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31.
HU Kasper G Haroske U Geissler W Meyer KD Kunze 《Canadian Metallurgical Quarterly》1997,19(6):482-488
OBJECTIVE: For approximately 15 years, malignancy-associated changes (MACs) have been consistently found by means of high-resolution cytometry in different tissues, especially in visually normal appearing cervical cells. Their biologic nature is not yet fully understood. The aim of this investigation was to assess the expression of MACs in cervical smears and to evaluate their prognostic relevance. STUDY DESIGN: This study was performed on normal intermediate cells obtained from 53 cytologically positive and 78 cytologically negative cervical smears. From a second sample, 31 cases showing negative cytology were selected for a prospective longitudinal study. Densitometric and texture features were generated, and MACs were described on the basis of multivariate discriminant analysis. RESULTS: Discrimination between positive and negative cases was possible, with a correct classification rate of approximately 80%. After a mean period of 29.5 months, we noted no statistically significant increase in the incidence of cervical intraepithelial neoplasia in the group of healthy but MAC-positive women as compared to those who were MAC negative. CONCLUSION: MACs were constantly expressed in the epithelium of the cervix. Although their prognostic relevance remains unclear, MACs play an important role in the effort to automate cervical cytology. 相似文献
32.
TJ Meyer SE Eveloff MS Bauer WA Schwartz NS Hill RP Millman 《Canadian Metallurgical Quarterly》1994,105(4):1211-1216
Sleep deprivation and fragmentation occurring in the hospital setting may have a negative impact on the respiratory system by decreasing respiratory muscle function and ventilatory response to CO2. Sleep deprivation in a patient with respiratory failure may, therefore, impair recovery and weaning from mechanical ventilation. We postulate that light, sound, and interruption levels in a weaning unit are major factors resulting in sleep disorders and possibly circadian rhythm disruption. As an initial test of this hypothesis, we sampled interruption levels and continuously monitored light and sound levels for a minimum of seven consecutive days in a medical ICU, a multiple bed respiratory care unit (RCU) room, a single-bed RCU room, and a private room. Light levels in all areas maintained a day-night rhythm, with peak levels dependent on window orientation and shading. Peak sound levels were extremely high in all areas representing values significantly higher than those recommended by the Environmental Protection Agency as acceptable for a hospital environment. The number of sound peaks greater than 80 decibels, which may result in sleep arousals, was especially high in the intensive and respiratory care areas, but did show a day-night rhythm in all settings. Patient interruptions tended to be erratic, leaving little time for condensed sleep. We conclude that the potential for environmentally induced sleep disruption is high in all areas, but especially high in the intensive and respiratory care areas where the negative consequences may be the most severe. 相似文献
33.
R. Laroy R. Todt R. Meyer M.-C. Amann G. Morthier R. Baets 《Photonics Technology Letters, IEEE》2006,18(12):1293-1295
The possibility to directly modulate widely tunable lasers up to several gigahertz is desirable in telecom applications. We discuss the dynamic properties of the recently proposed widely tunable twin-guide laser concept. It has promising prospects with a maximum theoretical bandwidth above 20 GHz and the 3-dB bandwidth at 250 mA indicates that an actual bandwidth of 12 GHz should be possible. The current lasers were not designed for high-speed modulation, so only 1-GHz modulation can be reached at the moment. 相似文献
34.
Use of modelling for optimization and upgrade of a tropical wastewater treatment plant in a developing country. 总被引:1,自引:0,他引:1
D Brdjanovic M Mithaiwala M S Moussa G Amy M C M van Loosdrecht 《Water science and technology》2007,56(7):21-31
This paper presents results of a novel application of coupling the Activated Sludge Model No. 3 (ASM3) and the Anaerobic Digestion Model No.1 (ADM1) to assess a tropical wastewater treatment plant in a developing country (Surat, India). In general, the coupled model was very capable of predicting current plant operation. The model proved to be a useful tool in investigating various scenarios for optimising treatment performance under present conditions and examination of upgrade options to meet stricter and upcoming effluent discharge criteria regarding N removal. It appears that use of plant-wide modelling of wastewater treatment plants is a promising approach towards addressing often complex interactions within the plant itself. It can also create an enabling environment for the implementations of the novel side processes for treatment of nutrient-rich, side-streams (reject water) from sludge treatment. 相似文献
35.
