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71.
Morgan James L.; Bonamo Katherine M.; Travis Lisa L. 《Canadian Metallurgical Quarterly》1995,31(2):180
Previous work has shown that recasts may be contingent responses to children's early ungrammaticality. On this basis, it has been claimed that recasts provide negative evidence, thereby offsetting the need for linguistic constraints in theories of acquisition. This study explores whether children exploit negative evidence putatively provided by recasts by examining whether parental recasts are associated with children's recovery from particular overgeneralization errors. Data from longitudinal investigations of 2 common syntactic errors reveal that recasts are related to children's subsequent grammaticality. However, contrary to what would be expected if recasts serve as corrections, the data show that recasts are negative leading indicators of grammaticality. Finally, correction and negative evidence are examined and are shown to be nonequivalent. Therefore, corrections in whatever form they might exist can offset only a limited subset of proposed innate constraints on language acquisition. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
72.
DB Flieder MN Koss A Nicholson IA Sesterhenn RE Petras WD Travis 《Canadian Metallurgical Quarterly》1998,22(11):1328-1342
Solitary endobronchial papillomas in adults are rare neoplasms. Only sporadic cases have been documented. The histologic classification of these tumors remains problematic, and little is known about their clinical behavior. The clinical and pathologic features of 13 endobronchial papillomas and a single endobronchiolar papilloma were reviewed. In situ hybridization for human papillomavirus (HPV) types 6/11, 16/18, and 31/33/51 was performed on seven cases. Twenty-seven additional well-documented cases were identified in a literature review. Human papillomavirus studies were performed in four of the previously reported cases. The 41 neoplasms combined from the Armed Forces Institute of Pathology and literature review were divided into three groups according to their histologic features. Thirty-one of 41 (76%) patients were men. The ages of the patients ranged from 26 to 74 years (median, 57 years). Three morphologically distinct histologic types were recognized; 27 squamous cell papillomas, 7 glandular papillomas, and 7 mixed squamous and glandular papillomas. Squamous papillomas: 23 of 27 (85%) patients were men, and the median age was 54 years. Six of eleven (55%) of these patients smoked. Twenty-six lesions were exophytic and a single lesion had an inverted pattern. Seven of 24 (29%) lesions featured cytologic atypia and 5 of 24 (14%) had viral cytopathic effect. Five of seven (71%) cases examined for HPV DNA were positive. Three of 18 (17%) recurred. Glandular papillomas: Four of seven (57%) patients were women. The mean age was 67 years. One of five (20%) patients smoked. Five lesions were central, and two were peripheral. Four lesions had columnar epithelium, and three had ciliated epithelium. One of six (17%) lesions recurred. Mixed papillomas: five of seven (71%) patients were men. The median age was 64 years. Three of five (60%) patients smoked. Three of seven (43%) lesions featured cytologic atypia. Four of five lesions were examined for HPV DNA and all were negative. No lesions recurred. This study demonstrates that solitary endobronchial papillomas can be separated into three distinct morphologic categories. Squamous cell and mixed papillomas are predominantly lesions of male smokers in their 6th decade. Although cytologic atypia is observed in many cases, the rarity of these tumors and difficulty in separating papillomas from endobronchial papillary squamous carcinomas make generalizations regarding the risk of progression to carcinoma tenuous at best. Human papillomavirus appears to play a pathogenetic role in some squamous cell papillomas, but not in mixed papillomas, yet its presence in the squamous lesions does not correlate with recurrence or malignancy. The first report of an inverted squamous cell papilloma indicates clinical features similar to the more common exophytic squamous cell papillomas. Glandular papillomas, the rarest of all endobronchial papillomas, are found in an older age group than squamous and mixed papillomas, and most-patients are nonsmokers. Based on these findings, all endobronchial papillomas should be completely excised. 相似文献
73.
We examined the effects of intracisternal (i.c.) injections (10-250 nmol) of the L- and D-isomers of S-nitrosocysteine (L- and D-S-nitrosocysteine) on the mean arterial blood pressure and heart rate of conscious rats, and the decomposition of L- and D-S-nitrosocysteine to nitric oxide (NO) upon addition to brain homogenates. The i.c. injection of L-S-nitrosocysteine produced initial falls in mean arterial blood pressure and heart rate which were followed by increases in these parameters. The i.c. injection of D-S-nitrosocysteine did not produce initial falls in mean arterial blood pressure or heart rate but produced the subsequent increases in these parameters. L- and D-S-nitrosocysteine decomposed equally to NO. These results suggest that the initial effects of L-S-nitrosocysteine may be due to the activation of stereoselective recognition sites on brain neurons. 相似文献
74.
Travis Williams 《电子设计技术》2004,11(10)
鉴于USB(通用串行总线)ASIC控制器的线宽不断变小,迫使物理层从控制器中分离出来,这使得许多系统设计人员认识到物理层独立的重要性.由于业界所需的分立物理层器件能与在较低VCC下工作的USB控制器接口,系统设计人员必须在符合USB2.0标准的系统中正确地引进物理层. 相似文献
75.
