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chemistry of sediments from the Dobczyce Reservoir,Poland,and the environmental implications

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International Journal of Sediment Research 2010年第1期25卷 28-38页

作者： Witold REcZYNSKI Malgorzata JAKUBOWSKA Janusz GOLAS Andrew parker Barbara KUBIcA University of Science and Technology University of Reading Institute of Nuclear Physics

Sediments samples of the Dobczyce Reservoir(South Poland) were taken in three successive years(2004-06) at 17 points,analyzed for 12 elements by atomic absorption *** variations in elemental composition due to hydrological and environmental reasons were *** use of statistical and chemometric tools enabled objective and effective analysis of the data obtained,both in case of long term observations as well as in terms of interpretation of incidental changes in metal *** proposed methodology can be useful in:a) dividing monitored territories(lakes,rivers,catchments) into similar and dissimilar areas;b) distinguishing between typical and non-typical contaminants distribution;c) reducing the number of essential analytes and sampling points that should be controlled in the future,without loss of important environmental information.

关键词： Dobczyce Reservoir Sediments Metals cA PcA

Stem cell therapy for the treatment of Leydig cell dysfunction in primary hypogonadism

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World Journal of Stem cells 2016年第10期8卷 306-315页

作者： Taylor c Peak Nora M Haney william Wang Kenneth J DeLay Wayne J Hellstrom Department of Urology School of MedicineTulane University

The production of testosterone occurs within the Leydig cells of the testes. When production fails at this level from either congenital, acquired, or systemic disorders,the result is primary hypogonadism. While numerous testosterone formulations have been developed, none are yet fully capable of replicating the physiological patterns of testosterone secretion. Multiple stem cell therapies to restore androgenic function of the testes are under investigation. Leydig cells derived from bone marrow, adipose tissue, umbilical cord, and the testes have shown promise for future therapy for primary hypogonadism. In particular, the discovery and utilization of a group of progenitor stem cells within the testes, known as stem Leydig cells(SLcs), has led not only to a better understanding of testicular development, but of treatment as well. When combining this with an understanding of the mechanisms that lead to Leydig cell dysfunction, researchers and physicians will be able to develop stem cell therapies that target the specific step in the steroidogenic process that is deficient. The current preclinical studies highlight the complex nature of regenerating this steroidogenic process and the problems remain unresolved. In summary, there appears to be two current directions for stem cell therapy in male primary hypogonadism. The first method involves differentiating adult Leydig cells from stem cells of various origins from bone marrow, adipose, or embryonic sources. The second method involves isolating, identifying, and transplanting stem Leydig cells into testicular tissue. Theoretically, in-vivo re-activation of SLcs in men with primary hypogonadism due to age would be another alternative method to treat hypogonadism while eliminating the need for transplantation.

关键词： Stem cell therapy Leydig cells Primary hypogonadism Stem Leydig cells Testosterone Bone marrow-derived stem cells Adipose-derived mesenchymal stem cells

Ramanujan-type congruences for broken 2-diamond partitions modulo 3

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Science china Mathematics 2014年第8期57卷 1553-1560页

作者： cHEN william Y.c. FAN Anna R.B. YU Rebecca T. center for Applied Mathematics Tianjin University center for combinatorics LPMC-TJKLC Nankai University

The notion of broken k-diamond partitions was introduced by Andrews and ***△k(n)denote the number of broken k-diamond partitions of *** and Paule also posed three conjectures on the congruences of△2(n)modulo 2,5 and *** and Sellers proved the conjectures for modulo 2,and chan proved the two cases of modulo *** the case of modulo 3,Radu and Sellers obtained an infinite family of congruences for△2(n).In this paper,we obtain two infinite families of congruences for△2(n)modulo 3 based on a formula of Radu and Sellers,a 3-dissection formula of the generating function of triangular number due to Berndt,and the properties of the U-operator,the V-operator,the Hecke operator and the Hecke *** example,we find that△2(243n+142)≡△2(243n+223)≡0(mod 3).The infinite family of Radu and Sellers and the two infinite families derived in this paper have two congruences in common,namely,△2(27n+16)≡△2(27n+25)≡0(mod 3).

