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Convergent plate boundary environments for formation of≥3800 Ma mafic-ultramafic assemblages(Isua area,Greenland):Implications for early global geodynamics

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Geoscience Frontiers 2024年第3期15卷 119-136页

作者： Allen p.Nutman Clark R.L.Friend Vickie C.Bennett School of Earth Atmospheric and Life SciencesUniversity of WollongongWollongongNSW 2522Australia Glendale TiddingtonOxon OX92LQUK Research School of Earth Sciences Australian National UniversityCanberraACT 2601Australia

In the gneiss terrane on the south side of the Eoarchean Isua supracrustal belt,ultramafic rocks with relict abyssal peridotite mineralogy(Bennett et al.,2002;Friend et al.,2002;Nutman et al.,2007;Rollinson,2007;van de Löcht et al.,2020),layered gabbros with cumulate ultramafic rocks,basalts and associated siliceous sedimentary rocks were tectonically-imbricated,prior to and during intrusion of ca.3800 Ma *** with3800 Ma basalts in the Outer Arc Group of the nearby Isua supracrustal belt,the composition of all these mafic rocks(e.g.,Th-Hf-nb systematics,high Th/Yb,Ba/nb,Ba/Yb ratios and negative nb and Ti anomalies)shows affinity with modern suprasubduction rocks whose genesis involved fluid fluxing of the upper ***,the majority of these samples have Ba/nb and Ba/Yb values less than in modern island arc magmas,but similar to many backarc basin magmas(e.g.,pearce and Stern,2006).It is unknown whether these ca.3800 Ma mafic rocks are,(i)arc rocks where the Ba/nb and Ba/Yb signatures reflect lower surficial Ba in Eoarchean oceanic settings,or(ii)in direct comparison with phanerozoic suites,these signatures reflect a back-arc setting with interplay between fluid fluxing and decompressional *** tectonic intercalation of upper mantle with lower and upper crustal rocks,combined with the fluid-fluxing influences seen in chemistry of all the mafic rocks is best accommodated in a compressional Eoarchean convergent plate boundary setting within a mobile-lid *** stagnant lid scenarios of crust formation,if operative,must have co-existed or alternated with mobile-lid regimes by 3800 Ma.

关键词： Eoarchean Fluid-fluxing plate tectonics Suprasubduction Crustal evolution

Advanced approach for antifungal susceptibility and characterization of resistance properties in clinical and environmental isolates of Cryptococcus species complex

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Infectious Medicine 2022年第3期1卷 147-153页

作者： Shayanki Lahiri Nagarathna chandrashekar Department of Neuromicrobiology National Institute of Mental Health and Neuro SciencesBangaloreKarnatakaIndia Department of Computational Medicine and Bioinformatics University of MichiganAnn ArborUSA

Background:Meningitis due to Cryptococcus neoformans/gattii is a fatal infection affecting immunocompromised population *** B(AmB),fluconazole(FLC)and 5-flucytosine are the drugs of choice to treat the *** studied antifungal susceptibility pattern of clinical and environmental cryptococcal species using newer approach and analyze their resistant ***:Eighty clinical(54 *** and 26 ***)and 18 environmental(14 *** and 4 ***)isolates were subjected to antifungal susceptibility testing by automated(VITEK2C)*** inhibitory concentrations(MIC)were analyzed *** DNA of FLC resistant isolates was extracted and amplified to detect presence of CnAFR1 ***:*** showed 1.85%and 21.4%AmB resistance,and 1.85%and 28.5%FLC-resistance,whereas *** showed 25%and 50%FLC-resistance among clinical and environmental isolates *** values were significantly(pphylogenetic relationship among the resistant ***:This pioneering study provides an insight into the sensitivity patterns of clinical and environmental cryptococcal isolates from south *** recent emergence of AmB-resistance may transpire as a challenge for the *** the clinical and environmental isolates are phylogenetically evolved from CnAFR1 gene of Filobasidiella neoformans,the resistance is most probably an inherent *** study emphasizes the need for speciation and antifungal susceptibility testing of cryptococcal isolates from clinical sources to institute appropriate antifungal therapy and to reduce the mortality and morbidity.

