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101.
A growing interest has been focused on silicon on insulator (SOI) technologies over the past years. Yet, few studies were carried out regarding the integration of vertical SiGe heterojunction bipolar transistors (HBTs) using such substrates. This paper deals both with the integration of a SiGeC HBT on thin-film CMOS-compatible SOI, and a comprehensive study of its electrical behavior based on physical simulation and electrical characterization. Various aspects of the optimization of device performances are described, considering process or layout improvements.  相似文献   
102.
Reviews the book, Transference. Its meaning and function in psychoanalytic therapy by Benjamin Wolstein. Introduction by Clara Thompson (1954). After a lucid introduction by Clara Thompson, which summarizes historical trends in the concept of transference, the author clarifies the objectives of the monograph. Essentially this is a critical study, by no means pretending to be a comprehensive survey of the field. There is an initial attempt to orient the reader toward certain basic scientific postulates from which the conception of transference is derived. Wolstein attempts to orient the reader toward the essential philosophical assumptions which underlie the theoretical constructs of Freud, who worked essentially in the atmosphere of a mechanistic, monistic, reductive scientific world. This is undoubtedly a difficult, somewhat overwritten, and occasionally exasperating book, but it is a brilliant one that raises important issues, faces up to them squarely, and goes to the core of many problems in current psychotherapeutic theory and technique. Practicing therapists, personality theorists, social scientists, and advanced graduate students will find it stimulating and provocative of serious self-searching. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
103.
Tetramethylammonium 3-aminopropyl dimethylsilanolate, readily prepared from bis(3-aminopropyl) tetramethyldisiloxane and tetramethyl-ammonium hydroxide pentahydrate, has been found to serve as a highly effective catalyst for the ring opening polymerization of cyclic siloxanes with an end blocker such as bis(3-aminopropyl) tetramethyldisiloxane to give aminopropyl terminated linear polydimethylsiloxanes. By following a novel two stage procedure, even high molecular weight (5,000–55,000 g/mol) silicone diamines were able to be prepared in a high state of purity; chain extension reactions of these diamines with diisocyanates gave a series of high molecular weight silicone polyureas with good elastomeric properties.  相似文献   
104.
Repeated measures designs involving nonorthogonal variables are being used with increasing frequency in cognitive psychology. Researchers usually analyze the data from such designs inappropriately, probably because the designs are not discussed in standard textbooks on regression. Two commonly used approaches to analyzing repeated measures designs are considered in this article. It is argued that both approaches use inappropriate error terms for testing the effects of independent variables. A more appropriate analysis is presented, and two alternative computational procedures for the analysis are illustrated. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
105.
There are three approaches to DNA identification: tectonic, halieutic and icarian, of which the tectonic is sensible, the halieutic impractical, and the icarian idiotic. The rationale and consequences of these approaches are detailed.  相似文献   
106.
107.
Optical transmittance and reflectance of a translucent plastic PTFE film have been measured over the solar wavelength range using different integrating spheres. The same sample has been measured with small and large spheres and the total solar transmittance has been obtained from both broad band measurements and from integration of spectral data. The fact that the sum of reflectance and transmittance often exceeds 100% shows that all types of spheres tend to overestimate the transmittance of this highly scattering sample. This error can be attributed to the sphere geometry in combination with the light scattering properties of the sample, and unless proper correction of recorded data is carried out the error may be as large as 5–10%. Some specific errors are presented and an approximate correction procedure is suggested.These results show that there is a need for a transmittance standard which can be used to calibrate integrating spheres. Such a standard with negligible thickness would be especially useful for measurements with large, broadband integrating spheres, but would also be helpful for the correct handling of data from small spectral instruments.  相似文献   
108.
