Search results for: heart rate variability (HRV)
9127 Effect of Perioperative Protocol of Care on Clinical Outcomes among Patients Undergoing Coronary Artery Bypass Graft
Authors: Manal Ahmed, Amal Shehata, Shereen Deeb
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The study's purpose was to determine the effect of the perioperative protocol of care on clinical outcomes among patients undergoing coronary artery bypass graft. Subjects: A sample of 100 adult patients who were planned for coronary artery bypass graft, were selected and divided alternatively and randomly into two equal groups (50 study -50 control).The study was carried out at National heart Institute in Cairo and open heart surgical intensive care unit in Shebin El-Kom Teaching Hospital. Instruments: Four instruments were used for data collection: Interviewing questionnaire, dyspnea analogue scale, Biophysiological measurement instrument, and Compliance assessment sheet. Results: There were statistically significant differences between both groups regarding most respiratory system assessment findings at discharge. More than two-thirds of the study group of the current study had a continuous and regular commitment to diet regimen, which ranked first followed by the compliance of daily living activities then quitting smoking. Conclusions: The perioperative protocol of care has a significant improving effect on respiratory findings, dyspnea degree, duration of mechanical ventilation, length of hospital stay, compliance to diet, therapeutic regimen, daily living activities, and quit smoking among study group undergoing CABG. Recommendations: Perioperative protocol of care should be carried out for CABG patients at open-heart surgical units as well as an illustrative colored booklet about CAD, CABG and perioperative care should be available and distributed to all CABG patients.Keywords: perioperative, effect, clinical outcomes, coronary artery, bypass graft, protocol of care
Procedia PDF Downloads 1399126 Assessment of Genetic Variability of Potato Genotypes for Proline Under Salt Stress Conditions
Authors: Elchin Hajiyev, Afet Memmedova Dadash, Sabina Hajiyeva, Aynur Karimova, Ramiz Aliyev
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Although potatoes have a wide distribution range, the yield potential of varieties varies greatly depending on the region. Our country is made up of agricultural regions with very different environmental characteristics.In this case, we cannot expect the introduced varieties to show the same adaptation to the different conditions of our country. For this reason, in our country, varieties with high general adaptability should be used, rather than varieties with special adaptability in certain areas. Soil salinization has become a global problem.Increased salinity has a serious impact on food security by reducing plant productivity. Plants have protective mechanisms of adaptation to salt stress, such as the synthesis of physiologically active substances, resistance to antioxidant stress and oxidation of membrane lipids. One of these substances is free proline. Our study revealed genetic variation in proline accumulation among samples exposed to stress factors.Changes in proline content under stress conditions were studied in 50 samples. There was wide variation across all treatments.The amount of proline varied between 7.2–37.7 μM/g under salinity conditions.The lowest rate was in the SF33 genotype (1.5 times more than the control (2.5 μM/g)).The highest level of proline under the influence of salt stress was in the SF45 genotype (7.25 times higher than the control (32.5 μM/g)). Our studies have found that the protective system reacts differently to the influence of stress factors. According to the results obtained on the amount of proline, adaptation mechanisms must be more actively activated to maintain metabolism and ensure viability in sensitive forms under the influence of stress factors. At high doses of the salt stressor, a tenfold increase in proline compared to the control indicates significant damage to the plant organism as a result of stress.To prevent damage to the body, the antioxidant system needs to quickly mobilize and work at full capacity in adverse conditions. An increase in the dose of the stress factor salt in our study caused a greater increase in the amount of free proline in plant tissues. Considering the functions of proline as an osmoprotector and antioxidant, it was found that increasing its amount is aimed at protecting the plant from the acute effects of stressors.Keywords: genetic variability, potato, genotypes, proline, stress
Procedia PDF Downloads 539125 Effect of Cardio-Specific Overexpression of MUL1, a Mitochondrial Protein on Myocardial Function
Authors: Ximena Calle, Plinio Cantero-López, Felipe Muñoz-Córdova, Mayarling-Francisca Troncoso, Sergio Lavandero, Valentina Parra
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MUL1, a mitochondrial E3 ubiquitin ligase anchored to the outer mitochondrial membrane, is highly expressed in the heart. MUL1 is involved in multiple biological pathways associated with mitochondrial dynamics. Increased MUL1 affects the balance between fission and fusion, affecting mitochondrial function, which plays a crucial role in myocardial function. Therefore, it is interesting to evaluate the effect of cardiac-specific overexpression of MUL1 on myocardial function. Aim: To determine heart functionality in a mouse model with cardio-specific overexpression MUL1 protein. Methods and Results: Male C57BL/Tg transgenic mice with cardiomyocyte-specific overexpression of MUL1 (n=10) and control (n=4) were evaluated at 12, 27, and 35 weeks of age. Glucose tolerance curve determination was performed after a 6-hours fast to assess metabolic capacity, treadmill test, and systolic, and diastolic pressure was evaluated by the mouse tail-cuff blood pressure system equipment. The result showed no glucose tolerance curve, and the treadmill test demonstrated no significant changes between groups. However, substantial changes in diastolic function were observed by ultrasound and determination of cardiac hypertrophy proteins by western blot. Conclusions: Cardio-specific overexpression of MUL1 in mice without any treatment affects diastolic cardiac function, thus showing the important role contributed by MUL1 in the heart. Future research should evaluate the effect of cardiomyocyte-specific overexpression of MUL1 in pathological conditions such as a high-fat diet is one of the main risk factors for cardiovascular disease.Keywords: diastolic dysfunction, hypertrophy cardiac, mitochondrial E3 ubiquitin ligase 1, MUL1
Procedia PDF Downloads 749124 An Unusual Cause of Electrocardiographic Artefact: Patient's Warming Blanket
Authors: Sanjay Dhiraaj, Puneet Goyal, Aditya Kapoor, Gaurav Misra
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In electrocardiography, an ECG artefact is used to indicate something that is not heart-made. Although technological advancements have produced monitors with the potential of providing accurate information and reliable heart rate alarms, despite this, interference of the displayed electrocardiogram still occurs. These interferences can be from the various electrical gadgets present in the operating room or electrical signals from other parts of the body. Artefacts may also occur due to poor electrode contact with the body or due to machine malfunction. Knowing these artefacts is of utmost importance so as to avoid unnecessary and unwarranted diagnostic as well as interventional procedures. We report a case of ECG artefacts occurring due to patient warming blanket and its consequences. A 20-year-old male with a preoperative diagnosis of exstrophy epispadias complex was posted for surgery under epidural and general anaesthesia. Just after endotracheal intubation, we observed nonspecific ECG changes on the monitor. At a first glance, the monitor strip revealed broad QRs complexes suggesting a ventricular bigeminal rhythm. Closer analysis revealed these to be artefacts because although the complexes were looking broad