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51.
K Basen-Engquist GS Parcel R Harrist D Kirby K Coyle S Banspach D Rugg 《Canadian Metallurgical Quarterly》1997,67(9):365-371
Randomized trials of school-based health promotion programs present unique design and analytical issues not widely discussed in the research literature. This article describes the Safer Choices study--a school-based program for prevention of HIV, other sexually transmitted diseases, and pregnancy--to illustrate critical methodological issues involved in large-scale, school-based intervention trials, particularly those evaluating interventions with a school-wide focus. The issues presented are: 1) comparability of the intervention and control groups even when few units are randomized; 2) factors that affect the decision to use a cohort or cross-sectional design; and 3) appropriate analysis strategy when the unit of randomization and intervention is at the school level, but observations are at the student level. 相似文献
52.
Here we investigate the problem of transforming a nonlinear system on the torusT
n
by using global feedback and global changes of coordinates into an invariant system (i.e., a control system
of whichf andg
i
are (left and right) invariant vector fields whenT
2 is considered as a Lie group). We provide a complete answer whenn=2 and give a sufficient condition and necessary conditions in the more general case. 相似文献
53.
54.
Discrete-Time Expectation Maximization Algorithms for Markov-Modulated Poisson Processes 总被引:1,自引:0,他引:1
55.
Software developers often need to understand a large body of unfamiliar code with little or no documentation, no experts to consult, and little time to do it. A post appeared in January 2008 on Slashdot, a technology news Web site, asking for tools and techniques that could help. This article analyzes 301 often passionate and sometimes articulate responses to this query, including the themes and the associated tool recommendations. The most common suggestions were to use a code navigation tool, use a design recovery tool, use a debugger to step through the code, create a runtime trace, use problem-based learning, ask people for help, study the code from top down, and print out all the code. This analysis presents an intriguing snapshot of how software developers in industry go about comprehending big code. 相似文献
56.
Using electric actuation and detection of oscillations in microcantilevers for pressure measurements
Gayatri Keskar Bevan Elliott Jay Gaillard Malcolm J. Skove Apparao M. Rao 《Sensors and actuators. A, Physical》2008,147(1):203-209
Response characteristics of a microcantilever, such as resonant frequency, amplitude, phase and quality factor, can be used for absolute pressure measurements in the range of 10−4 to 103 Torr. To this end, it would be very convenient to have the resonance of the microcantilever actuated and detected electrostatically. Herein, we report the nonlinear dynamics of microcantilevers under varying pressure and different gases using the harmonic detection of resonance (HDR) technique [J. Gaillard, M.J. Skove, R. Ciocan, A.M. Rao, Electrical detection of oscillations in 340 microcantilevers and nanocantilevers, Rev. Sci. Instrum. 77 (2006) 073907]. The HDR technique exploits nonlinearities in the cantilever-counter electrode system to allow electrostatic actuation and detection of the responses of the microcantilever to the pressure and gas composition. In particular, the 2nd and 3rd harmonics of the measured charge on the cantilever are investigated. The microcantilever demonstrates a quality factor of 10,000 at 10−3 Torr, and a usable response in the range from 10−3 to 103 Torr. The use of different harmonics can enable us to adjust the range of pressures over which the sensor has an efficacious response, enhancing its sensitivity to a particular environment. The experimental results are in reasonable agreement with theoretical calculations, despite the nonlinearities involved. 相似文献
57.
Jenkins RE Meng X Elliott VL Kitteringham NR Pirmohamed M Park BK 《Proteomics. Clinical applications》2009,3(6):720-729
Flucloxacillin is a synthetic penicillin used in the treatment of Staphylococcal infections. Adverse reactions to the drug are believed to arise through covalent modification of proteins, with tissue damage occurring secondary to an immune reaction. Serum proteins have been shown by adduct-specific antibodies to be modified by flucloxacillin, but the nature and sites of modification have not been characterised. Here, in vitro studies on HSA have shown by MS that the modification of protein lysine residues occurs in a dose-, time- and site-dependent manner. Affinity, cation exchange and reversed phase chromatography prior to MS revealed in vivo modification of HSA with flucloxacillin in tolerant patients, with up to nine modified lysine residues being detected in each patient, and with modification of Lys190 and Lys212 being detected in 8/8 patients. It was also revealed for the first time that plasma proteins could be modified with the 5-hydroxymethyl metabolite of flucloxacillin, and that essentially the same Lys residues were targeted by both the parent drug and its metabolite. This study provides a detailed characterisation of sites of chemical modification of an endogenous target and reveals candidate peptides for T-cell and antibody assays of flucloxacillin hypersensitivity. 相似文献
58.
GS Barolin 《Canadian Metallurgical Quarterly》1995,145(19-20):568-576
Together with building up a first neurological department in one of the Austrian states we could introduce and organize the 1st scientific institute in literature for neuro-rehabilitation and -prophylaxis. 80% of the neuro-rehabilitation-patients are geriatrics. Hence overlapping of neuro-rehabilitation with rehabilitation in old age is to be postulated. "Rehabilitation of old age groups" as well has been named by us for the 1st time in scientific literature. Moreover we operate such activities on a large scale within a practical and social medical context. As worldover (at least within the civilized countries of high standards) the problem of old age groups is a steadily increasing and important, we are working on a very important scientific sector. Our slogan: "Holistic and permanent" is practically operated as follows: 1. Fluent transition of rehabilitation-adequate acute treatment towards a systematic specialized rehabilitation. 2. Schooling of relatives and follow up rehabilitation service. 3. Introducing rehabilitative thoughts as well in university, teaching as (by separate schoolings) within medical profession and all the other health professions. 4. We emphasize a plurality of methods; to be named here as main examples: integrated physiotherapy as well as integrated psychotherapy. Emphasizing more scientific values for (high age-)rehabilitation, we emphasize as well that it must not be banned into "high age ghettos". Contrarely rehabilitation adapted thinking must be integrated within all the health professions. 5. Innovation, phantasy and pleasure must be introduced into our work. We report of work with lay-groups, animal-visits, hippo-therapy, music, etc. This forms a large interesting territory for an upraising young generation in health professions. 相似文献
59.
P Romero PR Dunbar D Valmori M Pittet GS Ogg D Rimoldi JL Chen D Liénard JC Cerottini V Cerundolo 《Canadian Metallurgical Quarterly》1998,188(9):1641-1650
Characterization of cytolytic T lymphocyte (CTL) responses to tumor antigens has been impeded by a lack of direct assays of CTL activity. We have synthesized reagents ("tetramers") that specifically stain CTLs recognizing melanoma antigens. Tetramer staining of tumor-infiltrated lymph nodes ex vivo revealed high frequencies of tumor-specific CTLs which were antigen-experienced by surface phenotype. In vitro culture of lymph node cells with cytokines resulted in very large expansions of tumor-specific CTLs that were dependent on the presence of tumor cells in the lymph nodes. Tetramer-guided sorting by flow cytometer allowed isolation of melanoma-specific CTLs and confirmation of their specificity and their ability to lyse autologous tumor cells. Our results demonstrate the value of these novel reagents for monitoring tumor-specific CTL responses and for generating CTLs for adoptive immunotherapy. These data also indicate that strong CTL responses to melanoma often occur in vivo, and that the reactive CTLs have substantial proliferative and tumoricidal potential. 相似文献
60.
A discrete-time control problem of a finite-state hidden Markov chain partially observed in a fractional Gaussian process is discussed using filtering. The control problem is then recast as a separated problem with information variables given by the unnormalized conditional probabilities of the whole path of the hidden Markov chain. A dynamic programming result and a minimum principle are obtained. 相似文献