A comparison of extrinsic clustering evaluation metrics based on formal constraints     

Enrique Amigό  Julio Gonzalo  Javier Artiles  Felisa Verdejo 《Information Retrieval》2009,12(5):613-613

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Utility of icteric index in clinical laboratories: more than a preanalytical indicator     

Rufino Mondejar  María Mayor Reyes  Enrique Melguizo Madrid  Consuelo Caavate Solano  Santiago Prez Ramos 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2021,31(2)

IntroductionTotal bilirubin tests are highly demanded in clinical laboratories. Since icteric index (I-index) has zero cost, we aimed to evaluate its clinical utility and cost-effectiveness to determine if total bilirubin is necessary to be tested. We took into account if haemolysis could interfere to icteric index determination.Material and methodsRetrospectively we reviewed I-index results in two cohorts (43,372 and 8507 non-haemolysed and haemolysed samples, respectively). All determinations were done using Alinity c chemistry analysers (Abbott Diagnostics). Receiver operating characteristic (ROC) curve was used to determine the optimal index cut-off to discriminate between normal and abnormal bilirubin concentration (20.5 µmol/L).ResultsThe ROC curve analysis suggested 21.4 µmol/L as the optimal I-index cut-off but differences in sensitivity and specificity were detected between patient derivation. For rejecting purpose, 15.4 µmol/L and 17.1 µmol/L I-index thresholds were selected based on patient derivation (inpatients and emergency room; and primary care and outpatients, respectively) with 97% sensitivity and 0.25% false negative results. Sensitivity was much lower in haemolysed samples. We selected 34.2 µmol/L I-index as threshold to detect hyperbilirubinemia with 99.7% specificity and 0.26% false positive results, independent of haemolysis. With the icteric index cut-offs proposed, we would save 66% of total bilirubin requested and analyse total bilirubin in around 2% of samples without total bilirubin requested.ConclusionsThis study supports the use of I-index to avoid bilirubin determination and to identify patients with hyperbilirubinemia. This work considers that the economic and test savings could help to increase the efficiency in clinical laboratories.  相似文献   

Decision support system through automatic algorithms and electronic request in diagnosis of anaemia for primary care patients     

Enrique Rodriguez-Borja  Adela Pozo-Giraldez  Macarena Díaz-Gimenez  Ausias Hervas-Romero  Africa Corchon-Peyrallo  Inmaculada Vinyals-Bellido  Arturo Carratala Calvo 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2021,31(2)

IntroductionAn appropriate management of anaemia laboratory tests is crucial for a correct diagnosis and treatment. A non-sequential “shotgun” approach (where every anaemia related test is ordered) causes workload and cost increases and could be potentially harmful. We have implemented a Decision Support System through our laboratory information system (LIMS) based on reflexive algorithms and automatic generation of interpretative reports specifically in diagnosis of anaemia for primary care patients.Materials and methodsWhen a request contained an “Anaemia Suspicion Study” profile, more than twenty automatic reflexive rules were activated in our LIMS based upon laboratory results. These rules normally involved the addition of reflexive tests. A final report was automatically generated for each interpretation which was always reviewed for their validity by two staff pathologists. We measured the impact of this system in the ordering of most common anaemia related tests and if a proper treatment was established based on the interpretive report.ResultsFrom all the studies performed, only 12% were positive being “iron deficiency” and “anaemia of chronic disease” the most frequent causes, 62% and 17%, respectively. Proper treatment was established in 88% of these anaemic patients. Total iron, transferrin, ferritin, folate and vitamin B12 demand decreased substantially after implementation representing a cost reduction of 40% only for these five tests.ConclusionsOur system has easily improved patient outcomes, advising on individual clinical cases. We have also noticeably reduced the number of over-requested tests and laboratory costs.  相似文献   

Pedometer ownership, motivation, and walking: do people walk the talk?     

