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Fretting wear characteristics of Ti 3 SiC 2 reinforced with 1%, 3%, 5%, 10% and 15% graphene nanoplatelets (GNP) are presented in this paper. Ti 3 SiC 2 /GNP composite was developed using spark plasma sintering at a temperature of 1200 °C. The tests were conducted to investigate the effect of GNPs on the tribological properties of Ti 3 SiC 2 ·Ti 3 SiC 2 /GNP composites fabricated through spark plasma sintering. Higher densification was obtained, resulting in higher values of Vickers Microhardness in the case of spark plasma sintered Ti 3 SiC 2 /GNP, as compared to Ti 3 SiC 2. The friction coefficient and wear rate of GNP reinforced Ti 3 SiC 2 composites were significantly improved, as compared to virgin Ti 3 SiC 2. The composite with 15% GNP showed the lowest friction coefficient of 0.1416 and a wear rate of 5 × 10−5 mm3/Nm, whereas virgin Ti 3 SiC 2 showed a higher coefficient of friction and wear rate of 0.3264 and 17.22 × 10−4 mm3/Nm, respectively. Although the formation of the oxide film was observed on the wear track, however, adhesive and delamination wear were observed as dominant wear mechanisms. The spark plasma sintering proved to be the most effective technique for increasing hardness and tribological properties of Ti 3 SiC 2 /GNP composite. [ABSTRACT FROM AUTHOR]

• Effect of tensile pre-strain on LCF 6061 and 2024 aluminium alloys is studied. • Tensile pre-strain caused a mixed softening/hardening behaviour. • Full relaxation of mean stress occurred only at higher strain amplitudes. • Fatigue lifetime decreased with increasing tensile pre-strain. The present study attends to the effect of tensile pre-strain histories and strain ratio on cyclic deformation behavior of 6061 aluminum alloy and 2024 aluminum alloy. Low-cycle fatigue tests performed in this study covered two areas; Under fully reversed conditions, with 8% tensile pre-strain, 4% tensile pre-strain, and 0% tensile pre-strain, at strain amplitudes varying in the range 0.6–1.75%; Under strain-controlled circumstances at three different strain ratios [−1, 0, and 0.5] with strain amplitudes varying in the range 0.60–1.75%. The outcomes indicate that the material demonstrates a cyclic strain-softening behavior whose degree rises with rising values of strain ratio and reducing values of strain amplitude. The material demonstrates a non-Masing behavior for higher strain amplitudes amid the interval [1.00%−1.75%]. The material demonstrates a nearly-Masing behavior for lower strain amplitudes amid the interval [0.6%−0.85%]. Under non-zero mean strain, a total relaxation of mean stress is observed at higher strain amplitudes, whereas at lower strain amplitudes, no such behavior is observed. [ABSTRACT FROM AUTHOR]

Summary: Adherence to the prescribed anti-tuberculosis drug (ATD) treatment is crucial for curing patients with active TB. Anti-tuberculosis drug (ATD) induced hepatotoxicity (ATDH) may contribute to ATD's poor compliance in patients with tuberculosis (TB) as interruption of treatment and the switch to second-line anti-tuberculosis drugs, which is required in patients who do not tolerate standard drugs, may result in a sub-optimal treatment response. Isoniazid (INH) is a part of ATD and involved with ATDH due to toxic metabolites produced on its metabolism in liver, attributed to the variation in enzymes involved in this pathway like N-acetyltransferase 2 (NAT2), cytochrome P4502E1 (CYP2E1) and glutathione S-transferases (GSTs). The present study aimed at analysis of polymorphism at three loci of NAT2, two loci of GST and one locus on CYP2E1 and development of ATDH in patients undergoing ATD therapy. A total of 408 newly diagnosed patients with tuberculosis were enrolled for this study and at the end of sampling, 17 ATDH cases and 391 non-ATDH cases were reported. The genetic polymorphisms of the NAT2 and CYP2E1 genes were studied by PCR-RFLP and GSTM1 and GSTT1 were evaluated by multiplex PCR. Slow phenotype of NAT2 was found to be a risk factor for developing ATDH when compared to fast acetylators. Slow haplotype C481A590G857 and an intermediate acetylator haplotype T481A590G857 were found to be significantly associated with development of ATDH. GSTM1 and GSTT1 double null genotype was also reported to be associated with ATDH development. The heterozygote genotype ‘c1c2’ of CYP2E1 was also seen to contribute towards elevated risk of ATDH. ‘c2’ allele absence in females ATDH group can be considered as a protective factor against development of ATDH. In males, presence of ‘c1c2’ allele was seen to contribute towards elevated risk of ATDH development. [Copyright &y& Elsevier]

