320 research outputs found
Mathematical model for monitoring carbon dioxide concentration in industrial greenhouses
ArticleProcesses of monitoring and control the industrial greenhouses microclimate play a
decisive role in growing crops under protected cultivation. Providing optimal climatic conditions
in the production process of greenhouse agricultural products requires solving the scientific and
applied problem of developing and researching a mathematical model for monitoring carbon
dioxide concentration in industrial greenhouses. The proposed model takes into account the
processes of diffusion and absorption of carbon dioxide, the geometric parameters of
greenhouses, as well as the types and vegetation periods of crops grown under protected
cultivation. Time characteristics of the carbon dioxide dynamics process under greenhouse
conditions are estimated. Quantitative estimates of the diffusion transfer duration and carbon
dioxide absorption are made for indeterminate varieties of tomatoes during planting and fruiting
periods. Recommendations are given on the development of an adaptive methodology for the
functioning and structural and algorithmic organization of computerized monitoring and
management system for carbon dioxide top-dressing modes for greenhouse crops. The necessity
of improving the proposed mathematical model and confirming the adequacy of its
implementation efficiency on yield indicators of greenhouse crops is substantiated
Individual educational trajectory of teaching Russian language to students with hearing impairments in general education school
The article is devoted to the problems of improving the quality of education of children with hearing impairments in secondary general education school.Статья посвящена проблемам совершенствования качества обучения детей младшего школьного возраста с нарушениями слуха (слабослышащих) в условиях общеобразовательной школы
Comparison of Postural Recovery Following Short and Long Duration Spaceflights
INTRODUCTION: Post-flight postural ataxia reflects adaptive changes to vestibulo-spinal reflexes and control strategies adopted for movement in weightlessness. Quantitative measures obtained during computerized dynamic posturography (CDP) from US and Russian programs provide insight into the effect of spaceflight duration in terms of both the initial decrements and recovery of postural stability. METHODS: CDP was obtained on 117 crewmembers following Shuttle flights lasting 4-17 days, and on 64 crewmembers following long-duration missions lasting 48-380 days. Although the number and timing of sessions varied, the goal was to characterize postural recovery pooling similar measures from different research and flight medicine programs. This report focuses on eyes closed, head erect conditions with either a fixed or sway-referenced base of support. A smaller subset of subjects repeated the sway-referenced condition while making pitch head movements (+/- 20deg at 0.33Hz). Equilibrium scores were derived from peak-to-peak anterior-posterior sway. Fall probability was modeled using Bayesian statistical methods to estimate parameters of a logit function. RESULTS: The standard Romberg condition was the least sensitive. Longer duration flights led to larger decrements in stability with sway-reference support during the first 1-2 days, although the timecourse of recovery was similar across flight duration with head erect. Head movements led to increased incidence of falls during the first week, with a significantly longer recovery following long duration flights. CONCLUSIONS: The diagnostic assessment of postural instability, and differences in the timecourse of postural recovery between short and long flight durations, are more pronounced during unstable support conditions requiring active head movements
Determining the effect of cadmium on embryogenesis in isolated administration and in combination with selenium and germanium citrates
Cadmium compounds found in biological systems form the ecological crisis of the planet. An urgent task for researchers is to determine the morphological changes that occur in the body under the action of cadmium compounds in both prenatal and postnatal ontogenesis. The article discusses the results of effect of intragastric administration of cadmium chloride/cadmium citrate in isolation and in combination with selenium and germanium citrates on embryogenesis of pregnant female rats. The aspect of the accumulation of cadmium salts in the liver of a 20-day-old embryo by polyelement analysis was also studied. The use of multielement analysis showed that the highest level of cadmium accumulation in the liver of embryos was found in the group of isolated administration of cadmium chloride. It has been proven that cadmium citrate accumulates in the liver to a lesser extent than cadmium chloride in the liver. The accumulation of cadmium chloride with selenium citrates, germanium in the groups of combined administration showed a decrease in the cadmium content in the liver of embryos. An analysis of the basic indicators of embryonic development of the experiment proved the embryotoxic effect of cadmium salts during enteral administration in modeling chronic cadmium intoxication, which is expressed in a decrease in the number of embryos in the litter and an increase in embryonic mortality in relation to the control group at all studied developmental periods. A decrease in embryonic mortality and an increase in the number of embryos at all stages of gestation in the experiment with the combined administration of cadmium salts with germanium citrate and selenium citrate indicates their antagonistic effect on cadmium embryotoxicity
МОДЕЛЬ КОМПЛЕКСНОЙ СИСТЕМЫ ОЦЕНКИ ИННОВАЦИОННОЙ ДЕЯТЕЛЬНОСТИ ПРЕДПРИЯТИЯ
The paper contains an analysis of existing indices which are used for evaluation of the activity at the innovative enterprises. An original model of a complex system for evaluation of the innovative enterprise activity is proposed in the paper. Проведен анализ существующих показателей, применяемых для оценки деятельности на инновационных предприятиях, и предложена оригинальная модель комплексной системы оценки инновационной деятельности предприятия
Functional Sensory-Motor Performance Following Long Term Space Flight: The First Results of "Field Test" Experiment
