Search results for: total leakage current
16871 Stereological Evaluation of Liver of Rabbit Fetuses After Transplantation of Human Wharton’s Jelly-Derived Mesenchymal Stromal/Stem Cells
Authors: Zahra Khodabandeh, Leila Rezaeian, Mohammad Amin Edalatmanesh, Asghar Mogheiseh, Nader Tanideh, Mehdi Dianatpour, Shahrokh Zare, Hossein Bordbar, Neda Baghban, Amin Tamadon
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Background: In-utero xenotransplantation of stem cells in abnormal fetuses effectively treats several genetic illnesses. Objective: The current research aimed to evaluate structural and morphological alterations in the liver of rabbit fetuses following xenotransplantation of human Wharton’s jelly-derived mesenchymal stromal cells (hWJ-MSCs) using a stereological technique. Methods: hWJ-MSCs were isolated from the human umbilical cord, and their authenticity was established by flow cytometry and differentiation. At gestational day 14, the rabbits were anesthetized, and hWJ-MSCs were injected into the uteri of 24 fetuses. Twenty-two fetuses were born successfully. Ten rabbit liver specimens were prepared from injected fetuses, including eight rabbits on day three following birth and two rabbits on the 21st post-natal day. The non-injected fetuses were considered positive controls. The livers of the control and hWJ-MSCs-treated rabbits were fixed, processed, stained, and examined through stereological approaches. Results: In the hWJ-MSCs-treated group, the mean liver weight and volume increased by 42% and 78% compared to the control group. The total volume of the hepatocytes increased by 63% and that of sinusoids by threefold in the treated rabbits. The total volume of the central veins increased by 70%. The total number corresponding to hepatocytes in the experimental group increased by 112% compared to the rabbits in the control. The total volume of the hepatocyte nuclei in the experimental group increased by 117% compared to the rabbits in the control. Conclusion: After xenotransplantation of human MSCs, host tissue microenvironments (here, the rabbit liver) were altered, and these included quantitative factors corresponding to the liver tissue and hepatocyte morphometric indices.Keywords: xenotransplantation, mesenchymal stromal, stem cell, Wharton ‘s jelly, liver
Procedia PDF Downloads 10116870 In vitro Assessment of Bioactive Properties and Dose-Dependent Antioxidant Activities of Commercial Grape Cultivars in Taiwan
Authors: Kandi Sridhar, Charles Albert Linton
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Grapes are excellent sources of bioactive compounds, which have been suggested to be responsible for lowering the risk of chronic diseases. Fresh and freeze-dried extracts of Kyoho and Jubilee, commercial grape varieties available in Taiwan and attractive for their quality berries, were investigated for their total phenolics and total flavonoids contents and related dose-dependent antioxidants properties using various in vitro assays. The efficiency of the extraction yield ranged from 7.10 % to 25.53 % (w/w), depending on solvent used. Fresh samples of Kyoho and Jubilee exhibited total polyphenolic contents (351.56 ± 23.08 and 328.67 ± 16.54 µg GAE/mL, respectively), whereas Kyoho freeze-dried methanol: water extracts contains the good levels of total flavonoids (4767.82 ± 22.20 µg QE/mL). Kyoho and Jubilee freeze-dried extracts exhibited the highest total flavonoid contents. There was a weak correlation between total phenolic and flavonoid assays (r= -0.05, R2 = 0.02, p > 0.05). Kyoho fresh and freeze-dried samples showed the DPPH (11.51 – 77.82 %), superoxide scavenging activity (33.61 – 81.95 %), and total antioxidant inhibition (92.01 – 99.28 %), respectively. Total flavonoids were statistically correlated with EC50 DPPH scavenging radicals (r =0.91, p < 0.01), EC50 nitric oxide (r = 0.25, p > 0.05), and EC50 lipid peroxidation radicals (r = 0.38, p > 0.05). These results suggested that the two commercial grape cultivars in Taiwan could be used as a good source of natural antioxidants. Thus, consumption of grapes as a source antioxidant might lower the risk of chronic diseases. Moreover, future studies will investigate and develop phenolic acid profile for the cultivars in Taiwan.Keywords: antioxidants, EC50 radical scavenging activity, grape cultivars, total phenolics
Procedia PDF Downloads 17816869 Optimisation of Extraction of Phenolic Compounds in Algerian Lavandula multifida, Algeria, NW
Authors: Mustapha Mahmoud Dif, Fouzia Benali-Toumi, Mohamed Benyahia, Sofiane Bouazza, Abbes Dellal, Slimane Baha
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L. multifida is applied to treat rheumatism and cold and has hypoglycemic and anti-inflammatory properties. The present study is to optimize the extraction of phenolic compounds in Algerian Lavandula multifida. The influences of parameters including temperature (decoction and maceration) and extraction time (15min to 45 min) on the flavonoids concentration are studied. The optimal conditions are determined and the quadratic response surfaces draw from the mathematical models. Total phenols were evaluated using Folin sicaltieu methods, total flavonoids were estimated using the Tri chloral aluminum method. The maximum concentration extracted, for total flavonoids, equal to 0.043 mg/g was achieved with decoction and extraction time of 41.55 min. However, for total phenol compounds highest concentration of 0.218 mg/g, is obtained with 45 min at 49.99°C.Keywords: L multifidi, phenolic content, optimization, time, temperature
Procedia PDF Downloads 42016868 Parametric Evaluation for the Optimization of Gastric Emptying Protocols Used in Health Care Institutions
Authors: Yakubu Adamu
