26 research outputs found

    Resonance refraction and neutrino oscillations

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    The refraction index and matter potential depend on neutrino energy and this dependence has a resonance character associated to the production of the mediator in the ss-channel. For light mediators and light particles of medium (background) the resonance can be realized at energies accessible to laboratory experiments. We study properties of the energy dependence of the potential for different C-asymmetries of background. Interplay of the background potential and the vacuum term leads to (i) bump in the oscillation probability in the resonance region, (ii) dip related to the MSW resonance in the background, (iii) substantial deviation of the effective Δm2\Delta m^2 above the resonance from the low energy value, etc. We considered generation of mixing in the background. Interactions with background shifts the energy of usual MSW resonance and produces new MSW resonances. Searches of the background effects allow us to put bounds on new interactions of neutrinos and properties of the background. We show that explanation of the MiniBooNE excess, as the bump due to resonance refraction, is excluded.Comment: 36 pages, 6 figure

    Comprehensive Measurement Forecasts of the EeV Neutrino-Nucleon Cross Section with Cosmic Neutrinos at IceCube-Gen2

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    The investigation of neutrino interactions with matter serves as a valuable tool for understanding the fundamental structure of nucleons and potentially uncovering novel physics phenomena. To date, the neutrino-nucleon cross section has been examined across a range of energies spanning from a few hundred MeV to PeV. However, the pursuit of ultra-high-energy (UHE) cosmic neutrinos, surpassing 100 PeV in energy, holds the promise of further advancements. In the next 10-20 years, UHE neutrino telescopes, currently in the planning stage, may ultimately succeed in their detection. This article presents pioneering and comprehensive estimation forecasts for the ultra-high-energy neutrino-nucleon cross section, with a specific focus on the employment of neutrino radio-detection within the IceCube-Gen2 experiment. The study incorporates cutting-edge methodologies in UHE neutrino flux prediction, neutrino propagation within the Earth, radio detection techniques, and the treatment of background data to facilitate accurate cross section measurement projections. Assuming the successful detection of at least a few tens of UHE neutrino-induced events over a 10-year period, IceCube-Gen2 could achieve, for the first time, the measurement of the cross section at center-of-mass energies of approximately s10\sqrt{s} \approx 10--100 TeV. Furthermore, if the number of events exceeds one hundred, the precision of the cross section measurement could be comparable to its corresponding theoretical prediction.Comment: 8 pages, 4 figures, 2 figures. Submitted as a proceeding for ICRC 202

    Discovery Forecasts of the Diffuse Ultra-High-Energy Neutrino Flux with IceCube-Gen2

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    The discovery of ultra-high-energy (UHE) neutrinos has the potential to offer unique insight into fundamental questions. To capitalize on the upcoming opportunity provided by new UHE neutrino telescopes, we provide state-of-the-art forecasts of the discovery of a diffuse flux of UHE neutrinos over the next 10-20 years, focusing on neutrino radio-detection in the planned IceCube-Gen2 detector. We use state-of-the-art flux predictions and detector modeling. We find that, even under conservative analysis choices, most benchmark UHE neutrino flux models from the literature may be discovered within 10 years of detector exposure, with many discoverable sooner, and may be distinguished from each other. Our results demonstrate the transformative potential of next-generation UHE neutrino telescopes.Comment: 8 pages, 3 figures. Submitted as a proceeding for ICRC 2023. arXiv admin note: text overlap with arXiv:2210.0375

    Joint measurement of the ultra-high-energy neutrino spectrum and cross section

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    Soon, a new generation of neutrino telescopes, presently under planning, will target the discovery of ultra-high-energy (UHE) neutrinos of cosmic origin, with energies higher than 100 PeV, that promise unique insight into astrophysics and particle physics. Yet, predictions of the UHE neutrino flux and interaction cross section -- whose measurement is co-dependent -- are laden with significant uncertainty that, if unaddressed, could misrepresent the capabilities to measure one or the other. To address this, we advocate for the joint measurement of the UHE neutrino spectrum and neutrino-nucleon cross section, including of their energy dependence, without assuming prior knowledge of either. We illustrate our methods by adopting empirical parametrizations of the neutrino spectrum, in forecasts geared to the planned radio array of the IceCube-Gen2 neutrino telescope. We warn against using simple parametrizations -- a simple power law or one augmented with an exponential cut-off -- that might fail to capture features of the spectrum that are commonplace in the predictions. We argue instead for the use of flexible parametrizations -- a piecewise power law or an interpolating polynomial -- that ensure accuracy. We report loose design targets for the detector energy and angular resolution that are compatible with those under present consideration.Comment: 20 pages, 5 figures, 1 tabl

