Reference community Siberian pine forests of Western Siberia as a local example of rational environmental management: anthropogenic disturbance analysis

The article describes geo-botanic characteristics of three massifs of community (situated in the vicinities of settlements) Siberian pine forests, both reference and valuable wood forests with dominance of Pinus sibirica Du Tour., growing in the mid- and southern taiga subzones of the Western Siberia natural taiga zone, Tomsk region. The results of the comparative analysis of the degree of anthropogenic disturbance in Siberian pine forests ecosystems’ composition and plant species communities’ participation are presented based on a hemerobiality scale.     

Low-level atmospheric jets as main mechanism of long-range transport of power plant plumes in the Lake Baikal Region

This paper considers some peculiarities of anthropogenic admixtures propagation from large regional Coal Power Plants towards the South Baikal using experimental data and model estimates. Results of observations show that the main mechanism for transfer of atmospheric admixtures towards the South Baikal is low-level atmospheric jets having high velocity and a weak turbulent mixing. A weak mixing of emitted plume with the surrounding air (within a jet flow) results in deficiency of oxidants in it and in slowing of chemical transformation of some admixtures during the transfer.     

Phonon Raman spectra of colloidal CdTe nanocrystals: effect of size,non-stoichiometry and ligand exchange

Resonant Raman study reveals the noticeable effect of the ligand exchange on the nanocrystal (NC) surface onto the phonon spectra of colloidal CdTe NC of different size and composition. The oleic acid ligand exchange for pyridine ones was found to change noticeably the position and width of the longitudinal optical (LO) phonon mode, as well as its intensity ratio to overtones. The broad shoulder above the LO peak frequency was enhanced and sharpened after pyridine treatment, as well as with decreasing NC size. The low-frequency mode around 100 cm^-1 which is commonly related with the disorder-activated acoustical phonons appears in smaller NCs but is not enhanced after pyridine treatment. Surprisingly, the feature at low-frequency shoulder of the LO peak, commonly assigned to the surface optical phonon mode, was not sensitive to ligand exchange and concomitant close packing of the NCs. An increased structural disorder on the NC surface, strain and modified electron-phonon coupling is discussed as the possible reason of the observed changes in the phonon spectrum of ligand-exchanged CdTe NCs.     

Geometrical modelling of angle warp interlock fabrics

A geometrical modelling approach has been developed which predicts all the necessary geometrical parameters for multilayer angle warp interlock weaves. The model requires tow and weaver data as input and gives fabric thickness, warp and weft crimp angle, areal weight and fibre volume fraction (FVF) as outputs. In order to validate the model we have woven three angle warp interlock woven reinforcements, having same number of total layers, on a conventional loom, using carbon multifilament tows in warp and glass multifilament tows in weft. The depth of the binder (maximum number of layers traversed by the binding warp in vertical plane) was maximum for the first variant (5). The binder tow traversed all the five layers so that this variant is termed as through-the-thickness angle interlock. For the second variant it was reduced to an intermediate level (3), whereas for the third one it was minimum (2) so as to conceive a layer-to-layer interlock structure. The geometry of such woven reinforcements can be categorised in terms of crimp amplitude and cross-sectional shape of the warp and weft tows. These two vary with the structure of the woven fabric and weaving parameters, ultimately influencing the areal weight, size of the unit cell and FVF of the fabric reinforcement. Results obtained show that the modelling approach can be successfully applied to calculate necessary fabric geometry parameters from minimum number of manufacturer and weaver data.     

Status of design and experimental activity on module of lithium divertor for KTM tokamak

The projects of ITER and DEMO reactors showed that there are serious difficulties with solving the issues of plasma facing elements (PFE) based on the solid materials. Problems of PFE can be overcome by the use of liquid lithium. Application of lithium will allow to create a self-renewal and MHD stable liquid metal surface of the in-vessel devices possessing practically unlimited service life. Realization of these advantages is based on use of so-called lithium capillary-porous system (CPS) – new material, in which liquid lithium fills a solid matrix from porous material. The progress in development of lithium technology and also lithium experiments in the tokamaks TFTR, T-11M, T-10, FTU, NSTX, LTX, HT-7 and stellarator TJ II is a good basis for development of the project of steady-state operating lithium divertor module for Kazakhstan tokamak. At present the lithium divertor module for KTM tokamak is development and manufacturing. The paper describes main design features of the module of lithium divertor (MLD). The first step of the hydraulic tests of MLD with fully assembled external thermo-stabilization system, which was connected to in-vessel lithium unit, were performed using ethanol as a model heat transfer media. Test results of MLD have shown that operating parameters of designed and manufactured system for thermo-stabilization are sufficient for proper operation; basic hydraulic characteristics of the system are close to expected values.     

