Supersonic dusty-gas flows with Knudsen effect in interphase momentum exchange

On the basis of the two-continuum model of dilute gas-solid suspensions, the dynamic behavior of inertial particles in supersonic dusty-gas flows past a blunt body is studied for moderate Reynolds numbers, when the Knudsen effect in the interphase momentum exchange is significant. The limits of the inertial particle deposition regime in the space of governing parameters are found numerically under the assumption of the slip and free-molecule flow regimes around particles. As a model problem, the flow structure is obtained for a supersonic dusty-gas point-source flow colliding with a hypersonic flow of pure gas. The calculations performed using the full Lagrangian approach for the near-symmetry-axis region and the free-molecular flow regime around the particles reveal a multi-layer structure of the dispersed-phase density with a sharp accumulation of the particles in some thin regions between the bow and termination shock waves.

El aborto en la ley europea : derechos humanos, derechos sociales y la nueva tendencia cultural

Resumen: Este artículo se propone analizar: 1) si existe un verdadero “derecho al aborto” en la Convención Europea de Derechos Humanos, 2) si el aborto es una violación a los Derechos Sociales, 3) si la reciente tendencia en Europa frente a la restricción del aborto muestra que éste es un problema social y no un derecho o una libertad individual. Legisladores y organizaciones esperando proteger mejor a los niños y a las mujeres, del aborto, encontrarán críticas a la idea de la existencia de un derecho humano al aborto, así como el marco legal en el cual elaborar leyes protectorias.

Inhomogeneous isoparametric elements for stress analysis of composites

The concept of inhomogeneous element is proposed and the formulations of the inhomogeneous isoparametric elements for stress analysis of four kinds of problems are derived. As an example of applications of the inhomogeneous elements, the stress distribution in a cone-like composite syntheticrope termination is calculated.

Internationales Otolithen-Symposium in Australien

The Third International Symposium on Fish Otolith Research and Application in Townsville, Australia, from 11 to 16 July 2004, gathered around 300 scientists from 30 nations (http://www.otolith2004.com). Mayor topics were: structure of otoliths and function; micro-Chemitry and composition; determination of age and growth and their validation; de-termination of age in fish from tropical habitats; influence of climate, ecology and population biology; statistik and modelling; stock assessment and fishery management; quality control in institutions carrying out age determinations, and data processing; and development of technologies. The symposium was preceeded by a workshop at the James Cook University, Townsville, to enhance the knowledge and skill of participants in theoretrical and practical aspects for prearation of otoliths and interpretation of annuli; difficulties in interpreting age in tropical fish; daily increments as well as shape and image analysis.

Measurement of the band bending and surface dipole at chemically functionalized Si(111)/vacuum interfaces

The core-level energy shifts observed using X-ray photoelectron spectroscopy (XPS) have been used to determine the band bending at Si(111) surfaces terminated with Si-Br, Si-H, and Si-CH₃ groups, respectively. The surface termination influenced the band bending, with the Si 2p_3/2 binding energy affected more by the surface chemistry than by the dopant type. The highest binding energies were measured on Si(111)-Br (whose Fermi level was positioned near the conduction band at the surface), followed by Si(111)-H, followed by Si(111)-CH₃ (whose Fermi level was positioned near mid-gap at the surface). Si(111)-CH₃ surfaces exposed to Br₂(g) yielded the lowest binding energies, with the Fermi level positioned between mid-gap and the valence band. The Fermi level position of Br₂(g)-exposed Si(111)-CH₃ was consistent with the presence of negatively charged bromine-containing ions on such surfaces. The binding energies of all of the species detected on the surface (C, O, Br) shifted with the band bending, illustrating the importance of isolating the effects of band bending when measuring chemical shifts on semiconductor surfaces. The influence of band bending was confirmed by surface photovoltage (SPV) measurements, which showed that the core levels shifted toward their flat-band values upon illumination. Where applicable, the contribution from the X-ray source to the SPV was isolated and quantified. Work functions were measured by ultraviolet photoelectron spectroscopy (UPS), allowing for calculation of the sign and magnitude of the surface dipole in such systems. The values of the surface dipoles were in good agreement with previous measurements as well as with electronegativity considerations. The binding energies of the adventitious carbon signals were affected by band bending as well as by the surface dipole. A model of band bending in which charged surface states are located exterior to the surface dipole is consistent with the XPS and UPS behavior of the chemically functionalized Si(111) surfaces investigated herein.

