bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization of 316L Stainless Steel Foams for Biomedical Applications
Authors: Abdullah Zulaikha , Ahmad Sufizar , Mahammad Rafter Murni Faridah
Published: January 2016

Metal foam is the cellular structures that made from metal and have pores in their structures. Metal foam also known as the porous metals, which express that the structure has a large volume of porosities with the value of up to 0.98 or 0.99. Porous 316L stainless steel was fabricated by powder metallurgy route with the composition of the SS316L metal powder as metallic material, polyethylene glycol (PEG) and Carbamide as the space holder. The powders were mixed in a ball mill at 60 rpm for 10 minutes and the mixtures were put into the mold for the pressing. The samples were uniaxially pressed at 3 tons and heat treated by using box furnace at 870 °C. There are several tests that have been conducted in order to characterize the physical properties of metal foam such as density and porosity testing, and the morphological testing (Scanning Electron Microscopy (SEM)). The results show that the composition of 85 wt% SS316L of metal foam show high in porosity which suitable for implants application.
Compression Strength of Gellan Gum Hydrogel Incorporated with Organo-Montmorillonite and Cloisite 15A
Authors: Syazwani Mohd Saffawati , Abdullah Mohd Aidil Adhha , Mat Amin Khairul Anuar
Published: January 2016

The uniformly cross-linked gellan gum hydrogel with sodium montmorillonite (Na-MMT), organo-montmorillonite (CTAB-MMT) and Cloisite 15A were successfully prepared. The compression performances of the hydrogels were investigated. The results show that the GG hydrogels containing Cloisite 15A required smallest volume to achieve optimum compression stress, modulus and compression strain at 5% (w/w) compared to both Na-MMT and CTAB-MMT at 10% (w/w), respectively. The decrease in compression performances of gellan gum hydrogel at higher concentration containing those clays could be due to agglomeration process which created the entangled structure and bring up the brittleness of hydrogel properties. Overall, the presence of the clays significantly improved the mechanical performances of gellan gum hydrogels which beneficial to be used in tissue engineering.
Optimization and Characterization of Anatase Formed on Anodized Titanium in Phosphoric Acid
Authors: Saleh Saleh S. , Abdullah Hasan Zuhudi
Published: January 2016

Titanium (Ti) is widely used in dental and orthopedic implants because of its good biocombatibility and high corrosion resistance. Titanium oxide (TiO2) has shown to exhibit strong physicochemical bonding between Ti implant and living bone because of its ability to induce bone-like apatite in a body environment. Ti is always coated by an oxide surface layer of 1.5-10 nm thickness. TiO2 crystalline structures; anatase and rutile present several distinctive features, such as photocatalytic behaviour, superhydrophilicity and biocompatible properties. Anodic oxidation is used to modify the surface of pure titanium in a phosphuric acid electrolyte in order to maximize and characterize the TiO2 anatase crystalline phase. In the present work, thick films of the anatase polymorph of TiO2 were formed on commercially pure Ti foil under potentials 200 V-350 V at current densities 40 and 60 mA/cm2 for 10 min. Multiple characterization techniques were used. Glancing angle X-ray diffraction (GAXRD) is used to obtain crystalline phases, field emission scanning electron microscope (FESEM) is used to obtain surface images and water contact angle (WCA) is used to obtain the wettability of the oxide surface. According to GAXRD results the intensity of the major peak increased with increasing applied voltage and current density while decrease with molar concentration. This means that the amount and/or crystallinity of anatase are/is influenced with these parameters. The coated oxides obtained small amount of anatase is comparing to films anodized in H2SO4 electrolyte. Which confirm that slower crystallization in H3PO4 than in H2SO4. FESEM images obtained that as the voltage increased, the film breaks down locally and results in a porous surface. The porosity and the pore size increase with the increasing voltage. The pore size diameter at 300V for 0.3 M can reach up to 1μm. As for WCA results the coated samples at higher voltages (250 V, 300 V and 350 V) and molar concentration 0.3 M have shown more hydrophilic surface, with sample anodized at 350 V at 0.3 M have the lowest contact angle, thus the highest surface energy. While samples anodized at 200 V voltage observed more hydrophobic surface with sample anodized at 200 V at 0.1 M have the lower wettability, thus the lowest surface energy.
Ba0.5Sr0.5Co0.8Fe0.2-SDC Carbonate Composite Cathode for Low-Temperature SOFCs
Authors: Agun Linda , Ahmad Shah Mohamed Hakim , Ahmad Sufizar , Rahman Hamimah Abdul
Published: January 2016

The composite cathode Ba0.5Sr0.5Co0.8Fe0.2 (BSCF)–samarium-doped ceria carbonate (SDCc) was reviewed based on different (Li/Na)2 carbonate molarities (67:33, 62:38, and 53:47 (mol.%)). Effects of (Li/Na)2 carbonate on BSCF was studied in terms of chemical, thermal, and physical properties. Composite-cathode powders were prepared using high-energy ball milling (HEBM) and calcined at 750 °C for 2 h before uniaxial pressing to form a pellets. Afterwards, the pellets were sintered at 600 °C for 90 min to obtain porous composite-cathode pellets. Powders behaviors were examined based on particle size and thermal expansion by using Image J software, field-emission scanning electron microscopy (FESEM) and dilatometry respectively. Cross-section morphology of the pellets were characterised by FESEM to examine grain positions and by the Archimedes principle to identify the porosity, respectively. The quantitative elements for the BSCF-SDCc pellet were identified using energy-dispersive spectroscopy (EDS). HEBM enabled the cathode to achieve a nanocomposite state. Cathode cells obtained became porous when porosity values were between 26% and 30%. These results showed that BSCF–SDCc has high potential for low-temperature solid oxide fuel cell (LT-SOFC) applications.
Morphology, Thermal and Chemical Properties of Nanocrystalline Cellulose (NCC) Hydrolyzed from Banana Stem
Authors: Kasa Siti Norbaya , OMAR MOHD FIRDAUS , Nizam Ismarul
Published: January 2016

