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Deciphering fluid inclusions in high-grade rocks

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Geoscience Frontiers 2014年第5期5卷 683-695页

作者： Alfons van den Kerkhof Andreas Kronz Klaus simon Geowissenschaftliches Zentrum der Universitat Gottingen Goldschmidtstr.1-3 D 37073 GottingenGermany

The study of fluid inclusions in high-grade rocks is especially challenging as the host minerals have been normally subjected to deformation, recrystallization and fluid-rock interaction so that primary in- clusions, formed at the peak of metamorphism are rare. The larger part of the fluid inclusions found in metamorphic minerals is typically modified during uplift. These late processes may strongly disguise the characteristics of the ＂original＂ peak metamorphic fluid. A detailed microstructural analysis of the host minerals, notably quartz, is therefore indispensable for a proper interpretation of fluid inclusions. Cathodoluminescence （CL） techniques combined with trace element analysis of quartz （ePMA, LA- [CPMS） have shown to be very helpful in deciphering the rock-fluid evolution. Whereas high-grade metamorphic quartz may have relatively high contents of trace elements like Ti and A1, low- temperature re-equilibrated quartz typically shows reduced trace element concentrations. The result- ing microstructures in CL can be basically distinguished in diffusion patterns （along microfractures and grain boundaries）, and secondary quartz formed by dissolution-reprecipitation. Most of these textures are formed during retrograde fluid-controlled processes between ca. 220 and 500 ℃, i.e. the range of semi-brittle deformation （greenschist-facies） and can be correlated with the fluid inclusions. In this way modified and re-trapped fluids can be identified, even when there are no optical features observed under the microscope.

关键词： Fluid inclusionsGranuliteCharnockiteCathodoluminescenceLA-ICPMSQuartz

Astrophysical constraints on the proton-to-electron mass ratio with FAST

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Research in Astronomy and Astrophysics 2019年第2期19卷 15-24页

作者： Xi Chen simon P.ellingsen Ying Mei Center for Astrophysics Guangzhou University Shanghai Astronomical Observatory Chinese Academy of Sciences School of Physical Sciences University of Tasmania

That the laws of physics are the same at all times and places throughout the Universe is one of the basic assumptions of physics. Astronomical observations provide the only means to test this basic assumption on cosmological time and distance scales. The possibility of variations in the dimensionless physical constant μ-the proton-to-electron mass ratio, can be tested by comparing astronomical measurements of the rest frequency of certain spectral lines at radio wavelengths with laboratory determinations. Different types of molecular transitions have different dependencies on μ and so observations of two or more spectral lines towards the same astronomical source can be used to test whether there is any evidence for either temporal or spatial changes in the physical fundamental constants. μ will change if the relative strength of the strong nuclear force compared to the electromagnetic force varies. Theoretical studies have shown that the rotational transitions of some molecules which have transitions in the frequency range that will be covered by FAST(e.g., CH_3 OH, OH and CH) are sensitive to changes in μ. A number of studies looking for possible variations in μ have been undertaken with existing telescopes, however, the greater sensitivity of FAST means it will open new opportunities to significantly improve upon measurements made to *** this paper, we discuss which molecular transitions and sources(both in the Galaxy and external galaxies)are likely targets for providing improved constraints on μ with FAST.

关键词： ISM:molecules radio lines:ISM techniques:radial velocities elementary particles

Fast-moving target tracking based on mean shift and frame-difference methods

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Journal of Systems engineering and electronics 2011年第4期22卷 587-592页

作者： Hongpeng Yin Yi Chai simon X. Yang Xiaoyan Yang College of Automation Chongqing University Chongqing 400044 E R. China State Key Laboratory of Power Transmission equipment & System Security and New Technology College of Automation Chongqing University Chongqing 400044 P. R. China School of engineering University of Guelph Guelph N1G 2W1 Canada

The mean shift tracker has difficulty in tracking fast moving targets and suffers from tracking error accumulation problem. To overcome the limitations of the mean shift method, a new approach is proposed by integrating the mean shift algorithm and frame-difference methods. The rough position of the moving tar- get is first located by the direct frame-difference algorithm and three-frame-difference algorithm for the immobile camera scenes and mobile camera scenes, respectively. Then, the mean shift algorithm is used to achieve precise tracking of the target. Several tracking experiments show that the proposed method can effectively track first moving targets and overcome the tracking error accumulation problem.

关键词： mean shift frame-difference method target tracking,computer vision.

