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Chinese Physics Letters 2014年第12期31卷 111-114页

作者：叶峰鲍威池松雪 Antonio M. dos Santos jamie j. molaison 方明虎王杭栋毛乾辉汪晋辰刘娟娟盛洁明 Quantum Condensed Matter Division Oak Ridge National Laboratory Oak Ridge 37831 USA Department of Physics and Astronomy University of Kentucky Lexington 40506 USA Department of Physics Renmin University of China Beijing 100872 Department of Physics Zhejiang University Hangzhou 310027

The recently discovered metal-intercalated iron selenide superconductors A2Fe4Se5 （A=K, Cs, T1- K, Rb, T1-Rb）（245） compounds, with Tc ～30K, have attracted much interest A high transition- temperature （TN ≈ 470-560K） and large magnetic moment （3.3μB/Fe） block antiferromagnetic （AFM） order exists in the superconducting samples. Mag- netic order-parameter experiences an anomaly when Tc is approached. The superconductors crystal- lize with a highly ordered √5 × √5 superstructure, in which the Fel site of the I4/m structure is only a few percents occupied and the Fe2 site is fully occupied. The non-superconducting samples at low-T also crystallize in the I4/m structure, while both Fe sites are fractionally occupied, since the numbers of the Fe vacancies in the samples and the vacant sites in the √5 × √5 pattern are mismatched. The partially ordered √5× √5 vacancy order becomes one of three competing phases for temperature below room temperature up to ～ 500K, namely, these sam- ples are phase-separated and in the miscibility gap 1lacier the n,mhi^nt condition.

关键词： NEUTRON scattering HIGH pressure (Technology) SINGLE crystals IRON compounds MAGNETIC materials VACANCIES in crystals SUPERCONDUCTORS

Tuning the translational freedom of DNA for high speed AFM

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Nano Research 2015年第6期8卷 1811-1821页

作者： Andrew j. Lee Michal Szymonik jamie K. Hobbs Christoph Walti Bioelectronics School of Electronic and Electrical Engineering University of Leeds Leeds LS2 9JT UK Department of Physics and Astronomy University of Sheffield Sheffield 53 7RH UK

Direct observation is arguably the preferred way to investigate the interactions between two molecular complexes. With the development of high speed atomic force microscopy （AFM）, it is becoming possible to observe directly DNA-protein interactions with relevant spatial and temporal resolutions. These interactions are of central importance to biology, bionanotechnology, and functional biologically inspired materials. As in all microscopy studies, sample preparation plays a central role in AFM observation and minimal perturbation of the sample is desired. Here, we demonstrate the ability to tune the interactions between DNA molecules and the surface to create an association strong enough to enable high-resolution AFM imaging while also providing sufficient translational freedom to allow the relevant protein-DNA interactions to take place. Furthermore, we describe a quantitative method for measuring DNA mobility, while also determining the individual forces contributing to DNA movement. We found that for a weak surface association, a significant contribution to the movement arises from the interaction of the AFM tip with the DNA. In combination, these methods enable the tuning of the surface translational freedom of DNA molecules to allow the direct study of a wide range of nucleo-protein interactions by high speed atomic force microscopy.

关键词： high speed atomic forcemicroscopy (HS-AFM) DNA protein bionanotechnology

Assessment strategies and fighting patterns in animal contests： a role for serotonin？

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Current Zoology 2016年第3期62卷 257-263页

作者： Andrew N. BUBAK Alison R. GERKEN Michael j. WATT jamie D, COSTABILE Kenneth j. RENNER j.hn G. SWALLOW Integrative Biology University of Colorado-Denver Denver CO 80217-3364 USA Molecular Genetics and Microbiology University of Florida Gainesville FL 32611 USA Center for Brain and Behavior Research Basic Biomedical Sciences University of South Dakota Vermillion SD 57069 USA Biology Department University of South Dakota Vermillion SD 57069 USA

