975 research outputs found
Topographic conditions of soil drainage of Vladimir Opolie
This article demonstrates an approach to digital mapping of soil drainage in Vladimir Opolie controlled by topographic conditions. Topographic conditions of the key area are described by a digital terrain model and morphometric parameters with resolution of 30 m. The variety of soil drainage is represented by soil survey data of the RSFSR Goskomzem, which includes 170 soil observations with morphological characteristic of the degree of soil hydromorphism. Linear combination of the most significant morphometric parameters is calculated by the means of canonical discriminant analysis. This combination also interpreted as topographically induced soil drainage explains 70% of spatial variation of soil hydromorphism. Scores above 0.5 relate to gray forest soils of well drained moraine-erosional plains, gently and steep slopes of valleys. Scores below 0.5 relate to gleyic grey forest soils of shallow slopes of plains, deep valleys and depressions with poor soil drainage conditions
SOIL-AGRO-ECOLOGICAL ASSESSMENT OF THE ARABLE LAND OF THE VALDAI UPLAND BASED ON THE GENERAL SURVEY
A methodical approach to the digital mapping of the arable lands area depending on their soil-agroecological and positional conditions is proposed. The approach was tested on a model plot located on the Valdai Upland with an area of 160 thousand ha. Small-scale agricultural development of the poorly dissected moraine plains is limited by the wide distribution of overmoistened soils. Using the traditional discriminant analysis, a measure of the topographically determined duration of soil overmoistening was calculated based on a comparison of the morphological diagnostics of water regime and topography runoff properties according to the grid elements of 30 Γ 30 m. The drainability range was determined for the arable lands of XVIII century, reconstructed according to the materials of the General Survey. This allowed us to determine the potential area of the arable lands for this period. The area of arable lands, which is characterized by favorable conditions of transport accessibility and soil drainability, was 12Β %. At the same time, reconstructed area contained 5Β %. In the subsistence economy of the XVIII century more than a half of the potential arable lands of the model region turned out to be undeveloped
ADRENERGIC REGULATION OF IMMUNE RESPONSE UNDER EXPERIMENTAL THYROTOXICOSIS IN RATS
