Search results for: diarrhea predominant Irritable Bowel Syndrome

Authors: Melba D. Horton

Abstract:

Algae are identified as an alternative source of biofuel because of their ubiquitous distribution in aquatic environments. Diatoms are unique forms of algae characterized by silicified cell walls which have gained prominence in various technological applications. Polk County is home to a multitude of ponds and lakes but has not been explored for the presence of diatoms. Considering the condition of the waters brought about by predominant phosphate mining activities in the area, this research was conducted to determine if endemic diatoms are present and explore their potential for low-cost mass production. Using custom-built photobioreactors, water samples from various lakes provided by the Polk County Parks and Recreation and from nearby ponds were used as the source of diatoms together with other algae obtained during collection. Results of the initial culture cycles were successful, but later an overgrowth of other algae crashed the diatom population. Experiments were conducted in the laboratory to tease out some factors possibly contributing to the die-off. Generally, the total biomass declines after two culture cycles and the causative factors need further investigation. The lipid yield is minimum; however, the high frustule production after die-off adds value to the overall benefit of the harvest.

Keywords: diatoms, algae, biofuel, lipid, photobioreactor, frustule

Procedia PDF Downloads 167

Authors: Agnieszka Fryźlewicz, Jowita Kras, Mikołaj Sadowski, Agnieszka Łapczuk-Krygier, Agnieszka Kącka-Zych Radomir Jasiński

Abstract:

Nicotines are a group of compounds containing conjugated pyridine and pyrrolidine molecular segments. They are widely applied in medicine, pharmacy, and agriculture. Namely as researched treatment of Alzheimer, depression, Parkinson's, Tourette syndrome, general nervous and mental disorders. Furthermore, nicotine itself is used as a stimulant, animal repellent and was widely applied as an insecticide. In our work, we obtained nicotine analogues with possible applications in agriculture. The synthesis employed [3+2] cycloaddition (32CA) reactions, occurring between pirydyl-functionalised nitrones and conjugated nitroalkenes, that allowed us to fully regio- and stereoselectively obtain product. Moreover, cycloaddition reaction realizes rapidly in mild conditions with the full atomic economy, thus fitting into “green chemistry” trends.

Keywords: nicotine, isoxazolidine, 1-3-dipolar cycloaddition, green chemistry, biological and pharmacological activity

Procedia PDF Downloads 63

Authors: Barsharani Maharana

Abstract:

India is the country that shelters the largest number of poor. One of the major areas of concern in India is the unsatisfactory situation of the poor in social developmental and health parameters, not only in rural areas which are partly devoid of the facilities but also in the urban areas where the facilities are insufficient to provide services of a satisfactory quality. Objectives: 1) to examine the association between the environmental condition and health condition among poor women in urban areas. 2) to find out the significance of the effect of environment on the child health among the poor children. 3) to present the scenario of poor among highly urbanized and less urbanized states with respect to the health and environment. Data: data from National Family Health survey-3 and census are used to fulfill the objectives. Methodology: In this study, the standard of living condition of people living in urban areas is computed by taking some household characteristics and assets. People possessing low standard of living are considered as poor. Bivariate and multivariate analysis are employed to examine the effect of environment on poor women and children. A geographical information system is used to present the health and environmental condition of poor in highly and less urbanized states. Results: The findings reveal that the poor women who are not accessed to improved source of water, and sanitation facility are facing more health problems. Children who are living in a dirty environment and are not accessed to improved source of drinking water, among them prevalence of diarrhea and fever is found to be high. As well, the health condition of poor in highly urbanized states is dreadful. Policy implications: Government should emphasize on the implementation of programs regarding the improvement in the infrastructural facilities and health care treatment of urban poor.

Keywords: environment, urban poor, health, sanitation

Procedia PDF Downloads 260

Authors: Syeda Fatima Manzelat

Abstract:

The present study aims to study the groups of algal genera which are responsible for the biodeterioration, biodegradation and biological pollution of the structures and features of the two historic parks of UK. Different sites of Campbell Park and Great Linford Manor Park in Milton Keynes are selected to study morphological, aesthetic and physical effect of the algal growth. Specimens and swabs were collected mechanically from selected sites. Algal specimens are preserved in Lugol’s solution and labelled with standard information. Photomicrograph analysis of slides using taxonomic keys and visual observation identified algal species that are homogenously and non-homogenously mixed in the aerial, terrestrial and aquatic habitats. Qualitative study revealed seven classes of Algae. Most of the algal genera isolated are with proven records of potential biodegradation, discoloration and biological pollution. Chlorophyceae was predominant represented by eleven genera Chlorella, Chlorococcum Cladophora, Coenochloris Cylindrocapsa. Microspora, Prasiola, Spirogyra, Trentepholia, Ulothrix and Zygnema. Charophyceae is represented by four genera Cosmarium Klebsormidium, Mesotaenium and Mougeotia. Xanthophyceae with two genera Tribonema andVaucheria. Bacillariophyceae (Diatoms) represented by six genera Acnanthes, Bacillaria, Fragilaria, Gomphonema, Synedra and Tabellaria. Dinophyceae with a Dinoflagellate. Rhodophyceae included Bangia and Batrachospermum. Cyanophyceae with five genera, Chroococcus, Gloeocapsa, Scytonema, Stigonema and Oscillatoria. The quantitative analysis by statistical method revealed that Chlorophyceae was the predominant class with eleven genera isolated from different sites of the two parks. Coenochloris of Chlorophyceae was isolated from thirteen sites during the study followed by Gloeocapsa of Cyanophyceae which is isolated from 12 sites. These two algae impart varying shades of green colour on the surfaces on which they form biofilms. Prasiola, Vaucheria and Trentepholia were isolated only from Great Linford Park. Trentepholia imparted a significant orange colour to the walls and trees of the sites. The compounds present in algae that are responsible for discoloration are the green pigment chlorophyll, orange pigment β-carotene and yellow pigment quinone. Mesotaenium, Dinoflagellate, Gomphonema, Fragilaria, Tabellaria and 2 unidentified genera were isolated from Campbell Park only. Largest number of algal genera (25) were isolated from the canal of Campbell Park followed by (21) from the canal at Great Linford Manor Park. The Algae were found to grow on surfaces of walls, wooden fencings, metal sculptures and railing. The Algae are reported to induce surface erosion, natural weathering and cracking leading to technical and mechanical instability and extensive damage to building materials The algal biofilms secrete different organic acids which are responsible for bio solubilization and biodeterioration of the building materials. The aquatic algal blooms isolated during the study release toxins which are responsible for allergy, skin rashes, vomiting, diarrhoea, fever, muscle spasms, lung and throat infections The study identifies the places and locations at the historic sites which need to be paid attention. It provides an insight to the conservation strategies to overcome the negative impacts of bio colonization by algae. Prevention measures by different treatments need to be regularly monitored.