on the first glance there was clear presence of normal sinus complexes which were immediately followed by 'broad complexes' or artefacts produced by some device or connection. These broad complexes were labeled as artefacts as they were originating in the absolute refractory period of the previous normal sinus beat. It would be physiologically impossible for the myocardium to depolarize so rapidly as to produce a second QRS complex. A search for the possible reason for the artefacts was made and after deepening the plane of anaesthesia, ruling out any possible electrolyte abnormalities, checking of ECG leads and its connections, changing monitors, checking all other monitoring connections, checking for proper grounding of anaesthesia machine and OT table, we found that after switching off the patient’s warming apparatus the rhythm returned to a normal sinus one and the 'broad complexes' or artefacts disappeared. As misdiagnosis of ECG artefacts may subject patients to unnecessary diagnostic and therapeutic interventions so a thorough knowledge of the patient and monitors allow for a quick interpretation and resolution of the problem.Keywords: ECG artefacts, patient warming blanket, peri-operative arrhythmias, mobile messaging services
Procedia PDF Downloads 2739123 Effect of Saturation and Deformation Rate on Split Tensile Strength for Various Sedimentary Rocks
Authors: D. K. Soni
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A study of engineering properties of stones, i.e. compressive strength, tensile strength, modulus of elasticity, density, hardness were carried out to explore the possibility of optimum utilization of stone. The laboratory test results on equally dimensioned discs of the stone show a considerable variation in computed split tensile strength with varied rates of deformation. Hence, the effect of strain rate on the tensile strength of a sand stone and lime stone under wet and dry conditions has been studied experimentally using the split tensile strength test technique. It has been observed that the tensile strength of these stone is very much dependent on the rate of deformation particularly in a dry state. On saturation the value of split tensile strength reduced considerably depending upon the structure of rock and amount of water absorption.Keywords: sedimentary rocks, split tensile test, deformation rate, saturation rate, sand stone, lime stone
Procedia PDF Downloads 4119122 Methods of Interpolating Temperature and Rainfall Distribution in Northern Vietnam
Authors: Thanh Van Hoang, Tien Yin Chou, Yao Min Fang, Yi Min Huang, Xuan Linh Nguyen
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Reliable information on the spatial distribution of annual rainfall and temperature is essential in research projects relating to urban and regional planning. This research presents results of a classification of temperature and rainfall in the Red River Delta of northern Vietnam based on measurements from seven meteorological stations (Ha Nam, Hung Yen, Lang, Nam Dinh, Ninh Binh, Phu Lien, Thai Binh) in the river basin over a thirty-years period from 1982-2011. The average accumulated rainfall trends in the delta are analysed and form the basis of research essential to weather and climate forecasting. This study employs interpolation based on the Kriging Method for daily rainfall (min and max) and daily temperature (min and max) in order to improve the understanding of sources of variation and uncertainly in these important meteorological parameters. To the Kriging method, the results will show the different models and the different parameters based on the various precipitation series. The results provide a useful reference to assist decision makers in developing smart agriculture strategies for the Red River Delta in Vietnam.Keywords: spatial interpolation method, ArcGIS, temperature variability, rainfall variability, Red River Delta, Vietnam
Procedia PDF Downloads 3319121 Comparison of Cardiomyogenic Potential of Amniotic Fluid Mesenchymal Stromal Cells Derived from Normal and Isolated Congenital Heart Defective Fetuses
Authors: Manali Jain, Neeta Singh, Raunaq Fatima, Soniya Nityanand, Mandakini Pradhan, Chandra Prakash Chaturvedi
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Isolated Congenital Heart Defect (ICHD) is the major cause of neonatal death worldwide among all forms of CHDs. A significant proportion of fetuses with ICHD die in the neonatal period if no treatment is provided. Recently, stem cell therapies have emerged as a potential approach to ameliorate ICHD in children. ICHD is characterized by cardiac structural abnormalities during embryogenesis due to alterations in the cardiomyogenic properties of a pool of cardiac progenitors/ stem cells associated with fetal heart development. The stem cells present in the amniotic fluid (AF) are of fetal origin and may reflect the physiological and pathological changes in the fetus during embryogenesis. Therefore, in the present study, the cardiomyogenic potential of AF-MSCs derived from fetuses with ICHD (ICHD AF-MSCs) has been evaluated and compared with that of AF-MSCs of structurally normal fetuses (normal AF-MSCs). Normal and ICHD AF-MSC were analyzed for the expression of cardiac progenitor markers viz., stage-specific embryonic antigen-1 (SSEA-1), vascular endothelial growth factor 2 (VEGFR-2) and platelet-derived growth factor receptor-alpha (PDGFR-α) by flow cytometry. The immunophenotypic characterization revealed that ICHD AF-MSCs have significantly lower expression of cardiac progenitor markers VEGFR-2 (0.14% ± 0.6 vs.48.80% ± 0.9; p <0.01), SSEA-1 (70.86% ± 2.4 vs. 88.36% ±2.7; p <0.01), and PDGFR-α (3.92% ± 1.8 vs. 47.59% ± 3.09; p <0.01) in comparison to normal AF-MSCs. Upon induction with 5’-azacytidine for 21 days, ICHD AF-MSCs showed a significantly down-regulated expression of cardiac transcription factors such as GATA-4 (0.4 ± 0.1 vs. 6.8 ± 1.2; p<0.01), ISL-1 (2.3± 0.6 vs. 14.3 ± 1.12; p<0.01), NK-x 2-5 (1.1 ± 0.3 vs. 14.1 ±2.8; p<0.01), TBX-5 (0.4 ± 0.07 vs. 4.4 ± 0.3; p<0.001), and TBX-18 (1.3 ± 0.2 vs. 4.19 ± 0.3; p<0.01) when compared with the normal AF-MSCs. Furthermore, immunocytochemical staining revealed that both types of AF-MSCs could differentiate into cardiovascular lineages and express cardiomyogenic, endothelial, and smooth muscle actin markers, viz., cardiac troponin (cTNT), CD31, and alpha-smooth muscle actin (α-SMA). However, normal AF-MSCs showed an enhanced expression of cTNT (p<0.001), CD31 (p<0.01), and α-SMA (p<0.05), compared to ICHD AF-MSCs. Overall, these results suggest that the ICHD-AF-MSCs have a defective cardiomyogenic differentiation potential and that the defects in these stem cells may have a role in the pathogenesis of ICHD.Keywords: amniotic fluid, cardiomyogenic potential, isolated congenital heart defect, mesenchymal stem cells
Procedia PDF Downloads 1039120 Fluidised Bed Gasification of Multiple Agricultural Biomass-Derived Briquettes
Authors: Rukayya Ibrahim Muazu, Aiduan Li Borrion, Julia A. Stegemann
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Biomass briquette gasification is regarded as a promising route for efficient briquette use in energy generation, fuels and other useful chemicals, however, previous research work has focused on briquette gasification in fixed bed gasifiers such as updraft and downdraft gasifiers. Fluidised bed gasifier has the potential to be effectively sized for medium or large scale. This study investigated the use of fuel briquettes produced from blends of rice husks and corn cobs biomass residues, in a bubbling fluidised bed gasifier. The study adopted a combination of numerical equations and Aspen Plus simulation software to predict the product gas (syngas) composition based on briquette's density and biomass composition (blend ratio of rice husks to corn cobs). The Aspen Plus model was based on an experimentally validated model from the literature. The results based on a briquette size of 32 mm diameter and relaxed density range of 500 to 650 kg/m3 indicated that fluidisation air required in the gasifier increased with an increase in briquette density, and the fluidisation air showed to be the controlling factor compared with the actual air required for gasification of the biomass briquettes. The mass flowrate of CO2 in the predicted syngas composition, increased with an increase in the air flow rate, while CO production decreased and H2 was almost constant. The H2/CO ratio for various blends of rice husks and corn cobs did not significantly change at the designed process air, but a significant difference of 1.0 for H2/CO ratio was observed at higher air flow rate, and between 10/90 to 90/10 blend ratio of rice husks to corn cobs. This implies the need for further understanding of biomass variability and hydrodynamic parameters on syngas composition in biomass briquette gasification.Keywords: aspen plus, briquettes, fluidised bed, gasification, syngas
