36 research outputs found

    Fracture Detection in Bio-Glues with Fluorescent-Protein-Based Optical Force Probes

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    Glues are being used to bond, seal, and repair in industry and biomedicine. The improvement of gluing performance is hence important for the development of new glues with better and balanced property spaces, which in turn necessitates a mechanistic understanding of their mechanical failure. Optical force probes (OFPs) allow the observation of mechanical material damage in polymers from the macro- down to the microscale, yet have never been employed in glues. Here, the development of a series of ratiometric OFPs based on fluorescent-protein–dye and protein–protein conjugates and their incorporation into genetically engineered bio-glues is reported. The OFPs are designed to efficiently modulate Förster resonance energy transfer upon force application thereby reporting on force-induced molecular alterations independent of concentration and fluorescence intensity both spectrally and through their fluorescence lifetime. By fluorescence spectroscopy in solution and in the solid state and by fluorescence lifetime imaging microscopy, stress concentrations are visualized and adhesive and cohesive failure in the fracture zone is differentiated.</p

    Strontium hexaferrite platelets: a comprehensive soft X-ray absorption and Mössbauer spectroscopy study

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    IBERMÖSS-2019, Bilbao, 30-31 may 2019. --https://www.ehu.eus/es/web/ibermossmeetingStrontium ferrite (SFO, SrFe12O19) is a ferrite employed for permanent magnets due to its high magnetocrystalline anisotropy. Since its discovery in the mid-20th century, this hexagonal ferrite has become an increasingly important material both commercially and technologically, finding a variety of uses and applications. Its structure can be considered a sequence of alternating spinel (S) and rocksalt (R) blocks. All the iron cations are in the Fe3+ oxidation state and it has a ferrimagnetic configuration with five different cationic environments for the iron (three octahedral sites, a tetraedrical site and a bipiramidal site)[1,2]. We have studied the properties of SrFe 12O19 in the shape of platelets, up to several micrometers in width, and tens of nanometers thick, synthesized by a hydrothermal method. We have characterized the structural and magnetic properties of these platelets by Mössbauer spectroscopy, x-ray transmission microscopy (TMX), transmission electron microscopy (TEM), x-ray diffraction (XRD), vibrating-sample magnetometry (VSM), x-ray absorption spectroscopy (XAS), x-ray circular magnetic dichroism (XMCD) and photoemission electron microscopy (PEEM). To the best of our knowledge this is the first time that the x-ray absorption spectra at the Fe L 2,3 edges of this material in its pure form have been reported. The Mössbauer results recorded from these platelets both in the electron detection and transmission modes have helped to understand the iron magnetic moments determined by XMCD (Fig.1). The experimental results have been complemented with multiplet calculations aimed at reproducing the observed XAS and XMCD spectra at the Fe L 2,3 absorption edge, and by density functional theory (DFT) calculations to reproduce the oxygen K- absorption edge. Finally the domain pattern measured in remanence is in good agreement with micromagnetic simulations [3]

    Occurrence and identification of risk areas of Ixodes ricinus-borne pathogens: a cost-effectiveness analysis in north-eastern Italy

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    <p>Abstract</p> <p>Background</p> <p><it>Ixodes ricinus</it>, a competent vector of several pathogens, is the tick species most frequently reported to bite humans in Europe. The majority of human cases of Lyme borreliosis (LB) and tick-borne encephalitis (TBE) occur in the north-eastern region of Italy. The aims of this study were to detect the occurrence of endemic and emergent pathogens in north-eastern Italy using adult tick screening, and to identify areas at risk of pathogen transmission. Based on our results, different strategies for tick collection and pathogen screening and their relative costs were evaluated and discussed.</p> <p>Methods</p> <p>From 2006 to 2008 adult ticks were collected in 31 sites and molecularly screened for the detection of pathogens previously reported in the same area (i.e., LB agents, TBE virus, <it>Anaplasma phagocytophilum, Rickettsia </it>spp., <it>Babesia </it>spp., "<it>Candidatus Neoehrlichia mikurensis</it>"). Based on the results of this survey, three sampling strategies were evaluated <it>a</it>-<it>posteriori</it>, and the impact of each strategy on the final results and the overall cost reductions were analyzed. The strategies were as follows: tick collection throughout the year and testing of female ticks only (strategy A); collection from April to June and testing of all adult ticks (strategy B); collection from April to June and testing of female ticks only (strategy C).</p> <p>Results</p> <p>Eleven pathogens were detected in 77 out of 193 ticks collected in 14 sites. The most common microorganisms detected were <it>Borrelia burgdorferi </it>sensu lato (17.6%), <it>Rickettsia helvetica </it>(13.1%), and "<it>Ca. N. mikurensis</it>" (10.5%). Within the <it>B. burgdorferi </it>complex, four genotypes (i.e., <it>B. valaisiana, B. garinii, B. afzelii</it>, and <it>B. burgdorferi </it>sensu stricto) were found. Less prevalent pathogens included <it>R. monacensis </it>(3.7%), TBE virus (2.1%), <it>A. phagocytophilum </it>(1.5%), <it>Bartonella </it>spp. (1%), and <it>Babesia </it>EU1 (0.5%). Co-infections by more than one pathogen were diagnosed in 22% of infected ticks. The prevalences of infection assessed using the three alternative strategies were in accordance with the initial results, with 13, 11, and 10 out of 14 sites showing occurrence of at least one pathogen, respectively. The strategies A, B, and C proposed herein would allow to reduce the original costs of sampling and laboratory analyses by one third, half, and two thirds, respectively. Strategy B was demonstrated to represent the most cost-effective choice, offering a substantial reduction of costs, as well as reliable results.</p> <p>Conclusions</p> <p>Monitoring of tick-borne diseases is expensive, particularly in areas where several zoonotic pathogens co-occur. Cost-effectiveness studies can support the choice of the best monitoring strategy, which should take into account the ecology of the area under investigation, as well as the available budget.</p