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The aim of this research was to assess the factors contributing to the need for optimisation of the gastric emptying protocols in nuclear medicine and molecular imaging (SNMMI) procedures. The objective is to suggest whether optimisation is possible and provide supporting evidence for the current imaging protocols of gastric emptying examination used in nuclear medicine. The research involved the use of some selected patients with 30 dynamic series for the image processing using ImageJ, and by so doing, the calculated half-time, retention fraction to the 60 x1 minute, 5 minute and 10-minute protocol, and other sampling intervals were obtained. Results from the study IDs for the gastric emptying clearance half-time were classified into normal, abnormal fast, and abnormal slow categories. In the normal category, which represents 50% of the total gastric emptying image IDs processed, their clearance half-time was within the range of 49.5 to 86.6 minutes of the mean counts. Also, under the abnormal fast category, their clearance half-time fell between 21 to 43.3 minutes of the mean counts, representing 30% of the total gastric emptying image IDs processed, and the abnormal slow category had clearance half-time within the range of 138.6 to 138.6 minutes of the mean counts, representing 20%. The results indicated that the calculated retention fraction values from the 1, 5, and 10-minute sampling curves and the measured values of gastric emptying retention fraction from sampling curves of the study IDs had a normal retention fraction of <60% and decreased exponentially with an increase in time and it was evident with low percentages of retention fraction ratios of < 10% after the 4 hours. Thus, this study does not change categories suggesting that these values could feasibly be used instead of having to acquire actual images. Findings from the study suggest that the current gastric emptying protocol can be optimized by acquiring fewer images. The study recommended that the gastric emptying studies should be performed with imaging at a minimum of 0, 1, 2, and 4 hours after meal ingestion.Keywords: gastric emptying, retention fraction, clearance halftime, optimisation, protocol
Procedia PDF Downloads 516867 Intracranial Hypotension: A Brief Review of the Pathophysiology and Diagnostic Algorithm
Authors: Ana Bermudez de Castro Muela, Xiomara Santos Salas, Silvia Cayon Somacarrera
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The aim of this review is to explain what is the intracranial hypotension and its main causes, and also to approach to the diagnostic management in the different clinical situations, understanding radiological findings, and physiopathological substrate. An approach to the diagnostic management is presented: what are the guidelines to follow, the different tests available, and the typical findings. We review the myelo-CT and myelo-RM studies in patients with suspected CSF fistula or hypotension of unknown cause during the last 10 years in three centers. Signs of intracranial hypotension (subdural hygromas/hematomas, pachymeningeal enhancement, venous sinus engorgement, pituitary hyperemia, and lowering of the brain) that are evident in baseline CT and MRI are also sought. The intracranial hypotension is defined as a lower opening pressure of 6 cmH₂O. It is a relatively rare disorder with an annual incidence of 5 per 100.000, with a female to male ratio 2:1. The clinical features it’s an orthostatic headache, which is defined as development or aggravation of headache when patients move from a supine to an upright position and disappear or typically relieve after lay down. The etiology is a decrease in the amount of cerebrospinal fluid (CSF), usually by loss of it, either spontaneous or secondary (post-traumatic, post-surgical, systemic disease, post-lumbar puncture etc.) and rhinorrhea and/or otorrhea may exist. The pathophysiological mechanisms of hypotension and CSF hypertension are interrelated, as a situation of hypertension may lead to hypotension secondary to spontaneous CSF leakage. The diagnostic management of intracranial hypotension in our center includes, in the case of being spontaneous and without rhinorrhea and/or otorrhea and according to necessity, a range of available tests, which will be performed from less to more complex: cerebral CT, cerebral MRI and spine without contrast and CT/MRI with intrathecal contrast. If we are in a situation of intracranial hypotension with the presence of rhinorrhea/otorrhea, a sample can be obtained for the detection of b2-transferrin, which is found in the CSF physiologically, as well as sinus CT and cerebral MRI including constructive interference steady state (CISS) sequences. If necessary, cisternography studies are performed to locate the exact point of leakage. It is important to emphasize the significance of myelo-CT / MRI to establish the diagnosis and location of CSF leak, which is indispensable for therapeutic planning (whether surgical or not) in patients with more than one lesion or doubts in the baseline tests.Keywords: cerebrospinal fluid, neuroradiology brain, magnetic resonance imaging, fistula
Procedia PDF Downloads 12716866 Transient Signal Generator For Fault Indicator Testing
Authors: Mohamed Shaban, Ali Alfallah
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This paper describes an application for testing of a fault indicator but it could be used for other network protection testing. The application is created in the LabVIEW environment and consists of three parts. The first part of the application is determined for transient phenomenon generation and imitates voltage and current transient signal at ground fault originate. The second part allows to set sequences of trend for each current and voltage output signal, up to six trends for each phase. The last part of the application generates harmonic signal with continuously controllable amplitude of current or voltage output signal and phase shift of each signal can be changed there. Further any sub-harmonics and upper harmonics can be added to selected current output signalKeywords: signal generator-fault indicator, harmonic signal generator, voltage output
Procedia PDF Downloads 49516865 Critical Investigation on Performance of Polymeric Materials in Rehabilitation of Metallic Components
