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Campaign-style U-Pb titanite petrochronology:Along-strike variations in timing of metamorphism in the Himalayan metamorphic core

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Geoscience Frontiers 2019年第3期10卷 827-847页

作者： Catherine m.mottram john m.Cottle Andrew R.C.Kylander-Clark School of Earth and Environmental Sciences University of Portsmouth Department of Earth Science University of CaliforniaSanta Barbara

Present-day along-strike heterogeneities within the Himalayan orogen are seen at many scales, from variations within the deep architecture of the lithospheric mantle, to differences in geomorphologic surface processes. Here, we present an internally consistent petrochronologic dataset from the Himalayan metamorphic core(HmC), in order to document and investigate the causes of along-strike variations in its Oligocene-miocene tectonic history. Laser ablation split-stream analysis was used to date and characterise the geochemistry of titanite from 47 calc-silicate rocks across >2000 km along the *** combined U-Pb-REE-Zr single mineral dataset circumvents uncertainties associated with interpretations based on data compilations from different studies, mineral systems and laboratories, and allows for direct along-strike comparisons in the timing of metamorphic processes. Titanite dates range from ～30 ma to 12 ma, recording(re-)crystallization between 625 ℃ and 815 ℃. Titanite T-t data overlap with previously published P-T-t paths from interleaved peltic rocks, demonstrating the usefulness of titanite petrochronology for recording the metamorphic history in lithologies not traditionally used for thermobarometry. Overall, the data indicate a broad eastward-younging trend along the *** in the duration and timing of metamorphism within the HmC are best explained by alongstrike variations in the position of ramps on the basal detachment controlling a two-stage process of preferential ductile accretion at depth followed by the formation of later upper-crust brittle *** processes, coupled with variable erosion, resulted in the asymmetric exhumation of a younger,thicker crystalline core in the eastern Himalaya.

关键词： Himalaya Petrochronology Titanite metamorphic petrology

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mixing of powders and granular materials by mechanical means——A perspective

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Particuology 2012年第4期10卷 397-427页

作者： john Bridgwater Department of Chemical Engineering and Biotechnology University of CambridgePembroke StreetCambridge CB2 3RAUK Laboratory for Simulation and modeling of Particulate Systems School of Materials Science and EngineeringThe University of New South WalesSydneyNSW 2052Australia

When engineers and scientists encounter the mixing of powders, they enter a subject where it is often difficult to find bearings. This perspective seeks to address this need by setting out the state of prac- tice. It then considers the growing momentum in the area following advances in computation and in measurement that became significant in the 1990s. The mixing of powders and granular materials is of central importance for the quality and performance of a wide range of products. However, process design and operation are very difficult, being largely based on judgement rather than science. There are not even tabulated data to tell how the quality of mixtures depends on mixer selection. Design depends on experience and insight, not science. There are no sound scale-up laws for a given equipment type, largely because particle size needs to be included in any dimensional analysis. Design is not possible by applying physical principles. There is no reliable equation to describe the flow of single component powders, let alone multi-component mixtures. In most cases, measurement has been difficult because the materials are optically opaque. Work in the research literature has been questionable because the results obtained for mixture sampling are affected by sample size. Recently, modern experimental techniques and modelling work have provided a good deal of infor- mation on the behaviour of many of the pieces of equipment, though these have been small in size and often confined to materials of a single size. However, the studies have enhanced knowledge of physical behaviour. For example, for a wide range of equipment when operating at lower velocities, mixing is determined by the number of revolutions of the mixer, not the time. Observations of flow structure have led to a few specific models that should scale with equipment size. measurement techniques are slowly becoming more effective in giving internal flow patterns and in measuring powder composition. For cohe

关键词： PerspectivePowder mixingmixing of granular materialsCurrent designmixture qualitymixing mechanismsExperiments and computationsResearch trendsOpportunities for advanceSegregationCohesion

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Intermediate hyperglycemia in early pregnancy:A South Asian perspective

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World Journal of Diabetes 2023年第5期14卷 573-584页

作者： john Punnose Komal Sukhija Rashika m Rijhwani Department of Endocrinology and metabolism St.Stephen’s HospitalDelhi 110054India Department of Endocrinology St.Stephen’s HospitalDelhi 110054India

