Search results for: genetic testing
Commenced in January 2007
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Edition: International
Paper Count: 4402

Search results for: genetic testing

1282 Role of Maternal Astaxanthin Supplementation on Brain Derived Neurotrophic Factor and Spatial Learning Behavior in Wistar Rat Offspring’s

Authors: K. M. Damodara Gowda

Abstract:

Background: Maternal health and nutrition are considered as the predominant factors influencing brain functional development. If the mother is free of illness and genetic defects, maternal nutrition would be one of the most critical factors affecting the brain development. Calorie restrictions cause significant impairment in spatial learning ability and the levels of Brain Derived Neurotrophic Factor (BDNF) in rats. But, the mechanism by which the prenatal under-nutrition leads to impairment in brain learning and memory function is still unclear. In the present study, prenatal Astaxanthin supplementation on BDNF level, spatial learning and memory performance in the offspring’s of normal, calorie restricted and Astaxanthin supplemented rats was investigated. Methodology: The rats were administered with 6mg and 12 mg of astaxanthin /kg bw for 21 days following which acquisition and retention of spatial memory was tested in a partially-baited eight arm radial maze. The BDNF level in different regions of the brain (cerebral cortex, hippocampus and cerebellum) was estimated by ELISA method. Results: Calorie restricted animals treated with astaxanthin made significantly more correct choices (P < 0.05), and fewer reference memory errors (P < 0.05) on the tenth day of training compared to offsprings of calorie restricted animals. Calorie restricted animals treated with astaxanthin also made significantly higher correct choices (P < 0.001) than untreated calorie restricted animals in a retention test 10 days after the training period. The mean BDNF level in cerebral cortex, Hippocampus and cerebellum in Calorie restricted animals treated with astaxanthin didnot show significant variation from that of control animals. Conclusion: Findings of the study indicated that memory and learning was impaired in the offspring’s of calorie restricted rats which was effectively modulated by astaxanthin at the dosage of 12 mg/kg body weight. In the same way the BDNF level at cerebral cortex, Hippocampus and Cerebellum was also declined in the offspring’s of calorie restricted animals, which was also found to be effectively normalized by astaxanthin.

Keywords: calorie restiction, learning, Memory, Cerebral cortex, Hippocampus, Cerebellum, BDNF, Astaxanthin

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1281 Therapeutic Effects of Guar Gum Nanoparticles in Oxazolone-Induced Atopic Dermatitis

Authors: Nandita Ghosh, Shinjini Mitra, Ena Ray Banerjee

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Atopic dermatitis (AD) is a chronic disease of the skin, involving itchy, reddish, and scaly lesions. It mainly affects children and has a high prevalence in developing countries. The AD may occur due to environmental or genetic factors. There is no permanent cure for the AD. Currently, all therapeutic strategies involve methods to simply alleviate the symptoms, and include lotions and corticosteroids, which have adverse effects. Use of phytochemicals and natural products has not yet been exploited fully. The particle used in this study is derived from Cyamopsis tetragonoloba, an edible polysaccharide with a galactomannan component. The mannose component mainly increases its specificity towards cellular uptake by mannose receptors, highly expressed by the macrophage. The aim of this study was to determine the therapeutic effect of guar gum nanoparticles (GN) in vitro and in vivo in the AD. To assess the wound healing capacity of the guar gum nanoparticle (GN), we first treated adherent NIH3T3 cells, with a scratch injury, with GN. GN successfully healed the wound caused by the scratch. In the in vivo experiment, Balb/c mice ear were topically treated with oxazolone (oxa) to induce AD and then were topically treated with GN. The ear thickness was increased significantly till day 28 on the treatment of Oxa. The GN application showed a significant decrease in the thickness as assessed on day 28. The total cell count of skin cells showed fold increase when treated with oxa, was again decreased on topical application of GN on the affected skin. The eosinophil count, as assessed by Giemsa staining was also increased when treated with oxa, GN application led to a significant decrease. The IgE level was assessed in the serum samples which showed that GN helped in restoring the alleviated IgE level. The T helper cells and the macrophage population showed increased percentage when treated with oxa, the GN application. This was examined by flow cytometry. The H&E staining of the ear tissue showed epidermal thickness in the oxa treated mice, GN application showed reduced cellular filtration followed by epidermal thickness. Thus our assays showed that GN was successful in alleviating the disease caused by Oxa when administered topically.

Keywords: allergen, inflammation, nanodrug, wound

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1280 Influence of Humidity on Environmental Sustainability, Air Quality and Occupant Health

Authors: E. Cintura, M. I. Gomes

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Nowadays, sustainable development issues have a key role in the planning of the man-made environment. Ensuring this development means limiting the impact of human activity on nature. It is essential to secure healthy places and good living conditions. For these reasons, indoor air quality and building materials play a fundamental role in sustainable architectural projects. These factors significantly affect human health: they can radically change the quality of the internal environment and energy consumption. The use of natural materials such as earth has many beneficial aspects in comfort and indoor air quality. As well as advantages in the environmental impact of the construction, they ensure a low energy consumption. Since they are already present in nature, their production and use do not require a high-energy consumption. Furthermore, they have a high thermo-hygrometric capacity, being able to absorb moisture, contributing positively to indoor conditions. Indoor air quality is closely related to relative humidity. For these reasons, it can be affirmed that the use of earth materials guarantees a sustainable development and at the same time improves the health of the building users. This paper summarizes several researches that demonstrate the importance of indoor air quality for human health and how it strictly depends on the building materials used. Eco-efficient plasters are also considered: earth and ash mortar. The bibliography consulted has the objective of supporting future experimental and laboratory analyzes. It is necessary to carry on with research by the use of simulations and testing to confirm the hygrothermal properties of eco-efficient plasters and therefore their ability to improve indoor air quality.

Keywords: hygroscopicity, hygrothermal comfort, mortar, plaster

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1279 Biological Control of Fusarium Crown and Root and Tomato (Solanum lycopersicum L.) Growth Promotion Using Endophytic Fungi from Withania somnifera L.

