7,242 research outputs found
Atmospheric neutrino oscillations and tau neutrinos in ice
The main goal of the IceCube Deep Core Array is to search for neutrinos of
astrophysical origins. Atmospheric neutrinos are commonly considered as a
background for these searches. We show here that cascade measurements in the
Ice Cube Deep Core Array can provide strong evidence for tau neutrino
appearance in atmospheric neutrino oscillations. A careful study of these tau
neutrinos is crucial, since they constitute an irreducible background for
astrophysical neutrino detection.Comment: 5 pages, 3 figure
Atmospheric neutrinos in ice and measurement of neutrino oscillation parameters
The main goal of the IceCube Deep Core Array is to search for neutrinos of
astrophysical origins. Atmospheric neutrinos are commonly considered as a
background for these searches. We show that the very high statistics
atmospheric neutrino data can be used to obtain precise measurements of the
main oscillation parameters.Comment: expanded discussion of systematic uncertainties, 8 pages, 4 figure
Unidentified Galactic High-Energy Sources as Ancient Pulsar Wind Nebulae in the light of new high energy observations and the new code
In a Pulsar Wind Nebula (PWN), the lifetime of inverse Compton (IC) emitting
electrons exceeds the lifetime of its progenitor pulsar (as well as its
shell-type remnant), but it also exceeds the age of those that emit via
synchrotron radiation. Therefore, during its evolution, the PWN can remain
bright in IC so that its GeV-TeV gamma-ray flux remains high for timescales
much larger (for 10^5 - 10^6 yrs) than the pulsar lifetime and the X-ray PWN
lifetime. In this scenario, the magnetic field in the cavity induced by the
wind of the progenitor star plays a crucial role. This scenario is in line with
the discovery of several unidentified or "dark" sources in the TeV gamma-ray
band without X-ray counterparts; and it is also finding confirmation in the
recent discoveries at GeV gamma rays. Moreover, these consequences could be
also important for reinterpreting the detection of starburst galaxies in the
TeV gamma-ray band when considering a leptonic origin of the gamma-ray signal.
Both theoretical aspects and their observational proofs will be discussed, as
well as the first results of our new modeling code.Comment: Proceedings of the 5th International Symposium on High-Energy
Gamma-Ray Astronomy (Gamma2012
Immune system and COVID-19 by sex differences and age
In COVID-19 disease, are reported gender differences in relation to severity and death. The aim of this review is to highlight gender differences in the immune response to COVID-19. The included studies were identified using PubMed, until 30 October 2020. The search included the following keywords: SARS-CoV-2, COVID-19, gender, age, sex, and immune system. Literature described that females compared to males have greater inflammatory, antiviral, and humoral immune responses. In female, estrogen is a potential ally to alleviate SARS-COV-2 disease. In male, testosterone reduces vaccination response and depresses the cytokine response. In the older patients, and in particular, in female older patients, it has been reported a progressive functional decline in the immune systems. Differences by gender were reported in infection diseases, including SARS-CoV-2. These data should be confirmed by the other epidemiological studies
Distribution and genetic variability of Staphylinidae across a gradient of anthropogenically influenced insular landscapes
This paper describes the distribution and genetic variability of rove beetles (Coleoptera Staphylinidae) in anthropogenically influenced insular landscapes. The study was conducted in the Azores archipelago, characterized by high anthropogenic influence and landscape fragmentation. Collections were made in five islands, from eight habitats, along a gradient of anthropogenic influence. The species of Staphylinidae from the Azores collected for this study were widely distributed and showed low habitat fidelity. Rove beetle richness was associated with anthropogenic influence and habitat type, increasing from less to more anthropogenic impacted habitats. However, genetic diversity of profiled species (i.e. with three or more specimens per species/habitat) does not seem affected by anthropogenic influence in the different habitat types, isolation or landscape fragmentation. COI haplotypes were, as a rule, not exclusive to a given island or habitat. High level of genetic divergence and nucleotide saturation was found in closely related morphological designated species, demonstrating possible disparities between currently defined taxonomic units based on morphology and molecular phylogenies of Staphylinidae. This study found evidence of cryptic speciation in the Atheta fungi (Gravenhorst) species complex which had thus far remained undetected. Similar trends were found for Oligota parva Kraatz, Oxytelus sculptus Gravenhorst, Oligota pumilio Kiesenwetter. Previous studies with lower taxonomical resolution may have underestimated the biotic diversity reported in the Azores in comparison to other Macaronesian archipelagos.info:eu-repo/semantics/publishedVersio
Quantum fluctuations in thin superconducting wires of finite length
In one dimensional wires, fluctuations destroy superconducting long-range
order and stiffness at finite temperatures; in an infinite wire, quasi-long
range order and stiffness survive at zero temperature if the wire's
dimensionless admittance is large, . We analyze the
disappearance of this superconductor-insulator quantum phase transition in a
finite wire and its resurrection due to the wire's coupling to its environment
characterized through the dimensionless conductance . Integrating over phase
slips, we determine the flow of couplings and establish the -- phase
diagram.Comment: 4 pages, 2 figure
Dysphagia: What we know? a minireview
Dysphagia refers either to the difficulty someone may have with the initial phases of a swallow (usually described as oropharyngeal dysphagia, “OD”) or to the sensation that foods and or liquids are somehow being obstructed in their passage from the mouth to the stomach (usually described as “esophageal dysphagia”). In patients with no indication of a somatic disease or abnormality, psychiatric conditions must be considered as a possible cause of OD. Moreover, diagnosis and treatment of dysphagia are not standardized. There is no universal standard tool for screening or clinical assessment of OD. Education of health professionals on early diagnosis and improvement of therapeutic strategies are mainstays to allow maximal recovery potential in this population. Future studies, clinical trials, clinical evidence and clear guidelines are needed to manage this condition
Inactivation of a CRF-dependent amygdalofugal pathway reverses addiction-like behaviors in alcohol-dependent rats.
