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Smelling fit： scent marking exposes parasitic infection status in the banded mongoose

Current Zoology 2017年第3期63卷 237-247页

作者： jessica MITCHELL Michael A. CANT emma I.K. VITIKAINEN Hazel j. NICHOLS School of Natural Sciences and Psychology Liverpool John Moores University Liverpool L3 AF UK Centrefor Ecology and Conservation University of Exeter Penryn Campus TRIO 9FE UK

Preference for uninfected mates is presumed beneficial as it minimizes one's risk of contracting an infection and infecting one's offspring. In avian systems, visual ornaments are often used to indicate parasite burdens and facilitate mate choice. However, in mammals, olfactory cues have been proposed to act as a mechanism allowing potential mates to be discriminated by infection status. The effect of infection upon mammalian mate choice is mainly studied in captive rodents where experimental trials support preference for the odors of uninfected mates and some data suggest scent marking is reduced in individuals with high infection burdens. Nevertheless, whether such effects occur in nonmodel and wild systems remains poorly understood. Here, we investigate the interplay between parasite load (estimated using fecal egg counts) and scent marking behavior in a wild population of banded mongooses . Focusing on a costly protozoan parasite of the genus and the nematode worm , we first show that banded mongooses that engage in frequent, intensive scent marking have lower loads, suggesting marking behavior may be an indicator trait regarding infection status. We then use odor presentations to demonstrate that banded mongooses mark less in response to odors of opposite sexed individuals with high and loads. As both of these parasites are known to have detrimental effects upon the health of preweaned young in other species, they would appear key targets to avoid during mate choice. Results provide support for scent as an important ornament and mechanism for advertising parasitic infection within wild mammals.

关键词：寄生虫感染气味标记猫鼬哺乳动物野生种群配偶选择等孢球虫啮齿类动物

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Calibration method to improve the accuracy of THz imaging and spectroscopy in reflection geometry

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Photonics Research 2016年第3期4卷 29-35页

作者： Shuting Fan Edward P.j.Parrott Benjamin S.Y.Ung emma Pickwell-MacPherson Department of Electric and Computer Engineering Hong Kong University of Science and Technology Department of Electronic Engineering The Chinese University of Hong Kong

We introduce a novel method to accurately extract the optical parameters in terahertz reflection imaging. Our method builds on standard self-referencing methods using the reflected signal from the bottom of the imaging window material to further compensate for time-dependent system fluctuations and position-dependent variation in the window thickness. Our proposed method not only improves the accuracy, but also simplifies the imaging procedure and reduces measurement times.

关键词： Calibration method to improve the accuracy of THz imaging and spectroscopy in reflection geometry THz

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Robust and accurate terahertz time-domain spectroscopic ellipsometry

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Photonics Research 2018年第8期6卷 768-775页

作者： XUEQUAN CHEN EDWARD P.j.PARROTT ZHE HUANG HAU-PING CHAN emma PICKWELL-MACPHERSON Department of Electronic Engineering The Chinese University of Hong Kong School of Science Zhejiang University of Science and Technology Department of Electronic Engineering City University of Hong Kong Department of Physics and Astronomy Warwick University

In this work, we show how fiber-based terahertz systems can be robustly configured for accurate terahertz ellipsometry. To this end, we explain how our algorithms can be successfully applied to achieve accurate spectroscopic ellipsometry with a high tolerance on the imperfect polarizer extinction ratio and pulse shift errors. Highly accurate characterization of transparent, absorptive, and conductive samples comprehensively demonstrates the versatility of our algorithms. The improved accuracy we achieve is a fundamental breakthrough for reflectionbased measurements and overcomes the hurdle of phase uncertainty.

关键词：光纤太赫兹椭偏仪通讯技术发展现状

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The grassland carbon cycle:Mechanisms,responses to global changes,and potential contribution to carbon neutrality

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Fundamental Research 2023年第2期3卷 209-218页

作者： Lingli Liu emma j.Sayer Meifeng Deng Ping Li Weixing Liu Xin Wang Sen Yang junsheng Huang jie Luo Yanjun Su joséM.Grünzweig Lin jiang Shuijin Hu Shilong Piao State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China Lancaster Environment Centre Lancaster UniversityLancaster LA14YQUnited Kingdom Department of Evolutionary Biology and Environmental Studies University of ZurichZurich 8057Switzerland Institute of Plant Sciences and Genetics in Agriculture The Robert H.Smith Faculty of AgricultureFood and EnvironmentThe Hebrew University of JerusalemRehovot 7610001Israel School of Biological Sciences Georgia Institute of Technology310 Ferst DriveAtlantaGA 30332United States Department of Plant Pathology North Carolina State UniversityRaleighNC 27607United States Sino-French Institute for Earth System Science College of Urban and Environmental SciencePeking UniversityBeijing 100871China National Hulunber Grassland Ecosystem Observation and Research Station Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081China

