bluuebunny/crossref_metadata_2025 huggingface dataset:
Constitutive Modeling for the Simulation of the Superplastic Forming of AA5083
Authors: Jarrar Firas , Jafar Reem , Tulupova Olga , Enikeev Farid , Al-Huniti Naser
Published: January 2016

The AA5083 alloy is already being used in applications that require lightweight construction and moderate strengths. In order to carry out accurate simulations of the superplastic forming of this alloy, the used constitutive models should be able to predict the deformation and thinning behavior during the forming process. In this paper, we compare the dome height and pole thickness evolution during gas bulge forming using different AA5083 constitutive material models. The models considered have different levels of complexity and are fitted using either tensile or biaxial experimental data. The simulation results are also compared with experimental data from literature. In addition, recommendations are made for developing accurate material models for the considered AA5083 alloy.
New Technologies Development and Equipment for Local Shape-Forming of the Complicated Parts Made of Heat-Resistant Alloys under Superplastic Deformation Conditions
Authors: Utyashev Farid , Mulyukov Radik , Sukhorukov Rafael , Valitov Vener
Published: January 2016

The results of development of new resource-saving technologies of local shape-forming under superplastic deformation conditions (SP) by means of roll-forming and rotary swaging are presented. These technologies are efficient for fabrication of discs, shells, rings up to 800 mm in diameter, as well as hollow shafts made of heat-resistant nickel-, titanium-and iron-based alloys that are used in aircraft engines and ground power installations. In particular, to implement innovative technologies a universal SRZhD-800 roll-forming mill has been developed for discs roll-forming made of heat-resistant alloys under SP. An efficiency of using of semi-finished products with prepared ultrafine grained (UFG) structure for generating precise complex geometry profile parts both homogeneous and regulated structure that changing in the radial direction of the disc and for obtaining high mechanical properties that are optimized taking operational conditions into account is proved. The technological process of rotary swaging under SP conditions has been developed for fabrication parts made of high alloy heat-resistant alloys using demountable mandrels. This method allows to obtain precise complex geometry profile parts such as disc with a thin cone flange which is characterized by homogeneous structure and high mechanical properties.
The Role of a Threshold Stress on the Superplasticity of Ceramics Revisited
Authors: Retamal Cesar , Lagos Miguel , Moshtaghioun Bibi Malmal , Gómez-García Diego
Published: January 2016

This paper is a brief review of the concept of superplasticity, which has been extensively used to explain the superplastic behavior of yttria-tetragonal zirconia polycrystals. The diverse theories develop to account for the origin of this quantity are outlined. In addition to that, a modern approach to this concept is reported. This new contribution can give rise to a revision of the until-now established concept of invariant microstructure associated to superplasticity.
Effect of Urea Formaldehyde Addition to the Dimensional Stability of Particle Board Made Using Glutardialdehyde Modified Corn Starch as Binder with FT-IR Analysis
Authors: Mohamad Amini Mohd Hazim , Hashim Rokiah , Sulaiman Nurul Syuhada , Hiziroglu Salim , Sulaiman Othman , Mohamed Mazlan , Sarmin Siti Noorbaini , Masri Mohamad Najmi , Sulaiman Muhammad Azwadi , Abu Bakar Mohamad Bashree
Published: January 2016

The objective of the study was to evaluate the dimensional stability of experimental particle board panels made from rubberwood (Hevea brasiliensis) using modified starch as binder. Panels were manufactured using 15% corn starch modified with glutardialdehyde and 13% modified starch with 2% Urea Formaldehyde resin as improvement. The particle boards were tested for their dimensional stability towards moisture. Results found that the 2% replacement of modified starch with urea formaldehyde resin showed increment in dimensional stability compared to using glutardialdehyde modified corn starch only as the binder, recorded at 39.38 % and 23.47 % for particleboard with 0.80 g/cm3 density after exposed to 75% and 95 % relative humidity. Therefore, this study indicated that combination of modified corn starch and urea formaldehyde resin can have a potential to be used as an improved binder to produce particle board panels with accepted properties.The objective of the study was to evaluate the dimensional stability of experimental particle board panels made from rubberwood (Hevea brasiliensis) using modified starch as binder. Panels were manufactured using 15% corn starch modified with glutardialdehyde and 13% modified starch with 2% Urea Formaldehyde resin as improvement. The particle boards were tested for their dimensional stability towards moisture. Results found that the 2% replacement of modified starch with urea formaldehyde resin showed increment in dimensional stability compared to using glutardialdehyde modified corn starch only as the binder, recorded at 39.38 % and 23.47 % for particleboard with 0.80 g/cm3 density after exposed to 75% and 95 % relative humidity. Therefore, this study indicated that combination of modified corn starch and urea formaldehyde resin can have a potential to be used as an improved binder to produce particle board panels with accepted properties.
Effect of Stirring and Aging Time on the Formation of β-Tricalcium Phosphate (β-TCP) Powder
Authors: Kasim Shah Rizal , Mohd Noor Siti Noor Fazliah , Ahmad Zainal Arifin
Published: January 2016

