bluuebunny/crossref_metadata_2025 huggingface dataset:
Indirect Selective Laser Sintering of 316L Powder and the Properties of the Parts
Authors: Ren Nai Fei , Hang Ya Hui , Zhao Yan , Yang Qi Yu
Published: July 2015

During selective laser sintering process, different sintering parameters have great impact on the performance of the molded parts, and the degree of influence is different. Using orthogonal test, indirect sintered 316L stainless steel, the compressive strength and precision of the parts were measured and compared to study the influence of various sintering parameters (laser power, scanning speed, scan spacing, preheating temperature) on sintering. The greater degree of influence factors were got by range analysis. The results show that laser power, scanning speed and scan spacing have greater degree of influence on the compressive strength of the parts, and the preheating temperature have less impact. By comparison, the optimum set of parameters was concluded: the laser power is 15W, the scanning speed is 1900mm/s, the scan spacing is 0.125mm, and the preheating temperature is 60°C.
Numerical Simulation for the Multi-Point Incremental Forming Process
Authors: Yang Wan Mian , Luo Yuan Xin , Liu Zhi Fang , Du Ru Xu
Published: July 2015

Multi-point forming process has been developed to shape the sheet metal with bidirectional curvature. However, the forming force usually climbs too high so that the dimension of the forming machine should be designed to meet it. To solve this problem, the multi-point incremental forming (MPIF) process was proposed in this paper. First, the principle of this new forming process was introduced. Then, the experimental device was designed. Next, the MPIF process was simulated by a finite element model. The forming effects including displacements, thickness, and curvatures were visualized and discussed in detail. It was found that there is no obvious thickness change during the forming process. The advantage of this forming process is that the shape of the sheet metals adaptable and controllable with small forming force.
Comparative Analysis of Three Kinds of Mega Steel Frame System Static Performance
Authors: Yang Si Qi , Cai Jun Hua , Chen Jia , Tang Bai Jian
Published: July 2015

Mega steel structure because of its own advantages is widely used in high-rise buildings, especially in super high-rise buildings. Mega frame structure, mega steel frame-prestressed composite bracing structure and mega steel frame-cable bracing structure were analyzed in this paper. The structure deformation and internal force of beam and column of structures were studied under load combination of Pretension and vertical loads, horizontal wind load. The results show that prestressed cable can improve the system stiffness, make the overall stiffness more uniform and control the deflection of mega beam and axial force of mega column effectively.
Online Dynamic Compensation of Pressure Sensor
Authors: Zhang Jun Xiang , Ge Kun Shan , Gao Zhan Bao , Dong Shao Peng
Published: July 2015

An online dynamic compensation of the pressure sensor based on simultaneous identification method of model order and parameter is proposed to identify the model of pressure sensor and set digital compensation links for the pressure sensor. While simulating, the compensation links can broaden the frequency band and improve the dynamic process of the pressure sensor. This article describes the realization of the digital dynamic compensation with DSP processor and the process of the experimental verification. The results show that the simultaneous identification method can be used in determination of model and digital compensation links for pressure sensor effectively. And DSP measurement device can complete online dynamic compensation effectively.
Design and Implementation of the Clamping Device for the Underwater Blast Shoveling
Authors: Zhang Hui
Published: July 2015

In order to improve underwater blast shoveling reliability, a new device, namely the clamping device with locking function for underwater hydraulic impulsion shovel, was proposed in this paper. First of all, according to the principle of underwater hydraulic impulsion shovel, the existed structures and features of the clamping device are analyzed. Secondly, the clamping device with locking function is presented under used conditions. The design and calculation of the clamping device are presented. Finally, the clamping device model is established based on ergonomic design principles of the clamping device, which proves that the method is feasible and effective.
Thermal Resistance of Perforated Heat Sinks with Circular Pin Fins Cooled by Natural Convection
Authors: Wen Mao Yu , Yeh Cheng Hsiung
Published: July 2015

This study examines thermal resistance under natural convection for two different types (Type A and Type B) of pin-fin heat sinks with/without a hollow in the heated base. The effects of the rate of heat transfer, the height of fin, the finning factor, the heat sink porosity and the perforated base plate on the thermal resistance were investigated and evaluated. Experimental results show that thermal resistance, using pin-fin heat sinks, is significantly different for Type A and Type B.
Development of an Adaptive KIT for Wheelchair Turning it into an Electric Tricycle
Authors: Cunha Rodrigo Bruck , Goulart Mendes Marra Gabriel , Brito Pedro Paiva , Santos Vimieiro Claysson Bruno
Published: July 2015

The wheelchair is one of the most used equipment for moving people with motion deficit in the lower limbs. The objective of this work was to design a KIT adaptable to a conventional wheelchair, turning it into an electric tricycle, in order to facilitate the movement of wheelchair users. This KIT enables the adaptive wheelchair travel greater distances in less time, making more quality of life. A structure was designed to fit in a conventional wheelchair, with the aid of CAD tools. This structure is sized to be able to withstand the stresses to which it is submitted. The adaptive KIT presented in this work can be used in a wide variety of models of wheelchairs and is functional, safe, and economically viable.
Microstructural Design of an AlMgSi Alloy via ECAP Processing: An Advanced SPD Manufacturing Technique for NC/UFG Materials
Authors: Serban Nicolae , Răducanu Doina , Cojocaru Vasile Danut , Ghiban Nicolae
Published: July 2015

