以太网收发器不断增加端口数量以提高网络利用率

以太网已成为最常用的企业通信标准之一.随着大多数企业从传统信息系统转移到基于网络的应用,各企业网络中的带宽利用率在大幅提高.     

Barriers,biases, and beliefs about arteriovenous fistula placement in children: A survey of the International Pediatric Fistula First Initiative (IPFFI) within the Midwest Pediatric Nephrology Consortium (MWPNC)

There has been recent emphasis on increased arteriovenous fistula (AVF) use and decreased central venous catheter use in hemodialysis (HD) patients. The International Pediatric Fistula First Initiative was founded via collaborative effort with the Midwest Pediatric Nephrology Consortium to alert nephrologists, surgeons, and dialysis staff to consider fistulae as the best access in pediatric HD patients. A multidisciplinary educational DVD outlining expectations and strategies to increase AVF placement and usage in children was created. Participants were administered a survey previewing and postviewing to identify barriers to placement and usage of AVF in children. A total of 52 surveys were subdivided as either “dialysis staff” or “proceduralist” at five centers. Thirty‐three percent of respondents were unaware if their practice was following published guidelines. Sixty‐five percent of respondents stated they referred to a dedicated vascular access surgeon at their respective institutions. Methods used to monitor AVF function included physical exam, venous pressure monitoring, and ultrasound dilution. Vascular access was placed within 3 months in only 35% of patients. Interdisciplinary communication problems between surgeons, interventional radiologists, and nephrologists were identified as a major barrier. Lack of AVF usage was often due to maturation failure. Routine access rounds did not occur in any centers. Regarding monitoring, 74% of the respondents use physical exam, 26% use venous pressure monitoring, and 9% use ultrasound dilution. Ninety‐three percent of dialysis staff stated they would change practice patterns following the intervention; however, 12% of surgeons stated they would alter practice patterns. To our knowledge, this is the first report to identify barriers to placement of AVF in children from the perspectives of multidisciplinary team members including pediatric nephrologists, surgeons, interventional radiologists, and multidisciplinary dialysis staff.     

Isolation of Salmonella typhimurium from outbreak-associated cake mix

During May and June of 2005, 26 persons in several states were infected by a single strain (isolates indistinguishable by pulsed-field gel electrophoresis) of Salmonella enterica serotype Typhimurium after eating cake batter ice cream. The cake mix used to prepare the cake batter in the ice cream was implicated by epidemiologic investigation as the source of Salmonella contamination. Initial tests did not detect Salmonella in cake mix collected during the outbreak investigation. The objective of this study was to evaluate different procedures to isolate Salmonella from the implicated cake mix, cake, and ice cream. All outbreak-associated food samples (14 samples) were collected during the outbreak investigation by health departments of several of the states involved. Different combinations of Salmonella isolation procedures, including sample size, preenrichment broth, enrichment broth, enrichment temperature, and isolation medium, were used. Salmonella Typhimurium was isolated from two cake mix samples; the food isolates were indistinguishable from the outbreak pattern by pulsed-field gel electrophoresis subtyping. Universal preenrichment broth was substantially better than was lactose broth for preenrichment, and tetrathionate broth was better than was Rappaport-Vassiliadis broth for isolating Salmonella from the two positive cake mix samples. Although more typical Salmonella colonies were observed on plates from enrichment cultures grown at 35 degrees C, more confirmed Salmonella isolates were obtained from plates of enrichment cultures grown at 42 degrees C. Brilliant green agar, xylose lysine tergitol 4 agar, xylose lysine desoxycholate agar, Hektoen enteric agar, and bismuth sulfite agar plates were equally effective in isolating Salmonella from cake mix. The best combination of preenrichment-enrichment conditions for isolating the outbreak strain of Salmonella was preenrichment of cake mix samples in universal preenrichment broth at 35 degrees C for 24 h, followed by enrichment in tetrathionate broth at 42 degrees C for 24 h.     

Expression of prolactin-related protein I at the fetomaternal interface during the implantation period in cows

The bovine placenta secretes multiple molecules during implantation and placentation, many of which are produced by binucleate cells. In this study, production of prolactin-related protein I (PRP-I), a member of the non-classical prolactin-related family, was investigated during the implantation period in cows. Expression of bovine PRP-I (bPRP-I) in the placentome was examined during the preimplantation (days 17-19), implantation (days 20-25) and post-implantation (days 30-60) periods by immunohistochemistry, immunofluorescence and in situ hybridization. During the preimplantation period, both bPRP-I and bovine placental lactogen (bPL) were undetectable in trophoblastic cells. Both bPRP-I mRNA and protein appeared first at day 20 of gestation in trophoblastic binucleate cells and multinuclear cells that might migrate into the endometrium and fuse to epithelium; however, no bPL was detected in binucleate cells at this time. After implantation, on day 30, both bPRP-I and bPL were detected in binucleate cells and were co-expressed in the same cells. These data indicate that bPRP-I may play a role before implantation and that bPRP-I may be an excellent marker for trophoblastic cell differentiation, as well as a candidate for pregnancy diagnosis.     

