150 research outputs found

    Sympatric otariids increase trophic segregation in response to warming ocean conditions in Peruvian Humboldt Current System

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    Determining trophic habits of predator communities is essential to measure interspecific interactions and response to environmental fluctuations. South American fur seals, Arctocephalus australis (SAFS) and sea lions Otaria byronia (SASL), coexist along the coasts of Peru. Recently, ocean warming events (2014–2017) that can decrease and impoverish prey biomass have occurred in the Peruvian Humboldt Current System. In this context, our aim was to assess the effect of warming events on long-term inter- and intra-specific niche segregation. We collected whisker from SAFS (55 females and 21 males) and SASL (14 females and 22 males) in Punta San Juan, Peru. We used δ13C and δ15N values serially archived in otariid whiskers to construct a monthly time series for 2005–2019. From the same period we used sea level anomaly records to determine shifts in the predominant oceanographic conditions using a change point analysis. Ellipse areas (SIBER) estimated niche width of species-sex groups and their overlap. We detected a shift in the environmental conditions marking two distinct periods (P1: January 2005—October 2013; P2: November 2013—December 2019). Reduction in δ15N in all groups during P2 suggests impoverished baseline values with bottom-up effects, a shift towards consuming lower trophic level prey, or both. Reduced overlap between all groups in P2 lends support of a more redundant assemblage during the colder P1 to a more trophically segregated assemblage during warmer P2. SASL females show the largest variation in response to the warming scenario (P2), reducing both ellipse area and δ15N mean values. Plasticity to adapt to changing environments and feeding on a more available food source without fishing pressure can be more advantageous for female SASL, albeit temporary trophic bottom-up effects. This helps explain larger population size of SASL in Peru, in contrast to the smaller and declining SAFS population

    Impacto de los factores de estrés en un programa quirúrgico basado en simulación oftálmica

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    Surgery; Ophthalmology; StressCirugía; Oftalmología; EstrésCirurgia; Oftalmologia; EstrésIntroduction Stress factors influence surgical procedures. This study aims to assess the impact of stress factors on surgical performance in ophthalmology simulation. Specifically, the study aims to identify which exercises are most affected by stress and to examine the relationship between stress levels, surgical complexity, and technical skills. Material and methods A prospective study of a cohort of 13 ophthalmology residents, at Vall Hebron University Hospital. All study participants received basic training before the study to become familiar with the simulator and surgical maneuvers. Once completed, the participants were invited to perform 3 defined exercises (E1, E2, and E3, increasing difficulty level from 1 to 3) in relaxed conditions. Afterwards, the same exercises were performed again under a stressful environment. The stress was created introducing physical, auditory, and interruptions factors. The results in technical skills were evaluated through the relaxation and stress scores, as well as the time required to complete the exercises under relaxation and stress conditions. A detailed metric was used to assess the variables in relation to stress situations, including physical stress, haste, the presence of background music, and scheduled interruptions. The results are expressed by median and interquartile range. To compare them, Wilcoxon test for paired samples and the Whitney U Test were performed. The results were stratified by year of residence (1–2 years vs 3–4 years). Results The stress score was significantly lower in the 3 exercises compared to the relax score (75 vs 86, 52 vs 90, 55 vs 61, respectively, p > .05). Time to perform the exercises was less predictable and was even lower in stressful situations with no statistical differences. Under stress, both younger and older residents scored worse on the more complex exercises. Conclusion Stress affects surgery with simulators. The most difficult exercises are the most likely to be affected by stress. These results suggest that through ophthalmic simulators ophthalmologists have the opportunity to train surgical stress and therefore improving patient safety.Introducción Los factores de estrés influyen en los procedimientos quirúrgicos. Este estudio tiene como objetivo evaluar el impacto de los factores de estrés en el desempeño quirúrgico en simulaciones oftalmológicas. Específicamente, el estudio busca identificar qué ejercicios se ven más afectados por el estrés y examinar la relación entre los niveles de estrés, la complejidad quirúrgica y las habilidades técnicas Materiales y métodos Estudio prospectivo de una cohorte de 13 residentes de oftalmología en el Hospital Universitario Vall Hebron. Todos los participantes del estudio recibieron entrenamiento básico antes del estudio para familiarizarse con el simulador y las maniobras quirúrgicas. Una vez completado, se invitó a los participantes a realizar tres ejercicios definidos (E1, E2, E3, aumentando el nivel de dificultad de 1 a 3) en condiciones relajadas. Posteriormente, los mismos ejercicios se realizaron nuevamente bajo un entorno estresante. El estrés se creó introduciendo factores físicos, auditivos e interrupciones. Los resultados en habilidades técnicas fueron evaluados mediante la puntuación de relajación y estrés, así como el tiempo requerido para completar los ejercicios bajo condiciones de relajación y estrés. Se utilizó una métrica detallada para evaluar las variables en relación con las situaciones de estrés, incluyendo el estrés físico, la prisa, la presencia de música ambiental e interrupciones programadas. Los resultados se expresan mediante la mediana y el rango intercuartílico. Para compararlos, se realizaron la prueba de Wilcoxon para muestras pareadas y la prueba U de Whitney. Los resultados se estratificaron por año de residencia (1-2 años vs. 3-4 años). Resultados La puntuación de estrés fue significativamente menor en los tres ejercicios en comparación con la puntuación de relajación (75 vs. 86, 52 vs. 90, 55 vs. 61 respectivamente, p > 0.05). El tiempo para realizar los ejercicios fue menos predecible y fue aún menor en situaciones estresantes sin diferencias estadísticas. Bajo estrés, tanto los residentes más jóvenes como los más avanzados obtuvieron peores puntuaciones en los ejercicios más complejos. Conclusión El estrés afecta a la cirugía con simuladores. Los ejercicios más difíciles son los más propensos a ser afectados por el estrés. Estos resultados sugieren que a través de simuladores oftálmicos, los oftalmólogos tienen la oportunidad de entrenar el estrés quirúrgico y por lo tanto mejorar la seguridad del paciente

