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Laccases are oxidoreductases enzymes that belong to the sub class copper oxidases. They are mainly produced by white rot fungi which are involved in lignin metabolism. The objective of this research was the effective utilization of agro wastes for the economical production of laccase from, fungi Pleurotusflorida. Submerged fermentation was employed for the production of enzyme and agro wastes namely rice husk, wheat bran and sugarcane bagasse used as substrates. The activity of enzyme was analyzed spectrophotometrically at 420nm, using ABTS (2,2'-Azino-bis(3- ethylbenzthiazoline-6-sulfonic acid) as a substrate. The maximum production was obtained with sugarcane bagasse 9.9 IU/ml at day 9. The optimum temperature and pH were found to be 30°C and 7. The best nitrogen source optimized was ammonium sulphate which enhanced the production up to 11.57 IU/ml. The large scale batch (1litre) with already optimized conditions produced 13460 IU/L of enzyme. Purification was performed and molecular weight was determined at 90kDa through SDSPAGE. Characterization of enzyme was done in terms of pH, temperature and effect of inducers and inhibitors. [ABSTRACT FROM AUTHOR]

Jatropha curcas, has a great potential to replace soya bean. The main problems are the anti-nutritional factors, which hinder its use as an alternative protein source in the animal feed. The present study was focused on the detoxification of J. curcas seed. Detoxification was carried out using a mixture of aqueous methanol (9:1) and NaOH (0.15%) at 60 C for 30 min. subsequent washing with methanol and then oven dried. Results showed significant detoxification (P>0.05) of J. curcas. The impact of feeding detoxified J. curcas to rats was studied. The detoxified J. curcas seed meal (DJM) at the rate of 25, 50, 75 and 100% was offered to albino rats (n=36) of almost equal weights (45±0.76gm). On blood and serum analysis the white blood cells (WBC) (7.23±0.29, 10.56±0.16, 8.29±0.30, 5.94±0.17, 5.6±0.177 and (7.07±0.27), red blood cells (RBC) count (6.73±0.109, 7.61±0.18, 7.00±0.056, 6.68±0.96, 6.28±0 and 5.83±0.18), hemoglobin (11.94±0.11, 12.29±0.19, 12.66±0.27, 11.78±0.14, 10.97±0.177 and 10.97±0.177), total protein (5.33±0.09, 5.17±0.86, 4.6±0.096, 4.41±0.109, 4.1±.096 and 3.82±0.13), uric acid (32.25±0.82, 34.83±0.32, 54.83±0.84, 61.75±0.68, 62.36±0.7135 and 26±0.34), creatinine (0.841 ±0.017, 801±.018, 0.841±0.027, 0.833±0.032, 0.801± 0.14 and 1.44±0.049) and LFT (liver function test) including alkaline transaminase (29.2± 0.42, 24.13±0.37, 21.133±0.48 , 32.006±1.39, 75.93± 2.16 and 24.75±0.377), Aspartate transaminase (3.20±1.01 2.08±1.03, 1.25±1.4, 1.33±0.71, 1.82±0.72 and 1.81±1.47) and Alkaline phosphatase (4.96±1.09, 4.14±0.71, 4.79±1.47, 5.30 ±1.5, 5.6±2.3 and 2.08±2.3) didn’t differ signicantly among the experimental groups. A significant increase (P>0.05) in red blood cells and hemoglobin level was observed in 25 (7.61±0.18) and 50% (7.0±0.056) DJM fed groups as compared to control group (6.73±0.0.109). There was an increase in the value of PER (Protein efficiency ratio), TD (True digestibility), NPU (±Net protein utilization) and BV (Biological value) of 25% (0.32±.009, 77.66±.21, 65.33±.17 and 83.42±0.16) and 50% DJM fed rats (0.42±.007, 88.08±.26, 75.5±0.18, 85.10±0.073) as compared to control group (0.36±.004, 90.5±0.22, 75.25±0.17, 83.0±0.14). Present study indicated that 50% DJM protein fed group has the same performance as the control group and better than other experimental groups, that showed a better efficiency of detoxified J. curcas meal as an alternative livestock feed. [ABSTRACT FROM AUTHOR]

