154 research outputs found

    Preparation of biodegradable functionalized polyesters aimed to be used as surgical adhesives

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    The study and development of new biocompatible materials to be applied as UV-curable adhesives is extremely important to grant the preparation of matrices with suitable mechanical, biological and thermal properties with a fast curing rate. Herein, photocrosslinkable biodegradable copolymers composed of unsaturated polyesters (UP) and lactic acid oligomers functionalized with 2-isocyanatoethyl methacrylate (IEMA) were produced. Henceforth, three different stoichiometric proportions were tested, which, after the addition of a biocompatible photoinitiator (IrgacureÂź 2959), resulted in flexible, resistant and uniform matrices after 2 minutes and 30 seconds of crosslinking. The synthesized materials were then further characterized in terms of chemical composition and thermal/mechanical behaviour. The gel content, dynamic contact angles, water sorption capacity and hydrolytic degradation were also assessed. The biocompatibility and antibacterial activity of the produced materials was also evaluated. Taking into account all the data obtained, it may be concluded that the new synthesized biodegradable bioadhesives present promising properties to be used as surgical adhesives.info:eu-repo/semantics/acceptedVersio

    Tuberculosis infection in children visiting friends and relatives in countries with high incidence of tuberculosis : A study protocol

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    Tuberculosis (TB) is a global infectious disease. In low-incidence countries, paediatric TB affects mostly immigrant children and children of immigrants. We hypothesize that these children are at risk of exposure to Mycobacterium tuberculosis when they travel to the country of origin of their parents to visit friends and relatives (VFR). In this study, we aim to estimate the incidence rate and risk factors associated to latent tuberculosis infection (LTBI) and TB in VFR children. A prospective study will be carried out in collaboration with 21 primary health care centres (PCC) and 5 hospitals in Catalonia, Spain. The study participants are children under 15 years of age, either immigrant themselves or born to immigrant parents, who travel to countries with high incidence of TB (≄ 40 cases/100,000 inhabitants). A sample size of 492 children was calculated. Participants will be recruited before traveling, either during a visit to a travel clinic or to their PCC, where a questionnaire including sociodemographic, epidemiological and clinical data will be completed, and a tuberculin skin test (TST) will be performed and read after 48 to 72 hours; patients with a positive TST at baseline will be excluded. A visit will be scheduled eight to twelve-weeks after their return to perform a TST and a QuantiFERON-TB Gold Plus test. The incidence rate of LTBI will be estimated per individual/month and person/year per country visited, and also by age-group. The study protocol was approved by the Clinical Research Ethics Committee of the Hospital Universitari MĂștua Terrassa (code 02/16) and the Clinical Research Ethics Committee of the FundaciĂł Institut Universitari per a la Recerca a l'AtenciĂł PrimĂ ria de Salut Jordi Gol i Gurina (code P16/094). Articles will be published in indexed scientific journals

    Cosmology and fundamental physics with the ELT-ANDES spectrograph

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    State-of-the-art 19th century spectroscopy led to the discovery of quantum mechanics, and 20th century spectroscopy led to the confirmation of quantum electrodynamics. State-of-the-art 21st century astrophysical spectrographs, especially ANDES at ESO’s ELT, have another opportunity to play a key role in the search for, and characterization of, the new physics which is known to be out there, waiting to be discovered. We rely on detailed simulations and forecast techniques to discuss four important examples of this point: big bang nucleosynthesis, the evolution of the cosmic microwave background temperature, tests of the universality of physical laws, and a real-time model-independent mapping of the expansion history of the universe (also known as the redshift drift). The last two are among the flagship science drivers for the ELT. We also highlight what is required for the ESO community to be able to play a meaningful role in 2030s fundamental cosmology and show that, even if ANDES only provides null results, such ‘minimum guaranteed science’ will be in the form of constraints on key cosmological paradigms: these are independent from, and can be competitive with, those obtained from traditional cosmological probes
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