    Zika vector competence data reveals risks of outbreaks: the contribution of the European ZIKAlliance project

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    First identified in 1947, Zika virus took roughly 70 years to cause a pandemic unusually associated with virus-induced brain damage in newborns. Zika virus is transmitted by mosquitoes, mainly Aedes aegypti, and secondarily, Aedes albopictus, both colonizing a large strip encompassing tropical and temperate regions. As part of the international project ZIKAlliance initiated in 2016, 50 mosquito populations from six species collected in 12 countries were experimentally infected with different Zika viruses. Here, we show that Ae. aegypti is mainly responsible for Zika virus transmission having the highest susceptibility to viral infections. Other species play a secondary role in transmission while Culex mosquitoes are largely non-susceptible. Zika strain is expected to significantly modulate transmission efficiency with African strains being more likely to cause an outbreak. As the distribution of Ae. aegypti will doubtless expand with climate change and without new marketed vaccines, all the ingredients are in place to relive a new pandemic of Zika.info:eu-repo/semantics/publishedVersio

    Zika vector competence data reveals risks of outbreaks: the contribution of the European ZIKAlliance project

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    First identified in 1947, Zika virus took roughly 70 years to cause a pandemic unusually associated with virus-induced brain damage in newborns. Zika virus is transmitted by mosquitoes, mainly Aedes aegypti, and secondarily, Aedes albopictus, both colonizing a large strip encompassing tropical and temperate regions. As part of the international project ZIKAlliance initiated in 2016, 50 mosquito populations from six species collected in 12 countries were experimentally infected with different Zika viruses. Here, we show that Ae. aegypti is mainly responsible for Zika virus transmission having the highest susceptibility to viral infections. Other species play a secondary role in transmission while Culex mosquitoes are largely non-susceptible. Zika strain is expected to significantly modulate transmission efficiency with African strains being more likely to cause an outbreak. As the distribution of Ae. aegypti will doubtless expand with climate change and without new marketed vaccines, all the ingredients are in place to relive a new pandemic of Zika

    EFESTO-2: European Flexible Heat Shields Advanced TPS Design and Tests for Future In-Orbit Demonstration - 2

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    EFESTO-2 is an EU-funded project under Horizon Europe that aims to enhance European expertise in Inflatable Heat Shields (IHS). Building on the achievements of the previous EFESTO project (H2020 funds No 821801), EFESTO-2 focuses on advancing key IHS technologies to increase their Technology Readiness Level (TRL). The project pillars include analyzing the business case for IHS applications, exploring additional aspects of IHS, improving tools and models, and establishing a development roadmap for IHS systems. This paper outlines the project objectives and plan, highlighting ongoing and future activities for the next two years, positioning it within the European re-entry technology roadmap. Funding was provided by the European Union's Horizon Europe program (grant agreement No 1010811041)

    EFESTO‑2: European Flexible Heat Shields Advanced TPS Design and Tests for Future In‑Orbit Demonstration‑2

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    EFESTO-2 is an EU-funded project under Horizon Europe that aims to enhance European expertise in Inflatable Heat Shields (IHS). Building on the achievements of the previous EFESTO project (H2020 funds No 821801), EFESTO-2 focuses on advancing key IHS technologies to increase their Technology Readiness Level (TRL). The project pillars include analysing the business case for IHS applications, exploring additional aspects of IHS, improving tools and models and establishing a development roadmap for IHS systems. This paper outlines the project objectives and plan, highlighting ongoing and future activities for the next 2 years, positioning it within the European re-entry technology roadmap. This project has received funding from the European Union's Horizon Europe program (grant agreement No 1010811041)

