bluuebunny/crossref_metadata_2025 huggingface dataset:
Fabrication and Characterization of Graphene from Solid Carbon Dioxide
Authors: Arifutzzaman Akhama , Yaacob Iskandar , Hawlader M.A. , Maleque Md Abdul
Published: July 2015

Graphene was fabricated by a well-known technique of ignition of magnesium (Mg) metal ribbon in solid carbon dioxide. Two dry ice slabs were used as carbon source for the production of graphene. A hemispherical cavity of about 3-4 cm diameter was carved on surfaces of both dry ice slabs. About 0.5g of Mg ribbon was burnt and immediately placed into the dry ice cavity. It was then covered up by another carved slab of dry ice. After complete combustion, mixture of black and white residues was formed. It was then recovered. 20 ml of 1 M HCl acid was added to the product mixture. Reaction of HCl with MgO and unburned Mg formed MgCl2 which was then washed away by deionized water. The isolated carbon material was separated as product. Characterization of the product was performed using optical microscopy (OM), where images showed the presence of sheet-like light gray objects. Field emission scanning electron microscopy (FESEM) and transmission electron microscope (TEM) analyses revealed the presences of graphene. The lateral length of the sheet was about 3-3.5 μm and the surface area was about 3-5.5 μm2 using images analysis software.
Characterization of Micromist for Effective Minimum Quantity Lubrication
Authors: Lerma I. , Jimenez M. , Edinbarough I. , Krell J. , Hung N.P.
Published: July 2015

This research characterizes flow of micromist for machining purpose. Liquid lubricant with contact angle less than 5° is chosen for best wetting on workpiece and tool materials. A high nozzle air speed of 100 m/s produces micromist with 20° spherical cone angle containing droplets of 4 μm average diameter, but smaller droplets might raise an environmental concern. Preliminary comparative tests show a significant reduction of tool wear when machining 4140 steel in minimum quantity lubrication.
Microelectrode Design for Particle Trapping on Bioanalysis Platform
Authors: Ibrahim Siti Noorjannah , Alkaisi Maan M.
Published: July 2015

Microelectrode geometry has significant influence on particles trapping techniques used on bioanalysis platforms. In this paper, the particle trapping patterns of dipole, quadrupole and octupole microelectrode using dielectrophoretic force (DEP) are discussed. The microelectrodes were constructed on a metal-insulator-metal platform, built on a silicon nitride (Si3N4) coated silicon substrate. The back contact is made from 20 nm nickel-chromium (NiCr) and 100 nm gold (Au) as the first layer. Then, SU-8-2005 (negative photoresist) is used on the second layer to create microcavities for trapping the particles. The third layer, where the three geometries were patterned, is made from 20 nm NiCr and 100 nm Au layers.
Prior to fabrication, the particles trapping patterns of the microelectrodes were profiled using a finite element software, COMSOL 3.5a. Trapping patterns for the three geometries were evaluated using polystyrene latex microbeads. Results from the experiment validate simulation studies in term of microelectrode trapping ability up to single particle efficiency. It provides the potential of converting the trapping platform into a lab-on-chip system.
Thermoelastic Solutions for Flexure of Anisotropic Cylindrical Shells
Authors: Ali J.S. Mohamed
Published: July 2015

Solutions within the framework of linear uncoupled thermoelasticity, are presented here for simply supported infinitely long anisotropic cylindrical shell panels subjected to thermal gradient. Benchmark numerical results in the form of displacements and stresses are tabulated for certain angle-ply layup useful for the assessment of improved shell theories.
Clustering Using Genetic Algorithm-Based Self-Organising Map
Authors: Hassan Azmi , Andi Purnomo Muhammad Ridwan , Annisa Putri Dwi
Published: July 2015

This paper presents a comparative study of clustering using Artificial Intelligence (AI) techniques. There are 3 methods to be compared, two methods are pure method, called Self Organising Map (SOM) which is branch of Artificial Neural Network (ANN) and Genetic Algorithm (GA), while one method is hybrid between GA and SOM, called GA-based SOM. SOM is one of the most popular method for cluster analysis. SOM will group objects based on the nearest distance between object and updateable cluster centres. However, there are disadvantages of SOM. Solution quality is depend on initial cluster centres that are generated randomly and cluster centres update algorithm is just based on a delta value without considering the searching direction. Basically, clustering case could be modelled as optimisation case. The objective function is to minimise total distance of all data to their cluster centre. Hence, GA has potentiality to be applied for clustering. Advantage of GA is it has multi searching points in finding the solution and stochastic movement from a phase to the next phase. Therefore, possibility of GA to find global optimum solution will be higher. However, there is still some possibility of GA just find near-optimum solution. The advantage of SOM is the smooth iterative procedure to improve existing cluster centres. Hybridisation of GA and SOM believed could provide better solution. In this study, there are 2 data sets used to test the performance of the three techniques. The study shows that when the solution domain is very wide then SOM and GA-based SOM perform better compared to GA while when the solution domain is not very wide then GA performs better.
Adoption and Adaptation of Japanese Manufacturing Management in an Automotive Company of Malaysia
Authors: Mohiuddin A.K.M. , Abdul Rahman Mohamed , Jabar Julia Bt Haji A.
Published: July 2015

