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1.
Locally perceiving hard global constraints in multi-agent scheduling   总被引:2,自引:0,他引:2  
We propose how to model enterprise facilities (like factories, warehouses, etc.) in a multi-product production/distribution network, capacity management at those facilities, and scheduling agents which act as enterprise managers, taking decisions that affect the available capacity. A coordination mechanism through which scheduling agents can locally perceive hard global temporal constraints is also proposed.  相似文献   
2.
The adipose fin is small, nonpared, and usually located medially between the dorsal and caudal fin. Its taxonomic occurrence is very restrict; thus, it represents an important trace for taxon distinction. As it does not play a known vital physiological roll and it is easily removed, it is commonly used in marking and recapture studies. The present study characterizes the adipose fin of Prochilodus lineatus, as it is poorly explored by the literature. The adipose fin consists basically of a loose connective core, covered by a stratified epithelium supported by collagen fibers. At the epithelium, pigmented cells and alarm substance cells are found. Despite the name, adipocytes or lipid droplets are not observed on the structure of the fin.  相似文献   
3.
Abstract: This paper proposes a method to enzymatically treat poor‐quality cocoa almonds (known as “slate”) to ensure the formation of chocolate flavor precursors. The production of flavor precursors improves the quality of these almonds, which are usually responsible for the low quality of the liquor produced. Proteases and carboxypeptidases from different sources were tested under various conditions. The different treatments were evaluated by chemical analysis (hydrolysis efficiency) and sensory analysis of the treated material compared to good‐quality cocoa almonds. The results show that it is possible, through the use of microbial enzymes, to generate the mixture of compounds that will release, after roasting, the characteristic chocolate flavor in poor‐quality almonds. However, it is necessary to optimize the conditions of enzymatic treatment to obtain better results and thus establish a process that can be used for industrial purposes for manufacturing cocoa and chocolate. Practical Application: The basidiomycete Moniliophtora perniciosa is the causative agent of witches’ broom disease (WBD) of the cocoa tree, whose seeds are the source of chocolate. It is the most important phytopathological problem of cocoa‐producing areas of the American continent, and has decimated the Brazilian cocoa industry. In Bahia (Brazil), M. perniciosa was identified in 1989 and, as a consequence of its spreading, the annual production of cocoa almonds dropped from 450000 to 90000 tons within 12 y, reducing export values from an all‐time high of about US$ 1 billion to 110 million. The high incidence of WBD incapacitates Brazil to produce enough cocoa almonds even for the internal market, leading the country to import low‐quality cocoa almonds mainly from African countries. Our work proposes an enzymatic treatment to increase the quality of that cocoa almonds and, consequently, to improve the quality of the chocolate produced and consumed in the country.  相似文献   
4.
Fretting corrosion damages are commonly observed when two metallic bodies, which are in contact with each other, are subjected to oscillatory motions of low amplitude. Such kind of degradation mode is often responsible for limited durability of aeronautical joints. In the present paper, a multifunctional duplex coating based on Si–C–N and diamond-like carbon (DLC) materials, combining corrosion resistance and good tribological properties is described. Amorphous hydrogenated SiC, SiCN, SiC/DLC and SiCN/DLC were deposited on steel substrates by a plasma assisted chemical vapour deposition (PACVD) technique, using tetramethylsilane (TMS), ammonia (NH3) or acetylene (C2H2) as gas precursors. Nitrogen incorporation has shown to improve the corrosion protection ability of SiC coatings. The corrosion behaviour and the tribological performance in aqueous media of SiCN/DLC coating have therefore been investigated. A test rig has been designed to validate the fretting resistance of this duplex coating for aeronautic applications. It was found that the combination of a SiCN-based PACVD sublayer with a DLC topcoat could provide an enhanced solution to withstand both fretting and corrosion.  相似文献   
5.
Planar electrochemical microcells were micromachined in a microcrystalline boron-doped diamond (BDD) thin layer using a femtosecond laser. The electrochemical performances of the new laser-machined BDD microcell were assessed by differential pulse anodic stripping voltammetry (DPASV) determinations, at the nanomolar level, of the four heavy metal ions of the European Water Framework Directive (WFD): Cd(II), Ni(II), Pb(II), Hg(II). The results are compared with those of previously published BDD electrodes. The calculated detection limits are 0.4, 6.8, 5.5, and 2.3 nM, and the linearities go up to 35, 97, 48, and 5 nM for, respectively, Cd(II), Ni(II) Pb(II), and Hg(II). The detection limits meet with the environmental quality standard of the WFD for three of the four metals. It was shown that the four heavy metals could be detected simultaneously in the concentration ratio usually measured in sewage or runoff waters.  相似文献   
6.