Banana stem (BS) was used as the natural cellulose source. It must undergo an alkali treatment and bleaching process before continuing with an acid hydrolysis. Then, the Nanocrystalline cellulose (NCC) was synthesized via acid hydrolysis with four different concentrations of sulfuric acid (H2SO4) at 50 %, 52 %, 54 % and 56 % respectively at 50 0C for 1 hour. The influence of acid concentration of morphology, thermal and chemical properties of the NCC was studied in this project. The morphology dimension of the NCC was determined by using field emission scanning electron microscope (FESEM) and thermal stability of the NCC was determined by using thermal gravimetric analysis (TGA). Chemical composition and structural analysis were measured by using Fourier transform infrared (FT-IR) and X-ray diffraction (XRD).
Phase Evolution of Yttrium Iron Garnet (YIG) Made by Solid State Sintering: Particle Size Effect
Authors: Wan Ali Wan Fahmin Faiz , Abdullah Norazharuddin Shah , Ain Mohd Fadzil , Ahmad Zainal Arifin
Published: January 2016

The phase evolution of yttrium iron garnet (YIG) during reaction 3Y2O3-5Fe2O3 was investigated by modifying Fe2O3 particle sizes (FPS). Five different sizes of Fe2O3, (d50) are used to prepare YIG powder. Solid state reaction (SSR) was applied at 1200 °C in order to gain insight on the effect of FPS towards the YIG formation. Rietveld refinement method was used to quantify the amount of YIG yielded (%). Larger FPS (> 50 μm) initiates only 5Fe2O3 + 3Y2O3 à 3YFeO3 + Fe2O3 + Y3Fe5O12.. However, when the fine FPS (5 μm) is used, the reaction pathway was changed into 5Fe2O3 + 3Y2O3 à 6YFeO3 + 2Fe2O3 à 2Y3Fe5O12. These behaviors is explained that the smaller FPS consumed quickly to form YIG due to the smaller particle distance between Fe2O3 and Y2O3. This shall be leading to higher reaction rates (mass-transfer kinetics).
Effects of Neutron and Electron Irradiation on 4H-SiC Diodes
Authors: Abdullah Yusof , Hak Cik Rohaida Che , Megat Ahmad Megat Harun Al Rashid , Hasbullah Nurul Fadzlin , Yusof Mohd Reusmaazran , Mahat Sarimah , Ee Abdullah Nurhaslinda
Published: January 2016

4H-SiC Schottky barrier diodes (SBDs) were irradiated to neutron fluence of 3.55 x1016 cm-2 and 6.6 x 1015 cm-2 (15,000 kGy) electrons respectively. In general, characterization of the irradiated samples show that the current characteristics of the diodes decreased. The performance of Schottky gate contact is less for electron irradiated sample compared to neutron irradiated sample. The d-spacing, crystallite sizes and lattice strains were calculated from X-ray diffraction (XRD) measurements. SiC Schottky interface damage and radiation defects, as observed in atomic force microscopy (AFM) topography and scanning electron microscope (SEM) morphology images is possibly the main reason for this reduction in performance.
Physical Properties of 316L Stainless Steel (SS316L) Foam with Different Composition by Using Compaction Method
Authors: Mahammad Rafter Murni Faridah , Ahmad Sufizar , Ibrahim Rosdi
Published: January 2016

Nowadays, the 316L stainless steel metal foams (SS316L) have acknowledged important attention in various fields and are required to be used as engineering materials including heat exchange, sound absorption, filtration and others. So, in this study the production of SS316L foams using different composition through compaction method by using a starch powder as space holder was studied. The range of selected composition of SS316L that obtained is between 50 wt% to 60 wt% while the remaining percentages are space holder and binder. The SS316L compact is prepared by mixing SS316L alloy powder, starch powder, and Polyethylene Glycol (PEG). Then, the mixture is compact into a mould under 8 tonnes of controlled pressure using hydraulic press machine. This is later sintered in a vacuum furnace. The sintered SS316L foams were characterised using a Scanning Electron Microscopy (SEM) analysis. Then, the physical properties of SS316L foam was also analysed by Archimedes method that includes porosity and bulk density test. As a result, the sample with 60 wt% were produced a good and finer pores and struts. Meanwhile, for that sample the percentage of porosity and bulk density are 0.19% and 7.44 g/cm3, respectively.
Effects of Soil Physical Properties to the Corrosion of Underground Pipelines
Authors: Ahmad Saupi Siti Rumaisha , Abdul Haris Nur Ain Haris , Masri Mohamad Najmi , Sulaiman Muhammad Azwadi , Abu Bakar Mohamad Bashree , Mohamad Amini Mohd Hazim , Mohamed Mazlan , Nik Yusuf Nik Alnur Auli
Published: January 2016

