Physical degrees of freedom in stabilized brane world models

We consider brane world models with interbrane separation stabilized by the Goldberger-Wise scalar field. For arbitrary background, or vacuum configurations of the gravitational and scalar fields in such models, we construct the second variation Lagrangian, study its gauge invariance, find the corresponding equations of motion and decouple them in a suitable gauge. We also derive an effective four-dimensional Lagrangian for such models, which describes the massless graviton, a tower of massive gravitons and a tower of massive scalars. It is shown that for a special choice of the background solution the masses of the graviton excitations may be of the order of a few TeV, the radion mass of the order of 100 GeV, the inverse size of the extra dimension being tens of GeV. In this case the coupling of the radion to matter on the negative tension brane is approximately the same as in the unstabilized model with the same values of the fundamental five-dimensional energy scale and the interbrane distance.Comment: 17 pages, LaTeX, corrected typos, amended the normalization constants of the scalar modes and their coupling constants to matte

Magnetometric Studies of Catalyst Refuses in Nanocarbon Materials

It is shown that magnetometry can be employed as an effective tool to control the content of a ferromagnetic constituent in nanocarbon materials. We propose a thermochemical treatment protocol to achieve extensive cleaning of the source nanocarbon materials from ferromagnetic refuses

Protease Activated Receptor Signaling Is Required for African Trypanosome Traversal of Human Brain Microvascular Endothelial Cells

Human African trypanosomiasis, or sleeping sickness, occurs when single-cell trypanosome protozoan parasites spread from the blood to brain over the blood-brain barrier (BBB). This barrier is composed of brain microvascular endothelial cells (BMECs) especially designed to keep pathogens out. Safe drugs for treating sleeping sickness are lacking and alternative treatments are urgently required. Using our human BMEC BBB model, we previously found that a parasite protease, brucipain, induced calcium activation signals that allowed this barrier to open up to parasite crossing. Because human BMECs express protease-activated receptors (PARs) that trigger calcium signals in BMECs, we hypothesized a functional link between parasite brucipain and BMEC PARs. Utilizing RNA interference to block the production of one type of PAR called PAR-2, we hindered the ability of trypanosomes to both open up and cross human BMECs. Using gene-profiling methods to interrogate candidate BMEC pathways specifically triggered by brucipain, several pathways that potentially link brain inflammatory processes were identified, a finding congruent with the known role of PAR-2 as a mediator of inflammation. Overall, our data support a role for brucipain and BMEC PARs in trypanosome BBB transmigration, and as potential triggers for brain inflammation associated with the disease

Design, Performance and Calibration of the CMS Forward Calorimeter Wedges

We report on the test beam results and calibration methods using charged particles of the CMS Forward Calorimeter (HF). The HF calorimeter covers a large pseudorapidity region (3\l |\eta| \le 5), and is essential for large number of physics channels with missing transverse energy. It is also expected to play a prominent role in the measurement of forward tagging jets in weak boson fusion channels. The HF calorimeter is based on steel absorber with embedded fused-silica-core optical fibers where Cherenkov radiation forms the basis of signal generation. Thus, the detector is essentially sensitive only to the electromagnetic shower core and is highly non-compensating (e/h \approx 5). This feature is also manifest in narrow and relatively short showers compared to similar calorimeters based on ionization. The choice of fused-silica optical fibers as active material is dictated by its exceptional radiation hardness. The electromagnetic energy resolution is dominated by photoelectron statistics and can be expressed in the customary form as a/\sqrt{E} + b. The stochastic term a is 198% and the constant term b is 9%. The hadronic energy resolution is largely determined by the fluctuations in the neutral pion production in showers, and when it is expressed as in the electromagnetic case, a = 280% and b = 11%

Design, Performance, and Calibration of CMS Hadron Endcap Calorimeters

Detailed measurements have been made with the CMS hadron calorimeter endcaps (HE) in response to beams of muons, electrons, and pions. Readout of HE with custom electronics and hybrid photodiodes (HPDs) shows no change of performance compared to readout with commercial electronics and photomultipliers. When combined with lead-tungstenate crystals, an energy resolution of 8\% is achieved with 300 GeV/c pions. A laser calibration system is used to set the timing and monitor operation of the complete electronics chain. Data taken with radioactive sources in comparison with test beam pions provides an absolute initial calibration of HE to approximately 4\% to 5\%

WS 2003/2004

This work is aimed to give an overview in the field of Web services technology (WSDL, UDDI, SOAP) in correlation with QoS aspects. A review of standards and approaches used in Web Services composition is presented. In particular, it outlines the methods of declarative composition in dynamic and Peer-To-Peer environment using statecharts as well as advantages of semantic composition using DAML-S markup language and approaches of invoking Web Services using Mobile Agents. The global planning approach used to optimally select component services during execution of a composite service is described. The approach is explicitly based on Quality-of-Service (QoS) characteristics of services and extends the standard basis of Web services technologies. Table of Conten

