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1.
Industrial sectors that operate in uncertain environments - with demand variability, product seasonality and different industrialisation structures - need studies that enable identification and forecast trends. Therefore, the development of competitiveness extends beyond a company’s individual performance. Collective action, whether toward consumer markets, supplier markets, competitors and substitutes, can reinforce or help reformulate the current practices of an organisation, besides providing better results in the development of strategies and competitive positioning. Thus, clothing, the sector addressed in this work, is characterised by a long, fragmented, heterogeneous production chain, the competitiveness of which is linked to product differentiation. Therefore, the use of systemic approaches to study this sector is effective. In this sense, this research aims at adapting Systems Thinking and Scenario Planning (STSP) so that it supports the development and planning process in a given sector. Thus, this research applies STSP adapted to an analysis of the clothing sector in the northern region of Rio Grande do Sul State, Brazil. As a result, in academic terms, this research proposed and validated a method for analysing industrial sectors of the clothing industry. In the sectoral context, this research identified elements that leverage the sector’s competitiveness, besides generating knowledge and learning aimed at strengthening the sectoral structure identified, and fostering the formation of a new clothing cluster.  相似文献   
2.
Rapid renewal of auditory hair bundles   总被引:14,自引:0,他引:14  
Stereocilia, also known as hair bundles, are mechanosensitive organelles of the sensory hair cells of the inner ear that can detect displacements on a nanometre scale and are supported by a rigid, dense core of actin filaments. Here we show that these actin-filament arrays are continuously remodelled by the addition of actin monomers to the stereocilium tips, and that the entire core of the stereocilium is renewed every 48 hours. This unexpected dynamic feature of stereocilia will help our understanding of how auditory sensory function develops and is maintained.  相似文献   
3.
Summary Wild-type strains and auxotrophic mutants ofAspergillus flavus, differing regarding aflatoxin production, were tested for esterases isozymes. Esterases variation was found in all strains used, and a possible correlation between the pattern of esterase bands and aflatoxin production is suggested.Acknowledgment. The authors are thankful to the National Council for the development of Science and Technology (CNPq) and Assistance to Research for São Paulo State (FAPESP) for financial assistance.  相似文献   
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Summary 11 wild-type strains ofMetarrhizium anisopliae were electrophoretically tested for phosphatases and esterases. Phosphatase was homogeneous for all strains. For esterase it was possible to distinguish 5 different patterns with which it is possible to characterize the strains analyzed.Acknowledgment. The authors are thankful to the Conselho Nacional de Desenvolvimento Cientifico e Tecnológico (CNPq) and to the Empresa Brasileira de Pesquisa Agropecuária (EM-BRAPA) for financial assistance.  相似文献   
6.
Azevedo RB  Lohaus R  Srinivasan S  Dang KK  Burch CL 《Nature》2006,440(7080):87-90
The mutational deterministic hypothesis for the origin and maintenance of sexual reproduction posits that sex enhances the ability of natural selection to purge deleterious mutations after recombination brings them together into single genomes. This explanation requires negative epistasis, a type of genetic interaction where mutations are more harmful in combination than expected from their separate effects. The conceptual appeal of the mutational deterministic hypothesis has been offset by our inability to identify the mechanistic and evolutionary bases of negative epistasis. Here we show that negative epistasis can evolve as a consequence of sexual reproduction itself. Using an artificial gene network model, we find that recombination between gene networks imposes selection for genetic robustness, and that negative epistasis evolves as a by-product of this selection. Our results suggest that sexual reproduction selects for conditions that favour its own maintenance, a case of evolution forging its own path.  相似文献   
7.
Holepyris semiruber Kieffer is redescribed and illustrated based on freshly collected specimens. Holepyris semiruber var. striatipleura Kieffer is considered a colour variant of this species and therefore a junior synonym of H. semiruber syn. nov. This species is transferred to Disepyris, D. semiruber (Kieffer) comb. nov., based on the possession of a short 2r-rs&Rs vein in the fore wing and presence of long flat spine-shaped setae on the outer (posterior) surface of the protarsi. The male is described for the first time from new specimens collected in South Africa. This species is recorded for the first time from Namibia and Zimbabwe. All photographs are available on www.waspweb.org.  相似文献   
8.
We present the fabrication and testing of a silicon carbide(SiC)balanced mass double-ended tuning fork that survives harsh environments without compromising the device strain sensitivity and resolution bandwidth.The device features a material stack that survives corrosive environments and enables high-temperature operation.To perform high-temperature testing,a specialized setup was constructed that allows the tuning fork to be characterized using traditional silicon electronics.The tuning fork has been operated at 600 ℃ in the presence of dry steam for short durations.This tuning fork has also been tested to 64 000 G using a hard-launch,soft-catch shock implemented with a light gas gun.However,the device still has a strain sensitivity of 66 Hz/με and strain resolution of 0.045 με in a 10 kHz bandwidth.As such,this balanced-mass double-ended tuning fork can be used to create a variety of different sensors including strain gauges,accelerometers,gyroscopes,and pressure transducers.Given the adaptable fabrication process flow,this device could be useful to micro-electro-mechanical systems(MEMS) designers creating sensors for a variety of different applications.  相似文献   
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The growth of the petrochemical industry is based on end-user applications such as the automotive and construction sectors, which are the main drivers of the styrene market. However, the use of substitutes for petrochemicals is a reality and creates a competition in the applications of petroleum products. In this sense, this research aimed to design a system dynamics model to evaluate different scenarios, observing the behavior of the styrene demand over time. In the first phase of the project, a greater understanding of the issue was created and a closed loops diagram was elaborated. It was used during the second phase to design an explanatory regression validation model for the styrene demand. In phase three, a visualizing model and scenarios were designed. The scenarios themselves and the results of each scenario were evaluated. The designed and simulated scenarios aimed to evaluate the impact that the use of substitute materials and the variations in gross domestic product cause to the styrene market. The use of system dynamics together with scenario planning was efficient as different strategies for the market could be evaluated based on the simulated scenarios. A critical analysis of the model’s contribution to the decision-making within organizations concludes the study.  相似文献   
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