Corrosion of metals in soil be able to change from comparatively fast material loss to insignificant effects, depending on soil environment. Corrosion is a process of deterioration of metal surfaces degraded into another compound. Soil is one of the medium known to have constituted to corrosion of metals. The soil creates an environment for the corrosion to react. The buried pipelines are exposed to the soil that may experience corrosion attack. The study of the soil as corrosion environment is important to mitigate the problem due to the environment and economy. There are factors that contribute to the corrosion process. This study concentrates on corrosion properties that expose to soil environment particularly underground pipelines. The mild steel coupons taken from actual pipelines, stimulating and analyzing the physic-chemical characteristics of the soil environment. The soil is sandy clay in natural. A total summed index of 2 numerical scale, thus, indicates that the soil tested was mildly to non-corrosive. The corrosion rate increase with increasing of moisture content and pH value. The observations on the coupon surface also did in order to study the morphology.
Studies on Adsorption-Desorption of CO2 by Long Chain Fatty Amine Supported on SiO2
Authors: Abu Tahari Maratun Najiha , Hakim Azizul , Marliza Tengku Sharifah , Wan Isahak Wan Nor Roslam , Mohamed Hisham Mohamed Wahab , Yarmo Mohd Ambar
Published: January 2016

The capture of carbon dioxide (CO2) molecules was achieved by utilizing impregnated long chain fatty amine solid sorbents. The long chain fatty amine impregnated on these solid substrates was octadecylamine (ODA) to improve CO2 adsorption-desorption capacity. The amine-loaded samples were characterized using nitrogen, N2 adsorption-desorption isotherm of Brunauer-Emmet-Teller (BET) and thermogravimetry analyzer (TGA). The prepared 25 wt % ODA/SiO2 exhibit acceptable CO2 capture capacities of 2.45 wt % CO2/adsorbent at 25 °C by using CO2 adsorption-desorption isotherm. TG profile shows that the solid sorbents able to adsorb and desorb CO2 in equivalent amount.
Synthesis of Polymethylvinylsiloxane from Several Silicon Compounds Followed by FTIR and NMR Techniques
Authors: Jikan Suzi Salwah , Danlami Shehu Isah , Badarulzaman Nur Azam
Published: January 2016

Polymethylvinylsiloxane (PMVS) were prepared by pre-hydrolysis/condensation of several silicon compounds: methylvinydichlorosilane (MVDCS) and dimethyldichlorosilane (DMDCS) followed by catalysis equilibrium copolymerization by dibutyltin dilaurate (DBTDL). All manipulations in the experiments were performed under ambient condition. The PMVS were characterized by Fourier transform infrared spectroscopy (FTIR). This method has provided information about the structure of the polymer. The 13C NMR techniques give two sets of carbons at 1.77 ppm and 136.0 ppm consist of signals from carbons of both ligand groups, whereas 29Si NMR signals of the-22.49 ppm and-35.98 ppm region are due to silicon sites bearing the methyl and vinyl ligand groups; the 29Si signals of the - 109 ppm region are due to silicon sites without ligand groups attached.Keywords: Polymethylvinylsiloxane, copolymerization, NMR
In Situ XRD Study of Zirconia Phase Transformation Produced from Chemical and Mineral Processes
Authors: Meor Sulaiman Meor Yusoff , Mohamed Takip Khaironie , Zahari Ahmad Khairulikram
Published: January 2016

The high temperature phase transition of zirconia produced from commercial zirconyl chloride chemical was compared with that produced from a Malaysian zircon mineral. Zirconyl chloride was produced from zircon by using the hydrothermal fusion method. Initial XRD diffractogram of these samples at room temperature show that they are of amorphous structure. High temperature XRD studies was then performed on these samples; heated up to 1500°C. The XRD diffractograms shows that the crystalline structure of tetragonal zirconia was first observed and the monoclinic zirconia becomes more visible at higher heating temperature.
The Hardness Properties of Porcelain with Substitution of Quartz by Rice Husk Ash at Different Soaking Time
Authors: Noh Mohamad Zaky , Hassan Uman , Ahmad Zainal Arifin
Published: January 2016

An extensive studied has been done with rice husk ash (RHA) as a substitute element for quartz to produce porcelain. Rice husk (RH) was treated with HCL. The treated RH was subjected to calcinations at 700°C for six hours, then subjected to the XRF analysis. The composition of RHA and porcelain powder were mixed using a ball mill for 1.5 hours, then was pressed into pellets at a pressure of 91 MPa. The pellets were sintered at a temperature of 1200°C for 1 hour, 2 hours and 3 hours soaking time, at a heating rate of 5°C per minute. The bulk density and Vickers hardness were measured. At the soaking time of 2 hours, the maximum density and hardness were achieved at 2.45 g/cm3 and 1052 HV respectively. SEM analysis reveals a typical sequence of densification enhancement with the increasing of soaking time.
Waste Banana Peel and its Potentialization in Agricultural Applications: Morphology Overview
Authors: Nik Yusuf Nik Alnur Auli , Rosly Ernie Surianiy , Mohamed Mazlan , Abu Bakar Mohamad Bashree , Yusoff Mahani , Sulaiman Muhammad Azwadi , Ahmad Muhammad Iqbal
Published: January 2016

The reserach is focused on the resistance of bio-polymer thin film to bio-degradation in compost soil from renewable resources based on waste banana peel and waste egg shell in polymer matrix. The combination of waste banana peel and waste egg shell in producing of bio-mulching film is a new inovation in agricultural industry . Bio-mulching film is a biodegradable plastics films that can help in increasing the moisture content of soil and improving the soil ingredients in order to make the plants grow well. The thin film is produced by using the waste banana banana peelas the reinforcement fiber, eggshell as filler and epoxy resin as matrix. The thickness of thin film was in between 0.10 mm to 0.15 mm. The epoxy/waste banana banana peelwith eggshell (EWE) 10%, were affected by bio-degradation in soi burial test where the occurances of surface damages, which in turn enhances the degradation of physical properties.
Development of α-Fe2O3 as Adsorbent and its Effect on CO2 Capture
Authors: Hakim Azizul , Marliza Tengku Sharifah , Abu Tahari Maratun Najiha , Yusop Muhammad Rahimi , Mohamed Hisham Mohamed Wahab , Yarmo Mohd Ambar
Published: January 2016

