750 research outputs found
Towards portable muography with small-area, gas-tight glass Resistive Plate Chambers
Imaging techniques that use atmospheric muons, collectively named under the
neologism "muography", have seen a tremendous growth in recent times, mainly
due to their diverse range of applications. The most well-known ones include
but are not limited to: volcanology, archaeology, civil engineering, nuclear
reactor monitoring, nuclear waste characterization, underground mapping, etc.
These methods are based on the attenuation or deviation of muons to image large
and/or dense objects where conventional techniques cannot work or their use
becomes challenging.
In this context, we have constructed a muography telescope based on "mini
glass-RPC planes" following a design similar to the glass-RPC detectors
developed by the CALICE Collaboration and used by the TOMUVOL experiment in the
context of volcano radiography, but with smaller active area (16 16
cm). The compact size makes it an attractive choice with respect to other
detectors previously employed for imaging on similar scales. An important
innovation in this design is that the detectors are sealed. This makes the
detector more portable and solves the usual safety and logistic issues for gas
detectors operated underground and/or inside small rooms. This paper provides
an overview on our guiding principles, the detector development and our
operational experiences. Drawing on the lessons learnt from the first
prototype, we also discuss our future direction for an improved second
prototype, focusing primarily on a recently adopted serigraphy technique for
the resistive coating of the glass plates.Comment: 8 pages, 7 figures, XV Workshop on Resistive Plate Chambers and
Related Detectors (RPC2020
Proton-He elastic scattering at low energies
We present new accurate measurements of the differential cross section
and the proton analyzing power for proton-He
elastic scattering at various energies. A supersonic gas jet target has been
employed to obtain these low energy cross section measurements. The
distributions have been measured at = 0.99, 1.59,
2.24, 3.11, and 4.02 MeV. Full angular distributions of have been
measured at = 1.60, 2.25, 3.13, and 4.05 MeV. This set of
high-precision data is compared to four-body variational calculations employing
realistic nucleon-nucleon (NN) and three-nucleon (3N) interactions. For the
unpolarized cross section the agreement between the theoretical calculation and
data is good when a potential is used. The comparison between the
calculated and measured proton analyzing powers reveals discrepancies of
approximately 50% at the maximum of each distribution. This is analogous to the
existing `` Puzzle'' known for the past 20 years in nucleon-deuteron
elastic scattering.Comment: 22 pages, 9 figures, to be published in Physical Review C, corrected
reference 4
Innovative Modernization Management of High-Tech and Knowledge-Intensive Industries of Russian Economy
In the article a new economic category “innovative modernization” reflecting system technical and technological and organizational and economic updating of high-tech and knowledge-intensive industries of economy of Russia is offered and proved. Authors opened the essence and the content of the concept “innovative modernization”, various versions of long-term forecasts of development of economy of Russia in relation to high-tech and knowledge-intensive industries are analyzed: the scenario of the catchingup development, the scenario of the opened national innovative system, the scenario of creation of the innovative environment, the scenario of local technological leadership. By results of the analysis the need of replacement of model of the catching-up development by model of the innovative modernization capable to provide competitive advantages and innovative break in the conditions of globalization is proved from the theoretical point of view. On this basis the methodical principles of implementation of innovative modernization, such as selectivity are formulated (as limitation of a range of coverage by innovative modernization of branches of economy); independence (as ability to rely in innovative modernization on the national forces and opportunities); complexity (interrelation of technical and technological and organizational and economic aspects of innovative modernization). The crucial role of high-tech and knowledge-intensive industries in innovative updating of all other branches of the domestic industry and implementation of strategy of innovative break in Russia is defined and proved. The interrelation and interconditionality of branches of the high-tech services and branches making the knowledge-intensive production which is for branches of services not only a material basis, but also the animator of growth of economy in general are shown on the example of branch of the aviation industry and branch of air transportation. In the conclusion of work methodological bases of management of innovative modernization of high-tech and knowledgeintensive industries of economy of Russia in their interrelation and interconditionality providing sequence and interrelation of scenario forecasting of development of the Russian social and economic system, strategic priorities, strategic and program and target planning, reproduction of resources, competitiveness of innovative production, technical and technological and institutional providing, and also an efficiency assessment are created. Within this methodology expediency of application of the scenario of local technological leadership is proved and the most acceptable option of strategic planning for realization of strategy of innovative modernization is defined
Merging Galaxies in the SDSS EDR
We present a new catalog of merging galaxies obtained through an automated
systematic search routine. The 1479 new pairs of merging galaxies were found in
approximately 462 sq deg of the Sloan Digital Sky Survey Early Data Release
(SDSS EDR; Stoughton et al. 2002) photometric data, and the pair catalog is
complete for galaxies in the magnitude range 16.0 <= g* <= 20.