Authors: Parastou Kharazmi
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Failure and leakage of metallic components because of corrosion in infrastructure structures is a considerably problematic and expensive issue and the traditional solution of replacing the component is costly and time-consuming. Rehabilitation techniques by using advanced polymeric materials are an alternative solution towards this problem. This paper provides a summary of analyses on relined rehabilitated metallic samples after exposure in practice and real condition to study the composite material performance when it is exposed to water, heat and chemicals in real condition. The study was carried out by using different test methods such as microscopy, thermal and chemical as well as mechanical analyses.Keywords: composite, material, rehabilitation, structure
Procedia PDF Downloads 23616864 Assessing Professionalism, Communication, and Collaboration among Emergency Physicians by Implementing a 360-Degree Evaluation
Authors: Ahmed Al Ansari, Khalid Al Khalifa
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Objective: Multisource feedback (MSF), also called the 360-Degree evaluation is an evaluation process by which questionnaires are distributed amongst medical peers and colleagues to assess physician performance from different sources other than the attending or the supervising physicians. The aim of this study was to design, implement, and evaluate a 360-Degree process in assessing emergency physicians trainee in the Kingdom of Bahrain. Method: The study was undertaken in Bahrain Defense Force Hospital which is a military teaching hospital in the Kingdom of Bahrain. Thirty emergency physicians (who represent the total population of the emergency physicians in our hospital) were assessed in this study. We developed an instrument modified from the Physician achievement review instrument PAR which was used to assess Physician in Alberta. We focused in our instrument to assess professionalism, communication skills and collaboration only. To achieve face and content validity, table of specification was constructed and a working group was involved in constructing the instrument. Expert opinion was considered as well. The instrument consisted of 39 items; were 15 items to assess professionalism, 13 items to assess communication skills, and 11 items to assess collaboration. Each emergency physicians was evaluated with 3 groups of raters, 4 Medical colleague emergency physicians, 4 medical colleague who are considered referral physicians from different departments, and 4 Coworkers from the emergency department. Independent administrative team was formed to carry on the responsibility of distributing the instruments and collecting them in closed envelopes. Each envelope was consisted of that instrument and a guide for the implementation of the MSF and the purpose of the study. Results: A total of 30 emergency physicians 16 males and 14 females who represent the total number of the emergency physicians in our hospital were assessed. The total collected forms is 269, were 105 surveys from coworkers working in emergency department, 93 surveys from medical colleague emergency physicians, and 116 surveys from referral physicians from different departments. The total mean response rates were 71.2%. The whole instrument was found to be suitable for factor analysis (KMO = 0.967; Bartlett test significant, p<0.00). Factor analysis showed that the data on the questionnaire decomposed into three factors which counted for 72.6% of the total variance: professionalism, collaboration, and communication. Reliability analysis indicated that the instrument full scale had high internal consistency (Cronbach’s α 0.98). The generalizability coefficients (Ep2) were 0.71 for the surveys. Conclusions: Based on the present results, the current instruments and procedures have high reliability, validity, and feasibility in assessing emergency physicians trainee in the emergency room.Keywords: MSF system, emergency, validity, generalizability
Procedia PDF Downloads 35716863 Assessing the Correlation between Environmental Awareness and Variability of Employees’ Positions in Aviation and Aerospace Industries
Authors: Eva Maleviti, Evan Stamoulis
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This paper is part of a wider research project, on environmental management in aviation and aerospace industries. The core elements of this research are the level of knowledge, awareness, applicability of environmental management systems, according to employees’ perspectives. This paper focuses at employees’ level of environmental awareness. The main scope of this research is to evaluate the level of environmental awareness and the adoption of environmental management practices. The primary scope of the research is to define a method to quantify the key indicators that would improve the implementation of environmental management. The opinion of people employed in aviation industry is considered, based on the versatility of their working positions. Up to this stage, 330 respondents have participated globally in the current research. This study uses a questionnaire survey to gain an understanding of the views and attitudes of aerospace staff toward environmental management. The results are analyzed through a quantitative approach using SPSS. The statistical significance shows that the data could follow the same distribution as the distribution of the total population that the sample belongs. As of the above, the number of respondents constitutes a representative sample of the total population. A descriptive analysis is presented. According to the responses given in the survey, the data are analyzed according to the working positions and the characteristics of each position that all the respondents hold. The results demonstrate that the level of environmental awareness is immediately linked with the employees’ positions. Managerial/post holder positions, as expected have, a higher level of environmental awareness. However, the level of applicability of environmental practices by the same group is considered low. The other working groups show variability in environmental awareness, which also depends on their operating task and the applicability or not of environmental practices. Flight operations and engineering/maintenance employees, that their tasks involve higher safety considerations, there are more reluctant in applying environmental practices in their positions. In the current paper an analysis of the data collection is presented, correlating them with the working positions and responsibilities of respondents.Keywords: environmental awareness, environmental management, sustainability, sustainable aviation
