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1.
In this paper the recent population changes of the Wild Boar in different European countries is analysed through the study of hunting statistics. A simultaneous increase in numbers is observed throughout the whole area during the period 1965–1975. From 1975 onwards the population stabilizes itself apart from in peripheral areas like Finland. Potentially favourable factors which play a part in this process are discussed and certain reproductive and dispersive characteristics which favour its invasive behaviour are discussed. 相似文献
2.
Stopped-flow kinetic studies of the formation of ferrioxamine B were performed. Formation of the complex follows the rate law where Ka is the acid dissociation constant of the iron(III) aquo species in 0.1 M formate buffer. At 25°C k1 = 3.94 × 102M?1 sec?1, k2Ka = 1.18 × 10?1 sec?1, k3 = 3.6 × 10?1 sec?1. Activation parameters for k1 are ΔH≠ = 11.7 kcal mole?1 and ΔS≠ = ?8 cal K?1 mole?1. An associative mechanism is proposed. Attachment of the first chelate ring is the slow step and favorably positions the second chelate ring for attachment. Coordination of two chelate rings favorably positions the third chelate ring for attachment. These results are compared to kinetics of formation of model complexes and to a previous study of the formation of ferrioxamine B in which attachment of the third chelate ring was proposed as the slow step 相似文献
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Melanie Duc Bo Massey Suchinta Arif Shanukie Embuldeniya Karma Nanglu Joseph Bielawski 《PLoS computational biology》2022,18(6)
Undergraduate students from underrepresented backgrounds (e.g., Black, Indigenous, and people of color [BIPOC], members of the Deaf community, people with disabilities, members of the 2SLGBTQIA+ community, from low-income backgrounds, or underrepresented genders) continue to face exclusion and marginalization in higher education. In this piece, authored and edited by a diverse group of Science, Technology, Engineering, and Mathematics (STEM) scholars, we present 10 simple rules for succeeding as an underrepresented STEM undergraduate student, illuminating the “hidden curriculum” of STEM specifically as it relates to the underrepresented undergraduate experience. Our rules begin by encouraging students to embrace their own distinct identities and scientific voices and explain how students can overcome challenges unique to underrepresented students throughout their undergraduate degrees. These rules are derived from a combination of our own experiences navigating our undergraduate STEM degrees and the growing body of literature on improving success for underrepresented students. 相似文献
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A composting experiment was conducted to evaluate the effect of a hyperlignocellulolytic fungal consortium and different nitrogen
amendments on paddy straw composting in terms of changes in physicochemical and biological parameters. A fungal consortium
comprising four lignocellulolytic mesophilic fungal cultures was used as inoculum for bioaugmentation of paddy straw in perforated
pits. The comparative effect of farmyard manure (FYM), soybean trash, poultry litter and urea on the composting process was
evaluated at monthly intervals in terms of physicochemical (pH, EC, available P, C:N ratio and humus content) and biological
(enzymatic and microbial activity) parameters. The compost prepared from bioaugmented paddy straw composting mixture, with
poultry manure as nitrogen supplement attained desirable C:N ratio in 1 month and displayed least phytotoxicity levels along
with higher production of β-1,4-Exoglucanase. The combined activity of the autochthonous composting microbiota as well as the externally applied fungal
inoculum accelerated the composting process of paddy straw. Supplementation of paddy straw with poultry manure in 8:1 ratio
was identified as the best treatment to hasten the composting process. This study highlights the importance of application
of fungal inoculum and an appropriate N-amendment such as poultry manure for preparation of compost using a substrate having
high C:N ratio, such as paddy straw. 相似文献
7.
The ferric uptake regulator (Fur) is a metal-dependent DNA-binding protein that acts as both a repressor and an activator of numerous genes involved in maintaining iron homeostasis in bacteria. It has also been demonstrated in Vibrio cholerae that Fur plays an additional role in pathogenesis, opening up the potential of Fur as a drug target for cholera. Here we present the crystal structure of V. cholerae Fur that reveals a very different orientation of the DNA-binding domains compared with that observed in Pseudomonas aeruginosa Fur . Each monomer of the dimeric Fur protein contains two metal binding sites occupied by zinc in the crystal structure. In the P. aeruginosa study these were designated as the regulatory site (Zn1) and structural site (Zn2). This V. cholerae Fur study, together with studies on Fur homologues and paralogues, suggests that in fact the Zn2 site is the regulatory iron binding site and the Zn1 site plays an auxiliary role. There is no evidence of metal binding to the cysteines that are conserved in many Fur homologues, including Escherichia coli Fur. An analysis of the metal binding properties shows that V. cholerae Fur can be activated by a range of divalent metals. 相似文献
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To understand the synonymous codon usage pattern in mitochondrial genome of Antheraea assamensis, we analyzed the 13 mitochondrial protein‐coding genes of this species using a bioinformatic approach as no work was reported yet. The nucleotide composition analysis suggested that the percentages of A, T, G,and C were 33.73, 46.39, 9.7 and 10.17, respectively and the overall GC content was 19.86, that is, lower than 50% and the genes were AT rich. The mean effective number of codons of mitochondrial protein‐coding genes was 36.30 and it indicated low codon usage bias (CUB). Relative synonymous codon usage analysis suggested overrepresented and underrepresented codons in each gene and the pattern of codon usage was different among genes. Neutrality plot analysis revealed a narrow range of distribution for GC content at the third codon position and some points were diagonally distributed, suggesting both mutation pressure and natural selection influenced the CUB. 相似文献
10.
Mian Abdur Rehman Arif Sajid Shokat Jörg Plieske Martin Ganal Ulrike Lohwasser Yuriy V. Chesnokov Nataliya V. Kocherina Pawan Kulwal Neeraj Kumar Patrick E. McGuire Mark E. Sorrells Calvin O. Qualset Andreas Börner 《The Plant journal : for cell and molecular biology》2021,108(4):960-976
The continuous increase in global population prompts increased wheat production. Future wheat (Triticum aestivum L.) breeding will heavily rely on dissecting molecular and genetic bases of wheat yield and related traits which is possible through the discovery of quantitative trait loci (QTLs) in constructed populations, such as recombinant inbred lines (RILs). Here, we present an evaluation of 92 RILs in a bi-parental RIL mapping population (the International Triticeae Mapping Initiative Mapping Population [ITMI/MP]) using newly generated phenotypic data in 3-year experiments (2015), older phenotypic data (1997–2009), and newly created single nucleotide polymorphism (SNP) marker data based on 92 of the original RILs to search for novel and stable QTLs. Our analyses of more than 15 unique traits observed in multiple experiments included analyses of 46 traits in three environments in the USA, 69 traits in eight environments in Germany, 149 traits in 10 environments in Russia, and 28 traits in four environments in India (292 traits in 25 environments) with 7584 SNPs (292 × 7584 = 2 214 528 data points). A total of 874 QTLs were detected with limit of detection (LOD) scores of 2.01–3.0 and 432 QTLs were detected with LOD > 3.0. Moreover, 769 QTLs could be assigned to 183 clusters based on the common markers and relative proximity of related QTLs, indicating gene-rich regions throughout the A, B, and D genomes of common wheat. This upgraded genotype–phenotype information of ITMI/MP can assist breeders and geneticists who can make crosses with suitable RILs to improve or investigate traits of interest. 相似文献