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201.
T. Chalkley Palmer 《Journal of The Franklin Institute》1889,127(4):316-319
202.
Tångeberg P 《Endeavour》2000,24(4):147-151
The seventeenth-century Swedish Royal warship Vasa was painted and decorated with almost 500 figure sculptures and many carved ornaments. It is probably the most extensive sculptural work in wood to have been preserved from this period in European history. The ship's decorations are of particular importance given the scarcity of knowledge of how sculptures in general, and large ships in particular, were painted in Northern Europe during this period. About 20 different pigments have been characterized and it has been possible to reconstruct the appearance of many of the sculptures and to extend this knowledge to the ship's original appearance. 相似文献
203.
KDD, data mining, and the challenge for normative privacy 总被引:2,自引:1,他引:2
Herman T. Tavani 《Ethics and Information Technology》1999,1(4):265-273
The present study examines certain challenges that KDD (Knowledge Discovery in Databases) in general and data mining in particular pose for normative privacy and public policy. In an earlier work (see Tavani, 1999), I argued that certain applications of data-mining technology involving the manipulation of personal data raise special privacy concerns. Whereas the main purpose of the earlier essay was to show what those specific privacy concerns are and to describe how exactly those concerns have been introduced by the use of certain KDD and data-mining techniques, the present study questions whether the use of those techniques necessarily violates the privacy of individuals. This question is considered vis-à-vis a recent theory of privacy advanced by James Moor (1997). The implications of that privacy theory for a data-mining policy are also considered. 相似文献
204.
J. I. Anetor F I Ajose T. S Akingbola 《Indian journal of clinical biochemistry : IJCB》2005,20(1):193-197
A 64-year-old security guard and longstanding known hypertensive presented with hypertensive heart disease (HHD), weight loss,
an enlarged prostate, and a spontaneously fractured rib. Malignancy of the prostate with possible metastases to the ribs was
strongly suspected. Biochemical profiling revealed a paraprotein. Other biochemical and hematological correlates that were
on hand before serum protein electrophoresis were rather atypical. Paraprotein studies by immunofixation revealed IgA myelomatosis.
Unlike previous reports from Caucasians there was normocalcaemia, normal protein level, microcytic hypochromia, low MCHC,
cholesterol level at the lower limit of the reference range and normal urea level (in the face of markedly raised creatinine
level). Nutritional modulation of the classical laboratory features of this disease may account for the fairly atypical laboratory
picture.
The need to appreciate the influence of nutritional status on the laboratory (especially biochemical) features of a disease
and thus interpretation of diagnostic tests appears of exceptional current importance, given the widening gap in socioeconomic
status and the level of poverty between the resource poor and developed countries from which the classical, clinical and laboratory
features of most diseases were first described.
This case report reminds of the need not only to recognize theoretically the impact of nutritional status on the laboratory
characteristics of a disease but of the practical application of the nutritional perspective in the interpretation of diagnostic
investigations, especially in nutritionally disadvantaged communities. 相似文献
205.
Intersample optimization in a sampled-data control system using the redundancy of a dual-rate system
The present study discusses the design method for controlling a single-input/single-output linear time-invariant dual-rate system, where the sampling interval of the plant output is longer than the holding interval of the control input. In such a dual-rate system, the intersample output might oscillate even when the sampled output converges to the reference input in the steady state. In a conventional ripple-free method, an existing control law is extended by introducing an exogenous variable, which is independent of the discrete-time sampled response, and the exogenous variable is designed for eliminating the steady-state intersample ripples without changing the existing sampled response. In another method, since a control law is designed such that the intersample performance is optimized, the intersample ripples are eliminated in the transient as well as steady states. However, the preservation of an existing sampled response is not taken into account. The present study proposes a new design method for eliminating the intersample ripples subject to the existing sampled response. In the proposed method, the continuous-time index is optimized subject to the existing discrete-time response. As a result, the intersample ripples are eliminated in the transient as well as steady states, and the existing discrete-time sampled response is maintained. The proposed method is compared to the conventional dual-rate design methods in numerical examples, and the effectiveness of the method is demonstrated. 相似文献
206.
