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Personality and behavioral changes in Asian elephants(elephas maximus)following the death of herd members

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Integrative Zoology 2021年第2期16卷 170-188页

作者： Lucy RUTHeRFORD Lindsay e.MURRAY School of Psychology University of ChesterChesterUK

elephants are highly social beings with complex individual *** know that elephants have a general interest in death,investigating carcasses,not just limited to kin;however,research does not explore in depth whether individuals change their behavior or personality following traumatic events,such as the death of a *** a captive herd of Asian elephants(elephas maximus)housed at Chester Zoo,uk,we measured social behavior and proximity and personality using the Ten-Item Personality Inventory,and found age-related and relationship-related changes in both behavior and personality following the deaths of herd ***,the herd spent less time socializing and engaging in affiliative behaviors following the death of the adult female when compared to baseline data,yet spent more time engaging in these behaviors after the death of two *** death of the central female had a dramatic impact on her infant calf,resulting in increasingly withdrawn behavior,yet had the opposite effect on her adult daughter,who subsequently established a more integrated role within the *** Stability fell in the motherless calf but rose in an adult female,who had lost her adult daughter,but had a new calf to care *** suggest that the greater impact on the behavior and personality of surviving herd members following the deaths of calves,compared to an adult member,attests to the significance of the unifying role played by calves within an elephant herd.

关键词： captive environment death elephant grief proximity

Statistical research on the motion properties of the magnetotail current sheet:Cluster observations

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Science China(Technological Sciences) 2010年第6期53卷 1732-1738页

作者： H.ReMe e.LUCeK Centre D'etude Spatiale des Rayonnements University Paul SabatierUniversity of ToulouseToulouseFrance UMR 5187 CNRSToulouseFrance Space and Atmospheric Physics Group Blackett LaboratoryImperialCollegeLondonUK

The origin of the flapping motion of the earth’s magnetotail current sheet is one of the most important problems in the magnetotail *** Cluster data,we make a statistical research on the motion properties of the magnetotail current sheet of 2001 and *** calculate the velocities of the magnetotail current sheet using new methods and obtain the distribution of the magnetotail current sheet velocities in the X-Y plane in GSe coordinate *** results show that although most of the current sheets were propagating toward the tail flanks and those of the exceptions lay in dusk side,which is consistent with previous studies,the proportions of the current sheet which were propagating toward midnight (where |YGSe|=0) were higher than those in previous *** of the current sheet in the middle area (|YGSe|e) of the magnetotail are *** high value of the Z component of the velocity further confirms that the middle area of the magnetotail might be a source region for the motion of the current sheets which were propagating towards the tail *** to our case studies,the way the current sheets propagated toward midnight area differs significantly from that toward dusk and dawn side,from which we infer that there might be two different kinds of current sheet motions originated from different *** statistical results of this paper may give some clues for further studies on the origin of the flapping motion of the magnetotail current sheet.

关键词： magnetotail current sheet flapping motion source

Biocompatibility evaluation in vitro. Part III: Cytotoxicity expression of human and animal osteoblasts on the biomaterials

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Journal of Central South University 2001年第3期13卷 147-155页

作者： RUAN Jian-ming 1,M.H. Grant 2 (1. State Key Laboratory for Powder Metallurgy, Central South University, Changs ha 410083, China 2. Bioengineering Unit, Strathclyde University, Glasgow, G4 0NW, uk) State Key Laboratory for Powder Metallurgy Central South University Changsha China Bioengineering Unit Strathclyde University Glasgow UK

exclusion and inflammation in the clinic are observe d for various reas ons including material che- mical composition, physical properties as well a s macr o- and micro-structure of the implants, surface condition of the implants, and also patient dependent factors. Cytotoxicity expression of cells is a central issue i n current biocompatibility to screen the potential implant materials and drugs. This study was aimed at investigation reaction between the potential implant mat erials and surround tissue. Cytotoxicity of human and rat osteoblast in the mate rial extracts was determinated by testing standards such as GHS assay, MTT assay , alkaline phosphatase activity assay, LDH assay, and Lowry assay. Research resu lts demonstrated that compared with the control condition polystyrene culture pl a te both human and rat osteoblast cells have normal phenotypic expression in hydr oxyapatite extract, and this expression was statistically restricted in hydroxya patite-spinel extract. How- ever, this restrict, e.g. cytotoxicity could be partially eliminated by immersion treatment of the materials in culture medium.

