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Coupled hydro-thermo-mechanical modeling of hydraulic fracturing in quasi-brittle rocks using BPM-DEM

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第1期9卷 92-104页

作者： ingrid Tomac Marte Gutierrez Department of Structural Engineering University of California San Diego Department of Civil and Environmental Engineering Colorado School of Mines Department of Geosciences University of Oslo

This paper presents an improved understanding of coupled hydro-thermo-mechanical(HTM) hydraulic fracturing of quasi-brittle rock using the bonded particle model(BPM) within the discrete element method(DEM). BPM has been recently extended by the authors to account for coupled convective econductive heat flow and transport, and to enable full hydro-thermal fluidesolid coupled *** application of the work is on enhanced geothermal systems(EGSs), and hydraulic fracturing of hot dry rock(HDR) is studied in terms of the impact of temperature difference between rock and a flowing fracturing fluid. Micro-mechanical investigation of temperature and fracturing fluid effects on hydraulic fracturing damage in rocks is presented. It was found that fracture is shorter with pronounced secondary microcracking along the main fracture for the case when the convectiveeconductive thermal heat exchange is considered. First, the convection heat exchange during low-viscosity fluid infiltration in permeable rock around the wellbore causes significant rock cooling, where a finger-like fluid infiltration was observed. Second, fluid infiltration inhibits pressure rise during pumping and delays fracture initiation and propagation. Additionally, thermal damage occurs in the whole area around the wellbore due to rock cooling and cold fluid infiltration. The size of a damaged area around the wellbore increases with decreasing fluid dynamic viscosity. Fluid and rock compressibility ratio was found to have significant effect on the fracture propagation velocity.

关键词： Hydro-thermo-mechanical(HTM) modeling Enhanced geothermal systems(EGSs) Discrete element method(DEM) Bonded particle model(BPM) Conductive-convective heat flow and transport Hydraulic fracturing Rock permeability enhancement

Interaction of Mantle Rocks with Crustal Fluids: Sagvandites of the Scandinavian Caledonides

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Journal of Earth Science 2019年第6期30卷 1084-1094页

作者： Kurt Bucher ingrid Stober Mineralogy and Petrology Institute of Earth and Environmental SciencesUniversity of Freiburg79104 FreiburgGermany College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266510China

Sagvandite is an enstatite+magnesite rock formed from dunite or harzburgite bodies occurring as tectonically emplaced fragments from the upper mantle in many orogenic belts by interaction with CO2-bearing crustal fluids at upper amphibolite facies P-T *** bodies occur widespread in distinct nappes in the Scandinavian Caledonides in *** to all of the many sagvandite outcrops is their general structure of radial bundles of very coarse cm-sized enstatite crystals and interstitial *** some strongly resorbed primary olivine is preserved,in addition to minor accessory Cr-spinel and *** dunite to sagvandite conversion is governed by three metasomatic reactions:(1)carbonatization of peridotite by CO2-bearing fluids;(2)interaction with external fluids containing dissolved silica;(3)loss of Mg by dissolution of forsterite in NaCl-rich deep *** progressξoverall of all three reactions in proportions that conserve the volume of the original dunite can explain the observed structure and mode of *** relationship among the progressξof the three reactions suggests that loss of Mg by the ultramafic rock is the dominating process in the iso-volume conversion of dunite to sagvandite.

关键词： sagvandite peridotite fluid-rock interaction metasomatism CO2-sequestration

Bioacoustic variation of swimbladder disturbance sounds in Neotropical doradoid catfishes （Siluriformes： Doradidae, Auchenipteridae）： Potential morphological correlates

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Current Zoology 2012年第1期58卷 171-188页

作者： Kaatz, ingrid M. Stewart, Donald J. Department of Environmental and Forest Biology SUNY College of Environmental Science and Forestry Syracuse NY 13210 USA

