The Influence Of Elasticity, Temperature And Fracture On Large Scale Geological Flow

Realistic simulations of earth processes such as faulting, shearing, magma flow, subduction and convection often require the consideration of non-Newtonian Effects such as elasticity and power law creep. As the deformations involved in geological deformation are often large the constitutive relationships must maintain certain geometric terms to ensure that the tensor properties of the model are conserved. A model with such properties is termed as objective. There are a wide range of objective, visco-elasto-plastic models to choose from. The main structural difference between these models consists in the choice of the objective stress rate, e.g. Jaumann, Oldroyd, Truesdell - rates (see Kolymbas and Herle, 2003, for a recent discussion). In this paper we give an outline of a thermo-visco-elastic-plastic model including a discussion of numerical aspects such as the derivation of a consistent incremental form. The viscous part of the deformation involves a combination of both Newtonian and power law creep. Plastic deformations are described by means of a standard Prandtl-Reuss flow rule combined with a von Mises yield criterion. In planetary scale flow modeling the yield criterion is required as a stress limiter during episodic events e.g. in connection with the initiation of subduction. The temperature sensitivity of the viscous deformation is considered by means of an Arrhenius relation involving a pressure dependent reference (melting) temperature. The salient features of the model are first explored by means of analytical and numerical solutions of a simple shear problem for an infinite strip with fixed and prescribed shear velocities on the bottom and top of the layer respectively

Formation of cratonic lithosphere during the initiation of plate tectonics

Earth’s oldest near-surface material, the cratonic crust, is typically underlain by thick lithosphere (>200 km) of Archean age. This cratonic lithosphere likely thickened in a high-compressional-stress environment, potentially linked to the onset of crustal shortening in the Neoarchean. Mantle convection in the hotter Archean Earth would have imparted relatively low stresses on the lithosphere, whether or not plate tectonics was operating, so a high stress signal from the early Earth is paradoxical. We propose that a rapid transition from heat pipe–mode convection to the onset of plate tectonics generated the high stresses required to thicken the cratonic lithosphere. Numerical calculations are used to demonstrate that an existing buoyant and strong layer, representing depleted continental lithosphere, can thicken and stabilize during a lid-breaking event. The peak compressional stress experienced by the lithosphere is 3×–4× higher than for the stagnant-lid or mobile-lid regimes immediately before and after. It is plausible that the cratonic lithosphere has not been subjected to this high stress state since, explaining its long-term stability. The lid-breaking thickening event reproduces features observed in typical Neoarchean cratons, such as lithospheric seismological reflectors and the formation of thrust faults. Paleoarchean “pre-tectonic” structures can also survive the lid-breaking event, acting as strong rafts that are assembled during the compressive event. Together, the results indicate that the signature of a catastrophic switch from a stagnant-lid Earth to the initiation of plate tectonics has been captured and preserved in the characteristics of cratonic crust and lithosphere

Budidaya Sayuran Organik di Lahan Pekarangan pada Kelompok Masyarakat di Kelurahan Naimata dalam Upaya Menopang Ekonomi Keluarga pada Masa Pandemi Covid 19

Abstract - The PKM Program for Organic Vegetable Cultivation in the Yard Land in an Effort to Support the Family Economy During the Covid 19 Pandemic was carried out in the area of ​​RT 17, RW 07, Naimata Village, Kupang City. The main targets to be achieved from this program are: (1) increasing the independence of partners in meeting household food needs; (2) mastery of hydroponic system installation techniques; (3) mastery of hydroponic system plant cultivation technology; (4) mastery of technology for making liquid organic fertilizer based on household organic waste and organic pesticides. The approach method applied in the implementation of this PKM program is the transfer of information and technology transfer through socialization and training activities. Activities carried out include: training on plant cultivation technology with hydroponic and verticulture systems, training on hydroponic equipment installation, as well as training on technology for making liquid organic fertilizers and organic pesticides. After this PKM activity took place, the level of knowledge and skills of partner group members regarding technology for cultivating organik vegetables with a hydroponic system, installation techniques for hydroponic plant cultivation equipment, techniques for making liquid organic fertilizers and organic pesticides have increased significantly. This increase in knowledge and skills is followed by an increase in the interest of partner group members to apply the technology in an effort to fulfil household food by optimally utilizing the yard.   Abstrak – Program PKM Budidaya Sayuran Organik di Lahan Pekarangan Dalam Upaya  Menopang Ekonomi Keluarga Pada Masa Pandemi Covid 19 dilaksanakan di wilayah RT 17, RW 07, Kelurahan Naimata, Kota Kupang. Target utama yang ingin dicapai dari program ini adalah: (1) peningkatan kemandirian mitra dalam memenuhi kebutuhan pangan rumah tangga; (2) penguasaan teknik pembuatan instalasi sistem hidroponik; (3) penguasaan teknologi budidaya tanaman sistem hidroponik; (4) penguasaan teknologi pembuatan pupuk organik cair berbasis sampah organik rumah tangga dan pestisida organik. Metode pendekatan yang diterapkan dalam pelaksanaan program PKM ini adalah transfer informasi dan alih teknologi melalui kegiatan sosialisasi dan pelatihan. Kegiatan yang dilakukan meliputi: pelatihan teknologi budidaya tanaman dengan sistem hidroponik dan vertikultur, pelatihan instalasi peralatan hidroponik, serta pelatihan teknologi pembuatan pupuk organik cair dan pestisida organik. Setelah kegiatan PKM ini berlangsung, tingkat pengetahuan dan keterampilan anggota kelompok mitra tentang teknologi budidaya tanaman sayuran organik dengan sistem hidroponik, terknik instalasi peralatan budidaya daya tanaman hidroponik, teknik pembuatan pupuk organik cair dan pestisida organik mengalami peningkatan secara signifikan. Peningkatan pengetahuan dan keterampilan ini diikuti dengan peningkatan minat anggota kelompok mitra untuk menerapkan teknologi tersebut dalam upaya pemenuhan pangan rumah tangga dengan memanfaatkan lahan pekarang secara optimal