Adding apples and oranges: The monitoring of energy efficiency in the Dutch food industry

This article develops indicators to monitor energy efficiency developments in the food and tobacco industry based on physical production data at the firm level provided by the statistics office of the Netherlands in a confidential basis. We measure energy efficiency by using an energy efficiency indicator which is the aggregate specific energy consumption. Our results show that the food and tobacco industry has improved their energy efficiency indicator in primary terms by about 1% per year (uncertainty range between 0.9 and 1.3). In terms of final energy, there has been a decrease on the indicator for final demand of fuels of about 1.8% p.a. while there has been no improvement in the indicator for final demand of electricity. The development in energy efficiency is coherent with the reported implementation rate of energy conservation projects. We conclude that the type and the quality of the data compiled by Statistics Netherlands for the food sector is sufficient to develop indicators as required by energy and climate policy.     

Optimisation of sweetener and bulking agent levels for the preparation of functional Chhana‐murki

A functional Chhana‐murki (FCM) was formulated at laboratory scale using different levels of microcrystalline cellulose (MCC): inulin (fibre) blend (1:1), isomalt:lactitol (polyol) blend (1:1), gum arabic and sucralose by response surface methodology (RSM) and sensory analysis. The colour and appearance, texture, flavour and overall acceptability scores increased by increasing the fibre level from 5 to 10% (w/w) and polyol level from 5 to 15% (w/w). The sweetness score increased significantly by increasing the sucralose level from 600 to 800 ppm (w/w). The optimised product had 738 ppm sucralose, 10% fibre, 15% polyol and 1.1% gum arabic.     

Effect of modified atmosphere packaging on the persistence and expression of virulence factors of Escherichia coli O157:H7 on shredded iceberg lettuce

Fresh-cut leafy greens contaminated with Escherichia coli O157:H7 have caused foodborne outbreaks. Packaging conditions, coupled with abusive storage temperatures of contaminated lettuce, were evaluated for their effect on the potential virulence of E. coli O157:H7. Shredded lettuce was inoculated with 5.58 and 3.98 log CFU E. coli O157:H7 per g and stored at 4 and 15°C, respectively, for up to 10 days. Lettuce was packaged under treatment A (modified atmosphere packaging conditions used for commercial fresh-cut produce, in gas-permeable film with N(2)), treatment B (near-ambient air atmospheric conditions in a gas-permeable film with microperforations), and treatment C (high-CO(2) and low-O(2) conditions in a gas-impermeable film). E. coli O157:H7 populations from each treatment were determined by enumeration of numbers on MacConkey agar containing nalidixic acid. RNA was extracted from packaged lettuce for analysis of expression of virulence factor genes stx(2), eae, ehxA, iha, and rfbE. E. coli O157:H7 populations on lettuce at 4°C under all treatments decreased, but most considerably so under treatment B over 10 days. At 15°C, E. coli O157:H7 populations increased by at least 2.76 log CFU/g under all treatments. At 15°C, expression of eae and iha was significantly greater under treatment B than it was under treatments A and C on day 3. Similarly, treatment B promoted significantly higher expression of stx(2), eae, ehxA, and rfbE genes on day 10, compared with treatments A and C at 15°C. Results indicate that storage under near-ambient air atmospheric conditions can promote higher expression levels of O157 virulence factors on lettuce, and could affect the severity of E. coli O157:H7 infections associated with leafy greens.     

The growth and morphology of core/shell heterostructured conical carbon fibers

Core/shell heterostructured conical carbon fibers with silicon-based cores and graphitic carbon sheaths have been grown on silicon carbide (SiC) surfaces exposed to the combustion of methane. The conical carbon fibers (CCFs), which taper from a circular base to a point, appear to form by two simultaneous growth processes, axial tip-growth and radial fiber thickening. Radial fiber thickening results from pyrolytic carbon deposition from gas-phase hydrocarbons. Oxidation of SiC surfaces is proposed to produce gas-phase silicon oxides, which feed axial tip-growth and install the silicon-based core. The unusual morphology of the CCFs, including bending, branching, curving and tapering, is proposed to result from the action and interplay of these two simultaneous processes.     

Infilled Reinforced Concrete Beams for Sustainable Construction

This paper presents a study carried out on infilled reinforced concrete beams for sustainable construction. In reinforced concrete beams, less stressed concrete below neutral axis can be replaced by some light weight material to reduce the weight of the structure and also achieve the economy. The used infilled material is brick. Sustainability can be achieved by replacing the partially used concrete. By saving concrete, the authors save cement, which reduces the green house gases emissions. So it is considered as environment friendly. Since infilled beam acts like a layered member, there needs a theory to analyze it. Method of initial functions is used for the analysis of the infilled RC （reinforced concrete） beams. This method is successfully applied on infilled beam. Results show that physical conditions are verified for infilled beam.