Interactions between landscape and local factors inform spatial action planning in post-fire forest environments

Landscape Ecology - Landscape and local factors govern tree regeneration across heterogeneous post-fire forest environments. But their relative influence is unclear—limiting the degree that...     

Diagnostic and public health investigation of Mycobacterium tuberculosis infection in a dog in Ontario,Canada

A 4-y-old, female mixed-breed dog was presented to the Ontario Veterinary College for further evaluation of multiple pulmonary and hepatic masses, intrathoracic lymphadenitis, and recent development of a pyogranulomatous pleural effusion. Along with other comprehensive tests, a thoracic lymph node biopsy was performed, and Mycobacterium tuberculosis complex infection was confirmed by real-time PCR. The dog’s condition declined post-operatively, and euthanasia was elected. Postmortem examination confirmed severe granulomatous pneumonia, hepatitis, intrathoracic and intraabdominal lymphadenitis, omentitis, and nephritis. Line-probe assays performed on samples collected postmortem confirmed the species as M. tuberculosis. 24-loci MIRU-VNTR genotyping, spoligotyping, and whole-genome sequencing revealed relations to known human isolates, but no epidemiologic link to these cases was investigated. Given the concern for potential human exposure during this animal’s disease course, a public health investigation was initiated; 45 individuals were tested for M. tuberculosis exposure, and no subsequent human infections related to this animal were identified. Our case highlights the need for more readily available, minimally invasive testing for the diagnosis of canine mycobacteriosis, and highlights the ability of canid species to act as potential contributors to the epidemiology of M. tuberculosis infections.     

Improving Drought Tolerance of Rice by Designed QTL Pyramiding

Drought is the most important factor limiting rice yields in the rainfed areas of Asia. To overcome the problem, we developed a new strategy ＇designed QTL pyramiding＇ to more efficiently develop drought tolerant （DT） rice cultivars. In the first phase of this strategy, we developed large numbers of introgression lines （ILs） in elite backgrounds using backcross （BC） breeding, each of which carries multiple genomic segments for improved DT from a known donor. Then, we genotyped all ILs with SSR markers to track the genomewide pattern of introgression in the DT ILs of 16 BC populations derived from crosses between 2 recipients （IR64 and Teqing） and four different donors. X^2 tests and linkage disequilibrium analyses of introgression in the DT ILs revealed significant frequency shifts at many loci across the genome and non-random associations at the multilocus level as a result of selection for DT in the ILs, which led us to the discovery of putative genetic networks underlying DT in the ILs. The networks each containing all DT loci detected in ILs from a BC population showed some interesting features.     

Comparative Genomics for Gene Isolation in Legumes

The similarity in gene order between closely related taxa suggests that genomic information from model systems should facilitate gene isolation and characterization in target crops. If this is the case, a great deal of effort and investment can be saved by focusing attention on a few model systems that have appropriate applicability. Pea （Pisura sativum） provides a good test case： its genome is large and the insertion sites for repetitive elements, which comprise the bulk of its genome, are highly polymorphic （Jing et al., 2005; Vershinin et al., 2003）, so we expect a great deal of structural polymorphism between the genomes of Pisum lines. Yet the genetic map of Pisum is essentially coUinear with Medicago （Choi et al., 2004; Kalo et al., 2004）.     

Gene Discovery and Characterization from Non-sequenced Medicinal Plants

Plant-derived secondary metabolites still constitute important resources for currently prescribed drugs and for the discovery of active principles which are effective in new indication areas. Promising compounds are often exclusively found in wild medicinal plants and the classical plant-based pharmaceutical production approach has been hampered by low yields, lack of reproducibility and the high complexity of plant extracts （Rischer and Oksman-Caldentey, 2005）. Influencing the accumulation of target compounds by breeding or genetic engineering is greatly impeded because in most cases the general biosynthetic routes are incompletely understood.     

