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Effect of losing a fight on later agonistic behavior toward unfamiliar conspecifics in male Syrian hamsters

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Current Zoology 2011年第4期57卷 449-452页

作者： Javier DElBARCO-TRIllO robert E. johnston Comell University Department of Psychology Uris Hall Ithaca NY 14853 USA

In many species, agonistic interactions result in social relationships that are stable over time. In Syrian hamsters, two unfamiliar males that are placed together will fight vigorously and a clear winner/loser relationship is usually established. In subsequent interactions, the loser will flee soon after detecting the familiar winner. Here we tested the hypothesis that losing a fight with a conspecific will affect future agonistic interactions not only toward that individual （i.e., the familiar winner） but also toward unfamiliar conspecifics. To test this hypothesis we paired two Syrian hamster males in three trials on one day in which the loser had tile opportunity to escape the winner. The next day the loser was paired with an unfarniliar male, also for three trials. If he lost again, he was tested on a third day with a third unfamiliar male. Subjects were those males that were losers on all three days. The latency to escape on the first trial on Days 2 and 3 was significantly shorter than on the first trial on Day l, indicating that losing against the first male affected the response toward unfamiliar males. However, the latency to escape on the first trial on Days 2 and 3 was significantly longer than that on the third trial on the preceding day, indicating that a loser treats unfamiliar males differently than a familiar winner. These results suggest that a defeat during an interaction with one male affects later agonistic behavior towards other, unfamiliar males [Current Zoology 57 （4）： 449-452, 2011].

关键词： Agonistic behavior loser Hamsters Mesocricetus

SO(n)-Invariant Special lagrangian Submanifolds of C^(n+1) with Fixed loci

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Chinese Annals of Mathematics,Series B 2006年第1期27卷 95-112页

作者： robert l. BRYANT Dedicated to the memory of Shiing-Shen Chern

let SO（n） act in the standard way on C^n and extend this action in the usual way to C^n＋l = C＋ C^n. It is shown that a nonsingular special lagrangian submanifold l→∪ C^n＋l that is invariant under this SO（n）-action intersects the fixed C→∪ C^n＋1 in a nonsingular real-analytic arc A （which may be empty）. If n 〉 2, then A has no compact component. Conversely, an embedded, noncompact nonsingular real-analytic arc A→∪ C lies in an embedded nonsingular special lagrangian submanifold that is SO（n）-invariant. The same existence result holds for compact A if n =2. nonsingular SO（n）-invariant special lagrangian nonsingular SO（n）-invariant special lagrangian extensions in some open neighborhood of A. If A is connected, there exist n distinct extensions of A such that any embedded extension of A agrees with one of these n The method employed is an analysis of a singular nonlinear PDE and ultimately calls on the work of Gerard and Tahara to prove the existence of the extension.

关键词： Calibrations Special lagrangian submanifolds

Boundary element method (BEM) applied to the rough surface contact vs. BEM in computational mechanics

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Friction 2019年第4期7卷 359-371页

作者： Yang XU robert l.JACKSON Mechanical Engineering Department Auburn University

In the numerical study of rough surfaces in contact problem, the flexible body beneath the roughness is commonly assumed as a half-space or a half-plane. The surface displacement on the boundary, the displacement components and state of stress inside the half-space can be determined through the convolution of the traction and the corresponding influence function in a closed-form. The influence function is often represented by the Boussinesq-Cerruti solution and the Flamant solution for three-dimensional elasticity and plane strain/stress, respectively. In this study, we rigorously show that any numerical model using the above mentioned half-space solution is a special form of the boundary element method(BEM). The boundary integral equations(BIEs) in the BEM is simplified to the Flamant solution when the domain is strictly a half-plane for the plane strain/stress condition. Similarly, the BIE is degraded to the Boussinesq-Cerruti solution if the domain is strictly a half-space. Therefore, the numerical models utilizing these closed-form influence functions are the special BEM where the domain is a half-space(or a half-plane). This analytical work sheds some light on how to accurately simulate the non-half-space contact problem using the BEM.

关键词： boundary element method rough surface contact half-space half-plane Flamant solution Boussinesq-Cerruti solution

Genetic basis for body size variation between an anadromous and two derived lacustrine populations of threespine stickleback Gasterosteus aculeatus in southwest Alaska

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Current Zoology 2016年第1期62卷 71-78页

作者： Ella BOWlES Rebecca A. johnston Stevi l. VANDERZWAN Sean M. ROGERS Department of Biological Sciences University of Calgary 2500 University Dr. N.W. Calgary Alberta T2N 1N4Canada