“Intermediate hyperglycemia in early pregnancy(IHEP)”refers to mild hyperglycemia detected before 24 gestational weeks(GW),satisfying the criteria for the diagnosis of gestational diabetes *** professional bodies recommend routine screening for“overt diabetes”in early pregnancy,which identifies a significant number of women with mild hyperglycemia of undetermined significance.A literature search revealed that one-third of GDm women in South Asian countries are diagnosed before the conventional screening period of 24 GW to 28 GW;hence,they belong in the IHEP *** hospitals in this region diagnose IHEP by oral glucose tolerance test(OGTT)using the same criteria used for GDm diagnosis after 24 *** is some evidence to suggest that South Asian women with IHEP are more prone to adverse pregnancy events than women with a diagnosis of GDm after 24 GW,but this observation needs to be proven by randomized control *** plasma glucose is a reliable screening test for GDm that can obviate the need for OGTT for GDm diagnosis among 50%of South Asian pregnant ***1c in the first trimester predicts GDm in later pregnancy,but it is not a reliable test for IHEP *** is evidence to suggest that HbA1c in the first trimester is an independent risk factor for several adverse pregnancy *** research to identify the pathogenetic mechanisms behind the fetal and maternal effects of IHEP is strongly recommended.

关键词： Intermediate hyperglycemia Early pregnancy Gestational diabetes South Asian women Adverse events Asian Indian

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The 12th International Symposium on Spermatology

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Asian Journal of Andrology 2015年第4期17卷 519-520页

作者： R john Aitken Jim m Cummins Brett Nixon Priority Research Centre in Reproductive Science Discipline of Biological Sciences and HunterMedical Research Institute University of NewcastleNSW 2308 Australia Division of Veterinary andBiomedical Sciences Murdoch University MurdochWA. Australia.

The 12th International Symposium of Spermatology continued the excellent tradition of this meeting since its inception in 1969 when the first Symposium was held in Italy under the Chairmanship of Professor Baccio Baccetti. This unique Symposium is held every 4 years and serves as a beacon for sperm cell biologists from all over the world, regardless of which species, animal or plant, they are working on. This willingness to embrace the fundamental biology of this distinctive cell type without species limitations is one of the hallmarks of this Symposium. For sperm biologists - it is our Olympics. The meeting in Newcastle, NSW brought together around 300 biologists from more than 22 different countries covering North and South America, Africa, Europe, Asia and Australia. Given the considerable distances and high cost involved in travelling to the East Coast of NSW, this was an outstanding outcome. The Symposium featured a series of 31 plenary lectures culminating in the prestigious Thaddeus mann memorial Lecture, which was delivered with typical grace and brilliance by Professor masaru Okabe.

关键词： International Symposium Spermatology

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Genetic variability of the stable fly assessed on a global scale using amplified fragment length polymorphism

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Insect Science 2016年第5期23卷 695-703页

作者： Kathleen m Kneeland Steven R. Skoda john E. Foster Department of Entomology 103 Entomology Haft University of Nebraska-Lincoln Lincoln NE 68583 USDA-ARS-KBUSLIRL Screwworm Research Unit 2700 Fredericksburg Road Kern/ille TX 78028 USA

The stable fly, Stomoxys calcitrans （L.）（Diptera： muscidae）, is a blood-feeding, economically important pest of animals and humans worldwide. Improved management strategies are essential and their development would benefit from studies on genetic di- versity of stable flies. Especially if done on a global scale, such research could generate information necessary for the development and application of more efficient control meth- ods. Herein we report on a genetic study of stable flies using amplified fragment length polymorphism, with samples of 10-40 individuals acquired from a total of 25 locations in the Nearctic, Neotropic, Palearctic, Afrotropic and Australasian biogeographical regions. We hypothesized that genetic differentiation would exist across geographical barriers. Although Fsx （0.33） was moderately high, the Gsx （0.05; representing genetic diversity between individuals） was very low; Nm values （representing gene flow） were high （9.36）. The mismatch distribution and tests of neutrality suggested population expansion, with no genetic differentiation between locations. The analysis of molecular variance （AmOVA） results showed the majority of genetic diversity was within groups. The mantel test showed no correlation between geographic and genetic distance; this strongly supports the AmOVA results. These results suggest that stable flies did not show genetic differentiation but are panmictic, with no evidence of isolation by distance or across geographical barriers.

