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121.
122.
Blascovich Jim; Mendes Wendy Berry; Hunter Sarah B.; Salomon Kristen 《Canadian Metallurgical Quarterly》1999,77(1):68
The authors conducted an experiment to test a theoretical explanation of social facilitation based on the biopsychosocial model of challenge and threat. Participants mastered 1 of 2 tasks and subsequently performed either the mastered (i.e., well-learned) or the unlearned task either alone or with an audience while cardiovascular responses were recorded. Cardiovascular responses of participants performing a well-learned task in the presence of others fit the challenge pattern (i.e., increased cardiac response and decreased vascular resistance), whereas cardiovascular responses of participants performing an unlearned task in the presence of others fit the threat pattern (i.e., increased cardiac response and increased vascular resistance), confirming the authors' hypotheses and the applicability of the biopsychosocial model of challenge and threat to explain these results. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
123.
Kenya Kani Joel Henzie
mer Dag Kathleen Wood Muhammad Iqbal Hyunsoo Lim Bo Jiang Carlos Salomon Alan E. Rowan Md. Shahriar A. Hossain Jongbeom Na Yusuke Yamauchi 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(35)
The electrochemical synthesis of mesoporous ruthenium (Ru) films using sacrificial self‐assembled block polymer micelles templates, and its electrochemical surface oxidation to RuOx is described. Unlike standard methods such as thermal oxidation, the electrochemical oxidation method described here retains the mesoporous structure. Ru oxide materials serve as high‐performance supercapacitor electrodes due to their excellent pseudocapacitive behavior. The mesoporous architectured film shows superior specific capacitance (467 F g?1 Ru) versus a nonporous Ru/RuOx electrode (28 F g?1 Ru) that is prepared via the same method but omitting the pore‐directing polymer. Ultrahigh surface area materials will play an essential role in increasing the capacitance of this class of energy storage devices because the pseudocapacitive redox reaction occurs on the surface of electrodes. 相似文献
124.
Foy N Stéphan E Vessières A Salomon E Heldt JM Huché M Jaouen G 《Chembiochem : a European journal of chemical biology》2003,4(6):494-503
A series of new derivatives of estradiol substituted at position 17alpha by various aryls has been synthesized. This was made possible by efficient activation methods for the addition of aryllithiums to the carbonyl group at position 17 of estrone by using tetramethylethylenediamine (TMEDA) or BF3 x OEt2. Their relative binding affinity (RBA) for the alpha and the beta forms of the estrogen receptor (ER) have been measured. All except one of the compounds synthesized had an RBA value of around 10 % which indicates a level of tolerance towards the bulky substituent at position 17. The lipophilicity values measured for these compounds are higher than that found for estradiol (E2). A study of their proliferative/antiproliferative effects was carried out on hormone-dependent (MCF7) and hormone-independent (MDA-MB231) breast cancer cell lines. It is interesting to note that all the compounds are estrogenic. The possibility of easily attaching an iodine at the end of a phenyl spacer opens up a route to new radiopharmaceuticals for use in radioimaging. 相似文献
125.
126.
Combinatorial property testing deals with the following relaxation of decision problems: Given a fixed property and an input
x, one wants to decide whether x satisfies the property or is “far” from satisfying it. The main focus of property testing is in identifying large families
of properties that can be tested with a certain number of queries to the input. In this paper we study the relation between
the space complexity of a language and its query complexity. Our main result is that for any space complexity s(n) ≤ log n there is a language with space complexity O(s(n)) and query complexity 2Ω(s(n)).
Our result has implications with respect to testing languages accepted by certain restricted machines. Alon et al. [FOCS 1999]
have shown that any regular language is testable with a constant number of queries. It is well known that any language in
space o(log log n) is regular, thus implying that such languages can be so tested. It was previously known that there are languages in space
O(log n) that are not testable with a constant number of queries and Newman [FOCS 2000] raised the question of closing the exponential
gap between these two results. A special case of our main result resolves this problem as it implies that there is a language
in space O(log log n) that is not testable with a constant number of queries. It was also previously known that the class of testable properties
cannot be extended to all context-free languages. We further show that one cannot even extend the family of testable languages
to the class of languages accepted by single counter machines.
相似文献
127.
Abstract. We consider a simple restriction of the PRAM model (called PPRAM), where the input is arbitrarily partitioned between a fixed
set of p processors and the shared memory is restricted to m cells. This model allows for investigation of the tradeoffs/ bottlenecks with respect to the communication bandwidth (modeled by the shared memory size m ) and the number of processors p . The model is quite simple and allows the design of optimal algorithms without losing the effect of communication bottlenecks.