Keywords: algae, biodeterioration, historic gardens, UK

Procedia PDF Downloads 23

Authors: Muhammad Saqlain, Nazar Abbas Saqib, Muazzam A. Khan

Abstract:

Heart Failure (HF) has become the major health problem in our society. The prevalence of HF has increased as the patient’s ages and it is the major cause of the high mortality rate in adults. A successful identification and progression of HF can be helpful to reduce the individual and social burden from this syndrome. In this study, we use a real data set of cardiac patients to propose a classification model for the identification and progression of HF. The data set has divided into three age groups, namely young, adult, and old and then each age group have further classified into four classes according to patient’s current physical condition. Contemporary Data Mining classification algorithms have been applied to each individual class of every age group to identify the HF. Decision Tree (DT) gives the highest accuracy of 90% and outperform all other algorithms. Our model accurately diagnoses different stages of HF for each age group and it can be very useful for the early prediction of HF.

Keywords: decision tree, heart failure, data mining, classification model

Procedia PDF Downloads 388

Authors: Khabat Barkhordari, Ali Mohammad Arabzadeh

Abstract:

Hepatitis delta virus (HDV) is a RNA virus that needs the function of hepatitis B virus (HBV) for its propagation and assembly. Infection by HDV can occur spontaneously with HBV infection and cause acute hepatitis or develop as secondary infection in HBV suffering patients. Based on genome sequence analysis, HDV has several genotypes which show broad geographic and diverse clinical features. The aim of current study is determine the prevalence of hepatitis delta virus genotype in patients with positive HBsAg in Kerman province of Iran. This cross-sectional study a total of 400 patients with HBV infection attending the clinic center of Besat from 2012 to 2014 were included. We carried out ELISA to detect anti-HDV antibodies. Those testing positive were analyzed further for HDV-RNA and for genotyping using restriction fragment length polymorphism (RFLP) and RT-nested PCR- sequencing. Among 400 patients in this study, 67 cases (16.75 %) were containing anti-HDV antibody which we found HDV RNA in just 7 (1.75%) serum samples. Analysis of these 7 positive HDV showed that all of them have genotype I. According to current study the HDV prevalence in Kerman is higher than the reported prevalence of 6.6% for Iran as a whole and clade 1 (genotype 1) is the predominant clade of HDV in Kerman.

Keywords: genotyping, hepatitis delta virus, molecular epidemiology, Kerman, Iran

Procedia PDF Downloads 272

Authors: Issa M. Hweidi, Saba W. Al-Ibraheem

Abstract:

This study aimed to assess the increased hospital length of stay and healthcare costs associated with SSIs among ventriculoperitoneal shunting surgery patients in Jordan. This study adopted a retrospective and nested 1:1 matched case-control design. A non-probability convenient sample of 48 VP shunt patients was recruited for the purpose of the study. The targeted groups of the study basically used to cross-match the variables investigated to minimize the risk of confounding. Information was extracted from the text of patients' electronic health records. As compared to the non-SSI group, the SSI group had an extra mean healthcare cost of $13,696.53 (p=0.001) and longer hospital length of stay (22.64 mean additional days). Furthermore, Acinetobacter baumannii and Klebsiella pneumonia were identified as being the most predominant causative agents of SSIs. The results of this study may provide baseline data for national and regional benchmarking to evaluate the quality of care provided to likewise patients. Adherence to infection control strategies and protocols considering new surveillance methods of SSIs is encouraged.

Keywords: ventriculoperitoneal shunt, health care cost, length of stay, neurosurgery, surgical site infections

Procedia PDF Downloads 54

Authors: Franck kem Acho

Abstract:

This is a chronic metabolic disorder which is a fast-growing global problem with a huge social, health, and economic consequences. It is estimated that in 2010 there were globally 285 million people (approximately 6.4% of the adult population) suffering from this disease. This number is estimated to increase to 430 million in the absence of better control or cure. An ageing population and obesity are two main reasons for the increase. Diabetes mellitus is a chronic heterogeneous metabolic disorder with a complex pathogenesis. It is characterized by elevated blood glucose levels or hyperglycemia, which results from abnormalities in either insulin secretion or insulin action or both. Hyperglycemia manifests in various forms with a varied presentation and results in carbohydrate, fat, and protein metabolic dysfunctions. Long-term hyperglycemia often leads to various microvascular and macrovascular diabetic complications, which are mainly responsible for diabetes-associated morbidity and mortality. Hyperglycemia serves as the primary biomarker for the diagnosis of diabetes as well. Furthermore, it has been shown that almost 50% of the putative diabetics are not diagnosed until 10 years after onset of the disease, hence the real prevalence of global diabetes must be astronomically high. This study was conducted in a locality to access the level of knowledge, awareness and risk factors associated with people leaving with diabetes mellitus. A month before the screening was to be conducted, a health screening in some selected churches and on the local community radio as well as on relevant WhatsApp groups were advertised. A general health talk was delivered by the head of the screening unit to all attendees who were all educated on the procedure to be carried out with benefits and any possible discomforts after which the attendee’s consent was obtained. Evaluation of the participants for any leads to the diabetes selected for the screening was done by taking adequate history and physical examinations such as excessive thirst, increased urination, tiredness, hunger, unexplained weight loss, feeling irritable or having other mood changes, having blurry vision, having slow-healing sores, getting a lot of infections, such as gum, skin and vaginal infections. Out of the 94 participants the finding show that 78 were females and 16 were males, 70.21% of participants with diabetes were between the ages of 60-69yrs.The study found that only 10.63% of respondents declared a good level of knowledge of diabetes. Out of 3 symptoms of diabetes analyzed in this study, high blood sugar (58.5%) and chronic fatigue (36.17%) were the most recognized. Out of 4 diabetes risk factors analyzed in this study, obesity (21.27%) and unhealthy diet (60.63%) were the most recognized diabetes risk factors, while only 10.6% of respondents indicated tobacco use. The diabetic foot was the most recognized diabetes complication (50.57%), but some the participants indicated vision problems (30.8%),or cardiovascular diseases (20.21%) as diabetes complications.

