337 research outputs found

    Measurements of the atmospheric neutrino flux by Super-Kamiokande: energy spectra, geomagnetic effects, and solar modulation

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    A comprehensive study on the atmospheric neutrino flux in the energy region from sub-GeV up to several TeV using the Super-Kamiokande water Cherenkov detector is presented in this paper. The energy and azimuthal spectra of the atmospheric νe+νˉe{\nu}_e+{\bar{\nu}}_e and νμ+νˉμ{\nu}_{\mu}+{\bar{\nu}}_{\mu} fluxes are measured. The energy spectra are obtained using an iterative unfolding method by combining various event topologies with differing energy responses. The azimuthal spectra depending on energy and zenith angle, and their modulation by geomagnetic effects, are also studied. A predicted east-west asymmetry is observed in both the νe{\nu}_e and νμ{\nu}_{\mu} samples at 8.0 {\sigma} and 6.0 {\sigma} significance, respectively, and an indication that the asymmetry dipole angle changes depending on the zenith angle was seen at the 2.2 {\sigma} level. The measured energy and azimuthal spectra are consistent with the current flux models within the estimated systematic uncertainties. A study of the long-term correlation between the atmospheric neutrino flux and the solar magnetic activity cycle is also performed, and a weak indication of a correlation was seen at the 1.1 {\sigma} level, using SK I-IV data spanning a 20 year period. For particularly strong solar activity periods known as Forbush decreases, no theoretical prediction is available, but a deviation below the typical neutrino event rate is seen at the 2.4 {\sigma} level.Comment: 30 pages, 31 figure

    Solar Neutrino Measurements in Super-Kamiokande-IV

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    Upgraded electronics, improved water system dynamics, better calibration and analysis techniques allowed Super-Kamiokande-IV to clearly observe very low-energy 8B solar neutrino interactions, with recoil electron kinetic energies as low as 3.49 MeV. Super-Kamiokande-IV data-taking began in September of 2008; this paper includes data until February 2014, a total livetime of 1664 days. The measured solar neutrino flux is (2.308+-0.020(stat.) + 0.039-0.040(syst.)) x 106/(cm2sec) assuming no oscillations. The observed recoil electron energy spectrum is consistent with no distortions due to neutrino oscillations. An extended maximum likelihood fit to the amplitude of the expected solar zenith angle variation of the neutrino-electron elastic scattering rate in SK-IV results in a day/night asymmetry of (-3.6+-1.6(stat.)+-0.6(syst.))%. The SK-IV solar neutrino data determine the solar mixing angle as sin2 theta_12 = 0.327+0.026-0.031, all SK solar data (SK-I, SK-II, SK III and SKIV) measures this angle to be sin2 theta_12 = 0.334+0.027-0.023, the determined mass-squared splitting is Delta m2_21 = 4.8+1.5-0.8 x10-5 eV2.Comment: Submitted to Physical Review D; 23 pages, 40 figure

    Search for astronomical neutrinos from blazar TXS 0506+056 in super-kamiokande

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    We report a search for astronomical neutrinos in the energy region from several GeV to TeV in the direction of the blazar TXS 0506+056 using the Super-Kamiokande detector following the detection of a 100 TeV neutrinos from the same location by the IceCube collaboration. Using Super-Kamiokande neutrino data across several data samples observed from 1996 April to 2018 February we have searched for both a total excess above known backgrounds across the entire period as well as localized excesses on smaller timescales in that interval. No significant excess nor significant variation in the observed event rate are found in the blazar direction. Upper limits are placed on the electron- and muon-neutrino fluxes at the 90% confidence level as 6.0 × 10−7 and 4.5 × 10−7–9.3 × 10−10 [erg cm−2 s−1], respectively

    Why Are Outcomes Different for Registry Patients Enrolled Prospectively and Retrospectively? Insights from the Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF).