Procedia PDF Downloads 4589119 Determination of the Thermally Comfortable Air Temperature with Consideration of Individual Clothing and Activity as Preparation for a New Smart Home Heating System
Authors: Alexander Peikos, Carole Binsfeld
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The aim of this paper is to determine a thermally comfortable air temperature in an automated living room. This calculated temperature should serve as input for a user-specific and dynamic heating control in such a living space. In addition to the usual physical factors (air temperature, humidity, air velocity, and radiation temperature), individual clothing and activity should be taken into account. The calculation of such a temperature is based on different methods and indices which are usually used for the evaluation of the thermal comfort. The thermal insulation of the worn clothing is determined with a Radio Frequency Identification system. The activity performed is only taken into account indirectly through the generated heart rate. All these methods are ultimately very well suited for use in temperature regulation in an automated home, but still require further research and extensive evaluation.Keywords: smart home, thermal comfort, predicted mean vote, radio frequency identification
Procedia PDF Downloads 1599118 Comparison of the Logistic and the Gompertz Growth Functions Considering a Periodic Perturbation in the Model Parameters
Authors: Avan Al-Saffar, Eun-Jin Kim
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Both the logistic growth model and the gompertz growth model are used to describe growth processes. Both models driven by perturbations in different cases are investigated using information theory as a useful measure of sustainability and the variability. Specifically, we study the effect of different oscillatory modulations in the system's parameters on the evolution of the system and Probability Density Function (PDF). We show the maintenance of the initial conditions for a long time. We offer Fisher information analysis in positive and/or negative feedback and explain its implications for the sustainability of population dynamics. We also display a finite amplitude solution due to the purely fluctuating growth rate whereas the periodic fluctuations in negative feedback can lead to break down the system's self-regulation with an exponentially growing solution. In the cases tested, the gompertz and logistic systems show similar behaviour in terms of information and sustainability although they develop differently in time.Keywords: dynamical systems, fisher information, probability density function (pdf), sustainability
Procedia PDF Downloads 4339117 Information Communication Technology in Early Childhood Education: An Assessment of the Quality of ICT in the New Mega Primary Schools in Ondo State, Southwestern Nigeria
Authors: Oluyemi Christianah Ojo
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This study seeks to investigate the quality of ICT provided in the new Caring Heart schools in Ondo State, Nigeria. The population for the study was all caring Heart Mega Schools in Ondo State, Nigeria. Research questions were generated; two instruments CCCMS and TQCUC were used to elicit information from the schools and the teachers. The study adopts descriptive survey approach. The studies revealed and concluded that ICT components were available and adequate in these schools, Charts showing ICT components and other forms of computer devices used as instructional materials were available but were not adequate; teachers teaching computer studies are competent in the delivery of instructions and in handling computer gadgets in the laboratory. The study recommended the provision of steady electricity, uninterrupted internet facilities and provision of adequate ICT components and charts for effective teaching delivery and learning.Keywords: facilities, information communication technology, mega primary school, primary education
Procedia PDF Downloads 2979116 Exercise in Extreme Conditions: Leg Cooling and Fat/Carbohydrate Utilization
Authors: Anastasios Rodis
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Background: Case studies of walkers, climbers, and campers exposed to cold and wet conditions without limb water/windproof protection revealed experiences of muscle weakness and fatigue. It is reasonable to assume that a part of the fatigue could occur due to an alteration in substrate utilization, since reduction of performance in extreme cold conditions, may partially be explained by higher anaerobic glycolysis, reflecting higher carbohydrate oxidation and an increase accumulation rate of blood lactate. The aim of this study was to assess the effects of pre-exercise lower limb cooling on substrate utilization rate during sub-maximal exercise. Method: Six male university students (mean (SD): age, 21.3 (1.0) yr; maximal oxygen uptake (V0₂ max), 49.6 (3.6) ml.min⁻¹; and percentage of body fat, 13.6 (2.5) % were examined in random order after either 30min cold water (12°C) immersion utilized as the cooling strategy up to the gluteal fold, or under control conditions (no precooling), with tests separated by minimum of 7 days. Exercise consisted of 60min cycling at 50% V0₂ max, in a thermoneutral environment of 20°C. Subjects were also required to record a diet diary over the 24hrs prior to the each trial. Means (SD) for the three macronutrients during the 1 day prior to each trial (expressed as a percentage of total energy) 52 (3) % carbohydrate, 31 (4) % fat, and 17 (± 2) % protein. Results: The following responses to lower limb cooling relative to control trial during exercise were: 1) Carbohydrate (CHO) oxidation, and blood lactate (Bₗₐc) concentration were significantly higher (P < 0.05); 2) rectal temperature (Tᵣₑc) was significantly higher (P < 0.05), but skin temperature was significantly lower (P < 0.05); no significant differences were found in blood glucose (Bg), heart rate (HR) and oxygen consumption (V0₂). Discussion: These data suggested that lower limb cooling prior to submaximal exercise will shift metabolic processes from Fat oxidation to CHO oxidation. This shift from Fat to CHO oxidation will probably have important implications in the surviving scenario, since people facing accidental localized cooling of their limbs either through wading/falling in cold water or snow even if they do not perform high intensity activity, they have to rely on CHO availability.Keywords: exercise in wet conditions, leg cooling, outdoors exercise, substrate utilization
Procedia PDF Downloads 4409115 Wet Sliding Wear and Frictional Behavior of Commercially Available Perspex
Authors: S. Reaz Ahmed, M. S. Kaiser
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The tribological behavior of commercially used Perspex was evaluated under dry and wet sliding condition using a pin-on-disc wear tester with different applied loads ranging from 2.5 to 20 N. Experiments were conducted with varying sliding distance from 0.2 km to 4.6 km, wherein the sliding velocity was kept constant, 0.64 ms-1. The results reveal that the weight loss increases with applied load and the sliding distance. The nature of the wear rate was very similar in both the sliding environments in which initially the wear rate increased very rapidly with increasing sliding distance and then progressed to a slower rate. Moreover, the wear rate in wet sliding environment was significantly lower than that under dry sliding condition. The worn surfaces were characterized by optical microscope and SEM. It is found that surface modification has significant effect on sliding wear performance of Perspex.Keywords: Perspex, wear, friction, SEM