207.
Size-dependent trajectories of DNA macromolecules due to insulative dielectrophoresis in submicrometer-deep fluidic channels 总被引:1,自引:0,他引:1
Gea O. F. Parikesit Anton P. Markesteijn Oana M. Piciu Andre Bossche Jerry Westerweel Ian T. Young Yuval Garini 《Biomicrofluidics》2008,2(2)
In this paper, we demonstrate for the first time that insulative dielectrophoresis can induce size-dependent trajectories of DNA macromolecules. We experimentally use λ (48.5 kbp) and T4GT7 (165.6 kbp) DNA molecules flowing continuously around a sharp corner inside fluidic channels with a depth of 0.4 μm. Numerical simulation of the electrokinetic force distribution inside the channels is in qualitative agreement with our experimentally observed trajectories. We discuss a possible physical mechanism for the DNA polarization and dielectrophoresis inside confining channels, based on the observed dielectrophoresis responses due to different DNA sizes and various electric fields applied between the inlet and the outlet. The proposed physical mechanism indicates that further extensive investigations, both theoretically and experimentally, would be very useful to better elucidate the forces involved at DNA dielectrophoresis. When applied for size-based sorting of DNA molecules, our sorting method offers two major advantages compared to earlier attempts with insulative dielectrophoresis: Its continuous operation allows for high-throughput analysis, and it only requires electric field strengths as low as ∼10 V∕cm. 相似文献
208.
This paper constitutes an attempt to explore trends, issues and challenges that emerge when three different cohorts of pre-service teachers debate contemporary issues in science education at the University of Botswana. Apart from the author's experience of teaching the course, the impetus for this study also comes from a growing interest in the contemporary literature in the need for teachers who, in the context of globalization and knowledge economy, are ‘self-reforming’ through continually addressing the key issues of their profession. Unfortunately, the current situation is such that this burden of interrogation falls heaviest on teachers, despite their lack of skills in undertaking the task. 相似文献
209.
This study seeks to examine key extrinsic and intrinsic factors that encourage or discourage persistence in attaining an engineering degree and pursuing an engineering-related career among both male and female undergraduates. Quantitative and qualitative findings from nine participating undergraduate degree programmes reveal that career expectations formulated through educational experiences as undergraduates play a key role in motivating students. Among females, faculty interaction in the classroom, such as feedback received and the degree to which the faculty treat them with respect, is an important encouraging factor. For both males and females, discouraging elements of the undergraduate experience include the amount of time for coursework, competition in engineering classes and grades. The findings have several practical implications that faculty and administrators can employ in shaping the undergraduate experience to encourage short- and long-term interest in engineering among both male and female students. 相似文献
210.
Megan E. Pratt Shannon T. Lipscomb Megan M. McClelland 《Early education and development》2016,27(4):421-439
Research Findings: The current study examined how children’s parent-reported compliance at age 3 (36 months) moderated the effects of 2 dimensions of directly observed early care and education (ECE) process quality (positivity/responsivity and cognitive stimulation) during the prekindergarten year (54 months) on teacher reports of children’s classroom cooperation in the fall of kindergarten. Compliance at 36 months and cooperation in kindergarten are operationalized as overt, behavioral aspects of self-regulation as appraised by parents and teachers. The sample consisted of 996 children from the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development who attended formal or informal ECE settings during the prekindergarten year. Results indicated that children with low compliance at age 3 tend to demonstrate stronger cooperation skills by kindergarten when they experience more positivity/responsivity from their ECE caregivers. Main effects of positivity/responsivity and cognitive stimulation on classroom cooperation were not detected for the overall sample. Practice or Policy: The discussion addresses the importance of preparing and empowering ECE providers to help young children who enter the preschool period struggling with behavioral aspects of self-regulation, such as compliance, to improve these skills through positive and responsive caregiving. 相似文献