Search results for: stiffener length

Authors: Rong Li, Brian D. Wirth, Bing Liu

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Graphite is the matrix, and structural material in the high temperature gas-cooled reactor exhibits an irradiation response. It is of significant importance to analyze the defect production and evaluate the role of graphite under irradiation. A vast experimental literature exists for graphite on the dimensional change, mechanical properties, and thermal behavior. However, simulations have not been applied to the atomistic perspective. Remarkably few molecular dynamics simulations have been performed to study the irradiation response in graphite. In this paper, irradiation-induced damage cascades in graphite were investigated with molecular dynamics simulation. Statistical results of the graphite defects were obtained by sampling a wide energy range (1–30 KeV) and 10 different runs for every cascade simulation with different random number generator seeds to the velocity scaling thermostat function. The chemical bonding in carbon was described using the adaptive intermolecular reactive empirical bond-order potential (AIREBO) potential coupled with the standard Ziegler–Biersack–Littmack (ZBL) potential to describe close-range pair interactions. This study focused on analyzing the number of defects, the final cascade morphology and the distribution of defect clusters in space, the length-scale cascade properties such as the cascade length and the range of primary knock-on atom (PKA), and graphite mechanical properties’ variation. It can be concluded that the number of surviving Frenkel pairs increased remarkably with the increasing initial PKA energy but did not exhibit a thermal spike at slightly lower energies in this paper. The PKA range and cascade length approximately linearly with energy which indicated that increasing the PKA initial energy will come at expensive computation cost such as 30KeV in this study. The cascade morphology and the distribution of defect clusters in space mainly related to the PKA energy meanwhile the temperature effect was relatively negligible. The simulations are in agreement with known experimental results and the Kinchin-Pease model, which can help to understand the graphite damage cascades and lifetime span under irradiation and provide a direction to the designs of these kinds of structural materials in the future reactors.

Keywords: graphite damage cascade, molecular dynamics, cascade morphology, cascade distribution

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Authors: Diana Ruth Caga-Anan

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Classroom management is a critical skill but the styles are constantly evolving. It is constantly under pressure particularly in the college education level due to diversity in student profiles, modes of delivery, and marketization of higher education. This study sought to analyze the extent of implementation of classroom management practices (CMPs) of the college instructors of the Hotel, Restaurant, and Institution Management of a premier university in the Philippines. It was also determined if their length of teaching affects their classroom management style. A questionnaire with sixteen 'evidenced-based' CMPs grouped into five critical features of classroom management, adopted from the literature search of Simonsen et al. (2008), was administered to 4 instructor-respondents and to their 88 students. Weighted mean scores of each of the CMPs revealed that there were differences between the instructors’ self-scores and their students’ ratings on their implementation of CMPs. The critical feature of classroom management 'actively engage students in observable ways' got the highest mean score, corresponding to 'always' from the instructors’ self-rating and 'frequently' from their students’ ratings. However, 'use a continuum of strategies to respond to inappropriate behaviors' got the lowest scores from both the instructors and their students corresponding only to 'occasionally'. Analysis of variance showed that the only CMP affected by the length of teaching is the practice of 'prompting students to respond'. Based on the findings, some recommendations for the instructors to improve on the critical feature where they scored low are discussed and suggestions are included for future research.

Keywords: classroom management, CMPs, critical features, evidence-based classroom management practices

Procedia PDF Downloads 152

Authors: W. T. A. Mohammed, M. Eltaeb, R. Kashani

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The first bending modes of tall asymmetric structures in the two lateral X and Y-directions have two different natural frequencies. To add tuned damping to these bending modes, one needs to either a) use two pendulum-tuned mass dampers (PTMDs) with one tuning frequency, each PTMD targeting one of the bending modes, or b) use one PTMD with two tuning frequencies (one in each lateral directions). Option (a), being more massive, requiring more space, and being more expensive, is less attractive than option (b). Considering that the tuning frequency of a pendulum depends mainly on the pendulum length, one way of realizing option (b) is by constraining the swinging length of the pendulum in one direction but not in the other; such PTMD is dubbed passive Bi-PTMD. Alternatively, option (b) can be realized by actively setting the tuning frequencies of the PTMD in the two directions. In this work, accurate physical models of passive Bi-PTMD and active PTMD are developed and incorporated into the numerical model of a tall asymmetric structure. The model of PTMDs plus structure is used for a)synthesizing such PTMDs for particular applications and b)evaluating their damping effectiveness in mitigating the dynamic lateral responses of their target asymmetric structures, perturbed by wind load in X and Y-directions. Depending on how elaborate the control scheme is, the active PTMD can either be made to yield the same damping effectiveness as the passive Bi-PTMD of the same size or the passive Bi-TMD twice as massive as the active PTMD.

Keywords: active tuned mass damper, high-rise building, multi-frequency tuning, vibration control

