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31.
Weller SC 《Textile rental》1992,75(10):56, 58-56, 62
A potential $177 million-a-year market has been opened to textile rental operators, thanks to OSHA's recent ruling on bloodborne pathogens. Healthcare providers nationwide are now searching for solutions to their protective apparel needs. Such customer needs are what drive niche markets. Whether you've been serving the healthcare market for years or are just now targeting it, here are the marketing strategies you need. 相似文献
32.
Weller SC 《Textile rental》1992,76(1):44, 46
The last phase of the federal OSHA standard on occupational exposure to bloodborne pathogens became effective July 6. However, compliance deadlines may vary in the 23 states and two U.S. territories that have their own OSHA offices. The states and territories have the option of adopting the federal standard or drafting their own plans. Here's a status report on the OSHA-approved state programs for bloodborne pathogens. 相似文献
33.
Weller SC 《Textile rental》1991,75(3):32-33
Textile rental companies are poised on the edge of a boom in the healthcare marketplace. The detonator is outpatient care. Between 1984 and 1990, outpatient visits increased from almost 233 million to more than 310 million, or about 33 percent. The shift from traditional hospital care to outpatient or ambulatory service is creating a new market opportunity for textile rental services. Innovative medical services are cropping up in suburban malls and neighborhoods, and demand is high for high-quality linen supply or contract laundry services. 相似文献
34.
Kirk Weller Ilana Arnon Ed Dubinsky 《Canadian Journal of Science, Mathematics, & Technology Education》2013,13(2):129-159
Abstract In an earlier study of preservice elementary and middle school teachers’ beliefs about repeating decimals, Weller, Arnon, and Dubinsky (2009) reported on a comparison of the mathematical performance of 77 preservice teachers who completed an APOS-based instructional unit with 127 preservice teachers who completed traditional instruction. The purpose of the current study, based on 47 interviews conducted 4 months after the instruction, during which time there was no further instruction on this topic, is to determine the strength and stability (over time) of the students’ beliefs, to uncover thinking that did not arise in the earlier study, and to see whether the interviews yield similar comparative results. The interviews did uncover changes in student thinking. The students who received the APOS-based instruction developed stronger and more stable (over time) beliefs that a repeating decimal is a number; a repeating decimal has a fraction or integer to which it corresponds; a repeating decimal in general equals its corresponding fraction or integer; and, in particular, In addition, a number of indices and categories were developed that may prove useful in other studies consisting of the comparison of interview and questionnaire data involving a large number of interview subjects. 相似文献
35.
Herpes simplex virus type 1 (HSV-1) DNA replication intermediates exist in a complex nonlinear structure that does not migrate into a pulsed-field gel. Genetic evidence suggests that the product of the UL12 gene, termed alkaline nuclease, plays a role in processing replication intermediates (R. Martinez, R. T. Sarisky, P. C. Weber, and S. K. Weller, J. Virol. 70:2075-2085, 1996). In this study we have tested the hypothesis that alkaline nuclease acts as a structure-specific resolvase. Cruciform structures generated with oligonucleotides were treated with purified alkaline nuclease; however, instead of being resolved into linear duplexes as would be expected of a resolvase activity, the artificial cruciforms were degraded. DNA replication intermediates were isolated from the well of a pulsed-field gel ("well DNA") and treated with purified HSV-1 alkaline nuclease. Although alkaline nuclease can degrade virion DNA to completion, digestion of well DNA results in a smaller-than-unit-length product that migrates as a heterogeneous smear; this product is resistant to further digestion by alkaline nuclease. The smaller-than-unit-length products are representative of the entire HSV genome, indicating that alkaline nuclease is not inhibited at specific sequences. To further probe the structure of replicating DNA, well DNA was treated with various known nucleases; our results indicate that replicating DNA apparently contains no accessible double-stranded ends but does contain nicks and gaps. Our data suggest that UL12 functions at nicks and gaps in replicating DNA to correctly repair or process the replicating genome into a form suitable for encapsidation. 相似文献
36.
