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排序方式: 共有862条查询结果,搜索用时 15 毫秒
91.
Chen ZP Zhong LJ Nordon A Littlejohn D Holden M Fazenda M Harvey L McNeil B Faulkner J Morris J 《Analytical chemistry》2011,83(7):2655-2659
Large-scale commercial bioprocesses that manufacture biopharmaceutical products such as monoclonal antibodies generally involve multiple bioreactors operated in parallel. Spectra recorded during in situ monitoring of multiple bioreactors by multiplexed fiber-optic spectroscopies contain not only spectral information of the chemical constituents but also contributions resulting from differences in the optical properties of the probes. Spectra with variations induced by probe differences cannot be efficiently modeled by the commonly used multivariate linear calibration models or effectively removed by popular empirical preprocessing methods. In this study, for the first time, a calibration model is proposed for the analysis of complex spectral data sets arising from multiplexed probes. In the proposed calibration model, the spectral variations introduced by probe differences are explicitly modeled by introducing a multiplicative parameter for each optical probe, and then their detrimental effects are effectively mitigated through a "dual calibration" strategy. The performance of the proposed multiplex calibration model has been tested on two multiplexed spectral data sets (i.e., MIR data of ternary mixtures and NIR data of bioprocesses). Experimental results suggest that the proposed calibration model can effectively mitigate the detrimental effects of probe differences and hence provide much more accurate predictions than commonly used multivariate linear calibration models (such as PLS) with and without empirical data preprocessing methods such as orthogonal signal correction, standard normal variate, or multiplicative signal correction. 相似文献
92.
Seery Mark D.; Holman E. Alison; Silver Roxane Cohen 《Canadian Metallurgical Quarterly》2010,99(6):1025
Exposure to adverse life events typically predicts subsequent negative effects on mental health and well-being, such that more adversity predicts worse outcomes. However, adverse experiences may also foster subsequent resilience, with resulting advantages for mental health and well-being. In a multiyear longitudinal study of a national sample, people with a history of some lifetime adversity reported better mental health and well-being outcomes than not only people with a high history of adversity but also than people with no history of adversity. Specifically, U-shaped quadratic relationships indicated that a history of some but nonzero lifetime adversity predicted relatively lower global distress, lower self-rated functional impairment, fewer posttraumatic stress symptoms, and higher life satisfaction over time. Furthermore, people with some prior lifetime adversity were the least affected by recent adverse events. These results suggest that, in moderation, whatever does not kill us may indeed make us stronger. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
Six experiments used an illusory words paradigm to demonstrate that repetition blindness (RB) in orthographically similar words affects only the words' shared letters. Rapid serial visual presentation streams of words and word fragments allowed the unique letters of the 2nd critical word to combine with a subsequent fragment to create a word, as in rock shock ell. The illusory word shell was reported 2–3 times as frequently in RB conditions as in control conditions. Further experiments ruled out letter migration, contour summation, and differences in processing load as explanations for the results. These findings are inconsistent with current proposals that orthographic RB represents similarity inhibition or lexical competition or that it reflects problems with word-level token individuation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
94.
Shazia Bashir M. Shahid Rafique Wolfgang Husinsky Alison Hobro Bernhard Lendl 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(23-24):3606-3610
The phenomenon of nanohillock-like defect formation on the surfaces of CR-39 by ultra-short laser irradiation is investigated using an Atomic Force Microscope (AFM) and Raman Scattering. A polymer CR-39 target was exposed to Ti:sapphire 25-fs laser pulses with a central wavelength at 800 nm. Samples were irradiated for different laser fluences both in air and vacuum. Detailed surface topographical features of the bombarded samples were characterized by atomic force microscopy in contact mode in air at room temperature. AFM reveals that the growth of nanohillocks and their features are strongly dependent on the ambient condition, target position from focus, and irradiation fluence. The appearance of these nanohillocks in the range 1–20 nm in height and 10–90 nm in diameter are regarded as typical features for fast electronic processes (correlated with existence of hot electrons) and are explained on the basis of Coulomb explosion. These nanostructures due to localization of laser energy deposition in small areas provide a possible pathway from dense electronic excitation to atomic motion causing permanent structural modification which are well correlated to structural alterations, like crosslinking and chain scissions, inferred from Raman spectroscopy. 相似文献
95.
