852 resultados para Entanglement measure


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The paper revives a theoretical definition of party coherence as being composed of two basic elements, cohesion and factionalism, to propose and apply a novel empirical measure based on spin physics. The simultaneous analysis of both components using a single measurement concept is applied to data representing the political beliefs of candidates in the Swiss general elections of 2003 and 2007, proposing a connection between the coherence of the beliefs party members hold and the assessment of parties being at risk of splitting. We also compare our measure with established polarization measures and demonstrate its advantage with respect to multi-dimensional data that lack clear structure. Furthermore, we outline how our analysis supports the distinction between bottom-up and top-down mechanisms of party splitting. In this way, we are able to turn the intuition of coherence into a defined quantitative concept that, additionally, offers a methodological basis for comparative research of party coherence. Our work serves as an example of how a complex systems approach allows to get a new perspective on a long-standing issue in political science.

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Little is known about the noble gas abundances in comets. These highly volatile atoms are possible tracers of the history of cometary matter including the thermal evolution. They can help quantify the contribution of cometary impacts to terrestrial oceans and help elucidate on the formation history of comets and their role in the formation and evolution of planetary atmospheres. This paper focuses on argon and the capabilities to measure this noble gas with in situ mass spectrometry at comet 67P/Churyumov–Gerasimenko, the target of the European Space Agency׳s spacecraft Rosetta. Argon may have been detected by remote sensing in a single Oort cloud comet but to date nothing is known about the isotopic abundances of argon in comets. Furthermore, no detection of argon in a Jupiter-family comet has been reported. Comet 67P/Churyumov–Gerasimenko belongs to the group of Jupiter-family comets and originates most likely in the Kuiper belt. Onboard Rosetta is ROSINA/DFMS (Rosetta Orbiter Spectrometer for Ion and Neutral Analysis/Double Focusing Mass Spectrometer). DFMS has unprecedented mass resolution and high sensitivity and is designed to measure isotopic ratios including argon (Balsiger et al., 2007). Argon measurements using the DFMS lab model (identical to the flight model) demonstrate this capability. At very least, this mass spectrometer has the resolution and sensitivity to reduce the upper limit on the argon outgassing rate relative to water by more than three orders of magnitude (for 38Ar). Most likely, ROSINA/DFMS will provide the first detection of argon in a Jupiter-family comet together with the first determination of the ³⁶Ar/³⁸Ar ratio at a comet.

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Empirical research on discrimination is faced with crucial problems stemming from the specific character of its object of study. In democratic societies the communication of prejudices and other forms of discriminatory behavior is considered socially undesirable and depends on situational factors such as whether a situation is considered private or whether a discriminatory consensus can be assumed. Regular surveys thus can only offer a blurred picture of the phenomenon. But also survey experiments intended to decrease the social desirability bias (SDB) so far failed in systematically implementing situational variables. This paper introduces three experimental approaches to improve the study of discrimination and other topics of social (un-)desirability. First, we argue in favor of cognitive context framing in surveys in order to operationalize the salience of situational norms. Second, factorial surveys offer a way to take situational contexts and substitute behavior into account. And third, choice experiments – a rather new method in sociology – offer a more valid method of measuring behavioral characteristics compared to simple items in surveys. All three approaches – which may be combined – are easy to implement in large-scale surveys. Results of empirical studies demonstrate the fruitfulness of each of these approaches.

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Over the last decades, research on narcissism was dominated with a focus on grandiose narcissism as measured by the NPI (Raskin & Terry, 1988), however, recent discussions emphasize the broad range of manifestations of narcissism, in particular more vulnerable aspects. As a result, new questionnaires were developed to cover the full range of these aspects. One example is the Pathological Narcissism Scale (PNI, Pincus et al. 2009), a 52 item questionnaire with seven subscales covering both grandiose and vulnerable aspects. Validation studies show that narcissism as measured with the PNI differs substantially from narcissism as measured with the NPI. Moreover, a discussion concerning the composition of grandiose and vulnerable narcissism has evolved from these data. In our study we demonstrate how scores on narcissism and narcissism subtypes are associated with a broad variety of personality and clinical measures. In a sample of 1837 participants (1240 female, 597 male; mean age 26.8 years) we investigated the correlation patterns of both PNI and NPI subscales with constructs like FFM, aggression, emotions, clinical symptoms, and well-being. Results show that the assignment of subscales to grandiose and vulnerable subtypes are not unambiguous. We therefore conclude that the decision of how to measure narcissism needs further investigation.

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Determining the profit maximizing input-output bundle of a firm requires data on prices. This paper shows how endogenously determined shadow prices can be used in place of actual prices to obtain the optimal input-output bundle where the firm.s shadow profit is maximized. This approach amounts to an application of the Weak Axiom of Profit Maximization (WAPM) formulated by Varian (1984) based on shadow prices rather than actual prices. At these prices the shadow profit of a firm is zero. Thus, the maximum profit that could have been attained at some other input-output bundle is a measure of the inefficiency of the firm. Because the benchmark input-output bundle is always an observed bundle from the data, it can be determined without having to solve any elaborate programming problem. An empirical application to U.S. airlines data illustrates the proposed methodology.

