420 research outputs found
Quality as praxis: A tool for formative meta-evaluation
Summative meta-evaluation is known to be more commonly practiced than formative meta-evaluation. While evaluation theorists speak to the importance of formative meta-evaluation, examples of how to do this are rarely specified in the evaluation literature. This paper aims to (1) further explore formative meta-evaluation as a means for quality assurance, with implications for both developing the capacity of evaluators and for advancing evaluation as a field of practice; and (2) to present a model with the intent to move toward a more deliberate formative quality evaluation practice. Discussion focuses on the relationship between evaluator and commissioner and how the development and use of a deliberate approach to formative meta-evaluation, through examination of the proposed model, can lead to a more egalitarian and inclusive approach to defining and promoting evaluation quality. Lastly, formative meta-evaluation is discussed as an important tool for evaluators in exercising professional judgment and for taking an active role in advancing the evaluation field
A RADIOAUTOGRAPHIC STUDY OF GLYCERIDE SYNTHESIS IN VIVO DURING INTESTINAL ABSORPTION OF FATS AND LABELED GLUCOSE
Quality as praxis
Summative meta-evaluation is known to be more commonly practiced than formative meta-evaluation. While evaluation theorists speak to the importance of formative meta-evaluation, examples of how to do this are rarely specified in the evaluation literature. This paper aims to (1) further explore formative meta-evaluation as a means for quality assurance, with implications for both developing the capacity of evaluators and for advancing evaluation as a field of practice; and (2) to present a model with the intent to move toward a more deliberate formative quality evaluation practice. Discussion focuses on the relationship between evaluator and commissioner and how the development and use of a deliberate approach to formative meta-evaluation, through examination of the proposed model, can lead to a more egalitarian and inclusive approach to defining and promoting evaluation quality. Lastly, formative meta-evaluation is discussed as an important tool for evaluators in exercising professional judgment and for taking an active role in advancing the evaluation field
HLA-A Confers an HLA-DRB1 Independent Influence on the Risk of Multiple Sclerosis
A recent high-density linkage screen confirmed that the HLA complex contains the strongest genetic factor for the risk of multiple sclerosis (MS). In parallel, a linkage disequilibrium analysis using 650 single nucleotide polymorphisms (SNP) markers of the HLA complex mapped the entire genetic effect to the HLA-DR-DQ subregion, reflected by the well-established risk haplotype HLA-DRB1*15,DQB1*06. Contrary to this, in a cohort of 1,084 MS patients and 1,347 controls, we show that the HLA-A gene confers an HLA-DRB1 independent influence on the risk of MS (Pβ=β8.4Γ10β10). This supports the opposing view, that genes in the HLA class I region indeed exert an additional influence on the risk of MS, and confirms that the class I allele HLA-A*02 is negatively associated with the risk of MS (ORβ=β0.63, Pβ=β7Γ10β12) not explained by linkage disequilibrium with class II. The combination of HLA-A and HLA-DRB1 alleles, as represented by HLA-A*02 and HLA-DRB1*15, was found to influence the risk of MS 23-fold. These findings imply complex autoimmune mechanisms involving both the regulatory and the effector arms of the immune system in the triggering of MS
Importance of Human Leukocyte Antigen (HLA) Class I and II Alleles on the Risk of Multiple Sclerosis
Multiple sclerosis (MS) is a complex disease of the central nervous system of unknown etiology. The human leukocyte antigen (HLA) locus on chromosome 6 confers a considerable part of the susceptibility to MS, and the most important factor is the class II allele HLA-DRB1*15:01. In addition, we and others have previously established a protective effect of HLA-A*02. Here, we genotyped 1,784 patients and 1,660 healthy controls from Scandinavia for the HLA-A, HLA-B, HLA-C and HLA-DRB1 genes and investigated their effects on MS risk by logistic regression. Several allele groups were found to exert effects independently of DRB1*15 and A*02, in particular DRB1*01 (ORβ=β0.82, pβ=β0.034) and B*12 (including B*44/45, ORβ=β0.76, pβ=β0.0028), confirming previous reports. Furthermore, we observed interaction between allele groups: DRB1*15 and DRB1*01 (multiplicative: ORβ=β0.54, pβ=β0.0041; additive: APβ=β0.47, pβ=β4Γ10β06), DRB1*15 and C*12 (multiplicative: ORβ=β0.37, pβ=β0.00035; additive: APβ=β0.58, pβ=β2.6Γ10β05), indicating that the effect size of these allele groups varies when taking DRB1*15 into account. Analysis of inferred haplotypes showed that almost all DRB1*15 bearing haplotypes were risk haplotypes, and that all A*02 bearing haplotypes were protective as long as they did not carry DRB1*15. In contrast, we found one class I haplotype, carrying A*02-C*05-B*12, which abolished the risk of DRB1*15. In conclusion, these results confirms a complex role of HLA class I and II genes that goes beyond DRB1*15 and A*02, in particular by including all three classical HLA class I genes as well as functional interactions between DRB1*15 and several alleles of DRB1 and class I genes
