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Collective Bands in the Neutron—Rich 110Ru Nucleus

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Chinese physics Letters 2003年第3期20卷 350-353页

作者：姜卓 j.H.hamilton 等 Departmentofphysics TsinghuaUniversityBeijing100084 Departmentofphysics VanderbiltUniversityNashvilleTN37235USA

High spin states in neutron-rich 110Ru nucleus have been investigated by measuring high-fold prompt γ-ray coincidence events of the spontaneous fission of 252Cf with the Gammasphere detector array. The ground-state b... 详细信息

High spin states in neutron-rich p>110p>Ru nucleus have been investigated by measuring high-fold prompt γ-ray coincidence events of the spontaneous fission of p>252p>Cf with the Gammasphere detector array. The ground-state band and the γ-vibrational band have been confirmed and extended with spin up to 18 and 13 , respectively. The other three side bands, two proposed as two-quasiparticle bands and one proposed as a four-quasiparticle band, have been observed for the first time. The possible configurations for the quasi-particle bands are discussed. The cranked shell model calculations show that p>110p>Ru nucleus may have oblate triaxial deformation with parameters β2 = -0.30 and γ = 24°, and the band crossing in the yrast band is due to the alignment of a pair of h11/2 neutrons.

关键词： Gamma rays

Collective Computation,Information Flow,and the Emergence of Hunter-Gatherer Small-Worlds

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journal of Social Computing 2022年第1期3卷 18-37页

作者： Marcus j.hamilton the Department of Anthropology University of Texas at San AntonioSan AntonioTX 78249USA.

Two key features of human sociality are anatomically complex brains with neuron-dense cerebral cortices,and the propensity to form complex social networks with *** brains and complex social networks facilitate flows of fitness-enhancing energy and information at multiple scales of social ***,we consider how these flows interact to shape the emergence of macroscopic regularities in hunter-gatherer macroecology relative to other mammals and non-human *** computation is the processing of information by complex adaptive systems to generate inferences in order to solve adaptive *** hunter-gatherer societies the adaptive problem is to resolve uncertainty in generative models used to predict complex environments in order to maximize inclusive *** macroecological solution is to link complex brains in social networks to form collective brains that perform collective *** developing theory and analyzing data,the author shows hunter-gatherers bands of~16 people,or~4 co-residing families,form the largest collective brains of any social ***,because individuals,families,and bands interact at multiple time scales,these fission-fusion dynamics lead to the emergence of the macroscopic regularities in hunter-gatherer macroecology we observe in cross-cultural *** results show how computation is distributed across spatially-extended social networks forming decentralized knowledge systems characteristic of hunter-gatherer *** flow of information at scales far beyond daily interactions leads to the emergence of small-worlds where highly clustered local interactions are embedded within much larger,but sparsely connected multilevel metapopulations.

关键词： complex adaptive systems hierarchically modular networks collective brains macroecology allometry mammals primates

Observation of Rotational Bands in Neutron—Rich ^106Mo Nucleus

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Chinese physics Letters 2002年第2期19卷 180-183页

作者：许瑞清 j.H.hamilton Departmentofphysics TsinghuaUniversityBeijing100084 Departmentofphysics VanderbiltUniversityNashvilleTN37235USA

The rotational bands up to a spin of 16h in the neutron-rich ^106Mo nucleus have been investigated by measuring high-fold prompt γ-ray coincidence events following spontaneous fission of 252Cf with a Gammasphere detector array. The ground-state band, the one-phonon and two-phonon γ-vibrational bands, as well as a quasi-particle band have been confirmed and expanded. The other four collective rotational bands, three proposed as two-quasi-particle bands and one proposed as a β-vibrational band, have been newly observed. The characteristics of these collective bands and the possible configurations for the quasi-particle bands are discussed.