Berry TR  Fraser SN  Spence JC  Garcia Bengoechea E 《Research quarterly for exercise and sport》2007,78(4):369-374

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Comparison of starts and turns of national and regional level swimmers by individualized-distance measurements     

Santiago Veiga  Antonio Cala  Pablo G. Frutos  Enrique Navarro 《Sports biomechanics / International Society of Biomechanics in Sports》2014,13(3):285-295

The aim of this study was to compare the race characteristics of the start and turn segments of national and regional level swimmers. In the study, 100 and 200-m events were analysed during the finals session of the Open Comunidad de Madrid (Spain) tournament. The “individualized-distance” method with two-dimensional direct linear transformation algorithm was used to perform race analyses. National level swimmers obtained faster velocities in all race segments and stroke comparisons, although significant inter-level differences in start velocity were only obtained in half (8 out of 16) of the analysed events. Higher level swimmers also travelled for longer start and turn distances but only in the race segments where the gain of speed was high. This was observed in the turn segments, in the backstroke and butterfly strokes and during the 200-m breaststroke event, but not in any of the freestyle events. Time improvements due to the appropriate extension of the underwater subsections appeared to be critical for the end race result and should be carefully evaluated by the “individualized-distance” method.  相似文献   

Role of vitamin B12 on methylmalonyl-CoA mutase activity     

Tóshiko Takahashi-I?iguez  Enrique García-Hernandez  Roberto Arreguín-Espinosa  María Elena Flores 《Journal of Zhejiang University. Science. B》2012,13(6):423-437

Vitamin B₁₂ is an organometallic compound with important metabolic derivatives that act as cofactors of certain enzymes, which have been grouped into three subfamilies depending on their cofactors. Among them, methylmalonyl-CoA mutase (MCM) has been extensively studied. This enzyme catalyzes the reversible isomerization of L-methylmalonyl-CoA to succinyl-CoA using adenosylcobalamin (AdoCbl) as a cofactor participating in the generation of radicals that allow isomerization of the substrate. The crystal structure of MCM determined in Propionibacterium freudenreichii var. shermanii has helped to elucidate the role of this cofactor AdoCbl in the reaction to specify the mechanism by which radicals are generated from the coenzyme and to clarify the interactions between the enzyme, coenzyme, and substrate. The existence of human methylmalonic acidemia (MMA) due to the presence of mutations in MCM shows the importance of its role in metabolism. The recent crystallization of the human MCM has shown that despite being similar to the bacterial protein, there are significant differences in the structural organization of the two proteins. Recent studies have identified the involvement of an accessory protein called MMAA, which interacts with MCM to prevent MCM’s inactivation or acts as a chaperone to promote regeneration of inactivated enzyme. The interdisciplinary studies using this protein as a model in different organisms have helped to elucidate the mechanism of action of this isomerase, the impact of mutations at a functional level and their repercussion in the development and progression of MMA in humans. It is still necessary to study the mechanisms involved in more detail using new methods.  相似文献   

Evolution in the Caribbean Classroom: A critical analysis of the role of biology teachers and science standards in shaping evolution instruction in Belize     

Elvis Enrique Nunez  Rose M. Pringle  Kevin Tyler Showalter 《International Journal of Science Education》2013,35(15):2421-2453

A survey of the literature on evolution instruction provides evidence that teachers’ personal views and understandings can shape instructional approaches and content delivered in science classrooms regardless of established science standards. This study is the first to quantify evolutionary worldviews of in-service teachers in the Caribbean, specifically in Belize, an English-speaking nation with a high school system guided by a regional biology syllabus and strict standardized tests. Using the Measure of Acceptance of the Theory of Evolution (MATE) instrument and knowledge test, we investigated (1) the current level of acceptance and understanding of evolution as given by 97% of high school biology teachers in Belize; (2) the factors associated with acceptance and understanding of evolutionary theory. With an average MATE score of 64.4 and a mean knowledge score of 47.9%, Belizean teachers were classified as having both ‘Low Acceptance’ and ‘Low Understanding’ of evolutionary theory. A positive correlation was found between teacher acceptance and understanding of evolution. A review of the Caribbean Secondary Examination Certificate biology syllabus suggests that evolution plays a minimal role in the high school biology classroom. We believe that Belize presents a unique opening for future training on evolution instruction since 57% of the biology teachers self-proclaim to be unprepared to teach evolution. The results of this study have implications for policy, practice and research with teachers’ acceptance, understanding and confidence in teaching evolution serving as important predictors for instructional approaches used in the biology classroom.  相似文献   

