882 resultados para Harpring, Jack
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The purpose of this paper is to examine the extent to which the existing US Coastal Zone Management (CZM) program represents Integrated Coastal Management (ICM). The actions taken at Rio de Janeiro in June 1992 as part of the United Nations Conference on Environment and Development (UNCED) could eventually impact the policies of the US in such a way as to encourage better integration of US coastal and ocean management efforts.
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The consequence of activation status or gain/loss of an X-chromosome in terms of the expression of tumor suppressor genes or oncogenes in breast cancer has not been clearly addressed. In this study, we investigated the activation status of the X-chromosomes in a panel of human breast cancer cell lines, human breast carcinoma, and adjacent mammary tissues and a panel of murine mammary epithelial sublines ranging from low to high invasive potentials. Results show that most human breast cancer cell lines were homozygous, but both benign cell lines were heterozygous for highly polymorphic X-loci (IDS and G6PD). On the other hand, 60% of human breast carcinoma cases were heterozygous for either IDS or G6PD markers. Investigation of the activation status of heterozygous cell lines revealed the presence of only one active X-chromosome, whereas most heterozygous human breast carcinoma cases had two active X-chromosomes. Furthermore, we determined whether or not an additional active X-chromosome affects expression levels of tumor suppressor genes and oncogenes. Reverse transcription-PCR data show high expression of putative tumor suppressor genes Rsk4 and RbAp46 in 47% and 79% of breast carcinoma cases, respectively, whereas Cldn2 was down-regulated in 52% of breast cancer cases compared with normal adjacent tissues. Consistent with mRNA expression, immunostaining for these proteins also showed a similar pattern. In conclusion, our data suggest that high expression of RbAp46 is likely to have a role in the development or progression of human breast cancer. The activation status of the X-chromosome may influence the expression levels of X-linked oncogenes or tumor suppressor genes.
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There is a need for methodology to warm open-field plots in order to study the likely effects of global warming on ecosystems in the future. Herein, we describe the development of arrays of more powerful and efficient infrared heaters with ceramic heating elements. By tilting the heaters at 45 degrees from horizontal and combining six of them in a hexagonal array, good uniformity of warming was achieved across 3-m-diameter plots. Moreover, there do not appear to be obstacles (other than financial) to scaling to larger plots. The efficiency [eta(h) (%); thermal radiation out per electrical energy in] of these heaters was higher than that of the heaters used in most previous infrared heater experiments and can be described by: eta(h) = 10 + 25exp(-0.17 u), where u is wind speed at 2 m height (m s(-1)). Graphs are presented to estimate operating costs from degrees of warming, two types of plant canopy, and site windiness. Four such arrays were deployed over plots of grass at Haibei, Qinghai, China and another at Cheyenne, Wyoming, USA, along with corresponding reference plots with dummy heaters. Proportional integral derivative systems with infrared thermometers to sense canopy temperatures of the heated and reference plots were used to control the heater outputs. Over month-long periods at both sites, about 75% of canopy temperature observations were within 0.5 degrees C of the set-point temperature differences between heated and reference plots. Electrical power consumption per 3-m-diameter plot averaged 58 and 80 kW h day(-1) for Haibei and Cheyenne, respectively. However, the desired temperature differences were set lower at Haibei (1.2 degrees C daytime, 1.7 degrees C night) than Cheyenne (1.5 degrees C daytime, 3.0 degrees C night), and Cheyenne is a windier site. Thus, we conclude that these hexagonal arrays of ceramic infrared heaters can be a successful temperature free-air-controlled enhancement (T-FACE) system for warming ecosystem field plots.
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Combining numerical techniques with ideas from symbolic computation and with methods incorporating knowledge of science and mathematics leads to a new category of intelligent computational tools for scientists and engineers. These tools autonomously prepare simulation experiments from high-level specifications of physical models. For computationally intensive experiments, they automatically design special-purpose numerical engines optimized to perform the necessary computations. They actively monitor numerical and physical experiments. They interpret experimental data and formulate numerical results in qualitative terms. They enable their human users to control computational experiments in terms of high-level behavioral descriptions.
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Cyclic changes in the shape of a quasi-rigid body on a curved manifold can lead to net translation and/or rotation of the body in the manifold. Presuming space-time is a curved manifold as portrayed by general relativity, translation in space can be accomplished simply by cyclic changes in the shape of a body, without any thrust or external forces.
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Classical mechanics is deceptively simple. It is surprisingly easy to get the right answer with fallacious reasoning or without real understanding. To address this problem we use computational techniques to communicate a deeper understanding of Classical Mechanics. Computational algorithms are used to express the methods used in the analysis of dynamical phenomena. Expressing the methods in a computer language forces them to be unambiguous and computationally effective. The task of formulating a method as a computer-executable program and debugging that program is a powerful exercise in the learning process. Also, once formalized procedurally, a mathematical idea becomes a tool that can be used directly to compute results.
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I describe an approach to forming hypotheses about hidden mechanism configurations within devices given external observations and a vocabulary of primitive mechanisms. An implemented causal modelling system called JACK constructs explanations for why a second piece of toast comes out lighter, why the slide in a tire gauge does not slip back inside when the gauge is removed from the tire, and how in a refrigerator a single substance can serve as a heat sink for the interior and a heat source for the exterior. I report the number of hypotheses admitted for each device example, and provide empirical results which isolate the pruning power due to different constraint sources.
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How does a person answer questions about children's stories? For example, consider 'Janet wanted Jack's paints. She looked at the picture he was painting and said 'Those paints make your picture look funny.' The question to ask is 'Why did Janet say that?'. We propose a model which answers such questions by relating the story to background real world knowledge. The model tries to generate and answer important questions about the story as it goes along. Within this model we examine two questions about the story as it goes along. Within this model we examine two problems, how to organize this real world knowledge, and how it enters into more traditional linguistic questions such as deciding noun phrase reference.
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O objetivo deste trabalho é comparar o método de estimação dos mínimos quadrados ponderados para ajuste de modelos ao semivariograma com o método de tentativa e erro, muito usado na prática, pela técnica de auto-validação "jack- knifing".
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The future of theology libraries is far from clear. Since the nineteenth century, theology libraries have evolved to support the work of theological education. This article briefly reviews the development of theology libraries in North America and examines the contextual changes impacting theology libraries today. Three significant factors that will shape theology libraries in the coming decade are collaborative models of pedagogy and scholarship, globalization and rapid changes in information technology, and changes in the nature of scholarly publishing including the digitization of information. A large body of research is available to assist those responsible for guiding the direction of theology libraries in the next decade, but there are significant gaps in what we know about the impact of technology on how people use information that must be filled in order to provide a solid foundation for planning.
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Sermon preached at Boston University School of Theology during Wednesday Chapel on October 24, 2007
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(adapted from the DSpace Procedures Manual developed by Kalamazoo College Digital Archive)
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Paper presented at the Digital Humanities 2009 conference in College Park, Maryland.
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This is a draft 2 of a discussion paper written for Boston University Libraries
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A working paper written for Boston University Libraries to foster discussion about how to provide better support for BU faculty authors.