Photoperiod and variation in life history traits in core and peripheral populations in the damselfly Lestes sponsa

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The action of air ions on bacteria. I. Protective and lethal effects on suspensions of Staphylococci in droplets

Techniques have been devised for studying quantitatively the effects of air ions on microorganisms suspended in small drops. In smog-contaminated atmospheres moderate concentrations of positive and negative air ions exerted a protective effect on staphylococci by delaying the drop in pH customarily observed and by diminishing the rate of evaporation. In clean air higher concentrations of positive and negative air ions accelerated the rate of death of staphylococci apparently by direct action on the cells and by increasing the rate of evaporation. Air ion action in these experiments did not involve cell agglutination or direct radiation from the radioactive isotopes employed.     

Whole Exome Sequencing in Atrial Fibrillation

Atrial fibrillation (AF) is a morbid and heritable arrhythmia. Over 35 genes have been reported to underlie AF, most of which were described in small candidate gene association studies. Replication remains lacking for most, and therefore the contribution of coding variation to AF susceptibility remains poorly understood. We examined whole exome sequencing data in a large community-based sample of 1,734 individuals with and 9,423 without AF from the Framingham Heart Study, Cardiovascular Health Study, Atherosclerosis Risk in Communities Study, and NHLBI-GO Exome Sequencing Project and meta-analyzed the results. We also examined whether genetic variation was enriched in suspected AF genes (N = 37) in AF cases versus controls. The mean age ranged from 59 to 73 years; 8,656 (78%) were of European ancestry. None of the 99,404 common variants evaluated was significantly associated after adjusting for multiple testing. Among the most significantly associated variants was a common (allele frequency = 86%) missense variant in SYNPO2L (rs3812629, p.Pro707Leu, [odds ratio 1.27, 95% confidence interval 1.13–1.43, P = 6.6x10^-5]) which lies at a known AF susceptibility locus and is in linkage disequilibrium with a top marker from prior analyses at the locus. We did not observe significant associations between rare variants and AF in gene-based tests. Individuals with AF did not display any statistically significant enrichment for common or rare coding variation in previously implicated AF genes. In conclusion, we did not observe associations between coding genetic variants and AF, suggesting that large-effect coding variation is not the predominant mechanism underlying AF. A coding variant in SYNPO2L requires further evaluation to determine whether it is causally related to AF. Efforts to identify biologically meaningful coding variation underlying AF may require large sample sizes or populations enriched for large genetic effects.     

Dithiocarbamates with potent inhibitory activity against the Saccharomyces cerevisiae β-carbonic anhydrase

Dithiocarbamates (DTCs) prepared from primary or secondary amines, which incorporated amino/hydroxyl-alkyl, mono-/bicyclic aliphatic/heterocyclic rings based on the quinuclidine, piperidine, hydroxy-/carboxy-/amino-substituted piperidine, morpholine and piperazine scaffolds, were investigated for the inhibition of α- and β-carbonic anhydrases (CAs, EC 4.2.1.1) of pharmacologic relevance, such as the human (h) isoform hCA I and II, as well as the Saccharomyces cerevisiae β-CA, scCA. The yeast and its β-CA were shown earlier to be useful models of pathogenic fungal infections. The DTCs investigated here were medium potency hCA I inhibitors (K_Is of 66.5–910?nM), were more effective as hCA II inhibitors (K_Is of 8.9–107?nM) and some of them showed excellent, low nanomolar activity against the yeast enzyme, with inhibition constants ranging between 6.4 and 259?nM. The detailed structure activity relationship for inhibition of the yeast and human enzymes is discussed. Several of the investigated DTCs showed excellent selectivity ratios for inhibiting the yeast over the human cytosolic CA isoforms.     

Aspects of Scotia Sea zooplankton

Information on small scale distributions of three species of Antarctic zooplankton is reviewed. Aggregations of the euphausiid Euphausia superba , the tunicate Salpa thompsoni , and the amphipod Parathemisto gaudichaudii are compared, and the manner in which such aggregations mav arise is discussed. A possible relationship between swarming and feeding activity in E. superba is suggested in which krill are thought to be dispersed whilst feeding but that on repletion they swarm. It is thought that this may account for this species' irregular spatial distribution as recorded bv previous expeditions. A further consequence of this theory is that during the Winter swarming will be minimal.     