Neutrophils expressing cyclooxygenase-2 (COX-2) extensively infiltrate maternal blood vessels in preeclampsia, associated with vascular inflammation. Because pregnancy neutrophils also express protease-activated receptor 1 (PAR-1, F2R thrombin receptor), which they do not in non-pregnant subjects, they can be activated by proteases. We tested the hypothesis that aspirin at a dose sufficient to inhibit COX-2 would reduce inflammatory responses in preeclampsia neutrophils. Neutrophils were isolated from normal pregnant and preeclamptic women at approximately 30 weeks’ gestation. Normal pregnancy neutrophils were treated with elastase, a protease elevated in preeclampsia, or elastase plus aspirin to inhibit COX-2, or elastase plus pinane thromboxane, a biologically active structural analog of thromboxane and a thromboxane synthase inhibitor. Preeclamptic pregnancy neutrophils were treated with the same doses of aspirin or pinane thromboxane. Confocal microscopy with immunofluorescence staining was used to determine the cellular localization of the p65 subunit of nuclear factor-kappa B (NF-κB) and media concentrations of thromboxane were measured to evaluate the inflammatory response. In untreated neutrophils of normal pregnant women, p65 was localized to the cytosol. Upon stimulation with elastase, p65 translocated from the cytosol to the nucleus coincident with increased thromboxane production. When neutrophils were co-treated with aspirin or pinane thromboxane, elastase was not able to cause nuclear translocation of p65 or increase thromboxane. In untreated neutrophils of preeclamptic women, the p65 subunit was present in the nucleus and thromboxane production was elevated, but when preeclamptic neutrophils were treated with aspirin or pinane thromboxane, p65 was cleared from the nucleus and returned to the cytosol along with decreased thromboxane production. These findings suggest that COX-2 is a downstream mediator of PAR-1 and demonstrate that PAR-1- mediated inflammation can be inhibited by aspirin. Given the extensive and ubiquitous expression of PAR-1 and COX-2 in preeclamptic women, consideration should be given to treating women with preeclampsia using a dose of aspirin sufficient to inhibit COX-2.  相似文献   
109.
This paper presents a stochastic method to estimate the multijoint mechanical impedance of the human arm suitable for use in a clinical setting, e.g., with persons with stroke undergoing robotic rehabilitation for a paralyzed arm. In this context, special circumstances such as hypertonicity and tissue atrophy due to disuse of the hemiplegic limb must be considered. A low-impedance robot was used to bring the upper limb of a stroke patient to a test location, generate force perturbations, and measure the resulting motion. Methods were developed to compensate for input signal coupling at low frequencies apparently due to human-machine interaction dynamics. Data was analyzed by spectral procedures that make no assumption about model structure. The method was validated by measuring simple mechanical hardware and results from a patient's hemiplegic arm are presented.  相似文献   
110.
The aim of this work was to investigate several different yttrium introduction routes to improve the high temperature oxidation resistance of a Fe‐20Cr‐5Al model alloy. Y2O3 sol‐gel coatings, Y2O3 metal‐organic chemical vapor deposition (MOCVD) coatings, yttrium ion implantation and yttrium as alloying element (0.1 wt.%) were the different methods of introduction of the reactive element. Both isothermal and cyclic oxidation tests showed that the surface introduction of yttrium or yttrium oxide did not drastically improve the oxidation behavior of the steel. Complementary experiments were performed to understand the lack of major beneficial effects of the so‐treated samples. Two stage oxidation experiments under 200 mbar 16O2 and 18O2 followed by secondary neutral mass spectrometry (SNMS) were performed to understand the alumina scale growth mechanisms, according to the introduction route of the reactive element. The results exhibited that the yttrium induced an increase of the inward transport of oxygen through the alumina scale compared to the untreated specimen. Nevertheless, the outward transport of aluminum was generally observed, except for the specimen containing Y as alloying element, which exhibited only a single18O peak close to the metal/oxide interface. Phase transformations during the oxidation at 1100°C were registered by in‐situ X‐ray diffraction (XRD). The untreated alloy was only covered by a thin layer of α‐Al2O3. For implanted specimens, yttrium was incorporated in Y3Al5O12 and YAlO3 phases. All the YAlO3 is transformed into Y3Al5O12 after less than 10 h. For the MOCVD or the sol‐gel coated samples, the primary formed YAlO3 phase was progressively transformed into Y3Al5O12. For the Fe‐20Cr‐5Al‐0.1Y alloy, no yttrium containing phases could be detected, even after 40 h of oxidation test at 1100°C.  相似文献   
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