165 research outputs found

    Criticality in confined ionic fluids

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    A theory of a confined two dimensional electrolyte is presented. The positive and negative ions, interacting by a 1/r1/r potential, are constrained to move on an interface separating two solvents with dielectric constants ϵ1\epsilon_1 and ϵ2\epsilon_2. It is shown that the Debye-H\"uckel type of theory predicts that the this 2d Coulomb fluid should undergo a phase separation into a coexisting liquid (high density) and gas (low density) phases. We argue, however, that the formation of polymer-like chains of alternating positive and negative ions can prevent this phase transition from taking place.Comment: RevTex, no figures, in press Phys. Rev.

    Benefits of homemade chocolate consumption on human health

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    Objective: To describe the benefits of homemade chocolate consumption on human health in La Chontalpa, Tabasco, Mexico. Design/Methodology/Approach: We interviewed 49 persons in La Chontalpa, along with 30 contacts from social networks; additionally, a participatory workshop was held with 15 persons trained in making homemade chocolate. A traditional specialist doctor who uses cacao as a medicinal base was interviewed and we were observers during cacao ceremonies. The information was analyzed using opinion analysis and the Chi-square test. Results: Ninety-seven-point nine percent of the interviewees agreed that consuming homemade chocolate is beneficial for health, while 89.8% mentioned that consuming chocolate makes them feel good. Fifty-five percent of the consumers consider that chocolate provides them energy; 51.1% say that it helps them to control hunger and thirst; and 36.7% feel that consuming it takes away sadness and laziness. The benefits of chocolate consumption reported in the ceremonies, workshops, and interviews were that it controls depression, promotes concentration, and causes joy; it also cures diarrhea, anemia, headaches, and stomach ache. Study Limitations/Implications: The sanitary restrictions derived from the COVID-19 pandemic limited face-to-face interviews in 2021, which were instead carried out using social networks. It is forbidden to record and take photos and videos of cacao ceremonies; therefore, we were unable to document them. Findings/Conclusions: In La Chontalpa, Tabasco, the population consumes homemade chocolate because they believe that chocolate provides mental and physical health benefits

    Measurement of the Bottom-Strange Meson Mixing Phase in the Full CDF Data Set

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    We report a measurement of the bottom-strange meson mixing phase \beta_s using the time evolution of B0_s -> J/\psi (->\mu+\mu-) \phi (-> K+ K-) decays in which the quark-flavor content of the bottom-strange meson is identified at production. This measurement uses the full data set of proton-antiproton collisions at sqrt(s)= 1.96 TeV collected by the Collider Detector experiment at the Fermilab Tevatron, corresponding to 9.6 fb-1 of integrated luminosity. We report confidence regions in the two-dimensional space of \beta_s and the B0_s decay-width difference \Delta\Gamma_s, and measure \beta_s in [-\pi/2, -1.51] U [-0.06, 0.30] U [1.26, \pi/2] at the 68% confidence level, in agreement with the standard model expectation. Assuming the standard model value of \beta_s, we also determine \Delta\Gamma_s = 0.068 +- 0.026 (stat) +- 0.009 (syst) ps-1 and the mean B0_s lifetime, \tau_s = 1.528 +- 0.019 (stat) +- 0.009 (syst) ps, which are consistent and competitive with determinations by other experiments.Comment: 8 pages, 2 figures, Phys. Rev. Lett 109, 171802 (2012

    Horizontal muon track identification with neural networks in HAWC

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    Nowadays the implementation of artificial neural networks in high-energyphysics has obtained excellent results on improving signal detection. In thiswork we propose to use neural networks (NNs) for event discrimination in HAWC.This observatory is a water Cherenkov gamma-ray detector that in recent yearshas implemented algorithms to identify horizontal muon tracks. However, thesealgorithms are not very efficient. In this work we describe the implementationof three NNs: two based on image classification and one based on objectdetection. Using these algorithms we obtain an increase in the number ofidentified tracks. The results of this study could be used in the future toimprove the performance of the Earth-skimming technique for the indirectmeasurement of neutrinos with HAWC.<br

    SPT Clusters with DES and HST Weak Lensing. I. Cluster Lensing and Bayesian Population Modeling of Multi-Wavelength Cluster Datasets