Procedia PDF Downloads 2749114 Exploitation of Variability for Salinity Tolerance in Maize Hybrids (Zea Mays L.) at Early Growth Stage
Authors: Abdul Qayyum, Hafiz Muhammad Saeed, Mamoona Hanif, Etrat Noor, Waqas Malik, Shoaib Liaqat
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Salinity is extremely serious problem that has a drastic effect on maize crop, environment and causes economic losses of country. An advance technique to overcome salinity is to develop salt tolerant geno types which require screening of huge germplasm to start a breeding program. Therefore, present study was undertaken to screen out 25 maize hybrids of different origin for salinity tolerance at seedling stage under three levels of salt stress 250 and 300 mM NaCl including one control. The existence of variation for tolerance to enhanced NaCl salinity levels at seedling stage in maize proved that hybrids had differing ability to grow under saline environment and potential variability within specie. Almost all the twenty five maize hybrids behaved varyingly in response to different salinity levels. However, the maize hybrids H6, H13, H21, H23 and H24 expressed better performance under salt stress in terms of all six characters and proved to be as highly tolerant while H22, H17 H20, H18, H4, H9, and H8 were identified as moderately tolerant. Hybrids H14, H5, H11 and H3 H12, H2, were expressed as most sensitive to salinity suggesting that screening is an effective tool to exploit genetic variation among maize hybrids and salt tolerance in maize can be enhanced through selection and breeding procedure.Keywords: salinity, hybrids, maize, variation
Procedia PDF Downloads 7189113 A Method for Rapid Evaluation of Ore Breakage Parameters from Core Images
Authors: A. Nguyen, K. Nguyen, J. Jackson, E. Manlapig
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With the recent advancement in core imaging systems, a large volume of high resolution drill core images can now be collected rapidly. This paper presents a method for rapid prediction of ore-specific breakage parameters from high resolution mineral classified core images. The aim is to allow for a rapid assessment of the variability in ore hardness within a mineral deposit with reduced amount of physical breakage tests. This method sees its application primarily in project evaluation phase, where proper evaluation of the variability in ore hardness of the orebody normally requires prolong and costly metallurgical test work program. Applying this image-based texture analysis method on mineral classified core images, the ores are classified according to their textural characteristics. A small number of physical tests are performed to produce a dataset used for developing the relationship between texture classes and measured ore hardness. The paper also presents a case study in which this method has been applied on core samples from a copper porphyry deposit to predict the ore-specific breakage A*b parameter, obtained from JKRBT tests.Keywords: geometallurgy, hyperspectral drill core imaging, process simulation, texture analysis
Procedia PDF Downloads 3619112 Factors Affecting Air Surface Temperature Variations in the Philippines
Authors: John Christian Lequiron, Gerry Bagtasa, Olivia Cabrera, Leoncio Amadore, Tolentino Moya
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Changes in air surface temperature play an important role in the Philippine’s economy, industry, health, and food production. While increasing global mean temperature in the recent several decades has prompted a number of climate change and variability studies in the Philippines, most studies still focus on rainfall and tropical cyclones. This study aims to investigate the trend and variability of observed air surface temperature and determine its major influencing factor/s in the Philippines. A non-parametric Mann-Kendall trend test was applied to monthly mean temperature of 17 synoptic stations covering 56 years from 1960 to 2015 and a mean change of 0.58 °C or a positive trend of 0.0105 °C/year (p < 0.05) was found. In addition, wavelet decomposition was used to determine the frequency of temperature variability show a 12-month, 30-80-month and more than 120-month cycles. This indicates strong annual variations, interannual variations that coincide with ENSO events, and interdecadal variations that are attributed to PDO and CO2 concentrations. Air surface temperature was also correlated with smoothed sunspot number and galactic cosmic rays, the results show a low to no effect. The influence of ENSO teleconnection on temperature, wind pattern, cloud cover, and outgoing longwave radiation on different ENSO phases had significant effects on regional temperature variability. Particularly, an anomalous anticyclonic (cyclonic) flow east of the Philippines during the peak and decay phase of El Niño (La Niña) events leads to the advection of warm southeasterly (cold northeasterly) air mass over the country. Furthermore, an apparent increasing cloud cover trend is observed over the West Philippine Sea including portions of the Philippines, and this is believed to lessen the effect of the increasing air surface temperature. However, relative humidity was also found to be increasing especially on the central part of the country, which results in a high positive trend of heat index, exacerbating the effects on human discomfort. Finally, an assessment of gridded temperature datasets was done to look at the viability of using three high-resolution datasets in future climate analysis and model calibration and verification. Several error statistics (i.e. Pearson correlation, Bias, MAE, and RMSE) were used for this validation. Results show that gridded temperature datasets generally follows the observed surface temperature change and anomalies. In addition, it is more representative of regional temperature rather than a substitute to station-observed air temperature.Keywords: air surface temperature, carbon dioxide, ENSO, galactic cosmic rays, smoothed sunspot number
Procedia PDF Downloads 3249111 Spatial Temporal Rainfall Trends in Australia
Authors: Bright E. Owusu, Nittaya McNeil
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Rainfall is one of the most essential quantities in meteorology and hydrology. It has important impacts on people’s daily life and excess or inadequate of it could bring tremendous losses in economy and cause fatalities. Population increase around the globe tends to have a corresponding increase in settlement and industrialization. Some countries are affected by flood and drought occasionally due to climate change, which disrupt most of the daily activities. Knowledge of trends in spatial and temporal rainfall variability and their physical explanations would be beneficial in climate change assessment and to determine erosivity. This study describes the spatial-temporal variability of daily rainfall in Australia and their corresponding long-term trend during 1950-2013. The spatial patterns were investigated by using exploratory factor analysis and the long term trend in rainfall time series were determined by linear regression, Mann-Kendall rank statistics and the Sen’s slope test. The exploratory factor analysis explained most of the variations in the data and grouped Australia into eight distinct rainfall regions with different rainfall patterns. Significant increasing trends in annual rainfall were observed in the northern regions of Australia. However, the northeastern part was the wettest of all the eight rainfall regions.Keywords: climate change, explanatory factor analysis, Mann-Kendall and Sen’s slope test, rainfall.