Body size is a highly variable trait among geographically separated populations. Size-assortative reproductive isolation has been linked to recent adaptive radiations of threespine stickleback （Gasterosteus aculeatus） into freshwater, but the genetic basis of the commonly found size differ- ence between anadromous and derived lacustrine sticklebacks has not been tested. We studied the genetic basis of size differences between recently diverging stickleback lineages in southwest Alaska using a common environment experiment. We crossed stickleback within one anadromous （Naknek River） and one lake （Pringle lake） population and between the anadromous and two lake populations （Pringle and JoJo lakes）, and raised them in a salinity of 4-6 ppt. The F1 anadromous and freshwater forms differed significantly in size, whereas hybrids were intermediate or exhibited dominance toward the anadromous form. Additionally, the size of freshwater Fls differed from their wild counterparts, with within-population Fls from Pringle lake growing larger than their wild counterparts, while there was no size difference between lab-raised and wild anadromous fish. Sexual dimorphism was always present in anadromous fish, but not in freshwater, and not always in the hybrid crosses. These results, along with parallel changes among anadromous and fresh- water forms in other regions, suggest that this heritable trait is both plastic and may be under di- vergent and/or sexual selection.

关键词： adaptation body size common garden genetic basis threespine stickleback.

Changes in particulate and mineral-associated organic carbon with land use in contrasting soils

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Pedosphere 2023年第3期33卷 421-435页

作者： Sabina YEASMIN Balwant SINGH Cliff T.johnston Quan HUA Donald l.SPARKS Sydney Institute of Agriculture School of Life and Environmental SciencesThe University of SydneySydney NSW 2006(Australia) Department of Agronomy Bangladesh Agricultural UniversityMymensingh-2202(Bangladesh) Crop Soil and Environmental SciencesPurdue UniversityWest Lafayette IN 47907(USA) Australian Nuclear Science and Technology Organisation Locked Bag 2001Kirrawee DC NSW 2232(Australia) Department of Plant and Soil Sciences University of DelawareNewark DE 19716(USA)

Soil organic carbon(SOC)is the largest terrestrial carbon(C)stock,and the capacity of soils to preserve organic C(OC)varies with many factors,including land use,soil type,and soil *** investigated the effect of land use change on soil particulate organic matter(POM)and mineral-associated organic matter(MOM).Surface(0–10 cm)and subsurface(60–70 cm)samples were collected from paired sites(native and cropped)of four contrasting *** soils were separated into POM and MOM fractions,which were analyzed for mineralogy,OC,nitrogen,isotopic signatures,*** POM fractions of surface soils were relatively unaffected by land use change,possibly because of the continuous input of crop residues,whereas the POM fractions in corresponding subsurface soils lost more *** surface soils,MOM fractions dominated by the oxides of iron and aluminum(oxide-OM)lost more OC than those dominated by phyllosilicates and quartz,which was attributed to diverse organic matter(OM)input and the extent of OC saturation limit of *** contrast,oxide-OM fractions were less affected than the other two MOM fractions in the subsurface soils,possibly due to OC protection via organo-mineral *** deviations in isotopic signature(linked with vegetation)across the fractions suggested that fresh crop residues constituted the bulk of OM in surface soils(supported by greater14C).Increased isotopic signatures and lower14C in subsurface MOM fractions suggested the association of more microbially processed,aged OC with oxide-OM fractions than with the other MOM *** results reveal that the quantity and quality of OC after land use change is influenced by the nature of C input in surface soils and by mineral-organic association in subsurface soils.

关键词： land use change microbial decomposition organic carbon saturation organo-mineral association soil organic matter

Genetic and molecular changes in ovarian cancer

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Cancer Biology & Medicine 2016年第2期13卷 236-247页

作者： robert l Hollis Charlie Gourley Edinburgh Cancer Research UK Centre MRC Institute of Genetics and Molecular Medicine University of Edinburgh

Epithelial ovarian cancer represents the most lethal gynecological malignancy in the developed world, and can be divided into five main histological subtypes: high grade serous, endometrioid, clear cell, mucinous and low grade serous. These subtypes represent distinct disease entities, both clinically and at the molecular level. Molecular analysis has revealed significant genetic heterogeneity in ovarian cancer, particularly within the high grade serous subtype. As such, this subtype has been the focus of much research effort to date, revealing molecular subgroups at both the genomic and transcriptomic level that have clinical ***, stratification of ovarian cancer patients based on the underlying biology of their disease remains in its infancy. Here, we summarize the molecular changes that characterize the five main ovarian cancer subtypes, highlight potential opportunities for targeted therapeutic intervention and outline priorities for future research.