Early School-leaving in Spain: evolution,intensity and determinants     

Enrique Fernández-Macías  José-Ignacio Antón  Francisco-Javier Braña  Rafael Muñoz De Bustillo 《European Journal of Education》2013,48(1):150-164

Spain has one of the highest levels of early school leaving and educational failure of the European Union. The purpose of this paper is to analyse the anatomy of early school leaving in Spain and its characteristics. In order to do so, in the first part we discuss the measurement problems related with this concept and the evolution of drop-out rates in Spain. We argue that the published figures of early school leaving slightly underestimate the phenomenon, and discuss the impact of the increase in immigration rates on the level of educational failure and its very unequal distribution in terms of gender. In a second part, using data from the Labour Force Surveys of 2000 and 2007, we explore the factors behind educational failure by means of a logistic regression. The results of this model confirm the explanatory power of social reproduction hypotheses, but also show that there are important aspects of the patterns and recent evolution of early school leaving which cannot be explained by a single theoretical approach.  相似文献   

Ageism at university: A comparative analysis of young and older adult students     

Enrique Arias Fernández  Juan Lirio Castro  Inmaculada Herranz Aguayo  David Alonso González  Esther Portal Martínez 《Educational gerontology》2013,39(11):679-692

ABSTRACT

This study undertakes a comparative analysis of the negative stereotypes of older persons described by young and older adult university students at the University of Castilla-La Mancha. This study is innovative in that it compares three analytical perspectives: the perception of young students (18–27 years); the perception of older adult students (50 years and above) regarding older persons (hetero-stereotypes); and, finally, the perception of older adult students with regard to themselves as part of the group of older adult students (self-stereotypes).

The sample is made up of 460 young students and 148 older adult students who completed the Questionnaire on Negative Ageing Stereotypes (QNAS), comprising three dimensions: health; character and personality; and social relationships and motivation. A statistical analysis was subsequently carried out using the independent samples t-test in the IBM Statistics 19.0 program.

Of note among the principal results is the low level of negative stereotypes reported among the groups studied, as well as the existence of significant differences in their means, which indicate that the negative stereotypes of the groups differed. The most stereotyped of the dimensions analyzed was character and personality. In contrast, the least-stereotyped dimension was that of social relationships and motivation. Finally, the dimension of health occupied an intermediate position. With regard to the three perspectives studied, the older adult group (hetero-stereotypes) was the most stereotyped, followed by the young students and, finally, the older adult students with reference to self-stereotypes.  相似文献   

Author-level metrics in the new academic profile platforms: The online behaviour of the Bibliometrics community     

Alberto Martín-Martín  Enrique Orduna-Malea  Emilio Delgado López-Cózar 《Journal of Informetrics》2018,12(2):494-509

The new web-based academic communication platforms do not only enable researchers to better advertise their academic outputs, making them more visible than ever before, but they also provide a wide supply of metrics to help authors better understand the impact their work is making. This study has three objectives: a) to analyse the uptake of some of the most popular platforms (Google Scholar Citations, ResearcherID, ResearchGate, Mendeley and Twitter) by a specific scientific community (bibliometrics, scientometrics, informetrics, webometrics, and altmetrics); b) to compare the metrics available from each platform; and c) to determine the meaning of all these new metrics. To do this, the data available in these platforms about a sample of 811 authors (researchers in bibliometrics for whom a public profile Google Scholar Citations was found) were extracted. A total of 31 metrics were analysed. The results show that a high number of the analysed researchers only had a profile in Google Scholar Citations (159), or only in Google Scholar Citations and ResearchGate (142). Lastly, we find two kinds of metrics of online impact. First, metrics related to connectivity (followers), and second, all metrics associated to academic impact. This second group can further be divided into usage metrics (reads, views), and citation metrics. The results suggest that Google Scholar Citations is the source that provides more comprehensive citation-related data, whereas Twitter stands out in connectivity-related metrics.  相似文献