3,344 research outputs found

    Supernova neutrino detection in Borexino

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    In this paper, the performances of Borexino as a Supernova neutrino detector are analyzed and discussed. The expected neutrino signal from a typical Type II Supernova at a distance of 10 kpc is calculated: a burst of around 240 events would appear in Borexino within a time interval of about 10 s. Most of these events would come from the reaction channels ¯νe + p → e+ + n and ν + p → ν + p, while about 30 events would be induced by the interaction of the Supernova neutrino flux on 12C in the liquid scintillator: for most of these reactions, Borexino features unique detection capabilities, thanks to its low-energy sensitivity, ultra-low radioactive background and large homogeneous volume. The possibility to tag and identify the different neutrino detection reactions gives access to key information concerning Supernova physics and non-standard neutrino properties. The detection of neutrinos via elastic scattering off protons in Borexino is discussed here for the first time: this reaction is proven to be a powerful component of the neutrino-induced burst of events. Finally, a viable “Supernova trigger” condition is established, which allows to detect a Supernova explosion up to a distance of 63 kpc

    Effect of strain in the proximal ligand on the binding of nitric oxide and carbon monoxide to chelated protoheme complexes

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    The binding of NO and CO to chelated protoheme-L-histidine methyl ester (HM-H), protoheme-glycyl-L-histidine methyl ester (HM-GH), and free protoheme (HM) has been studied in methanol-DMSO solution. In all cases, the NO adducts are five-coordinated indicating that binding of NO occurs with displacement of the axial base and confirms the strong negative trans effect exerted by NO in heme complexes, though it is found that the presence of strain in the iron-histidine bond of HM-H has a positive influence on NO binding, making it thermodynamically more favorable than for HM-GH. The equilibrium constants thus decrease in the series HM>HM-H>HM-GH. In contrast to NO, CO has a positive trans effect, and therefore, an opposite trend is observed in the binding of this ligand to the heme complexe

    New Measurement of the Relative Scintillation Efficiency of Xenon Nuclear Recoils Below 10 keV

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    Liquid xenon is an important detection medium in direct dark matter experiments, which search for low-energy nuclear recoils produced by the elastic scattering of WIMPs with quarks. The two existing measurements of the relative scintillation efficiency of nuclear recoils below 20 keV lead to inconsistent extrapolations at lower energies. This results in a different energy scale and thus sensitivity reach of liquid xenon dark matter detectors. We report a new measurement of the relative scintillation efficiency below 10 keV performed with a liquid xenon scintillation detector, optimized for maximum light collection. Greater than 95% of the interior surface of this detector was instrumented with photomultiplier tubes, giving a scintillation yield of 19.6 photoelectrons/keV electron equivalent for 122 keV gamma rays. We find that the relative scintillation efficiency for nuclear recoils of 5 keV is 0.14, staying constant around this value up to 10 keV. For higher energy recoils we measure a value around 20%, consistent with previously reported data. In light of this new measurement, the XENON10 experiment's results on spin-independent WIMP-nucleon cross section, which were calculated assuming a constant 0.19 relative scintillation efficiency, change from 8.8×10448.8\times10^{-44} cm2^2 to 9.9×10449.9\times10^{-44} cm2^2 for WIMPs of mass 100 GeV/c2^2, and from 4.4×10444.4\times10^{-44} cm2^2 to 5.6×10445.6\times10^{-44} cm2^2 for WIMPs of mass 30 GeV/c2^2.Comment: 8 pages, 8 figure

    The situational version of the brief COPE: Dimensionality and relationships with goal-related variables

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    This study is aimed at investigating the dimensionality of the situational version of the Brief COPE, a questionnaire that is frequently used to assess a broad range of coping responses to specific difficulties, by comparing five different factor models highlighted in previous studies. It also aimed at exploring the relationships among coping responses, personal goal commitment and progress. The study involved 606 adults (male = 289) ranging in age from 19 to 71. Using confirmatory factor analysis, we compared five models and assessed relationships of coping responses with goal commitment and progress. The results confirmed the theoretical factor structure of the situational Brief COPE. All the 14 dimensions showed acceptable reliability and relationships with goal commitment and progress, attesting the reliability and usefulness of this measure to evaluate coping responses to specific events

    Monitoring of Communication Precursors in Extremely Low Birth Weight (ELBW) Newborns by Video Analysis Method: Preliminary Results

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    Background: The survival of extremely low birth weight infants (ELBW) has increased worldwide. Even in the absence of major disabilities, ELBW infants show difficulty in simple language functions. It is relevant to assess early abilities, which are the base of early linguistic skills, in order to implement customized intervention programs in ELBW infants. Aims: To evaluate communication precursors of language development in ELBW infants at 12 and 24 months of correct age (C.A). To investigate the correlation of linguistic and communicative prerequisites with mental development outcome at 24 months CA. Method: 52 ELBW neonates (mean gestational age 26.6 weeks, mean birth weight was 775 g) who were admitted to the neonatal intensive care unit of the University Hospital of Modena, were enrolled. Data were collected from archived audio-video recordings of neurodevelopmental follow-up visits. Video analysis of communicative and linguistic developmental was performed at 12 and 24 months CA. Neurodevelopmental outcome was evaluated with Mental Developmental Scales (GMDS-R). Results: The video-analysis showed that infants at 12 months CA used predominantly eye contacts and gestural turns, while vocal turns were scant. At 24 months CA, a significant change in eye contacts, vocal turns, gestural turns, and utterances (p < 0.001) occurred. The total number of utterances (p = 0.036) and eye contacts (p = 0.045) were significantly correlated to the Development Quotient (DQ) of Hearing and Language scale. Moreover, a significant correlation was found with the Personal-Social scale vocal turns (p = 0.009) and the total number of utterances (p = 0,02). Finally, the Global Quotient of the GMDS-R was related to the Vocal Turns (p = 0.034) and the total number of Utterances (p = 0.013). Conclusions: ELBW infants at 12 months CA use predominantly eye contacts and gestural turns to communicate with adults. At 24 months CA, the child’s communicative intention evolves from gestural to verbal communication. The latter is characterized by an increase in both vocal turns and the number of utterances produced during interaction. The video analysis we implement appears to be a sensitive tool for early assessment of communication and language development and to refine early intervention

