Tracking of complex binaural images

Subjects were presented with an initially stationary binaural image formed by the fusion of two identical pulses, without interaural time difference (ITD), at the two ears. The image was then made to traverse the subject's auditory perceptual space by introducing ITD, varying linearly with time, under computer control. The direction of movement, i.e. towards the right or left ear, could be reversed by the listener, by pressing a button. Subjects were requested to keep the image central, by pressing the button when they judged that deviation from subjective centre had occurred. Experiments of this type can be considered as analogous to Békésy audiometry, where the subject automatically traces his threshold of hearing, in that here the listener traces out his auditory perceptual centre as it varies with time. Hence, equivalent analyses to those employed for Békésy audiometry are possible. Subsequent to the initial part of the experiment, an additional pulse was added to one channel, preceding the original pulse, to form a pulse pair. The monaural masking of the original pulse by this additional pulse thus acts to shift the pre-existing binaural image. The effect of varying the amplitude and onset time of the masking pulse, relative to the original pulse, on the Békésy-type trace was examined.     

Six of One, Half a Dozen of the Other: Problems With Working Fixed and Rotating Shifts.

This study examined the relationship between shift patterns and role stressors and strains, as well as the extent to which situational variables and individual variables mediate the relationship between shift patterns and strains. Using survey data from 397 Israeli nurses, the author found that nurses working fixed day (vs. rotating) shifts reported less strains, but more stressors. Individual and situational variables mediated the relationship between shift pattern and both affective commitment and intention to leave, respectively. Younger age and higher role ambiguity might account for fully rotating shift nurses' reports of intention to leave, and being an older, full-time employee with little role conflict and ambiguity might explain why fixed day (vs. rotating) shift nurses report greater affective commitment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Designing piles of variable stiffness

Soil Mechanics and Foundation Engineering -     

Total Antioxidative Capacity and Total Phenolic Levels in Pomegranate Husks Correlate to Several Postharvest Fruit Quality Parameters

The demand to extend the marketing period of pomegranates requires a better understanding of the processes occurring during postharvest storage. Among the important factors that limit the long-term storage of pomegranates are disorders occurring on the fruit husk: fungal decay, chilling injury, shrinkage due to weight loss, and husk scald, all leading to loss of visual quality. The aim of this study was to examine processes that taking place during storage, and to analyze the relationship between the total antioxidant capacity and total phenolics content of the husks and the development of husk disorders in seven accessions. While the level of total phenolics increased during storage, concomitantly with the color index, the level of punicalagin, the main polyphenol in the husks with the highest antioxidant activity, declined during storage. The content of titratable acidity was also reduced. Regression analysis indicates that fruit having a high antioxidant capacity, high total phenolics content, and high levels of punicalin in their husks have a better ability to resist fungal decay and weight loss, in addition to being less sensitive to husk scald. On the other hand, the results suggest that the development of most husk disorders is not correlated to the content of total soluble solids, titratable acidity, punicalagin, anthocyanin, or husk color. Nonetheless, poorly colored accessions were relatively more sensitive to chilling injury expressed as surface pitting, compared with the more colored accessions. The appearance of these chilling injury symptoms was not correlated to total phenolics or the antioxidant capacity.     

Lateralization of human temporal lobe epilepsy by 31P NMR spectroscopic imaging at 4.1 T

OBJECTIVE: To compare the phosphorous metabolite ratios in the mesial temporal lobe of healthy volunteers (n = 20) with the corresponding ratios in patients with temporal lobe epilepsy (n = 30) using 31P NMR spectroscopic imaging and to lateralize the seizure focus in temporal lobe epilepsy patients using various phosphorous metabolite ratios-phosphocreatine to inorganic phosphate (PCr/Pi), PCr to adenosine triphosphate (PCr/gamma-ATP), and (gamma-ATP/Pi)--and to compare with clinical lateralization results. METHODS: All 31P NMR spectroscopic imaging studies were performed on a high-field, 4.1 T, whole-body NMR spectroscopic imaging system using a 31P/1H double-tuned volume coil. RESULTS: We found an average reduction of 15% in the PCr/Pi and gamma-ATP/Pi ratios compared with the corresponding ratios in healthy volunteers in the entire mesial temporal lobe, and more than a 30% reduction in these two ratios in the anterior region of the epileptogenic mesial temporal lobe. These ratios were also reduced significantly in the ipsilateral lobe when compared with their corresponding values in the contralateral lobe. In patients we lateralized the seizure focus, based on these 31P NMR data, and compared the results with the clinical lateralization. The lateralization based on either the PCr/Pi or the gamma-ATP/Pi ratio yielded a correspondence of 70 to 73% with the final clinical lateralization. In the subgroup of patients (n = 9) that needed intracranial EEG for the presurgical lateralization because of inconclusive results from the noninvasive methods, a 78% correspondence was found with the 31P NMR-based lateralization, whereas MRI provided a correspondence of only 33%, and scalp EEG provided a correspondence of only 56%. CONCLUSIONS: These results suggest the utility of adding the 31P NMR method to the group of noninvasive modalities used for presurgical decision making in temporal lobe epilepsy patients.     

超滤-微滤膜过滤传质理论的研究进展

探讨了超滤-微滤膜过滤传质理论的研究状况,重点介绍了超滤-微滤膜过理论模型、非牛顿液体膜堵塞过滤以及动态过滤等常规过滤理论的研究进展,评述了超滤-微滤膜过滤传质机理的动态,指出了超滤-微滤膜过滤基本理论模型需进一步研究解决的问题.