关键词： AFLP biting flies external parasites genetic diversity livestock pests Stomoxys calcitrans

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Immunotherapy of gastric cancer:Present status and future perspectives

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World Journal of Gastroenterology 2024年第8期30卷 779-793页

作者： john K Triantafillidis manousos m Konstadoulakis Apostolos E Papalois Inflammatory Bowel Disease Unit “Metropolitan General”HospitalHolargos 15562AtticaGreece.Hellenic Society for Gastrointestinal Oncology354 Iera OdosChaidari 12461AtticaGreece Second Department of Surgery University of Athens School of MedicineAretaieion HospitalAthens 11528AtticaGreece Unit of Surgical Research and Training Second Department of SurgeryUniversity of AthensSchool of MedicineAretaieion HospitalAthens 11528AtticaGreece

In this editorial,we comment on the article entitled“Advances and key focus areas in gastric cancer immunotherapy:A comprehensive scientometric and clinical trial review(1999-2023),”which was published in the recent issue of the World Journal of *** focused on the results of the authors’bibliometric analysis concerning gastric cancer immunotherapy,which they analyzed in depth by compiling the relevant publications of the last 20 *** that,we briefly describe the most recent data concerning the epidemiological parameters of gastric cancer(GC)in different countries,attempting to give an interpretation based on the etiological factors involved in the etiopathogenesis of the *** then briefly discuss the conservative treatment(chemotherapy)of the various forms of this malignant *** describe the treatment of resectable tumors,locally advanced neoplasms,and unresectable(advanced)*** attention is given to modern therapeutic approaches with emphasis on immunotherapy,which seems to be the future of GC treatment,especially in combination with *** is also a thorough analysis of the results of the study under review in terms of the number of scientific publications,the countries in which the studies were conducted,the authors,and the scientific centers of origin,as well as the clinical studies in ***,an attempt is made to draw some conclusions and to point out possible future directions.

关键词： Gastric cancer Chemotherapy Immunotherapy Immune checkpoint inhibitors Bibliometrics Scientometrics

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Inflammation-associated microsatellite alterations:mechanisms and significance in the prognosis of patients with colorectal cancer

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World Journal of Gastrointestinal Oncology 2018年第1期10卷 1-14页

作者： minoru Koi Stephanie S Tseng-Rogenski john m Carethers Department of Internal medicine and Comprehensive Cancer Center University of MichiganAnn ArborMI 48109-5368United States

microsatellite alterations within genomic DNA frameshift as a result of defective DNA mismatch repair(mmR). About 15% of sporadic colorectal cancers(CRCs) manifest hypermethylation of the DNA mmR gene mLH1, resulting in mono-and di-nucleotide frameshifts to classify it as microsatellite instability-high(mSI-H) and hypermutated, and due to frameshifts at coding microsatellites generating neo-antigens, produce a robust protective immune response that can be enhanced with immune checkpoint blockade. more commonly, approximately 50% of sporadic nonmSI-H CRCs demonstrate frameshifts at di-and tetra-nucleotide microsatellites to classify it as mSIlow/elevated microsatellite alterations at selected tetranucleotide repeats(EmAST) as a result of functional somatic inactivation of the DNA mmR protein mSH3 via a nuclear-to-cytosolic displacement. The trigger for mSH3 displacement appears to be inflammation and/or oxidative stress, and unlike mSI-H CRC patients, patients with mSI-L/EmAST CRCs show poor prognosis. These inflammatory-associated microsatellite alterations are a consequence of the local tumor microenvironment, and in theory, if the microenvironment is manipulated to lower inflammation, the microsatellite alterations and mSH3 dysfunction should be corrected. Here we describe the mechanisms and significance of inflammatory-associated microsatellite alterations, and propose three areas to deeply explore the consequences and prevention of inflammation's effect upon the DNA mmR system.

关键词： microsatellite instability microsatellite stable Elevated microsatellite alterations at selected tetranucleotide repeats Colorectal cancer mismatch repair Inflammation mSH3

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Convergence Properties of Local Defect Correction Algorithm for the Boundary Element method

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Computer modeling in Engineering & Sciences 2019年第4期119卷 207-225页

作者： Godwin Kakuba john m.mango martijn J.H.Anthonissen makerere University P.O.Box 7062KampalaUganda Eindhoven University of Technology P.O.Box 5135600 MB EindhovenThe Netherlands

Sometimes boundary value problems have isolated regions where the solution changes ***,when solving numerically,one needs a fine grid to capture the high *** fine grid can be implemented as a composite coarse-fine grid or as a global fine *** cheaper way of obtaining the composite grid solution is the use of the local defect correction *** technique is an algorithm that combines a global coarse grid solution and a local fine grid solution in an iterative way to estimate the solution on the corresponding composite *** algorithm is relatively new and its convergence properties have not been studied for the boundary element *** this paper the objective is to determine convergence properties of the algorithm for the boundary element ***,we formulate the algorithm as a fixed point iterative scheme,which has also not been done before for the boundary element method,and then study the properties of the iteration *** show that we can always expect ***,the algorithm opens up a real alternative for application in the boundary element method for problems with localised regions of high activity.

