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排序方式: 共有123条查询结果,搜索用时 15 毫秒
1.
In many disaster settings, top‐down responses emphasise ‘expert‐led’ solutions that often involve relocating disaster‐affected communities. While the intention might be to move people from harm's way and facilitate recovery, failure to attend to local pre‐disaster circumstances as well as the interplay between power, resilience and vulnerability within and around affected communities often sees resettlement reconfigure as displacement or disconnection. This oversight may even usher in a new phase of dispossession and disadvantage for marginalised groups (particularly in colonial settings). This paper explores experiences in Australia, Japan and Taiwan to reflect on what issues of local sociality, local culture and local resilience need to be attended to in framing ‘better’ disaster responses.  相似文献   
2.
In order to analyze the Oslbglu4 phenotype, the inducible promoter of the transgenic rice which knock-down the Oslbglu4 expression was assessed. The result showed that 30 μM dexamethasone(DEX) had the stronger induction effect than 10 μM DEX by β-Glucuronidase (GUS) staining, qRT-PCR further verified the Oslbglu4 gene deletion. The effect of DEX and its solvent absolute ethanol on seed development was measured, and no significant effect was observed. The conclusion is that final concentration of DEX at 30 μM is suitable for pOp6 promoter induction.  相似文献   
3.
为了筛选燕麦田高效安全的除草剂,在山西北部地区开展了田间试验,选取田普除草剂(主要成分为二甲戊灵)为试验药剂,8种不同生态型的燕麦品种为供试品种,检验该除草剂对不同品种产量和安全性的影响。研究结果表明:田普除草剂对藜科、蓼科、禾本科、苋科杂草效果较明显,尤其是对藜科杂草的防治效果最好,最高的达到了100%,而对马齿苋科、菊科、旋花科杂草效果不好;使用田普除草剂处理对燕麦品种的穗长、轮层数、小穗数等性状有一定的抑制作用,对籽实千粒重的有促进作用;本研究中喷施除草剂的处理的平均籽实产量比不喷施除草剂的处理和人工除草处理分别增产70.5%和4.3%。此外,该除草剂未对后茬作物(油菜)产生明显药害作用,可对燕麦-油菜倒茬安全使用。  相似文献   
4.
Peat was employed as a biological filter material for the removal of hydrogen sulphide (H2> S) dimethyl sulphide (Me2S) and methyl mercaptan (MeSH) from odorous ventilation air. Removal of H2S was possible without the need to inoculate the filter material with oxidizing microbes whereas Me2S required inoculation for degradation. The removal of Me2S was decreased as a result of MeSH addition. Liming of the filter material, i.e., addition of calcium hydroxide, increased removal efficiency and activated the oxidation of H2S without any adaptation period. As a consequence of the poor Me2S removal efficiency of natural peat, a limed and inoculated biofilter was needed to purify mixtures of gases containing sulphur. The highest H2S load tested with limed but otherwise natural peat was 136 g-S m-3 day-1, yielding a 99 % reduction. The maximum Me2S elimination capacity with limed and inoculated peat was 175 g-S m-3day-1, but removal became unstable when the load exceeded 150 g-S m-3day-1. The maximum MeSH load tested was 107 g-S m-3day-1, yielding 98 % removal.  相似文献   
5.
Bäck  Jaana  Turunen  Minna  Ferm  Ari  Huttunen  Satu 《Water, air, and soil pollution》1997,100(1-2):119-132
Scots pine (Pinus sylvestris) needles from forest sites differing in distance from big fur farms emitting large amounts of ammonia and ammonium (=NHy) were examined by scanning and transmission electron microscopy. Specific features indicating an ammonium-nitrogen overload, such as an abundance of needle surface organisms and modifications in cellular and wax structures, were classified. Throughout the study area (up to 1000 m from the farms), mesophyll cells had thin cytoplasm and folding plasmalemma indicating frost damage. Phloem damage attributable to a possible nutrient imbalance was also observed. Chloroplast membranes were undulating and the occurrence of leaf surface organisms (e.g. aerophilic algae) was more abundant at the closest sites. The changes were related both to the direct effects of dry NHy deposition on the needles, and to the effects operating via soil acidification. The needle epicuticular waxes proved to be structurally rather inert against the influence of ammonium compounds, since no significant changes due to NHy were observed.  相似文献   
6.
The Finnish Healthy Hooves project was set up to determine the frequency of, and risk factors for various hoof lesions in Finnish dairy herds. Data were collected in the years 2003 and 2004. A large dataset of over 74,000 cow-level observations recorded by hoof trimmers was merged with production data from the Finnish Agricultural Data Processing Centre Ltd. Ultimately, data from a single lactation from each of 16,792 cows in 703 herds were used for the analyses in this paper. Three-level hierarchical logistic models with hoof trimmer and farms (within hoof trimmer) as random effects were fit to data sets of tie stall (TS) and loose housing (LH) herds separately. The outcome of interest was the presence or absence of a sole ulcer in one or more legs of a cow during the lactation of interest.Cows examined once had a risk of sole ulcer 5.23% in tie stall herds and 7.58% in LH herds. As the number of examinations increased the odds of a diagnosis of sole ulcer increased substantially (2 and 3+ examinations had odds ratios (ORs) of 1.42 and 3.42 in TS herds and 2.77 and 6.89 in LH herds). Breed had a large effect on the risk of sole ulcer with Holsteins 2.89 times more likely to be affected than Ayrshires in TS herds and 2.94 times in LH herds. In TS herds, the presence of other hoof lesions such as haemorrhages (OR = 2.97), heel-horn erosions (OR = 2.10) and corkscrew claw (OR = 2.83) increased the risk of a sole ulcer developing. In LH herds, only haemorrhages (OR = 1.80) were a significant risk factor when parity was ≥2. In TS herds, use of mats (compared to hard flooring) significantly reduced the risk of sole ulcers (OR = 0.49). The effect of parity on the risk of sole ulcer was greatest when parity ≥4 but this effect was only significant in tie stalls (OR = 1.86).When analyses were restricted to cows with parity ≥2, similar results were obtained for the risk factors identified above. In addition, parity became highly significant in TS and LH (OR 2.31 and 2.23, respectively when parity was 4+). In TS herds, herd average milk production was significantly associated with a decrease risk of sole ulcer (OR = 1.28 per 1000 kg decrease) but there was no effect of production at the cow level (measured as deviation from the herd mean). No significant effects of production were observed in LH herds.  相似文献   
7.
支持细胞对维持精子形成过程中的微环境起决定作用,它可以通过分泌功能、细胞间连接形成的血睾屏障功能以及吞噬功能等来促进精子的形成过程,其发育异常会导致不同程度的雄性生殖缺陷。基于支持细胞在雄性动物生殖过程中的作用,体外培养高纯度支持细胞可成为研究睾丸两大核心功能-精子发生和性激素分泌功能相关调节机制重要的细胞模型。此外,体外培养睾丸支持细胞也可作为生殖毒理学等新兴热点领域的细胞模型,为评估和研究环境因素对雄性生殖的影响提供便利。因此,作者系统地归纳、总结了目前关于动物支持细胞生物功能的研究及常用的体外分离纯化、培养及鉴定方法,以期为利用动物支持细胞开展雄性生殖领域的研究提供参考。  相似文献   
8.
潘敏娜  郑常祥 《种子》2017,(2):41-44
在玉米育种中以GCA,SCA为指标选择玉米二环系的源杂交种作为基础材料来选系,从而选择优良的玉米自交系和杂交组合,本研究结果表明,这种选育玉米自交系的方法是可行和有效的.  相似文献   
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