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101.
Contamination of freshwater bodies and consequently freshwater fish with toxic heavy metals is a serious environmental issue. The trophic transfer of potentially toxic heavy metals in the human food chains, especially in fish has important implications for human health. The present research study was designed to assess the concentrations of the heavy metals Cr, Ni, Cd, and Pb in the water, sediments, and different freshwater fish species of River Kabul, Pakistan. The heavy metals were quantified in the samples with Atomic Absorption Spectrophotometer. Heavy metal contamination in fish muscles was characterized in terms of metal pollution index and biota-sediments accumulation factor, while human health risk was assessed through calculation of estimated weekly intake. The average concentrations of Cr, Ni, Cd, and Pb in muscle samples of the analyzed fish species at different sampling sites of the river ranged from 12.3 to 33.0, 33.2 to 109.2, 0.98 to 1.5, and 13.9 to 29.6 mg kg?1 wet weight, respectively. Based on the current study data, consumption of the analyzed freshwater fish species from River Kabul was generally safe in terms of potential risk from Cd and Pb but the observed Ni accumulation may pose a potential health risk to regular/excessive fish consumers.  相似文献   
102.
Two new species of Hedysarum, H. alii Haidar Ali & Qaiser sp. nov. and H. shahjinalense Haidar Ali & Qaiser sp. nov. are described from Chitral in Pakistan. As far as known, both new species are endemic to Chitral and are categorized as ‘Critically Endangered’ (CR). In addition, three other species of Hedysarum are recorded from Pakistan for the first time, viz. H. volkii Rech. f., H. brahuicum Boiss. and H. sericeum M. Bieb. These are also ‘Critically Endangered’ (CR) at a national level. A key to all 12 species of Hedysarum occurring in Pakistan is provided.  相似文献   
103.
棉花是巴基斯坦唯一批准种植和使用的转基因作物。监管的不明确阻碍了生命科学公司为其他转基因作物寻求获批,但国家生物安全委员会仍在制定转基因食品、饲料和加工品的进口准则。2020年,巴基斯坦进口了大约220万t大豆,其中美国占据了近50%的市场份额。  相似文献   
104.
We present new material of the selenodont anthracothere Hemimeryx blanfordi from the Oligocene deposits of the Bugti Hills (Balochistan, Pakistan), collected between 1999 and 2002. This is the first undisputed Oligocene occurrence of the species, previously known from the early Miocene of Pakistan. Investigation of the molar enamel microstructure reveals a surprising mono-zonal Schmelzmuster, already detected in some middle to Late miocene selenedont anthracotheres. We include this observation combined with a morphological revision of H. blanfordi and a cladistic assessment of the dental evidence, to propose a new phylogenetic hypothesis regarding Hemimeryx and its close relatives. We confirm the clade including advanced bothriodontines, which we erect to a tribe rank and name Merycopotamini. The South Asian origin of Merycopotamini is consistent with hypothesized subsequent dispersal events of Merycopotamini from Asia to Africa.  相似文献   
105.
The current analyses of vegetation were aimed to study the different effects of environmental variables and plant species and communities interaction to these variables, identified threats to local vegetation and suggestion for remedial measures in the Mount Eelum, Swat, Pakistan. For assessment of environmental variability quantitative ecological techniques were used through quadrats having sizes of 2 × 2, 5 × 5 and 10 × 10 m2 for herbs, shrubs and trees respectively. Result of the present study revealed 124 plant species in the study area. Canonical Correspondence Analysis (CCA) was used to analyze the ecological gradient of vegetation. The environmental data and species abundance were used in CANOCO software version 4.5. The presence absence data of plant species were elaborated with Cluster and Two Way Cluster Analysis techniques using PC-ORD version 5 to show different species composition that resulted in five plant communities. Findings indicate that elevation, aspect and soil texture are the strongest variables that have significant effect on species composition and distribution of various communities shown with P value 0.0500. It is recommended to protect and use sensibly whole of the Flora normally and rare species particularly in the region.  相似文献   
106.
