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121.
Muhammad Shuaib Kashif Ali Sajjad Ahmed Firasat Hussain Muhammad Ilyas Nazim Hassan Ikramullah Khan Fida Hussain 《农业工程》2018,38(6):394-400
In the World urbanization is a serious problem especially in developing countries which creates serious environmental problems like climatic and ecological changes in the ecosystem. The present paper aims to explain urbanization that causes loss of agriculture lands, biodiversity, soil erosions and grazing in District Dir. Urbanization decreased species richness such as Salix alba and Populus alba in the last few years in the local area. Soil of local area was divided into three different zones and was tested for soil texture and mineral percentage. Zone I soil showed sandy loamy texture with a pH of 8.3, Nitrogen 0.012%, Phosphorus 5.0% and organic matter was 0.74 (ppm). Zone II soil was loamy sand in texture with pH 8.1, Nitrogen 0.011%, Phosphorus 6.2%, and organic matter was 0.24 (ppm) while Zone III soil texture was silty clay loam with a pH of 8.1, Nitrogen 0.032%, Phosphorus 11.3%, and organic matter was 0.60 (ppm). The current work concludes that urbanizations affect natural biodiversity and agriculture lands, and that soil erosion and watering-points trampled by livestock is one of the significant problems in district Dir, and that the main degrading factor is the overexploitation of vegetation for fuel-wood and livestock grazing. 相似文献
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Lubna Bilal Sajjad Asaf Muhammad Hamayun Humaira Gul Amjad Iqbal Ihsan Ullah In-Jung Lee Anwar Hussain 《Symbiosis (Philadelphia, Pa.)》2018,76(2):117-127
Endophytes can serve as plant growth promoters as they secret a vast array of phytohormones to support host plants. Keeping the growth promoting activity of the endophytes in view, two endophytic fungi, Asprgillus fumigatus TS1 and Fusarium proliferatum BRL1 have been isolated from the roots of Oxalis corniculata. The isolates have been screened initially for growth promoting activities, including siderophores activity, phosphate solubilization, and secreation of indole acetic acid and gibberellins. Further, the isolates have assayed for the ability to promote the growth of mutant rice Waito-C. The plants associated with TS1 and BRL1 have shown higher chlorophyll content, root-shoot length, and biomass production. The growth promoting activity of the endophytes can be attributed to the various types of GAs and IAA that have been observed in the culture filtrates of the endophytes by the Gas chromatography/mass spectrometry (GC/MS). The GC/MS analysis revealed the presence of different gibberellins concentrations (ng/ml) in TS1 and BRL1 culture filtrate, i.e. GA1 (0.091?±?0.009, 0.392?±?0.007), GA3 (0.324?±?0.077, 0.089?±?0.0007) and GA7 (0.023?±?0.002, 0.492?±?0.005), respectively. Besides, a significant up regulation of plant endogenous GA1 (12.443?±?0.454 and 15.434?±?0.245) has been obsereved in TS1 and BRL1 associated plants compared to the control. Moreover, semi quantitative RT-PCR has confirmed the presence/invovment of GA pathways genes (P50–1, P450–3, P450–4, ggs2, and des). The results conclude that the endophytes isolated in this study can ably synthesize bioactive compounds, which play an important role in plant growth promotion. 相似文献
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125.
Wasim Sajjad Muhammad Rafiq Ma Xiangxian Suliman Khan Abdul Haq 《Geomicrobiology journal》2013,30(8):715-726
AbstractThis study aimed to investigate the ability of pure and consortia of indigenous iron-oxidizing bacteria to enhance the dissolution of trace metals from Cu and Zn-bearing ore. Three bacterial strains Acidithiobacillus ferrooxidans strain WG101, Leptospirillum ferriphilum strain WG102, Leptospirillum ferrooxidans strain WG103 isolated from Baiyin copper mine, China were used in this study. The biotechnological potential of these indigenous isolates was evaluated both in pure and in consortia to extract cobalt, chromium, and lead from the copper and zinc bearing ore. The sulfur and iron-oxidizing bacterial isolate Acidithiobacillus ferrooxidans strain WG101 exhibited efficient dissolution compared to sole iron-oxidizing Leptospirillum ferriphilum strain WG102, and Leptospirillum ferrooxidans strain WG103. Initial medium pH, pulp density, and temperature were studied as influential parameters in bioleaching carried out by bacterial consortia. The achieved optimum conditions were; initial pH of 1.5, 10% of pulp density, and temperature 30?°C with 68.7?±?3.9% cobalt, 56.6?±?3.9% chromium, and 36?±?3.7% lead recovery. Analytical study of oxidation-reduction potential and pH fluctuation were observed during this whole process that shows the metal dissolution efficiency of bacterial consortia. Alterations in spectral bands of processed residues were reported through FTIR analysis compared with control ore sample. Mössbauer spectroscopy analysis showed the influence of bacterial consortia on iron speciation in bioleached samples. The findings confirm that the indigenous acidophilic iron-oxidizing bacterial strains are highly effective in the dissolution of trace elements present in ore samples. This study not only supports the notion that indigenous bacterial strains are highly effectual in metal dissolution but provides the basic vital conditions to upscale the bioleaching technique for metals dissolution. 相似文献
126.
