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The use of biodegradable polymeric scaffolds for tissue regeneration is becoming a common practice in the clinic. Therefore, an inclined trend is developing with regards to improving the mechanical properties of these scaffolds. Here, we aim to improve the mechanical properties of poly (butylene succinate) (PBS)/poly (l-lactic acid) (PLLA) blends by incorporating hydroxyapatite nanoparticles (HAP) in the blends to form composites. PBS/PLLA = 100/0, 95/5, 90/10, 85/15, and 0/100 wt% blends, along-with the loadings of a few mg of HAPs, were prepared using the solution casting method. A scanning electron microscope showed the voids and droplets, indicating the immiscibility of blends. Due to this immiscibility, the tensile strength values of the blends were found to be in between that of pure PBS (42.85 MPa) and pure PLLA (31.39 MPa). HAPs act as a compatibilizer by incorporating themselves in the voids and spaces caused by the immiscibility, thus increasing the overall tensile strength of the resulting composite to a certain extent, e.g., the tensile strength of PBS/PLLA = 95/5 loaded with 50 mg HAPs was found to be 51.16 MPa. The structural analysis employing the X-ray diffraction (XRD) patterns confirmed the formation of polymer blends and composites. The contact angle analysis showed that the addition of HAPs increased the hydrophilicity of the resulting composites. Selective samples were investigated based on mechanical properties to see if the blends and composites are biocompatible. The obtained results showed that all of the samples with better mechanical properties demonstrated good biocompatibility. This indicates the effectiveness of scaffolds for tissue regeneration.

We study the electrically conducting fluid stability of magnetohydrodynamic flow between parallel plates by Chebyshev collocation method by applied transverse magnetic field. Temporal growth is obtained by the governing equations. The results show that the dominating factor is the change in shape of the undisturbed velocity profile caused by the magnetic field, which depends only on the Hartmann number. The stability equations is solved by QZ-algorithm to find the eigenvalue problem. The numerical calculation show that Magnetic field with particular magnitude destabilizes Couette flow while other magnitude stabilize the flow. It is also analyzed that Rec decreases rapidly to the minimum value for Hartmann number Ha greater than 3.887 and increases steadily from Hartmann number Ha (>5.559). It is observed that critical Reynolds number Rec is larger as Hartmann number decreases from Ha=3.887. The two critical Reynolds numbers in the elliptic curves are found for different values of Hartmann number.

This communication explores the effects of homogeneous-heterogeneous reactions in thermally stratified mixed convection flow of an Oldroyd-B fluid. Flow situation is addressed when the diffusion coefficients of the reactant and auto catalyst are equal. The stagnation point flow towards a stretching surface is discussed. Mathematical equations are developed for velocity, temperature and concentration functions through boundary layer theory. Resulting differential systems are computed for the convergent series solutions. Influences of various pertinent variables on the velocity, temperature and concentration are discussed. Comparison of present study is shown with the previous results. The outcomes are found in very good agreement. Keywords: Homogeneous-heterogeneous reactions, Thermally stratified fluid, Mixed convection, Stagnation point, Oldroyd-B fluid

Lexisearch and genetic algorithms are two different types of methods for solving combinatorial optimization problems. Lexisearch algorithm gives us exact optimal solution, whereas, genetic algorithms give heuristic solution to a problem. In this paper, a hybrid algorithm (LSGA) that combines lexisearch and genetic algorithms is developed to obtain heuristic solution to the quadratic assignment problem. The proposed algorithm uses lexisearch algorithm to generate initial population, self-adaptively three crossover operators, and randomly one of four mutation operators, restricted combined mutation operator as local search, and multi-parent sequential constructive crossover as immigration method. The self-adaptive crossover operator that consists of one-point crossover, swap path crossover and sequential constructive crossover can produce better solutions. Also, the random selection of a mutation operator effectively prevents LSGA from being stuck in local optimal zone. Further, the immigration method with combined mutation effectively generated very good chromosomes, which promotes the convergence rate and accuracy of the solution. Experimental results on four categories of benchmark QAPLIB instances show the effectiveness of the LSGA. Out of 35 instances 18 instances have been solved optimally, and for the remaining instances, solutions are very close to the optima. Finally, a comparative study has been carried out between LSGA and unified particle swarm optimization (UPSO) for the same instances. In terms of solution quality, LSGA outperformed UPSO for all category of instances. Also, in terms of computational time, except for seven instances, LSGA outperformed UPSO.