Procedia PDF Downloads 78

Authors: Ahmed M. Eed, Adam H. Burgoyne

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Jojoba (Simmondsia chinensis (Link) Schneider), is a desert shrub which tolerates saline, alkyle soils and drought. The seeds contain a characteristic liquid wax of economic importance in industry as a machine lubricant and cosmetics. A major problem in seed propagation is that jojoba is a dioecious plant whose sex is not easily determined prior to flowering (3-4 years from germination). To overcome this phenomenon, asexual propagation using vegetative methods such as cutting can be used. This research was conducted to find out the effect of different Plant Growth Regulators (PGRs) and rooting media on Jojoba rhizogenesis. An experiment was carried out in a Factorial Completely Randomized Design (FCRD) with three replications, each with sixty cuttings per replication in fiberglass house of Natural Jojoba Corporation at Yemen. The different rooting media used were peat moss + perlite + vermiculite (1:1:1), peat moss + perlite (1:1) and peat moss + sand (1:1). Plant materials used were semi-hard wood cuttings of jojoba plants with length of 15 cm. The cuttings were collected in the month of June during 2012 and 2013 from the sub-terminal growth of the mother plants of Amman farm and introduced to Yemen. They were wounded, treated with Indole butyric acid (IBA), α-naphthalene acetic acid (NAA) or Indole-3-acetic acid (IAA) all @ 4000 ppm (part per million) and cultured on different rooting media under intermittent mist propagation conditions. IBA gave significantly higher percentage of rooting (66.23%) compared to NAA and IAA in all media used. However, the lowest percentage of rooting (5.33%) was recorded with IAA in the medium consisting of peat moss and sand (1:1). No significant difference was observed at all types of PGRs used with rooting media in respect of root length. Maximum number of roots was noticed in medium consisting of peat moss, perlite and vermiculite (1:1:1); peat moss and perlite (1:1) and peat moss and sand (1:1) using IBA, NAA and IBA, respectively. The interaction among rooting media was statistically significant with respect to rooting percentage character. Similarly, the interactions among PGRs were significant in terms of rooting percentage and also root length characters. The results demonstrated suitability of propagation of jojoba plants by semi-hard wood cuttings.

Keywords: cutting, IBA, Jojoba, propagation, rhizogenesis

Procedia PDF Downloads 325

Authors: Rui Magalhães, Sohel Rana, Raul Fangueiro, Clara Gonçalves, Pedro Nunes, Gustavo Dias

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Auxetic fibrous structures and composites with negative Poisson’s ratio (NPR) have huge potential for application in ballistic protection due to their high energy absorption and excellent impact resistance. In the present research, re-entrant lozenge auxetic fibrous structures were produced through weft knitting technology using high performance polyamide and para-aramid fibres. Fabric structural parameters (e.g. loop length) and machine parameters (e.g. take down load) were varied in order to investigate their influence on the auxetic behaviours of the produced structures. These auxetic structures were then impregnated with two types of polymeric resins (epoxy and polyester) to produce composite materials, which were subsequently characterized for the auxetic behaviour. It was observed that the knitted fabrics produced using the polyamide yarns exhibited NPR over a wide deformation range, which was strongly dependant on the loop length and take down load. The polymeric composites produced from the auxetic fabrics also showed good auxetic property, which was superior in case of the polyester matrix. The experimental results suggested that these composites made from the auxetic fibrous structures can be properly designed to find potential use in the body amours for personal protection applications.

Keywords: auxetic fabrics, high performance, composites, energy absorption, impact resistance

Procedia PDF Downloads 234

Authors: Chia-Feng Lu, Yuh-Jen Wang, Shin Teng, Yu-Te Wu, Sui-Hing Yan

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Brain functional networks based on resting-state EEG data were compared between patients with mild Alzheimer’s disease (mAD) and matched patients with amnestic subtype of mild cognitive impairment (aMCI). We integrated the time–frequency cross mutual information (TFCMI) method to estimate the EEG functional connectivity between cortical regions and the network analysis based on graph theory to further investigate the alterations of functional networks in mAD compared with aMCI group. We aimed at investigating the changes of network integrity, local clustering, information processing efficiency, and fault tolerance in mAD brain networks for different frequency bands based on several topological properties, including degree, strength, clustering coefficient, shortest path length, and efficiency. Results showed that the disruptions of network integrity and reductions of network efficiency in mAD characterized by lower degree, decreased clustering coefficient, higher shortest path length, and reduced global and local efficiencies in the delta, theta, beta2, and gamma bands were evident. The significant changes in network organization can be used in assisting discrimination of mAD from aMCI in clinical.

Keywords: EEG, functional connectivity, graph theory, TFCMI

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Authors: Yuri Seu, Hyun Jin Park, Jin Seo Park, Yong-Suk Moon, HongtaeKim, Mi-Sun Hur

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The present case report describes bifid ureters arising directly from the separate calyces and renal pelvis of the kidney. It was a single common ureter leading away from the bladder, which was separated into incompletely duplicated ureters near the level of the anterior superior iliac supine. These two branches then entered the left kidney through their own courses. Each ureter traveled anterior and posterior to the renal vein, respectively. These two ureters formed a Y-shaped pattern. One ureter coursed anterior to the renal vein with shorter length, and it terminated at the renal pelvis that was divided into major calices in approximately lower two thirds of the kidney. The other ureter coursed posterior to the renal vein with longer length, terminating at approximately the upper third of the kidney. The renal calices in the upper third of the kidney were directly connected to the posterior ureter, whereas the other major calices in the lower two thirds of the kidney formed the renal pelvis connecting to the anterior ureter. Thus, convergence of the major calices was separated according to the terminations of two ureters. These anomalous ureters were traced to the calices of the kidney, thereby providing a reference of a rare variation of the ureter. The bifid ureters arising from the separate calyces and renal pelvis should be considered by radiologists when evaluating images and diagnosing possible complications of these anomalies.

Keywords: bifid ureters, kidney, major calices, renal pelvis

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Authors: Khater N., Rahmine S., Bougoffa C., Bouguenna T., Ouanes H.