关键词： Local defect defect correction composite grids integral equation methods boundary elements

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Paleoproterozoic volcanic rocks in the southern margin of the North China Craton, central China:Implications for the Columbia supercontinent

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Geoscience Frontiers 2019年第4期10卷 1543-1560页

作者： Changming Wang Xinyu He Emmanuel john m. Carranza Chengmin Cui State Key Laboratory of Geological Processes and mineral Resources China University of GeosciencesBeijing 100083China Centre for Exploration Targeting University of Western AustraliaPerthWestern Australia 6009Australia China Non-ferrous metals Resource Geological Survey Beijing 100012China Discipline of Geological Sciences University of KwaZulu-NatalWestville CampusDurban 3629South Africa

The volcanic rocks of the Xiong’er Group are situated in the southern margin of the North China Craton(NCC).Research on the Xiong er Group is important to understand the tectonic evolution of the NCC and the Columbia supercontinent during the *** this study,to constrain the age of the Xiong’er volcanic rocks and identify its tectonic environment,we report zircon LA-ICP-mS data with Hf isotope,whole-rock major and trace element compositions and Sr-Nd-Pb-Hf isotopes of the volcanic rocks of the Xiong’er *** Xiong’er volcanic rocks mainly consist of basaltic andesite,*** and rhyolite,with minor *** new sets of data combined with those from previous studies indicate that Xiong’er volcanism should have lasted from 1827 ma to 1746 ma as the major phase of the *** volcanics have extremely low *** and Ni contents,are enriched in LREEs and LILEs but depleted in HFSEs(Nb,Ta,and Ti),similar to arc-related volcanic *** are characterized by negative zirconεHft values of-17.4 to 8.8,whole-rock initial 87Sr/86Sr values of 0.7023 to 0.7177 andεNd(t)values of-10.9 to *** Pb isotopes(206Pb/204Pb=14.366-16.431,207Pb/204Pb=15.106-15.371,208Pb/204Pb=32.455-37.422).The available elemental and Sr-Nd-Pb-Hf isotope data suggest that the Xiong’er volcanic rocks were sourced from a mantle contaminated by continental *** volcanic rocks of the Xiong’er Group might have been generated by high-degree partial melting of a lithospheric mantle that was originally modified by oceanic subduction in the ***,we suggest that the subduction-modified lithospheric mantle occurred in an extensional setting during the breakup of the Columbia supercontinent in the Late Paleoproterozoic,rather than in an arc setting.

关键词： Volcanic rocks Geochronology Sr-Nd-Pb-Hf isotopes Paleoproterozoic North China Craton Supercontinent Columbia

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Aerodynamics of a Tandem-Bladed Axial Compressor Rotor under Circumferential Distortion at Different Rotational Speeds

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Journal of Thermal Science 2024年第4期33卷 1340-1356页

作者： Amit KUmAR Jerry T.john A.m.PRADEEP R.A.DAKKERmANS Dragan KOZULOVIC Department of Aerospace Engineering Indian Institute of Technology BombayMumbai400076India Department of Automotive and Aeronautical Engineering Hamburg University of Applied Sciences20099HamburgGermany Institute of Jet Propulsion Bundeswehr University Munich85577NeubibergGermany

For most aircraft engines,inflow distortion is *** distortion is known to degrade the aerodynamic performance and stable operating limits of a *** rotor configuration is an arrangement that effectively controls the growth of the boundary layer over the suction surface of the ***,a higher total pressure rise can be achieved through this unconventional design approach involving the splitting of the blade into forward and aft *** is expected that the effect of inlet flow distortion would be more severe for a tandem-rotor design due to the greater flow turning inherent in such ***,this aspect needs to be thoroughly *** present study discusses the effect of circumferential distortion on the tandem-rotor at different rotational ***-annulus RANS simulations using ANSYS CFX are used in the present *** performance of the rotor at a particular flow coefficient and different rotational speeds is *** total pressure and efficiency are observed to drop at lower mass flow rates under the influence of circumferential *** loss region in each blade passage is mainly associated with the blade wake,tip leakage vortex,secondary flow,and boundary ***,their contribution varies from passage to passage,particularly in the distorted *** the lower span,the wake width is found to be higher than that at a higher *** to the redistribution of the mass flow,the circumferential extent reduces at a higher *** the undistorted sector,the strength of the tip leakage vortex is significantly higher at the design rotational speed than at lower *** distortion near the tip region promotes an early vortex breakdown even at the design operating *** adversely affects the total pressure,efficiency,and stall *** clean flow conditions,this phenomenon is only observed near the stall *** the design operating condition,the breakdown of the forward rotor tip l

关键词： tandem rotor circumferential distortion loss tip leakage vortex vortex breakdown diffusion factor aerodynamics of compressor blade

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