bluuebunny/crossref_metadata_2025 huggingface dataset:
Forming Mechanism of α-Fe2O3 in the Oxide Films on Iron-Bonded Diamond Wheel Surface by ELID Grinding
Authors: Zhang Hua Li , Kuai Ji Cai
Published: December 2016

The formation mechanism of α-Fe2O3 on iron-bonded diamond wheel surface by ELID grinding is presented here. X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) techniques were used to analyze the compositions of the oxide films. X-ray diffraction analysis demonstrated the existence of the diffraction peak of α-Fe2O3, which was observed in ELID grinding iron-bonded diamond wheel surface. To illustrate the correctness of our theory, X-ray photoelectron spectroscopy analysis was also performed. Results reveal that the characteristic spectrum of oxide film on ELID wheel has coincidence with the standard spectrum of Fe2p in α-Fe2O3. These results suggest the existence of α-Fe2O3 in oxide films on the grinding wheel surface. The potentiality that α-Fe2O3 can bring polishing effect to ELID grinding process has also been discussed. It helps understand how ELID grinding can achieve excellent surface finish for the workpiece.
Structural Modification of Polymer Nanocomposites Based on Tetrazole
Authors: Lushin Evgeniy N. , Castro Rene Alejandro
Published: December 2016

Structural features and dielectric behavior of polymeric systems based on tetrazole are investigated after combining them with potassium nitrate (KNO3) and potassium chloride (KCl). It was found that the salt additives added to the system exist in the form of the singular crystallites that is the closed inclusions chaotically distributed inside polymeric matrix. Injection of potassium nitrate increases the value of dielectric permittivity on the studied interval of frequencies. Potassium chloride reduces the value of dielectric permittivity of the polymeric system in the field of high frequencies, and increases it in the field of low frequencies. Addition of salt increases the specific conductivity of composites that indicates increase in degree of dissociation of ionogenic substances. In the studied systems, ionogenic substances, besides salt additives, including water and remains of catalysts.
TEM and XRD Analysis of Carbon Nanotubes Synthesised from Flame
Authors: Tan Win Hon , Lee Siew Ling , Chong Cheng Tung
Published: December 2016

A premixed flame burner system was utilised to synthesise carbon nanotubes (CNTs). The morphologies of highly-graphitic carbon nanotubes were characterised by using transmission electron microscopy (TEM) and X-ray powder diffraction (XRD). The XRD analysis shows the spectrum of a typical CNT, while TEM imaging shows the physical structure of the carbon nanotubes. CNTs were grown effectively on a Ni-contained substrate in an elevated temperature environment. The flame synthesised CNTs were of high crystalline, multi-wall structure, and contained relatively less impurities and amorphous carbon. The CNT intershell spacing values quantified using TEM and XRD are 0.317 nm and 0.344 nm respectively. CNTs produced from flame synthesis are based on the tip-growth model and vapor-liquid-solid (VLS) mechanism.
Hardware-Technological Features of Layered Surface Composition Made of Shape Memory Materials in a Single Vacuum Cycle
Authors: Rusinov Peter Olegovich , Blednova Zhesfina Michailovna
Published: December 2016

In this article we explained why it is reasonable to create a layered surface composition using multicomponent materials with shape memory effect (SME) to improve reliability, durability and extend the life cycle of mechanical engineering products. We developed and patented hardware and technological solutions in order to test the composition formation technology. These solutions help us to form the layers made of shape memory materials, which have gradient distribution of properties and capabilities in a single vacuum cycle. We demonstrated ample opportunities of complex surface composition method with shape memory materials, including mechanical activation, high-velocity oxygen-fuel spraying (HVOF), thermal and thermomechanical processing. This allows us to create nanostate and maintain functional and mechanical properties of shape memory materials. As an example, we demonstrated the results of statistical simulation of HVOF technology by shape memory material Ti51Ni44Cu5, that was made by means of algorithmic planning and allowed us to optimize treatment modes according to the following criteria: adhesive strength, porosity and nanostructured state.
Production of Syngas from Controlled Microwave-Assisted Pyrolysis of Crude Glycerol
Authors: Leong Swee Kim , Ani Farid Nasir , Chong Cheng Tung
Published: December 2016

Conversion of crude glycerol into synthesis gas was studied by using controlled microwave-assisted pyrolysis method. Pyrolysis of crude glycerol in the presence of carbonaceous catalyst was performed in a fixed bed reactor under oxygen-deficient environment using a domestic microwave. The effects of inert carrier gas flow rate and pyrolysis temperature on the product yield were investigated. Characterisation of the gaseous product showed that hydrogen, methane and carbon dioxide are the main components in the gaseous product. High temperature and low inert carrier gas flow rate are effective in pyrolysing crude glycerol due to sufficient energy and residence time for complete cracking of vapour into small gaseous molecules. Peak hydrogen yield of 35.2% by volume was obtained at the carrier gas flow rate of 100 mL/min and 600 °C.
Application of Calcium Methoxide as Solid Base Catalyst for Biodiesel Production from Waste Cooking Oil
Authors: Chumuang Nichaonn , Punsuvon Vittaya
Published: December 2016

