68 research outputs found
Bush Encroachment of Forest-steppe Landscapes in the Mongolian Part of the Lake Baikal Basin
The character of competitive relationships between woody and shrub vegetation in the southern (Mongolian) part of the Lake Baikal basin was studied via model polygons. Depending on the environmental conditions, native forests are being replaced by different types of shrubs. The main factors contributing to these changesare the aridization of the climate and human activity. It is shown that the current state of shrub communities and their progressive dynamics along the southern border of boreal forests in Mongolia allow us to consider them stable cenoses, which prevent a natural renewal of coniferous (pine, larch) forests in this region. However, some shrub species may be considered indicators of ecotopes’ suitability for natural or artificial reforestation because their ecological requirements are similar to those of forest trees.
Keywords: Lake Baikal basin, ecotone area, destruction of forests, bush encroachmen
Biological activity comparative evaluation of the gene-Activated bone substitutes made of octacalcium phosphate and plasmid DNA carrying VEGF and SDF genes: Part 1 - in vitro
High need for effective bone substitutes and drawbacks of the materials approved for clinical use determine the increasing activity of biomedical research in this area. We have developed gene-Activated bone substitutes consisting of a scaffold based on octacalcium phosphate (OCP) and one of the two variants of plasmid DNA carrying either a gene for vascular endothelial growth factor (VEGF) or two genes encoding VEGF and stromal derived factor- 1α (SDF-1α). The aim of the study was to evaluate the cytotoxicity of the gene-Activated materials and their components, as well as biological activity in vitro. We found that both OCP and gene-Activated bone substitutes did not have any cytotoxicity, but reduced the proliferative activity of human bone marrow-derived multipotent mesenchymal stromal cells: material with doublegene construct decreased cell culture doubling rate of 24.3% more compared with the material carrying plasmid DNA encoding only VEGF. Both gene-Activated materials led to an increase in therapeutic genes mRNA levels, but the material with double-gene system enhanced VEGF protein production greater. Thus, the gene-Activated bone substitutes characterized by the absence of cytotoxic properties and possessed a specific activity increasing expression of the therapeutic genes. However, further studies are needed to detail the identified characteristics and assess the feasibility of the defined biological action in vivo
РЕЗУЛЬТАТЫ ЭКСПЕРИМЕНТАЛЬНЫХ ИССЛЕДОВАНИЙ ДЕТСКОГО ОСЕВОГО НАСОСА «ДОН-3»
Aim. To evaluate the functioning of an implantable pediatric axial pump «DON-3» for bypassing the left ventricle of the heart in experiments on sheep.Materials and methods. Five sheeps at the age of 12–18 months performed paracorporeal installation of the children’s axial pump «DON-3» according to the scheme «left ventricle – aorta».Results. A technique was developed and 5 chronic experiments were conducted on sheep to assess the model of the children’s axial pump «DON-3». The duration of the experiments in this series averaged 9 ± 5 days. The main indicators of hemodynamics, acid-base balance were within the norm. Conducted morphological and histological studies of the kidneys, liver and lungs did not reveal the presence of zones of ischemia and thromboembolism.Conclusion. The results of this series of experiments showed satisfactory results, suggesting further research on the development of prototypes of a pediatric pump for clinical practice. Цель. Оценка функционирования имплантируемого детского осевого насоса «ДОН-3» для обхода левого желудочка сердца в экспериментах на баранах.Материалы и методы. Пяти баранам в возрасте 12–18 месяцев выполнена паракорпоральная установка детского осевого насоса «ДОН-3» по схеме «левый желудочек – аорта».Результаты. Разработана методика и проведены 5 хронических экспериментов на баранах по оценке макета детского осевого насоса «ДОН-3». Длительность экспериментов в данной серии составляла в среднем 9 ± 5 суток. Основные показатели гемодинамики, кислотно-щелочного равновесия находились в пределах нормы. Проведенные морфологические и гистологические исследования почек, печени и легких не выявили наличия зон ишемии и тромбоэмболии.Заключение. Результаты данной серии экспериментов показали удовлетворительные результаты, предполагающие проведение дальнейших исследований по разработке опытных образцов детского насоса для клинической практики.