In this research, the effect of stirring and aging time on the formation of β-tricalcium phosphate (β-TCP) powder was studied. β-TCP powder was synthesized using calcium nitrate tetrahydrate (Ca(NO3)2.4H2O) (0.6M) and diammonium hydrogen phosphate (NH4)2HPO4) (0.4M) via wet precipitation method. The mixture was stirred with different duration (1, 3, 5 and 7 hours) then centrifuged before washed with distilled water (twice) and ethanol followed by drying in oven (80°C, 24 hours). The cake was ground to form powder. The as prepared powder was analyzed using thermo-gravimetric (TGA) to determine the suitable calcinations temperature. TGA results show that the proper calcinations temperature was 800°C. The formation of β-TCP was characterized using X-ray Diffraction (XRD) analysis. Sample with optimum formation of β-TCP phase will choose for further study on the effect of aging time (0.5, 1, 20 and 24 hours). XRD analysis confirmed that sample stirred for 7 hours and aging for 24 hours produced β-TCP as major phase. Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) proved that β-TCP powder form as agglomerated particles
Why a Comprehensive Physical Characterization Effort of Microdialysis Membranes is Imperative for Computational Mass Transfer Studies?
Authors: Abdullah Norazharuddin Shah , Min Kho Chun , Ahmad Zainal Arifin , Siti Kartini Enche Ab Rahim
Published: January 2016

Microdialysis, being a well-established sampling technique, still suffers from mass transfer limitations. Arguably, the biggest contributor to mass transfer limitation in this case is the membrane layer. To reduce limitations to mass transfer, and at the same time, increasing the performance of microdialysis probes, a concise mass transfer analysis must be done. For microdialysis probes, being relatively small in size and operating under possibly stringent biological conditions, an experimental route of analysis is less preferred compared to a computational route. This paper looks at the needs of computational mass transfer studies, and provides an idea why a comprehensive physical characterization effort is imperative for computational mass transfer studies.
Improvement of Porous Porcelain through Glaze Coating
Authors: Jamaludin Abdul Rashid , Kasim Shah Rizal , Abdullah Mohd Zulkifly , Ahmad Zainal Arifin
Published: January 2016

The dip coating procedure led to accumulation of coating particles at the coating solution and substrate interface. After sintered, frit dissolution implied an occurrence of liquid phase sintering. Simultaneous improvement of surface morphology and bulk density was evident. The significant appearance of cracks and roughed surface of plain porcelain was revolved into crack free and smoother exterior following the dip-coating and sintering process. The surface was properly glazed. This led to enhanced body densification, and sealing of apparent micropores. At the same time, the deposited coating reduced the amounts of open cells and surface defects, which caused reduction in porosity and increment of bulk density.
Investigation of Surface Properties of Titanium Treated with Combined Alkali and Sodium Removal Treatments
Authors: Tan Kwok Joon , Idris Maizlinda Izwana , Abdullah Hasan Zuhudi
Published: January 2016

Recent studies revealed the incorporation of sodium removal treatment in between alkali and heat treatments to prepare a sodium-free bioactive surface on titanium. This method has been reported to be more effective than conventional alkali and heat treatments to promote titanium osteointegration. This study aims to investigate the surface properties of high purity titanium after subjected to alkali treatment and subsequent sodium removal treatment. High purity titanium foils were immersed in 5 M NaOH at 60 °C for 24 hours followed by immersion in diluted HCl acid and/or distilled water at 40 °C for a period of time. The surface morphology and composition were examined using Field Emission Scanning Electron Microscope/Energy-Dispersive X-Ray Spectroscopy (FESEM/EDS). The surface wettability was evaluated by water contact angle. The surface functional groups were analysed using Fourier Transform Infrared Spectroscopy (FTIR). It was revealed that alkali and subsequent sodium removal treatments have rendered these samples high wettability and surface energy with the introduction of hydroxyl groups. Furthermore, diluted HCl treatment, water treatment and combination of both treatments removed sodium from the surfaces of alkali-treated titanium effectively (<5wt% Na) without altering existing hydroxyl groups.
The Effect of Boron Oxide on Phosphate Ion Released from Borosilicate Glass in Seawater
Authors: Yusof Nurul Fariha , Ku Bulat Ku Halim , Badarulzaman Nur Azam , Muhamad Nor Mohd Al Amin
Published: January 2016

Glasses in the system [wt%: (55-x)% SiO2-(15+x)% B2O3-15% P2O5-10% Na2CO3-5% Fe2O3] where 15 ≤ x ≤ 40 % have been prepared with the different amount (35-55 wt%) of boron oxide. The compositions were limited by fixing the P2O5 at 15 wt%, Na2CO3 at 10 wt% and fixing the Fe2O3 at 5 wt%. The objective of this study is to determine the effect of boron oxide on phosphate ion released from borosilicate glass in seawater. The glass has been prepared by melting in the alumina crucible within 2 hours of soaking time at 1300 °C in the furnace and cooled to room temperature. The obtained glass was crashed and sieved with yielding a mean size of 710 μm. The samples were immersed in seawater under dynamic condition by stirring at 310 rpm. The water sample was taken 6 times at every 15 minutes until 75 minutes and analyzed using Discrete Auto Analyzer. The functional group and morphological characterization on the glass surface have been investigated using Fourier Transform Infrared (FTIR) and Scanning Electron Microscopy (SEM). Analysis of the data indicates that the amount of 50 wt% boron was the best and optimum for the phosphate ion release which is 126.53 ppm.
Effect of Temperature on TiO2/ZnO Nanostructure Thin Films
Authors: Zulkiflee Nur Syahraain , Hussin Rosniza
Published: January 2016