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Moringa oleifera L. species is considered one of the most useful trees in the world, possessing many interesting properties that make it of great scientific interest. It has been described as the miracle tree, the tree of a thousand virtues, the tree of life and God's gift to man. The present study aims to introduce, produce, and develop Moringa Oleifera as a species with high ecological potential (resistance to biotic and abiotic stresses and productivity), high added value, and multiple virtues. The aim of this work is to study the germination potential of this species under different temperature conditions. In this study, the germination assay was tested in two different temperature ranges: internal (laboratory ambient temperature between 22°c and 25°c) and external (seasonal temperature between 4°c and 8°c). Morphological and physiological analyses were carried out by Shoot length (SL), root length (RL), diameter at the crown (DC), fresh weight of shoots (FWS), fresh weight of roots (FWR), dry weight of shoots (DWS) and dry weight of roots (DWS). For all these variables, the results of the study reveal a significant difference between the two temperature intervals, with a high germination rate of 81. 81% and plant growth was rapid (7cm during 24h) in the laboratory temperature; in contrast to the external temperatures, a germination rate value of around 27% was recorded, and germination took place after 20 days of sowing, with slower plant growth. The results obtained show that a temperature greater than or equal to 25° is the ideal temperature for the germination and growth of moringa seeds and has a positive influence on the speed and percentage of germination.

Keywords: moringa oleifera, temperature, germination rate, growth, biomass

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Authors: Yuan Wan, Shumei Cui, Shaopeng Wu

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Toroidal windings were taken advantage of to reduce of axial length of the motor, so as to match the applications that have severe restrictions on the axial length. But slotting in the out edge of the stator will decrease the heat-dissipation capacity of the water cooling of the housing. Besides, the windings in the outer slots will increase the copper loss, which will further increase the difficult for heat dissipation of the motor. At present, carbon-fiber composite retaining sleeve are increasingly used to be mounted over the magnets to ensure the rotor strength at high speeds. Due to the poor thermal conductivity of carbon-fiber sleeve, the cooling of the rotor becomes very difficult, which may result in the irreversible demagnetization of magnets for the excessively high temperature. So it is necessary to analyze the temperature rise of such motor. This paper builds a computational fluid dynamic (CFD) model of a toroidal-winding high-speed permanent magnet synchronous motor (PMSM) with water cooling of housing and forced air cooling of rotor. Thermal analysis was carried out based on the model and the factors that affects the temperature rise were investigated. Then thermal optimization for the prototype was achieved. Finally, a small-size prototype was manufactured and the thermal analysis results were verified.

Keywords: thermal analysis, temperature rise, toroidal windings, high-speed PMSM, CFD

Procedia PDF Downloads 475

Authors: Ali Akbar Heydari

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Control charts are an important tool of statistical quality control. Thesecharts are used to detect and eliminate unwanted special causes of variation that occurred during aperiod of time. The design and operation of control charts require the determination of three design parameters: the sample size (n), the sampling interval (h), and the width coefficient of control limits (k). Thevariable parameters (VP) x-bar controlchart is the x-barchart in which all the design parameters vary between twovalues. These values are a function of the most recent process information. In fact, in the VP x-bar chart, the position of each sample point on the chart establishes the size of the next sample and the timeof its sampling. The synthetic x-barcontrol chartwhich integrates the x-bar chart and the conforming run length (CRL) chart, provides significant improvement in terms of detection power over the basic x-bar chart for all levels of mean shifts. In this paper, we introduce the syntheticVP x-bar control chart for monitoring changes in the process mean. To determine the design parameters, we used a statistical design based on the minimum out of control average run length (ARL) criteria. The optimal chart parameters of the proposed chart are obtained using the Markov chain approach. A numerical example is also done to show the performance of the proposed chart and comparing it with the other control charts. The results show that our proposed syntheticVP x-bar controlchart perform better than the synthetic x-bar controlchart for all shift parameter values. Also, the syntheticVP x-bar controlchart perform better than the VP x-bar control chart for the moderate or large shift parameter values.

Keywords: control chart, markov chain approach, statistical design, synthetic, variable parameter

Procedia PDF Downloads 139

Authors: M. Mokhber, J. Hedayati

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From the managerial perspective, it is important to devise an operational plan based on top priorities due to limited resources, diversity of measures and high costs needed to improve safety in infrastructure. Dealing with the high-risk corridors across Iran, this study prioritized the corridors according to statistical data on accidents involving fatalities, injury or damage over three consecutive years. In collaboration with the Iranian Police Department, data were collected and modified. Then, the prioritization criteria were specified based on the expertise opinions and international standards. In this study, the prioritization criteria included accident severity and accident density. Finally, the criteria were standardized and weighted (equal weights) to score each high-risk corridor. The prioritization phase involved the scoring and weighting procedure. The high-risk corridors were divided into twelve groups out of 50. The results of data analysis for a three-year span suggested that the first three groups (150 corridors) along with a quarter of Iranian road network length account for nearly 60% of traffic accidents. In the next step, according to variables including weather conditions particular roads for the purpose of winter safety measures were extracted from the abovementioned categories. According to the results ranking, ‎‏9‏‎ roads with the overall ‎length of about ‎‎‏1000‏‎ Km of high-risk corridors are considered as preferences of ‎safety measures‎.

Keywords: high-risk corridors, HRCs, road safety rating, road scoring, winter safety measures

Procedia PDF Downloads 157

Authors: Viriyavudh Sim, SeungHyun Kim, JungKyu Choi, WooYoung Jung

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Glass Fiber Reinforced Polymer (GFRP) is a major evolution for energy dissipation when used as infill material for seismic retrofitting of steel frame, a basic PMC infill wall system consists of two GFRP laminates surrounding an infill of foam core. This paper presents numerical analysis in terms of buckling resistance of GFRP sandwich infill panels system under the influence of environment temperature and stacking sequence of laminate skin. Mode of failure under in-plane compression is studied by means of numerical analysis with ABAQUS platform. Parameters considered in this study are contact length between infill and frame, laminate stacking sequence of GFRP skin and variation of mechanical properties due to increment of temperature. The analysis is done with four cases of simple stacking sequence over a range of temperature. The result showed that both the effect of temperature and stacking sequence alter the performance of entire panel system. The rises of temperature resulted in the decrements of the panel’s strength. This is due to the polymeric nature of this material. Additionally, the contact length also displays the effect on the performance of infill panel. Furthermore, the laminate stiffness can be modified by orientation of laminate, which can increase the infill panel strength. Hence, optimal performance of the entire panel system can be obtained by comparing different cases of stacking sequence.