Iron oxide (α-Fe2O3) as adsorbent was no longer new in CO2 adsorption studies. However, its contributions in the industry still in limited wherein lack of convincing results of quantifying of adsorbed CO2. This work presents an analysis for α-Fe2O3 was prepared by simple mixing method with identified the adsorption capacity that applied in CO2 capture. The synthesized α-Fe2O3 from different concentrations of precursor were analyzed using XRD, N2 adsorption-desorption isotherms with BET and BJH method, TEM, FTIR, CO2 adsorption at 298 K, CO2-TPD and TGA-DTG. It was noted that 2M concentration of precursor (s2M) with highest crystallite peaks shows highest surface area among all samples which indicative of well generated pores. The different concentration of precursor was found generated more porosity rather than particle size according to TEM micrograph. The sphere shape crystallite particle with high surface area (50.5 m2/g) and porosity were desirable properties in CO2 adsorption. Consequently, physically adsorbed CO2 with adsorption at 298 K was highest with adsorption capacity of at 17.0 mgCO2/gadsorbent. Finally, chemically adsorbed CO2 was successfully identified from CO2–TPD analysis with adsorption capacity of 0.19 mgCO2/gadsorbent and 1.31 mgCO2/gadsorbent at maximum desorption temperature of 375 °C and 749 °C respectively.
Potential of Fabricated Light Foamed Concrete in Reducing Radon from Building Material
Authors: Saidi Syahrul Affandi , Jaafar Mohamad Suhaimi , Razab Mohammad Khairul Azhar Abdul , Mat Rasat Mohammad Sukhairi , Ahmad Muhammad Iqbal , Mohamed Mazlan , Mamat Sarizam , Hussin Hamzah
Published: January 2016

Three of Light Foamed Concrete (LFC) have been obtain by using different formula of Cement:Aggregates. The brick was locate into a closed Perspex box and the net of 222Rn concentration level have been measured for 5 consecutive days. The results show the LFC 3 has produced the lowest of net 222Rn concentration level in air, followed by LFC 2 and LFC 1, respectively. The result also show the 222Rn concentration level have been influenced by the temperature and relative humidity in air.
Synthesis and Structural Characterization of La0.8Sr0.2MO3 (M=Mn, Fe, Co and Cr) Solid Ionic Material for Catalyst Application
Authors: Azri Aziz Muhammad Nor , Johar Banjuraizah , Khor Shing Fhan , Ahmad Zainal Arifin
Published: January 2016

La0.8Sr0.2MO3+δ, (M=Mn, Fe, Cr, Co) ceramics were prepared by using solid state reaction method. All raw materials were mixed and ground using mortar. Homogenized powders were calcined at 900°C for three hour followed by grounding and uniaxial pressed at 100MPa. Compacted pellets were further pressed using cold isostatic pressing machine at 2600kg/m.s and sintered at 1300°C with heating rate 5°C/min for 4 hour. Crystal structure and phase transformation of sintered samples were obtained using X-ray diffraction. Density and porosity are measured by using Archimedes principle. The morphology of sintered samples is observed using scanning electron microscopy, while elemental analysis using the EDX.
Effect of Glass Addition on the Properties of CaCu3Ti4O12 Ceramics
Authors: Mohamed Julie Juliewatty , Ab Rahman Mohd Fariz , Ain Mohd Fadzil , Ahmad Zainal Arifin
Published: January 2016

The effect of glass addition on the properties of CaCu3Ti4O12 (CCTO) ceramics was studied. CCTO ceramics with BaO-SrO-Nb2O5-B2O3-SiO2 (BSNBS) glass additive were prepared using solid state reaction method. The raw materials of CCTO and BSNBS were wet mixed separately for 24 hours, dried overnight and subsequently the BSNBS powders was melted at 1450°C for 2 hours while CCTO powders was calcined at 900°C for 12 hours. BSNBS glass then was grinded to form a fine powders. Different weight percentages of BSNBS powder were added into CCTO and the powders were wet mixed at 24 hours. The mixtures were dried, compacted at 250 MPa and then sintered at 1050°C for 10 hours. X-Ray Diffractometer (XRD) analysis showed the formation of CCTO phase for all sintered samples while secondary phase of CuO phase was identified for sintered BSNBS 1.0 sample. Observation on Scanning Electron Microscopy (SEM) micrographs showed abnormal grain growth was seen in CCTO sample and grain size of the samples become finer with increasing the concentration glass addition. CCTO sample obtained the highest dielectric constant (8670) while the lowest dielectric loss (0.38) was recorded by BSNBS 0.10 sample, measured at 1 MHz.
Synthesis and Characterization of PZT Doped Lanthanum, Neodymium and Yttrium Using Sol Gel Method
Authors: Jamil Amerul Azree , Johar Banjuraizah , Khor Shing Fhan , Ahmad Zainal Arifin
Published: January 2016

PZT ceramic is synthesis by using sol gel method.Introducing a dopant to the pure PZT can help to enhance the properties of the piezoelectric ceramic. The effects of sintering temperature on phase formation, densification of the ceramics have been investigated using XRD, SEM and Archimedes method. The bulk density and porosity of PZT decreased as the sintering temperature increased.
Preparation and Characterization of Porous Cordierite for Catalyst Support Application
Authors: Kok Eing Kuan , Johar Banjuraizah , Khor Shing Fhan , Ahmad Zainal Arifin
Published: January 2016

