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Authors: Ndou Rembuluwani Moddy, Daniel Ter Goon, Takalani Grace Tshitangano, Lindelani Fhumudzani Mushaphi

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Obesity is a global public health problem. The study aimed to determine the risk factors associated with and the consequences of obesity among residents of Tshikota, Makhado Municipality, Limpopo Province, South Africa. A cross-sectional study involving 318 randomly selected adults aged 18-45 years residing at Tshikota, Makhado Local Municipality, South Africa. Sociodemographic information includes age, gender, educational level, occupation, behavioral lifestyle, environmental, psychological, and family history. Anthropometric, blood pressure, and blood glucose measurements followed standard procedure. The prevalence of obesity and overweight was 35.5% and 28.6%, respectively. About 75.2% of obese do not engage in physical activity. Most participants (63.5%) take meals three times a day, and 19.2% do not skip breakfast. Most participants do not have access to fruits and vegetables. Participants who were pre-hypertensive were 92(28.9%) and 32(10.1%) were in Stage 1 hypertension. Of the participants with Class 1 obesity, 40.9% were pre-hypertensive, and 15.2% were in Stage 1 hypertension. In Class 2 obesity, 37.8% were pre-hypertensive, and 26.7% were in Stage 1 hypertension. There was a significant difference between BMI and blood pressure among participants (p=0.00). About 6.1% of the participants in Class 1 obesity were at high risk, and 3.0% were at very high risk of glucose levels. Regarding cholesterol levels, 65 (20.4%) were at borderline, and 17(5.3%) were at high risk. There was no significant difference in BMI and cholesterol levels among participants (p= 0.20). The prevalence of obesity and overweight was high among residents of this setting. Age, marital and educational status, and employment were significantly associated with obesity. An obesity awareness campaign is crucial, and the availability of supermarkets and full-service grocery stores would provide accessibility to healthy food such as fruits and vegetables.

Keywords: obesity, overweight, risk factors, adults.

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Authors: Rui Miguel Costa, Jose Pestana, David Costa, Paula Mangia, Catarina Correia, Mafalda Pinto Coelho

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There is lack of studies examining the relation of different heart rate variability (HRV) parameters with the risk of erectile dysfunction (ED) in younger men. Thus, the present study aimed at examining, in a nonclinical sample of men aged 19-39 years old (mean age = 23.98 years, SD = 4.90), the relations of risk of ED with the standard deviation of the heart rate (SD of HR), high and low frequency power of HRV, and low-to-high frequency HRV ratio. Eighty-three heterosexual Portuguese men completed the 5-item version of the International Index of Erectile Function (IIEF-5) and HRV parameters were calculated from a 5-minute resting period. Risk of ED was determined by IIEF-5 scores of 21 or less. Fifteen men (18.1%) reported symptoms of ED (14 with mild and one with mild to moderate symptoms). Univariate analyses of variance revealed that risk of ED was related to lesser SD of HR and lesser low-frequency power, the two HRV parameters that express a coupling of higher vagal and sympathetic tone. Risk of ED was unrelated to high-frequency power and low-to-high frequency HRV ratio. Further, in a logistic regression, the risk of ED was independently predicted by older age and lower SD of HR, but not by low-frequency power, having a regular sexual partner, and cohabiting. The results provide preliminary evidence that, in younger men, a coupling of higher vagal and sympathetic tone, as indexed by the SD of HR, is important for erections. Greater resting SD of HR might reflect better vascular and interpersonal function via vagal tone coupled with greater motor mobilization to pursue sexual intercourse via sympathetic tone. Many interventions can elevate HRV; future research is warranted on how they can be tailored to treat ED in younger men.

Keywords: erectile dysfunction, heart rate variability, standard deviation of the heart rate, younger men

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Authors: Bharat Kumar, Deepak Kumar, Vijay Chaudhry

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Zirconium alloys exhibit low neutron absorption cross-section and excellent mechanical properties. Due to these unique characteristics, these materials are widely used in designing core components of pressurized heavy water reactors (PHWRs). Another material that is widely used in the design of reactor core is stainless steel. Under operating conditions of the reactor, there are possibilities for mechanical and tribological interaction between the components made of zirconium alloy (Zr-2.5 Nb) and stainless steel (SS-410). This may result in wear of the material. To study the tribological characteristics of Zr-2.5 Nb and SS-410, low amplitude reciprocating wear tests are conducted at room temperature and at high temperatures (260 degrees Celsius). The tests are conducted at frequencies ranging from 5 Hz to 25 Hz. The displacement amplitude is varied from 200 µm to 600 µm. The responses are recorded, analyzed and correlated with damage observed using scanning electron microscopy (SEM) and an optical profilometer. Energy dispersive spectroscopy (EDS) is used to study the damage mechanism prevailing at the contact interface. A higher coefficient of friction (COF) is observed at higher temperatures as compared to the one at room temperature. Tests carried out at high temperature reveals adhesive wear as the dominant mechanism resulting in significant material transfer.