Authors: Nefzi Ahlem, Aydi Ben Abdallah Rania, Jabnoun-Khiareddine Hayfa, Ammar Nawaim, Mejda Daami-Remadi

Abstract:

Fusarium Crown and Root Rot (FCRR) caused by Fusarium oxysporum f. sp. radicis-lycopersici (FORL) is a serious tomato (Solanum lycopersicum L.) disease in Tunisia. Its management is very difficult due to the long survival of its resting structures and to the luck of genetic resistance. In this work, we explored the wild Solanaceae species Withania somnifera, growing in the Tunisian Centre-East, as a potential source of biocontrol agents effective in FCRR suppression and tomato growth promotion. Seven fungal isolates were shown able to colonize tomato roots, crowns, and stems. Used as conidial suspensions or cell-free culture filtrates, all tested fungal treatments significantly enhanced tomato growth parameters by 21.5-90.3% over FORL-free control and by 27.6-93.5% over pathogen-inoculated control. All treatments significantly decreased the leaf and root damage index by 28.5-92.8 and the vascular browning extent 9.7-86.4% over FORL-inoculated and untreated control. The highest disease suppression ability (decrease by 86.4-92.8% in FCRR severity) over pathogen-inoculated control and by 81.3-88.8 over hymexazol-treated control) was expressed by I6 based treatments. This endophytic fungus was morphologically characterized and identified using rDNA sequencing gene as Fusarium sp. I6 (MG835371). This fungus was shown able to reduce FORL radial growth by 58.5–83.2% using its conidial suspension or cell-free culture filtrate. Fusarium sp. I6 showed chitinolytic, proteolytic and amylase activities. The current study clearly demonstrated that Fusarium sp. (I6) is a promising biocontrol candidate for suppressing FCRR severity and promoting tomato growth. Further investigations are required for elucidating its mechanism of action involved in disease suppression and plant growth promotion.

Keywords: antifungal activity, associated fungi, Fusarium oxysporum f. sp. radicis-lycopersici, Withania somnifera, tomato growth

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1278 Hidden Populations and Women: New Political, Methodological and Ethical Challenges

Authors: Renée Fregosi

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The contribution presently proposed will report on the beginnings of a Franco-Chilean study to be launched in 2015 by a multidisciplinary team of Renée Fregosi Political Science University Paris 3 / CECIEC, Norma Muñoz Public Policies University of Santiago of Chile, Jean-Daniel Lelievre, Medicine Paris 11 University, Marcelo WOLFF Medicine University of Chile, Cecilia Blatrix Political Science University Paris-Tech, Ernesto OTTONE, Political Science University of Chile, Paul DENY Medicine Paris 13 University, Rafael Bugueno Medicine Hospital Urgencia Pública of Santiago, Eduardo CARRASCO Political Science Paris 3 University. The problem of hidden populations challenges some criteria and concepts to re-examine: in particular the concept of target population, sampling methods to "snowball" and the cost-effectiveness criterion that shows the connection of political and scientific fields. Furthermore, if the pattern of homosexual transmission still makes up the highest percentage of the modes of infection with HIV, there is a continuous increase in the number of people infected through heterosexual sex, including women and persons aged 50 years and older. This group can be described as " unknown risk people." Access to these populations is a major challenge and raises methodological, ethical and political issues of prevention, particularly on the issue of screening. This paper proposes an inventory of these types of problems and their articulation, to define a new phase in the prevention against HIV refocused on women.

Keywords: HIV testing, hidden populations, difficult to reach PLWHA, women, unknown risk people

Procedia PDF Downloads 500
1277 Expression Profiling and Immunohistochemical Analysis of Squamous Cell Carcinoma of Head and Neck (Tumor, Transition Zone, Normal) by Whole Genome Scale Sequencing

Authors: Veronika Zivicova, Petr Broz, Zdenek Fik, Alzbeta Mifkova, Jan Plzak, Zdenek Cada, Herbert Kaltner, Jana Fialova Kucerova, Hans-Joachim Gabius, Karel Smetana Jr.

Abstract:

The possibility to determine genome-wide expression profiles of cells and tissues opens a new level of analysis in the quest to define dysregulation in malignancy and thus identify new tumor markers. Toward this long-term aim, we here address two issues on this level for head and neck cancer specimen: i) defining profiles in different regions, i.e. the tumor, the transition zone and normal control and ii) comparing complete data sets for seven individual patients. Special focus in the flanking immunohistochemical part is given to adhesion/growth-regulatory galectins that upregulate chemo- and cytokine expression in an NF-κB-dependent manner, to these regulators and to markers of differentiation, i.e. keratins. The detailed listing of up- and down-regulations, also available in printed form (1), not only served to unveil new candidates for testing as marker but also let the impact of the tumor in the transition zone become apparent. The extent of interindividual variation raises a strong cautionary note on assuming uniformity of regulatory events, to be noted when considering therapeutic implications. Thus, a combination of test targets (and a network analysis for galectins and their downstream effectors) is (are) advised prior to reaching conclusions on further perspectives.

Keywords: galectins, genome scale sequencing, squamous cell carcinoma, transition zone

Procedia PDF Downloads 219
1276 A Programming Assessment Software Artefact Enhanced with the Help of Learners

Authors: Romeo A. Botes, Imelda Smit

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The demands of an ever changing and complex higher education environment, along with the profile of modern learners challenge current approaches to assessment and feedback. More learners enter the education system every year. The younger generation expects immediate feedback. At the same time, feedback should be meaningful. The assessment of practical activities in programming poses a particular problem, since both lecturers and learners in the information and computer science discipline acknowledge that paper-based assessment for programming subjects lacks meaningful real-life testing. At the same time, feedback lacks promptness, consistency, comprehensiveness and individualisation. Most of these aspects may be addressed by modern, technology-assisted assessment. The focus of this paper is the continuous development of an artefact that is used to assist the lecturer in the assessment and feedback of practical programming activities in a senior database programming class. The artefact was developed using three Design Science Research cycles. The first implementation allowed one programming activity submission per assessment intervention. This pilot provided valuable insight into the obstacles regarding the implementation of this type of assessment tool. A second implementation improved the initial version to allow multiple programming activity submissions per assessment. The focus of this version is on providing scaffold feedback to the learner – allowing improvement with each subsequent submission. It also has a built-in capability to provide the lecturer with information regarding the key problem areas of each assessment intervention.