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    Background: Retrospective and prospective observational studies are designed to reflect real-world evidence on clinical practice, but can yield conflicting results. The GARFIELD-AF Registry includes both methods of enrolment and allows analysis of differences in patient characteristics and outcomes that may result. Methods and Results: Patients with atrial fibrillation (AF) and ≥1 risk factor for stroke at diagnosis of AF were recruited either retrospectively (n = 5069) or prospectively (n = 5501) from 19 countries and then followed prospectively. The retrospectively enrolled cohort comprised patients with established AF (for a least 6, and up to 24 months before enrolment), who were identified retrospectively (and baseline and partial follow-up data were collected from the emedical records) and then followed prospectively between 0-18 months (such that the total time of follow-up was 24 months; data collection Dec-2009 and Oct-2010). In the prospectively enrolled cohort, patients with newly diagnosed AF (≤6 weeks after diagnosis) were recruited between Mar-2010 and Oct-2011 and were followed for 24 months after enrolment. Differences between the cohorts were observed in clinical characteristics, including type of AF, stroke prevention strategies, and event rates. More patients in the retrospectively identified cohort received vitamin K antagonists (62.1% vs. 53.2%) and fewer received non-vitamin K oral anticoagulants (1.8% vs . 4.2%). All-cause mortality rates per 100 person-years during the prospective follow-up (starting the first study visit up to 1 year) were significantly lower in the retrospective than prospectively identified cohort (3.04 [95% CI 2.51 to 3.67] vs . 4.05 [95% CI 3.53 to 4.63]; p = 0.016). Conclusions: Interpretations of data from registries that aim to evaluate the characteristics and outcomes of patients with AF must take account of differences in registry design and the impact of recall bias and survivorship bias that is incurred with retrospective enrolment. Clinical Trial Registration: - URL: http://www.clinicaltrials.gov . Unique identifier for GARFIELD-AF (NCT01090362)

    Physics Potentials with the Second Hyper-Kamiokande Detector in Korea

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    We have conducted sensitivity studies on an alternative configuration of the Hyper-Kamiokande experiment by locating the 2nd Hyper-Kamiokande detector in Korea at \sim1100 -\ 1300 km baseline. Having two detectors at different baselines improves sensitivity to leptonic CP violation, neutrino mass ordering as well as nonstandard neutrino interactions. There are several candidate sites in Korea with greater than 1 km high mountains ranged at an 1-3 degree off-axis angle. Thanks to larger overburden of the candidate sites in Korea, low energy physics, such as solar and supernova neutrino physics as well as dark matter search, is expected to be improved. In this paper sensitivity studies on the CP violation phase and neutrino mass ordering are performed using current T2K systematic uncertainties in most cases. We plan to improve our sensitivity studies in the near future with better estimation of our systematic uncertainties

    Vías clínicas para el cuidado oral en pacientes sometidos a extracción de injerto de mucosa oral: una revisión sistemática

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    Introduction: Oral mucosal grafts are essential in reconstructive urology, particularly for urethral and genital defects. Advances in harvesting and implantation techniques have been made, yet perioperative care remains crucial for optimal outcomes. This systematic review explores postoperative care pathways following oral mucosal graft harvesting to consolidate knowledge, identify best practices, and highlight research gaps. Objective: The review aims to identify optimal care pathways, compare different oral care approaches, and address research gaps. Methods: A systematic literature search was conducted using PubMed, Scopus, and Web of Science databases without time constraints. Key search terms included "oral mucosal graft", "oral care pathways", "OMG post-operative care", "BMG", "LMG", and "OMG graft harvesting". Selection followed PRISMA guidelines. Inclusion criteria focused on studies addressing oral mucosal grafts in reconstructive urology and associated perioperative care, excluding non-English articles, case reports, and editorials. Results: The review underscores the suitability of oral mucosa for grafting due to properties like excellent vascularization and minimal immunogenicity. Comparisons among graft harvesting sites reveal differences in tissue quality, ease of harvest, and donor site morbidity. Non-closure techniques generally result in less postoperative pain and quicker healing, though closure might better control bleeding and infection. Despite common complications such as mild trismus and altered chewing efficiency, patient satisfaction remains high. Conclusions: Effective management of oral mucosal grafts harvesting emphasizes tailored perioperative care to minimize complications and enhance recovery. Further research should focus on long-term oral morbidity, standardized care protocols, and patient-reported outcomes to improve care pathways and surgical results.Introducción: Los injertos de mucosa oral constituyen un elemento esencial en el campo de la urología reconstructiva, especialmente para el tratamiento de defectos uretrales y genitales. Aunque se han producido avances en las técnicas de extracción e implantación, el manejo perioperatorio sigue desempeñando un papel crucial en la obtención de resultados óptimos. Esta revisión sistemática explora las vías clínicas para el cuidado postoperatorio tras la extracción de un injerto de mucosa oral, con el fin de consolidar los conocimientos, identificar las mejores prácticas y arrojar luz sobre los vacíos de investigación. Objetivo: El objetivo de esta revisión es identificar las vías de atención óptimas, comparar diferentes enfoques para el cuidado oral y abordar los vacíos existentes en la investigación. Métodos Se realizó una búsqueda bibliográfica sistemática en las bases de datos PubMed, Scopus y Web of Science sin limitaciones de tiempo. Los términos clave de búsqueda incluyeron «oral mucosal graft», «oral care pathways», «OMG post-operative care», «BMG», «LMG» y «OMG graft harvesting». La selección se realizó según las directrices PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses). Se incluyeron los estudios que abordaban el uso de injertos de mucosa oral en urología reconstructiva y las medidas de cuidado perioperatorio asociadas, y se excluyeron los artículos no redactados en inglés, los informes de casos y los editoriales. Resultados: La revisión pone de manifiesto la idoneidad del injerto procedente de mucosa oral gracias a sus propiedades de excelente vascularización e inmunogenicidad mínima. Las comparaciones entre las distintas zonas donantes de injertos desvelan diferencias en la calidad del tejido, la facilidad de extracción y la morbilidad de la zona donante. Aunque se cree que el cierre del lecho quirúrgico podría mejorar el control de la hemorragia y de las infecciones, las técnicas de cicatrización por segunda intención suelen producir menos dolor postoperatorio y una cicatrización más rápida. A pesar de las complicaciones habituales, como el trismo leve y la alteración de la eficacia masticatoria, la satisfacción de los pacientes sigue siendo alta. Conclusiones: El abordaje eficaz de la extracción de injertos de mucosa oral destaca la necesidad de unos cuidados perioperatorios individualizados para minimizar las complicaciones y optimizar la recuperación. Los estudios futuros deben centrarse en la morbilidad oral a largo plazo, los protocolos de atención estandarizados y los resultados comunicados por los pacientes para mejorar las vías de atención y los resultados quirúrgicos