Keywords: PHWRs, Zr-2.5Nb, SS-410, wear

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Authors: Wen Po Cheng, Chia Yun Chung, Ruey Fang Yu, Chao Feng Chen

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The main objective of this research was to study the differences of aluminum hydrolytic products between two PACl preparation methods. These two methods were the acidification process of freshly formed amorphous Al(OH)₃ and the conventional alkalization process of aluminum chloride solution. According to Ferron test and ²⁷Al NMR analysis of those two PACl preparation procedures, the reaction rate constant (k) values and Al₁₃ percentage of acid addition process at high basicity value were both lower than those values of the alkaline addition process. The results showed that the molecular structure and size distribution of the aluminum species in both preparing methods were suspected to be significantly different at high basicity value.

Keywords: polyaluminum chloride, Al13, amorphous aluminum hydroxide, Ferron test

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Authors: Faizan Ali, Dayu Zhou, Xiaohua Liu, Tony Schenk, Johannes Muller, Uwe Schroeder

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Recently, the ferroelectricity (FE) and anti-ferroelectricity (AFE) introduced in so-called 'high-k dielectric' HfO₂ material incorporated with various dopants (Si, Gd, Y, Sr, Gd, Al, and La, etc.), HfO₂-ZrO₂ solid-solution, Al or Si-doped Hf₀.₅Zr₀.₅O₂ and even undoped HfO₂ thin films. The origin of FE property was attributed to the formation of a non-centrosymmetric orthorhombic (o) phase of space group Pbc2₁. To the author’s best knowledge, AFE property was observed only in HfO₂ doped with a certain amount of Si, Al, HfₓZr₁₋ₓO₂ (0 ≤ x < 0.5), and in Si or Al-doped Hf₀.₅Zr₀.₅O₂. The origin of the anti-ferroelectric behavior is an electric field induced phase transition between the non-polar tetragonal (t) and the polar ferroelectric orthorhombic (o) phase. Compared with the significant amount of studies for the FE properties in the context of non-volatile memories, AFE properties of HfO₂-based and HfₓZr₁₋ₓO₂ (HZO) thin films have just received attention recently for energy-related applications such as electrocaloric cooling, pyroelectric energy harvesting, and electrostatic energy storage. In this work, energy storage and solid state cooling properties of Si-doped HfO₂ AFE thin films are investigated. Owing to the high field-induced polarization and slim double hysteresis, an extremely large Energy storage density (ESD) value of 61.2 J cm⁻³ is achieved at 4.5 MV cm⁻¹ with high efficiency of ~65%. In addition, the ESD and efficiency exhibit robust thermal stability in 210-400 K temperature range and excellent endurance up to 10⁹ times of charge/discharge cycling at a very high electric field of 4.0 MV cm⁻¹. Similarly, for solid-state cooling, the maximum adiabatic temperature change (

Keywords: thin films, energy storage, endurance, solid state cooling, anti-ferroelectric

Procedia PDF Downloads 126

Authors: Vahab Behmanesh

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Metabolic syndrome is defined as having at least three of the five metabolic risk factors, including abdominal obesity, high blood pressure, high triglycerides, low HDL, and insulin resistance. Lifestyle changes towards reducing physical activity, unhealthy eating habits Especially the high-fat and high-carbohydrate diet is directly related to metabolic syndrome, and due to the epidemic of overweight and sedentary life, metabolic syndrome is a serious problem worldwide. On the other hand, vitamin D deficiency is considered as one of the most common problems in the world, which is related to the dysfunction of beta cells and insulin resistance, and therefore, vitamin D deficiency is considered as a factor in the occurrence of metabolic syndrome. 40 subjects (age: 16.12 ± 4.4 years and body mass index 25.61 ± 4.4 kg/m2) were randomly assigned to groups of aerobic exercise and placebo, aerobic exercise and vitamin D and placebo (no exercise) were divided. Vitamin D was taken at a dose of 50,000 units per week in a double-blind format for eight weeks, and the daily aerobic exercise program was performed for 50 to 60 minutes, three doses per week, with an intensity of 50-60% of the maximum heart rate. From one-way analysis of variance, Factorial variance analysis (2x2) repeated measurement and correlated t-test were used for data analysis. Aerobic exercise and vitamin D intake reduced all metabolic risk indicators and blood insulin (P < 0.05). However, the subjective feeling of hunger did not change significantly (P < 0.05). Regarding waist circumference and blood glucose, the effect of exercise combined with vitamin D consumption was greater than the corresponding effect in the vitamin D group (P < 0.05). Aerobic exercises and vitamin D intake are safe and effective for improving cardiometabolic health, Imam adds vitamin D to the exercise program has more benefits for weight and blood sugar control, which suggests prescribing it for patients with metabolic syndrome.

Keywords: vitamin D, aerobic exercise, metabolic control, adolescents

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Authors: Muhammad Saeed, Sheeba Khalid

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Aqueous pollution due to the textile industry is an important issue. Photocatalysis using metal oxides as catalysts is one of the methods used for eradication of dyes from textile industrial effluents. In this study, the synthesis, characterization, and evaluation of photocatalytic activity of Ag-TiO₂ are reported. TiO₂ catalysts with 2, 4, 6 and 8% loading of Ag were prepared by green methods using Azadrachea indica leaves' extract as reducing agent and titanium dioxide and silver nitrate as precursor materials. The 4% Ag-TiO₂ exhibited the best catalytic activity for degradation of dyes. Prepared catalyst was characterized by advanced techniques. Catalytic degradation of methylene blue and rhodamine B were carried out in Pyrex glass batch reactor. Deposition of Ag greatly enhanced the catalytic efficiency of TiO₂ towards degradation of dyes. Irradiation of catalyst excites electrons from conduction band of catalyst to valence band yielding an electron-hole pair. These photoexcited electrons and positive hole undergo secondary reaction and produce OH radicals. These active radicals take part in the degradation of dyes. More than 90% of dyes were degraded in 120 minutes. It was found that there was no loss catalytic efficiency of prepared Ag-TiO₂ after recycling it for two times. Photocatalytic degradation of methylene blue and rhodamine B followed Eley-Rideal mechanism which states that dye reacts in fluid phase with adsorbed oxygen. 27 kJ/mol and 20 kJ/mol were found as activation energy for photodegradation of methylene blue and rhodamine B dye respectively.