TiO2/ZnO nanostructured thin films were grown using sol-gel route. The nanostructured thin films were deposited by dip coating method on glass substrates and calcined at different temperatures (400°C, 500°C, and 600°C). The thin films were characterized using X-Ray Diffraction method (XRD), Atomic Force Microscope (AFM), and Ultraviolet Visible Spectroscopy (UV-Vis). The XRD pattern showed that the crystallinity of the calcined thin films had improved when the calcination temperature was increased. According to AFM observation and analysis, surface roughness of the thin films controllable via growth condition. While the transmittance percentage of ultraviolet by Titanium Dioxide (TiO2) thin films through UV-Vis could be improved by combination with Zinc Oxide (ZnO). The percentage of transmittance by TiO2/ZnO nanostructured thin films continue to improve as the calcination temperature were increased.
Optimization Processing Parameter of 6061-T6 Alloy Friction Stir Welded Using Taguchi Technique
Authors: Mohd Hanapi Mohd Haslam , Hussain Zuhailawati , Almanar Indra Putra , Abu Seman Anasyida
Published: January 2016

Taguchi approach was applied to evaluate the processing parameter to determine the most influential control factors which will yield better tensile strength of friction stir welded joint of 6061-T6 aluminium alloy. The processing parameters involved are tool shoulder diameter, in mm (18 ,20, 22), tool rotational speed, in rpm (410, 865, 1140), and feed rate, in mm/min (22, 32, 45). Taguchi parametric design and optimization approach was used. Through the Taguchi parametric design approach, the optimum levels of process parameters were determined. The results indicate that the shoulder size, rotational speed, and feed rate are the significant parameters influencing the tensile strength and hardness of the joint. The predicted optimal values of tensile strength 6061-T6 aluminium alloy is 321.16 MPa. The results was confirmed by further experiments, where the experimented values for tensile strength is 301.28 MPa.
Reduction Behaviour of WO3 to W under Carbon Monoxide Atmosphere
Authors: Salleh Fairous , Tengku Saharuddin Tengku Shafazila , Samsuri Alinda , Othaman Rizafizah , Mohamed Hisham Mohamed Wahab , Yarmo Mohd Ambar
Published: January 2016

The reduction behaviour of tungsten oxide has been studied by using temperature programmed reduction (TPR) and X-ray diffraction (XRD). The reduction behavior were examine by nonisothermal reduction up to 900 oC then continued with isothermal reduction at 900 oC for 45 min time under (40% v/v) carbon monoxide in nitrogen (CO in N2) atmosphere. The TPR signal clearly shows one peak attributed to formation of suboxide W18O49 (more) and WO2 (less) observed at 80 min. The reduction product was investigated by varying the holding reaction time. Based on the characterization of the reduction products by using XRD, it was found that, nonisothermal reduction of WO3 at temperature 900 oC partially converted to some W18O49 and WO2 phases. However, after increased the reaction holding time for 45 min, WO3 phases disappeared and converted to WO2 and W metal phases. It is obviously shows that by hold the reduction time could improve the reducibility of the sample oxide. Furthermore, it is suggested that reduction by using CO as reducing agent follows the consecutives steps WO3 → WO2.92 → W18O49 → WO2 → W.
Production of Stainless Steel 316L Foam with Different Solid Loading
Authors: Mat Noor Fazimah , Jamaludin Khairur Rijal , Ahmad Sufizar
Published: January 2016

Stainless steel foam has been used for various applications due to their advantages over other materials such as high corrosion resistance, easily availability, and low-cost as well as good mechanical properties. In this work, stainless foam was produced by using foam replication method with different solid loading of SS316L i.e 55 wt%, 60 wt%, 65 wt% and 70 wt% SS316L. The samples were sintered in a vacuum furnace at 1250°C. The sample microstructure was characterized by using scanning electron microscope (SEM) while the elemental component was analyzed by using Energy Dispersive X-ray (EDX). The Archimedes test has been conducted to determine the samples density and porosity. It was found that the best sample is SS316L foam with 65 wt% solid loading with the density and porosity of 1.85 g/cm3 and 76.84% respectively which are similar to the human bone. The sample also has open and interconnected pores.
Characterisation of WC-17Co and WC-9Ni HVOF Sprayed Cermet Coatings
Authors: Mohd Rabani Nur Amira , Kamdi Zakiah
Published: January 2016

Cemented tungsten carbides have been paid much attention due its better mechanical properties with excellent combination of hardness and toughness characteristics. The hard WC particles in the coating provide hardness and wear resistance, while the ductile binder such as Co and Ni contribute to toughness and strength. WC-17wt.% Co and WC-9wt.% Ni powders have been sprayed by the HVOF method to form coatings approximately 300μm and 150μm thick onto AISI 1018 steel substrate. Both coatings have been prepared and supplied by an external vendor. The coatings were examined using optical microscope (OM), scanning electron microscope (SEM), and X-Ray diffraction (XRD). The hardness of both coatings were also measured using Vickers micro-hardness tester. The microstructure of the coatings has been analyzed and found to consist of WC, brittle W2C phase, metallic W phase, and amorphous binder phase of Co and Ni. It is found that WC-Ni has a higher hardness value compared to WC-Co due to high porosity distribution.
Synthesis of Aluminium Hydroxide and Alumina by Hydrothermal and Solvothermal Methods
Authors: Meor Sulaiman Meor Yusoff , Mohamed Takip Khaironie , Sapiee Nur Aqilah , Zahari Ahmad Khairulikram
Published: January 2016

The paper describes some work done on the SEM and XRD characteristic studies of aluminium hydroxide and alumina synthesized by the solvothermal and hydrothermal methods. Hydrothermal process produced boehmite phase aluminium hydroxide while the solvothermal process produced gibbsite phase aluminium hydroxide. Transition reaction study by in-situ XRD shows that the gibbsite is transformed into boehmite before it is converted into alumina. This transformation stage involves a dissolution-recrystallization process. The SEM results show the changes in morphology of the crystals as a result of both these processes.
Sago Pith Waste Ash as a New Alternative Raw Materials from Agricultural Waste
Authors: Mohamed Rashid Mohamad Rohaidzat , Megat Johari Megat Azmi , Ahmad Zainal Arifin
Published: January 2016