In this study, the biodiesel production of waste cooking oil using calcium methoxide as solid base catalyst was investigated. The calcium methoxide catalyst was synthesized from calcined quick lime reacted with methanol. The XRD result showed that the catalyst was successfully synthesized with sufficient purity. The strength of catalyst was examined on the transesterification reaction of waste cooking oil and methanol. Parameters affecting on transesterification such as the catalyst concentration, methanol-to-oil-molar ratio, reaction time and reaction temperature were investigated. The results showed that the percentage of fatty acid methyl ester conversion of 99.06%. The optimum conditions were achieved within 3 h using 3wt% catalyst concentration, 12:1 methanol-to-oil molar ratio and 65°C reaction temperature. In addition, the kinetic study of transesterification reaction was carried out at the temperature from 30°C to 65°C. The pseudo-first order was good agreement with the experiment results. The reaction rate constant (k) and activated energy (Ea) were determined as 0.023 min-1 and 55.77 kJ/mol, respectively.
Study on the Removal of Hydrogen Sulfide from Biogas Biomaterial Using Water Scrubbing
Authors: Lien Cheng Chang , Wang Min Wei , Lin Wei Cheng
Published: December 2016

Biogas typically refers to a mixture of primarily flammable gases produced from organic matters by means of anaerobic fermentation. Since the abundance and renewability of biomasses, biogas deserves the potential of being as an alternative to fossil energy. However, biogas may contain hydrogen sulfide which will damage the facilities, hazardous to the environment and to living beings. The objective of this study is to develop a water scrubbing system to remove hydrogen sulfide from biogas. The efficiency of hydrogen sulfide scrubbing is assured by injecting biogas into circulating water through a diffuser. The diffuser makes the passing biogas into numerous bubbles. The study carried out on combinations of various water circulation flow rates and biogas volumetric flow rates. Experimental results showed that the performance of hydrogen sulfide removal decreases as a result of increasing scrubbing time. The removal efficiency could be maintained at 47.7% with adequate additional fresh water of 10 ℓ /min. The system requires only simple operation and is cost effective and hence it is suitable for small-scale pig farms in waste processing.
Hydrogenous Fuel as an Energy Material for Efficient Operation of Tandem System Based on Fuel Cells
Authors: Zubkova Marina , Stroganov Alexander , Chusov Alexander , Molodtsov Dmitry
Published: December 2016

This paper presents the results of relatively cheap hydrogenous fuel usage as an energy material for energy supply stand-alone environmentally friendly systems creation. Usage of fuel cells running on hydrogenous fuel is a promising direction in creation of stand-alone power supply systems in low-rise residential development. Presented thermodynamic calculations and material balance data for electric and thermal components assessment in considered ways to use convention products, performance enhancement in tandem system based on fuel cells with full heat regeneration. The total effective efficiency of the tandem installation including the fuel converter, separating system, high-temperature fuel cell, low-temperature fuel cell is higher than for each of the fuel cell elements separately. Distribution of H2 for LTFC and HTFC is determined in compliance with the conditions of the positive heat balance to compensate the heat used for the endoenergic reaction in the converter, input stream heating and heat losses. The total effective efficiency under making full use of recovered heat for considered tandem system depends on the efficiency of its constituent fuel cells. Energetically effective distribution of H2 on streams of high-temperature and low-temperature oxidation according to a position of observance of positive thermal balance on an external contour of tandem system, is reached by operation of HTFC electric efficiency in the range of 50 ÷ 55%.
Simulation on Temperature Field of Friction Stir Welding of 2A14 Aluminum Alloy Based on Equivalent Film Method
Authors: Zhu Zhi , Wang Min , Zhang Hui Jie , Zhang Xiao , Yu Tao , Yang Guang Xin
Published: December 2016

Backing plate has an important influence on the temperature field of workpiece during the friction stir welding process. In order to predict the temperature field of workpiece accurately, a thermal-fluid coupled friction stir welding calculation model including workpiece and backing plate was developed. In the model, an equivalent film method was proposed to simplify the contact heat transfer between workpiece and backing plate to a heat conduction problem. The computational fluid dynamic software FLUENT was ultilized to simulate the friction stir welding process of 2A14 aluminum alloy. As a result, the steady-state temperature field during the friction stir welding process was predicted and analyzed. The welding process test was carried out to verify the simulation results of temperature field. The compared results show that the simulated temperature and the measured values of all measuring points are in good agreement. Using the simulation method proposed in this paper, the calculation accuracy of temperature field during the friction stir welding process could be relatively high and the maximum error is 4.61%. In addition, there is a good corresponding relationship between the temperature distribution and the various regions of weld cross section.
Impact of Secondary Phases Content on the Mechanical Properties of Cordierite
Authors: Kok Eing Kuan , Banjuraizah Johar , Ho Li Ngee , Yahidah Zabar
Published: December 2016

The Cordierite ceramic body had been synthesized through conventional techniques solid state reaction by using non-stoichiometric composition (2.5 MgO. 1.8 Al2O3. 5 SiO2). The sintering temperature study was carried out by heat treated the samples at several degree of sintering temperature (1250 °C, 1275 °C, 1300 oC, 1325 °C, 1350 °C and 1375 °C). The qualitative and quantitative of crystalline phase analysis was accomplished by using X-ray Diffraction (XRD) technique and Rietveld structural refinement. The Scanning electron microscopy (SEM) was employed for morphology analysis. The mechanical properties of samples were determined by Vicker’s Hardness test. Rietveld quantitative phase analysis results show that α phase Cordierite constitutes up to 96.4 wt% when the samples was sintered for 2 hours at sintering temperature of 1375 °C and obtained densified and orderly crystal structure arrangement in SEM micrograph except the mechanical strength. The sample obtained the uppermost α phase Cordierite content gained the lowest hardness values (4.00.8GPa). Conversely, the sample contains 90 wt% α-cordierite and 1.4 wt% magnesium titatnate achieve highest hardness which is about 4.90.79GPa.
Extraction Characteristics of the Alkali and Alkaline Earth Metal Ions in the Washing Solution of Coal with Polymer Material Crown Ether
Authors: Chen Hong Wei , Zhang Zhi Yuan , Yu Hai Long
Published: December 2016