Functional genomic studies of the structure and regulation of eukaryotic transcriptomes

The main focus of this thesis is the use of high-throughput sequencing technologies in functional genomics (in particular in the form of ChIP-seq, chromatin immunoprecipitation coupled with sequencing, and RNA-seq) and the study of the structure and regulation of transcriptomes. Some parts of it are of a more methodological nature while others describe the application of these functional genomic tools to address various biological problems. A significant part of the research presented here was conducted as part of the ENCODE (ENCyclopedia Of DNA Elements) Project.

The first part of the thesis focuses on the structure and diversity of the human transcriptome. Chapter 1 contains an analysis of the diversity of the human polyadenylated transcriptome based on RNA-seq data generated for the ENCODE Project. Chapter 2 presents a simulation-based examination of the performance of some of the most popular computational tools used to assemble and quantify transcriptomes. Chapter 3 includes a study of variation in gene expression, alternative splicing and allelic expression bias on the single-cell level and on a genome-wide scale in human lymphoblastoid cells; it also brings forward a number of critical to the practice of single-cell RNA-seq measurements methodological considerations.

The second part presents several studies applying functional genomic tools to the study of the regulatory biology of organellar genomes, primarily in mammals but also in plants. Chapter 5 contains an analysis of the occupancy of the human mitochondrial genome by TFAM, an important structural and regulatory protein in mitochondria, using ChIP-seq. In Chapter 6, the mitochondrial DNA occupancy of the TFB2M transcriptional regulator, the MTERF termination factor, and the mitochondrial RNA and DNA polymerases is characterized. Chapter 7 consists of an investigation into the curious phenomenon of the physical association of nuclear transcription factors with mitochondrial DNA, based on the diverse collections of transcription factor ChIP-seq datasets generated by the ENCODE, mouseENCODE and modENCODE consortia. In Chapter 8 this line of research is further extended to existing publicly available ChIP-seq datasets in plants and their mitochondrial and plastid genomes.

The third part is dedicated to the analytical and experimental practice of ChIP-seq. As part of the ENCODE Project, a set of metrics for assessing the quality of ChIP-seq experiments was developed, and the results of this activity are presented in Chapter 9. These metrics were later used to carry out a global analysis of ChIP-seq quality in the published literature (Chapter 10). In Chapter 11, the development and initial application of an automated robotic ChIP-seq (in which these metrics also played a major role) is presented.

The fourth part presents the results of some additional projects the author has been involved in, including the study of the role of the Piwi protein in the transcriptional regulation of transposon expression in Drosophila (Chapter 12), and the use of single-cell RNA-seq to characterize the heterogeneity of gene expression during cellular reprogramming (Chapter 13).

The last part of the thesis provides a review of the results of the ENCODE Project and the interpretation of the complexity of the biochemical activity exhibited by mammalian genomes that they have revealed (Chapters 15 and 16), an overview of the expected in the near future technical developments and their impact on the field of functional genomics (Chapter 14), and a discussion of some so far insufficiently explored research areas, the future study of which will, in the opinion of the author, provide deep insights into many fundamental but not yet completely answered questions about the transcriptional biology of eukaryotes and its regulation.

Autonomia da vontade, consensualismo e arbitragem: A extensão da cláusula compromissória a partes não-signatárias fundamentada na teoria dos grupos de sociedades. A prática da Corte Internacional de Arbitragem da Câmara de Comércio Internacional (CCI) e sua compatibilidade com o ordenamento jurídico brasileiro

A prática da arbitragem comercial internacional tem se deparado, há pelos menos quatro décadas, com a problemática da extensão da cláusula compromissória a uma parte não-signatária, integrante do mesmo grupo de sociedades a que pertence uma das partes integrantes da convenção, em razão do comportamento adotado pela parte não-signatária nas fases de negociação do contrato, execução ou extinção. Nesse sentido, a prática da Corte Internacional de Arbitragem da Câmara de Comércio Internacional dos últimos trinta anos e reiteradas decisões judiciais em países de diferentes tradições jurídicas como a França, Suíça e Estados Unidos têm se manifestado favoravelmente a essa extensão subjetiva da convenção de arbitragem. O estudo da doutrina nacional e da jurisprudência do Superior Tribunal de Justiça sobre os grupos de sociedades e seus efeitos, e a análise detida de diversos precedentes do Superior Tribunal de Justiça e do Supremo Tribunal Federal sobre a homologação de sentenças arbitrais estrangeiras, revelam a compatibilidade da referida prática arbitral internacional com o ordenamento jurídico brasileiro.