This paper investigates the properties of Sago pith waste ash (SPWA) from agricultural waste using different calcination temperatures (500°C, 700°C and 1000°C). Chemical characteristic of SPWA was first investigated by using X-ray fluorescence (XRF) followed by XRD analysis as a verification of the mineralogical phases present in the SPWAs. Based on the analysis, the major compositions of SPWA are found to be CaO and SiO2 with other minor oxides such as MgO, Fe2O3 and Al2O3. Both CaO and SiO2 are very significant oxides that can be used as an alternative binder in the synthesis of ceramic materials and geopolymer. Moreover, the presence of these oxides are consistent for SPWA calcined from 500°C, 700°C and 1000°C. Phase transformation such as quartz, calcite and magnesite that can be found in 500°C and 700°C whilst new phases such as wollastonite, fayalite and cristobalite in 1000°C proved that SPWA beneficial to be used as a new material resources especially in the ceramic and geopolymer applications.
Chemical, Thermal and Phase Analysis of Malaysia’s Electric Arc Furnace (EAF) Slag Waste
Authors: Teo Pao Ter , Anasyida Abu Seman , Basu Projjal , Mohd Sharif Nurulakmal
Published: January 2016

This study aims to characterize and investigate properties of EAF slag waste obtained from Southern Steel Berhad, Penang (one of Malaysia’s largest steel makers), prior to its recycling into valuable products. Before characterization, lump form of the EAF slag was crushed into micron size powder. The properties investigated were loss of ignition (L.O.I.), chemical composition, leaching behavior, thermal properties and mineral phases present. Through XRF characterization, the chemical composition of the EAF slag was obtained. The slag was found to have extremely low L.O.I. (0.01 wt.%). Leaching test proved the slag is non-hazardous and safe to be handled. Meanwhile, thermal analysis (TGA) revealed the EAF slag is thermally stable and unlikely to decompose upon heating. Phase identification and quantification were performed by applying Rietveld refinement method. The EAF slag consisted of gehlenite (Al2O3.2CaO.SiO2 – 45.3 wt.%), larnite (2CaO.SiO2 – 21.0 wt.%), hematite (Fe2O3 – 13.4 wt.%) and wustite (FeO – 20.3 wt.%) mineral phases. The XRD profile fitted well with agreement indices of the refinement (Rwp: 6.658 and GOF: 2.588). The properties investigated in this study are expected to shed lights in evaluating the potential recycling of the EAF slag into various valuable products such as aggregate, brick, ceramic tile and cementing material.
Radioguided occult lesion localization and sentinel node and occult lesion localization in breast cancer: The future beckons
Authors: Jha Deepak , Deo S. V. S. , Malhotra Mandeep Singh
Published: January 2016

Wire Guided Localisation has been the traditional technique for occult breast lesions. However, ROLL has emerged as a safer alternative to WGL approach. ROLL provides an improvement on margin positive rates and offers better pain and cosmetic advantages to the patient combined with a shorter learning curves for both radiologists and surgeons. SNOLL adds to the advantages of the procedure by combining SLNB with ROLL hence offering an economic advantage. The use of ROLL as primary modality for occult lesion localisation is bound to increase with potential to replace WGL as the primary modality for such lesions.
Arm lymphedema after treatment of breast cancer: Etiology, diagnosis, and management
Authors: Goel Ashish , Agarwal Juhi , Mehta Sandeep , Kumar Kapil
Published: January 2016

Breast cancer related lymphedema (BCRL) is a chronic debilitating condition seen after treatment of breast cancer. The overall incidence varies from 20% to 56% in all patients treated for breast cancer. Every patient is at a lifelong risk for BCRL and the risk goes on increasing as the followup period increases. Locoregional treatment including surgery or radiotherapy is the most common risk factor for development of arm lymphedema. There are two phases of arm lymphedema. There is increased fluid accumulation in the fluid phase of lymphedema which later on goes into the solid phase where fat and fibrotic tissue is deposited in the subcutaneous tissue. The treatment of BCRL is a challenge both for the patient and the treating surgeon and it needs multidisciplinary team work to be successful. Non-surgical treatment modalities include complete decongestive therapy (CDT) and pneumatic compression therapy. Surgery for BCRL is usually undertaken as a salvage modality after failure of conservative approaches. The surgical spectrum for BCRL varies from extensive excisional operations which were commonly done in the past to newer methods like suction assisted protein lipectomy, lymphatic reconstruction and vascular lymph node transfer (VLNT) using super-microsurgical techniques. There is no consensus regarding the preference of one procedure over other due to lack of randomised control trials. It is however suggested to do lymphovenous anastomosis and complete decongestive therapy for early cases in fluid phase; while patients in the solid phase may be treated with a combination of liposuction with CDT or VLNT alone.
A Comparative Study on the Effect of Contrived vs. Authentic Texts on Iranian Intermediate EFL Learners’ Lexical Collocations Learning
Authors: Shabani Gholamhossein , Heidar Davood Mashhadi
Published: January 2016

