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91.
一、ST公司在3G多模式的能力 ST公司在世界半导体市场排名第六,亚太地区排名第三,目前正在开发用于3GFDD/TDD,TDSCDMA和GSM/GPRS多模式移动系统的一系列平台。这些平台将会把应用开发和完全集成的基带,RF和协议堆栈子系统组合成一个整体。这会给移动手机开发商和制造商提供一种能适应长远发展目标的、能无缝地开发出最后可以用系统级芯片(SoC)来解决的、不同产品的能力。 相似文献
92.
We empirically examined S. H. Budman and A. S. Gurman's (see record 1984-04498-001) theoretical proposals concerning major differences in the value systems of long- vs. short-term therapists. Ss were 222 randomly selected licensed psychologists who indicated their preferred approach (short-term or long-term). Values were assessed with a scale designed for the study. Overall, results indicate that therapists who prefer a short-term approach are more likely to endorse the proposed values of the short-term therapist than are therapists who prefer a long-term approach. This finding held even after the authors controlled for the significant contributions of theoretical orientation and therapeutic practice variables. Specifically, short-term (vs. long-term) therapists believed more that psychological change could occur outside of therapy and that setting time limits would intensify the therapeutic work. Implications for the practice of brief therapy are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
Human differentiation on the basis of gender is a fundamental phenomenon that affects virtually every aspect of people's daily lives. This article presents the social cognitive theory of gender role development and functioning. It specifies how gender conceptions are constructed from the complex mix of experiences and how they operate in concert with motivational and self-regulatory mechanisms to guide gender-linked conduct throughout the life course. The theory integrates psychological and sociostructural determinants within a unified conceptual structure. In this theoretical perspective, gender conceptions and roles are the product of a broad network of social influences operating interdependently in a variety of societal subsystems. Human evolution provides bodily structures and biological potentialities that permit a range of possibilities rather than dictate a fixed type of gender differentiation. People contribute to their self-development and bring about social changes that define and structure gender relationships through their agentic actions within the interrelated systems of influence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
94.
H Chao ME Houston RS Hodges CM Kay BD Sykes MC Loewen PL Davies FD S?nnichsen 《Canadian Metallurgical Quarterly》1997,36(48):14652-14660
The most abundant isoform (HPLC-6) of type I antifreeze protein (AFP1) in winter flounder is a 37-amino-acid-long, alanine-rich, alpha-helical peptide, containing four Thr spaced 11 amino acids apart. It is generally assumed that HPLC-6 binds ice through a hydrogen-bonding match between the Thr and neighboring Asx residues to oxygens atoms on the {2021} plane of the ice lattice. The result is a lowering of the nonequilibrium freezing point below the melting point (thermal hysteresis). HPLC-6, and two variants in which the central two Thr were replaced with either Ser or Val, were synthesized. The Ser variant was virtually inactive, while only a minor loss of activity was observed in the Val variant. CD, ultracentrifugation, and NMR studies indicated no significant structural changes or aggregation of the variants compared to HPLC-6. These results call into question the role of hydrogen bonds and suggest a much more significant role for entropic effects and van der Waals interactions in binding AFP to ice. 相似文献
95.
Among the attempts to measure particles produced in the cold fusion of deuterium in palladium metal is the mass spectrometric observation of tritium. An experiment which has been reported in the popular press involves attaching a hollow Pd electrode to a vacuum chamber and measuring the tritium produced during electrolysis using a mass spectrometer. We present data demonstrating that mass 5 and 6, which could be mistaken for the ions DT+ and T2
+, can arise from ion-molecule reactions in the ionizer of the mass spectrometer giving the ions HD2
+ and D3
+. With H2 and D2 present in the vacuum chamber, there are at least eight reactions which lead to these triatomic species, and these may contribute to a complex time and pressure dependence of the signals. 相似文献
96.
