1,255 research outputs found

    Validation of in situ applicable measuring techniques for analysis of the water adsorption by stone

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    As the water adsorbing behaviour (WAB) of stone is a key factor for most degradation processes, its analysis is a decisive aspect when monitoring deterioration and past conservation treatments, or when selecting a proper conservation treatment. In this study the performance of various non-destructive methods for measuring the WAB are compared, with the focus on the effect of the variable factors of the methods caused by their specific design. The methods under study are the contact-sponge method (CSM), the Karsten tube (KT) and the Mirowski pipe (MIR). Their performance is compared with the standardized capillary rise method (CR) and the results are analysed in relation to the open porosity of different lithotypes. Furthermore the effect of practical encumbrances which could limit the application of these methods was valuated. It was found that KT and CSM have complementary fields of investigation, where CSM is capable of measuring the initial water uptake of less porous materials with a high precision, while KT was found commodious for measuring longer contact times for more porous lithotypes. MIR showed too many discommodities, leading to unreliable results. To adequately compare the results of the different methods, the size of the contact area appears to be the most influential factor, whereas the contact material and pressure on the surface do not indicate a significant influence on the results. The study of these factors is currently being extended by visualization of the water adsorption process via X-ray and neutron radiography in combination with physico-mathematical models describing the WAB

    Impact of gout on the risk of atrial fibrillation

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    OBJECTIVES: To examine the risk of atrial fibrillation (AF) at the time of first diagnosis of gout compared with matched controls and to follow incident gout patients and their matched controls after diagnosis to compare their subsequent risk of AF. METHODS: From the UK Clinical Practice Research Data-link, 45 378 incident gout patients and 45 378 age-, sex-, practice-, registration year- and index year-matched controls were identified. Index dates were initial diagnosis date for gout patients and their matched controls. The risk of AF at diagnosis [odds ratios (ORs), using conditional logistic regression] and after the diagnosis of gout [hazard ratios (HRs), using Cox proportional models] were estimated, adjusted for BMI, smoking, alcohol consumption, ischaemic heart disease, heart failure, heart valve disease, hyperthyroidism and other comorbidities and medications. RESULTS: The prevalence of AF at index date in gout patients (male, 72.3%; mean age, 62.4 +/- 15.1 years) was 7.42% (95% CI 7.18, 7.66%) and in matched controls 2.83% (95% CI 2.67, 2.98%). The adjusted OR (95% CI) was 1.45 (1.29, 1.62). The cumulative probability of AF at 1, 2, 5 and 10 years after index date was 1.08, 2.03, 4.77 and 9.68% in gout patients and 0.43, 1.08, 2.95 and 6.33% in controls, respectively (log-rank test, P < 0.001). The adjusted HR (95% CIs) was 1.09 (1.03, 1.16). CONCLUSION: This population-based study indicates that gout is independently associated with a higher risk of AF at diagnosis and the risk is also higher after the diagnosis

    Comparison of non-destructive techniques for analysis of the water absorbing behavior of stone

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    Existing non-destructive techniques for analysis of the water absorbing behavior of stone material have a different nature. This leads to discrepancies in practical application and measuring area, resulting in difficulties when comparing results of different methods. The present study focuses on the comparison of different non-destructive methods in terms of practical application, influence of variable factors and accuracy in relation to the open porosity and the capillary rise measurements. The comparison was based on repetitive measurements and X-ray and neutron radiography of the water absorption by lithotypes with a varying open porosity. The methods under study are the Karsten tube (KT), the contact sponge method (CSM) and the Mirowski pipe (MIR). It can be concluded that KT and CSM have complementary fields of investigation, whereas MIR produces unreliable results due to practical discommodities. The most significant variable factor influencing the measurements is the surface of the contact area. A study of analytical models describing the capillary water absorption as reference for interpretation of results of the different methods is currently ongoing

