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Accurate and reliable long term meteorological data is very difficult to be obtained in developing countries especially in hard and mountainous regions. This paper focuses to select the most suitable and reliable gridded datasets for the two most important meteorological parameters i.e., precipitation and temperature in a sparsely gauged transboundary Kabul River Basin (KRB) between Pakistan and Afghanistan. Novelty of this study is that gridded datasets were evaluated for precipitation and temperature based on monthly, seasonal and annual timescales against the available observed stations data on both sides of the KRB. Based on the literature studies, the five most frequently used datasets namely; National Centers for Environmental Prediction, Climate Forecast System Reanalysis (NCEP-CFSR), Asian Precipitation Highly Resolved Observational Data Integration towards Evaluation (APHRODITE v1101), Global Precipitation Climatology Centre (GPCC), Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks-Climate Data Record (PERSIANN-CDR) and Climate Research Unit (CRU TS v4.02) with different spatial and temporal resolutions were selected and evaluated. Analyses were done using the four most widely used statistical indices i.e., Modified Index of Agreement (d), Pearson's Correlation m Coefficient (r), Root Mean Square Error (RMSE), and Relative Bias (RB%). Results revealed that based on the statistical indices scores; APHRODITE (v1101) showed the best results followed by GPCC for precipitation while for temperature, CRU (TS v4.02) was found better compared to other datasets in the study basin. These findings can be used with confidence by the researchers for the future studies whose outcomes could be utilized by the water resource managers, planners and agriculturists. [ABSTRACT FROM AUTHOR]

Horse purslane (Trianthema portulacastrum L.) is one of the major and problematic weed of summer season in Pakistan that is responsible for yield reduction. A research trial was carried out at Muhammad Nawaz Sharif University of Agriculture Multan during Kharif, 2018 to compare the competitive effect of horse purslane and other weeds for different intervals regarding growth and yield of cotton. Horse purslane is considered the noxious weed of cotton crop. Cotton is an important, fiber and cash crop of Pakistan. Its raw material and other products are exported to other countries. The study was conducted using the randomized complete block design with three replications. The treatments were; horse purslane free crop for whole season, horse purslane free crop for 30 days after sowing (DAS), horse purslane free crop for 60 DAS, horse purslane and other weeds free crop for whole season, horse purslane and other weeds free crop for 30 DAS, horse purslane and other weeds free crop for 60 DAS, weedy check (horse purslane only), weedy check (all weeds except the horse purslane) and weedy check (all weeds including horse purslane). Weed density, weed dry biomass, crop growth and yield related parameters were recorded following standard procedures. All recorded data were analyzed with the help of Fisher's Analysis of Variance. The means of different treatments were separated by using Tukey's HSD test at 5% probability level. Horse purslane reduced the height of cotton plants by 26.51%, crop growth rate in terms of biomass by 28.44%, total dry matter 28.46% and seed cotton yield by 45% as compared to weed free treatment for whole season. The increase in yield in horse purslane free crop for whole season (23.45%), horse purslane free crop for 30 DAS (14.27%), horse purslane free crop for 60 DAS (18.07%), horse purslane and other weeds free crop for whole season (124.03%), horse purslane and other weeds free crop for 30 DAS (63.48%) and horse purslane and other weeds free crop for 60 DAS (103.73%) was recorded as compared to all weeds (weedy check). Treatment having horse purslane and other weeds free crop for whole season gave high seed cotton yield than other treatments. Whereas, the highest benefit cost ratio (1.70) was observed for plot that was kept free from horse purslane and other weeds till 60 DAS. [ABSTRACT FROM AUTHOR]

Majority of the water supply schemes in the Northern Khyber Pakhtunkhwa have natural springs as source of water supply and utilizing it without any physical or chemical treatments except for primary sedimentation. The physiochemical characteristics of these rural sources of water supply are very little understood. This study primarily investigates the water quality of randomly selected springs located in Dir, Malakand, and Swat Districts to check the suitability of spring water for drinking purposes as per National Standards of Drinking Water Quality (NSDWQ) and according to World Health Organization (WHO) guidelines. Water samples from different springs were collected at different time interval and analyzed for physiochemical parameters. The concentrations of the parameters were compared with the NSDWQ and WHO guidelines. Samples were analyzed for color, electrical conductivity (EC), odor, suspended solids (SS), total dissolved solids (TDS), taste, temperature (T), turbidity, pH, alkalinity, calcium (Ca+2), carbonates. [ABSTRACT FROM AUTHOR]

Open circuit voltage (VOC) of organic bulk heterojunction solar cell is extended by the addition of a 20 wt % of F8TBT, an ambipolar polymer in the active layer matrixes (P3HT:PCBM) and then spin casted (1000 rpm/30 s) in the optimized devices on the PEDOT:PSS layer of the ITO glass. A substantial increase in the open circuit voltage from approximately 0.61–0.88 V (44.26%) has been observed with slight increase in efficiency up to 1.91% in the fabricated devices. However, further increment of F8TBT content to 40 wt % reduces the photovoltaic efficiency and affects the JSC values remarkably, possibly due the excess amount of resistance developed. The enhancement of VOC is attributed to the ambipolar nature of F8TBT polymer which facilitates the generated electron and hole transfer at the respective electrodes, enhanced π–π* conjugation in polymer matrix, a superior nanoscale separation, and better molecular conformation at the film interface, thus giving an ample opportunities to explore the impact of blending of materials rather than depositing a thin buffer layer by expensive vapor phase technologies. The details of electrical and microstructure characterization of the film were analyzed by AFM, SEM, UV–Vis, J–V characteristics, and EQE techniques. [ABSTRACT FROM AUTHOR]