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141.
Lightman B 《Isis; an international review devoted to the history of science and its cultural influences》2000,91(4):651-680
This essay examines the use of visual images during the latter half of the nineteenth century in the work of three important popularizers of science. J. G. Wood, Richard Proctor, and Agnes Clerke skillfully used illustrations and photographs to establish their credibility as trustworthy guides to scientific, moral, and religious truths. All three worked within the natural theology tradition, despite the powerful critique of William Paley's argument from design set forth in Charles Darwin's Origin of Species (1859). Wood, Proctor, and Clerke recognized that in order to reach a popular audience with their message of divine wonder in nature, they would have to take advantage of the developing mass visual culture embodied in the new pictorial magazines, spectacles, and entertaining toys based on scientific gadgets emblematic of the reorganization of vision. But in drawing on different facets of the emerging visual culture and in looking to the images produced by the new visual technologies to find the hand of God in nature, these popularizers subtly transformed the natural theology tradition. 相似文献
142.
143.
T. Malati G. Rajani Kumari P. V. L. N. Murthy Ch. Ram Reddy B. Surya Prakash 《Indian journal of clinical biochemistry : IJCB》2006,21(1):34-40
Prostate Specific Antigen (PSA) has emerged as the most applicable and important tumor marker for carcinoma prostate. In the
present study PSA was determined in serum of healthy subjects, patients of benign prostate hypertrophy (BPH) and Carcinoma
Prostate (Ca−P) to evaluate its diagnostic efficiency in day to day management of prostate cancer patients and in differentiating
patients of early prostate cancer from those with BPH. Receiver operating characteristic curve (ROC) revealed 2 ng/ml and
10 ng/ml cut off serum PSA level for BPH and untreated carcinoma prostate patients (Ca−P). An extremely significant increase
(P<0.0001) was observed in mean PSA concentration in BPH patients and adenocarcinoma prostate patients when compared to healthy
males. Clinical relevance of PSA was highlighted by a case study of cancer patient prior to any therapy till death. 相似文献
144.
C.S. Badue R. Baeza-Yates B. Ribeiro-Neto A. Ziviani N. Ziviani 《Information processing & management》2007
The performance of parallel query processing in a cluster of index servers is crucial for modern web search systems. In such a scenario, the response time basically depends on the execution time of the slowest server to generate a partial ranked answer. Previous approaches investigate performance issues in this context using simulation, analytical modeling, experimentation, or a combination of them. Nevertheless, these approaches simply assume balanced execution times among homogeneous servers (by uniformly distributing the document collection among them, for instance)—a scenario that we did not observe in our experimentation. On the contrary, we found that even with a balanced distribution of the document collection among index servers, correlations between the frequency of a term in the query log and the size of its corresponding inverted list lead to imbalances in query execution times at these same servers, because these correlations affect disk caching behavior. Further, the relative sizes of the main memory at each server (with regard to disk space usage) and the number of servers participating in the parallel query processing also affect imbalance of local query execution times. These are relevant findings that have not been reported before and that, we understand, are of interest to the research community. 相似文献
145.
Two property regimes for software development may be distinguished. Within corporations, on the one hand, a Private Regime obtains which excludes all outsiders from access to a firm's software assets. It is shown how the protective instruments of secrecy and both copyright and patent have been strengthened considerably during the last two decades. On the other, a Public Regime among hackers may be distinguished, initiated by individuals, organizations or firms, in which source code is freely exchanged. It is argued that copyright is put to novel use here: claiming their rights, authors write ‘open source licenses’ that allow public usage of the code, while at the same time regulating the inclusion of users. A ‘regulated commons’ is created. The analysis focuses successively on the most important open source licenses to emerge, the problem of possible incompatibility between them (especially as far as the dominant General Public License is concerned), and the fragmentation into several user communities that may result. 相似文献
146.
Thomas B. Åstebro 《Research Policy》2005,34(9):1404-1418
Research on technological opportunity has typically focused on the impact of broad industry characteristics on R&D intensity of firms. This study complements such approaches by examining the impact of a multidimensional vector that measures technological opportunity on independent inventors’ decisions to patent and commercialize inventions. Using data from 559 inventions and controlling for demand, appropriability, and competitive conditions, we found two of four tested dimensions of technological opportunity - technical performance and technical uncertainty - to be significant and important determinants of the likelihood of commercialization. Technical feasibility appears important in affecting patenting but unimportant in affecting commercialization. Technical significance carries a negative, although insignificant, sign conditioning commercialization. 相似文献
147.
Vaughan Van Hecke A Mundy PC Acra CF Block JJ Delgado CE Parlade MV Meyer JA Neal AR Pomares YB 《Child development》2007,78(1):53-69
Infant joint attention has been observed to be related to social-emotional outcomes in at-risk children. To address whether this relation is also evident in typically developing children, 52 children were tested at 12, 15, 24, and 30 months to examine associations between infant joint attention and social outcomes. Twelve-month initiating and responding to joint attention were related to 30-month social competence and externalizing behavior, even when accounting for 15-month temperament ratings, 24-month cognition and language, and demographic variables. These results suggest that, in addition to associations with language and cognition, infant joint attention reflects robust aspects of development that are related to individual differences in the emergence of social and behavioral competence in childhood. 相似文献
148.
The understanding and use of historical concepts specified in national history standards pose many challenges to students. These challenges include both the acquisition of content knowledge and the use of that knowledge in ways that require higher order thinking. All students, including adolescents with learning disabilities (LD), are expected to understand and use concepts of history to pass high-stakes assessments and to participate meaningfully in a democratic society. This article describes Content Enhancement Routines (CERs) to illustrate instructional planning, teaching, and assessing for higher order thinking with examples from an American history unit. Research on the individual components of Content Enhancement Routines will be illustrated with data from 1 of the routines. The potential use of integrated sets of materials and procedures across grade levels and content areas will be discussed. 相似文献
149.
Although religiosity promotes resilient outcomes in African American (AA) adolescents, there is a lack of research that examines the protective role of religious development in the context of stressful life events (SLEs). In 1,595 AA adolescents, a cohort-sequential design was used from ages 12 to 18 to examine subtypes of religiosity, as well as distinct developmental patterns within subtypes. The protective role of religious development was also examined in the context of SLEs. The study findings indicated two subtypes of religiosity—extrinsic and intrinsic religiosity—as well as low and high developmental patterns in the identified subtypes. Furthermore, the protective influence of extrinsic and intrinsic religiosity gradually diminished from age 12 to 18 in the context of SLEs. 相似文献
150.
Although much attention has been given to rater effects in rater‐mediated assessment contexts, little research has examined the overall stability of leniency and severity effects over time. This study examined longitudinal scoring data collected during three consecutive administrations of a large‐scale, multi‐state summative assessment program. Multilevel models were used to assess the overall extent of rater leniency/severity during scoring and examine the extent to which leniency/severity effects were stable across the three administrations. Model results were then applied to scaled scores to estimate the impact of the stability of leniency/severity effects on students’ scores. Results showed relative scoring stability across administrations in mathematics. In English language arts, short constructed response items showed evidence of slightly increasing severity across administrations, while essays showed mixed results: evidence of both slightly increasing severity and moderately increasing leniency over time, depending on trait. However, when model results were applied to scaled scores, results revealed rater effects had minimal impact on students’ scores. 相似文献