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We propose a nonparametric model for global cost minimization as a framework for optimal allocation of a firm's output target across multiple locations, taking account of differences in input prices and technologies across locations. This should be useful for firms planning production sites within a country and for foreign direct investment decisions by multi-national firms. Two illustrative examples are included. The first example considers the production location decision of a manufacturing firm across a number of adjacent states of the US. In the other example, we consider the optimal allocation of US and Canadian automobile manufacturers across the two countries.

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Various airborne aldehydes and ketones (i.e., airborne carbonyls) present in outdoor, indoor, and personal air pose a risk to human health at present environmental concentrations. To date, there is no adequate, simple-to-use sampler for monitoring carbonyls at parts per billion concentrations in personal air. The Passive Aldehydes and Ketones Sampler (PAKS) originally developed for this purpose has been found to be unreliable in a number of relatively recent field studies. The PAKS method uses dansylhydrazine, DNSH, as the derivatization agent to produce aldehyde derivatives that are analyzed by HPLC with fluorescence detection. The reasons for the poor performance of the PAKS are not known but it is hypothesized that the chemical derivatization conditions and reaction kinetics combined with a relatively low sampling rate may play a role. This study evaluated the effect of absorption and emission wavelengths, pH of the DNSH coating solution, extraction solvent, and time post-extraction for the yield and stability of formaldehyde, acetaldehyde, and acrolein DNSH derivatives. The results suggest that the optimum conditions for the analysis of DNSHydrazones are the following. The excitation and emission wavelengths for HPLC analysis should be at 250nm and 500nm, respectively. The optimal pH of the coating solution appears to be pH 2 because it improves the formation of di-derivatized acrolein DNSHydrazones without affecting the response of the derivatives of the formaldehyde and acetaldehyde derivatives. Acetonitrile is the preferable extraction solvent while the optimal time to analyze the aldehyde derivatives is 72 hours post-extraction. ^

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In the last several decades traditional community health indicators have become ambiguous and lost some of their relevance. During this same period national and international health agencies adopted new expanded definitions of Health that include underlying social determinants. These two influences are responsible for a proliferation of new health indicators and many are constructed from a combination of older mortality measures and available information on morbidity. Problems inherent in attempting to combine these sources of information have produced a situation where some indicators are difficult to calculate at the national level and may not function at all for small communities. What is needed is a relevant measure of the burden of ill health appropriate for smaller populations that is accessible to local health planners. ^ Death records are still the best available population health information. In Europe the burden of health problems is often portrayed using 'premature' death. Health agencies in the United States have moved to adopt Years of Potential Life Lost. Both these regions are also developing systems of 'avoidable' or 'preventable' death as health indicators. This research proposes a method combining these methodologies to produce a relevant indicator portraying the burden of ill health in communities. ^

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Background. Not only has obesity played a role in Texas adults but it is also becoming a large issue among low-income Latino children. In Latino children between 2-5 years of age, the Pediatric Nutrition Surveillance data in 1997 found the prevalence of obesity was 12 percent, highest among all ethnic groups. Children learn what and how to eat from their environment. Despite many mothers being working mothers they are still the principal caregivers and source of influence on their toddler's diet. Self-efficacy, a concept created by Albert Bandura, one's belief that one is capable of performing a behavior needed to reach an intended goal, is increasingly becoming important in nutrition and health education. This study is important to understand the degree of impact that a mother's self-efficacy will have on a child's diet. This is useful knowing if influencing a mother's self-efficacy could improve a child's diet to prevent certain public health issues such as obesity and diabetes. The purpose of this study was to examine nutrition self-efficacy of Latina mothers, focusing on sweets and beverage and if their self-efficacy impacted their child's diet. Methods. The data was collected during July-September 2008. Mothers were recruited from two federally qualified San Antonio health centers. In order to qualify, participants had to be Hispanic with children of toddler age. Mothers were informed of incentives available upon completion. The interview consisted of demographic info, a set of five self-efficacy questions repeated at completion, testing reliability and a 24-hour food recall diary asked of the participant's child's diet. Results. There were 225 mothers who participated between both clinics. The Crohnbach alpha scores for the two different times the self-efficacy questions were asked were .44 corresponding to the first time and .49 for the second time. The three most common beverages reported were milk, juice, and water. The mothers who met or gave their child more milk than recommended by the scientific community, 800mg of calcium/3 cups (24oz) set, had a higher self-efficacy score than those who did not meet the standard at all. Mothers who gave their children more juice than the standard recommends, 4-6oz for children 1-6 years of age, had slightly higher self-efficacy scores than mother's who simply met the standard. In general, the lower the mother's self-efficacy, the more sweets they gave their child and vice versa. Conclusion. This study's Kappa values were adequate and this research showed that Latina mothers did in fact have high self-efficacy. In general some of the children's diets did not reflect the current scientific nutrition recommendations. In order to improve self-efficacy and have an impact on children's diets, the scientific community has a responsibility to make recommendations that are easily understood and can be put into practice. The public health community needs to ensure that we encourage those we serve to be more active in their health and educate them about what constitutes good health and nutrition for both themselves and their children.^