Procedia PDF Downloads 3559110 The Effect of Aerobic Training and Aqueous Extract of C. monogyna (Hawthorn) on Plasma and Heart Angiogenic Mediators in Male Wistar Rats
Authors: Asieh Abbassi Daloii, Ahmad Abdi
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Introduction: Sports information suggests that physical inactivity increases the risk of many diseases, including atherosclerosis. Coronary heart disease, stroke and peripheral vascular disease, atherosclerosis and clinical protests. However, exercise can have beneficial effects on risk factors for atherosclerosis by reducing hyperlipidemia, hypertension, obesity, plaque density, increased insulin sensitivity and glucose tolerance is improved. Despite these findings, there is little information about the molecular mechanisms of interaction between the body and its relation to sport and there arteriosclerosis. The present study aims to investigate the effect of six weeks of progressive aerobic training and aqueous extract of crataegus monogyna on vascular endothelial growth factor (VEGF) variations and angiopoetin-1/2 (ANG- 1/2) in plasma and heart tissue in male Wistar rats. Methods: 30 male Wistar rats, 4-6 months old, were randomly divided into four groups: control crataegus monogyna (N=8), training crataegus monogyna (N=8), control saline (N=6), and training saline (N=8). The aerobic training program included running on treadmill at the speed of 34 meters per minute for 60 minutes per day. The training was conducted for six weeks, five days a week. Following each training session, both experimental and control subjects of crataegus monogyna groups were orally fed with 0.5 mg crataegus monogyna extract per gram of the body weight. The normal saline group was given the same amount of the normal saline solution (NS). Eventually, 72 hours after the last training session, blood samples were taken from inferior Verna cava. Conclusion: It is likely that crataegus monogyna extract compared with aerobic training and even combination of both training and crataegus monogyna extract is more effective on angiogenesis.Keywords: angiopoietin 1, 2, vascular endothelial growth factor, aerobic exercise
Procedia PDF Downloads 3859109 Yield Loss in Maize Due to Stem Borers and Their Integrated Management
Authors: C. P. Mallapur, U. K. Hulihalli, D. N. Kambrekar
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Maize (Zea mays L.) an important cereal crop in the world has diversified uses including human consumption, animal feed, and industrial uses. A major constraint in low productivity of maize in India is undoubtedly insect pests particularly two species of stem borers, Chilo partellus (Swinhoe) and Sesamia inferens (Walker). The stem borers cause varying level of yield losses in different agro-climate regions (25.7 to 80.4%) resulting in a huge economic loss to the farmers. Although these pests are rather difficult to manage, efforts have been made to combat the menace by using effective insecticides. However, efforts have been made in the present study to integrate various possible approaches for sustainable management of these borers. Two field experiments were conducted separately during 2016-17 at Main Agricultural Research Station, University of Agricultural Sciences, Dharwad, Karnataka, India. In the first experiment, six treatments were randomized in RBD. The insect eggs at pinhead stage (@ 40 eggs/plant) were stapled to the under surface of leaves covering 15-20 % of plants in each plot after 15 days of sowing. The second experiment was planned with nine treatments replicated thrice. The border crop with NB -21 grass was planted all around the plots in the specific treatments while, cowpea intercrop (@6:1-row proportion) was sown along with the main crop and later, the insecticidal spray with chlorantraniliprole and nimbecidine was taken upon need basis in the specific treatments. The results indicated that the leaf injury and dead heart incidence were relatively more in the treatments T₂ and T₄ wherein, no insect control measures were made after the insect release (58.30 & 40.0 % leaf injury and 33.42 and 25.74% dead heart). On the contrary, these treatments recorded higher stem tunneling (32.4 and 24.8%) and resulted in lower grain yield (17.49 and 26.79 q/ha) compared to 29.04, 32.68, 40.93 and 46.38 q/ha recorded in T₁, T₃, T₅ and T₆ treatments, respectively. A maximum yield loss of 28.89 percent was noticed in T₂ followed by 19.59 percent in T₄ where no sprays were imposed. The data on integrated management trial revealed the lowest stem borer damage (19.28% leaf injury and 1.21% dead heart) in T₅ (seed treatment with thiamethoxam 70FS @ 8ml/kg seed + cow intercrop along with nimbecidine 0.03EC @ 5.0 ml/l and chlorantraniliprole 18.5SC spray @ 0.2 ml/l). The next best treatment was T₆ (ST+ NB-21 borer with nimbecidine and chlorantraniliprole spray) with 21.3 and 1.99 percent leaf injury and dead heart incidence, respectively. These treatments resulted in highest grain yield (77.71 and 75.53 q/ha in T₅ and T₆, respectively) compared to the standard check, T₁ (ST+ chlorantraniliprole spray) wherein, 27.63 percent leaf injury and 3.68 percent dead heart were noticed with 60.14 q/ha grain yield. The stem borers can cause yield loss up to 25-30 percent in maize which can be well tackled by seed treatment with thiamethoxam 70FS @ 8ml/kg seed and sowing the crop along with cowpea as intercrop (6:1 row proportion) or NB-21 grass as border crop followed by application of nimbecidine 0.03EC @ 5.0 ml/l and chlorantraniliprole 18.5SC @ 0.2 ml/l on need basis.Keywords: Maize stem borers, Chilo partellus, Sesamia inferens, crop loss, integrated management
Procedia PDF Downloads 1819108 Design of Decimation Filter Using Cascade Structure for Sigma Delta ADC
Authors: Misbahuddin Mahammad, P. Chandra Sekhar, Metuku Shyamsunder
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The oversampled output of a sigma-delta modulator is decimated to Nyquist sampling rate by decimation filters. The decimation filters work twofold; they decimate the sampling rate by a factor of OSR (oversampling rate) and they remove the out band quantization noise resulting in an increase in resolution. The speed, area and power consumption of oversampled converter are governed largely by decimation filters in sigma-delta A/D converters. The scope of the work is to design a decimation filter for sigma-delta ADC and simulation using MATLAB. The decimation filter structure is based on cascaded-integrated comb (CIC) filter. A second decimation filter is using CIC for large rate change and cascaded FIR filters, for small rate changes, to improve the frequency response. The proposed structure is even more hardware efficient.Keywords: sigma delta modulator, CIC filter, decimation filter, compensation filter, noise shaping
