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41.
An analytical expression has been obtained for the transient temperature distribution produced when the retina is irradiated by a high-intensity light source. The following factors are included in the analysis: (1) structurally the fundus consists of layers of material which have different physical properties, (2) absorption of energy from the light beam follows the Beer-Lambert law, (3) energy is absorbed in the sclera as well as in the pigment epithelium and choroid, (4) heat is removed from the fundus by blood circulating through the capillaries of the choroid, and (5) intensity of the light source may vary with time. Computed values indicate that absorption of energy in the sclera and removal of heat by convection are both important for longer irradiation times, which agrees with recent experimental observations. The asymptotic response to a train of pulses is presented also. 相似文献
42.
Eugene Kaplounovski 《电子设计技术》2006,13(12):118-118
本设计实例介绍了对某种旧设计的增强措施(参考资料1)。图1中的电路使用常开型单刀单掷按钮开关S1,它代替了原始设计要求的单刀双掷开关。您可以使用膜片开关来大大简化该器件的工业设计并增强它的人机控制特性。另外,该电路消除了流过未动作开关的电流,由此略微减少了工作模式中的泄漏电流。 相似文献
43.
Several classes of regular expressions for timed languages accepted by timed automata have been suggested in the literature. In this article we introduce balanced timed regular expressions with colored parentheses which are equivalent to timed automata, and, differently from existing definitions, do not refer to clock values, and do not use additional operations such as intersection and renaming. 相似文献
44.
During the 1989 Loma Prieta earthquake the Pajaro River levees near Watsonville, Calif., spread laterally at multiple locations. Four of these locations are discussed in this paper. At one location, an industrial facility was also damaged and a dispute arose as to whether lateral spreading of the adjacent levee was the cause. Stability analyses were made of the industrial site for conditions before, during, and after the earthquake. To confirm the findings, analyses were also made of three other nearby locations where the actual deformation was documented and the subsurface conditions are well defined. The calculated levee deformations at the four locations are quite consistent with the observed movements (up to 60 cm). This experience provides increased confidence in the methods of analysis described, for the characterized subsurface conditions, and the range of ground motions experienced. Additional analyses made using the more recently developed multilinear regression lateral-spreading model (e.g., Youd et al. in 1999) yielded inconsistent results. 相似文献
45.
This investigation was prompted by Asch's (1952) discussion of the personal and social significance of yielding to group pressure. For the person, yielding requires the inhibition of overt and perhaps implicit responses to objective situational requirements. For the group, malignant processes may arise and develop, unchecked by those members in whom goals of personal security predominate over group goals. In the present study, the view was taken that both meanings of yielding are assigned positive value in two separate ideologies concerning the group-individual relation. One of these is termed "conformity" and the other is "rugged individualism." In the study, group pressure was simulated by announcing bogus group judgments to small groups of Ss whose apparent task was to match one of three lines of variable length with a standard line. Questionnaires were used to measure variables, which were: the ideology of conformity (IC), the ideology of rugged individualism (RI), ethnocentrism (E), and authoritarianism (F). The questionnaires were administered to 91 college students, both day school and evening. It was found that the correlation with the F scale was .48 (P 相似文献
46.
Monica L. Fernndez-Quintero Eugene F. DeRose Scott A. Gabel Geoffrey A. Mueller Klaus R. Liedl 《International journal of molecular sciences》2022,23(10)
Variable domains of camelid antibodies (so-called nanobodies or VHH) are the smallest antibody fragments that retain complete functionality and therapeutic potential. Understanding of the nanobody-binding interface has become a pre-requisite for rational antibody design and engineering. The nanobody-binding interface consists of up to three hypervariable loops, known as the CDR loops. Here, we structurally and dynamically characterize the conformational diversity of an anti-GFP-binding nanobody by using molecular dynamics simulations in combination with experimentally derived data from nuclear magnetic resonance (NMR) spectroscopy. The NMR data contain both structural and dynamic information resolved at various timescales, which allows an assessment of the quality of protein MD simulations. Thus, in this study, we compared the ensembles for the anti-GFP-binding nanobody obtained from MD simulations with results from NMR. We find excellent agreement of the NOE-derived distance maps obtained from NMR and MD simulations and observe similar conformational spaces for the simulations with and without NOE time-averaged restraints. We also compare the measured and calculated order parameters and find generally good agreement for the motions observed in the ps–ns timescale, in particular for the CDR3 loop. Understanding of the CDR3 loop dynamics is especially critical for nanobodies, as this loop is typically critical for antigen recognition. 相似文献
47.