The purpose of this research was to investigate the effects of two models of texts (contrived versus authentic texts) on Iranian intermediate EFL learners’ lexical collocation learning. The participants were sixty students majoring in English. They were students in the second semester of academic year 2015 who were selected through a proficiency test titled Comprehensive English Language Test (CELT), administered at the commencement of the study, the result of which showed that the two groups were homogeneous in terms of their language proficiency. They were divided into two equal comparison groups: The Authentic Text group (AT) and Contrived Text group (CT), either of which included thirty ones.  The quantitative data on the participants’ knowledge on lexical collocations were collected using a pre-planned pretest on lexical collocation, comprising forty multiple-choice-items. The pretest on lexical collocation went through a pilot study. The same version of the test of lexical collocation, with the rearrangement of some items, was administered to the both comparison groups after the completion of the treatment period for the AT group and placebo for the CT group. The analysis of the quantitative data was done using Independent Samples T-test and paired-samples T-test. The results of the Paired-samples T-test and Independent Samples T-test indicated that the AT group was significantly different from the control group; in other words, the AT group outperformed the CT group.  Pedagogical implications and suggestions for further research were included as well.
Diagnostic Accuracy of Epithelial Membrane Antigen for Malignant Effusions: A Meta-Analysis
Authors: Lin Wentao , Liu Xiaoxue , Cen Ying
Published: January 2016

Background and Objectives

Body cavity fluid examination sometimes presents a diagnostic challenge in cytology practice. This meta-analysis was undertaken to comprehensively assess the diagnostic potential of epithelial membrane antigen (EMA) in malignant effusions.

Materials and Methods

All relevant original articles about EMA in the diagnosis of malignant effusions published up to July 1, 2014 were retrieved. The overall sensitivity, specificity, positive and negative likelihood ratio, diagnostic odds ratio, and summary receiver operating characteristic (SROC) curve were pooled to evaluate the diagnostic value of EMA for malignant effusions using the Meta-Disc 1.4 and STATA 12.0 statistical software.

Results

Eleven studies met the inclusion criteria for the meta-analysis and the summary estimates for EMA in the diagnosis of malignant effusions were as follows: sensitivity 0.9 (95% CI 0.83-0.87), specificity 0.87 (95% CI 0.96-0.99), positive likelihood ratio 5.8 (95% CI 15.59-36.37), negative likelihood ratio 0.15 (95% CI 0.07-0.20) and diagnostic odds ratio 52.63 (95% CI 20.91-132.49). The SROC curve indicated that the maximum joint sensitivity and specificity (Q-value) was 0.88; the area under the curve was 0.94.

Conclusion

The present meta-analysis indicated that EMA may be a useful diagnostic tool with good sensitivity and specificity for differentiating malignant effusions from benign effusions.
Effectiveness of a Phonological Awareness Training for Arabic Disabled Reading Children: Insights on Metalinguistic Benefits
Authors: Layes Smail , Lalonde Robert , Rebai Mohamed
Published: January 2016

We examined the effects of a phonological awareness (PA) training program on word reading and pseudo-word decoding in dyslexic children reading the Arabic language (n=10; age mean= 129.74 months) in comparison to normal readers (n=10; age mean= 126.90 months) from grades 4 and 5. Particular attention was paid to phonological training of two metalinguistic reading related skills: morphological awareness (MA) and rapid automatized naming (RAN), underscored as main predictive metalinguistic factors in Arabic dyslexia (Layes, Lalonde, Mecheri, Rebaï, 2015). The PA training program focused on phoneme/syllable identification, phoneme matching, and word segmentation. The results indicate that the dyslexic group performed significantly better in all post-training measurements, increasing reading, phonological processing, and metalinguistic related skills, which indicates a strong relationship between these variables. The normal group only improved in MA production. These findings are discussed in terms of metalinguistic insights of reading gained through training in phonological awareness.
Libros, lectores y lectura en la literatura infantil y juvenil: Personajes analfabetas y “abyectos”
Authors: Arizpe Evelyn
Published: January 2016

La presencia de los libros, los lectores y la lectura en la literatura infantil y juvenil es más común de lo que pensamos y sin embargo, siguen siendo una minoría los libros donde aparece el acto de la lectura como algo más que una herramienta para obtener información.  La presencia o ausencia de las representaciones son indicadores de la forma en que la sociedad construye la relación entre los niños y jóvenes y la lectura. Este artículo analiza un grupo de textos donde aparece el tema de la alfabetización en cuanto a personajes que pueden considerarse como  “abyectos” según el trabajo de Julia Kristeva, en este caso, niños y jóvenes que viven en los márgenes de la sociedad, en la calle o en el tiradero. Las consecuencias de aprender a leer no siempre son las que nos imaginamos ya que tienen el poder de subvertir a las autoridades opresivas. El artículo se refiere también al Proyecto “Reading Fictions” dentro del cual se llevó a cabo este estudio.
“a. C y d. C”, de Francisco Font Acevedo. Un negro romance nacional
Authors: Fuentes Felipe Oliver
Published: January 2016

“a. C y d. C” presente en La Belleza Bruta del puertorriqueño Francisco Font Acevedo es una novela corta que combina los códigos característicos de la novela negra con el Romance Nacional. El objetivo de dicha hibridación narrativa consiste en mostrar la imposibilidad de construir un proyecto nacional homogéneo y unificador. Así, a través de una serie de personajes marginales y de un sugestivo conjunto de imágenes corporales violentas, “a. C y d. C” invierte el sentido integrador de los romances fundacionales decimonónicos desde el formato de la novela negra.
Reinaldo Arenas: una voz desde el margen y la resistencia
Authors: Casado Ana
Published: January 2016