Procedia PDF Downloads 45616862 Experimental Investigation on the Fire Performance of Corrugated Sandwich Panels made from Renewable Material
Authors: Avishek Chanda, Nam Kyeun Kim, Debes Bhattacharyya
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The use of renewable substitutes in various semi-structural and structural applications has experienced an increase since the last few decades. Sandwich panels have been used for many decades, although research on understanding the effects of the core structures on the panels’ fire-reaction properties is limited. The current work investigates the fire-performance of a corrugated sandwich panel made from renewable, biodegradable, and sustainable material, plywood. The bench-scale fire testing apparatus, cone-calorimeter, was employed to evaluate the required fire-reaction properties of the sandwich core in a panel configuration, with three corrugated layers glued together with face-sheets under a heat irradiance of 50 kW/m2. The study helped in documenting a unique heat release trend associated with the fire performance of the 3-layered corrugated sandwich panels and in understanding the structural stability of the samples in the event of a fire. Furthermore, the total peak heat release rate was observed to be around 421 kW/m2, which is significantly low compared to many polymeric materials in the literature. The total smoke production was also perceived to be very limited compared to other structural materials, and the total heat release was also nominal. The time to ignition of 21.7 s further outlined the advantages of using the plywood component since polymeric composites, even with flame-retardant additives, tend to ignite faster. Overall, the corrugated plywood sandwich panels had significant fire-reaction properties and could have important structural applications. The possible use of structural panels made from bio-degradable material opens a new avenue for the use of similar structures in sandwich panel preparation.Keywords: corrugated sandwich panel, fire-reaction properties, plywood, renewable material
Procedia PDF Downloads 15616861 Voltage and Current Control of Microgrid in Grid Connected and Islanded Modes
Authors: Megha Chavda, Parth Thummar, Rahul Ghetia
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This paper presents the voltage and current control of microgrid accompanied by the synchronization of microgrid with the main utility grid in both islanded and grid-connected modes. Distributed Energy Resources (DERs) satisfy the wide-spread power demand of consumer by behaving as a micro source for a low voltage (LV) grid or microgrid. Synchronization of the microgrid with the main utility grid is done using PLL and PWM gate pulse generation technique is used for the Voltage Source Converter. Potential Function method achieves the voltage and current control of this microgrid in both islanded and grid-connected modes. A low voltage grid consisting of three distributed generators (DG) is considered for the study and is simulated in time-domain using PSCAD/EMTDC software. The simulation results depict the appropriateness of voltage and current control of microgrid and synchronization of microgrid with the medium voltage (MV) grid.Keywords: microgrid, distributed energy resources, voltage and current control, voltage source converter, pulse width modulation, phase locked loop
Procedia PDF Downloads 41416860 Improvement of Process Competitiveness Using Intelligent Reference Models
Authors: Julio Macedo
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Several methodologies are now available to conceive the improvements of a process so that it becomes competitive as for example total quality, process reengineering, six sigma, define measure analysis improvement control method. These improvements are of different nature and can be external to the process represented by an optimization model or a discrete simulation model. In addition, the process stakeholders are several and have different desired performances for the process. Hence, the methodologies above do not have a tool to aid in the conception of the required improvements. In order to fill this void we suggest the use of intelligent reference models. A reference model is a set of qualitative differential equations and an objective function that minimizes the gap between the current and the desired performance indexes of the process. The reference models are intelligent so when they receive the current state of the problematic process and the desired performance indexes they generate the required improvements for the problematic process. The reference models are fuzzy cognitive maps added with an objective function and trained using the improvements implemented by the high performance firms. Experiments done in a set of students show the reference models allow them to conceive more improvements than students that do not use these models.Keywords: continuous improvement, fuzzy cognitive maps, process competitiveness, qualitative simulation, system dynamics
Procedia PDF Downloads 8716859 Comparison between FEM Simulation and Experiment of Temperature Rise in Power Transformer Inner Steel Plate
Authors: Byung hyun Bae