Keywords: TiO₂, Ag-TiO₂, methylene blue, Rhodamine B., photo degradation

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Authors: Ernesto A. Lagarda-Leyva, Manuel A. Valenzuela L., José G. Oshima C., Arnulfo A. Naranjo-Flores

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From August to December of 2016, a diagnostic and strategic planning study was carried out on the supply chain of the company Agropecuaria GABO S.A. de C.V. The final product of the study was the development of the strategic plan and a project portfolio to meet the demands of the three links in the supply chain of the Roma tomato exported annually to the United States of America. In this project, the strategic objective of ensuring the proper handling of the product was selected and one of the goals associated with this was the employment of quantitative methods to support decision making. Considering the antecedents, the objective of this case study was to develop a model to analyze the behavioral dynamics in the distribution chain, from the logistics of storage and shipment of Roma tomato in 81-case pallets (11.5 kg per case), to the two pre-cooling rooms and eventual loading onto transports, seeking to reduce the bottleneck and the associated costs by means of a dynamic interface. The methodology used was that of system dynamics, considering four phases that were adapted to the purpose of the study: 1) the conceptualization phase; 2) the formulation phase; 3) the evaluation phase; and 4) the communication phase. The main practical conclusions lead to the possibility of reducing both the bottlenecks in the cooling rooms and the costs by simulating scenarios and modifying certain policies. Furthermore, the creation of the dynamic interface between the model and the stakeholders was achieved by generating interaction with buttons and simple instructions that allow making modifications and observing diverse behaviors.

Keywords: agrilogistics, distribution, scenarios, system dynamics

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Authors: Asmaa Zaraq

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In the present work we report X-ray powder diffraction measurements of SrCaCoTeO6 and SrCaNiTeO6, at different temperatures. The crystal structures at room temperature of both compounds are determined; and results showing the existence of high-temperature phase transitions in them are presented. Both compounds have double perovskite structure with 1:1 ordered arrangement of the B site cations. At room temperature their symmetries are described with the P21/n space group, that correspond to the (a+b-b-) tilt system. The evolution with temperature of the structure of both compounds shows the presence of three phase transitions: a continuous one, at 450 and 500 K, a discontinuous one, at 700 and 775 K, and a continuous one at 900 and 950 K for SrCaCoTeO6 and SrCaNiTeO6, respectively with the following phase-transition sequence: P21/n → I2/m → I4/m → Fm-3m.

Keywords: double perovskites, caracterisation DRX, transition de phase

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Authors: Ahmed Torad

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Background: Knee osteoarthritis (OA) is a prevalent musculoskeletal condition characterized by pain and functional impairment. While various rehabilitation approaches have been employed, the effectiveness of high-intensity interval training (HIIT) compared to traditional rehabilitation exercises remains unclear. Objective: This randomized controlled trial aimed to compare the effects of HIIT and traditional rehabilitation exercises on pain reduction, functional improvement, and quality of life in individuals with knee OA. Methods: A total of 120 participants diagnosed with knee OA were randomly allocated into two groups: the HIIT group (n=60) and the traditional rehabilitation group (n=60). The HIIT group participated in a 12-week supervised program consisting of high-intensity interval exercises, while the traditional rehabilitation group followed a conventional physiotherapy regimen. Outcome measures included visual analog scale (VAS) pain scores, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and the Short Form-36 Health Survey (SF-36) at baseline and after the intervention period. Results: Both groups showed significant improvements in pain scores, functional outcomes (WOMAC), and quality of life (SF-36) after 12 weeks of intervention. However, the HIIT group demonstrated superior pain reduction (p<0.001), functional improvement (p<0.001), and physical health-related quality of life (p=0.002) compared to the traditional rehabilitation group. No significant differences were observed in mental health-related quality of life between the two groups. Conclusion: High-intensity interval training appears to be a more effective rehabilitation approach than traditional exercises for individuals with knee osteoarthritis, resulting in greater pain reduction, improved function, and enhanced physical health-related quality of life. These findings suggest that HIIT may represent a promising intervention strategy for managing knee OA and enhancing the overall well-being of affected individuals.

Keywords: knee osteoarthritis, high-intensity interval training, traditional rehabilitation exercises, randomized controlled trial, pain reduction, functional improvement, quality of life

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Authors: O. G. Onuk, L. S. Taura, C. M. Eze, S. M. Ngaram

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The decay chain of radioactive elements in the laboratory and the verification of natural radioactivity of the human body was investigated using the High Purity Germanium (HPGe) detector. Properties of the HPGe detectors were also investigated. The efficiency and energy resolution of HPGe detector used in the laboratory was found to be excellent. The detector was calibrated three times so as to cover a wider energy range. Also the Centroid C of the detector was found to have a linear relationship with the energies of the known gamma-rays. Using the three calibrations of the detector, the energy of an unknown radionuclide was found to follow the decay chain of thorium-232 (232Th) and it was also found that an average adult has about 2.5g Potasium-40 (40K) in the body.

