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131.
Saccharomyces cerevisiae kre5delta mutants lack beta-1,6-glucan, a polymer required for proper cell wall assembly and architecture. A functional and cell biological analysis of Kre5p was conducted to further elucidate the role of this diverged protein glucosyltransferase-like protein in beta-1,6-glucan synthesis. Kre5p was found to be a primarily soluble N-glycoprotein of approximately 200 kDa, that localizes to the endoplasmic reticulum. The terminal phenotype of Kre5p-deficient cells was observed, and revealed a severe cell wall morphological defect. KRE6, encoding a glucanase-like protein, was identified as a multicopy suppressor of a temperature-sensitive kre5 allele, suggesting that these proteins may participate in a common beta-1,6-biosynthetic pathway. An analysis of truncated versions of Kre5p indicated that all major regions of the protein are required for viability. Finally, Candida albicans KRE5 was shown to partially restore growth to S. cerevisiae kre5delta cells, suggesting that these proteins are functionally related.  相似文献   
132.
133.
The free vibration of rectangular laminated composite plates with arbitrary support conditions along the edges, internal line supports and discrete point supports are studied using the Rayleigh-Ritz method. Polynomial approximation functions are selected to satisfy all essential boundary conditions along the edges of the plate and to vanish along line supports parallel to the co-ordinate axes. Straight line supports at an angle from the co-ordinate axes and curved line supports are modeled by introducing several point supports along the line. Zero displacement constraints at the point support locations are enforced using the Lagrange multiplier technique. The plate constitutive equations are expressed in terms of stiffness invariants and the fundamental natural frequency is maximized by selecting the appropriate lay-up. Several examples are presented to illustrate the versatility of the approach and provide results not previously available. The influence of the number of plies in the laminate, lay-up, material properties and plate aspect ratios are investigated.  相似文献   
134.
The usual method to simulate vertical vibrations generated by road transport in laboratory is to use the average power spectral density. With this method, the distribution of the acceleration levels throughout the test is a Gaussian which does not conform to the reality of a transport. This study proposes an improvement of the classical method; this improvement permits to simulate the power spectral density and the distribution of acceleration levels by using a conventional device. The main idea of this method is to decompose the distribution of an actual road transport by using a sum of weighted Gaussians. Then, we apply the power spectral density with the root mean square acceleration (grms) level and duration corresponding to each Gaussian calculated from the weighted sum. We show that the weighting coefficients correspond to the time fraction of the test. Over the total duration of the test, we then retrieve the acceleration levels distribution of the actual transport. This new test method is experimentally validated with 2 examples of actual transports.  相似文献   
135.
Narrow bandgap n‐type organic semiconductors (n‐OS) have attracted great attention in recent years as acceptors in organic solar cells (OSCs), due to their easily tuned absorption and electronic energy levels in comparison with fullerene acceptors. Herein, a new n‐OS acceptor, Y5, with an electron‐deficient‐core‐based fused structure is designed and synthesized, which exhibits a strong absorption in the 600–900 nm region with an extinction coefficient of 1.24 × 105 cm?1, and an electron mobility of 2.11 × 10?4 cm2 V?1 s?1. By blending Y5 with three types of common medium‐bandgap polymers (J61, PBDB‐T, and TTFQx‐T1) as donors, all devices exhibit high short‐circuit current densities over 20 mA cm?2. As a result, the power conversion efficiency of the Y5‐based OSCs with J61, TTFQx‐T1, and PBDB‐T reaches 11.0%, 13.1%, and 14.1%, respectively. This indicates that Y5 is a universal and highly efficient n‐OS acceptor for applications in organic solar cells.  相似文献   
136.
Since the advent of online real estate database companies like Zillow, Trulia and Redfin, the problem of automatic estimation of market values for houses has received considerable attention. Several real estate websites provide such estimates using a proprietary formula. Although these estimates are often close to the actual sale prices, in some cases they are highly inaccurate. One of the key factors that affects the value of a house is its interior and exterior appearance, which is not considered in calculating automatic value estimates. In this paper, we evaluate the impact of visual characteristics of a house on its market value. Using deep convolutional neural networks on a large dataset of photos of home interiors and exteriors, we develop a method for estimating the luxury level of real estate photos. We also develop a novel framework for automated value assessment using the above photos in addition to home characteristics including size, offered price and number of bedrooms. Finally, by applying our proposed method for price estimation to a new dataset of real estate photos and metadata, we show that it outperforms Zillow’s estimates.  相似文献   
137.