Grassland is one of the largest terrestrial biomes,providing critical ecosystem services such as food production,biodiversity conservation,and climate change *** climate change and land-use intensification have been causing grassland degradation and desertification *** one of the primary medium for ecosystem energy flow and biogeochemical cycling,grassland carbon(C)cycling is the most fundamental process for maintaining ecosystem *** this review,we first summarize recent advances in our understanding of the mechanisms underpinning spatial and temporal patterns of the grassland C cycle,discuss the importance of grasslands in regulating inter-and intra-annual variations in global C fluxes,and explore the previously unappreciated complexity in abiotic processes controlling the grassland C balance,including soil inorganic C accumulation,photochemical and thermal degradation,and wind *** also discuss how climate and land-use changes could alter the grassland C balance by modifying the water budget,nutrient cycling and additional plant and soil ***,we examine why and how increasing aridity and improper land use may induce significant losses in grassland C ***,we identify several priorities for future grassland C research,including improving understanding of abiotic processes in the grassland C cycle,strengthening monitoring of grassland C dynamics by integrating ground inventory,flux monitoring,and modern remote sensing techniques,and selecting appropriate plant species combinations with suitable traits and strong resistance to climate fluctuations,which would help design sustainable grassland restoration strategies in a changing climate.

关键词： Climate changes Land-use change Soil Biotic and abiotic interactions Grassland degradation Grassland restoration Carbon accounting Carbon storage and sequestration mechanisms

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High-yield fabrication of perpendicularly magnetised synthetic antiferromagnetic nanodiscs

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Nano Research 2021年第11期14卷 3873-3878页

作者： emma N.Welbourne Tarun Vemulkar Russell P.Cowburn Department of Physics Cavendish LaboratoryUniversity of CambridgeJ.J.Thomson AvenueCambridgeCB30HEUK

Synthetic antiferromagnetic (SAF) particles with perpendicular anisotropy display a number of desirable characteristics for applications in biological and other fluid environments. We present an efficient and effective method for the patterning of ultrathin Ruderman-Kittel-Kasuya-Yoshida coupled, perpendicularly magnetised SAFs using a combination of nanosphere lithography and ion milling. A Ge sacrificial layer is utilised, which provides a clean and simple lift-off process, as well as maintaining the key magnetic properties that are beneficial to target applications. We demonstrate that the method is capable of producing a particularly high yield of well-defined, thin film based nanoparticles.

关键词： nanodiscs synthetic antiferromagnets perpendicular anisotropy sacrificial layers nanofabrication

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High-Intensity Interval Training Prescribed Within the Secondary Severe-Intensity Domain Improves Critical Speed But Not Finite Distance Capacity

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journal of Science in Sport and Exercise 2020年第2期2卷 154-166页

作者： emma jThomas Robert W.Pettitt Mark Kramer Biokinetics and Sport Science Unit Nelson Mandela UniversityPort Elizabeth 6070South Africa Rocky Mountain University of Health Professions ProvoUT 84606USA Physical Activity Sport and Recreation Research Focus AreaNorth West UniversityPotchefstroom 2520South Africa

Purpose Improvements in D'(the fatigability constant for running)subsequent to training interventions remain ***-intensity interval training(HIIT)within the severe intensity domain for short durations(<2-min)have been theorized to improve D'.The purpose of the present study was to assess this in a group of moderately trained *** Eighteen participants completed graded exercise testing(GXT),40-m sprint testing and a 3-min all-out test(3MT)for running to determine key mechanistic and physiological *** were randomly assigned into one of two groups based on intensity prescription(G140%=140%of critical speed[CS]),or time intervals(G90-s=90-s)to complete a twice-weekly training intervention for 6-weeks followed by *** No between-group differences were present either prior to or following the *** and meaning-ful improvements were detected during the post-intervention period for both groups for VO2max(G140%:+7.60%;G90-s:+11.67%),speed evoking VO2max(sVO2max;G140%:+4.33%;G90_s:+2.92%),gas exchange threshold(GET;G140%:+12.02%;G90-s:+20.52%),speed evoking GET(sGET;G140%:+4.17%;G90_s:+7.92%),CS(G140%:M=0.62 m/s;G90-s:M=0.46 m/s),D'(G140%:M=-56.34 m;G90-s:M=-18.36 m),FI%(G140%M=-6.75%;G90-s:M=-4.38%)and maximal distance(G140%:M=49.67 m;G90_s:M=58.38 m).Conclusions The prescribed intensities and durations were insufficient to elicit improvements in D'.Improvements in D'may be dependent on very short-duration intervals(i.e.<60 to 90-s)at speeds exceeding 140%CS but below maximal sprint speed.