Keywords: buckling resistance, GFRP infill panel, stacking sequence, temperature dependent

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Authors: Shan Faiz, Arfat Anis, Saeed M. Al-Zarani

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High density polyethylene (HDPE) and poly benzimidazole fiber (PBI) composites were prepared by melt blending in a twin screw extruder (TSE). The thermo-mechanical properties of PBI fiber reinforced HDPE composite samples (1%, 4% and 8% fiber content) of fiber lengths 3 mm and 6 mm were investigated using differential scanning calorimeter (DSC), universal testing machine (UTM), rheometer and scanning electron microscopy (SEM). The effect of fiber content and fiber lengths on the thermo-mechanical properties of the HDPE-PBI composites was studied. The DSC analysis showed decrease in crystallinity of HDPE-PBI composites with the increase of fiber loading. Maximum decrease observed was 12% at 8% fiber length. The thermal stability was found to increase with the addition of fiber. T50% was notably increased to 40oC for both grades of HDPE using 8% of fiber content. The mechanical properties were not much affected by the increase in fiber content. The optimum value of tensile strength was achieved using 4% fiber content and slight increase of 9% in tensile strength was observed. No noticeable change was observed in flexural strength. In rheology study, the complex viscosities of HDPE-PBI composites were higher than the HDPE matrix and substantially increased with even minimum increase of PBI fiber loading i.e. 1%. We found that the addition of the PBI fiber resulted in a modest improvement in the thermal stability and mechanical properties of the prepared composites.

Keywords: PBI fiber, high density polyethylene, composites, melt blending

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Authors: Sara Lamari, Toufik Madani

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This study aimed to explore the relationship between reproduction performances and coat characteristics of Montbéliarde cows born in Algeria or imported from Europe during the hot season in Algeria. Hair coat traits (hair coat color, Hair Weight, hair length, the number of hair per unit area, total hair diameters and hair medulla diameters) were estimated in 18 imported cattle and 49 locally born cows. These traits were measured in an area of 20cm below the dorsal line in the center of the thorax. Results showed that hair coats were significantly different between locally born and imported cows. Imported cows had whiter coats when compared to locally born cows for Montbéliarde cows. A significant effect of total hair diameter was observed on the interval from calving to conception (IC) for imported Montbéliarde cows, suggesting less incidence of heat stress on reproduction efficiency of cows with thin diameter hair coats. Montbéliarde cows with short hair coat registered significantly more number of mating per conception (2, 28±1, 93 Vs. 1,67±0,92) and IC (98,04±78,81Vs 74.53 ± 35.60 days) when compared to cows with long hairs. Hair works as a temperature regulator in association with muscles in the skin and may affect reproduction performances during hit stress season. It can be assumed that the length and a total diameter of hairs for the Montbeliarde breed appears to be related to their reproductive efficiency.

Keywords: hair coat, reproduction, Montbeliarde cow, hot season

Procedia PDF Downloads 139

Authors: Yinggang Guo, Zongchun Li

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In order to decrease the accumulated survey error of tunnel installation control network of particle accelerator, a sectional control method is proposed. Firstly, the accumulation rule of positional error with the length of the control network is obtained by simulation calculation according to the shape of the tunnel installation-control-network. Then, the RMS of horizontal positional precision of tunnel backbone control network is taken as the threshold. When the accumulated error is bigger than the threshold, the tunnel installation control network should be divided into subsections reasonably. On each segment, the middle survey station is taken as the datum for independent adjustment calculation. Finally, by taking the backbone control points as faint datums, the weighted partial parameters adjustment is performed with the adjustment results of each segment and the coordinates of backbone control points. The subsections are jointed and unified into the global coordinate system in the adjustment process. An installation control network of the linac with a length of 1.6 km is simulated. The RMS of positional deviation of the proposed method is 2.583 mm, and the RMS of the difference of positional deviation between adjacent points reaches 0.035 mm. Experimental results show that the proposed sectional control method can not only effectively decrease the accumulated survey error but also guarantee the relative positional precision of the installation control network. So it can be applied in the data processing of tunnel installation control networks, especially for large particle accelerators.

Keywords: alignment, tunnel installation control network, accumulated survey error, sectional control method, datum

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Authors: Najafi S., Heidai R., Jamei R., Tofigh F.

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In order to study the effects of magnetic field on the root system and growth of Phaseolus vulgaris, an experiment was conducted in 2012. The possible involvement of magnetic field (MF) pretreatment in physiological factors of Phaseolus vulgaris was investigated. Seeds were subjected to 10 days with 1.8 mT of magnetic field for 1h per day. MF pretreatment decreased the plant height, fresh and dry weight, length of root and length of shoot, Chlorophyll a, Chlorophyll b and carotenoid in 10 days old seedling. In addition, activity of enzymes such as Catalase and Guaiacol peroxidase was decreased due to MF exposure. Also, the total Protein and DPPH content of the treated by magnetic field was not significantly changed in compare to control groups, while the flavonoid, Phenol and prolin content of the treated of the treated by magnetic field was significantly changed in compare to control groups. Lateral branches of roots and secondary roots increased with MF. The results suggest that pretreatment of this MF plays important roles in changes in crop productivity. In all cases there was observed a slight stimulating effect of the factors examined. The growth dynamics were weakened. The plants were shorter. Moreover, the effect of a magnetic field on the crop of Phaseolus vulgaris and its structure was small.