关键词： biomaterial cytotoxicity biological molecular technique

Chemical forms and extractability of iron in sediments of three contrasting lakes of China and uk

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Journal of environmental Sciences 2003年第6期15卷 728-733页

作者： Gibson C.e.,Stewart B.M. Key Laboratory of Terrestrial ecological Process Institute of Applied ecology Chinese Academy of Sciences Department of Agricultural and environmental Science Queen's University Belfast Shenyang 110016 China Newforge Lane Belfast BT9 5PX uk

Iron is a limiting factor for the eutrophication of lakes, especially those lakes that are enriched with phosphorus. extractability of iron in sediments of West Lake and Taihu Lake in China and Lower Lough erne in Northern Ireland of uk was comparatively investigated on the basis of analysing chemical forms of iron using different extractants. It was shown that extractable iron in sediments of the lakes was greatly different using various extractants. Reactive iron or easily released iron such as “active" iron oxides, total free iron oxide and water-soluble iron was not high, only accounting for 0.01%—0.15% of total iron. The efficiency of the extractants for exchangeable iron was decreased in the sequence 0.1 mol/L HCl DTPA+TeA mixed solution > 1 mol/L NH 4OAc > 0.5 mol/L MgCl 2 = 0.5 mol/L CaCl 2. It seems that the complexion of iron by organic matter was not strong because the concentration of organically bound iron was significantly lower than the concentration it was forecasted. extractable iron is not entirely consistent with or dependent on total iron in lake sediments. To a certain extent, phosphate can inhibit the release of iron in sediments of the lakes. The selection of extractants is thus the first key step to evaluate bioavailability of iron in lake sediments.

关键词： iron chemical form extractability lake sediment eutrophication

Critiquing and Joining Intersections of Disaster,Conflict,and Peace Research

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International Journal of Disaster Risk Science 2020年第5期11卷 555-567页

作者： Laura e.R.Peters Ilan Kelman College of earth.Ocean and Atmospheric SciencesOregon State UniversityCorvallis.OR 97331USA Institute for Risk and Disaster Reduction and Institute for Global HealthUniversity College LondonLondon WC1E 6BT.UK University of Agder.4630 Kristiansand Norway

Disaster research,conflict research,and peace research have rich and deep histories,yet they do not always fully intersect or learn from each other,even when they investigate if and how disasters lead to conflict or *** has tended to focus on investigating causal linkages between disaster(including those associated with climate change)and conflict,and disaster diplomacy emerged as a thread of explanatory research that investigates how and why disaster-related activities do and do not in fluence peace and ***,definitive conclusions on the disaster-conflict-peace nexus have evaded scientific consensus,in part due to conceptual,methodological,and interpretive differences among *** article highlights that this nexus would benefit from a more robust engagement with each field's foundational research that explores beyond binary and crude *** are concepts of destructive and constructive conflict;direct,structural,and cultural violence,and their relationships to vulnerability;negative and positive peace;and the ideals and realities of peacebuilding and conflict *** article demonstrates how integrated scholarship could open up and advance new lines of questioning,with implications for developing cohere nt research,policy,and *** article concludes by offering recommendations for how to better connect disaster,conflict,and peace research.

关键词： Climate change Conflict research Disaster diplomacy Disaster risk reduction Peace research

Instantaneous frequency and wave mode identification in a magnetosheath using few spatial points

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Chinese Physics B 2013年第8期22卷 496-501页

作者： Nathaniel e U Beloff N George N J Department of Physics Akwa Ibom State UniversityNigeria University of Sussex Brighton UK

Observational data such as those obtained from the magnetosheath in the downstream of earth＇s bow shock have waveforms that differ from those of sinusoidal signals. In practice, they are not even aggregates of sinusoidal signals. Therefore, the frequency decomposition for the data requires technique that will account for the time-varying features of the data that will lead to deduction of physical meaning of the observations. The combination of empirical mode decompo- sition （eMD） and Hilbert transform has been used for extracting the various contributing oscillatory modes （eMDs） and the instantaneous frequency determination （Hilbert transform） of every physically meaningful mode called intrinsic mode func- tion （IMF）. The resulting instantaneous frequencies are used to determine instantaneous wave vectors. The combination of the instantaneous frequencies and wave vectors is useful in the identification of wave modes based on the characteristics of the waves. The results show that eMD-Hilbert can be more reliable than simple Hilbert transform alone.