Keywords: programming, computer-aided assessment, technology-assisted assessment, programming assessment software, design science research, mixed-method

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1275 Internet of Things Networks: Denial of Service Detection in Constrained Application Protocol Using Machine Learning Algorithm

Authors: Adamu Abdullahi, On Francisca, Saidu Isah Rambo, G. N. Obunadike, D. T. Chinyio

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The paper discusses the potential threat of Denial of Service (DoS) attacks in the Internet of Things (IoT) networks on constrained application protocols (CoAP). As billions of IoT devices are expected to be connected to the internet in the coming years, the security of these devices is vulnerable to attacks, disrupting their functioning. This research aims to tackle this issue by applying mixed methods of qualitative and quantitative for feature selection, extraction, and cluster algorithms to detect DoS attacks in the Constrained Application Protocol (CoAP) using the Machine Learning Algorithm (MLA). The main objective of the research is to enhance the security scheme for CoAP in the IoT environment by analyzing the nature of DoS attacks and identifying a new set of features for detecting them in the IoT network environment. The aim is to demonstrate the effectiveness of the MLA in detecting DoS attacks and compare it with conventional intrusion detection systems for securing the CoAP in the IoT environment. Findings: The research identifies the appropriate node to detect DoS attacks in the IoT network environment and demonstrates how to detect the attacks through the MLA. The accuracy detection in both classification and network simulation environments shows that the k-means algorithm scored the highest percentage in the training and testing of the evaluation. The network simulation platform also achieved the highest percentage of 99.93% in overall accuracy. This work reviews conventional intrusion detection systems for securing the CoAP in the IoT environment. The DoS security issues associated with the CoAP are discussed.

Keywords: algorithm, CoAP, DoS, IoT, machine learning

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1274 Physical Fitness Evaluation of Physical Education Teachers in Maktab Rendah Sains MARA (MRSM)

Authors: Mohamad Nizam Asmuni, Ahmad Naszeri Salleh, Yunus Adam, Azhar Yaacob, Mohd Hafiz Rosli, Muhamad Nazrul Hakim Abdullah

Abstract:

Physical Education teacher at the school should have good physical fitness to educate and guide students in the school. Currently, there are no standards for the level of physical fitness for teachers who teaches physical education at the school. Therefore, this research is to determine the level of physical fitness of teacher of Physical Education at Maktab Rendah Sains MARA (MRSM). A total of 28 samples (18 men and 10 women, age 33 ± 4.91), teachers of physical education at MRSM, were randomly selected to participate in this study. Height, weight, body fat percentage, body mass index (BMI) and other physical testing are measured and recorded. The results showed that the average of body mass index (BMI) for teachers of Physical Education is 25.9 ± 4:57. Body mass index (BMI) of teachers can be categorized as pre-obese based on World Health Organization (WHO) guidelines. Body fat percentage for male (age; 34.3 ± 5.13) and female (age; 30.9 ± 3.81) teachers is 24.7% ± 6.54 and 30.6% ± 6.28, respectively. Male teachers were categorized as overfat, however, female teachers were categorized as healthy based on body fat ranges for standard adults at NY Obesity Research Center. Bleep test results show that the average Bleep test is level 4 and shuttle 2; average VO2max was 27.5 ± 5.94 L/min. Physical fitness and performance of physical education teachers at MRSM is much lower compared to the rugby junior athlete in University Putra Malaysia (UPM). Therefore, physical fitness of teachers must be improved to ensure the physical education classes at MRSM could be done better.

Keywords: physical fitness, BMI, bleep test, obesity

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1273 Using Data Mining in Automotive Safety

Authors: Carine Cridelich, Pablo Juesas Cano, Emmanuel Ramasso, Noureddine Zerhouni, Bernd Weiler

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Safety is one of the most important considerations when buying a new car. While active safety aims at avoiding accidents, passive safety systems such as airbags and seat belts protect the occupant in case of an accident. In addition to legal regulations, organizations like Euro NCAP provide consumers with an independent assessment of the safety performance of cars and drive the development of safety systems in automobile industry. Those ratings are mainly based on injury assessment reference values derived from physical parameters measured in dummies during a car crash test. The components and sub-systems of a safety system are designed to achieve the required restraint performance. Sled tests and other types of tests are then carried out by car makers and their suppliers to confirm the protection level of the safety system. A Knowledge Discovery in Databases (KDD) process is proposed in order to minimize the number of tests. The KDD process is based on the data emerging from sled tests according to Euro NCAP specifications. About 30 parameters of the passive safety systems from different data sources (crash data, dummy protocol) are first analysed together with experts opinions. A procedure is proposed to manage missing data and validated on real data sets. Finally, a procedure is developed to estimate a set of rough initial parameters of the passive system before testing aiming at reducing the number of tests.

Keywords: KDD process, passive safety systems, sled test, dummy injury assessment reference values, frontal impact

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1272 Aerobic Capacity Outcomes after an Aerobic Exercise Program with an Upper Body Ergometer in Diabetic Amputees

Authors: Cecilia Estela Jiménez Pérez Campos

Abstract:

Introduction: Amputation comes from a series of complications in diabetic persons; at that point, of the illness evolution they have a deplored aerobic capacity. Adding to that, cardiac rehabs programs are almost base in several activities in a standing position. The cardiac rehabilitation programs have to improve for them, based on scientific advice. Objective: Evaluation of aerobic capacity of diabetic amputee after an aerobic exercise program, with upper limb ergometer. Methodology: The design is longitudinal, prospective, comparative and no randomized. We include all diabetic pelvic limb amputees, who assist to the cardiac rehabilitation. We made 2 groups: an experimental and a control group. The patients did the exercise testing, with the author’s design protocol. The experimental group completed 24 exercise sessions (3 sessions/week), with an intensity determined with the training heart rate. At the end of 8 weeks period, the subjects did a second exercise test. Results: Both groups were a homogeneous sample in age (experimental n=15) 57.6+12.5 years old and (control n=8) 52.5+8.0 years old, sex, occupation, education and economic features. (square chi) (p=0.28). The initial aerobic capacity was similar in both groups. And the aerobic capacity accomplishes after the program was statistically greater in the experimental group than in the control one. The final media VO2peak (mlO2/kg/min) was experimental (17.1+3.8), control (10.5+3.8), p=0.001. (t student). Conclusions: The aerobic capacity improved after an arm ergometer exercise program and the quality of life improve too, in diabetic amputees. So this program is fundamental in diabetic amputee’s rehabilitation management.