The effect that extended-duration space flights may have on human space travelers, including exploration missions, is widely discussed at the present time. Specifically, there is an increasing amount of evidence showing that the physical capacity of cosmonauts is significantly reduced after long-duration space flights. It is evident that the most impaired functions are those that rely on gravity, particularly up right posture and gait. Because of the sensorimotor disturbances manifested in the neurology of the posture and gait space flight and postflight changes may also be observed in debilitating motion sickness. While the severity of particular symptoms varies, disturbances in spatial orientation and alterations in the accuracy of voluntary movements are persistently observed after long-duration space flights. At this time most of the currently available data are primarily descriptive and not yet suitable for predicting operational impacts of most sensorimotor decrements observed upon landing on planetary surfaces or asteroids. In particular there are no existing data on the recovery dynamics or functionality of neurological, cardiovascular or muscle performance making it difficult to model or simulate the cosmonauts' activity after landing and develop the appropriate countermeasure that will ensure the rapid and safe recovery of crewmembers immediately after landing in what could be hostile environments. However and as a starting position, the videos we have acquired during recent data collection following the long duration flights of cosmonauts and astronauts walking and performing other tasks shortly after return from space flight speak volumes about their level of deconditioning. A joint Russian-American team has developed a new study specifically to address the changes in crewmembers performance and the recovery of performance with the intent of filling the missing data gaps. The first (pilot) phase of this study includes recording body kinematics and quantifying the coordination and timing of relatively simple basic movements - transition from seated and prone positions to standing, walking, stepping over obstacles, tandem walking, muscle compliance, as well as characteristics of postural sway and orthostatic tolerance. Testing for changes in these parameters have been initiated in the medical tent at the landing site. The first set of experiments showed that during the first hour after landing, cosmonauts and astronauts were able to execute (although slower and with more effort than preflight) simple movements such as egress from a seated or prone position and also to remain standing for 3.5 minutes without exhibiting pronounced cardiovascular changes. More challenging tests, however, demonstrated a prominent reduction in coordination - the obstacle task, for example, was performed at much slower speed and with a marked overestimation of the obstacle height and tandem walking was greatly degraded suggesting significant changes in proprioception, brainstem and vestibular function. There is some speculation that the neural changes, either from the bottom-up or top down may be long lasting; requiring compensatory responses that will modify or mask the adverse responses we have observed. Furthermore, these compensatory responses may actually be beneficial, helping achieve a more rapid adaptation to both weightlessness and a return to earth
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
Electrical spinal stimulation, and imagining of lower limb movements to modulate brain-spinal connectomes that control locomotor-like behavior
© 2018 Gerasimenko, Sayenko, Gad, Kozesnik, Moshonkina, Grishin, Pukhov, Moiseev, Gorodnichev, Selionov, Kozlovskaya and Edgerton. Neuronal control of stepping movement in healthy human is based on integration between brain, spinal neuronal networks, and sensory signals. It is generally recognized that there are continuously occurring adjustments in the physiological states of supraspinal centers during all routines movements. For example, visual as well as all other sources of information regarding the subject's environment. These multimodal inputs to the brain normally play an important role in providing a feedforward source of control. We propose that the brain routinely uses these continuously updated assessments of the environment to provide additional feedforward messages to the spinal networks, which provides a synergistic feedforwardness for the brain and spinal cord. We tested this hypothesis in 8 non-injured individuals placed in gravity neutral position with the lower limbs extended beyond the edge of the table, but supported vertically, to facilitate rhythmic stepping. The experiment was performed while visualizing on the monitor a stick figure mimicking bilateral stepping or being motionless. Non-invasive electrical stimulation was used to neuromodulate a wide range of excitabilities of the lumbosacral spinal segments that would trigger rhythmic stepping movements. We observed that at the same intensity level of transcutaneous electrical spinal cord stimulation (tSCS), the presence or absence of visualizing a stepping-like movement of a stick figure immediately initiated or terminated the tSCS-induced rhythmic stepping motion, respectively. We also demonstrated that during both voluntary and imagined stepping, the motor potentials in leg muscles were facilitated when evoked cortically, using transcranial magnetic stimulation (TMS), and inhibited when evoked spinally, using tSCS. These data suggest that the ongoing assessment of the environment within the supraspinal centers that play a role in planning a movement can routinely modulate the physiological state of spinal networks that further facilitates a synergistic neuromodulation of the brain and spinal cord in preparing for movements
Experimental Evaluation of the Protective Efficacy of Tick-Borne Encephalitis (TBE) Vaccines Based on European and Far-Eastern TBEV Strains in Mice and in Vitro
Tick-borne encephalitis (TBE), caused by the TBE virus (TBEV), is a serious public health threat in northern Eurasia. Three subtypes of TBEV are distinguished. Inactivated vaccines are available for TBE prophylaxis, and their efficacy to prevent the disease has been demonstrated by years of implication. Nevertheless, rare TBE cases among the vaccinated have been registered. The present study aimed to evaluate the protective efficacy of 4 TBEV vaccines against naturally circulating TBEV variants. For the first time, the protection was evaluated against an extended number of phylogenetically distinct TBEV strains isolated in different years in different territories. The protective effect did not strongly depend on the infectious dose of the challenge virus or the scheme of vaccination. All vaccines induced neutralizing antibodies in protective titers against the TBEV strains used, although the vaccines varied in the spectra of induced antibodies and protective efficacy. The protective efficacy of the vaccines depended on the individual properties of the vaccine strain and the challenge virus, rather than on the subtypes. The neutralization efficiency appeared to be dependent not only on the presence of antibodies to particular epitopes and the amino acid composition of the virion surface but also on the intrinsic properties of the challenge virus E protein structure
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