Composites are usually brittle materials and have low impact properties. Structural dimensions, stacking sequence, ply materials, ply thicknesses and ply angles are standard variables that influence composite's performance against impact loads. Stacking sequence in hybrid laminates affects the failure and impact resistance. Failure mechanisms at the low‐velocity impact of a rigid object in hybrid laminates are complex, and the subsurface damage in a composite laminate cannot be detected directly. However, various simulation platforms make it easy to see the impact damage between the plies of laminate. This paper numerically investigated the effect of stack sequence and hybridization of two fiber types against low‐velocity impact. The current study adopted four‐layer composite laminates of carbon and glass fiber layers with a stacking plan [C/C/C/C], [C/G/C/G] and [G/C/G/C], having lay‐up angles as [0°/45°/−45°/90°]. Keeping the impactor mass and the incident velocity constant, the laminates were subjected to low‐velocity impact. The damage contours for a failure mode were recorded and compared at the ply level. The numerical study resulted in impact imitations showing comparisons of the damage contours using Hashin failure criteria. Hybrid laminates display better performance in absorbing impact energies; however, hybrid laminates experienced more subsurface damage due to more impact energy absorption. [ABSTRACT FROM AUTHOR]

With numerous reinforcements, aluminum and its alloys are finding growing applications in every sector of industry. Titanium carbide (TiC) is regarded as an outstanding reinforcing material as compared to widely used carbide particles because of its excellent physical and mechanical characteristics, as well as its especially good interfacial bonding (wetting) capacity with aluminum. In the present research work, the effect of the mixing time of the matrix and reinforcement powders has been investigated on the crystallite size and lattice strain of the AA7075–5 wt.% TiC composites. The mechanical properties of the developed composites were also investigated in terms of microhardness values. X‐ray diffraction and scanning electron microscopy (SEM), transmission electron microscopy (TEM), particles size distribution analysis and x‐ray energy dispersive spectroscopy (EDS) of the synthesized powder samples were done to see the effect of mixing time on their microstructures. The increase in mixing time led to a homogeneous distribution of 5 wt.% of TiC particles, a decrease in particles clustering. The considerable grain refining was confirmed, which reflected a reduction in particle size originating from a prolonged mixing time. The significant improvement in the crystallite size and microhardness of the produced composites were achieved with increasing mixing time. [ABSTRACT FROM AUTHOR]

Thermal oils are widely used as working fluids in the medium temperature heat transfer applications including concentrating solar thermal collectors. However, the weak thermal characteristics of these oils are major drawbacks in their successful application in the medium‐high temperature solar collectors. Fortunately, the emergence of nanotechnology has provided the opportunity to alter thermo‐physical properties of base fluids by adding small amount of sub‐micron size solid particles possessing better properties. This paper presents an experimental investigation of thermophysical properties of an oil‐based nanofluid to be used in the medium temperature solar collector for enhanced thermal energy transport. The colloidal suspensions were prepared by dispersing different weight fractions (0.25 wt.%, 0.5 wt.%, 0.75 wt.% and 1.0 wt.%) of Titania nanoparticles in Therminol‐55 oil using two‐step method. Shear mixing and high energy ultrasonication was employed to achieve uniform mixing and de‐agglomeration of the nanoparticles in order to enhance the stability of the colloidal suspensions. Thermophysical properties of the nanofluids were determined as a function of nanoparticles concentrations in the temperature range of 25 °C–130 °C. The experimental results demonstrated substantial improvement in thermal conductivity of the nano‐oils with an increase in nanoparticles loading which further enhanced at higher temperatures. Dynamic viscosity and effective density displayed a decreasing trend against rising temperature which indicate the effectiveness of these nanofluids for medium temperature heat supply. Nano‐oils with superior thermal properties can improve the performance of medium temperature solar thermal collectors. [ABSTRACT FROM AUTHOR]

