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991.
992.
Herman Keith C.; Trotter Reid; Reinke Wendy M.; Ialongo Nicholas 《Canadian Metallurgical Quarterly》2011,58(3):321
The present study used a person-centered latent variable approach to classify types of perfectionism among 6th-grade African American children living in an urban setting. In particular, the authors were interested in determining whether an adaptive subtype could be found and validated against external criteria. The authors also attempted to identify any developmental precursors that could reliably differentiate the perfectionist subtypes. A social learning and competence framework was used to select potential 1st-grade risk and protective factors for future perfectionism profiles. Four classes best described the children's perfectionism scores in 6th grade. Three of these classes resembled the profiles most commonly seen in prior perfectionism research (Non-Critical/Adaptive, Critical/Maladaptive, and Non-Perfectionist). The fourth class, Non-Striving, was characterized by extremely low levels of reported personal standards. Sixth-grade correlates confirmed the distinctiveness of these classes. In particular, the Critical/Maladaptive and Non-Striving classes had higher rates of internalizing symptoms and disorders. Additionally, several 1st-grade predictors suggested unique developmental origins of these classes. The Critical/Maladaptive class was characterized by lower academic skills and elevated teacher-rated attention problems, hyperactivity, shyness, and peer rejection. The Non-Striving class had higher rates of family alcohol problems and lower levels of parent praise. Implications regarding the universal and culture-specific origins and effects of perfectionism are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
993.
994.
We have recorded the infrared absorption spectrum of pyrrole at 0.005 cm-1 spectral resolution using a Fourier transform interferometer. The rotational analysis of the symmetric out-of-plane C-H bend 22(1)0 fundamental band at 722.132993(5) cm-1 was performed, allowing 6760 lines to be assigned. These lines were fitted simultaneously to literature data on nu1 [A. Mellouki, R. Georges, M. Herman, D. L. Snavely, and S. Leytner, Chem. Phys. 220, 311-322 (1997)] and microwave lines [G. Wlodarczak, L. Martinache, J. Demaison, and B. P. Van Eijck, J. Mol. Spectrosc. 127, 200-208 (1988)]. A set of rotation parameters was determined for the ground state in Ir and IIIr representations, together with vibration-rotation constants for the v1 = 1 and v22 = 1 vibrational states. The fine structure in the strongest of the hot bands in that range was highlighted by division, from the experimental data, of the spectrum of the 22(1)0 band, computed using the vibration-rotation parameters. The rotational assignment of 930 lines in the strongest hot band was performed. The 22(1)024(1)1 vibrational assignment is proposed, leading to x22,24 = 1.90 cm-1. The transition dipole matrix element for the 22(1)0 band is estimated to || || = 2 x 10(-4) D. Copyright 1999 Academic Press. 相似文献
995.
van Strien Tatjana; Engels Rutger C. M. E.; van Staveren Wija; Herman C. Peter 《Canadian Metallurgical Quarterly》2006,18(1):89
In 4 empirical studies, E. Stice, M. Fisher, and M. R. Lowe (see record 2004-11653-006) calculated the correlations between some widely used dietary restraint scales and food intake. Failing to find substantial negative correlations, they concluded that these scales were invalid. The current article challenges this conclusion. For one thing, there is some evidence that restrained eaters do eat less than do unrestrained eaters under controlled experimental conditions favoring self-control. Dietary restraint is also associated with tendencies toward disinhibition under conditions favoring loss of self-control; such disinhibition often masks (but does not invalidate) the construct of dietary restraint. For these and other reasons, the assessment of food intake at a single eating episode may not capture overall dietary restriction. Finally, how much one eats does not necessarily indicate whether one has eaten less than one desired to eat. The authors suggest that the existing restraint scales do in fact validly assess restriction of food intake, albeit in a more complex fashion than is evident from simple correlations in single episodes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
BACKGROUND AND PURPOSE: The chronic phase of vasospasm after an aneurysmal subarachnoid hemorrhage may be mediated in part by early leukocyte-endothelial cell interactions. Ibuprofen is an anti-inflammatory agent that inhibits expression of certain cell adhesion molecules and therefore disrupts leukocyte-endothelial cell interactions. Its systemic administration, however, has dose-limiting side effects. We evaluated the effect of the periadventitial delivery of ibuprofen using controlled-release polymers in the rat femoral artery model of chronic posthemorrhagic vasospasm. METHODS: Before the animal studies, the release pharmacokinetics of the ibuprofen-loaded ethylene-vinyl acetate polymers were determined in vitro. Subsequently, the femoral arteries (n=266) of Fischer 344 rats (n=133) were enclosed in latex pouches bilaterally. In the toxicity study (n=15 rats), the animals were randomized into 5 dose groups in which 0%-, 10%-, 20%-, 30%-, or 50%-loaded ibuprofen polymers were evaluated. In the efficacy study, the animals were randomized into 5 time groups in which 50%-loaded ibuprofen polymers were inserted at 0 (n=58 rats), 6 (n=16), 12 (n=13), 24 (n=11), or 48 hours (n=12) after blood injection into the pouch. The rats were killed 12 days after blood exposure, at