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arXiv
Subject Source arXiv URL https://arxiv.org/abs/astro-ph/0601012view Article Title Neutrino Telescopy in the Mediterranean SeaAuthors Ulrich F. KatzAbstract The observation of high-energy extraterrestrial neutrinos is one of the most promising future options to increase our knowledge on non-thermal processes in the universe. Neutrinos are e.g. unavoidably produced in environments where high-energy hadrons collide; in particular this almost certainly must be true in the astrophysical accelerators of cosmic rays, which thus could be identified unambiguously by sky observations in "neutrino light". On the one hand, neutrinos are ideal messengers for astrophysical observations since they are not deflected by electromagnetic fields and interact so weakly that they are able to escape even from very dense production regions and traverse large distances in the universe without attenuation. On the other hand, their weak interaction poses a significant problem for detecting neutrinos. Huge target masses up to gigatons must be employed, requiring to instrument natural abundances of media such as sea water or antarctic ice. The first generation of such neutrino telescopes is taking data or will do so in the near future, while the second-generation projects with cubic-kilometre size is under construction or being prepared. This report focuses on status and prospects of current (ANTARES, NEMO, NESTOR) and future (KM3NeT) neutrino telescope projects in the Mediterranean Sea.Is Part Of Prog.Part.Nucl.Phys. 57 (2006) 273-282 2005-12-31 Identifier ISSN: DOI 10.1016/j.ppnp.2006.01.006Category astro-phLicense -
arXiv
Subject Source arXiv URL https://arxiv.org/abs/physics/0512275view Article Title Silicon detectors for the next generation of high energy physics experiments: expected degradationAuthors I. Lazanu; S. LazanuAbstract There exists an enormous interest for the study of very high energy domain in particle physics, both theoretically and experimentally, in the aim to construct a general theory of the fundamental constituents of matter and of their interactions. Until now, semiconductor detectors have widely been used in modern high energy physics experiments. They are elements of the high resolution vertex and tracking system, as well as of calorimeters. The main motivation of this work is to discuss how to prepare some possible detectors - only silicon option being considered, for the new era of HEP challenges because the bulk displacement damage in the detector, consequence of irradiation, produces effects at the device level that limit their long time utilisation, increasing the leakage current and the depletion voltage, eventually up to breakdown, and thus affecting the lifetime of detector systems. In this paper, physical phenomena that conduce to the degradation of the detector are discussed and effects are analysed at the device level (leakage current and effective carrier concentration) in the radiation environments expected in the next generation of hadron colliders after LHC, at the next lepton and gamma-gamma colliders, as well as in astroparticle experiments, in conditions of long time continuum irradiations, for different technological options. The predicted results permit a better decision to obtain devices with harder parameters to radiation.Is Part Of 2005-12-31 Identifier ISSN: Category physics.ins-det hep-phLicense -
PMC OpenAccess
Subject 화학 Source PMC OpenAccess URL https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6147703/view Article Title Synthesis of Novel, Potentially Biologically Active Dibenzosuberone DerivativesAuthors Sonja Merkaš; Mladen Litvić; Ivica Cepanec; Vladimir VinkovićAbstract Novel representatives of the important group of biologically active dibenzosuberone derivatives were prepared: 3,7-dibromo-5-(dimethylaminoethyl-oxyimino)-10,11-dihydro-5H-dibenzo[a,d]cyclohepta-1,4-diene (1), 3,7-dibromo-5-(3-dimethylaminopropylidene)-10,11-dihydro-5H-dibenzo[a,d]cycloheptene (2) and 1,7-dibromo-5-(3-dimethylaminopropylidene)-10,11-dihydro-5H-dibenzo-[a,d]-cycloheptene (3). These compounds are potential tricyclic antidepressants (TCAs), which are still the most frequently prescribed antidepressants in many countries.Is Part Of Molecules : A Journal of Synthetic Chemistry and Natural Product Chemistry 2005-12-31 , Vol.10 (12) , 1429-1437 Identifier ISSN: 1420-3049 DOI 10.3390/10121429Publisher MDPICategory Dibenzosuberone; tricyclic antidepressants; bromination; amitriptiline; noxiptilineLicense Reproduction is permitted for noncommercial purposes. -
arXiv