Este artículo analiza el contexto social y cultural de la Cuba de los años sesenta y setenta, centrándose en el libro de Reinaldo Arenas Voluntad de vivir manifestándose, específicamente en aquellos poemas compuestos durante esa época. Acusado de escándalo público y de contrarrevolucionario, Arenas construyó su particular poética desobediente desde una perspectiva marginal y siempre liberadora. La escritura se convertiría en el contexto represivo y persecutorio del momento en el único espacio posible donde “ser”, resistir o pronunciarse, donde practicar una libertad anhelada y refutar verbalmente el encierro corporal concreto.
Dos narrativas de Mariel: muestrario de perdedores y suicidas
Authors: Matute Castro Arturo
Published: January 2016

Este trabajo aborda la función de la derrota en dos obras de autores de la emigración cubana de la década del ochenta, conocida como la generación del Mariel. Analizo el primer texto escrito por Reinaldo Arenas una vez que llega al exilio, “Final de un cuento” (1982), y publicado en el número inaugural de la revista Mariel (1983-1985). Comparo al héroe perdedor en el cuento de Arenas con el protagonista de la novela de Guillermo Rosales La casa de los náufragos (Boarding Home), de 1987. Considero que el significar la derrota como acto de resistencia frente a grupos políticos y culturales hegemónicos inscribe a los autores del Mariel dentro de un corpus de literatura latinoamericana migrante del cual tradicionalmente se les ha excluido.
On Truth and Opacity. Symbolic Translation and Legibility in Contemporary Text-Based Cuban Art
Authors: Garrido Castellano Carlos
Published: January 2016

This paper examines text-based artworks that employ symbolic translations as a way of analyzing the discursive constrains regulating the Cuban public sphere. Through a revision of artistic projects that turn to translation and intend to provoke the spectator’s active engagement, I seek to understand which possibilities are opened by translation in order to escape the burdens of representation and commoditization shaping contemporary Cuban art. I argue that the encouragement of direct experience could be framed as that possible alternative. The potential attributed to experience and practicality, nevertheless, cannot be directly deduced from the artist’s intentions, being contingent ultimately of how each project works.
Autorretrato en tinta
Authors: Vilches Norat Vanessa
Published: January 2016

Cuento de ficción
Fuego en la capital
Authors: Kobbé Montague
Published: January 2016

Cuento de ficción de Montague Kobbé
Introducción. Sujetos y subjetividades en el Caribe hispano: lecturas y escrituras desde el siglo XXI
Authors: Vera-Rojas María Teresa , Bustamante Fernanda
Published: January 2016

Introducción del dossier "Sujetos y subjetividades en el Caribe Hispano" (vol. 12, invierno de 2015)
Somos islas hechas de infinidad de fronteras. Entrevista a Rey Andújar
Authors: Bustamante Fernanda
Published: January 2016

Entrevista realizada al escritor dominicano Rey Andújar. Ganador del premio ALBA narrativa 2015.
Studying the electrochemical deposition process of molybdenum from aqueous solution of molybdate ions
Authors: Cafarova Samira Fikret , Aliyev Akif Shikhan , Elrouby Mahmoud , Soltanova Nsh , Tagiyev Dilgam Babir
Published: January 2016

In this study, the tracing of the electroreduction process of molybdate ions in aqueous media at different conditions is achieved for obtaining molybdenum metal in a simple and easy way. The kinetics and the mechanism of the electroreduction of molybdate ions are studied using cathodic polarization technique. It is observed that, the speed of the electroreduction process depends on the speed of the change of the cathodic potential sweep as well as on the temperature of the electrodeposition bath. Moreover, it is observed that, at the potential range from the stationary potential (Est = 0.25V) to −0.7 V, the electroreduction of molybdate ions occurs into two steps. Moreover it is observed that, after −0.7 V the electroreduction process of molybdate is accompanying with evolution of hydrogen.
Selection for Preservation
Authors: Teper Jennifer Hain
Published: January 2016

Library preservation programs are at the precipice of transformation. With the increasing availability of digitized content, and the development of shared print repositories, our perceived obligation to the preservation of individual print copies at an institutional level is shifting to a more shared model. Library preservation professionals must now determine how this is influencing our day to day practices. This paper reviews the data collected from a 2012 survey and interprets that data to show how the availability of digital surrogates, libraries’ increasing consideration of shared print holdings, and the perceived value of scarcely held content are all influencing preservation selection.
Human Cortical Neural Stem Cells Expressing Insulin-Like Growth Factor-I: A Novel Cellular Therapy for Alzheimer's Disease
Authors: McGinley Lisa M. , Sims Erika , Lunn J. Simon , Kashlan Osama N. , Chen Kevin S. , Bruno Elizabeth S. , Pacut Crystal M. , Hazel Tom , Johe Karl , Sakowski Stacey A. , Feldman Eva L.
Published: January 2016

Alzheimer's disease (AD) is the most prevalent age-related neurodegenerative disorder and a leading cause of dementia. Current treatment fails to modify underlying disease pathologies and very little progress has been made to develop effective drug treatments. Cellular therapies impact disease by multiple mechanisms, providing increased efficacy compared with traditional single-target approaches. In amyotrophic lateral sclerosis, we have shown that transplanted spinal neural stem cells (NSCs) integrate into the spinal cord, form synapses with the host, improve inflammation, and reduce disease-associated pathologies. Our current goal is to develop a similar “best in class” cellular therapy for AD. Here, we characterize a novel human cortex-derived NSC line modified to express insulin-like growth factor-I (IGF-I), HK532-IGF-I. Because IGF-I promotes neurogenesis and synaptogenesis in vivo, this enhanced NSC line offers additional environmental enrichment, enhanced neuroprotection, and a multifaceted approach to treating complex AD pathologies. We show that autocrine IGF-I production does not impact the cell secretome or normal cellular functions, including proliferation, migration, or maintenance of progenitor status. However, HK532-IGF-I cells preferentially differentiate into gamma-aminobutyric acid-ergic neurons, a subtype dysregulated in AD; produce increased vascular endothelial growth factor levels; and display an increased neuroprotective capacity in vitro. We also demonstrate that HK532-IGF-I cells survive peri-hippocampal transplantation in a murine AD model and exhibit long-term persistence in targeted brain areas. In conclusion, we believe that harnessing the benefits of cellular and IGF-I therapies together will provide the optimal therapeutic benefit to patients, and our findings support further preclinical development of HK532-IGF-I cells into a disease-modifying intervention for AD.