Sequencing of 15 622 gene‐bearing BACs clarifies the gene‐dense regions of the barley genome

Barley (Hordeum vulgare L.) possesses a large and highly repetitive genome of 5.1 Gb that has hindered the development of a complete sequence. In 2012, the International Barley Sequencing Consortium released a resource integrating whole‐genome shotgun sequences with a physical and genetic framework. However, because only 6278 bacterial artificial chromosome (BACs) in the physical map were sequenced, fine structure was limited. To gain access to the gene‐containing portion of the barley genome at high resolution, we identified and sequenced 15 622 BACs representing the minimal tiling path of 72 052 physical‐mapped gene‐bearing BACs. This generated ~1.7 Gb of genomic sequence containing an estimated 2/3 of all Morex barley genes. Exploration of these sequenced BACs revealed that although distal ends of chromosomes contain most of the gene‐enriched BACs and are characterized by high recombination rates, there are also gene‐dense regions with suppressed recombination. We made use of published map‐anchored sequence data from Aegilops tauschii to develop a synteny viewer between barley and the ancestor of the wheat D‐genome. Except for some notable inversions, there is a high level of collinearity between the two species. The software HarvEST:Barley provides facile access to BAC sequences and their annotations, along with the barley–Ae. tauschii synteny viewer. These BAC sequences constitute a resource to improve the efficiency of marker development, map‐based cloning, and comparative genomics in barley and related crops. Additional knowledge about regions of the barley genome that are gene‐dense but low recombination is particularly relevant.     

饲用复合酶产生菌好食脉孢霉发酵条件研究

利用好食脉孢霉发酵蔗渣、麸皮、木薯渣等工农业有机废料 ,生产可用于配制饲用复合酶制剂的酶制品。合适的培养基配方为每千克固体料中含蔗渣 10 0 g、麸皮 6 0 0g、木薯渣 30 0 g ,并添加 2 0g复合氮源和适量的磷酸盐 ,培养基含水量为固体料干重的两倍 ;接种后先在 34℃以下培养 2d ,然后在 37℃发酵 2～ 3d ,发酵过程中无光照、空气供应充分、培养基中含水量损失不能太大。发酵结束后固体曲中纤维素酶活力 (CMC +C1) 1,75 9mg/g/h ,糖化酶活力 3,110mg/ g     

Genome resources for climate‐resilient cowpea,an essential crop for food security

Cowpea (Vigna unguiculata L. Walp.) is a legume crop that is resilient to hot and drought‐prone climates, and a primary source of protein in sub‐Saharan Africa and other parts of the developing world. However, genome resources for cowpea have lagged behind most other major crops. Here we describe foundational genome resources and their application to the analysis of germplasm currently in use in West African breeding programs. Resources developed from the African cultivar IT97K‐499‐35 include a whole‐genome shotgun (WGS) assembly, a bacterial artificial chromosome (BAC) physical map, and assembled sequences from 4355 BACs. These resources and WGS sequences of an additional 36 diverse cowpea accessions supported the development of a genotyping assay for 51 128 SNPs, which was then applied to five bi‐parental RIL populations to produce a consensus genetic map containing 37 372 SNPs. This genetic map enabled the anchoring of 100 Mb of WGS and 420 Mb of BAC sequences, an exploration of genetic diversity along each linkage group, and clarification of macrosynteny between cowpea and common bean. The SNP assay enabled a diversity analysis of materials from West African breeding programs. Two major subpopulations exist within those materials, one of which has significant parentage from South and East Africa and more diversity. There are genomic regions of high differentiation between subpopulations, one of which coincides with a cluster of nodulin genes. The new resources and knowledge help to define goals and accelerate the breeding of improved varieties to address food security issues related to limited‐input small‐holder farming and climate stress.