It was established that a changes of antibody production and reaction of delayedβtype hypersensitivity at the local immune response to thymus-dependent antigen were opposite in rats with varying severity of experimental thyrotoxicosis β stimulation under a mild form of thyrotoxicosis and depression under more severe form. The increase in glucocorticoid level may be involved in the mechanism of immunosuppression under severe form thyrotoxicosis. The administration of agonist or antagonist of beta-adrenoceptors to animals with thyrotoxicosis led to the significant modification of changes of an immune response parameters, that confirms the participation of an increase in the sensitivity to beta-adrenergic regulation of immune system cells in immunomodulation under thyrotoxicosis
High frequency magnetic oscillations of the organic metal -(ET)ZnBr(CHCl) in pulsed magnetic field of up to 81 T
De Haas-van Alphen oscillations of the organic metal
-(ET)ZnBr(CHCl) are studied in pulsed magnetic
fields up to 81 T. The long decay time of the pulse allows determining reliable
field-dependent amplitudes of Fourier components with frequencies up to several
kiloteslas. The Fourier spectrum is in agreement with the model of a linear
chain of coupled orbits. In this model, all the observed frequencies are linear
combinations of the frequency linked to the basic orbit and to the
magnetic-breakdown orbit .Comment: 6 pages, 4 figure
Π ΡΡΡΠΊΠΈΠΉ Π‘Π΅Π²Π΅Ρ Π² ΠΈΡΡΠΎΡΠΈΡΠ΅ΡΠΊΠΎΠΉ Π΄ΠΈΠ½Π°ΠΌΠΈΠΊΠ΅: ΡΠ°Π·ΡΡΡΠ΅Π½ΠΈΠ΅ ΠΏΡΠΎΠ΅ΠΊΡΠ° ΠΊΡΠ»ΡΡΡΡΠ½ΠΎΠΉ ΠΊΠ»Π°Π΄ΠΎΠ²ΠΎΠΉ ΡΡΡΡΠΊΠΎΠ³ΠΎ Π½Π°ΡΠΎΠ΄Π° ΠΈ ΡΠΎΠ²ΡΠ΅ΠΌΠ΅Π½Π½ΡΠΉ ΠΊΡΠΈΠ·ΠΈΡ ΡΡΠ½ΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ Π½Π°ΡΠΈΠΎΠ½Π°Π»ΠΈΠ·ΠΌΠ°
ΠΠ° ΠΎΡΠ½ΠΎΠ²Π΅ ΠΈΡΡΠΎΡΠΈΡΠ΅ΡΠΊΠΈΡ
, ΡΠΎΡΠΈΠΎΠ»ΠΎΠ³ΠΈΡΠ΅ΡΠΊΠΈΡ
, ΡΡΠ½ΠΎΠ³ΡΠ°ΡΠΈΡΠ΅ΡΠΊΠΈΡ
ΠΈ Π΄Π΅ΠΌΠΎΠ³ΡΠ°ΡΠΈΡΠ΅ΡΠΊΠΈΡ
Π΄Π°Π½Π½ΡΡ
ΡΠ°ΡΡΠΌΠ°-ΡΡΠΈΠ²Π°ΡΡΡΡ ΠΊΡΠ»ΡΡΡΡΠ½ΡΠ΅ ΠΈ ΡΡΠ½ΠΎΠΏΠΎΠ»ΠΈΡΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΠΏΡΠΎΡΠ΅ΡΡΡ, ΠΏΡΠΎΠΈΡΡ
ΠΎΠ΄ΠΈΠ²ΡΠΈΠ΅ Π½Π° ΠΠ²ΡΠΎΠΏΠ΅ΠΉΡΠΊΠΎΠΌ/Π ΡΡΡΠΊΠΎΠΌ Π‘Π΅Π²Π΅ΡΠ΅ Π½Π° ΠΏΡΠΎΡΡΠΆΠ΅Π½ΠΈΠΈ Π΄Π»ΠΈΡΠ΅Π»ΡΠ½ΠΎΠ³ΠΎ ΠΈΡΡΠΎΡΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ ΠΏΠ΅ΡΠΈΠΎΠ΄Π°. ΠΠΎΠΊΠ°Π·Π°Π½ΠΎ, ΡΡΠΎ ΠΌΠ½ΠΎΠ³ΠΎΠ²Π΅ΠΊΠΎΠ²ΠΎΠΉ ΠΏΡΠΎΡΠ΅ΡΡ ΠΊΠΎΠ»ΠΎΠ½ΠΈΠ·Π°ΡΠΈΠΈ Π ΡΡΡΠΊΠΎΠ³ΠΎ Π‘Π΅Π²Π΅ΡΠ° ΠΏΡΠΈΠ²Π΅Π» ΠΊ ΡΠΎΡΠΌΠΈΡΠΎΠ²Π°Π½ΠΈΡ Π΅Π΄ΠΈΠ½ΠΎΠΉ ΠΈΡΡΠΎΡΠΈΠΊΠΎ-ΠΊΡΠ»ΡΡΡΡΠ½ΠΎΠΉ ΠΏΡΠΎΠ²ΠΈΠ½ΡΠΈΠΈ, ΠΊΠΎΡΠΎΡΠ°Ρ Π² ΡΠΎΠ²Π΅ΡΡΠΊΠΈΠ΅ Π³ΠΎΠ΄Ρ Π±ΡΠ»Π° ΡΠ°Π·Π΄Π΅Π»Π΅Π½Π° Π½Π° ΠΎΡΠ΄Π΅Π»ΡΠ½ΡΠ΅ Π½Π°ΡΠΈΠΎΠ½Π°Π»ΡΠ½ΠΎ-Π³ΠΎΡΡΠ΄Π°ΡΡΡΠ²Π΅Π½Π½ΡΠ΅ Π°Π½ΠΊΠ»Π°Π²Ρ, Π½ΠΎ ΡΡΠ½ΠΎΠΊΡΠ»ΡΡΡΡΠ½ΡΠ΅ ΠΈΠ·ΠΌΠ΅Π½Π΅Π½ΠΈΡ ΠΏΠΎΡΠ»Π΅Π΄Π½ΠΈΡ
Π΄Π΅ΡΡΡΠΈΠ»Π΅ΡΠΈΠΉ ΡΠ°ΠΊΡΠΈΡΠ΅ΡΠΊΠΈ ΡΠ΅ΠΊΠΎΠ½ΡΡΡΡΠΈΡΠΎΠ²Π°Π»ΠΈ ΠΏΡΠ΅ΠΆΠ½ΠΈΠΉ ΠΊΡΠ»ΡΡΡΡΠ½ΡΠΉ Π»Π°Π½Π΄ΡΠ°ΡΡ ΡΠ΅Π³ΠΈΠΎΠ½Π°, ΡΡΠΎ ΡΠΎΠ·Π΄Π°Π΅Ρ ΠΊΡΠ»ΡΡΡΡΠ½ΡΡ ΠΈ ΠΈΠ΄Π΅ΠΉΠ½ΡΡ ΠΎΡΠ½ΠΎΠ²Ρ Π΄Π»Ρ ΡΠ΅Π³ΠΈΠΎΠ½Π°Π»ΡΠ½ΠΎΠΉ ΠΈΠ½ΡΠ΅Π³ΡΠ°ΡΠΈΠΈ
Limitations on the superposition principle: superselection rules in non-relativistic quantum mechanics
The superposition principle is a very basic ingredient of quantum theory.