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Background. At present, prostate cancer screening (PCS) guidelines require a discussion of risks, benefits, alternatives, and personal values, making decision aids an important tool to help convey information and to help clarify values. Objective: The overall goal of this study is to provide evidence of the reliability and validity of a PCS anxiety measure and the Decisional Conflict Scale (DCS). Methods. Using data from a randomized, controlled PCS decision aid trial that measured PCS anxiety at baseline and DCS at baseline (T0) and at two-weeks (T2), four psychometric properties were assessed: (1) internal consistency reliability, indicated by factor analysis intraclass correlations and Cronbach's α; (2) construct validity, indicated by patterns of Pearson correlations among subscales; (3) discriminant validity, indicated by the measure's ability to discriminate between undecided men and those with a definite screening intention; and (4) factor validity and invariance using confirmatory factor analyses (CFA). Results. The PCS anxiety measure had adequate internal consistency reliability and good construct and discriminant validity. CFAs indicated that the 3-factor model did not have adequate fit. CFAs for a general PCS anxiety measure and a PSA anxiety measure indicated adequate fit. The general PCS anxiety measure was invariant across clinics. The DCS had adequate internal consistency reliability except for the support subscale and had adequate discriminate validity. Good construct validity was found at the private clinic, but was only found for the feeling informed subscale at the public clinic. The traditional DCS did not have adequate fit at T0 or at T2. The alternative DCS had adequate fit at T0 but was not identified at T2. Factor loadings indicated that two subscales, feeling informed and feeling clear about values, were not distinct factors. Conclusions. Our general PCS anxiety measure can be used in PCS decision aid studies. The alternative DCS may be appropriate for men eligible for PCS. Implications: More emphasis needs to be placed on the development of PCS anxiety items relating to testing procedures. We recommend that the two DCS versions be validated in other samples of men eligible for PCS and in other health care decisions that involve uncertainty. ^

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Loneliness is a pervasive, rather common experience in American culture, particularly notable among adolescents. However, the phenomenon is not well documented in the cross-cultural psychiatric literature. For psychiatric epidemiology to encompass a wide array of psychopathologic phenomena, it is important to develop useful measures to characterize and classify both non-clinical and clinical dysfunction in diverse subgroups and cultures.^ The goal of this research was to examine the cross-cultural reliability and construct validity of a scale designed to measure loneliness. The Roberts Loneliness Scale (RLS-8) was administered to 4,060 adolescents ages 10-19 years enrolled in high schools along either side of the Texas-Tamaulipas border region between the U.S. and Mexico. Data collected in 1988 from a study focusing on substance use and psychological distress among adolescents in these regions were used to examine the operating characteristics of the RLS-8. A sample stratified by nationality and language, age, gender, and grade was used for analysis.^ Results indicated that in general the RLS-8 has moderate reliability in the U.S. sample, but not in the Mexican sample. Validity analyses demonstrated that there was evidence for convergent validity of the RLS-8 in the U.S. sample, but none in the Mexican sample. Discriminant validity of the measures in neither sample could be established. Based on the factor structure of the RLS-8, two subscales were created and analyzed for construct validity. Evidence for convergent validity was established for both subscales in both national samples. However, the discriminant validity of the measure remains unsubstantiated in both national samples. Also, the dimensionality of the scale is unresolved.^ One primary goal for future cross-cultural research would be to develop and test better defined culture-specific models of loneliness within the two cultures. From such scientific endeavor, measures of loneliness can be developed or reconstructed to classify the phenomenon in the same manner across cultures. Since estimates of prevalence and incidence are contingent upon reliable and valid screening or diagnostic measures, this objective would serve as an important foundation for future psychiatric epidemiologic inquiry into loneliness. ^

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The main objective of this study was to attempt to develop some indicators for measuring the food safety status of a country. A conceptual model was put forth by the investigator. The assumption was that food safety status was multifactorily influenced by medico-health levels, food-nutrition programs, and consumer protection activities. However, all these in turn depended upon socio-economic status of the country.^ Twenty-six indicators were reviewed and examined. Seventeen were first screened and three were finally selected, by the stepwise multiple regression analysis, to reflect the food safety status. Sixty-one countries/areas were included in this study.^ The three indicators were life expectancy at birth with multiple correlation coefficient (R2 = 34.62%), adult literacy rate (R2 = 29.66%), and child mortality rate for ages 1-4 (R2 = 9.99%). They showed a cumulative R2 of 57.79%. ^