Applications of Graph Theory to Gross error Detection for GPS Geodetic Control Networks

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Geo-Spatial Information Science 2002年第4期5卷 26-31页

作者： Samwel simon Katambi Land Department Njomce-Iriga Tanzania

This paper describes a broad perspective of the application of graph theory to establishment of GPS control networks whereby the GPS network is considered as a connected and directed graph with three *** this algorithm the gross error detection is undertaken through loops of different spanning trees using the "Loop Law" in which the individual components Δ X, Δ Y and Δ Z sum up to *** the sum of the respective vector components ∑X,∑Y and ∑Z in a loop is not zero and if the error is beyond the tolerable limit (ε>w),it indicates the existence of gross errors in one of the baselines in the loop and therefore the baseline must be removed or re_*** successful screening of errors by graph theory,network adjustment can be carried *** this paper,the GPS data from the control network established as reference system for the HP Dam at Baishan county in Liaoning province is presented to illustrate the algorithm.

关键词： GPS control network quality criteria graph theory directed graph spanning tree fundamental loop incident matrix gross error

Bone loss from Wnt inhibition mitigated by concurrent alendronate therapy

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Bone Research 2018年第2期6卷 167-176页

作者： Babita Madan Mitchell J.McDonald Gabrielle e.Foxa Cassandra R.Diegel Bart O.williams David M.Virshup Program in Cancer and Stem Cell Biology Duke-NUS Medical School Center for Cancer and Cell Biology and Program for Skeletal Disease and Tumor Microenvironment Van Andel Research Institute Department of Pediatrics Duke University

Dysregulated Wnt signaling is associated with the pathogenesis of cancers, fibrosis, and vascular diseases. Inhibition of Wnt signaling has shown efficacy in various pre-clinical models of these disorders. One of the key challenges in developing targeted anti-cancer drugs is to balance efficacy with on-target toxicity. Given the crucial role Wnts play in the differentiation of osteoblasts and osteoclasts, acute inhibition of Wnt signaling is likely to affect bone homeostasis. In this study, we evaluated the skeletal effect of small molecule inhibitor of an o-acyl transferase porcupine（PORCN） that prevents Wnt signaling by blocking the secretion of all Wnts. Micro-computed tomography and histomorphometric evaluation revealed that the bones of mice treated with two structurally distinct PORCN inhibitors LGK974 and eTC-1922159（eTC-159） had loss-of-bone volume and density within 4 weeks of exposure. This decreased bone mass was associated with a significant increase in adipocytes within the bone marrow. Notably,simultaneous administration of a clinically approved anti-resorptive, alendronate, a member of the bisphosphonate family,mitigated loss-of-bone mass seen upon eTC-159 treatment by regulating activity of osteoclasts and blocking accumulation of bone marrow adipocytes. Our results support the addition of bone protective agents when treating patients with PORCN *** of bone toxicity can extend the therapeutic utility of Wnt pathway inhibitors.

关键词： Wnt eTC Bone loss Wnt inhibition mitigated concurrent alendronate therapy

Settling,consolidation and shear strength behaviour of coal tailings slurry

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International Journal of Mining Science and Technology 2020年第6期30卷 849-857页

作者： Shriful Islam David J.williams Marcelo Llano-Serna Chenming Zhang School of Civil engineering The University of QueenslandQueensland 4072Australia Department of Civil and environmental engineering Shahjalal University of Science and TechnologySylhet 3114Bangladesh Geotechnical engineer Klohn Crippen Berger Ltd.Queensland 4101Australia

The volume change and shear strength behaviour of tailings slurry with the changes in gravimetric moisture content is important to effectively utilise the storage volume and analysis of dam failure *** testing of tailings from a slurry-like to soil-like state is a critical task,and conventional consolidation apparatus does not have the capability of doing such testing,as the tailings slurries contain high water *** tests conducted on slurries having a 25%solids concentration showed very low efficiency;final sediment was still *** intrinsic point was identified based on pore water pressure dissipation during consolidation tests in a slurry consolidometer that can define two states of the tailings ***-like and *** the slurry-like state,the volume change was greater for Slurry 2 than Slurry 1,while the inverse was observed in the soil-like *** evolution of peak vane shear strength with the changes in moisture content was almost similar for both samples and obeyed the power *** models have been developed and validated to predict the shear strength of materials at any gravimetric moisture content or void ratio.