Excess enthalpy data for the ternary system methane – ethylene – carbon dioxide was obtained utilizing an isothermal flow calorimeter. The measurements were made at three temperatures: 293.15, 305.15 and 313.15 K and pressures of 1.114, 1.520 and 3.445 MPa (11, 15 and 34 atm). The determination of excess enthalpies for the binary systems methane—ethylene, ethylene—carbon dioxide and methane—carbon dioxide has been reported in three preceeding articles, respectively: Gagné et al., 1985; Ba et al., 1979 and Barry et al., 1982a. The binary interaction coefficients kij obtained for these systems have been utilized as initial values for the optimization procedure leading to the kij for the ternary system. For the case of the ternary system studied in this investigation, two types of binary interaction coefficients kij have been determined from experimental data: kij independent of temperature and pressure and kij adjusted as function of temperature and pressure. Experimental data were compared with the predictions from Benedict—Webb—Rubin and Redlich—Kwong equations of state. In both cases, the coefficients kij dependent on temperature and pressure led to better prediction of excess enthalpies.  相似文献   
138.
Transportation policy and planning strategies, as well as Intelligent Transportation Systems (ITS), can all play important roles in decreasing pollution levels and their negative effects. Interestingly, limited effort has been devoted to exploring the potential of social network analysis in such context. Social networks provide direct feedback from people and, hence, potentially valuable information. A post telling how a person feels about pollution at a given time at a given location, could be useful to policy-makers, planners or environmentally-aware ITS designers. This work verifies the feasibility of sensing air pollution from social networks and of integrating such information with real sensors feeds, unveiling how people advertise such phenomenon, acting themselves as smart objects, and how online posts relate to true pollution levels. This work explores a new dimension in pollution sensing for the benefit of environmental and transportation research in future smart cities, confronting over 1,500,000 posts and pollution readings obtained from governmental on-the-field sensors over a one-year span.  相似文献   
139.
Théodule Ribot taught philosophy before obtaining 2 doctoral degrees from the Sorbonne in 1873: 1 about David Hartley and 1 about hereditary factors in psychology. Ribot wrote books on the topics of 19th-century British psychology (1870), 19th-century German psychology (1879), diseases of memory (1881), diseases of will (1883b), and diseases of personality (1885), among others. He founded the Revue Philosophique (Ribot, 1876b), had a chair created for him at the Collège de France (in 1888), helped organize the first French laboratory of experimental psychology (in 1889), and presided over the First International Congress of Psychology in Paris in 1889 (Ribot, 1889b). (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
140.
In order to study meiotic segregation of chromosome length polymorphism in yeast, we analysed the progeny of a cross involving two laboratory strains FL100trp and YNN295. Analysis of the parental strains led us to detect an important length polymorphism of chromosomes I and III in FL100trp. A reciprocal translocation involving 80 kb of the left arm of chromosome III and 45 kb of the right arm of chromosome I was shown to be the cause for the observed polymorphism in this strain. The characterization of the translocation breakpoints revealed the existence of a transposition hot-spot on chromosome I: the sequence of the translocation joints on chromosomes I and III suggests that the mechanism very likely involved homologous recombination between Ty2 transposable elements on each chromosome. Analysis of FL100, FL200 and FL100trp ura, which are related to FL100trp, shows that this reciprocal translocation is present in some of the strains of the FL series, whereas the parental strain FL100 does not carry the same rearrangement. We evidenced instead the duplication of 80 kb of chromosome III on chromosome I and a deletion of 45 kb of the right arm of chromosome I in this strain, indicating that secondary events might have taken place and that the strain currently named FL100 is not the common ancestor of the FL series. © 1998 John Wiley & Sons, Ltd.  相似文献   
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