Swimbladder disturbance sounds of doradoid catfishes （Doradidae and Aucheniptefidae） demonstrated striking waveform and spectrographic variation. We surveyed sounds of 25 doradoid species in 20 genera comparing these to sounds of four vocal outgroup catfish families. Sounds were either continuous waveforms （lacking interpulses） or pulsed （groups of pulses repeated at fixed temporal intervals）. This is the first evidence for swimbladder calls with fixed interpulse patterns in catfishes. Vocal mechanism components that were similar between doradids and auchenipterids included： swimbladder shape, swimbladder dimensions and sonic muscle-somatic index. Morphological traits that showed variation among taxa and were evaluated for po- tential correlates of call diversity are： 1） diverticula （marginal outpocketings of the swimbladder with no connection to inner ear） and 2） elastic spring apparatus Mtillerian rami （ESA-Mr）. Within the doradid subfamilies and within the Auchenipteridae most species differed significantly in dominant frequency with frequency ranges overlapping to some extent for most. Doradid swim- bladder diverticula did not explain dominant frequency variation within the doradoid superfamily. Some doradids with conical ESA-Mr had the highest dominant frequency sounds. Auchenipterids included both relatively lower and higher dominant fre- quency sound producers but lacked diverticula and had discoidal ESA-Mr. Comparing a phylogeny of doradoid genera with out- group taxa, we infer that complex diverticula and conical ESA-Mr are derived characters within the Doradidae. Species repre- senting outgroup families produced either continuous lower dominant frequency sounds （aspredinids, mochokids and pseudopimelodids） or pulsed higher dominant frequency sounds （pimelodids） [Current Zoology 58 （1）： 171-188, 2012].

关键词： Catfishes Communication Signal evolution Vocal mechanisms

Gneiss-Water Interaction and Water Evolution During the Early Stages of Dissolution Experiments at Room Temperature

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Chinese Journal Of Geochemistry 2003年第4期22卷 302-312页

作者：朱义年 ingrid Stober Kurt Bucher Dept. of Resource and Environmental Engineering Guilin Institute of Technology Geological Survey Baden-Württemberg Institute for Mineralogy Petrology and Geochemistry University of Freiburg

Gneiss\|distilled water interaction at room temperature was investigated with batch\|reactors to study water\|rock reaction and geochemical evolution of the aqueous phase with time. The ion concentrations in water were controlled not only by the dissolution of primary minerals, but also by the precipitation of secondary minerals. The decreasing fraction sizes of gneiss could favor dissolution and precipitation simultaneously. Ca\+\{2+\} and K\++ were the major cations, and HCO\+-\-3 was the major anion in water. All the ions except Ca\+\{2+\} increased in concentration with time. The Ca\+\{2+\} release from the rock to the aqueous phase was initially much faster than the release of K\++, Na\++ and Mg\+\{2+\}. But after about 5-24 hours, the Ca\+\{2+\} concentrations in water decreased very slowly with time and became relatively stable. During the experiment, the water varied from the Ca\|(K)\|HCO\-3\|type water to the K\|Ca\|HCO\-3\|type water, and then to the K\|(Ca,Na)\|HCO\-3\|type water. The water\|gneiss interaction was dominated by the dissolution of K\|feldspar in the solution. The remaining secondary minerals were mainly kaolinite, illite and K(Mg)\|mica.

关键词： gneLss water interaction water evolufion

Collective Resources as a Precursor for Educating Children Toward a Sustainable Global World

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ECNU Review of Education 2019年第4期2卷 396-420页

作者： Jonna Larsson ingrid Pramling Samuelsson Department of Education Communication and LearningUniversity of GothenburgS-40530 GothenburgSweden University of Gothenburg