Keywords: detector, efficiency, energy, radionuclides, resolution

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Authors: Jayesh M. Sonawane, Prakash C. Ghosh

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Landfill leachate emerges as a promising feedstock for microbial fuel cells (MFCs). In the present investigation, direct air-breathing cathode-based MFCs are fabricated to investigate the potential of landfill leachate. Three MFCs that have different cathode areas are fabricated and investigated for 17 days under open circuit conditions. The maximum open circuit voltage (OCV) is observed to be as high as 1.29 V. The maximum cathode area specific power density achieved in the reactor is 1513 mW m^-2. Further studies are under progress to understand the origin of high OCV obtained from landfill leachate-based MFCs.

Keywords: microbial fuel cells, landfill leachate, air-breathing cathode, performance study

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Authors: G. H. Li, M. Liu, H. J. Qi, Q. Zhu, W. Z. He

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The drilling and riveting processes are widely used in the assembly of carrier rocket, which makes the efficiency and quality of drilling become the important factor affecting the assembly process. According to the problem existing in the drilling of thick stacked plate (thickness larger than 10mm) of carrier rocket, such as drill break, large noise and burr etc., experimental study of the influence of tool material on the drilling was carried out. The cutting force was measured by a piezoelectric dynamometer, the aperture was measured with an outline projector, and the burr is observed and measured by a digital stereo microscope. Through the measurement, the effects of tool material on the drilling were analyzed from the aspects of drilling force, diameter, and burr. The results show that, compared with carbide drill and coated carbide one, the drilling force of high speed steel is larger. But, the application of high speed steel also has some advantages, e.g. a higher number of hole can be obtained, the height of burr is small, the exit is smooth and the slim burr is less, and the tool experiences wear but not fracture. Therefore, the high speed steel tool is suitable for the drilling of thick stacked plate of 2219 Aluminum alloy.

Keywords: 2219 aluminum alloy, thick stacked plate, drilling, tool material

Procedia PDF Downloads 233

Authors: Tawanda Mushiri, Charles Mbohwa

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When an external load is applied to one of its ends, a pipe’s bends cross section tends to deform significantly both in and out of its end plane. This shell type behaviour characteristic of pipe bends and mainly due to their curves geometry accounts for their greater flexibility. This added flexibility is also accompanied by stressed and strains that are much higher than those present in a straight pipe. The primary goal of this research is to study the elastic-plastic behaviour of pipe bends under out of plane moment loading. It is also required to study the effects of changing the value of the pipe bend factor and the value of the internal pressure on that behaviour and to determine the value of the limit moments in each case. The results of these analyses are presented in the form of load deflection plots for each load case belonging to each model. From the load deflection curves, the limit moments of each case are obtained. The limit loads are then compared to those computed using some of the analytical and empirical equation available in the literature. The effects of modelling parameters are also studied. The results obtained from small displacement and large displacement analyses are compared and the effects of using a strain hardened material model are also investigated. To better understand the behaviour of pipe elbows under out of plane bending and internal pressure, it was deemed important to know how the cross section deforms and to study the distribution of stresses that cause it to deform in a particular manner. An elbow with pipe bend factor h=0.1 to h=1 is considered and the results of the detailed analysis are thereof examined.

Keywords: elasto-plastic, finite element analysis, pipe bends, simulation

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Authors: Eun-Chan Kim, Jeong-Hwan Oh, Seung-Guk Lee

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Billions of tones of ballast water including various aquatic organisms are being carried around the world by ships. When the ballast water is discharged into new environments, some aquatic organisms discharged with ballast water may become invasive and severely disrupt the native ecology. Thus, International Maritime Organization (IMO) adopted the Ballast Water Management Convention in 2004. Regulation A-4 of the convention states that a government in waters under their jurisdiction may grant exemptions to any requirements to ballast water management, but only when they are granted to a ship or ships on a voyage or voyages between specified ports or locations, or to a ship which operates exclusively between specified ports or locations. In order to grant exemptions, risk assessment should be conducted based on the guidelines for risk assessment developed by the IMO. For the risk assessment, it is essential to collect the relevant information and establish a database system. This paper studies the database system for ballast water risk assessment. This database consists of the shipping database, ballast water database, port environment database and species database. The shipping database has been established based on the data collected from the port management information system of Korea Government. For the ballast water database, ballast water discharge has only been estimated by the loading/unloading of the cargoes as the convention has not come into effect yet. The port environment database and species database are being established based on the reference documents, and existing and newly collected monitoring data. This database system has been approved to be a useful system, capable of appropriately analyzing the risk assessment in the all ports of Korea.

