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221.
Sainfort F Karsh BT Booske BC Smith MJ 《The Joint Commission journal on quality improvement》2001,27(9):469-483
BACKGROUND: Health care has used total quality management (TQM)/quality improvement (QI) methods to improve quality of care and patient safety. Research on healthy work organizations (HWOs) shows that some of the same work organization factors that affect employee outcomes such as quality of life and safety can also affect organizational outcomes such as profits and performance. An HWO is an organization that has both financial success and a healthy workforce. For a health care organization to have financial success it must provide high-quality care with efficient use of scarce resources. To have a healthy workforce, the workplace must be safe, provide good ergonomic design, and provide working conditions that help to mitigate the stress of health care work. INTEGRATING TQM/QI INTO THE HWO PARADIGM: If properly implemented and institutionalized, TQM/QI can serve as the mechanism by which to transform a health care organization into an HWO. To guide future research, a framework is proposed that links research on QI with research on HWOs in the belief that QI methods and interventions might be an effective means by which to create an HWO. Specific areas of research should focus on identifying the work organization, cultural, technological, and environmental factors that affect care processes; affect patient health, safety, and satisfaction; and indirectly affect patient health, safety, and satisfaction through their effects on staff and care process variables. SUMMARY: Integrating QI techniques within the paradigm of the HWO paradigm will make it possible to achieve greater improvements in the health of health care organizations and the populations they serve. 相似文献
222.
Huang Y Ewalt KL Tirado M Haigis R Forster A Ackley D Heller MJ O'Connell JP Krihak M 《Analytical chemistry》2001,73(7):1549-1559
Bioparticle separation, bioparticle enrichment, and electric field-mediated immune detection were carried out on microfabricated semiconductor chips utilizing ac and dc electric fields. Microscale separation on a chip surface having an active area of approximately 16 mm2 was demonstrated for a mixture of Bacillus globigii spores and Escherichia coli bacteria. Dielectrophoretic enrichment was performed by collecting target bioparticles from a flow stream in flow cells of 47.5 microL, achieving a 20-fold increase in the concentration of E. coli bacteria from a diluted sample, a 28-fold enrichment for peripheral blood mononuclear cells from red blood cells, and a 30-fold increase in white blood cells from diluted whole blood. The ability to manipulate and collect bioparticles and macromolecules at microfabricated electrodes with ac and dc fields was further illustrated in electric field-mediated immunoassays for analyzing the biological identities of E. coli bacteria and B. globigii spores. According to these results, the electric methods for manipulating bioparticles present themselves as viable techniques for novel biomedical applications in sample preparations and biochemical assays on microelectrode arrays. 相似文献
223.
A new method for pulse oximetry is presented that possesses an inherent insensitivity to corruption by motion artifact, a primary limitation in the practical accuracy and clinical applicability of current technology. Artifact corruption of the underlying photoplethysmographic signals is reduced in real time, using an electronic processing methodology that is based upon inversion of a physical artifact model. This fundamental approach has the potential to provide uninterrupted output and superior accuracy under conditions of sustained subject motion, therefore, widening the clinical scope of this useful measurement. A new calibration technique for oxygen saturation is developed for use with these processed signals, which is shown to be a generalization of the classical Interpretation. The detailed theoretical and practical issues of Implementation are then explored, highlighting important engineering simplifications implicit in this new approach. A quantitative investigation of the degree of insensitivity to artifact is also undertaken, with the aid of a custom electronic system and commercial pulse oximeter probes, which is compared and contrasted with the performance of a conventional implementation. It is demonstrated that this new methodology results in a reduced sensitivity to common classes of motion artifact, while retaining the generality to be combined with conventional signal processing techniques 相似文献
224.
Detection of viable Cryptosporidium parvum using DNA-modified liposomes in a microfluidic chip 总被引:1,自引:0,他引:1
This paper describes a microfluidic chip that enables the detection of viable Cryptosporidium parvum by detecting RNA amplified by nucleic-acid-sequence-based amplification (NASBA). The mRNA serving as the template for NASBA is produced by viable C. parvum as a response to heat shock. The chip utilizes sandwich hybridization by hybridizing the NASBA-generated amplicon between capture probes and reporter probes in a microfluidic channel. The reporter probes are tagged with carboxyfluorescein-filled liposomes. These liposomes, which generate fluorescence intensities not obtainable from single fluorophores, allow the detection of very low concentrations of targets. The limit of detection of the chip is 5 fmol of amplicon in 12.5 microL of sample solution. Samples of C. parvum that underwent heat shock, extraction, and amplification by NASBA were successfully detected and clearly distinguishable from controls. This was accomplished without having to separate the amplified RNA from the NASBA mixture. The microfluidic chip can easily be modified to detect other pathogens. We envision its use in mu-total analysis systems (mu-TAS) and in DNA-array chips utilized for environmental monitoring of pathogens. 相似文献
225.