This paper discusses the practices associated with Japanese Manufacturing Management (JMM) which can yield a superior competitive advantage in terms of productivity, quality and provide overall successful business performance. To examine the transfer of the best practices of the JMM locally and obtain the impact of the adoption and adaptation of the JMM, an in-depth case study was conducted in a Malaysian automotive company. This paper also discusses the changes in terms of the philosophy and practices undertaken by the automotive company and ascertain the impact of the JMM on its manufacturing and financial performances.
The elements of business performance from the viewpoint of manufacturing based on safety, quality, cost and delivery were quantified and examined. All elements were quantified since the first year of the adoption and viewed over time to track the trend of achievement. The results show a positive impact to the automotive plant manufacturing performance. The results of the financial performance also show the profitability of the plant. The revenue has increased up to 92% after the JMM adoption whilst the net profit has increased from 5.33% to 8.15%.
Ranking of Manufacturing Attributes Affecting Bread Quality: Application of Analytic Hierarchy Process
Authors: Nazri M.N.B.A. , Haque M. , Karim A.N. Mustafizul , Muhamad Fatima B.
Published: July 2015

Bread is considered as a prime item of cereal intake globally. Due to the rising public health concerns and their dietary needs, importance of identifying the factors in bread making, and taking necessary action plans can hardly be overemphasized. Moreover, to be competitive in business it is crucial for any bread maker to address the manufacturing factors or attributes to reduce the rejection level due to poor quality. This study makes an attempt to identify those attributes and rank them through application of analytic hierarchy process (AHP). The questionnaire is prepared to judge the ranking of initially identified five prime attributes such as ingredient quality, processing time and procedure, environment and workers’ skill. The responses by the manager, supervisor, line leader and quality control inspector on pair-wise comparison scale are collected and analyzed by using Expert Choice software along with the verification of inconsistency value. According to the results, quality of ingredient is ranked first followed by the processing time of the bread, production procedure, worker’s skill, and production environment. Since the inconsistency level is found to be below the threshold value, policies can be adopted safely in accordance with the ranking of factors to uphold the quality of bread and reduce the rejection level.
Parameter Optimization of VMI System in a Manufacturer and Multi Retailer Using Genetic Algorithm
Authors: Hassan Azmi , Saleh Chairul , Md Deros Baba , Ab Rahman Mohd Nizam , Leuveano Raden Achmad Chairdino , Adiyoga Andra
Published: July 2015

This paper presents product marketing and inventory policy for a manufacturer and multi-retailer system under vendor managed inventory (VMI) mode of operation. The aim is to maximize individual profit where each firm interacted through decentralised supply chain. For this reason, the manufacturer often considers managing the system-wide inventories by determining replenishment cycles, backorder quantity, wholesale price, and advertising investment. Also, due to the information-asymmetric VMI, retailers sequentially need to determine their optimal retail prices and advertisement policies. In order to find the optimal solution i.e. better profit equilibrium for all supply chain channel, a Genetic Algorithm is proposed in this study. The proposed algorithm is assessed for its solution quality. Furthermore, the performance evaluations are given, to present an improvement to the model.
Effects of Sintering Temperature and Porogen Addition on Properties of Low Cost Porous Mullite Ceramics
Authors: Xu Na Na , Li Shu Jing , Li Yuan Bing , Yuan Lin , Zhang Jin Long , Wang Lei
Published: July 2015

In the present paper, low cost porous mullite ceramics with high porosity, high strength and low thermal conductivity were fabricated using ceramic waste powder and clay as raw materials, and sawdust as porogen. The correlation of phase composition and physicochemical properties of such porous mullite ceramics were researched by varying sintering temperature and the extra addition of sawdust. The results show that: The ceramics show the best comprehensive properties when the sintering temperature is 1400 oC and the addition of sawdust is 30wt%. The results of SEM and EDS analysis confirm that new mullite phase is generated in the ceramics, which can strengthen the ceramics. And the best value of the bulk density, apparent porosity, cold crushing strength and the thermal conductivity of the prepared ceramics is 0.96g.cm-3,60.7%,5.3MPa and 0.212W·m-1·K-1, respectively.
Effect of Background Color to the Final Color of Four Highly Transparent Ceramics after Veneered
Authors: Huang Yang , Lu Rong Jian , Zhao Li Sheng , Yi Yuan Fu , Shao Long Quan , Wen Ning , Deng Bin
Published: July 2015

This study aimed to investigate the color value of four kinds of highly transparent ceramics (Zenostar Zirconia, Lava Zirconia, Cercon Zirconia and Upcera Zirconia)after veneered on three different post core materials including noble metal alloy, Co-Cr alloy and composite resin. Highly transparent ceramics after veneered were made into specimens with 10mm in diameter and 1.0mm in thickness. The color of core ceramics after veneered on different post core materials were measured with Color Analyzes. The results showed that their color value were significantly different from each other. Zenostar ZR Translucent and Lava Plus High Translucency Zirconia can be easily affected by the background color because of its high translucency. Therefore, resin post core materials should be selected without cause prosthesis mismatch of colors in clinical work. When making Cerconht full contour zirconia restorations, you could try to use a resin material as a post core material. And selecting precious metals, you had better make it opaque. Upcera zirconia owned a poor relative translucency, when making clinical restorations; you could use any kind of post core materials.
Dielectric Breakdown in Electrowetting-Based Liquid Microactuators
Authors: Wang Wei Qiang , Su Yan
Published: July 2015

In an electrowetting-based liquid microactuator, two types of insulating materials are used for device operation: an dielectric material to provide capacitance between the liquid and conductor, and a hydrophobic coating at the interface of liquid and insulator. This paper investigates important physical properties for the insulating materials. Several alternative dielectric materials are compared for application in EW chips, breakdown phenomenon of insulating layers with different thicknesses is tested before and after droplet actuation. It appears that the used EW devices have lower breakdown voltages than unused devices, probably due to the locally trapped charges in the insulating layer.
Preparation and Ferroelectric Properties of BaTiO3 Nanotubes
Authors: Zhu Ning , Wang Li Jie , Deng Xiang Yun
Published: July 2015