Tomato (Solanum lycopersicum L.) is an important vegetable crop cultivated in the tropical and sub-tropical regions of the world. Low productivity in India is due to occurrence of both biotic and abiotic stresses. Among the biotic stresses, tomato leaf curl disease, bacterial wilt, early blight and Groundnut Bud Necrosis Virus disease have become serious production constraints causing considerable yield loss in the major tomato growing areas of the country. Adoption of multiple disease resistant varieties or F1 hybrids would be the most appropriate way to address these diseases. At ICAR-IIHR, Bengaluru systematic breeding strategies were employed to pyramid genes for resistance to early blight, bacterial wilt and tomato leaf curl diseases and to develop advanced breeding lines& F1 hybrids with triple disease resistance. Stable source of resistance to early blight and bi-partite begomo-virus (Tomato Leaf Curl New Delhi Virus) has been identified in Solanum habrochaites LA-1777. Validation with molecular markers linked to tomato leaf curl virus resistance revealed that LA-1777 carryTy2 and other putative resistant genes. Several high yielding dual purpose hybrids were also developed for fresh market and processing with high level of resistance to multiple diseases. Cherry tomato lines have also been bred for high TSS, total carotenoids, total phenols, flavonoids, vitamin C, acidity and lycopene content. IIHR-249-1, IIHR-2101 (Solanum habrochaites LA-1777), IIHR- 2866 and IIHR-2864 recorded high values for quality parameters like total carotenoids, lycopene, vitamin C, total phenols, flavonoids and TSS. Drought tolerant root stock has been developed by an interspecific cross between S. habrochaites LA-1777 and S. lycopersicum (15 SB SB). Resistant sources have also been identified against Tuta absoluta, a serious insect pest reported from major tomato growing areas in the country in recent time. High temperature tolerant breeding lines are in pipe line.

In this study, adsorption of hexavalent chromium has been examined on ZIF-8 and its various composites. ZIF-8 was modified by using amine groups, GO and Mg(OH) _2 /GO. ZIF-8, Mg(OH) _2 /GO, ZIF-8/NH _2 , ZIF-8/Mg(OH) _2 /GO, ZIF-8/NH _2 /GO and ZIF-8/NH _2 /Mg(OH) _2 /GO was studied for Cr(VI) adsorption Several characterization techniques were used for the structural and surface characterization such as Fourier transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), scanning electron microscopy (SEM), and Brunauer–Emmett–Teller (BET) surface area analyzer. The impact of various adsorption parameters (contact time, pH, initial concentration of Cr(VI) and absorbent dosage) was studied in batch experiments. Different kinetic and isotherm models were applied on equilibrium data. The adsorption process of ZIF-8 and its composites was explained by pseudo-second-order kinetic model as well as Langmuir isotherm, with maximum removal efficiency of 98% for Cr(VI) by ZIF-8/NH _2 /Mg(OH) _2 /GO.

A new methodology involving the use of Bovine Serum Albumin (BSA) as a probe and liquid crystal (LC) as a signal reporter for the detection of heavy metal ions in water at neutral pH was developed. BSA acted as a multi-dentate ligand for the detection of multiple metal ions. The LC sensor was fabricated by immobilizing 3 µg mL−1 BSA solution on dimethyloctadecyl-[3-(trimethoxysilyl)propyl]ammonium chloride (DMOAP)-coated glass slides. In the absence of heavy metal ions, a dark optical image was observed, while in their presence, a dark optical image turned to bright. The optical response was characterized by using a polarized optical microscope (POM). The BSA based LC sensor selectively detected toxic metal ions as compared to s block metal ions and ammonium ions in water. Moreover, the limit of detection was found to be very low (i.e., 1 nM) for the developed new biosensor in comparison to reported biosensors.

Perovskite based solar cells have demonstrated impressive performances. Controlled environment synthesis and expensive hole transport material impede their potential commercialization. We report ambient air synthesis of hole transport layer free devices using ZnO-GO as electron selective contacts. Solar cells fabricated with hole transport layer free architecture under ambient air conditions with ZnO as electron selective contact achieved an efficiency of 3.02%. We have demonstrated that by incorporating GO in ZnO matrix, low resistivity electron selective contacts, critical to improve the performance, can be achieved. We could achieve max efficiency of 4.52% with our completed devices for ZnO: GO composite. Impedance spectroscopy confirmed the decrease in series resistance and an increase in recombination resistance with inclusion of GO in ZnO matrix. Effect of temperature on completed devices was investigated by recording impedance spectra at 40 and 60 oC, providing indirect evidence of the performance of solar cells at elevated temperatures.

Synthesis of hydroazulene derivatives has been carried out through a ring-enlargement route by using carbene adduct intermediates. The protocol can be applied for the construction of functionalized hydroazulene skeletons as key components of many natural products as well as the core system of novel liquid-crystalline materials.