Keywords: aerobic fitness, metabolic equivalent (MET), oxygen output, upper limb ergometer

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1271 Association between a Serotonin Re-Uptake Transporter Gene Polymorphism and Mucosal Serotonin Level in Women Patients with Irritable Bowel Syndrome and Healthy Control: A Pilot Study from Northern India

Authors: Sunil Kumar, Uday C. Ghoshal

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Background and aims: Serotonin (5-hydroxtryptamine, 5-HT) is an important factor in gut function, playing key roles in intestinal peristalsis and secretion, and in sensory signaling in the brain-gut axis. Removal from its sites of action is mediated by a specific protein called the serotonin reuptake transporter (SERT). Polymorphisms in the promoter region of the SERT gene have effects on transcriptional activity, resulting in altered 5-HT reuptake efficiency. Functional polymorphisms may underlie disturbance in gut function in individuals suffering with disorders such as irritable bowel syndrome (IBS). The aim of this study was to assess the potential association between SERT polymorphisms and the diarrhea predominant IBS (D-IBS) phenotype Subjects: A total of 36 northern Indian female patients and 55 female northern Indian healthy controls (HC) were subjected to genotyping. Methods: Leucocyte DNA of all subjects was analyzed by polymerase chain reaction based technologies for SERT polymorphisms, specifically the insertion/deletion polymorphism in the promoter (SERT-P). Statistical analysis was performed to assess association of SERT polymorphism allele with the D-IBS phenotype. Results: The frequency of distribution of SERT-P gene was comparable between female patients with IBS and HC (p = 0.086). However, frequency of SERT-P deletion/deletion genotype was significantly higher in female patients with D-IBS compared to C-IBS and A-IBS [17/19 (89.5%) vs. 4/12 (33.3%) vs. 1/5 (20%), p=0.001, respectively]. The mucosal level of serotonin was higher in D-IBS compared to C-IBS and A-IBS [Median, range (159.26, 98.78–212.1) vs. 110.4, 67.87–143.53 vs. 92.34, 78.8–166.3 pmol/mL, p=0.001, respectively]. The mucosal level of serotonin was higher in female patients with IBS with SERT-P deletion/deletion genotype compared deletion/insertion and insertion/insertion [157.65, 67.87–212.1 vs. 110.4, 78.1–143.32 vs. 100.5, 69.1–132.03 pmol/mL, p=0.001, respectively]. Patients with D-IBS with deletion/deletion genotype more often reported symptoms of abdominal pain, discomfort (p=0.025) and bloating (p=0.039). Symptoms development following lactose ingestion was strongly associated with D-IBS and SERT-P deletion/deletion genotype (p=0.004). Conclusions: Significant association was observed between D-IBS and the SERT-P deletion/deletion genotype, suggesting that the serotonin transporter is a potential candidate gene for D-IBS in women.

Keywords: serotonin, SERT, inflammatory bowel disease, genetic polymorphism

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1270 Rare Diagnosis in Emergency Room: Moyamoya Disease

Authors: Ecem Deniz Kırkpantur, Ozge Ecmel Onur, Tuba Cimilli Ozturk, Ebru Unal Akoglu

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Moyamoya disease is a unique chronic progressive cerebrovascular disease characterized by bilateral stenosis or occlusion of the arteries around the circle of Willis with prominent arterial collateral circulation. The occurrence of Moyamoya disease is related to immune, genetic and other factors. There is no curative treatment for Moyamoya disease. Secondary prevention for patients with symptomatic Moyamoya disease is largely centered on surgical revascularization techniques. We present here a 62-year old male presented with headache and vision loss for 2 days. He was previously diagnosed with hypertension and glaucoma. On physical examination, left eye movements were restricted medially, both eyes were hyperemic and their movements were painful. Other neurological and physical examination were normal. His vital signs and laboratory results were within normal limits. Computed tomography (CT) showed dilated vascular structures around both lateral ventricles and atherosclerotic changes inside the walls of internal carotid artery (ICA). Magnetic resonance imaging (MRI) and angiography (MRA) revealed dilated venous vascular structures around lateral ventricles and hyper-intense gliosis in periventricular white matter. Ischemic gliosis around the lateral ventricles were present in the Digital Subtracted Angiography (DSA). After the neurology, ophthalmology and neurosurgery consultation, the patient was diagnosed with Moyamoya disease, pulse steroid therapy was started for vision loss, and super-selective DSA was planned for further investigation. Moyamoya disease is a rare condition, but it can be an important cause of stroke in both children and adults. It generally affects anterior circulation, but posterior cerebral circulation may also be affected, as well. In the differential diagnosis of acute vision loss, occipital stroke related to Moyamoya disease should be considered. Direct and indirect surgical revascularization surgeries may be used to effectively revascularize affected brain areas, and have been shown to reduce risk of stroke.

Keywords: headache, Moyamoya disease, stroke, visual loss

Procedia PDF Downloads 248
1269 Numerical Investigation of a Spiral Bladed Tidal Turbine

Authors: Mohammad Fereidoonnezhad, Seán Leen, Stephen Nash, Patrick McGarry

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From the perspective of research innovation, the tidal energy industry is still in its early stages. While a very small number of turbines have progressed to utility-scale deployment, blade breakage is commonly reported due to the enormous hydrodynamic loading applied to devices. The aim of this study is the development of computer simulation technologies for the design of next-generation fibre-reinforced composite tidal turbines. This will require significant technical advances in the areas of tidal turbine testing and multi-scale computational modelling. The complex turbine blade profiles are designed to incorporate non-linear distributions of airfoil sections to optimize power output and self-starting capability while reducing power fluctuations. A number of candidate blade geometries are investigated, ranging from spiral geometries to parabolic geometries, with blades arranged in both cylindrical and spherical configurations on a vertical axis turbine. A combined blade element theory (BET-start-up model) is developed in MATLAB to perform computationally efficient parametric design optimisation for a range of turbine blade geometries. Finite element models are developed to identify optimal fibre-reinforced composite designs to increase blade strength and fatigue life. Advanced fluid-structure-interaction models are also carried out to compute blade deflections following design optimisation.

Keywords: tidal turbine, composite materials, fluid-structure-interaction, start-up capability

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1268 Classification for Obstructive Sleep Apnea Syndrome Based on Random Forest

Authors: Cheng-Yu Tsai, Wen-Te Liu, Shin-Mei Hsu, Yin-Tzu Lin, Chi Wu

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Background: Obstructive Sleep apnea syndrome (OSAS) is a common respiratory disorder during sleep. In addition, Body parameters were identified high predictive importance for OSAS severity. However, the effects of body parameters on OSAS severity remain unclear. Objective: In this study, the objective is to establish a prediction model for OSAS by using body parameters and investigate the effects of body parameters in OSAS. Methodologies: Severity was quantified as the polysomnography and the mean hourly number of greater than 3% dips in oxygen saturation during examination in a hospital in New Taipei City (Taiwan). Four levels of OSAS severity were classified by the apnea and hypopnea index (AHI) with American Academy of Sleep Medicine (AASM) guideline. Body parameters, including neck circumference, waist size, and body mass index (BMI) were obtained from questionnaire. Next, dividing the collecting subjects into two groups: training and testing groups. The training group was used to establish the random forest (RF) to predicting, and test group was used to evaluated the accuracy of classification. Results: There were 3330 subjects recruited in this study, whom had been done polysomnography for evaluating severity for OSAS. A RF of 1000 trees achieved correctly classified 79.94 % of test cases. When further evaluated on the test cohort, RF showed the waist and BMI as the high import factors in OSAS. Conclusion It is possible to provide patient with prescreening by body parameters which can pre-evaluate the health risks.