关键词： ovarian cancer molecular genetics histological subtypes molecular subgrouping ovary

Assessment of portable FTIR and Raman spectroscopy for the detection of 2,3-dimethyl-2,3-dinitrobutane(DMDNB)in plastic explosives

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Defence Technology（防务技术） 2024年第4期34卷 11-18页

作者： Jacky Cailes robert Dunsmore Kathryn l.linge ChemCentre PO Box 1250PerthAustralia

The Marplex Convention was established to prevent the manufacture of unmarked plastic explosives and stipulates that a volatile detection agent must be added at the time of ***,to-date,laboratory testing remains the internationally accepted practice for identifying and quantifying the taggants stipulated in the *** this project,portable FTIR and Raman instruments were tested for their ability to detect 2,3-dimethyl-2,3-dinitrobutane(DMDNB),the chemical marker incorporated in plastic explosives that are manufactured within *** both FTIR and Raman instruments detected solid DMDNB(98%purity),field analysis of plastic explosives at an Australian Defence establishment showed that both FTIR and Raman spectra were matched the relevant explosive(RDX or PETN),rather than the DMDNB *** all three plastic explosives tested,the concentration of DMDNB was measured by SPME-GC-MS to be between 1.8 and 2%,greater than the minimum 1%concentration stipulated by the Marplex *** testing with a plastic explosive analogue confirmed that the minor absorption peaks that would characterize low concentrations of DMDNB were masked by absorption bands from other compounds within the ***,while both FTIR and Raman spectroscopy are suitable for detection of plastic explosives,neither rely on the presence of DMDNB for *** is likely that similar results would be found for other taggants stipulated by the Marplex Convention,given they are also present in concentrations less than 1%.

关键词： Explosive ICAO taggants 2,3-Dimethyl-2,3-dinitrobutane(DMDNB) Fourier transform infrared(FTIR) Raman

Rapid recovery of rare earth elements in industrial wastewater by CuFe_2O_4 synthesized from Cu sludge

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Journal of Rare Earths 2018年第5期36卷 513-520页

作者： Yao-Jen Tu Cliff T.johnston Institute of Urban Study Shanghai Normal University Shanghai 200234 China Crop Soil and Environmental Sciences Purdue University 915 W. State Street West Lafayette IN 47907 USA

This study systematically evaluates the recovery of rare earth elements（REEs） from aqueous solution and industrial wastewater using magnetic nanoparticles CuFe2O4. The industrially manufactured CuFe2O4 displays a nonlinear isotherm for REEs adsorption, suggesting limiting binding sites on the CuFe2O4 surface. The recovery of REEs increases significantly from 0.1% to 99.99% with increasing pH（2.29-8.15）. At room temperature, the maxima recovery rates of Nd, la, and Ce are observed to be in a high capacity of 51.02, 42.02, and 40.16 mg/g, respectively. No significant attenuation of REE adsorption is observed with increasing NaCl concentration from 0.001 to 1.0 mol/l, showing high selectivity of REEs even in such high NaCl concentration matrix. In addition, desorption efficiency increases with the increasing concentration of HNO3 in the range of 0.005-0.05 mol/l. When HNO3 concentration is over 0.05 mol/l, the desorption efficiency can reach almost 100% in each batch experiment. Importantly, our results show that REEs can be sorbed and recycled from liquid crystal display（lCD） polishing wastewater, suggesting that CuFe2O4 may be a good candidate in the efficient and rapid recovery of REEs from industrial wastewater.

关键词： Rare earth elements Industrial wastewater Industrial sludge Magnetic separation CuFe2O4

The influence of various grease compositions and silver nanoparticle additives on electrically induced rolling-element bearing damage

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Friction 2024年第4期12卷 796-811页

作者： Samuel BOND robert l.JACKSON German MIllS Department of Chemistry and Biochemistry Auburn UniversityAuburn 36849-5412USA Department of Mechanical Engineering Auburn UniversityAuburn 36849-5412USA

leakage currents accelerate surface degradation of metal contacts via small scale arcing across lubricating films,but recent observations suggest that metallic nanoparticle additives in lubricants may be useful to improve contact *** findings prompted a study that examined electrically induced surface pitting of steel contacts in the presence of several lubricating greases including some containing nanometer-sized colloidal silver(Ag)*** rolling sphere-on-disk experiments were conducted under electro-tribological loads employing polyurea greases derived from mineral and synthetic base oils with and without *** forces and electrical resistance were monitored continuously during the tests;surface changes were characterized by means of optical spectroscopy,stylus profilometry,and scanning electron microscopy(SEM)including compositional analysis using energy dispersive spectroscopy(EDS).The observations demonstrate that surface pitting induced by arcing occurs mainly at the points were the rolling motion changes direction and that eroded metal is deposited along the wear ***-sized pits are formed which contain carbon and oxygen indicating that arcing causes decomposition of the hydrocarbon *** findings indicate a significant inhibition of pitting is induced by the Ag nanoparticles;some greases containing other additives exhibit a similar,although less pronounced,effect.

关键词： electric motor bearings wheel bearings electric vehicles arcing electrically induced bearing damage pitting leakage current stray current