Dynamic modelling and validation of the metal/flux interface in continuous casting

This paper concerns the development and validation (using an oil/water system) of a finite volume computer model of the continuous casting process for steel flat products. The emphasis is on hydrodynamic aspects and in particular the dynamic behaviour of the metal/slag interface due to the momentum imparted by the submerged entry nozzle (SEN) jets that bring the metal into the mould. Instability and wave action encourage the entrainment of inclusions into the melt affecting product quality. To track the interface between oil and water a new implicit algorithm was developed, called the Counter Diffusion Method. To prevent numerical damping of low frequency waves, a time-filtered version of the k- model was incorporated in the model. The physics of the interface dynamics are affected by density stratification and surface interfacial tension, with additional source terms introduced in the turbulence model to account for the former effect. Gas bubbles were modelled using a Lagrangian tracking method. The model was validated against experimental measurements obtained in a water model apparatus at Arcelor Research. Silicon oil was used to represent the lighter layer whilst air was pumped through the SEN to represent the argon

Genetical stability and osteogenic ability of mesenchimal stem cells on demineralized bone matrices

Journal of Osseointegration Volume 7, Issue 1, 1 March 2015, Pages 2-7 Open Access Genetical stability and osteogenic ability of mesenchimal stem cells on demineralized bone matrices (Article) Pozzuoli, A.a, Gardin, C.b, Aldegheri, R.a, Bressan, E.c, Isola, M.d, Calvo-Guirado, J.L.e, Biz, C.a, Arrigoni, P.a, Feroni, L.b, Zavan, B.b a Department of Surgical,Oncological and Gastroenterological Sciences, University of Padua, Padua, Italy b Department of Biomedical Sciences, University of Padua, Padua, Italy c Department of Neurosciences, University of Padua, Padua, Italy d Department of Animal Medicine, Production and Health (MAPS), Italy e Department of General Dentistry, Faculty of Medicine and Dentistry, University of Murcia, Murcia, Spain Hide additional affiliations View references (44) Abstract Aim: Tissue engineering is a rapidly expanding field with regard to the use of biomaterials and stem cells in the orthopedic surgery. Many experimental studies have been done to understand the best characteristics of cells, materials and laboratory methods for safe clinical applications. The aim of this study was to compare the ability of 2 different human demineralized bone matrices (DBMs), the one enriched and the other not enriched with hyaluronic acid, to stimulate in vitro the proliferation and the osteogenic differentiation of human adipose-derived stem cells (ADSCs) seeded onto an osteoconductive scaffold. Materials and Methods: ADSCs were isolated, by enzymatic digestion, from abdominal adipose tissue of 5 patients undergoing cosmetic lipoaspiration surgery. ADSCs were then seeded onto a 3D scaffold in the presence of the two different osteoinductive matrices of human demineralized bone and evaluated for proliferation and osteogenic differentiation. The safety of the methods was verified using array-Comparative Genomic Hybridization (array-CGH). Results: ADSCs were able to differentiate in osteogenic sense. Both DBMs showed the ability to induce osteogenic differentiation of the cells. Conclusion: array-CGH showed no changes at genome level, thus confirming the safety of materials and method

Efeito da aplicação de inseticidas na floração da macieira sobre Apis mellifera L. (Hymenoptera: Apidae).

Os inseticidas Bacillus thuringiensis (Dipel 100mL.100L-1) e Novaluron (Rimon 100 CE 40 ml.100L-1) são registrados para o controle de Lepidoptera na cultura da macieira. O objetivo deste trabalho foi avaliar o efeito da aplicação destes inseticidas no período de floração da macieira sobre Apis mellifera. O experimento foi conduzido na safra 2014/2015 em Fraiburgo, SC, utilizando pomares de macieira com 5 hectares

Microlasers based on effective index confined slow light modes in photonic crystal waveguides

We present the design, theory and experimental implementation of a low modal volume microlaser based on a line-defect 2D-photonic crystal waveguide. The lateral confinement of low-group velocity modes is controlled by the post-processing of 1 to 3μm wide PMMA strips on top of two dimensional photonic crystal waveguides. Modal volume around 1.3 (λ/n)3can be achieved using this scheme. We use this concept to fabricate microlaser devices from an InP-based heterostructure including InAs0.65P0.35quantum wells emitting around 1550nm and bonded onto a fused silica wafer. We observe stable, room-temperature laser operation with an effective lasing threshold around 0.5mW. © 2008 Optical Society of America

Traditional landscape and rural development: comparative study in three terraced areas in northern, central and southern Italy to evaluate the efficacy of GAEC standard 4.4 of cross compliance