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    We present a Bayesian population modeling method to analyze the abundance of galaxy clusters identified by the South Pole Telescope (SPT) with a simultaneous mass calibration using weak gravitational lensing data from the Dark Energy Survey (DES) and the Hubble Space Telescope (HST). We discuss and validate the modeling choices with a particular focus on a robust, weak-lensing-based mass calibration using DES data. For the DES Year 3 data, we report a systematic uncertainty in weak-lensing mass calibration that increases from 1\% at z=0.25z=0.25 to 10\% at z=0.95z=0.95, to which we add 2\% in quadrature to account for uncertainties in the impact of baryonic effects. We implement an analysis pipeline that joins the cluster abundance likelihood with a multi-observable likelihood for the SZ, optical richness, and weak-lensing measurements for each individual cluster. We validate that our analysis pipeline can recover unbiased cosmological constraints by analyzing mocks that closely resemble the cluster sample extracted from the SPT-SZ, SPTpol~ECS, and SPTpol~500d surveys and the DES Year~3 and HST-39 weak-lensing datasets. This work represents a crucial prerequisite for the subsequent cosmological analysis of the real dataset.Comment: submitted to PR

    The High-Altitude Water Cherenkov (HAWC) Observatory in M\'exico: The Primary Detector

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    The High-Altitude Water Cherenkov (HAWC) observatory is a second-generation continuously operated, wide field-of-view, TeV gamma-ray observatory. The HAWC observatory and its analysis techniques build on experience of the Milagro experiment in using ground-based water Cherenkov detectors for gamma-ray astronomy. HAWC is located on the Sierra Negra volcano in M\'exico at an elevation of 4100 meters above sea level. The completed HAWC observatory principal detector (HAWC) consists of 300 closely spaced water Cherenkov detectors, each equipped with four photomultiplier tubes to provide timing and charge information to reconstruct the extensive air shower energy and arrival direction. The HAWC observatory has been optimized to observe transient and steady emission from sources of gamma rays within an energy range from several hundred GeV to several hundred TeV. However, most of the air showers detected are initiated by cosmic rays, allowing studies of cosmic rays also to be performed. This paper describes the characteristics of the HAWC main array and its hardware.Comment: Accepted for publications in Nuclear Inst. and Methods in Physics Research, A (2023) 168253 ( https://www.sciencedirect.com/science/article/abs/pii/S0168900223002437 ); 39 pages, 14 Figure

    A Contribution of the HAWC Observatory to the TeV era in the High Energy Gamma-Ray Astrophysics: The case of the TeV-Halos

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    We present a short overview of the TeV-Halos objects as a discovery and a relevant contribution of the High Altitude Water \v{C}erenkov (HAWC) observatory to TeV astrophysics. We discuss history, discovery, knowledge, and the next step through a new and more detailed analysis than the original study in 2017. TeV-Halos will contribute to resolving the problem of the local positron excess observed on the Earth. To clarify the latter, understanding the diffusion process is mandatory.Comment: Work presented in the 21st International Symposium on Very High Energy Cosmic Ray Interactions(ISVHECRI 2022) as part of the Ph. D. Thesis of Ramiro Torres-Escobedo (SJTU, Shanghai, China). Accepted for publication in SciPost Physics Proceedings (ISSN 2666-4003). 11 pages, 3 Figures. Short overview of HAWC and TeV Halos objects until 202

    A Mitosis Block Links Active Cell Cycle with Human Epidermal Differentiation and Results in Endoreplication

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    How human self-renewal tissues co-ordinate proliferation with differentiation is unclear. Human epidermis undergoes continuous cell growth and differentiation and is permanently exposed to mutagenic hazard. Keratinocytes are thought to arrest cell growth and cell cycle prior to terminal differentiation. However, a growing body of evidence does not satisfy this model. For instance, it does not explain how skin maintains tissue structure in hyperproliferative benign lesions. We have developed and applied novel cell cycle techniques to human skin in situ and determined the dynamics of key cell cycle regulators of DNA replication or mitosis, such as cyclins E, A and B, or members of the anaphase promoting complex pathway: cdc14A, Ndc80/Hec1 and Aurora kinase B. The results show that actively cycling keratinocytes initiate terminal differentiation, arrest in mitosis, continue DNA replication in a special G2/M state, and become polyploid by mitotic slippage. They unambiguously demonstrate that cell cycle progression coexists with terminal differentiation, thus explaining how differentiating cells increase in size. Epidermal differentiating cells arrest in mitosis and a genotoxic-induced mitosis block rapidly pushes epidermal basal cells into differentiation and polyploidy. These observations unravel a novel mitosis-differentiation link that provides new insight into skin homeostasis and cancer. It might constitute a self-defence mechanism against oncogenic alterations such as Myc deregulation

    Implantación de un registro específico de reacciones adversas a ferroterapia endovenosa ambulatoria en un hospital de tercer nivel