关键词： Moderately active Severe intensity Threshold

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Mate-recognition and species boundaries in the ascomycetes

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Fungal Diversity 2013年第1期58卷 1-12页

作者： Simon H.Martin emma T.Steenkamp Michael j.Wingfield Brenda D.Wingfield Department of Genetics Forestry and Agricultural Biotechnology InstituteUniversity of PretoriaPretoria 0002South Africa Department of Microbiology and Plant Pathology Forestry and Agricultural Biotechnology InstituteUniversity of PretoriaPretoria 0002South Africa

Reproductive gene evolution is commonly invoked as a source of reproductive isolation during *** possibility has not been adequately explored in the Ascomycota,the most species-rich fungal *** mechanisms of mate-recognition in this group are relatively simple:a“mating type”locus determines reproductive mode and sexual compatibility,and two pheromone/receptor pairs control sexual ***,ascomycete reproductive genes can experience unique and interesting evolutionary forces,which could lead to rapid *** this review,we examine the mechanisms of sexual interaction in ascomycetes and explore current evidence as to whether these mechanisms allow for species-specificity in *** discuss the evolutionary forces that can drive reproductive gene divergence,how these may apply in the world of ascomycetes,and their possible consequences for speciation.

关键词： Ascomycota Speciation Mating type Pheromone Receptor

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Resveratrol activation of SIRT1/MFN2 can improve mitochondria function,alleviating doxorubicin-induced myocardial injury

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Cancer Innovation 2023年第4期2卷 253-264页

作者： Qingling Zhang Yunpeng Zhang Bingxin Xie Daiqi Liu Yueying Wang Zandong Zhou Yue Zhang emma King Gary Tse Tong Liu Department of Cardiology Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular DiseaseTianjin Institute of CardiologyThe Second Hospital of Tianjin Medical UniversityTianjinChina Epidemiology Research Unit Cardiovascular Analytics GroupChina-UK CollaborationHong KongChina Kent and Medway Medical School CanterburyKentUK

Background Doxorubicin is a widely used cytotoxic chemotherapy agent for treating different ***,its use is associated with dose-dependent cardiotoxicity,causing irreversible myocardial damage and significantly reducing the patient's quality of life and *** this study,an animal model of doxorubicin-induced cardiomyopathy was used to investigate the pathogenesis of doxorubicin-induced myocardial *** study also investigated a possible treatment strategy for alleviating myocardial injury through resveratrol therapy in *** Adult male C57BL/6j mice were randomly divided into a control group and a doxorubicin *** weight,echocardiography,surface electrocardiogram,and myocardial histomorphology were *** mechanisms of doxorubicin cardiotoxicity in H9c2 cell lines were explored by comparing three groups(phosphate-buffered saline,doxorubicin,and doxorubicin with resveratrol).Results Compared to the control group,the doxorubicin group showed a lower body weight and higher systolic arterial pressure,associated with reduced left ventricular ejection fraction and left ventricular fractional shortening,prolonged PR interval,and QT *** abnormalities were associated with vacuolation and increased disorder in the mitochondria of cardiomyocytes,increased protein expression levels of α-smooth muscle actin and caspase 3,and reduced protein expression levels of Mitofusin2(MFN2)and Sirtuin1(SIRT1).Compared to the doxorubicin group,doxorubicin+resveratrol treatment reduced caspase 3 and manganese superoxide dismutase,and increased MFN2 and SIRT1 expression *** Doxorubicin toxicity leads to abnormal mitochondrial morphology and dysfunction in cardiomyocytes and induces apoptosis by interfering with mitochondrial *** ameliorates doxorubicin-induced cardiotoxicity by activating SIRT1/MFN2 to improve mitochondria function.