Keywords: diabetes mellitus, non comunicable disease, general health talk, hyperglycemia

Procedia PDF Downloads 41

Authors: Syed Asif Ali Naqvi, Muhammad Azeem Tufail

Abstract:

Inadequate sanitation causes direct costs of treating illnesses and loss of income through reduced productivity. This study estimated the economic cost of health (ECH) due to poor sanitation and factors determining the lack of access to latrine for the rural, backward hamlets and slums of district Faisalabad, Pakistan. Cross sectional data were collected and analyzed for the study. As the population under study was homogenous in nature, it is why a simple random sampling technique was used for the collection of data. Data of 440 households from 4 tehsils were gathered. The ordinary least square (OLS) model was used for health cost analysis, and the Probit regression model was employed for determining the factors responsible for inaccess to toilets. The results of the study showed that condition of toilets, situation of sewerage system, access to adequate sanitation, Cholera, diarrhea and dysentery, Water and Sanitation Agency (WASA) maintenance, source of medical treatment can plausibly have a significant connection with the dependent variable. Outcomes of the second model showed that the variables of education, family system, age, and type of dwelling have positive and significant sway with the dependent variable. Variable of age depicted an insignificant association with access to toilets. Variable of monetary expenses would negatively influence the dependent variable. Findings revealed the fact, health risks are often exacerbated by inadequate sanitation, and ultimately, the cost on health also surges. Public and community toilets for youths and social campaigning are suggested for public policy.

Keywords: sanitation, toilet, economic cost of health, water, Punjab

Procedia PDF Downloads 105

Authors: Elly Usman, S. Dante, Diah Purnamasari

Abstract:

Type 2 diabetes mellitus ( T2DM ) is a syndrome characterized by a state of increased blood sugar levels due to chronic disorders of insulin secretion by pancreatic beta cells and insulin action or a combination of both. The organic cation transporter 1, encoded by the SLC22A1 gene, responsible for the uptake of the antihyperglycemic drug, metformin, in the hepatocyte. We assessed whether a genetic variation in the SLC22A1 gene was associated with the glucose - lowering effect of metformin. Method case study research design. Samples are children with type 2 diabetes mellitus who meet the inclusion criteria. The results proportions SLC22A1 gene polymorphisms in children with diabetes mellitus type 2 amounted to 52.04 % at position 400T/C, there is one heterozygous and one at position 595T/C Conclusion The presence of SLC22A1 gene polymorphisms in children with diabetes mellitus type 2.

Keywords: diabetes Mellitus type 2, metformin, organic cation transporter 1, pharmacogenomics

Procedia PDF Downloads 409

Authors: A. Hoppe, T. Kagele, B. Hall, A. Nichols, B. Messner

Abstract:

The Spokane Street Medicine (SSM) Program aims to deliver medical care to members of Spokane, Washington, experiencing homelessness. Street medicine is designed to function in a non-traditional setting to help deliver healthcare to the underserved homeless population. In this analysis, clinical charts from street and shelter encounters made by the Spokane Street Medicine Program in early 2021 were reviewed in order to better understand the healthcare inequities prevalent among people experiencing homelessness in Spokane, WA. Pain, wound-care, and follow-up efforts were predominant concerns among the homeless population. More than half of the conditions addressed were acute, and almost a quarter of all chief complaints involved chronic unmanaged conditions. This analysis gives reason for the priorities of the SSM Program to be focused on pain, wound-care, and follow-up efforts. Understanding the specific medical needs of this population will allow for better resource allocation and improved health outcomes among people experiencing homelessness.

Keywords: equity issues in public health, health disparities, health services accessibility, medical public health, street medicine

Procedia PDF Downloads 171

Authors: Neda Valizadeh, Soudabeh Shafiee Ardestani, Arvin Najafi

Abstract:

Objectives: The aim of this study is to evaluate the association of mid-regional pro-atrial natriuretic peptide (MRproANP), procalcitonin (PCT), proendothelin-1 (proET-1) levels with sepsis severity in Emergency ward patients. Materials and Methods: We assessed the predictive value of MRproANP, PCT, copeptin, and proET-1 in early sepsis among patients referring to the emergency ward with a suspected sepsis. Results-132 patients were enrolled in this study. 45 (34%) patients had a final diagnosis of sepsis. A higher percentage of patients with definite sepsis had systemic inflammatory response syndrome (SIRS) criteria at initial visit in comparison with no-sepsis patients (P<0.05) and were admitted to the hospital (P<0.05). PCT levels were higher in sepsis patients [P<0.05]. There was no significant differences for MRproANP or proET-1 in sepsis patients (P=0.47). Conclusion: A combination of SIRS criteria and PCT levels is beneficial for the early sepsis diagnosis in emergency ward patients with a suspicious infection disease.

Keywords: emergency, prolactin, sepsis, biomarkers

Procedia PDF Downloads 420

Authors: Kennedy Zinn, Chris Anderson

Abstract:

Chronic Covid syndrome (CCS) is a condition in which individuals who test positive for Covid-19 experience persistent symptoms after recovering from the virus. CCS affects every organ system, including the central nervous system. Neurological “long-haul” symptoms last from a few weeks to several months and include brain fog, chronic fatigue, dyspnea, mood dysregulation, and headaches. Data suggest that 10-30% of individuals testing positive for Covid-19 develop CCS. Current literature indicates a decreased quality of life in persistent symptoms. CCS is a pervasive and pernicious COVID-19 sequelae. More research is needed to understand risk factors, impact, and possible interventions. Research frequently cites cytokine storming as noteworthy etiology in CCS. Cytokine storming is a malfunctional immune response and facilitates multidimensional interconnected physiological responses. The most prominent responses include abnormal blood flow, hypoxia/hypoxemia, inflammation, and endothelial damage. Neurological impairments and pathogenesis in CCS parallel that of traumatic brain injury (TBI). Both exhibit impairments in memory, cognition, mood, sustained attention, and chronic fatigue. Evidence suggests abnormal blood flow, inflammation, and hypoxemia as shared causal factors. Cytokine storming is also typical in mTBI. The shared characteristics in symptoms and etiology suggest potential parallel routes of investigation that allow for better understanding of CCS. Research on the effect of altitude in mTBI varies. Literature finds decreased rates of concussions at higher altitudes. Other studies suggest that at a higher altitude, pre-existing mTBI symptoms are exacerbated. This may mean that in CCS, the geographical location where individuals live and the location where individuals experienced acute Covid-19 symptoms may influence the severity and risk of developing CCS. It also suggests that clinics which treat mTBI patients could also provide benefits for those with CCS. This study aims to examine the relationships between altitude and CCS as a risk factor and investigate the longevity and severity of symptoms in different altitudes. Existing patient data from a concussion clinic using fMRI scans and self-reported symptoms will be used for approximately 30 individuals with CCS symptoms. The association between acclimated altitude and CCS severity will be analyzed. Patients will be classified into low, medium, and high altitude groups and compared for differences on fMRI severity scores and self-reported measures. It is anticipated that individuals living in lower altitudes are at higher risk of developing more severe neuropsychological symptoms in CCS. It is also anticipated that a treatment approach for mTBI will also be beneficial to those with CCS.