Severe plastic deformation (SPD) has received enormous interest over the last two decades as a method capable of producing fully dense and bulk ultra-fine grained (UFG) and nanocrystalline (NC) materials. Significant grain refinement obtained by SPD leads to improvement of mechanical, microstructural and physical properties. Compared to classical deformation processes, the big advantage of SPD manufacturing techniques, represented in particular by equal channel angular pressing (ECAP) is the lack of shape-change deformation and the consequent possibility to impart extremely large strain. In ECAP processing, the workpiece is pressed through a die in which two channels of equal cross-section intersect at an angle of ϕ and an additional angle of ψ define the arc of curvature at the outer point of intersection of the two channels. As a result of pressing, the sample theoretically deforms by simple shear and retains the same cross-sectional area to allow repeated pressings for several cycles. A commercial AlMgSi alloy was investigated in our study. The specimens were processed at room temperature for multiple passes, using three different ECAP dies. All samples (ECAP processed and as-received) were subjected to metallographic analysis and mechanical testing. Several correlations between the main processing parameters and the resulting microstructural aspect and mechanical features for the processed material were established. It was shown that severe plastic deformation by means of ECAP processing can be used in aluminum alloys microstructural design as an advanced tool for grain refinement in order to attain the desired microstructure and mechanical properties.
Die Failures in Copper Hot Extrusion
Authors: Schwartz Michal , Gheorghe Dan , Ciocoiu Robert , Ciucă Ion
Published: July 2015

Low life service of steel dies used in copper extrusion brought us to inspect several discarded copper hot extrusion dies in order to identify failures and failure mechanisms. The investigations performed are mainly hardness tests and microscopic investigations. The profiles extruded are circular, rectangular and hexagonal. It was observed that die design is not at fault; rather the die material is to blame for low life service of the tool. Discarded extrusion dies after copper hot extrusions were investigated. The failure of the dies was first observed by naked eye and the observations recorded. From the dies the ones with most plastic deformations and obvious signs of failure were selected. An improvement in die design could expand the service life, but our main concern is the material: a balance between toughness and hot strength is critical, yet this balance is hard to achieve. Other thermal processing of the die is still in question and investigations are currently being performed. At least an increase of tool service life could be achieved by thermal processing of the material to a state prior nanometric carbide precipitation between martensitic plates.
Al/Al2O3+Gr Hybrid Composite Compacting Behavior
Authors: Matara Mihaița Adrian , Csáki Ioana , Lucaci Mariana , Lungu Magdalena , Popescu Gabriela , Iacob Gheorghe
Published: July 2015

The researches have been focused on composite materials area, especially hybrid metal matrix composites. A hybrid composite has two or more reinforcing elements and improved properties according to the reinforcing elements used.This paper aims to discuss the Al/Al2O3+Grp behavior at different pressing forces. The composite was processed by a powder metallurgy route. Alumina used as reinforcing material provides a high strength and hardness and graphite provides lubricating properties. The results show that the compressed un-granulated powder has a higher tendency to fracture than the granulated powder. The compressed powder density was almost constant after a pressing force of 600 MPa.
Mechanical Behavior for some Cobalt Alloys
Authors: Ghiban Alexandru , Ghiban Brandusa , Borţun Cristina Maria , Serban Nicolae , Buzatu Mihai
Published: July 2015

Four compositions of some usually commercial dental alloys were investigated in order to determine the mechanical characteristics and fractographic analysis of tensile and bending tests surfaces. A correlation between chemical composition (either molybdenum or molybdenum and chromium contents) and mechanical characteristics (longitudinal modulus, tensile strength and elongation) were finally done.
Finite Element Modeling of Clinching Process for Joining Dissimilar Materials
Authors: Eshteyah M. , Hrairi Meftah , Dawood M.S. , Mohiuddin A.K.M.
Published: July 2015

Clinching is one of the important new joining techniques, in which two plate metal parts are locally plastically deformed by mechanical interlock. Clinching is a mechanical joining method by using simple tools that consist of a punch, a die, and a blank-holder. The shapes of these tools are the most important parameters that control the final geometry of the clinch joints which in turn strongly affect the strength and quality of the final joint. In this study, finite element simulations are carried out to investigate some of the difficulties regarding the optimization of the process parameters, and major expected geometric parameters that will influence the strength, joinability, and the quality of the joint.
Effect of Calcium Carbonate Replacement on Workability and Mechanical Strength of Portland Cement Concrete
Authors: Ali Maisarah , Abdullah Muhd Sufian , Saad Siti Asmahani
Published: July 2015