the time of maximal vasospasm in this model. Vasospasm was expressed as percent lumen patency. To evaluate the effect of ibuprofen on leukocyte migration, 8 rats were randomized into 2 groups. Macrophages and granulocytes were stained by immunohistochemistry with the use of a mouse OX-41 monoclonal antibody and counted in the periadventitial space 24 hours after blood exposure. RESULTS: In vitro pharmacokinetics showed that the 50%-loaded ibuprofen polymer released its total drug load over a 12-day period. In the toxicity study, a nonsignificant arterial vasodilatation with ibuprofen treatment was seen at higher doses, and no deleterious effects were noted on the vessel wall histologically. In the efficacy study, ibuprofen treatment resulted in significant vasospasm inhibition when treatment was initiated at 0 hour (73.7+/-4.9% versus 94.5+/-3.3% [mean+/-SEM percent lumen patency]; P<0.001) and 6 hours (69.2+/-5.7% versus 98.0+/-3.9%; P=0. 002) after blood exposure, but not at 12, 24, or 48 hours. Leukocyte immunohistochemistry showed that ibuprofen treatment resulted in significantly lower periadventitial macrophage and granulocyte counts of 25.0+/-3.9 cells per high-powered field compared with counts of 140.5+/-18.2 cells per high-powered field in the untreated vessels (P<0.001). CONCLUSIONS: The periadventitial, controlled release of ibuprofen from surgically implanted polymers significantly inhibits chronic posthemorrhagic vasospasm in this model when treatment is initiated within 6 hours of blood exposure. Vasospasm inhibition with ibuprofen correlates with a significant decrease in the number of macrophages and granulocytes in the periadventitial space. This study supports the hypothesis that inflammation mediates in part the chronic phase of posthemorrhagic vasospasm and suggests a potential alternative treatment for this condition. 相似文献
997.
Kimberly M. Bonger Dr. Sascha Hoogendoorn Chris J. van Koppen Dr. Cornelis M. Timmers Dr. Herman S. Overkleeft Prof. Gijsbert A. van der Marel Prof. 《ChemMedChem》2009,4(12):2098-2102
A series of homo‐ and heterodimeric compounds encompassing the follicle‐stimulating hormone receptor (FSHR) antagonist (R)‐ 1 and its inactive conformer (S)‐ 1 connected through ethylene glycol spacers of various lengths is described. Evaluation of these compounds reveals that dimeric compounds, with a spacer of sufficient length, bearing two active copies of the antagonist are more potent relative to dimeric compounds in which one of the active pharmacophores is replaced by an inactive conformer. Interestingly, the opposite trend is observed if a short spacer is used, indicating that these compounds may be valuable tools to study FSHR dimerization in greater detail. 相似文献
998.
Vladimir Kartashov Lars Henriksen Jon Herman Ulvensøen Benny Svardal Tore Svortdal Richard Berglind Gunnar Hedin 《Journal of the Society for Information Display》2009,17(7):581-587
Abstract— The image quality of a laser projection display based on a spatial light modulator with a deformable polymer layer (SLMDPL) has been improved. Bias diffraction has been reduced by two methods: (1) by filling the spacings between electrodes with SiO2 followed by deposition of a slightly conductive thin film and (2) by splitting electrodes. Both methods resulted in a contrast ratio of ?1200:1, which is significantly better than 50:1 measured for an earlier type of SLMDPL. Different methods of reducing the influence of electrical‐charge movement on the image quality have also been investigated. Substantial improvement has been achieved by using an alternating mode for signal voltage pulses, by increasing the conductivity of the gel layer, and by increasing the surface conductivity of the substrate between electrodes. Cross‐talk between neighboring pixels has been suppressed without a loss in the sensitivity by using a special layout of the electrodes in the SLMDPL. 相似文献
999.
Christian Russ Karlheinz Bock Mahmoud Rasras Ingrid De Wolf Guido Groeseneken Herman E. Maes 《Microelectronics Reliability》1999,39(11):1551
The triggering of grounded-gate nMOS transistors and field-oxide devices, essential for optimized protection design, is addressed by transmission line pulser (TLP)-pulsed emission microscopy. Current non-uniformity and instability effects in snapback operation under DC and TLP conditions are demonstrated. The comprehensive correlation of emission and electrical behavior allows an improved interpretation of device operation. Technological influences on the trigger uniformity are discussed. 相似文献
1000.
Yu Zhang Akhmad Herman Yuwono Jun Li John Wang 《Microporous and mesoporous materials》2008,110(2-3):242-249
Highly dispersed Au nanoparticles (NPs) of average size of 9–12 nm were successfully assembled in mesopores of titania thin films, through H2-reduction of . The well organized mesoporous nanostructure was characterized by using small-angle X-ray scattering, transmission electron microscopy, scanning electron microscopy, X-ray diffraction, secondary ion mass spectroscopy and UV–vis spectrophotometry. Au NPs embedded in the mesoporous nanostructure exhibited enhanced thermal stability, up to 450 °C, which is attributed to the spatial confinement effect of the mesopores with cubic configuration. An obvious surface plasmon resonance was observed at 570 nm in the UV–vis absorption spectra of Au NPs embedded in the mesoporous thin films. The red shift and broadening of plasmon band observed for Au NPs are accounted for by the interaction between Au NPs and mesoporous titania framework. The mesoporous TiO2/Au nanocomposite films show optically allowed direct transition of titania, where the incorporation of Au NPs evidently reduces the bandgap of titania. 相似文献