Keywords: altitude, chronic covid syndrome, concussion, covid brain, EPIC treatment, fMRI, traumatic brain injury

Procedia PDF Downloads 118

Authors: Giulia Bonaldo, Alberto Vaccheri, Ottavio D'Annibali, Domenico Motola

Abstract:

The Human Papilloma Virus (HPV) was shown to be the cause of different types of carcinomas, first of all of the cervical intraepithelial neoplasia. Since the early 80s to today, thanks first to the preventive screening campaigns (pap-test) and following to the introduction of HPV vaccines on the market; the number of new cases of cervical cancer has decreased significantly. The HPV vaccines currently approved are three: Cervarix® (HPV2 - virus type: 16 and 18), Gardasil® (HPV4 - 6, 11, 16, 18) and Gardasil 9® (HPV9 - 6, 11, 16, 18, 31, 33, 45, 52, 58), which all protect against the two high-risk HPVs (6, 11) that are mainly involved in cervical cancers. Despite the remarkable effectiveness of these vaccines has been demonstrated, in the recent years, there have been many complaints about their risk-benefit profile due to Adverse Events Following Immunization (AEFI). The purpose of this study is to provide a support about the ongoing discussion on the safety profile of HPV vaccines based on real life data deriving from spontaneous reports of suspected AEFIs collected in the Vaccine Adverse Events Reporting System (VAERS). VAERS is a freely-available national vaccine safety surveillance database of AEFI, co-administered by the Centers for Disease Control and Prevention (CDC) and Food and Drug Administration (FDA). We collected all the reports between January 2007 to December 2017 related to the HPV vaccines with a brand name (HPV2, HPV4, HPV9) or without (HPVX). A disproportionality analysis using Reporting Odds Ratio (ROR) with 95% confidence interval and p value ≤ 0.05 was performed. Over the 10-year period, 54889 reports of AEFI related to HPV vaccines reported in VAERS, corresponding to 224863 vaccine-event pairs, were retrieved. The highest number of reports was related to Gardasil (n = 42244), followed by Gardasil 9 (7212) and Cervarix (3904). The brand name of the HPV vaccine was not reported in 1529 cases. The two events more frequently reported and statistically significant for each vaccine were: dizziness (n = 5053) ROR = 1.28 (CI95% 1.24 – 1.31) and syncope (4808) ROR = 1.21 (1.17 – 1.25) for Gardasil. For Gardasil 9, injection site pain (305) ROR = 1.40 (1.25 – 1.57) and injection site erythema (297) ROR = 1.88 (1.67 – 2.10) and for Cervarix, headache (672) ROR = 1.14 (1.06 – 1.23) and loss of consciousness (528) ROR = 1.71 (1.57 – 1.87). In total, we collected 406 reports of death and 2461 cases of permanent disability in the ten-year period. The events consisting of incorrect vaccine storage or incorrect administration were not considered. The AEFI analysis showed that the most frequently reported events are non-serious and listed in the corresponding SmPCs. In addition to these, potential safety signals arose regarding less frequent and severe AEFIs that would deserve further investigation. This already happened with the referral of the European Medicines Agency (EMA) for the adverse events POTS (Postural Orthostatic Tachycardia Syndrome) and CRPS (Complex Regional Pain Syndrome) associated with anti-papillomavirus vaccines.

Keywords: adverse drug reactions, pharmacovigilance, safety, vaccines

Procedia PDF Downloads 145

Authors: R. P. Hewawasam, M. H. A. D. de Silva, M. A. G. Iresha

Abstract:

Obesity is associated with an increased risk of developing insulin resistance. Insulin resistance often progresses to type-2 diabetes mellitus and is linked to a wide variety of other pathophysiological features including hypertension, hyperlipidemia, atherosclerosis (metabolic syndrome) and polycystic ovarian syndrome. Macrosomia is common in infants born to not only women with gestational diabetes mellitus but also non-diabetic obese women. During the past two decades, obesity in children and adolescents has risen significantly in Asian populations including Sri Lanka. There is increasing evidence to believe that infants who are born large for gestational age (LGA) are more likely to be obese in childhood. It is also established from previous studies that Asian populations have higher percentage body fat at a lower body mass index compared to Caucasians. High leptin levels in cord blood have been reported to correlate with fetal adiposity at birth. Previous studies have also shown that cord blood C-peptide and insulin levels are significantly and positively correlated with birth weight. Therefore, the objective of this preliminary study was to determine the relationship between parameters of fetal insulin resistance such as leptin, C-peptide and insulin and the birth weight of the newborn in a study population in Southern Sri Lanka. Umbilical cord blood was collected from 90 newborns and the concentration of insulin, leptin, and C-peptide were measured by ELISA technique. Birth weight, length, occipital frontal, chest, hip and calf circumferences of newborns were measured and characteristics of the mother such as age, height, weight before pregnancy and weight gain were collected. The relationship between insulin, leptin, C-peptide, and anthropometrics were assessed by Pearson’s correlation while the Mann-Whitney U test was used to assess the differences in cord blood leptin, C-peptide, and insulin levels between groups. A significant difference (p < 0.001) was observed between the insulin levels of infants born LGA (18.73 ± 0.64 µlU/ml) and AGA (13.08 ± 0.43 µlU/ml). Consistently, A significant increase in concentration (p < 0.001) was observed in C-peptide levels of infants born LGA (9.32 ± 0.77 ng/ml) compared to AGA (5.44 ± 0.19 ng/ml). Cord blood leptin concentration of LGA infants (12.67 ng/mL ± 1.62) was significantly higher (p < 0.001) compared to the AGA infants (7.10 ng/mL ± 0.97). Significant positive correlations (p < 0.05) were observed among cord leptin levels and the birth weight, pre-pregnancy maternal weight and BMI between the infants of AGA and LGA. Consistently, a significant positive correlation (p < 0.05) was observed between the birth weight and the C peptide concentration. Significantly high concentrations of leptin, C-peptide and insulin levels in the cord blood of LGA infants suggest that they may be involved in regulating fetal growth. Although previous studies suggest comparatively high levels of body fat in the Asian population, values obtained in this study are not significantly different from values previously reported from Caucasian populations. According to this preliminary study, maternal pre-pregnancy BMI and weight may contribute as significant indicators of cord blood parameters of insulin resistance and possibly the birth weight of the newborn.