关键词： Settling Consolidation Vane shear strength Coal tailings slurry Slurry consolidometer

Anticoagulation in frail older people

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Journal of Geriatric Cardiology 2019年第11期16卷 844-846页

作者： Sarah Damanti simon Braham Luca Pasina Geriatric Unit IRCCS Ca’Granda Ospedale Maggiore PoliclinicoMilanItaly Nutritional Sciences PhD Univeristy of MilanMilanItaly Angelo Bianchi Bonomi Hemophilia and Thrombosis Center IRCCS CàGranda Maggiore Hospital FoundationMilanItaly Pharmacotherapy and Appropriateness of Drug Prescription Unit Istituto Di Ricerche Farmacologiche Mario Negri IRCCSVia Giuseppe La MasaMilanItaly

Frailty is a multidimensional dynamic condition characterized by decreased physiological reserves. Therefore,frail people are more vulnerable to ***,minor stimuli,like a new drug prescription,can alter their homeostatic equilibrium determining adverse clinical outcomes(i.e.,falls,institutionalization,disability,and death).[1,2]Since the risk of atrial fibrillation[3]and venous thromboembolism[4]increase with ageing,frail people might require long term anticoagulation.

关键词： Anticoagulation Frailty The elderly

Numerical simulations of water flow and contaminants transport near mining wastes disposed in a fractured rock mass

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International Journal of Mining Science and Technology 2015年第1期25卷 37-45页

作者： Ben Abdelghani Farouk Aubertin Michel simon Richard Therrien René Department of Civil engineering Institut Supérieur de la Construction et de l’Urbanisme Research Institute on Mines and the environment (RIMe) Polytechnique Montreal Department of Geology and Geological engineering University Laval

A numerical tool, called Hydro-Geosphere, was used to simulate unsaturated water flow and contaminants migration around an open pit filled with mining wastes. Numerical simulations had been carried out to assess the influence of various factors on water flow and solute transport in and around the surface openings including recharge, properties of the waste material and presence of fractures in the surrounding rock mass. The effect of the regional hydraulic gradient was also investigated. The analyses were conducted by simulating various 2D cases using experimentally obtained material properties and controlled boundary conditions. The effects of the hydrogeological properties of the filling material(i.e., water retention curve and hydraulic conductivity function), fracture network characteristics and conductivity of the joints were assessed. The results illustrate that fractures control water flow and contaminants transport around the waste disposal area. A fracture network can desaturate the system and improve the regional gradient effect.

关键词： Hydro-GeosphereNumerical modellingUnsaturated water flowContaminants transportTailingsWaste rocks

Stone-scoring systems for predicting complications in percutaneous nephrolithotomy:A systematic review of the literature

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Asian Journal of Urology 2023年第3期10卷 226-238页

作者： Giorgio Mazzon simon Choong Antonio Celia Department of Urology AULSS7 PedemontanaSan Bassiano HospitalBassano Del GrappaItaly Institute of Urology University College Hospitals of LondonLondonUK

Objective:Percutaneous nephrolithotomy is a treatment of choice for larger stones of the upper urinary ***,several nephrolithometric nomograms for prediction of post-operative surgical outcomes have been proposed,although uncertainties still exist regarding their roles in the estimation of ***:We conducted a systematic review on PubMed and Web of Sciences databases including english studies with at least 100 cases and published between January 2010 and December *** identified original articles evaluating correlations between the Guy’s stone score,the stone size(S),tract length(T),obstruction(O),number of involved calices(N),and essence or stone density(e)(S.T.O.N.e.),Clinical Research Office of the endourological Society(CROeS),and Seoul National University Renal Stone Complexity(S-ReSC)scores and post-operative complications in adult *** also included newly designed nomograms for prediction of specific ***:After an initial search of 549 abstracts,we finally included a total of 18 *** them,11 investigated traditional nephrolithometric nomograms,while seven newly designed nomograms were used to predict specific ***,7316 patients have been *** total,14 out of 18 papers are derived from retrospective single-center ***’s stone score obtained correlation with complications in five,*** score in four,while CROeS score and S-ReSC score in three and two,*** of the studies investigated minimally invasive percutaneous nephrolithotomy(PCNL)and all cases have been conducted in prone *** newly designed nomograms,none of them is currently externally validated;five of them predict post-operative infections;the remaining two have been designed for thromboembolic events and urinary ***:This review presents all nomograms currently available in the PCNL field and highlights a certain number of *** data ha

关键词： Percutaneous nephrolithotomy Complications Nomogram Stone-scoring system Clavien-Dindo