On aggregation of isomorphous nitrogen impurity in synthetic diamonds (system Fe-Ni-C)

Актуальность исследования определяется значимостью азота как основной структурной примеси в алмазе, содержание и форма которой оказывают влияние на свойства алмаза, его цветовые характеристики и используются при анализе температурно-временных условия природного алмазообразования. Цель: исследование особенностей агрегирования азота в синтетических алмазах, выращенных в системе Fe-Ni-C. Объект и методы. Изученный образец синтетического монокристалла алмаза получен методом температурного градиента при высоких Р, Т-параметрах в поле стабильности на многопуансонном аппарате высокого давления типа «разрезная сфера». Определение азота и степени его агрегации проводили с помощью ИК-Фурье спектрометра Bruker Vertex-70 с микроскопом Hyperion 2000. При анализе спектральных данных использовалась специализированная программа обработки ИК-спектров алмаза IR'nDi-Module. Результаты и выводы. Проведено изучение характера образования парных ассоциатов изоморфной примеси азота (степени агрегирования) в октаэдрических секторах роста синтетического алмаза, полученного в металл-углеродной системе c высоким содержанием никеля (металл-растворитель Fe20Ni80 ат. %). После постепенного достижения полной агрегации азота со стороны внешних областей кристалла зафиксирована прогрессирующая обратная деагрегация азота в его внутренних, ранее образованных, зонах. Установленный факт не может быть объяснен в рамках известной однонаправленной кинетики процесса агрегирования азота и указывает на наличие дополнительного фактора, влияющего на данную реакцию в алмазах с повышенным содержанием сопутствующей примеси никеля. Впервые высказано предположение о возможности деагрегации азота, инициированной перераспределением азота из азотных ассоциатов (А-дефектов) в никель-азотные комплексы (NE-центры).The relevance of the research is determined by the importance of nitrogen as the main structural impurity in diamond, the content and form of which affect the properties of diamond, its color characteristics and are used in the analysis of the temperature-time conditions of natural diamond formation. The purpose of this work is to study the features of nitrogen impurity aggregation in synthetic diamonds grown in the Fe-Ni-C system. Object and methods. The studied sample of a synthetic single crystal of diamond was obtained in Fe-Ni-C system by the temperature gradient method at high P, T parameters in the field of stability on a multi-anvil high-pressure apparatus of the «split sphere» type. Determination of nitrogen and the degree of its aggregation were performed using a Bruker Vertex-70 IR Fourier spectrometer with a Hyperion 2000 microscope. When analyzing the spectral data, a specialized program for processing the IR spectra of diamond IR'nDi-Module was used. Results and conclusions. The authors have studied the variation in formation of pair associates of isomorphic nitrogen impurity (degree of aggregation) in the octahedral growth sectors of synthetic diamond obtained with a high nickel content in metal-solvent (Fe20Ni80 at. %). After the gradual achievement of complete aggregation of nitrogen in the outer regions of the crystal, a progressive reverse deaggregation of nitrogen was recorded in its internal, previously formed zones. The established fact cannot be explained within the framework of the known unidirectional kinetics of the nitrogen aggregation and indicates the presence of an additional factor affecting this reaction in diamonds with a high content of an accompanying impurity of nickel. The possibility of nitrogen deaggregation initiated by the redistribution of nitrogen from nitrogen associates (A-defects) to nickel-nitrogen complexes (NE-centers) was suggested for the first time

Growth Story of One Diamond: A Window to the Lithospheric Mantle

A diamond plate cut out of a transparent, colorless octahedral diamond crystal of gem quality, with a small chromite inclusion in the core, sampled from the XXIII CPSU Congress kimberlite (Yakutia, Mirny kimberlite field, vicinities of Mirny city), has been studied by several combined methods: absorption spectroscopy at different wavelengths (UV-visible, near- and mid-IR); photoluminescence, cathodoluminescence, and Raman spectroscopy (local version) and lattice strain mapping; birefringence in cross-polarized light; and etching. The diamond plate demonstrates a complex growth history consisting of four stages: nucleation and growth to an octahedron → habit change to a cuboid → habit change to octahedron-1 → habit change to octahedron-2. The growth history of the diamond records changes in the crystallization conditions at each stage. The revealed heterogeneity of the crystal structure is associated with the distribution and speciation of nitrogen defects. The results of this study have implications for the information value of different techniques as to the diamond structure defects, as well as for the as yet poorly known evolution of the subcontinental lithospheric mantle in the Siberian craton, recorded in the multistage growth of the diamond crystal. At the time of writing, reconstructing the conditions for each stage is difficult. Meanwhile, finding ways for such reconstruction is indispensable for a better understanding of diamond genesis, and details of the lithosphere history