Purpose:Preserving and caring for nature in a sustainable way has long been part of Swedish preschool ***,recently has it been explicitly referenced in the Swedish preschool curriculum with the goal of incorporating sustainability holistically and coherently in all areas of children’s daily preschool experiences through play,care,and *** has revealed a potential roadblock to achieving this goal;the difficulty connecting the three inextricably linked dimensions of sustainability:ecological,social-cultural,and *** purpose is to generate knowledge about preschool teachers’professional understanding of education for sustainable development(ESD)in early childhood education(ECE)by implementing and enhancing the operationalization of such work in four Swedish ***/Approach/Methods:The design of the study rests on the involvement of teachers in work where they created sustainability activities supported by the Environmental Rating Scale for Sustainable Development in Early Childhood(ERS-SDEC).The data consist of teachers’narratives and interviews,and a qualitative content analysis is used from which a number of themes ***:The initial interviews foregrounded three themes:the value of collective resources,the wonders of nature,and a global *** the end of the project,the teachers’expressions of their practice revealed three qualitatively transformed themes:broadened awareness of sustainability,ecology embracing culture,and expanded perspectives,as factors of ***/Value:Teachers did increase their awareness of working with children and expressed a strength in using each other as collective *** that,their professional understandings of ESD in preschool developed.

关键词： Collective resources preschool education professional understanding sustainability

Histological assessment in peripheral nerve tissue engineering

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Neural Regeneration Research 2014年第18期9卷 1657-1660页

作者： Víctor Carriel ingrid Garzón Miguel Alaminos Maria Cornelissen Department of Histology (Tissue Engineering Group) Faculty of MedicineUniversity of Granadaand Instituto de Investigación Biosanitariaibs Department of Basic Medical Sciences (Histology and Tissue Engineering Group) Faculty of MedicineGhent University

The histological analysis of peripheral nerve regeneration is one of the most used methods to demonstrate the success of the regeneration through nerve conduits. Nowadays, it is possible to evaluate different parameters of nerve regeneration by using histological, histochemical, immunohistochemical and ultrastructural techniques. The histochemical methods are very sensible and are useful tools to evaluate the extracellular matrix remodeling and the myelin sheath, but they are poorly specific. In contrast, the immunohistochemical methods are highly specific and are frequently used for the identification of the regenerated axons, Sehwann cells and proteins associated to nerve regeneration or neural linage. The ultrastructural techniques offer the possibility to perform a high resolution morphological and quantitative analysis of the nerve regeneration. However, the use of a single histological method may not be enough to assess the degree of regeneration, and the combination of different histological techniques could be necessary.

关键词： peripheral nerve regeneration histology, histochemistry immunohistochemistry quantitative histology

RECTANGLE: a bit-slice lightweight block cipher suitable for multiple platforms

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Science China(Information Sciences) 2015年第12期58卷 89-103页

作者： ZHANG WenTao BAO ZhenZhen LIN DongDai Vincent RIJMEN YANG Bo Han ingrid VERBAUWHEDE State Key Laboratory of Information Security Institute of Information EngineeringChinese Academy of Sciences Department of Electrical Engineering ESAT COSIC and i Minds Security Department

In this paper, we propose a new lightweight block cipher named RECTANGLE. The main idea of the design of RECTANGLE is to allow lightweight and fast implementations using bit-slice techniques. RECTANGLE uses an SP-network. The substitution layer consists of 16 4 × 4 S-boxes in parallel. The permutation layer is composed of 3 rotations. As shown in this paper, RECTANGLE offers great performance in both hardware and software environment, which provides enough flexibility for different application scenario. The following are3 main advantages of RECTANGLE. First, RECTANGLE is extremely hardware-friendly. For the 80-bit key version, a one-cycle-per-round parallel implementation only needs 1600 gates for a throughput of 246 Kbits/s at100 k Hz clock and an energy efficiency of 3.0 p J/bit. Second, RECTANGLE achieves a very competitive software speed among the existing lightweight block ciphers due to its bit-slice style. Using 128-bit SSE instructions,a bit-slice implementation of RECTANGLE reaches an average encryption speed of about 3.9 cycles/byte for messages around 3000 bytes. Last but not least, we propose new design criteria for the RECTANGLE *** to our careful selection of the S-box and the asymmetric design of the permutation layer, RECTANGLE achieves a very good security-performance tradeoff. Our extensive and deep security analysis shows that the highest number of rounds that we can attack, is 18(out of 25).

