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Nano-and micron-sized diamond genesis in nature:An overview

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Geoscience Frontiers 2018年第6期9卷 1849-1858页

作者： s.k.simakov LLC“ADAMANT”skolkovo Harchenko 19-A-7HSt.Petersburg194100Russia

There are four main types of natural diamonds and related formation processes. The first type comprises the interstellar nanodiamond particles. The second group includes crustal nano-and micron-scale diamonds associated with coals, sediments and metamorphic rocks. The third one includes nanodiamonds and microndiamonds associated with secondary alteration and replacing of mafic and ultramafic *** fourth one includes macro-, micron-and nano-sized mantle diamonds which are associated with kimberlites, mantle peridotites and eclogites. Each diamond type has its specific characteristics. Nanosized diamond particles of lowest nanometers in size crystallize from abiotic organic matter at lower pressures and temperatures in space during the stages of protoplanetary disk formation. Nano-sized diamonds are formed from organic matter at P-T exceeding conditions of catagenesis stage of lithogenesis. Micron-sized diamonds are formed from fluids at P-T exceeding supercritical water *** diamonds are formed from metal-carbon and silicate-carbonate melts and fluids at P-T exceeding 1150℃ and 4.5 GPa. Nitrogen and hydrocarbons play an important role in diamond *** role in the formation processes increases from macro-sized to nano-sized diamond *** of nitrogen atoms into the diamond structure leads to the stabilization of micron-and nanosized diamonds in the field of graphite stability.

关键词： Diamond Nanodiamonds sediments Meteorites Mantle Organics

Isolation and characterization of mesenchymal stem cells in orthopaedics and the emergence of compact bone mesenchymal stem cells as a promising surgical adjunct

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World Journal of stem Cells 2020年第11期12卷 1341-1353页

作者： albert Anastasio Marina Gergues Michael s Lebhar Pranela Rameshwar Joseph Fernandez-Moure Department of Orthopedic surgery Duke University Health SystemDurhamNC 27710United States Department of Medicine Hematology/OncologyRutgers UniversityNew Jersey Medical SchoolNewarkNJ 07103United States school of Medicine Duke University School of MedicineDurhamNC 27710United States Department of Medicine-Hematology/Oncology Rutgers School of Biomedical Health ScienceNewarkNJ 07103United States Department of surgery Division of TraumaAcuteand Critical Care SurgeryDuke University School of MedicineDurhamNC 27710United States

The potential clinical and economic impact of mesenchymal stem cell(MsC)therapy is *** act through multiple pathways:(1)as“trophic”cells,secreting various factors that are immunomodulatory,anti-inflammatory,antiapoptotic,proangiogenic,proliferative,and chemoattractive;(2)in conjunction with cells native to the tissue they reside in to enhance differentiation of surrounding cells to facilitate tissue *** have developed methods for the extraction and expansion of MsCs from animal and human *** many sources of MsCs exist,including adipose tissue and iliac crest bone graft,compact bone(CB)MsCs have shown great potential for use in orthopaedic *** MsCs exert powerful immunomodulatory effects in addition to demonstrating excellent regenerative capacity for use in filling boney *** MsCs have been shown to have enhanced response to hypoxic conditions when compared with other forms of *** work is needed to continue to characterize the potential applications for CB MsCs in orthopaedic trauma.

关键词： Compact bone Mesenchymal stem cells stem cells Trauma Orthopedic Regeneration

Effect of NO_3^--N Enrichment on seawater stress Tolerance of Jerusalem Artichoke (Helianthus tuberosus)

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Pedosphere 2008年第1期18卷 113-123页

作者： s.k.MEHTA College of Resources and Environmental sciences Nanjing Agricultural University

A hydroponic experiment with six treatments, i.e., 0% seawater （control）, 10% seawater, 25% seawater, 0% seawater ＋ N （7.5 mmol L-1 NaNO3）, 10% seawater ＋ N （7.5 mmol L-1 NaO3）, and 25% seawater ＋ N （7.5 mmol L-1 NaNO3）, was carried out to study the effect of nitrogen addition on the growth and physiological and biochemical characteristics of Jerusalem artichoke （Helianthus tuberosus） seedlings under seawater stress. The 10% seawater stress treatment had the least effect on plant growth while at 25% seawater growth was significantly inhibited. The malondialdehyde content and electrolyte leakage in leaves under 10% seawater were similar to those of the control, but significantly higher under the 25% seawater stress. The activities of superoxide dismutase, peroxidase and catalase in the leaves increased concomitantly with increasing seawater concentration and time. Proline and soluble-sugars in the leaves and Na^＋, k^＋, and Cl- contents in shoots and roots increased significantly with the concentration of seawater increasing. Nitrogen addition resulted in increasing fresh and dry weights of shoots and roots compared with seawater treatment without N. Nitrogen supplementation also significantly enhanced the activities of antioxidant enzymes in leaves. Addition of N to seawater enhanced the contents of proline and soluble-sugars in the leaves and k^＋ and total-N in the aerial parts and roots of H. tuberosus, but it resulted in declined concentrations of Na^＋ and Cl- in the aerial parts and roots. Nitrogen addition ameliorated the toxicity of seawater by improving the antioxidative enzymes, accumulating of proiine and soluble-sugars, and altering the distribution of inorganic ions in H. tuberosus.

