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131.
The genomic distance problem in the Hannenhalli–Pevzner (HP) theory is the following: Given two genomes whose chromosomes are linear, calculate the minimum number of translocations, fusions, fissions and inversions that transform one genome into the other. This paper presents a new distance formula based on a simple tree structure that captures all the delicate features of this problem in a unifying way, and a linear time algorithm for computing this distance. 相似文献
132.
Julia Armesto Izabela Lubowiecka Celestino Ordóñez Fernando I. Rial 《Automation in Construction》2009,18(5):559-569
The aim of this paper is to present a methodology for the evaluation of historic timber structures, based on numerical modeling coupled with on site measurements. A method to measure the geometry of structural elements of a timber roof using a photogrammetric modeling procedure is described. In particular, we show the utility of photogrammetric based models when applied to structural analysis by directly introducing 3D geometry files in the preprocessing module of computational software based on the Finite Element Method. The 2D and 3D FEM models of the roof are considered to compare the simple and more complex modeling, and static and dynamic analyses are performed. Both models are prepared using the photogrammetric data. 相似文献
133.
Neiworth Julie J.; Johnson Elizabeth T.; Whillock Katherine; Greenberg Julia; Brown Vanessa 《Canadian Metallurgical Quarterly》2009,123(1):10
To address a controversy in the literature concerning whether monkeys show an aversion to inequity, individuals of a New World monkey species, cotton top tamarins (Saguinus oedipus) were tested in an offering task and in a bartering task. At issue was whether the monkeys rejected rewards because of a violation of expectancy of the preferred reward, or whether they rejected rewards because of a sensitivity to socially mediated inequity. The data from both tasks indicated that the subjects were more likely to reject when preferred rewards were presented, either because of another animal eating the reward (the social condition) or because of rewards being presented but inaccessible. The bartering task led to the only behavioral indication of aversion due specifically to social inequity, which was demonstrated when tamarins' sensitivity to the difference in rewards increased with exposure to other tamarins working to receive the preferred rewards. The results suggest that social inequity aversion will be assessed by tamarins, and possibly by other primates, only under conditions of limited resources and a requirement of work, which may make the situation a bit more competitive and thus drives attention toward both social and reward evaluation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
134.
Guang Yong Zou Julia Taleban Cindy Y. Huo 《Computational statistics & data analysis》2009,53(11):3755-3764
There has accumulated a large amount of literature on confidence interval construction involving lognormal data owing to the fact that many data in scientific inquiries may be approximated by this distribution. Procedures have usually been developed in a piecemeal fashion for a single mean, a single mean with excessive zeros, a difference between two means, and a difference between two differences (net health benefit). As an alternative, we present a general approach for all these cases that requires only confidence limits available in introductory texts. Simulation results confirm the validity of this approach. Examples arising from health economics are used to exemplify the methodology. 相似文献
135.
Malay Patra Gilles Gasser Dr. Antonio Pinto Klaus Merz Dr. Ingo Ott Prof. Dr. Julia E. Bandow Prof. Dr. Nils Metzler‐Nolte Prof. Dr. 《ChemMedChem》2009,4(11):1930-1938
The recent discovery of the natural product platensimycin as a new antibiotic lead structure has triggered the synthesis of numerous organic derivatives for structure–activity relationship studies. Herein, we describe the synthesis, characterization and biological evaluation of the first organometallic antibiotic inspired by platensimycin. Two bioorganometallic compounds containing (η6‐pentamethylbenzene)Cr(CO)3 ( 2 ) and (η6‐benzene)Cr(CO)3 ( 3 ), linked by an amide bond to the aromatic part of platensimycin, were synthesized. Their antibiotic activities were tested against B. subtilis 168 (Gram positive) and E. coli W3110 (Gram negative) bacterial strains. Both compounds were found to be inactive against E. coli but derivative 2 inhibits B. subtilis growth at a moderate MIC value of 0.15 mM . To test the intrinsic toxicity of chromium, several chromium salts along with {η6‐(3‐pentamethylphenyl propionic acid)}Cr(CO)3 ( 5 ) and {η6‐(3‐phenyl propionic acid)}Cr(CO)3 ( 6 ) were tested against both bacterial strains. No activity was observed against E. coli for any of the compounds; B. subtilis growth was not inhibited by Cr(NO3)3 and only very weakly by 5 , K2Cr2O7 and Na2CrO4 at MIC values of 0.5, 0.68 and 1.24 mM , respectively. Compounds 2 , 3 , 5 and 4 (the pure organic analogue of 2 ) show similar cytotoxicity against HeLa, HepG2 and HT‐29 mammalian cell lines. Furthermore, the cellular uptake and the intracellular distribution of compounds 2 , 3 and Cr(NO3)3 in B. subtilis were studied using atomic absorption spectroscopy to gain insight in to the possible cellular targets. Compound 2 was found to be readily taken up and distributed almost equally among cytosol, cell debris and cell membrane in B. subtilis. 相似文献
136.
