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排序方式: 共有433条查询结果,搜索用时 9 毫秒
81.
Mathieu Lalumiere Dany H. Gagnon Jessica Hassan Guillaume Desroches Raphael Zory Didier Pradon 《Journal of electromyography and kinesiology》2013,23(6):1434-1445
High upper extremity (U/E) demands are required when manual wheelchair users (MWUs) with spinal cord injury (SCI) ascend curbs; this may contribute to the risk of developing U/E musculoskeletal impairments. The aim of this study was to compare movement strategies (kinematics), mechanical loads (kinetics) and muscular demand (EMG) at the non-dominant U/E among 15 MWUs with SCI when ascending curbs of 4 cm (3 trials), 8 cm (3 trials) and 12 cm high (3 trials) from a starting line set 3 m before the curb. Biomechanical data was collected during three trials for each height. The curb ascent task was divided into three adjustment phases: caster pop, rear-wheel ascent and post-ascent. The greatest effort was generated by the shoulder flexors and internal rotators as well as the elbow flexors. A significant difference (p < 0.0167) between the curb heights was found for most outcome measures studied: movement excursion, net joint moments and muscular utilization ratio (MUR) of the main muscles increased with the higher curb heights, mainly around the shoulder joint. These results provide insight that aside from adhering to a highly structured training method for wheelchair curb ascent, rehabilitation professionals need to propose task-specific strength training programs based on the demands documented in this study and continue to advocate for physically accessible environments. 相似文献
82.
Realizing the stable operation of an eco-industrial park (EIP) as a complex system consisting of a variety of the enterprises and embedded relations is challenging. The topological structure plays an important role to understand the balance of network resilience and eco-efficiency in the operation process of a given EIP. In this paper, Ningdong Coal Chemical Eco-industrial Park (Ningdong CCEIP) is used as a case study in Ningxia Hui Autonomous Region of China. Based on complex network theory, we focus on topological characteristics analysis of symbiotic network from the perspective of resilience. Results reveal that Ningdong CCEIP has scale-free characteristics as well as the small world ones. Compared with the node-level metrics, the important degree of node considering ecological factor is a more crucial index measuring the importance of a particular node in the network. The removal of top 10% node contributes to 60% decrease of network efficiency, which indicates the decline of resilience in the studied case. Protecting the most important nodes is critical to safeguard the potential “vulnerability” in the development of EIPs. This study can help us better understand the strategies for avoiding disruptions, improving the resilience of EIP and safeguarding the stable operation. 相似文献
83.
Pseudomonas frederiksbergensis ERDD5:01 is a psychrotrophic bacteria isolated from the glacial stream flowing from East Rathong glacier in Sikkim Himalaya. The strain showed survivability at high altitude stress conditions like freezing, frequent freeze-thaw cycles, and UV-C radiations. The complete genome of 5,746,824 bp circular chromosome and a plasmid of 371,027 bp was sequenced to understand the genetic basis of its survival strategy. Multiple copies of cold-associated genes encoding cold active chaperons, general stress response, osmotic stress, oxidative stress, membrane/cell wall alteration, carbon storage/starvation and, DNA repair mechanisms supported its survivability at extreme cold and radiations corroborating with the bacterial physiological findings. The molecular cold adaptation analysis in comparison with the genome of 15 mesophilic Pseudomonas species revealed functional insight into the strategies of cold adaptation. The genomic data also revealed the presence of industrially important enzymes. 相似文献
84.
河南鸡公山国家级自然保护区悬钩子属植物资源开发利用研究 总被引:5,自引:0,他引:5
通过对河南省鸡公山国家级自然保护区悬钩子属植物资源的系统调查研究,发现该保护区有悬钩子属植物15种和1变种,且资源蕴藏量大。它们在食品、医药及工业等方面都有很重要的用途,有较大的开发利用潜力,尤其是其中的山莓Rubus corchorifolius L.f.、茅莓R.parvifolius L.等食用、药用具佳,更可作为工业原料用于酿酒和提制栲胶,具有很高的商品开发价值。如能有计划地加以开发利用,对当地经济发展将会起到积极的促进作用。 相似文献
85.
We set out to describe a new and efficient route for preparing Ulipristal acetate with a good yield. The selected epoxidization conditions gave out 80% of 5α,10α-epoxide 2a in the two diastereoisomers which greatly improved the yield of 11β-substituted isomer 4a. And phenyl–sulfinyl compound 6 was synthesized from ketone 5 directly treated with phenylsulfenyl chloride in the presence of triethylamine. These synthetic procedures is only 8 steps, less than currently reported in the literature, but more suitable for industrial process. 相似文献
86.