    THE EFFECT OF SCHOOL HEADS' LEADERSHIP STYLE ON LEARNERS' PERCEPTION OF SCHOOL CLIMATE

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    A positive school climate and excellent leadership are essential to promote holistic school administration and high-quality education. Research­ers wanted to find out how school leaders' leadership styles affect the percepti­on of students in a high-quality educational environment using a mixed-method research design. A total of 1018 people participated in this survey, including 907 students and 111 school officials from 24 different schools. The Multifac­tor Leadership Questionnaire (MLQ) was used to determine the most common le­adership style among school heads. The SCAI Secondary General Version was used to assess students' perceptions of the school climate level. Also, four school principals participated in one-on-one interviews on how their leader­ship styles changed during the pandemic. All aspects of school climate, in­clud­ing community relations, student interactions, learning and assessment, physi­cal appearance, discipline environment, attitude, and culture, had high levels of perceived school climate. Results show that transformational leadership, con­tingent reward, management by exception, and inspirational motivation are the most prevalent styles of leadership, while laissez-faire, idealized influence, and intellectual stimulation are the least prevalent. Only two out of forty-two (42) correlations between school atmosphere and leadership style were significant. Student interactions and idealized influence are also included in this cate­gory. School administrators and teachers need to understand the level of trans­formational leadership and the school climate to create the best school environ­ment, which will improve the quality of teaching and learning and, in the end, school performance

    Intra and inter-session reliability of rapid Transcranial Magnetic Stimulation stimulus-response curves of tibialis anterior muscle in healthy older adults

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    Objective: The clinical use of Transcranial Magnetic Stimulation (TMS) as a technique to assess corticospinal excitability is limited by the time for data acquisition and the measurement variability. This study aimed at evaluating the reliability of Stimulus-Response (SR) curves acquired with a recently proposed rapid protocol on tibialis anterior muscle of healthy older adults. Methods: Twenty-four neurologically-intact adults (age:55–75 years) were recruited for this test-retest study. During each session, six SR curves, 3 at rest and 3 during isometric muscle contractions at 5% of maximum voluntary contraction (MVC), were acquired. Motor Evoked Potentials (MEPs) were normalized to the maximum peripherally evoked response; the coil position and orientation were monitored with an optical tracking system. Intra- and inter-session reliability of motor threshold (MT), area under the curve (AURC), MEPmax, stimulation intensity at which the MEP is mid-way between MEPmax and MEPmin (I50), slope in I50, MEP latency, and silent period (SP) were assessed in terms of Standard Error of Measurement (SEM), relative SEM, Minimum Detectable Change (MDC), and Intraclass Correlation Coefficient (ICC). Results: The relative SEM was ≤10% for MT, I50, latency and SP both at rest and 5%MVC, while it ranged between 11% and 37% for AURC, MEPmax, and slope. MDC values were overall quite large; e.g., MT required a change of 12%MSO at rest and 10%MSO at 5%MVC to be considered a real change. Inter-sessions ICC were >0.6 for all measures but slope at rest and MEPmax and latency at 5%MVC. Conclusions: Measures derived from SR curves acquired in <4 minutes are affected by similar measurement errors to those found with long-lasting protocols, suggesting that the rapid method is at least as reliable as the traditional methods. As specifically designed to include older adults, this study provides normative data for future studies involving older neurological patients (e.g. stroke survivors)

    TRAF6 Phosphorylation Prevents Its Autophagic Degradation and Re-Shapes LPS-Triggered Signaling Networks

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    The ubiquitin E3 ligase TNF Receptor Associated Factor 6 (TRAF6) participates in a large number of different biological processes including innate immunity, differentiation and cell survival, raising the need to specify and shape the signaling output. Here, we identify a lipopolysaccharide (LPS)-dependent increase in TRAF6 association with the kinase IKKε (inhibitor of NF-κB kinase subunit ε) and IKKε-mediated TRAF6 phosphorylation at five residues. The reconstitution of TRAF6-deficient cells, with TRAF6 mutants representing phosphorylation-defective or phospho-mimetic TRAF6 variants, showed that the phospho-mimetic TRAF6 variant was largely protected from basal ubiquitin/proteasome-mediated degradation, and also from autophagy-mediated decay in autolysosomes induced by metabolic perturbation. In addition, phosphorylation of TRAF6 and its E3 ligase function differentially shape basal and LPS-triggered signaling networks, as revealed by phosphoproteome analysis. Changes in LPS-triggered phosphorylation networks of cells that had experienced autophagy are partially dependent on TRAF6 and its phosphorylation status, suggesting an involvement of this E3 ligase in the interplay between metabolic and inflammatory circuits

    Enfoques de la resiliencia ante el cambio climático.

