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排序方式: 共有214条查询结果,搜索用时 31 毫秒
31.
32.
This paper presents a mathematical model that was developed specifically to calculate the produced shaded and sunlit areas in a circular courtyard geometry. It examines the interaction taking place between the sun at any time throughout the year and a circular courtyard form with any dimensions and proportions in any place on the earth. This model was included in a new computer program, which allowed detailed investigation to be undertaken into the effect of circular courtyard proportions on the generated wall and floor exposed and shaded areas. The results showed that changing the form's proportions significantly influences the shading or exposure potential of the internal courtyard envelope. 相似文献
33.
Moreno Jacqueline; Silverman Wendy K.; Saavedra Lissette M.; Phares Vicky 《Canadian Metallurgical Quarterly》2008,22(6):915
We examined the comparability between mothers' and fathers' ratings in the assessment of their child's anxiety symptoms. The sample consisted of 78 youth (6 to 17 years) and their mothers and fathers who presented to a childhood anxiety disorders specialty research clinic. Using intraclass correlation coefficients, mother?father agreement of their child's anxiety symptoms was found to be moderate. Mean differences between mothers' and fathers' ratings of their child's anxiety were not significantly different. Both maternal and paternal self-ratings of psychopathology predicted respective ratings of their child's anxiety. Although either mothers or fathers can provide useful information, use of multiple informants is encouraged, especially when parental psychopathology is present. Additional implications and suggestions for future research are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
34.
This study examined (a) the relationships between posttraumatic stress disorder (PTSD) symptom clusters and marital intimacy among Israeli war veterans and (b) the role of self-disclosure and verbal violence in mediating the effects of PTSD avoidance and hyperarousal symptoms on marital intimacy. The sample consisted of 219 participants divided into 2 groups: ex-prisoners of war (ex-POWs; N = 125) and a comparison group of veterans who fought in the same war but were not held in captivity (N = 94). Ex-POWs displayed higher levels of PTSD symptoms and verbal violence and lower levels of self-disclosure than did controls. Although ex-POWs and controls did not differ in level of marital intimacy, they did, however, present a different pattern of relationships between PTSD clusters and intimacy. In ex-POWs, self-disclosure mediated the relations between PTSD avoidance and marital intimacy. Verbal aggression was also found via indirect effect of hyperarousal on marital intimacy. The results point to the importance of self-disclosure and verbal violence as interpersonal mechanisms for the relations between posttraumatic symptoms on marital intimacy of ex-POWs. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
35.
Amalia H. Megarioti Cecilia Primo George C. Kapetanakis Alexandros Athanasopoulos Vicky Sophianopoulou Bruno Andr Christos Gournas 《International journal of molecular sciences》2021,22(19)
Selective endocytosis followed by degradation is a major mechanism for downregulating plasma membrane transporters in response to specific environmental cues. In Saccharomyces cerevisiae, this endocytosis is promoted by ubiquitylation catalyzed by the Rsp5 ubiquitin-ligase, targeted to transporters via adaptors of the alpha-arrestin family. However, the molecular mechanisms of this targeting and their control according to conditions remain incompletely understood. In this work, we dissect the molecular mechanisms eliciting the endocytosis of Can1, the arginine permease, in response to cycloheximide-induced TORC1 hyperactivation. We show that cycloheximide promotes Rsp5-dependent Can1 ubiquitylation and endocytosis in a manner dependent on the Bul1/2 alpha-arrestins. Also crucial for this downregulation is a short acidic patch sequence in the N-terminus of Can1 likely acting as a binding site for Bul1/2. The previously reported inhibition by cycloheximide of transporter recycling, from the trans-Golgi network to the plasma membrane, seems to additionally contribute to efficient Can1 downregulation. Our results also indicate that, contrary to the previously described substrate-transport elicited Can1 endocytosis mediated by the Art1 alpha-arrestin, Bul1/2-mediated Can1 ubiquitylation occurs independently of the conformation of the transporter. This study provides further insights into how distinct alpha-arrestins control the ubiquitin-dependent downregulation of a specific amino acid transporter under different conditions. 相似文献
36.
MehulB. Thathagar Jurriaan Beckers Gadi Rothenberg 《Advanced Synthesis \u0026amp; Catalysis》2003,345(8):979-985
Quantum dots (2–5 nm) of copper and copper/palladium mixtures are found to be good catalysts for Suzuki cross‐coupling. The catalysts are applicable to a wide range of iodo‐ and bromoaryl substrates, and give moderate yields using chloroaryl substrates. Cluster activity and stability is found to depend strongly on the preparation method and the reaction conditions. The mechanism of cluster deactivation and the sensitivity of the cluster‐catalysed reaction to substituent effects are studied and discussed. 相似文献
37.