Wall Tamara L.; Shea Shoshana H.; Luczak Susan E.; Cook Travis A. R.; Carr Lucinda G. 《Canadian Metallurgical Quarterly》2005,114(3):456
Associations of alcohol dehydrogenase (ADH) gene polymorphisms (ADH1B*2 and ADH1C*1) with a lifetime alcohol use disorder (AUD) were examined in White college students. Alcohol-related endophenotypes likely to be influenced by elevations in acetaldehyde were also assessed. Individuals with an ADH1B*2 allele had lower rates of AUDs, consumed a lower maximum number of drinks in a 24-hr period, reported a greater level of response to alcohol, were more likely to have experienced alcohol-induced headaches following 1 or 2 drinks, and reported more severe hangovers than those lacking this allele. These findings are consistent with the hypothesis that enhanced sensitivity to alcohol and lower levels of alcohol use reflect the mechanism by which ADH1B*2 protects against developing an AUD. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
76.
James T. Gibbs Travis K. J. Williamson Steven J. Naber Thomas L. Macchiarella 《Canadian Metallurgical Quarterly》2002,128(9):891-901
A gasoline release site at the Dept. of Defense Housing Facility (DODHF) in Novato, Calif., resulted in dissolved methyl tertiary-butyl ether (MTBE) in a shallow, thin, heterogeneous aquifer. Multiple methods were used to evaluate the stability of the MTBE plume, including concentration versus time plots, isoconcentration contour maps, total dissolved MTBE mass and center of mass (COM) estimates, total plume extent changes, and parametric and nonparametric statistical techniques. The COM evaluation revealed a small upgradient shift in COM relative to both total plume extent and total MTBE mass reduction over the period examined. The total mass removal received substantial contributions from both the southern and northern portions of the plume, and the only removal mechanisms active in the northern plume were natural attenuation mechanisms. The results indicate that there exists at DODHF Novato a dissolved MTBE plume at the approximate balancing point between groundwater advection, which is carrying MTBE downgradient, and natural attenuation processes including aerobic biodegradation, which are reducing MTBE concentrations at about the same rate. 相似文献
77.
The reproducibility of short tandem repeat (STR) amplification of aDNA extracts is limited by means of formation of artifacts during PCR. One of these artifacts, the so called allelic-dropout (failure of the amplification of alleles), may result in false-homozygote typing of a sample, if genotyping is based on the analysis of a single amplification product. 30 tooth- and bone samples collected from 17 individuals of three burial sites were investigated in a blind test. Using the polymerase chain reaction (PCR) the two independent segregating STR-loci HUMVWA and HUMTH01 were amplified. Corresponding to a mathematical estimation, multiple amplifications of each sample and genelocus were carried out. The results of this genotyping were compared intraindividually. 相似文献
78.
Abbie E Smith Ashley A Walter Jennifer L Graef Kristina L Kendall Jordan R Moon Christopher M Lockwood David H Fukuda Travis W Beck Joel T Cramer Jeffrey R Stout 《Journal of the International Society of Sports Nutrition》2009,6(1):5
Background
Intermittent bouts of high-intensity exercise result in diminished stores of energy substrates, followed by an accumulation of metabolites, promoting chronic physiological adaptations. In addition, β-alanine has been accepted has an effective physiological hydrogen ion (H+) buffer. Concurrent high-intensity interval training (HIIT) and β-alanine supplementation may result in greater adaptations than HIIT alone. The purpose of the current study was to evaluate the effects of combining β-alanine supplementation with high-intensity interval training (HIIT) on endurance performance and aerobic metabolism in recreationally active college-aged men. 相似文献79.
Parrillo L.C. Pfiester J.R. Lin J.-H. Travis E.O. Sivan R.D. Gunderson C.D. 《Electron Devices, IEEE Transactions on》1991,38(1):39-46
An advanced 0.5-μm CMOS disposable lightly doped drain (LDD) spacer technology has been developed. This 0.5-μm CMOS technology features surface-channel LDD NMOS and PMOS devices, n+/p+ poly gates, 125-A-thick gate oxide, and Ti-salicided source/drain/gate regions. Using only two masking steps, the NMOS and PMOS LDD spacers are defined separately to provide deep arsenic n+ regions for lower salicided junction leakage, while simultaneously providing shallow phosphorus n- and boron p- regions for improved device short-channel effects. Additionally, the process allows independent adjustment of the LDD and salicide spacers to optimize the LDD design while avoiding salicide bridging of source/drain to gate regions. The results indicate extrapolated DC hot-carrier lifetimes in excess of 10 years for a 0.3-μm electrical channel-length NMOS device operated at a power-supply voltage of 3.3 V 相似文献
80.
平板投影光楔的图象质量 总被引:1,自引:0,他引:1
我们报道了一种厚度为20mm的14英寸平板投影显示屏,其亮度可达5000尼特、分辨率为600×800。这种显示器由现成的有机玻璃制成,使用只带梯形预畸变的无需调节的视频投影仪。在厚度为20mm对角线为50英寸屏幕上光学模拟预示XGA分辨率,亮度为500尼特、对比度与传统投影仪相当。 相似文献