Keywords: carotenoid, Chlorophyll a, Chlorophyll b, DPPH, enzymes, flavonoid, germination, growth, phenol, proline, protein, magnetic field, phaseolus vulgaris

Procedia PDF Downloads 559

Authors: Hatem Shreha

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Aromatase inhibitors administered before sexual differentiation of the gonads can induce sex reversal in female chickens (phenotypic male). To analyze the process of sex reversal, we have followed for several months the changes induced by Fadrozole, a nonsteroidal aromatase inhibitor on the morphology of female sex-reversed and female sex-reversed supplemented with L-tyrosine which was previously shown to stimulate the release of Gn Rh. Fadrozole (1mg/egg) was injected into eggs on day four of incubation, phenotypic males and phenotypic males treated with L-tyrosine and males hatched from eggs injected Fadrozole were sacrificed by slaughtering at 16 weeks old and the remaining chicks were sacrificed at 28 weeks old. Both sexes from control chickens were sacrificed at the same age (16 &28 weeks). Hatchability, behavior, body weight, shank length, comb weight, testes weight, blood cells count and wattle weight of sex reversal were tested at 16 and 28 weeks. The results showed that body weight, comb weight, wattles weight and shank length of sex-reversed females were significantly different from control female. Behavior of phenotypic males and phenotypic males fed on L- tyrosine showed aggressive sexual behavior like that of control males and absence of laying behavior. In conclusion our results confirm that Fedrazole injection in eggs before sex differentiation produce a male behavior and morphological index of male in female chicken.

Keywords: sex reversal, fadrozole, phenotypic male, L- tyrosine

Procedia PDF Downloads 589

Authors: Sinwook Park, Gilad Yossifon

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The presence of a floating electrode array located within the depletion layer formed due to concentration-polarization (CP) across a microchannel-membrane device, produces not only induced-charge electro-osmosis (ICEO) vortex and but also a bipolar current resulting from faradaic reactions. It has been shown that there exists an optimal SiO2 layer thickness of ~50nm which is sufficient to suppress bipolar currents (at least up to 5V applied voltage) but still enables ICEO vortices that stir the depletion layer, thereby affecting its I-V response. This effect is pronounced beyond the limiting current where the existence of the depletion layer results in increased local electric field due to decreased solution conductivity. This comprehensive study of the interaction of embedded electrodes with the induced CP in microchannel-perm selective medium systems, allows one to choose the thickness of the thin dielectric coating to either enhance the mixing as a means to control the diffuse layer, or suppress it, for example, in the case where electrodes are intended for local measurements of the solution conductivity with minimal invasion. In addition, the use of alternating-current electro-osmosis by activating electrodes results in further enhancement of the fluid stirring and opens new routes for on-demand spatiotemporal control of the CP length. In addition, the use of embedded heaters within the depletion layer generates electro-thermal vortices that in turn also control the CP length.

Keywords: AC electrokinetics, microchannel, concentration-polarization, bipolar current

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Authors: Prataksitorn Chonlakan, Tiparat Wongsilarat

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The traditional clinical practice guideline used at the emergency room at Songkhla Hospital in caring for patients who come in contact with jellyfish venom took a long time for the pain to reduce to the level that patients can cope with. To investigate the effectiveness of clinical practice guidelines by comparing the effectiveness of a newly developed clinical practice guideline with the traditional clinical practice guideline in the following aspects: 1) pain reduction, 2) length of pain, 3) the rate of patient’s re-visit, 4) the rate of severe complications such as anaphylactic shock, and cardiac arrest, and death, and 5) patient satisfaction. This study employed a quasi-experimental research design. Thirty subjects were selected with purposive sampling from jellyfish-sting patients who came for treatment at the Emergency Room of Songkhla Hospital. The subjects were divided using random assignment into two groups of 15 each: an experimental group, and the control group. The control group was treated using the traditional clinical practice guideline consisting of rinsing the affected area with 0.9% normal saline, using a cloth soaked with vinegar to press against the affected area, and controlling pain using tramadol or diclofenac intramuscular injection. The data were analyzed using descriptive statistics and paired t-test at the significance level p < 0.05. The results of the study revealed the following. The pain level in the experimental group was significantly lower than that of the control group (the average pain score of the experimental group was 3.46 while that of the control group was 6.33) (p < 0.05).The length of pain in the experimental group was significantly lower than that of the control group (the average length of pain in the experimental group was 48.67 minutes while that of the control group was 105.35 minutes) (p < 0.05). The rate of re-visit within 12 hours in the experimental group was significantly lower than that of the control group (the rate of re-visit within 12 hours of the experimental group was 0.07 while that of the control group was 0.00) (p < 0.05).No severe complications such as anaphylactic shock, and cardiac arrest were found in the two groups of subjects.The rate of satisfaction among the subjects in the experimental group was significantly higher than that of the control group (the rate of satisfaction among the subjects of the experimental group was 90.00 percent while that among the control group was 66.33 percent) (p < 0.05). The newly develop clinical practice guideline could reduce pain and increase satisfaction among jellyfish-sting patients better than the traditional clinical practice guideline.