The selection algorithm, implementing a variation on the original
Karachentsev (1972) criteria, proved to be very efficient and fast. Merging
galaxies were selected such that the inter-galaxy separations were less than
the sum of the component galaxies' radii.
We discuss the characteristics of the sample in terms of completeness, pair
separation, and the Holmberg effect. We also present an online atlas of images
for the SDSS EDR pairs obtained using the corrected frames from the SDSS EDR
database. The atlas images also include the relevant data for each pair member.
This catalog will be useful for conducting studies of the general
characteristics of merging galaxies, their environments, and their component
galaxies. The redshifts for a subset of the interacting and merging galaxies
and the distribution of angular sizes for these systems indicate the SDSS
provides a much deeper sample than almost any other wide-area catalog to date.Comment: 58 pages, which includes 15 figures and 6 tables. Figures 2, 8, 9,
10, 11, 13, and 14 are provided as JPEG files. For online atlas, see
http://home.fnal.gov/~sallam/MergePair/ . Accepted for publication in A
The explanation of unexpected temperature dependence of the muon catalysis in solid deuterium
It is shown that due to the smallness of the inelastic cross-section of the
-atoms scattering in the crystal lattice at sufficiently low temperatures
the -mesomolecules formation from the upper state of the hyperfine
structure starts earlier than the mesoatoms thermolization. It
explains an approximate constancy of the -mesomolecule formation rate in
solid deuterium.Comment: 6 pages, 2 jpeg-figure
FARNESYL DIPHOSPHATE SYNTHASE (FDRS) AND GERANYLGERANYL DIPHOSPHATE SYNTHASE (GGSP1) GENE POLYMORPHISMS AND EFFICIENCY OF THERAPY WITH BISPHOSPHONATES IN RUSSIAN WOMEN WITH POSTMENOPAUSAL OSTEOPOROSIS: A PILOT STUDY
Genetic factors that are an important hereditary component determining a predisposition to osteoporosis (OP) are 60–80% responsible for bone mineral density (BMD). Some polymorphic genes have been previously shown to affect the efficiency of performed anti-osteoporotic therapy.Objective: to study the impact of farnesyl diphosphate synthase (FDRS) and geranylgeranyl diphosphate synthase (GGSPI) gene polymorphisms on BMD changes during 12-month therapy with bisphosphonates (BP) in women with postmenopausal OP.Subjects and methods. The investigation enrolled 53 women with OP. Spine and proximal femur BMD was determined using X-ray densitometry before and after BP treatment. The -99A/C and -8188T ins/del polymorphisms in the FDPS and GGPS1 genes were investigated using real-time polymerase chain reaction.Results and discussion. The BMD changes were less marked in women with the C allele of C/T -99/C polymorphism in the FDPS gene than those in carriers of the genotype AA: 2.3±3.6 and 4.4±3.8% (р = 0.062) in the spine; 0.6±3.1 and 2.8±4.5% (р = 0.075) in the femoral neck; 0.5±2.9 and 2.5±2.8% (р = 0.020) in the entire femur, respectively. Femoral neck densitometry showed a significantly weaker response to BP treatment in the patients carrying the mutant genotype del/del of GGSP1 -8188T ins/del polymorphism than in those with the wild-type genotype ins/ins (0.8±4.2 and 4.1±2.5%, respectively; р = 0.030). No significant differences for this polymorphism were found in other areas of BMD measurement.Conclusion. The described pilot study has indicated that the examined FDPS and GGSP1 gene polymorphisms may be predictors for a response to BP therapy in patients with OP. Further investigations that will contribute to the choice of the most effective therapy for this disease are needed to confirm our results
DBSolve Optimum: a software package for kinetic modeling which allows dynamic visualization of simulation results