9月25日,正值中国传统节日中秋佳节,德州仪器(TI)无线通信事业部门的高层领导及其合作伙伴在"无线通信创新无限"-2007德州仪器无线高峰论坛上汇聚一堂,对无线通信技术的创新与应用,未来无线通信市场的机遇与挑战进行了深度沟通与探讨.论坛现场还实机演示了TI各项最新的手机技术应用,气氛融洽愉快. 相似文献
36.
Martin Meyer 《Scientometrics》2007,70(3):779-810
This contribution formulates a number of propositions about the emergence of novel nanoscience and nanotechnology (N&N). Seeking
to complement recent work that aims to define a research agenda and draws on general insights from the innovation literature,
this paper aims to synthesize knowledge from innovation-related studies of the N&N field. More specifically, it is suggested
that N&N is often misconstrued as either a field of technology or an area of (broadly) converging technologies while evidence
to date suggests rather that N&N be considered a set of inter-related and overlapping about not necessarily merging technologies.
The role of instrumentation in connecting the various N&N fields is underlined. Finally, the question is raised whether change
in N&N tends to be incremental rather than discontinuous, being the result of technological path-dependencies and lock-ins
in industry-typical search regimes that are only slowly giving way to more boundary-crossing activities. 相似文献
37.
R. Meyer Hilde Hardtdegen R. Carius D. Grützmacher M. Stollenwerk P. Balk A. Kux B. Meyer 《Journal of Electronic Materials》1992,21(3):293-298
This paper presents a study of the structural and optical properties of strained GaInAs/ InP multiple quantum well (MQW) structures
fabricated by LP-MOVPE. The composition of the Ga
x
In1−x
As films ranged fromx = 0.17 tox = 1.0 and was determined by sputtered neutral mass spectrometry (SNMS) on thick layers. The structures of the MQW samples
with well widths from 1.5 to 5 nm were investigated by high resolution x-ray diffraction (HR-XRD). Simulations of the diffraction
patterns showed that transition layers of approximately 2 monolayer (ML) thickness with high lattice mismatch exist at the
interfaces. Photoluminescence (PL) measurements indicate well widths of a multiple of a monolayer with local variations of
one monolayer. The PL peak energies vary smoothly with the Ga concentration. These results were confirmed by optical absorption
measurements. 相似文献
38.
Using recent original data from three different sources, the article exhibits some strengths and weaknesses of science in Colombia. It shows that research in this country is in a process of growth although recent results of this positive trend are still to be confirmed. Comparing the evolution of science in Colombia with that of Latin America as a whole, describing and explaining its geographical and institutional concentration as well as its thematic distribution, it also reveals the interdependance between science production dynamics and international cooperation programmes. A basic argument is that the development of science in this country, even though it is fragile and erratic, does not lack sound bases. The indicators used suggest indeed an autonomous scientific motion and inspiration which does not contradict the internationalization process of Colombian science but rectifies the picture of an excessively isolated or dependent community that used to be portrayed. 相似文献
39.
The original Smoking Consequences Questionnaire (SCQ; T. H. Brandon & T. B. Baker, 1991) measured college students' outcome expectancies for cigarette smoking. A version (SCQ-Adult) was needed for assessing expectancies in more typical, older, nicotine-dependent smokers. Two separate versions of the SCQ were developed and compared. Tests of construct validity provided greater support for the version comprising probability items over the version comprising subjective expected utility items. As expected, principal components analyses revealed a greater number of factors than the original SCQ suggesting that expectancies become more specific with smoking experience. All scales showed good reliability. Over the course of smoking cessation treatment, expectancies became less positive, especially for abstaining participants. Other validity tests also tended to be consistent with research on alcohol expectancies and with contemporary models of drug outcome expectancies. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
40.