关键词： Gamma rays

Restoring the gut microbiome for the treatment of inflammatory bowel diseases

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World journal of Gastroenterology 2014年第13期20卷 3468-3474页

作者： jessica R Allegretti Matthew j hamilton Division of Gastroenterology Brigham and Women’s Hospital and Harvard Medical SchoolBostonMA 02115United States

Fecal microbiota transplantation (FMT) is considered to be a highly successful therapy for recurrent and refractory Clostridium difficile infection (CDI) based on recent clinical trials. The pathogenesis of inflammatory bowel diseases (IBD) is thought to be due in part to perturbations in the gut microflora that disrupt homeostasis. FMT restores essential components of the microflora which could reverse the inflammatory processes observed in IBD. Case reports and series for the treatment of IBD by FMT have shown promise with regards to treatment success and safety despite the limitations of the reporting. Future studies will determine the optimal delivery and preparation of stool as well as the conditions under which the recipient will derive maximal benefit. The long term consequences of FMT with regards to infection, cancer, auto-immune, and metabolic diseases are not known and will require continued regulation and study. Despite these limitations, FMT may be beneficial for the treatment of ulcerative colitis and Crohn’s disease, particularly those with concurrent CDI or with pouchitis.

关键词： Crohn’ s, Ulcerative colitis, Microbiota, Fecal transplantation, Dysbiosis, pouchitis, Clostridium difficile, probiotic

Compositional complexity dependence of dislocation density and mechanical properties in high entropy alloy systems

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progress in Natural Science:Materials International 2020年第4期30卷 545-551页

作者： p.Thirathipviwat G.Song j.Bednarcik U.Kühn T.Gemming K.Nielsch j.Han Leibniz Institute of Solid State and Materials Research (IFW Dresden) Frontier Research Center for Applied Atomic Sciences Ibaraki University Division of Advanced Materials Engineering and Institute for rare metals Kongju National University Institute of physic Pavol Jozef Safarik University in Ko?ice Deutsches Elektronen-Synchrotron (DESY) Institute of Materials Science Technische Universit?t Dresden Institute of Applied physics Technische Universit?t Dresden Korea Institute for Rare Metals Korea Institute of Industrial Technology (KITECH)

This study focuses on a quantitative analysis of dislocation accumulation after cold plastic deformation and mechanical properties of Fe Ni Co Cr Mn and Ti Nb Hf Ta Zr high entropy alloys(HEAs) which are single phase fcc and bcc solid solutions, respectively. In order to study the role of compositional complexity from unary to quinary compositions on dislocation accumulation and mechanical properties after plastic deformation, the single solid solution phase forming sub-alloys of the two HEAs were investigated. All studied samples revealed a large plastic deformability under cold-rotary swaging process by 85–90% area reduction without intermediate annealing. The dislocation density of all studied samples, determined by Williamson-Hall method on synchrotron X-ray diffraction patterns, were between 1014-1015m-2dependent on the alloy composition. The level of dislocation density after plastic deformation is not only affected by the number of constituent element but the lattice distortion and intrinsic properties in terms of stacking fault energy, modulus misfit, and melting point also impact the dislocation storage. The level of dislocation density determines the level of mechanical properties because of a resistance to dislocation motions. The hardness and yield compressive strength of the studied samples are proportional to the level of dislocation density.

关键词： High entropy alloys Dislocation density Synchrotron XRD Mechanical properties

Gastrointestinal Behcet's disease:A review

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World journal of Gastroenterology 2015年第13期21卷 3801-3812页

作者： Wasseem Skef Matthew j hamilton Thurayya Arayssi Department of Medicine St.Elizabeth’s Medical CenterBostonMA 02135United States Division of Gastroenterology Brigham and Women’s Hospital and Harvard Medical SchoolBostonMA 02115United States Weill Cornell Medical College in Qatar Doha 24144Qatar

Beh?et's disease(BD) is an idiopathic, chronic, relapsing, multi-systemic vasculitis characterized by recurrent oral and genital aphthous ulcers, ocular disease and skin lesions. prevalence of BD is highest in countries along the ancient silk road from the Mediterranean basin to East Asia. By comparison, the prevalence in North American and Northern European countries is low. Gastrointestinal manifestations of Beh?et's disease are of particular importance as they are associated with significant morbidity and mortality. Although ileocecal involvement is most commonly described, BD may involve any segment of the intestinal tract as well as the various organs within the gastrointestinal system. Diagnosis is based on clinical criteria- there are no pathognomonic laboratory tests. Methods for monitoring disease activity on therapy are available but imperfect. Evidence-based treatment strategies are lacking. Different classes of medications have been successfully used for the treatment of intestinal BD which include 5-aminosalicylic acid, corticosteroids, immunomodulators, and anti-tumor necrosis factor alpha monoclonal antibody therapy. Like inflammatory bowel disease, surgery is reserved for those who are resistant to medical therapy. A subset of patients have a poor disease course. Accurate methods to detect these patients and the optimal strategy for their treatment are not known at this time.

