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981.
Nikolai G. Kalugin Irakli Kalichava Christopher Del Barga Juan G. Duque Stephen K. Doorn Aaron V. Gin 《Carbon》2010,48(12):3405-3411
We report on SEM, AFM, and Raman identification of non-planar several monolayer-thick graphene nanostructures with curved shapes. During mechanical exfoliation we obtained graphene flakes with nanowire/nanotube-like objects (diameters between 8 and 35 nm) with cross-sectional profile reminiscent of the Greek capital letter omega (Ω). The curved shapes of these objects were confirmed by AFM and SEM imaging. Non-planar Ω - nanostructures open up new possibilities for graphene electron energy band engineering. 相似文献
982.
983.
Mun Ho Kim Doo-Jin Byun Ji-Eun You Kil-Yeong Choi 《Journal of Industrial and Engineering Chemistry》2013,19(3):920-925
The white-colored inner surface of a polypropylene (PP) material containing water discolored and turned yellow. The discoloration occurred selectively on the surface at the point of contact with the air–water interface. Since the polymer surface was exposed to water in darkness at room temperature, no sign of deterioration or degradation of the polymer at the discolored surface was confirmed. This study conducts an in-depth analysis of the discoloration mechanism of the polymer surface. A variety of technical approaches, including microscopic, spectroscopic, and chromatographic analysis techniques, were used to investigate the nature of discoloration and the root cause. From the analysis results, the discoloration was ascribed principally to a phenol transformation compound having the structure of a quinone methide, which was identified as a degradation product of a primary antioxidant. Based on the observations and experimental results, a plausible discoloration mechanism was proposed. 相似文献
984.
Sara Alcorn Amanda J. Walker Nishant Gandhi Amol Narang Aaron T. Wild Russell K. Hales Joseph M. Herman Danny Y. Song Theodore L. DeWeese Emmanuel S. Antonarakis Phuoc T. Tran 《International journal of molecular sciences》2013,14(7):14800-14832
As our understanding of the molecular pathways driving tumorigenesis improves and more druggable targets are identified, we have witnessed a concomitant increase in the development and production of novel molecularly targeted agents. Radiotherapy is commonly used in the treatment of various malignancies with a prominent role in the care of prostate cancer patients, and efforts to improve the therapeutic ratio of radiation by technologic and pharmacologic means have led to important advances in cancer care. One promising approach is to combine molecularly targeted systemic agents with radiotherapy to improve tumor response rates and likelihood of durable control. This review first explores the limitations of preclinical studies as well as barriers to successful implementation of clinical trials with radiosensitizers. Special considerations related to and recommendations for the design of preclinical studies and clinical trials involving molecularly targeted agents combined with radiotherapy are provided. We then apply these concepts by reviewing a representative set of targeted therapies that show promise as radiosensitizers in the treatment of prostate cancer. 相似文献
985.
Objective: Although current evidence suggests that the positive effects of multisystemic therapy (MST) on serious crime reach as far as young adulthood, the longer term impact of MST on criminal and noncriminal outcomes in midlife has not been evaluated. In the present study, the authors examined a broad range of criminal and civil court outcomes for serious and violent juvenile offenders who participated on average 21.9 (range = 18.3–23.8) years earlier in a clinical trial of MST (C. M. Borduin et al., 1995). Method: Participants were 176 individuals who were originally randomized to MST or individual therapy (IT) during adolescence and averaged 3.9 arrests for felonies prior to treatment. Arrest, incarceration, and civil suit data were obtained in middle adulthood when participants were on average 37.3 years old. Results: Intent-to-treat analyses showed that felony recidivism rates were significantly lower for MST participants than for IT participants (34.8% vs. 54.8%, respectively) and that the frequency of misdemeanor offending was 5.0 times lower for MST participants. In addition, the odds of involvement in family-related civil suits during adulthood were twice as high for IT participants as for MST participants. Conclusions: The present study represents the longest follow-up to date of an MST clinical trial and demonstrates that the positive impact of an evidence-based youth treatment such as MST can last well into adulthood. Implications of the authors' findings for policymakers and service providers are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
986.