产业发展离不开产业政策的制定与发布,产业政策对于产业具有导向性与支持性,其制定主体主要包括中央政府和地方政府。以生物产业为例,采用计量分析的方法,搜集并整理了中央政府以及湖北、深圳、重庆、上海、北京五个地方政府颁布的生物产业政策,对其外部属性特征进行差异性分析,同时对多份国家层面的生物产业结构性政策运用内容分析的方法,进行政策工具分类分析,并构建了“政策工具-生物产业发展阶段”二维政策工具分析框架,探讨不同产业发展阶段之间政策工具使用的差异性。研究发现,中央政府与地方政府生物产业政策密集发布年份存在差异,且与生物产业发展关键节点有关联;国家层面生物产业政策不同类型政策工具使用频率差距较大,以环境型政策工具为主,较少使用需求型政策工具。针对研究结果,从我国生物产业发展情况及区域间差异的角度提出了相关政策建议。 相似文献
87.
Eguchi M Miyazaki T Masatsuji-Kato E Tsuzuki T Oribe T Miwa N 《Molecular and cellular biochemistry》2003,252(1-2):17-23
To search a regimen for prevention of post-ischemic reperfusional (I/R) injuries, I/R in the liver was induced by 30-min clamping and subsequent unfastening of the portal vein of a rat, which underwent previous intravenous administration with ascorbic acid (Asc) of 1 mg/kg or the autooxidation-resistant pro-vitamin C, 2-O-alpha-D-glucosylated Asc (Asc2G) or 2-O-phosphorylated Asc (Asc2P) of 1 mg Asc equivalent/kg from the viewpoint of utilization of antioxidants that can promptly scavenge I/R-derived reactive oxygen species. The administration with Asc, Asc2P or Asc2G prevented some features of hepatic I/R injuries such as release of hepatic marker enzymes GOT and GPT into the blood vessel, cellular degenerative symptoms including vacuolation and cell fragmentation, and nuclear DNA strand cleavage as detected by TUNEL staining. The preventive effects on I/R injuries were in the order: Asc2G > Asc2P >> Asc. This order of preventive degrees of three anti-oxidants is partly attributable to proper efficiency of conversion to vitamin C and stability in blood stream; Asc2P was moderately converted to a free monoanion form of Asc in human serum, but, in rat serum, so efficiently converted to Asc as to undergo the resultant oxidative decomposition before reaching the liver, whereas Asc2G underwent scarce conversion to Asc in human serum but moderate conversion in rat serum, suggesting that Asc2P might be less cytoprotective against I/R injury than Asc2G in the rat liver in a way different from the human liver. In contrast Asc was so susceptible to autooxidation as to be rapidly decomposed in either rat or human serum. The concentrations of ascorbyl radicals (AscR) in serum were unchanged during I/R for sham-operated rats, but appreciably diminished time-dependently for I/R-operated rats as shown by ESR spectra. A marked increase in serum AscR occurred in rats receiving Asc, Asc2G or Asc2P, but it was time-dependently restored down to the pre-ischemic level of AscR in I/R-operated rats more rapidly than in sham-operated rats. Thus, hepatic I/R injuries were shown to be prevented more markedly by Asc2G or Asc2P than by Asc, which is attributable to efficiencies of both vitamin C conversion and subsequent AscR retention. 相似文献
88.
89.
90.
Seema Jilani 《Saudi Journal of Biological Sciences》2013,20(3):257-264
In Pakistan, to increase agricultural production, higher amounts of fertilizers and pesticides are being used. The residues of the applied pesticides stay in the environment and therefore causing contamination of air, water and land. Moreover, agricultural industries are also contributing relatively high quantities of toxic pesticides into the environment. Since most of them have no treatment facilities. These pesticides may be toxic, mutagenic or carcinogenic. They may be bioaccumulated or biomagnified by the biota. Therefore its removal from environmental systems needs special attention. In this study, bacterial isolate, Pseudomonas, designated as IES-Ps-1, was used to assess its potential for pesticide removal from industrial wastewater using the biosimulator (activated sludge process). During experimental studies conducted in the flask as well as in biosimulator, it was observed that IES-Ps-1 grows normally at low concentrations of added insecticides when compared with the control test (without pesticide). However, at high concentrations the microbial count decreased but no death occurred and the culture remained in lag phase. In many cases, the growth of organisms in the presence of the particular substrate serves as an indication about its metabolic potential. However, to confirm these results, chemical oxygen demand (COD) and HPLC analysis were performed. Under aerobic culture conditions using mechanical aerators in biosimulator, almost complete removal of Cypermethrin at 20 mg/L dose occurred during 48 h. The study findings indicate that IES-Ps-1 strain, can be used for the treatment of the pesticide contaminated environment. Such study may be valuable to scientist and engineers, who are trying to develop methods for the treatment of toxic organic waste using the biological treatment process. 相似文献