This prospective observational study aimed at evaluating efficacy and biocompatibility performances of the new heparin-coated Evodial dialyzers with/without systemic heparin reduction. After a 4-week wash-out period with reference polysulfone F70S dialyzers, 6 hemodialysis patients were sequentially dialyzed with Evodial, F70S, and Evodial dialyzers using 30% heparin reduction, each period of treatment was 4 weeks. Removal rates (RR) (urea, creatinine, and β2-microglobulin), dialysis dose, and instantaneous clearances (urea and creatinine) were measured as well as inflammatory (C-reactive protein, fibrinogen, interleukin 6, tumor necrosis factor α, and monocyte chemoattractant protein-1) and oxidative stress (OS) (superoxide anion, homocysteine, and isoprostanes) parameters at the end of each study period. Patients treated with Evodial or F70S dialyzers for 4 weeks presented comparable dialysis efficacy parameters including urea and creatinine RR, dialysis dose and instantaneous clearances. By contrast, a significantly lower but reasonably good β2-microglobulin RR was achieved with Evodial dialyzers. Regarding biocompatibility, no significant difference was observed with inflammation and OS except for postdialysis monocyte chemoattractant protein-1 which significantly decreased with Evodial dialyzers. Thirty percent heparinization reduction with Evodial dialyzers did not induce any change in inflammation but led to an improvement in OS as demonstrated by a decrease in postdialysis superoxide production and predialysis homocysteine and isoprostane. This bioactive dialyzer together with heparin dose reduction represents a good trade-off between efficacy and biocompatibility performance (improvement in OS with a weak decrease in efficacy) and its use is encouraging for hemodialysis patients not only in reducing OS but also in improving patient comorbid conditions due to lesser heparin side effects.  相似文献   
7.
8.
The impact of the growth of two Gram-negative bacteria, Psychrobacter celer and Hafnia alvei, inoculated at 102 and 106 cfu/g, on the dynamics of a multispecies community as well as on volatile aroma compound production during cheese ripening was investigated. Results showed that P. celer was able to successfully implant itself in cheese, regardless of its inoculation level. However, when it was inoculated at a high level, the bacterial biodiversity was drastically lowered from day 25 to the end of ripening. Overall, the presence of P. celer led to the higher production of volatile aroma compounds such as aldehydes, ketones and sulfur compounds. Regardless of its inoculation level, H. alvei barely affected the growth of the bacterial community and was subdominant at the end of ripening. It influenced total volatile aroma compound production with volatile sulfur compounds being the most abundant. Overall, these two bacteria were able to implant themselves in a cheese community and significantly contributed to the aromatic properties of the cheese. Their role in flavoring and their interactions with the technological microorganisms must be considered during cheese ripening and should be further investigated.  相似文献   
9.
High prevalence of hyperhomocysteinemia is common in hemodialysis (HD) patients and could contribute to worsen the cardiovascular risk. Beyond vitamin B status, dialysis modality itself could influence homocysteine (Hcy) levels. The objective was compare the reduction rate (RR) of Hcy and cysteine in stable dialyzed patients treated by standard HD or hemodiafiltration (HDF). Seventy‐five patients undergoing stable dialysis through standard high‐flux HD (n = 35) or HDF (n = 40) were included. Biological parameters were determined before and after a midweek dialysis session. Urea percent reduction per session and Kt/V index (K, body urea clearance, T, time of dialysis, and V, urea distribution volume), defined as a marker of dialysis efficacy, were similar between HD and HDF groups. By contrast, higher RR of beta2 microglobulin (β2m) was observed in HDF compared with HD (78.6 vs. 72.0%, respectively; P < 0.001). Likewise, higher RR of Hcy was obtained with HDF compared to HD (46.0 vs. 41.5%, respectively; P < 0.05), whereas the RR of cysteine was similar in both groups. Interestingly, a positive correlation between Hcy RR and urea Kt/V index was observed (r = 0.29, P < 0.05) and between Hcy RR and β2m RR (r = 0.45, P < 0.001). Time‐averaged concentration (TAC) of Hcy was lower with HDF compared with HD (17.8 vs. 19.1 μmol/L, respectively), although not significant. There was no difference in median Hcy according to dialysis modality for neither pre‐ nor postdialysis levels. Significant higher removal of Hcy was observed with HDF compared with standard HD, although urea Kt/V index was similar. Enhanced removal of middle molecules, such as β2m, could be involved in Hcy RR improvement with HDF.  相似文献   
10.
Lebret B  Guillard AS 《Meat science》2005,70(2):247-257
The objective of this study was to provide some information on the influence of outdoor rearing on pasture (O) compared with indoor (I) on carcass and meat quality of cull sows. Twelve sows (6 per group) originating from the same breeding unit were slaughtered 11 days after their last weaning. O sows had heavier and fatter carcasses, however lipid content in Longissimus (L) and Triceps brachii (TB) muscles was not affected. Grazing of O sows led to a high increase in the n  3 fatty acid content, particularly the C18:3 linolenic acid in the backfat and L muscle, thus improving the meat nutritional quality. Vitamin E content appeared (P = 0.13) to be increased in the backfat of O sows, but not in the muscles. Lipid oxidation in meat during storage was similar between groups. Histological and metabolic observations showed that outdoor rearing increased the glycolytic capacity of the L muscle, and the oxidative capacity of the TB. Outdoor rearing did not influence meat pH1 and pHu, but decreased colour (a1 and b1 values) of the TB, and increased the processing yield of loin into cured bacon. Outdoor rearing decreased the red colour intensity and homogeneity, but improved tenderness of cured loins.  相似文献   
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