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41.
Traces the evolution of the certification process for alcohol/drug counselors and explores the issues of time and cost for persons seeking such certification during the 1990s. It is argued that flexibility needs to be built into the certification process and that alternative requirements for obtaining certification should be explored. (0 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
42.
Gail H. Marcus 《Progress in Nuclear Energy》2005,47(1-4):27-31
The mission of the OECD Nuclear Energy Agency (NEA) is to assist its member countries in maintaining and further developing, through international co-operation, the scientific, technological and legal bases required for the safe, environmentally friendly and economical use of nuclear energy for peaceful purposes. In fulfilling that mission, the NEA conducts technical, economic and policy studies in response to the needs and interests of its 28 member countries. In recent years, a number of these studies have addressed various aspects of the next generation of nuclear power plants. This paper will describe some of the major activities recently completed and currently underway that may be of particular interest to the COE-INES program. 相似文献
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44.
Estimation theory is used to derive a new approach to the clustering problem. The new method is a unification of centroid and mode estimation, achieved by considering the effect of spatial scale on the estimator. The result is a multiresolution method which spans a range of spatial scales, giving enhanced robustness both to noise in the data and to changes of scale in the data, by using comparison between scales as a test of cluster validity. Iterative and non-iterative algorithms based on the new estimator are presented and are shown to be more accurate than simple scale-space filtering in identifying and locating the cluster centres from noisy test data. Results from a wide range of applications are used to illustrate the power and versatility of the new method. 相似文献
45.
Bruce E. Maley Mary Gail Engle Suzanne Humphreys Debra A. Vascik Kimberly A. Howes Bruce W. Newton Robert P. Elde 《Microscopy research and technique》1990,15(1):20-33
The monoamines dopamine, noradrenaline, adrenaline, and serotonin as well as the diamine histamine have a widespread distribution in the central nervous system within synaptic terminals and nonsynaptic varicosities. In certain regions of the central nervous system the monoamines are contained in varicosities that have no synaptic specialization associated with them, suggesting a possible neuromodulatory role for some of the monoamines. The majority of monoamine labelled structures are synaptic terminals which are characterized by the presence of small, clear vesicles (40–60 nm) and large, granular vesicles (70–120 nm) within the terminal. A third population of vesicles—small, granular vesicles—which are visible only after histochemical staining, are probably the equivalent of the small, clear vesicles present after either autoradiographic or immunohistochemical labelling. Most monoamine containing terminals contact dendrites and dendritic spines and, less frequently, neuronal somata and other axons. Both asymmetrical and symmetrical membrane specializations are associated with monoaminergic terminals; however, asymmetrical contacts are the most frequent type found. These ultrastructural results indicate that monoamine containing terminals and varicosities in general share many common morphological features, but still have diverse functions. 相似文献
46.
Kitzmiller J.R. Faidley R.W. Fuller R.L. Headifen G.R. Pratap S.B. Spann M.L. Thelen R.F. 《IEEE transactions on magnetics》1991,27(1):50-55
The manufacturing phase of a laboratory-based small-caliber electromagnetic (EM) launcher and compulsator power supply is discussed. The objective of the 29-month program is to develop a compact, lightweight test bed capable of accelerating 32 g masses to 2 km/s at a rate of 10 Hz. Both the power supply and launcher feature significant component design advances which will allow the system to operate at considerably higher energy and power densities than previously demonstrated. The 750 kg compulsator will generate 2.2 kV and the silicon-controlled rectifier (SCR) switch will commutate 386 kA pulses into the 1.6-m long, 0.60 caliber augmented solid armature railgun. The final design and predicted operating characteristics of the compulsator system are described. Overall system performance parameters are reported, including results from the optimization code used to aid in the design of the compulsator system. A system design overview is presented, with emphasis on new materials and state-of-the-art machine components to be used for the first time in a compulsator 相似文献
47.