We have focused on the PPRAM complexity of problems that have
(n) sequential solutions (where n is the input size), and where m ≤ p ≤ n . We show essentially tight time bounds (up to logarithmic factors) for several problems in this model such as summing, Boolean
threshold, routing, integer sorting, list reversal and k -selection. We get typically two sorts of complexity behaviors for these problems: One type is
(n/p + p/m) , which means that the time scales with the number of processors and with memory size (in appropriate ranges) but not with
both. The other is
(n/m) , which means that the running time does not scale with p and reflects a communication bottleneck (as long as m < p ). We are not aware of any problem whose complexity scales with both p and m (e.g.
). This might explain why in actual implementations one often fails to get p -scalability for p close to n . 相似文献
128.
Chri Rammer Per Lingvall Eva Salomon 《Journal of the science of food and agriculture》1997,73(3):329-336
The influence of cattle slurry applied to a silage crop was studied in three successive years. Each year, 40 t slurry ha-1 were applied in two equal applications. Unfertilised and mineral-fertilised field plots were used as controls. Before spreading, the slurry was contaminated with spores of Clostridium tyrobutyricum (103–104 g-1 FM). The fields were harvested two times a year, the yields were measured and the chemical composition and bacterial content of the crop were determined. The fresh material was chopped, ensiled without additives, and stored for 100 days before opening. The bacterial content of the soil surface and available N, P and K in soil were measured. Slurry did not seem to have any significance in a short-term perspective. Yield increase as an effect of slurry application was slight and inconsistent in comparison with the yield from unfertilised plots. The number of Clostridium or Bacillus spores in the soil surface was not significantly affected by the slurry application, nor was the number of detrimental organisms in harvested crop at ensiling. Nonetheless, in three of the four silages in which clostridial spores were estimated, numbers were higher in silage made from slurry-treated crops. © 1997 SCI. 相似文献
129.
Effects of pig and dairy slurry application on N and P leaching from crop rotations with spring cereals and forage leys 总被引:1,自引:0,他引:1
Helena Aronsson Jian Liu Erik Ekre Gunnar Torstensson Eva Salomon 《Nutrient Cycling in Agroecosystems》2014,98(3):281-293
Two crop rotations dominated by spring cereals and grass/clover leys on a clay soil were studied over 2 years with respect to nitrogen (N) and phosphorus (P) leaching associated with pig or dairy slurry application in April, June and October. Leaching losses of total N (TN), total P (TP), nitrate-N and dissolved reactive P (DRP) were determined in separately tile-drained field plots (four replicates). Mean annual DRP leaching after October application of dairy slurry (17 kg P ha?1) to growing grass/clover was 0.37 kg ha?1. It was significantly higher than after October application of pig slurry (13 kg ha?1) following spring cereals (0.16 kg ha?1) and than in the unfertilised control (0.07 kg P ha?1). The proportion of DRP in TP in drainage water from the grass/clover crop rotation (35 %) was higher than from the spring cereal rotation (25 %) and the control (14 %). The grass/clover rotation proved to be very robust with respect to N leaching, with mean TN leaching of 10.5 kg ha?1 year?1 compared with 19.2 kg ha?1 year?1 from the cereal crop rotation. Pig slurry application after cereals in October resulted in TN leaching of 25.7 kg ha?1 compared with 7.0 kg ha?1 year?1 after application to grass/clover in October and 19.1 kg ha?1 year?1 after application to spring cereals in April. In conclusion, these results show that crop rotations dominated by forage leys need special attention with respect to DRP leaching and that slurry application should be avoided during wet conditions or combined with methods to increase adsorption of P to soil particles. 相似文献
130.
L Salomon E Fontaine MF Gagnadoux M Broyer D Beurton 《Canadian Metallurgical Quarterly》1997,157(3):992-995
PURPOSE: We assessed the long-term efficacy of renal transplantation in children with posterior urethral valves. MATERIALS AND METHODS: We retrospectively compared the outcomes of renal transplantation in 66 children with posterior urethral valves and 116 with malformation uropathies (controls). RESULTS: Graft survival in the posterior urethral valves and control groups was 69 and 72% at 5 years, and 54 and 50% at 10 years, respectively (not statistically significant). A statistically significant increase in serum creatinine was noted at 10 years in children with posterior urethral valves but not in controls (p < 0.05). CONCLUSIONS: Renal transplantation in children with posterior urethral valves is not associated with a high rate of failure. However, long-term deterioration of graft function is likely related to lower urinary tract dysfunction. 相似文献