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971.
Powell MJ Hughes JR Bird NC Glasse C King TR 《IEEE transactions on medical imaging》1998,17(6):1080-1083
We propose a method for producing a truly seamless tiled image sensor from four identical subarrays, such that the resulting tiled image sensor has no missing pixels. Four standard amorphous silicon photodiode-TFT (thin film transistor) arrays are cut parallel to the bus-bars, in the space between the bus-bar and the preceding pixel electrode. The cut is done in such a way that it is adjacent to the pixel electrode on the active plate. The four subarrays are then rotated by 90 degrees, with respect to their neighbors, and butted together. In this way, the seam between each tile has no adjacent bus-bar, and it is possible to reproduce the pixel pitch between neighboring tiles, with an acceptable alignment tolerance of the tiles. We have demonstrated the feasibility of the method, with the aid of a small prototype, based on a 192 x 192 pixel array, with a 200-microm pitch. Some image processing is necessary to rotate the images back for display on a conventional display monitor. This can cause artefacts, in some fast moving scenes, in which case an alternative scheme, which uses two mirror image arrays, each rotated by 180 degrees, can be used. However, for static X-ray images and most images in dynamic medical X-ray applications this is not necessary and we can obtain good quality seamless images, free from any significant artefacts. 相似文献
972.
SL Hughes A Ulasevich FM Weaver W Henderson L Manheim JD Kubal F Bonarigo 《Canadian Metallurgical Quarterly》1997,32(4):415-432
OBJECTIVE: To examine the impact of home care on hospital days. DATA SOURCES: Search of automated databases covering 1964-1994 using the key words "home care," "hospice," and "healthcare for the elderly." Home care literature review references also were inspected for additional citations. STUDY SELECTION: Of 412 articles that examined impact on hospital use/cost, those dealing with generic home care that reported hospital admissions/cost and used a comparison group receiving customary care were selected (N = 20). STUDY DESIGN: A meta-analytic analysis used secondary data sources between 1967 and 1992. DATA EXTRACTION: Study characteristics that could have an impact on effect size (i.e., country of origin, study design, disease characteristics of study sample, and length of follow-up) were abstracted and coded to serve as independent variables. Available statistics on hospital days necessary to calculate an effect size were extracted. If necessary information was missing, the authors of the articles were contacted. METHODS: Effect sizes and homogeneity of variance measures were calculated using Dstat software, weighted for sample size. Overall effect sizes were compared by the study characteristics described above. PRINCIPAL FINDINGS: Effect sizes indicate a small to moderate positive impact of home care in reducing hospital days, ranging from 2.5 to 6 days (effect sizes of -.159 and -.379, respectively), depending on the inclusion of a large quasi-experimental study with a large treatment effect. When this outlier was removed from analysis, the effect size for studies that targeted terminally ill patients exclusively was homogeneous across study subcategories; however, the effect size of studies that targeted nonterminal patients was heterogeneous, indicating that unmeasured variables or interactions account for variability. CONCLUSION: Although effect sizes were small to moderate, the consistent pattern of reduced hospital days across a majority of studies suggests for the first time that home care has a significant impact on this costly outcome. 相似文献
973.
JP Lorenzo ME Csuka BA Derfus RA Gotoff GM McCarthy 《Canadian Metallurgical Quarterly》1997,24(1):184-186
CLOser is a new, one-step, qualitative anti-Helicobacter pylori immunoglobulin G test having the advantage of convenience and simplicity. We aimed to evaluate its diagnostic accuracy and to compare it with a quantitative enzyme-linked immunosorbent assay (ELISA) (HEL-pTEST II) in a study of 86 adult dyspeptic patients by using the results from histology and urease testing of gastric biopsies as a "gold standard." Forty-six patients were H. pylori positive. The sensitivities, specificities, and positive and negative predictive values were 95.7, 72.5, 80.0, and 93.5%, respectively, for CLOser and 93.5, 92.5, 93.5, and 92.5%, respectively, for HEL-pTEST II. The grade of the colored test bands in CLOser was correlated with antibody titers in HEL-pTEST II (r = 0.71; p < 0.001). The mean antibody titers were 13, 74, 186, and 328 U/ml for the negative, faint, thin, and thick bands, respectively, of CLOser. We concluded that the CLOser rapid serological test yielded sensitivity similar to that of the conventional ELISA. Although CLOser is not suitable for epidemiologic screening for H. pylori infection on account of lower specificity, it is particularly convenient and very easy to perform. Therefore, it may eventually become widely used in the office-based care of patients and lead to more cost-effective patient management decisions. 相似文献
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977.