Para uma teoria do direito internacional do consumidor: a proteção do consumidor no livre comércio internacional

O consumidor é o agente vulnerável na relação de consumo internacional. O processo de globalização se apresenta, para o consumidor, como uma globalização do consumo. A globalização do consumo se caracteriza pelo comércio e fornecimento internacional de produtos e serviços por empresários/fornecedores transnacionais/globais, utilizando marcas de renome mundial, acessíveis a todos os consumidores do planeta, e agrava a vulnerabilidade do consumidor no mercado. A proteção jurídica do consumidor internacional é uma necessidade que os sistemas jurídicos nacionais não se mostram aptos a prover adequadamente, assim como o Direito Internacional também não. A presente tese demonstra a deficiência da Ciência do Direito na proteção do consumidor no contexto da globalização; demonstra como o próprio comércio internacional é prejudicado ao não priorizar de maneira absoluta e efetiva a proteção do consumidor na OMC, bem como ao mostrar-se apático diante dos diferentes níveis de proteção proporcionada aos consumidores em cada diferente sistema jurídico nacional; demonstra, também, como a proteção do consumidor de maneira uniforme e global por um direito comum aos Estados é possível e será capaz de tornar mais eficiente economicamente o processo de globalização do consumo, ao encorajar a participação mais intensa do consumidor no mercado internacional; e propõe a construção de um novo ramo do Direito dedicado ao problema, o Direito Internacional do Consumidor (DIC), por meio da elaboração de uma Teoria do Direito Internacional do Consumidor. O Direito Internacional do Consumidor pretende ser um direito comum e universal de proteção ao consumidor, fundado em métodos, conceitos, institutos, normas e princípios jurídicos universais. O DIC dialogará com outros ramos do Direito Público e Privado, especialmente o Direito Internacional Econômico, o Direito Internacional do Comércio, o Direito Internacional Privado, o Direito Processual Civil Internacional, e o Direito do Consumidor. Pretende-se com isto atender ao ideal de promover o livre comércio internacional com respeito aos Direitos Humanos.

Design of antenna-coupled lumped-element titanium nitride KIDs for long-wavelength multi-band continuum imaging

Many applications in cosmology and astrophysics at millimeter wavelengths including CMB polarization, studies of galaxy clusters using the Sunyaev-Zeldovich effect (SZE), and studies of star formation at high redshift and in our local universe and our galaxy, require large-format arrays of millimeter-wave detectors. Feedhorn and phased-array antenna architectures for receiving mm-wave light present numerous advantages for control of systematics, for simultaneous coverage of both polarizations and/or multiple spectral bands, and for preserving the coherent nature of the incoming light. This enables the application of many traditional "RF" structures such as hybrids, switches, and lumped-element or microstrip band-defining filters.

Simultaneously, kinetic inductance detectors (KIDs) using high-resistivity materials like titanium nitride are an attractive sensor option for large-format arrays because they are highly multiplexable and because they can have sensitivities reaching the condition of background-limited detection. A KID is a LC resonator. Its inductance includes the geometric inductance and kinetic inductance of the inductor in the superconducting phase. A photon absorbed by the superconductor breaks a Cooper pair into normal-state electrons and perturbs its kinetic inductance, rendering it a detector of light. The responsivity of KID is given by the fractional frequency shift of the LC resonator per unit optical power.

However, coupling these types of optical reception elements to KIDs is a challenge because of the impedance mismatch between the microstrip transmission line exiting these architectures and the high resistivity of titanium nitride. Mitigating direct absorption of light through free space coupling to the inductor of KID is another challenge. We present a detailed titanium nitride KID design that addresses these challenges. The KID inductor is capacitively coupled to the microstrip in such a way as to form a lossy termination without creating an impedance mismatch. A parallel plate capacitor design mitigates direct absorption, uses hydrogenated amorphous silicon, and yields acceptable noise. We show that the optimized design can yield expected sensitivities very close to the fundamental limit for a long wavelength imager (LWCam) that covers six spectral bands from 90 to 400 GHz for SZE studies.