关键词： eMD-Hilbert transform instantaneous frequency and wave vector

Screw dislocations interacting with two asymmetrical interfacial cracks emanating from an elliptical hole

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Chinese Physics B 2013年第1期22卷 356-362页

作者：曾鑫方棋洪刘又文 P. H. Wen State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan University College of Mechanical and Vehicle engineering Hunan University School of engineering and Material Sciences Queen Mary University of London

The interaction between screw dislocations and two asymmetrical interfacial cracks emanating from an elliptic hole under loads at infinity is studied. The closed-form solution is derived for complex potentials. The stress intensity factor and the critical applied stress for the dislocation emission are also calculated. In the limiting cases, well-known results can be obtained from the present solutions. Moreover, new exact solutions for a screw dislocation interacting with some complicated cracks are derived. The results show that the shielding effect increases with the increase in the length of the other cracks and the minor semi axis, but decreases with the increase of dislocation azimuth. The repulsion acting on the dislocation from the other phase and the other crack extend in the horizontal direction, which makes the dislocation emission at the crack tip take place more easily, but the minor semi axis of the elliptical hole extending in the vertical direction makes it more difficult.

关键词： interfacial crack elliptic hole shielding effect dislocation emission

Static and Dynamic Mechanical Properties of Acrylic Denture-Base Resins Cross-Linked with Polyvinylchloride

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材料科学与工程（中英文版） 2011年第4期5卷 421-430页

作者： emmanuel rotimi Sadiku Olusesan Frank Biotidara Department of Polymer Technology Tshwane University of Technology Lynnwoodridge 0040 South Africa

Static mechanical data (creep, at room temperature and at different loading levels) using a three-point bending test method and the viscoelastic characteristics (using the Dynamic Mechanical Thermal Analyser, DMTA) at a temperature range of between 40 °C and 155 °C and a frequency of 1 Hz), of acrylic denture-base resins that incorporate polyvinyl chloride (PVC) power were studied. Characteristic creep curves obeying an exponential growth as a function of time represented by: J(t) = A + Blog(t), where J(t) is the time-dependent deformation in time, t with A and B as constants, which depend on the materials properties, applied load and temperature, were obtained. There is a gradual decrease in storage modulus, e" with increasing temperature until a critical temperature is reached which depends on the resin type. For the commercial Perspex, a rapid decrease in modulus occurred above 110 °C, which is just above the normally accepted Tg for polymethyl methacrylate, PMMA. For the heat-cured dental resin, QC-20, the critical temperature is higher, at about 120 °C. For the cold-cured dental resin, Pour-n-cure, it softens at about 70 °C and the Maxum, the softening occurs at about 80 °C. The low softening temperatures for the cold-cured are attributed to the presence of residual monomer. However, it is important to recognize the fact that the moduli of the dental resins are somewhat higher than that of the commercial Perspex at ≈40 °C, which is just above the mouth temperature, 37 °C. This is attributed to the possibility of cross-linking, as demonstrated by the limited swelling in acetone. Static Young’s Modulus decreases, marginally for all samples tested, with increasing nominal loading times (1, 15.85 and 1,000 seconds).

关键词：聚甲基丙烯酸甲酯树脂类型聚氯乙烯动态力学静态性能交联义齿

Vegetation composition of old extensive green roofs(from 1980s Germany)

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ecological Processes 2014年第1期3卷 225-235页

作者： Christine e Thuring Nigel Dunnett Department of Landscape Floor 9The Arts TowerWestern BankSheffieldSouth Yorkshire S102TNUK

Introduction:Since their development in the late 1970s in Germany,extensive green roofs(eGR)have become increasingly popular as mitigation tools for urban environmental issues around the *** are planted with select species,which ensure consistent cover and performance over *** research presented herein is part of a systematic re-evaluation of eGR technology since the German industry ***:Given the opportunity to access a small sample of old eGRs installed over 20 years ago in south-west Germany,this research surveyed the vegetation and substrate with an interest in describing these parameters with time-through-space ***:Similar to previous studies,this preliminary work found correlations between roof age with vegetation(cover abundance and species diversity)and substrate properties(e.g.,depth,organic content,pH,and nutrients).Roof age had positive relationship with soil organic content(Corg),and negative relationships with substrate depth and soil *** soil variables are inter-related,as shallow acidic substrates create unfavourable conditions for decomposition and thereby the accumulation of *** variables correlated with eGR vegetation,suggesting a trend of simplified species composition over ***,Corg had a negative relationship with cover and species diversity of most life forms;only Sedum species had positive associations with ***:Considering the dynamics associated with shallow mineral substrates,and the greater floristic diversity of younger roofs,simple Sedum-based vegetation may represent a steady state for conventional eGRs.

关键词： Biodiversity extensive green roofs Germany Long-term performance Plant life forms Sedum Species diversity Substrate depth