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11.
As professional psychologists become increasingly involved in shaping health care policy in our nation, it is imperative that they understand the various forces that influence congressional members to enact legislation. This article examines two major issues: (a) Congress's cautious and restrained approach to health care policy and (b) preemption and the relationship between Congress and the states. Understanding these issues will enable psychologists to become more effective representatives of both the professional and societal interests of professional psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
12.
Michel Dorbon Pierre Henri Bigeard Jacques Denis Christian Bernasconi 《Petroleum Science and Technology》1992,10(8):1313-1341
As established by several previous works, nitrogen compounds play a prominent role in the evolution of middle distillates containing cracked components, particularly regarding sediment formation and color evolution.
In a first part, this paper describes and compares stability properties of fuel blends using both an accelerated ageing method at 120°C (248°F ) and long term storage methods at 43°C(110°F) -ASTM 0 4625 - and at ambient temperature. Effectiveness of stabilizing additives is also evaluated. In mixtures containing LCOs, insoluble products are formed progressively during ageings, more or less rapidly according to the chemical constitution of the mixtures.
Then, it reports the complete identification of nitrogen compounds using gas chromatography equipped with a selective nitrogen detector and mass spectrometry showing that in light cycle oils, alkyl indoles and carbazoles are the main families.
Evolution of these compounds was followed kinetically during ageings in absence and presence of additives and alkyl indoles appeared as the moat evolutionary.
It appeared that some additives avoided evolutions of alkyl indoles without preventing sediment formation and color evolution. Oxidation mechanism involving nitrogen compounds should not be the only one to explain the storage evolutions of middle distillates.
Hydrotreatment converts all the alkyl indoles of LCO and prevents coloration end deposits in the storage of the mixtures of steaight-run distillates and LCOs. 相似文献
In a first part, this paper describes and compares stability properties of fuel blends using both an accelerated ageing method at 120°C (248°F ) and long term storage methods at 43°C(110°F) -ASTM 0 4625 - and at ambient temperature. Effectiveness of stabilizing additives is also evaluated. In mixtures containing LCOs, insoluble products are formed progressively during ageings, more or less rapidly according to the chemical constitution of the mixtures.
Then, it reports the complete identification of nitrogen compounds using gas chromatography equipped with a selective nitrogen detector and mass spectrometry showing that in light cycle oils, alkyl indoles and carbazoles are the main families.
Evolution of these compounds was followed kinetically during ageings in absence and presence of additives and alkyl indoles appeared as the moat evolutionary.
It appeared that some additives avoided evolutions of alkyl indoles without preventing sediment formation and color evolution. Oxidation mechanism involving nitrogen compounds should not be the only one to explain the storage evolutions of middle distillates.
Hydrotreatment converts all the alkyl indoles of LCO and prevents coloration end deposits in the storage of the mixtures of steaight-run distillates and LCOs. 相似文献
13.
Silvano Dal Zilio Denis Lugiez 《Applicable Algebra in Engineering, Communication and Computing》2006,17(5):337-377
XML documents may be roughly described as unranked, ordered trees and it is therefore natural to use tree automata to process or validate them. This idea has already been successfully applied in the context of Document Type Definition (DTD), the simplest standard for defining document validity, but additional work is needed to take into account XML Schema, a more advanced standard, for which regular tree automata are not satisfactory. In this paper, we introduce Sheaves Logic (SL), a new tree logic that extends the syntax of the – recursion-free fragment of – W3C XML Schema Definition Language (WXS). Then, we define a new class of automata for unranked trees that provides decision procedures for the basic questions about SL: model-checking; satisfiability; entailment. The same class of automata is also used to answer basic questions about WXS, including recursive schemas: decidability of type-checking documents; testing the emptiness of schemas; testing that a schema subsumes another one.This work was partially supported by the French government research grant ACI TRALALA and by IST Global Computing Profundis. 相似文献
14.
An approach to solve numerically transport equations for plasmas with spontaneously arising and arbitrarily located transport barriers, regions with a strongly reduced transfer of energy, is proposed. The transport equations are written in a form conserving heat flux and solved numerically by using piecewisely exact analytical solutions of linear differential equations. Compared to standard methods, this approach allows to reduce significantly the number of operations required to obtain a converged solution with a heat conductivity changing abruptly at a critical temperature gradient and to use large time steps in modeling the formation and dynamics of transport barriers. Computations for the tokamak JET are done. 相似文献
15.
