44 research outputs found

    Unbound states of neutron-rich carbon isotopes

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    We work upon the model of a two-state mixing of states of pure proton and pure neutron excitation to describe excited 2+ states in carbon isotopes. The first 2+ state of 16C has been measured in other works showing it is dominated by neutron excitations and was recently confirmed in a study that has determined the proton amplitude of the first 2+ state for 16C, 18C and 20C. The aim of this thesis is to identify the mixed-symmetry 2+ state, which is above the neutron separation energy and therefore unbound. Its observation will add weight to our simple picture of describing the neutron-rich C isotopic chain, giving us great insights into the shell evolution towards the neutron dripline at Z=6. For that purpose, an experiment was carried out at GSI with the R3B/LAND setup in order to investigate the structure of unbound states of 16C, 18C and 20C for the first time via quasi-free scattering (p, 2p) reactions from 17N, 19N, and 21N, respectively. In this work, the results of the invariant-mass spectroscopy of the one neutron evaporation decay of 16C and 18C are presented, reporting three resonant states located at 5.71(06), 7.83(41) and 9.78(88) MeV for 16C and four unbound states observed at 5.54(10), 7.51(20), 9.83(33) and 12.31(30) MeV for 18C. These unbound states are discussed in comparison with shell model calculations performed with WBP, WBT and WBT* interactions. Preliminary exclusive cross sections are also presented for all of these states

    Quasi-free (p,2p) reactions in inverse kinematics for studying the fission yield dependence on temperature

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    Despite the recent experimental and theoretical progress in the investigation of the nuclear fission process, a complete description still represents a challenge in nuclear physics because it is a very complex dynamical process, whose description involves the coupling between intrinsic and collective degrees of freedom, as well as different quantum-mechanical phenomena. To improve on the existing data on nuclear fission,we produce fission reactions of heavy nuclei in inverse kinematics by using quasi-free (p,2p) scattering, which induce fission through particle-hole excitations that can range from few to ten\u27s of MeV. The measurement of the four-momenta of the two outgoing protons allows to reconstruct the excitation energy of the fissioning nucleus and therefore to study the evolution of the fission yields with temperature. The realization of this kind of experiment requires a complex experimental setup, providing full isotopic identification of both fission fragments and an accurate measurement of the momenta of the two outgoing protons. This was realized recently at the GSI/FAIR facility and here some preliminary results are presented

    Study protocol for the multicentre cohorts of Zika virus infection in pregnant women, infants, and acute clinical cases in Latin America and the Caribbean: The ZIKAlliance consortium

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    Background: The European Commission (EC) Horizon 2020 (H2020)-funded ZIKAlliance Consortium designed a multicentre study including pregnant women (PW), children (CH) and natural history (NH) cohorts. Clinical sites were selected over a wide geographic range within Latin America and the Caribbean, taking into account the dynamic course of the ZIKV epidemic. Methods: Recruitment to the PW cohort will take place in antenatal care clinics. PW will be enrolled regardless of symptoms and followed over the course of pregnancy, approximately every 4 weeks. PW will be revisited at delivery (or after miscarriage/abortion) to assess birth outcomes, including microcephaly and other congenital abnormalities according to the evolving definition of congenital Zika syndrome (CZS). After birth, children will be followed for 2 years in the CH cohort. Follow-up visits are scheduled at ages 1-3, 4-6, 12, and 24 months to assess neurocognitive and developmental milestones. In addition, a NH cohort for the characterization of symptomatic rash/fever illness was designed, including follow-up to capture persisting health problems. Blood, urine, and other biological materials will be collected, and tested for ZIKV and other relevant arboviral diseases (dengue, chikungunya, yellow fever) using RT-PCR or serological methods. A virtual, decentralized biobank will be created. Reciprocal clinical monitoring has been established between partner sites. Substudies of ZIKV seroprevalence, transmissio

    Coulomb dissociation of O-16 into He-4 and C-12

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    We measured the Coulomb dissociation of O-16 into He-4 and C-12 within the FAIR Phase-0 program at GSI Helmholtzzentrum fur Schwerionenforschung Darmstadt, Germany. From this we will extract the photon dissociation cross section O-16(alpha,gamma)C-12, which is the time reversed reaction to C-12(alpha,gamma)O-16. With this indirect method, we aim to improve on the accuracy of the experimental data at lower energies than measured so far. The expected low cross section for the Coulomb dissociation reaction and close magnetic rigidity of beam and fragments demand a high precision measurement. Hence, new detector systems were built and radical changes to the (RB)-B-3 setup were necessary to cope with the high-intensity O-16 beam. All tracking detectors were designed to let the unreacted O-16 ions pass, while detecting the C-12 and He-4

    Global disparities in surgeons’ workloads, academic engagement and rest periods: the on-calL shIft fOr geNEral SurgeonS (LIONESS) study