BaTiO3 nanotube arrays are prepared by hydrothermal reaction using the TiO2 nantotubes prepared by anodic oxidation reaction. The element, structure, elementary composition and ferroelectric properties are researched by SEM, XRD and TF Analyzer. The result shows that the prepared BaTiO3 arranged orderly and have tetragonal structure after annealing. The diffracted intensity increased with the hydrothermal temperature rising up. With the increasing of Ba(OH)2 concentration, remnant polarization intensity and coercive field climbed up and then decreased. With the increasing of hydrothermal temperature, remnant polarization intensity and coercive field increased. When the Ba(OH)2 concentration is 0.3mol/L, the hydrothermal temperature is 260°C,the remnant polarization and coercive field of the samples reached the maximum and respectively reached 6.69mC/cm2 and 1.32 kV/cm.
Photoswitching Characteristics of LiNbO3/ZnO/n-Si Heterojunction
Authors: Liu Yun Jie , Hao Lan Zhong , Zhu Jun , Zhang Wan Li , Yu Lian Qing , Guo Wen Yue
Published: July 2015

(001)-oriented LiNbO3 (LN) ferroelectric films were grown on (100)-oriented n-type Si substrates using 15 nm-thick ZnO layers as buffers by pulse laser deposition technique and the LN/ZnO/n-Si heterojunctions were fabricated. Obvious photoswitching characteristics to white light were observed when the reverse voltages were applied on the LN/ZnO/n-Si heterojunction. High performance was exhibited, such as a large ON/OFF ratio, short photoresponse time, steady ON or OFF states, and well reversible. The results were discussed in terms of the band diagrams of the LN/ZnO/Si heterojunctions in this work.
Effect of Annealing Treatments on Optical and Luminescence Properties of Lu1.8Y0.2SiO5:Ce Single Crystal
Authors: Fan Ling Cong , Zhang Yuan , Ji Xiao Xiao , Shi Ying , Xie Jian Jun , Lei Fang
Published: July 2015

LYSO:Ce crystal is one of efficient scintillation materials with high light output and short decay time. LYSO:Ce crystal grown by Czochralski method can be affected by annealing treatments. In present work, annealing treatments in different atmosphere (air, N2 and H2) were carried out on the LYSO:Ce crystals to investigate the effect on the optical and luminescence properties after annealing. The optical transmittance, excitation and emission spectrum, and the decay time have been attained at room temperature. Luminescence efficiency has been presented by the integrated area of emission spectra under ultraviolet (UV) excitation. It is found that annealing treatments almost do not affect the optical transmittance. Annealing in N2 atmosphere has no noteworthy effect on the luminescence intensity of LYSO:Ce crystals, but increases much annealing in H2 atmosphere, dramatically decreases the luminescence intensity after annealing in air. In addition, the decay time of LYSO:Ce crystals are affected by annealing treatment either in air or in H2 atmosphere.
Spray Pyrolysis Synthesis and Luminescence Properties of Spherical Eu3+ Doped SrMoO4 Phosphors
Authors: Wang Shun , Wang Hong Qiang
Published: July 2015

Spherical SrMoO4:Eu3+ phosphors had been prepared by spray pyrolysis. The effect of the total solution concentration on phase structure, microscopic morphology and fluorescent performances of SrMoO4: Eu3+ phosphor have been studied. The results showed that pure SrMoO4 phase can be obtained at different total solution concentration; The luminous intensity of the sample was the strongest at 615nm when the total solution concentration is 0.6M. SrMoO4: Eu3+ phosphor with regular spherical morphology, well dispersion and well fluorescent properties was synthesized successfully by spray pyrolysis method.
The Influence of Sintering Temperature on Properties of Silicon Carbide Porous Ceramic Filter Membrane
Authors: Huang Chuang Jun , Deng Xiang Yun , Sun Yang Shan , Sun Guang Hao , Guan Xin
Published: July 2015

The average particle size of SiC used as raw materials is 60 μm, the filter membrane in a mass ratio of each component are: SiC : binder: sodium carboxymethyl cellulose (CMC): deionized water =9:1:1:20. Method of producing membrane by means of spin coating, the sintering temperature was set in different ranges. The Archimedes drainage method was used to measure its porosity, and the filter pressure of membrane was charactered by the filter pressure testing system, SEM was performed to characterize its surface morphology and microstructure. The results show that: when the temperature rises from 1225 °C to 1325 °C, the filter pressure of SiC porous ceramic filter membrane decrease firstly and then increase; the atlas trend of the porosity is roughly opposite with the filter pressure, the maximum of the porosity value is about 42% when the temperature reaches 1300°C, at this temperature, the filter pressure reaches a minimum value and the surface of the filtration membrane is the most flat. When the temperature reaches 1350 °C, the surface of the film started showing a plaque.
Influence of YAG-Based Composite Sintering Aids on Gas Pressure Sintered BNw/Si3N4 Composites
Authors: Wang Xian Li , Gong Hong Yu , Zhang Yu Jun , Che Song Wei
Published: July 2015