Chen G Palke D Zhongzang L Yeh H Vincent P Laramee RS Zhang E 《IEEE transactions on visualization and computer graphics》2011,17(12):1979-1988
Asymmetric tensor field visualization can provide important insight into fluid flows and solid deformations. Existing techniques for asymmetric tensor fields focus on the analysis, and simply use evenly-spaced hyperstreamlines on surfaces following eigenvectors and dual-eigenvectors in the tensor field. In this paper, we describe a hybrid visualization technique in which hyperstreamlines and elliptical glyphs are used in real and complex domains, respectively. This enables a more faithful representation of flow behaviors inside complex domains. In addition, we encode tensor magnitude, an important quantity in tensor field analysis, using the density of hyperstreamlines and sizes of glyphs. This allows colors to be used to encode other important tensor quantities. To facilitate quick visual exploration of the data from different viewpoints and at different resolutions, we employ an efficient image-space approach in which hyperstreamlines and glyphs are generated quickly in the image plane. The combination of these techniques leads to an efficient tensor field visualization system for domain scientists. We demonstrate the effectiveness of our visualization technique through applications to complex simulated engine fluid flow and earthquake deformation data. Feedback from domain expert scientists, who are also co-authors, is provided. 相似文献
48.
We present an algorithm for automatic spot localization for microarray images with rectangular spot and block packing. As an input, the algorithm requires only the common array design parameters: number of block rows and columns and number of spot rows and columns within each block. It proved to be robust with respect to different types of contamination and can tolerate a high percentage of the missing spots. The validity of the developed algorithm has been tested and confirmed using a large set of images of various designs from different microarray platforms. Comparison with academic and commercial packages has shown that for uncontaminated images our algorithm performs similarly, whereas for certain problematic images it outperforms the other packages.Patent pending. 相似文献
49.
Eugene Shi Guang Choo Erwin Peng Reshmi Rajendran Prashant Chandrasekharan Chang‐Tong Yang Jun Ding Kai‐Hsiang Chuang Junmin Xue 《Advanced functional materials》2013,23(4):496-505
This study proposes a new method to generate positive contrast in magnetic resonance imaging (MRI) using superparamagnetic contrast agents. Superparamagnetic nanostructures consisting of octahedron manganese ferrite nanoparticles embedded in spherical nanogels are fabricated using a bottom‐up approach. The composite nanoparticles are strongly magnetized in an external magnetic field and produce a unique NMR frequency shift in water protons, which can be demonstrated in MR spectroscopy and imaging to be different from the bulk pool. Moreover, the particles exhibit excellent colloidal stability in aqueous media and good cell biocompatibility. Hence, these particles are potentially useful as biomarkers by taking advantage of the positive contrast effects produced in MRI. 相似文献
50.
This article describes an existentially informed approach to conducting psychotherapy with individuals living with the human immunodeficiency virus (HIV) and acquired immune deficiency syndrome (AIDS). Uses of existential concepts to guide a holistic conceptualization of the individual and illuminate core existential concerns and dilemmas in confronting HIV-related challenges are delineated. Applications of existential ideas regarding psychotherapy process and technique in HIV-related psychotherapy also are illustrated. It is concluded that existential psychotherapy offers a conceptual framework that is especially well suited to the work of psychotherapy with individuals living with HIV disease, although the approach has received only limited attention in the HIV-related psychotherapy literature. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献