Mapping QTLs for Yield Stability in Durum Wheat Grown under Different Water Regimes

Among the most important Mediterranean annual crops, durum wheat is widely grown in drought-prone areas. Therefore, improving water-use efficiency （WUE） of durum wheat represents a major breeding goal. IDu-WUE （Improving Durum wheat for Water Use Efficiency and yield stability through physiological and molecular approaches） is a collaborative project among public and private research centres in Italy, Spain and WANA （West Asia and North Africa） countries （Morocco, Tunisia, Syria and Lebanon） funded by the European Union aimed at investigating the genetic variation for WUE and yield stability in durum wheat grown in Mediterranean droughtprone areas. During the first year of the project, a number of morpho-physiological traits （e.g. early vigour, flowering time, leaf rolling, number of fertile tillers, etc.）, WUE, WUE-related traits （e.g. carbon isotope discrimination, canopy temperature, chlorophyll fluorescence, etc.）, yield and its components have been investigated in a RIL population （249 lines） and a collection of ca. 190 durum wheat accessions characterized by a high level of linkage disequilibrium （Maccaferri et al., 2005）,     

Ancient Polyploidy and Modern Crop Plants

The growing set of fully-sequenced angiosperm genomes highlight the role of polyploidy in angiosperm evolution, and suggest that even the high level of importance we had already attributed to this mechanism was inadequate.     

Genetic Diversity of Peanut Core Collection from US Using Simple Sequence Repeats

Groundnut is a member of genus Arachis and the crop is divided into two subspecies and six botanical varieties based on morphological characteristics （Krapovickas and Gregory, 1994）. The International Crops Research Institute for the Semi-Arid Tropics （ICRISAT） holds more than 14 000 groundnut accessions from which a core collection of 1 704 have been developed （Upadhyaya et al., 2003）. Holdbrook et al. （1993） developed a groundnut core collection of 831 accessions from a total of 7 432 US groundnut accessions based on morphological characteristics. The large number and variability of accessions in GenBanks create problems in knowing which germplasm to select for breeding purpose. Only a few established cultivars and elite breeding lines have been utilised in breeding programmes. A core collection is a fraction of accessions from the entire collection which represent most of the available genetic diversity of the species. A core collection can extensively be evaluated and information derived from them can be applied to the whole collection. Identification of DNA markers associated with the botanical varieties of groundnut would be useful in genotyping, germplasm management and evolutionary studies.     

Aurasperone A Inhibits SARS CoV-2 In Vitro: An Integrated In Vitro and In Silico Study

Several natural products recovered from a marine-derived Aspergillus niger were tested for their inhibitory activity against SARS CoV-2 in vitro. Aurasperone A (3) was found to inhibit SARS CoV-2 efficiently (IC₅₀ = 12.25 µM) with comparable activity with the positive control remdesivir (IC₅₀ = 10.11 µM). Aurasperone A exerted minimal cytotoxicity on Vero E6 cells (CC₅₀ = 32.36 mM, SI = 2641.5) and it was found to be much safer than remdesivir (CC₅₀ = 415.22 µM, SI = 41.07). To putatively highlight its molecular target, aurasperone A was subjected to molecular docking against several key-viral protein targets followed by a series of molecular dynamics-based in silico experiments that suggested M^pro to be its primary viral protein target. More potent anti-SARS CoV-2 M^pro inhibitors can be developed according to our findings presented in the present investigation.     

低温等离子体耦合Fe2O3催化剂去除粮食仓储环境中磷化氢

为了探究低温等离子体（Non-Thermal Plasma,NTP）耦合催化剂对粮仓中磷化氢（PH3）的去除效果,该文采用介质阻挡放电低温等离子体与催化剂耦合的反应装置,研究了NTP与Fe2O3催化剂耦合对PH3去除率的影响,并对耦合反应后的催化剂进行表征,分析产物及反应机理。结果表明,载体和催化剂与NTP耦合改变了NTP的放电状态,提高了PH3去除率;不同载体负载Fe2O3后,在输入功率超过53 W时,NTP与Fe2O3催化剂耦合对PH3去除率均高于无填充,Fe2O3/Al2O3与NTP耦合效果最好,去除效率达到了100%。耦合前后催化剂的表征结果表明,耦合反应之后,Fe2O3/Al2O3催化剂的比表面积降低了11.23%,Fe3+/(Fe2++Fe3+)含量提高了21.06%,Osur/(Olatt+Osur+Oads)含量减少了2.24%,Fe含量降低了4.69%,P含量增加了4.34倍。产物分析表明耦合后生成的主要产物为磷酸。研究结果表明NTP耦合Fe2O3/Al2O3催化剂具有很好的PH3去除效果,为粮食仓储行业去除磷化氢提供理论依据。