Keywords: large for gestational age, leptin, C-peptide, insulin

Procedia PDF Downloads 143

Authors: Sanela Slavkovic, Congor Nad, Spela Golubovic

Abstract:

Background: The diagnosis of multiple sclerosis (MS) is a major life challenge and has repercussions on all aspects of the daily functioning of those attained by it – personal activities, social participation, and quality of life. Regular follow-up of only the neurological status is not informative enough so that it could provide data on the sort of support and rehabilitation that is required. Objective: The aim of this study was to establish the current level of functioning of persons attained by MS and the factors that influence it. Methods: The study was conducted in Serbia, on a sample of 108 persons with relapse-remitting form of MS, aged 20 to 53 (mean 39.86 years; SD 8.20 years). All participants were fully ambulatory. Methods applied in the study include Expanded Disability Status Scale-EDSS and World Health Organization Disability Assessment Schedule, WHODAS 2.0 (36-item version, self-administered). Results: Participants were found to experience the most problems in the domains of Participation, Mobility, Life activities and Cognition. The least difficulties were found in the domain of Self-care. Symptom duration was the only control variable with a significant partial contribution to the prediction of the WHODAS scale score (β=0.30, p < 0.05). The total EDSS score correlated with the total WHODAS 2.0 score (r=0.34, p=0.00). Statistically significant differences in the domain of EDSS 0-5.5 were found within categories (0-1.5; 2-3.5; 4-5.5). The more pronounced a participant’s EDSS score was, although not indicative of large changes in the neurological status, the more apparent the changes in the functional domain, i.e. in all areas covered by WHODAS 2.0. Pyramidal (β=0.34, p < 0.05) and Bowel and bladder (β=0.24, p < 0.05) functional systems were found to have a significant partial contribution to the prediction of the WHODAS score. Conclusion: Measuring functioning and disability is important in the follow-up of persons suffering from MS in order to plan rehabilitation and define areas in which additional support is needed.

Keywords: disability, functionality, multiple sclerosis, rehabilitation

Procedia PDF Downloads 103

Authors: Albert Alexander Stonier

Abstract:

Due to the fossil fuel exhaustion and environmental pollution, renewable energy sources especially solar photovoltaic system plays a predominant role in providing energy to the consumers. It has been estimated that by 2050 the renewable energy sources will satisfy 50% of the total energy requirement of the world. In this context, the faults in the conversion process require a special attention which is considered as a major problem. A fault which remains even for a few seconds will cause undesirable effects to the system. The presentation comprises of the analysis, causes, effects and mitigation methods of various faults occurring in the entire solar photovoltaic energy conversion process. In order to overcome the faults in the system, an intelligent based artificial neural networks and fuzzy logic are proposed which can significantly mitigate the faults. Hence the presentation intends to find the problem in renewable energy and provides the possible solution to overcome it with simulation and experimental results. The work performed in a 3kWp solar photovoltaic plant whose results cites the improvement in reliability, availability, power quality and fault tolerant ability.

Keywords: solar photovoltaic, power electronics, power quality, PWM

Procedia PDF Downloads 262

Authors: Nicholas Sehube, Rosemary Kelebemang, Pogisego Dinake

Abstract:

The extent of Pb contamination of shooting range soils has never been ascertained in Botswana, this was the first attempt in evaluating the deposition of Pb into the soils emanating from munitions. A total of 8 military shooting ranges were used for this study. Soil samples were collected at each of the 8 shooting ranges at the berm (stop butt), target line, 50 and 100 m from the berm. In all of the shooting ranges investigated the highest concentrations were found in the berm soils. The highest Pb concentrations of 38 406.87 mg/Kg were found in the berm soils of Thebephatshwa shooting range which is enclosed within a military camp with staff residential dwelling only a kilometre away. Most of the shooting ranges soils contained elevated levels of Pb in the ranges above 2000 mg/kg far exceeding the United States Environmental Protection Agency (USEPA) critical value of 400 mg/Kg. Mobilization of lead at high pH is attributed to low organic matter and such was the case with Thebephatshwa shooting range with a percept organic matter of 0.35±0.08. The predominant weathering products in these shooting ranges were cerussite (PbCO3), hydrocerussite (Pb(CO3)2(OH)2 and massicot (PbO). The detailed examination and characterization of the extent of pollution will help in the development and implementation of scientifically sound remediation and restoration of shooting ranges soils.

Keywords: ammunition, Botswana, Pb, pollution, soil

Procedia PDF Downloads 218

Authors: Mustafa Cam, Nedim Ongun, Ufuk Kutluana

Abstract:

Introduction: Restless LegsSyndrome (RLS) is a common, under-recognized disorder disrupts sleep and diminishes quality of life (1). The most common conditions highly associated with RLS include renalfailure, iron and folic acid deficiency, peripheral neuropathy, pregnancy, celiacdisease, Crohn’sdiseaseandrarelymalignancy (2).Despite a clear relation between low peripheral iron and increased prevalence and severity of RLS, the prevalence and clinical significance of RLS in iron-deficientanemic populations is unknown (2). We report here a case of RLS due to iron deficiency in the setting of neuroendocrinetumor. Report of Case: A 35 year-old man was referred to our clinic with general weakness, weight loss (10 kg in 2 months)and 2-month history of uncomfortable sensations in his legs with urge to move, partially relieved by movement. The symptoms were presented very day, worsening in the evening; the discomfort forced the patient to getup and walk around at night. RLS was severe, with a score of 22 at the International RLS ratingscale. The patient had no past medical history. The patient underwent a complete set of blood analyses and the following ab normal values were found (normal limitswithinbrackets): hemoglobin 9.9 g/dl (14-18), MCV 70 fL (80-94), ferritin 3,5 ng/mL (13-150). Brain and spinemagnetic resonance imaging was normal. The patient consultated with gastroenterology clinic and gastointestinal systemendoscopy was performed for theetiology of the iron deficiency anemia. After the gastricbiopsy, results allowed us to reach the diagnosis of neuroen docrine tumor and the patient referred to oncology clinic. Discussion: The first important consideration from this case report is that the patient was referred to our clinic because of his severe RLS symptoms dramatically reducing his quality of life. However, our clinical study clearly demonstrated that RLS was not the primary disease. Considering the information available for this patient, we believe that the most likely possibility is that RLS was secondary to iron deficiency, a very well-known and established cause of RLS in theliterature (3,4). Neuroendocrine tumors (NETs) are rare epithelial neoplasms with neuroendocrine differentiation that most commonly originate in the lungs and gastrointestinal tract (5). NETs vary widely in their clinical presentation; symptoms are often nonspecific and can be mistaken for those of other more common conditions (6). 50% of patients with reported disease stage have either regional or distant metastases at diagnosis (7). Accurate and earlier NET diagnosis is the first step in shortening the time to optimal care and improved outcomes for patients (8). The most important message from this case report is that RLS symptoms can sometimes be thesign of a life-threatening condition. Conclusion: Careful and complete collection of clinical and laboratory data should be carried out in RLS patients. Inparticular, if RLS onset coincides with weight loss and iron deficieny anemia, gastricendos copy should be performed. It is known about that malignancy is a rare etiology in RLS patients and to our knowledge; it is the first case with neuro endocrine tumor presenting with RLS.