    Eficacia del gel vaginal de coriolus versicolor en mujeres con lesiones cervicales asociadas al virus del papiloma humano. El estudio Paloma

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    Objetivo: el objetivo del estudio fue determinar la eficacia de un gel vaginal con Coriolus versicolor, Papilocare®, en la reparación de las lesiones cervicales de bajo grado causada por el virus del papiloma humano (VPH). Material y métodos: estudio multicéntrico, abierto, aleatorizado y controlado que implicó 91 mujeres positivas en VPH con alteraciones de bajo grado en citología cervical y colposcopia concordante. Resultados: el porcentaje de mujeres con citología normal y colposcopia concordante después de tres y seis meses de tratamiento con el gel fue significativamente mayor (78,0% y 84,9%) que en el grupo control (54,8% y 64,5%), principalmente en pacientes con VPH de alto riesgo (79,5% y 87,8% frente a 52,0% y 56,0%). A los seis meses, el aclaramiento de VPH fue mayor en pacientes que recibieron tratamiento respecto a las que no lo recibieron (59,6% frente a 41,9%), especialmente en las de alto riesgo (62,5% frente a 40,0%). En comparación con basal, el estrés percibido por las pacientes se redujo en el grupo de tratamiento (de 21,1 a 19,0), mientras que se incrementó en el grupo control (de 17,7 a 20,7). Se describieron siete posibles/probables efectos adversos relacionados con el tratamiento; la mayoría de severidad leve o moderada. Conclusión: el tratamiento con el gel vaginal con Coriolus versicolor ha demostrado un mayor beneficio clínico que la conducta clínica habitual, espera vigilante, tanto en la muestra total como en el subgrupo de alto riesgo, respecto a su eficacia para el tratamiento de las lesiones cervicales de bajo grado y el aclaramiento de las cepas de VPH después de seis meses de tratamiento. El gel vaginal ha presentado además un perfil de seguridad y tolerabilidad alto y ha conferido adicionalmente una importante mejora de la reepitelización cervical, una reducción del estrés percibido y una alta adherencia terapéutica.2021-2

    Analyzing factors that influence the folk use and phytonomy of 18 medicinal plants in Navarra

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    BACKGROUND: This article analyzes whether the distribution or area of use of 18 medicinal plants is influenced by ecological and cultural factors which might account for their traditional use and/or phytonymy in Navarra. This discussion may be helpful for comparative studies, touching as it does on other ethnopharmacological issues: a) which cultural and ecological factors affect the selection of medicinal plants; b) substitutions of medicinal plants in popular medicine; c) the relation between local nomenclature and uses. To analyze these questions, this paper presents an example of a species used for digestive disorders (tea and camomile: Jasonia glutinosa, J. tuberosa, Sideritis hyssopifolia, Bidens aurea, Chamaemelum nobile, Santolina chamaecyparissus...), high blood pressure (Rhamnus alaternus, Olea europaea...) or skin diseases (Hylotelephium maximum, H. telephium, Anagallis arvensis, A. foemina). METHODS: Fieldwork began on January 2004 and continued until December 2006. During that time we interviewed 505 informants in 218 locations in Navarra. Information was collected using semi-structured ethnobotanical interviews, and we subsequently made maps using Arc-View 8.0 program to determine the area of use of each taxon. Each map was then compared with the bioclimatic and linguistic map of Navarra, using the soil and ethnographic data for the region, and with other ethnobotanical and ethnopharmacological studies carried out in Europe. RESULTS: The results clearly show that ecological and cultural factors influence the selection of medicinal plants in this region. Climate and substrate are the most important ecological factors that influence the distribution and abundance of plants, which are the biological factors that affect medicinal plant selection. CONCLUSION: The study of edaphological and climatological factors, on the one hand, and culture, on the other, can help us to understand why a plant is replaced by another one for the same purposes, either in the same or in a different area. In many cases, the cultural factor means that the use of a species is more widespread than its ecological distribution. This may also explain the presence of synonyms and polysemies which are useful for discussing ethnopharmacological data

    Understanding the relation between Zika virus infection during pregnancy and adverse fetal, infant and child outcomes: a protocol for a systematic review and individual participant data meta-analysis of longitudinal studies of pregnant women and their infants and children

