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Frontiers of physics 2015年第3期10卷 1-28页

作者： ikaros i. Bigi Department of Physics University of Notre Dame du Lac Notre Dame IN 46556 USA

We know that our Universe is composed of only - 4.5% ＂known＂ matter; therefore, our understanding is incomplete. This can be seen directly in the case of neutrino oscillations （without even considering potential other universes）. Charm quarks have had considerable impact on our under- standing of known matter, and quantum chromodynamics （QCD） is the only local quantum field theory to describe strong forces. it is possible to learn novel lessons concerning strong dynamics by measuring rates around the thresholds of [Q^-Q] states with Q = b, c. Furthermore, these states provide us with gateways towards new dynamics （ND）, where we must transition from ＂accuracy＂ to ＂precision＂ eras. Finally, we can make connections with τ transitions and, perhaps, with dark matter. Charm dynamics acts as a bridge between the worlds of light- and heavy-flavor hadrons （namely, beauty hadrons）, and finding regional asymmetries in many-body final states may prove to be a ＂game changer＂. There are several different approaches to achieving these goals： for exam- ple, experiments such as the Super Tau-Charm Factory, Super Beauty Factory, and the Super Z~ Factory act as gatekeepers - and deeper thinking regarding symmetries.

关键词： CKM matrix HQE & OPE CPV in △C≠ 0 ≠ △B &τ decays

impact of Drain Effluent on Surficial Sediments in the Mediterranean Coastal Wetland: Sedimentological Characteristics and Metal Pollution Status at Lake Manzala, Egypt

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Journal of Ocean University of China 2019年第4期18卷 834-848页

作者： FARHAT Hassan i. Geology Department Faculty of Science Suez University

Surface sediments were collected from Lake Manzala, the Mediterranean coastal wetland located to the east of the Nile Delta, Egypt, to assess the effect of drain effluent on the spatial variations of sedimentary characteristics and heavy metal pollution. Grain-size compositions, textures, and heavy metal distribution patterns in sediments are presented using GiS technique. Results of the analysis of the sediment showed a clear effect of drain effluent, with an increase in fine fractions and homogeneous suspensions in transportation mode. Lake sediments were dominated by sandy mud textures, and mode of transportation was homogeneous sus- pension and rolling. Spatial distribution of heavy metals (Fe, Mn, Zn, Cu, Ni, Cr, and Pb) was studied in the lake’s surficial sediments, along with their relationship to drain effluent and their contamination status in the ecological system. Heavy metal pollution status was assessed by means of accepted sediment quality guidelines and contamination assessment methods (contamination factor, con- tamination degree, modified contamination degree, geo-accumulation, and enrichment factor). Among the determined heavy metals, Pb had the most ecological risk. Generally, the heavy metals in the surface sediments indicated pollution risk ranging from moderate to considerable, particularly, in those sites facing drains and inlets that had the highest toxic effluent. The results were interpreted by statistical means. A cluster analysis defined areas facing drain discharge and inlets as separated groups. ANOVA indicated that most of the sedimentation and studied metals directed this clustering.

关键词： Lake Manzala Mediterranean wetland metal pollution sedimentological characteristics

THE DRAG EXERTED BY AN OBLATE ROTATiNG ATMOSPHERE ON AN ARTiFiCiAL SATELLiTE

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Applied Mathematics and Mechanics(English Edition) 2002年第9期23卷 1016-1028页

作者： KH.i.Khalil National Research institute of Astronomy and Geophsics-Helwan Cairo Egypt

A theory is formulated for the motion of an artificial satellite under the joint effects of Earth oblateness and atmospheric drag. The Hamilton ' s equations of motion are derived including the zonal harmonics of the geopotential up to J4 and the drag accelerations. The atmospheric model is an oblate rotating model in which the atmospheric rotation lags behind that of the Earth as the increasing distance from the Earth. The drag free problem is first solved via two canonical transformations to eliminate in succession the short and long period terms. An operator D is then defined and used to formulate the drag acceleration in terms of the double primed variables expressing the solution of the drag-free problem.

