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1.
BACKGROUND: In response to the increasing rate of skin cancer, particularly melanoma in the United States, the Environmental Protection Agency, the National Weather Service, the Centers for Disease Control and Prevention, National Association of Physicians for the Environment, and the American Academy of Dermatology, developed the Ultraviolet Index (UVI) to inform the public of the strength of the sun's rays and advise on methods for sun protection. OBJECTIVE: Our purpose was to evaluate the extent to which television stations and newspapers reported the UVI and assess the public's response to it. METHODS: To evaluate the effect of this effort, we surveyed television weather forecasters at 185 stations and examined weather pages in 54 newspapers in 58 cities that received the UVI reports. We also conducted a population probability telephone survey of 700 white adults (18 years of age and older) in these 58 cities. RESULTS: Seventy-one percent of the 169 stations that provided survey data for both 1994 and 1995 broadcast the UVI; 61% of newspapers reported the UVI. Nearly 64% of the 700 respondents (n = 445) had heard of the UVI. Of these respondents, 38% (n = 170) stated that they or their family changed their sun protection practices as a result of the UVI. CONCLUSION: The majority of television weather forecasters and newspapers reported the UVI. Most of the public was aware of the UVI, causing some to change sun protection practices. Further evaluation is required to maximize the effect of the UVI on sun protection practices. 相似文献
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The species from the tendons and sub-cutaneous tissue of the tarsal and carpal joints is identified as O. skrjabini Rukhlyadev, 1964 (this taxon, which was poorly defined and badly restored, is used instead of O. tarsicola to avoid dispute). O. skrjabini belongs to on homogeneous group of four species parasitic in Palearctic cervids, which seems to have evolved relatively recently. The morphological characteristics of the parasite of Capricornis are not sufficient to warrant the creation of a new taxon. The species from the subcutaneous tissue of the body is named O. suzukii n. sp. It belongs to a group comprising three species, parasites of antilocaprids and cervids from the Holarctic region and tropical domestic bovines, which seem to have evolved before the skrjabini group. The Japanese species does not present the hypertelic characters of the other species of the group. The microfilaria of O. suzukii is unknown. Thus it is not possible to say if this species is the same as one found in bovines (and, perhaps, in humans) in the Oita region of Kyushu Island. 相似文献
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Mohammed F. Bain M.F. Ruddell F.H. Linton D. Gamble H.S. Fusco V.F. 《Electron Devices, IEEE Transactions on》2005,52(7):1384-1391
The design and simulation of a novel silicon Schottky diode for nonlinear transmission line (NLTL) applications is discussed in this paper. The Schottky diode was fabricated on a novel silicon-on-silicide-on-insulator (SSOI) substrate for minimized series resistance. Ion implantation technology was used as a low-cost alternative to molecular beam epitaxy to approximate the delta (/spl delta/) doping profile, which results in strong nonlinear CV characteristics. The equivalent circuit model of the Schottky diode under reverse bias conditions was extracted from the S-parameter measurement performed on the diode. The measured CV characteristics show strong nonlinearity, the junction capacitance varies from 182 to 47.5 fF as the reverse bias voltage is varied from 0 to -5 V. A parasitic inductance of 40 pH was measured for the silicon Schottky diode, which is much smaller than a comparable sized GaAs Schottky diode. This small inductance is an advantage for the silicon Schottky diode offering improvement in the silicon NLTL performance. 相似文献
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BACKGROUND: Few studies have compared the incidence of deep venous thrombosis among ethnic groups. OBJECTIVE: To determine the incidence of deep venous thrombosis among ethnic groups. Design: Analysis of the linked California Patient Discharge Data Set from 1991 to 1994. Setting: California. PATIENTS: 17991 patients with idiopathic deep venous thrombosis (thrombosis without cancer or hospitalization within preceding 6 months) and 5573 patients with secondary thromboembolism (thromboembolism occurring within 3 months of seven different events). MEASUREMENTS: Ethnicity was determined by using race as documented in the data set. For idiopathic deep venous thrombosis, standardized age- and sex-adjusted incidences were calculated. For secondary thromboembolism, proportional hazards modeling was done. RESULTS: The annual incidence of idiopathic deep venous thrombosis per 1000000 persons older than 18 years of age was 230 for white persons, 293 for African Americans (rate ratio, 1.27 [95% CI, 1.07 to 1.51]), 139 for Hispanic persons (rate ratio, 0.60 [CI, 0.54 to 0.67]), and 60 for Asians and Pacific Islanders (rate ratio, 0.26 [CI, 0.22 to 0.30]). Compared with white persons, Asians and Pacific Islanders who developed secondary thromboembolism had a significantly lower relative risk (range, 0.22 to 0.61) for all seven conditions analyzed. CONCLUSIONS: Compared with white persons, Asians and Pacific Islanders have a very low incidence of idiopathic deep venous thrombosis and a very low relative risk for secondary venous thromboembolism. 相似文献
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C Bain R Keller GK Collington LR Trabulsi S Knutton 《Canadian Metallurgical Quarterly》1998,66(8):3900-3908
Elevated concentrations of intracellular calcium ([Ca]i) have been implicated as an important signalling event during attaching and effacing (A/E) lesion formation by enteropathogenic Escherichia coli (EPEC). The highly localized nature of the cytoskeletal and cell surface alterations occurring during A/E lesion formation suggests that there should be equally localized EPEC-induced signalling events. To analyze further the calcium responses to infection of HEp-2 cells by EPEC, we employed calcium-imaging fluorescence microscopy, which allows both temporal and spatial measurements of [Ca]i in live cells. Using this imaging technique, not only were we unable to detect any significant elevation in [Ca]i at sites of A/E EPEC adhesion, but, with several different classical EPEC and enterohemorrhagic E. coli (EHEC) strains and three different infection procedures, each of which resulted in extensive A/E bacterial adhesion, we were unable to detect any significant alterations in [Ca]i in infected cells compared to uninfected cells. In addition, chelation of intracellular free calcium with bis-(aminophenoxy)-ethane-N,N,N',N'-tetraacetic acid (BAPTA) did not, as previously reported, prevent A/E lesion formation. We conclude that increased [Ca]i are not required for A/E lesion formation by EPEC and EHEC. 相似文献
7.