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In power transformer, leakage magnetic flux generate temperature rise of inner steel plate. Sometimes, this temperature rise can be serious problem. If temperature of steel plate is over critical point, harmful gas will be generated in the tank. And this gas can be a reason of fire, explosion and life decrease. So, temperature rise forecasting of steel plate is very important at the design stage of power transformer. To improve accuracy of forecasting of temperature rise, comparison between simulation and experiment achieved in this paper.Keywords: power transformer, steel plate, temperature rise, experiment, simulation
Procedia PDF Downloads 49516858 Indigenous Patch Clamp Technique: Design of Highly Sensitive Amplifier Circuit for Measuring and Monitoring of Real Time Ultra Low Ionic Current through Cellular Gates
Authors: Moez ul Hassan, Bushra Noman, Sarmad Hameed, Shahab Mehmood, Asma Bashir
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The importance of Noble prize winning “Patch Clamp Technique” is well documented. However, Patch Clamp Technique is very expensive and hence hinders research in developing countries. In this paper, detection, processing and recording of ultra low current from induced cells by using transimpedence amplifier is described. The sensitivity of the proposed amplifier is in the range of femto amperes (fA). Capacitive-feedback is used with active load to obtain a 20MΩ transimpedance gain. The challenging task in designing includes achieving adequate performance in gain, noise immunity and stability. The circuit designed by the authors was able to measure current in the rangeof 300fA to 100pA. Adequate performance shown by the amplifier with different input current and outcome result was found to be within the acceptable error range. Results were recorded using LabVIEW 8.5®for further research.Keywords: drug discovery, ionic current, operational amplifier, patch clamp
Procedia PDF Downloads 51916857 Challenges of Management of Acute Pancreatitis in Low Resource Setting
Authors: Md. Shakhawat Hossain, Jimma Hossain, Md. Naushad Ali
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Acute pancreatitis is a dangerous medical emergency in the practice of gastroenterology. Management of acute pancreatitis needs multidisciplinary approach with support starts from emergency to ICU. So, there is a chance of mismanagement in every steps, especially in low resource settings. Other factors such as patient’s financial condition, education, social custom, transport facility, referral system from periphery may also challenge the current guidelines for management. The present study is intended to determine the clinico-pathological profile, severity assessment and challenges of management of acute pancreatitis in a government laid tertiary care hospital to image the real scenario of management in a low resource place. A total 100 patients of acute pancreatitis were studied in this prospective study, held in the Department of Gastroenterology, Rangpur medical college hospital, Bangladesh from July 2017 to July 2018 within one year. Regarding severity, 85 % of the patients were mild, whereas 13 were moderately severe, and 2 had severe acute pancreatitis according to the revised Atlanta criteria. The most common etiologies of acute pancreatitis in our study were gall stone (15%) and biliary sludge (15%), whereas 54% were idiopathic. The most common challenges we faced were delay in hospital admission (59%) and delay in hospital diagnosis (20%). Others are non-adherence of patient party, and lack of investigation facility, physician’s poor knowledge about current guidelines. We were able to give early aggressive fluid to only 18% of patients as per current guideline. Conclusion: Management of acute pancreatitis as per guideline is challenging when optimum facility is lacking. So, modified guidelines for assessment and management of acute pancreatitis should be prepared for low resource setting.Keywords: acute pancreatitis, challenges of management, severity, prognosis
Procedia PDF Downloads 13016856 Design of Distribution Network for Gas Cylinders in Jordan
Authors: Hazem J. Smadi
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Performance of a supply chain is directly related to a distribution network that entails the location of storing materials or products and how products are delivered to the end customer through different stages in the supply chain. This study analyses the current distribution network used for delivering gas cylinders to end customer in Jordan. Evaluation of current distribution has been conducted across customer service components. A modification on the current distribution network in terms of central warehousing in each city in the country improves the response time and customer experience.Keywords: distribution network, gas cylinder, Jordan, supply chain
Procedia PDF Downloads 46016855 The Use of Global Positioning Systems to Evaluate the Effect of Protein and Carbohydrate Supplementation on Collegiate Soccer Performance
Authors: Joshua Bradley, Matthew Buns
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This study aimed to identify the effect of concurrent nutritional supplementation on soccer performance as players ingested either carbohydrate CHO (52 g of Cytocarb Maltodextrin) or a combined carbohydrate and protein PRO (Muscle Milk Pro Series 17g CHO + 50 g PRO liquid) supplement. Twelve male, junior college soccer players (age: 18 ± 6 years, wt. 73.3 ± 8.6 kg) completed three trials wearing global positioning systems (GPS) to measure total running distance and sprinting distance during soccer simulation games. The first match simulation was a baseline match with no supplementation. One hour prior to the second match, simulation players were randomly assigned to one of two supplemental groups CHO or CHO + PRO. A repeated measures ANOVA with a Greenhouse-Geisser correction revealed a statistically significant increase in the total distance run for the CHO supplementation group in comparison to the CHO + PRO group (10.19 ± .200 km vs. 9.77± .194km, p = .035). Although the total running distance was meaningfully influenced by the supplementation, the pattern of response for total sprinting distance was not influenced by supplementation. There was a decline in sprinting distance and total running distance from first half to second half, both for the control (M = -0.01 km, SD = 0.17) and CHO supplementation group (-0.04 km, SD = .19), although these differences were not statistically meaningful. There was a positive correlation between sprinting distance and total distance, which was statistically significant (r = -.514, n = 36, p = .01) In conclusion, supplementation influenced the pattern of activity and demonstrated between-trial differences.Keywords: GPS, nutrition, simulation, supplementation