关键词： oblateness the Hamiltonian Lie transform

Machines as readers: A solution to the copyright problem

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2005年第11期6卷 1179-1187页

作者： SHAMOS Michael i. School of Computer Science Carnegie Mellon University Pittsburgh PA 15213 USA Department of Computer Science University of Hong Kong Hong Kong China

Copyright and its international complications have presented a significant barrier to the Universal Digital Library （UDL）＇s mission to digitize all the published works of mankind and make them available throughout the world. We discuss the effect of existing copyright treaties and various proposals, such as compulsory licensing and the public lending fight that would allow access to copyrighted works without requiring permission of their owners. We argue that these schemes are ineffective for purposes of the UDL. instead, making use of the international consensus that copyright does not protect facts, information or processes, we propose to scan works digitally to extract their intellectual content, and then generate by machine synthetic works that capture this content, and then translate the generated works automatically into multiple languages and distribute them free of copyright restriction.

关键词： Universal Digital Library (UDL) Copyright Digital rights management Compulsory license Berne convention Public lending right Synthetic documents Machine translation

Modified Nonlinear Model of Arcsin-Electrodynamics

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Communications in Theoretical Physics 2016年第7期65卷 59-65页

作者： S.i.Kruglov Department of Chemical and Physical Sciences University of Toronto

A new modified model of nonlinear arcsin-electrodynamics with two parameters is proposed and *** obtain the corrections to the Coulomb law. The effect of vacuum birefringence takes place when the external constant magnetic field is present. We calculate indices of refraction for two perpendicular polarizations of electromagnetic waves and estimate bounds on the parameter γ from the BMV and PVLAS experiments. it is shown that the electric field of a point-like charge is finite at the origin. We calculate the finite static electric energy of point-like particles and demonstrate that the electron mass can have the pure electromagnetic nature. The symmetrical Belinfante energy-momentum tensor and dilatation current are found. We show that the dilatation symmetry and dual symmetry are broken in the model suggested. We have investigated the gauge covariant quantization of the nonlinear electrodynamics fields as well as the gauge fixing approach based on Dirac's brackets.

关键词： vacuum birefringence energy-momentum tensor static electric energy dilatation current dual symmetry quantization Dirac's brackets

Measurement of R at VEPP-2000

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Chinese Physics C 2010年第6期34卷 669-674页

作者： i.B.Logashenko Budker institute of Nuclear Physics Novosibirsk State University

The new e^＋e^- storage ring, VEPP-2000, is being commissioned at Budker institute of Nuclear Physics, Novosibirsk. Measurement of the total cross section e^＋e^- → hadrons in the whole VEPP-2000 energy range is one ... 详细信息

关键词： hadrons pion form factor cross section muon magnetic moment

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Communications in Theoretical Physics 2011年第10期56卷 745-750页

作者： i.F.Barna KFKi Atomic Energy Research institute of the Hungarian Academy of Sciences Thermohydraulics Department(KFKI-AEKI)H-1525 BudapestP.O.Box 49Hungary

in this article we will present pure three dimensional analytic solutions for the Navier-Stokes and the continuity equations in Cartesian coordinates. The key idea is the three-dimensional generalization of the well-known self-similar Ansatz of Barenblatt. A geometrical interpretation of the Ansatz is given also. The results are the Kummer functions or strongly related. Our final formula is compared with other results obtained from group theoretical approaches.

关键词： Navier-Stokes equation self-similar solution

Genotypic Profiling and Clinical impact of Helicobacter pylori Virulence Genes (GLM, HPU, VacA, CagA, and iceA) in Gastroduodenal Diseases among Libyan Patients

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American Journal of Molecular Biology 2025年第1期15卷 53-74页

作者： Aya M. Al-Farjany Madiha W. El-Awamie Nariman A. Elsharif Omar S. Alqabbasi Wail A. Alhawari Fatema i. E. Najem Tarek S. Bader Farag A. Bleiblo Department of Life Sciences/Microbiology Programme School of Basic Sciences Libyan Academy of Postgraduate Studies Benghazi Libya Department of Microbiology Faculty of Science University of Benghazi Benghazi Libya Department of Molecular Diagnosis Faculty of Biomedical Sciences University of Benghazi Benghazi Libya Libyan international Medical University Benghazi Libya Benghazi Center for infectious Diseases and immunology Benghazi Libya Navco Pharmaceuticals Limited Burlington Ontario Canada

