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41.
IntroductionOesophageal varices are routinely diagnosed by esophagogastroduodenoscopy (EGD), and their bleeding has high mortality. We aimed to evaluate diagnostic performance of biochemical tests in comparison to elastography-based approaches, as non-invasive alternatives to EGD, for ruling-out high risk oesophageal varices (HRV).Material and methodsRetrospective analysis of patients (N = 861) who underwent liver stiffness measurement (LSM) by transient elastography (TE) in a single centre over 5-year period, with available results of EGD (within 3 months from LSM). Only patients with suspicion of compensated advanced chronic liver disease (cACLD) defined by LSM ≥ 10 kPa were included comprising the final cohort of 73 subjects. Original and expanded Baveno VI criteria (B6C), controlled attenuation parameter (CAP), platelet count (PLT), aspartate aminotransferase to PLT ratio index (APRI), Fibrosis-4 index (FIB4), model for end stage liver disease (MELD) score were evaluated against the results of EGD that served as the reference method.ResultsAnalysed patients had median age 62 years, 59/73 (0.81) were males, 54/73 (0.74) had alcoholic/non-alcoholic fatty liver disease, and 21/73 (0.29) had HRV. In multivariate logistic regression analysis only LSM and PLT were independently associated with HRV. The best performing tests for ruling-out HRV (% of spared EGD; % of missed HRV) were respectively: LSM < 20 kPa (53.4%; 0%), B6C (38%; 0%), Expanded B6C (47.9%; 4.8%); PLT > 214x109/L (21.9%; 0%); FIB4 ≤ 1.8 (21.4%; 0%), APRI ≤ 0.34 (12.3%; 0%). CAP, MELD = 6 alone or combined with PLT > 150(x109/L) did not show acceptable performance.ConclusionThe best performing biochemical tests for ruling-out HRV in our cohort of patients were PLT and FIB-4, but they were still outperformed by elastography-based approaches.Keyword: portal hypertension, cirrhosis, platelet count, esophageal varices, non-invasive tests  相似文献   
42.
Ecommerce is developing into a fast-growing channel for new business, so a strong presence in this domain could prove essential to the success of numerous commercial organizations. However, there is little research examining ecommerce at the individual customer level, particularly on the success of everyday ecommerce searches. This is critical for the continued success of online commerce. The purpose of this research is to evaluate the effectiveness of search engines in the retrieval of relevant ecommerce links. The study examines the effectiveness of five different types of search engines in response to ecommerce queries by comparing the engines’ quality of ecommerce links using topical relevancy ratings. This research employs 100 ecommerce queries, five major search engines, and more than 3540 Web links. The findings indicate that links retrieved using an ecommerce search engine are significantly better than those obtained from most other engines types but do not significantly differ from links obtained from a Web directory service. We discuss the implications for Web system design and ecommerce marketing campaigns.  相似文献   
43.
The economic status of families and their children's learning outcomes are closely related. For example, children living in poverty tend to score worse on measures of reading and math performance than their more affluent peers, and this achievement gap is present by kindergarten. In this study, we identified protective factors associated with school readiness among an Arizona sample of children living at or below the federal poverty line (N = 230). Using multiple linear regression, we examined the association between assessments of school readiness, health status, childcare hours, home language, parent engagement, and parent education. We found that increased weekly childcare hours and better health were associated with higher proficiency in math, literacy, and approaches to learning, and may serve as resilience factors for children in poverty that may contribute to closing the achievement gap.  相似文献   
44.
This paper analyses the role that different components of the academic strength of the secondary-school curriculum (i.e. number, subjects and grades of advanced academic courses) play in explaining social origin differences in access to prestigious universities (but also to other higher education institutions) in Scotland and the USA. A central aim of the paper is to investigate whether the mechanism behind the studied patterns of inequality differs depending on the characteristics of each educational system. Our results show pronounced social class gaps in entering top higher education institutions in both Scotland and the USA. Academic curriculum plays an important role in explaining these social class differences in both countries. However, while in Scotland type of subjects taken at an advanced level is the strongest mediator for the identified social class differences, in the USA, number of advanced subjects is the strongest. Moreover, taking into account the three academic components combined entirely explains the social class differences in Scotland. Considerable inequalities which are not explained by the strength of academic curriculum remain in the USA.  相似文献   
45.