What may come as a surprise to many students, and even to many practitioners of
the quantum craft, is tha superposition has limitations imposed by certain
requirements of the theory. The discussion of such limitations arising from the
so-called superselection rules is the main purpose of this paper. Some of their
principal consequences are also discussed. The univalence, mass and particle
number superselection rules of non-relativistic quantum mechanics are also
derived using rather simple methods.Comment: 22 pages, no figure
Nonlinear electrochemical relaxation around conductors
We analyze the simplest problem of electrochemical relaxation in more than
one dimension - the response of an uncharged, ideally polarizable metallic
sphere (or cylinder) in a symmetric, binary electrolyte to a uniform electric
field. In order to go beyond the circuit approximation for thin double layers,
our analysis is based on the Poisson-Nernst-Planck (PNP) equations of dilute
solution theory. Unlike most previous studies, however, we focus on the
nonlinear regime, where the applied voltage across the conductor is larger than
the thermal voltage. In such strong electric fields, the classical model
predicts that the double layer adsorbs enough ions to produce bulk
concentration gradients and surface conduction. Our analysis begins with a
general derivation of surface conservation laws in the thin double-layer limit,
which provide effective boundary conditions on the quasi-neutral bulk. We solve
the resulting nonlinear partial differential equations numerically for strong
fields and also perform a time-dependent asymptotic analysis for weaker fields,
where bulk diffusion and surface conduction arise as first-order corrections.
We also derive various dimensionless parameters comparing surface to bulk
transport processes, which generalize the Bikerman-Dukhin number. Our results
have basic relevance for double-layer charging dynamics and nonlinear
electrokinetics in the ubiquitous PNP approximation.Comment: 25 pages, 17 figures, 4 table
Therapeutic complement targeting in ANCA-associated vasculitides and thrombotic microangiopathy
Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAVs) are a group of systemic autoimmune disorders characterized by necrotizing inflammation of medium-to-small vessels, a relative paucity of immune deposits, and an association with detectable circulating ANCAs. AAVs include granulomatosis with polyangiitis (renamed from Wegener's granulomatosis), microscopic polyangiitis, and eosinophilic granulomatosis with polyangiitis (Churg-Strauss syndrome). Until recently, AAVs have not been viewed as complement-mediated disorders. However, recent findings predominantly from animal studies demonstrated a crucial role of the complement system in the pathogenesis of AAVs. Complement activation or defects in its regulation have been described in an increasing number of acquired or genetically driven forms of thrombotic microangiopathy. Coinciding with this expanding spectrum of complement-mediated diseases, the question arises as to which AAV patients might benefit from a complement-targeted therapy. Therapies directed against the complement system point to the necessity of a genetic workup of genes of complement components and regulators in patients with AAV. Genetic testing together with pluripotent stem cells and bioinformatics tools may broaden our approach to the treatment of patients with aggressive forms of AAV
Single and molecular ion irradiation-induced effects in GaN : experiment and cumulative MD simulations
An investigation of mechanisms of enhancement of irradiation-induced damage formation in GaN under molecular in comparison to monatomic ion bombardment is presented. Ion-implantation-induced effects in wurtzite GaN bombarded with 0.6 keV amu(-1) F, P, PF2, PF4, and Ag ions at room temperature are studied experimentally and by cumulative MD simulation in the correct irradiation conditions. In the low dose regime, damage formation is correlated with a reduction in photoluminescence decay time, whereas in the high dose regime, it is associated with the thickness of the amorphous/disordered layer formed at the sample surface. In all the cases studied, a shift to molecular ion irradiation from bombardment by its monatomic constituents enhances the damage accumulation rate. Implantation of a heavy Ag ion, having approximately the same mass as the PF4 molecule, is less effective in surface damage formation, but leads to noticeably higher damage accumulation in the bulk. The cumulative MD simulations do not reveal any significant difference in the total amount of both point defects and small defect clusters produced by light monatomic and molecular ions. On the other hand, increased production of large defect clusters by molecular PF4 ions is clearly seen in the vicinity of the surface. Ag ions produce almost the same number of small, but more large defect clusters compared to the others. These findings show that the higher probability of formation of large defect clusters is important mechanism of the enhancement of stable damage formation in GaN under molecular, as well as under heavy monatomic ion irradiation.Peer reviewe
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