Accurate assessment of the probability of success in an aggressive confrontation with a conspecific is critical to the survival and fitness of the individuals. Various game theory models have examined these assessment strategies under the assumption that contests should favor the animal with the greater resource-holding potential （RHP）, body size typically being the proxy. Mutual assessment asserts that an individual can assess their own RHP relative to their opponent, allowing the inferior animal the chance to flee before incurring unnecessary costs. The model of self-determined persistence, however, assumes that an individual will fight to a set personal threshold, independ- ent of their opponent＇s RHP. Both models have been repeatedly tested using size as a proxy for RHP, with neither receiving unambiguous support. Here we present both morphological and neuro- physiological data from size-matched and mismatched stalk-eyed fly fights. We discovered differ- ing fighting strategies between winners and losers. Winners readily escalated encounters to higher intensity and physical contact and engaged in less low-intensity, posturing behaviors compared with losers. Although these fighting strategies were largely independent of size, they were associ- ated with elevated levels of 5-HT. Understanding the neurophysiological factors responsible for mediating the motivational state of opponents could help resolve the inconsistencies seen in cur- rent game theory models. Therefore, we contend that current studies using only size as a proxy for RHP may be inadequate in determining the intricacies of fighting ability and that future studies investigating assessment strategies and contest outcome should include neurophysiological data.

关键词： aggression assessment fighting strategies serotonin monoamines resource-holding potential.

Physical separation from the mate diminishes male＇s attentiveness towards other females： a study in monogamous prairie voles Microtus ochrogaster

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Current Zoology 2017年第5期63卷 537-544页

作者： Christine j. DELEVAN Natalia A. RODRIGUEZ Karine M. LEGZIM Fayeza ALIOU jamie T. PARKER Maryam BAMSHAD Department of Biological Sciences Lehman College--The City University of New York Bronx NY 10468 USA

We tested whether continuous cohabitation in monogamous voles affects the mated male＇s atten-tiveness to his breeding partner versus another female. Each male was housed in a 3-chamber ap-paratus with a Focal female （FF） and a Control female （CF） for 13 days then placed in a T-maze toassess his attentiveness to and memory of those females. The Distal male remained physically sep-arated from both females, but received their distal cues. The Separate male cohabited with the FFfor 3 days then remained physically separated from both females. The Disrupt male＇s continuouscohabitation with the FF was disrupted by having him physically separated from her after 10 daysand placed with the CF for the last 3 days. The Continuous male cohabited continuously with the FFfor 13 days. With females in the T-maze, the Separate and Disrupt males spent more time near theFF＇s box and the Disrupt males spent more time manipulating the FF＇s box than the CF＇s box. TheSeparate males groomed themselves more when near the FF＇s box than the CF＇s box. The Distaland Continuous males＇ attentiveness to the two females did not differ. Results suggest that phys-ical distance from the partner may reduce male＇s attentiveness toward other potential *** voles might be similar to socially monogamous primates in using tactile cues as a signal formaintaining their social bonds.

关键词： attachment, monogamy, partner preference, partner separation, social cognition.

Measurement and quantification of caking in excipients and food products with emphasis on the non-homogeneous interaction with ambient moisture

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Particuology 2021年第3期19卷 75-83页

作者： Katrina Brockbank Brian Armstrong jamie Clayton Freeman Technology Ltd 1 Miller CourtSevern DriveTewkesburyGloucestershireGL208DNUK

Whilst caking occurs via several different mechanisms,absorption and migration of moisture is frequently the most dominant mechanism within the food and pharmaceutical *** understanding the propensity to cake is important for minimising down-stream process issues,however most characterisation techniques assume that moisture induced caking occurs homogenously through the sample resulting in a uniformly caked powder *** this study,the effect of moisture induced caking on powder flowability was investigated using powder *** materials,including skimmed milk powder(SMP)and sulphated methyl ester(SME)were stored for several days under controlled humidity *** flow energies,a measure of the resistance to flow,were measured at 24 h intervals using an FT4 Powder *** the energy is measured as a function of the bed height,variations in the powder bed are also *** results demonstrated that caking does not always occur uniformly,instead a caked region(or crust)forms at the air-powder interface and then progresses through the powder ***,the strength of this caked region was shown to increase over several days before stabilising.