Katrina M. Nordstrom Anne M. Belcher Gisela Epple Kay L. Greenfield James J. Leyden Amos B. Smith III 《Journal of chemical ecology》1989,15(2):629-639
The resident skin surface microflora of 12 male and three femaleSaguinus fuscicollis was studied. The suprapubic-circumgenital gland surface and the perirectal area were most heavily colonized (106–108 colony forming units/cm2), but high numbers of organisms were also present on the abdomen, the sternal gland surface, and palms and plantar surfaces. Bacteria were also recovered from hair clippings as well as from shaven skin surface, although at much lower densities (102–104 colony forming units/cm2). Coagulase negative staphylococci, gram-negative bacteria,Streptococcus species and coryneform bacteria were most dominant.Staphylococcus aureus and species ofBacillus were also present. Fungi, yeast, and dermatophytes were infrequently recovered or completely absent. The microbial flora of these tamarins appears to be closely associated with the secretions of the circumgenital scent gland and would therefore be ideally situated to participate in the generation or modification of chemical signals. 相似文献
97.
The influence of braided pattern on macrobenthic communities was studied in the Lower Drǒme River (France). The qualitative differences between embanked and braided sections are weak. The sessile species (for example Psychomyia pusilla) are more frequent in the embanked section whereas the drifting species (for example Baetis fuscatus) are more frequent in the braided section. The density of macroinvertebrates in the latter, especially in the secondary channels, is higher than in the embanked section, but the diversity remains low because the location of the channels changes at each extreme flood. 相似文献
98.
Thorsten Helbig Kay Unterer Christian Kulas Sergej Rempel Josef Hegger 《Beton- und Stahlbetonbau》2016,111(10):676-685
Pedestrian bridge made from carbon‐concrete in Albstadt‐Ebingen – First entirely carbon‐reinforced concrete bridge worldwide The bridge erected in Albstadt‐Ebingen in October 2015 is realized without any steel reinforcement or pre‐tensioning, making it the world's first entirely carbon‐reinforced concrete bicycle and pedestrian‐bridge. The trough section with material thicknesses of 70 mm (trough walls) and 90 mm (slab) respectively has been fabricated as monolithic pre‐cast element. With a span length of 15 m and a width of 3 m, the bridge‐deck requires no further coating and has a total weight of just 14 tons (approximately 310 kg/m2); this is about 50 % of comparable conventional reinforced concrete bridge‐decks. Besides material and weight savings, an exceptionally long service life with minimal maintenance can be expected, as the steel corrosion that is typical in reinforced concrete structures can be entirely avoided. Since the use of carbon‐reinforced concrete (carbon concrete) is not yet approved in Germany, the client had to obtain approval based on individual cases (ZiE). 相似文献
99.
100.
Frederick Donald E.; Rojas-Líbano Daniel; Scott Meagen; Kay Leslie M. 《Canadian Metallurgical Quarterly》2011,125(4):588
To elucidate the cognitive structures of animals, neuroscientists use several behavioral tasks. Therefore, it is imperative to have a firm understanding of each task's behavioral parameters in order to parse out possible task effects. We compare two operant discrimination tasks (Go/No-Go: GNG; Two-Alternative Choice: TAC) that are commonly used in olfactory research. Past research has suggested that solving the two tasks requires divergent cognitive strategies. One hypothesis is that the two tasks differ in how an animal optimizes reward rate by means of a speed–accuracy trade-off (SAT). If this is true, then changing tasks could give researchers an additional tool to understand animal cognition. However, no study has systematically analyzed the two tasks in parallel using odor stimuli. Using standardized training protocols, we test GNG and TAC in parallel. Our protocols allow us to isolate the stimulus sampling period from a general reaction time period. We find that the two tasks do not differ with regard to the stimulus sampling period and conclude that the two tasks do not differ in the amount of time it takes an animal to perform a discrimination. Instead, tasks differ in the time it takes to make an overt behavioral response, with GNG showing shorter periods than TAC. We also find no evidence of rats using either task-specific or intertrial interval-dependent SAT schema in order to optimize reward rate. We show that similarities between dependent variables, with the possible exception of response delay, appear to be under experimenter control. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献