    Near-future discovery of point sources of ultra-high-energy neutrinos

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    Upcoming neutrino telescopes may discover ultra-high-energy (UHE) cosmic neutrinos, with energies beyond 100 PeV, in the next 10--20 years. Finding their sources would expose the long-sought origin of UHE cosmic rays. We search for sources by looking for multiplets of UHE neutrinos arriving from similar directions. Our forecasts are state-of-the-art, geared at neutrino radio-detection in IceCube-Gen2. They account for detector energy and angular response, and for critical, but uncertain backgrounds. We report powerful insight. Sources at declination of 45-45^\circ to 00^\circ will be easiest to discover. Discovering even one steady-state source in 10~years would disfavor most known steady-state source classes as dominant. Discovering no transient source would disfavor most known transient source classes as dominant. Our results aim to inform the design of upcoming detectors.Comment: 4 pages, 2 figures, plus references and technical appendice

    Treatment of hypertension with angiotensin-converting enzyme inhibitors or angiotensin receptor blockers and resting metabolic rate: A cross-sectional study

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    Hypertension in obese and overweight patients is associated with an elevated resting metabolic rate (RMR). The aim of this study was to determine whether RMR is reduced in hypertensive patients treated with angiotensin-converting enzyme inhibitors (ACEI) and blockers (ARB). The RMR was determined by indirect calorimetry in 174 volunteers; 93 (46.5 %) were hypertensive, of which 16 men and 13 women were treated with ACEI/ARB, while 30 men and 19 women with untreated hypertension served as a control group. Treated and untreated hypertensives had similar age, BMI, physical activity, and cardiorespiratory fitness. The RMR normalized to the lean body mass (LBM) was 15% higher in the untreated than ACEI/ARB-treated hypertensive women (p = .003). After accounting for LBM, whole-body fat mass, age, the double product (heart rate x systolic blood pressure), and the distance walked per day, the RMR was 2.9% lower in the patients taking ACEI/ARB (p = .26, treatment x sex interaction p = .005). LBM, age, and the double product explained 78% of the variability in RMR (R2 = 0.78, p < .001). In contrast, fat mass, the distance walked per day, and total T4 or TSH did not add predictive power to the model. Compared to men, a greater RMR per kg of LBM was observed in untreated hypertensive overweight and obese women, while this sex difference was not observed in patients treated with ACEI or ARBs. In conclusion, our results indicate that elevated RMR per kg of LBM may be normalized by antagonizing the renin-angiotensin system

    The diagnostic importance of species specific and cross-reactive components of Taenia solium, Echinococcus granulosus, and Hymenolepis nana Importância diagnóstica da reação cruzada espécie-específica de componentes da Taenia solium, Echinococcus granulosus e Hymenolepis nana

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    Sera from patients infected with Taenia solium, Hymenolepis nana and Echinococcus granulosus were tested against homologous and heterologous parasite antigens using an ELISA assay, and a high degree of cross-reactivity was verified. To identify polypeptides responsible for this cross reactivity, the Enzyme Linked Immunoelectro Transfer Blot (EITB) was used. Sera from infected patients with T.solium, H.nana, and E.granulosus were assessed against crude, ammonium sulphate precipitated (TSASP), and lentil-lectin purified antigens of T.solium and crude antigens of.H.nana and E.granulosus. Several bands, recognized by sera from patients with T.solium, H.nana, and E.granulosus infections, were common to either two or all three cestodes. Unique reactive bands in H.nana were noted at 49 and 66 K-Da and in E.granulosus at 17-21 K-Da and at 27-32 K-Da. In the crude cysticercosis extract, a specific non glycoprotein band was present at 61-67 K-Da in addiction to specific glycoprotein bands of 50, 42, 24, 21, 18, 14, and 13 K-Da. None of the sera from patients with H.nana or E.granulosus infection cross reacted with these seven glycoprotein bands considered specific for T.solium infection.<br>Soros de pacientes infectados com Taenia solium, Hymenolepis nana e Echinococcus granulosus foram testados contra antígenos parasitários homólogos e heterólogos usando o teste de ELISA e foi verificado alto grau de reatividade cruzada. Para identificar os polipetídeos responsáveis por esta reatividade cruzada foi utilizado o teste "Enzyme Linked Immunoelectro Transfer Blot (EITB)". Soros de pacientes infectados por T.solium, H.nana, e E.granulosus foram colocados em contato com precipitado de sulfato de amônia e antígenos não purificados de T.solium e os de H.nana e E.granulosus. Várias bandas reconhecidas pelos soros de pacientes com infecção por T.solium, H.nana e E.granulosus foram comuns a dois ou três destes cestódeos. Uma única banda foi notada em H.nana a 49 e 66K-Da e no E.granulosus a 17-21 K-Da e 27-32 K-Da. No extrato não purificado de cisticercose uma banda específica não glicoproteica estava presente a 61-67 K-Da além das bandas de glicoproteínas específicas de 50, 42, 24, 21, 18, 14 e 13 K-Da. Nenhum destes soros de pacientes com infecção por H.nana ou E.granulosus reagiu de forma cruzada com estas sete bandas de glicoproteína consideradas específicas à infecção por T.soliu