Procedia PDF Downloads 4629107 Engineering Photodynamic with Radioactive Therapeutic Systems for Sustainable Molecular Polarity: Autopoiesis Systems
Authors: Moustafa Osman Mohammed
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This paper introduces Luhmann’s autopoietic social systems starting with the original concept of autopoiesis by biologists and scientists, including the modification of general systems based on socialized medicine. A specific type of autopoietic system is explained in the three existing groups of the ecological phenomena: interaction, social and medical sciences. This hypothesis model, nevertheless, has a nonlinear interaction with its natural environment ‘interactional cycle’ for the exchange of photon energy with molecular without any changes in topology. The external forces in the systems environment might be concomitant with the natural fluctuations’ influence (e.g. radioactive radiation, electromagnetic waves). The cantilever sensor deploys insights to the future chip processor for prevention of social metabolic systems. Thus, the circuits with resonant electric and optical properties are prototyped on board as an intra–chip inter–chip transmission for producing electromagnetic energy approximately ranges from 1.7 mA at 3.3 V to service the detection in locomotion with the least significant power losses. Nowadays, therapeutic systems are assimilated materials from embryonic stem cells to aggregate multiple functions of the vessels nature de-cellular structure for replenishment. While, the interior actuators deploy base-pair complementarity of nucleotides for the symmetric arrangement in particular bacterial nanonetworks of the sequence cycle creating double-stranded DNA strings. The DNA strands must be sequenced, assembled, and decoded in order to reconstruct the original source reliably. The design of exterior actuators have the ability in sensing different variations in the corresponding patterns regarding beat-to-beat heart rate variability (HRV) for spatial autocorrelation of molecular communication, which consists of human electromagnetic, piezoelectric, electrostatic and electrothermal energy to monitor and transfer the dynamic changes of all the cantilevers simultaneously in real-time workspace with high precision. A prototype-enabled dynamic energy sensor has been investigated in the laboratory for inclusion of nanoscale devices in the architecture with a fuzzy logic control for detection of thermal and electrostatic changes with optoelectronic devices to interpret uncertainty associated with signal interference. Ultimately, the controversial aspect of molecular frictional properties is adjusted to each other and forms its unique spatial structure modules for providing the environment mutual contribution in the investigation of mass temperature changes due to pathogenic archival architecture of clusters.Keywords: autopoiesis, nanoparticles, quantum photonics, portable energy, photonic structure, photodynamic therapeutic system
Procedia PDF Downloads 1269106 Anatomy of the Human Mitral Valve Leaflets: Implications for Transcatheter and Surgical Mitral Valve Repair Techniques
Authors: Agata Krawczyk-Ozog, Mateusz K. Holda, Mateusz Koziej, Danuta Sorysz, Zbigniew Siudak, Wieslawa Klimek-Piotrowska, Dariusz Dudek
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Introduction: Rapid development of the surgical and less-invasive percutaneous mitral valve repair procedures greatly increase the interest of the mitral valve anatomy. The aim of this study was to characterize morphological variability of the mitral valve leaflets and to provide the size of their particular parts. Materials and Methods: In the study, we included 200 autopsied human hearts from Caucasian individuals (25% females) with mean age 47.5 (±17.9) without any valvular diseases. The morphology of the mitral valve was evaluated. The intercommissural and aorto-mural diameters of the mitral annulus were measured. All leaflets and their scallops were identified. The base and the height of the posteromedial commissure (PM-C), anterolateral commissure (AL-C), anterior leaflet (AL) and posterior leaflet (PL) with their scallops were measured. Results: The intercommissural diameter was 28.0±4.8 mm, the aorto-mural diameter 19.7±4.8 mm, circumference of the mitral annulus 89.9±12.6 mm and the area of the mitral valve 485.4±171.4 mm2. Classical mitral valves (AL+AL-C+PL(P1,P2,P3)+PM-C) were found in 141 (70.5%) specimens. In classical type, the mean AL base and height were 30.8±4.9 mm and 20.6±4.2 mm, while mean PL base and height 45.1±8.2 mm 12.9±2.8 mm respectively. The mean ratio of the AL base to PL base was 0.7±0.2. Variations in PL were found in 55 (27.5%) and in AL in 5 (2.5%) hearts. The most common variations were: valve with one accessory scallop (AcS) between P3 and PM-C (7%); AcS between P1 and AL-C (4%); connections of P2 and P3 scallops (4%); connections of P1 and P2 scallops (3%); AcS in AL (2.5%). All AcS were smaller than the main PL scallops. The mean intertrigonal distance was 21.9±3.8 mm. Conclusions: In all cases, the mitral valve is built by two main leaflets with possible variants in secondary to leaflets scallops (29.5%). The variations are largely associated with PL and are mostly related to the presence of AcS. Anatomically the AL is not divided into scallops, and it occupies 34.5% of the mitral annulus circumference. Understanding the anatomy of the mitral valve leaflets helps to planning and performing mitral valve repair procedures.Keywords: accessory scallop, commissure, connected scallops, human heart, mitral leaflets, mitral valve
Procedia PDF Downloads 3899105 Anthropometric Data Variation within Gari-Frying Population
Authors: T. M. Samuel, O. O. Aremu, I. O. Ismaila, L. I. Onu, B. O. Adetifa, S. E. Adegbite, O. O. Olokoshe