关键词： Cryptococcus neoformans/gattii Environmental isolates Clinical isolates Antifungal susceptibility CnAFR1 Amphotericin B resistance

Seasonal changes in Hermit Thrush (Catharus guttatus) song syntax

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Avian Research 2024年第2期15卷 172-179页

作者： Sean p.Roach Luke C.McLean Jeff W.MacLeod Leslie S.phillmore psychology Department University of New Brunswick Saint John100 Tucker Park RoadSaint JohnNBCanada Department of psychology and Neuroscience Dalhousie University1355 Oxford StHalifaxNSB3H 4J1Canada

In many songbird species,birdsong features phonological syntax,meaning that the units within their vocal se-quences are ordered in a non-random way that adheres to a *** such syntactical patterns have been richly described in many species,comparatively little is known about how those patterns contribute to song achieving its important *** each of song’s main functions,territorial defense and mate attraction,evidence of a role for syntax is *** species for which syntax has been thoroughly described is the Hermit Thrush(Catharus guttatus),which presents song types from their repertoires in a semi-predictable order and,in doing so,rapidly cycle up and down the frequency *** objective of the present study was to explore the importance of song syntax in the Hermit Thrush through a within-subject examination of how measures of syntax,such as the predictability of song type order within song sequences,shift over the breeding *** hypothesized that,if such syntactical characteristics are important to breeding behaviour,they would be most prominent at the start of the breeding season when activity associated with territory establishment and mate attraction is most *** revealed that,as predicted,the rigidness of song type ordering within se-quences was highest at the start of the season and declined *** song type sequences were most predictable at the vitally important early part of the breeding season fit our hypothesis that this aspect of song syntax is important to song’s functions related to territory establishment and/or mate *** work will clarify whether that role relates to one of song’s two main functions or serves song transmission in some broader way.

关键词： Birdsong Hermit Thrush Seasonal change Stereotypy Syntax

Role of Heat Treatment on Al6061- Frit particulate Composites

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Journal of Minerals and Materials Characterization and Engineering 2012年第4期11卷 353-363页

作者： D. Ramesh R.p. Swamy T.K. chandrashekar Department of Mechanical Engineering Sri Siddhartha Institute of Technology Tumkur-572105 India Department of studies in Mechanical Engineering University B.D.T. College of Engineering Davangere-577004 India Research scholar Sri Siddhartha Institute of Technology Tumkur-572105 India

In recent decades, aluminium alloy based metal matrix composites are used in several applications. Al6061 has been used as matrix material due to its good formability, excellent mechanical properties and etc., wide spectrum of the applications in industrial sectors. Inclusion of Frit particulates as reinforcement in Al6061 alloy material system improves its hardness and decrease in density. In the present investigation Al6061-Frit particulate composites were produced by ‘VORTEX’ method with varying weight percentages of Frit particulate from 0 wt% to 10 wt% in steps of *** as cast matrix alloy and its composites have been subjected to solutionizing treatment at a temperature of 530℃ for 2 hours followed by quenching in different media such as air, water and ice. The quenched specimens were subjected to artificial ageing. Aged specimens were subjected to ultra-sonic test using ultra-sonic flaw detector testing apparatus to identify the common casting defects like porosity, blow holes. Macrostructure and microstructure studies were conducted on as cast and composites in order to investigate the distribution of frit particles retained in matrix material system. Micro structural studies were carried out to understand nature of structure. Density measurement was carried out on both Al6061matrix alloy and Al6061-Frit particulate composite. Hardness tests have been conducted both on Al6061 matrix alloy and Al6061-Frit particulate composite before and after heat treatment. It has been observed under identical heat treatment conditions adopted, Al6061-Frit particulate composites exhibited significant improvement in hardness when compared with Al6061 alloy.

关键词： MMC’s Solutionizing Ageing Density Hardness

Metabolic and hepatic effects of liraglutide,obeticholic acid and elafibranor in diet-induced obese mouse models of biopsy-confirmed nonalcoholic steatohepatitis

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World Journal of Gastroenterology 2018年第2期24卷 179-194页

作者： Kirstine S Tolbol Maria nb Kristiansen Henrik H Hansen Sanne S Veidal Kristoffer TG Rigbolt Matthew p Gillum Jacob Jelsing Niels Vrang Michael Feigh Gubra Aps Horsholm DK-2970Denmark Department of Biomedical Sciences Faculty of Health SciencesUniversity of CopenhagenCopenhagen DK-2200Denmark Section for Metabolic Imaging and Liver Metabolism The Novo Nordisk Foundation Center for Basic Metabolic ResearchFaculty of Health SciencesUniversity of CopenhagenCopenhagen DK-2200Denmark Department of Chemistry Faculty of ScienceUniversity of CopenhagenCopenhagen DK-2200Denmark

