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301.
With revenues of more than $200 billion and a growth rate of 13% per year — software is one of the world's fastest growing industries. It is also one of the most vulnerable. The lack of awareness in the industry regarding software protection remains a great mystery. Even the humblest inventor will seek to first protect before he proceeds with his product or at least will try to find out what protection he might obtain. Not so, it would appear in the software business. Yet the issues of ownership and infringement are of every day importance to those involved in this sector. 相似文献
302.
Heatherton Todd F.; Herman C. Peter; Polivy Janet; King Gillian A.; McGree Sheila T. 《Canadian Metallurgical Quarterly》1988,97(1):19
In this article we examine alleged conceptual and psychometric deficiencies of the Restraint Scale, an instrument intended to identify chronic dieters. These deficiencies include the confounding of restraint with disinhibition, the inapplicability of the scale to obese samples, problems with the factor structure of the scale, and difficulties in completing the scale. We argue that these alleged deficiencies are in most cases chimerical and that the Restraint Scale remains the most useful tool for examining behavioral and other dieter/nondieter differences. Proposed alternatives to the Restraint Scale are examined and found to be inadequate as replacements, although they may be useful for certain purposes. Closer attention to the intended purpose of such instruments may serve to dispel controversy and confusion. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
303.
Using the Weissenberg rheogoniometer, a technique has been developed which facilitates the measurement of shear stress data and which substantially overcomes the problem of sample loss that normally occurs at high shear rates. Using this technique, the apparent viscosities of PVC pastes based upon four different PVC paste polymers plasticized with dialphyl phthalate have been determined at a number of shear rates up to 9000 sec?1 and the viscosity aging characteristics of these paste polymers have been compared. The effect of several common plasticizers upon PVC paste viscosity and viscosity aging have been studied at shear rates of the order of 10 sec?1 and 1000 sec?1. 相似文献
304.
Miltefosine (hexadecylphosphocholine, HePC) is the first effective oral agent for the treatment of visceral leishmaniasis.
The characteristics of HePC incorporation into the human intestinal epithelial cell line Caco-2 were investigated in order
to understand its oral absorption mechanism. The results provide evidence for the involvement of a carrier-mediated mechanism,
since the association of HePC at the apical pole of Caco-2 cells was (1) saturable as a function of time with a rapid initial
incorporation over 5 min followed by a more gradual increase; (2) saturable as a function of concentration over the range
studied (2–200 μM) with a saturable component which followed Michaelis–Menten kinetics (apparent K
m 15.7 μmol/L, V
max 39.2 nmol/mg protein/h) and a nonspecific diffusion component; (3) partially inhibited by low temperature and ATP depletion,
indicating the temperature and energy-dependence of the uptake process. Moreover, we demonstrated, by an albumin back-extraction
method, that HePC is internalized via translocation from the outer to the inner leaflet of the plasma membrane and that HePC
may preferentially diffuse through intact raft microdomains. In conclusion, our results suggest that incorporation of HePC
at the apical membrane of Caco-2 cells may occur through a passive diffusion followed by a translocation in the inner membrane
leaflet through an active carrier-mediated mechanism. 相似文献
305.
An understanding of the ways in which work coordination is achieved in practice is essential to the development of effective CSCW technologies. However, previous studies are limited in their focus on small, self-contained work groups. In this analysis of work coordination in a hospital context, a broader perspective was adopted, allowing examination of activities across time, group and location. The use of a relevant structured methodology and a focus on deviations from formal procedures enabled the consideration of a range of contextual factors in interaction: Important aspects of work coordination to emerge included: status influences on the effectiveness of working practices; the social and political uses of information; conflicts between work goals and between motivations for coordinating activities; the role of informal practices; and the use of formal procedures to regulate inter-group relations. The implications of these issues for CSCW design in the hospital context are illustrated. 相似文献
306.
307.
Robert F. Baldwin Stephen C. Trombulak Mark G. Anderson Gillian Woolmer 《Landscape and urban planning》2007,80(4):404-411
Existing roads have far-reaching effects on biodiversity, and therefore road network expansion is of critical concern to conservation planning. Road density trend analysis is often too coarse and assumes homogeneous landscapes, whereas spatial transition probability analysis captures landscape variability typical of ecoregions. Simple models for projecting road network growth will assist planning agencies and conservation organizations to guide protection efforts. We investigate growth of regular public roads in the State of Maine over a 17-year historical period, and then use the best-selected (AIC) logistic regression model to validate and then project spatial probability of future roads to the Northern Appalachian/Acadian ecoregion. Nearly 2000 km of new roads were constructed in settled landscapes in Maine 1986–2003, influencing 37,000 ha of adjacent habitats. The majority (93.5%) of the new roads performed local functions and were short (<1/3 km in length), characterized as residential roads typical of sprawl. The best-selected logit model [dwelling density (+), elevation (−), distance to urban area (−), distance to existing primary/secondary highway (−)] captured 84% of reserved new road points in Maine, and only 27% of random points at the >0.5 probability level. The projected model forecasts 0.5 million km of new residential public roads in the Northern Appalachian/Acadian ecoregion for the next two decades, suggesting that cumulative effects of residential road network expansion are a serious region-scale biodiversity threat. 相似文献
308.
This study set out to determine if ultimate pH (pHu) affected the performance of intracellular small heat shock protein and endopeptidase dynamics in muscle during beef ageing. Longissimus dorsi muscles from 39 Angus or Limousin × Angus bulls were examined to see if pHu achieved at 22 h post mortem (rigor) affected tenderness and water holding capacity of beef. Samples were segregated into three pHu groups termed high (pH > 6.3), intermediate (5.7 < pH < 6.3) and low (pH < 5.7) pHu beef. More than 30% of bull beef did not achieve acceptable tenderness at 8 days post mortem with this ageing regime. No significant differences in calpain or cathepsin enzyme levels due to meat pH were observed until after 22 h post mortem, but low pHu beef had elevated caspase 3/7 activity soon after slaughter. At 22 h post mortem, greater levels of μ-calpain enzyme were found in the high and intermediate pHu beef and cathepsin B levels were superior in the low pHu beef after 2 days post mortem. Different rates of desmin and troponin T protein degradation were also observed in aged bull beef. Both proteins were degraded within 6 h post mortem for high pHu beef, but took >3 days post mortem for intermediate pHu beef. High levels of alpha β-crystallin (aβC) at 22 h post mortem coincided with delayed muscle protein degradation for low pHu beef. Our results support the hypothesis that aβC shields myofibrils and buffers against endopeptidase degradation of beef structure during ageing. 相似文献