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    Climate change affects directly the food system, reducing food availability and increasing access inequality for unfavorable sectors of the population. Resilience is the ability of the system to absorb disturbances or the promptness to recover from climate disturbances, and when applying the term, social resilience is created as the ability of communities to maintain the social structure in face of external shocks. The objective is to analyze different approaches of this concept in twelve publications that review cases in relation to extreme events caused by climate change and what is the role of peasant and indigenous organizations in them. As a result it was found that half of the studies search in terms of organizations, their analysis, horizontal dialogue, that they are actors and authors, while the rest attempt to instruct and follow scientificism and a vertical discourse of possession of knowledge. In conclusion, it mentions that it is a stage of making visible the postures that come from indigenous and peasant organizations as subjects. The importance of this historical moment is the possibility of taking real actions of climate change mitigation by these subjects that are heard and as a whole take over spaces that were previously denied.El cambio climático afecta directamente al sistema alimentario, reduciendo la disponibilidad de alimentos e incrementando la desigualdad del acceso a sectores desfavorecidos de la población. La resiliencia es la habilidad del sistema para absorber perturbaciones o la rapidez para recobrarse de disturbios climáticos y en una aplicación del término se crea la resiliencia social como la habilidad de las comunidades para mantener la estructura social ante shocks externos. El objetivo es analizar diferentes enfoques de este concepto en doce publicaciones que revisan casos en relación con eventos extremos causados por el cambio climático y cuál es el papel de las organizaciones campesinas e indígenas en estas. Como resultado se encontró que la mitad de trabajos buscan en cuanto a las organizaciones, su análisis, el diálogo horizontal, que sean actores y que sean los autores, mientras los restantes pretenden instruir y siguen el discurso cientificista y vertical de posesión del conocimiento. En conclusión, menciona que se está en una etapa de visibilización de las posturas que provienen de organizaciones indígenas y campesinas como sujetos. La importancia de este momento histórico es la posibilidad de tomar acciones reales de mitigación del cambio climático por estos sujetos que se escuchan y en conjunto toman espacios antes negados

    The Climate-system Historical Forecast Project: providing open access to seasonal forecast ensembles from centers around the globe

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    Fil: Tompkins, Adrian M.. The Abdus Salam; ItaliaFil: Ortiz de Zarate, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones del Mar y la Atmósfera. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones del Mar y la Atmósfera; Argentina. Centre National de la Recherche Scientifique; FranciaFil: Saurral, Ramiro Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones del Mar y la Atmósfera. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones del Mar y la Atmósfera; Argentina. Centre National de la Recherche Scientifique; FranciaFil: Vera, Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones del Mar y la Atmósfera. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones del Mar y la Atmósfera; Argentina. Centre National de la Recherche Scientifique; FranciaFil: Saulo, Andrea Celeste. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Ministerio de Defensa. Secretaria de Planeamiento. Servicio Meteorológico Nacional; ArgentinaFil: Merryfield, William J.. Canadian Centre for Climate Modelling and Analysis; CanadáFil: Sigmond, Michael. Canadian Centre for Climate Modelling and Analysis; CanadáFil: Lee, Woo Sung. Canadian Centre for Climate Modelling and Analysis; CanadáFil: Baehr, Johanna. Universitat Hamburg; AlemaniaFil: Braun, Alain. Météo-France; FranciaFil: Amy Butler. National Ocean And Atmospheric Administration; Estados UnidosFil: Déqué, Michel. Météo-France; FranciaFil: Doblas Reyes, Francisco J.. Institució Catalana de Recerca i Estudis Avancats; España. Barcelona Supercomputing Center - Centro Nacional de Supercomputacion; EspañaFil: Gordon, Margaret. Met Office; Reino UnidoFil: Scaife, Adam A.. University of Exeter; Reino UnidoFil: Yukiko Imada. Japan Meteorological Agency. Meteorological Research Institute. Climate Research Department; JapónFil: Masayoshi Ishii. Japan Meteorological Agency. Meteorological Research Institute. Climate Research Department; JapónFil: Tomoaki Ose. Japan Meteorological Agency. Meteorological Research Institute. Climate Research Department; JapónFil: Kirtman, Ben. University of Miami; Estados UnidosFil: Kumar, Arun. National Ocean And Atmospheric Administration; Estados UnidosFil: Müller, Wolfgang A.. Max-Planck-Institut für Meteorologie; AlemaniaFil: Pirani, Anna. Université Paris-Saclay; FranciaFil: Stockdale, Tim. European Centre for Medium-Range Weather; Reino UnidoFil: Rixen, Michel. World Meteorological Organization. World Climate Research Programme; SuizaFil: Yasuda, Tamaki. Japan Meteorological Agency. Climate Prediction Division; Japó