Boreal forest soil carbon fluxes one year after a wildfire: Effects of burn severity and management
The extreme 2018 hot drought that affected central and northern Europe led to the worst wildfire season in Sweden in over a century. The Ljusdal fire complex, the largest area burnt that year (8995 ha), offered a rare opportunity to quantify the combined impacts of wildfire and post-fire management on Scandinavian boreal forests. We present chamber measurements of soil CO2 and CH4 fluxes, soil microclimate and nutrient content from five Pinus sylvestris sites for the first growing season after the fire. We analysed the effects of three factors on forest soils: burn severity, salvage-logging and stand age. None of these caused significant differences in soil CH4 uptake. Soil respiration, however, declined significantly after a high-severity fire (complete tree mortality) but not after a low-severity fire (no tree mortality), despite substantial losses of the organic layer. Tree root respiration is thus key in determining post-fire soil CO2 emissions and may benefit, along with heterotrophic respiration, from the nutrient pulse after a low-severity fire. Salvage-logging after a high-severity fire had no significant effects on soil carbon fluxes, microclimate or nutrient content compared with leaving the dead trees standing, although differences are expected to emerge in the long term. In contrast, the impact of stand age was substantial: a young burnt stand experienced more extreme microclimate, lower soil nutrient supply and significantly lower soil respiration than a mature burnt stand, due to a thinner organic layer and the decade-long effects of a previous clear-cut and soil scarification. Disturbance history and burn severity are, therefore, important factors for predicting changes in the boreal forest carbon sink after wildfires. The presented short-term effects and ongoing monitoring will provide essential information for sustainable management strategies in response to the increasing risk of wildfire
Climate change and oak growth decline: Dendroecology and stand productivity of a Turkey oak (Quercus cerris L.) old stored coppice in Central Italy
EFFECTIVE STIMULATION WORKERS – BASIS OF ECONOMIC GROWTH COMPANIES
Summary. At the present stage of development of domestic agricultural production is a key strategic direction of the innovative development of the industry. Tasked by the government to effectively modernize the economy reflect the latest scientific and technological progress, innovation, positive perception of new ideas and breakthrough technologies. In this regard, the decisive role played by the information network , computer systems, high production technology and intellectual resources of society, innovative organization of various spheres of human activity , as well as a new level of relations to knowledge. The main driving force of innovation development of agro-industrial production in Russia at the present stage is the human potential to carry out the restructuring of the agricultural sector with the latest achievements of scientific and technical progress. Famous slogan - "cadres decide everything" under the innovation paradigm of reforming the economy is of particular relevance. One of the important reasons for the low level of innovative development of agricultural production is the lack of motivation of creative work in the agricultural workers business organizations. For the development of advanced technologies for improving the quality and reducing the material cost per unit of cash - produ Dima products they do not receive adequate material compensation. This is largely inhibits the activity of employees in the development of advanced low-cost and resource-saving technologies in agricultural production. We propose an original model for innovative employee incentiveing activity and a real contribution to improving the efficiency of the enterprise. To take into account the personal contribution of the employee in additional economic benefit through innovative component and determining bonuses, proposed to use the "coefficient of innovation activity employee" (CIAE). The value of this coefficient is defined as the ratio of profits derived by an enterprise as a result of innovation in a given period to the standard profit on the business plan or the actual profit for the previous period
CENP-F couples cargo to growing and shortening microtubule ends
Dynamic microtubule ends exert pulling and pushing forces on intracellular membranes and organelles. However, the mechanical linkage of microtubule tips to their cargoes is poorly understood. CENP-F is a nonmotor microtubule-binding protein that participates in microtubule binding at kinetochores and in the mitotic redistribution of the mitochondrial network. CENP-F-driven mitochondrial transport is linked to growing microtubule tips, but the underlying molecular mechanisms are unknown. Here we show that CENP-F tracks growing microtubule ends in living cells. In vitro reconstitution demonstrates that microtubule tips can transport mitochondria and CENP-F-coated artificial cargoes over micrometer-long distances during both growing and shrinking phases. Based on these and previous observations, we suggest that CENP-F might act as a transporter of mitochondria and other cellular cargoes by attaching them to dynamic microtubule ends during both polymerization and depolymerization of tubulin
ANALYSIS OF A CHANGE IN THE POSITION OF THE HYOID BONE WHEN DISPLACING THE LOWER JAW IN PATIENTS WITH DENTOFACIAL MALFORMATIONS
Objective. To estimate the magnitude of a change in the position of the hyoid bone when displacing the lower jaw during surgical treatment in patients with dentofacial abnormalities.Material and methods. Fifty patients with dentofacial abnormalities (25 and 25 patients with distal and mesial occlusion, respectively) were examined and treated. All the patients underwent multislice spiral computed tomography before and 6 months after surgery. The authors developed linear quantities to analyze the position of the hyoid bone with respect to the skull base and cervical spine. The paired Wilcoxon signed-rank test was used.Results. None of the examined groups was noted to have a statistically significant change in the distance between the basihyoid and the vertebral column, suggesting that the datum was moderately changed. No case of worse respiratory function was found.Conclusion. Our investigation has revealed that mandible displacement during orthognathic surgery causes no critical change in the position of the hyoid bone and hence it has no significant impact on upper airway patency in this area
A Compact Repetitive High Power Microwave (HPM) Source
Presentation of report at Int. Conference ANTEM/AMEREM, July 5-9, 2010 Ottawa, Canad
A compact high power microwave (HPM) source
Proc. IET European Pulsed Power Conference 200
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