Nanostructured severe plastic deformation processed titanium for orthodontic mini-implants

Titanium mini-implants have been successfully used as anchorage devices in Orthodontics. Commercially pure titanium (cpTi) was recently replaced by Ti-6Al-4 V alloy as the mini-implant material base due to the higher strength properties of the alloy. However, the lower corrosion resistance and the lower biocompatibility have been lowering the success rate of Ti-6Al-4 V mini-implants. Nanostructured titanium (nTi) is commercially pure titanium that was nanostructured by a specific technique of severe plastic deformation. It is bioinert, does not contain potentially toxic or allergic additives, and has higher specific strength properties than any other titanium applied in medical implants. The higher strength properties associated to the higher biocompatibility make nTi potentially useful for orthodontic mini-implant applications, theoretically overcoming cpTi and Ti-6Al-4 V mini-implants. The purposes of the this work were to process nTi, to mechanically compare cpTi, Ti-6Al-4 V, and nTi mini-implants by torque test, and to evaluate both the surface morphology and the fracture surface characteristics of them by SEM. Torque test results showed significant increase in the maximum torque resistance of nTi mini-implants when compared to cpTi mini-implants, and no statistical difference between Ti-6Al-4 V and nTi mini-implants. SEM analysis demonstrated smooth surface morphology and transgranular fracture aspect for nTi mini-implants. Since nanostructured titanium mini-implants have mechanical properties comparable to titanium alloy mini-implants, and biocompatibility comparable to commercially pure titanium mini-implants, it is suggestive that nanostructured titanium can replace Ti-6Al-4 V alloy as the material base for mini-implants.     

A randomised cross-over trial in healthy adults indicating improved absorption of omega-3 fatty acids by pre-emulsification

Background  

The health benefits of increased intakes of omega-3 fatty acids are well established but palatability often presents a problem. The process of emulsification is used in the food industry to provide a wider spectrum of use, often with the result of increased consumption. Moreover, as emulsification is an important step in the digestion and absorption of fats, the pre-emulsification process may enhance digestion and absorption. In this study the levels of plasma fatty acid and triacylglycerol (TAG) following the ingestion of either an oil mixture or an emulsified oil mixture have been compared.     

Human Mesenchymal Stromal Cell-Derived Exosomes Promote In Vitro Wound Healing by Modulating the Biological Properties of Skin Keratinocytes and Fibroblasts and Stimulating Angiogenesis

Bone marrow-derived mesenchymal stromal cells (MSCs) are major players in regenerative therapies for wound healing via their paracrine activity, mediated partially by exosomes. Our purpose was to test if MSC-derived exosomes could accelerate wound healing by enhancing the biological properties of the main cell types involved in the key phases of this process. Thus, the effects of exosomes on (i) macrophage activation, (ii) angiogenesis, (iii) keratinocytes and dermal fibroblasts proliferation and migration, and (iv) the capacity of myofibroblasts to regulate the turnover of the extracellular matrix were evaluated. The results showed that, although exosomes did not exhibit anti-inflammatory properties, they stimulated angiogenesis. Exposure of keratinocytes and dermal (myo)fibroblasts to exosomes enhanced their proliferation and migratory capacity. Additionally, exosomes prevented the upregulation of gene expression for type I and III collagen, α-smooth muscle actin, and MMP2 and 14, and they increased MMP13 expression during the fibroblast–myofibroblast transition. The regenerative properties of exosomes were validated using a wound healing skin organotypic model, which exhibited full re-epithelialization upon exosomes exposure. In summary, these data indicate that exosomes enhance the biological properties of keratinocytes, fibroblasts, and endothelial cells, thus providing a reliable therapeutic tool for skin regeneration.     

High-Temperature Oxidation Resistance of Ceramic Matrix Composites Si3N4 – Cf

We have studied the behavior of ceramic matrix composites in the system Si₃N₄ – C_f, reinforced with different types of carbon fibers, at moderate (1100°C) and maximum (1500°C) service temperatures. We have studied the effect of the composition of ceramic matrix composites and the oxidation temperature conditions on their strength properties and microstructure.