This paper aims at studying the porous cordierite ceramics prepared by using the non-stochiometric cordierite composition formulation (2.8MgO.1.5Al2O3.5SiO2) by PU sponge impregnated method. The ceramic suspension were prepared with non-stoichiometric formulation of cordierite and sintered at 1250 °C, 1275 °C, 1285 °C, 1300 °C and 1325 °C. The phase transformation of non-stochiometric formulation cordierite was investigated by XRD. This paper also aims to compare the effect of linear shrinkage, porosity and density of 20 wt.% PEG treated PU sponge with untreated PU sponge respectively corresponding to different pore content (100 ppi, 80 ppi, 60 ppi, and 40 ppi). The pore structure was analyzed by SEM.
Preparation and Characterization of Hydrophobic Ceramic Foam
Authors: Suparman Nur Syazana , Ahmad Alwi Khadijah , Muhamad Nor Mohd Al Amin
Published: January 2016

Ceramic foam are a class of high porosity materials that are used for various applications. In this study, foam ceramic porcelain powder was produced by using polymeric sponge replication method at different solid content ranging from 30 to 50 wt. %. Properties of ceramic foam was characterized for porosity and density. Ceramic foam then grafted with methyltriethoxysilane (MTMS) at different concentration ranging from 0 to 9.0% v/v to determine hydrophobic effect and oil absorption capacity. From the results, it was found that the density of ceramic foam increased while porosity was decreased with increasing solid contents. It is clearly seen that, MTMS grafting contribute to hydrophobic effect of ceramic foam which enable repelling of water. The amount of oil absorbed by ceramic was found increased by increasing concentration of MTMS for all solid contents. As conclusion, MTMS give significant effects on hyrdophobic ceramic foam and produce good absorption capacity. The lower solid content produced better oil absorption compared to higher solid content due to presence of higher porosity.
Mechanical and Morphological Properties of Meranti Wood Flour Filled Polypropylene Composites
Authors: Abu Bakar Mohamad Bashree , Masri Mohamad Najmi , Mohamad Amini Mohd Hazim , Mohamed Mazlan , Sulaiman Muhammad Azwadi , Nik Yusuf Nik Alnur Auli , Thirmizir Mohd Zharif Ahmad , Mohd Ishak Zainal Arifin
Published: January 2016

Wood plastic composites (WPC) have been produced by compounding meranti wood flour (WF) with polypropylene (PP) copolymer using a twin-screw extruder. The meranti WF content was varied from 30 to 60 wt.%. The mechanical properties, i.e. tensile, flexural and impact of the composites were determined on injection-molded specimens. The tensile fractured surfaces were used to study the morphological properties of the composites. The result shows that the increment in WF content has given a significant improvement in modulus properties but at the expense of strength and toughness properties. A commercial maleic anhydride grafted polypropylene (MAPP) compatibilizer at 5 wt.% was incorporated into the PP40/WF60 formulation. The strength, stiffness and toughness properties were improved significantly in the presence of MAPP. The morphology of the composites was studied by scanning electron microscopy (SEM). The improvement of the fibre-matrix adhesion between the WF and PP matrix as revealed by SEM is believed to be one of the major reasons for the improved mechanical properties.
Posttranscriptional and Translational Control of Gene Regulation in CD4+ T Cell Subsets
Authors: Istomine Roman , Pavey Nils , Piccirillo Ciriaco A.
Published: January 2016

The immune system is under strict regulatory control to ensure homeostasis of inflammatory responses, lying dormant when not needed but quick to act when called upon. Small changes in gene expression can lead to drastic changes in lineage commitment, cellular function, and immunity. Conventional assessment of these changes centered on the analysis of mRNA levels through a variety of methodologies, including microarrays. However, mRNA synthesis does not always correlate directly to protein synthesis and downstream functional activity. Work conducted in recent years has begun to shed light on the various posttranscriptional changes that occur in response to a dynamic external environment that a given cell type encounters. We provide a critical review of key posttranscriptional mechanisms (i.e., microRNA) and translational mechanisms of regulation of gene expression in the immune system, with a particular emphasis on these regulatory processes in various CD4+ T cell subsets.
Phenotypic detection and molecular characterization of beta-lactamase genes among Citrobacter species in a tertiary care hospital
Authors: Praharaj Ashok Kumar , Khajuria Atul , Kumar Mahadevan , Grover Naveen
Published: January 2016

Objective: To examine the distribution, emergence, and spread of genes encoding beta-lactamase resistance in Citrobacter species isolated from hospitalized patients in a tertiary care hospital. Methods: A prospective study was conducted in a 1000-bed tertiary care center in Pune, India from October 2010 to October 2013. A total of 221 Citrobacter spp. isolates were recovered from clinical specimens from different patients (one isolate per patient) admitted to the surgical ward, medical ward and medical and surgical Intensive Care Units. Polymerase chain reaction (PCR) assays and sequencing were used to determine the presence of beta-lactamase encoding genes. Conjugation experiments were performed to determine their transferability. Isolate relatedness were determined by repetitive element based-PCR, enterobacterial repetitive intergenic consensus-PCR and randomly amplified polymorphic DNA. Results: Among 221 tested isolates of Citrobacter spp. recovered from various clinical specimens, 179 (80.9%) isolates showed minimum inhibitory concentration (MIC) >4 μg/ml against meropenem and imipenem. One hundred and forty-five isolates with increased MICs value against carbapenems were further processed for molecular characterization of beta-lactamase genes. Susceptibility profiling of the isolates indicated that 100% retained susceptibility to colistin. Conjugation experiments indicated that blaNDM-1was transferable via a plasmid. Conclusion: The ease of NDM-1 plasmid transmissibility may help their dissemination among the Citrobacter species as well as to others in Enterobacteriaceae. Early detection, antimicrobial stewardship and adequate infection control measures will help in limiting the spread of these organisms.
Analytic hierarchy process as module for productivity evaluation and decision-making of the operation theater
Authors: Ezzat Abdelrahman E. M. , Hamoud Hesham S
Published: January 2016