    Multifactorial diversity sustains microbial community stability

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    Item does not contain fulltextMaintenance of a high degree of biodiversity in homogeneous environments is poorly understood. A complex cheese starter culture with a long history of use was characterized as a model system to study simple microbial communities. Eight distinct genetic lineages were identified, encompassing two species: Lactococcus lactis and Leuconostoc mesenteroides. The genetic lineages were found to be collections of strains with variable plasmid content and phage sensitivities. Kill-the-winner hypothesis explaining the suppression of the fittest strains by density-dependent phage predation was operational at the strain level. This prevents the eradication of entire genetic lineages from the community during propagation regimes (back-slopping), stabilizing the genetic heterogeneity in the starter culture against environmental uncertainty

    Anatomical terminology of the internal nose and paranasal sinuses: cross-cultural adaptation to Portuguese

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    Introduction: Functional endonasal endoscopic surgery is a frequent surgical procedure among otorhinolaryngologists. In 2014, the European Society of Rhinology published the “European Position Paper on the Anatomical Terminology of the Internal Nose and Paranasal Sinuses”, aiming to unify the terms in the English language. We do not yet have a unified terminology in the Portuguese language. Objective: Transcultural adaptation of the anatomical terms of the nose and paranasal cavities of the “European Anatomical Terminology of the Internal Nose and Paranasal Sinuses” to Portuguese. Methods: A group of rhinologists from diverse parts of Brazil, all experienced in endoscopic endonasal surgery, was invited to participate in the creation of this position paper on the anatomical terms of the nose and paranasal sinuses in the Portuguese language according to the methodology adapted from that previously described by Rudmik and Smith. Results: The results of this document were generated based on the agreement of the majority of the participants according to the most popular suggestions among the rhinologists. A cross-cultural adaptation of the sinonasal anatomical terminology was consolidated. We suggest the terms “inferior turbinate”, “nasal septum”, “(bone/cartilaginous) part of the nasal septum”, “(middle/inferior) nasal meatus”, “frontal sinus drainage pathway”, “frontal recess” and “uncinate process” be standardized. Conclusion: We have consolidated a Portuguese version of the European Anatomical Terminology of the Internal Nose and Paranasal Sinuses, which will help in the publication of technical announcements, scientific publications and the teaching of the internal anatomical terms of the nose and paranasal sinuses in Brazil. Resumo: Introdução: A cirurgia endoscópica funcional endonasal é um procedimento cirúrgico frequente entre os otorrinolaringologistas. Em 2014, a Sociedade Europeia de Rinologia publicou o “Documento Europeu para Posicionamento sobre a Terminologia Anatômica Interna do Nariz e das Cavidades Paranasais” com o objetivo de unificar os termos na língua inglesa. Ainda não dispomos de uma terminologia unificada na língua portuguesa. Objetivo: Adaptação transcultural dos termos anatômicos do nariz e das cavidades paranasais para o português da “European Anatomical Terminology of the Internal Nose and Paranasal Sinuses”. Método: Um grupo de rinologistas de todo o Brasil, com experiência em cirurgia endoscópica endonasal, foi convidado a participar da elaboração desse posicionamento sobre os termos anatômicos do nariz e das cavidades paranasais para o português conforme metodologia adaptada da previamente descrita por Rudmik e Smith. Resultados: Os resultados desse documento foram gerados a partir da concordância da maioria dos participantes conforme as sugestões mais populares entre os rinologistas. Uma adaptação transcultural da terminologia anatômica nasossinusal foi consolidada. Sugerimos que se busque uniformizar termos como “concha inferior”, “septo nasal”, “porção (óssea/cartilagionasa) do septo nasal”, “meato (médio/ inferior) nasal”, “via da drenagem do seio frontal”,“recesso frontal” e “processo uncinado”. Conclusão: Consolidamos uma versão adaptada em português da “European Anatomical Terminology of the Internal Nose and Paranasal Sinuses” que auxiliará a publicação de comunicados técnicos, publicações científicas e o ensino dos termos anatômicos internos do nariz e das cavidades paranasais no Brasil. Keywords: Cross-cultural adaptation, Anatomy, Nose, Paranasal sinus, Consensus, Palavras-chave: Adaptação transcultural, Anatomia, Nariz, Cavidades paranasais, Consens
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