关键词： broken k-diamond partition modular form Ramanujan-type congruence Hecke eigenform

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Variable High-Order Multiblock Overlapping Grid Methods for Mixed Steady and Unsteady Multiscale Viscous Flows,Part II:Hypersonic Nonequilibrium Flows

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communications in computational Physics 2013年第2期13卷 583-602页

作者： Andrea Lani Björn Sjögreen H.c.Yee william D.Henshaw NASA Ames/Stanford centre for Turbulence Research Palo AltoCAUSA Lawrence Livermore National Laboratory LivermoreCAUSA MS 258-5 NASA Ames Research CenterMoffett FieldCAUSA

The variable high-order multiblock overlapping(overset)grids method of Sj¨ogreen&Yee[cicP,Vol.5,2009]for a perfect gas has been extended to nonequilibrium *** work makes use of the recently developed high-order well-balanced shock-capturing schemes and their filter counterparts[Wang et al.,***.,2009,2010]that exactly preserve certain non-trivial steady state solutions of the chemical nonequilibrium governing *** turbulence with strong shocks and flows containing both steady and unsteady components is best treated by mixing of numerical methods and switching on the appropriate scheme in the appropriate subdomains of the flow fields,even under the multiblock grid or adaptive grid refinement *** low dissipative sixth-or higher-order shock-capturing filter methods are appropriate for unsteady turbulence with shocklets,second-and thirdorder shock-capturing methods are more effective for strong steady or nearly steady shocks in terms of *** is anticipated that our variable high-order overset grid framework capability with its highly modular design will allow for an optimum synthesis of these new algorithms in such a way that the most appropriate spatial discretizations can be tailored for each particular region of the *** this paper some of the latest developments in single block high-order filter schemes for chemical nonequilibrium flows are applied to overset grid *** numerical approach is validated on a number of test cases characterized by hypersonic conditions with strong shocks,including the reentry flow surrounding a 3D Apollo-like NASA crew Exploration Vehicle that might contain mixed steady and unsteady components,depending on the flow conditions.

关键词： Unstructured mesh hypersonic flows thermo-chemical nonequilibrium residual distribution schemes double cone

Modular next generation fast-neutron detector for portal monitoring

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Nuclear Science and Techniques 2022年第1期33卷 140-148页

作者： E.Aboud S.Ahn G.V.Rogachev V.E.Johnson J.Bishop G.christian E.Koshchiy c.E.parker D.P.Scriven cyclotron Institute Texas A&M UniversityCollege StationTX 77843USA Department of Physics and Astronomy Texas A&M UniversityCollege StationTX 77843USA Department of Statistics Texas A&M UniversityCollege StationTX 77843USA

Nuclear nonproliferation is of critical importance for global *** fissile materials including highly enriched uranium and weapons-grade plutonium are especially important to *** interrogation techniques may result in much better sensitivity but are difficult with conventional portal monitors that rely on detecting thermal ***,most conventional portal monitoring systems rely on ^(3)He,which has a finite and continually decreasing *** designing a highly segmented array of organic scintillators,we posit that we can accurately and quickly identify fissile materials,including weapons-grade plutonium and highly enriched uranium,being *** propose a new design for a fast-neutron detector that overcomes the limitations of the current generation of portal ***6 simulations have been performed in conjunction with the UMPBT statistical model to determine the sensitivity limitations of the proposed *** suggest that the proposed detector may be 10 times more efficient than current-generation thermal neutron detectors and may be able to positively identify a 81 mg 235U source in as little as 192 seconds utilizing active interrogation techniques.

关键词： Fast-neutron detection Portal monitoring Nonproliferation

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Exchange-correlation Functional comparison of Electronic Energies in Atoms Using a Grid Basis

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Journal of Applied Mathematics and Physics 2022年第11期10卷 3392-3407页

作者： Anthony D. Ryan Andres Gama Frank Felerski william D. parker Department of Mathematics and Physics University of Wisconsin-Parkside Kenosha WI USA

calculation of total energies of the electronic ground states of atoms forms the basis for the frozen-core pseudopotentials used in atomistic calculations of much larger scale. Reference values for these energies provide a benchmark for the validation of new software to calculate such potentials. In addition, basic atomic-scale electronic properties such as the (first) ionization energy provide a simple check on the approximation used in the calculation method. We present a comparison of the total energies and ionization energies of atoms Z = 1 - 92 calculated in density functional theory with several levels of exchange-correlation functional and the Hartree-Fock method, comparing ionization energies to experiment. We also investigate the role of relativistic treatment on these energies.