Abstract: Bacillus coagulans RCS3 isolated from hot water springs secreted five isozymes i.e. β-gal I–V of β-galactosidase. β-gal III isozyme was purified using DEAE cellulose and Sephadex G 100 column chromatography. Its molecular weight characterization showed a single band at 315kD in Native PAGE, while two subunits of 50.1 and 53.7kD in SDS PAGE. β-Gal III had pH optima in the range of 6–7 and temperature optima at 65°C. It preferred nitro-aryl-β-d-galactoside as substrate having K m of 4.16mM with ONPG. More than 85% and 80% hydrolysis of lactose (1–5%, w/v) was recorded within 48h of incubation at 55°C and 50°C respectively and pH range of 6–7. About 78–86% hydrolysis of lactose in various brands of standardized milk was recorded at incubation temperature of 50°C. These results marked the applications of β-gal III in processing of milk/whey industry. [Copyright &y& Elsevier]

Abstract: Agricultural residues are spatially scattered in Punjab. The spatial distribution and associated costs on collection and transportation of this resource are the critical factor in planning the biomass based power plants. This paper presents a case study of Bathinda district of Punjab, using geographical information system to evaluate the feasibility of setting up biomass based power plants and optimizing their location. Mathematical models were developed to determine the storage and handling cost of agricultural residue. Geographical information system and non-linear optimization techniques were employed to locate appropriate sites and sizes of power plants. It was found that two power plants and their two collection centres are financially feasible. Power generation capacity is 20 MW (e). The fuel procurement area was in the range of less than 20 km. [Copyright &y& Elsevier]

Abstract: In Punjab, million of tons of agricultural biomass are being generated every year, but it is spatially scattered. The spatial distribution of this resource and the associated costs on collection and transportation are the major bottleneck in the success of biomass energy-conversion facilities. This paper deals with the mathematical model for collection and transporting the biomass from fields to biomass based power plant. The unit transport cost was calculated by using this model. Four systems of transport were conceptualized for two transport modes (tractor with wagon and truck). Three types of agricultural biomass (loose, baled and briquetted) were considered for transport analysis. For all modes of transport, it was observed that unit cost of transport decreases with increase in distance. The transport cost was least for briquetted biomass as compared to loose and baled biomass. [Copyright &y& Elsevier]

Abstract: Agricultural biomass has immense potential for power production in an Indian state like Punjab. A judicious use of biomass energy could potentially play an important role in mitigating environmental impacts of non-renewable energy sources particularly global warming and acid rain. But the availability of agricultural biomass is spatially scattered. The spatial distribution of this resource and the associate costs of collection and transportation are major bottlenecks for the success of biomass energy conversion facilities. Biomass, being scattered and loose, has huge collection and transportation costs, which can be reduced by properly planning and locating the biomass collection centers for biomass-based power plants. Before planning the collection centers, it is necessary to evaluate the biomass, energy and collection cost of biomass in the field. In this paper, an attempt has been made to evaluate the spatial potential of biomass with geographical information system (GIS) and a mathematical model for collection of biomass in the field has been developed. The total amount of unused agricultural biomass is about 13.73Mtyear−1. The total power generation capacity from unused biomass is approximately 900MW. The collection cost in the field up to the carrier unit is US$3.90t−1. [Copyright &y& Elsevier]

Hydrophobic materials have the potential to replace the existing surface modification materials to combat the problem of cavitation erosion (CE), owing to their various capabilities like self-cleaning, anti-corrosion, anti-fogging, anti-icing, anti-fouling, and drag-reduction. Polytetrafluoroethylene (PTFE) as a hydrophobic material exhibits specific combination of properties such as low friction coefficient, chemically neutral, good impact strength and considerable thermal firmness, that allow PTFE to be used in a wide range of applications. Therefore, in this work, an effort has been made to explore the effect of thickness of hydrophobic PTFE coatings on CE of the hydro-machinery SS410 steel. Hydrophobic PTFE coatings with three variable thicknesses have been prepared on the hydro-machinery SS410 steel using sintering process. Using high-velocity submerged water jet cavitation erosion test rig, CE behaviour of PTFE coated and bare SS410 steel was evaluated under various combinations of operating parameters: namely jet velocity, stand-off distance (SOD), and impact angle. Contact angle was reported to be increased with the decrease in the thickness of PTFE layer, which may be due to the increased surface roughness of PTFE layer with decrease in thickness. CE resistance of PTFE coated material with a maximum thickness of 121 μm, was found to be highest for all the combinations of operating parameters, which may be attributed to its lowest fracture toughness and better cushioning effect. Further, it was observed that CE of the coated and SS410 steel was found to be maximum at the chosen maximum velocity, normal impact angle, and intermediate SOD. The signatures of pits with circular and elongated morphology were observed for normal and shallow impact angles, respectively. In case of lowest PTFE layer thickness, overlapped pits with relatively higher depth were observed, which might be responsible for higher CE of the same amongst all the PTFE coatings. • Cavitation erosion behaviour of Polytetrafluoroethylene (PTFE) coatings with different thickness. • Maximum cavitation erosion for intermediate stand-off distance, maximum jet velocity, and normal impact angle. • 121 μm thick PTFE coating exhibited a higher cavitation erosion resistance. • The signatures of pits for SS410 steel with circular and elongated morphology were observed. [ABSTRACT FROM AUTHOR]