Procedia PDF Downloads 14616854 Design and Analysis of a Piezoelectric-Based AC Current Measuring Sensor
Authors: Easa Ali Abbasi, Akbar Allahverdizadeh, Reza Jahangiri, Behnam Dadashzadeh
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Electrical current measurement is a suitable method for the performance determination of electrical devices. There are two contact and noncontact methods in this measuring process. Contact method has some disadvantages like having direct connection with wire which may endamage the system. Thus, in this paper, a bimorph piezoelectric cantilever beam which has a permanent magnet on its free end is used to measure electrical current in a noncontact way. In mathematical modeling, based on Galerkin method, the governing equation of the cantilever beam is solved, and the equation presenting the relation between applied force and beam’s output voltage is presented. Magnetic force resulting from current carrying wire is considered as the external excitation force of the system. The results are compared with other references in order to demonstrate the accuracy of the mathematical model. Finally, the effects of geometric parameters on the output voltage and natural frequency are presented.Keywords: cantilever beam, electrical current measurement, forced excitation, piezoelectric
Procedia PDF Downloads 23216853 Proximate and Mineral Composition of Chicken Giblets from Vojvodina, Northern Serbia
Authors: M. R. Jokanović, V. M. Tomović, M. T. Jović, S. B. Škaljac, B. V. Šojić, P. M. Ikonić, T. A. Tasić
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Proximate (moisture, protein, total fat, total ash) and mineral (K, P, Na, Mg, Ca, Zn, Fe, Cu and Mn) composition of chicken giblets (heart, liver and gizzard) were investigated. Phosphorous content, as well as proximate composition, were determined according to recommended ISO methods. The content of all elements, except phosphorus, of the giblets tissues were determined using inductively coupled plasma-optical emission spectrometry (ICP-OES), after dry ashing mineralization. Regarding proximate composition heart was the highest in total fat content, and the lowest in protein content. Liver was the highest in protein and total ash content, while gizzard was the highest in moisture and the lowest in total fat content. Regarding mineral composition liver was the highest for K, P, Ca, Mg, Fe, Zn, Cu, and Mn, while heart was the highest for Na content. The contents of almost all investigated minerals in analysed giblets tissues of chickens from Vojvodina were similar to values reported in the literature, i.e. in national food composition databases of other countries.Keywords: chicken giblets, proximate composition, mineral composition, inductively coupled plasma-optical emission spectrometry (ICP-OES)
Procedia PDF Downloads 45116852 Pre-Shared Key Distribution Algorithms' Attacks for Body Area Networks: A Survey
Authors: Priti Kumari, Tricha Anjali
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Body Area Networks (BANs) have emerged as the most promising technology for pervasive health care applications. Since they facilitate communication of very sensitive health data, information leakage in such networks can put human life at risk, and hence security inside BANs is a critical issue. Safe distribution and periodic refreshment of cryptographic keys are needed to ensure the highest level of security. In this paper, we focus on the key distribution techniques and how they are categorized for BAN. The state-of-art pre-shared key distribution algorithms are surveyed. Possible attacks on algorithms are demonstrated with examples.Keywords: attacks, body area network, key distribution, key refreshment, pre-shared keys
Procedia PDF Downloads 36416851 Microbial and Meiofaunal Dynamics in the Intertidal Sediments of the Northern Red Sea
Authors: Hamed A. El-Serehy, Khaled A. Al-Rasheid, Fahad A Al-Misned
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The meiofaunal population fluctuation, microbial dynamic and the composition of the sedimentary organic matter were investigated seasonally in the Egyptian shores along the northern part of Red Sea. Total meiofaunal population densities were extremely low with an annual average of 109 ±26 ind./10 cm2 and largely dominated by nematodes (on annual average from 52% to 94% of total meiofaunal density). The benthic microbial population densities ranged from 0.26±0.02 x 108 to 102.67±18.62 x 108/g dry sediment. Total sedimentary organic matter concentrations varied between 5.8 and 11.6 mg/g and the organic carbon, which was measured as summation of the carbohydrates, proteins and lipids, accounted for only a small fraction of being 32 % of the total organic matter. Chlorophyll a attained very low values and fluctuated between 2 and 11 µg/g. The very low chlorophyll a concentration in the Egyptian coasts along the Red Sea can suggest that the sedimentary organic matter along the Egyptian coasts is dominated by organic detrital and heterotrophic bacteria on one hand, and do not promote carbon transfer towards the higher trophic level on the other hand. However, the present study indicates that the existing of well diversified meiofaunal group, with a total of ten meiofaunal taxa, can serve as food for higher trophic levels in the Red Sea marine ecosystem.Keywords: bacteria, meiofauna, intertidal sediments, Red Sea