关键词： Powder Caking Crust formation Powder rheometry Relative humidity

A machine learning method to quantitatively predict alpha phase morphology in additively manufactured Ti-6Al-4V

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npj.Computational Materials 2023年第1期9卷 338-352页

作者： Zhuohan Cao Qian Liu Qianchu Liu Xiaobo Yu jamie j.Kruzic Xiaopeng Li School of Mechanical and Manufacturing Engineering University of New South Wales(UNSW Sydney)SydneyNSW 2052Australia Platforms Division Defence Science and Technology GroupMelbourneVIC 3207Australia

Quantitatively defining the relationship between laser powder bed fusion(LPBF)process parameters and the resultant microstructures for LPBF fabricated alloys is one of main research *** date,achieving the desired microstructures and mechanical properties for LPBF alloys is generally done by time-consuming and costly trial-and-error experiments that are guided by human ***,we develop an approach whereby an image-driven conditional generative adversarial network(cGAN)machine learning model is used to reconstruct and quantitatively predict the key microstructural features(e.g.,the morphology of martensite and the size of primary and secondary martensite)for LPBF fabricated *** results demonstrate that the developed image-driven machine learning model can effectively and efficiently reconstruct micrographs of the microstructures within the training dataset and predict the microstructural features beyond the training dataset fabricated by different LPBF parameters(i.e.,laser power and laser scan speed).This study opens an opportunity to establish and quantify the relationship between processing parameters and microstructure in LPBF Ti-6Al-4V using a GAN machine learning-based model,which can be readily extended to other metal alloy systems,thus offering great potential in applications related to process optimisation,material design,and microstructure control in the additive manufacturing field.

关键词： martensite microstructure alloy

The relationship of high-intensity cross-training with arterial stiffness

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j.urnal of Sport and Health Science 2019年第4期8卷 370-375页

作者： jamie F.Burr j.nny L.Beck j.hn j.Durocher Department of Human Health and Nutritional Sciences University of GuelphGuelphON NIG 2W1Canada Applied Human Sciences University of Prince Edward IslandCharlottetownPE CIA 4P3Canada Department of Biological Sciences Michigan Technological UniversityHoughtonMI 49931USA

Background'.Central arterial stiffness is a cardiovascular risk factor that can be readily affected through engagement in physical exercise training,with resistance and aerobic exercise having disparate *** the growing popularity of high-intensity cross-training(HICT),little is currently known about the effects of this mixed modality exercise stimulus on arterial ***,the purpose of this study was to characterize the arterial stiffness of habitual HICT participants *** active and sedentary controls using a cross-sectional ***'.A total of 30 participants were recruited:10 middle-aged long-term participants of HICT(CrossFit)and 20 age,sex,and height matched controls(10 recreationally active,10 sedentary).Central and peripheral pulse wave velocities were measured for the carotid-femoral and femoral-dorsalis pedis arterial *** fitness(maximal oxygen uptake,VChmax)was measured and typical exercise participation rates were self-reported for each ***'.HICT participants manifested central pulse wave velocity(PWV)(5.3±1.0 m/s,mean±SD)and VChmax(43±6 mL/kg/min)values nearly identical to active *** active groups had significantly better values than sedentary controls(7.1±1.0 m/s,p≤0.001;and 32±7 mL/kg/min,p=0.01).No differences were observed in peripheral PWV between ***'.Habitual participation in HICT exercise was not associated with increased central nor peripheral arterial ***-term HICT participants presented with similar fitness and arterial stiffness as compared with participants who practiced traditional aerobic *** to sedentary living,HICT may offer musculoskeletal and cardiovascular health benefits without negatively impacting arterial stiffness.

关键词： Circuit training CrossFit Pulse wave velocity Resistance exercise Vascular Weight training

Pyramiding disease resistance genes in elite winter wheat germplasm for Western Canada

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The Crop j.urnal 2019年第6期7卷 739-749页

作者： AndréLaroche Michele Frick Robert j.Graf jamie Larsen j.hn D.Laurie Agriculture and Agri-Food Canada Lethbridge Research and Development CentreLethbridgeAlberta T1J 4B1Canada Agriculture and Agri-Food Canada Harrow Research and Development Centre2585 County Road 20HarrowOntario N0R 1G0Canada

We report on pyramiding different disease resistance genes against fungal pathogens in Canadian winter wheat germplasm based on available DNA markers and gene *** resistance represents a safe, economical and ecological method for protecting plants, growers and the health of consumers. Maj.r diseases of wheat on the Canadian Prairies are common bunt, rusts(leaf, stem and stripe) and Fusarium head blight. Over the years markers for resistance genes against these diseases have been identified and used by the international wheat community. We describe markers that we have used to pyramid different resistance genes and indicate their presence in Canadian winter wheat cultivars issued from the winter wheat breeding program at the Agriculture and Agri-Food Canada,Lethbridge Research and Development Centre, the only winter wheat breeding program in Western Canada actively delivering new varieties for all regions of the Canadian *** sources of resistance and identities of PCR primers and amplification conditions are indicated to enable the transfer and pyramiding of different resistance(R) genes to breeding lines. We conclude by reviewing new tools for identifying R genes in wheat and indicate how mutagenesis and gene editing can help future efforts to extend the protection offered by known R genes.