Keywords: apnea and hypopnea index, Body parameters, obstructive sleep apnea syndrome, Random Forest

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1267 Incidence of Lymphoma and Gonorrhea Infection: A Retrospective Study

Authors: Diya Kohli, Amalia Ardeljan, Lexi Frankel, Jose Garcia, Lokesh Manjani, Omar Rashid

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Gonorrhea is the second most common sexually transmitted disease (STDs) in the United States of America. Gonorrhea affects the urethra, rectum, or throat and the cervix in females. Lymphoma is a cancer of the immune network called the lymphatic system that includes the lymph nodes/glands, spleen, thymus gland, and bone marrow. Lymphoma can affect many organs in the body. When a lymphocyte develops a genetic mutation, it signals other cells into rapid proliferation that causes many mutated lymphocytes. Multiple studies have explored the incidence of cancer in people infected with STDs such as Gonorrhea. For instance, the studies conducted by Wang Y-C and Co., as well as Caini, S and Co. established a direct co-relationship between Gonorrhea infection and incidence of prostate cancer. We hypothesize that Gonorrhea infection also increases the incidence of Lymphoma in patients. This research study aimed to evaluate the correlation between Gonorrhea infection and the incidence of Lymphoma. The data for the research was provided by a Health Insurance Portability and Accountability Act (HIPAA) compliant national database. This database was utilized to evaluate patients infected with Gonorrhea versus the ones who were not infected to establish a correlation with the prevalence of Lymphoma using ICD-10 and ICD-9 codes. Access to the database was granted by the Holy Cross Health, Fort Lauderdale for academic research. Standard statistical methods were applied throughout. Between January 2010 and December 2019, the query was analyzed and resulted in 254 and 808 patients in both the infected and control group, respectively. The two groups were matched by Age Range and CCI score. The incidence of Lymphoma was 0.998% (254 patients out of 25455) in the Gonorrhea group (patients infected with Gonorrhea that was Lymphoma Positive) compared to 3.174% and 808 patients in the control group (Patients negative for Gonorrhea but with Lymphoma). This was statistically significant by a p-value < 2.210-16 with an OR= 0.431 (95% CI 0.381-0.487). The patients were then matched by antibiotic treatment to avoid treatment bias. The incidence of Lymphoma was 1.215% (82 patients out of 6,748) in the Gonorrhea group compared to 2.949% (199 patients out of 6748) in the control group. This was statistically significant by a p-value <5.410-10 with an OR= 0.468 (95% CI 0.367-0.596). The study shows a statistically significant correlation between Gonorrhea and a reduced incidence of Lymphoma. Further evaluation is recommended to assess the potential of Gonorrhea in reducing Lymphoma.

Keywords: gonorrhea, lymphoma, STDs, cancer, ICD

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1266 Communication Tools Used in Teaching and Their Effects: An Empirical Study on the T. C. Selcuk University Samples

Authors: Sedat Simsek, Tugay Arat

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Today's communication concept, which has a great revolution with the printing press which has been found by Gutenberg, has no boundary thanks to advanced communication devices and the internet. It is possible to take advantage in many areas, such as from medicine to social sciences or from mathematics to education, from the computers that was first produced for the purpose of military services. The use of these developing technologies in the field of education has created a great vision changes in both training and having education. Materials, which can be considered as basic communication resources and used in traditional education has begun to lose its significance, and some technologies have begun to replace them such as internet, computers, smart boards, projection devices and mobile phone. On the other hand, the programs and applications used in these technologies have also been developed. University students use virtual books instead of the traditional printed book, use cell phones instead of note books, use the internet and virtual databases instead of the library to research. They even submit their homework with interactive methods rather than printed materials. The traditional education system, these technologies, which increase productivity, have brought a new dimension to education. The aim of this study is to determine the influence of technologies in the learning process of students and to find whether is there any similarities and differences that arise from the their faculty that they have been educated and and their learning process. In addition to this, it is aimed to determine the level of ICT usage of students studying at the university level. In this context, the advantages and conveniences of the technology used by students are also scrutinized. In this study, we used surveys to collect data. The data were analyzed by using SPSS 16 statistical program with the appropriate testing.

Keywords: education, communication technologies, role of technology, teaching

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1265 Residual Lifetime Estimation for Weibull Distribution by Fusing Expert Judgements and Censored Data

Authors: Xiang Jia, Zhijun Cheng

Abstract:

The residual lifetime of a product is the operation time between the current time and the time point when the failure happens. The residual lifetime estimation is rather important in reliability analysis. To predict the residual lifetime, it is necessary to assume or verify a particular distribution that the lifetime of the product follows. And the two-parameter Weibull distribution is frequently adopted to describe the lifetime in reliability engineering. Due to the time constraint and cost reduction, a life testing experiment is usually terminated before all the units have failed. Then the censored data is usually collected. In addition, other information could also be obtained for reliability analysis. The expert judgements are considered as it is common that the experts could present some useful information concerning the reliability. Therefore, the residual lifetime is estimated for Weibull distribution by fusing the censored data and expert judgements in this paper. First, the closed-forms concerning the point estimate and confidence interval for the residual lifetime under the Weibull distribution are both presented. Next, the expert judgements are regarded as the prior information and how to determine the prior distribution of Weibull parameters is developed. For completeness, the cases that there is only one, and there are more than two expert judgements are both focused on. Further, the posterior distribution of Weibull parameters is derived. Considering that it is difficult to derive the posterior distribution of residual lifetime, a sample-based method is proposed to generate the posterior samples of Weibull parameters based on the Monte Carlo Markov Chain (MCMC) method. And these samples are used to obtain the Bayes estimation and credible interval for the residual lifetime. Finally, an illustrative example is discussed to show the application. It demonstrates that the proposed method is rather simple, satisfactory, and robust.