The washing solution of Zhundong coal is a multi-ions mixed system, and the extraction reactions of the alkali and alkaline earth metal ions in the water washing solution with polymer material of dicyclohexyl-18-crown-6 were investigated. The results show that the content of Na in the washing solution is highest, followed by K. Dicyclohexyl-18-crown-6 has better extraction rate of K due to the diameter of K has the same size with the hole diameter of dicyclohexyl-18-crown-6, which enables it could effectively separate Na and K, while did not cause excessive pollution of aqueous solution. Alkali and alkaline earth metal ions were extracted by dicyclohexyl-18-crown-6 in the form of 1:1. Improving the concentration of dicyclohexyl-18- crown-6 in organic phase could effectively enhance the extraction rate. It is not conducive to the extraction reaction by increasing temperature, as the extraction reaction is exothermic.
Microscopic Structure and Adsorption Properties of the Terpenoids-Based Adsorption Material
Authors: Zhang Ling , Zhan Zhao Lin , Li Chun Lin , Zhang Tian Dong , Gao Rui , Yang Jian Yun , Yu Xiao Hua
Published: December 2016

In this paper, a new type of natural adsorption materials were prepared by spray granulation. The structure and properties of the product were characterized by scanning electron microscope analysis, N2 adsorption desorption analysis, infrared analysis, X ray diffraction analysis, the rmogravimetric analysis. The results showed that: the best preparation conditions of the adsorption materials were as follows: the temperature was 59.21°C, the pressure was 0.28 Bar, and the rate was 14.15 ml/min. In addition, the natural materials had high porosity and specific surface areas , which was better for adsorption. The pore size was mainly concentrated between 13 ~ 28nm. Moreover, these materials had more functional groups. The decomposition temperature was 250°C,which resulted in better thermal stability. Consequently, the materials had better adsorption properties, and the materials will have better application prospect.
Effect of Niobium Doping on the Properties of Yttria-Stabilised Zirconia for Solid Electrolyte in Solid Oxide Fuel Cell
Authors: Banjuraizah Johar , Lexus Cheong Sze
Published: December 2016

8 mol % Yttria Stabillize Zirconia (8YSZ) generally used as solid electrolyte in solid oxide fuel cell (SOFC). In this study, niobium (0, 1, 2, 3 mol%) doped 8YSZ ceramics were prepared by the conventional solid state process. The mixtures of powders were calcined, compacted into cylinderical pellets, and sintered at 1500°C for 2 hours in air atmosphere. All samples were evaluated for phase stability, microstructure and electrical conductivity. Tetragonal phase was detected as the major phase for all studied samples. With increasing in Nb addition, tetragonal and cubic phase started to transform to monoclinic phase. The introduction of Nb2O5 (more than 0.5 mol %) was not only useful to enhance the densification, but also helpful to enhanced the ionic conductivity of 8YSZ samples. SEM micrographs of niobium-doped zirconia powders indicated the coalesce of fine particles with sizes varying from 10 μm to 1 μm, in response to increasing in Nb content.
Toughening Mechanism and Mechanical Properties Simulation of Rubber-Toughened Polymers
Authors: Song Hong Tu
Published: December 2016

When blending rubbers into polymers, different rubber distribution status and fraction due to different mechanical property. In this research, effective mechanical properties of rubber-toughened polymers with four blending fraction in six kinds of particle distribution status are simulated numerically by using finite element method. Rubber particle distribution model include four 2D models and two 3D models. Typical effective mechanical properties such as yield stress, Young's modulus, Poisson's ratio and stress-strain curve of each status are obtained. The Results show that all models Young's modulus and Poisson's ratio decrease with rubber particle volume fraction increasing. Young's modulus and Poisson's ratio of three-dimensional body-centered cubic and face-centered cubic models are in a close magnitude range, it means rubber particle volume fraction has less effect on 2D models and two 3D models. As we all known, Matrix yielding, crazing and interface debond. All play an important role in the toughening process of rubber-toughened polymers. So in this paper we also study on toughening mechanism using same models. Our simulation takes use of stress concentration factor, yield ratio and interface elements' strain difference which is related with matrix yielding, crazing and interface debond to study the toughening mechanism. Simulation shows that the maximum stress concentration factor increases with particle volume fraction. The shear yielding occurs first at the equator of rubber particle, and then yield region expands from the equator to the pole of the particle with loads increasing.
Study on the Bearing Capacity and Influence Factors of Concrete Columns with Reinforcing Steel Bars in Core
Authors: Fu Ri Rong , Liu Kang Ning , Men Guang Chuang , Hui Li
Published: December 2016

