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This article presents the phases in a life cycle assessment (LCA) methodology and gives the design approach for two types of retaining walls namely, conventional reinforced concrete retaining wall (cantilever type) and a mechanically stabilised earth (MSE) wall using paragrid 100/05 as reinforcement. A comparative study was done for both retaining structures with three different heights of wall, such as 3 m, 5 m and 7 m. All the retaining walls are designed using a FEM-based GEO5 software and are checked for their stability, keeping the design economical. Later, GaBi software was used to evaluate the environmental impacts using eight mid-point category indicators, such as cumulative energy demand, global warming potential, acidification potential, water use, ozone depletion potential, eutrophication potential, land use, and particulate matter. Later, an evaluation based on economic point of view was also carried out. Potential impact on environment indicated that, the global warming potential, acidification potential, and fine particulate formation are influenced primarily by concrete and steel production (due to their raw mineral extraction, cleaning and refining, and energy invested for processing), as well as by the fuel used for transportation, and on-site machinery. It was found that, MSE wall is more environment friendly than conventional reinforced concrete cantilever retaining wall, as it resulted in 24% lower environmental impact for a 3 m height wall and 60% lower environmental impact for 5 m and 7 m height walls. Economic evaluation of both retaining structures revealed that, the MSE wall is proved to be approximately 42% less in cost for 3 m height wall and about 70% less cost for 5 m as well as 7 m height walls. In terms of environmental and economic aspects, MSE wall is found to be more sustainable than the cantilever retaining wall over its full life cycle. [ABSTRACT FROM AUTHOR]

The present paper investigates the stabilization of Mg-3Ca alloy and Mg-3Ca/SiC/5p composite foams with and without the addition of 0.12 wt.% beryllium. In Mg-3Ca alloy foam, Be addition has shown a significant improvement in the expansion and pore structure. Whereas, in case of Mg-3Ca/SiC/5p composite foams, the SiC particles stabilized the foam effectively, while Be addition does not show any distinguishable improvement in the foam structure. The formation of BeO and the dense coverage of SiC particles in the gas–solid interface of Mg-3Ca and Mg-3Ca/SiC/5p composite foams, respectively, are the reasons for the foam stabilization. Mg-3Ca/SiC/5p composite foam exhibited lowest foam density of 0.10 g/cm3. The quasi-static compression test shows that Mg-3Ca-0.12Be/SiC/5p composite foam containing Be exhibited lower foam density and higher normalized compressive strength. The energy absorption capacity per unit foam density in Be containing foams was also higher. [ABSTRACT FROM AUTHOR]

Friction stir welding (FSW) produce a strong metallurgical joint with the application of severe deformations and frictional heating in the metals and alloys by using a non-consumable rotating tool consisting of pin and tool shoulder. During welding, the plastic deformations of base metals vary for the varying mechanical properties such as tensile strength (TS), impact strength (IS), and hardness (HV) which inturn varies the welding conditions and parameters. Therefore, selection of optimal weld parameters plays an important role in enhancing the quality of weld joint.In this article, friction stir butt welds made of 6061and 7075 Al alloys are performed with various welding parameters such as rotational speed of tool, angle of tilt, and axial force using tool has taper pin profile. Experimentsare carried out on twenty-seven joints that are made on 6061 and 7075 Al Alloy plates of 6.50 mm thick of same nature and tested for its tensile, impact and HV properties. [ABSTRACT FROM AUTHOR]

Case: We present a case of 19-year-old male patient with right sided comminuted metadiaphyseal distal femur fracture. Fixation was done using distal femur condylar locking plate. Washers were used with the screws to shimming the plate to achieve the coronal alignment and prevent stress over the screws. 2-year follow-up shows good alignment, radiological union and functional outcome without any complications. "Shimming" a locking plate with washers helps to achieve the better coronal alignment in comminuted metadiaphyseal distal femur fractures with coronal malalignment. It reduces the stress over screws and prevents implant-related complications. [ABSTRACT FROM AUTHOR]