First Is Best
We experience the world serially rather than simultaneously. A century of research on human and nonhuman animals has suggested that the first experience in a series of two or more is cognitively privileged. We report three experiments designed to test the effect of first position on implicit preference and choice using targets that range from individual humans and social groups to consumer goods. Experiment 1 demonstrated an implicit preference to buy goods from the first salesperson encountered and to join teams encountered first, even when the difference in encounter is mere seconds. In Experiment 2 the first of two consumer items presented in quick succession was more likely to be chosen. In Experiment 3 an alternative hypothesis that first position merely accentuates the valence of options was ruled out by demonstrating that first position enhances preference for the first even when it is evaluatively negative in meaning (a criminal). Together, these experiments demonstrate a βfirst is bestβ effect and we offer possible interpretations based on evolutionary mechanisms of this βboundβ on rational behavior and suggest that automaticity of judgment may be a helpful principle in clarifying previous inconsistencies in the empirical record on the effects of order on preference and choice
Early B-cell Factor gene association with multiple sclerosis in the Spanish population
BACKGROUND: The etiology of multiple sclerosis (MS) is at present not fully elucidated, although it is considered to result from the interaction of environmental and genetic susceptibility factors. In this work we aimed at testing the Early B-cell Factor (EBF1) gene as a functional and positional candidate risk factor for this neurological disease. Axonal damage is a hallmark for multiple sclerosis clinical disability and EBF plays an evolutionarily conserved role in the expression of proteins essential for axonal pathfinding. Failure of B-cell differentiation was found in EBF-deficient mice and involvement of B-lymphocytes in MS has been suggested from their presence in cerebrospinal fluid and lesions of patients. METHODS: The role of the EBF1 gene in multiple sclerosis susceptibility was analyzed by performing a case-control study with 356 multiple sclerosis patients and 540 ethnically matched controls comparing the EBF1 polymorphism rs1368297 and the microsatellite D5S2038. RESULTS: Significant association of an EBF1-intronic polymorphism (rs1368297, A vs. T: p = 0.02; OR = 1.26 and AA vs. [TA+TT]: p = 0.02; OR = 1.39) was discovered. This association was even stronger after stratification for the well-established risk factor of multiple sclerosis in the Major Histocompatibility Complex, DRB1*1501 (AA vs. [TA+TT]: p = 0.005; OR = 1.78). A trend for association in the case-control study of another EBF1 marker, the allele 5 of the very informative microsatellite D5S2038, was corroborated by Transmission Disequilibrium Test of 53 trios (p = 0.03). CONCLUSION: Our data support EBF1 gene association with MS pathogenesis in the Spanish white population. Two genetic markers within the EBF1 gene have been found associated with this neurological disease, indicative either of their causative role or that of some other polymorphism in linkage disequilibrium with them
Association between Protective and Deleterious HLA Alleles with Multiple Sclerosis in Central East Sardinia
The human leukocyte antigen (HLA) complex on chromosome 6p21 has been unambiguously associated with multiple sclerosis (MS). The complex features of the HLA region, especially its high genic content, extreme polymorphism, and extensive linkage disequilibrium, has prevented to resolve the nature of HLA association in MS. We performed a family based association study on the isolated population of the Nuoro province (Sardinia) to clarify the role of HLA genes in MS. The main stage of our study involved an analysis of the ancestral haplotypes A2Cw7B58DR2DQ1 and A30Cw5B18DR3DQ2. On the basis of a multiplicative model, the effect of the first haplotype is protective with an odds ratio (OR)β=β0.27 (95% confidence interval CI 0.13β0.57), while that of the second is deleterious, OR 1.78 (95% CI 1.26β2.50). We found both class I (A, Cw, B) and class II (DR, DQ) loci to have an effect on MS susceptibility, but we saw that they act independently from each other. We also performed an exploratory analysis on a set of 796 SNPs in the same HLA region. Our study supports the claim that Class I and Class II loci act independently on MS susceptibility and this has a biological explanation. Also, the analysis of SNPs suggests that there are other HLA genes involved in MS, but replication is needed. This opens up new perspective on the study of MS
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