Circulating EGFL7 distinguishes between IUGR and PE: an observational case–control study

Isolated intrauterine growth restriction (IUGR) and preeclampsia (PE) share common placental pathogenesis. Differently from IUGR, PE is a systemic disorder which may also affect liver and brain. Early diagnosis of these conditions may optimize maternal and fetal management. Aim of this study was to assess whether Epidermal Growth Factor-Like domain 7 (EGFL7) dosage in maternal blood discriminates between isolated IUGR and PE. A total of 116 women were enrolled in this case-control study: 12 non-pregnant women, 34 healthy pregnant women, 34 women presenting with isolated IUGR and 36 presenting with PE. Levels of circulating EGFL7 and other known pro- and anti-angiogenic factors were measured by ELISA at different gestational ages (GA). Between 22-25 weeks of gestation, EGFL7 levels in early-onset PE (e-PE) plasma samples were significantly higher than those measured in controls or isolated IUGR samples (69.86 ± 6.17 vs. 19.8 ± 2.5 or 18.8 ± 2.8 µg/ml, respectively). Between 26-34 weeks, EGFL7 levels remained significantly higher in e-PE compared to IUGR. At term, circulating and placental EGFL7 levels were comparable between IUGR and late-onset PE (l-PE). In contrast, circulating levels of PlGF were decreased in both IUGR- and PE- complicated pregnancies, while levels of both sFLT-1 and sENDOGLIN were increased in both conditions. In conclusion, EGFL7 significantly discriminates between isolated IUGR and PE

HDAC4 is necessary for satellite cell differentiation and muscle regeneration

In response to injury, skeletal muscle exhibits high capacity to regenerate and epigenetics controls multiple steps of this process (Giordani et al., 2013). It has been demonstrated in vitro that completion of muscle differentiation requires shuttling of histone deacetylase 4 (HDAC4), a member of class IIa HDACs, from the nucleus to the cytoplasm and consequent activation of MEF2-dependent differentiation genes (McKinsey et al., 2000). In vivo, HDAC4 expression is up-regulated in skeletal muscle upon injury, suggesting a role for this protein in muscle regeneratio

The action of obestatin in skeletal muscle repair: stem cell expansion, muscle growth, and microenvironment remodeling

The development of therapeutic strategies for skeletal muscle diseases, such as physical injuries and myopathies, depends on the knowledge of regulatory signals that control the myogenic process. The obestatin/GPR39 system operates as an autocrine signal in the regulation of skeletal myogenesis. Using a mouse model of skeletal muscle regeneration after injury and several cellular strategies, we explored the potential use of obestatin as a therapeutic agent for the treatment of trauma-induced muscle injuries. Our results evidenced that the overexpression of the preproghrelin, and thus obestatin, and GPR39 in skeletal muscle increased regeneration after muscle injury. More importantly, the intramuscular injection of obestatin significantly enhanced muscle regeneration by simulating satellite stem cell expansion as well as myofiber hypertrophy through a kinase hierarchy. Added to the myogenic action, the obestatin administration resulted in an increased expression of VEGF/VEGFR2 and the consequent microvascularization, with no effect on collagen deposition in skeletal muscle. Furthermore, the potential inhibition of myostatin during obestatin treatment might contribute to its myogenic action improving muscle growth and regeneration. Taken together, our data demonstrate successful improvement of muscle regeneration, indicating obestatin is a potential therapeutic agent for skeletal muscle injury and would benefit other myopathies related to muscle regeneration

INVESTIGATING THE RELATIONSHIP BETWEEN MOVEMENT VARIABILITY, SKILL ACQUISITION AND ADAPTABILITY

Facilitating adaptability is a role attributed to movement variability. The aim of this investigation was to track changes in movement variability during the learning of a novel task where adaptability was expected to be present. A contextual interference design was implemented with sample entropy and vector coding used to quantify joint and coordination variability respectively. Those exposed to high contextual interference were significantly better performed and more adaptable. Significant decreases in coordination variability were found during the learning process for all participants. The more adaptable group also exhibited higher coordination variability at key points providing some support for previous hypotheses on the interaction between, skill acquisition and adaptability. Results have implications for practitioners working in skill acquisition

DBO5 y otros parametros fisico-quimicos como indicadores de contaminación. Río Paraná, Costa Corrientes Capital, Argentina

Se exponen resultados de análisis que permiten evaluar algunas características físicoquímicas del agua del río Paraná. La información se presenta como variaciones de los siguientes parámetros: pH, turbiedad, conductividad, alcalinidad, cloruros, serie nitrogenada y DBO5 (Demanda Bioquímica de Oxígeno), durante el período 2002-2003. Los puntos de monitoreo se eligieron a lo largo de la costa del río en la ciudad de Corrientes, Provincia de Corrientes, Argentina. Permite visualizar y contrastar en principio para explicar al cabo del tiempo algunos cambios en la naturaleza del río Paraná si los hubiere por razones naturales o antrópicas como lo es la represa de Yacyretá. Otros trabajos del LABQUIAM relacionados a este tema, donde se ponen de manifiesto características históricas del río Paraná ya han sido publicados (Acevedo et al., 2004; López et al., 2000)