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251.
The U.S. Census Bureau reports that Hispanics are the country's largest and fastest growing minority, representing about 14.4 percent of the population in 2005 (Census Bureau 2006b). By 2050, Hispanics will account for an estimated 24.4 percent of the population--or 1 in every 4 persons in the United States (Census Bureau 2004, Table 1 a). The Hispanic population tends to be younger than the overall population and currently represents a relatively small but growing fraction of the Social Security beneficiary population. The representation of Hispanics in the Supplemental Security Income (SSI) program, however, approximates that of their representation in the overall population. This article compares the Hispanic population with the overall population along several dimensions, with a particular focus on the Social Security beneficiary and SSI recipient populations. Data are drawn mainly from the 2005 Public Use Microdata Sample of the American Community Survey (ACS PUMS), a relatively new data source with a rich set of economic and demographic variables. Fully implemented nationwide for the first time in 2005, the ACS became the largest household survey in the United States with a sample of almost 3 million addresses. The analysis using the ACS finds that the Hispanic population is significantly different from the general population, particularly in the areas of age distribution, educational attainment, and economic well-being. Compared with the general population, the Hispanic segment is younger and is characterized by lower levels of educational attainment and a higher rate of poverty. The Hispanic Social Security beneficiary population also differs significantly from the general beneficiary population in the same areas. In contrast, the Hispanic and general SSI populations are more comparable with regard to age and economic status and differ significantly only with regard to education.  相似文献   
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This paper presents a quantitative and qualitative content analysis of Twitter posts mentioning Queensland Premier Anna Bligh and Australian Prime Minister Julia Gillard during the 2011 Queensland flood crisis. The contrast in the perceived styles of the two leaders is analysed using the theory of transformational leadership as a framework. The implications for effective leadership communication in a crisis are discussed, notably, strategies for instilling pride and gaining respect and trust. The study also highlights the emerging role of Twitter in setting the media agenda at times of fast‐breaking news. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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This article explores the attitudes of officials in the upper echelons in Chinese provincial and local government toward the origins of administrative reform. The authors examine the somewhat dichotomous argument that reform imitates the West or is indigenous and contend that both influences are present. Data drawn from a survey of party cadres and government officials show that cultural factors (time in government, overall knowledge of administrative reforms, together with familiarity with the move from a planned system of government to a market economy) and structural variables (upper echelon and familiarity with business management techniques) are correlated with learning from the West. Cadres and officials who spend more time managing outward and those who are familiar with performance assessment do not learn from the West. The theoretical and research implications of these findings—that learning from the West is an important influence on the adoption of administrative reforms in China—are discussed.  相似文献   
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Objectives  

This study tests whether juveniles’ responses on sensitive topics such as self-reported delinquency, victimization, and substance use are comparable when teachers versus external persons supervise students while filling out online questionnaires.  相似文献   
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Das ABGB wurde am 1. 6. 1811 kundgemacht und ist am 1. 1. 1812 in Kraft getreten. Aus Anlass seines 200. Jahrestages wurden zahlreiche Veranstaltungen abgehalten. Der folgende Beitrag beruht auf einem Vortrag, der anl?sslich der Pr?sentation der Festschrift 200 Jahre ABGB bei einer vom ?sterreichischen Juristentag und dem Bundesministerium für Justiz organisierten Festveranstaltung gehalten wurde. Der Verfasser greift darin den erstmals vor 100 Jahren von Franz Klein formulierten Topos von der Lebenskraft des ABGB auf und versucht eine kritische Bewertung aus heutiger Perspektive.  相似文献   
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Abstract: Forensic laboratories around the world have seen an increase in the number of drug seizures containing methorphan. Levomethorphan is a narcotic and a controlled substance, and its enantiomer dextromethorphan is an antitussive agent used in over‐the‐counter medications. For the forensic analysis of seized drugs containing methorphan, it is important to report the stereochemical composition of the drug. Ideally, a method based on common forensic laboratory instrumentation is desirable. The use of the chiral derivatizing agent (?)‐menthyl chloroformate followed by routine gas chromatography–mass spectrometry analysis of the derivative was shown to successfully determine the stereochemical composition of methorphan. This approach was applied to a street seizure containing methorphan proving that it was pure dextromethorphan. The derivatives of dextro‐ and levomethorphan were subjected to mass spectroscopic and nuclear magnetic resonance analysis, which confirmed that the structure of the derivatives remained unchanged as a result of the derivatization process.  相似文献   
260.
Mephedrone is a synthetic derivative of cathinone which is becoming more common on the recreational drug market. Several intoxications following mephedrone abuse have been reported though published papers have focused essentially on analytical approaches for biological fluids and only one has involved a hair sample. After the development and validation of a new method, the first series of positive results for mephedrone in hair specimens is reported here. After decontamination of the hair strand in methylene chloride, hair segments were cut into small pieces with scissors, weighed and incubated overnight in Soerensen buffer pH 7.0 in the presence of deuterated 3,4-methylenedioxymethamphetamine (MDMA) at 40°C. The incubation medium was extracted using ethyl acetate after alkalinisation with 1N sodium hydroxide (NaOH). Before injection, the dry extract was derivatized using a mixture of heptafluorobutyric anhydride/ethyl acetate (100:50, v/v), evaporated and dissolved in ethyl acetate (25μl). After introduction of 1μl of the extract onto a splitless injector, chromatographic separation was achieved on a HP 6890 gas chromatograph equipped with a 5-MS capillary column. Detection was achieved in single ion monitoring mode (m/z 254-119-210 for mephedrone, m/z 258-213 for MDMA-d5) using a 5973 MSD operating in electron impact mode. Sixty-seven hair specimens were tested for mephedrone. Thirteen of them were found positive for mephedrone with concentrations ranging from 0.2 to 313.2ng/mg with a mean concentration of 26.8ng/mg. It was difficult to compare our findings due to a lack of reference data, nevertheless mephedrone seems well incorporated into hair (concentrations in the ng/mg range) like other stimulant drugs such as amphetamines or cocaine. The aim of this work was to develop a specific and accurate method for mephedrone analysis in hair specimens and its application to a large number of samples (n=67). The developed analytical method appears sensitive enough to reveal occasional to regular use of mephedrone.  相似文献   
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