Keywords: ballast water, IMO, risk assessment, shipping, environment, species

Procedia PDF Downloads 517

Authors: Aung Aung Kyi, Khin Khin Aye

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The mode of teaching and learning has been changed dramatically due to the Covid-19 pandemic that made schools close and students may have been away from the campus. However, many schools all over the countries are helping students to facilitate e-learning through online teaching and learning platform. Regarding this, Sarasas bilingual school in Bangkok conducted the high school students’ satisfaction survey since it is important for every school to improve its quality of education that must meet the students' need. For the good of the school's reputation, the purpose of the study is to examine the level of satisfaction that enhances the best services in the future. This study applied random sampling techniques and the data were collected using a self-administered survey. Descriptive analysis and independent sample t-tests were used to measure the importance of satisfaction components. The results showed G-11 (A) students were extremely satisfied with “Accessibility of course resources and materials through online platform” and “Ontime homework submission” while G-11 (B) students were extremely satisfied with “Teacher assisted with guiding my learning activities” and “Course teacher for this online course interacted with me in a timely fashion”. Additionally, they were also satisfied with a clear understanding of the teacher’s introduction during online learning. A significant difference in the satisfaction was observed between G-11 (A) and G-11 (B) students in terms of “A clear understanding on introduction was given by the teacher at the beginning of this online course”(P=0.03), “Teacher assisted with guiding my learning activities” (P=0.003), and “Comfortable surrounding during online learning” (P=0.02). With regard to gender, it has been seen that female high school students were extremely satisfied with the amount of course interaction with their teacher and her guidance with learning activities during online learning. By understanding the survey assessment, schools can improve their quality of education through the best digital educational platform that helps satisfy their students in the future.

Keywords: Bangkok high school students., covid-19 pandemic, online learning platform, satisfaction

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Authors: B. Sudarsan Baskar, S. Pooja Pragati, S. Raj Kumar

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The cost effectiveness in aircraft maintenance is of high privilege in the recent days. The cost effectiveness can be effectively made when line maintenance activities are incorporated at airports during Turn around time (TAT). The present work outcomes the shortcomings that affect the dispatching of the aircrafts, aiming at high fleet operability and low maintenance cost. The operational and cost constraints have been discussed and a suggestive alternative mechanism is proposed. The possible allocation of all deferred maintenance tasks to a set of all deferred maintenance tasks to a set of suitable airport resources have termed as alternative and is discussed in this paper from the data’s collected from the kingfisher airlines.

Keywords: decision support system, aircraft maintenance planning, maintenance-cost, RUL(remaining useful life), logistics, supply chain management

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Authors: Boukrida Rafiq

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Democracy is based on the notion that all citizens have the right to participate in the managing of political affairs and that every citizens input is of equal importance. This basic assumption clearly places emphasis on public participation in maintaining a stable democracy. The level of public participation, however is highly contested with many theorists arguing that too much public participation would overwhelm and ultimately cripple democratic systems. On the other hand, others who favor high levels of participation argue that more citizen involvement leads to greater representation. Regardless of these disagreements over the utopian level of participation, there is widespread agreement amongst scholars that, at the very least, some participation is necessary to maintain democratic systems. The ways in which citizens participate vary greatly and depending on the method used, influence political decision making at varying levels. The method of political participation is a key in controlling public influence over political affairs and therefore is also an integral part of maintaining democracy, whether it be "thin" (low levels of participation) or "Robust" (high levels of participation). High levels of participation or "robust" democracy are argued by some theorists to enhance democracy through providing the opportunity for more issues to be represented during decision making. The notion of widespread participation was first advanced by classical theorists.

Keywords: assumption clearly places emphasis, ultimately cripple, influence political decision making at varying, classical theorists

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Authors: Voodi Kalandhar, Veera Reddy, Yuva Tejasree

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Researchers have become interested in multilevel inverters (MLI) because of their potential for medium- and high-power applications. MLIs are becoming more popular as a result of their ability to generate higher voltage levels, minimal power losses, small size, and low price. These inverters used in high voltage and high-power applications because the stress on the switch is low. Even though many traditional topologies, such as the cascaded H-bridge MLI, the flying capacitor MLI, and the diode clamped MLI, exist, they all have some drawbacks. A complicated control system is needed for the flying capacitor MLI to balance the voltage across the capacitor and diode clamped MLI requires more no of diodes when no of levels increases. Even though the cascaded H-Bridge MLI is popular in terms of modularity and simple control, it requires more no of isolated DC source. Therefore, a topology with fewer devices has always been necessary for greater efficiency and reliability. A new single-phase MLI topology has been introduced to minimize the required switch count in the circuit and increase output levels. With 3 dc voltage sources, 8 switches, and 13 levels at the output, this new single- phase MLI topology was developed. To demonstrate the proposed converter's superiority over the other MLI topologies currently in use, a thorough analysis of the proposed topology will be conducted.

Keywords: DC-AC converter, multi-level inverter (MLI), diodes, H-bridge inverter, switches

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Authors: A. Abdi, A. Barari, A. Hojatollah Nikbakht, Khosro Ebrahim