The analytic hierarchy process (AHP) is a theory of measurement through pairwise comparisons and relies on the judgments of experts to derive priority scales, these scales that measure intangibles in relative terms. The aim of the article was to develop a model for productivity measurement of the operation theater (OT), which could be applied as a model for quality improvement and decision-making. AHP is used in this article to evolve such a model. The steps consist of identifying the critical success factors for measuring the productivity of OT, identifying subfactors that infl auence the critical factors, comparing the pairwise, deriving their relative importance and ratings, and calculating the cumulative effect according to the attributes in OT. The cumulative productivitycan be calculated by the end and can be compared Ideal productivity to measure the productive of OT in percentage fraction. Hence, the productivity could be calculated. Hence, AHP is a very useful model to measure the productivity in OT.
Does interpersonal regulatory fit affect intergenerational communication? Elder advice and younger gratitude
Authors: Tabuchi Megumi , Kamiariya Moeko , Miura Asako
Published: January 2016

Old people have considerable experience and wisdom to share with young people; however, young people do not always listen to old people with gratitude. We conducted two studies to examine the effect of regulatory fit on young people’s gratitude toward old advisers. As predicted, young people felt more grateful to old advisers whose advice did not “fit” the advisees’ self-regulatory orientation, whereas young people felt more grateful to young advisers whose advice fit the advisees’ self-regulatory orientation (lab experiment in Study 1, Web survey in Study 2). Using these results, we propose an idea that may promote smoother intergenerational interaction in transmitting experience and wisdom from older to younger generations.
Socio-Economic Status of the Street Children in Bangladesh
Authors: Hossain Sheikh Abir , Alam Md. Ashraful
Published: January 2016

Basically, the children who are in situations of poverty, illiteracy, disease and social injustice have been focused on this study and have been prioritized those children who sleep on streets, railway terminals and platforms, bus stations, parks and open spaces, religious centers, construction sites and around graveyard and in other public places with no roof in scale. A survey has been conducted on a sample of 101 children from two purposively selected areas of Dhaka city to gather information on their Socio-economic status by using quantitative method. Findings reveal that the street dwellers had to adopt a very precarious and humiliating life on the streets devoid of all basic amenities of life, under constant threat of eviction and harassment by the bad people and hoodlums. They work hard to meet their demands but due to their involvement in low paying informal sector, their demands are hardly filled out. They cannot improve their conditions at all even after five or more years of street-living. According to them, housing, food, and lack of jobs are the three most common problems for which they are to seek assistance and to live in the street for unknown period.
My Daughter the Scientist? Mothers’ Perceptions of the Shift in Their Daughter’s Personal Science Identities
Authors: Farland-Smith Donna
Published: January 2016

This study reports on the perspective of mothers whose daughters underwent an extensive inquiry-focused interactive one-week science camp, which involved female middle school students and university scientists. This study focused on nine mother’s perceptions of the impact the camp had on their daughter’s science identities. Following the camp, parents were interviewed and reported that, among other things, their daughters had shifted to a much keener appreciation for science as a discipline, had a greater awareness of who scientists are, where their work, and what they do, as well as a broadened and more focused interest in science careers. Key to this paper is the profound ripple effect that these experiences with scientists had on the girls’ science identities once returning to a school setting. Based on data collected, these experiences with scientists prompted students to participate more in school science and express more interest in science for as much as a year following the camp. The reflections shared by parents following their daughters’ camp participation provide important insight for parents, teachers and informal educators in terms of how girls internalize these experiences in a way that effects their own perceptions of scientists and becomes incorporated into their individual science identities.
Tirofiban as Treatment for Acute Retinal Artery Occlusion following Internal Carotid Artery Flow Diverter Implantation
Authors: Pierro Luisa , La Spina Carlo , Corvi Federico , Cicinelli Maria V. , Scomazzoni Francesco , Cappelletti Alberto , Bandello Francesco
Published: January 2016

Purpose

To report a favorable outcome of branch retinal artery occlusion (BRAO) treated by means of early administration of tirofiban, a glycoprotein IIb-IIIa platelet receptor inhibitor.

Methods

Case report.

Results

A 65-year-old woman developed dramatic visual impairment in her left eye secondary to BRAO after left internal carotid artery endovascular reconstruction with flow diverter stent implant; visual acuity was hand motion. A dose of intravenous tirofiban was injected 10 minutes after symptoms onset. Fourteen hours after drug infusion, retinal fluorescein angiography revealed a well-perfused macula with a partial reperfusion of the inferior temporal branch of the central retinal artery; visual acuity was 20/20 in both eyes.

Conclusions

This case supports the effectiveness of tirofiban in secondary BRAO in neurosurgery and may open its usage to further research.
The Integration of Intercultural Business Communication Training and Business English Teaching
Authors: Jingzi Deng , Wenzhong Zhu , Dimond Elizabeth Elendor
Published: January 2016

The cultural information transferred by language is an important part of Business English teaching. Therefore, teachers of Business English should not only improve the language level of the students, but also develop the students' cross-cultural understanding. The cultivation of intercultural business communication (IBC) competence could not be realized by one or several courses, it must be emphasized through the entirety of Business English teaching. For example, elements of intercultural training should be reflected in Business English teaching materials, classroom discourse, teaching activities, and teaching methodology. This paper analyzed the afore-mentioned elements of IBC competence. Utilizing literature reviews and questionnaires, it also revealed problems in teaching and cultivating IBC competence in Business English curriculum and examined what obstacle Chinese students experience in intercultural communication. The author of this paper proposed three principles that should be followed while integrating IBC competence and Business English teaching in order to realize the simultaneous increase of course knowledge and IBC competence, and to further students’ professional knowledge, English language ability, and intercultural business fluency.
Editor's Notes
Authors: Dooly Melinda
Published: January 2016