    Integrated photonic-based coronagraphic systems for future space telescopes

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    The detection and characterization of Earth-like exoplanets around Sun-like stars is a primary science motivation for the Habitable Worlds Observatory. However, the current best technology is not yet advanced enough to reach the 10^-10 contrasts at close angular separations and at the same time remain insensitive to low-order aberrations, as would be required to achieve high-contrast imaging of exo-Earths. Photonic technologies could fill this gap, potentially doubling exo-Earth yield. We review current work on photonic coronagraphs and investigate the potential of hybridized designs which combine both classical coronagraph designs and photonic technologies into a single optical system. We present two possible systems. First, a hybrid solution which splits the field of view spatially such that the photonics handle light within the inner working angle and a conventional coronagraph that suppresses starlight outside it. Second, a hybrid solution where the conventional coronagraph and photonics operate in series, complementing each other and thereby loosening requirements on each subsystem. As photonic technologies continue to advance, a hybrid or fully photonic coronagraph holds great potential for future exoplanet imaging from space.Comment: Conference Proceedings of SPIE: Techniques and Instrumentation for Detection of Exoplanets XI, vol. 12680 (2023

    Visible extreme adaptive optics on extremely large telescopes: Towards detecting oxygen in Proxima Centauri b and analogs

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    Looking to the future of exo-Earth imaging from the ground, core technology developments are required in visible extreme adaptive optics (ExAO) to enable the observation of atmospheric features such as oxygen on rocky planets in visible light. UNDERGROUND (Ultra-fast AO techNology Determination for Exoplanet imageRs from the GROUND), a collaboration built in Feb. 2023 at the Optimal Exoplanet Imagers Lorentz Workshop, aims to (1) motivate oxygen detection in Proxima Centauri b and analogs as an informative science case for high-contrast imaging and direct spectroscopy, (2) overview the state of the field with respect to visible exoplanet imagers, and (3) set the instrumental requirements to achieve this goal and identify what key technologies require further development.Comment: SPIE Proceeding: 2023 / 12680-6

    The CHEOPS mission

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    The CHaracterising ExOPlanet Satellite (CHEOPS) was selected in 2012, as the first small mission in the ESA Science Programme and successfully launched in December 2019. CHEOPS is a partnership between ESA and Switzerland with important contributions by ten additional ESA Member States. CHEOPS is the first mission dedicated to search for transits of exoplanets using ultrahigh precision photometry on bright stars already known to host planets. As a follow-up mission, CHEOPS is mainly dedicated to improving, whenever possible, existing radii measurements or provide first accurate measurements for a subset of those planets for which the mass has already been estimated from ground-based spectroscopic surveys and to following phase curves. CHEOPS will provide prime targets for future spectroscopic atmospheric characterisation. Requirements on the photometric precision and stability have been derived for stars with magnitudes ranging from 6 to 12 in the V band. In particular, CHEOPS shall be able to detect Earth-size planets transiting G5 dwarf stars in the magnitude range between 6 and 9 by achieving a photometric precision of 20 ppm in 6 hours of integration. For K stars in the magnitude range between 9 and 12, CHEOPS shall be able to detect transiting Neptune-size planets achieving a photometric precision of 85 ppm in 3 hours of integration. This is achieved by using a single, frame-transfer, back-illuminated CCD detector at the focal plane assembly of a 33.5 cm diameter telescope. The 280 kg spacecraft has a pointing accuracy of about 1 arcsec rms and orbits on a sun-synchronous dusk-dawn orbit at 700 km altitude. The nominal mission lifetime is 3.5 years. During this period, 20% of the observing time is available to the community through a yearly call and a discretionary time programme managed by ESA.Comment: Submitted to Experimental Astronom

    Electrodiagnostic subtyping in Guillain–Barré syndrome patients in the International Guillain–Barré Outcome Study

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    Background and purpose: Various electrodiagnostic criteria have been developed in Guillain–Barré syndrome (GBS). Their performance in a broad representation of GBS patients has not been evaluated. Motor conduction data from the International GBS Outcome Study (IGOS) cohort were used to compare two widely used criterion sets and relate these to diagnostic amyotrophic lateral sclerosis criteria. Methods: From the first 1500 patients in IGOS, nerve conduction studies from 1137 (75.8%) were available for the current study. These patients were classified according to nerve conduction studies criteria proposed by Hadden and Rajabally. Results: Of the 1137 studies, 68.3% (N = 777) were classified identically according to criteria by Hadden and Rajabally: 111 (9.8%) axonal, 366 (32.2%) demyelinating, 195 (17.2%) equivocal, 35 (3.1%) inexcitable and 70 (6.2%) normal. Thus, 360 studies (31.7%) were classified differently. The areas of differences were as follows: 155 studies (13.6%) classified as demyelinating by Hadden and axonal by Rajabally; 122 studies (10.7%) classified as demyelinating by Hadden and equivocal by Rajabally; and 75 studies (6.6%) classified as equivocal by Hadden and axonal by Rajabally. Due to more strictly defined cutoffs fewer patients fulfilled demyelinating criteria by Rajabally than by Hadden, making more patients eligible for axonal or equivocal classification by Rajabally. In 234 (68.6%) axonal studies by Rajabally the revised El Escorial (amyotrophic lateral sclerosis) criteria were fulfilled; in axonal cases by Hadden this was 1.8%. Conclusions and discussion: This study shows that electrodiagnosis in GBS is dependent on the criterion set utilized, both of which are based on expert opinion. Reappraisal of electrodiagnostic subtyping in GBS is warranted
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