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51.
Working memory deficits have been identified in bipolar disorder, but there is evidence suggesting that these deficits may be markers for psychosis rather than affective disorder. The current study examined this issue by comparing two groups of individuals with bipolar disorder, one with psychotic features and one without psychotic features, with a group of normal controls. Working memory was conceptualized as a multicomponent system that includes auditory and visuospatial short-term stores, executive control processes, and an episodic buffer that allows for communication between short- and long-term memory stores (Baddeley & Logie, 1999). Results indicated that only executive control processes significantly differentiated the psychotic and nonpsychotic bipolar groups, although visuospatial working memory differentiated both bipolar groups from controls. The results support the idea that some aspects of working memory performance are markers for psychosis, while others may be more general markers for bipolar disorders. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
52.
Carbon fiber (CF)‐embedded acrylonitrile butadiene styrene polymer composites printed on the large‐scale printer at Oak Ridge National Laboratory were investigated by small‐angle neutron scattering to correlate the microstructure of the composites with their mechanical strength. The microstructure of the polymer domains and the alignment of CF were characterized across the interfaces between layers of the hot‐melt extruded material and were compared with CF‐free ABS. The small‐angle neutron scattering data show that the CF‐containing material displays strong anisotropic scatterings suggesting molecular alignment along the printing direction that is not present in the CF‐free ABS. Scattering data analysis across the interfacial layer revealed enhanced molecular alignment along the printing direction near the boundaries and inhomogeneous size distribution of polymer domains upon the addition of CF. We attribute the compromised strength across interfacial layers from CF‐containing material to this inhomogeneous size distribution which prevents effective lateral interaction between layers. POLYM. ENG. SCI., 59:E65–E70, 2019. © 2018 Society of Plastics Engineers  相似文献   
53.
Oxysterols (OHCs) are metabolic byproducts of cholesterol that are known to function as agonists of the Hedgehog (Hh) signaling pathway. Previously, we reported 23(S)‐hydroxycholesterol [23(S)‐OHC, 4 ] as a potent activator of Hh signaling with the ability to functionally differentiate mouse embryonic fibroblasts to an osteogenic fate. To obtain 23(S)‐OHC in quantities suitable for in vivo evaluation, we developed a revised synthetic route that decreases the number of steps and chromatographic purifications, and which also enhances the stereoselective nature of the synthesis. This new route also allows access to the C21 methyl group of the OHC scaffold, and several new analogues with varying stereochemistry at this location were evaluated for their ability to up‐regulate the Hh pathway.  相似文献   
54.
Reconstructive fire testing is an important tool used by fire investigators to determine the cause, origin, and progression of a particular fire. Accurate reconstruction of the fire requires the laboratory structure to be outfitted with materials that, in terms of contribution to fire growth, perform similarly to the original materials found at the fire scene. Therefore, a procedure was developed to enable fire investigators to select these replacement materials on the basis of a quantitative assessment of their relative fire performance. This procedure consists of gram‐scale and/or milligram‐scale standard testing accompanied by inverse numerical modeling of these tests, which is used to obtain relevant material properties. A numerical model composed of a detailed pyrolysis submodel and empirical flame heat feedback submodels, which were developed in this study, is subsequently employed to simulate the early stages of the Room Corner Test, which was selected to represent full‐scale material performance. The results of these simulations demonstrate that this procedure can successfully differentiate between fire growth propensities of several commercially available medium density fiberboards.  相似文献   
55.
Although many kinds of data can be used to guide instructional consultations, research comparing the efficacy of such data is scant, especially in engineering. In this study, multiple modes of assessment were used to evaluate the impact of consultations informed by different kinds of data. This study illuminates two key aspects of instructional consultations: (1) their efficacy varies depending on the kind of data used to guide them, with student feedback from a Small Group Instructional Diagnosis (SGID) having the largest positive impact, and (2) the instructional consultant plays a key role in helping both interpret the available data and identify strategies for improvement. These findings suggest three implications for practice: (1) whenever possible, SGID‐based consultations should be offered systematically and proactively for engineering faculty, (2) data for other kinds of consultations should be tailored to the needs of the individual instructor, and (3) instructional consultants should be available to collaborate with faculty to enhance their teaching, thereby building an engineering culture that actively supports teaching and learning.  相似文献   
56.