Keywords: neurology, neuroendocrine tumor, restless legs syndrome, sleep

Procedia PDF Downloads 267

Authors: Ozcan Baris Citil

Abstract:

The aim of the present study is the determination of the effects of variations in the proximate analysis, cholesterol content and fatty acid compositions of Helix aspersa. Garden snails (Helix aspersa) were picked up by hand from the Central Anatolia Region of Turkey, in autumn (November) in 2015. Fatty acid methyl esters (FAMEs) and cholesterol analysis were analyzed by gas chromatography (GC). The protein contents of snail muscle were determined with Kjeldahl distillation units. Statistical comparisons were made by using SPSS Software (version 16.0). Thirty different fatty acids of different saturation levels were detected. As the predominant fatty acids, stearic acid (C18:0), oleic acid (C18:1ω9), linoleic acid (C18:2ω6), palmitic acid (C16:0), arachidonic acid (C20:4ω6), eicosadienoic acid (C20:2) and linolenic acid (C18:3ω3) were found in Helix aspersa. Palmitic acid (C16:0) was identified as the major SFA in autumn. Linoleic acid (C18:2ω6), eicosadienoic acid (C20:2) and arachidonic acid (C20:4ω6) have the highest levels among the PUFAs. In the present study, ω3 were found 5.48% in autumn. Linolenic acid and omega-3 fatty acid amounts in the autumn decreased significantly but cholesterol content was not affected in Helix aspersa in autumn (November) in 2015.

Keywords: Helix aspersa, fatty acid, SFA, PUFA, cholesterol

Procedia PDF Downloads 323

Authors: R. Komsa-Penkova, G. Golemanov, G. Georgieva, K. Popovski, N. Slavov, P. Ivanov, K. Kovacheva, S. Rathee, E. Konova, A. Blajev

Abstract:

Leptin and PAI-1 are important cytokines and may play a role in the regulation of PCOS development. PCOS is frequently associated with obesity, high BMI index and consequently with increased risk of metabolic disorders. The aim of the present study was to evaluate PAI-1 levels, genetic influence of the carriage of 675 4G/5G polymorphism in PAI-1 gene and leptin as a marker of obesity in the development of PCOS. Methods: Genotyping in 84 patients with PCOS and PCO and 100 healthy control subjects to detect single nucleotide deletion 675 G in the promoter of PAI-1 gene. The present study provides evidence that SNP 4G in the PAI-1 gene is associated with early pregnancy losses in patients with polycystosis. Further to this, there is a correlation between leptin levels, PAI-1 levels and BMI in the patients with PCOS, which confirms the role of obesity as a risk factor for PCOS.

Keywords: carriage of 675 4G/5G polymorphism, PCOS, early pregnancy losses, PAI-1 gene

Procedia PDF Downloads 318

Authors: D. Naresh Yadav, K. Anand Kishore, Bhaskar Bethi, Shirish H. Sonawane, D. Bhagawan

Abstract:

The untreated industrial wastewater discharged into the environment causes the contamination of soil, water and air. Advanced treatment methods for enhanced wastewater treatment are attracting substantial interest among the currently employed unit processes in wastewater treatment. The textile industry is one of the predominant in wastewater production at current industrialized situation. The refused dyes at textile industry need to be treated in proper manner before its discharge into water bodies. In the present investigation, hybrid treatment process has been developed for the treatment of synthetic mixed dye wastewater. Photocatalysis and ceramic nanoporous membrane are mainly used for process integration to minimize the fouling and increase the flux. Commercial semiconducting powders (TiO2 and ZnO) has used as a nano photocatalyst for the degradation of mixed dye in the hybrid system. Commercial ceramic nanoporous tubular membranes have been used for the rejection of dye and suspended catalysts. Photocatalysis with catalyst has shown the average of 34% of decolorization (RB-32%, BG-34% and CR-36%), whereas ceramic nanofiltration has shown the 56% (RB-54%, BG-56% and CR-58%) of decolorization. Integration of photocatalysis and ceramic nanofiltration has shown 96% (RB-94%, BG-96% and CR-98%) of dye decolorization over 90 min of operation.

Keywords: photocatalysis, ceramic nanoporous membrane, wastewater treatment, advanced oxidation process, process integration

Procedia PDF Downloads 244

Authors: Lesa A. Thompson, Yoshinori Ikenaka, Victor Wepener, Mayumi Ishizuka

Abstract:

One method for controlling malaria in endemic regions is the killing of vector mosquitoes using pesticides such as DDT in indoor residual spraying (IRS). This study was carried out to investigate the presence of and human health risk due to DDT and its metabolites (collectively, DDTs) contaminating human food sources in areas where DDT is used for IRS. Free-range chicken products (meat and eggs) were collected from homesteads in KwaZulu-Natal Province in the northeast of South Africa, and fish meat samples from Maputo Bay in neighbouring Mozambique. Samples were analysed for DDTs (o,p’-DDT, p,p’-DDT, o,p’-DDD, p,p’-DDD, o,p’-DDE and p,p’-DDE) using a gas chromatograph with electron capture detector (GC-ECD). DDTs were detected in all food types, with the predominant congener being p,p’-DDE. The presence of p,p’-DDT confirmed recent release of DDT into the environment. By using concentration levels detected in foods and national consumption levels, the risk to human health through consumption of such food products was calculated. In order of risk level, these were: chicken eggs > chicken meat > fish meat. Human risk (carcinogenic) values greater than one suggest there is an increased health risk through consumption of these foods.