BNw/Si3N4 composites were fabricated by gas pressure sintering process using α-Si3N4 powder and self-made BN whisker as principal raw materials. The effects of different sintering additives such as YAG, MgO+YAG and RE2O3+YAG(RE=La, Sm, Dy) on the apparent porosity, microstructure, phase composition, mechanical performance and dielectric properties of the composites were analysed. The results revealed that composite sintering aids at certain ratio (MgO/RE2O3:YAG=1:5) was more conducive to ceramic densification than single YAG additive. The BNw/Si3N4 sintered with La2O3+YAG acquired the highest density and the maximum bending strength (272.46 MPa) and fracture toughness(4.9 MPa·m1/2). It was speculated that ceramic densification process was related to formation of different eutectic liquid phases with different viscosity. Additionally, when the apparent porosity of BNw/Si3N4 composites was 20% or less, dielectric properties of the material were mainly influenced by the porosity and the value of the permittivity and dielectric loss decreased with the increase of ceramic porosity.
Analysis of the Mechanisms of Cracking Selected Transition Metal Carbides
Authors: Figiel Pawel , Wyzga Piotr , Laszkiewicz-Lukasik Jolanta , Wojteczko Kamil , Podsiadlo Marcin
Published: July 2015

Fracture toughness is one of the basic properties that determine the usefulness of these materials for structural applications. In this work, an analysis of cracking mechanism and measuring the fracture toughness of selected carbides: NbC, TaC and ZrC were carried out. Tested materials were sintered using Spark Plasma Sintering method (SPS), at 2200 °C, under a pressure of 35 MPa. Sintering time was 5 and 30 min. Commercial powders were used, with a particle size in the range from 1 to 6 microns. The powders were sintered without the addition of sintering activators.Additionally selected physical and mechanical properties have been investigated: apparent density (Archimedes method), Young's modulus (ultrasonic) and hardness (Vickers). The cracking mechanisms analysis was carried out using Scanning Electron Microscopy (SEM). Studies have shown that the highest fracture toughness, about 5.35 MPa·m1/2, characterized tantalum carbide, sintered at 2200 °C for 5 min. TaC also had the highest resistance to the formation of chipping around the Vickers indentation.
Preventing crime and violence through work and wages: The impact of the CommunityWork Programme
Authors: Bruce David
Published: July 2015

The article offers an analysis of the potential impact of the Community Work Programme (CWP) on crime and violence. The CPW is a public employment programme that was formally established within the government in 2010. The CWP may have an impact on crime and violence through a number of different ‘pathways’. One of these, the focus of this article, is through wages provided to the participants, 75% of whom are women. Notable here is the likely impact of these wages on the households of participants, including on their children and intimate partner relations. Whereas the CWP may have a beneficial impact on children in a household, there appears to be the potential that the CWP may aggravate the risk of violence, particularly for female participants who have unemployed partners. The article argues that if the crime prevention potential of the CWP is to be optimised, this motivates for providing ‘gender training’ to participants who may be at risk of intimate partner violence. In addition, limited male participation may reinforce a pattern of male exclusion, motivating for increasing the participation of men within the CWP.
Uncertainties in isoprene photochemistry and emissions: implications for the oxidative capacity of past and present atmospheres and for climate forcing agents
Authors: Achakulwisut P. , Mickley L. J. , Murray L. T. , Tai A. P. K. , Kaplan J. O. , Alexander B.
Published: July 2015

Abstract. Isoprene and its oxidation products are major players in the oxidative chemistry of the troposphere. Current understanding of the factors controlling biogenic isoprene emissions and of the fate of isoprene oxidation products in the atmosphere has been evolving rapidly. We use a climate–biosphere–chemistry modeling framework to evaluate the sensitivity of estimates of the tropospheric oxidative capacity to uncertainties in isoprene emissions and photochemistry. Our work focuses on two climate transitions: from the Last Glacial Maximum (LGM, 19 000–23 000 years BP) to the preindustrial (1770s) and from the preindustrial to the present day (1990s). We find that different oxidants have different sensitivities to the uncertainties tested in this study. Ozone is relatively insensitive, whereas OH is the most sensitive: changes in the global mean OH levels for the LGM-to-preindustrial transition range between −29 and +7 % and those for the preindustrial-to-present-day transition range between −8 and +17 % across our simulations. We find little variability in the implied relative LGM–preindustrial difference in methane emissions with respect to the uncertainties tested in this study. Conversely, estimates of the preindustrial-to-present-day and LGM-to-preindustrial changes in the global burden of secondary organic aerosol (SOA) are highly sensitive. We show that the linear relationship between tropospheric mean OH and tropospheric mean ozone photolysis rates, water vapor, and total emissions of NOx and reactive carbon – first reported in Murray et al. (2014) – does not hold across all periods with the new isoprene photochemistry mechanism. This study demonstrates how inadequacies in our current understanding of isoprene emissions and photochemistry impede our ability to constrain the oxidative capacities of the present and past atmospheres, its controlling factors, and the radiative forcing of some short-lived species such as SOA over time.
Rabies Epidemiology and Control in Ecuador
Authors: Ortiz-Prado Esteban , Ponce-Zea Jorge , Ramirez Dario , Stewart-Ibarra Anna M. , Armijos Luciana , Yockteng Jaime , Cardenas Washington Bolivar
Published: July 2015

OBJECTIVE: Describe the epidemiology and the control effort for rabies in Ecuador.

METHODS: This observational study included data from the Ecuadorian National Institute of Census and Statistics (INEC), and mortality and morbidity data reported by the Ministry of Public Health and the National Institute for Social Security. We conducted a phylogeny analyses to compare the N gene from the Challenge Virus Standard (CVS) vaccine strain used in Ecuador with published Cosmopolitan, Asian and Sylvatic strains. Descriptive and inferential statistics were used to determine the significance of the data.

RESULTS: In 1996 Ecuador suffered the highest rate of rabies per capita in the Americas, with an incidence rate of 0.56 cases per 100 000 people per year. Human and canine rabies showed a sharp decline until 2012. Between 1994 and 2014, we found a correlation of 0.925 (p<0.01) between annual cases of dog and human rabies. In 2011, there was an epidemic of sylvatic rabies transmitted to people by vampire bats (Desmodus rotundus) in the Amazon region, specifically in Morona Santiago, leading to 11 fatalities. Phylogenetic analyses of the CVS vaccine N gene showed an association with urban canine rabies strains (the Cosmopolitan lineage and Asian strains), whereas sylvatic rabies, like those reported in the Amazon region, were found to be grouped in a different clade represented mainly by bat-derived strains.