Subject 수학 Source arXiv URL https://arxiv.org/abs/math/0601012view Article Title Frobenius-Schur Indicators and Exponents of Spherical CategoriesAuthors Siu-Hung Ng; Peter SchauenburgAbstract We obtain two formulae for the higher Frobenius-Schur indicators: one for a spherical fusion category in terms of the twist of its center and the other one for a modular tensor category in terms of its twist. The first one is a categorical generalization of an analogous result by Kashina, Sommerhauser, and Zhu for Hopf algebras, and the second one extends Bantay's 2nd indicator formula for a conformal field theory to higher degree. These formulae imply the sequence of higher indicators of an object in these categories is periodic. We define the notion of Frobenius-Schur (FS-)exponent of a pivotal category to be the global period of all these sequences of higher indicators, and we prove that the FS-exponent of a spherical fusion category is equal to the order of the twist of its center. Consequently, the FS-exponent of a spherical fusion category is a multiple of its exponent, in the sense of Etingof, by a factor not greater than 2. As applications of these results, we prove that the exponent and the dimension of a semisimple quasi-Hopf algebra H have the same prime divisors, which answers two questions of Etingof and Gelaki affirmatively for quasi-Hopf algebras. Moreover, we prove that the FS-exponent of H divides dim(H)^4. In addition, if H is a group-theoretic quasi-Hopf algebra, the FS-exponent of H divides dim(H)^2, and this upper bound is shown to be tight.Is Part Of Adv. Math. 211 (2007) no. 1, 34--71 2005-12-31 Identifier ISSN: DOI 10.1016/j.aim.2006.07.017Category math.QA math.CTLicense -
arXiv
Subject Source arXiv URL https://arxiv.org/abs/hep-ex/0512077view Article Title The CMS High Level TriggerAuthors The CMS Trigger; Data Acquisition GroupAbstract At the Large Hadron Collider at CERN the proton bunches cross at a rate of 40MHz. At the Compact Muon Solenoid experiment the original collision rate is reduced by a factor of O (1000) using a Level-1 hardware trigger. A subsequent factor of O(1000) data reduction is obtained by a software-implemented High Level Trigger (HLT) selection that is executed on a multi-processor farm. In this review we present in detail prototype CMS HLT physics selection algorithms, expected trigger rates and trigger performance in terms of both physics efficiency and timing.Is Part Of Eur.Phys.J.C46:605-667,2006 2005-12-31 Identifier ISSN: DOI 10.1140/epjc/s2006-02495-8Category hep-exLicense -
arXiv
Subject Source arXiv URL https://arxiv.org/abs/quant-ph/0601005view Article Title The Localization of $s$-Wave and Quantum Effective Potential of a Quasi-Free Particle with Position-Dependent MassAuthors Guo-Xing JU; Yang Xiang; Zhong-Zhou RenAbstract The properties of the s-wave for a quasi-free particle with position-dependent mass(PDM) have been discussed in details. Differed from the system with constant mass in which the localization of the s-wave for the free quantum particle around the origin only occurs in two dimensions, the quasi-free particle with PDM can experience attractive forces in $D$ dimensions except D=1 when its mass function satisfies some conditions. The effective mass of a particle varying with its position can induce effective interaction which may be attractive in some cases. The analytical expressions of the eigenfunctions and the corresponding probability densities for the s-waves of the two- and three-dimensional systems with a special PDM are given, and the existences of localization around the origin for these systems are shown.Is Part Of 2005-12-31 Identifier ISSN: DOI 10.1088/0253-6102/46/5/010Category quant-phLicense -
arXiv
Subject 수학 Source arXiv URL https://arxiv.org/abs/gr-qc/0601002view Article Title On the differential geometry of curves in Minkowski spaceAuthors J. B. Formiga; C. RomeroAbstract We discuss some aspects of the differential geometry of curves in Minkowski space. We establish the Serret-Frenet equations in Minkowski space and use them to give a very simple proof of the fundamental theorem of curves in Minkowski space. We also state and prove two other theorems which represent Minkowskian versions of a very known theorem of the differential geometry of curves in tridimensional Euclidean space. We discuss the general solution for torsionless paths in Minkowki space. We then apply the four-dimensional Serret-Frenet equations to describe the motion of a charged test particle in a constant and uniform electromagnetic field and show how the curvature and the torsions of the four-dimensional path of the particle contain information on the electromagnetic field acting on the particle.Is Part Of 2005-12-31 Identifier ISSN: DOI 10.1119/1.2232644Category gr-qc math.DGLicense -
arXiv