    Chaoborus and Gasterosteus Anti-Predator Responses in Daphnia pulex Are Mediated by Independent Cholinergic and Gabaergic Neuronal Signals

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    Many prey species evolved inducible defense strategies that protect effectively against predation threats. Especially the crustacean Daphnia emerged as a model system for studying the ecology and evolution of inducible defenses. Daphnia pulex e.g. shows different phenotypic adaptations against vertebrate and invertebrate predators. In response to the invertebrate phantom midge larvae Chaoborus (Diptera) D. pulex develops defensive morphological defenses (neckteeth). Cues originating from predatory fish result in life history changes in which resources are allocated from somatic growth to reproduction. While there are hints that responses against Chaoborus cues are transmitted involving cholinergic neuronal pathways, nothing is known about the neurophysiology underlying the transmission of fish related cues. We investigated the neurophysiological basis underlying the activation of inducible defenses in D. pulex using induction assays with the invertebrate predator Chaoborus and the three-spined stickleback Gasterosteus aculeatus. Predator-specific cues were combined with neuro-effective substances that stimulated or inhibited the cholinergic and gabaergic nervous system. We show that cholinergic-dependent pathways are involved in the perception and transmission of Chaoborus cues, while GABA was not involved. Thus, the cholinergic nervous system independently mediates the development of morphological defenses in response to Chaoborus cues. In contrast, only the inhibitory effect of GABA significantly influence fish-induced life history changes, while the application of cholinergic stimulants had no effect in combination with fish related cues. Our results show that cholinergic stimulation mediates signal transmission of Chaoborus cues leading to morphological defenses. Fish cues, which are responsible for predator-specific life history adaptations involve gabaergic control. Our study shows that both pathways are independent and thus potentially allow for adjustment of responses to variable predation regimes

    Theia: an advanced optical neutrino detector

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    New developments in liquid scintillators, high-efficiency, fast photon detectors, and chromatic photon sorting have opened up the possibility for building a large-scale detector that can discriminate between Cherenkov and scintillation signals. Such a detector could reconstruct particle direction and species using Cherenkov light while also having the excellent energy resolution and low threshold of a scintillator detector. Situated deep underground, and utilizing new techniques in computing and reconstruction, this detector could achieve unprecedented levels of background rejection, enabling a rich physics program spanning topics in nuclear, high-energy, and astrophysics, and across a dynamic range from hundreds of keV to many GeV. The scientific program would include observations of low- and high-energy solar neutrinos, determination of neutrino mass ordering and measurement of the neutrino CP-violating phase δ, observations of diffuse supernova neutrinos and neutrinos from a supernova burst, sensitive searches for nucleon decay and, ultimately, a search for neutrinoless double beta decay, with sensitivity reaching the normal ordering regime of neutrino mass phase space. This paper describes Theia, a detector design that incorporates these new technologies in a practical and affordable way to accomplish the science goals described above

    Evidence of antineutrinos from distant reactors using pure water at SNO

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    The SNO+ Collaboration reports the first evidence of reactor antineutrinos in a Cherenkov detector. The nearest nuclear reactors are located 240 km away in Ontario, Canada. This analysis uses events with energies lower than in any previous analysis with a large water Cherenkov detector. Two analytical methods are used to distinguish reactor antineutrinos from background events in 190 days of data and yield consistent evidence for antineutrinos with a combined significance of 3.5σ
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