patients and lack of symptoms makes early detection and management important. In our study, we aimed to evaluate the relationship between noninvasive imaging and biochemical markers in diabetic and nondiabetic patients diagnosed with NAFLD. Materials and Methods: The study was conducted from (September 2017) to (December 2017) on adults admitted to Internal Medicine and Gastroenterology outpatient clinics with hepatic steatosis reported on ultrasound or transient elastography within the last six months that exclude patients with other liver diseases or alcohol abuse. The data were collected and analyzed retrospectively. Number cruncher statistical system (NCSS) 2007 program was used for statistical analysis. Results: 116 patients were included in this study. Diabetic patients compared to nondiabetics had significantly higher Controlled Attenuation Parameter (CAP), Liver Stiffness Measurement (LSM) and fibrosis values. Also, hypertension, hepatomegaly, high BMI, hypertriglyceridemia, hyperglycemia, high A1c, and hyperuricemia were found to be risk factors for NAFLD progression to fibrosis. Advanced fibrosis (F3, F4) was present in 18,6 % of all our patients; 35,8 % of diabetic and 5,7 % of nondiabetic patients diagnosed with hepatic steatosis. Conclusion: Transient elastography is now used in daily clinical practice as an accurate noninvasive tool during follow-up of patients with fatty liver. Early diagnosis of the stage of liver fibrosis improves the monitoring and management of patients, especially in those with metabolic syndrome criteria.

Keywords: diabetes, elastography, fatty liver, fibrosis, metabolic syndrome

Procedia PDF Downloads 154
3273 Optimization of Doubly Fed Induction Generator Equivalent Circuit Parameters by Direct Search Method

Authors: Mamidi Ramakrishna Rao

Abstract:

Doubly-fed induction generator (DFIG) is currently the choice for many wind turbines. These generators, when connected to the grid through a converter, is subjected to varied power system conditions like voltage variation, frequency variation, short circuit fault conditions, etc. Further, many countries like Canada, Germany, UK, Scotland, etc. have distinct grid codes relating to wind turbines. Accordingly, following the network faults, wind turbines have to supply a definite reactive current. To satisfy the requirements including reactive current capability, an optimum electrical design becomes a mandate for DFIG to function. This paper intends to optimize the equivalent circuit parameters of an electrical design for satisfactory DFIG performance. Direct search method has been used for optimization of the parameters. The variables selected include electromagnetic core dimensions (diameters and stack length), slot dimensions, radial air gap between stator and rotor and winding copper cross section area. Optimization for 2 MW DFIG has been executed separately for three objective functions - maximum reactive power capability (Case I), maximum efficiency (Case II) and minimum weight (Case III). In the optimization analysis program, voltage variations (10%), power factor- leading and lagging (0.95), speeds for corresponding to slips (-0.3 to +0.3) have been considered. The optimum designs obtained for objective functions were compared. It can be concluded that direct search method of optimization helps in determining an optimum electrical design for each objective function like efficiency or reactive power capability or weight minimization.

Keywords: direct search, DFIG, equivalent circuit parameters, optimization

Procedia PDF Downloads 257