Salzer Simone; Pincus Aaron L.; Winkelbach Christel; Leichsenring Falk; Leibing Eric 《Canadian Metallurgical Quarterly》2011,48(3):304
Interpersonal problems are highly relevant to the treatment of generalized anxiety disorder (GAD) patients. Previous studies using the Inventory of Interpersonal Problems identified several interpersonal subtypes in GAD patients. In this study, we wanted to replicate earlier findings of interpersonal subtypes in GAD. We investigated whether these interpersonal subtypes are characterized by different types of interpersonal problems and different levels of interpersonal distress, and we further examined whether they differed with regard to improvement of interpersonal problems after short-term treatment. This study is based on results from a randomized controlled trial that investigated short-term treatments in GAD outpatients. For secondary analysis, interpersonal subtypes were identified by cluster analysis and Inventory of Interpersonal Problems profiles were calculated for both the total sample (N = 52) and the interpersonal subtypes using the Structural Summary Method for Circumplex Data. This study confirmed previous results demonstrating the existence of interpersonal subtypes in GAD. Four interpersonal subtypes were identified: Overly Nurturant, Intrusive, Socially Avoidant, and Nonassertive. Short-term treatment significantly improved interpersonal problems (d = 0.46) within the total GAD sample. Interestingly, the effect sizes of the four clusters differed considerably (d = 0.19–1.24) and the clusters displayed different changes in the two circumplex axes Dominance and Nurturance. Our study indicates that change of interpersonal problems needs to be specifically analyzed, even within homogenous diagnostic groups. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
987.
Morteza Esmaeili T. Aaron Gulliver Norman P. Secord 《Applicable Algebra in Engineering, Communication and Computing》1999,10(1):1-14
The atomic vectors of a finitely generated vector space C over a field F are characterized for C a subspace of the product vector space ? = ∏
i
=1
n
?
i
over F. For finite fields, the minimal trellis diagram for mixed-codes is determined, and this provides the L-section minimal trellis diagram for linear codes. As an example, an extremely simple yet comprehensive analysis of the trellis
structure of Reed-Muller codes is given. In particular, a trellis oriented generator matrix for the 2
l
-section minimal trellis diagram of a Reed-Muller code is presented.
Received: February 27, 1997; revised version: May 6, 1999 相似文献
988.
The performance of iPP/LDPE blends in an extrusion coating process was investigated in the terms of coating width and draw‐down ability. It is well known that iPP alone is not proper because of lower draw‐down ability with severe draw resonance in elongational flow. To obtain higher draw‐down ability, iPP was blended with LDPE. Additionally, iPPs having different molecular weight distribution (MWD) were used in this study to find out the effect of MWD of iPP on neck‐in and draw‐down ability. It was observed that iPP/LDPE blend with narrower MWD exhibits narrower coating width and higher draw‐down ability. Neck‐in and draw‐down ability were correlated with shear and elongational properties obtained by several rheological measurements. From this study, the major rheological parameters affecting extrusion performance in iPP/LDPE blends could be assessed. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
989.
The insecticidal activity of five alkylfurans against the generalist insect herbivore beet armyworm, Spodoptera exigua, was examined. Two naturally occurring compounds, the avocadofurans 2-(pentadecyl)furan (1) and 2-(heptadecyl)furan (2), previously isolated from specialized avocado idioblast oil cells, and three homologues, 2-(tetradecyl)furan (3), 2-(hexadecyl)furan (4), and 2-(octadecyl)furan (5), were synthesized. Bioassays of alkylfurans 1-5 using a 9-day diet-incorporation initiated with neonates showed that all alkylfurans tested significantly increased S. exigua larval mortality and reduced larval weights, with maximal biological activity detected among the naturally occurring alkylfurans 1 and 2. 相似文献
990.
A study of brain lipids in patients with the sphingomyelinase-deficient types of Niemann-Pick disease demonstrated that abnormal accumulation of sphingomyelin occurs only in the brain of neuronopathic type A patients but not in the non-neuronopathic type B. Additional lipid abnormalities were present in the type A brain. In contrast, the brain lipid profile was normal in type B patients. Since lysosphingolipids have been implicated in the biochemical pathogenesis of other genetic lysosomal sphingolipidoses, the occurrence of sphingosylphosphorylcholine (lysosphingomyelin) was specifically investigated in brain and extraneural tissues, using an HPLC method with fluorescent detection of orthophtalaldehyde derivatives. Levels close to or below the limit of detection (10 pmol/mg tissue protein) were observed in normal and pathological controls. A striking accumulation was observed in brain of two Niemann-Pick type A patients (830 and 430 pmol/mg protein in 27-and 16-month-old children with severe and milder neurological course, respectively), which was not present at the fetal stage of the disease. No significant increase was found in brain tissue from a 3.5 year-old type B patient. In liver and spleen, abnormally high sphingosylphosphorylcholine levels were observed in both types of the disease, with indication of a progressive increase during development. This study establishes the integrity of brain tissue in Niemann-Pick disease type B and suggests that the lysocompound sphingosylphosphorylcholine could play a role in the pathophysiology of brain dysfunction in the neuronopathic type A. 相似文献