CONCLUSIONS: This study presents the first compilation of epidemiological data on rabies in Ecuador. The incidence of human and canine rabies, also known as urban rabies, has clearly decreased due to massive canine vaccination campaigns. Phylogenetic analysis of the prevailing vaccine used in the country showed a clear separation from bat-derived rabies, the source of recent rabies outbreaks. Efforts are ongoing to develop rabies vaccines that are highly specific to the rabies virus genotype circulating in the region, including sylvatic rabies. These efforts include the implementation of reverse genetics to generate recombinant virus coding for the prevailing glycoprotein gene.
Beyond “getting drugs into bodies”: social science perspectives on pre‐exposure prophylaxis for HIV
Authors: Auerbach Judith D , Hoppe Trevor A
Published: July 2015

Social scientists have much to contribute to the analysis of the real and potential contribution of pre‐exposure prophylaxis (PrEP) to HIV prevention around the world. Beyond just a matter of clinical efficacy and getting pills into people's mouths, PrEP raises a number of important social‐psychological questions that must be attended to in order to translate biomedical and clinical findings into uptake of PrEP among enough people at risk of HIV infection to produce population‐level effectiveness. PrEP is a dynamic phenomenon with “dialectical” attributes that invite both optimism and cynicism as a desirable and effective HIV prevention strategy. PrEP disrupts traditional notions of “safe” and “unsafe” sex; it confers on its users a level of agency and control not generally achieved with condoms; and it affects sexual practices and sexual cultures in meaningful ways. As these dynamics play out in different contexts, and as new modes of PrEP administration emerge, it will be important for social scientists to be engaged in assessing their impact on PrEP implementation and effectiveness.
Pre‐exposure prophylaxis for men and transgender women who have sex with men in Brazil: opportunities and challenges
Authors: Veloso Valdilea G , Mesquita Fabio , Grinsztejn Beatriz
Published: July 2015

Introduction

The World Health Organization recently released guidelines on the use of pre‐exposure prophylaxis (PrEP) for prevention of HIV infection among men and transgender women (TGW) who have sex with men based on results of randomized clinical trials. The aim of this commentary is to discuss the opportunities and challenges of incorporating PrEP into the Brazilian continuum of HIV care and prevention for men who have sex with men (MSM) and TGW.

Discussion

Key aspects of the AIDS epidemic among MSM and TGW in Brazil and the comprehensive Brazilian response to the epidemic are presented. The universal access to health care provided through the Brazilian Unified Health System (SUS) and the range of prevention and care services already available countrywide to HIV‐positive individuals and at‐risk MSM and TGW are identified as the main facilitators for the implementation of PrEP. Limited PrEP awareness among MSM, TGW and health care providers, low HIV testing frequency and low HIV risk perception among MSM and TGW represent the core challenges to be addressed. Data generated by demonstration projects in Brazil will provide an important contribution to PrEP rollout in Brazil.

Conclusions

The implementation of PrEP in Brazil is feasible. A synergistic rollout of treatment as prevention and PrEP will maximize public health and individual benefits of the country's comprehensive response to the AIDS epidemic.
Enhancement in Organic Photovoltaic Efficiency through the Synergistic Interplay of Molecular Donor Hydrogen Bonding and π‐Stacking
Authors: Shewmon Nathan T. , Watkins Davita L. , Galindo Johan F. , Zerdan Raghida Bou , Chen Jihua , Keum Jong , Roitberg Adrian E. , Xue Jiangeng , Castellano Ronald K.
Published: July 2015

For organic photovoltaic (OPV) cells based on the bulk heterojunction (BHJ) structure, it remains challenging to rationally control the degree of phase separation and percolation within blends of donors and acceptors to secure optimal charge separation and transport. Reported is a bottom‐up, supramolecular approach to BHJ OPVs wherein tailored hydrogen bonding (H‐bonding) interactions between π‐conjugated electron donor molecules encourage formation of vertically aligned donor π‐stacks while simultaneously suppressing lateral aggregation; the programmed arrangement facilitates fine mixing with fullerene acceptors and efficient charge transport. The approach is illustrated using conventional linear or branched quaterthiophene donor chromophores outfitted with terminal functional groups that are either capable or incapable of self‐complementary H‐bonding. When applied to OPVs, the H‐bond capable donors yield a twofold enhancement in power conversion efficiency relative to the comparator systems, with a maximum external quantum efficiency of 64%. H‐bond promoted assembly results in redshifted absorption (in neat films and donor:C60blends) and enhanced charge collection efficiency despite disparate donor chromophore structure. Both features positively impact photocurrent and fill factor in OPV devices. Film structural characterization by atomic force microscopy, transmission electron microscopy, and grazing incidence wide angle X‐ray scattering reveals a synergistic interplay of lateral H‐bonding interactions and vertical π‐stacking for directing the favorable morphology of the BHJ.
Significance of Average Domain Purity and Mixed Domains on the Photovoltaic Performance of High‐Efficiency Solution‐Processed Small‐Molecule BHJ Solar Cells
Authors: Mukherjee Subhrangsu , Proctor Christopher M. , Bazan Guillermo C. , Nguyen Thuc‐Quyen , Ade Harald
Published: July 2015