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    Poster [PC-118] Introducción: La Agencia Española de medicamentos y productos sanitarios (AEMPS) estableció en 2013 nuevas recomendaciones para la administración intravenosa de preparados de hierro tras la notificación de reacciones de hipersensibilidad. Aunque estos preparados mantienen un balance beneficio-riesgo favorable se deben establecer medidas específicas para la identificación temprana y el tratamiento inmediato de las reacciones alérgicas. Pacientes y Métodos: Implantación de medidas de seguridad en la vigilancia de la administración intravenosa de preparados de hierro cumpliendo los tiempos de observación recomendados por la AEMPS. Elaboración de un formulario de reacciones adversas específico para la administración de ferroterapia endovenosa, de fácil cumplimentación por el personal de Enfermería del hospital de Día de Hematología del Hospital Universitario Miguel Servet. Análisis de la incidencia de reacciones adversas en relación con la ferroterapia prescrita desde la consulta de Eritropatología a pacientes con anemia ferropénica. Estudio descriptivo y prospectivo realizado en un periodo de 4 meses (Enero 2018 – Mayo 2018). Análisis de las reacciones adversas detectadas en relación al tratamiento con hierro endovenoso disponible en nuestro centro en diferentes posologías: hierro-sacarosa (Venofer®) 200 mg, hierro-carboximaltosa (Ferinject®) 500 mg y 1 gr. Resultados: Se han estudiado 77 pacientes. 52 hombres y 25 mujeres. La mediana de edad fue 68 años. 21 (27, 27%) pacientes tenían alergias o intolerancias conocidas previamente. 53 (68, 83%) recibieron tratamiento con hierro sacarosa (200mg) y 24 (31, 17%) con hierro carboximaltosa [20 (83, 83%) 500mg, 4 (16, 67%) 1g]. Todos los pacientes cumplieron los tiempos de vigilancia recomendados por la AEMPS. Únicamente dos pacientes presentaron reacciones adversas al hierro y ambos con dosis de 200mg de hierro sacarosa. Los dos presentaron reacciones gastrointestinales leves de duración autolimitada de unos 15 minutos, sin repercusión orgánica y sin precisar medicación para su resolución. Conclusiones: Las reacciones graves de hipersensibilidad al hierro endovenoso son, como en nuestra serie de casos, efectos adversos muy poco frecuentes. A diferencia de los casos descritos de reacciones graves anafilácticas, en nuestro centro no hemos detectado ninguna gravedad en todos los tratamientos administrados. Tampoco hemos podido relacionar las dos reacciones leves detectadas con predisposición previa de los pacientes al desarrollo de alergias medicamentosas u otras intolerancias, ni tampoco con la dosis de hierro o preparado administrado. Dada la alerta de la AEMPS, nuestro registro específico de reacciones adversas a ferroterapia endovenosa nos permite estar alerta y constatar de manera objetiva la existencia o no de dichas reacciones así como su gravedad

    Choice of the initial antiretroviral treatment for HIV-positive individuals in the era of integrase inhibitors

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    BACKGROUND: We aimed to describe the most frequently prescribed initial antiretroviral therapy (ART) regimens in recent years in HIV-positive persons in the Cohort of the Spanish HIV/AIDS Research Network (CoRIS) and to investigate factors associated with the choice of each regimen. METHODS: We analyzed initial ART regimens prescribed in adults participating in CoRIS from 2014 to 2017. Only regimens prescribed in >5% of patients were considered. We used multivariable multinomial regression to estimate Relative Risk Ratios (RRRs) for the association between sociodemographic and clinical characteristics and the choice of the initial regimen. RESULTS: Among 2874 participants, abacavir(ABC)/lamivudine(3TC)/dolutegavir(DTG) was the most frequently prescribed regimen (32.1%), followed by tenofovir disoproxil fumarate (TDF)/emtricitabine (FTC)/elvitegravir(EVG)/cobicistat(COBI) (14.9%), TDF/FTC/rilpivirine (RPV) (14.0%), tenofovir alafenamide (TAF)/FTC/EVG/COBI (13.7%), TDF/FTC+DTG (10.0%), TDF/FTC+darunavir/ritonavir or darunavir/cobicistat (bDRV) (9.8%) and TDF/FTC+raltegravir (RAL) (5.6%). Compared with ABC/3TC/DTG, starting TDF/FTC/RPV was less likely in patients with CD4100.000 copies/mL. TDF/FTC+DTG was more frequent in those with CD4100.000 copies/mL. TDF/FTC+RAL and TDF/FTC+bDRV were also more frequent among patients with CD4<200 cells//muL and with transmission categories other than men who have sex with men. Compared with ABC/3TC/DTG, the prescription of other initial ART regimens decreased from 2014-2015 to 2016-2017 with the exception of TDF/FTC+DTG. Differences in the choice of the initial ART regimen were observed by hospitals' location. CONCLUSIONS: The choice of initial ART regimens is consistent with Spanish guidelines' recommendations, but is also clearly influenced by physician's perception based on patient's clinical and sociodemographic variables and by the prescribing hospital location
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