532 research outputs found
Conforming identification of the fundamental matrix in image matching problem
The article considers the conforming identification of the fundamental matrix in the image matching problem. The method consists in the division of the initial overdetermined system into lesser dimensional subsystems. On these subsystems, a set of solutions is obtained, from which a subset of the most conforming solutions is defined. Then, on this subset the resulting solution is deduced. Since these subsystems are formed by all possible combinations of rows in the initial system, this method demonstrates high accuracy and stability, although it is computationally complex. A comparison with the methods of least squares, least absolute deviations, and the RANSAC method is drawn.This research was supported by the RF Ministry of Education and Science (Project # 2.7891.2017/6.7)
ЭТИОЛОГИЧЕСКАЯ СТРУКТУРА И ДИФФЕРЕНЦИАЛЬНАЯ ДИАГНОСТИКА САЛЬМОНЕЛЛЕЗА ПТИЦ
The article presents the results of a study of the etiological structure and differential diag-nostic signs of avian salmonellosis. When identifying bacteria isolated from 128 blood samples of chickens with the use of rapid test "Salmonella latex kit" established the dominance of cultures of the microorganisms Salmonella spp. — of 10.94% (14 samples); 10 strains (71,43%) were attributed to Salmonella gallinarum, 4 (of 28.57%) to Salmonella pullorum. The overall level of resistance of Salmonella to ampicillin — 57,58%; tetracycline — 60,61%; streptomycin — 66,67%; had to 57,58%; 60,61% and 66,67% are sensitivity to norfloxacin amounted to 69,70%, to ceftazidime — 78,79%, enrofloxacin — 57,58%, ciprofloxacin — 69,70% of the tested strains. At postmortem examination the most frequently detected signs of pericarditis, hemorrhagic pneumonia, aeroscout, catarrhal-hemorrhagic enteritis, perihepatitis, hyperplasia of the spleen. The most frequently detected signs of pericarditis, aeroscout, catarrhal-hemorrhagic gastroenterocolitis, perihepatitis, inflam-mation of the ovaries, hyperplasia of the spleen. Revealed signs of congestive hyperemia, macrophage reaction, hyperplasia and plasmocytomas of lymphocyte transformation, increase the permeability of microcirculatory vessels, lymphoid-cellular infil-tration of loose fibrous connective tissue, perivascular oedema, disseminated thrombosis, proliferation of lymphocytes from lymph nodes, spleen, liver, and pancreas. In violation of the porosity of the blood vessels of serous membranes of organs were observed extensive serous oedema, the output of the formed elements of blood and the loss of fibrinogen.В статье представлены результаты изучения этиологической структуры и дифференциально-диагностических признаков сальмонеллеза птиц. При идентификации бактерий, выделенных из 128 проб крови цыплят, с применением экспресстеста «Salmonella latex kit» установлено доми-нирование культур микроорганизмов Salmonella spp. - 10,94% (14 проб); 10 штаммов (71,43%) были отнесены к Salmonella gallinarum, 4 (28,57%) - к Salmonella pullorum. Общий уровень резистентности сальмонелл к ампициллину - 57,58%, тетрациклину - 60,61%; стрептомицину - 66,67%; чувствительность к норфлоксацину - 69,70%; цефтазидиму - 78,79%; энрофлоксацину - 57,58%; ципрофлоксацину - 69,70% испытанных штаммов. При патологоанатомическом исследовании наиболее часто выявлялись признаки перикардита, геморрагической пневмонии, аэросаккулита, катарально-геморрагического энтерита, перигепатита, гиперплазия селезенки. Наиболее часто выявлялись признаки перикардита, аэросаккулита, катарально-геморрагического гастроэнтероколита, перигепатита, воспаление яичников, гиперплазия селезенки. Выявляли признаки застойной гиперемии, макрофагальной реакции, гиперплазии и плазмоцитарной трансформации лимфоцитов, повышения проницаемости сосудов микроциркуляторного русла, лимфоидно-клеточной инфильтрации рыхлой волокнистой соединительной ткани, периваскулярного отека тканей, диссеминированного тромбоза, пролиферации лимфоцитов лимфатических узлов, селезенки, печени, поджелудочной железы. При нарушении порозности кровеносных сосудов серозных оболочек органов наблюдались обширные серозные отеки, выход форменных элементов крови и выпадение фибриногена
СОВРЕМЕННЫЕ ТЕХНОЛОГИИ В ХИРУРГИЧЕСКОМ ЛЕЧЕНИИ ПОСЛЕДСТВИЙ ТРАВМЫ ЧЕРЕПА И ГОЛОВНОГО МОЗГА
The paper presents main types of surgically relevant posttraumatic lesions in 4136 patients with skull vault as well as skull base defects, craniofacial deformities, recurrent CSF leaks, arterio-venous fistulas, aneurysms and pseudoaneurysms etc. Classification of TBI sequelae and complications as well as its clinical course grading is presented. The use of modern neuroimaging techniques for studying pathophysiologic mechanisms and complications of TBI has been demonstrated. Special emphasis was given to minimally invasive and reconstructive surgery; computer modeling with subsequent full-copy stereolitographic laser implant setup was shown which is of great importance in cases of large and complex skull base and craniofacial deformities. Patient selection for transcranial and endonasal CSF leak closure techniques was justified. Treatment of post-traumatic vascular injuries using Serbinenko balloon-catheters as well as modern techniques such as stents, coils and embolization has been demonstrated. В сообщении (созданном по материалам доклада, представленного на Сессии общего собрания РАМН, Санкт-Петербург, 14−15 июня 2012 г.) представлены основные хирургически значимые формы посттравматической патологии у 4136 пациентов с дефектами и деформациями костей свода, основания черепа и лицевого скелета, рецидивирующей ликвореей, артериосинусными соустьями, истинными и ложными аневризмами и др. Разработана классификация последствий и осложнений черепно-мозговой травмы, а также периодизация ее клинического течения. Раскрыты возможности современных нейровизуализационных технологий распознавания и исследования патогенеза последствий и осложнений черепно-мозговой травмы. Особое внимание уделено реконструктивной и минимально инвазивной хирургии, детально описан метод компьютерного моделирования и последующего стереолитографического лазерного воспроизведения полномасштабных копий черепа, его дефектов и имплантатов, что особенно значимо при обширных и сложных краниобазальных и краниофациальных повреждениях. Обосновано дифференцированное применение интракраниальных и эндоназальных доступов для закрытия хронических ликворных фистул. Вместе с впервые созданной в НИИ нейрохирургии им. Н.Н. Бурденко методикой эндоваскулярной реконструкции магистральных сосудов с помощью баллонов-катетеров Ф.А. Сербиненко представлены новые подходы, опирающиеся на современные технологии с использованием стентов, микроспиралей и эмболизирующих композиций.