The continued growth of the world construction sectors has resulted in high demand for concrete materials. The innovation of using filler as a replacement for cement is becoming a trend in order to reduce the cement consumption and provide benefit in various ways. Hence forth, 10% of cement was replaced by the calcium carbonate (CaCO3) in this study. CaCO3 is a natural material, which has a finer particles size as compared to the cement particles. This improves particle packing of concrete and give spacer effect. The concrete with CaCO3 replacement possess a higher slump, which increased the workability. The specimens were prepared in 150mm x 150mm x 150mm mould. At 28 days, the water absorbed by hardened concrete was lower for CaCO3 as microscopy analysis indicates very low porosity in CaCO3 concrete. Mechanical properties tests were conducted in 3, 7 and 28 days. The CaCO3 helps to increase the early strength, due to the accelerator effect and high rate of hydration which hardens the concrete quicker. At matured age, the concrete with the CaCO3 addition exhibits lower strength as compared with concrete without CaCO3, but still within the target strength.
Effect of Sintering Schedule to the Alloyability of FeCrAl Powder Mix Formed at above Ambient Temperature
Authors: Rahman Mujibur M. , Talib A.A.A.
Published: July 2015

This paper presents the outcomes of an experimental investigation on the effect of sintering schedule to the alloyability of FeCrAl powder mix formed through warm powder compaction process. A lab-scale uni-axial die compaction rig was designed and fabricated which enabled the compaction of powder mass at elevated temperature. Iron (Fe) powder ASC 100.29 was mechanically mixed with other alloying elements, namely chromium (Cr), and aluminum (Al) for 60 minutes and compacted at 150°C by applying 130 kN axial loading to generate green compacts. The defect-free green compacts were subsequently sintered in an argon gas fired furnace for different holding times. The sintered samples were then undergone XRD analysis. The results revealed that the alloyability of sintered products were affected by the holding time during sintering. The sample sintered at 800°C for 60 minutes showed the highest intensity of FeCrAl alloy.
Effects of Surfactant on Corrosion Behavior of Carbon Steel in Simulated Crude Oil
Authors: Zakaria Mohammad , Suryanto  , Hilmy Irfan
Published: July 2015

Enhanced Oil Recovery (EOR) is a technique used in oil and gas industries to increase the amount of crude oil production by injection of brine, a mixture of surfactant, water and seawater. As the results, crude oil contains brine which is corrosive. Surfactant is used to lessen the corrosion effect in addition to increase flowing of oil. In this study, the effect of surfactant on corrosion behavior of carbon steel in simulated enhanced oil recovery crude was investigated. Autoclave machine was used to perform corrosion experiment in the oxygen free environments. Corrosion rate was measure using weight loss method. The results show that surfactant reduces corrosion rate of carbon steel from 0.061 mm/y to 0.042 mm/y and the corrosion type on carbon steel was uniform corrosion.
Surface Quality Produced in EDM with Tungsten Carbide and Copper Compacted Electrodes
Authors: Ali Khan Ahsan , Baba Ndaliman Mohammed , binti Mohamad Ummu Atiqah Khairiyah , binti Sulong Nurul Farhana , Mohd Zain Zakaria
Published: July 2015

Electrical discharge machining (EDM) is one of the most commonly used technique to machine very hard materials. Materials like hardened tool steels, titanium and its alloys and difficult-to-machine materials can be easily processed with EDM. The machining performance to a great extent depends on the composition of the electrode. This paper presents the machining performance of powder metallurgy (PM) compacted electrodes made from titanium carbide (TiC) and copper (Cu) powders. The Cu-TiC electrodes made up of 70% of TiC and 30% of Cu powders. They were compacted at a pressure of 6,000 psi (41.34 MPa). Mild steel was used as the workpiece material. Machining was conducted with the peak current, pulse-on time and pulse-off time as the electrical input variables. The output variables of the investigation were work surface roughness and its hardness. It was found that work surface roughness increases with increase in current and pulse-on-time. However, it decreases with increase in pulse-off time. It was found that the highest value of surface roughness (14.782 μm) was found at highest peak current (6.5 A), highest pulse on-time (7.5 μs) and lowest pulse-off time (6.5 μs). The highest value of surface hardness (57.3 BHB) was found at the same machining conditions. The smoothest surface (14.782 μm) was found at the lowest peak current (3.5 A), lowest pulse on-time (6.0 μs) and highest pulse-off time (8.5 μs). The lowest value of surface hardness (42.9 BHB) was found at the same machining conditions.
Corrosion of Surface Modified AISI 4340 Steel in Jatropha Biodiesel
Authors: Maleque Md Abdul , Ghazal B.A. , Ali Mohammad Yeakub , Hayyan M. , Saleh A.A.
Published: July 2015

The aim of this paper is to study the effect of jatropha curcas biodiesel on the corrosion behavior of surface modified low alloy steel after modification by TIG torch surface melting technique. The coating layer was produced by preplacement of 1 mg/mm2 TiC particulate into the surface of AISI 4340 steel and at heat input of 1344 J/mm using an electric arc generated from the tungsten electrode that melt the powder with substrate material to form a composite layer. The micrograph of the composite coated surface modified steel showed formation of TiC dendrites that densely populated at the of the melt pool which contributes to the high hardness value. The corrosion behavior of the composite coated steel was studied using tafel extrapolation method in biodiesel environment. The surface micrograph after corrosion test shows pitting corrosion holes as a dominant corrosion phenomenon for AISI 4340 steel. The tafel curve showed reduction of corrosion current density of the surface modified steel compared to the alloy street substrate.
Effect of Gap Voltage and Pulse-On Time on Material Removal Rate for Electrical Discharge Machining of Al2O3
Authors: Moudood M.A. , Sabur Abdus , Ali Mohammad Yeakub , Jaafar I.H.
Published: July 2015