Andreas Opitz Bernhard Ecker Julia Wagner Alexander Hinderhofer Frank Schreiber Jochen Manara Jens Pflaum Wolfgang Brütting 《Organic Electronics》2009,10(7):1259-1267
Blends of organic electron and hole conductive materials are widely used for ambipolar charge carrier transport and photovoltaic cells. An obvious choice for donor–acceptor blends are organic semiconducting materials in their hydrogenated and fluorinated form, since they combine potentially suitable electronic properties with structural compatibility of the two constituents. This study focuses on the structural, optical, and electrical properties of blends using hydrogenated copper-phthalocyanine (H16CuPc) in combination with its per-fluorinated version (F16CuPc). Using X-ray scattering, scanning force microscopy and optical absorption measurements we show that mixed crystalline films are obtained by co-evaporation of the two materials. Electrical transport measurements reveal a profound reduction of the current for bipolar charge injection in mixed films. We discuss the formation of self-trapped charge transfer excitons as possible explanation for this unexpected behaviour, which impedes the usability of this system in photovoltaic cells. 相似文献
137.
Jeffrey A. Cook Jing Sun Julia H. Buckland Ilya V. Kolmanovsky Huei Peng Jessy W. Grizzle 《Asian journal of control》2006,8(3):237-260
This paper surveys recent and historical publications on automotive powertrain control. Control‐oriented models of gasoline and diesel engines and their aftertreatment systems are reviewed, and challenging control problems for conventional engines, hybrid vehicles and fuel cell powertrains are discussed. Fundamentals are revisited and advancements are highlighted. A comprehensive list of references is provided. 相似文献
138.
Hay Julia L.; Milders Maarten M.; Sahraie Arash; Niedeggen Michael 《Canadian Metallurgical Quarterly》2006,32(4):885
Recent visual marking studies have shown that the carry-over of distractor inhibition can impair the ability of singletons to capture attention if the singleton and distractors share features. The current study extends this finding to first-order motion targets and distractors, clearly separated in time by a visual cue (the letter X). Target motion discrimination was significantly impaired, a result attributed to the carry-over of distractor inhibition. Increasing the difficulty of cue detection increased the motion target impairment, as distractor inhibition is thought to increase under demanding (high load) conditions in order to maximize selection efficiency. The apparent conflict with studies reporting reduced distractor inhibition under high load conditions was resolved by distinguishing between the effects of "cognitive" and "perceptual" load. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
139.
140.
The role of psychologists as health care providers and the parameters of reimbursement for health care services are timely and controversial issues. A landmark decision was reached in this controversy in the 1980 appeal of a Virginia suit by clinical psychologists in which the court ruled that Blue Shield's refusal to directly reimburse psychologists was a violation of antitrust law. Thus, the requirement that psychologists bill through physicians was not upheld. In recent years a specific aspect of this controversy involved psychologists' roles in potential national health insurance programs. A limited study (appearing in the "National Register of Health Services Providers in Psychology" 1976-1978) of clinical psychologists' attitudes toward national health insurance suggests that Congress and psychologists may have disparate views. In addition to favoring national health insurance, over 85% of psychologists surveyed responded that consumers would benefit from such a program with mental health coverage. Only 16% agreed that such a program would constitute a subsidy of the rich by the poor (Albee, 1977). Several areas of conflicting or confusing responses in this study may reflect legitimate reasons for concern by Congress regarding institution of national health insurance. Belief that providers would benefit from mental health coverage in a national health insurance program was shared by 80% of respondents. Ninety-five percent of respondents identified the inclusion or exclusion of clinical psychologists in such a national health insurance as affecting the future of the profession. Curiously, over 50% of respondents agreed that primary care physicians should be reimbursed for mental health services, although such physicians have received no formal training in psychological services. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献