The concrete column with reinforcing bars in core refers that allocate longitudinal reinforcement and stirrup in the core area of the cross section of the concrete column. In this paper, a normal concrete column and a core reinforcement column are analyzed. In the same conditions (the same material, the same section and slenderness ratio) the cross section is analyzed by Xtract cross section analysis software. Through comparison and analysis of the yield surface curve and curve of moment-curvature, it can be drawn that: compared to normal concrete column, the core reinforcement column can significantly improve the bearing capacity and deformation capacity of the whole column; if the volume stirrup rate and the longitudinal reinforcement ratio of the core area increase, the range of the yield surface curve of the column will grow, the bearing capacity of the component will increase. As for seismic design of short columns under high axial pressure, it has a good engineering significance for improving the load-carrying and deformation ability of the short column and meeting the requirements of seismic design.
A Study on Bacteria Adsorption Technology for Development of Bacteria Based Concrete Coating Materials
Authors: Choi Rebecca , Park Ho Young , Choi Byong Jeong , Kim Yeon Bin
Published: December 2016

This Study focused on developing the foundational technologies for coating concrete structures with bacteria. In order to utilize the self-purifying capability of bacteria and improve the durability of the concrete, this Study selects the bacteria to form slime films with and proposers the technology to adsorb such coating. Based on the assessment of the slime formation and growth rate of rhodobater capsulatus on different media, maltose was found to be the optimum medium condition. Then, different adsorption materials were used to fix the rhodobater capsulatus cultivated on the proposed medium, and their adsorption characteristics were assessed through image analysis. The high-porous resin is recommended for rhodobater capsulatus adsorption.
LQG Control of Along-Wind Responses of Tall Building Using Composite Tuned Mass Dampers
Authors: Kim Young Moon , You Ki Pyo , You Jang Youl , Paek Sun Young , Nam Byung Hee
Published: December 2016

A composite tuned mass damper(CTMD) is a vibration control device consisting of an active-passive tuned mass dampers supported on the primary vibrating structure. The performance of CTMD in mitigating wind-induced vibration of tall building is investigated. Optimum parameters of a passive tuned mass damper(PTMD)for minimizing the variance response of the damped primary structure under random loads, with different mass ratio of an active tuned mass damper(ATMD) to a PTMD have been used for the optimum parameters of CTMD. The active control force generated by ATMD actuator was estimated by using linear quadratic Gaussian(LQG) controller, and the fluctuating along-wind load, treated as a stationary random process ,was simulated numerically using the along-wind load spectrum proposed by Solari .Comparing the along-wind rms response of tall building without a CTMD, the CTMD is effective in reducing the response to 40%~45% of the response without the CTMD. Therefore, the CTMD system was effective in reducing wind-induced vibration of tall building.
Numerical Analysis of Blast Load from Explosive Materials Using Finite Volume Method
Authors: Lidner Michał , Szcześniak Zbigniew
Published: December 2016

A method of numerical analysis of the phenomenon of the air shock wave propagation is presented. The paper describes an explicit own solution. It uses Finite Volume Method (FVM). It also takes into account energy losses due to a heat transfer. For validation, the results of numerical analysis were compared with the literature reports. Both one-dimensional (an explosion in the pipe) and three-dimensional (explosion within the compartment) flow of a shock wave were analysed. Values of impulse, pressure, and its duration were studied. Finally, an overall good convergence of numerical results with experiments was achieved. Also the most important parameters were well reflected.
Bearing Capacity Improvement of Shallow Foundations Using Cement-Stabilized Sand
Authors: Rasouli Habib , Takhtfirouzeh Hana , Taghavi Ghalesari Abbasali , Hemati Roya
Published: December 2016

In order to attain a satisfactory level of safety and stability in the construction of structures on weak soil, one of the best solutions can be soil improvement. The addition of a certain percentage of some materials to the soil may compensate for its deficiency. Cement is a suitable material to be used for stabilization and modification of a wide variety of soils. By using this material, the engineering properties of soil can be improved. In this study, the effect of soil stabilization with cement on the bearing capacity of a shallow foundation was studied by employing finite element method. The material properties were obtained by conducting experimental tests on cement-stabilized sand. Cement varying from 2% to 8% by soil dry weight was added for stabilization. The effect of reinforced soil block dimensions, foundation width and cement content were investigated. From the results, it can be figured out that by stabilizing the soil below the foundation to certain dimensions with the necessary cement content, the bearing capacity of the foundation will increase to an acceptable level.
Compressive Strength and High-Temperature Residual Strength of Cement Specimens Containing Bagasse Ash
Authors: Wang I Feng , Lee Cheng Haw , Lu Chun Ku
Published: December 2016

Cement is currently the most versatile and widely used material in construction. However, the high carbon emissions and energy consumption associated with the manufacture of cement remains a serious concern. bagasse ash (BA) is a secondary waste product of bagasse-fired power generation. This study investigated the use of BA as a replacement for cement as a means of reducing the environmental impact of concrete-based construction. At 28 days, we measured the water absorption of cement mortar specimens as well as the compressive strength at room-temperature and after heating. Experiments were conducted involving the replacement of various proportions of cement using BA and fly ash (FA), followed by a comparison of the physical properties. Our test results demonstrate the applicability of BA in the production of cement mortar mixtures with high water-binder ratios. It was found that the water-binder ratio determines the optimal proportion of BA when used as a replacement for cement, wherein a higher water-binder ratio means that more of the cement can be replaced with BA. In compressive strength respect, the optimal cement replacement with BA was 15 % to 25 %, whereas the optimal cement replacement with FA was 20 %. BA was shown to have a more pronounced effect in reducing water absorption in cement mortar specimens with high water-binder ratios (0.55 to 0.65). The compactness of specimens with lower water absorption enables them to retain more of their initial compressive strength following exposure to high temperatures.
Application of Environmentally Friendly Materials in Landscape Infrastructure
Authors: Yi Qiu Li , Xu Ke , Zhai Jun
Published: December 2016