Significance

There is no cure for Alzheimer's disease (AD) and no means of prevention. Current drug treatments temporarily slow dementia symptoms but ultimately fail to alter disease course. Given the prevalence of AD and an increasingly aging population, alternative therapeutic strategies are necessary. Cellular therapies impact disease by multiple mechanisms, providing increased efficacy compared with traditional, single-target drug discovery approaches. This study describes a novel enhanced human stem cell line that produces increased amounts of growth factors beneficial to the disease environment. Findings support further development into a potentially safe and clinically translatable cellular therapy for patients with AD.
El Smartphone en los procesos de enseñanza-aprendizaje-evaluación en Educación Superior. Percepciones de docentes y estudiantes.
Authors: González-Fernández Natalia , Salcines-Talledo Irina
Published: January 2016

El dispositivo móvil que mayor acogida está teniendo en la actualidad es el Smartphone, simbolizando la revolución del Internet móvil. Aunque la incidencia de las tecnologías y formas de comunicación emergentes en la sociedad es innegable, en el ámbito educativo, supone un reto. Por ello, los objetivos de este trabajo se centran en detectar la importancia otorgada al Smartphone como herramienta al servicio de los procesos de enseñanza, aprendizaje y evaluación, por docentes y discentes de Educación Superior y, conocer los beneficios y dificultades apreciadas por el profesorado y alumnado universitario, sobre la introducción del Smartphone en los procesos de enseñanza, aprendizaje y evaluación. Para ello se ha diseñado, validado e implementado herramientas de recogida de información cuantitativas y cualitativas, aplicando dos cuestionarios, uno destinado a docentes (n=311) y otro a estudiantes (n=483) y, dos Grupos Focales con estudiantes (n=6) y profesores (n=6). Los resultados muestran que, a pesar de la baja implementación pedagógica del Smartphone, docentes y estudiantes perciben más ventajas que dificultades respecto a su introducción en las aulas universitarias.
Relación entre origen social e inserción laboral de los graduados universitarios
Authors: Fachelli Sandra , Navarro-Cendejas José
Published: January 2016

Este artículo tiene dos objetivos. En primer lugar, queremos analizar si el peso del origen social de los graduados universitarios influye en la inserción laboral, tomando como indicador los ingresos que obtienen los titulados que trabajan, cuando controlamos la titulación obtenida. En segundo lugar, intentamos observar si los graduados universitarios provenientes de orígenes sociales más desfavorecidos se encuentran más desocupados y más inactivos que los provenientes de hogares con más recursos. Para tal fin analizamos a los titulados que egresaron de universidades públicas catalanas en el curso 2006-2007, entrevistados por la “Agencia Catalana per a la Qualitat del Sistema Universitari de Catalunya” (AQU Catalunya) en el primer trimestre de 2011. La metodología utilizada se basa en técnicas estadísticas bivariadas (tablas de contingencia) y análisis multivariado (regresión logística binomial). Los resultados obtenidos en la presente contribución nos obligan a reformular las hipótesis de partida, pues los hallazgos muestran que, aun tomando en cuenta la titulación, no se observa una influencia significativa del origen social en la inserción laboral de esta cohorte concreta de graduados universitarios
Sexual risk behaviour among people living with HIV according to the biomedical risk of transmission: results from the ANRS‐VESPA2 survey
Authors: Suzan‐Monti Marie , Lorente Nicolas , Demoulin Baptiste , Marcellin Fabienne , Préau Marie , Dray‐Spira Rosemary , Lert France , Spire Bruno ,   the ANRS‐VESPA2 Study Group
Published: January 2016

Introduction

People living with HIV (PLHIV) on antiretroviral therapy (ART), with sustained undetectable viral load (sUVL) and no history of sexually transmitted infections for at least six months, are considered to have a low risk of HIV transmission (LRT). We aimed to characterize, in a representative sample of French PLHIV, the sexual behaviour of LRT PLHIV compared with non‐LRT PLHIV.

Methods

The cross‐sectional ANRS‐VESPA2 survey was conducted on adult PLHIV attending French hospitals in 2011. The LRT PLHIV group included participants with sUVL and no sexually transmitted infection for at least 12 months. Socio‐behavioural and medical data were collected. Chi‐square tests helped compare sexual risk indicators between LRT and non‐LRT PLHIV. The survey's retrospective nature allowed us to perform complementary category‐based analyses of LRT PLHIV according to whether they had sUVL for at least 18, 24 or 36 months in three socio‐epidemiological groups: men who have sex with men (MSM), other men and women.