为了改善光敏树脂的燃烧性能,通过添加不同粒径和含量的高氯酸铵(AP)作为氧化剂,利用3D技术打印出含能树脂药柱。考察了AP在光敏树脂中的分散性及燃烧性能。结果表明:粒径为5.28 μm的AP在光敏树脂中的分散性最好;打印成型的含能树脂药柱燃速最快,残渣率最小。与打印成型的纯树脂药柱相比,该药柱的燃速提高了14倍,残渣率降低了94.30%。随着AP的质量分数从10%增至50%,药柱燃烧性能明显改善;当AP的质量分数为50%时,含能树脂药柱的燃速最高,残渣率最小,分别为1.05 mm/s和1.10 %。差热分析表明,含粒径为5.28 μm的AP的含能树脂药柱温度峰值出现最早,放热量最高。 相似文献
978.
Lessa Kay Grunenfelder Garrett Milliron Steven Herrera Isaias Gallana Nicholas Yaraghi Nigel Hughes Kenneth Evans‐Lutterodt Pablo Zavattieri David Kisailus 《Advanced materials (Deerfield Beach, Fla.)》2018,30(9)
Ecological pressures and varied feeding behaviors in a multitude of organisms have necessitated the drive for adaptation. One such change is seen in the feeding appendages of stomatopods, a group of highly predatory marine crustaceans. Stomatopods include “spearers,” who ambush and snare soft bodied prey, and “smashers,” who bludgeon hard‐shelled prey with a heavily mineralized club. The regional substructural complexity of the stomatopod dactyl club from the smashing predator Odontodactylus scyllarus represents a model system in the study of impact tolerant biominerals. The club consists of a highly mineralized impact region, a characteristic Bouligand architecture (common to arthropods), and a unique section of the club, the striated region, composed of highly aligned sheets of mineralized fibers. Detailed ultrastructural investigations of the striated region within O. scyllarus and a related species of spearing stomatopod, Lysiosquillina maculate show consistent organization of mineral and organic, but distinct differences in macro‐scale architecture. Evidence is provided for the function and substructural exaptation of the striated region, which facilitated redeployment of a raptorial feeding appendage as a biological hammer. Moreover, given the need to accelerate underwater and “grab” or “smash” their prey, the spearer and smasher appendages are specifically designed with a significantly reduced drag force. 相似文献
979.
In this paper, laser melting deposition(LMD), a new advanced manufacture technology. While manufacturing a metal part by LMD process, if we could control the energy distribution in internal different areas such as cladding layer or that between cladding layer and the substrate with optimal process parameters, the probability of internal defects of parts can be reduced, and the mechanical properties of parts will be greatly improved. To address the problem that whether the part made by LMD has internal defects, in this paper we designed the orthogonal rotation experiments through selecting different process parameters. Then a Logistic Regression model was built based on the experiments data. The calculation result of the regression model was in good agreement with the result of authentication test. Therefore, this Logistic Regression model has important reference for selecting LMD process parameters. 相似文献
980.
目的 探究贵州不同品种桃果实附着的微生物菌群组成情况。方法 以镇远红桃、镇远艳红桃和玉屏黄桃为试材,利用高通量测序技术分析贵州不同品种桃果实微生物的多样性。结果 红桃的主要优势细菌属为泛菌属、鞘氨醇单孢菌属和假单胞菌属,优势真菌属为枝孢菌属、交链孢属和曲霉属;艳红桃的优势细菌属为拟杆菌属、布老特氏菌属和甲基杆菌属,优势真菌属为链核盘菌属、枝孢菌属和交链孢属;黄桃的优势细菌属为甲基杆菌属、鞘氨醇单孢菌属和棒状杆菌属,优势真菌属为枝孢菌属、链核盘菌属和交链孢属。此外,α多样性分析表明艳红桃的真菌多样性最高,而黄桃的真菌多样性次之;β多样性分析表明构成不同品种桃群落组成有明显差异,而黄桃与红桃的群落组成相似程度更高。结论 研究初步明确了贵州不同品种桃果实的微生物多样性,为不同品种桃果实的绿色生产和贮藏保鲜提供理论基础。 相似文献