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排序方式: 共有953条查询结果,搜索用时 15 毫秒
91.
This paper presents an integrative model developed this past year by the Building Construction (BC) Department at Virginia Tech (VT), designed to help each student master the competencies necessary to succeed in the 21st Century as a building constructor in a changing global market-place. The curriculum described in this paper presents a dynamic, practical, applied academic model; balances the construction education concepts of practical experience based knowledge with academic inquiry; integrates people and communication skills with the pragmatic building construction skills; and provides a construction program that maintains a strong identity positioned between architecture and engineering. Strategically this task was accomplished by weaving vertical and horizontal integration into the BC curriculum at Virginia Tech. Results of this first year are presented, including lessons learned, external evaluations, and recommendations for adaptation.  相似文献   
92.
Rethinking Project Management: Researching the actuality of projects   总被引:2,自引:0,他引:2  
This paper puts forth the somewhat controversial position that what is needed to improve project management in practice is not more research on what should be done or the frequency and/or use of traditional project management practices. We argue that while a great deal is written about traditional project management we know very little about the “actuality” of project based working and management. This paper formulates a research approach that takes seriously practitioner’s lived experience of projects. We explore the ontological, epistemological and methodological assumptions underlying this kind of research and provide examples of some project management research originating from this perspective. We conclude by summarizing the findings from these studies and providing insights into the map ahead for future such research. In this kind of work the attention is refocused on praxis, on context-dependent judgement, on situational ethics and on reflexivity which enables social actors to see how power actually functions in context.  相似文献   
93.
The present research examines episodes of favor exchange among peer employees. We posit that favor receivers' and favor givers' commitment to their exchange relationships with one another will be accounted for by different factors. As predicted, in 2 different organizational contexts, receivers' commitment to their relationships with givers was found to be more related to their judgments of the givers' interactional justice when performing the favor, whereas givers' commitment to their relationships with receivers was shown to be more associated with their judgments of the favorability of the outcomes associated with the favor that they performed. The implications of these findings for how givers and receivers can better manage favor exchange, and hence their relationships with each other, are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
94.
Hypertonic saline (HS) administered intraperitoneal/ly (ip) reduced the intake of sucrose solution infused intraorally in tube-fed decerebrate rats, as it did in control animals. Similarly, either ip or intravenous HS markedly decreased the intake of laboratory chow by neurologically intact control rats. These observations complement recent findings that lesions of putative osmoreceptors in the ventral diencephalon, which eliminate thirst and blunt pituitary secretion of vasopressin and oxytocin in response to HS in rats, have no apparent effect on the HS-induced inhibition of food intake. Taken together they support previous studies indicating an important role for the caudal brainstem in the central control of food intake and suggest that such brainstem control may also include the inhibition of food intake induced by acute hyperosmolality. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
95.
A considerable proportion of cases of myeloproliferative and lymphoproliferative disorders exhibit renal involvement. However, it is unclear whether the cytologic features, immunophenotype or grade of malignancy of the cells infiltrating the kidney differ from those of the primary tumor. This study was performed on 120 autopsy cases with the following diagnoses: acute myelogenous leukemia (AML, n = 22; subtypes M1 + M2, n = 12, subtype M4, n = 10), chronic myelogenous leukemia (CML, n = 7), agnogenic myeloid metaplasia/myelofibrosis (AMM/MF, n = 6), acute lymphocytic leukemia (ALL, n = 6), chronic lymphocytic leukemia (CLL, n = 9), other low-grade non-Hodgkin's lymphomas (low-grade NHL, n = 24), high-grade NHL (n = 21) and multiple myeloma (MM, n = 25). Renal involvement was investigated by light microscopy and immunohistochemistry. It was found in 34% of the cases, and was most common in ALL (83%) and low-grade NHL (50%) and least common in high-grade NHL (10%) and MM (12%). Dense infiltration of almost the entire kidney was most commonly seen in AML, low-grade NHL and ALL. Infiltration was bilateral and involved both the cortex and medulla in the majority of cases. When involvement of other organs was compared with that of the kidney, the lung was found to be involved in approximately the same number of cases, but liver involvement was more common and heart involvement less common. Reactive lymphocytic infiltration of the kidney was found in 18 of the 120 cases (15%), and was distinguished from scanty tumorous infiltration by immunohistochemical staining. No major phenotypical differences were found between the tumor cells infiltrating the kidney and those of the primary tumors in the bone marrow or lymph nodes. However, in one case of CML, the cells infiltrating the kidney were negative for KP1 and chloroacetate esterase, but could be identified by reactivity for CD34. The grade of malignancy in NHL was similar in both the nodal and renal manifestations.  相似文献   
96.
97.
This commmunication describes some current applications tions of adaptive filtering to the processing of microwave Doppler signals for heart rate monitoring. The problem has been approached in the past using signal processing techniques such as peak detection or autocorrelation. These methods either require large amounts of data or tend to be unreliable. This communication utilizes some recent techniques used in speech processing and applies them to heartbeat detection, thus allowing on-line processing of sampled microwave heart signals. The presentation includes a model for the signal, brief discussions of the algorithms evaluated, and qualitative analysis of performance compared to EKG measurements.  相似文献   
98.
We have built a Decision Support System (DSS) which can to aid strategic management within the industry in making vital decisions in relation to Customer and Network profiles. This enables managers in the respective areas within the industry to fully utilise the vast amounts of data available to make projections and decisions in relation to utilisation of valuable resources. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
99.
Prenylation is a post‐translational modification wherein an isoprenoid group is attached to a protein substrate by a protein prenyltransferase. Hundreds of peptide sequences are in vitro substrates for protein farnesyltransferase (FTase), but it remains unknown which of these sequences can successfully compete for in vivo prenylation. Translating in vitro studies to predict in vivo protein farnesylation requires determining the minimum reactivity needed for modification by FTase within the cell. Towards this goal, we developed a reporter protein series spanning several orders of magnitude in FTase reactivity as a calibrated sensor for endogenous FTase activity. Our approach provides a minimally invasive method to monitor changes in cellular FTase activity in response to environmental or genetic factors. Determining the reactivity “threshold” for in vivo prenylation will help define the prenylated proteome and identify prenylation‐dependent pathways for therapeutic targeting.  相似文献   
100.
Access to lead compounds with defined molecular targets continues to be a barrier to the translation of natural product resources. As a solution, we developed a system that uses discrete, recombinant proteins as the vehicles for natural product isolation. Here, we describe the use of this functional chromatographic method to identify natural products that bind to the AAA+ chaperone, p97, a promising cancer target. Application of this method to a panel of fungal and plant extracts identified rheoemodin, 1‐hydroxydehydroherbarin, and phomapyrrolidone A as distinct p97 modulators. Excitingly, each of these molecules displayed a unique mechanism of p97 modulation. This discovery provides strong support for the application of functional chromatography to the discovery of protein modulators that would likely escape traditional high‐throughput or phenotypic screening platforms.  相似文献   
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