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    IntroductionZika virus (ZIKV) infection during pregnancy is a known cause of microcephaly and other congenital and developmental anomalies. In the absence of a ZIKV vaccine or prophylactics, principal investigators (PIs) and international leaders in ZIKV research have formed the ZIKV Individual Participant Data (IPD) Consortium to identify, collect and synthesise IPD from longitudinal studies of pregnant women that measure ZIKV infection during pregnancy and fetal, infant or child outcomes.Methods and analysisWe will identify eligible studies through the ZIKV IPD Consortium membership and a systematic review and invite study PIs to participate in the IPD meta-analysis (IPD-MA). We will use the combined dataset to estimate the relative and absolute risk of congenital Zika syndrome (CZS), including microcephaly and late symptomatic congenital infections; identify and explore sources of heterogeneity in those estimates and develop and validate a risk prediction model to identify the pregnancies at the highest risk of CZS or adverse developmental outcomes. The variable accuracy of diagnostic assays and differences in exposure and outcome definitions means that included studies will have a higher level of systematic variability, a component of measurement error, than an IPD-MA of studies of an established pathogen. We will use expert testimony, existing internal and external diagnostic accuracy validation studies and laboratory external quality assessments to inform the distribution of measurement error in our models. We will apply both Bayesian and frequentist methods to directly account for these and other sources of uncertainty.Ethics and disseminationThe IPD-MA was deemed exempt from ethical review. We will convene a group of patient advocates to evaluate the ethical implications and utility of the risk stratification tool. Findings from these analyses will be shared via national and international conferences and through publication in open access, peer-reviewed journals.Trial registration numberPROSPERO International prospective register of systematic reviews (CRD42017068915).</jats:sec

    EVALITA Evaluation of NLP and Speech Tools for Italian - December 17th, 2020

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    Welcome to EVALITA 2020! EVALITA is the evaluation campaign of Natural Language Processing and Speech Tools for Italian. EVALITA is an initiative of the Italian Association for Computational Linguistics (AILC, http://www.ai-lc.it) and it is endorsed by the Italian Association for Artificial Intelligence (AIxIA, http://www.aixia.it) and the Italian Association for Speech Sciences (AISV, http://www.aisv.it)

    Un conductor de carga llamado ADN

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    Over the past few weeks, few media outlets have forgotten to dedicate a few words or special editions to the celebration of the 50th anniversary of the publication of the double helix model of deoxyribonucleic acid (DNA)Durante las últimas semanas pocos medios de comunicación han olvidado dedicar algunas palabras o ediciones especiales acerca de la celebración de los 50 años de la publicación del modelo de la doble hélice del ácido desoxirribonucleico (ADN)

    Multicolor Mechanofluorophores for the Quantitative Detection of Covalent Bond Scission in Polymers

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    The fracture of polymer materials is a multiscale process starting with the scission of a single molecular bond advancing to a site of failure within the bulk. Quantifying the bonds broken during this process remains a big challenge yet would help to understand the distribution and dissipation of macroscopic mechanical energy. We here show the design and synthesis of fluorogenic molecular optical force probes (mechanofluorophores) covering the entire visible spectrum in both absorption and emission. Their dual fluorescent character allows to track non-broken and broken bonds in dissolved and bulk polymers by fluorescence spectroscopy and microscopy. Importantly, we develop an approach to determine the absolute number and relative fraction of intact and cleaved bonds with high local resolution. We anticipate that our mechanofluorophores in combination with our quantification methodology will allow to quantitatively describe fracture processes in materials ranging from soft hydrogels to high-performance polymers. © 2021 The Authors. Angewandte Chemie International Edition published by Wiley-VCH Gmb

    Primer estudio de artropodofauna cadavérica sobre modelos experimentales porcinos en el noreste de la provincia del Chubut, Argentina

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    En este trabajo se estudió el proceso de descomposición y la composición de insectos presentes en biomodelos porcinos, en el NE de la provincia del Chubut. El objetivo fue determinar la composición específica, abundancia y riqueza de la artropodofauna carroñera en el ambiente de estepa. Se realizaron muestreos estacionales durante tres años consecutivos utilizándose tres cerdos domésticos para cada muestreo, colocados dentro de jaulas de madera cubiertas de alambre tejido. Diariamente se colectaron los artrópodos en el cuerpo, debajo y alrededor de este. Se registraron 36.157 individuos pertenecientes a 78 especies de 18 familias distribuidas entre los órdenes Diptera, Coleoptera e Hymenoptera. Se citan por primera vez de la provincia de Chubut tres especies de Calliphoridae: Paralucilia pseudolyrcea Mello, Paralucilia fulvinota Bigot y Chrysomya albiceps Wiedemann; y una especie de Muscidae: Arthurella choelensis Patitucci & Mariluis. Se incorpora como primera cita para la fauna cadavérica argentina a Sarcophaga (Lipoptilocnema) margaretae Lahille (Sarcophagidae). Se trata del primer estudio sobre entomología forense realizado en Patagonia que permite conocer los procesos de descomposición cadavérica y la fauna de insectos carroñeros presentes en esta zona. Por lo tanto, aporta información relevante que puede utilizarse en la resolución de casos forenses humanos en la región
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