High-velocity oxy-fuel (HVOF) is a widely used thermal spray technique to obtain high density, high bond strength, and improved hardness coatings. In the present work, optimization of HVOF process parameters was carried out using the Taguchi method to minimize porosity and improve microhardness, and bond strength of Cr2O3 coatings. Based on the signal-to-noise ratio and analysis of variance, the significance of each process parameter and optimum parameter combination is obtained. Based on the signal-to-noise ratio, the most significant process parameter affecting porosity and microhardness was standoff distance, while for bond strength, it was powder feed rate. An optimal combination of process parameters for porosity, microhardness, and bond strength was obtained from S/N ratio analysis. For porosity, optimal parameters were standoff distance of 100 rpm, powder feed rate of 30 g/min, and gun speed of 250 mm/s. The optimal process parameters for microhardness were standoff distance of 300 rpm, powder feed rate of 50 g/min, and gun speed of 200 mm/s. Finally, for bond strength, the optimal process parameters were standoff distance of 300 rpm, powder feed rate of 50 g/min, and gun speed of 250 mm/s. Statistical results for porosity, microhardness, and bond strength showed that the difference between the predicted R2 and adjusted R2 values were relatively minimal and close to the one highlighting the fitness of the regression model employed for analysis. Fracture analysis after bond strength test showed combined adhesion/cohesion type failure for the Cr2O3 coatings. [ABSTRACT FROM AUTHOR]

Background: Fractures of the proximal humerus represent approximately 4% of all fractures and 26% of humerus fractures. Proper reduction, stable internal fixation and early initiation of physiotherapy help to achieve a good functional outcome. Aim of this study was to evaluate varus fixation/malunion of proximal humerus fractures and its relation to functional outcome. Materials and Methods: We retrospectively evaluated 32 patients with proximal humerus fractures who were surgically treated between 2015 and 2017 at tertiary care hospital. We divided the patients into three groups on the basis of the neck-shaft angle as valgus group, normal group and varus group to observe the influence of neck-shaft angle on efficacy. Patients were evaluated for functional outcome using the Constant–Murley score. Results: Two-part fractures had better functional outcome (Constant score = 75.15) compared to three parts with the moderate functional outcome (Constant score = 68.81) and the four-part fracture had poor functional outcome (Constant score = 52.66). After 6 months of follow-up, 13 patients had a neck-shaft angle of less than 126°. The functional outcome is significantly better among patients with normal neck-shaft angle and had a mean Constant score of 76.63 as compared to patients with varus deformity had a mean Constant score 60 (p = 0.001). 10 patients did not have medial support, in which 08 patients had neck-shaft angle less than 126° and 2 had a normal neck-shaft angle. Conclusion: High fracture comminution, improper restoration of medial continuity causes varus deformity of the humeral head and it leads to poor functional outcome. The small sample size is the limitation of our study. [ABSTRACT FROM AUTHOR]

The present work reports on foaming of magnesium alloys and composites using MgCO3 as the blowing agent. Foaming was done via the molten metal route by direct addition of MgCO3 in molten Mg. The alloys and composites required for foaming were prepared by varying the concentration of aluminum (10 to 30 wt pct) and calcium (0 and 2 wt pct) in Mg. SiC of 10-µm size and about 10 to 20 vol pct was added as reinforcement particles in the composite. The liquidus temperature of the alloys and composites, the decomposition behavior of MgCO3, and the intrinsic oxides that formed in the melt have a significant effect on the structure of the foams. Mg alloys and composites with 30 wt pct Al showed better foaming behavior with higher expansion, lower density, good cell structure, and uniform cell size distribution due to the smaller difference between their liquidus temperature and the decomposition temperature of MgCO3. The addition of 2 wt pct Ca showed a significant effect on foaming, and the MgO and MgAl2O4 (spinel) particles formed in situ in the molten Mg during foaming acted as the stabilizing agents. [ABSTRACT FROM AUTHOR]

Application of growth factors at wound site has improved the efficiency and quality of healing. Basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) induce proliferation of various cells in wound healing. Delivery of growth factor from controlled release systems protect it from degradation and also result in sustained delivery of it at the site of injury. The goal of the study was to develop a Polyethylene glycol (PEG) cross-linked cotton-like chitosan scaffold (CS-PEG-H) by freeze-drying method and chemically conjugate heparin to the scaffold to which the growth factors can be electrostatically bound and evaluate its wound healing properties in vitro and in vivo. The growth factor containing scaffolds induced increased proliferation of HaCaT cells, increased neovascularization and collagen formation seen by H and E and Masson's trichrome staining. Immunohistochemistry was performed using the Ki67 marker which increased proliferation of cells in growth factor containing scaffold treated group. Frequent dressing changes are a major deterrent to proper wound healing. Our system was found to release both VEGF and bFGF in a continuous manner and attained stability after 7 days. Thus our system can maintain therapeutic levels of growth factor at the wound bed thereby avoiding the need for daily applications and frequent dressing changes. Thus, it can be a promising candidate for wound healing. [ABSTRACT FROM AUTHOR]