Keywords: effectiveness, clinical practice guideline, jellyfish-sting patients, cardiac arrest

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Authors: Choon Seong Ng, P. Petrick, C. L. Lau

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Background: Carbapenem-resistant isolates have been increasingly reported recently. Carbapenem stewardship is designed to optimize its usage particularly among medical wards with high prevalence of carbapenem prescriptions to combat such emerging resistance. Carbapenem stewardship programmes (CSP) can reduce antibiotic use but clinical outcome of such measures needs further evaluation. We examined this in a prospective manner using feedback mechanism. Methods: Our single-center prospective cohort study involved all carbapenem prescriptions across the medical wards (including medical patients admitted to intensive care unit) in a tertiary university hospital setting. The impact of such stewardship was analysed according to the accepted and the rejected groups. The primary endpoint was safety. Safety measure applied in this study was the death at 1 month. Secondary endpoints included length of hospitalisation and readmission. Results: Over the 19 months’ period, input from 144 carbapenem prescriptions was analysed on the basis of acceptance of our CSP recommendations on the use of carbapenems. Recommendations made were as follows : de-escalation of carbapenem; stopping the carbapenem; use for a short duration of 5-7 days; required prolonged duration in the case of carbapenem-sensitive Extended Spectrum Beta-Lactamases bacteremia; dose adjustment; and surgical intervention for removal of septic foci. De-escalation, shorten duration of carbapenem and carbapenem cessation comprised 79% of the recommendations. Acceptance rate was 57%. Those who accepted CSP recommendations had no increase in mortality (p = 0.92), had a shorter length of hospital stay (LOS) and had cost-saving. Infection-related deaths were found to be higher among those in the rejected group. Moreover, three rejected cases (6%) among all non-indicated cases (n = 50) were found to have developed carbapenem-resistant isolates. Lastly, Pitt’s bacteremia score appeared to be a key element affecting the carbapenem prescription’s behaviour in this trial. Conclusions: Carbapenem stewardship program in the medical wards not only saves money, but most importantly it is safe and does not harm the patients with added benefits of reducing the length of hospital stay. However, more time is needed to engage the primary clinical teams by formal clinical presentation and immediate personal feedback by senior Infectious Disease (ID) personnel to increase its acceptance.

Keywords: audit and feedback, carbapenem stewardship, medical wards, university hospital

Procedia PDF Downloads 190

Authors: Edmar N. Franquera, Renato C. Mabesa, Rene Rafael C. Espino, Edralina P. Serrano, Eduardo P. Paningbatan Jr.

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The potential of growing lettuce with different colored plastic mulch silver (control), red, orange, yellow and green was evaluated using two lettuce varieties, Looseleaf and Romaine. The experiment was laid out on split plot design following the Randomized Complete Block Design. The Looseleaf variety had better performance in terms of plant fresh weight, leaf fresh weight, leaf dry weight, root length, plant height and yield. However, better response was observed in Romaine in terms of leaf diameter, leaf length, root dry weight and root fresh weight. The color of the mulch reflected different qualities of light and hence the quality of absorbed light by the lettuce plants. A higher Far red and red ratio (FR:R) was obtained from green plastic mulch which was followed by the red plastic mulch. The different colored plastic mulch affected the growth and developmental responses of leaf lettuce morphological and leaf anatomical characteristics. Data in all growth morphological and yield parameters showed that those grown with red plastic mulch had better response and had longer stomates than those lettuce grown with the other colored plastic mulch. The soil temperature 10 cm below the plastic mulch was significantly influenced by the color of the mulch. The red plastic mulch had the highest soil temperature recorded while the lowest soil temperature recorded was within the yellow plastic mulch.

Keywords: anatomical, lettuce, morpholological, plastic mulch

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Authors: Jakub Marek, Marie Vagnerova, Ladislav Csemy

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Background: The length of time spent on the street influences the degree of adjustment to homelessness. Over the years spent sleeping rough, homeless people gradually lose the ability to control their lives and their return to mainstream society becomes less and less likely. Goals: The aim of the study was to discover whether and how men who have been sleeping rough for more than ten years differ from those who have been homeless for four years or less. Methods: The research was based on a narrative analysis of in-depth interviews focused on the respondent’s entire life story, i.e. their childhood, adolescence, and the period of adulthood preceding homelessness. It also asked the respondents about how they envisaged the future. The group under examination comprised 51 homeless men aged 37 – 54. The first subgroup contained 29 men who have been sleeping rough for 10 – 21 years, the second group contained 22 men who have been homeless for four years or less. Results: Men who have been sleeping rough for more than ten years had problems adapting as children. They grew up in a problematic family or in an institution and acquired only a rudimentary education. From the start they had problems at work, found it difficult to apply themselves, and found it difficult to hold down a job. They tend to have high-risk personality traits and often a personality disorder. Early in life they had problems with alcohol or drugs and their relationships were unsuccessful. If they have children, they do not look after them. They are reckless even in respect of the law and often commit crime. They usually ended up on the street in their thirties. Most of this subgroup of homeless people lack motivation and the will to make any fundamental change to their lives. They identify with the homeless community and have no other contacts. Men who have been sleeping rough for four years or less form two subgroups. There are those who had a normal childhood, attended school and found work. They started a family but began to drink, and as a consequence lost their family and their job. Such men end up on the street between the ages of 35 and 40. And then there are men who become homeless after the age of 40 because of an inability to cope with a difficult situation, e.g. divorce or indebtedness. They are not substance abusers and do not have a criminal record. Such people can be offered effective assistance to return to mainstream society by the social services because they have not yet fully self-identified with the homeless community and most of them have retained the necessary abilities and skills. Conclusion: The length of time a person has been homeless is an important factor in respect of social prevention. It is clear that the longer a person is homeless, the worse are their chances of being reintegrated into mainstream society.