    Outcome at 2-year of treatment in first-episode psychosis patients who were enrolled in a specialized early intervention program

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    Treatment in early intervention services (EIS) seems superior to treatment as usual on several outcomes, but the extent of heterogeneity in response is unclear. In this study, treatment response trajectories up to 2 years in first-episode psychosis (FEP) patients enrolled in an Italian early intervention service (EIS) have been quantified. The 24-item Brief Psychiatric Rating Scale (BPRS) was used to quantify treatment response up to 2 years in 129 participants. Conditional growth modeling and latent class growth analysis were used to test changes over time in the BPRS and separation into independent classes over time. Group differences were tested on socio-demographic and clinical variables known to be related to outcome in psychosis. Scores on the BPRS showed a statistically significant decrease in overall scores across all tested models. Four trajectories were identified across 2 years. Most patients showed a progressive decrease in the BPRS scores; a scant fraction showed a more stepped decrease from very high levels of psychopathology. No potential predictor was statistically related to the time course of BPRS scores. Most patients that undergo treatment within an EIS are characterized by amelioration, but patients that have higher baseline scores of psychopathology require more intensive treatment

    Importance of Sexual Function Assessment in Multidimensional Evaluation of AGHD Patients: Results from the MAGHD Study.

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    Background: Adult growth hormone deficiency (AGHD) is a debilitating clinical condition leading to decreased quality of life (QoL). The impact of reduced muscle mass, weakening and loss of vitality on QoL have been well characterized in AGHD. The impact of AGHD on sexual function, a recognized factor able to modify well-being, has never been investigated. Aim: To investigate the prevalence of sexual dysfunction in AGHD patients referring to a single endocrinological center and grouped according to their his- tory of r-hGH therapy.Methods: The Management of Adult Growth Hormone Deficiency (MAGHD) Study is a pro- spective, real-life trial aiming to improve management of AGHD patients through a smartphone app (MAGHD App)and a wearable device. The 83 AGHD enrolled patients (31 Females, 52 Males, mean age 56.27 + 14.68 years) were divided in 3 groups (G) according to r-hGH therapy: on long-term r-hGH therapy (G1, n=32), previously treated with r-hGH (G2, n=20), never treated (G3, n=31). Within the first phase of the study, a large database was created collecting clinical, biochemical and psychological data. In addition to QLS-H and QoL-AGHDA routinely used to as- sess QoL, IIEF-15 and FSFI were employed to evaluate sexual function in males and females, respectively. The nonparametric Kruskal-Wallis test was used for compar- ison among 3 groups.Results: Here only baseline data of the MAGHD Study are presented.According to IIEF-15 results, the prevalence of erectile dysfunction (ED) in male AGHD cohort was 60%. Erectile function (EF) score was signifi- cantly higher in G1 compared to both G2 and G3 (p < 0.05) with an ED prevalence of 35% in G1, 75% in G2 and 75% in G3. Even excluding patients with serum testosterone lower than 2 ng/ml and older than 65 years, ED prevalence did not change significantly in the 3 groups. Moreover, EF do- main was inversely and directly correlated to age (R20.130, β-0.360) and IGF1 levels (R20.156, β0.395), respectively. The prevalence of female sexual dysfunction according to FSFI was 89.3%. Even though desire, arousal, lubrication and overall scores were significantly higher (better results) in G1 compared to G2 and G3 (p < 0.05), no correlation resulted between FSFI domains and IGF1 levels. Instead an inverse correlation resulted between desire domain and age.Conclusions: This study, performed in a real-life clinical setting, demonstrates a high prevalence of sexual dysfunc- tion in AGHD patients and that r-hGH treatment seems to be associated to better sexual outcomes. These results suggest that the evaluation of sexual function should be in- tegrated in the global assessment of AGHD patients since sexual activity is a fundamental domain able to influence both well-being and QoL

    Low-Energy Electron-Track Imaging for a Liquid Argon Time-Projection-Chamber Telescope Concept using Probabilistic Deep Learning

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    The GammaTPC is an MeV-scale single-phase liquid argon time-projection-chamber gamma-ray telescope concept with a novel dual-scale pixel-based charge-readout system. It promises to enable a significant improvement in sensitivity to MeV-scale gamma-rays over previous telescopes. The novel pixel-based charge readout allows for imaging of the tracks of electrons scattered by Compton interactions of incident gamma-rays. The two primary contributors to the accuracy of a Compton telescope in reconstructing an incident gamma-ray's original direction are its energy and position resolution. In this work, we focus on using deep learning to optimize the reconstruction of the initial position and direction of electrons scattered in Compton interactions, including using probabilistic models to estimate predictive uncertainty. We show that the deep learning models are able to predict locations of Compton scatters of MeV-scale gamma-rays from simulated pixel-based data to better than 0.6 mm RMS error, and are sensitive to the initial direction of the scattered electron. We compare and contrast different deep learning uncertainty estimation algorithms for reconstruction applications. Additionally, we show that event-by-event estimates of the uncertainty of the locations of the Compton scatters can be used to select those events that were reconstructed most accurately, leading to improvement in locating the origin of gamma-ray sources on the sky
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