Keywords: DDT, food contamination, human health risk, Mozambique, South Africa

Procedia PDF Downloads 322

Authors: Natcha Lueangapapong, Chariya Chuthapisith, Lunliya Thampratankul

Abstract:

Background: There is a need to find an appropriate tool to help healthcare providers determine sleep problems in children for early diagnosis and management. The Japanese Sleep Questionnaire for Preschoolers (JSQ-P) is a parent-reported sleep questionnaire that has good psychometric properties and can be used in the context of Asian culture, which is likely suitable for Thai children. Objectives: This study aimed to translate and validate the Japanese Sleep Questionnaire for Preschoolers (JSQ-P) into a Thai version and to evaluate factors associated with sleep disorders in preschoolers. Methods: After approval by the original developer, the cross-cultural adaptation process of JSQ-P was performed, including forward translation, reconciliation, backward translation, and final approval of the Thai version of JSQ-P (TH-JSQ-P) by the original creator. This study was conducted between March 2021 and February 2022. The TH-JSQ-P was completed by 2,613 guardians whose children were aged 2-6 years twice in 10-14 days to assess its reliability and validity. Content validity was measured by an index of item-objective congruence (IOC) and a content validity index (CVI). Face validity, content validity, structural validity, construct validity (discriminant validity), criterion validity and predictive validity were assessed. The sensitivity and specificity of the TH-JSQ-P were also measured by using a total JSQ-P score cutoff point 84, recommended by the original JSQ-P and each subscale score among the clinical samples of obstructive sleep apnea syndrome. Results: Internal consistency reliability, evaluated by Cronbach’s α coefficient, showed acceptable reliability in all subscales of JSQ-P. It also had good test-retest reliability, as the intraclass correlation coefficient (ICC) for all items ranged between 0.42-0.84. The content validity was acceptable. For structural validity, our results indicated that the final factor solution for the Th-JSQ-P was comparable to the original JSQ-P. For construct validity, age group was one of the clinical parameters associated with some sleep problems. In detail, parasomnias, insomnia, daytime excessive sleepiness and sleep habits significantly decreased when the children got older; on the other hand, insufficient sleep was significantly increased with age. For criterion validity, all subscales showed a correlation with the Epworth Sleepiness Scale (r = -0.049-0.349). In predictive validity, the Epworth Sleepiness Scale was significantly a strong factor that correlated to sleep problems in all subscales of JSQ-P except in the subscale of sleep habit. The sensitivity and specificity of the total JSQ-P score were 0.72 and 0.66, respectively. Conclusion: The Thai version of JSQ-P has good internal consistency reliability and test-retest reliability. It passed 6 validity tests, and this can be used to evaluate sleep problems in preschool children in Thailand. Furthermore, it has satisfactory general psychometric properties and good reliability and validity. The data collected in examining the sensitivity of the Thai version revealed that the JSQ-P could detect differences in sleep problems among children with obstructive sleep apnea syndrome. This confirmed that the measure is sensitive and can be used to discriminate sleep problems among different children.

Keywords: preschooler, questionnaire, validation, Thai version

Procedia PDF Downloads 73

Authors: Monette S. De Castro, Veneranda A. Magpantay, Christine B. Adiova, Mark D. Arboleda

Abstract:

One-hundred-layer chicken farmers were randomly selected and interviewed using structured questionnaires to assess the production system and management practices in layer chicken farms. The respondents belonged to the commercial scale operation. Results showed that the predominant rearing and housing systems were intensive/complete confinement and open-sided, while slatted was the common type of flooring used during the brood-grow period. Dekalb and Lohmann were the common chicken layer strains reared by farmers. The majority of commercial chicken layer farms preferred ready-to-lay (RTL) pullets as their replacement stocks. Selling was the easiest way for farmers to dispose of and utilize poultry manure, while veterinary waste and mortality were disposed of in pits. Biosecurity practices employed by the farmers conformed with the ASEAN Biosecurity Management Manual for Commercial Poultry Farming. Flies and odor were the major problems in most layer farms that are associated with their farm wastes. Therefore, the application of new technologies and husbandry practices through training and actual demonstrations could be implemented to further improve the layer chicken raising in the province.

Keywords: layer chicken farms, marketing, production system, waste management

Procedia PDF Downloads 46

Authors: Jenny Fairthorne, Yuka Mori, Helen Leonard

Abstract:

Background: Primary care-givers of children with autism spectrum disorder (ASD) or intellectual disability (ID) have poorer health and quality of life (QoL) than primary care-givers (hereafter referred to as just care-givers) of typically developing children. We aimed to review original research which described factors impacting the health of care-givers of children with ASD or ID and to discuss how these factors might influence care-giver health. Methods: We searched Web of Knowledge, Medline, Scopus and Google Scholar using selections of words from each of three groups. The first comprised terms associated with ASD and ID and included autism, pervasive development disorder, intellectual disability, mental retardation, disability, disabled, Down and Asperger. The second included terms related to health such as depression, physical, mental, psychiatric, psychological and well-being. The third was terms related to care-givers such as mother, parent and care-giver. We included an original paper in our review if it was published between 1st January 1990 and 31st December, 2016, described original research in a peer-reviewed journal and was written in English. Additional criteria were that the research used a study population of 15 persons or more; described a risk or protective factor for the health of care-givers of a child with ASD, ID or a sub-type (such as ASD with ID or Down syndrome). Using previous research, we developed a simple and objective five-level tool to assess the strength of evidence provided by the reviewed papers. Results: We retained 33 papers. Factors impacting primary care-giver health included child behaviour, level of support, socio-economic status (SES) and diagnostic issues. Challenging child behaviour, the most commonly identified risk factor for poorer care-giver health and QoL was reported in ten of the studies. A higher level of support was associated with improved care-giver health and QoL. For example, substantial evidence indicated that family support reduced care-giver burden in families with a child with ASD and that family and neighbourhood support was associated with improved care-giver mental health. Higher socio-economic status (SES) was a protective factor for care-giver health and particularly maternal health. Diagnostic uncertainty and an unclear prognosis are factors which can cause the greatest concern to care-givers of children with ASD and those for whom a cause of their child’s ID has not been identified. We explain how each of these factors might impact caregiver health and how they might act differentially in care-givers of children with different types of ASD or ID (such as Down syndrome and ASD without ID). Conclusion: Care-givers of children with ASD may be more likely to experience many risk factors and less likely to experience the protective factors we identified for poorer mental health. Interventions to reduce risk factors and increase protective factors could pave the way for improved care-giver health. For example, workshops to train care-givers to better manage challenging child behaviours and earlier diagnosis of ASD (and particularly ASD without ID) would seem likely to improve care-giver well-being. Similarly, helping to expand support networks might reduce care-giver burden and stress leading to improved health.