<p>Abstract</p> <p>Background</p> <p>Systems biology research and applications require creation, validation, extensive usage of mathematical models and visualization of simulation results by end-users. Our goal is to develop novel method for visualization of simulation results and implement it in simulation software package equipped with the sophisticated mathematical and computational techniques for model development, verification and parameter fitting.</p> <p>Results</p> <p>We present mathematical simulation workbench DBSolve Optimum which is significantly improved and extended successor of well known simulation software DBSolve5. Concept of "dynamic visualization" of simulation results has been developed and implemented in DBSolve Optimum. In framework of the concept graphical objects representing metabolite concentrations and reactions change their volume and shape in accordance to simulation results. This technique is applied to visualize both kinetic response of the model and dependence of its steady state on parameter. The use of the dynamic visualization is illustrated with kinetic model of the Krebs cycle.</p> <p>Conclusion</p> <p>DBSolve Optimum is a user friendly simulation software package that enables to simplify the construction, verification, analysis and visualization of kinetic models. Dynamic visualization tool implemented in the software allows user to animate simulation results and, thereby, present them in more comprehensible mode. DBSolve Optimum and built-in dynamic visualization module is free for both academic and commercial use. It can be downloaded directly from <url>http://www.insysbio.ru</url>.</p
Computers from plants we never made. Speculations
We discuss possible designs and prototypes of computing systems that could be
based on morphological development of roots, interaction of roots, and analog
electrical computation with plants, and plant-derived electronic components. In
morphological plant processors data are represented by initial configuration of
roots and configurations of sources of attractants and repellents; results of
computation are represented by topology of the roots' network. Computation is
implemented by the roots following gradients of attractants and repellents, as
well as interacting with each other. Problems solvable by plant roots, in
principle, include shortest-path, minimum spanning tree, Voronoi diagram,
-shapes, convex subdivision of concave polygons. Electrical properties
of plants can be modified by loading the plants with functional nanoparticles
or coating parts of plants of conductive polymers. Thus, we are in position to
make living variable resistors, capacitors, operational amplifiers,
multipliers, potentiometers and fixed-function generators. The electrically
modified plants can implement summation, integration with respect to time,
inversion, multiplication, exponentiation, logarithm, division. Mathematical
and engineering problems to be solved can be represented in plant root networks
of resistive or reaction elements. Developments in plant-based computing
architectures will trigger emergence of a unique community of biologists,
electronic engineering and computer scientists working together to produce
living electronic devices which future green computers will be made of.Comment: The chapter will be published in "Inspired by Nature. Computing
inspired by physics, chemistry and biology. Essays presented to Julian Miller
on the occasion of his 60th birthday", Editors: Susan Stepney and Andrew
Adamatzky (Springer, 2017
Search for the Radiative Capture d+d->^4He+\gamma Reaction from the dd\mu Muonic Molecule State
A search for the muon catalyzed fusion reaction dd --> ^4He +\gamma in the
dd\mu muonic molecule was performed using the experimental \mu CF installation
TRITON and NaI(Tl) detectors for \gamma-quanta. The high pressure target filled
with deuterium at temperatures from 85 K to 800 K was exposed to the negative
muon beam of the JINR phasotron to detect \gamma-quanta with energy 23.8 MeV.
The first experimental estimation for the yield of the radiative deuteron
capture from the dd\mu state J=1 was obtained at the level n_{\gamma}\leq
2\times 10^{-5} per one fusion.Comment: 9 pages, 3 Postscript figures, submitted to Phys. At. Nuc
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