An electrodynamic balance was used to levitate a single methanol droplet while it evaporated down to, and just beyond, its first encountered Coulomb fission limit as ascertained by the time dependence of its laser light scatter signal. At its Coulomb limit, the primary droplet fragmented and approximately 81% of its net charge was released in the form of small droplets that are termed progeny. The window of time over which the progeny droplets were ejected from the electrodynamic balance was deltat = 850 ms, indicating that these droplets were formed with a range of mass-to-charge values. An average of 13.2 (+/-4.4) progeny droplets were detected as a result of this fragmentation event. On the assumption that the average initial radius of the progeny droplets were one-tenth the radius of the droplet undergoing the Coulomb fission event, approximately 50% of the total net charge ejected would not have been carried by the 13 progeny droplets detected. 相似文献
226.
Advances in instrumentation used for particle compositional analysis have enabled real-time identification and classification of individual particles. However, precise quantitation of individual particle compositions has been elusive. Here, we demonstrate that real-time quantitative single-particle compositional analysis is possible. This is illustrated for individual particles of sodium chloride (70 nm), ammonium sulfate (70 nm), and silica (40-2000 nm) using a real-time aerosol mass spectrometer. Atomic fractions for major components (> 1% concentration) of individual multicomponent particles have been measured within +/-20% accuracy. Trace element detection limits of 20 ppm are also demonstrated when individual particle compositions are ensemble averaged. 相似文献
227.
Felix CL Bewley WW Vurgaftman I Bartolo RE Stokes DW Meyer JR Yang MJ Lee H Menna RJ Martinelli RU Garbuzov DZ Connolly JC Maiorov M Sugg AR Olsen GH 《Applied optics》2001,40(6):806-811
We review the recent progress of electrically injected and optically pumped mid-IR lasers based on antimonide quantum wells with the type II W configuration. W quantum-well diodes have achieved cw operation up to 195 K at lambda = 3.25 mum. Optically pumped devices that employ the diamond pressure bond heat sink have reached 290 K at 3 mum and 210 K at 6 mum. Pulsed power conversion efficiencies of up to 7% at 220 K have been attained by use of an optical pumping injection cavity approach, in which an etalon cavity for the pump beam significantly enhances its absorptance. The angled-grating distributed-feedback configuration has been used to obtain near-diffraction-limited output for an optical pumping stripe width of 50 mum. 相似文献
228.
A sensor is described for which interference measurements of the phase delay between two propagating modes of different orders in a slab thin-film waveguide are used as the sensing technique. The basic building block of the sensor is a polymer film doped with an indicator dye such as Bromocresol Purple. The modes of two orders such as TM(0) and TM(1) are simultaneously excited in the light-guiding film with a focusing optics and a prism coupler. The modes are decoupled from the film and recombined to produce an interference pattern in the face of an output optical fiber. The sensitivity of the sensor to the ambient temperature change is 1.5 degrees C, and the sensitivity to NH(3) is 200 parts in 10(6) for one full oscillation of the signal. 相似文献
229.
A Series of comparisons were conducted to test the capabilities of a range of metrological techniques and analytical laboratories engaged in the assay of thorium in the workplace. The results of these exercises are presented together with the decision criteria used to determine whether results are significantly different from the true value. The discussion highlights those aspects which warrant closer and further attention. 相似文献
230.
Permeable reactive barriers (PRB) are being used to engineer favorable field conditions for in-situ remediation efforts. Two redox adjustment barriers were installed to facilitate a 10-month research effort on the fate and transport of MTBE (methyl tert-butyl ether) at a site called the Michigan Integrated Remediation Technology Laboratory (MIRTL). Thirty kilograms of whey were injected as a slurry into an unconfined aquifer to establish an upgradient reductive zone to reduce O2 concentration in the vicinity of a contaminant injection source. To minimize the impact of contaminant release, 363 kg of oxygen release compound (ORC) were placed in the aquifer as a downgradient oxidative barrier. Dissolved oxygen and other chemical species were monitored in the field to evaluate the effectiveness of this technology. A transient one-dimensional advective-dispersive-reaction (ADR) model was proposed to simulate the dissolved oxygen transport. The equations were solved with commonly encountered PRB initial and constant/variable boundary conditions. No similar previous solution was found in the literature. The in-situ lifetimes, based on variable source loading, were estimated to be 1,661 and 514 days for the whey barrier and ORC barrier, respectively. Estimates based on either maximum O2 consumption/production or measured O2 curves were found to under- or overestimate the lifetime of the barriers. The pseudo-first-order rate constant of whey depletion was estimated to be 0.303/d with a dissolution rate of 0.04/d. The oxygen release rate constant in the ORC barrier was estimated to be 0.03/d. This paper provides a means to design and predict the performance of reactive redox barriers, especially when only limited field data are available. 相似文献