Electrical discharge machining (EDM) is a non-conventional machining technique which can be used to machine non-conductive ceramics. This technique removes materials from the workpiece by thermal energy exerted from series of electrical sparks. Using copper foil as assisting electrode (AE), machining of Al2O3 is done successfully. In this investigation, experiments were performed to study the effect of gap voltage and pulse-on time on material removal rate (MRR) for EDM of Al2O3. The results showed that the lowest and the highest values of gap voltage were 12 V and 14 V, respectively, with a fixed peak current of 1.1 A and pulse-on time of 8 μs. Beyond these two voltage values, material cannot be removed due to insufficient pyrolytic carbon layer generation. Similarly, pulse-on time is varied from 6 μs to 8 μs when gap voltage is fixed at 14 V and peak current at 1.1 A. MRR, in this case, is increased almost 20 times from a lowest value of 0.006 mm3/min to a highest value of 0.119 mm3/min for the specified gap voltage and pulse-on time.
A Light Material for Wind Turbine Blades
Authors: Al-Bat’hi Souad A.M. , AlBat’hi Souad A.M. , Buys Yose Fachmi , Hadzari Muhammad Hazwan , Othman Maizatulnisa
Published: July 2015

Nowadays, people have built mega-watt scales of wind turbines to generate electricity from wind energy. These big scales of wind turbine blade need lighter materials in order to optimize the generation of electricity. Due to this issue, purpose of this paper is to find a light material which is suitable to be used in making wind turbine blades. The use of natural fiber as a reinforcement agent in composite seems to have a big potential as natural fibers show desired characteristic needed for wind turbine blades' material. In this research, rice straw fiber was used as reinforced agent in composite with polypropylene as matrix. The composite produced was then characterized by mechanical testing which include tensile, flexural and impact as well as density measurement, dynamic mechanical testing (DMA) and Scanning Electron Microscopy (SEM). From the result obtained, it is found that the introduction of rice straw fiber to polypropylene matrix able improve the mechanical properties of the composite. The results of the composite obtained were then compared with current materials used.
Finite Element Analysis of HDPE/EPR-CNT Nanocomposite under Tensile Loading
Authors: Shaffiar N.M. , Hasnan M.A. , Anuar H. , Al Hazza Muataz Hazza Faizi
Published: July 2015

A small amount of nanodispersed filler leads to an improvement in material properties. Carbon Nanotube (CNT) is one type of filler used in nanocomposite material. A high density polyethylene/ethylene propylene rubber – carbon nanotube (HDPE/EPR-CNT) is one of the nanocomposite material that is new to the industry. This paper investigates the strength of HDPE/EPR-CNT nanocomposite under tensile loading. The experimental results of the tensile test on the nanocomposite will be compared with the tensile simulation in the Finite Element (FE) analysis for validation. The results showed that it is validated with relatively low percentage error of 0.14 % for the ultimate tensile strength and 0.05 % for the yield strength. The ultimate tensile strength of HDPE/EPR-CNT is 17.41 MPa and the yield strength is 14.9 MPa. By using CNT as a filler, the material strength is improved. The ultimate tensile strength of HDPE/EPR-CNT is the highest compared to polyethylene/ethylene propylene rubber - montmorillonite HDPE/EPR-MMT and polyethylene/ethylene propylene rubber HDPE/EPR.
Effect of Coolant Plate Geometry and Material in a Freshwater Production System: An Experimental Study
Authors: Bahar Rubina , Alam Hawlader Mohammad Nurul , Ariff Tasnim Firdaus
Published: July 2015

Channeled coolant plates have been playing an important role in the field of various heat transfer applications. Due to the “fin effect”, the overall heat transfer area increases and thus the amount of energy transfer enhances. In this study, effect of a specially designed coolant plate has been used to observe its effect on heat transfer during condensation in a freshwater production system. Compared to a flat coolant plate, the freshwater production enhanced maximum up to 50% for a coolant temperature of 25°C with this channeled plate. In addition, the plate material was varied and production enhancement was observed for the higher conductive material.
Ceramic-Polymer Composites with Low Dielectric Loss for Microwave Antennas and Wireless Sensors
Authors: Zhang Li , Yue Zhen Xing , Li Long Tu
Published: July 2015

The low dielectric loss ceramic-polymer composites were prepared by extrusion processing technique with high density polyethylene (HDPE) as matrix and high permittivity ceramic powder in BaO-Nd2O3-TiO2 (BNT) system as filter. The dielectric response in microwave frequency range was characterized, and the experimentally observed dielectric properties were compared with the theoretical models. The relative permittivity of the composites is increased from 3 to 10 with the increase in the volume fraction of BNT filter from 10 to 40 vol%. The dielectric losses of composites are less than 0.001 for all compositions. For 40 vol% ceramic loaded HDPE, the relative permittivity of 10 and loss tangent of 0.0007 at 7 GHz were obtained. The BNT-HDPE composites are promising materials for microwave dielectric antenna applications.
Wetting Behaviors of Pure Nickel and Nickel-Based Alloys on Sintered ZrB2-SiC Ceramics
Authors: Zhang Hui , Liang Han Qin , Yan Yong Jie , Liu Yan , Liu Xue Jian , Huang Zheng Ren
Published: July 2015