Sudip Mukhopadhyay Gadi Rothenberg Yoel Sasson 《Advanced Synthesis \u0026amp; Catalysis》2001,343(3):274-278
Reductive homocoupling of chlorobenzenes to the respective biphenyls affords high yields (93–95%), in the presence of catalytic PEG‐400 and 0.4 mol % of a recycleable, heterogeneous trimetallic catalyst (4% Pd, 1% Pt, and 5% Bi on carbon). The competing reduction process is minimized. The catalytic cycle is completed using hydrogen gas, or formate + water or zinc + water mixtures, which generate dihydrogen in situ. Primary kinetic data and some process parameters are studied. The roles of the Pd, Pt, and Bi, different reducing agents, and the phase‐transfer agent are discussed. The reaction mechanism is proposed to depend on the relative concentration of hydride species in the immediate vicinity of the palladium metal. 相似文献
38.
Guy M. Holt Lauren J. Owen Sophie Till Yanying Cheng Vicky A. Grant Charlotte J. Harden 《Critical reviews in food science and nutrition》2017,57(16):3577-3582
Ratings of appetite are commonly used to assess appetite modification following an intervention. Subjectively rated appetite is a widely employed proxy measure for energy intake (EI), measurement of which requires greater time and resources. However, the validity of appetite as a reliable predictor of EI has not yet been reviewed systematically. This literature search identified studies that quantified both appetite ratings and EI. Outcomes were predefined as: (1) agreement between self-reported appetite scores and EI; (2) no agreement between self-reported appetitescores and EI. The presence of direct statistical comparison between the endpoints, intervention type and study population were also recorded. 462 papers were included in this review. Appetite scores failed to correspond with EI in 51.3% of the total studies. Only 6% of all studies evaluated here reported a direct statistical comparison between appetite scores and EI. χ2 analysis demonstrated that any relationship between EI and appetite was independent of study type stratification by age, gender or sample size. The very substantive corpus reviewed allows us to conclude that self-reported appetite ratings of appetite do not reliably predict EI. Caution should be exercised when drawing conclusions based from self-reported appetite scores in relation to prospective EI. 相似文献
39.
Biomimetically synthesized silica and conductive activated carbon nanofibers (CNFs) are used in a synergistic manner for the development of a novel electrochemical biosensor system. Poly(L-lysine) templated silica grows and encapsulates the CNF-immobilized enzyme generating a highly stabilizing nanostructured environment for the underlying protein. Concurrently, CNFs provide both the required surface area for the high-capacity enzyme immobilization required in biosensors as well as direct electron transfer to the inner platinum transducer. As a result, this silica/nanofiber superstructure is an ideal architecture for the development of electrochemical biosensor systems that can withstand exposure to extreme operational conditions, such as high temperatures or the presence of proteases. Acetylcholine esterase is used as the model catalyst and with the aid of spectroscopic data it is shown that the observed high operational stability of the biosensor is due to the direct interaction of the protein with the silica backbone, as well as due to the nanostructured enzyme confinement. 相似文献
40.
The sweetpotato weevil, Cylas formicarius (Fabricius) (Coleoptera: Brentidae), is the most serious pest of sweetpotato around the world, damaging sweetpotatoes in the field and in storage, as well as being a quarantine pest. Because the larval period is spent within vines or tubers, and the adults are nocturnal, chemical control frequently is not effective. In addition, there are few natural enemies, and pheromone-based trapping does not appear to reduce the damage level. In the present study, we evaluated a number of parameters that affect pheromone-based trap catch, including trap design, trap size, trap color, and height at which the traps are placed. Pherocon unitraps caught higher numbers than ground, funnel water, or delta traps. Medium-sized traps (13?×?17.5 cm) were more effective than larger or smaller traps. In a color-choice test, C. formicarius preferred red over gray, brown, blue, white, yellow, black, or red traps; light red was more attractive than other shades of red. Maximum catches were obtained when the traps were set 50 cm above the crop canopy. Light-red unitraps with pheromone lures caught more adults than identical traps without lures, suggesting that C. formicarius is influenced by both visual and olfactory cues. Pheromone-baited light-red unitraps, 13?×?17.5 cm, installed 50 cm above the crop canopy, were the most effective at catching C. formicarius adults, and they appear to have the greatest potential for use in trap-and-kill strategies and eradication programs. 相似文献