Alison Webb 《Network Security》2001,2001(9):11-14
The first of these articles, in Network Security’s July issue, described how Web servers work, and suggested that the security objectives for them might differ from those for standard applications. It also discussed some basic procedural controls. This article complements it with a more detailed look at the security features in Microsoft IIS, and then at how to apply those features together with operating system controls, to help secure the site. 相似文献
96.
Artificial rearing causes changes in maternal behavior and c-fos expression in juvenile female rats.
This study investigated the effects of early-rearing experiences on responsiveness to pups and on the pattern of c-fos activation in the brain of juvenile female rats. From Days 4 to 20, littermate females were reared with their mothers (MR) or artificially (AR). AR rats received minimal licking-like tactile stimulation (AR-min) or maximal stimulation (AR-max). On Day 20, rats were exposed to pups for 4 or 8 days, exposed to a playmate for 4 or 8 days, or left in isolation for 4 or 8 days. Compared with MR rats, pup-exposed AR rats engaged in less pup licking, and all AR rats showed significant reductions in c-fos immunoreactivity in the medial preoptic area and the parietal and piriform cortices. The AR-min group showed the greatest difference in Fos-lir compared with the MR groups. Possible mechanisms that mediate the effects of rearing on the development of neural circuits underlying maternal behavior are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
97.
Alison L Finlay 《Contact lens & anterior eye》2007,30(2):76-83
Binocular status can have an effect on the outcome of refractive surgery. Some accommodative deviations and anisometropia can be managed effectively. Fully accommodative esotropia has been successfully treated in young patients but the outcome can be less predictable in older patients. High anisometropes are usually unaffected by the change in aniseikonia following refractive surgery but there are exceptions. Failure to recognise and appropriately classify a binocular vision anomaly pre-surgically can result in symptoms that are difficult to manage post-operatively. Refractive surgery producing a binocular vision anomaly where there was none pre-operatively is less common. I present a review of the literature discussing the relationship between binocular vision anomalies and refractive surgery, illustrating the findings with published reports of successful and unsuccessful binocular postoperative outcomes. I argue that predicting the binocular outcome should be considered pre-operatively for every refractive surgery patient. 相似文献
98.
Boone Kyle Brauer; Lesser Ira M.; Miller Bruce L.; Wohl Marcy; Berman Nancy; Lee Alison; Palmer Barton; Back Carla 《Canadian Metallurgical Quarterly》1995,9(3):390
Neuropsychological evaluation of 73 older healthy, unmedicated outpatients with major depression and 110 controls suggested that relatively distinct cognitive profiles may correspond to the presence vs. severity of depression. Specifically, the presence of depression was associated with subtle weaknesses in visual memory and nonverbal intelligence, with sparing of verbal skills (verbal intelligence, language, and verbal memory), constructional ability, attention, information processing speed, and executive functions. In contrast, increasing severity of depression was associated with mild weaknesses, primarily in information-processing speed and executive skills, but was essentially unrelated to memory (verbal or visual), intelligence, language skills, constructional ability, or basic attention. Findings are discussed in terms of a possible state vs. trait model of depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
99.
100.
Wills Thomas Ashby; Yaeger Alison M.; Sandy James M. 《Canadian Metallurgical Quarterly》2003,17(1):24
This research examined the hypothesis that religiosity buffers the impact of life stress on adolescent substance use. Data were from a sample of 1,182 participants surveyed on 4 occasions between 7th grade (mean age = 12.4 years) and 10th grade. Religiosity was indexed by Jessor's Value on Religion Scale (R. Jessor & S. L. Jessor, 1977). Zero-order correlations showed religiosity inversely related to alcohol, tobacco, and marijuana use. Significant Life Events×Religiosity buffer interactions were found in cross-sectional analyses for tobacco, alcohol, and marijuana use. A latent growth analysis showed that religiosity reduced the impact of life stress on initial level of substance use and on rate of growth in substance use over time. Implications for further research on religiosity and substance use are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献