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Aim: The purpose of the current study was to investigate the effect of a high intensity treadmill running training (8 weeks) with or without aqueous extraction of Crataegus pentagyna on heart and plasma LDH and CK. Design: Thirty-two Wistar male rats (4-6 weeks old, 125-135 gr weight) were used. Animals were randomly assigned into training (n = 16) and control (n = 16) groups and further divided into saline-control (SC, n = 8), saline-training (ST, n = 8), red Crataegus pentagyna extraction -control (CPEC, n = 8), and red Crataegus pentagyna extraction -training (CPET, n = 8) groups. Training groups have performed a high-intensity running program 34 m/min on 0% grade, 60 min/day, 5 days/week) on a motor-driven treadmill for 8 weeks. Animals were fed orally with Crataegus extraction and saline solution (500mg/kg body weight/or 10ml/kg body weight) for last six weeks. Seventy- two hours after the last training session, rats were sacrificed; plasma and heart were excised and immediately frozen in liquid nitrogen. LDH and CK levels were measured by colorimetric method. Statistical analysis was performed using a one way analysis of variance and Tukey test. Significance was accepted at P = 0.05. Results: Result showed that consumption crataegus lowers LDH and CK in heart and plasma. Also the heart LDH and CK were lower in the CPET compared to the ST, while plasma LDH and CK in CPET was higher than the ST. The results of ANOVA showed that the due high-intensity exercise and consumption crataegus, there are significant differences between levels of hearth LDH (P < 0/001), plasma (P < 0/006) and hearth (P < 0/001) CK. Conclusion: It appears that high-intensity exercise led to increased tissue damage and inflammatory factors in plasma. In other hand, consumption aqueous extraction of Red Crataegus maybe inhibits these factors and prevents muscle and heart damage.

Keywords: LDH, CK, crataegus, intensity

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Authors: Mohamed A. Hammad, Dzul Azri Mohamed Noor, Syed Azhar Syed Sulaiman, Ahmed A. Khamis, Abeer Kharshid, Nor Azizah Aziz

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The effect of statins dose intensity (SDI) on glycemic control in patients with existing diabetes is unclear. Also, there are many contradictory findings were reported in the literature; thus, it is limiting the possibility to draw conclusions. This project was designed to compare the effect of SDI on glycated hemoglobin (HbA1c%) control in outpatients with Type 2 diabetes in the endocrine clinic at Hospital Pulau Pinang, Malaysia, between July 2015 and August 2016. A prospective cohort study was conducted, where records of 345 patients with Type 2 diabetes (Moderate-SDI group 289 patients and high-SDI cohort 56 patients) were reviewed to identify demographics and laboratory tests. The target of glycemic control (HbA1c < 7% for patient < 65 years, and < 8% for patient ≥ 65 years) was estimated, and the results were presented as descriptive statistics. From 289 moderate-SDI cohorts with a mean age of 57.3 ± 12.4 years, only 86 (29.8%) cases were shown to have controlled glycemia, while there were 203 (70.2%) cases with uncontrolled glycemia with confidence interval (CI) of 95% (6.2–10.8). On the other hand, the high-SDI group of 56 patients with Type 2 diabetes with a mean age 57.7±12.4 years is distributed among 11 (19.6%) patients with controlled diabetes, and 45 (80.4%) of them had uncontrolled glycemia, CI: 95% (7.1–11.9). The study has demonstrated that the relative risk (RR) of uncontrolled glycemia in patients with Type 2 diabetes that used high-SDI is 1.15, and the excessive relative risk (ERR) is 15%. The absolute risk (AR) is 10.2%, and the number needed to harm (NNH) is 10. Outpatients with Type 2 diabetes who use high-SDI of statin have a higher risk of uncontrolled glycemia than outpatients who had been treated with a moderate-SDI.

Keywords: cohort study, diabetes control, dose intensity, HbA1c, Malaysia, statin, type 2 diabetes mellitus, uncontrolled glycemia

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Authors: J. Zekri, N. Souilah, W. Abdelaziz, D. Alatou

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Our study shall focus on the ability of trees cork oak that showed vis-à-vis sensitivity to climate change, including late spring frosts. The combination of these factors resulted in damage alarmed, therefore forest ecosystems weakened trees that can affect their ability to support other abiotic and biotic stresses, For this we tested its tolerance to thermal variations and cold weather conditions by estimating some stress markers (quantification of proteins, RNA, soluble sugars) that are quantified to evaluate the cold tolerance of seedlings. Sowing of cork oak (Quercus suber L.) is grown in controlled conditions at 25° C ± 2° C in long days 16h. These seedlings are transferred at low temperatures between 5° C and -6° C for a period of 3 hours. Biochemical analyzes were performed in the various organs of the cork oak seedlings. Cool temperatures induced a significant accumulation of proline in different organs of seedlings and the optimum concentrations were observed in the roots with very high concentrations (4 times larger than those of the control). The accumulation of soluble sugars is significantly in stems and roots at 0° C. Protein concentrations are very high in leaves of both growth and high waves in rod at -4° C to -2° C. Tolerance cork oak seems to be at the thermal limit of -2°C. The concentration of these metabolites in the various organs showed the ability oak cork hardening during the winter.

Keywords: climate change, thermal change, semi-aride, biochemical markers, heat stress

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Authors: M. A. Zeinelabdeen, A. E. Abasaeed, M. H. Gaily, A. K. Sulieman, M. D. Putra

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The effect of temperature on the production of fructose and bioethanol from date syrup via selective fermentation by S. cerevisiae ATCC 36859 strain was studied. Various temperatures have been tested (27, 30 and 33 ᵒC). The fermentation experiments were conducted in a water shaker bath at the three temperatures under testing and 120 rpm. The results showed that a high fructose yield can be achieved at all temperatures under testing while the optimal is 27 ᵒC with 84% fructose yield. A high ethanol yield can be obtained for all temperatures under testing. However; the maximum biomass concentration and ethanol yield (86.22%) were obtained at 30 ᵒC.