As the year draws to an end, we offer you a variety of articles for the holiday season. This issue’s featured author is Evelyn Arizpe (Glasgow University) and we also have an interview with  Jazone Cenoz from the University of the Basque Country, accompanied by our regular research articles, all very relevant to current topics in the teaching and learning of language and literature.
An interview with Dr. Jasone Cenoz on multilingual education and translanguaging
Authors: Hernández-Castillo Núria
Published: January 2016

Dr. Jasone Cenoz is Professor of Applied Linguistics in the Department of Research Methods at the University of the Basque Country. Her research interests include multilingual education, the acquisition of English as a third language, language learning in school contexts and minority languages.  The interview published in this issue was conducted in the autumn of 2015 as part of the meetings held with regard to the author’s doctoral thesis and research interests during a brief stay in Donostia (Spain).
Ecología y literatura en la poesía chilena contemporánea: "Semi ya", de Cecilia Vicuña, y “Cardosanto”, de Soledad Fariña
Authors: Ariz Castillo Yenny Karen
Published: January 2016

Se analiza, desde una perspectiva ecocrítica, la relación intertextual explícita entre las obras de dos poetas chilenas, Cecilia Vicuña (Santiago de Chile, 1948) y Soledad Fariña (Antofagasta, Chile, 1943), producida a partir de la instalación poético-visual Semi ya (2000) de Vicuña, que Fariña actualiza en el poema “cardosanto”, del volumen Donde comienza el aire (2006). El referido poema se presenta como un homenaje poético al trabajo multidisciplinario de Vicuña en general, que combina la poesía, las artes visuales, el cine, entre otros dominios artísticos, e involucra la preocupación por la ecología y la recuperación de los saberes indígenas.
La poesía de Olga Orozco o la contemporánea conciencia de Job
Authors: Martín López Sarah
Published: January 2016

El presente artículo propone una lectura de la obra poética de una importante autora hispanoamericana contemporánea y, más concretamente, argentina: Olga Orozco. Desde una perspectiva novedosa, que imbrica poesía y conocimiento a través del relato de Job –es decir, desde los quicios de Dios y el Mal radical, y el controvertido dilema de la justicia-, se plantea una lectura de la poética orozquiana considerando su raíz surrealista, su utópica pugna con el lenguaje o el establecimiento de esa conciencia de caída que se halla en la médula de su obra poética. Por medio de distintos poemas donde se realiza un continuo balance y un imposible equilibrio, se muestra cómo la poesía de Orozco está tan atravesada por el afán de la analogía como por el peso de la existencia, el paso del tiempo o la conciencia de muerte.
Oscar Muñoz bajo el relámpago. Temporalidad latinoamericana y arte colombiano contemporáneo
Authors: Gil Sabrina Soledad
Published: January 2016

La recurrente apelación a la historia en producciones artísticas colombianas contemporáneas invita a reflexionar en torno a las concepciones sobre el tiempo que subyacen en ellas, así como sobre las relaciones del sujeto contemporáneo con el pasado histórico y el presente. En este marco, analizamos obras del artista Oscar Muñoz, reunidas en su muestra Protografías, como expresión de tensiones entre temporalidades, donde se pondrían en crisis nociones dominantes de progreso y evolución.
Exploraciones espirituales del Atlántico negro: limbo imagination en la novela Las negras brujas no vuelan de Eliseo Altunaga
Authors: Urioste-Buschmann Martina
Published: January 2016

Este artículo explora el tratamiento de la memoria colectiva de la esclavitud en la novela cubana Las negras brujas no vuelan, publicada en 2007 en La Habana por el autor Eliseo Altunaga. El análisis se centra en pasajes determinados que escenifican el estado de trance espiritual experimentado por la protagonista afrocubana Yoandri, quien vive en La Habana de los años noventa y quien se deja iniciar en el culto religioso afrocubano Palo Monte. Como fuente teórica del análisis se recurre al concepto de la limbo imagination que plantea el escritor guayanés Wilson Harris en su obra ensayística.
Sujeto y comunidad; voz, isla y muerte en la narrativa cubana del siglo XXI
Authors: Timmer Nanne
Published: January 2016

Este artículo explora cómo dos novelas cubanas de 2010 y 2012 tratan el tema del sujeto y de la comunidad. En Desde los blancos manicomios, de Margarita Mateo y en Días de entrenamiento, de Ahmel Echevarría se repiensa la comunidad y se imagina un futuro atravesando los temas de la muerte, el yo, y la isla. La tensión entre sujeto y símbolo nacional es crucial en estas narrativas, y a través de ella se articula la búsqueda de voz, vida y cuerpo en visiones contemporáneas sobre la singularidad.
Perturbaciones subversivas o sobre los márgenes de la “buena vida” en Mundo Cruel de Luis Negrón
Authors: Vera Rojas María Teresa
Published: January 2016

A partir de las consideraciones de Judith Butler sobre el carácter normativo y normalizador contenido en el concepto de la “buena vida” y de lo “humano”, en este artículo se reflexiona sobre los límites de la inteligibilidad cultural de los sujetos que, como los personajes de Mundo cruel (2010), habitan los márgenes de las “vidas vivibles”. Esta aproximación no se orienta, sin embargo, hacia el cuestionamiento de las exclusiones/expulsiones ni se formula desde el lugar dicotómico de la hetero/homonormatividad, lo que se busca es destacar la posibilidad subversiva y no-normativa del margen/frontera ¾sexual, económico, ciudadano, urbano, familiar¾ en el que residen y se posicionan los personajes patos/maricones/locas de Santurce, barrio sanjuanero en el que Luis Negrón enmarca los relatos de Mundo cruel.
Los soles truncos: la obra, el autor, su visión, su representación y su travestismo
Authors: Del Valle Jesús , Rivera Myrna
Published: January 2016

