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961.
36 5- and 9-yr-olds and undergraduates were compared in a successive tachistoscopic recognition task in which size of the 1st array and the interval between the 1st array and the 2nd single recognition-test stimulus were varied. For all age groups, accuracy was highest at an interval of 250-1000 msec. At this interval, 5-yr-olds equalled older Ss' accuracy on single-item arrays but showed a significant decrement with increases in array size above 1 item, and they were inferior to older Ss on multiple-stimulus arrays. Nine-yr-olds showed a significant decrement with increases above 2 items, and adults showed small, nonsignificant decrements with increases in array size. Results of the yes-no task confirm previous findings of pointing recognition tasks that demonstrated age differences in short-term memory capacity. It is concluded that the observed differences cannot be attributed to age differences in report interference or retrieval strategies; rather, they appear to be due primarily to age differences in encoding processes, although differences in storage cannot be ruled out. Both groups of children showed a drop in performance at a 3-sec interval, but this drop was attributed to an inability to maintain attention rather than to storage characteristics. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
962.
One hundred eighteen psychiatric patients, each experiencing his or her first lifetime episode of psychosis, 125 of their first-degree relatives, and 155 normal subjects were assessed using the physical anhedonia, social anhedonia, and perceptual aberration scales of L. J. Chapman et al (1976; see also PA, Vol 62:3733). We hypothesized that psychotic subjects would obtain higher scores on these scales than their relatives and the controls, and we expected the group of relatives to score more deviantly than the normal controls. The physical anhedonia and social anhedonia scales successfully differentiated the psychiatric patients from the relatives and the latter from the normal subjects. These findings testify to the construct validity of the scales and suggest that they tap a predisposition to psychosis. Unexpectedly, the relatives scored lower on the perceptual aberration scale than did the normal controls, perhaps because the relatives adopted a defensive response set. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
963.
Cognitive function decline is strictly related to age, resulting in the loss of the ability to perform daily behaviors and is a fundamental clinical neurodegeneration symptom. It has been proven that an adequate diet, comprehensive nutrition, and a healthy lifestyle may significantly inhibit neurodegenerative processes, improving cognitive functions. Therefore, intensive research has been conducted on cognitive-enhancing treatment for many years, especially with substances of natural origin. There are several intervention programs aimed at improving cognitive functions in elderly adults. Cognitive functions depend on body weight, food consumed daily, the quality of the intestinal microflora, and the supplements used. The effectiveness in the prevention of dementia is particularly high before the onset of the first symptoms. The impact of diet and nutrition on age-associated cognitive decline is becoming a growing field as a vital factor that may be easily modified, and the effects may be observed on an ongoing basis. The paper presents a review of the latest preclinical and clinical studies on the influence of natural antioxidants on cognitive functions, with particular emphasis on neurodegenerative diseases. Nevertheless, despite the promising research results in animal models, the clinical application of natural compounds will only be possible after solving a few challenges.  相似文献   
964.
The interactions of G–quadruplexes of different topologies with highly fluorescent 9-methoxyluminarine ligand 9-MeLM were investigated by fluorescence and circular dichroism spectroscopy. The results showed that 9-methoxyluminarine was able to interact and did not destabilize any investigated molecular targets. The studied compound was selectively quenched by parallel c-MYC G-quadruplex DNA, whereas hybrid and antiparallel G4 topology caused only a negligible decrease in the fluorescence of the ligand. A high decrease of fluorescence of the ligand after binding with c-MYC G-quadruplex suggests that this molecule can be used as a selective probe for parallel G-quadruplexes.  相似文献   
965.
