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971.
In 2005 ongoing political conflict between the executive and legislative branches of government in Ecuador culminated in a struggle over the judiciary. These events resulted in the dismissal, re-constitution, and dismissal again of the Ecuadorian high court (the Corte Suprema de Justicia) and the impeachment of the president. This paper uses the political crisis surrounding the dismissal of the Ecuadorian Supreme Court of Justice to examine the broader phenomenon of executive branch attacks on the judiciary in South American and Africa. We make three general observations: (1) the longevity of the judiciary alone (time without attack) does not guarantee a sufficiently deep reservoir of diffuse support to protect it from successful efforts at structural change or dissolution, (2) despite previous evidence that multilateral constitutional processes result in increased court independence (Dargent, 2009), we conclude that multi-party institutional arrangements are more vulnerable to the types of crisis that cause them to seek to use courts and their legitimacy to achieve political goals thereby limiting previous gains in independence, and (3) a court's institutional legitimacy is enhanced when it survives political threats from other branches of government. The crisis in Ecuador is used to demonstrate the challenges facing newer democracies with continuing multilateral conflict as well as the utility of thinking about how, why and when political institutions attack high courts and how the judiciary and citizens respond.  相似文献   
972.
973.
The main focus of agricultural, ecological and environmental studies is to develop well designed, cost-effective and efficient sampling designs. Ranked set sampling (RSS) is one method that leads to accomplish such objectives by incorporating expert knowledge to its advantage. In this paper, we propose an efficient sampling scheme, named mixed RSS (MxRSS), for estimation of the population mean and median. The MxRSS scheme is a suitable mixture of both simple random sampling (SRS) and RSS schemes. The MxRSS scheme provides an unbiased estimator of the population mean, and its variance is always less than the variance of sample mean based on SRS. For both symmetric and asymmetric populations, the mean and median estimators based on SRS, partial RSS (PRSS) and MxRSS schemes are compared. It turns out that the mean and median estimates under MxRSS scheme are more precise than those based on SRS scheme. Moreover, when estimating the mean of symmetric and some asymmetric populations, the mean estimates under MxRSS scheme are found to be more efficient than the mean estimates with PRSS scheme. An application to real data is also provided to illustrate the implementation of the proposed sampling scheme.  相似文献   
974.
975.
Abstract

This article provides a background for Comics Librarianship and the sources which can be, and are, used. The author describes the application of FRBR (Functional Requirements for Bibliographic Records) for serials to the cataloging of the comic book format and ways to adapt these methods to flat MARC records, to aid in retrieval of items. Sample records are included for illustration of methods.  相似文献   
976.
Distress related to answering personal survey questions about drug use, suicidal behavior, and physical and sexual abuse were examined in multiple convenience samples of adolescents. Samples varied in consent procedures utilized (active vs. passive parental consent), data collection setting (school vs. juvenile justice), developmental level (middle school vs. high school). Participation rates differed across consent procedures (e.g., 93% with passive vs. 62% with active parental consent). Results indicated that small percentages of adolescents in every sample reported frequently feeling upset while completing the survey (range 2.5% to 7.6%). Age, race, gender, and data collection strategy did not emerge as significant predictors of feeling upset. Instead, as hypothesized, adolescents reporting a history of suicidal ideation or attempt, illicit drug use, or experiences of physical or sexual victimization endorsed more frequent feelings of upset while completing the survey than peers without these experiences. Taken together, however, these sensitive event experiences explained only 6.6% of the variance in adolescents' upset ratings. The scientific and ethical implications of these findings are discussed with regard to adolescent participation in survey research about sensitive topics.  相似文献   
977.
978.
979.
This article examines black Americans' preference for black health care providers. Using data from a national survey, we assess how blacks 'perceptions of discrimination are related to preference for same-race health care providers. Overall, the belief that discrimination is frequent in different-race doctor-patient dyads is associated with greater preference for a same-race provider However; the belief that discrimination occurs regardless of a doctor's race reduces preference for a same-race provider Finally, general perceptions of discrimination are distinct from concerns about personally being treated unfairly, and low personal concern about unfair treatment reduces preference for a same-race provider among those who believe that interpersonal discrimination occurs frequently. These results suggest a complex picture of how perceptions of discrimination influence preferred race of health care provider among blacks in the United States.  相似文献   
980.
Stem cells are capable of self-renewal, differentiation into various lineages, and proliferation; thus, they play critical roles in the functioning and maintenance of many biological systems. However, these unique qualities of stem cells also make them more vulnerable to mutations as the organism ages. The biggest risk factor in cancer development is age, and most scientists believe that cancers partly result from a buildup of mutations in different cell types over time. This accumulation of mutations takes place over the course of a person's lifetime, during which repeated rounds of cell division result in editing errors in the DNA. Genetic alterations can cause changes in the signaling pathways controlling proliferation, differentiation, and apoptosis. In the case of stem cells, such mutations would be passed on to all of the stem cell's progeny, ultimately resulting in a pool of stem cells that feeds neoplastic formation. Studies aiming to identify and characterize these putative cancer stem cells and to understand how they arise will shed light on the process of stem cell aging and its role in cancer.  相似文献   
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