AIM To evaluate the pharmacodynamics of compounds in clinical development for nonalcoholic steatohepatitis(NASH) in obese mouse models of *** Male wild-type C57 BL/6 J mice(DIO-NASH) and Lep^(ob/ob)(ob/ob-NASH) mice were fed a diet high in trans-fat(40%), fructose(20%) and cholesterol(2%) for 30 and 21 wk, respectively. prior to treatment, all mice underwent liver biopsy for confirmation and stratification of liver steatosis and fibrosis, using the nonalcoholic fatty liver disease activity score(NAS) and fibrosis staging system. The mice were kept on the diet and received vehicle, liraglutide(0.2 mg/kg, SC, BID), obeticholic acid(OCA, 30 mg/kg pO, QD), or elafibranor(30 mg/kg pO, QD) for eight weeks. Within-subject comparisons were performed on changes in steatosis, inflammation, ballooning degeneration, and fibrosis scores. In addition, compound effects were evaluated by quantitative liver histology, including percent fractional area of liver fat, galectin-3, and collagen 1 *** Liraglutide and elafibranor, but not OCA, reduced body weight in both models. Liraglutide improved steatosis scores in DIO-NASH mice only. Elafibranor and OCA reduced histopathological scores of hepatic steatosis and inflammation in both models, but only elafibranor reduced fibrosis severity. Liraglutide and OCA reduced total liver fat, collagen 1 a1, and galectin-3 content, driven by significant reductions in liver weight. The individual drug effects on NASH histological endpoints were supported by global gene expression(RNA sequencing) and liver lipid *** DIO-NASH and ob/ob-NASH mouse models show distinct treatment effects of liraglutide, OCA, and elafibranor, being in general agreement with corresponding findings in clinical trials for NASH. The present data therefore further supports the clinical translatability and utility of DIO-NASH and ob/ob-NASH mouse models of NASH for probing the therapeutic efficacy of compounds in preclinical d

关键词： Nonalcoholic steatohepatitis Disease models pathology Fibrosis Liver biopsy Transcriptomics pharmacodynamics Glucagon-like peptide-1 receptor peroxisome proliferator-activated receptor Farnesoid X receptor

A review on biomedical and dental applications of cerium oxide nanoparticles——Unearthing the potential of this rare earth metal

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Journal of Rare Earths 2023年第11期41卷 1645-1661,I0001页

作者： Lalitha S Jairam Akshatha chandrashekar T.Niranjana prabhu Sunil Babu Kotha M.S.Girish Indira Mysuru Devraj M.Dhanya Shri K.prashantha Department of pediatric and preventive Dentistry Faculty of Dental SciencesM.S.Ramaiah University of Applied SciencesNew BEL RoadMSR NagarBangalore560054India Department of Chemistry Faculty of Mathematical and Physical SciencesM.S.Ramaiah University of Applied SciencesNo.470-PIV PhasePeenya Industrial AreaBangalore560058India Department of preventive Dentistry Pediatric Dentistry DivisionCollege of DentistryRiyadh Elm UniversityRiyadhKingdom of Saudi Arabia Department of pediatric and preventive Dentistry JSS Dental College&HospitalJSS Academy of Higher Education&ResearchMysuruIndia Center for Research and Innovation Adichunchanagiri School of Natural SciencesAdichunchanagiri UniversityBGSITB.G.Nagara571448India

Nanotechnology deals with particles ranging from 1 to 100 nm in size called as *** nano particles exhibit unique properties which find an application in many industries and medical fields.A growing body of evidence points out the newer developing technologies adopted in the field of medicine in terms of target therapies,imaging systems,drug deliveries,*** through the incorporation of *** oxide nanoparticles have gained attention in the last decade due to exceptional properties such as redox activity,biofilm inhibition,antibacterial activity,anti-inflammatory activity,*** method of synthesis of cerium oxide nanoparticles plays a pivotal role in its *** exhibits redox properties and catalytic activity and thus has found its use in biomedical *** are incorporated into dental materials such as restorative cements/sealants,adhesives,and denture systems to improve their *** the various metal oxide nanoparticles,ce rium oxide nanoparticles(CeO_(2)Nps)are known to exhibit lower toxicity to mammalian cells and possess unique antibacterial *** addition,they exhibit potent properties such as antitumor,antiinflammatory,antibacterial activities,and functions as an ***_(2)Nps have excellent scavenging properties for reactive oxygen species,which is why they are being considered for therapeutic *** this review,various methods of synthesis of CeO_(2)Nps are *** factors that determine the particle size and morphology of these materials are important for biomedical and dental *** is given to preparation methods and variables such as calcination temperature,which have a profound effect on particle size and *** article also presents various applications of CeO_(2)Nps in the biomedical and dental fields.