关键词： cardio-oncology doxorubicin-induced cardiomyopathy mitochondriafunction resveratrol SIRT1 agonists

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Three-dimensional perfused human in vitro model of nonalcoholic fatty liver disease

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World journal of Gastroenterology 2017年第2期23卷 204-215页

作者： Tomasz Kostrzewski Terri Cornforth Sophie A Snow Larissa Ouro-Gnao Cliff Rowe emma M Large David j Hughes CN Bio Innovations Limited Welwyn Garden City AL7 3AXUnited Kingdom

AIM To develop a human in vitro model of non-alcoholic fatty liver disease(NAFLD), utilising primary hepatocytes cultured in a three-dimensional(3D) perfused platform. METHODS Fat and lean culture media were developed to directly investigate the effects of fat loading on primary hepatocytes cultured in a 3D perfused culture system. Oil Red O staining was used to measure fat loading in the hepatocytes and the consumption of free fatty acids(FFA) from culture medium was monitored. Hepatic functions, gene expression profiles and adipokine release were compared for cells cultured in fat and lean conditions. To determine if fat loading in the system could be modulated hepatocytes were treated with known anti-steatotic compounds. RESULTS Hepatocytes cultured in fat medium were found to accumulate three times more fat than lean cells and fat uptake was continuous over a 14-d culture. Fat loading of hepatocytes did not cause any hepatotoxicity and significantly increased albumin production. Numerous adipokines were expressed by fatty cells and genes associated with NAFLD and liver disease were upregulated including: Insulin-like growth factorbinding protein 1, fatty acid-binding protein 3 and CYP7A1. The metabolic activity of hepatocytes cultured in fatty conditions was found to be impaired and the activities of CYP3A4 and CYP2C9 were significantlyreduced, similar to observations made in NAFLD patients. The utility of the model for drug screening was demonstrated by measuring the effects of known antisteatotic compounds. Hepatocytes, cultured under fatty conditions and treated with metformin, had a reduced cellular fat content compared to untreated controls and consumed less FFA from cell culture *** The 3D in vitro NAFLD model recapitulates many features of clinical NAFLD and is an ideal tool for analysing the efficacy of anti-steatotic compounds.

关键词：非酒精的脂肪肝疾病肝疾病三维的房间文化 Organ-on-chip 主要房间文化脂肪肝 Hepatocytes

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The role of aluminium in the preservation of microbial biosignatures

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Geoscience Frontiers 2019年第3期10卷 1125-1138页

作者： Alan Levett emma j.Gagen Hui Diao Paul Guagliardo Llew Rintoul Anat Paz Paulo M.Vasconcelos Gordon Southam School of Earth and Environmental Sciences University of Queensland Centre for Microscopy and Microanalysis University of Queensland Centre for Microscopy Characterisation and Analysis University of Western Australia School of Chemistry Physics & Mechanical EngineeringQueensland University of Technology

Demonstrating the biogenicity of presumptive microfossils in the geological record often requires supporting chemical signatures, including isotopic signatures. Understanding the mechanisms that promote the preservation of microbial biosignatures associated with microfossils is fundamental to unravelling the palaeomicrobiological history of the material. Organomineralization of microorganisms is likely to represent the first stages of microbial fossilisation and has been hypothesised to prevent the autolytic degradation of microbial cell envelope structures. In the present study, two distinct fossilisation textures(permineralised microfossils and iron oxide encrusted cell envelopes)identified throughout iron-rich rock samples were analysed using nanoscale secondary ion mass spectrometry(NanoSIMS). In this system, aluminium is enriched around the permineralised microfossils, while iron is enriched within the intracellularly, within distinct cell envelopes. Remarkably,while cell wall structures are indicated, carbon and nitrogen biosignatures are not preserved with permineralised microfossils. Therefore, the enrichment of aluminium, delineating these microfossils appears to have been critical to their structural preservation in this iron-rich environment. In contrast,NanoSIMS analysis of mineral encrusted cell envelopes reveals that preserved carbon and nitrogen biosignatures are associated with the cell envelope structures of these microfossils. Interestingly, iron is depleted in regions where carbon and nitrogen are preserved. In contrast aluminium appears to be slightly enriched in regions associated with remnant cell envelope structures. The correlation of aluminium with carbon and nitrogen biosignatures suggests the complexation of aluminium with preserved cell envelope structures before or immediately after cell death may have inactivated autolytic activity preventing the rapid breakdown of these organic, macromolecular ***, these results highlig

关键词： Aluminium Microfossils Biosignatures NanoSIMS Organomineralisation

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