关键词： Helianthus tuberosus ions distributions malondialdehyde nitrate seawater stress

The Fibered Isomorphism Conjecture for Complex Manifolds

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Acta Mathematica sinica,English series 2007年第4期23卷 639-658页

作者： s.k.ROUsHON school of Mathematics Tata InstituteHomi Bhabha RoadMumbai 400 005India

In this paper we show that the Fibered Isomorphism Conjecture of Farrell and Jones, corresponding to the stable topological pseudoisotopy functor, is true for the fundamental groups of a class of complex manifolds. A consequence of this result is that the Whitehead group, reduced projective class groups and the negative k-groups of the fundamental groups of these manifolds vanish whenever the fundamental group is torsion free. We also prove the same results for a class of real manifolds including a large class of 3-manifolds which has a finite sheeted cover fibering over the circle.

关键词： Complex projective variety Complex surfaces Whitehead group Fibered isomorphism conjecture Negative k-groups

Combustion synthesis and luminescence characteristic of rare earth activated LiCaBO_3

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Journal of Rare Earths 2012年第10期30卷 1005-1008页

作者： N.s. Bajaj s.k. Omanwar Department of Physics SGB Amravati University Amravati-444602 (M.S.)

Lithium calcium borate （LiCaBO3） polycrystalline thermoluminescence （TL） phosphor doped with rare earth （Tb3＋ and Dy3＋） elements was synthesized by novel solution combustion synthesis. The reaction produced very stable crystalline LiCaBO3：D（D=Tb3＋ and Dy3＋） phosphors. These rare earth doped phosphors material showed maximum TL sensitivity with favorable glow curve shape. TL glow curve of X-ray irradiated that LiCaBO3：Tb3＋ and LiCaBO3：Dy3＋ samples showed two major well-separated glow peaks. The TL sensitivity of these phosphors to X-ray radiation was comparable with that of TLD-100（Harshaw）. Photoluminescence spectra of LiCaBO3：Tb3＋ and LiCaBO3：Dy3＋ showed the characteristic Tb3＋ and Dy3＋ peaks respectively. TL response to X-ray radiation dose was linear up to 25 Gy.

关键词： luminescence LiCaBO3 combustion synthesis rare earths kinetics

Examining pathogenic concepts of autoimmune hepatitis for cues to future investigations and interventions

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World Journal of Gastroenterology 2019年第45期25卷 6579-6606页

作者： albert J Czaja Division of Gastroenterology and Hepatology Mayo Clinic College of Medicine and Science

BACkGROUND Multiple pathogenic mechanisms have been implicated in autoimmune hepatitis,but they have not fully explained susceptibility,triggering events,and maintenance or escalation of the ***,they have not identified a critical defect that can be *** goals of this review are to examine the diverse pathogenic mechanisms that have been considered in autoimmune hepatitis,indicate investigational opportunities to validate their contribution,and suggest interventions that might evolve to modify their *** abstracts were identified in PubMed by multiple search *** length articles were selected for review,and secondary and tertiary bibliographies were *** and epigenetic factors can affect susceptibility by influencing the expression of immune regulatory *** dysfunction,possibly related to deficient production of programmed cell death protein-1,can allow autoreactive T cells to escape deletion,and alterations in the intestinal microbiome may help overcome immune tolerance and affect gender *** factors may trigger the disease or induce epigenetic changes in gene *** mimicry,epitope spread,bystander activation,neo-antigen production,lymphocytic polyspecificity,and disturbances in immune inhibitory mechanisms may maintain or escalate the *** that modify epigenetic effects on gene expression,alter intestinal dysbiosis,eliminate deleterious environmental factors,and target critical pathogenic mechanisms are therapeutic possibilities that might reduce risk,individualize management,and improve *** conclusion,diverse pathogenic mechanisms have been implicated in autoimmune hepatitis,and they may identify a critical factor or sequence that can be validated and used to direct future management and preventive strategies.