关键词： lightweight cryptography block cipher design bit-slice hardware efficiency software efficiency

Effect of L-Arginine on Pulmonary Artery Smooth Muscle Cell Apoptosis in Rats with Hypoxic Pulmonary Vascular Structural Remodeling

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Acta Biochimica et Biophysica Sinica 2006年第1期38卷 15-21页

作者： ingrid Karmane SUMOU Beijing 100034.China Department of Pediatrics Peking University First Hospital

This study investigated the effect of L-arginine (L-Arg) on the apoptosis of pulmonary arterysmooth muscle cells (PASMC) in rats with hypoxic pulmonary vascular structural remodeling,and *** Wistar rats were randomly divided into a control group (n=5),a hypoxia group(n=7),and a hypoxia+L-Arg group (n=5).The morphologic changes of lung tissues were observed underoptical *** the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling assay,the apoptosis of PASMC was *** expression in PASMC wasexamined using *** results showed that the percentage of muscularized artery insmall pulmonary vessels,and the relative medial thickness and relative medial area of the small and medianpulmonary muscularized arteries in the hypoxic group were all significantly *** vascularstructural remodeling developed after *** smooth muscle cells of the small and median pul-monary arteries in the hypoxia group were significantly less than those in the control *** 14 d ofhypoxia,Fas expression by smooth muscle cells of median and small pulmonary arteries was significantlyinhibited.L-Arg significantly inhibited hypoxic pulmonary vascular structural remodeling in association withan augmentation of apoptosis of smooth muscle cells as well as Fas expression in *** resultsshowed that L-Arg could play an important role in attenuating hypoxic pulmonary vascular structural remod-eling by upregulating Fas expression in PASMC,thus promoting the apoptosis of PASMC.

关键词： hypoxia pulmonary artery arginine apoptosis

De novo serine synthesis regulates chondrocyte proliferation during bone development and repair

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Bone Research 2022年第2期10卷 274-285页

作者： Steve Stegen Shauni Loopmans ingrid Stockmans Karen Moermans Peter Carmeliet Geert Carmeliet Laboratory of Clinical and Experimental Endocrinology Department of Chronic Diseases and MetabolismKU Leuven3000 LeuvenBelgium Laboratory of Angiogenesis and Vascular Metabolism VIB Center for Cancer Biology3000 LeuvenBelgium Laboratory of Angiogenesis and Vascular Metabolism Department of Oncology and Leuven Cancer InstituteKU Leuven3000 LeuvenBelgium State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-Sen UniversityGuangzhou 510080China

The majority of the mammalian skeleton is formed through endochondral ossification starting from a cartilaginous *** cells, or chondrocytes, survive, proliferate and synthesize extracellular matrix in an avascular environment, but the metabolic requirements for these anabolic processes are not fully understood. Here, using metabolomics analysis and genetic in vivo models, we show that maintaining intracellular serine homeostasis is essential for chondrocyte function. De novo serine synthesis through phosphoglycerate dehydrogenase(PHGDH)-mediated glucose metabolism generates nucleotides that are necessary for chondrocyte proliferation and long bone growth. On the other hand, dietary serine is less crucial during endochondral bone formation, as serine-starved chondrocytes compensate by inducing PHGDH-mediated serine ***, this metabolic flexibility requires ATF4, a transcriptional regulator of amino acid metabolism and stress *** demonstrate that both serine deprivation and PHGDH inactivation enhance ATF4 signaling to stimulate de novo serine synthesis and serine uptake, respectively, and thereby prevent intracellular serine depletion and chondrocyte dysfunction. A similar metabolic adaptability between serine uptake and de novo synthesis is observed in the cartilage callus during fracture ***, the results of this study reveal a critical role for PHGDH-dependent serine synthesis in maintaining intracellular serine levels under physiological and serine-limited conditions, as adequate serine levels are necessary to support chondrocyte proliferation during endochondral ossification.

关键词： synthesis starting thereby