Nowadays, as the consumption of traditional materials has caused serious urban environmental problems, more and more people are seeking ways to solve it. Using alternative materials such as environmentally friendly materials is a way to tackle the problem from the source itself. Combining with the study of landscape infrastructure, which is a new way to dig into problems of a city, they can be much more practically significant. This paper summarizes the features and properties of environmentally friendly materials, then analyzes cases of applying environmentally friendly materials through the research and formation of landscape infrastructure. Through the usage of environmentally friendly materials, these projects ease the contradiction between traditional materials and environment and between development and ecology. Finally, realize the sustainable development of cities and the coordination between man and nature.
Organo-Mineral Additive Based on Mixed Clays
Authors: Loganina Valentina Ivanovna , Skachkov Jury , Demyanova Valentina , Uchaeva Tatyana
Published: December 2016

The possibility of receiving the organo-mineral additive based on polymineral high-montmorillonite clays is considered. It is offered to use nonionic surface-active agents as an organic component. The organo-mineral additive is offered to be used in paints and dry building mortars (DBM) compositionas the structuring, thixotropic and dispersing additive. The DBM composition has been developed, including lime, glass sand, modifying additives and organo-mineral additive. It is shown, that including organo-mineral additive allows to increase coating offset resistance.
Identification of a novel collagen type IV alpha-4 (COL4A4) mutation in a Chinese family with autosomal dominant Alport syndrome using exome sequencing
Authors: Deng Sheng , Xu Hongbo , Yuan Jinzhong , Xiao Jingjing , Yuan Lamei , Deng Xiong , Guan Liping , Zhu Anding , Rong Pengfei , Zhang Jianguo , Deng Hao
Published: December 2016

Background & objectives:

Alport syndrome (AS) is an inherited disorder characterized by glomerulonephritis and end-stage renal disease (ESRD). The aim of this study was to identify the gene responsible for the glomerulopathy in a Chinese family with autosomal dominant AS using exome sequencing.

Methods:

A 4-generation, 30-member Chinese Han family was enrolled in this study. Exome sequencing was conducted in the proband of the family, and then direct sequencing was performed in family members of the pedigree and 100 normal controls.

Results:

A novel frameshift mutation, c.3213delA (p.Gly1072Glufs*69), in the collagen type IV alpha-4 gene (COL4A4) was found to be the genetic cause. Neither sensorineural hearing loss nor ocular abnormalities were present in the patients of this family. Other clinical features, such as age of onset, age of ESRD occurring and disease severity, varied among the patients of this family.

Interpretation & conclusions:

A novel frameshift mutation, c.3213delA (p.Gly1072Glufs*69) in the COL4A4 gene, was identified in the Chinese pedigree with autosomal dominant AS. Our findings may provide new insights into the cause and diagnosis of AS and also have implications for genetic counselling.
Subtelomeric rearrangements in Indian children with idiopathic intellectual disability/developmental delay
Authors: Mohan Shruthi , Koshy Teena , Vekatachalam Perumal , Nampoothiri Sheela , Yesodharan Dhanya , Gowrishankar Kalpana , Kumar Jeevan , Ravichandran Latha , Joseph Santhosh , Chandrasekaran Anupama , Paul Solomon F. D.
Published: December 2016

Background & objectives:

Subtelomeres are prone to deleterious rearrangements owing to their proximity to unique sequences on the one end and telomeric repetitive sequences, which increase their tendency to recombine, on the other end. These subtelomeric rearrangements resulting in segmental aneusomy are reported to contribute to the aetiology of idiopathic intellectual disability/developmental delay (ID/DD). We undertook this study to estimate the frequency of subtelomeric rearrangements in children with ID/DD.

Methods:

One hundred and twenty seven children with idiopathic ID/DD were tested for subtelomeric rearrangements using karyotyping and FISH. Blood samples were cultured, harvested, fixed and GTG-banded using the standard protocols.

Results:

Rearrangements involving the subtelomeres were observed in 7.8 per cent of the tested samples. Detection of rearrangements visible at the resolution of the karyotype constituted 2.3 per cent, while those rearrangements detected only with FISH constituted 5.5 per cent. Five deletions and five unbalanced translocations were detected. Analysis of parental samples wherever possible was informative regarding the inheritance of the rearrangement.

Interpretation & conclusions:

The frequency of subtelomeric rearrangements observed in this study was within the reported range of 0-35 per cent. All abnormal genotypes were clinically correlated. Further analysis with array technologies presents a future prospect. Our results suggest the need to test individuals with ID/DD for subtelomeric rearrangements using sensitive methods such as FISH.
Effect of a polyherbal formulation cream on diabetic neuropathic pain among patients with type 2 diabetes – A pilot study
Authors: Viswanathan Vijay , Rajsekar Seena , Selvaraj Bamila , Kumpatla Satyavani
Published: December 2016

Background & objectives:

Painful diabetic neuropathy is a common complication of diabetes and can severely limit patients’ daily functions. The aim of this pilot study was to evaluate the safety and effect of using a polyherbal formulation in reducing the symptoms of diabetic neuropathic pain in comparison with placebo among patients with type 2 diabetes.

