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81.
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83.
Porous Si layers up to 250 μm in thickness are used to isolate spiral inductors from low resistivity substrates. Wafer curvature and secondary ion mass spectroscopy (SIMS) analysis are done to address the manufacturability issue of porous Si. Spiral inductors with a single level Al on 2 in, p-type substrates of 0.008 Ω-cm resistivity are demonstrated with Q<6 at 3 GHz for an L of ~8 nH. Large inductors with L~100 nH have been shown with the first resonance frequency at 1 GHz. The expected performance potential as well as factors that could be limiting the Q are discussed  相似文献   
84.
Individual monitoring regulations in Switzerland are based on the ICRP60 recommendations. The annual limit of 20 mSv for the effective dose applies to the sum of external and internal radiation. External radiation is monitored monthly or quarterly with TLD, DIS or CR-39 dosemeters by 10 approved external dosimetry services and reported as H(p)(10) and H(p)(0.07). Internal monitoring is done in two steps. At the workplace, simple screening measurements are done frequently in order to recognise a possible incorporation. If a nuclide dependent activity threshold is exceeded then one of the seven approved dosimetry services for internal radiation does an incorporation measurement to assess the committed effective dose E(50). The dosimetry services report all the measured or assessed dose values to the employer and to the National Dose Registry. The employer records the annually accumulated dose values into the individual dose certificate of the occupationally exposed person, both the external dose H(p)(10) and the internal dose E(50) as well as the total effective dose E = H(p)(10)+E(50). Based on the national dose registry an annual report on the dosimetry in Switzerland is published which contains the statistics for the total effective dose, as well as separate statistics for external and internal exposure.  相似文献   
85.
Hack E  Frei B  Kästle R  Sennhauser U 《Applied optics》1998,37(13):2591-2597
The addition correlation of two speckle fields by simultaneousillumination at different wavelengths is used for object contouring ina Twyman-Green-type interferometer. Fringe visibility is enhancedwhen the stochastic speckle background intensity obtained from areference plane modulation is subtracted. We calculate the contourphase map by using a phase-shift algorithm in the syntheticwavelength. A comparison with a sequential illumination, phasedifference method based on a laser wavelength phase shift isgiven. The test setup does not need to be stable on aninterferometric scale, and therefore a method is provided that lendsitself to applications in noisy environments.  相似文献   
86.
Automatic controllers capable of regulating multiple patient outputs for higher-quality anesthesia treatment are described. The first steps toward the development of an autonomous anesthesia system at the authors' laboratory are presented. The controllers are implemented on a real-time platform and tested on humans to quantify the benefits that may result from their use in routine practice. To date, the staff at the University Hospital in Bern can rely on controllers that regulate six different patient outputs. Overall, more than 150 patients were treated with closed-loop controllers during general anesthesia. These controllers regulate O2, CO2, and inspired and expired anesthetic gas concentrations in the breathing system, as well as mean arterial pressure and depth of hypnosis through bispectral index  相似文献   
87.
Fourteen Sprague-Dawley rats were exposed to pulses produced by a Bournlea ultra-wideband (UWB) pulse generator (rise time, 318-337 ps; maximum E field, 19-21 kV/m). Exposures at a repetition frequency of 1 kHz for 0.5 s or to repetitive pulse trains (2-s exposure periods alternating with 2 s of no exposure, for a total of 2 min) resulted in no significant changes in heart rate or mean arterial blood pressure. These results suggest that acute whole-body exposure to UWB pulses does not have a detrimental effect on the cardiovascular system  相似文献   
88.
We have previously shown that the sparkling gene, which like mammalian Pax2 plays an important role in eye development, is encoded by the Drosophila homolog of Pax2. Here we demonstrate that D-Pax2 also encodes the shaven function, which is crucial during bristle development. Both sv and spa alleles, previously thought to represent different genes, are mutations in two widely separated enhancers of D-Pax2. The sv function of D-Pax2 acts in at least two distinct steps of mechanosensory bristle development: the specification of the alternative fate of shaft as opposed to socket cell, and later the differentiation of the shaft cell.  相似文献   
89.
The most important variables for the clinical use of antitumor agents (AAs) are dose and combination chemotherapy. The objectives of this study were to analyze the relationship between these two variables and to propose a unified conceptual framework for the construct and interpretation of clinical trials. Definitions and variables with respect to dose include potency, therapeutic index, standard dose, efficacy, relative efficacy, dose-limiting toxicity (DLT), dose rate, dose density, dose intensity, and fractional dose intensity. Our overarching concept, that is, summation dose intensity (SDI), was calculated in several ways, depending upon the nature of the data, and included the relative efficacy method, the unit regimen method, and the high dose method. The SDI concept was then applied to disease categories and strategies to determine its usefulness and effectiveness in integrating dose and combinations. The tumors and settings were: mustargen-vincristine-procarbazine-prednisone in Hodgkin's disease, combination chemotherapy for acute lymphocytic leukemia in children, metastatic breast cancer including dose and combinations, selected other solid tumors, alternating chemotherapy, and high dose studies in the leukemias and lymphomas. SDI was effective in integrating and quantifying dose and combination chemotherapy. For classical AAs, the implication of SDI for the construct and analysis of clinical trials was emphasized. In addition to new drug development, emphasis should be given to reducing or eliminating DLTs, such as those of the marrow, now and, in the future, those of the gastrointestinal tract toxicity and other DLTs. The above was derived from and applies to the classical AAs. Whether they will apply to, with appropriate adjustment, agents with significantly different dose-response curves, such as biotherapeutics and hormonal agents, remains to be determined.  相似文献   
90.
H. Sun  F. Blatter  H. Frei 《Catalysis Letters》1997,44(3-4):247-253
Oxidation of propane by O2 to acetone was observed in solvent-free BaY and CaY under irradiation with visible light as well as under dark thermal conditions. The reaction was monitored in situ by FT-infrared spectroscopy. In the case of the photochemical oxidation, isopropyl hydroperoxide was detected as reaction intermediate. No byproduct was observed even upon > 50% conversion of the alkane. Ethane was oxidized completely selectively to acetaldehyde in CaY under irradiation with blue light. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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