The origin of Galactic cosmic rays is a century-long puzzle. Indirect evidence points to their acceleration by supernova Shockwaves, but we know little of their escape from the shock and their ...evolution through the turbulent medium surrounding massive stars. Gamma rays can probe their spreading through the ambient gas and radiation fields. The Fermi Large Area Telescope (LAT) has observed the star-forming region of Cygnus X. The 1-to 100-gigaelectronvolt images reveal a 50-parsec-wide cocoon of freshly accelerated cosmic rays that flood the cavities carved by the stellar winds and ionization fronts from young stellar clusters. It provides an example to study the youth of cosmic rays in a superbubble environment before they merge into the older Galactic population.
Moon and quiet Sun detection with Fermi-LAT observatory Brigida, M.
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
02/2011, Letnik:
630, Številka:
1
Journal Article
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The Fermi gamma-ray space telescope is an international mission supporting two science instruments, the Gamma-Ray Burst Monitor (GBM), covering the energy range from few keV to 30
MeV, and the Large ...Area Telescope (LAT), a pair-conversion detector operating at energies from 30
MeV to 300
GeV. The Fermi telescope was successfully launched on June 11, 2008 and has been surveying the sky in gamma rays since August 2008. During the first months of the mission, Fermi has detected high-energy gamma rays from the Moon and quiet Sun since the first weeks of data taking. This emission is produced by interactions of cosmic rays; by nucleons with the solar and lunar surface (albedo), and electrons with solar photons in the heliosphere. The heliospheric emission is produced by inverse-Compton scattering and is predicted to be extended. Both Moon and the quiet Sun was detected by EGRET on CGRO with low statistics, but Fermi is the only gamma-ray mission capable of detecting the Moon and the quiet Sun and monitoring it over the full 24th solar cycle.
Here we present the analysis relative to the first months including the observation of the Moon and the Sun, the spectral analysis, the fluxes measurements and finally a comparison with models and previous detections.
Abstract Background The SARS-CoV-2 virus activates maternal and placental immune responses. Such activation in the setting of other infections during pregnancy is known to impact fetal brain ...development. The effects of maternal immune activation on neurodevelopment are mediated at least in part by fetal brain microglia. However, microglia are inaccessible for direct analysis, and there are no validated non-invasive surrogate models to evaluate in utero microglial priming and function. We have previously demonstrated shared transcriptional programs between microglia and Hofbauer cells (HBCs, or fetal placental macrophages) in mouse models. Methods and results We assessed the impact of maternal SARS-CoV-2 on HBCs isolated from 24 term placentas ( N = 10 SARS-CoV-2 positive cases, 14 negative controls). Using single-cell RNA-sequencing, we demonstrated that HBC subpopulations exhibit distinct cellular programs, with specific subpopulations differentially impacted by SARS-CoV-2. Assessment of differentially expressed genes implied impaired phagocytosis, a key function of both HBCs and microglia, in some subclusters. Leveraging previously validated models of microglial synaptic pruning, we showed that HBCs isolated from placentas of SARS-CoV-2 positive pregnancies can be transdifferentiated into microglia-like cells (HBC-iMGs), with impaired synaptic pruning behavior compared to HBC models from negative controls. Conclusion These findings suggest that HBCs isolated at birth can be used to create personalized cellular models of offspring microglial programming.
Acute SARS-CoV-2 respiratory disease is an infectious respiratory disease caused by the virus SARS-CoV-2 belonging to the coronaviridae family. A pandemic is still present as of May 2020. In addition ...to causing pneumonia, SARS-CoV-2 may induce a direct damage to the heart, causing myocarditis, with significant impairment of cardiac contractility, and/or pericarditis. Elderly patients and those with cardiovascular risk factors, such as hypertension and diabetes mellitus, are at increased risk of heart complications from COVID-19. In this review, we focused on the correlation between COVID-19 infection and the high sensitivity troponin T and I, and their significance in the development of myocarditis. Data emerging from the studies so far conducted indicate that a high value of high-sensitivity troponin represents a negative prognostic indicator when associated with heart damage on an infectious-inflammatory basis (i.e. myopericarditis). We should identify a safe and clear diagnostic algorithm, possibly combining patient clinical history, troponin levels and cardiac ultrasound findings that could help us in the prediction of myopericarditis.
Acute alcohol intoxication is actually a common admission cause in the Emergency Department and represents an increasing public health burden, in particular among adolescents. It involves possible ...and significant illness and injury, which can quickly get worse and may need to be managed in the emergency room.
We conducted a narrative review of the literature regarding the effectiveness of first aid role of the Emergency Department setting.