Identification of the reasons for failures of process plant machines is the first step in obtaining increased reliability. Weibull analysis of the service life obtained from maintenance records requires a minimum of only five incidents and provides an insight into the failure mechanism. Two examples are given where Weibull analysis of maintenance records helped identify the cause of failure and was instrumental in achieving enhanced reliability of process plant machines. 相似文献
16.
The case of a child who presented with severe rhabdomyolysis associated with renal failure after a viper bite is reported. Rhabdomyolysis is a serious complication resulting from systemic envenomation and is uncommon after viper bites in Europe. It may be due to oedema, myotoxic agents and haemorrhagic factors and may be responsible for two types of potentially fatal complications, i.e. acute renal failure and hyperkalaemia. The present case highlights the need to investigate routinely for rhabdomyolysis after viper bites. Antivenom therapy is recommended as soon as signs of envenomation are present, without waiting for the onset of complications. 相似文献
17.
We present a multimodal document alignment framework, which highlights existing alignment relationships between documents that are discussed and recorded during multimedia events such as meetings. These relationships that should help indexing the archives of these events are detected using various techniques from natural language processing and information retrieval. The main alignment strategies studied are based on thematic, quotation and reference relationships. At the analysis level, the alignment framework was applied at several levels of granularity of documents, requiring specific document segmentation techniques. Our framework that is language independent was evaluated on corpora in French and English, including meetings and scientific presentations. The satisfactory evaluation results obtained at several stages show the importance of our approach in bridging the gap between meeting documents, independently from the language and domain. They highlight also the utility of the multimodal alignment in advanced applications, e.g. multimedia document browsing, content-based / temporal-based searching, etc. 相似文献
18.
Bruno Gabel Denis Thiéry Vaclav Suchy Frédéric Marion-Poll Peter Hradsky Pavel Farkas 《Journal of chemical ecology》1992,18(5):693-701
The European grapevine moth (EGVM),Lobesia botrana, is a major pest of grapes in Europe. Females are attracted to a nonhost plant: tansy (Tanacetum vulgare L.), which is a common weed in Slovakian vineyards. A steam distillate extract of tansy flowers was analyzed by means of a GC-EAG technique to screen constituents detected by the olfactory receptors of EGVM females. From more than 200 GC peaks, nine peaks corresponding to monoterpenoids released an EAG response in more than 70% of the females (N=15):p-cymene,d-limonene,-thujene,-thujone,-thujone, thujyl alcohol, terpinene-4-ol, (Z)-verbenol, and piperitone. The steam distillate of tansy as well as a synthetic blend of identified compounds released consistent attraction in a field cage. The use of nonhost plants and host plant odors in integrated pest management is discussed. 相似文献
19.
Wax esters were isolated from commercial orange roughy (Hoplostethus atlanticus) oil by column chromatography and fractionated by argentation thin layer chromatography. Following transesterification, the
resultant fatty acid methyl esters and fatty alcohols were analyzed by gas chromatography. both acyl- and alkyl-moieties were
mainly of the monoene structure within the 16∶1–22∶1 range. After derivatization, the positions of the double bonds of even
numbered fatty acid and fatty alcohol isomers were located by chromatography-mass spectrometry and compared.
Results of these positional analyses indicate that the primary desaturation reactions takes place in the Δ9 position of pre-existing
(C14 to C24) acyl chains. It is proposed that acyl components from 18∶1 are subjected to chain elongation to form a mixture of 24∶1 isomers
as the final product. Apart from the 24∶1 acyl moiety of the wax esters, in which the double bond was almost exclusively in
the Δ15 position, de novo biosynthetic reactions on acids and alcohols appear to yield related acyl- and alkyl-moieties of
resynthesized wax esters. 相似文献
20.
Arkadev Chattopadhyay Ricard Gavaldà Kristoffer Arnsfelt Hansen Denis Thérien 《Theory of Computing Systems》2014,55(2):404-420
Boolean functions that have constant degree polynomial representation over a fixed finite ring form a natural and strict subclass of the complexity class ACC0. They are also precisely the functions computable efficiently by programs over fixed and finite nilpotent groups. This class is not known to be learnable in any reasonable learning model. In this paper, we provide a deterministic polynomial time algorithm for learning Boolean functions represented by polynomials of constant degree over arbitrary finite rings from membership queries, with the additional constraint that each variable in the target polynomial appears in a constant number of monomials. Our algorithm extends to superconstant but low degree polynomials and still runs in quasipolynomial time. 相似文献