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61.
ABSTRACT

The review summarizes diverse knowledge about the problem of Linum usitatissimum L. response on photoperiod. Within this species, high genetic variability of the photosensitivity degree and influence of photoperiod on different plants characters were discovered. It was shown that in flax, earliness of flowering in long daylight is not strictly related to the low photosensitivity, and late genotypes with low photosensitivity can be found. In short daylight, various plant characters of different genotypes can be stable or display different reactions: increase or decrease their values. Also, the degree of photosensitivity does not have stable correlations with agronomic characters.  相似文献   
62.
The thermal unfolding of turkey gizzard smooth muscle myosin subfragment 1 (S1) and heavy meromyosin (HMM) in the absence of added nucleotides, in the presence of ADP, and in S1 or HMM ternary complexes with ADP and Pi analogs, orthovanadate (Vi), beryllium fluoride (BeFx), or aluminum fluoride (AlF4-), have been studied by differential scanning calorimetry (DSC). It has been shown that the formation of these ternary complexes causes significant structural changes in S1 or in the heads of HMM which are reflected in a pronounced increase of the protein thermal stability. The effect of BeFx was less distinct than that of AlF4- or Vi. Phosphorylation of regulatory light chains (RLC) in S1 or in HMM had practically no influence on these effects. In general, the changes caused by various Pi analogs in smooth muscle S1 or HMM were similar to those observed earlier with skeletal muscle S1 devoid of RLC. It is concluded that RLC and their phosphorylation do not significantly affect the character of structural changes induced in motor domains of the HMM heads by the formation of ternary complexes HMM--ADP--Vi, HMM--ADP--AlF4-, and HMM--ADP--BeFx--stable analogs of the intermediate states of the HMM ATPase reaction, HMM.ADP.Pi and HMM. ATP.  相似文献   
63.
Mental simulation provides a window on the future by enabling people to envision possibilities and develop plans for bringing those possibilities about. In moving oneself from a current situation toward an envisioned future one, the anticipation and management of emotions and the initiation and maintenance of problem-solving activities are fundamental tasks. In the program of research described in this article, mental simulation of the process for reaching a goal or of the dynamics of an unfolding stressful event produced progress in achieving those goals or resolving those events. Envisioning successful completion of a goal or resolution of a stressor—recommendations derived from the self-help literature—did not. Discussion centers on the characteristics of effective and ineffective mental simulations and their relation to self-regulatory processes. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
64.
Given the reputation that psychoanalytic theory is biased against women, this study investigated 2 questions: (a) How common is it that empirical studies of psychoanalytic theory use male as opposed to female participants? and (b) What is the success rate in predicting women's and men's behavior? The empirical study of psychoanalytic hypotheses is apparently a predominantly male endeavor involving predominantly male participants. A meta-analysis of 98 relevant articles demonstrated that studies using both genders reported stronger results with men than women. However, studies using one gender only reported comparable results for men and women. Author gender, date of publication, and type of outcome measure used were unrelated to outcome. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
65.
The correlation between chemical effects of some typical optical fiber coating formulations and adhesion to glass was studied by the use of laser spallation. The technique was able to show verifiable differences between dissimilar materials and demonstrated a good correlation to adhesion values determined by mechanical peel testing, and to pullout values measured on coated optical fiber. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 2459–2468, 2004  相似文献   
66.
This study compared performance of 15- to 17-month-old Ts65Dn mice to that of littermate controls on an automated sustained attention task in which the location, onset time, and duration of brief visual cues varied unpredictably. Ts65Dn mice committed more omission errors than controls, particularly on trials with the briefest cues. Videotape data revealed that the trisomic mice attended less than controls during the period before cue presentation and engaged in stereotypic jumping and grooming immediately after making an error. These findings reveal that Ts65Dn mice are impaired in sustaining attention and exhibit heightened reactivity to committing an error, and support the validity of this mouse model for studying Down syndrome and Alzheimer's disease. The attention task, coupled with the videotape analyses of task performance, provides a useful paradigm for studying attention and reactivity to errors in mice. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
67.
68.
Nusinsky I  Hardy AA 《Applied optics》2007,46(17):3510-3517
We investigate omnidirectional reflection from higher-order gaps in one-dimensional photonic crystals. Moreover, we present a designing criterion for omnidirectional reflection from several distinct gaps simultaneously, using only a single photonic crystal with a constant period. We show that for practical values of photonic crystals parameters, several relatively large omnidirectional gaps may be obtained. As an example, we demonstrate an omnidirectional reflector that exhibits two distinct wide omnidirectional ranges at near-infrared wavelengths. This omnidirectional reflector that operates in several ranges of wavelengths may have various potential applications.  相似文献   
69.
Thermal conductivity of thin silicon nanowires (1.4-8.3 nm) including the realistic crystalline structures and surface reconstruction effects is investigated using direct molecular dynamics simulations with Stillinger-Weber potential for Si-Si interactions. Thermal conductivity as a function of decreasing nanowire diameter shows an expected decrease due to increased surface scattering effects. However, at very small diameter (<1.5 nm), an increase in the thermal conductivity is observed, which is explained by the phonon confinement effect.  相似文献   
70.
Rare earth elements play a pivotal role in modern technologies, thereby driving an escalating demand for their procurement. To effectively extract these elements from aqueous solutions, it is imperative to explore innovative sorbent materials. In this context, a hydrogel sorbent material was developed by employing poly(vinyl alcohol) (PVA) and shungite—an economical, naturally occurring, easily processable, and sustainable material. This was achieved through the freezing–thawing method, employing sodium borate as a crosslinking agent. The physicochemical characteristics of the hydrogels were determined through scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FTIR), Brunauer–Emmett–Teller (BET) analysis, Zetasizer analysis, and elemental analysis. The shungite-incorporated PVA hydrogels displayed notable characteristics, including a substantial swelling capacity of 61% and a specific surface area of 32.8 m2/g. Most significantly, these hydrogels exhibited a remarkable affinity for La3+ ions, with an uptake ratio of 134 mg/g. This was followed by Nd3+, Dy3+, and Er3+ ions, which displayed uptake ratios of 79, 74, and 73 mg/g, respectively.  相似文献   
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