Over the last decades, various policies at national and local levels have been implemented to widen participation in higher education (HE) in Scotland and more widely in the UK. Despite this, the acquisition of a HE qualification is still largely determined by the family in which individuals are born. Our study provides new evidence on the extent to which family factors matter by examining sibling data from the Scottish Longitudinal Study, a large-scale linkage study created using data from administrative and statistical sources. Random effects linear probability models are used to analyse individual and family-level variance in the chances of obtaining a HE qualification. Our results show that about 40% of the variation in the chances of attaining a university degree is explained by siblings’ shared family characteristics and about a third of this share is explained by parental social class, education and housing tenure. A high degree of sibling similarity in the outcome was found across all social-origin classes. However, while siblings of advantaged families are alike because they both graduated from HE, siblings of disadvantaged families are alike because neither of them did. We suggest that parental compensatory strategies in the former families and economic constraints in the latter families may explain such stark patterns of inequality. Finally, we do not find evidence that the availability of sub-degrees makes a difference to these patterns.  相似文献   
46.
Educational Studies in Mathematics - This paper describes the difficulties faced by a group of middle school students (13- to 15-year-olds) attempting to translate algebraic statements written in...  相似文献   
47.
This study seeks to understand the factors that contribute to a type of student–faculty interaction known to have particular benefits for students, faculty mentorship. Using three-time-point data from the Cooperative Institutional Research Program at the University of California, Los Angeles, this study employed structural equation modeling to investigate the relationship between contact and communication with faculty in the first year of college and faculty mentorship in the senior year. Results suggest that early interaction with faculty serves as a socialization process in college that leads students to have more meaningful interactions with faculty later in college, in the form of mentorship. The study extends the field’s understanding of faculty mentorship and offers important implications for institutional practices.  相似文献   
48.
There are practical difficulties in making intercultural education a substantial element of inclusion in both primary and compulsory secondary education in Europe. The Spanish education system and, in particular, the Catalan education system, have developed a series of strategies in response to the new multicultural complexity encountered in both the classroom and society as a whole. In this study, several inclusive attempts of the Catalan education system will be discussed. As a consequence of their analysis, educational models that are compatible with the framework of inclusive education will be presented as an effective means of promoting greater social integration and a peaceful coexistence in the school context.  相似文献   
49.
In this paper, we investigate the determinants of over-education in Japan and evaluate its opportunity costs for university graduates. To this end, we use the REFLEX data. Results reveal that over-education level in Japan is high and it brings an important wage penalty for Japanese workers. Large firm and high occupations point toward a significant reduction in the likelihood of over-education. Results for wage regressions for over-education indicate that Japanese workers who achieve jobs in large organizations will experience 20 % increase in their wage due to the firm size and, if over-educated, their increase in wage will remain positive. Results for women are puzzling as there is no significant effect associated with gender.  相似文献   
50.
ABSTRACT

The article argues that chronic unemployment has become the main context of youth policies in Spain and Brazil. Our point is that the current structural crisis of the capitalist system eventually provokes chronic unemployment. To be precise, both business and international organisations have endorsed structural adjustments and austerity policies that have destroyed productive forces through expropriation and exploitation in many countries, thus expanding chronic unemployment despite youth policies claiming otherwise. In Spain, two public policies try to circumvent the adverse situation of many youth, namely: the Quality of Education Act (LOMCE) and the Youth Guarantee Scheme. Brazil follows the same logic of these policies through initiatives such as the High School reform and Projovem program. However, in both countries the structural crisis threatens the future of young generations despite these fashionable policies exclusively targeted to them.  相似文献   
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