Keywords: expert judgements, information fusion, residual lifetime, Weibull distribution

Procedia PDF Downloads 122
1264 Soil Salinity from Wastewater Irrigation in Urban Greenery

Authors: H. Nouri, S. Chavoshi Borujeni, S. Anderson, S. Beecham, P. Sutton

Abstract:

The potential risk of salt leaching through wastewater irrigation is of concern for most local governments and city councils. Despite the necessity of salinity monitoring and management in urban greenery, most attention has been on agricultural fields. This study was defined to investigate the capability and feasibility of monitoring and predicting soil salinity using near sensing and remote sensing approaches using EM38 surveys, and high-resolution multispectral image of WorldView3. Veale Gardens within the Adelaide Parklands was selected as the experimental site. The results of the near sensing investigation were validated by testing soil salinity samples in the laboratory. Over 30 band combinations forming salinity indices were tested using image processing techniques. The outcomes of the remote sensing and near sensing approaches were compared to examine whether remotely sensed salinity indicators could map and predict the spatial variation of soil salinity through a potential statistical model. Statistical analysis was undertaken using the Stata 13 statistical package on over 52,000 points. Several regression models were fitted to the data, and the mixed effect modelling was selected the most appropriate one as it takes to account the systematic observation-specific unobserved heterogeneity. Results showed that SAVI (Soil Adjusted Vegetation Index) was the only salinity index that could be considered as a predictor for soil salinity but further investigation is needed. However, near sensing was found as a rapid, practical and realistically accurate approach for salinity mapping of heterogeneous urban vegetation.

Keywords: WorldView3, remote sensing, EM38, near sensing, urban green spaces, green smart cities

Procedia PDF Downloads 138
1263 A Practice Model for Quality Improvement in Concrete Block Mini Plants Based on Merapi Volcanic Sand

Authors: Setya Winarno

Abstract:

Due to abundant Merapi volcanic sand in Yogyakarta City, many local people have utilized it for mass production of concrete blocks through mini plants although their products are low in quality. This paper presents a practice model for quality improvement in this situation in order to supply the current customer interest in good quality of construction material. The method of this research was to investigate a techno economic evaluation through laboratory test and interview. Samples of twenty existing concrete blocks made by local people had only 19.4 kg/cm2 in average compression strength which was lower than the minimum Indonesian standard of 25 kg/cm2. Through repeat testing in laboratory for fulfilling the standard, the concrete mix design of water cement ratio should not be more than 0.64 by weight basis. The proportion of sand as aggregate content should not be more than 9 parts to 1 part by volume of Portland cement. Considering the production cost, the basic price was Rp 1,820 for each concrete block, comparing to Rp 2,000 as a normal competitive market price. At last, the model describes (a) maximum water cement ratio is 0.64, (b) maximum proportion of sand and cement is 1:9, (c) the basic price is about Rp. 1,820.00 and (d) strategies to win the competitive market on mass production of concrete blocks are focus in quality, building relationships with consumer, rapid respond to customer need, continuous innovation by product diversification, promotion in social media, and strict financial management.

Keywords: concrete block, good quality, improvement model, diversification

Procedia PDF Downloads 498
1262 Effect of Fiber Orientation on the Mechanical Properties of Fabricated Plate Using Basalt Fiber

Authors: Sharmili Routray, Kishor Chandra Biswal

Abstract:

The use of corrosion resistant fiber reinforced polymer (FRP) reinforcement is beneficial in structures particularly those exposed to deicing salts, and/or located in highly corrosive environment. Generally Glass, Carbon and Aramid fibers are used for the strengthening purpose of the structures. Due to the necessities of low weight and high strength materials, it is required to find out the suitable substitute with low cost. Recent developments in fiber production technology allow the strengthening of structures using Basalt fiber which is made from basalt rock. Basalt fiber has good range of thermal performance, high tensile strength, resistance to acids, good electro‐magnetic properties, inert nature, resistance to corrosion, radiation and UV light, vibration and impact loading. This investigation focuses on the effect of fibre content and fiber orientation of basalt fibre on mechanical properties of the fabricated composites. Specimen prepared with unidirectional Basalt fabric as reinforcing materials and epoxy resin as a matrix in polymer composite. In this investigation different fiber orientation are taken and the fabrication is done by hand lay-up process. The variation of the properties with the increasing number of plies of fiber in the composites is also studied. Specimens are subjected to tensile strength test and the failure of the composite is examined with the help of INSTRON universal testing Machine (SATEC) of 600 kN capacities. The average tensile strength and modulus of elasticity of BFRP plates are determined from the test Program.

Keywords: BFRP, fabrication, Fiber Reinforced Polymer (FRP), strengthening

Procedia PDF Downloads 270
1261 Empowering Women through the Fishermen of Functional Skills for City Gorontalo Indonesia

Authors: Abdul Rahmat

Abstract:

Community-based education in the economic empowerment of the family is an attempt to accelerate human development index (HDI) Dumbo Kingdom District of Gorontalo economics (purchasing power) program developed in this activity is the manufacture of functional skills shredded fish, fish balls, fish nuggets, chips anchovies, and corn sticks fish. The target audience of this activity is fishing se mothers subdistrict Dumbo Kingdom include Talumolo Village, Village Botu, Kampung Bugis Village, Village North and Sub Leato South Leato that each village is represented by 20 participants so totaling 100 participants. Time activities beginning in October s/d November 2014 held once a week on every Saturday at 9.00 s/d 13:00/14:00. From the results of the learning process of testing the skills of functional skills of making shredded fish, fish balls, fish nuggets, chips anchovies, fish and corn sticks residents have additional knowledge and experience are: 1) Order the concept include: nutrient content, processing food with fish raw materials , variations in taste, packaging, pricing and marketing sales. 2) Products made: in accordance with the wishes of the residents learned that estimated Eligible selling, product packaging logo creation, preparation and realization of the establishment of Business Study Group (KBU) and pioneered the marketing network with restaurant, store / shop staple food vendors that are around CLC.