Results

Analysis included 2638 PLHIV diagnosed >12 months with available viral load data. The proportion of LRT PLHIV varied from 58% (≥12 months sUVL) to 38% (≥36 months sUVL). Irrespective of sUVL duration, we found the following: 1) LRT men (MSM and other men) were more likely to report having no sexual partner than their non‐LRT counterparts. Among men having sexual partners in the previous 12 months, no significant difference was seen between LRT and non‐LRT men in the number of sexual partners. LRT women were less likely to report having more than one sexual partner than non‐LRT women; 2) LRT MSM were more likely to report being in sexually inactive couples than their non‐LRT counterparts; 3) among sexually active participants, no difference was observed between LRT and non‐LRT PLHIV concerning condom use with their serodiscordant steady partner or with their most recent casual sexual partners.

Conclusions

LRT PLHIV with sUVL ≥12 months did not report more sexual risk behaviours than their non‐LRT counterparts. Because the same result was obtained for those having a sUVL ≥36 months, the hypothesis of increased sexual risk behaviour over time in PLHIV meeting non‐transmission biomedical criteria is not supported.
Structural basis of nucleic-acid recognition and double-strand unwinding by the essential neuronal protein Pur-alpha
Authors: Weber Janine , Bao Han , Hartlmüller Christoph , Wang Zhiqin , Windhager Almut , Janowski Robert , Madl Tobias , Jin Peng , Niessing Dierk
Published: January 2016

The neuronal DNA-/RNA-binding protein Pur-alpha is a transcription regulator and core factor for mRNA localization. Pur-alpha-deficient mice die after birth with pleiotropic neuronal defects. Here, we report the crystal structure of the DNA-/RNA-binding domain of Pur-alpha in complex with ssDNA. It reveals base-specific recognition and offers a molecular explanation for the effect of point mutations in the 5q31.3 microdeletion syndrome. Consistent with the crystal structure, biochemical and NMR data indicate that Pur-alpha binds DNA and RNA in the same way, suggesting binding modes for tri- and hexanucleotide-repeat RNAs in two neurodegenerative RNAopathies. Additionally, structure-based in vitro experiments resolved the molecular mechanism of Pur-alpha's unwindase activity. Complementing in vivo analyses in Drosophila demonstrated the importance of a highly conserved phenylalanine for Pur-alpha's unwinding and neuroprotective function. By uncovering the molecular mechanisms of nucleic-acid binding, this study contributes to understanding the cellular role of Pur-alpha and its implications in neurodegenerative diseases.
Atomic structure of the 26S proteasome lid reveals the mechanism of deubiquitinase inhibition
Authors: Dambacher Corey M , Worden Evan J , Herzik Mark A , Martin Andreas , Lander Gabriel C
Published: January 2016

The 26S proteasome is responsible for the selective, ATP-dependent degradation of polyubiquitinated cellular proteins. Removal of ubiquitin chains from targeted substrates at the proteasome is a prerequisite for substrate processing and is accomplished by Rpn11, a deubiquitinase within the ‘lid’ sub-complex. Prior to the lid’s incorporation into the proteasome, Rpn11 deubiquitinase activity is inhibited to prevent unwarranted deubiquitination of polyubiquitinated proteins. Here we present the atomic model of the isolated lid sub-complex, as determined by cryo-electron microscopy at 3.5 Å resolution, revealing how Rpn11 is inhibited through its interaction with a neighboring lid subunit, Rpn5. Through mutagenesis of specific residues, we describe the network of interactions that are required to stabilize this inhibited state. These results provide significant insight into the intricate mechanisms of proteasome assembly, outlining the substantial conformational rearrangements that occur during incorporation of the lid into the 26S holoenzyme, which ultimately activates the deubiquitinase for substrate degradation.
Fabrication of all-solid AsSe2–As2S5 microstructured optical fiber with two zero-dispersion wavelengths for generation of mid-infrared dispersive waves
Authors: Cheng Tonglei , Tuan Tong Hoang , Liu Lai , Xue Xiaojie , Matsumoto Morio , Tezuka Hiroshige , Suzuki Takenobu , Ohishi Yasutake
Published: January 2016

We design and fabricate an all-solid chalcogenide microstructured optical fiber (MOF) with four rods in the cladding, in order to generate mid-infrared (MIR) dispersive waves (DWs). The high-index background is made of AsSe2 glass, and the four low-index rods are made of As2S5 glass. This MOF has two zero-dispersive wavelengths: ∼3,720 and 4,230 nm. The propagation loss is ∼1.9 dB/m at 2,000 nm, and the nonlinear coefficient is ∼4 × 103 km−1 W−1 at 3,000 nm. Using a pulse of ∼80 MHz and ∼200 fs emitted from an optical parametric oscillator as the pump source, the resulting MIR DWs are investigated at different pump wavelengths.
Annealing of an AlN buffer layer in N2–CO for growth of a high-quality AlN film on sapphire
Authors: Miyake Hideto , Nishio Gou , Suzuki Shuhei , Hiramatsu Kazumasa , Fukuyama Hiroyuki , Kaur Jesbains , Kuwano Noriyuki
Published: January 2016

The annealing of an AlN buffer layer in a carbon-saturated N2–CO gas on a sapphire substrate was investigated. The crystal quality of the buffer layer was significantly improved by annealing at 1650–1700 °C. An AlN buffer layer with a thickness of 300 nm was grown by metalorganic vapor phase epitaxy (MOVPE), and was annealed at 1700 °C for 1 h. We fabricated a 2-µm-thick AlN layer on the annealed AlN buffer layer by MOVPE. The full widths at half maximum of the (0002)- and (

)-plane X-ray rocking curves were 16 and 154 arcsec, respectively, and the threading dislocation density was 4.7 × 108 cm−2.