关键词： Behget syndrome Behget disease Upper gastrointestinal tract Inflammatory bowel disease Lower gastrointestinal tract Ulcer

Softening of phonon spectra in metallic glasses

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npj Computational Materials 2016年第1期2卷 31-35页

作者： Reza Mahjoub Nicholas E hamilton Kevin j Laws Michael Ferry School of Materials Science and Engineering The University of New South WalesSydneyNSWAustralia

The vibrational spectra of a series of MgZnCa amorphous alloys were computed using density functional theory and implementing the small displacement *** atomic structures of the alloys were obtained by ab initio molecular dynamics *** vibrational thermodynamic properties were calculated as a function of temperature and,in particular,the specific heat at low temperature was approximated by temperature cubed based on the Debye *** computed the contribution of Mg vibrations to the specific heat and investigated the softening of Mg phonon spectra,where the maximum allowed vibrational frequency is lowered and highly collective diffusion processes are *** statistical correlation between the reported critical casting thickness of the alloys and softening of Mg phonons was *** calculations were performed for two distinctively different amorphous ZrTiCuAl alloys with large and small reported critical casting thickness,*** findings were consistent with those of the MgZnCa alloys.

关键词： alloys softening casting

Microstructural Evolution and Mechanical Behaviour of Metastable Cu-Zr-Co Alloys

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journal of Materials Science & Technology 2014年第6期30卷 584-589页

作者： S.pauly K.Kosiba p.Gargarella B.Escher K.K.Song G.Wang U.Kühn j.Eckert IFW Dresden Institut für Komplexe Materialien HelmholtzstraBe 20D-01069 Dresden Germany Laboratory for Microstructures Shanghai University TU Dresden Institut für WerkstoffwissenschaftD-01062 Dresden Germany

Three different Cu-Zr-Co alloys, namely Cu40Zr37.5Co22.5, Cu42.5Zr45Co12.5 and Cu49Zr49Co2, were obtained by rapid cooling. The microstructure and phase formation of as-cast rods with diameters of 2 mm are compared with those of the respective ingots. An increasing Co content stabilises the B2 CuZr phase and leads to the precipitation of a ternary Cu-Zr-Co phase. The variation of the cooling rate affects the size of the B2 dendrites as well as the volume fraction and the morphology of the interdendritic phases. The mechanical properties were determined in compression and all alloys show a certain plastic deformability despite the presence of several binary and ternary intermetallic phases. The deformation mechanisms are discussed on the basis of the microstructures and the constituent phases.

关键词： Bulk metallic glasses Microstructural evolution Mechanical behaviour

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New multi-phonon gamma vibrational bands in A～110 neutron-rich nuclei

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Science China(physics,Mechanics & Astronomy) 2011年第S1期54卷 44-48页

作者： hamilton j H RAMAYYA A V RASMUSSEN j O HWANG j K YEOH E Y Department of physics Vanderbilt University Nashville TN 37235 USA Lawrence Berkeley National Laboratory Berkeley CA 94720 USA Department of physics Tsinghua University Beijing 100084 China

The high spin states of neutron-rich 103Nb, 107Tc and 109Tc nuclei in A^110 region have been investigated by measuring prompt γ-γ-γ coincident measurements populated with the spontaneous fission of 252Cf with the Gammasphere detector array. In 103Nb, one-phonon K = 9/2 and two-phonon K = 13/2 γ-vibrational bands have been identified. In 107Tc and 109Tc, one-phonon K = 11/2 and two-phonon K = 15/2 γ-vibrational bands, in which the zero-phonon bands are based on K=7/2 excited states, have also been identified. The two-phonon bands are first observed in odd-Z nuclei. The characteristics for these band structures have been discussed.

关键词： high spin states neutron-rich nucleus γ-vibrational bands

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