New liquid-crystalline materials with a perhydroazulene core were synthesized and the stereochemistry of these compounds was investigated. The mesomorphic properties of the new LC compounds were investigated by differential scanning colorimetry, polarizing optical microscopy and X-ray diffraction. We report here on the LC properties of nonchiral materials, which predominantly exhibit smectic phases and display nematic phases only within narrow temperature ranges. The dependence of the mesogenic behavior of the new materials on the stereochemistry of the core system was also investigated. All newly synthesized compounds were fully characterized by the usual spectroscopic and analytical methods.

Devastating floods adversely affect human life and infrastructure. Various regions of the Hindukush-Karakoram-Himalayas receive intense monsoon rainfall, which, together with snow and glacier melt, produce intense floods. The Kabul river basin originates from the Hindukush Mountains and is frequently hit by such floods. We analyses flood frequency and intensity in Kabul basin for a contemporary period (1981–2015) and two future periods (i.e., 2031–2050 and 2081–2100) using the RCP4.5 and RCP8.5 scenarios based on four bias-corrected downscaled climate models (INM-CM4, IPSL-CM5A, EC-EARTH, and MIROC5). Future floods are modelled with the SWAT hydrological model. The model results suggest an increasing trend due to an increasing precipitation and higher temperatures (based on all climate models except INM-CM4), which accelerates snow and glacier-melt. All of the scenario results show that the current flow with a 1 in 50 year return period is likely to occur more frequently (i.e., 1 in every 9–10 years and 2–3 years, respectively) during the near and far future periods. Such increases in intensity and frequency are likely to adversely affect downstream population and infrastructures. This, therefore, urges for appropriate early precautionary mitigation measures. This study can assist water managers and policy makers in their preparation to adequately plan for and manage flood protection. Its findings are also relevant for other basins in the Hindukush-Karakoram-Himalayas region.

This article examines the effects of homogeneous-heterogeneous reactions and Newtonian heating in magnetohydrodynamic (MHD) flow of Powell-Eyring fluid by a stretching cylinder. The nonlinear partial differential equations of momentum, energy and concentration are reduced to the nonlinear ordinary differential equations. Convergent solutions of momentum, energy and reaction equations are developed by using homotopy analysis method (HAM). This method is very efficient for development of series solutions of highly nonlinear differential equations. It does not depend on any small or large parameter like the other methods i. e., perturbation method, δ-perturbation expansion method etc. We get more accurate result as we increase the order of approximations. Effects of different parameters on the velocity, temperature and concentration distributions are sketched and discussed. Comparison of present study with the previous published work is also made in the limiting sense. Numerical values of skin friction coefficient and Nusselt number are also computed and analyzed. It is noticed that the flow accelerates for large values of Powell-Eyring fluid parameter. Further temperature profile decreases and concentration profile increases when Powell-Eyring fluid parameter enhances. Concentration distribution is decreasing function of homogeneous reaction parameter while opposite influence of heterogeneous reaction parameter appears.

Aim: The present study was to evaluate the space provided for the temporary luting cement, after the application of various coats of die spacers, during the fabrication of provisional crowns and bridges. Materials and Methods: A total of 50 specimens of dental stone with provisional crowns on all these samples were prepared and were divided into five groups based on the application of various coats of different die spacers. Later these specimens were sectioned buccolingually and were observed using a stereomicroscope under 100X magnification. The images thus obtained were evaluated and noted for the amount of space between the inner surface of the provisional crown and the specimens at five different locations using Image Pro 6.0 Express software and the values were subjected to one-way ANOVA test, and unpaired t-test. Results: There was a significant increase of luting space thickness with various die spacer applications than the specimens of control group. Conclusion: Specimens of double coat applications of silver and gold die spacers showed higher luting cement space than the separating media application specimens.

The ordered clustered travelling salesman problem is a variation of the usual travelling salesman problem in which a set of vertices (except the starting vertex) of the network is divided into some prespecified clusters. The objective is to find the least cost Hamiltonian tour in which vertices of any cluster are visited contiguously and the clusters are visited in the prespecified order. The problem is NP-hard, and it arises in practical transportation and sequencing problems. This paper develops a hybrid genetic algorithm using sequential constructive crossover, 2-opt search, and a local search for obtaining heuristic solution to the problem. The efficiency of the algorithm has been examined against two existing algorithms for some asymmetric and symmetric TSPLIB instances of various sizes. The computational results show that the proposed algorithm is very effective in terms of solution quality and computational time. Finally, we present solution to some more symmetric TSPLIB instances.