    The Naked Mole Rat Genome Resource: facilitating analyses of cancer and longevity-related adaptations

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    Motivation: The naked mole rat (Heterocephalus glaber) is an exceptionally long-lived and cancer-resistant rodent native to East Africa. Although its genome was previously sequenced, here we report a new assembly sequenced by us with substantially higher N50 values for scaffolds and contigs. Results: We analyzed the annotation of this new improved assembly and identified candidate genomic adaptations which may have contributed to the evolution of the naked mole rat’s extraordinary traits, including in regions of p53, and the hyaluronan receptors CD44 and HMMR (RHAMM). Furthermore, we developed a freely available web portal, the Naked Mole Rat Genome Resource (http://www.naked-mole-rat.org), featuring the data and results of our analysis, to assist researchers interested in the genome and genes of the naked mole rat, and also to facilitate further studies on this fascinating species. Availability and implementation: The Naked Mole Rat Genome Resource is freely available online at http://www.naked-mole-rat.org. This resource is open source and the source code is available at https://github.com/maglab/naked-mole-rat-portal. Contact: [email protected]

    Assessment of potential cardiotoxic side effects of mitoxantrone in patients with multiple sclerosis

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    Previous studies showed that mitoxantrone can reduce disability progression in patients with multiple sclerosis (MS). There is, however, concern that it may cause irreversible cardiomyopathy with reduced left ventricular (LV) ejection fraction (EF) and congestive heart failure. The aim of this prospective study was to investigate cardiac side effects of mitoxantrone by repetitive cardiac monitoring in MS patients. The treatment protocol called for ten courses of a combined mitoxantrone (10 mg/m(2) body surface) and methylprednisolone therapy. Before each course, a transthoracic echocardiogram was performed to determine the LV end-diastolic diameter, the end-systolic diameter and the fractional shortening; the LV-EF was calculated. Seventy-three patients participated (32 males; age 48 +/- 12 years, range 20-75 years; 25 with primary progressive, 47 with secondary progressive and 1 with relapsing-remitting MS) who received at least four courses of mitoxantrone. Three of the 73 patients were excluded during the study (2 patients discontinued therapy; 1 patient with a previous history of ischemic heart disease developed atrial fibrillation after the second course of mitoxantrone). The mean cumulative dose of mitoxantrone was 114.0 +/- 33.8 mg. The mean follow-up time was 23.4 months (range 10-57 months). So far, there has been no significant change in any of the determined parameters (end-diastolic diameter, end-systolic diameter, fractional shortening, EF) over time during all follow-up investigations. Mitoxantrone did not cause signs of congestive heart failure in any of the patients. Further cardiac monitoring is, however, needed to determine the safety of mitoxantrone after longer follow-up times and at higher cumulative doses. Copyright (C) 2005 S. Karger AG, Basel
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