57.
The effect of electron-donating and electron-withdrawing side chains on the electronic properties of thieno[3,4-b]pyrazines and their corresponding homopolymers have been investigated. Contrary to common trends in polythiophene materials, the addition of electron-donating groups results in higher HOMO–LUMO energies in the monomers and higher Eg values in the resulting polymers. The use of electron-withdrawing groups, however, provides reduced HOMO–LUMO energies and lower Eg values. The application of electron-withdrawing functionalized thieno[3,4-b]pyrazines appears to be a promising new approach for the production of low Eg materials.  相似文献   
58.
Parkinson's disease (PD) is a neurodegenerative disorder in which loss of dopaminergic (DA) neurons (>50%) in the substantia nigra (SN) precedes most of the overt motor symptoms, making early diagnosis and treatment interventions difficult. Because PD has been associated with free radicals generated by nitric oxide, this study tested whether treatments of 7-nitroindazole (7NI), a nitric-oxide-synthase inhibitor, could reduce cognitive deficits that often emerge before overt motor symptoms in a presymptomatic rat model of PD. Rats were given intraperitoneal injections of 50 mg/kg 7NI (or vehicle) just before receiving bilateral, intrastriatal injections of the DA-toxin, 6-hydroxydopamine (6-OHDA). The rats were then given a battery of motor tasks, and their learning ability was assessed using a spatial reversal task in a water-T maze. Results indicate that 7NI treatments attenuate 6-OHDA-induced spatial learning deficits and protect against DA cell loss in the SN, suggesting that 7NI may have potential as an early, presymptomatic pharmacotherapy for PD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
59.
Recent research has suggested that each statement in a narrative text is understood by relating it to its causal antecedents and consequences and that the text as a whole is understood by finding a causal path linking its opening to its final outcome. C. R. Fletcher and C. P. Bloom (see record 1989-10829-001) have proposed that in order to accomplish this goal, while minimizing the number of times long-term memory has to be searched, readers focus their attention on the last clause of a narrative that has causal antecedents but no consequences in the preceding text. As a result, a statement that is followed by a causal antecedent should remain the focus of attention, while the same statement followed by a consequence should not. This prediction was tested and confirmed in three experiments which show that when a target statement is followed by a sentence that includes only causal antecedents (a) continuation sentences related to it are read more quickly, (b) target words drawn from it are easier to recognize, and (c) subject-generated continuations are more likely to be causally related to it. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
60.
This study was conducted to evaluate the effect of red-wine grape pomaces on the quality and sensory attributes of beef hamburger patties. Both phenolic content and antioxidant activity were assessed using Syrah, Merlot and Cabernet Sauvignon pomaces. Following the assessment, hamburger patties were prepared with Merlot pomace at 0%, 2% and 4% for the patty quality and sensory attributes. Grape seeds possessed significantly higher phenolics and antioxidant activities over the seedless pomace (P < 0.05), whereas no significant difference was found for phenolics and antioxidant activities within the seeds and seedless pomaces. The patty pH decreased as the pomace was added for 2% and 4%. Colour values (L*, a* and b*) of patties lowered as the pomace was added. Allo-Kramer shear force and hardness values increased while cooking yield decreased (P < 0.05) with the addition of pomace. No significant difference between control and Merlot patties was found for flavour, juiciness and colour, whereas lower sensory attributes were observed for texture, taste and overall acceptability. It is observed that the addition of fermented red-wine grape pomace provides hamburger patties with health promoting factors such as antioxidant and other functional components, but it also provided darker, sourer and lower cooking yield.  相似文献   
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