关键词： Bunt Gene pyramiding Wheat rusts Marker-assisted selection Triticum aestivum

Poly(ethylene glycol)hydrogel elasticity influences human mesenchymal stem cell behavior

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Regenerative Biomaterials 2018年第3期5卷 167-175页

作者： Anna K.Whitehead Haley H.Barnett Mary E.Caldorera-Moore jamie j.Newman School of Biological Sciences Department of Biomedical Engineering Louisiana Tech UniversityRustonLA 71272USA

Coordinated investigations into the interactions between biologically mimicking(biomimetic)material constructs and stem cells advance the potential for the regeneration and possible direct replacement of diseased cells and *** clinically relevant therapies will require the development and optimization of methods that mass produce fully functional cells and *** advances in the design and synthesis of biomaterial scaffolds,one of the biggest obstacles facing tissue engineering is understanding how specific extracellular cues produced by biomaterial scaffolds influence the proliferation and differentiation of various cell *** elasticity is one such tailorable property of synthetic scaffolds that is known to differ between ***,we investigate the interactions between an elastically tailorable polyethylene glycol(PEG)-based hydrogel platform and human bone marrow-derived mesenchymal stem cells(hMSCs).For these studies,two different hydrogel compositions with elastic moduli in the ranges of 50-60 kPa and 8-10 kPa were *** findings demonstrate that the different elasticities in this platform can produce changes in hMSC morphology and proliferation,indicating that the platform can be implemented to produce changes in hMSC behavior and cell state for a broad range of tissue engineering and regenerative ***,we show that the platform’s different elasticities influence stem cell differentiation potential,particularly when promoting stem cell differentiation toward cell types from tissues with stiffer *** findings add to the evolving and expanding library of information on stem cell-biomaterial interactions and opens the door for continued exploration into PEG-based hydrogel scaffolds for tissue engineering and regenerative medicine applications.

关键词： biomaterial-cell interaction scaffolds stem cells

Maturity-associated considerations for training load,inj.ry risk,and physical performance in youth soccer:One size does not fit all

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j.urnal of Sport and Health Science 2021年第4期10卷 403-412页

作者： Chris Towlson jamie Salter j.ck D.Ade Kevin Enright Liam D.Harper Richard M.Page j.mes j.Malone Department of Sport Health and Exercise ScienceUniversity of HullHull HU67RXUK School of Sport York St John UniversityYork YO317EXUK Liverpool FC Academy Liverpool Football ClubLiverpool L337EDUK Research Institute for Sport and Exercise Sciences L3Liverpool John Moores UniversityLiverpool L33AUK Human and Health Sciences University of HuddersfieldHuddersfield HD13DHUK Department of Sport and Physical Activity Edge Hill UniversityOrmskirk L394QPUK School of Health Sciences Liverpool Hope UniversityLiverpool L169JDUK

Biological maturation can be defined as the timing and tempo of progress to achieving a mature *** estimation of age of peak height velocity(PHV)or percentage of final estimated adult stature attainment(%EASA)is typically used to inform the training process in young *** youth soccer,maturity-related changes in anthropometric and physical fitness characteristics are diverse among individuals,particularly around *** this time,players are also at an increased risk of sustaining an overuse or growth-related *** a result,the implementation of training interventions can be *** purpose of this review was to(1)highlight and discuss many of the methods that can be used to estimate maturation in the applied setting and(2)discuss the implications of manipulating training load around PHV on physical development and inj.ry *** have provided key stakeholders with a practical online tool for estimating player maturation status(Supplementary Maturity Estimation Tools).Whilst estimating maturity using predictive equations is useful in guiding the training process,practitioners should be aware of its *** increase the accuracy and usefulness of data,it is also vital that sports scientists implement reliable testing protocols at predetermined time-points.

关键词： Growth Inj.ry Maturation Soccer Training