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The imperative of anthropometry in designing to fit cannot be overemphasized. Of essence is the variability of measurements among population for which data is collected. In this paper anthropometric data were collected for the design of gari-frying facility such that work system would be designed to fit the gari-frying population in the Southwestern states of Nigeria comprising Lagos, Ogun, Oyo, Osun, Ondo, and Ekiti. Twenty-seven body dimensions were measured among 120 gari-frying processors. Statistical analysis was performed using SPSS package to determine the mean, standard deviation, minimum value, maximum value and percentiles (2nd, 5th, 25th, 50th, 75th, 95th, and 98th) of the different anthropometric parameters. One sample t-test was conducted to determine the variation within the population. The 50th percentiles of some of the anthropometric parameters were compared with those from other populations in literature. The correlation between the worker’s age and the body anthropometry was also investigated.The mean weight, height, shoulder height (sitting), eye height (standing) and eye height (sitting) are 63.37 kg, 1.57 m, 0.55 m, 1.45 m, and 0.67 m respectively.Result also shows a high correlation with other populations and a statistically significant difference in variability of data within the population in all the body dimensions measured. With a mean age of 42.36 years, results shows that age will be a wrong indicator for estimating the anthropometry for the population.Keywords: anthropometry, cassava processing, design to fit, gari-frying, workstation design
Procedia PDF Downloads 2539104 A Comparison of Caesarean Section Indications and Characteristics in 2009 and 2020 in a Saudi Tertiary Hospital
Authors: Sarah K. Basudan, Ragad I. Al Jazzar, Zeinah Sulaihim, Hanan M. Al-Kadri
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Background: Cesarean section has been increasing in recent years, with a wide range of etiologies contributing to this rise. This study aimed to assess the indications, outcomes, and complications in Riyadh, Saudi Arabia. Methods: A Retrospective Cohort study was conducted at King Abdulaziz medical city. The study includes two cohorts: G1 (2009) and G2 (2020) groups who met the inclusion criteria. The data was transferred to the SPSS (statistical package for social sciences) version 24 for analysis. The initial descriptive statistics were run for all variables, including numerical and categorical data. The numerical data were reported as median, and standard deviation and categorical data were reported as frequencies and percentages. Results: The data were collected from 399 women who were divided into two groups, G1(199) and G2(200). The mean age of all participants is 32+-6; G1 and G2 had significant differences in age means with 30+-6 and 34+-5, respectively, with a p-value of <0.001, which indicates delayed fertility by four years. Moreover, a breech presentation was less likely to occur in G2 (OR 0.64, CI: 0.21-0.62. P<0.001). Nonetheless, maternal causes such as repeated C-sections and maternal medical conditions were more likely to happen in G2 (OR 1.5, CI: 1.04-2.38, p=0.03) and (OR 5.4, CI: 1.12-23.9, P=0.01), respectively. Furthermore, postpartum hemorrhage showed an increase of 12% in G2 (OR 5.4, CI: 2.2-13.4, p<0.001). G2 was more likely to be admitted to the neonatal intensive care unit (NICU) (OR 16, CI: 7.4-38.7) and to special care baby (SCB) (OR 7.2, CI: 3.9-13.1), both with a p-value<0.001 compared to regular nursery admission. Conclusion: There are multiple factors that are contributing to the increase in c section rate in a Saudi tertiary hospitals. The factors were suggested to be previous c-sections, abnormal fetal heart rate, malpresentation, and maternal or fetal medical conditions.Keywords: cesarean sections, maternal indications, maternal complications, neonatal condition
Procedia PDF Downloads 919103 Stability Analysis of Green Coffee Export Markets of Ethiopia: Markov-Chain Analysis
Authors: Gabriel Woldu, Maria Sassi
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Coffee performs a pivotal role in Ethiopia's GDP, revenue, employment, domestic demand, and export earnings. Ethiopia's coffee production and exports show high variability in the amount of production and export earnings. Despite being the continent's fifth-largest coffee producer, Ethiopia has not developed its ability to shine as a major exporter in the globe's green coffee exports. Ethiopian coffee exports were not stable and had high volume and earnings fluctuations. The main aim of this study was to analyze the dynamics of the export of coffee variation to different importing nations using a first-order Markov Chain model. 14 years of time-series data has been used to examine the direction and structural change in the export of coffee. A compound annual growth rate (CAGR) was used to determine the annual growth rate in the coffee export quantity, value, and per-unit price over the study period. The major export markets for Ethiopian coffee were Germany, Japan, and the USA, which were more stable, while countries such as France, Italy, Belgium, and Saudi Arabia were less stable and had low retention rates for Ethiopian coffee. The study, therefore, recommends that Ethiopia should again revitalize its market to France, Italy, Belgium, and Saudi Arabia, as these countries are the major coffee-consuming countries in the world to boost its export stake to the global coffee markets in the future. In order to further enhance export stability, the Ethiopian Government and other stakeholders in the coffee sector should have to work on reducing the volatility of coffee output and exports in order to improve production and quality efficiency, so that stabilize markets as well as to make the product attractive and price competitive in the importing countries.Keywords: coffee, CAGR, Markov chain, direction of trade, Ethiopia
Procedia PDF Downloads 1399102 Conscious Intention-based Processes Impact the Neural Activities Prior to Voluntary Action on Reinforcement Learning Schedules
Authors: Xiaosheng Chen, Jingjing Chen, Phil Reed, Dan Zhang
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Conscious intention can be a promising point cut to grasp consciousness and orient voluntary action. The current study adopted a random ratio (RR), yoked random interval (RI) reinforcement learning schedule instead of the previous highly repeatable and single decision point paradigms, aimed to induce voluntary action with the conscious intention that evolves from the interaction between short-range-intention and long-range-intention. Readiness potential (RP) -like-EEG amplitude and inter-trial-EEG variability decreased significantly prior to voluntary action compared to cued action for inter-trial-EEG variability, mainly featured during the earlier stage of neural activities. Notably, (RP) -like-EEG amplitudes decreased significantly prior to higher RI-reward rates responses in which participants formed a higher plane of conscious intention. The present study suggests the possible contribution of conscious intention-based processes to the neural activities from the earlier stage prior to voluntary action on reinforcement leanring schedule.Keywords: Reinforcement leaning schedule, voluntary action, EEG, conscious intention, readiness potential
Procedia PDF Downloads 799101 Sudden Death of a Cocaine Body Packer: An Autopsy Examination Findings