The wetting and spreading behaviors of pure nickel and nickel based alloys on sintered ZrB2-SiC ceramics and their interfacial microstructures were investigated in this presentation. The nickel-based alloys were mainly the commercial nickel-molybdenum-chromium products. The wetting and spreading properties were observed by a real-time thermal optical measurement system under flowing argon-5%hydrogen atmosphere. As temperature increased, the pure nickel cylinder sample on ZrB2-SiC substrate had few changes before 1228°C except for the thermal expansion in size. After that, liquid phase formed and spread gradually on the ceramic substrate. The contact angle was about 15o after holding 15min at 1600°C. Therefore, pure nickel could contact sintered ZrB2-SiC ceramics well. Meanwhile, the introduction of molybdenum and/or chromium in the pure nickel was beneficial for the wetting of nickel on sintered ZrB2-SiC ceramics. The contact angles of Ni-28Mo and Ni-16Mo-23Cr alloys on sintered ZrB2-SiC ceramics after 1600°C/15min were 13o and 2o, respectively. In addition, the temperatures of the liquid drop formed rose obviously in contrast to the pure nickel. The SEM images indicated that the interfacial microstructures of Ni-based alloys on sintered ZrB2-SiC ceramic substrates were uniform and the dissolved boundaries showed that they had a good bonding. However, some cracks were found in the Ni/ZrB2-SiC system for their high thermal mismatch. On the other hand, the Ni-Mo (-Cr)/ZrB2-SiC interface had few defections and evident elemental diffusion between the ceramic substrates and the alloys were found at the interface.
Technical note: Analytical solution for the mean drawdown of steady state pumping tests in two-dimensional isotropic heterogeneous aquifers
Authors: Zech A. , Attinger S.
Published: July 2015

Abstract. A new method is presented which allows to interpret steady state pumping test in heterogeneous isotropic transmissivity fields. In contrast to mean uniform flow, the pumping test drawdowns in heterogeneous media cannot be described by a single effective or equivalent value of hydraulic transmissivity. A radially depending description of transmissivity is required, including the parameters of aquifer heterogeneity: mean, variance and correlation length. Such a model is provided by the upscaling procedure Radial Coarse Graining, which describes the transition of near well to far field transmissivity effectively. Based on the Radial Coarse Graining Transmissivity, an analytical solution for a steady state pumping test drawdown is derived. The so-called effective well flow solution is derived for two cases: the ensemble mean of pumping tests and the drawdown at an individual heterogeneous transmissivity field. The analytical form of the solution allows to inversely estimate the parameters of aquifer heterogeneity from pumping test data. This is shown making use of virtual pumping test data, for both cases the ensemble mean drawdown and pumping tests at individual transmissivity fields. The effective well flow solution reproduces the drawdown for two-dimensional pumping tests in heterogeneous media and is a promising tool to estimate parameters of aquifer heterogeneity, in particular for the horizontal correlation length.
Looking for a Taste of Home: A Qualitative Study of the Health Implications of the Diets of Australian - Based Southeast Asian Students
Authors: Leu Jodie H. , Banwell Cathy
Published: July 2015

PURPOSE: To investigate potential dietary changes among Southeast Asian international students living in self-catered accommodation while studying abroad and to consider implications for their health.

DESIGN: Participants were interviewed about their food preferences and behaviours in their home countries and during their undergraduate studies at the Australian National University.

SETTING: A university in Australia

PARTICIPANTS: Study participants were full-time undergraduate students over 18 years of age from Southeast Asian countries studying at the Australian National University for at least one year, and living at self-catered accommodation.

METHODS: Thirty-one, in-depth, face-to-face qualitative interviews concerning usual diets were collected over a three month period in 2013. Interviews were coded and analysed with the aid of a computer program Atlas.ti.

RESULTS: The macro-nutrient content of Southeast Asian international students’ diets did not change a great deal when they moved to Australia. Most students replaced some preferred foods on occasions because they either could not afford them, they were not available or they lacked the time to prepare them. These dietary changes were not necessarily reflected in changes to students’ weights and most students considered that they were as healthy as when they lived at home.

CONCLUSION: As students’ adapt to a new food environment they reflexively manage potential health risks. Strong student networks and an accessible and healthy food environment would support students to make healthy dietary choices although additional information about healthy diets could facilitate this further.
Effectiveness of Acceptance and Commitment Therapy on Interpersonal Problemsand Psychological Flexibility in Female High School Students With Social Anxiety Disorder
Authors: Azadeh Sayedeh Monireh , Kazemi-Zahrani Hamid , Besharat Mohammad Ali
Published: July 2015