The activation of a neuronal ensemble in the central nucleus of the amygdala (CeA) during alcohol withdrawal has been hypothesized to induce high levels of alcohol drinking in dependent rats. In the present study we describe that the CeA neuronal ensemble that is activated by withdrawal from chronic alcohol exposure contains ~80% corticotropin-releasing factor (CRF) neurons and that the optogenetic inactivation of these CeA CRF+ neurons prevents recruitment of the neuronal ensemble, decreases the escalation of alcohol drinking, and decreases the intensity of somatic signs of withdrawal. Optogenetic dissection of the downstream neuronal pathways demonstrates that the reversal of addiction-like behaviors is observed after the inhibition of CeA CRF projections to the bed nucleus of the stria terminalis (BNST) and that inhibition of the CRFCeA-BNST pathway is mediated by inhibition of the CRF-CRF1 system and inhibition of BNST cell firing. These results suggest that the CRFCeA-BNST pathway could be targeted for the treatment of excessive drinking in alcohol use disorder
Practical Experiences of a Smart Livestock Location Monitoring System leveraging GNSS, LoRaWAN and Cloud Services.
Livestock farming is, in most cases in Europe, unsupervised, thus making it difficult to ensure adequate control of the position of the animals for the improvement of animal welfare. In addition, the geographical areas involved in livestock grazing usually have difficult access with harsh orography and lack of communications infrastructure, thus the need to provide a low-power livestock localization and monitoring system is of paramount importance, which is crucial not for a sustainable agriculture, but also for the protection of native breeds and meats thanks to their controlled supervision. In this context, this work presents an Internet of things (IoT)-based system integrating low-power wide area (LPWA) technology, cloud and virtualization services to provide real-time livestock location monitoring. Taking into account the constraints coming from the environment in terms of energy supply and network connectivity, our proposed system is based on a wearable device equipped with inertial sensors, Global Positioning System (GPS) receiver and LoRaWAN transceiver, which can provide a satisfactory compromise between performance, cost and energy consumption. At first, this article provides the state-of-the-art localization techniques and technologies applied to smart livestock. Then, we proceed to provide the hardware and firmware co-design to achieve very low energy consumption, thus providing a significant positive impact to the battery life. The proposed platform has been evaluated in a pilot test in the Northern part of Italy, evaluating different configurations in terms of sampling period, experimental duration and number of devices. The results are analyzed and discussed for packe delivery ratio, energy consumption, localization accuracy, battery discharge measurement and delay
Wilson-loop formalism for Reggeon exchange in soft high-energy scattering
We derive a nonperturbative expression for the non-vacuum,
qqbar-Reggeon-exchange contribution to the meson-meson elastic scattering
amplitude at high energy and low momentum transfer, in the framework of QCD.
Describing the mesons in terms of colourless qqbar dipoles, the problem is
reduced to the two-fermion-exchange contribution to the dipole-dipole
scattering amplitudes, which is expressed as a path integral, over the
trajectories of the exchanged fermions, of the expectation value of a certain
Wilson loop. We also show how the resulting expression can be reconstructed
from a corresponding quantity in the Euclidean theory, by means of analytic
continuation. Finally, we make contact with previous work on Reggeon exchange
in the gauge/gravity duality approach.Comment: A few misprints in the expressions for the relevant Wilson loops have
been corrected. 55 pages, 7 figure
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