Whereas the role of molecularly mixed domains in organic photovoltaic devices for charge generation is extensively discussed in the literature, the impact on charge recombination and thus fill factor is largely unexplored. Here, a combination of soft X‐ray techniques enables the quantification of phases at multiple length scales to reveal their role regarding charge recombination in a highly efficient solution processed small molecule system 7,7′‐(4,4‐bis(2‐ethylhexyl)‐4H‐silolo[3,2‐b:4,5‐b′]dithiophene‐2,6‐diyl)bis(6‐fluoro‐4‐(5′‐hexyl‐[2,2′‐bithiophen]‐5‐yl)benzo[c][1,2,5]thiadiazole) (p‐DTS(FBTTh2)2) . A quantitative (linear) relationship between the average composition variations and the device fill‐factor is observed. The results establish the complex interrelationship between average phase purity, domain size, and structural order and highlight the requirement of achieving sufficient phase purities to diminish bimolecular and geminate recombination in solution processed small molecule solar cells.
Serum fibrosis biomarkers predict death and graft loss in liver transplantation recipients
Authors: Bhat Mamatha , Ghali Peter , Rollet‐Kurhajec Kathleen C. , Bhat Aparna , Wong Philip , Deschenes Marc , Sebastiani Giada
Published: July 2015

Noninvasive serum fibrosis biomarkers predict clinical outcomes in pretransplant patients with chronic liver disease. We investigated the role of serum fibrosis biomarkers and of changes in biomarkers in predicting death and graft loss after liver transplantation (LT). We included 547 patients who underwent LT between 1991 and 2012 and who met the following criteria: patient and graft survival > 12 months; serum fibrosis biomarkers aspartate aminotransferase–to‐platelet ratio index (APRI), fibrosis score 4 (FIB‐4), and nonalcoholic fatty liver disease (NAFLD) fibrosis score available at 1 year after LT; and a minimum follow‐up of 1 year. Delta of fibrosis biomarkers was defined as (end of follow‐up score – baseline score)/follow‐up duration. Baseline and delta fibrosis biomarkers were associated with death: APRI > 1.5 (adjusted hazard ratio [aHR], 2.2; 95% confidence interval [CI], 1.4‐3.3; P < 0.001) and delta APRI > 0.5 (aHR, 5.3; 95% CI, 3.4‐8.2; P < 0.001); FIB‐4 > 3.3 (aHR, 1.9; 95% CI, 1.3‐2.8; P = 0.002) and delta FIB‐4 > 1.4 (aHR, 2.4; 95% CI, 1.4‐4.1; P = 0.001); and NAFLD fibrosis score > 0.7 (aHR, 1.9; 95% CI, 1.3‐2.9; P = 0.002) and delta NAFLD fibrosis score (aHR, 3.7; 95% CI, 2.6‐5.4; P < 0.001). Baseline and delta fibrosis biomarkers were associated also with graft loss. In conclusion, serum fibrosis biomarkers 1 year after LT and changes in serum fibrosis biomarkers predict death and graft loss in LT recipients. They may help in risk stratification of LT recipients and identify patients requiring closer monitoring. Liver Transpl 21:1383‐1394, 2015. © 2015 AASLD.
Repeatability and variability of myocardial perfusion imaging techniques in mice: Comparison of arterial spin labeling and first‐pass contrast‐enhanced MRI
Authors: Naresh Nivedita K. , Chen Xiao , Moran Eric , Tian Yikui , French Brent A. , Epstein Frederick H.
Published: July 2015

Purpose

Preclinical imaging of myocardial blood flow (MBF) can elucidate molecular mechanisms underlying cardiovascular disease. We compared the repeatability and variability of two methods, first‐pass MRI and arterial spin labeling (ASL), for imaging MBF in mice.

Methods

Quantitative perfusion MRI in mice was performed using both methods at rest, with a vasodilator, and one day after myocardial infarction. Image quality (score of 1–5; 5 best), between‐session coefficient of variability (CVbs), intra‐user coefficient of variability (CVintra‐user), and inter‐user coefficient of variability (CVinter‐user) were assessed. Acquisition time was 1–2 min for first‐pass MRI and approximately 40 min for ASL.

Results

Image quality was higher for ASL (3.94 ± 0.09 versus 2.88 ± 0.10; P < 0.05). Infarct zone CVbs was lower with first‐pass (17 ± 3% versus 46 ± 9%; P < 0.05). The stress perfusion CVintra‐user was lower for ASL (3 ± 1% versus 14 ± 3%; P < 0.05). The stress perfusion CVinter‐user was lower for ASL (4 ± 1% versus 17 ± 4%; P < 0.05).

Conclusion

For low MBF conditions such as infarct, first‐pass MRI is preferred due to better repeatability and variability. At high MBF such as at vasodilation, ASL may be more suitable due to superior image quality and lower user variability. First‐pass MRI has a substantial speed advantage. Magn Reson Med 75:2394–2405, 2016. © 2015 Wiley Periodicals, Inc.
Post-Outbreak Investigation of Pseudomonas aeruginosa Faucet Contamination by Quantitative Polymerase Chain Reaction and Environmental Factors Affecting Positivity
Authors: Bédard Emilie , Laferrière Céline , Charron Dominique , Lalancette Cindy , Renaud Christian , Desmarais Nadia , Déziel Eric , Prévost Michèle
Published: July 2015

OBJECTIVE

To perform a post-outbreak prospective study of the Pseudomonas aeruginosa contamination at the faucets (water, aerator and drain) by culture and quantitative polymerase chain reaction (qPCR) and to assess environmental factors influencing occurrence

SETTING

A 450-bed pediatric university hospital in Montreal, Canada

METHODS

Water, aerator swab, and drain swab samples were collected from faucets and analyzed by culture and qPCR for the post-outbreak investigation. Water microbial and physicochemical parameters were measured, and a detailed characterization of the sink environmental and design parameters was performed.

