137 research outputs found

    Formation and Development of the Training System for Innovative Development of Regional Industry

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    The paper determines tendencies of modern economy development. The key role in the expanded reproduction of innovation processes in the regions in modern conditions belongs to the enhancement of human capital. Regions are actively increasing their efforts in creating innovative infrastructure, knowledge-intensive industries, while success of regional development is directly related to the effectiveness and cohesion of all innovation infrastructure elements. An indispensable condition for the successful development of innovative infrastructure and high-tech industries is the region economy saturation with highly qualified personnel, particularly mining, trained in view of the projected trends of innovative development

    Dynamic Behavior in Piezoresponse Force Microscopy

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    Frequency dependent dynamic behavior in Piezoresponse Force Microscopy (PFM) implemented on a beam-deflection atomic force microscope (AFM) is analyzed using a combination of modeling and experimental measurements. The PFM signal comprises contributions from local electrostatic forces acting on the tip, distributed forces acting on the cantilever, and three components of the electromechanical response vector. These interactions result in the bending and torsion of the cantilever, detected as vertical and lateral PFM signals. The relative magnitudes of these contributions depend on geometric parameters of the system, the stiffness and frictional forces of tip-surface junction, and operation frequencies. The dynamic signal formation mechanism in PFM is analyzed and conditions for optimal PFM imaging are formulated. The experimental approach for probing cantilever dynamics using frequency-bias spectroscopy and deconvolution of electromechanical and electrostatic contrast is implemented.Comment: 65 pages, 15 figures, high quality version available upon reques

    Thermodynamic theory of epitaxial ferroelectric thin films with dense domain structures

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    A Landau-Ginsburg-Devonshire-type nonlinear phenomenological theory is presented, which enables the thermodynamic description of dense laminar polydomain states in epitaxial ferroelectric thin films. The theory explicitly takes into account the mechanical substrate effect on the polarizations and lattice strains in dissimilar elastic domains (twins). Numerical calculations are performed for PbTiO3 and BaTiO3 films grown on (001)-oriented cubic substrates. The "misfit strain-temperature" phase diagrams are developed for these films, showing stability ranges of various possible polydomain and single-domain states. Three types of polarization instabilities are revealed for polydomain epitaxial ferroelectric films, which may lead to the formation of new polydomain states forbidden in bulk crystals. The total dielectric and piezoelectric small-signal responses of polydomain films are calculated, resulting from both the volume and domain-wall contributions. For BaTiO3 films, strong dielectric anomalies are predicted at room temperature near special values of the misfit strain.Comment: 19 pages, 8 figure

    Food insecurity and its determinants among adults in North and South India.

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    This is the final version. Available from BMC via the DOI in this record. Availability of data and materials: The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.BACKGROUND: Food insecurity is a major public health problem worldwide. In India, there are limited food insecurity assessment studies using a conventionally accepted method like the Food Insecurity Experience Scale (FIES), developed by the Food and Agricultural Organization (FAO). This study aims to measure food insecurity using the FIES and explore its determinants and association with body mass index (BMI) among Indian adults.  METHODS: In a cross-sectional study, we used FIES to measure food security in a sample of 9005 adults residing in North and South India. Using questionnaires, socio-demographic factors, dietary intake and food security data were collected. The dietary diversity scores (FAO-IDDS) and food insecurity scores (FAO-FIES) were calculated. Body size was measured and BMI was calculated.  RESULTS: The mean age of the study participants was 52.4 years (± 11.7); half were women and half resided in rural areas. Around 10% of the participants reported having experienced (mild or moderate or severe) food insecurity between October 2018 and February 2019. Dietary diversity (measured by FAO's Individual Dietary Diversity Scores, IDDS) was low and half of the participants consumed ≤ 3 food groups/day. The mean BMI was 24.7 kg/m2. In the multivariate analysis, a lower IDDS and BMI were associated with a higher FIES. The place of residence, gender and wealth index were important determinants of FIES, with those residing in South India, women and those belonging to the poorest wealth index reporting higher food insecurity. CONCLUSION: Food security is understudied in India. Our study adds important evidence to the literature. Despite having marginal food insecurity, high prevalence of low diet quality, especially among women, is disconcerting. Similar studies at the national level are warranted to determine the food insecurity situation comprehensively in India and plan appropriate policy actions to address it effectively, to attain the key Sustainable Development Goals (SDG).Wellcome TrustEli Lille