Nonlinear spinor field in Bianchi type-I Universe filled with viscous fluid: numerical solutions
We consider a system of nonlinear spinor and a Bianchi type I gravitational
fields in presence of viscous fluid. The nonlinear term in the spinor field
Lagrangian is chosen to be , with being a self-coupling
constant and being a function of the invariants an constructed from
bilinear spinor forms and . Self-consistent solutions to the spinor and
BI gravitational field equations are obtained in terms of , where
is the volume scale of BI universe. System of equations for and \ve,
where \ve is the energy of the viscous fluid, is deduced. This system is
solved numerically for some special cases.Comment: 15 pages, 4 figure
Gravitational excitons from extra dimensions
Inhomogeneous multidimensional cosmological models with a higher dimensional
space-time manifold are investigated under dimensional reduction. In the
Einstein conformal frame, small excitations of the scale factors of the
internal spaces near minima of an effective potential have a form of massive
scalar fields in the external space-time. Parameters of models which ensure
minima of the effective potentials are obtained for particular cases and masses
of gravitational excitons are estimated.Comment: Revised version --- 12 references added, Introduction enlarged, 20
pages, LaTeX, to appear in Phys.Rev.D56 (15.11.97
Cross-Correlation Earthquake Precursors in the Hydrogeochemical and Geoacoustic Signals for the Kamchatka Peninsula
We propose a new type of earthquake precursor based on the analysis of
correlation dynamics between geophysical signals of different nature. The
precursor is found using a two-parameter cross-correlation function introduced
within the framework of flicker-noise spectroscopy, a general statistical
physics approach to the analysis of time series. We consider an example of
cross-correlation analysis for water salinity time series, an integral
characteristic of the chemical composition of groundwater, and geoacoustic
emissions recorded at the G-1 borehole on the Kamchatka peninsula in the time
frame from 2001 to 2003, which is characterized by a sequence of three groups
of significant seismic events. We found that cross-correlation precursors took
place 27, 31, and 35 days ahead of the strongest earthquakes for each group of
seismic events, respectively. At the same time, precursory anomalies in the
signals themselves were observed only in the geoacoustic emissions for one
group of earthquakes.Comment: 21 pages, 5 figures, 1 table; to be published in "Acta Geophysica".
arXiv admin note: substantial text overlap with arXiv:1101.147
Compaction of Rods: Relaxation and Ordering in Vibrated, Anisotropic Granular Material
We report on experiments to measure the temporal and spatial evolution of
packing arrangements of anisotropic, cylindrical granular material, using
high-resolution capacitive monitoring. In these experiments, the particle
configurations start from an initially disordered, low-packing-fraction state
and under vertical vibrations evolve to a dense, highly ordered, nematic state
in which the long particle axes align with the vertical tube walls. We find
that the orientational ordering process is reflected in a characteristic, steep
rise in the local packing fraction. At any given height inside the packing, the
ordering is initiated at the container walls and proceeds inward. We explore
the evolution of the local as well as the height-averaged packing fraction as a
function of vibration parameters and compare our results to relaxation
experiments conducted on spherically shaped granular materials.Comment: 9 pages incl. 7 figure
Quantum mechanics: Myths and facts
A common understanding of quantum mechanics (QM) among students and practical
users is often plagued by a number of "myths", that is, widely accepted claims
on which there is not really a general consensus among experts in foundations
of QM. These myths include wave-particle duality, time-energy uncertainty
relation, fundamental randomness, the absence of measurement-independent
reality, locality of QM, nonlocality of QM, the existence of well-defined
relativistic QM, the claims that quantum field theory (QFT) solves the problems
of relativistic QM or that QFT is a theory of particles, as well as myths on
black-hole entropy. The fact is that the existence of various theoretical and
interpretational ambiguities underlying these myths does not yet allow us to
accept them as proven facts. I review the main arguments and counterarguments
lying behind these myths and conclude that QM is still a
not-yet-completely-understood theory open to further fundamental research.Comment: 51 pages, pedagogic review, revised, new references, to appear in
Found. Phy
Anisotropic cosmological models with a perfect fluid and a term
We consider a self-consistent system of Bianchi type-I (BI) gravitational
field and a binary mixture of perfect fluid and dark energy given by a
cosmological constant. The perfect fluid is chosen to be the one obeying either
the usual equation of state, i.e., p = \zeta \ve, with or
a van der Waals equation of state. Role of the term in the evolution
of the BI Universe has been studied.Comment: 8 pages, 8 Figure
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