RESULTS

The outbreak genotyping investigation identified drains and aerators as the source of infection. The implementation of corrective measures was effective, but post-outbreak sampling using qPCR revealed 50% positivity for P. aeruginosa remaining in the water compared with 7% by culture. P. aeruginosa was recovered in the water, the aerator, and the drain in 21% of sinks. Drain alignment vs the faucet and water microbial quality were significant factors associated with water positivity, whereas P. aeruginosa load in the water was an average of 2 log higher for faucets with a positive aerator.

CONCLUSIONS

P. aeruginosa contamination in various components of sink environments was still detected several years after the resolution of an outbreak in a pediatric university hospital. Although contamination is often not detectable in water samples by culture, P. aeruginosa is present and can recover its culturability under favorable conditions. The importance of having clear maintenance protocols for water systems, including the drainage components, is highlighted.

Infect. Control Hosp. Epidemiol. 2015;36(11):1283–1291
On the coupling between spin-up and aspect ratio of vortices in rotating stratified flows: a predictive model
Authors: Ungarish Marius
Published: July 2015

We consider the long-time (many revolutions) behaviour of an axisymmetric isolated anticyclonic vortex of constant density which floats inside a large ambient linear-stratified fluid rotating with constant ${\it\Omega}$. We have developed a closed simple model for the prediction of the vertical thickness to diameter aspect ratio ${\it\alpha}$ (and actually the shape) and internal angular velocity ${\it\omega}$, relative to the ambient, as functions of time $t$. (In our model ${\it\omega}$ is scaled with ${\it\Omega}$; the literature sometimes uses the Rossby number $Ro={\it\omega}/2$.) This model is an extension of the model of Aubert et al. (J. Fluid Mech., vol. 706, 2012, pp. 34–45) and Hassanzadeh et al. (J. Fluid Mech., vol. 706, 2012, pp. 46–57), which derived the connection between ${\it\alpha}$ and ${\it\omega}$, for prescribed $f=2{\it\Omega}$ and buoyancy frequency of the ambient $\mathscr{N}$. This work adds the balance of angular momentum and resolves the spin-up process of the vortex, which were not accounted for in the previous model. The Ekman number $E={\it\nu}/({\it\Omega}L^{2})$ now enters into the formulation; here ${\it\nu}$ is the coefficient of kinematic viscosity and $L$ is the half-height of the vortex, roughly (a sharper definition is given in the paper). The model can be applied to cases of both fixed-volume and injection-sustained vortices.

The often-cited aspect ratio ${\it\alpha}=0.5f/\mathscr{N}$ corresponds to ${\it\omega}\approx -1$, which is a plausible initial condition for typical systems. We show that the continuous ‘decay’ of ${\it\alpha}$ from that value over many revolutions of the system is indeed governed by the spin-up effect which reduces $|{\it\omega}|$, but with significant differences to the classical spin-up of a fluid in a closed solid container. The spin-up shear torque decays with time because the thickness of the boundary shear layer increases. The layer starts as a double Ekman layer (between two fluids) but it quite quickly expands due to stratification effects, and later due to viscous diffusion. This prolongs the spin-up somewhat beyond the classical $E^{-1/2}/{\it\Omega}$ time interval. Moreover, when $|{\it\omega}|$ becomes small, the momentum of angular inertia of the vortex increases like $(1+(1/3)|{\it\omega}|^{-1})$; this further hinders the spin-up, and prolongs the process.

Comparisons of the prediction of the model with previously published experimental and Navier–Stokes simulation data were performed for four cases. In three cases the agreement is good. In one case, the model predicts a much faster decay than the observed one; we have suggested a plausible explanation for this discrepancy.
Genetic diversity of Dioscorea japonica germplasm in Taiwan revealed by inter-simple sequence repeat DNA markers
Authors: Kung Tsai-Li , Lin Kuan-Hung , Lin Shun-Fu
Published: July 2015

There are three native varieties of edible yams (Dioscorea japonica Thunb.) in Taiwan, but germplasm has been collected from only a few. To assess the genetic diversity of 99 accessions collected from four geographically diverse regions, inter-simple sequence repeat (ISSR) DNA markers were analysed, and 90.2% of the polymorphic markers in these accessions were found. Genetic similarity among accessions ranged from 30.8 to 74.4%, averaging 48.4%. Cluster analyses revealed four main clusters plus one outlier (Dioscorea alata L.). The varieties oldhamii and pseudojaponica were separated into different clusters and var. japonica was grouped with both varieties. Since var. japonica was found to be genetically similar to var. oldhamii and var. pseudojaponica, we suggest that var. japonica is a hybrid or intermediate variety between the two varieties. Molecular analysis of variance results indicated that variation within counties (95.94%) was predominantly greater than variation among counties (3.63%) and among regions (0.43%). Overall, gene flow (Nm= 0.970) estimated from genetic differentiation (Gst= 0.340) suggests that gene flow among regions is relatively high. The highest genetic diversity (H= 0.191) and Shannon's index (I= 0.312), and a high gene flow (Nm= 3.926) of germplasm in the northern region suggest that this region is a possible centre of dispersal and domestication of yams in Taiwan. This study provided valuable information for germplasm collection and genetic improvement.
Mother-Youth Acculturation Gaps and Health-Risking/Emotional Problems among Latin-American Adolescents
Authors: Wiesner Margit , Arbona Consuelo , Capaldi Deborah M. , Kim Hyoun K. , Kaplan Charles D.
Published: July 2015