Mehrdad Hamrahian Karen T. Pitman Éva Csongrádi Justin H. Bain Béla Kanyicska Tibor Fülöp 《Hemodialysis international. International Symposium on Home Hemodialysis》2012,16(4):571-576
We are reporting on a series of two patients with end‐stage renal disease on hemodialysis, presented for surgical parathyroidectomy secondary refractory hyperparathyroidism. Both patients had failed maximized medical managements, including higher‐than‐usual doses of the calcimimetic cinacalcet (270 and 180 mg/day, respectively). On physical exam, both patients had marked symmetrical craniofacial hypertrophy with coarse distortion of facial features, similar in appearance to past reports of Sagliker syndrome. On X‐ray and computed tomographic exam, they had peculiar areas of bone absorption on the skull, imitating the radiologic appearance of multiple myeloma. Bone biopsy of the maxilla, however, did not show the expected brown tumor, but rather described only fibrosis and reactive bone formations. This phenotype developed while being on cinacalcet, progressed despite escalation of therapy, and improved only after parathyroidectomy. Both patients developed massive “hungry bone syndrome” after parathyroidectomy necessitating prolonged IV calcium infusion. This pattern of severe facial distortion likely represented an adverse consequence of severe tertiary hyperparathyroidism, along with supraphysiologic dose of cinacalcet administration and 25‐hydroxy vitamin D deficiency in sensitive individuals. The genetic base of this observation remained unexplained. 相似文献
8.
To date, Inductive Logic Programming (ILP) systems have largely assumed that all data needed for learning have been provided at the onset of model construction. Increasingly, for application areas like telecommunications, astronomy, text processing, financial markets and biology, machine-generated data are being generated continuously and on a vast scale. We see at least four kinds of problems that this presents for ILP: (1) it may not be possible to store all of the data, even in secondary memory; (2) even if it were possible to store the data, it may be impractical to construct an acceptable model using partitioning techniques that repeatedly perform expensive coverage or subsumption-tests on the data; (3) models constructed at some point may become less effective, or even invalid, as more data become available (exemplified by the “drift” problem when identifying concepts); and (4) the representation of the data instances may need to change as more data become available (a kind of “language drift” problem). In this paper, we investigate the adoption of a stream-based on-line learning approach to relational data. Specifically, we examine the representation of relational data in both an infinite-attribute setting, and in the usual fixed-attribute setting, and develop implementations that use ILP engines in combination with on-line model-constructors. The behaviour of each program is investigated using a set of controlled experiments, and performance in practical settings is demonstrated by constructing complete theories for some of the largest biochemical datasets examined by ILP systems to date, including one with a million examples; to the best of our knowledge, the first time this has been empirically demonstrated with ILP on a real-world data set. 相似文献
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Eric Bain Wasmund Ken Coley Randal M. Shaubel Kevin O.P. Reynolds Josef Benedik 《Chemical engineering science》2010,65(14):4271-4284
The manufacture of many high value-added powders takes place by the decomposition of gaseous precursors in aerosol tube reactors. Historically, process improvements were achieved by making changes on the outside of the reactor and observing what comes out at the end of the pipe. The development of increasingly accurate aerosol dynamics models based on engineering first principles has been limited because models were typically validated on integral properties of ex situ product, instead of particle properties measured at multiple positions inside the reactor. In this study, a model reactor was equipped to capture samples thermophoretically from 15 internal positions. Additional in-line measurements were achieved with a multi-stage inertial impactor and by traditional analysis of ex situ product. Calculations were performed to verify that thermophoresis was the dominant mechanism of particle capture. The thermophoretic samples were analyzed by electron beam microscopy and image analysis to develop particle size distributions at each of the internal positions inside the reactor. An approximation of Talbot's Equation for thermophoretic velocity allowed experimental measurements to be combined with thermophoretic sample data to give predictions of particle number concentration corresponding to the precise sampling locations. The combinations of particle size distributions and number concentrations provide powerful insights on particle nucleation and growth dynamics. 相似文献