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Chitinase-producing fungi have now engrossed attention as one of the potential agents for the control of insect pests. Entomopathogenic fungi are used in different regions of the world to control economically important insects. However, the role of fungal chitinases are not well studied in their infection mechanism to insects. In this study, Chitinase of entomopathogenic fungi Trichoderma longibrachiatum was evaluated to control Aphis gossypii. For this purpose, fungal chitinase (Chit1) gene from the genomic DNA of T. longibrachiatum were isolated, amplified and characterised. Genomic analysis of the amplified Chit1 showed that this gene has homology to family 18 of glycosyl hydrolyses. Further, Chit1 was expressed in the cotton plant for transient expression through the Geminivirus-mediated gene silencing vector derived from Cotton Leaf Crumple Virus (CLCrV). Transformed cotton plants showed greater chitinase activity than control, and they were resistant against nymphs and adults of A. gossypii. About 38.75% and 21.67% mortality of both nymphs and adults, respectively, were observed by using Chit1 of T. longibrachiatum. It is concluded that T. longibrachiatum showed promising results in controlling aphids by producing fungal chitinase in cotton plants and could be used as an effective method in the future. [ABSTRACT FROM AUTHOR]

Among all other leading challenges of this century, climate change affects people's livelihoods, particularly those residing in rural areas. This study is the first attempt to assess the Long-run (LR) and Short-run (SR) impacts of climatic factors, namely CO2 emissions, temperature, and precipitation on maize production in Nepal from 1983 to 2016, with the incorporation of cultivated area, fertilizers use, and credit supply as important input factors of maize production. To analyze the time-series dataset, we applied the Autoregressive distributed lag (ARDL), Vector error correction model (VECM), Impulse response function (IRF), and Variance decomposition (VD) methodologies. The results reveal that CO2 emissions and temperature decreased maize production in the short- and long-run while precipitation improved maize production in both cases. Also, cultivated area and fertilizers use significantly contributed to maize production in both periods. The results of the VECM causality indicate that rainfall and cultivated area have two-way causal associations with maize production. The CO2 emissions and credit represent unidirectional causality with maize production in the short-run. Besides, all variables share a significant long-run connection. Finally, the IRF and VD outcomes suggested that the effects of climatic and non-climatic factors are consistent on maize production. The policies recommend that better environmental quality is crucial for sustainable maize production in Nepal. [ABSTRACT FROM AUTHOR]

Pneumonia remains a leading cause of morbidity and mortality in developing countries. Comprehensive surveillance data are needed to review the prevention and control strategies. We conducted active surveillance of acute lower respiratory infections among children aged <2 years hospitalized at two hospitals of Islamabad, Pakistan. Viral etiology was determined using real-time PCR on respiratory specimens collected during March 2011-April 2012. The overall mean age was 7.83 ± 5.25 months while no statistical difference between age or sex distribution of patients with positive and negative viral etiology ( p > 0.05). The average weight of the study group was 6.1 ± 2.25 kg. ≥1 viral pathogens were detected in 75% cases. Major respiratory viruses included RSV-A: 44%, RSV-B: 23%, Influenza-A: 24.5%, Influenza-B: 7%, Adenovirus: 8.4% and HmPV: 5.2%. A single, dual or multiple viral pathogens were detected in 43%, 27% and 5.2% patients respectively. Common symptoms were cough (95%), apnoea (84%), fever (78%), wheeze (64.5%), nasal congestion (55%) and rhinorrhea (48%). Among the RSV positive cases, 2-6 months age group had highest detection rate for RSV-A (30%, n = 21/69) and RSV-B (20%, n = 14/69) while patients infected with Influenza-A were in 2.1-6 months age group (61%, 23/38). Statistically significant difference was observed between RSV-positive and negative cases for nutrition status ( p = 0.001), cigarette/wood smoke exposure ( p = 0.001) and concomitant clinical findings. Most patients had successful outcome on combination therapy with bronchodilators, inhaled steroids and antibiotics. Our findings underscore high burden of ALRI in Pakistan. Interventions targeting viral pathogens coupled with improved diagnostic approaches are critical for better prevention and control. [ABSTRACT FROM AUTHOR]

Oxidation of cellulosic materials is required in many fields such as textile processing, natural fiber composites, medical utilization, and so on. The present study was designed to explore the possibility of ozone treatment as a greener oxidation process for jute fibers. Ozone gas was used for the treatment of waste jute fibers for different time periods in a humid atmosphere. Several characterization techniques, namely physical appearance, fiber mechanical properties, the copper number, Fourier transform infrared spectroscopy, wide-angle X-ray diffraction, scanning electron microscopy, moisture regain percentage and lightness values ( L), were used to assess the effect of treatment on jute fibers. Results showed that fiber tensile properties weaken gradually as a function of treatment time, and surface functional groups alter accordingly. Changes in crystallinity after ozone treatment were also observed. Physically the fiber bundles were split into brittle single fibers, and the L value increased from a brownish shade to lighter color. [ABSTRACT FROM AUTHOR]

The current study presents rational cubic trigonometric Bézier curve with two shape parameters, which is a novel technique for drawing free form curves. The proposed curve retains most of the geometric properties of conventional rational cubic Bézier but is flexible due to the presence of shape parameters. The shape of the curve can be adjusted locally by altering the values of shape parameters as well as the weights. Using the given end point curvatures, conditions on shape parameters and weights have been driven so that the curve always lies in the convex hull of its control point. Later, this curve is used to generate piecewise rational trigonometric curves stitched together using parametric and geometric Hermite continuity conditions which can facilitate a designer to generate a smooth composition of curves in a situation where single curve does not work. The piecewise curves thus constructed are used to draw the layout of certain English and Arabic alphabets as an application in font designing. [ABSTRACT FROM AUTHOR]