Second-generation Latin-American adolescents tend to show higher levels of various health-risking behaviors and emotional problems than first-generation Latin-American adolescents. This cross-sectional study of 40 mother-adolescent dyads examined the association of mother-youth acculturation gaps to youth adjustment problems. Intergenerational acculturation gaps were assessed as a bidimensional self-report component and a novel observational measurement component. The Latin-American adolescents were predominantly second-generation of Mexican descent (Mage= 13.42 years,SD= 0.55). Most of the mothers were born in Mexico (Mage= 39.18 years,SD= 5.17). Data were collected from mothers, adolescents, and coders, using questionnaires, structured interviews, and videotaped mother-youth interaction tasks. Findings revealed generally weak support for the acculturation gap-distress hypothesis. In addition, stronger relative adherence to their heritage culture by the adolescents was significantly (p< .05,ES= 0.15) related to less engagement in early health-risking sexual behaviors, possibly reflecting selective acculturation processes. Mother-youth acculturation gaps in orientation to the heritage culture were the most salient dimension, changing the focus on the original formulation of the acculturation gap-distress hypothesis.
Label-free molecular beacon-based quadratic isothermal exponential amplification: a simple and sensitive one-pot method to detect DNA methyltransferase activity
Authors: Xue Qingwang , Wang Lei , Jiang Wei
Published: July 2015

An illustration of the label-free molecular beacon-mediated quadratic isothermal exponential amplification strategy (LFMB-QIEA) for target Dam MTase detection.
DFT study on endohedral and exohedral B38fullerenes: M@B38(M = Sc, Y, Ti) and M&B38(M = Nb, Fe, Co, Ni)
Authors: Lu Qi Liang , Luo Qi Quan , Li Yi De , Huang Shou Guo
Published: July 2015

Viability of endohedral and exohedral B38fullerenes with transition metal atoms was investigated using density functional theory. M@B38(M = Sc, Y, Ti) possess endohedral structures as their lowest energy structures.
Health properties of oca (Oxalis tuberosa) and yacon (Smallanthus sonchifolius)
Authors: Jimenez María Eugenia , Rossi Analia , Sammán Norma
Published: July 2015

Andean roots and tubers are underexploited crops; many contain compounds beneficial to health, so a greater knowledge of their properties is important for encouraging their consumption.
Mechanism of the antiadipogenic-antiobesity effects of a rice hull smoke extract in 3T3-L1 preadipocyte cells and in mice on a high-fat diet
Authors: Kim Sung Phil , Nam Seok Hyun , Friedman Mendel
Published: July 2015

Photomicrographs and dose-dependent lipid reduction in adipocyte cells induced by the rice hull extract.
In vivo targeted imaging of early stage prostate cancer using a transferrin based near-infrared fluorescence probe
Authors: Zhao Yang , Peng Jing , Niu Yuanjie , Zhang Xuening , Jiang Ning , Jia Rongrong , Li Jiang , Shang Zhiqun , Zhu Shimiao , Sun Libin
Published: July 2015

Intravenous injection of Tf-Au NCs could be applied in the targeted imaging and early diagnosis of prostate cancer in vivo.
A facile method to synthesize [A′(D′AD)2]-based push–pull small molecules for organic photovoltaics
Authors: Shaker Mohamed , Lee Jong-Hoon , Trinh Cuc Kim , Kim Wonbin , Lee Kwanghee , Lee Jae-Suk
Published: July 2015

Synthesis of promising new composition low band gap small molecules based on the push–pull (donor–acceptor) system, which displayed power conversion efficiency of up to 3.24%.
Correction: Photoluminescent and cathodoluminescent performances of Tb3+ in Lu3+-stabilized gadolinium aluminate garnet solid-solutions of [(Gd1−xLux)1−yTby]3Al5O12
Authors: Li Ji-Guang , Li Jinkai , Zhu Qi , Wang Xuejiao , Li Xiaodong , Sun Xudong , Sakka Yoshio
Published: July 2015

Correction for ‘Photoluminescent and cathodoluminescent performances of Tb3+ in Lu3+-stabilized gadolinium aluminate garnet solid-solutions of [(Gd1−xLux)1−yTby]3Al5O12’ by Ji-Guang Li et al., RSC Adv., 2015, 5, 59686–59695.
Pyridine-enabled copper-promoted cross dehydrogenative coupling of C(sp2)–H and unactivated C(sp3)–H bonds
Authors: Wu Xuesong , Zhao Yan , Ge Haibo
Published: July 2015

Pyridine-enabled cross dehydrogenative coupling of sp2 C–H bonds of polyfluoroarenes and unactivated sp3 C–H bonds of amides was achieved.
Effect of Whole Grain Wheat Flour on the Mixing Properties, Oil Uptake, and In Vitro Starch Digestibility of Instant Fried Noodles
Authors: Bae In Young , Kim Hyeon Ji , Inglett George E. , Lee Suyong
Published: July 2015

The effects of whole grain wheat (WGW) flour on the quality attributes of instant fried noodles were characterized in terms of mixing and oil‐resisting properties as well as in vitro starch digestibility. Higher water absorption and shorter kneading time were required to obtain the optimally mixed dough from WGW flour, and the presence of nonstarch components in the WGW flour lowered the thermal conductivity of the noodles. The use of WGW flour produced instant fried noodles with oil uptake reduced by 30%, which could be correlated with the less porous structure confirmed by the surface and cross‐sectional scanning electron microscope images. When the instant fried noodles were subjected to in vitro starch digestion, the use of WGW flour was effective in suppressing the hydrolysis of starch in the noodles, and the predicted glycemic index of the WGW noodles (80.6) was significantly lower than that of the white wheat noodles (83.3).