Keywords: risk factors, homelessness, chronicity, narrative analysis

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Authors: Erjola Reufi, Thomas Beer

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Plain, unreinforced concrete is a brittle material, with a low tensile strength, limited ductility and little resistance to cracking. In order to improve the inherent tensile strength of concrete there is a need of multi directional and closely spaced reinforcement, which can be provided in the form of randomly distributed fibers. Fiber reinforced concrete (FRC) is a composite material consisting of cement, sand, coarse aggregate, water and fibers. In this composite material, short discrete fibers are randomly distributed throughout the concrete mass. The behavioral efficiency of this composite material is far superior to that of plain concrete and many other construction materials of equal cost. The present experimental study considers the effect of steel fibers and polypropylene fiber on the modulus of elasticity of concrete. Hook end steel fibers of length 5 cm and 3 cm at volume fraction of 0.25%, 0.5% and 1.% were used. Also polypropylene fiber of length 12, 6, 3 mm at volume fraction 0.1, 0.25, and 0.4 % were used. Fifteen mixtures has been prepared to evaluate the effect of fiber on modulus of elasticity of concrete. Ultrasonic pulse velocity (UPV) and resonant frequency methods which are two non-destructive testing techniques have been used to measure the elastic properties of fiber reinforced concrete. This study found that ultrasonic wave propagation is the most reliable, easy and cost effective testing technique to use in the determination of the elastic properties of the FRC mix used in this study.

Keywords: fiber reinforced concrete(FRC), polypropylene fiber, resonance, ultrasonic pulse velocity, steel fiber

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Authors: Satpal Yadav, Biswajit Basumatary, Arvind S. Sajwan, Ranjan Chakravarty

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The purpose of the study was to assess the effect of 2D kinematical selected variables on sprint start with sprinting performance of novice athletes. Six (3 National and 3 State level) athletes of sports authority of India, Guwahati has been selected for this study. The mean (M) and standard deviation (SD) of sprinters were age (17.44, 1.55), height (1.74m, .84m), weight (62.25 kg, 4.55), arm length (65.00 cm, 3.72) and leg length (96.35 cm, 2.71). Biokin-2D motion analysis system V4.5 can be used for acquiring two-dimensional kinematical data/variables on sprint start with Sprinting Performance. For the purpose of kinematic analysis a standard motion driven camera which frequency of the camera was 60 frame/ second i.e. handy camera of Sony Company were used. The sequence of photographic was taken under controlled condition. The distance of the camera from the athletes was 12 mts away and was fixed at 1.2-meter height. The result was found that National and State level athletes significant difference in there, trajectory knee, trajectory ankle, displacement knee, displacement ankle, linear velocity knee, linear velocity ankle, and linear acceleration ankle whereas insignificant difference was found between National and State level athletes in their linear acceleration knee joint on sprint start with sprinting performance. For all the Statistical test the level of significance was set at p<0.05.

Keywords: 2D kinematic analysis, sprinting performance, novice athletes, sprint start

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Authors: Ali Mardani-Aghabaglou, Zia Ahmad Faqiri, Semsi Yazici

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In this study, the effect of permeability reducing admixture (PRA) utilization on fresh properties, compressive strength and sulfate resistance of self-consolidating concrete (SSC) were investigated. For this aim, two different commercial PRA were used at two utilization ratios as %0.1 and %0.2 wt. CEM I 42.5 R type cement and crushed limestone aggregate having Dmax of 15 mm were used for preparing of SCC mixtures. In all mixtures, cement content, water/cement ratio, and flow value were kept constant as 450 kg, 0.40 and 65 ± 2 cm, respectively. In order to obtain desired flow value, a polycarboxylate ether-based high range water reducing admixture was used at different content. T50 flow time, flow value, L-box, and U-funnel of SCC mixture were measured as fresh properties. 1, 3, 7 and 28-day compressive strength of SCC mixture were obtained on 150 mm cubic specimens. To investigate the sulfate resistance of SCC mixture 75x75x285 mm prismatic specimens were produced. After 28-day water curing, specimens were immersed in %5 sodium sulfate solution during 210 days. The length change of specimens was measured at 5-day time intervals up to 210 days. According to the test results, all fresh properties of SCC mixtures were in accordance with the European federation of specialist construction chemicals and concrete systems (EFNARC) critter for SCC mixtures. The utilization of PRA had no significant effect on compressive strength and fresh properties of SCC mixtures. Regardless of PRA type, sulfate resistance of SCC mixture increased by adding of PRA into the SCC mixtures. The length changes of the SCC mixtures containing %1 and %2 PRA were measured as %8 and %14 less than that of control mixture containing no PRA, respectively.

Keywords: permeability reducing admixture, self-consolidating concrete, fresh properties, sulfate resistance

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Authors: Chaiyawat Musikapan, Ratchatin Chancharoen, Saknan Bongsebandhu-Phubhakdi

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For many recent years, soft robotic fingers were used for supporting the patients who had survived the neurological diseases that resulted in muscular disorders and neural network damages, such as stroke and Parkinson’s disease, and inflammatory symptoms such as De Quervain and trigger finger. Generally, the major hand function is significant to manipulate objects in activities of daily living (ADL). In this work, we proposed the model of soft actuator that manufactured by full 3D printing without the molding process and one material for use. Furthermore, we designed the model with a technique of multi cavitation cells (MC-Cells). Then, we demonstrated the curvature bending, fluidic pressure and force that generated to the model for assistive finger flexor and hand grasping. Also, the soft actuators were characterized in mathematics solving by the length of chord and arc length. In addition, we used an adaptive push-button switch machine to measure the force in our experiment. Consequently, we evaluated biomechanics efficiency by the range of motion (ROM) that affected to metacarpophalangeal joint (MCP), proximal interphalangeal joint (PIP) and distal interphalangeal joint (DIP). Finally, the model achieved to exhibit the corresponding fluidic pressure with force and ROM to assist the finger flexor and hand grasping.