关键词： Cerium oxide nanoparticles Synthesis Antibacterial activity Biomedical applications Dental applications Rare earths

Body composition changes after transjugular intrahepatic portosystemic shunt in patients with cirrhosis

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World Journal of Gastroenterology 2010年第3期16卷 348-353页

作者： Jonathan Montomoli peter Holland-Fischer Giampaolo Bianchi Henning GrФnbk Hendrik Vilstrup Giulio Marchesini Marco Zoli Department of Internal Medicine Aging and Nephrological DiseasesUniversity of Bologna Department of Medicine V Aarhus University Hospital

AIM:To investigate the effect of transjugular intra-hepatic porto-systemic shunt (TIpS) on malnutrition in portal hypertensive cirrhotic ***: Twenty-one patients with liver cirrhosis and clinical indications for TIpS insertion were investigated before and 1, 4, 12, 52 wk after TIpS. For each patient we assayed body composition parameters [dry lean mass, fat mass, total body water (TBW)], routine liver and kidney function tests, and free fatty acids (FFA). Glucose and insulin were measured for the calculation of the homeostasis model assessment insulin resistance (HOMA-IR); liver function was measured by the galactose elimination capacity (GEC); the severity of liver disease was graded by model for end-stage liver disease (MELD).RESULTS: porto-systemic gradient decreased after TIpS (6.0±2.1 mmHg vs 15.8±4.8 mmHg, ppatients were divided in two groups according to initial body mass index. After TIpS, normal weight patients had an increase in dry lean mass (from 10.9±5.9 kg to 12.7±5.6 kg, p=0.031) and TBW (from 34.5±7.6 L to 40.2±10.8 L,p=0.007), as well as insulin (from 88.9±49.2 pmol/L to 164.7±107.0 pmol/L,p=0.009) and HOMA-IR (from 3.36%±2.18% to 6.18%±4.82%,p=0.023). In overweight patients only FFA increased significantly (from 0.59±0.24 mmol/L to 0.93±0.34 mmol/L, p=0.023).CONCLUSION: TIpS procedure is effective in lowering portal pressure in patients with portal hypertension and improves body composition without significant changes in metabolic parameters.

关键词： Insulin resistance Liver cirrhosis Malnutrition portal hypertension Transjugular intrahepatic porto-systemic shunt

Taguchi Technique for the Simultaneous Optimization of Tribological parameters in Metal Matrix Composite

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Journal of Minerals and Materials Characterization and Engineering 2011年第12期10卷 179-188页

作者： Kumar.T.R. Hemanth R.p. Swamy T.K. chandrashekar Department of Mechanical engineering. UBDT. College of Engineering Davangere India Dept. of Industrial engineering and Management. Sri Siddhartha Institute of Technology Tumkur India Dept. of Mechanical engineering Sri Siddhartha Institute of Technology Tumkur

Taguchi methods have proved to be successful over the last two decades for improvement of product quality and process performance. This study is carried out to simultaneously optimize the tribological properties: wear rate and frictional force of aluminum metal matrix composite. Al-Cu-Mg alloy reinforced with 6 Wt % of titanium dioxide was prepared using stir casting method. Dry sliding wear test was conducted to understand the tribological behavior of samples. The experiments were conducted as per the Taguchi design of experiment. The wear parameters chosen for the experiment were: sliding speed and load and sliding distance. Each parameter was assigned three levels. The experiment consists of 27 tests according to L27 orthogonal array. Signal to noise ratio analysis has been carried out to determine optimal parametric condition, which yields minimum wear rate and frictional force. Harrington’s desirability functional method is adopted for multifunctional optimization of tribological parameters and the confirmation experiments were conducted to verify the predicted model.

关键词： Metal matrix composite Titanium Dioxide Taguchi Technique Signal to noise ratio significant factors.

Impact of device resistances in the performance of graphene‑based terahertz photodetectors

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Frontiers of Optoelectronics 2024年第2期17卷 87-97页

作者： O.Castelló Sofía M.López Baptista K.Watanabe T.Taniguchi E.Diez J.E.Velázquez-pérez Y.M.Meziani J.M.Caridad J.A.Delgado-Notario Department of Applied physics University of Salamanca37008 SalamancaSpain Unidad de Excelencia en Luz y Materia Estructurada(LUMES) University of Salamanca37008 SalamancaSpain Research Center for Electronic and Optical Materials National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan Research Center for Materials Nanoarchitectonics National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan Nanotechnology Group USAL-NanolabUniversity of Salamanca37008 SalamancaSpain

In recent years,graphene field-effect-transistors(GFETs)have demonstrated an outstanding potential for terahertz(THz)photodetection due to their fast response and *** features are essential to enable emerging THz applications,including 6G wireless communications,quantum information,bioimaging and ***,the overall performance of these photodetectors may be utterly compromised by the impact of internal resistances presented in the device,so-called access or parasitic *** this work,we provide a detailed study of the influence of internal device resistances in the photoresponse of high-mobility dual-gate GFET *** dual-gate architectures allow us to fine tune(decrease)the internal resistance of the device by an order of magnitude and consequently demonstrate an improved responsivity and noise-equivalent-power values of the photodetector,*** results can be well understood by a series resistance model,as shown by the excellent agreement found between the experimental data and theoretical *** findings are therefore relevant to understand and improve the overall performance of existing high-mobility graphene photodetectors.

关键词： Graphene THz photodetector Field-effect transistor plasmonic