Keywords: dates, ethanol, fructose, fermentation, S. cerevisiae

Procedia PDF Downloads 395

Authors: Sarit Rashkovits, Anat Drach- Zahavy

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The research considers the unresolved question regarding the link between nursing team accountability and team learning and the resulted team performance in nursing teams. Empirical findings reveal disappointing evidence regarding improvement in healthcare safety and quality. Therefore, there is a need in advancing managerial knowledge regarding the factors that enhance constant healthcare teams' proactive improvement efforts, meaning team learning. We first aim to identify the organizational resources that are needed for team learning in nursing teams; second, to test the moderating role of nursing teams' learning resources in the team accountability-team learning link; and third, to test the moderated mediation model suggesting that nursing teams' accountability affects team performance by enhancing team learning when relevant resources are available to the team. We point on the intervening role of three team learning resources, namely time availability, team autonomy and performance data on the relation between team accountability and team learning and test the proposed moderated mediation model on 44 nursing teams (462 nurses and 44 nursing managers). The results showed that, as was expected, there was a positive significant link between team accountability and team learning and the subsequent team performance when time availability and team autonomy were high rather than low. Nevertheless, the positive team accountability- team learning link was significant when team performance feedback was low rather than high. Accordingly, there was a positive mediated effect of team accountability on team performance via team learning when either time availability or team autonomy were high and the availability of team performance data was low. Nevertheless, this mediated effect was negative when time availability and team autonomy were low and the availability of team performance data was high. We conclude that nurturing team accountability is not enough for achieving nursing teams' learning and the subsequent improved team performance. Rather there is need to provide nursing teams with adequate time, autonomy, and be cautious with performance feedback, as the latter may motivate nursing teams to repeat routine work strategies rather than explore improved ones.

Keywords: nursing teams' accountability, nursing teams' learning, performance feedback, teams' autonomy

Procedia PDF Downloads 261

Authors: Sophio Kobauri, Tengiz Kantaria, Temur Kantaria, David Tugushi, Nina Kulikova, Ramaz Katsarava

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Polymeric disperse systems such as nanoparticles (NPs) are of high interest for numerous applications in contemporary medicine and nanobiotechnology to a considerable potential for treatment of many human diseases. The important technological advantages of NPs usage as drug carriers (nanocontainers) are their high stability, high carrier capacity, feasibility of encapsulation of both hydrophilic or hydrophobic substances, as well as a high variety of possible administration routes, including oral application and inhalation. NPs can also be designed to allow controlled (sustained) drug release from the matrix. These properties of NPs enable improvement of drug bioavailability and might allow drug dosage decrease. The targeted and controlled administration of drugs using NPs might also help to overcome drug resistance, which is one of the major obstacles in the control of epidemics. Various degradable and non-degradable polymers of both natural and synthetic origin have been used for NPs construction. One of the most promising for the design of NPs are amino acid-based biodegradable polymers (AABBPs) which can clear from the body after the fulfillment of their function. The AABBPs are composed of naturally occurring and non-toxic building blocks such as α-amino acids, fatty diols and dicarboxylic acids. The particles designed from these polymers are expected to have an improved bioavailability along with a high biocompatibility. The present work deals with a systematic study of the preparation of NPs by cost-effective polymer deposition/solvent displacement method using AABBPs. The influence of the nature and concentration of surfactants, concentration of organic phase (polymer solution), and the ratio organic phase/inorganic(water) phase, as well as of some other factors on the size of the fabricated NPs have been studied. It was established that depending on the used conditions the NPs size could be tuned within 40-330 nm. At the next step of this research was carried out an evaluation of biocompability and bioavailability of the synthesized NPs using a stable human cell culture line – A549. It was established that the obtained NPs are not only biocompatible but they stimulate the cell growth.

Keywords: amino acids, biodegradable polymers, bioavailability, nanoparticles

Procedia PDF Downloads 294

Authors: Jung-Ho Moon, Tae Kwon Ha

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Abstract—High temperature deformation behavior of cast Fe-20Cr-5Al alloy has been investigated in this study by performing tensile and compression tests at temperatures from 1100 to 1200oC. Rectangular ingots of which the dimensions were 300×300×100 in millimeter were cast using vacuum induction melting. Phase equilibrium was calculated using the FactSage®, thermodynamic software and database. Tensile strength of cast Fe-20Cr-5Al alloy was 4 MPa at 1200oC. With temperature decreased, tensile strength increased rapidly and reached up to 13 MPa at 1100oC. Elongation also increased from 18 to 80% with temperature decreased from 1200oC to 1100oC. Microstructure observation revealed that M23C6 carbide was precipitated along the grain boundary and within the matrix.

Keywords: 20 Cr-5Al ferritic stainless, high temperature deformation, aging treatment, microstructure, mechanical properties

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Authors: Moh Hanif Mubarok, Muhammad Rivai

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The public's response to quality rice is very high. So it is necessary to set minimum standards in checking the quality of rice. Most rice quality measurements still use manual methods, which are prone to errors due to limited human vision and the subjectivity of testers. So, a gas detection system can be a solution that has high effectiveness and subjectivity for solving current problems. The use of gas sensors in testing rice quality must pay attention to several parameters. The parameters measured in this research are the percentage of rice water content, gas concentration, output voltage, and measurement time. Therefore, this research was carried out to identify carbon dioxide (CO₂), nitrous oxide (N₂O) and methane (CH₄) gases in rice quality using a series of gas sensors using the Neural Network method.