Taxonomic identification and classifications of insect pest genera Chrysodeixis and Ctenoplusia of the subfamily Plusiinae is very compulsory due to their phytophagous nature and potential to damage the cash as well as cereal crops. Taxonomy plays a key role in proper not only in identification and classification of the pest but also in designing a successful managing strategy. In current study, specimens of Chrysodeixis and Ctenoplusia genera were collected from different geographical areas of south Punjab, Pakistan and their diagnostic features were examined following taxanomic keys. The data of temperature, relative humidity and rainfall were also recorded during the study period. Genitalia was extracted by dissecting of the abdomen and inspected under Stereo microscope. The results revealed two new species, Chryodeixis maxus and Ctenoplusia oleraceaus, from south Punjab region in addition to previously reported species: Chrysodeixis furihatai. Suitable management of the voracious insect pest at appropriate time may help in sustaining the agriculture in Pakistan.  相似文献   
107.
COVID-19 has swept globally and Pakistan is no exception. To investigate the initial introductions and transmissions of the SARS-CoV-2 in Pakistan, we performed the largest genomic epidemiology study of COVID-19 in Pakistan and generated 150 complete SARS-CoV-2 genome sequences from samples collected from March 16 to June 1, 2020. We identified a total of 347 mutated positions, 31 of which were over-represented in Pakistan. Meanwhile, we found over 1000 intra-host single-nucleotide variants (iSNVs). Several of them occurred concurrently, indicating possible interactions among them or coevolution. Some of the high-frequency iSNVs in Pakistan were not observed in the global population, suggesting strong purifying selections. The genomic epidemiology revealed five distinctive spreading clusters. The largest cluster consisted of 74 viruses which were derived from different geographic locations of Pakistan and formed a deep hierarchical structure, indicating an extensive and persistent nation-wide transmission of the virus that was probably attributed to a signature mutation (G8371T in ORF1ab) of this cluster. Furthermore, 28 putative international introductions were identified, several of which are consistent with the epidemiological investigations. In all, this study has inferred the possible pathways of introductions and transmissions of SARS-CoV-2 in Pakistan, which could aid ongoing and future viral surveillance and COVID-19 control.  相似文献   
108.
The mean fat cell diameter was determined from measurements of abdominal adipose cells, obtained during inguinal hernia repair, of 126 white and 95 black males ranging in age from 1 through 48 months of age. The mean diameters of black and white subjects did not differ significantly, suggesting that differences in fatness among adults of these two ethnic groups have their origin beyond the age range of this study. The mean fat cell diameter increased through the 6-8 month age group, decreased until the end of the first year, and then levelled off through 48 months of age. Comparison of this curve with those for the triceps, subscapular, abdominal, and suprailiac skinfolds of the same subjects showed generally parallel courses except for the triceps, which continued to increase in size after the means of fat cell diameters and the other skinfolds had levelled off. Our data indicate that changes in body fatness on the trunk at least in the first 4 years of life may be accounted for by changes in fat cell size.  相似文献   
109.
Illegal trade is a major threat to the biodiversity and the efforts initiated for the conservation of wildlife. The shortcomings of the traditional taxonomic identification methods have been coped by a revolutionary and emerging technique, the “DNA (Deoxyribonucleic Acid) barcoding”. Here we report a case of trader who was allegedly making footwear for a famous international celebrity from wild animal cutis. The samples confiscated during a raid on a footwear manufacturing industry by KP Wildlife department in August, 2016, were received by Bioresource Research Centre (BRC) for molecular identification on 1st September, 2016. The study costed about USD 88 from processing to the identification of the samples. The samples identified via DNA mini-barcoding by targeting cytochrome oxidase I (COI) gene belong to Gazella bennettii and Bos taurus. Such studies are helpful for credible investigations that only lead to effective prosecution and control of illegal wildlife trade ultimately helping in conservation of wild animals.  相似文献   
110.
This study explores the validation of the Environmental Kuznets Curve (EKC) hypothesis for Pakistan using time series data from 1980–2013 with deforestation as an indicator (dependent variable) for environmental degradation, and four independent variables (economic growth, energy consumption, trade openness, and population) were also examined. The Autoregressive Distributed Lag (ARDL) bounds testing approach to cointegration and the VECM–Granger causality test were applied. The results confirmed the existence of cointegration among the variables both in long- and short-run paths. However, the diminishing negative impact of economic growth on deforestation in the long-run confirms the EKC hypothesis for deforestation in Pakistan. Moreover, economic growth and energy consumption Granger cause deforestation. A bidirectional causal effect is detected between economic growth and energy consumption, however, in the long-run, economic growth and trade openness Granger cause energy consumption. This study was designed with several significant tests to ensure the reliability of results for policy use and to contribute to future studies on the environment-growth-energy nexus.  相似文献   
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