El análisis presentado tiene dos vertientes que están intrínsecamente ligadas. Por un lado, se ofrece la teoría que le subyace a la construcción del sujeto femenino, y su relación con el patriarcado, en la obra Los soles truncos del dramaturgo clásico puertorriqueño René Marqués. Y, por otro, se escenifica en una lectura teatralizada la construcción de sus sujetos femeninos en clave queer/travesti: ejercicio de experimentación que saca a flote su transfiguración discursiva deslizando sus márgenes y sus fronteras. La segunda parte de este artículo se centra, pues, en las problemáticas de una representación alternativa de la pieza.
Yerba prendida (cubanos a la deriva/fronteras que no se besaron)
Authors: Cuesta Mabel
Published: January 2016

Ensayo
La literatura dominicana en el contexto caribeño: ¿cómo seguir pensando los inicios de las vanguardias?
Authors: Mena Miguel D.
Published: January 2016

Ensayo
Structural changes during the overoxidation of electrochemically deposited poly(3,4-ethylenedioxythiophene) films
Authors: Ujvari Maria , Láng Győző G. , Vesztergom Soma , Szekeres Krisztina J , Kovács Noémi , Gubicza Jenő
Published: January 2016

Electrochemical, mechanical and morphological properties of thin poly(3,4-ethylenedioxy-thiophene) (PEDOT) films deposited on gold were investigated in aqueous sulfuric acid and sodium sulphate solutions. At sufficiently positive electrode potentials overoxidation of the polymer took place and resulted in morphological changes and structure evolution. These effects were monitored by electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) and X-ray diffraction. Significant changes in the film stress caused by overoxidation were detected by using the electrochemical bending beam method. Results of the EIS measurements proved that the charge transfer process at the metal/film interface is more hindered in case of the degraded film. According to SEM images the overoxidation/degradation of PEDOT films can result in random-like but quite well-ordered arrays of islands and trench-like structures. The diffraction peaks of PEDOT became sharper and more intensive during the subsequent oxidation cycles indicating an increase in the degree of crystallinity of the polymer.
Autobiografias de designers de moda como ferramentas para pesquisa histórica
Authors:   Università Iuav di Venezia, Vaccari Alessandra , Esteves Jennifer ,   Universidade do Estado de Santa Catarina
Published: January 2016

Os designers de moda constituem uma parte da moda ocidental moderna e estão entre as mais intrigantes e controversas figuras. A moda é um sistema centrado no design, mas que tende a excluir o designer do discurso teórico e histórico. Em outros campos das produções culturais, artistas e arquitetos deram um enfoque crucial - por meio de seus escritos - sobre os principais temas em suas áreas, contribuindo assim para desenvolvê-los na historiografia e na literatura. No caso da moda, ao contrário, o material textual que os designers de moda produzem é considerado promocional para eles próprios, para suas coleções e para sua marca. Esta interpretação é aceita pela indústria da moda, bem como pelos estudos de moda, que reconhecem a contribuição extremamente limitada dos designers à historiografia e à crítica. Este trabalho pretende discutir o papel histórico e contemporâneo das explanações dos designers no campo da moda. Levando-se em consideração as publicações de estilistas de moda do século XX e XXI, o trabalho explora relatos autobiográficos de designers de moda sobre sua entrada no mundo da moda, com especial atenção a sua educação e aos períodos como aprendizes[1]. Também se apresenta uma visão sobre as dificuldades que os designers encontram na gestão de sua imagem pública.
A branquidade conservadora de Vogue Brasil no século XXI
Authors:   Université Sorbonne, Novelli Daniela
Published: January 2016

A presente reflexão é parte integrante de recente pesquisa doutoral interdisciplinar sobre a produção imagética, narrativa e discursiva de uma branquidade conservadora nas páginas do periódico de alta moda e prêt-à-porter de luxo Vogue Brasil. Questões teórico-metodológicas inseridas notavelmente nos campos dos estudos culturais, de gênero e pós-coloniais são articuladas por meio de uma análise qualitativa de dois editoriais de moda, publicados nos anos de 2007 e 2008 e apontam para o “autoexotismo” da natureza e de nossa cultura popular – marcado simbolicamente pela primazia do corpo [branco] feminino, considerando-se ainda a legitimação de vozes produtoras de discursos de competência e renovação constante, bem como o cruzamento da violência simbólica racial com outras formas de dominação (de classe e de gênero/sexual).
Um olhar sobre o papel da mulher rendeira na história da moda brasileira
Authors:   Universidade Federal do Rio Grande do Sul, Silva Vera Lucia Felippe da , Rüthschilling Evelise Anicet , Figueiredo Joana Bosak de
Published: January 2016

O presente artigo faz uma reflexão sobre o papel da mulher rendeira na sociedade brasileira, discutindo as transformações, a apropriação do conhecimento e as ressignificações do fazer manual de rendas no século XX e XXI. Para isso, apoia-se na análise de imbricamentos sociais e culturais com abordagem pela micro-história de vida da senhora da alta sociedade carioca, rendeira, usuária e colecionadora. Analisando os dois principais cenários sociais, a elite e a classe trabalhadora, verificou-se que a relação de produção de rendas, nos séculos estudados, modificaram-se em decorrência do atual modelo de vida das mulheres.