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51.
52.
Michael D. Hogan Lisa J. Carnahan Robert J. Carpenter David W. Flater James E. Fowler Simon P. Frechette Martha M. Gray L. Arnold Johnson R. Michael McCabe Douglas Montgomery Shirley M. Radack Robert Rosenthal Craig M. Shakarji 《Journal of research of the National Institute of Standards and Technology》2001,106(1):341-370
Our high technology society continues to rely more and more upon sophisticated measurements, technical standards, and associated testing activities. This was true for the industrial society of the 20th century and remains true for the information society of the 21st century. Over the last half of the 20th century, information technology (IT) has been a powerful agent of change in almost every sector of the economy. The complexity and rapidly changing nature of IT have presented unique technical challenges to the National Institute of Standards and Technology (NIST) and to the scientific measurement community in developing a sound measurement and testing infrastructure for IT. This measurement and testing infrastructure for the important non-physical and non-chemical properties associated with complex IT systems is still in an early stage of development. This paper explains key terms and concepts of IT metrology, briefly reviews the history of the National Bureau of Standards/National Institute of Standards and Technology (NBS/NIST) in the field of IT, and reviews NIST’s current capabilities and work in measurement and testing for IT. It concludes with a look at what is likely to occur in the field of IT over the next ten years and what metrology roles NIST is likely to play. 相似文献
53.
Hui Zhi Shirley Lee Prof. Weng Kee Leong Dr. Siden Top Dr. Anne Vessières 《ChemMedChem》2014,9(7):1453-1457
A structure–activity relationship (SAR) study of the triosmium carbonyl cluster Os3(CO)10(NCCH3)2 was carried out with a series of clusters of the general formula Os3(CO)12?nLn, cationic osmium clusters and a hemi‐labile maltolato‐Os cluster. The SAR results showed that good solubility in DMSO and at least one vacant site are required for cytotoxicity. In vitro evaluation of these new compounds showed that some are selectively active against estrogen receptor (ER)‐independent MDA‐MB‐231 breast cancer cell lines relative to ER‐dependent MCF‐7 breast cancer cells, suggesting that the compounds have a different biological target specific to MDA‐MB‐231 cells. In particular, the maltolato cluster exhibits strong antiproliferative activity, with an IC50 value of 3 μM after only 24 h incubation. Additionally, biochemical assays conducted with the cationic cluster show that it induces apoptosis, although a biological target has not yet been identified. Further research to establish the molecular targets of these compounds and to develop improved organometallic clusters as potential breast cancer therapeutics is underway. 相似文献
54.
Karen Chou Chang-Yi Lin rew Huang Rochelle Inglis Shirley Lin 《Lakes & Reservoirs: Research and Management》2002,7(3):231-239
The long‐term effects of Great Lakes' contaminants on male reproductive performance resulting from lactational and dietary exposure were investigated. Female C57BL/6 J mice (F‐0) were mated with DBA/2 J male mice to produce B6D2‐F1 offspring. Dams (F‐0) were fed one of three treatment diets during lactation. The three treatment diets were: (i) diet C, containing lab chow and fish oil; (ii) diet I, containing 60% Iowa carp and 40% lab chow; and (iii) diet G, containing 60% Great Lakes' carp and 40% lab chow. Diet C served as a lab‐chow control treatment, while diet I served as a fish‐diet control treatment. Diet G contained 2500 µg of polychlorinated biphenyls (PCBs) and 300 µg of 1,1‐dichloro‐2,2‐bis‐[p‐chlorophenyl]ethylene (4,4′‐DDE) per kilogram of feed. The offspring (F‐1) were continued on their respective maternal treatment diets from weaning until termination. Greater neonatal mortality and lesser body weights were observed in the F‐1 male mice on diet G. Lesser fecundity was observed in one‐year‐old F‐1 male mice on diet G following pairing with non‐treated female mice. The sperm concentration of F‐1 male mice on diet G was less than 30% of that of mice on diets C and I. The in vitro fertilizing ability of the sperm decreased to 10% of that of mice on the two control diets. Sperm motility, velocity, linearity and amplitude of lateral head (ALH) displacement were also decreased in 15‐month‐old F‐1 male mice on diet G. 相似文献
55.
Milan Rusnak Shirley B House Hiroshi Arima Harold Gainer 《Microscopy research and technique》2002,56(2):101-112
Organotypic cultures of the rat hypothalamus are very useful models for the long-term study of parvocellular vasopressin (VP) neurons in the paraventricular (PVN) and suprachiasmatic (SCN) nuclei. However, they do not preserve significant numbers of VP magnocellular neurons (VP-MCNs) in either the PVN or the supraoptic nucleus (SON). Vutskits et al. [(1998) Neuroscience 87:571-582] reported that ciliary neurotrophic factor (CNTF) was a selective survival factor for rat VP-MCNs in organotypic cultures of the rat hypothalamic paraventricular nucleus (PVN). We examined the effects of CNTF on the survival of these neurons in rat and mouse SONs. CNTF (10 ng/ml) in the culture media increased the survival of VP-MCNs by 6-fold and OT-MCNs by 3-fold. In the mouse, both OT- and VP-MCNs survive very well in organotypic cultures under standard culture conditions and the addition of CNTF had no further effect. Consistent with these results, in situ hybridization showed substantially higher levels of VP- and OT-mRNA in rat PVNs and SONs in the presence of CNTF, but produced no changes in these nuclei in the mouse. The optimum period for the survival effect of CNTF on MCNs in the rat hypothalamic cultures was in the first 7-10 days of culture and this effect is maintained for at least 5 additional days if CNTF is then removed from the medium. Therefore, using CNTF in the culture media can provide an opportunity for long-term studies of rat VP- and OT-MCNs in SONs in organotypic cultures. 相似文献
56.