The recent National Strategic Plan 2007-2013 has introduced landscape as a strategic objective of the rural sector. This represents a minor revolution in the way of visualizing the role of the landscape, together with that of agriculture and the rural territory as a whole, and demonstrates the importance of treating the landscape with a systematic point of view. As part of the Efficond project, three sample areas have been identified, each of about 800-1000 hectares, in zones with important historical - cultural landscapes that are included in the National Catalogue of Historical Rural Landscapes. For each sample area a methodology has been applied, defined Historical Cultural Evaluation Approach, developed as part of a project for the monitoring of the Tuscan landscape that we have simplified and adapted. This methodology is based on the consideration that the landscape is the result of the centuries-old interaction between man and the environment, and so to define an element of the landscape as characteristic it is necessary to evaluate the land use dynamics and landscape changes that took place in the past, identifying those that have persisted for a long time, are slowly evolving or stabilized. The study of the historical landscape, which in the proposed methodology refers to the 50’s, has been done through the interpretation and analysis of aerial photographs taken on the GAI flight in 1954, and has allowed the characteristic, traditional and historical elements of that landscape to be identified and an insight to be gained into the cultural identity of the area. Through the creation of specific indices of density and intensity of the terracing obtained by photo-interpretation, field surveys and GIS elaborations, it was possible to classify the sample areas for this specific and important landscape element, compare the results in two periods and evaluate their frequency in the territory. Multi-temporal comparative analysis is being used increasingly often, especially for the study of territories of value, and in our case has been accompanied both by mapping of the landscape dynamics, which identifies the areas subject to transformations in the considered period, and by tables and figures that allow the evolution of a unit of land use to be followed, observing how this has evolved over time. The evaluation of these evolutionary dynamics has then been integrated with a set of indices, in part borrowed from landscape ecology, and in part specifically developed for areas historically shaped by man, which demonstrate that the landscape has become less fragmented and that the layout of fields has been adapted to a different agricultural model that has profoundly changed the structure of the traditional landscape. The efficacy of the laws protecting the characteristic elements of the landscape is strictly linked to the maintenance of its diversity and typicality and conservation of the complexity of the landscape mosaic. Its evaluation necessitates a historical analysis of the evolutionary dynamics conducted at a purely local level

Caracterização Agronômica da Amoreira-preta Cultivada no Sul do Estado do Paraná.

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Citrate Mediates Crosstalk between Mitochondria and the Nucleus to Promote Human Mesenchymal Stem Cell In Vitro Osteogenesis

Citrate, generated in the mitochondria, is a key metabolite that might link metabolism with signaling, chromatin structure and transcription to orchestrate mesenchymal stem cells (MSCs) fate determination. Based on a detailed morphological analysis of 3D reconstruction of mitochondria and nuclei in single cells, we identified contact sites between these organelles that drastically increase in volume and number during the early stage of mesenchymal stem cell differentiation. These contact sites create a microdomain that facilitates exchange of signals from mitochondria to the nucleus. Interestingly, we found that the citrate derived from mitochondria is necessary for osteogenic lineage determination. Indeed, inhibition of the citrate transporter system dramatically affected osteogenesis, reduced citrate levels that could be converted in α-ketoglutarate, and consequently affected epigenetic marker H3K9me3 associated with the osteogenesis differentiation process. These findings highlight that mitochondrial metabolites play key regulatory roles in the MSCs differentiation process. Further in-depth investigation is needed to provide novel therapeutic strategies in the field of regenerative medicine

Stride-level analysis of mouse open field behavior using deep-learning-based pose estimation.

Gait and posture are often perturbed in many neurological, neuromuscular, and neuropsychiatric conditions. Rodents provide a tractable model for elucidating disease mechanisms and interventions. Here, we develop a neural-network-based assay that adopts the commonly used open field apparatus for mouse gait and posture analysis. We quantitate both with high precision across 62 strains of mice. We characterize four mutants with known gait deficits and demonstrate that multiple autism spectrum disorder (ASD) models show gait and posture deficits, implying this is a general feature of ASD. Mouse gait and posture measures are highly heritable and fall into three distinct classes. We conduct a genome-wide association study to define the genetic architecture of stride-level mouse movement in the open field. We provide a method for gait and posture extraction from the open field and one of the largest laboratory mouse gait and posture data resources for the research community

Mineral-doped poly(L-lactide) acid scaffolds enriched with exosomes improve osteogenic commitment of human adipose-derived mesenchymal stem cells

Exosomes derived from mesenchymal stem cells are extracellular vesicles released to facilitate cell communication and function. Recently, polylactic acid (PLA), calcium silicates (CaSi), and dicalcium phosphate dihydrate (DCPD) have been used to produce bioresorbable functional mineral-doped porous scaffolds-through thermally induced phase separation technique, as materials for bone regeneration. The aim of this study was to investigate the effect of mineral-doped PLA-based porous scaffolds enriched with exosome vesicles (EVs) on osteogenic commitment of human adipose mesenchymal stem cells (hAD-MSCs). Two different mineral-doped scaffolds were produced: PLA-10CaSi-10DCPD and PLA-5CaSi-5DCPD. Scaffolds surface micromorphology was investigated by ESEM-EDX before and after 28 days immersion in simulated body fluid (HBSS). Exosomes were deposited on the surface of the scaffolds and the effect of exosome-enriched scaffolds on osteogenic commitment of hAD-MSCs cultured in proximity of the scaffolds has been evaluated by real time PCR. In addition, the biocompatibility was evaluated by direct-contact seeding hAD-MSCs on scaffolds surface-using MTT viability test. In both formulations, ESEM showed pores similar in shape (circular and elliptic) and size (from 10\u201330 \ub5m diameter). The porosity of the scaffolds decreased after 28 days immersion in simulated body fluid. Mineral-doped scaffolds showed a dynamic surface and created a suitable bone-forming microenvironment. The presence of the mineral fillers increased the osteogenic commitment of hAD-MSCs. Exosomes were easily entrapped on the surface of the scaffolds and their presence improved gene expression of major markers of osteogenesis such as collagen type I, osteopontin, osteonectin, osteocalcin. The experimental scaffolds enriched with exosomes, in particular PLA-10CaSi-10DCPD, increased the osteogenic commitment of MSCs. In conclusion, the enrichment of bioresorbable functional scaffolds with exosomes is confirmed as a potential strategy to improve bone regeneration procedures