Keywords: autism, caregivers, health, intellectual disability, mothers, review

Procedia PDF Downloads 145

Authors: Monique M. Keller, Roline Barnes, Corlia Brandt

Abstract:

Introduction Scientific evidence on the hand forces and the types of grasps measurement during daily tasks are lacking, leaving a gap in the field of hand rehabilitation and robotics. Measuring the grasp forces and types produced by the individual fingers during daily functional tasks is valuable to inform and grade rehabilitation practices for second to fifth metacarpal fractures with robust scientific evidence. Feix et al, 2016 identified the most extensive and complete grasp study that resulted in the GRASP taxonomy. Covid-19 virus changed data collection across the globe and safety precautions in research are essential to ensure the health of participants and researchers. Methodology A cross-sectional study investigated six healthy adults aged 20 to 59 years, pilot participants’ hand forces during 105 tasks. The tasks were categorized into five sections namely, personal care, transport and moving around, home environment and inside, gardening and outside, and office. The predominant grasp of each task was identified guided by the GRASP Taxonomy. Grasp forces were measured with 13mm force-sensing resistors glued onto a glove attached to each of the dominant and non-dominant hand’s individual fingers. Testing equipment included Flexiforce 13millimetres FSR .5" circle, calibrated prior to testing, 10k 1/4w resistors, Arduino pro mini 5.0v – compatible, Esp-01-kit, Arduino uno r3 – compatible board, USB ab cable - 1m, Ftdi ft232 mini USB to serial, Sil 40 inline connectors, ribbon cable combo male header pins, female to female, male to female, two gloves, glue to attach the FSR to glove, Arduino software programme downloaded on a laptop. Grip strength measurements with Jamar dynamometer prior to testing and after every 25 daily tasks were taken to will avoid fatigue and ensure reliability in testing. Covid-19 precautions included wearing face masks at all times, screening questionnaires, temperatures taken, wearing surgical gloves before putting on the testing gloves 1.5 metres long wires attaching the FSR to the Arduino to maintain social distance. Findings Predominant grasps observed during 105 tasks included, adducted thumb (17), lateral tripod (10), prismatic three fingers (12), small diameter (9), prismatic two fingers (9), medium wrap (7), fixed hook (5), sphere four fingers (4), palmar (4), parallel extension (4), index finger extension (3), distal (3), power sphere (2), tripod (2), quadpod (2), prismatic four fingers (2), lateral (2), large-diameter (2), ventral (2), precision sphere (1), palmar pinch (1), light tool (1), inferior pincher (1), and writing tripod (1). Range of forces applied per category, personal care (1-25N), transport and moving around (1-9 N), home environment and inside (1-41N), gardening and outside (1-26.5N), and office (1-20N). Conclusion Scientifically measurements of finger forces with careful consideration to types of grasps used in daily tasks should guide rehabilitation practices and robotic design to ensure a return to the full participation of the individual into the community.

Keywords: activities of daily living (ADL), Covid-19, force-sensing resistors, grasps, hand forces

Procedia PDF Downloads 178

Authors: Moushira Zaki, Wafaa Ezzat, Yasser Elhosary, Omnia Saleh

Abstract:

Nonalcoholic fatty liver disease (NAFLD) has increased in conjunction with obesity. The accuracy of risk factors for detecting NAFLD in obese adolescents has not undergone a formal evaluation. The aim of this study was to evaluate predictors of NAFLD among Egyptian female obese adolescents. The study included 162 obese female adolescents. All were subjected to anthropometry, biochemical analysis and abdominal ultrasongraphic assessment. Metabolic syndrome (MS) was diagnosed according to the IDF criteria. Significant association between presence of MS and NAFLD was observed. Obese adolescents with NAFLD had significantly higher levels of ALT, triglycerides, fasting glucose, insulin, blood pressure and HOMA-IR, whereas decreased HDL-C levels as compared with obese cases without NAFLD. Receiver–operating characteristic (ROC) curve analysis shows that ALT is a sensitive predictor for NAFLD, confirming that ALT can be used as a marker of NAFLD.

Keywords: obesity, NAFLD, predictors, adolescents, Egyptians, risk factors, prevalence

Procedia PDF Downloads 365

Authors: Fatma Ismailia, Malek Saihi

Abstract:

This research provides an explanation of exchange incentives on the Tunis stock market from a behavioural point of view. The elucidation of the anomalies of excessive volume of transactions and that of excessive volatility cannot be done without the recourse to the psychological aspects of investors. The excessive confidence has been given the predominant role for the explanation of these phenomena. Indeed, when investors store increments, they become more confident about the precision of their private information and their exchange activities then become more aggressive on the subsequent periods. These overconfident investors carry out the intensive exchanges leading to an increase of securities volatility. The objective of this research is to identify whether the trading volume and the excessive volatility of securities observed on the Tunisian stock market come from the excessive exchange of overconfident investors. We use a sample of daily observations over the period January 1999 - October 2007 and we relied on various econometric tests including the VAR model. Our results provide evidence on the importance to consider the bias of overconfidence in the analysis of Tunis stock exchange specificities. The results reveal that the excess of confidence has a major impact on the trading volume while using daily temporal intervals.

Keywords: overconfidence, trading volume, efficiency, rationality, anomalies, behavioural finance, cognitive biases

Procedia PDF Downloads 396

Authors: Md. Salim Kaiser

Abstract:

In the present work, the effect of load and sliding distance on the performance tribology of commercially used aluminium-silicon engine block and piston was evaluated at ambient conditions with humidity of 80% under dry sliding conditions using a pin-on-disc with two different loads of 5N and 20N yielding applied pressure of 0.30MPa and 1.4MPa, respectively, at sliding velocity of 0.29ms-1 and with varying sliding distance ranging from 260m-4200m. Factors and conditions that had significant effect were identified. The results showed that the load and the sliding distance affect the wear rate of the alloys and the wear rate increased with increasing load for both the alloys. Wear rate also increases almost linearly at low loads and increase to a maximum then attain a plateau with increasing sliding distance. For both applied loads, the piston alloy showed the better performance due to higher Ni and Mg content. The worn surface and wear debris was characterized by optical microscope, SEM and EDX analyzer. The worn surface was characterized by surface with shallow grooves at loads while the groove width and depth increased as the loads increases. Oxidative wear was found to be the predominant mechanisms in the dry sliding of Al-Si alloys at low loads

Keywords: wear, friction, gravimetric analysis, aluminium-silicon alloys, SEM, EDX

Procedia PDF Downloads 240