Subject 수학 Source arXiv URL https://arxiv.org/abs/math/0601015view Article Title Elliptic Curves as Attractors in ${\mathbb P}^2$ Part 1: DynamicsAuthors Araceli Bonifant; Marius Dabija; John MilnorAbstract A study of rational maps of the real or complex projective plane of degree two or more, concentrating on those which map an elliptic curve onto itself, necessarily by an expanding map. We describe relatively simple examples with a rich variety of exotic dynamical behaviors which are perhaps familiar to the applied dynamics community but not to specialists in several complex variables. For example, we describe smooth attractors with riddled or intermingled attracting basins, and we observe ``blowout'' bifurcations when the transverse Lyapunov exponent for the invariant curve changes sign. In the complex case, the elliptic curve (a topological torus) can never have a trapping neighborhood, yet it can have an attracting basin of large measure (perhaps even of full measure). We also describe examples where there appear to be Herman rings (that is topological cylinders mapped to themselves with irrational rotation number) with open attracting basin. In some cases we provide proofs, but in other cases the discussion is empirical, based on numerical computation.Is Part Of 2005-12-31 Identifier ISSN: Category math.DS math.CVLicense -
Springer Nature
Subject Source Springer Nature URL http://dx.doi.org/10.1186/1751-0147-46-229view Article Title Blood Selenium Associated with Health and Fertility in Norwegian Dairy HerdsAuthors Kommisrud, E; Østerås, O; Vatn, TAbstract {p=A survey of blood selenium (Se) concentrations in Norwegian Red heifers and dry period cows was conducted to reveal possible association to management, feeding, health and fertility. Selenium contents were determined in 254 herd blood samples consisting of pooled samples from individual non-lactating animals from herds in 5 counties. The Se concentrations showed a normal distribution with mean 0.09 μg Se/g blood, with a standard deviation (SD) of 0.05, and ranged from 0.02 to 0.23 μg/g, with 50 % of the samples being between 0.06 and 0.11 μg/g. The herds with Se concentrations below 0.06 μg/g were smaller (21.4 ± 8.7 cow-years) than those with Se levels above 0.11 μg/g (27.5 ± 14.1 cow-years) ( P < 0.01), but there were no differences in milk yield, incidence of replacement, proportion of animal culling, amount of concentrate or grass silage as percentage of energy consumption between the groups. Treatment registration records showed a tendency that more animals in the low Se herds were treated for all the diseases included in this investigation (64.8 animals per 100 cow-years) than those in the high Se herds (57.5 per 100 cow-years), while no such differences were revealed for individual disorders. There was, however, a significant difference in bulk milk somatic cell counts (BMSCC) between low and high Se herds, their values being 137 000 and 155 000 cells/ml, respectively. This difference was significantly influenced by herd size. Furthermore, a total of 4 916 lactations were analyzed from individual health and fertility recordings, including 2 934 first lactations and 1 982 later lactations. The present study revealed a reduced incidence of disease treatment with increased Se concentrations from 0.02 to 0.23 μg Se/g blood. In this regard, there seemed to be an optimum of 0.10 to 0.15 μg Se/g for all types of mastitis treatments summarized, and for treatment of retained placenta. Thus, herd Se concentrations below and above these values was connected with increased probability for sum mastitis and retained placenta, reflecting the effect of the quadratic term of Se. The cow (composite) milk somatic cell count (SCC) was lower in lactations from low Se herds than in high Se herds with a marked SCC increase in the Se concentration interval from 0.11–0.13 μg/g blood. In conclusion, heifers and dry period cows in Norway are low in blood Se content and there seems to be a positive association between increased blood Se concentration pre partum and decreased incidence of mastitis, ovarian cysts and anoestrus/silent oestrus post partum ., h1=Abstract}Is Part Of Acta Veterinaria Scandinavica 2005-12-31 , Vol.46 (4) , 1 Identifier EISSN: null ; PISSN: DOI 10.1186/1751-0147-46-229Publisher BioMed CentralLicense ©2002 The Author(s) -
PMC OpenAccess
Subject 화학 Source PMC OpenAccess URL https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6147633/view Article Title Cyclization of Free Radicals at the C-7 Position of Ethyl Indole–2-carboxylate Derivatives: an Entry to a New Class of Duocarmycin AnaloguesAuthors Naim H. Al-Said; Khaled Q. Shawakfeh; Wasim N. AbdullahAbstract Aryl free-radicals generated at the C-7 position of ethyl indole-2-carboxylates bearing N-allyl and propargylic groups triggered intramolecular cyclizations to furnish a new class of Duocarmycin analogues, formal ethyl pyrrolo[3,2,1-ij]quinoline-2-carboxylate derivatives, through the less favorable 6-endo-trig cyclization mode.Is Part Of Molecules : A Journal of Synthetic Chemistry and Natural Product Chemistry 2005-12-31 , Vol.10 (12) , 1446-1457 Identifier ISSN: 1420-3049 DOI 10.3390/10121446Publisher MDPICategory Duocarmycin; free-radicals; intramolecular cyclization; indole; pyrroloquinolineLicense Reproduction is permitted for noncommercial purposes.