Keywords: community development, functional skills, gender, HDI

Procedia PDF Downloads 298
1260 Contribution to the Production of Phenazine Antibiotics Effect Type Compounds by Some Strains of Pseudomonas spp.fluorescent

Authors: Nacéra Benoussaid, Lehalali Meriem, Benchabane Messaoud

Abstract:

Our work focuses on the production of compound antibiotic effect of volatile nature namely hydrogen cyanide and the production and identification of molecules phénazinique by some strains of fluorescent Pseudomonas spp isolated from the rhizosphere of some trees for a possible use as bio pesticides antifungal effect and/or antibiotic. We tested the production of hydrogen cyanide of 21 strains of Pseudomonas spp. fluorescent among them 19 strains (90, 47%) showed a positive cyanogenesis.The antagonism test executed in vitro showed that Pseudomonas strains have a higher anti fungal effect relative to their antibacterial effect with diameters of inhibition zones up to 3, 9 cm recorded by the strain F48 against Coleosporiumsp compared with recorded results against bacteria with a maximum inhibition of 1, 26 cm among this antagonistic strain.Three strains were selected by testing for producing phénazines namely PI9, BB9 and F20. The effect of the antimicrobial activity was performed on different culture media (GN, King B, ISP2 and PDA). The results of our study allowed us to retain the King B medium as ideal medium for the production of secondary metabolite. The produced phenazinique compounds was extracted from various organic solvents, and after the results of antibiographie against germs - targets, the extracts of ethyl acetate gave the best results compared to dichloromethane and hexane.The Analysis of these compounds of antibiotic phenazinique effect within layer chromatography (CCM) and high performance liquid chromatography( HPLC) indicate that both strains PI9 and F20 are productive of phenazine-1-carboxylic acid (PCA). The BB9 strain is suspected to be productive of another phenazinique compound.

Keywords: Pseudomonas ssp. fluorescents, antagonism in vitro, secondary metabolite, phenazines, biopesticide.

Procedia PDF Downloads 493
1259 Geosynthetic Reinforced Unpaved Road: Literature Study and Design Example

Authors: D. Jayalakshmi, S. S. Bhosale

Abstract:

This paper, in its first part, presents the state-of-the-art literature of design approaches for geosynthetic reinforced unpaved roads. The literature starting since 1970 and the critical appraisal of flexible pavement design by Giroud and Han (2004) and Jonathan Fannin (2006) is presented. The design example is illustrated for Indian conditions. The example emphasizes the results computed by Giroud and Han's (2004) design method with the Indian road congress guidelines by IRC SP 72 -2015. The input data considered are related to the subgrade soil condition of Maharashtra State in India. The unified soil classification of the subgrade soil is inorganic clay with high plasticity (CH), which is expansive with a California bearing ratio (CBR) of 2% to 3%. The example exhibits the unreinforced case and geotextile as reinforcement by varying the rut depth from 25 mm to 100 mm. The present result reveals the base thickness for the unreinforced case from the IRC design catalogs is in good agreement with Giroud and Han (2004) approach for a range of 75 mm to 100 mm rut depth. Since Giroud and Han (2004) method is applicable for both reinforced and unreinforced cases, for the same data with appropriate Nc factor, for the same rut depth, the base thickness for the reinforced case has arrived for the Indian condition. From this trial, for the CBR of 2%, the base thickness reduction due to geotextile inclusion is 35%. For the CBR range of 2% to 5% with different stiffness in geosynthetics, the reduction in base course thickness will be evaluated, and the validation will be executed by the full-scale accelerated pavement testing set up at the College of Engineering Pune (COE), India.

Keywords: base thickness, design approach, equation, full scale accelerated pavement set up, Indian condition

Procedia PDF Downloads 169
1258 Local Interpretable Model-agnostic Explanations (LIME) Approach to Email Spam Detection

Authors: Rohini Hariharan, Yazhini R., Blessy Maria Mathew

Abstract:

The task of detecting email spam is a very important one in the era of digital technology that needs effective ways of curbing unwanted messages. This paper presents an approach aimed at making email spam categorization algorithms transparent, reliable and more trustworthy by incorporating Local Interpretable Model-agnostic Explanations (LIME). Our technique assists in providing interpretable explanations for specific classifications of emails to help users understand the decision-making process by the model. In this study, we developed a complete pipeline that incorporates LIME into the spam classification framework and allows creating simplified, interpretable models tailored to individual emails. LIME identifies influential terms, pointing out key elements that drive classification results, thus reducing opacity inherent in conventional machine learning models. Additionally, we suggest a visualization scheme for displaying keywords that will improve understanding of categorization decisions by users. We test our method on a diverse email dataset and compare its performance with various baseline models, such as Gaussian Naive Bayes, Multinomial Naive Bayes, Bernoulli Naive Bayes, Support Vector Classifier, K-Nearest Neighbors, Decision Tree, and Logistic Regression. Our testing results show that our model surpasses all other models, achieving an accuracy of 96.59% and a precision of 99.12%.

Keywords: text classification, LIME (local interpretable model-agnostic explanations), stemming, tokenization, logistic regression.

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1257 Chronic Cognitive Impacts of Mild Traumatic Brain Injury during Aging

Authors: Camille Charlebois-Plante, Marie-Ève Bourassa, Gaelle Dumel, Meriem Sabir, Louis De Beaumont

Abstract:

To the extent of our knowledge, there has been little interest in the chronic effects of mild traumatic brain injury (mTBI) on cognition during normal aging. This is rather surprising considering the impacts on daily and social functioning. In addition, sustaining a mTBI during late adulthood may increase the effect of normal biological aging in individuals who consider themselves normal and healthy. The objective of this study was to characterize the persistent neuropsychological repercussions of mTBI sustained during late adulthood, on average 12 months prior to testing. To this end, 35 mTBI patients and 42 controls between the ages of 50 and 69 completed an exhaustive neuropsychological assessment lasting three hours. All mTBI patients were asymptomatic and all participants had a score ≥ 27 at the MoCA. The evaluation consisted of 20 standardized neuropsychological tests measuring memory, attention, executive and language functions, as well as information processing speed. Performance on tests of visual (Brief Visuospatial Memory Test Revised) and verbal memory (Rey Auditory Verbal Learning Test and WMS-IV Logical Memory subtest), lexical access (Boston Naming Test) and response inhibition (Stroop) revealed to be significantly lower in the mTBI group. These findings suggest that a mTBI sustained during late adulthood induces lasting effects on cognitive function. Episodic memory and executive functions seem to be particularly vulnerable to enduring mTBI effects.