Filamentous fungi is the basic source of hydrolytic enzymes and widely used for industrial applications. Aspergillus fumigatus have been widely used for the production of hydrolytic enzymes. The present study was undertaken to demonstrate the production of glucoamylase from Aspergillus fumigatus using wheat bran as substrate. A. fumigatus was isolated from organic waste samples from river Ravi, Lahore, Punjab, Pakistan and the conditions were optimized for its growth. Various carbon and nitrogen sources were utilized for the supplementation of growth medium in order to produce higher level of glucoamylase. The produced enzyme was partially purified by fractional ammonium sulphate precipitation followed by dialysis for the removal of salt. The dialyzed sample was further purified by ion exchange and gel filtration chromatography. The purified protein was utilized for the kinetic studies. Purification studies resulted in 12 fold purification with 45% yield of the glucoamylase. SDS-PAGE analysis of the purified enzyme revealed an approximate size of 60 kDa. Under optimal conditions, we were able to produce 28 U/mL of glucoamylase. Highest enzyme activity was observed when A. fumigatus was grown on 3% wheat bran in the presence of 0.7% Tween-80 at 40°C for 72 hours at pH 5.0. Kinetic studies demonstrated the Km and Vmax values 9.1 mg/mL and 40 µM min-1 mg-1 respectively when starch was utilized as substrate. Present study revealed a new source of glucoamylase, which have ability to utilize a variety of agriculture products as carbon sources that can be useful for enzyme industry. This study discovered a new strain, which is a unique machine that can act as an attractive alternative source for the production of industrial enzymes for starch hydrolysis. To our knowledge this is the highest glucoamylase activity from Aspergillus fumigatus sp. so far. [ABSTRACT FROM AUTHOR]

Thermal oils are widely used as heat transfer fluids in medium temperature applications. Addition of small amounts of nanoparticles in such fluids can significantly improve their thermophysical properties. This paper presents experimental investigation of an oil‐based nanofluids prepared by dispersing different concentrations (0.25 wt%–1.0 wt%) of copper oxide nanoparticles in Therminol‐55 oil using two‐step method. Shear mixing and ultrasonication were used for uniform distribution and de‐agglomeration of nanoparticles to enhance the stability of the suspensions. The effect of nanoparticles concentrations on thermophysical properties of the nanofluids was analysed by measuring thermal conductivity, dynamic viscosity, effective density and specific heat capacity at different temperatures (25 °C–130 °C). Thermal conductivity exhibited increasing trend with rising temperature and increase in nanoparticles loading. A significant decrease in dynamic viscosity and effective density against increasing temperature makes it suitable for medium temperature applications. Nano‐oils with improved thermal properties are expected to increase the efficiency of concentrating solar thermal collectors. [ABSTRACT FROM AUTHOR]

The immune systems of species are basically dynamic for evolution and survival, and the animal selection patterns in innate immune loci are of prodigious importance in molecular evolutionary research. Interferon alpha (IFN-α) plays a fundamental role in innate immune response with biological and antiviral activity. In the current study, the IFN-α gene was genetically and phylogenetically characterized in thirty Beetal goats by direct sequencing. Genomic DNA was isolated and sequencing analysis of IFN-α gene revealed two missense substitutions (A83G: Lys28Arg, A127G: Thr43Ala) and one synonymous substitution (A144G). Phylogenetic analysis and genetic distance showed the specieswise clustering and higher genetic distance with other goats. This information in Pakistani indigenous goats may provide useful insights into the design of molecular selection strategies for genetic improvement of animal and further biological studies in other goat breeds may provide evolutionary way to acquire better disease resistant animals. [ABSTRACT FROM AUTHOR]