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11.
Almas Fakhrah Hassan Adeel Bibi Arfa Ali Masab Lateef Sadia Mahmood Tariq Rasheed Awais Quraishi Umar Masood 《Plant and Soil》2018,431(1-2):371-387
Plant and Soil - Extreme climate events, including flooding and prolonged drought, may establish long-lasting (legacy) effects on soil abiotic and biotic properties, potentially influencing soil... 相似文献
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Raja Noor Zaliha Raja Abd Rahman Thean Chor Leow Abu Bakar Salleh Mahiran Basri 《BMC microbiology》2007,7(1):77
Background
Thermophilic Bacillus strains of phylogenetic Bacillus rRNA group 5 were described as a new genus Geobacillus. Their geographical distribution included oilfields, hay compost, hydrothermal vent or soils. The members from the genus Geobacillus have a growth temperatures ranging from 35 to 78°C and contained iso-branched saturated fatty acids (iso-15:0, iso-16:0 and iso-17:0) as the major fatty acids. The members of Geobacillus have similarity in their 16S rRNA gene sequences (96.5–99.2%). Thermophiles harboring intrinsically stable enzymes are suitable for industrial applications. The quest for intrinsically thermostable lipases from thermophiles is a prominent task due to the laborious processes via genetic modification. 相似文献15.
Jamil?Ahmed?SoomroEmail author Zeeshan?Noor?Shaikh Tennegedara?Buhary?Saheer Suhail?Ahmed?Bijarani 《International breastfeeding journal》2016,11(1):24
Background
Breastfeeding is considered to be an important measure to achieve optimum health outcomes for children, women’s return to work has frequently been found to be a main contributor to the early discontinuation of breastfeeding. The aim of the study is to assess workplace breastfeeding support provided to working mothers in Pakistan.Method
A workplace based cross-sectional survey was conducted from April through December 2014. Employers from a representative sample of 297 workplaces were interviewed on pre-tested and structured questionnaire. The response rate was 93.7 %. Prevalence of workplace breastfeeding facilities were assessed in the light of World Alliance for Breastfeeding Action (WABA) guidelines.Results
Among non-physical facilities, all workplaces offered 3 months paid maternity leave, 45 % of the sites were offering task adjustment to mothers during lactation period. Only 15 % of the sites were offering breastfeeding breaks to working mothers. Physical facilities that include a breastfeeding corner, refrigerator for storing breast milk, breast milk pump and nursery for childcare were provided in less than 7 % of the sites. Multinational organizations provided better support compared to national organizations.Conclusion
Support for continuation of breastfeeding by working women at workplaces is inadequate; hence, women discontinue breastfeeding earlier than planned. Policies need to be developed and enforced, employers and employees need to be educated and supportive environment needs to be created to encourage and facilitate breastfeeding friendly worksite environment.16.
Summary The occurrence of cells resembling mammalian Langerhans cells in the avian epidermis was studied by ATPase histochemistry, Ia immunoreactivity and electron microscopy. The existence of MHC class II antigen-(Ia) expressing, ATPase-positive dendritic cells, which are ultrastructurally similar to mammalian Langerhans cells except for the absence of Birbeck granules, was demonstrated. These cells may be a basic component of the immune system of birds. 相似文献
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The genetics of hybrid male sterility between the allopatric species pair Drosophila persimilis and D. pseudoobscura bogotana: dominant sterility alleles in collinear autosomal regions 下载免费PDF全文
F(1) hybrid male sterility is thought to result from interactions between loci on the X chromosome and dominant-acting loci on the autosomes. While X-linked loci that contribute to hybrid male sterility have been precisely localized in many animal taxa, their dominant autosomal interactors have been more difficult to localize precisely and/or have been shown to be of relatively smaller effect. Here, we identified and mapped at least four dominant autosomal factors contributing to hybrid male sterility in the allopatric species pair Drosophila persimilis and D. pseudoobscura bogotana. Using these results, we tested predictions of reduced recombination models of speciation. Consistent with these models, three of the four QTL associated with hybrid male sterility occur in collinear (uninverted) regions of these genomes. Furthermore, these QTL do not contribute significantly to hybrid male sterility in crosses between the sympatric species D. persimilis and D. pseudoobscura pseudoobscura. The autosomal loci identified in this study provide the basis for introgression mapping and, ultimately, for molecular cloning of interacting genes that contribute to F(1) hybrid sterility. 相似文献
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Ravigadevi Sambanthamurthi Siti Hasnah Parman Mohd. Roslan Md. Noor 《Plant Cell, Tissue and Organ Culture》1996,46(1):35-41
Procedures are deseribed for the efficient isolation of protoplasts from a variety of oil palm (Elaeis guineensis Jacq.) tissues. Various factors including donor source, composition of enzyme mixture and culture medium affected the yield and viability of the protoplasts Polyembryogenic cultures of oil palm were the most suitable starting material in terms of yield, viability and metabolic competence. Pectolyase Y-23 in association with cellulase and hemicellulase was required for the efficient release of protoplasts from the oil palm tissues. Limited cell division to form microcallus was observed at very low frequency (<0.01%) when glutathione and catalase were incorporated in the culture medium.Abbreviations 2,4-d
dichlorophenoxyacetic acid
- DTT
dithiothreitol
- MES
2[N-morpholino] ethanesulphonic acid
- NAA
1-naphthalene acetic acid
- PVP
polyvinylpyrrolidone 相似文献
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Bibi NS Gavara PR Soto Espinosa SL Grasselli M Fernández-Lahore M 《Biotechnology progress》2011,27(5):1329-1338
The preparation of megaporous bodies, with potential applications in biotechnology, was attempted by following several strategies. As a first step, naive and robust scaffolds were produced by polymerization of selected monomers in the presence of a highly soluble cross‐linker agent. Ion‐exchange function was incorporated by particle embedding, direct chemical synthesis, or radiation‐induced grafting. The total ionic capacity of such systems was 1.5 mmol H+/g, 1.4 mmol H+/g, and 17 mmol H+/g, respectively. These values were in agreement with the ability to bind model proteins: observed dynamic binding capacity at 50% breakthrough was ?7.2 mg bovine serum albumin/g, ?7.4 hen egg‐white lysozyme (HEWL) mg/g, and ?108 HEWL mg/g. In the later case, total (static) binding capacity reached 220 mg/g. It was observed that the structure and size of the megapores remained unaffected by the grafting procedure which, however, allowed for the highest protein binding capacity. Lysozyme supported on grafted body showed extensive clarification activity against a Micrococcus lysodekticus suspension in the flow‐through mode, i.e., 90% destruction of suspended microbial cells was obtained with a residence time ≈ 18 min. Both protein capture and biocatalysis applications are conceivable with the 3D‐megaporous materials described in this work. © 2011 American Institute of Chemical Engineers Biotechnol. Prog., 2011 相似文献