Methods:

A total of 50 (M:F = 33:17) consecutive type 2 diabetes patients with painful diabetic neuropathy were enrolled in this study. All these patients had either two or more symptoms of diabetic neuropathy such as pain, burning and pricking sensations and numbness in their feet. They were randomly assigned to two groups: group 1 (n = 26) patients were treated with polyherbal formulation cream and group 2 (n = 24) patients were administered placebo. The patients were followed up for six months. Changes in the symptoms of painful diabetic neuropathy of each patient were recorded at baseline, third and sixth month using the Diabetic Neuropathic Score.

Results:

The mean age of the patients, duration of diabetes and glycated haemoglobin (HbA1c) were similar in both groups at baseline. During follow up visits, there was a decrease in the HbA1c levels in the study and control groups. The symptoms of painful diabetic neuropathy were also similar in both groups at baseline. A significant decrease in symptoms of neuropathic pain was observed among the group of patients treated with polyherbal formulation cream (76.9 per cent) compared to the placebo-treated group (12.5 per cent) (P<0.001), at the end of the final follow up.

Interpretation & conclusions:

In this pilot study polyherbal formulation cream was found to be effective as well as safe to treat painful diabetic neuropathy. However, its long term use needs to be evaluated for any further effectiveness and side effects.
Circulating heat shock protein mRNA profile in gestational hypertension, pre-eclampsia & foetal growth restriction
Authors: Hromadnikova Ilona , Dvorakova Lenka , Kotlabova Katerina , Kestlerova Andrea , Hympanova Lucie , Novotna Veronika , Doucha Jindrich , Krofta Ladislav
Published: December 2016

Background & objectives:

Heat shock proteins (Hsp) are ubiquitously distributed phylogenetically conserved molecules that regulate cellular homeostasis and maintain the integrity and function of cellular proteins. Increased levels of Hsp in maternal circulation have been shown to be associated with increased risk of pregnancy related complications. The objective of this study was to explore extracellular Hsp mRNA levels in maternal circulation and quantified Hsp27, Hsp60, Hsp70, Hsp90 and Hsp70 binding protein 1 (HspBP1) mRNAs in maternal plasma samples using real-time reverse-transcriptase polymerase chain reaction.

Methods:

Pregnancies with gestational hypertension (GH) (n = 33), pre-eclampsia (PE) with or without foetal growth restriction (FGR) (n = 78) and FGR (n = 25) were involved in the study. Hsp gene expression was analysed in relation to the severity of the disease with respect to the degree of clinical signs, requirements for the delivery and Doppler ultrasound parameters.

Results:

Upregulation of Hsp70 was observed in patients with mild and severe PE (P = 0.004 and P = 0.005, respectively) and in pregnancies complicated with PE delivering before and after 34 wk of gestation regardless of the degree of clinical signs (P = 0.015 and P = 0.009, respectively). No difference in the expression of other Hsp genes among the studied groups was observed. No association between Hsp gene expression and Doppler ultrasonography parameters was found.

Interpretation & conclusions:

These data support that maternal circulation can reflect both maternal and foetal pathologic conditions. Hsp70 represents the sole plasmatic marker, and increased Hsp70 mRNA levels reflect maternal and placental stress response to pregnancy-related complications such as GH and PE, irrespective of the severity of the disease.
Use of hydrogen peroxide vapour & plasma irradiation in combination for quick decontamination of closed chambers
Authors: Mourya Devendra T. , Shahani Hamish C. , Yadav Pragya D. , Barde Pradip V.
Published: December 2016

Background & objectives:

Various conventional methods such as gaseous, vapour and misting systems, fogging, manual spray and wipe techniques employing a number of chemical agents are used for decontamination of enclosed spaces. Among all these methods, use of aerosolized formaldehyde is the most preferred method due to cost-effectiveness and practical aspects. However, being extremely corrosive in nature generating very irritating fumes and difficulty in maintaining a high level of gas concentration, many laboratories prefer the vaporization of hydrogen peroxide (H2O2) as an alternative. We present here the results of using H2O2 vapour in combination with plasma irradiation for quick decontamination of closed chambers.

Methods:

The present study describes a decontamination method, using plasma irradiation in combination with H2O2 (5%). Effect of plasma irradiation and H2O2 on the viability of bacterial spores (Bacillus subtilis), Chikungunya and Kyasanur Forest Disease viruses was assessed.

Results:

Data suggest that with the combination of H2O2 vapour and plasma irradiation, within short time (three minutes), decontamination of surfaces and space volume could be achieved. Although it showed damage of spores present on the strips, it did not show any penetration power.

Interpretation & conclusions:

The results were encouraging, and this method was found to be efficient for achieving surface sterilization in a short time. This application may be useful in laboratories and industries particularly, those working on clean facility concept following good laboratory and manufacturing practices.
Molecular appraisal of intestinal parasitic infection in transplant recipients
Authors: Yadav Pooja , Khalil Shehla , Mirdha Bijay Ranjan
Published: December 2016

Background & objectives:

Diarrhoea is the main clinical manifestation caused by intestinal parasitic infections in patients, with special reference to transplant recipients who require careful consideration to reduce morbidity and mortality. Further, molecular characterization of some important parasites is necessary to delineate the different modes of transmission to consider appropriate management strategies. We undertook this study to investigate the intestinal parasitic infections in transplant recipients with or without diarrhoea, and the genotypes of the isolated parasites were also determined.

