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91.
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This study estimates the abatement cost of greenhouse gas (GHG) emissions for a unit of electricity generated in the UK from wood pellets imported from Southern USA. We assumed that only pulpwood obtained from loblolly pine (Pinus taeda) plantations was used for manufacturing exported wood pellets. The use of imported wood pellets for electricity generation could save at least 69.9 % of GHG emissions relative to coal-based electricity in the UK. The average unit production cost of electricity generated from imported wood pellets (US$222.3 MWh?1) was higher by 30.0 % than the unit production cost of electricity generated from coal (US$171.0 MWh?1) without any price support. In the presence of payments from the established price support mechanisms of Renewable Obligation Certificates (ROCs) and Levy Exemption Certificates (LECs), the unit production cost of electricity generated from imported wood pellets (US$142.9 MWh?1) was lower by about 16.0 % than the unit production cost of electricity generated from coal. Policy makers should consider 1 MWh of electricity generated from imported wood pellets equivalent to 0.58 ROCs or 0.71 ROCs in presence and absence of payments from LECs, respectively. This will ensure zero abatement cost and lead to economic efficiency in reducing GHG emissions. However, a more in-depth analysis focusing on the market risks for power-generating companies and other wood pellet supply chains is required before modifying existing equivalency factors for ensuring continuous use of imported wood pellets for displacing coal-based electricity in the UK. 相似文献
93.
Summary Experiments on nutrient and staled agar were carried out to investigate the mycoparasitic activity of some fusaria againstRhizoctonia solani Kühn. Penetration and coiling byFusarium oxysporum Sch.,F. semitectum Berk & Rav. andF. udum Butler in and around theR. solani hyphae was observed. Lysis ofF. udum hyphae was observed inside theR. solani hyphae showing the reverse of the normal direction of necrotrophic mycoparasitic relationships. The mycoparasitic activity ofFusarium spp. was much affected in staled agar plates. 相似文献
94.
The lateral bud meristems of Tradescantia paludosa show a characteristic cytohistological zonation during dormancy. The cells comprising this so called ‘zone of inhibition’, which is located at the extreme tip of the bud apex, rarely synthesize nuclear DNA or undergo mitotic division. These nuclei are as large as prophase nuclei, yet contain only telophase (2C) amounts of DNA and significantly lower amounts of histone as compared to the 2C nuclei of the actively dividing cells.Ultrastructural observations of the nuclei in the ‘zone of inhibition’ show that a large proportion of the chromatin is organized as less condensed, diffuse, euchromatin fibrils; however, the chromatin of the actively dividing nuclei of the cells outside the ‘zone of inhibition’ or in the released bud meristems is organized to a greater extent as condensed clumps of heterochromatin. When the dormancy is released, the nuclei in the ‘zone of inhibition’ synthesize DNA and histone and undergo cell division in approx. 4 days. Striking changes in the organization of chromatin fibrils take place during this transition period. The diffuse chromatin fibrils of the nuclei in the ‘zone of inhibition’ progressively become more and more condensed as the cell prepares to undergo the first mitotic division after the release of dormancy. This change which is coupled with the synthesis of histones in the nuclei of the ‘zone of inhibition’ suggests a prominent structural role of these basic proteins in the organization of the chromatin. The large volume of 2C nuclei of the ‘zone of inhibition’ seems, therefore, to result not from a great nuclear mass, but probably from a relatively small degree of condensation of chromatin. 相似文献
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Mitesh Dwivedi Naresh C. Laddha Prateek Arora Yogesh S. Marfatia Rasheedunnisa Begum 《Pigment cell & melanoma research》2013,26(4):586-591
The aim of present study was to evaluate CD4+/CD8+ ratio and CD4+CD25hiFoxP3+ Tregs in GV patients with reference to their effect on disease onset and progression. Flow cytometry was used for determination of CD4+/CD8+ ratio and Tregs in 82 patients and 50 controls. CD8+ T‐cell counts were significantly higher in GV patients as compared with controls (p = 0.003). Active GV patients showed higher CD8+ T‐cell counts compared with stable GV patients (p = 0.001). The CD4+/CD8+ ratio decreased significantly in patients as compared with controls (p = 0.001). Moreover, the ratio in active GV patients significantly lowered as compared with stable GV patients (p = 0.002). Significant decrease in Treg cell percentage and counts in GV patients was observed compared with controls (p = 0.009, p = 0.008) with significant reduction in FoxP3 expression (p = 0.024). Treg cell percentage and counts were significantly decreased in active GV patients compared with stable GV patients (p = 0.007, p = 0.002). Our results suggest that an imbalance of CD4+/CD8+ ratio and natural Tregs in frequency and function might be involved in the T‐cell mediated pathogenesis of GV and its progression. 相似文献
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The deficiency of keto acid decarboxylase in maple syrup urine disease results in the accumulation of branched chain amino acids and their corresponding keto acids in tissues and body fluids. The effects of abnormal metabolites were investigated on neurotransmitter receptor binding in rat brain. alpha-Keto acids caused selective in vitro decrease in alpha-adrenergic, beta-adrenergic receptor binding in synaptosomal preparations from rat brain. No significant changes were observed in binding of cholinergic, GABA, and dopamine receptors binding in appropriate rat brain preparations. These results indicate that selective inhibition of adrenergic receptor binding by branched chain keto acids may presumably account for neural abnormality in maple syrup urine disease. 相似文献
100.
Khursheed Ali Faizan Abul Qais Sourabh Dwivedi Eslam M. Abdel-Salam Sabiha M. Ansari Quaiser Saquib 《Journal of biomolecular structure & dynamics》2018,36(10):2530-2542
Titanium dioxide nanoparticles (TiO2-NPs) interaction with human serum albumin (HSA) and DNA was studied by UV–visible spectroscopy, spectrofluorescence, circular dichroism (CD), and transmission electron microscopy (TEM) to analyze the binding parameters and protein corona formation. TEM revealed protein corona formation on TiO2-NPs surface due to adsorption of HSA. Intrinsic fluorescence quenching data suggested significant binding of TiO2-NPs (avg. size 14.0 nm) with HSA. The Stern–Volmer constant (Ksv) was determined to be 7.6 × 102 M?1 (r2 = 0.98), whereas the binding constant (Ka) and number of binding sites (n) were assessed to be 5.82 × 102 M?1 and 0.97, respectively. Synchronous fluorescence revealed an apparent decrease in fluorescence intensity with a red shift of 2 nm at Δλ = 15 nm and Δλ = 60 nm. UV–visible analysis also provided the binding constant values for TiO2-NPs–HSA and TiO2-NPs-DNA complexes as 2.8 × 102 M?1 and 5.4 × 103 M?1. The CD data demonstrated loss in α-helicity of HSA and transformation into β-sheet, suggesting structural alterations by TiO2-NPs. The docking analysis of TiO2-NPs with HSA revealed its preferential binding with aromatic and non-aromatic amino acids in subdomain IIA and IB hydrophobic cavity of HSA. Also, the TiO2-NPs docking revealed the selective binding with A-T bases in minor groove of DNA. 相似文献