Inconel 625 was cladded on EN-8 along with the blending of TiC powder (10%, 20%, and 30%) by utilizing the hybrid-mode Wire Arc Additive Manufacturing (WAAM) process, with an aim to increase the resistance against abrasive wear of tillage tools. Cladded specimens with maximum blending of 30% TiC showed superior wear resistance owing to higher microhardness and formation of elongated dendrites. However, the coefficient of friction enhanced with the addition of TiC particles. Specimen with oblique orientation showed better wear resistance owing to irregular and stronger grain orientation. Composite clads with TiC blend have been worn out with mixed mode of failure comprising of plastic deformation at Inconel 625 pool sites and no penetration in high TiC content regions. [ABSTRACT FROM AUTHOR]

α-Galactosidase, (E.C. 3.2.1.22) is an exoglycosidase that target galactooligosaccharides such as raffinose, melibiose, stachyose and branched polysaccharides like galactomannans and galacto-glucomannans by catalysing the hydrolysis of α-1,6 linked terminal galactose residues. The enzyme has been isolated and characterized from microbial, plant and animal sources. This ubiquitous enzyme possesses physiological significance and immense industrial potential. Optimization of the growth conditions and efficient purification strategies can lead to a significant increase in the enzyme production. To boost commercial productivity, cloning of novel α-galactosidase genes and their heterologous expression in suitable host has gained popularity. Enzyme immobilization leads to its greater reutilization, superior thermostability, pH tolerance and increased activity. The enzyme is well explored in food industry in the removal of raffinose family oligosaccharides (RFOs) in soymilk and sugar crystallization process. It also improves animal feed quality and biomass processing. Applications of the enzyme is in the area of biomedicine includes therapeutic advances in treatment of Fabry disease, blood group conversion and removal of α-gal type immunogenic epitopes in xenotransplantation. With considerable biotechnological applications, this enzyme has been vastly commercialized and holds greater future prospects. [ABSTRACT FROM AUTHOR]

Inconel 625 was cladded over tillage material EN8 with Wire Arc Additive Manufacturing (WAAM) - Cold metal Transfer (CMT) using varied input parameters. For examining the effectiveness of developed clads; dry sliding and slurry abrasion tests were conducted as per ASTM G65 standards under varying parameters. It has been perceived that cladded specimens have shown higher wear resistance than bare tillage material owing to their comparatively higher microhardness. The superlative results for maximum resistance to mass loss was found at 144 A current, 15.3 V voltage, 5 m/min wire feed speed, and 10 cm/min scanning speed. The bare and Inconel 625 cladded EN8 steel have showed ductile and mixed (ductile as well as brittle) mode of failure, respectively. [ABSTRACT FROM AUTHOR]

Leukemia is one of the deadliest types of cancer. Lack of effective treatment strategies has resulted in an extensive quest for new therapeutic molecules against it. This study explores the molecular mechanism of anticancer activity of P16, a semisynthetic analog of parthenin, against the human acute lymphoblastic leukemia MOLT-4 cells. P16 displayed antiproliferative activity in different cancer cell lines; however, MOLT-4 cells showed highest sensitivity for P16 with IC50 value of 0.6 μM. Further studies revealed that P16 induced cell death by apoptosis. It caused mitochondrial stress, which was mediated by the translocation of Bax from cytosol to mitochondria and release of cytochrome c into the cytosol and consequent activation of caspase-9. However, P16 was also able to activate caspase-8, thus involving both extrinsic and intrinsic pathways of apoptosis. Further, activation of caspase-3 led to cleavage of its target proteins PARP-1 and ICAD, which resulted in apoptotic DNA damage. P16 induced apoptosis was accompanied by the down-regulation of important leukemic cell survival proteins like pAKT (S473), pAKT (T308), pP70S6K, pCRAF, and pERK1/2. However, inhibition of caspases by Z-VAD-FMK reversed the down-regulatory effect of P16 on pAKT (S473) and pP70S6K, as evident by the cell viability assay and flow cytometric analysis but this inhibition did not completely reverse the antiproliferative effect of P16, thereby indicating the role of additional factors apart from caspases in P16 induced apoptosis in MOLT-4 cells. Owing to its antiproliferative potential against leukemia cells, P16 can further be explored as an effective therapeutics against leukemia. [ABSTRACT FROM AUTHOR]