Methods:

Stool samples from 38 transplant recipients comprising 29 post-renal, two liver and seven bone marrow transplant (BMT) recipients presenting with diarrhoea and 50 transplant recipients (42 post-renal transplant, eight BMT) without diarrhoea were examined for the presence of intestinal parasites by light microscopy using wet mount, modified Ziehl–Neelsen staining for intestinal coccidia and modified trichrome staining for microsporidia. Genotypes of Cryptosporidium species were determined by multilocus genotyping using small subunit ribosomal (SSUrRNA), Cryptosporidium oocyst wall protein (COWP) and dihydrofolate reductase (DHFR) as the target genes. Assemblage study for Giardia lamblia was performed using triose phosphate isomerase (TPI) as the target gene. Samples were also screened for bacterial, fungal and viral pathogens.

Results:

The parasites that were detected included Cryptosporidium species (21%, 8/38), Cystoisospora (Isospora) belli (8%, 3), Cyclospora cayetanensis (5%, 2), G. lamblia (11%, 4), Hymenolepis nana (11%, 4), Strongyloides stercoralis (3%, 1) and Blastocystis hominis (3%, 1). Multilocus genotyping of Cryptosporidium species at SSUrRNA, COWP and DHFR loci could detect four isolates of C. hominis; two of C. parvum, one of mixed genotype and one could not be genotyped. All the C. hominis isolates were detected in adult post-renal transplant (PRT) recipients, whereas the C. parvum isolates included a child with BMT and an adult with PRT. Clostridium difficle, cytomegalovirus and Candida albicans were found in 2, 3 and 2 patients, respectively.

Interpretation & conclusions:

In the present study, C. hominis was observed as an important parasite causing intestinal infections in transplant recipients. Multilocus genotyping of Cryptosporidium species could detect four isolates of C. hominis; two of C. parvum, one of mixed genotype and one could not be genotyped. Genotyping of G. lamblia revealed that assemblage B was most common.
Transmission of mutans streptococci in mother-child pairs
Authors: Damle S. G. , Yadav Renu , Garg Shalini , Dhindsa Abhishek , Beniwal Vikas , Loomba Ashish , Chatterjee Shailja
Published: December 2016

Background & objectives:

Dental caries is an infectious, transmissible disease. Maternal transfer of mutans streptococci (MS) has been a subject of research. The aim of this study was to evaluate the transmission of MS from mother to children through genetic analysis.

Methods:

Thirty mother–child pairs were included and divided into three groups according to the age of the children. Saliva samples were collected and MS colonies from each mother-child pair were isolated. After inoculation and incubation, MS colonies were submitted to amplification technique by polymerase chain reaction (PCR) for identification and arbitrarily primed PCRs (AP-PCRs) to determine various MS genotypes.

Results:

From birth to six months of age, 30 per cent of children exhibited MS colonization, and by the age of 30 months, 100 per cent harboured the bacteria (P < 0.001). Factors associated with MS colonization were eruption of teeth (P < 0.001), feeding habits with mean colony count being significantly lower in breast-fed as compared to bottle-fed children (P < 0.001) and a significant association between mean MS count of child and mother's practice of sharing spoon with child (P < 0.001). The AP-PCR fingerprinting profile analysis showed 17 MS groups (clusters) containing identical or highly related isolates in mother-child pairs with a high level of similarity (77.27 %).

Interpretation & conclusions:

The presence of matching MS genotypes suggested vertical transmission from mothers to children. Feeding habits, gum cleaning and number of erupted teeth in children had significant effect on MS colonization. There is a need to develop strategies to present MS colonization in children.
Presence of metallo-beta-lactamases (MBL), extended-spectrum beta-lactamase (ESBL) & AmpC positive non-fermenting Gram-negative bacilli among Intensive Care Unit patients with special reference to molecular detection of bla CTX-M & bla AmpC genes
Authors: Gupta Richa , Malik Abida , Rizvi Meher , Ahmed Moied
Published: December 2016

Background & objectives:

Non-fermenting Gram-negative bacilli (NFGNB) including Pseudomonas aeruginosa and Acinetobacter baumannii have been implicated in a variety of infections, particularly in the Intensive Care Units (ICUs). This study was aimed to overview the burden of multidrug-resistant NFGNB causing infections in ICU and also to assess the occurrence of extended-spectrum beta-lactamases (ESBLs), AmpC and metallo-beta-lactamases (MBLs) among these isolates.

Methods:

Bacterial culture, identification and antibiotic susceptibility were carried out. ESBLs and AmpC were detected both phenotypically and genotypically. MBL was detected by modified Hodge and imipenem-ethylenediaminetetraacetic acid double-disc synergy test.

Results:

NFGNB represented 45 (37%) of total 121 Gram negative isolates. Multidrug resistance was observed in 66.9 per cent and 72.5 per cent isolates of P. aeruginosa and A. baumannii, respectively. Detection by phenotypic methods showed presence of ESBL, AmpC and MBL in 21.4, 51.1 and 21.4 per cent isolates, respectively. When detected genotypically by polymerase chain reaction, ESBL and AmpC were detected in 21.4 and 41.4 per cent of NFGNB isolates, respectively. Bla
CTX-M (21.4%) was the most prevalent gene responsible for ESBL production.