Helicobacter pylori infection represents a widespread chronic condition with varying prevalence influenced by race, ethnicity, and geography. The severity of H. pylori-associated diseases is determined by an array of virulence factors. Although extensive studies have been conducted globally, data on the distribution of Helicobacter pylori virulence genes in Libya remain limited, constraining insights into the pathogenicity of local strains and hindering the development of targeted interventions. This study aimed to evaluate the prevalence of H. pylori infection, characterize essential virulence genes [vacA variants (s1/s2, m1/m2), cagA, and iceA1], and examine their association with gastroduodenal diseases among Libyan patients. Gastric biopsies from 144 participants were analyzed using polymerase chain reaction (PCR) assays, and risk factor data were collected via questionnaires. H. pylori was detected in 63.2% of samples by PCR. The vacA gene was present in 84.6% of cases, cagA in 58.2%, and iceA1 in 29.7%. Among vacA variants, s1 allele was most common (53.2%), followed by m1 (42.9%), m2 (37.7%), and s2 (13%) alleles. Significant associations were identified between specific virulence genes and the development of gastroduodenal diseases, highlighting their role in pathogenicity. This investigation is one of Libya’s first comprehensive assessments of H. pylori virulence factors, addressing a critical epidemiological gap. The high prevalence of virulence genes suggests their potential as disease biomarkers. These findings contribute to a deeper understanding of H. pylori pathogenicity within the Libyan population and establish a basis for future clinical interventions and public health strategies to manage and prevent H. pylori-associated diseases in Libya and comparable regions.

关键词： H. pylori Virulence Genes Gastroduodenal Diseases Gastric Biopsy PCR

Morphology,structure and magnetic behavior of orthorhombic and hexagonal HoFeO_(3)synthesized via solution combustion approach

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Journal of Rare Earths 2022年第2期40卷 296-301,I0004页

作者： K.D.Martinson i.S.Kondrashkova M.i.Chebanenko A.S.Kiselev T.Yu Kiseleva V.i.Popkov ioffe institute 26 PoliteknicheskayaSL Petersburg194021Russia Saint Petersburg State institute of Technology 26 MoskovskySt.Petersburg190013Russia Faculty of Physics M.V.Lomonosov State UniversityLeninskie CoryMoscow119991Russia

Nanostructured HoFeO_(3)powders were obtained by solution combustion method at various glycinenitrate ratios(G/N=0.2,0.4,...,1.4).According to X-ray powder diffractometry data,the presence of two modifications of HoFeO_(3)in the synthesized samples was established:orthorhombic(Pbnm)and hexagonal(P63/mmc).The crystallite size of the obtained compositions varies from 62±6 to 29±3 nm,depending on the G/N *** magnetic structure studies,it is found that HoFeO_(3)obtained with a stoichiometric amount of glycine in the reaction solution is in the magnetically ordered state and is represented by a sextet with quadrupole splitting(QS)=0 mm/s,isomeric shift(iS)=0.36 mm/s and effective field strength(Heff)=497 *** to the results of vibrational magnetometry,it is found that the orthoferrites obtained have a ferromagnetic structure,the main parameters of which(Ms,Mr and Hc)systematically change with a change in the redox ratio of the reaction mixture and,as a consequence,their phase composition,and reach maximum values at a G/N ratio=*** the samples obtained with a significant excess and lack of glycine(G/N=0.2 and 1.4),despite their amorphous nature,hysteresis loops characteristic of the ferromagnetic state of the substance is *** is hopeful to obtain a pure hexagonal modification of HoFeO_(3)via heat treatment on amorphous products of glycine-nitrate combustion.

关键词： Crystal structure Rare earth compounds Perovskites Nanomaterials Magnetic materials

Kinemaitcs in spatially flat FLRW spacetimes

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Chinese Physics C 2021年第10期45卷 92-101页

作者： ion i.Cotäescu West University of Timiäoara

The kinematics on spatially flat FLRW spacetimes is presented for the first time in local charts with physical coordinates,i.e.,the cosmic time and proper Cartesian space coordinates of Painlevé-*** is shown that there exists a conserved momentum that determines the form of the covariant four-momentum on geodesics in terms of physical ***,with the help of this conserved momentum,the peculiar momentum can be defined,thus separating the peculiar and recessional motions without *** is shown that the energy and peculiar momentum satisfy the mass-shell condition of special relativity while the recessional momentum does not produce *** this framework,the measurements of the kinetic quantities along geodesics performed by different observers are analyzed,pointing out an energy loss of the massive particles similar to that producing the photon *** examples of the kinematics on the de Sitter expanding universe and a new Milne-type spacetime are extensively analyzed.

关键词： FLRW specetime peculiar momentum recessional momentum conserved quantities energy loss redshift de Sitter expanding universe Milne-type universe