Hakim Sughra Mirza Babur S. Zaheer Ahmad Mclean Joan E. Imran Asma Yasmin Sumera Sajjad Mirza M. 《Applied microbiology and biotechnology》2018,102(1):485-497
Applied Microbiology and Biotechnology - In the present study, the relative distribution of endophytic rhizobia in field-collected root nodules of the promiscuous host mung bean was investigated by... 相似文献
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128.
Oliver Baylis Paul Rooney Francisco Figueiredo Majlinda Lako Sajjad Ahmad 《Journal of cellular physiology》2013,228(5):1025-1030
Limbal stem cell deficiency is a blinding disease which affects the cornea at the front of the eye. The definitive cure involves replacing the corneal epithelial (limbal) stem cells, for example by transplanting cultured limbal epithelial cells. One method of performing cultures is to grow a sheet of epithelial cells from a limbal explant on human amniotic membrane. The growth of limbal tissue can be variable. The aim of this study is to investigate how different donor and culture factors influence the ex vivo growth of cadaveric limbal explants. Limbal explant cultures were established from 10 different cadaveric organ cultured corneo‐scleral discs. The growth rate and the time taken for growth to be established were determined. Statistical analysis was performed to assess correlation between these factors and donor variables including donor age, sex, time from donor death to enucleation, time from enucleation to organ culture storage and duration in organ culture. Growth curves consistently showed a lag phase followed by a steeper linear growth phase. Donor age, time between death and enucleation, and time between enucleation and organ culture were not correlated to the lag time or the growth rate. Time in organ culture had a significant correlation with the duration of lag time (P = 0.003), but no relationship with the linear growth rate. This study shows that an important factor correlating with growth variation is the duration of corneo‐scleral tissue in organ culture. Interestingly, donor age was not correlated with limbal explant growth. J. Cell. Physiol. © 2012 Wiley Periodicals, Inc. 相似文献
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Amna Sajjad Tatyana Novoyatleva Silvia Vergarajauregui Christian Troidl Ralph T. Schermuly Haley O. Tucker Felix B. Engel 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》2014
Apoptosis, or programmed cell death, is an essential physiological process for proper embryogenesis as well as for homeostasis during aging. In addition, apoptosis is one of the major mechanisms causing cell loss in pathophysiological conditions such as heart failure. Thus, inhibition of apoptosis is an important approach for preventive and therapeutic strategies. Here we show that the histone 3 lysine 4- and lysine 36-specific methyltransferase Smyd2 acts as an endogenous antagonistic player of p53-dependent cardiomyocyte apoptosis. Smyd2 protein levels were significantly decreased in cardiomyocytes upon cobalt chloride-induced apoptosis or myocardial infarction, while p53 expression was enhanced. siRNA-mediated knockdown of Smyd2 in cultured cardiomyocytes further enhanced cobalt chloride-induced cardiomyocyte apoptosis. In contrast, Smyd2 overexpression resulted in marked methylation of p53 and prevented its accumulation as well as apoptotic cell death in an Hsp90-independent manner. Moreover, overexpression, of Smyd2, but not Smyd2Y240F lacking a methyl transferase activity, significantly rescued CoCl2-induced apoptosis in H9c2 cardioblasts. Finally, Smyd2 cardiomyocyte-specific deletion in vivo promoted apoptotic cell death upon myocardial infarction, which correlated with enhanced expression of p53 and pro-apoptotic Bax. Collectively, our data indicate Smyd2 as a cardioprotective protein by methylating p53. 相似文献