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91.
Thin epitaxial CdTe films were grown on CdTe(111)B substrates by the close-spaced sublimation (CSS) technique and were characterized over a range of experimental parameters. The source temperature was varied between 480°C and 540°C, maintaining an average constant source–substrate temperature difference ΔT of ∼130°C. Helium was used as a carrier gas at pressures between 2 Torr and 10 Torr. Scanning electron microscopy (SEM) and x-ray diffraction (XRD) were used to analyze the film morphology and structure. Growth rates ranging from 1 μm/h to 4 μm/h were observed, based on profilometer thickness measurements. The addition of a pre-growth heat treatment step and post-growth annealing treatment resulted in smooth CdTe(111) films. An evolution in growth morphology was demonstrated with SEM images and film quality was confirmed with XRD.  相似文献   
92.
We present the approximate polynomial expression for an ellipsoid with rotational symmetry about its major axis, which is on the y-z plane and at angle theta with respect to the z axis. These expressions have many possible useful applications in optics as shown. The main optical properties of these types of inclined ellipsoidal surface will be reviewed.  相似文献   
93.
We have assessed whether the combined exposure to arsenic (As) and fluoride (F) exerts a different effect than the exposure to As alone on the pattern of expression of apoptosis and inflammatory genes by immune cells. RNA was extracted from peripheral blood mononuclear cells from twenty individuals exposed or not to As or F or both. Then, cDNA was isolated, and the expression of 180 genes related to apoptosis and inflammation was tested by a cDNA array test. We found significant differences in the expression of 9 apoptosis and 15 inflammation genes in the three exposed groups compared to non-exposed individuals. In addition, subjects exposed to As or F or both showed different patterns of expression of at least 19 genes. Our data indicate that the combined exposure to As and F has a different effect on gene expression than the exposure to As or F alone.  相似文献   
94.
This study used an ecologic design based on data from 1990 to 1994 gathered from forensic, vital statistic, census, law enforcement and liquor licensing agencies to assess the relationship between liquor outlet density and alcohol-related health outcomes in New Mexico. Linear regression models show that suicide, alcohol-related crash, and alcohol-related crash fatality (adjusted for age, sex, and minority status) are significantly associated with liquor outlet density. Data also show that, compared with the first tertile, suicide and alcohol-related crash rates increase about 50% and the alcohol-related crash fatality rate two-fold with the third tertile of liquor outlet density. Greater availability of liquor outlets is associated with higher rates of suicide, alcohol-related crash, and alcohol-related crash fatality.  相似文献   
95.
OBJECTIVE: To evaluate the use of magnetic resonance imaging (MRI) in making clinical decisions when assessing nonhealing pressure ulcers and nonhealing myocutaneous flaps for the presence of an abscess, osteomyelitis, sinus tracts, and fluid collections. DESIGN: Retrospective review of patient charts and radiographic studies. SETTING: Regional spinal cord injury center. SUBJECTS: Twelve patients who had MRI as part of their evaluation for a nonhealing pressure ulcer or myocutaneous flap. RESULTS: Seven patients had MRI for preoperative evaluation, four with a previous flap that had recurrent breakdown and three with a new grade III or IV ulcer. Five patients had MRI for postoperative evaluation of myocutaneous flaps with delayed healing. MRI was useful in identifying osteomyelitis in three patients and sinus tracts that required surgical revision in six patients. MRI was also used in two patients to assess the size of fluid collections postoperatively in determining whether the patients should be mobilized after surgery. These chronic nonhealing wounds resulted in multiple admissions and lengthy hospital stays and required multiple surgical revisions. Patients who did poorly with healing or had repeated breakdown tended to have concurrent issues such as poor self care, increased age, increased time of spinal cord injury, poor nutrition, or other medical problems. CONCLUSION: Chronic nonhealing pressure ulcers and myocutaneous flaps can be difficult to treat and evaluate with conventional methods. There are multiple reasons for failure to heal. MRI can be a useful tool for identifying some of these factors including osteomyelitis, fluid collections, abcesses, and sinus tracts in the perioperative period. Identifying the appropriate patient populations and clinical indications for the optimal use of MRI should be subject of further study.  相似文献   
96.
97.
We describe a neural information retrieval system (NIRS), now in production within the Boeing Company, which has been developed for the identification and retrieval of engineering designs. Two-dimensional and three-dimensional representations of engineering designs are input to adaptive resonance theory (ART-1) neural networks to produce clusters of similar parts. The trained networks are then used to recall an appropriate cluster when queried with a new part design. This application is of great practical value to industry because it aids in the identification, retrieval, and reuse of engineering designs, potentially saving large amounts of nonrecurring costs. In this paper, we review the application, the neural architectures and algorithms, and then give the current status and the lessons learned in developing a neural network system for production use in industry.  相似文献   
98.
Intramuscular injection of mice with an adeno-associated virus (AAV) vector expressing herpes simplex virus type 2 glycoprotein B led to the generation of both gB-specific major histocompatibility complex class I-restricted cytotoxic T lymphocytes and anti-gB antibody. AAV-mediated immunization was more potent than plasmid DNA or protein in generating antibody responses.  相似文献   
99.
Non-insulin-dependent diabetes mellitus (NIDDM) is a chronic disabling disease, that shortens length of life and implies a high burden for a community. Its prevalence goes from 0 per cent in Papua, New Guinea to 34 per cent in Pima Indians. There are very few prevalence studies in Mexico, and the strength of association of the known risk factors with the occurrence of the disease is not established. A prevalence cross sectional study was carried out with users of a first level medical care unit, with a meter measure of capillary glucose levels. Those with a previous diagnosis of diabetes or whose capillary glucose level were 200 mg or over were considered diabetics. Hyperglycemia was when the levels were recorded between 121 and 199 mg. The crude prevalence of NIDDM was 5.6 per cent (CI 95% 4.5-6.8), With almost no sex difference. Hyperglycemia prevalence was 2.9 per cent (CI 95% 2.0-3.7). Age was the main risk factor for the development of NIDDM. Those between 40 and 59 years showed a high risk (OR 10.8; CI 95% 5.4-22.0; p < 0.0001), and it was greater for the 60 years or elder (OR 20.6; CI 95% 9.8-44.1; p < 0.0001). Weight was also an important risk factor, with a 2.7 fold greater risk for obese persons (CI 95% 1.6-4.6; p < 0.0001). Other, risk factors were familiar history of diabetes (OR 1.5; CI 95% 0.9-2.3; p = 0.096), and overcrowding (OR 1.9; CI 95% 1.0-3.4; p = 0.03). In order to analyze independently each variable, a logistic regression model was applied, and a similar strength of association was observed for the crude model, but for obesity whose effect was modified by age. When only new cases were analyzed in the former model, the association with obesity was maintained. There is a need to develop prevalence studies of NIDDM in Mexico and to measure the strength of association with the known and the not jet well known risk factors of this disease in order to establish health policies according to the Mexican reality.  相似文献   
100.
We present one case of osteochondroplastic tracheobronchopathy in a patient with right laterocervical tumoration as a manifestation of a normofunctional nodular goiter detected in a thyroid morphofunctional study, and tracheal stenosis secondary both to the goiter and the tracheobronchial process. The coincidence of these two processes, probably fortuitous, has never been described before.  相似文献   
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