Social anxiety is a psychological disorder which has devastative and pernicious effects on interpersonal relationships and one's psychological flexibility. The aim of this research was to determine the effectiveness of Acceptance and Commitment Therapy on interpersonal problems and psychological flexibility in female high school students with social anxiety disorder. With a semi-experimental design, the subjects were assessed using the Social Anxiety Scale and clinical interview. The statistical population of the research was high school female students studying in 5 areas of Isfahan. 30 individuals were purposively selected as the sample. The subjects of the research were randomly assigned to the experimental and control groups. Acceptance and Commitment Therapy was given in 10 sessions of 90 minutes in the experimental group and the control group did not receive any treatment. Pre-test and post-test scores of Inventory of Interpersonal Problems, and Acceptance and Action Questionnaire were analyzed using multivariate analysis of variance & the results showed that after the intervention, there was a significant difference between the scores of the subjects in the experimental and control groups. This means that Acceptance and Commitment Therapy can influence interpersonal problems and their six dimensions and psychological flexibility as well.
Real Time PCR: the Use of Reference Genes and Essential Rules Required to Obtain Normalisation Data Reliable to Quantitative Gene Expression
Authors: Rocha Antônio J. , Monteiro-Júnior José E. , Freire José E.C. , Sousa Antônio J.S. , Fonteles Cristiane S.R.
Published: July 2015

Quantitative Real-time Polymerase Chain Reaction (qPCR) is an important tool for molecular biology and biotechnology research, widely used to determine the expression levels of mRNA. Two main methods to performing qPCR are largely used: The absolute quantification, in which the mRNA levels are determined by using a standard curve and the relative method, which is based on the use of reference genes. Reference genes are widely expressed in cells of animal and plant tissues and their expression pattern are theoretically unchanged within several situations, which makes them an excellent choice to normalize mRNA quantification data in relative qPCR studies. However, several reports are increasingly showing that the use of only one reference gene in relative qPCR studies should be avoided, because in the real world their expression levels can significantly change from tissue to tissue. Several softwares, such as geNorm, BestKeeper and NormFinder, have been developed to perform data normalisation, and these programs may assist in choosing the most stable reference genes. The aim of this review was to describe the current normalisation strategies used in qPCR assay, as well as to establish essential rules to perform reliable mRNA quantification. Finally, this review show some innovations in the advances on qPCR.
L’anglicisation du vocabulaire dans le Nord-Est ontarien francophone
Authors: Thomas Alain
Published: July 2015

Bien que les francophones soient presque partout minoritaires en Ontario et, par conséquent, soient constamment exposés à la langue anglaise, on connaît mal l’influence de cette dernière sur les choix lexicaux des locuteurs franco-ontariens. Outre quelques travaux sur des emprunts spécifiques et l’alternance de code, on chercherait en vain des études approfondies sur l’usage des anglicismes lexicaux dans le parler de la communauté, particulièrement dans sa dimension diachronique. Afin de tenter de combler cette lacune, une recherche sur la perception de l’utilisation des emprunts à l’anglais dans le Nord-Est de l’Ontario a été entreprise. L’étude a été menée au moyen d’un questionnaire, administré auprès de locuteurs francophones de la région, qui portait sur près de 200 mots et expressions relevés dans un roman franco-ontarien choisi pour son fréquent recours au lexique anglais. Les résultats révèlent des différences intergénérationnelles intéressantes qui suggèrent une évolution du lexique en synchronie dynamique et fournissent indirectement des renseignements sur l’attitude d’une communauté minoritaire francophone importante vis-à-vis de la langue dominante de l’Ontario.
Translating PrEP effectiveness into public health impact: key considerations for decision‐makers on cost‐effectiveness, price, regulatory issues, distributive justice and advocacy for access
Authors: Hankins Catherine , Macklin Ruth , Warren Mitchell
Published: July 2015

Introduction

The extraordinary feat of proving the effectiveness of oral pre‐exposure prophylaxis (PrEP) in clinical trials in different populations in a variety of settings may prove to have been easier than ensuring it is used well. Decision‐makers must make difficult choices to realize the promise of antiretroviral prophylaxis for their countries. This paper outlines key economic, regulatory and distributive justice issues that must be addressed for effective and acceptable PrEP implementation.

Discussion

In considering the role that PrEP can play in combination prevention programmes, decision‐makers must determine who can benefit most from PrEP, how PrEP can be provided safely and efficiently, and what kind of health system support will ensure successful implementation. To do this, they need contextualized information on disease burden by population, analyses of how PrEP services might best be delivered, and projections of the human resource and infrastructure requirements for each potential delivery model. There are cost considerations, varying cost‐effectiveness results and regulatory challenges. The principles of ethics can inform thorny discussions about who should be prioritized for oral PrEP and how best to introduce it fairly. We describe the cost‐effectiveness of PrEP in different populations at higher risk of HIV exposure, its price in low‐ and middle‐income countries, and the current regulatory situation. We explore the principles of ethics that can inform resource allocation decision‐making about PrEP anchored in distributive justice, at a time when universal access to antiretroviral treatment remains to be assured. We then highlight the role of advocacy in moving the PrEP agenda forward.