关键词： Density Functional Theory Hartree-Fock Theory Electronic Energies Exchange-correlation Potential Exchange and correlation Functional Ionization Energy

The changing pattern of renal osteodystrophy

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肾脏病与透析肾移植杂志 1996年第2期 1-9+95页

作者： Allen c.Alfrey william E.Huffer Department of Medicine and Pathology Denver V.A.Medical center and University of colorado Health Sciences center USA Department of Medicine and Pathology Denver V.A.Medical center and University of colorado Health Sciences center USA

Aluminum intoxication has been a ma-jor cause of morbidity and mortality in dia-lyzed uremic *** the last 7-years means to markedly reduce aluminumexposure in this population have been *** study was carried out to de-termine how effective restriction of alu-minum exposure has been in preventing alu-minum loading and toxicity in uremic *** All bone histology processed onpatients with end-stage renal disease(452patients)between January 1984 and Decem-ber 1991 were *** were performed and bones dividedinto four major grouping:①high turnover,osteitis firosa;②low turnover,osteomala-cia;③low turnover,adynamic and ④mixedtype bone *** Between 1985 and 1991 a signifi-cant decrease in aluminum loading wasfound in patients with end-stage renal dis-ease as determined by a fall in plasma alu-minum from 74±30 μg/L to 12±7 μg/L and decrease in aluminum positive bonespecimens from 87.2% to 35.8%(Pction in aluminumloading low turnover osteomalacic bone dis-ease decreased from 11.6% to less than 5%(Pcimensstudied and the fraction of mixed bone dis-ease with osteomalacic features decreasedfrom 33% to 19%(Pchange in the other types of bone *** The present methods of limit-ing aluminum exposure in dialysis patientsappears to be fairly effective in preventingaluminum loading and skeletal toxicity,manifested as a mineralization ***-ever,aluminum restriction had no influenceon high turnover bone disease or the ady-namic type of low turnover disease support-ing a different etiology for these two typesof bone disease.

关键词： aluminum uremia osteomalacia hyperparathyroid bone

Targeting DNA topoisomerases: past & future

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cancer Drug Resistance 2021年第4期4卷 758-761页

作者： william H.Gmeiner Robert c.A.Mvan Waardenburg Department of cancer Biology Wake Forest School of Medicine Medical Center BlvdWinston-SalemNC 27157USA Department of Pharmacology and Toxicology University of Alabama at BirminghamBirminghamAL 35294-0019USA

Aggressive malignancies are characterized by relatively uncontrolled cell proliferation making them especially reliant on topoisomerase enzymes to enable high rates of DNA replication and *** topoisomerases resolve topological problems associated with DNA replication and other essential cellular processes involving DNA,such as transcription and recombination^([1]).As such,they are important targets for anti-cancer ***,understanding of topoisomerase biology is important for unraveling the mechanistic basis for resistance to many widely used anti-cancer drugs,such as doxorubicin,etoposide,and topotecan,for which DNA topoisomerases are established ***,several drugs that are not considered to directly target topoisomerase enzymes,such as the nucleoside analogs 5-FU and Arac,and those in development such as the polymeric fluoropyrimidine cF10^([2]),also affect the function of topoisomerases.

关键词： analogs topological enable

Microstructural Evolution of Nb–V–Mo and V containing TRIP-assisted Steels during Thermomechanical Processing

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Journal of Materials Science & Technology 2017年第4期33卷 311-320页

作者： Erfan Abbasi william Mark Rainforth Department of Materials Science and Engineering The University of Sheffield

The microstructural evolution and precipitation behaviour of Nb–V–Mo and single V containing transformation induced plasticity assisted steels were investigated during thermomechanical processing. A plane strain compression testing machine was used to simulate the thermomechanical processing. Microstructures were characterised by optical microscopy, scanning-transmission electron microscopy and microanalysis, and X-ray diffraction analysis, and Vickers hardness was obtained from the deformed specimens. The resulting microstructure of both Nb–V–Mo and V steels at room temperature primarily consisted of an acicular/bainitic ferrite, retained austenite and martensite surrounded by allotriomorphic *** TEM analysis showed that a significant number of Nb（V,Mo）（c,N） precipitates were formed in the microstructure down to the finishing stage in Nb–V–Mo steel（i.e. 830℃）. It was also found that the V（c,N）precipitation primarily occurred in both ferrite and deformed austenite below the finishing stage. The results suggested that Nb–Mo additions considerably increased the temperature stability of microalloy precipitates and controlled the microstructural evolution of austenite. However, the microalloy precipitation did not cause a significant precipitation strengthening in both Nb–V–Mo and V steels at room temperature.

关键词： Microalloyed TRiP-assisted steel Thermomechanical processing Precipitation behaviour Microstructural evolution

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