Martin MD Benton T Bernardo M Woods JS Townes BD Luis H Leitão J Rosenbaum G Castro-Caldas A Pavão I Rue T DeRouen TA 《The Science of the total environment》2007,377(2-3):159-164
Associations between childhood lead exposures and dental caries in children have been reported for over 30 years, with widely varying findings and conclusions, and using measures of lead exposure which ranged from food sources and water to tooth, hair or blood lead concentrations. OBJECTIVES: This study examined the relationship of lead exposure and dental caries in a population of normatively healthy children. METHODS: This cross-sectional study used a population of 507 children aged 8-12 who were participating in a clinical trial of dental materials to examine the relationship between lead and caries. Blood lead concentrations and dental caries were examined for association in both primary and permanent teeth. Because it is possible that neurobehavioral status could be associated with both lead exposure and dental caries prevalence, we also examined neurobehavioral status of the subjects. RESULTS: A gender-specific association (males only) between lead exposure and dental caries was found in primary teeth only. Neurobehavioral measures and IQ were not associated with caries status in this population. CONCLUSIONS: This study did not support neurobehavioral status as mediating any association between lead exposure and caries in a normatively healthy population. A gender-specific association between lead and caries not previously reported was found in primary teeth, and no biological explanation for this has been suggested. We conclude that this study provides only weak evidence, if any, for an association of low-level lead exposure with dental caries. 相似文献
48.
Acid Diffusion into Rice Boluses is Influenced by Rice Type,Variety, and Presence of α‐Amylase
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Yamile A. Mennah‐Govela Gail M. Bornhorst R. Paul Singh 《Journal of food science》2015,80(2):E316-E325
Breakdown of rice during gastric digestion may be influenced by rice structure, presence of salivary α‐amylase, and hydrolysis by gastric acid. During mastication, saliva is mixed with rice, allowing α‐amylase to begin starch hydrolysis. This hydrolysis may continue in the gastric environment depending on the rate at which gastric acid penetrates into the rice bolus. The objective of this study was to determine the acid uptake into rice boluses with and without α‐amylase in saliva. Two types each of brown and white rice (medium and long grain), were formed into a cylindrical‐shaped bolus. Each bolus was sealed on all sides except one to allow one‐dimensional mass transfer, and incubated by immersion in simulated gastric juice at 37 °C under static conditions. Acidity of the boluses was measured by titration after 1 to 96 h of incubation. Effective diffusivity of the gastric juice through the bolus was estimated using MATLAB. Average acidity values ranged from 0.04 mg HCl/g dry matter (medium grain white rice, no incubation) to 10.01 mg HCl/g dry matter (long‐grain brown rice, 72 h incubation). The rice type, presence of α‐amylase, and incubation time all significantly influenced rice bolus acidity (P < 0.001). Effective diffusivity of gastric juice into the bolus was greater in brown rice than in white rice. These results indicate that starch hydrolysis by α‐amylase may continue in the stomach before the gastric acid penetrates the rice bolus, and the rate of acid uptake will depend on the type of rice consumed. 相似文献
49.
Gail E. Tverberg 《Energy》2012,37(1):27-34
Since 2005, (1) world oil supply has not increased, and (2) the world has undergone its most severe economic crisis since the Depression. In this paper, logical arguments and direct evidence are presented suggesting that a reduction in oil supply can be expected to reduce the ability of economies to use debt for leverage. The expected impact of reduced oil supply combined with this reduced leverage is similar to the actual impact of the 2008–2009 recession in OECD countries. If world oil supply should continue to remain generally flat, there appears to be a significant possibility that oil consumption in OECD countries will continue to decline, as emerging markets consume a greater share of the total oil that is available. If this should happen, based on these findings we can expect a continuing financial crisis similar to the 2008–2009 recession including significant debt defaults. The financial crisis may eventually worsen, to resemble a collapse situation as described by Joseph Tainter in The Collapse of Complex Societies (1990) or an adverse decline situation similar to adverse scenarios foreseen by Donella Meadows in Limits to Growth (1972). 相似文献
50.