761 research outputs found
Increasing the efficiency of investments on survey of abundant land for their return to agricultural us
The "âState program for the effective involvement of abundant agricultural land in the use and the development of the reclamation complex of the Russian Federationâ for 2021â2030" assumes the return of 12 million hectares out of 44 million hectares of all abandoned agricultural land (AAL) in the Russian Federation. The costs of 12 million hectares survey can be considered productive, while the costs of surveying the remaining 32 million hectares should be considered unproductive. The application of the new geoinformation database of âSoils of agricultural lands of the Russian Federationâ (DB SALRU) developed by the Federal Research Centre âV.VÂ Dokuchaev Soil Sience Instituteâ allows reduction of unproductive costs. By the example of the Vladimir region, a typical Russian region with AAL, the option of ranking AAL by their quality was demonstrated to determine the order of their return to agricultural use. The soil quality criteria are the bonitet and the normative yield of grain crops, which are part of the DB SALRU. It is proposed to consider the expenditures on the survey of AAL for the soils, which are first to be returned to agricultural use, as productive costs. These soils occupy 25% of the AAL of the region. The best quality soils are characterized by more than 40 points of bonitet and the standard yield of grain crops of more than 20 centners/ha. The cost of surveying the lands of the first order of returning to agricultural use is 10 million 80 thousand rubles. Survey of AAL soils of IIâIV orders of involvement in agricultural use, with relatively poor quality compared to the soils of the first order, is proposed to be conducted in the case of expansion of the State program in the future. This would save the unproductive expenses for the survey of AAL for the Vladimir region by 30 million 165.5 thousand rubles. The application of the proposed GIS-approach makes it possible to reduce unproductive expenses for the survey of AAL in the Russian Federation nearly by 5.600 million rubles
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
Level of Stress in Students with the Disturbance of Nasal Breathing and Comorbid Disorders
Background. The progressive increase of the number of schoolchildren with adaptation disorders and low level of health in recent years determines the need to assess the characteristics of the psychosomatic status in children and adolescents with various types of somatic pathology, including diseases of ENT organs, accompanied by nasal breathing disorders and hypoxia. It is also necessary to determine the severity of stress in children, for timely prevention and correction of these disorders.Aim: to assess the level of stress in schoolchildren with nasal breathing disorders against the background of nasal diseases and concomitant psychosomatic disorders.Materials and methods. 481 schoolchildren aged 12â17 (boys and girls) were examined. Nasal breathing disorders were assessed by a comprehensive ENT examination, including rhinoscopy, radiography of the sinuses, and olfactometry. The presence and severity of stress were determined by the questionnaire âSocial factors and stressâ.Results. We found that the high level of stress in children with nasal breathing disorders on the background of ENT pathology is more often associated with the high frequency and severity of psychosomatic symptoms: the presence of dorsalgia, asthenic syndrome, chronic headache and frequent episodes of abdominal pain. Moderately and significantly increased levels of stress associated with the presence of children with hypertension, asthenic syndrome, frequent abdominal pain, frequent pain in the cervical spine, panic disorders.Conclusions. Thus, the presence of certain psychosomatic complaints in children with nasal breathing disorders is directly related to the level of stress, which is important to take into account when planning preventive and corrective measures aimed at increasing the adaptive capacity and stress resistance of children. The studies illustrate the need to assess the psychosomatic status and the level of stress in schoolchildren with nasal breathing disorders taking into account their existing comorbid disorders of the psychosomatic spectrum
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
On The Universality Class Of Little String Theories
We propose that Little String Theories in six dimensions are quasilocal
quantum field theories. Such field theories obey a modification of Wightman
axioms which allows Wightman functions (i.e. vacuum expectation values of
products of fundamental fields) to grow exponentially in momentum space.
Wightman functions of quasilocal fields in x-space violate microlocality at
short distances. With additional assumptions about the ultraviolet behavior of
quasilocal fields, one can define approximately local observables associated to
big enough compact regions. The minimum size of such a region can be
interpreted as the minimum distance which observables can probe. We argue that
for Little String Theories this distance is of order {\sqrt N}/M_s.Comment: 25 pages, late
The study of the sorghum genetic diversity using the mulÂŹtiplex microsatellite analysis
This study is focused on evaluation of the genetic structure and diversity of the national sorghum collection. Analyzing the genetic diversity of crop species is of great importance for genetic resources management and food security of any country. Huge genetic diversity of sorghum provides a great opportunity to improve the agronomic characteristics of this crop. The efficiency of microsatellite analysis has been demonstrated in many studies on the genetic diversity of different races and geographical groups of sorghum plants. Development of multiplex PCR analysis systems based on a set of polymorphic microsatellite loci will facilitate genetic tests on a large number of plant samples, thus making the research on sorghum diversity more efficient and comprehensive. A system of multiplex PCR analysis based on 12 polymorphic microsatellite loci was developed to perform single-stage high-throughput screening of cultivated and wild forms preserved in the sorghum germplasm collection. As a result of the microsatellite analysis of 200 sorghum plants, 229 alleles were detected. The studied loci showed high polymorphism. More than 17 alleles were identified in most loci, their polymorphic index content (PIC) ranging from 0.694 to 0.954. The value of the effective multiplex ratio (EMR) in the developed system was estimated at 0.833. The microsatellite analysis of sorghum accessions resulted in obtaining quantized gene expressions profiles, with a DNA profile for each accession, and revealed significant polymorphism among the plants of different sorghum varieties (races). The developed multiplex PCR system was shown to be efficient for evaluation of the genetic diversity and genetic relationships of sorghum plants from different races. The analysis of the obtained data using three bioinformatic techniques, NJ cluster analysis, PCoA, and the Bayesian model-based clustering, helped to classify the analyzed sorghum accessions into cluster groups according to their morphological and agronomic traits
Segre Types of Symmetric Two-tensors in n-Dimensional Spacetimes
Three propositions about Jordan matrices are proved and applied to
algebraically classify the Ricci tensor in n-dimensional Kaluza-Klein-type
spacetimes. We show that the possible Segre types are [1,1...1], [21...1],
[31\ldots 1], [z\bar{z}1...1] and degeneracies thereof. A set of canonical
forms for the Segre types is obtained in terms of semi-null bases of vectors.Comment: 14 pages, LaTeX, replaced due to a LaTex erro
Diffuse-Charge Dynamics in Electrochemical Systems
The response of a model micro-electrochemical system to a time-dependent
applied voltage is analyzed. The article begins with a fresh historical review
including electrochemistry, colloidal science, and microfluidics. The model
problem consists of a symmetric binary electrolyte between parallel-plate,
blocking electrodes which suddenly apply a voltage. Compact Stern layers on the
electrodes are also taken into account. The Nernst-Planck-Poisson equations are
first linearized and solved by Laplace transforms for small voltages, and
numerical solutions are obtained for large voltages. The ``weakly nonlinear''
limit of thin double layers is then analyzed by matched asymptotic expansions
in the small parameter , where is the
screening length and the electrode separation. At leading order, the system
initially behaves like an RC circuit with a response time of
(not ), where is the ionic diffusivity, but nonlinearity
violates this common picture and introduce multiple time scales. The charging
process slows down, and neutral-salt adsorption by the diffuse part of the
double layer couples to bulk diffusion at the time scale, . In the
``strongly nonlinear'' regime (controlled by a dimensionless parameter
resembling the Dukhin number), this effect produces bulk concentration
gradients, and, at very large voltages, transient space charge. The article
concludes with an overview of more general situations involving surface
conduction, multi-component electrolytes, and Faradaic processes.Comment: 10 figs, 26 pages (double-column), 141 reference
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