Procedia PDF Downloads 42516850 Evaluation of the Capabilities of Saccharomyces cerevisiae and Lactobacillus plantarum in Improvement of Total Phenolic Content and Antioxidant Activity in Carob Kibble
Authors: Thi Huong Vu, Vijay Jayasena, Zhongxiang Fang, Gary Dykes
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Carob kibble has recently received attention due to the presence of high level of polyphenol antioxidants. The capacity of microorganisms to improve antioxidant activities and total phenolics in carob kibble was investigated in the study. Two types of microorganisms including lactic acid bacteria Lactobacillus plantarum (L. plantarum) and yeast Saccharomyces cerevisiae (S. cerevisiae) were used in single and in their combination as starters. The total phenolic content was determined by the Folin–Ciocalteu method. Antioxidant activities were assessed scavenging capacity using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS). The study found that S. cerevisiae alone considerably improved 55% total phenolics content at 15 h, while L. plantarum caused in a loss of 20% through the process. Antioxidant capacity of the yeast-fermented samples significantly increased by 43 % and 10 % in ABTS and DPPH assays, respectively. However, reduction of 13 % and 32 % inhibition were recorded in the carob treated with L. plantarum. In the combination of S. cerevisiae and L. plantarum (1:1), both total phenolic content and antioxidant activity of carob kibble were a similar trend as these of S. cerevisiae single, but a lower improvement. The antioxidant power of the extracts was linearly correlated to their total phenolic contents (R=0.75). The results suggested that S. cerevisiae alone was the better for enhancement of both total phenolic content and antioxidant activity in carob kibble using submerged fermentation. The efficiency of fermentation reached the highest at 15h. Thus submerged fermentation with S. cerevisiae offers a tool with simple and cost effective to further increase the bioactive potential of carob kibble, which is in use for food, cosmetic and pharmaceutical industries.Keywords: antioxidant activity, carob kibble, lactobacillus plantarum, saccharomyces cerevisiae, total phenolics
Procedia PDF Downloads 29016849 Full-Potential Investigation of the Electronic and Magnetic Properties of CdCoTe and CdMnTe Diluted Magnetic Semiconductors
Authors: A.Zitouni, S.Bentata, B.Bouadjemi, T.Lantri, W. Benstaali, Z.Aziz, S.Cherid
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We investigate the structural, electronic and magnetic properties of the diluted magnetic semiconductors (DMSs) CdCoTe and CdMnTe in the zinc blende phase with 25% of Co and Mn. The calculations are performed by the recent ab initio full potential augmented plane waves (FP_L/APW) method within the spin polarized density-functional theory (DFT) and the generalized gradient approximation GGA. Structural properties are determined from the total energy calculations and we found that these compounds are stable in the ferromagnetic phase. We discuss the electronic structures, total and partial densities of states and total magnetic moments. The calculated densities of states presented in this study identify the half-metallic of CdCoTe and CdMnTe.Keywords: electronic structure, half-metallic, magnetic moment, total and partial densities of states
Procedia PDF Downloads 49716848 Calculating Quantity of Steel Bar Placed in Mesh Form in a Circular Slab or Dome
Authors: Karam Chand Gupta
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When steel reinforcement is placed in mesh form in circular concrete slab at base or domes at top in case of over head service reservoir or any other structure, it is difficult to estimate/measure the total quantity of steel that would be needed or placed. For the purpose of calculating the total length of the steel bars, at present, the practice is – the length of each bar is measured and then added up. This is tiresome and time consuming process. I have derived a mathematics formula with the help of which we can calculate in one line the quantity of total steel that will be needed. This will not only make it easy and time saving but also avoids any error in making entries and calculations.Keywords: dome, mesh, slab, steel
Procedia PDF Downloads 68116847 The Impact of Exchange Rate Volatility on Real Total Export and Sub-Categories of Real Total Export of Malaysia
Authors: Wong Hock Tsen
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This study aims to investigate the impact of exchange rate volatility on real export in Malaysia. The moving standard deviation with order three (MSD(3)) is used for the measurement of exchange rate volatility. The conventional and partially asymmetric autoregressive distributed lag (ARDL) models are used in the estimations. This study finds exchange rate volatility to have significant impact on real total export and some sub-categories of real total export. Moreover, this study finds that the positive or negative exchange rate volatility tends to have positive or negative impact on real export. Exchange rate volatility can be harmful to export of Malaysia.Keywords: exchange rate volatility, autoregressive distributed lag, export, Malaysia
Procedia PDF Downloads 32416846 Prevalence Determination of Hepatitis D Virus Genotypes among HBsAg Positive Patients in Kerman Province of Iran
Authors: Khabat Barkhordari, Ali Mohammad Arabzadeh