SmxBi3–xTiNbO9 (SBTN) with x = 0 , 0.2, 0.4, 0.6, 0.8 and 1.0, a novel type of ceramic was prepared by a conventional solid-state reaction method. X-ray diffraction patterns confirm the formation of a single-phase, and lattice parameters were calculated based on the parent compound Bi3TiNbO9 (BTN). Well-defined grains were seen in the scanning electron microscopy pictures. A kink observed near 400°C for all the samples in the dielectric plot as well as in the stretched exponential parameter (β) vs. temperature plot reveals the dielectric relaxation of the samples. The tolerance factor (t) was found to increase with increase in the size of the A-site (Bi-site) modified ion (Sm). Impedance and modulus spectroscopic studies were conducted to understand the plausible reason for the dielectric relaxation. The relaxation was found to be well-fit with Arrhenius equation. SBTN samples showed lower dielectric loss compared to BTN. The remnant polarization, obtained from experimental, was found to be less than that of theoretically calculated polarization, using Shimakawa's formula. The proposed defect mechanism was interpreted using FTIR and Raman spectroscopic studies. [ABSTRACT FROM AUTHOR]

Endocardial endothelium, which lines the chambers of the heart, is distinct in its origin, structure, and function. Characterization studies using genomics and proteomics have reported molecular signatures supporting the structural and functional heterogeneity of various endothelial cells. However, though functionally very important, no studies at protein level have been conducted so far characterizing endocardial endothelium. In this study, we used endothelial cells from pig heart to investigate if endocardial endothelial cells are distinct at the proteome level. Using a high-throughput liquid chromatography-tandem mass spectrometry for proteome profiling and expression, we identified sets of proteins that belong to specific biological processes and metabolic pathways in endocardial endothelial cells supporting its specific structural and functional roles. The study also identified several transcription factors and cell surface markers, which may have roles in the specificity of endocardial endothelium. The detection of sets proteins preferentially expressed in endocardial endothelium offers new insights into its role in the regulation of cardiac function. Data are made available through ProteomeXchange with identifier PXD009194. [ABSTRACT FROM AUTHOR]

The dearth of proper delineation for energy sorghum cultivation has led to a prerequisite for evaluation and identification of test environments for the newly developed lines. This becomes of vital importance as the biomass yield is highly influenced by genotype and environmental (G × E) interactions. Several agronomic traits were considered to assess the biomass yield and the combined analysis of variance for G (genotype), L (location) and interaction effect of G × L. The variations in the yield caused by the interaction of G × L are very essential to acquire knowledge on the specific adaptation of a genotype. Thus, the multi-location trials conducted across locations and years have helped to identify the stable environments with specific adaptation for biomass sorghum. The presence of close association between the test locations suggested that the same information about the genotypes could be obtained from fewer test environments, and hence the potential to reduce evaluation costs. The two genotypes—IS 13762 and ICSV 25333—have shown stable performance for biomass traits across all the locations, in comparison with CSH 22SS (check). The top ten entries with stable and better performance for fresh biomass yield, dry biomass yield, grain yield and theoretical ethanol yield were ICSV 25333, IS 13762, CSH 22SS, IS 25302, IS 25301, IS 27246, IS 16529, DHBM2, ICSSH 28 and IS 17349. [ABSTRACT FROM AUTHOR]

Lead-free piezoelectric ceramic composites (1-x) Na 0.5Bi 0.5TiO 3-xSrTiO 3, where x = 0.05, 0.10, 0.15 and 0.2, are prepared by mixing independently-prepared individual phases through sol–gel method. X-ray diffraction revealed the coexistence of rhombohedral and cubic phases. Surface morphology of the composites is observed using SEM, and both the phases are observed in the samples. Spectroscopic studies of the composites are characterized based on Fourier transform infrared, and vibration bands are analyzed at room temperature in the wave number region 500–3,000 cm −1. Dielectric properties of these composites are measured from room temperature to 400 °C in the frequency range 1–10 kHz, and these studies indicate the presence of defect clusters within the composite materials. P–E hysteresis loops of these samples were measured as a function of temperature and observed large anomalies in the behavior compared to pure sodium bismuth titanate (NBT) (the host material). Unlike NBT, all the composites exhibited excellent P–E loops. In addition, decrease in remanence polarization is observed, with increase of SrTiO 3 at room temperature. Piezoelectric parameter d 33 is measured on poled composites. [ABSTRACT FROM AUTHOR]