This review included eighteen studies about alcohol intoxication management in the Emergency Department; most of all highlights the emerging phenomenon in Europe and around the world of acute alcohol intoxication management in first aid. The treatment of acute alcohol intoxication depends on general clinical conditions of the patient, vital signs, hemodynamic stability, cognitive state, alcohol-related complications, which are closely related to the blood alcohol concentration. At the same time, symptoms could be extremely variable due to individual differences in alcohol metabolism. In case of mild-moderate intoxication (blood alcohol concentration < 1 g/L), no drugs are necessary. In case of severe intoxication (blood alcohol concentration > 1 g/L), it is necessary to support with intravenous fluids, treat hypoglycemia, hypotension, hypothermia and electrolyte imbalance, administer complex B and C vitamins and accelerate alcohol elimination from blood with metadoxine. Unlike adults, adolescents are more exposed to the toxic effect of alcohol (because of their immature hepatic alcohol dehydrogenase activity), and then, acute alcohol-related complications are more frequent and dangerous in young people than in adult population. In many cases, patients affected by acute alcohol intoxication referring to an Emergency Department have mild-moderate transitory symptoms that do not require the use of drugs; they can benefit from a clinical observation, with a clinical course often completed within 24 hours with a favorable outcome. Clinical observation with vital signs control is necessary also to evaluate the possible development of the alcohol withdrawal syndrome (that involves a specific treatment) and to evaluate also possible pathological complications of the organism, above all acute liver damage.
Patients affected by acute alcohol intoxication are the best candidates to apply the rules of the Temporary Observation Unit in the Emergency Department, because of a clinical course often completed within 24 hours, a favorable outcome and without the need for hospitalization. In many cases, hospitalization could be not necessary, but the patient affected by Alcohol Use Disorder must be referred to an Alcohol Addiction Unit for the follow-up, to reduce the risk of alcohol relapse and complications related to alcohol abuse, and financial costs of hospitalization.
The aim of this work was to investigate the influence of sample preparation including variation in moisture content and particle size on the accuracy of near infrared (NIR) spectroscopy models ...developed to predict Klason lignin, total lignin, and holocellulose in wood. Seventy-five samples of sawdust obtained from a eucalyptus plantation were divided into aliquots and submitted to three different treatments: traditional (TRAD), large particle dried at room temperature (LPRT), and large particle oven-dried (LPOD). The influence of sample preparation method on models’ accuracy was compared by statistical analysis. Overall, grinding to a larger particle size and drying at room temperature (treatment LPRT) did not decrease the accuracy of the prediction models when compared to the TRAD sample preparation method. These findings were more evident for Klason lignin and holocellulose. This is relevant because resources used for sample preparation (i.e. grinding and drying) can be minimized, which is expected to reduce the costs associated with analysis of wood properties by NIR.
We show the latest results of Fermi-LAT observations of the quiescent Sun during the first 18 months of the mission. During this period the solar activity was at its minimum, hence the solar emission ...induced by cosmic rays was at its maximum. Two emission components are clearly distinguished: the point-like emission from the solar disk due to the cosmic-ray cascades in the solar atmosphere, and the extended emission due to inverse Compton scattering of cosmic ray electrons on solar photons in the heliosphere. We present the entire analysis, showing spectra and angular profiles of both components and discuss the comparison with models and future plans. Finally we report on Fermi Large Area Telescope (LAT) detection of the first solar flares and discussing the possible emission mechanisms.
'Green Hispanisms': An Overview Pastor, Brígida M.; Davies, Lloyd Hughes
Romance studies : a journal of the University of Wales,
01/2023, Letnik:
41, Številka:
1
Journal Article
The Silicon Transition Radiation Detector (SiTRD) combines the excellent space resolution of a silicon tracker with the particle identification capability of a conventional TRD. The detector consists ...of multiple modules, each composed by a radiator and a tracker plane, separated by a gap and immersed in a magnetic field. This layout allows the separation of the TR photons possibly produced by radiating particles from their trajectories. Provided that the separation in the tracker plane is larger than the granularity of the tracker, the SiTRD can identify radiating particles from non-radiating ones. Moreover, the small amount of material encountered by the particles along their path does not significantly affect the momentum reconstruction performance of the tracker. These features make the SiTRD an attractive option when designing the inner tracker of a collider experiment. We have studied a possible SiTRD layout for the inner tracker of a collider experiment at LHC. The detector parameters have been optimized taking into account the geometry constraints derived from an upgrade proposal of the ATLAS inner tracker. A Monte Carlo simulation has been also developed in which the detector performance has been investigated.
The disposal of industrial effluents containing cadmium and copper ions is a significant environmental concern. This study aims to address this issue by evaluating the adsorption capacity of ...adsorbents derived from residual biomass from second-generation ethanol production. The objective is to effectively remove cadmium and copper ions from aqueous solutions. The biochar utilized in the study was characterized as microporous and exhibited characteristic bands associated with carboxyls and hydroxyls. The pH
PZC
(point of zero charge) was determined to be 8.0. The kinetic study revealed that the PSO (pseudo-second-order) model provided the best fit, indicating that the adsorption rate depends on the amount of solute adsorbed onto the adsorbent's surface. In the equilibrium study, it was observed that adsorption occurred in a monolayer, as evidenced by the superior fit of the Langmuir model. Furthermore, the equilibrium experimental data for the bicomponent system was more accurately represented by the empirical models of Extended Freundlich and Modified Redlich-Peterson. These findings demonstrate the potential of biochar derived from the residue of second-generation ethanol production, a novel application, in effectively removing cadmium and copper ions from aqueous solutions.