Conclusions

The time is ripe now for decisions about whether, how and for whom PrEP should be introduced into a country's HIV response. It has the potential to contribute significantly to high impact HIV prevention if it is tailored to those who can most benefit from it and if current regulatory and pricing barriers can be overcome. Advocacy at all levels can help inform decision‐making and push the access agenda to avert HIV infections among those at highest risk of HIV exposure. The benefits will accrue beyond the individual level to slow HIV transmission at the population level.
Contacts-based prediction of binding affinity in protein–protein complexes
Authors: Vangone Anna , Bonvin Alexandre MJJ
Published: July 2015

Almost all critical functions in cells rely on specific protein–protein interactions. Understanding these is therefore crucial in the investigation of biological systems. Despite all past efforts, we still lack a thorough understanding of the energetics of association of proteins. Here, we introduce a new and simple approach to predict binding affinity based on functional and structural features of the biological system, namely the network of interfacial contacts. We assess its performance against a protein–protein binding affinity benchmark and show that both experimental methods used for affinity measurements and conformational changes have a strong impact on prediction accuracy. Using a subset of complexes with reliable experimental binding affinities and combining our contacts and contact-types-based model with recent observations on the role of the non-interacting surface in protein–protein interactions, we reach a high prediction accuracy for such a diverse dataset outperforming all other tested methods.
Functional evidence implicating chromosome 7q22 haploinsufficiency in myelodysplastic syndrome pathogenesis
Authors: Wong Jasmine C , Weinfurtner Kelley M , Alzamora Maria del pilar , Kogan Scott C , Burgess Michael R , Zhang Yan , Nakitandwe Joy , Ma Jing , Cheng Jinjun , Chen Shann-Ching , Ho Theodore T , Flach Johanna , Reynaud Damien , Passegué Emmanuelle , Downing James R , Shannon Kevin
Published: July 2015

Chromosome 7 deletions are highly prevalent in myelodysplastic syndrome (MDS) and likely contribute to aberrant growth through haploinsufficiency. We generated mice with a heterozygous germ line deletion of a 2-Mb interval of chromosome band 5A3 syntenic to a commonly deleted segment of human 7q22 and show that mutant hematopoietic cells exhibit cardinal features of MDS. Specifically, the long-term hematopoietic stem cell (HSC) compartment is expanded in 5A3+/del mice, and the distribution of myeloid progenitors is altered. 5A3+/del HSCs are defective for lymphoid repopulating potential and show a myeloid lineage output bias. These cell autonomous abnormalities are exacerbated by physiologic aging and upon serial transplantation. The 5A3 deletion partially rescues defective repopulation in Gata2 mutant mice. 5A3+/del hematopoietic cells exhibit decreased expression of oxidative phosphorylation genes, increased levels of reactive oxygen species, and perturbed oxygen consumption. These studies provide the first functional data linking 7q22 deletions to MDS pathogenesis.
Transdifferentiation mediated tumor suppression by the endoplasmic reticulum stress sensor IRE-1 in C. elegans
Authors: Levi-Ferber Mor , Gian Hai , Dudkevich Reut , Henis-Korenblit Sivan
Published: July 2015

Deciphering effective ways to suppress tumor progression and to overcome acquired apoptosis resistance of tumor cells are major challenges in the tumor therapy field. We propose a new concept by which tumor progression can be suppressed by manipulating tumor cell identity. In this study, we examined the effect of ER stress on apoptosis resistant tumorous cells in a Caenorhabditis elegans germline tumor model. We discovered that ER stress suppressed the progression of the lethal germline tumor by activating the ER stress sensor IRE-1. This suppression was associated with the induction of germ cell transdifferentiation into ectopic somatic cells. Strikingly, transdifferentiation of the tumorous germ cells restored their ability to execute apoptosis and enabled their subsequent removal from the gonad. Our results indicate that tumor cell transdifferentiation has the potential to combat cancer and overcome the escape of tumor cells from the cell death machinery.
A pain-mediated neural signal induces relapse in murine autoimmune encephalomyelitis, a multiple sclerosis model
Authors: Arima Yasunobu , Kamimura Daisuke , Atsumi Toru , Harada Masaya , Kawamoto Tadafumi , Nishikawa Naoki , Stofkova Andrea , Ohki Takuto , Higuchi Kotaro , Morimoto Yuji , Wieghofer Peter , Okada Yuka , Mori Yuki , Sakoda Saburo , Saika Shizuya , Yoshioka Yoshichika , Komuro Issei , Yamashita Toshihide , Hirano Toshio , Prinz Marco , Murakami Masaaki
Published: July 2015

Although pain is a common symptom of various diseases and disorders, its contribution to disease pathogenesis is not well understood. Here we show using murine experimental autoimmune encephalomyelitis (EAE), a model for multiple sclerosis (MS), that pain induces EAE relapse. Mechanistic analysis showed that pain induction activates a sensory-sympathetic signal followed by a chemokine-mediated accumulation of MHC class II+CD11b+ cells that showed antigen-presentation activity at specific ventral vessels in the fifth lumbar cord of EAE-recovered mice. Following this accumulation, various immune cells including pathogenic CD4+ T cells recruited in the spinal cord in a manner dependent on a local chemokine inducer in endothelial cells, resulting in EAE relapse. Our results demonstrate that a pain-mediated neural signal can be transformed into an inflammation reaction at specific vessels to induce disease relapse, thus making this signal a potential therapeutic target.
The constant‐hardness creep compliance of polycrystalline ice
Authors: Caswell Tess E. , Cooper Reid F. , Goldsby David L.
Published: July 2015