Interpretation & conclusions:

Most of the NFGNB isolated from ICU patients were multidrug-resistant and producers of ESBL, AmpC and MBL. A regular surveillance is required to detect ESBL, AmpC and MBL producers, especially in ICU patients.
Performance of the 2010 American College of Rheumatology/European League against Rheumatism (ACR/EULAR) criteria for classification of rheumatoid arthritis in an Indian population
Authors: Kedar M. V. V. Pavan , Acharya Raviraja V. , Prakashini K.
Published: December 2016

Background & objectives:

The 1987 American College of Rheumatology (ACR) criteria were criticised for classifying patients only in the late stage. The 2010 ACR/European League against Rheumatism (ACR/EULAR) classification criteria for rheumatoid arthritis (RA) were thus formulated to recognize the early stage of disease with high sensitivity. This pilot study was designed to estimate and compare the sensitivities of the 1987 ACR and 2010 ACR/EULAR classification criteria for RA.

Methods:

In a tertiary care hospital, the medical records of 97 patients diagnosed with RA were reviewed. Case study forms were filled with relevant clinical data and investigation results after reviewing each medical record. The radiographs of hands were also reviewed. To each case, both the 1987 ACR and the 2010 ACR/EULAR criteria were applied and the results of the classification were noted.

Results:

The sensitivity of the 2010 ACR/EULAR criteria was found to be 79.38 per cent [95% confidence interval (CI) = 71.33-87.43%] and the sensitivity of the 1987 ACR criteria was found to be 63.92 per cent (95% CI = 54.36-73.48%). The difference in the sensitivities was significant (P< 0.01). There was a significant rise in sensitivity of the 2010 ACR/EULAR criteria when patients having anti-cyclic citrullinated peptide (CCP) titres were analysed.

Interpretation & conclusions:

The 2010 ACR/EULAR criteria were found to be more sensitive than the 1987 ACR criteria possibly owing to features of the criteria. Anti-CCP titres were found to increase the sensitivity of the 2010 ACR/EULAR criteria.
Validity and Reliability of a Tool to Assess Quality Improvement Knowledge and Skills in Pediatrics Residents
Authors: Doupnik Stephanie K. , Ziniel Sonja I. , Glissmeyer Eric W. , Moses James M.
Published: December 2016

Background 

Residency programs are expected to educate residents in quality improvement (QI). Effective assessments are needed to ensure residents gain QI knowledge and skills. Limitations of current tools include poor interrater reliability and requirement for scorer training.

Objective 

To provide evidence for the validity of the Assessment of Quality Improvement Knowledge and Skills (AQIKS), which is a new tool that provides a summative assessment of pediatrics residents' ability to recall QI concepts and apply them to a clinical scenario.

Methods 

We conducted a quasi-experimental study to measure the AQIKS performance in 2 groups of pediatrics residents: postgraduate year (PGY) 2 residents who participated in a 1-year longitudinal QI curriculum, and a concurrent control group of PGY-1 residents who received no formal QI training. The curriculum included 20 hours of didactics and participation in a resident-led QI project. Three faculty members with clinical QI experience, who were not involved in the curriculum and received no additional training, scored the AQIKS.

Results 

Complete data were obtained for 30 of 37 residents (81%) in the intervention group, and 36 of 40 residents (90%) in the control group. After completing a QI curriculum, the intervention group's mean score was 40% higher than at baseline (P < .001), while the control group showed no improvement (P = .29). Interrater reliability was substantial (κ = 0.74).

Conclusions 

The AQIKS detects an increase in QI knowledge and skills among pediatrics residents who participated in a QI curriculum, with better interrater reliability than currently available assessment tools.
Geriatrics Curricula for Internal and Family Medicine Residents: Assessing Study Quality and Learning Outcomes
Authors: Cheng Huai Yong , Davis Molly
Published: December 2016

Background 

Prior reviews of geriatrics curricula for internal medicine (IM) and family medicine (FM) residents have not evaluated study quality or assessed learning objectives or specific IM or FM competencies.

Objective 

This review of geriatrics curricula for IM and FM residents seeks to answer 3 questions: (1) What types of learning outcomes were measured? (2) How were learning outcomes measured? and (3) What was the quality of the studies?

Methods 

We evaluated geriatrics curricula that reported learning objectives or competencies, teaching methods, and learning outcomes, and those that used a comparative design. We searched PubMed and 4 other data sets from 2003–2015, and assessed learning outcomes, outcome measures, and the quality of studies using the Medical Education Research Study Quality Instrument (MERSQI) and Best Evidence Medical Education (BEME) methods.

Results 

Fourteen studies met inclusion criteria. Most curricula were intended for IM residents in the inpatient setting; only 1 was solely dedicated to FM residents. Median duration was 1 month, and minimum geriatrics competencies covered were 4. Learning outcomes ranged from Kirkpatrick levels 1 to 3. Studies that reported effect size showed a considerable impact on attitudes and knowledge, mainly via pretests and posttests. The mean MERSQI score was 10.5 (range, 8.5–13) on a scale of 5 (lowest quality) to 18 (highest quality).

Conclusions 

Few geriatrics curricula for IM and FM residents that included learning outcome assessments were published recently. Overall, changes in attitudes and knowledge were sizeable, but reporting was limited to low to moderate Kirkpatrick levels. Study quality was moderate.