The overall objective of this study was to develop a decontamination method against microorganisms in cardamom (Elettaria cardamomum (L.) Maton) seeds using ozone as a decontaminating agent. Ozone treatment was conducted 3 times, at 24‐h intervals, and the parameters of the process were determined assuring the least possible losses of biologically active substances (essential oils and polyphenols): ozone concentration 160 to 165.0 g/m3; flow rate 0.1 L/min; pressure 0.5 atm; time 30 min. After each step of decontamination, the microbiological profile of the cardamom seeds was studied, and the contaminating microflora was identified. Next to the microbiological profile, the total polyphenol content (TPC), composition of essential oils, free radical‐scavenging capacity, total antioxidant capacity, ferric‐reducing antioxidant power (FRAP), and LC–MS polyphenol analysis were determined. This study shows that extract from cardamom seeds after ozone treatment is characterized by a better radical scavenging activity (IC50 = 24.18 ± 0.04 mg/mL) than the control sample (IC50 = 31.94 ± 0.05 mg/mL). The extract from cardamom seeds after ozone treatment showed an improved FRAP activity as well (613.64 ± 49.79 mmol TE/g compared to 480.29 ± 30.91 mmol TE/g of control sample). The TPC and the total antioxidant capacity were negatively affected, respectively, 41.2% and 16.2%, compared to the control sample.  相似文献   
966.
The electrophoretic deposition (EPD) method has been adapted for the deposition of ceramic green bodies from aqueous nanodispersions of alumina, yttria, yttrium aluminium garnet and lutetium aluminium garnet. These materials have been selected, since they are promising candidates for optically transparent ceramics. Films as well as cylindrical bodies have been successfully prepared by application of pulsed direct current (pDC) EPD. To guarantee constant deposition yield during pDC, a variant with variable pulse widths and pulse heights has been developed. The obtained green bodies were studied by surface area analysis, scanning electron microscopy, optical transmittance measurements, determination of pycnometric density and sintering behaviour. The effect of colloid-chemical dispersion properties on green and sintered ceramics is discussed as well. The green ceramics received are nanoporous and dense, providing excellent properties for further processing under mild conditions to optical materials. For comparison, EPD-formed green bodies were either processed directly to ceramic bodies or after additional compacting by hot-pressing in a piston-cylinder apparatus.  相似文献   
967.
The Minnesota Criminal Gang Pointer File database and GangNet database were established by law enforcement agencies as tools to monitor alleged gang members and reduce criminal gang activity. Law enforcement agencies have traditionally used gang databases to ensure public safety in the communities they serve. St Paul community members have raised concerns regarding the use of gang databases and the impact this has had, and continues to have, on those who have been mislabeled as gang members or are no longer part of a gang. In response to these community concerns, this report was compiled to highlight the various issues with the implementation, documentation, and use of Minnesota Criminal Gang Pointer File and GangNet databases, and offer recommendations for change.  相似文献   
968.
In recent years, there has been growing interest in the influence of sprouts on health. Fruit and vegetables are the main sources of organic acids for humans; however, little is yet known about organic acids in sprouts. In this study, the selection of the optimal parameters for extraction of organic acids from fresh, edible sprouts is reported. Two extraction techniques: microwave-assisted (MAE) and ultrasound-assisted were compared. The experimental conditions were optimized in terms of extraction time, temperature, and composition of extraction solution. To determine the influence of time and temperature of extraction or sample cooling, solvents used for extraction, on the analytical signal in isotachophoretic separation, the methods of experimental planning fractional factorial design: 3k?1 were used (three factor, three-level design). The optimal conditions for extraction of organic acids from radish sprouts were MAE, 90 °C; 18 min; and 0.01 M NaOH as a solvent.  相似文献   
969.
In this study, major types of flavonoids in 7‐day sprouts of five common buckwheat cultivars grown in Poland (Hruszowska, Kora, Panda, Luba and Emka) and wild tartary buckwheat were investigated. Results demonstrated that sprouts of common buckwheat cultivars and wild tartary buckwheat contained both known and a newly discovered flavonol: quercetin 3‐O‐galactosyl‐rhamnoside. An exceptionally high content of this flavonoid was found in cotyledons of wild tartary buckwheat (30.79 ± 0.14 mg g?1 DW), exceeding about 10 times level of rutin (3.16 ± 0.07 mg g?1 DW). The results are not consistent with the data published so far on the content of flavonoids in sprouts of tartary buckwheat. Higher levels of flavonoids were measured in cotyledons than in hypocotyls with the exception of anthocyanins, which were present in higher amounts in hypocotyls. Cotyledons of common buckwheat sprouts were rich in C‐glycosides of luteolin and apigenin, the total content of which exceeded ca. 5 times the concentration of rutin.  相似文献   
970.
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