    Mesoscale flux-closure domain formation in single-crystal BaTiO3

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    Over 60 years ago, Charles Kittel predicted that quadrant domains should spontaneously form in small ferromagnetic platelets. He expected that the direction of magnetization within each quadrant should lie parallel to the platelet surface, minimizing demagnetizing fields,and that magnetic moments should be configured into an overall closed loop, or flux-closure arrangement. Although now a ubiquitous observation in ferromagnets, obvious flux-closure patterns have been somewhat elusive in ferroelectric materials. This is despite the analogous behaviour between these two ferroic subgroups and the recent prediction of dipole closure states by atomistic simulations research. Here we show Piezoresponse Force Microscopy images of mesoscopic dipole closure patterns in free-standing, single-crystal lamellae of BaTiO3. Formation of these patterns is a dynamical process resulting from system relaxation after the BaTiO3 has been poled with a uniform electric field. The flux-closure states are composed of shape conserving 90° stripe domains which minimize disclination stresses

    Maternal Dietary Supplementation with Oligofructose-Enriched Inulin in Gestating/Lactating Rats Preserves Maternal Bone and Improves Bone Microarchitecture in Their Offspring

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    This study received financial support from Abbott Nutrition, a commercial company, and coauthors PBV, MM, JMLP and RR are employees of Abbott Nutrition. There are two patents related with the data presented (EP 2502507 A1 and EP 2745706 A1).Some of these results were presented in the 7th World Congress of DOHaD (2011) and in the World Congress on Osteoporosis, Osteoarthritis and Musculoskeletal Disease (WCO-IOF-ESCEO) (2014).Nutrition during pregnancy and lactation could exert a key role not only on maternal bone, but also could influence the skeletal development of the offspring. This study was performed in rats to assess the relationship between maternal dietary intake of prebiotic oligofructose-enriched inulin and its role in bone turnover during gestation and lactation, as well as its effect on offspring peak bone mass/architecture during early adulthood. Rat dams were fed either with standard rodent diet (CC group), calcium-fortified diet (Ca group), or prebiotic oligofructose-enriched inulin supplemented diet (Pre group), during the second half of gestation and lactation. Bone mineral density (BMD) and content (BMC), as well as micro-structure of dams and offspring at different stages were analysed. Dams in the Pre group had significantly higher trabecular thickness (Tb.Th), trabecular bone volume fraction (BV/TV) and smaller specific bone surface (BS/BV) of the tibia in comparison with CC dams. The Pre group offspring during early adulthood had an increase of the lumbar vertebra BMD when compared with offspring of CC and Ca groups. The Pre group offspring also showed significant increase versus CC in cancellous and cortical structural parameters of the lumbar vertebra 4 such as Tb.Th, cortical BMD and decreased BS/BV. The results indicate that oligofructose-enriched inulin supplementation can be considered as a plausible nutritional option for protecting against maternal bone loss during gestation and lactation preventing bone fragility and for optimizing peak bone mass and architecture of the offspring in order to increase bone strength.This study was funded by Abbott Nutrition R&D, and co-authors PBV, MM, JMLP and RR receive salary from Abbott Nutrition

    Assessment of Fluid Cavitation Threshold Using a Polymeric Split Hopkinson Bar-Confinement Chamber Apparatus

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    The authors would like to acknowledge the Natural Sciences and Engineering Research Council of Canada for financial support, and Compute Canada and Sharcnet for providing the necessary computing resources.Mild Traumatic Brain Injury (mTBI) has been associated with blast exposure resulting from the use of improvised explosive devices (IEDs) in recent and past military conflicts. Experimental and numerical models of head blast exposure have demonstrated the potential for high negative pressures occurring within the head at the contre-coup location relative to the blast exposure, and it has been hypothesized that this negative pressure could result in cavitation of Cerebrospinal Fluid (CSF) surrounding the brain, leading to brain tissue damage. The cavitation threshold of CSF, the effect of temperature, and the effect of impurities or dissolved gases are presently unknown. In this study, a novel Polymeric Split Hopkinson Pressure Bar and confinement chamber apparatus were used to generate loading in distilled water similar to the conditions in the vicinity of the CSF during blast exposure. Cavitation was identified using high-speed imaging of the event, and a validated numerical model of the apparatus was applied to determine the pressure in the fluid during the exposure. Increasing the water temperature resulted in a decrease in the 50% probability of cavitation from 21 °C (−3320 kPa ± 3%) to 37 °C (−3195 kPa ± 5%) in agreement with the theoretical values, but was not statistically significant. Importantly, the effect of water treatment had a significant effect on the cavitation pressure for water with wetting agent (−3320 kPa ± 3%), degassed water (−1369 kPa ± 16%) and untreated distilled water (−528 kPa ± 25%). Thus, reducing dissolved gases through degassing or the use of a wetting agent significantly increases the cavitation pressure and reduces the variability of the cavitation pressure threshold
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