1,720,964 research outputs found
Partial Least Squares Regression: A Valuable Method for Modeling Molecular Behavior in Hemodialysis
No full textThe aim of this work was to use the Partial Least Squares Regression (PLS) technique to fit simple models for the interpretation of an underlying complex process. In this study, the technique was used to build a statistical model for molecular kinetic data obtained from hemodialyzed patients. By using PLS we derived statistical linear models for the prediction of the equilibrated urea concentration. Models with an average relative prediction error (RPE) of less than 0.05% were achieved. The model predictive accuracy was evaluated in a cross-center study yielding an RPE < 3%. The chosen model was robust to variations such as sampling extraction time demonstrating a high capacity for modeling kinetics. It also was found to be useful for bed-side monitoring. Finally, the PLS technique allowed identification of the most important co-variables in the model and of those patients with outlier patterns in their molecular dynamics.Fil: Fernandez, Elmer Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Católica de Córdoba; ArgentinaFil: Valtuille, Rodolfo. No especifíca;Fil: Willshaw, Peter. Swansea University; Reino UnidoFil: Balzarini, Monica Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Córdoba; Argentin
Nutritional markers and body composition in hemodialysis patients
Full text linkThe aims of this study were to analyse body composition, to detect the presence of undernutrition, and to establish a relationship between undernutrition and the biological markers routinely used as indicators of nutritional status in hemodialysis (HD) patients (pts). We used a body composition monitor (BCM) that expresses body weight in terms of lean tissue mass (LTM) and fat tissue mass (FTM) independent of hydration status. From nine HD units, 934 pts were included. Undernutrition was defined as having a lean tissue index (LTI = LTM/height2) below the 10th percentile of a reference population. Biochemical markers and parameters delivered by BCM were used to compare low LTI and normal LTI groups. Undernutrition prevalence was 58.8% of the population studied. Low LTI pts were older, were significantly more frequently overhydrated, and had been on HD for a longer period of time than the normal LTI group. FTI (FTI = FTM/ height2) was significantly higher in low LTI pts and increased according to BMI. LTI was not influenced by different BMI levels. Albumin and C-reactive protein correlated inversely (). However neither of them was statistically different when considering undernourished and normal LTI pts. Our BCM study was able to show a high prevalence of undernutrition, as expressed by low LTI. In our study, BMI and other common markers, such as albumin, failed to predict malnutrition as determined by BCM.Fil: Valtuille, Rodolfo. Fresenius Medical Care; ArgentinaFil: Casos, Maria Elisa. Fresenius Medical Care; ArgentinaFil: Fernandez, Elmer Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigación y Desarrollo en Inmunología y Enfermedades Infecciosas. Universidad Católica de Córdoba. Centro de Investigación y Desarrollo en Inmunología y Enfermedades Infecciosas; ArgentinaFil: Guinsburg, Adrian. FME Burzaco; ArgentinaFil: Marelli, Cristian. FME Burzaco; Argentin
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Estimated glomerular filtration rate as a predictor of cardiovascular risk
No full textContexto: la enfermedad renal crónica (ERC) representa un desafío global de salud, con una creciente prevalencia impulsada por factores como hipertensión, diabetes y obesidad. Su relación con la enfermedad cardiovascular (ECV) es estrecha, ya que la disminución del filtrado glomerular (FG) aumenta el riesgo de eventos cardiovasculares. En este marco, la estimación del FG se ha convertido en una herramienta clave para evaluar la progresión de la ERC y su impacto en la ECV.
Objetivo: el estudio analiza el FG estimado (FGe) como predictor de riesgo cardiovascular en pacientes con ERC, explorando diversas fórmulas de estimación, su precisión y sus implicaciones clínicas. También examina situaciones especiales como la hiperfiltración glomerular (HFG) y el síndrome de hipo-filtración selectiva (SHS), recientemente descritas y relacionadas con la ECV.
Metodología: se realizó una revisión de la literatura en bases de datos científicas como PubMed, Ovid-MEDLINE, Web of Science y EMBASE, abarcando estudios publicados entre enero de 2000 y abril de 2024. Se analizaron fórmulas de estimación del FG basadas en creatinina (Cr) y cistatina C (Cis C), considerando su aplicabilidad clínica y limitaciones.
Resultados: se destaca que el FGe basado en Cr es ampliamente utilizado por su accesibilidad, pero tiene limitaciones en precisión. La inclusión de Cis C mejora la predicción de riesgo cardiovascular y progresión de la ERC. Además, valores elevados de FG pueden indicar sobreestimación y riesgo cardiovascular. El SHS, asociado con inflamación y ECV, subraya la necesidad de una evaluación más precisa del FG.
Conclusiones: el diagnóstico temprano de la ERC es clave para reducir su progresión y el impacto en la ECV. Las fórmulas de FGe han mejorado su precisión, pero aún presentan variabilidad significativa. La integración de Cis C y el reconocimiento de nuevas entidades como el SHS y la HFG pueden optimizar la predicción del riesgo cardiovascular en pacientes con ERC.Context: Chronic kidney disease (CKD) represents a global public health challenge, with increasing prevalence driven by factors such as hypertension, diabetes, and obesity. Its strong association with cardiovascular disease (CVD) highlights the critical role of estimated glomerular filtration rate (eGFR) in assessing CKD progression and cardiovascular risk. Given its significance, refining eGFR estimations is essential for improving risk prediction and clinical management.
Objective: This study evaluates eGFR as a predictor of cardiovascular risk in CKD patients, assessing the accuracy of various estimation formulas and their clinical implications. Additionally, it explores emerging renal filtration abnormalities, such as glomerular hyperfiltration (GHF) and selective hypofiltration syndrome (SHS), which have gained attention for cardiovascular associations.
Methodology: A systematic literature review was conducted across major scientific databases, including PubMed, Ovid-MEDLINE, Web of Science, EMBASE, and Redalyc. The search covered publications from January 2000 to April 2024, focusing on studies that examined eGFR estimations based on creatinine (Cr) and cystatin C (Cys C) and their predictive utility for cardiovascular outcomes.
Results: Creatinine-based eGFR is widely used due to its accessibility; however, its precision is limited. Incorporating Cys C improves risk stratification for both CKD progression and cardiovascular events. Elevated eGFR values may signal overestimation rather than optimal kidney function, thus influencing cardiovascular risk assessment. Furthermore, SHS, associated with inflammatory markers and CVD, underscores the need for refined filtration assessments beyond conventional metrics.
Conclusions: Early CKD diagnosis is crucial for mitigating disease progression and reducing cardiovascular morbidity. While eGFR estimation has improved, significant variability persists. Integrating Cys C into predictive models and recognizing newly characterized filtration syndromes such as SHS and GHF may enhance cardiovascular risk assessment in CKD patients
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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