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1.
With youth participation in sports at an all-time high, youths have become more vulnerable to the silent epidemic of concussion. Psychologists should become aware of the alarming frequency of mild concussion and the subtle effects of concussion, which often go unnoticed or result in misdiagnosis. This article provides a basic survey of the research and literature on this topic, a simplified knowledge base for understanding updated assessment and management techniques, and a discussion of the important role psychologists can play in educating the public and their patients. Practitioners can become more aware of this developing practice opportunity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
The transmission model for anN-dimensional system is extended to handle additive noise and timing error. An orthogonal multiplex system operating in the presence of additive noise and channel introduced inter- and intra-symbol interference is analyzed. Error probabilities are derived and results are reported for carder sets comprising trigonometric product waveforms, Walsh functions, parabolic cylinder functions, and prolate spheroidal wave functions.  相似文献   
3.
Aberrant activation of the mitogen‐activated protein kinase (MAPK)‐mediated pathway components, RAF‐MEK‐ERK, is frequently observed in human cancers and clearly contributes to oncogenesis. As part of a project aimed at finding inhibitors of B‐Raf, a key player in the MAPK cascade, we originally identified a thiazole derivative endowed with high potency and selectivity, optimal in vitro ADME properties, and good pharmacokinetic profiles in rodents, but that suffers from elevated hERG inhibitory activity. An optimization program was thus undertaken, focused mainly on the elaboration of the R1 and R2 groups of the scaffold. This effort ultimately led to N‐(4‐{2‐(1‐cyclopropylpiperidin‐4‐yl)‐4‐[3‐(2,5‐difluorobenzenesulfonylamino)‐2‐fluorophenyl]thiazol‐5‐yl}‐pyridin‐2‐yl)acetamide ( 20 ), which maintains favorable in vitro and in vivo properties, but lacks hERG liability. Besides exhibiting potent antiproliferative activity against only cell lines bearing B‐Raf V600E or V600D mutations, compound 20 also intriguingly shows a weaker “paradoxical” activation of MEK in non‐mutant B‐Raf cells than other known B‐Raf inhibitors. It also demonstrates very good efficacy in vivo against the A375 xenograft melanoma model (tumor volume inhibition >90 % at 10 mg kg?1); it is therefore a suitable candidate for preclinical development.  相似文献   
4.
The wetting ability of water and of some biological liquids was measured on different biocompatible surfaces with and without different colloidal metals. Insoluble nanoparticles disperse in biological tissues enhance some properties, such as the interface adhesion between two surfaces, the X-ray contrast of medical images and the absorbed dose during radiotherapy treatments. The introduction of nanoparticles in the liquids generally improves the wetting ability and changes other properties of the solution, due to the different distribution of the adhesion forces, to the nature, morphology and concentration of the added nanoparticles. An investigation on the contact angle of the liquid drops, physiological liquids, including the human blood, placed on different substrates (polymers, ceramics and metals) with and without the use of metallic nanoparticles is presented, evaluated and discussed.  相似文献   
5.
The neural correlates of prospective retrieval mode, and the basis of the interaction between prospective memory (PM) and task switching, were examined using event-related brain potentials (ERPs). In two experiments individuals performed pure and mixed blocks of trials where they indicated whether or not a word was a noun or a verb or contained one or two vowels based upon a cue that was presented before the target stimulus. Experiment 1 revealed that prospective retrieval mode was associated with slow wave activity over the frontal and posterior regions of the scalp that differed in topography depending upon whether the PM cues were embedded in pure or mixed blocks of trials. This experiment also revealed that the neural correlates of task set configuration, but not cue encoding, were sensitive to PM load. These data indicate that PM load may effect task switching by influencing an individual's ability to maintain multiple task sets in working memory and to efficiently implement a given task set to guide task performance. Additionally, task switching may effect PM by influencing the degree to which individuals rely on stimulus-independent and stimulus-oriented processing to support the realization of delayed intentions. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
6.
This work presents the development of a method to measure the ethylene permeability of plastic films used in vegetable packaging, by exploiting the adsorption and desorption properties of a synthetic sodium zeolite. In order to establish the best conditions and requirements for the procedure, the ethylene adsorption and desorption by the zeolite was studied at different temperatures and partial pressures. The method was used to study the ethylene permeability of two common cling films (EVA and plasticized PVC) and shown to be both economical and accurate.  相似文献   
7.
Resonance light scattering (RLS) is a phenomenon due to an enhancement of the scattered light in close proximity to an absorption band. The effect is easily detectable in the case of strongly absorbing chromophores, which are able to interact, thus leading to large aggregates (Pasternack, R. F.; Collings, P. J. Science 1995, 269, 935). The measurement of absorption spectra from solutions containing such resonant systems can lead to misleading results. In this paper, a simple method is described to obtain absorption spectra of aggregated species with a fairly good correction of the scattering component. The RLS spectrum, obtained using a common spectrofluorimeter, is correlated to the extinction spectrum of the same sample, allowing for an estimation of the scattering contribution to the total extinction spectrum. The method has been successfully applied both on real samples containing aggregated chromophores, such as porphyrins, chlorophyll a and gold colloids, and by simulating extinction spectra.  相似文献   
8.
Manganese thiophosphate powders have been intercalated with sodium ions at two different intercalation times (150 min and 180 min) in order to evaluate the influence of this parameter on the dielectric properties of the obtained compounds labeled like Na2xMn1?xPS3. In particular, dielectric permittivity measures have been carried out as a function of temperature (80 K–350 K) and frequency (20 Hz to 1 MHz) and compared with each other and with those of the pure matrix and of the Na2xMn1?xPS3 compound corresponding to a 120 min intercalation time. Both investigated compounds show a dielectric response characterized by a loss peak at low temperatures, by a strong dispersion at low frequency and at not very high temperatures and by a crossover frequency showing an Arrhenius temperature dependence in agreement with what already observed in Na2xMn1?xPS3 (120 min). The results have been also discussed in terms of ac conductivity, Maxwell–Wagner–Sillar (MWS) polarization, electrode polarization and dc conductivity and all the above cited features have been attributed to the Na+ ions which are, by their nature, hopping charge carriers that behave like jumping dipoles in their alternate motions and simultaneously show conducting characteristics resulting from their extended hopping over many sites. This attribution allows us to classify the analyzed sodium compounds like hopping charge carrier systems in which a greater Na intercalation time translates into a decrease in the loss peak intensity and an increase in the activation energy associated to the crossover frequency.  相似文献   
9.
10.
The occurrence of both inter- and intrasymbol interference in a communications system utilizing orthogonal signals and memoryless correlation detection is described, and a system model is presented. A relationship between a bound on peak interference and time-bandwidth product for several well known orthogonal signal sets is reported.  相似文献   
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