A Kassam JW Overstreet C Snow-Harter MJ De Souza EB Gold BL Lasley 《Canadian Metallurgical Quarterly》1996,104(4):408-413
The sensitivity and specificity of a urinary pregnanediol-3-glucuronide (PdG) ratio algorithm to identify anovulatory cycles was studied prospectively in two independent populations of women. Urinary hormone data from the first group was used to develop the algorithm, and data from the second group was used for its validation. PdG ratios were calculated by a cycles method in which daily PdG concentrations indexed by creatinine (CR) from cycle day 11 onward were divided by a baseline PdG (average PdG/Cr concentration for cycle days 6-10). In the interval method, daily PdG/CR concentrations from day 1 onward were divided by baseline PdG (lowest 5-day average of PdG/CR values throughout the collection period). Evaluation of the first study population (n = 6) resulted in cycles with PdG ratios > or = 3 for > or = 3 consecutive days being classified as ovulatory; otherwise they were anovulatory. The sensitivity and specificity of the PdG ratio algorithm to identify anovulatory cycles in the second population were 75% and 89.5%, respectively, for all cycles (n = 88); 50% and 88.3% for first cycles (n = 40) using the cycles method; 75% and 92.2%, respectively, for all cycles (n = 89); and 50% and 94.1% for first cycles (n = 40) using the interval method. The "gold standard" for anovulation was weekly serum samples < or = 2 ng/ml progesterone. The sensitivity values for all cycles and for the first cycle using both methods were underestimated because of apparent misclassification of cycles using serum progesterone due to infrequent blood collection. Blood collection more than once a week would have greatly improved the sensitivity and modestly improved the specificity of the algorithm. The PdG ratio algorithm provides an efficient approach for screening urine samples collected in epidemiologic studies of reproductive health in women. 相似文献
37.
C. J. Greenshields H. G. Weller 《International journal for numerical methods in engineering》2005,64(12):1575-1593
This paper outlines the development of a new procedure for analysing continuum mechanics problems with a particular focus on fluid–structure interaction in flexible tubes. A review of current methods of fluid–structure coupling highlights common limitations of high computational cost and solution instability. It is proposed that these limitations can be overcome by an alternative approach in which both fluid and solid components are solved within a single discretized continuum domain. A single system of momentum and continuity equations is therefore derived that governs both fluids and solids and which are solved with a single mesh using finite volume discretization schemes. The method is validated first by simulating dynamic oscillation of a clamped elastic beam. It is then applied to study the case of interest—wave propagation in highly flexible tubes—in which a predicted wave speed of 8.58 m/s falls within 2% of an approximate analytical solution. The method shows further good agreement with analytical solutions for tubes of increasing rigidity, covering a range of wave speeds from those found in arteries to that in the undisturbed fluid. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
38.
Quorum sensing in Escherichia coli, Salmonella typhimurium, and Vibrio harveyi: a new family of genes responsible for autoinducer production 总被引:1,自引:0,他引:1
In bacteria, the regulation of gene expression in response to changes in cell density is called quorum sensing. Quorum-sensing bacteria produce, release, and respond to hormone-like molecules (autoinducers) that accumulate in the external environment as the cell population grows. In the marine bacterium Vibrio harveyi two parallel quorum-sensing systems exist, and each is composed of a sensor-autoinducer pair. V. harveyi reporter strains capable of detecting only autoinducer 1 (AI-1) or autoinducer 2 (AI-2) have been constructed and used to show that many species of bacteria, including Escherichia coli MG1655, E. coli O157:H7, Salmonella typhimurium 14028, and S. typhimurium LT2 produce autoinducers similar or identical to the V. harveyi system 2 autoinducer AI-2. However, the domesticated laboratory strain E. coli DH5alpha does not produce this signal molecule. Here we report the identification and analysis of the gene responsible for AI-2 production in V. harveyi, S. typhimurium, and E. coli. The genes, which we have named luxSV.h., luxSS.t., and luxSE.c. respectively, are highly homologous to one another but not to any other identified gene. E. coli DH5alpha can be complemented to AI-2 production by the introduction of the luxS gene from V. harveyi or E. coli O157:H7. Analysis of the E. coli DH5alpha luxSE.c. gene shows that it contains a frameshift mutation resulting in premature truncation of the LuxSE.c. protein. Our results indicate that the luxS genes define a new family of autoinducer-production genes. 相似文献
39.
Ultra‐fast thermal annealing of thin films with annealing times of few milliseconds are faster und more energy efficient than conventional furnace annealing methods. By using flash lamp annealing, only the surface is heated while the substrate remains cold. This allows the refinement of indium‐tin‐oxide films on rigid and ultra‐thin flexible glass and improves their conductivity and transmittance. 相似文献
40.
J I Weller 《Journal of dairy science》1988,71(7):1873-1879
Mixed model equations are constructed using the convention of regression on dummy variables that are given values of either unity (presence of the effect) or zero (absence of the effect). In the proposed method, incomplete records were included by computing regression coefficients of sire effects as the regression of the effect on the partial record on the same effect on the complete record. Partial and complete records were treated equally for other effects. Regression and the error components of variance were estimated as simple functions of the length of the partial records. The only additional computation required in sire evaluation was the differential weighting of records in the construction of the mixed model equations. This method was tested on field data and was slightly more accurate than evaluations including partial records without differential weighting and significantly more accurate than evaluations obtained with partial records deleted. 相似文献