The effect of TiAl3 particle size and distribution on their settling and dissolution behaviour in molten aluminium during grain refinement has been studied. For this purpose Al–5Ti master alloys containing blocky TiAl3 particles of different size and distribution are synthesised at reaction temperatures 750, 800 and 850 °C for 60 min and used for grain refinement. The extent of fading and the recovery due to stirring is calculated from the measured grain size and used to judge the dissolution and settling behaviour of TiAl3 in molten Al, which is greatly attributed to its size and distribution in Al–5Ti master alloy. Fine TiAl3 particle dissolve faster in the melt and cause fading. Larger size TiAl3 particles exist for longer time in molten Al and act as a nucleating site even when added in hypoperitectic concentration (0.05 wt% Ti). [ABSTRACT FROM AUTHOR]

An investigation into the effect of ternary alloying element additions such as copper, magnesium, manganese, zinc, and nickel on pore formation in cast Al-12.6-wt pct Si eutectic alloy by employing a novel pore characterization technique is reported here. In this approach, the low-pressure testing method was combined with the metal foam manufacturing technique of intentionally adding TiH2, which enhances hydrogen pore formation and offers a method to distinguish the effect of individual alloying elements on hydrogen porosity formation. [ABSTRACT FROM AUTHOR]

Effect of doping in Na0.5Bi0.5TiO3 (NBT) with Ce3+ and Sm3+ at the A-site on dielectric behaviour, impedance and conductivity is being reported. Na0.5Bi0.5-xAxTiO3 samples (A being Ce and Sm) are studied with varying values of x. For Na0.5Bi0.5-xCexTiO3 samples x is 0.001, 0.005 and 0.007 and for Na0.5Bi0.5-xSmxTiO3 samples x is 0.05, 0.1 and 0.15. Dielectric constant and loss are studied in the frequency range 10 kHz to 1 MHz and in the temperature range 30-650°C. Impedance and electric modulus studies are undertaken. The relaxations observed in the samples are non-Debye and activation energies for relaxation and conduction are evaluated. [ABSTRACT FROM AUTHOR]

Electrical conduction studies on Ba(Nd0.2Ti0.6Nb0.2)O3 ceramic samples prepared through conventional and microwave sintering route are presented in this paper. D.C. and a.c. conductivities of these samples as a function of temperature from 300--900 K have been studied. Two types of conduction processes are evident from the frequency dependant conductivity plots, i.e. low-frequency conduction due to short-range hopping and high-frequency conduction due to the localized relaxation (reorientational) hopping mechanism. Grain and grain boundary contributions to the conductivity in these samples are obtained from impedance/admittance measurements via equivalent circuit modelling. [ABSTRACT FROM AUTHOR]

Dielectric data of new [ Ba (Nd x Ti 1 - 2 x Nb x) O 3 ] 0.30 [ Na 0.5 Bi 0.5 TiO 3 ] 0.70 ( x = 0.075 ) relaxor ceramic was modelled using a new modified Lorentz equation (T and ω simultaneously) as proposed by us. The activation energy for thermally activated orientation of dipoles and relaxation times were estimated. Dielectric resonance and anti-resonance data as a function of temperature and angular frequency of other piezoelectric compound [ Ba (Nd 0.1 Ti 0.8 Nb 0.1) O 3 ] 0.35 [ (Na 0.5 Bi 0.5) TiO 3 ] 0.65 was also modelled using the modified Lorentz equation as proposed by us. It is shown that using this equation, it is possible to obtain the polarizability, piezoelectric charge constant, piezoelectric voltage constant and activation energy for resonance and anti-resonance. [ABSTRACT FROM AUTHOR]

Dielectric, conductivity and piezoelectric properties have been studied on (Ba0.997Nd0.003)TiO3 ceramic samples prepared through microwave sintered (MWS) and conventional sintered (CS) routes and the results are presented in this paper. The room temperature dielectric constant at 10 kHz for CS and MWS samples are 1245 and 5250 respectively. Room temperature dielectric constant in MWS sample was almost four times higher than that of the CS sample. The value of Kt is found to be 0.998 and 0.997; whereas the value of d33 is 7.72nmV-1 (573 K) and 444.66nmV-1 (573 K) for CS and MWS samples, respectively. In the present study almost 57 times enhancement in piezoelectric charge constant (d33) is observed for the MWS Ba0.997Nd0.003TiO3 ceramic when compared to the CS ceramic. [ABSTRACT FROM AUTHOR]