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Hepatitis delta virus (HDV) is a RNA virus that needs the function of hepatitis B virus (HBV) for its propagation and assembly. Infection by HDV can occur spontaneously with HBV infection and cause acute hepatitis or develop as secondary infection in HBV suffering patients. Based on genome sequence analysis, HDV has several genotypes which show broad geographic and diverse clinical features. The aim of current study is determine the prevalence of hepatitis delta virus genotype in patients with positive HBsAg in Kerman province of Iran. This cross-sectional study a total of 400 patients with HBV infection attending the clinic center of Besat from 2012 to 2014 were included. We carried out ELISA to detect anti-HDV antibodies. Those testing positive were analyzed further for HDV-RNA and for genotyping using restriction fragment length polymorphism (RFLP) and RT-nested PCR- sequencing. Among 400 patients in this study, 67 cases (16.75 %) were containing anti-HDV antibody which we found HDV RNA in just 7 (1.75%) serum samples. Analysis of these 7 positive HDV showed that all of them have genotype I. According to current study the HDV prevalence in Kerman is higher than the reported prevalence of 6.6% for Iran as a whole and clade 1 (genotype 1) is the predominant clade of HDV in Kerman.Keywords: genotyping, hepatitis delta virus, molecular epidemiology, Kerman, Iran
Procedia PDF Downloads 29416845 Behavior of Current in a Semiconductor Nanostructure under Influence of Embedded Quantum Dots
Authors: H. Paredes Gutiérrez, S. T. Pérez-Merchancano
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Motivated by recent experimental and theoretical developments, we investigate the influence of embedded quantum dot (EQD) of different geometries (lens, ring and pyramidal) in a double barrier heterostructure (DBH). We work with a general theory of quantum transport that accounts the tight-binding model for the spin dependent resonant tunneling in a semiconductor nanostructure, and Rashba spin orbital to study the spin orbit coupling. In this context, we use the second quantization theory for Rashba effect and the standard Green functions method. We calculate the current density as a function of the voltage without and in the presence of quantum dots. In the second case, we considered the size and shape of the quantum dot, and in the two cases, we worked considering the spin polarization affected by external electric fields. We found that the EQD generates significant changes in current when we consider different morphologies of EQD, as those described above. The first thing shown is that the current decreases significantly, such as the geometry of EQD is changed, prevailing the geometrical confinement. Likewise, we see that the current density decreases when the voltage is increased, showing that the quantum system studied here is more efficient when the morphology of the quantum dot changes.Keywords: quantum semiconductors, nanostructures, quantum dots, spin polarization
Procedia PDF Downloads 27316844 A Comparative Study on Optimized Bias Current Density Performance of Cubic ZnB-GaN with Hexagonal 4H-SiC Based Impatts
Authors: Arnab Majumdar, Srimani Sen
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In this paper, a vivid simulated study has been made on 35 GHz Ka-band window frequency in order to judge and compare the DC and high frequency properties of cubic ZnB-GaN with the existing hexagonal 4H-SiC. A flat profile p+pnn+ DDR structure of impatt is chosen and is optimized at a particular bias current density with respect to efficiency and output power taking into consideration the effect of mobile space charge also. The simulated results obtained reveals the strong potentiality of impatts based on both cubic ZnB-GaN and hexagonal 4H-SiC. The DC-to-millimeter wave conversion efficiency for cubic ZnB-GaN impatt obtained is 50% with an estimated output power of 2.83 W at an optimized bias current density of 2.5×108 A/m2. The conversion efficiency and estimated output power in case of hexagonal 4H-SiC impatt obtained is 22.34% and 40 W respectively at an optimum bias current density of 0.06×108 A/m2.Keywords: cubic ZnB-GaN, hexagonal 4H-SiC, double drift impatt diode, millimetre wave, optimised bias current density, wide band gap semiconductor
Procedia PDF Downloads 35916843 Effect of Initial pH and Fermentation Duration on Total Phenolic Content and Antioxidant Activity of Carob Kibble Fermented with Saccharomyces cerevisiae
Authors: Thi Huong Vu, Haelee Fenton, Thi Huong Tra Nguyen, Gary Dykes
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In the present study, a submerged fermentation of carob kibble with Saccharomyces cerevisiae (S. cerevisiae) was performed. The total phenolic content and antioxidant activity in fermented carob kibble were determined by Folin–Ciocalteu method and scavenging capacity using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS). The study showed that S. cerevisiae improved total phenolic content by 45 % and 50 % in acetone and water extracts respectively. Similarly, the antioxidant capacity of water extracts increased by 25 % and 41%, while acetone extracts indicated by 70% and 80% in DPPH and ABTS respectively. It is also found that initial pH 7.0 was more effective in improvement of total phenolic content and antioxidant activity. The efficiency of treatment was recorded at 15 h. This report suggested that submerged fermentation with S. cerevisiae is a potential and cost effective manner to further increase bioactive compounds in carob kibble, which are in use for food, cosmetic and pharmaceutical industries.Keywords: antioxidant activity, carob kibble, saccharomyces cerevisiae, submerged fermentation, total phenolics
Procedia PDF Downloads 30616842 0.13-µm Complementary Metal-Oxide Semiconductor Vector Modulator for Beamforming System
Authors: J. S. Kim
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This paper presents a 0.13-µm Complementary Metal-Oxide Semiconductor (CMOS) vector modulator for beamforming system. The vector modulator features a 360° phase and gain range of -10 dB to 10 dB with a root mean square phase and amplitude error of only 2.2° and 0.45 dB, respectively. These features make it a suitable for wireless backhaul system in the 5 GHz industrial, scientific, and medical (ISM) bands. It draws a current of 20.4 mA from a 1.2 V supply. The total chip size is 1.87x1.34 mm².Keywords: CMOS, vector modulator, beamforming, 802.11ac
Procedia PDF Downloads 210