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Molecular and Cellular Biochemistry - Perinatal asphyxia (PA)-induced brain injury may present as hypoxic-ischemic encephalopathy in the neonatal period, and long-term sequelae such as spastic...  相似文献   
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Molecular Biology Reports - Stripe rust and leaf rust are among the most devastating diseases of wheat, limiting its production globally. Wheat wild relatives harbour genetic diversity for new...  相似文献   
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This study was conducted to investigate the effect of alcohols viz., ethanol, methanol and n-butanol at different concentrations not only on the vase life of Calendula officinalis L. cut flowers but also to record changes in metabolites like starch content and amount of sugars, and activities of α-amylase, and antioxidant enzymes like peroxidase and superoxide dismutase as well as lipid peroxidation. Ethanol as holding solution significantly increased the vase life as compared to other treatments or the control. n-Butanol shortened vase life and caused the flower stem to fold, whereas ethanol and methanol individually delayed drying up and petals dried slowly from their tips. Significant increments in solution uptake, moisture content and flower diameter were noticed with 2 % ethanol followed by 2 % methanol. Cut scapes having 2 % ethanol exhibited maximum amount of starch and considerably lower amount of reducing and non-reducing sugars. This treatment not only brings down the specific activities of α-amylase and peroxidase but also decreases the process of lipid peroxidation. Effectiveness of methanol (2 %) is evident just after ethanol application (2 %). Lowest concentrations of ethanol and methanol also show relatively higher level of SOD activity in cut flowers of Calendula officinalis.  相似文献   
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Background

The development in the deinking process has made recycled fiber a major part of the raw material for pulp and paper industry. Enzymes have revolutionized the deinking process obtaining brightness levels surpassing conventional deinking processes. This study explores the deinking efficiencies of bacterial alkalophilic laccase (L) and xylanase (X) enzymes along with physical deinking methods of microwaving (MW) and sonication (S) for recycling of old newsprint (ONP).

Methods and Results

The operational parameters viz. enzyme dose, pH and treatment time for X and L deinking were optimized statistically using Response Surface Methodology. Laccase did not require any mediator supplementation for deinking. Deinking of ONP pulp with a combination of xylanase and laccase enzymes was investigated, and fiber surface composition and morphological changes were studied using X-ray diffraction, fourier transform infrared spectroscopy and scanning electron microscopy. Compared to the pulp deinked with xylanase (47.9%) or laccase (62.2%) individually, the percentage reduction of effective residual ink concentration (ERIC) was higher for the combined xylanase/laccase-deinked pulp (65.8%). An increase in brightness (21.6%), breaking length (16.5%), burst factor (4.2%) tear factor (6.9%), viscosity (13%) and cellulose crystallinity (10.3%) along with decrease in kappa number (22%) and chemical consumption (50%) were also observed. Surface appeared more fibrillar along with changes in surface functional groups. A combination of physical and enzymatic processes (S-MW-XL) for deinking further improved brightness (28.8%) and decreased ERIC (73.9%) substantially.

Conclusion

This is the first report on deinking of ONP with laccase without any mediator supplementation. XL pretreatment resulted in marked improvement in paper quality and a new sequence being reported for deinking (S-MW-XL) will contribute further in decreasing chemical consumption and making the process commercially feasible.  相似文献   
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Plasmodium vivax is the most widely distributed human parasite and the main cause of human malaria outside the African continent. However, the knowledge about the genetic variability of P. vivax is limited when compared to the information available for P. falciparum. We present the results of a study aimed at characterizing the genetic structure of P. vivax populations obtained from pregnant women from different malaria endemic settings. Between June 2008 and October 2011 nearly 2000 pregnant women were recruited during routine antenatal care at each site and followed up until delivery. A capillary blood sample from the study participants was collected for genotyping at different time points. Seven P. vivax microsatellite markers were used for genotypic characterization on a total of 229 P. vivax isolates obtained from Brazil, Colombia, India and Papua New Guinea. In each population, the number of alleles per locus, the expected heterozygosity and the levels of multilocus linkage disequilibrium were assessed. The extent of genetic differentiation among populations was also estimated. Six microsatellite loci on 137 P. falciparum isolates from three countries were screened for comparison. The mean value of expected heterozygosity per country ranged from 0.839 to 0.874 for P. vivax and from 0.578 to 0.758 for P. falciparum. P. vivax populations were more diverse than those of P. falciparum. In some of the studied countries, the diversity of P. vivax population was very high compared to the respective level of endemicity. The level of inter-population differentiation was moderate to high in all P. vivax and P. falciparum populations studied.  相似文献   
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