近年来国内外玻璃钢工业发展概况

本文综述了国内外玻璃钢/复合材料工业发展现状,分析了我国玻璃钢/复合材料工业存在的一些问题,指出应该重视市场开发,提高产品质量,文章展望了我国玻璃钢/复合材料发展前景。     

Evaluation of rapid methods for in-situ characterization of organic contaminant load and biodegradation rates in winery wastewater.

Rapid methods for the in-situ evaluation of the organic load have recently been developed and successfully implemented in municipal wastewater treatment systems. Their direct application to winery wastewater treatment is questionable due to substantial differences between municipal and winery wastewater. We critically evaluate the use of UV-VIS spectrometry, buffer capacity testing (BCT), and respirometry as rapid methods to determine organic load and biodegradation rates of winery wastewater. We tested three types of samples: actual and treated winery wastewater, synthetic winery wastewater, and samples from a biological batch reactor. Not surprisingly, respirometry gave a good estimation of biodegradation rates for substrate of different complexities, whereas UV-VIS and BCT did not provide a quantitative measure of the easily degradable sugars and ethanol, typically the main components of the COD in the influent. However, our results strongly suggest that UV-VIS and BCT can be used to identify and estimate the concentration of complex substrates in the influent and soluble microbial products (SMP) in biological reactors and their effluent. Furthermore, the integration of UV-VIS spectrometry, BCT, and mathematical modeling was able to differentiate between the two components of SMPs: substrate utilization associated products (UAP) and biomass associated products (BAP). Since the effluent COD in biologically treated wastewaters is composed primarily by SMPs, the quantitative information given by these techniques may be used for plant control and optimization.     

Interaction Between Phenolic Compounds and Lipase: The Influence of Solubility and Presence of Particles in the IC50 Value

Obesity is one of the principal human health problems and one of the main treatments against it is the inhibition of pancreatic lipase, the main responsible enzyme of lipid digestion. For that purpose, previous studies have tested several phenolic compounds against lipase, without considering their aggregation behavior in aqueous solutions. Because of this, the present study focuses on understanding how the solubility and the presence of particles affect the IC₅₀ value of the interaction between lipase and phenolic compounds present in beverages like fruit juices and teas. Therefore, the inhibitory capacity against pancreatic lipase and the aggregate formation of 9 phenolic compounds (quercetin, rutin, myricetin, catechin, epigallocatechin gallate, cyanidin, caffeic acid, chlorogenic acid, and vanillic acid) were analyzed. The results obtained together with the solubility data from literature were treated by principal component analysis and indicate that the IC₅₀ value does not correlate with the solubility or aggregate formation of the phenolic compounds. However, the IC₅₀ values of phenolic compounds which aggregate during the assay conditions have low reproducibility. This study shows that the aggregate formation of phenolic compounds plays an important role during in vitro assays for pancreatic lipase inhibition and should be considered in future experiments as it can lead to false positive results. In terms of particle formation, the flavonoids investigated in this study are more prone to aggregation compared to the phenolic acids.     

Seismic response of a free standing fuel rack construction to 3-D floor motion

Seismic analysis of free standing submerged racks is complicated by the presence of water and structural non-linearities such as fuel assembly cell impact and floor interface friction. A direct time integration technique has been proposed to analyze this class of structures. Application of the time integration technique on a fourteen degree of freedom lumped mass model of the rack reveals some heretofore unpublished quirks in the structure's behavior. The method of analysis is utilized to compare the seismic response of some representative rack designs. Results show wide differences in the structural response, depending on the fabrication details of racks.     

Communications technology and the public sector: Understanding the process of adoption

The introduction of technological innovation in the public service sector is typically greeted with enthusiasm. The implementation and subsequent adoption, however, has not come easily or quickly. Few people argue the potential and value of technology anymore; the issues that inhibit adoption of technology are essentially economic and political. The need to better understand the process of adoption and the factors that contribute to its implementation in the public service sector are the basis of this article.     

Effects of sleep loss on team decision making: motivational loss or motivational gain?

OBJECTIVE: To examine the effects of 30 hr of sleep loss and continuous cognitive work on performance in a distributed team decision-making environment. BACKGROUND: To date, only a few studies have examined the effect of sleep loss on distributed team performance, and only one other to our knowledge has examined the relationship between sleep loss and social-motivational aspects of teams (Hoeksema-van Orden, Gaillard, & Buunk, 1998). METHOD: Sixteen teams participated; each comprised 4 members. Three team members made threat assessments on a military surveillance task and then forwarded their judgments electronically to a team leader, who made a final assessment on behalf of the team. RESULTS: Sleep loss had an antagonistic effect on team decision-making accuracy and decision time. However, the performance loss associated with fatigue attributable to sleep loss was mediated by being part of a team, as compared with performing the same task individually - that is, we found evidence of a "motivational gain" effect in these sleepy teams. We compare these results with those of Hoeksema-van Orden et al. (1998), who found clear evidence of a "social loafing" effect in sleepy teams. CONCLUSION: The divergent results are discussed in the context of the collective effort model (Karau & Williams, 1993) and are attributable in part to a difference between independent and interdependent team tasks. APPLICATION: The issues and findings have implications for a wide range of distributed, collaborative work environments, such as military network-enabled operations.     

Presence, processing, and localization of mouse ADAM15 during sperm maturation and the role of its disintegrin domain during sperm-egg binding

Successful fertilization requires gametes to complete several stages, beginning with maturation and transport along the male and female reproductive tracts and ending with the interaction between the sperm and the egg. This last step involves sperm-egg adhesion and membrane fusion. ADAMs (disintegrin and metalloprotease domain proteins) are a family of membrane-anchored glycoproteins that are thought to play diverse roles in cell-cell adhesion through their interaction with integrins. This study analyzes the presence, location, processing, and possible role of ADAM15 in mouse sperm. The presence of ADAM15 in mouse spermatozoa was detected by Western blotting, which revealed that ADAM15 is post-translationally processed, during epididymal sperm maturation and the acrosome reaction. The 35 kDa antigen present in the acrosome-reacted sperm is the last proteolytic product of the 110/75 kDa ADAM15 found in non-capacitated sperm. This 35 kDa protein contains the disintegrin domain. By indirect immunofluorescence, ADAM15 was identified in the acrosomal region and along the flagellum of mouse spermatozoa. In acrosome-reacted sperm, ADAM15 was lost from the acrosomal region, but remained diffusely distributed throughout the head and flagellum. Furthermore, the ADAM15 disintegrin domain (RPPTDDCDLPEF) partially inhibited fusion and almost completely inhibited sperm-oolemma adhesion. In conclusion, our data indicate that ADAM15 is present in the testis and in spermatozoa from the caput, corpus, and cauda epididymis, as well as in non-capacitated and acrosome-reacted gametes. Results also indicate that ADAM15 is processed during epididymal maturation and acrosome reaction and that it may play a role during sperm-egg binding.