We have performed creep and stress‐reduction experiments on polycrystalline ice (grain sizes, d ≈ 30 and ≈ 245 µm) in the grain boundary sliding and dislocation creep regimes (stresses σ = 0.5–5 MPa, temperature T = 233 K) to determine the constant‐hardness creep compliance under these conditions. Our results are consistent with a microstructural state‐variable description of dislocation‐effected deformation whose rate is accelerated by grain boundary sliding. The fine‐grained specimens reveal no subgrain boundaries, indicating that the stress‐sensitive microstructural feature upon which the state‐variable behavior is founded may be the dislocation structure of the grain boundaries. Deviations of our constant‐hardness data from the behavior predicted by the state‐variable formulation allow estimation of the viscosity of the grain boundaries, which is ~4.8 × 106 Pa s at this temperature.
Synthesis and Evaluation of Chroman‐4‐One Linked to N‐Benzyl Pyridinium Derivatives as New Acetylcholinesterase Inhibitors
Authors: Arab Saman , Sadat‐Ebrahimi Seyed‐Esmail , Mohammadi‐Khanaposhtani Maryam , Moradi Alireza , Nadri Hamid , Mahdavi Mohammad , Moghimi Setareh , Asadi Mehdi , Firoozpour Loghman , Pirali‐Hamedani Morteza , Shafiee Abbas , Foroumadi Alireza
Published: July 2015

A novel series of chroman‐4‐one derivatives containing the N‐benzyl pyridinium moiety were designed, synthesized, and evaluated for their acetylcholinesterase (AChE) inhibitory activities. Among the various synthesized compounds, (E)‐1‐(2,3‐dibromobenzyl)‐4‐((7‐ethoxy‐4‐oxochroman‐3‐ylidene)methyl)pyridinium bromide (8l) depicted the most potent anti‐AChE activity (IC50 = 0.048 μM). In addition, the molecular modeling study allowed us to detect possible binding modes that are in full compliance with the observed results through in vitro experiments.
Effects of Smart Charging of Multiple Electric Vehicles in Reducing Power Generation Fuel Cost
Authors: Ikegami Takashi , Yano Hitoshi , Kudo Koji , Ogimoto Kazuhiko
Published: July 2015

The high penetration of variable sources of renewable power generation will lead to operational difficulties in supply/demand balancing in the entire power system. The mass deployment of electric vehicles (EVs) and plug‐in hybrid vehicles (PHEVs) will also cause significant changes in electricity demand. Therefore, controlling and managing the charging time of EVs/PHEVs are effective approaches that are imperative for improving balancing in power system operation. We assumed travel patterns for EVs in a model of the future Tokyo power system and analyzed the power system loads, including the charging load of the EVs, under several charging control scenarios. We verified that charging time controls are substantially effective for reducing the fuel costs in the power system. Further, we found that load leveling under a multicar charging management scenario gave the best results in terms of the fuel costs in all cases.
Reduction of Ripple Current Loss by Electromagnetic Coupling of Air‐Core Reactors
Authors: Nakamura Takayuki , Taguchi Yoshiaki , Ogasa Masamichi
Published: July 2015

To reduce the loss due to ripple current in a multiphase current‐reversible chopper, we investigated electromagnetic coupling of an air‐core reactor. We derived the relationship between the amplitude of the ripple current, the duty factor, and the electromagnetic coupling coefficient, and used the results to estimate the effects of electromagnetic coupling in the design of a train energy storage system. We built reactors with electromagnetic coupling coefficients of 0.93 and 0.60. These reactors employed a new winding structure that provides an optimal electromagnetic coupling coefficient. The mass of the former type of reactor was increased by 4.4% over the conventional design, and that of the latter type of reactor was decreased by 17%. Finally, we tested the new reactors. When the chopper employs the former type of reactor and operates with equal‐phase switching and cumulative coupling, the loss due to ripple current is decreased by 11%. When the chopper employs the latter type of reactor and operates with shift‐phase switching and differential coupling, the loss is decreased to 31%. The test showed that the calculated relationships agreed with the measured values.
Capillary electrophoresis method for speciation of iron (II) and iron (III) in pharmaceuticals by dual precapillary complexation
Authors: Gotti Roberto , Fiori Jessica , Liverani Lino , Spelta Franco
Published: July 2015

Pharmaceutical iron sucrose is an iron (III) replacement for the treatment of iron deficiency anemia in patients with chronic kidney disease. The drug product (injection) is a colloidal solution of ferric hydroxide in complex with sucrose, containing 20 mg/mL elemental iron; according to United States pharmacopoeia (USP), the limit of iron (II) is 0.4% w/v. A selective CE method for the simultaneous determination of iron (III) and its potential impurity iron (II), was developed by applying a dual precapillary complexation. In particular, 1,10‐phenanthroline and 1,2‐diaminocyclohexanetetraacetic acid were used for complexation of iron (II) and iron (III), respectively. Sample preparation was optimized to achieve mineralization of pharmaceuticals using HCl 6 M, by avoiding perturbation of the oxidation status of both iron species. Simple CZE conditions, involving a 60 mM (pH 9.3) tetraborate buffer at the constant voltage of 25 KV and 25°C, allowed fast separation of iron (II) and iron (III) complexes that were detected at 265 nm. Sensitivity for iron (II) determination was found to be 4.80 μM (LOQ) corresponding to 0.15% w/w with respect to the total iron test level. The method was validated by following International Conference on Harmonization guidelines for specificity, linearity, precision, accuracy, and robustness and it was applied to real pharmaceutical samples. The obtained results suggested that the method can be a useful alternative to the official USP and British pharmacopoeia polarographic method.