Keywords: carbon dioxide, dinitrogen oxide, methane, semiconductor gas sensor, neural network

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Authors: Ayad Dalloo, Sulaf Dalloo

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Electrocardiogram (ECG) recording is prone to complications, on analysis by physicians, due to noise and artifacts, thus creating ambiguity leading to possible error of diagnosis. Such drawbacks may be overcome with the advent of high resolution Methods, such as Discrete Wavelet Analysis and Digital Signal Processing (DSP) techniques. This ECG signal analysis is implemented in three stages: ECG preprocessing, features extraction and classification with the aim of realizing high resolution ECG diagnosis and improved detection of abnormal conditions in the heart. The preprocessing stage involves removing spurious artifacts (noise), due to such factors as muscle contraction, motion, respiration, etc. ECG features are extracted by applying DSP and suggested sloping method techniques. These measured features represent peak amplitude values and intervals of P, Q, R, S, R’, and T waves on ECG, and other features such as ST elevation, QRS width, heart rate, electrical axis, QR and QT intervals. The classification is preformed using these extracted features and the criteria for cardiovascular diseases. The ECG diagnostic system is successfully applied to 12-lead ECG recordings for 12 cases. The system is provided with information to enable it diagnoses 15 different diseases. Physician’s and computer’s diagnoses are compared with 90% agreement, with respect to physician diagnosis, and the time taken for diagnosis is 2 seconds. All of these operations are programmed in Matlab environment.

Keywords: ECG diagnostic system, QRS detection, ECG baseline removal, cardiovascular diseases

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Authors: Arun Kumar Singh, Rupesh M. Das, Shailendra Saini

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The present work is an attempt to evaluate the sub-auroral ionospheric behavior under changing space weather conditions especially during high solar activity year 2014. In view of this, the GPS TEC along with Ionosonde data over Indian permanent scientific base 'Maitri', Antarctica (70°46′00″ S, 11°43′56″ E) has been utilized. The results suggested that the nature of ionospheric responses to the geomagnetic disturbances mainly depended upon the status of high latitudinal electro-dynamic processes along with the season of occurrence. Fortunately, in this study, both negative and positive ionospheric impact to the geomagnetic disturbances has been observed in a single year but in different seasons. The study reveals that the combination of equator-ward plasma transportation along with ionospheric compositional changes causes a negative ionospheric impact during summer and equinox seasons. However, the combination of pole-ward contraction of the oval region along with particle precipitation may lead to exhibiting positive ionospheric response during the winter season. Other than this, some Ionosonde based new experimental evidence also provided clear evidence of particle precipitation deep up to the low altitudinal ionospheric heights, i.e., up to E-layer by the sudden and strong appearance of E-layer at 100 km altitudes. The sudden appearance of E-layer along with a decrease in F-layer electron density suggested the dominance of NO⁺ over O⁺ at a considered region under geomagnetic disturbed condition. The strengthening of E-layer is responsible for modification of auroral electrojet and field-aligned current system. The present study provided a good scientific insight on sub-auroral ionospheric to the changing space weather condition.

Keywords: high latitude ionosphere, space weather, geomagnetic storms, sub-storm

Procedia PDF Downloads 162

Authors: Frank Jaksoni Mweta, Nozomu Adachi, Yoshikazu Todaka, Hirokazu Sato, Yuta Sato, Hiromi Miura, Masakazu Kobayashi, Chihiro Watanabe, Yoshiteru Aoyagi

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Advances in the consumption of hydrogen fuel increase demands of high strength steel pipes and storage tanks. However, high strength steels are highly sensitive to hydrogen embrittlement. Because the introduction of hydrogen into steel during the fabrication process or from the environment is unavoidable, it is essential to improve hydrogen embrittlement resistance of high strength steels through microstructural control. In the present study, the heterogeneous nanostructure with a tensile strength of about 1.8 GPa and the homogeneous nanostructure with a tensile strength of about 2.0 GPa of 316LN steels were generated after 92% heavy cold rolling and high-pressure torsion straining, respectively. The heterogeneous nanostructure is composed of twin domains, shear bands, and lamellar grains. The homogeneous nanostructure is composed of uniformly distributed ultrafine nanograins. The influence of heterogeneous and homogenous nanostructures on the hydrogen embrittlement resistance was investigated. The specimen for each nanostructure was electrochemically charged with hydrogen for 3, 6, 12, and 24 hours, respectively. Under the same hydrogen charging time, both nanostructures show almost the same concentration of the diffusible hydrogen based on the thermal desorption analysis. The tensile properties of the homogenous nanostructure were severely affected by the diffusible hydrogen. However, the diffusible hydrogen shows less impact on the tensile properties of the heterogeneous nanostructure. The difference in embrittlement behavior between the heterogeneous and homogeneous nanostructures was elucidated based on the mechanism of the cracks' growth observed in the tensile fractography. The hydrogen embrittlement was suppressed in the heterogeneous nanostructure because the twin domain became an obstacle for crack growth. The homogeneous nanostructure was not consisting an obstacle such as a twin domain; thus, the crack growth resistance was low in this nanostructure.

Keywords: diffusible hydrogen, heterogeneous nanostructure, homogeneous nanostructure, hydrogen embrittlement

Procedia PDF Downloads 118