Authors: Parthasarathi Pramanik
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Body packing is a way of transfer drugs across the international border or any drug prohibited area. The drugs are usually hidden in body packets inside the anatomical body cavities like mouth, intestines, rectum, ear, vagina etc. Cocaine is a very common drug for body packing across the world. A 48 year old male was reported dead in his hotel after complaining of chest pain and vomiting. At autopsy, there were eighty-two white cylindrical body packs in the stomach, small and large intestines. Seals of few of the packets were opened. Toxicological examination revealed presence of cocaine in the stomach, liver, kidney and hair samples. Microscopically, presence of myocardial necrosis with interstitial oedema along with hypertrophy and fibrosis of the myocardial fibre suggested heart failure due to cocaine cardio toxicity. However, focal lymphocyte infiltration and perivascular fibrosis in the myocardium also indicated chronic cocaine toxicity of the deceased. After careful autopsy examination it was considered the victim was died due congestive heart failure secondary to acute and chronic cocaine poisoning.Keywords: cardiac failure, cocaine, body packer, sudden death
Procedia PDF Downloads 3209100 Tissue-Specific Distribution of Cytochrome P450 1A1 and 3A in Rainbow Trout (Oncorhynchus mykiss)
Authors: Viktoriia Burkina, Vladimir Zlabek, Galia Zamaratskaia
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Cytochromes P450 (CYP) are important family of enzymes in Phase I metabolism. Environmental pollutants often act as inducers of the gene expression and activities CYP1A1 and CYP3A-like isoforms in fish. The activities are generally measured in the fish liver or gills, and less is known about tissue distribution of expression. In present study, the CYP1A1 and CYP3A-like activities were measured in rainbow trout liver, gill, intestine, heart, brain and gonads. The activities of CYP1A1 and CYP3A-like proteins were estimated as the rates of 7-ethoxyresorufin-O-deethylation (EROD) and benzyloxy-4-trifluoromethylcoumarin-O-debenzyloxylation (BFCOD), respectively. The CYP1A1 and CYP3A-like activities were detectable in all investigated fish tissues, with the highest activity in hepatic tissue followed by heart > brain > gill > intestine > gonads. To confirm the presence of CYP1A1 in different tissues, EROD activity was measured in presence of the selective inhibitors ellipticine (CYP1A1), ketoconazole (CYP3A), 8-methoxypsoralen (human CYP2A) and diallyl sulphide (CYP2E1). It was found that ellipticine, ketoconazole and 8-methoxypsoralen inhibited hepatic EROD activity by 88-98%. Ellipticine inhibited gill, intestine, and gonad EROD activity by 50%. In conclusion, EROD and BFCOD activities were detected in rainbow trout liver, gill, intestine, heart, brain and gonads. Further studies are needed to fully identify all CYP450 isoforms responsible for these activities. Acknowledgement: The study was financially supported by the Ministry of Education, Youth and Sports of the Czech Republic - projects „CENAKVA “(No. CZ.1.05/2.1.00/01.0024), “CENAKVA Center Development “(No. CZ.1.05/2.1.00/19.0380), “CENAKVA II “(No. LO1205 under the NPU I program), and "Development of USB - International mobility (No. CZ.02.2.69/0.0/0.0/16_027/0008364).Keywords: BFCOD, EROD, fish, phase I metabolism, selective inhibitors
Procedia PDF Downloads 1519099 Pharmacogenetic Analysis of Inter-Ethnic Variability in the Uptake Transporter SLCO1B1 Gene in Colombian, Mozambican, and Portuguese Populations
Authors: Mulata Haile Nega, Derebew Fikadu Berhe, Vera Ribeiro Marques
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There is no epidemiologic data on this gene polymorphism in several countries. Therefore, this study aimed to assess the genotype and allele frequencies of the gene variant in three countries. This study involved healthy individuals from Colombia, Mozambique, and Portugal. Genomic DNA was isolated from blood samples using the Qiamp DNA Extraction Kit (Qiagen). The isolated DNA was genotyped using Polymerase Chain Reaction (PCR) - Restriction Fragment Length Polymorphism. Microstat and GraphPad quick cal software were used for the Chi-square test and evaluation of Hardy-Weinberg equilibrium, respectively. A total of 181 individuals’ blood sample was analyzed. Overall, TT (74.0%) genotype was the highest, and CC (7.8%) was the lowest. Country wise genotypic frequencies were Colombia 47(70.2%) TT, 12(17.9%) TC and 8(11.9%) CC; Mozambique 47(88.7%) TT, 5(9.4%) TC, and 1(1.9%) CC; and Portugal 40(65.6%) TT, 16(26.2%) TC, and 5(8.2%) CC. The reference (T) allele was highest among Mozambicans (93.4%) compared to Colombians (79.1%) and Portuguese (78.7%). Mozambicans showed statistically significant genotypic and allelic frequency differences compared to Colombians (p<0.01) and Portuguese (p <0.01). Overall and country-wise, the CC genotype was less frequent and relatively high for Colombians and Portuguese populations. This finding may imply statins risk-benefit variability associated with CC genotype among these populations that needs further understanding.Keywords: c.521T>C, polymorphism, SLCO1B1, SNP, statins
Procedia PDF Downloads 1359098 Finite Difference Based Probabilistic Analysis to Evaluate the Impact of Correlation Length on Long-Term Settlement of Soft Soils
Authors: Mehrnaz Alibeikloo, Hadi Khabbaz, Behzad Fatahi
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Probabilistic analysis has become one of the most popular methods to quantify and manage geotechnical risks due to the spatial variability of soil input parameters. The correlation length is one of the key factors of quantifying spatial variability of soil parameters which is defined as a distance within which the random variables are correlated strongly. This paper aims to assess the impact of correlation length on the long-term settlement of soft soils improved with preloading. The concept of 'worst-case' spatial correlation length was evaluated by determining the probability of failure of a real case study of Vasby test fill. For this purpose, a finite difference code was developed based on axisymmetric consolidation equations incorporating the non-linear elastic visco-plastic model and the Karhunen-Loeve expansion method. The results show that correlation length has a significant impact on the post-construction settlement of soft soils in a way that by increasing correlation length, probability of failure increases and the approach to asymptote.Keywords: Karhunen-Loeve expansion, probability of failure, soft soil settlement, 'worst case' spatial correlation length
Procedia PDF Downloads 168