With a sample of 116, the authors asked how characteristics of the family, rated by adolescents, predicted health risk behavior at young adulthood 6 years later and whether adolescent and young adult personal and emotional functioning mediated these relationships. The authors also explored the consistency of relationships among these variables across 4 types of families: balanced, traditional, disconnected, and emotionally strained. The family variables significantly predicted young adult health risk behavior over time and functioning at adolescence and young adulthood did not serve as a mediator. The family model operated well in 3 of the 4 family contexts; it failed to operate among offspring from disconnected families. Characteristics of the family affect the display of health risk behavior when offspring come from families that have well-defined and coherent family structures. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
57.
Bagley Shirley P.; Angel Ronald; Dilworth-Anderson Peggye; Liu William; Schinke Steven 《Canadian Metallurgical Quarterly》1995,14(7):632
Race. ethnicity. and cultural attitudes and practices are among the variables that influence health behaviors. including adaptive health behaviors. The following discussions highlight the important role of social conditions in shaping health behaviors and the central role of family in promoting health across the Asian, Hispanic. Native American, and African American ethnic groups. Factors that may lead to health-damaging behaviors are also discussed. The need for additional research that identifies correlations among physiological, social. and behavioral factors and health behaviors, as well as underlying mechanisms, is called for. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
58.
Songfeng Guo Garrett G Grindle Erica L Authier Rory A Cooper Shirley G Fitzgerald Annmarie Kelleher Rosemarie Cooper 《IEEE transactions on neural systems and rehabilitation engineering》2006,14(1):83-90
Increased physical activity is important for reducing the risk of cardiovascular disease. However, among people with disabilities, inactivity is prevalent. In order to encourage exercise among members of this group, an exercise system combining arm ergometry with video gaming, called the GAME(Cycle) was previously developed. User input was received through an arm crank ergometer on a swivel, with the angular velocity of the ergometer resistance wheel controlling one axis and rotation of ergometer about the swivel controlling the other. The purpose of this study was to detail the algorithms used in this device and present novel features included in a second generation of the GAME(Cycle). The features include a wheel on base, a steering return mechanism, and wireless fire buttons. A focus group of clinicians (n = 8), wheelchair users (n = 8), and clinician wheelchair users (n = 2) was conducted to evaluate the features of the GAME(Cycle). The focus group suggested improvements to the steering mechanism and to reduce vibration in the system. However, the focus group enjoyed the GAME(Cycle) and felt that it would encourage exercise among persons with disabilities. 相似文献
59.
O'Connor Thomas G.; McGuire Shirley; Reiss David; Hetherington E. Mavis; Plomin Robert 《Canadian Metallurgical Quarterly》1998,107(1):27
Recent reviews of research on child and adolescent psychopathology have highlighted the consistently high rates of co-occurring dimensions of psychopathology, particularly between internalizing and externalizing disorders, and have suggested that further research examining the causes of co-occurring syndromes is needed. The authors examined this question in a national sample of 720 same-sex adolescent siblings between 10 and 18 years of age consisting of monozygotic and dizygotic twins, full siblings, half siblings, and unrelated siblings. Composite measures of adolescent and parent reports and observational measures of depressive symptoms and antisocial behavior were subjected to behavioral genetic models that examine the genetic and environmental influences on individual differences in each dimension as well as in the co-occurrence between dimensions. Results indicated that approximately half of the variability in depressive symptoms and antisocial behavior is attributed to genetic factors; shared and nonshared environmental influences were also significant. The co-occurrence of depressive and antisocial symptoms was explained by genetic and shared and nonshared environmental influences. Specifically, approximately 45% of the observed covariation between depressive and antisocial symptoms could be explained by a common genetic liability. Results are interpreted in light of contribution of genetic studies to debates on child and adolescent psychopathology. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
60.
Knox Sarah; Hess Shirley A.; Petersen David A.; Hill Clara E. 《Canadian Metallurgical Quarterly》1997,44(3):274
Thirteen adult psychotherapy clients currently in long-term therapy were interviewed twice, with semistructured protocols, about their experiences with helpful instances of therapist self-disclosure. Data were analyzed with a qualitative methodology. Results indicated that helpful therapist self-disclosures (a) occurred when these clients were discussing important personal issues, (b) were perceived as being intended by therapists to normalize or reassure the clients, and (c) consisted of a disclosure of personal nonimmediate information about the therapists. The therapist self-disclosures resulted in positive consequences for these clients that included insight or a new perspective from which to make changes, an improved or more equalized therapeutic relationship, normalization, and reassurance. Implications for psychotherapy are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献