191 research outputs found
Detectability of large correlation length inflationary magnetic field with Cherenkov telescopes
Magnetic fields occupying the voids of the large scale structure may be a
relic from the Early Universe originating from either Inflation or from
cosmological phase transitions. We explore the possibility of identifying the
inflationary origin of the void magnetic fields and measuring its parameters
with gamma-ray astronomy methods. The large correlation length inflationary
field is expected to impose a characteristic asymmetry of extended gamma-ray
emission that is correlated between different sources on the sky. We show that
a set of nearby blazars for which the extended emission is observable in the
0.1-1 TeV band with CTA can be used for the test of inflationary origin of the
void magnetic fields.Comment: 8 pages, 6 figures, accepted to JET
Constraint on intergalactic magnetic field from Fermi/LAT observations of the "pair echo" of GRB 221009A
Delayed "pair echo" signal from interactions of very-high-energy gamma rays
in the intergalactic medium can be used for detection of the inter-galactic
magnetic field (IGMF). We use the data of Fermi/LAT telescope coupled with
LHAASO observatory measurements to confirm the presence of IGMF along the line
of sight to the gamma-ray burst GRB221009A. Comparing the Fermi/LAT
measurements with the expected level of the pair echo flux, set by the
multi-TeV LHAASO detection, we derive a lower bound G on the IGMF
with correlation length larger than 1 Mpc, improving as for
shorter correlation lengths. This provides an independent verification of
existence of a lower bound on IGMF in the voids of the Large Scale Structure,
previously derived from the observations of active galactic nuclei.Comment: 4 pages, 2 figue
Scheduling problems for mobile cloud computing
Nowadays the popularity of mobile devices is rapidly increased.
New facilities of them (Wi-Fi, GPS, high speed processors etc.) allows
to improve mobile applications in commerce, learning, gaming, health
monitoring, sports etc. But really there are several reasons that limit
mobile computing: limited storage capacity, limited battery life and
limited processing power of mobile devices.
This paper is dedicated to Mobile cloud computing (MCC). We
consider MCC as combination of mobile and cloud computing where
both data storage and data processing are performed outside the mobile
device but inside the cloud
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Immunohistochemical Studies of S-100 Protein During Postnatal Ontogenesis of the Brain of Two Strains of Rats
We have studied the dynamics of the appearance of cells reacting positively with anti-S-100 protein antiserum, during postnatal neurocytogenesis in the brain of rats of two strains differing in their susceptibility to sound stimuli. The postnatal time of appearance of cells reacting positively with anti-S-100 protein antiserum was somewhat later in rats susceptible to sound-induced seizures than in sound-resistant rats. These differences concerned mainly the cerebral cortex of 12-day-old rats. By day 21 of postnatal life these differences had disappeared. In subcortical structures of the brain, S-100 protein was first found on the 4th to the 5th day of life and the rate of appearance of cells containing this protein was similar in the two strains
Optical properties of colloidal solutions of metal nanoparticles
nanoparticles, spectroscopy, light absorption, plasmon, plasmon resonanceNanoparticles are finding more practical applications in various fields of human activity, including veterinary and medicine. Due to the fact that the effectiveness of colloidal solutions of nanoparticles is directly related to their aggregate state, convenient methods for assessing the physicochemical characteristics of such preparations is of high priority. Nanoparticles have unique optical properties that depend on their size and shape. They can be determined by the refractive index of light on the surface of nanoparticles in a phenomenon known as plasmon resonance, which makes the UV-Vis spectroscopy a valuable tool for studying and evaluating the properties of nanomaterials. Optical characteristics of NPs colloidal solutions of noble metals (silver) or bioelements (copper, silicon dioxide) were determined at various wavelengths (nm): 300–800 nm. The surface plasmon resonance has been found in all test preparations, while all of them exhibited obvious nonlinear optical properties. The most pronounced plasmon resonance peak was found in the colloidal solution of silver NPs within a wavelength of 420 nm. In the case of a colloidal solution of copper NPs, the peak of plasmon resonance was less pronounced and had a red shift (peak at 560 nm). In the colloidal solution of silicon dioxide, the plasmon resonance was less pronounced than in other test preparations, being shifted to the blue side of the spectrum (360 nm). UV-Vis spectroscopy of metal NPs requires further studies to assess their stability and influence of various external factors on their activity