关键词： Autoimmune hepatitis Pathogenesis Epigenetics Molecular mimicry Epitope spread Intestinal microbiome

Hepatic inflammation and progressive liver fibrosis in chronic liver disease

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World Journal of Gastroenterology 2014年第10期20卷 2515-2532页

作者： albert J Czaja Division of Gastroenterology and Hepatology Mayo Clinic College of Medicine Rochester MN 55905 United States

Chronic liver inflammation drives hepatic fibrosis,and current immunosuppressive,anti-inflammatory,and anti-viral therapies can weaken this *** fibrosis is reversed,stabilized,or prevented in 57%-79%of patients by conventional treatment regimens,mainly by their anti-inflammatory ***,however,are commonly incomplete and inconsistently *** fibrotic mechanisms associated with liver inflammation have been clarified,and anti-fibrotic agents promise to improve outcomes as adjunctive *** C virus and immune-mediated responses can activate hepatic stellate cells by increasing oxidative stress within *** can be synthesized by activated hepatic stellate cells and promote the production of reactive oxygen ***-oxidants(Nacetylcysteine,s-adenosyl-L-methionine,and vitamin E)and angiotensin inhibitors(losartin)have had antifibrotic actions in preliminary human studies,and they may emerge as supplemental ***-fibrotic agents presage a new era of supplemental treatment for chronic liver disease.

关键词： Inflammation Fibrosis Cirrhosis Treatment Anti-oxidants Angiotensin receptors Investigational drugs

Mindless Intelligence Method for solving the Tower of Hanoi Problem

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Chinese Journal of Mechanical Engineering 2009年第2期22卷 159-168页

作者： TsAU Minhe kAO Weiwen CHANG albert Department of Mechanical Engineering Taiwan University of Science and Technology Taipei 10607 Taiwan China Department of Industrial Management Vanung University of Science and Technology Taipei 32061 Taiwan China

Over the past years, more and more attention has been paid to artificial life research. The main object of artificial life research is to explore how to control the environments in which the digital organisms imitating natural life, under complicated competition and evolutionary conditions, develop their own wisdom, which can then be used to solve the problems in the real world. While most of the current researches applied one or another artificial life method to solve real problems, the fundamental mechanism of the emerging process of artificial life is seldom addressed. The research works on genetic algorithms, although bearing fruitful results, could only be deemed as constituting a basic stage in the process of artificial life development. This study proposes a new method of employing artificial life, to complement the contents of the research of mindless intelligence, which is regarded as a bridge linking genetic algorithms to general artificial life. And two important concepts, key manipulating parameters and contribution function in its context, are proposed to expand the mindless intelligence applications, in order to pave the way for the optimal design of an artificial life method, in an attempt to fill the conceptual gap between genetic algorithms and artificial life, and consequently clarifying the artificial life mechanism. As a case study we applied these innovative methods to solve an open problem： the Tower of Hanoi, to attest to the feasibility of our approach, and we have achieved satisfactory results.

关键词： artificial life genetic algorithm artificial intelligence mindless intelligence tower of Hanoi problem key manipulating parameter

Characterization of Fe_3O_4/P(st-MPEO) Amphiphilic Magnetic Polymer Microspheres

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Chemical Research in Chinese Universities 2002年第4期18卷 458-461页

作者： CHAN albert s. C. YIP C. W. Open Laboratory of Chirotechnology and Department of Applied Biology and Chemical Technology Open Laboratory of Chirotechnology and Department of Applied Biology and Chemical Technology Hong Kong Polytechnic University Hong Kong P. R. ChinaHong Kong Polytechnic University Hong Kong P. R. China

Amphiphilic magnetic microspheres consisting of styrene and poly(ethylene oxide) macromonomer(MPEO) were prepared by dispersion copolymerization in the presence of Fe_3O_4 magnetic fluid in an ethanol/water medium. The sizes of the magnetic microspheres and their distribution were characterized by means of scanning electron microscopy(sEM). The surface morphology and the average surface roughness of the microspheres were investigated by virtue of atomic force microscopy(AFM). It was found that the microspheres exhibit microscopic phase-separate and the mean square surface roughness of the microspheres increases with increasing MPEO used in the copolymerization. The amphiphilic magnetic microspheres containing 0 4-3 5 mg/g hydroxyl groups could be prepared from MPEO with different concentrations and styrene.

关键词： Amphiphilic magnetic polymer Microsphere Copolymerization