Keywords: cognitive function, late adulthood, mild traumatic brain injury, neuropsychology

Procedia PDF Downloads 150
1256 Effect of External Radiative Heat Flux on Combustion Characteristics of Rigid Polyurethane Foam under Piloted-Ignition and Radiative Auto-Ignition Modes

Authors: Jia-Jia He, Lin Jiang, Jin-Hua Sun

Abstract:

Rigid polyurethane foam (RPU) has been extensively applied in building insulation system, yet with high flammability for being easily ignited by high temperature spark or radiative heat flux from other flaming materials or surrounding building facade. Using a cone calorimeter by Fire Testing Technology and thermal couple tree, this study systematically investigated the effect of radiative heat flux on the ignition time and characteristic temperature distribution during RPU combustion under different heat fluxes gradient (12, 15, 20, 25, 30, 35, 40, 45, and 50 kW/m²) with spark ignition/ignition by radiation. The ignition time decreases proportionally with increase of external heat flux, meanwhile increasing the external heat flux raises the peak heat release rate and impresses on the vertical temperature distribution greatly. The critical ignition heat flux is found to be 15 and 25 kW/m² for spark ignition and radiative ignition, respectively. Based on previous experienced ignition formula, a methodology to predict ignition times in both modes has been developed theoretically. By analyzing the heat transfer mechanism around the sample surroundings, both radiation from cone calorimeter and convection flow are considered and calculated theoretically. The experimental ignition times agree well with the theoretical ones in both radiative and convective conditions; however, the observed critical ignition heat flux is higher than the calculated one under piloted-ignition mode because the heat loss process, especially in lower heat flux radiation, is not considered in this developed methodology.

Keywords: rigid polyurethane foam, cone calorimeter, ignition time, external heat flux

Procedia PDF Downloads 180
1255 Testing the Possibility of Healthy Individuals to Mimic Fatigability in Multiple Sclerotic Patients

Authors: Emmanuel Abban Sagoe

Abstract:

A proper functioning of the Central Nervous System ensures that we are able to accomplish just about everything we do as human beings such as walking, breathing, running, etc. Myelinated neurons throughout the body which transmit signals at high speeds facilitate these actions. In the case of MS, the body’s immune system attacks the myelin sheath surrounding the neurons and overtime destroys the myelin sheaths. Depending upon where the destruction occurs in the brain symptoms can vary from person to person. Fatigue is, however, the biggest problem encountered by an MS sufferer. It is very often described as the bedrock upon which other symptoms of MS such challenges in balance and coordination, dizziness, slurred speech, etc. may occur. Classifying and distinguishing between perceptions based fatigue and performance based fatigability is key to identifying appropriate treatment options for patients. Objective methods for assessing motor fatigability is also key to providing clinicians and physiotherapist with critical information on the progression of the symptom. This study tested if the Fatigue Index Kliniken Schmieder assessment tool can detect fatigability as seen in MS patients when healthy subjects with no known history of neurological pathology mimic abnormal gaits. Thirty three healthy adults between ages 18-58years volunteered as subjects for the study. The subjects, strapped with RehaWatch sensors on both feet, completed 6 gait protocols of normal and mimicked fatigable gaits for 60 seconds per each gait and at 1.38889m/s treadmill speed following clear instructions given.

Keywords: attractor attributes, fatigue index Kliniken Schmieder, gait variability, movement pattern

Procedia PDF Downloads 103
1254 Prevalence of Cytomegalovirus DNA in the Patients’ Serum with HIV using Real-Time PCR

Authors: Mohammadreza Aghasadeghi, Mojtaba Hamidi-Fard, Seyed Amir Sadeghi, Ashkan Noorbakhsh

Abstract:

Introduction: HIV is known as one of the most important pathogens and mortality in all human societies, but unfortunately, no definitive cure has been found for it. Due to its weakened immune system, this virus causes a variety of primary and secondary opportunistic infections. Cytomegalovirus (CMV) is one of the most relevant opportunistic viruses seen in HIV-positive people that cause various infections in HIV-positive people. This virus causes various infections in HIV-positive people, such as retinal infection (CMVR), gastrointestinal infections, diarrhea, severe weight loss, and cerebrospinal fluid problems. These various infections make it important to evaluate the prevalence of CMV in HIV-positive people to diagnose it quickly and in a timely manner. This infection in HIV-positive people reduces life expectancy and causes serious harm to patients. However, a simple test in HIV-positive people can prevent the virus from progressing. Material and Methods: In this study, we collected 200 blood samples (including 147 men and 53 women) from HIV-positive individuals and examined the frequency of CMV-DNA in these cases by real-time PCR method. In the next step, the data was analyzed by SPSS software, and then we obtained the relationship between age, sex, and the frequency of CMV in HIV-positive individuals. Results: The total frequency of CMV DNA was about 59%, which is a relatively high prevalence due to the age range of the subjects. The frequency in men was 61.2% and 52.8% in women. This frequency was also higher in males than females. We also observed more frequency in two age groups of 16 to 30 years and 31 to 45 years. Discussion: Due to the high prevalence of CMV in HIV-positive individuals and causing serious problems in this group of people, this study was shown that both the patients and the community should pay more attention to this issue. Ministry of Health, as a stakeholder organization, can make CMV DNA testing mandatory as soon as a person is HIV positive.

Keywords: CMV, HIV, AIDS, real-time PCR, SPSS

Procedia PDF Downloads 193
1253 Design and Radio Frequency Characterization of Radial Reentrant Narrow Gap Cavity for the Inductive Output Tube

Authors: Meenu Kaushik, Ayon K. Bandhoyadhayay, Lalit M. Joshi

Abstract:

Inductive output tubes (IOTs) are widely used as microwave power amplifiers for broadcast and scientific applications. It is capable of amplifying radio frequency (RF) power with very good efficiency. Its compactness, reliability, high efficiency, high linearity and low operating cost make this device suitable for various applications. The device consists of an integrated structure of electron gun and RF cavity, collector and focusing structure. The working principle of IOT is a combination of triode and klystron. The cathode lies in the electron gun produces a stream of electrons. A control grid is placed in close proximity to the cathode. Basically, the input part of IOT is the integrated structure of gridded electron gun which acts as an input cavity thereby providing the interaction gap where the input RF signal is applied to make it interact with the produced electron beam for supporting the amplification phenomena. The paper presents the design, fabrication and testing of a radial re-entrant cavity for implementing in the input structure of IOT at 350 MHz operating frequency. The model’s suitability has been discussed and a generalized mathematical relation has been introduced for getting the proper transverse magnetic (TM) resonating mode in the radial narrow gap RF cavities. The structural modeling has been carried out in CST and SUPERFISH codes. The cavity is fabricated with the Aluminum material and the RF characterization is done using vector network analyzer (VNA) and the results are presented for the resonant frequency peaks obtained in VNA.

Keywords: inductive output tubes, IOT, radial cavity, coaxial cavity, particle accelerators

Procedia PDF Downloads 97