Results of the Application of the Original Method of Surgical Treatment of Patients with Severe Hallux Valgus
Background. Traditional methods of surgical treatment of severe Hallux valgus (HV) lead to a large number of complications and poor results. In order to avoid complications and improve the quality of treatment, an original technique of double osteotomy of the first metatarsal bone has been proposed.The aim of the study was to conduct a comparative assessment of the results of applying the original technique in the treatment of patients with severe Hallux valgus.Materials and methods. A retrospective analysis of the treatment of 95 patients operated on at the Seversk Clinical Hospital for severe Hallux valgus in the period from 2008 to 2016 was performed. The study group included 60 patients who underwent surgery according to the original method. In a comparison group of 35 people, Logroshino's surgery was performed. Clinical, radiological, surgical and statistical research methods were used.Results. The final assessment of the results 1 year after the operation showed an unacceptably high number of Hallux valgus relapses, complications, and unsatisfactory results in the comparison group. The use of original approachesfor osteotomy of the first metatarsal bone in patients of the study group allowed to significantly improve treatment results and achieve good results in 85 % of cases.Conclusion. The proposed surgical technique is effective and shows statistically significantly better results 1 year after surgery. Application of the original technique will improve the results of surgical correction of the severe degree of Hallux valgus, which consists in reducing the number of complications and improving functional indicators
Stem Cells and Neuroprotection: Understanding the Players
The use of neuroprotective therapies begs the question of how such therapies could affect preexisting stem cell populations within the host, as well as those introduced through cell-replacement therapy. Multiple mechanisms may mediate stem cell responses to neuroprotectants such as host/donor age and gender, cellular lineage/differentiation status, and mitochondrial dynamics. Current therapeutic sources for stem cells are embryonic, somatic, or induced pluripotent, with very little known about the effects of gender, age, cell type, and mitochondrial dynamics. With the advent of therapies to stimulate and recruit endogenous stem cells or transplant donor cells into damage areas in the hopes of recuperative regeneration of lost neurons, it is important to discuss mechanisms that dictate the winning players in the neuroprotection game. This review will focus on our current understanding of the characteristics of renewing stem cells that may affect neuroprotection
The Large High Altitude Air Shower Observatory (LHAASO) Science White Paper
The Large High Altitude Air Shower Observatory (LHAASO) project is a new
generation multi-component instrument, to be built at 4410 meters of altitude
in the Sichuan province of China, with the aim to study with unprecedented
sensitivity the spec trum, the composition and the anisotropy of cosmic rays in
the energy range between 10 and 10 eV, as well as to act
simultaneously as a wide aperture (one stereoradiant), continuously-operated
gamma ray telescope in the energy range between 10 and eV. The
experiment will be able of continuously surveying the TeV sky for steady and
transient sources from 100 GeV to 1 PeV, t hus opening for the first time the
100-1000 TeV range to the direct observations of the high energy cosmic ray
sources. In addition, the different observables (electronic, muonic and
Cherenkov/fluorescence components) that will be measured in LHAASO will allow
to investigate origin, acceleration and propagation of the radiation through a
measurement of energy spec trum, elemental composition and anisotropy with
unprecedented resolution. The remarkable sensitivity of LHAASO in cosmic rays
physics and gamma astronomy would play a key-role in the comprehensive general
program to explore the High Energy Universe. LHAASO will allow important
studies of fundamental physics (such as indirect dark matter search, Lorentz
invariance violation, quantum gravity) and solar and heliospheric physics. In
this document we introduce the concept of LHAASO and the main science goals,
providing an overview of the project.Comment: This document is a collaborative effort, 185 pages, 110 figure
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