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    : The workload of general surgeons is multifaceted, encompassing not only surgical procedures but also a myriad of other responsibilities. From April to May 2023, we conducted a CHERRIES-compliant internet-based survey analyzing clinical practice, academic engagement, and post-on-call rest. The questionnaire featured six sections with 35 questions. Statistical analysis used Chi-square tests, ANOVA, and logistic regression (SPSS® v. 28). The survey received a total of 1.046 responses (65.4%). Over 78.0% of responders came from Europe, 65.1% came from a general surgery unit; 92.8% of European and 87.5% of North American respondents were involved in research, compared to 71.7% in Africa. Europe led in publishing research studies (6.6 ± 8.6 yearly). Teaching involvement was high in North America (100%) and Africa (91.7%). Surgeons reported an average of 6.7 ± 4.9 on-call shifts per month, with European and North American surgeons experiencing 6.5 ± 4.9 and 7.8 ± 4.1 on-calls monthly, respectively. African surgeons had the highest on-call frequency (8.7 ± 6.1). Post-on-call, only 35.1% of respondents received a day off. Europeans were most likely (40%) to have a day off, while African surgeons were least likely (6.7%). On the adjusted multivariable analysis HDI (Human Development Index) (aOR 1.993) hospital capacity > 400 beds (aOR 2.423), working in a specialty surgery unit (aOR 2.087), and making the on-call in-house (aOR 5.446), significantly predicted the likelihood of having a day off after an on-call shift. Our study revealed critical insights into the disparities in workload, access to research, and professional opportunities for surgeons across different continents, underscored by the HDI

    Notas Breves

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    Coulomb dissociation of 16O into 4He and 12C

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    We measured the Coulomb dissociation of 16O into 4He and 12C at the R3B setup in a first campaign within FAIR Phase 0 at GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt. The goal was to improve the accuracy of the experimental data for the 12C(a,?)16O fusion reaction and to reach lower center-ofmass energies than measured so far. The experiment required beam intensities of 109 16O ions per second at an energy of 500 MeV/nucleon. The rare case of Coulomb breakup into 12C and 4He posed another challenge: The magnetic rigidities of the particles are so close because of the same mass-To-charge-number ratio A/Z = 2 for 16O, 12C and 4He. Hence, radical changes of the R3B setup were necessary. All detectors had slits to allow the passage of the unreacted 16O ions, while 4He and 12C would hit the detectors' active areas depending on the scattering angle and their relative energies. We developed and built detectors based on organic scintillators to track and identify the reaction products with sufficient precision

    Nuevos escenarios para la docencia universitaria : entornos híbridos y pedagogías emergentes.

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    Memorias del IX Simposio Internacional de Docencia Universitaria (SIDU)Los trabajos reunidos en esta Memoria representan una contribución importante al campo de la educación y de la docencia universitaria, en tanto muestran distintas maneras de responder a las problemáticas educativas cotidianas y presentan propuestas para afrontar los retos emergentes en el campo de la educación superior. Invitamos a los lectores a realizar una lectura atenta y crítica de los trabajos compilados en esta publicación. Estamos seguros de que este acercamiento propiciará la reflexión y el análisis riguroso de los objetos de estudio abordados por los autores, y estimulará la generación de nuevos proyectos de investigación, intervención e innovación educativa que incidan en el desarrollo de mejores prácticas de docencia en educación media superior y superior.Pimera edición digitaldoi.org/10.56019/EDU-CETYS.2024.182

    Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

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    Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

    Análisis de vulnerabilidades y capacidades, psicosociales y ambientales, en materia de prevención y atención de emergencias ante eventos adversos, en la zona de Santa Teresa de Cóbano, durante el año 2017

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    Este documento pretende visualizar los resultados del trabajo final de graduación, en modalidad de seminario de graduación, denominado “Análisis de vulnerabilidades y capacidades psicosociales y ambientales, en materia de prevención y atención de emergencias ante eventos adversos, en la comunidad de Santa Teresa de Cóbano”. Dicho seminario está respaldado por el proyecto de investigación Crónica de un terremoto anunciado: la reconstrucción de la memoria colectiva sobre el terremoto de Nicoya del 5 de setiembre del 2012, de manera que es un seguimiento de la intervención que realizó la Brigada de Atención Psicosocial en Situaciones de Desastres y Emergencias, en distintas zonas de Guanacaste y Puntarenas, luego del terremoto del 2012. El objetivo es identificar las vulnerabilidades y capacidades, psicosociales y ambientales, en la zona de Santa Teresa de Cóbano. Para lo anterior, se realizaron entrevistas y talleres con organizaciones formales instaladas en la comunidad; además, se sistematizó la información y se realizaron dos devoluciones parciales en la comunidad y ante las instituciones, para validar la información y generar una propuesta de participación y fortalecimiento de las capacidades instaladas. De los resultados destaca que las organizaciones reconocen la necesidad de prepararse ante eventos adversos, sin embargo no lo realizan para no afectar la principal actividad económica, el turismo. Asimismo, se evidencia la heterogeneidad presente en la comunidad y la gran presencia de migrantes, la ruptura en el sentido de pertenencia, así como la fractura en los lazos sociales y la pérdida de identidad. A esto, se le añade la dificultad de organización, participación y seguimiento de proyectos comunitarios, lo que desemboca en el desinterés y la desarticulación de la comunidad en involucrarse. Además se identifican problemáticas como actividades delictivas, deserción escolar, alto costo de la vida, acceso casi nulo al agua potable, disposición inadecuada de las aguas residuales, manejo de residuos sólidos, falta de ordenamiento territorial; así como la ausencia de acompañamiento psicosocial en los procesos comunitarios.UCR::Vicerrectoría de Docencia::Ciencias Sociales::Facultad de Ciencias Sociales::Escuela de PsicologíaUCR::Vicerrectoría de Docencia::Salud::Facultad de Medicina::Escuela de Tecnologías en Salu
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