Keywords: biomechanics efficiency, curvature bending, hand functional assistance, multi cavitation cells (MC-Cells), range of motion (ROM)

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Authors: Maletsema Alina Mofokeng, Nemera Shargie

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Sorghum is one of the most important cereal crops grown as a source of calories for many people in tropics and sub-tropics of the world. Proper characterisation and evaluation of crop germplasm is an important component for effective management of genetic resources and their utilisation in the improvement of the crop through plant breeding. The objective of the study was to estimate the genetic diversity present in sorghum accessions grown in South Africa using agro-morphological traits and some nutritional contents. The experiment was carried out in Potchefstroom. Data were subjected to correlations, principal components analysis, and hierarchical clustering using GenStat statistical software. There were highly significance differences among the accessions based on agro-morphological and nutritional quality traits. Grain yield was highly positively correlated with panicle weight. Plant height was highly significantly correlated with internode length, leaf length, leaf number, stem diameter, the number of nodes and starch content. The Principal component analysis revealed three most important PCs with a total variation of 78.6%. The protein content ranged from 7.7 to 14.7%, and starch ranged from 58.52 to 80.44%. The accessions that had high protein and starch content were AS16cyc and MP4277. There was vast genetic diversity observed among the accessions assessed that can be used by plant breeders to improve yield and nutritional traits.

Keywords: accessions, genetic diversity, nutritional quality, sorghum

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Authors: Farzad Tofigh, Saeideh Najafi, Reza Heidari, Rashid Jamei

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In order to study the effects of magnetic field on the root system and growth of Phaseolus vulgaris, an experiment was conducted in 2012. The possible involvement of magnetic field (MF) pretreatment in physiological factors of Phaseolus vulgaris was investigated. Seeds were subjected to 10 days with 1.8 mT of magnetic field for 1h per day. MF pretreatment decreased the plant height, fresh and dry weight, length of root and length of shoot, Chlorophyll a, Chlorophyll b and carotenoid in 10 days old seedling. In addition, activity of enzymes such as Catalase and Guaiacol peroxidase was decreased due to MF exposure. Also, the total Protein and DPPH content of the treated by magnetic field was not significantly changed in compare to control groups, while the flavonoid, Phenol and prolin content of the treated of the treated by magnetic field was significantly changed in compare to control groups. Lateral branches of roots and secondary roots increased with MF. The results suggest that pretreatment of this MF plays important roles in changes in crop productivity. In all cases there was observed a slight stimulating effect of the factors examined. The growth dynamics were weakened. The plants were shorter. Moreover, the effect of a magnetic field on the crop of Phaseolus vulgaris and its structure was small.

Keywords: carotenoid, chlorophyll a, chlorophyll b, DPPH, enzymes, flavonoid, germination, growth, phenol, proline, protein, magnetic field

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Authors: Esam I. Jassim

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The main aim of this paper is to demonstrate the prediction of the model capability of predicting the nucleation process, the growth rate, and the deposition potential of second phase particles in gas flowlines. The primary objective of the research is to predict the risk hazards involved in the marine transportation of compressed natural gas. However, the proposed model can be equally used for other applications including production and transportation of natural gas in any high-pressure flow-line. The proposed model employs the following three main components to approach the problem: computational fluid dynamics (CFD) technique is used to configure the flow field; the nucleation model is developed and incorporated in the simulation to predict the incipient hydrate particles size and growth rate; and the deposition of the gas/particle flow is proposed using the concept of the particle deposition velocity. These components are integrated in a comprehended model to locate the hydrate deposition in natural gas flowlines. The present research is prepared to foresee the deposition location of solid particles that could occur in a real application in Compressed Natural Gas loading and offloading. A pipeline with 120 m length and different sizes carried a natural gas is taken in the study. The location of particle deposition formed as a result of restriction is determined based on the procedure mentioned earlier and the effect of water content and downstream pressure is studied. The critical flow speed that prevents such particle to accumulate in the certain pipe length is also addressed.

Keywords: hydrate deposition, compressed natural gas, marine transportation, oceanography

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Authors: Sung-Hee Nam, Kwang-Gill Lee, You-Young Jo, HaeYong Kweon

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Entomopathogenic fungi is a Cordyceps species that is isolated from dead silkworm and cicada. Fungi on cicadas were described in old Chinese medicinal books and From ancient times, vegetable wasps and plant worms were widely known to have active substance and have been studied for pharmacological use. Among many fungi belonging to the genus Cordyceps, Cordyceps sinensis have been demonstrated to yield natural products possessing various biological activities and many bioactive components. Generally, It is commonly used to replenish the kidney and soothe the lung, and for the treatment of fatigue. Due to their commercial and economic importance, the demand for Cordyceps has been rapidly increased. However, a supply of Cordyceps specimen could not meet the increasing demand because of their sole dependence on field collection and habitat destruction. Because it is difficult to obtain many insect hosts in nature and the edibility of host insect needs to be verified in a pharmacological aspect. Recently, this setback was overcome that P. tenuipes was able to be cultivated in a large scale using silkworm as host. Pharmacological effects of P. tenuipes cultured on silkworm such as strengthening immune function, anti-fatigue, anti-tumor activity and controlling liver etc have been proved. They are widely commercialized. In this study, we attempted to establish a method for stable growth inhibition of P. tenuipes on silkworm hosts and an optimal condition for synnemata formation. To determine optimum culturing conditions, temperature and light conditions were varied. The length and number of synnemata was highest at 25℃ temperature and 100~300 lux illumination. On an average, the synnemata of wild P. tenuipes measures 70 ㎜ in length and 20 in number; those of the cultured strain were relatively shorter and more in number. The number of synnemata may have increased as a result of inoculating the host with highly concentrated conidia, while the length may have decreased due to limited nutrition per individual. It is not able that changes in light illumination cause morphological variations in the synnemata. However, regulation of only light and temperature could not produce stromata like perithecia, asci, and ascospores. Yamanaka reported that although a complete fruiting body can be produced under optimal culture conditions, it should be regarded as synnemata because it does not develop into an ascoma bearing ascospores.

Keywords: paecilomyces tenuipes, entomopathogenic fungi, silkworm larva, bombyx mori

Procedia PDF Downloads 305