Excess phase (frequency) noise has been observed in KID and is very likely caused by two-level systems (TLS) in dielectric materials. The TLS hypothesis is supported by the measured dependence of the noise on resonator internal power and temperature. However, there is still a lack of a unified microscopic theory which can quantitatively model the properties of the TLS noise. In this thesis we derive the noise power spectral density due to the coupling of TLS with phonon bath based on an existing model and compare the theoretical predictions about power and temperature dependences with experimental data. We discuss the limitation of such a model and propose the direction for future study.

El fraude empresarial: perspectiva internacional

Este trabajo analiza el fraude empresarial desde una perspectiva internacional. En los últimos años, ha estado muy presente en casos como el de Enron, WorldCom, Royal Ahold o PARMALAT, en los que se ven afectados la propia empresa, los trabajadores, el gobierno y, especialmente, los inversores, con pérdidas que pueden alcanzar millones de dólares. El fraude también afecta a la imagen de las empresas y en la motivación de los trabajadores, y además a menudo es causa de denuncias y penas de prisión. En función del tamaño de la empresa y del sector, la frecuencia con la que se cometen los actos fraudulentos y las pérdidas causadas varían. Asimismo, estos fraudes afectan a todas las regiones del mundo, aunque de manera desigual. Pero es en aquellas regiones más desarrolladas donde se le presta más atención al tema, y donde se han tomado numerosas medidas para intentar impedir estos actos ilícitos. Algunas de las más importantes son las propuestas por las Naciones Unidas: El Pacto Mundial y la Convención contra la Corrupción. También cabe destacar la Oficina Europea de Lucha Contra el Fraude, a nivel europeo, o la Foreign Corrupt Practices Act y la Ley Sarbanes-Oxley, en Estados Unidos. A pesar de estas medidas, en los últimos años el nivel de fraude ha aumentado.

On the interaction of actinomycin and DNA

Experiments have been accomplished that (a) further define the nature of the strong, G-containing DNA binding sites for actinomycin D (AMD), and (b) quantitate the in vitro inhibition of E. coli RNA polymerase activity by T7 DNA-bound AMD.

Twenty-five to forty percent of the G's of crab dAT are disallowed as strong AMD binding sites. The G's are measured to be randomly distributed, and, therefore, this datum cannot be explained on the basis of steric interference alone. Poly dAC:TG binds as much AMD and as strongly as any natural DNA, so the hypothesis that the unique strong AMD binding sites are G and a neighboring purine is incorrect. The datum can be explained on the basis of both steric interference and the fact that TGA is a disallowed sequence for strong AMD binding.

Using carefully defined in vitro conditions, there is one RNA synthesized per T7 DNA by E. coli RNA polymerase. The rate of the RNA polymerase-catalyzed reaction conforms to the equation 1/rate = 1/k_A(ATP) + 1/K_G(GTP) + 1/K_C(CTP) + 1/K_U(UTP) T7 DNA-bound AMD has only modest effects on initiation and termination of the polymerase-catalyzed reaction, but a large inhibitory effect on propagation. In the presence of bound AMD, k_G and k_C are decreased, whereas k_A and k_U are unaffected. These facts are interpreted to mean that on the microscopic level, on the average, the rates of incorporation of ATP and UTP are the same in the absence or presence of bound AMD, but that the rates of incorporation of GTP and CTP are decreased in the presence of AMD.

Práticas contraceptivas e gestão da heterossexualidade: agência individual, contextos relacionais e gênero.

A tese versa sobre as grandes questões relativas à contracepção no Brasil. Integra um esforço por analisar condutas referentes à contracepção, segundo lógicas que priorizam a situacionalidade e a relacionalidade de tais fenômenos. As estratégias para gerir a fecundidade são constitutivas da sexualidade heterossexual. Mulheres e homens podem usar ou não contracepção; as razões dessa conduta extrapolam aspectos concernentes a informação e acesso. Busca-se compreender as práticas contraceptivas a partir do processo do aprendizado das lógicas relacionais e de gênero, em diferentes momentos dos percursos biográficos: o início da trajetória afetivo-sexual, os contextos de irrupção de uma gravidez e o encerramento da potencialidade reprodutiva, por meio da esterilização contraceptiva. Este compósito demandou a utilização de materiais empíricos distintos para a construção e análise das etapas eleitas dos percursos biográficos. Enfoca-se, primeiramente, o momento de passagem à sexualidade com parceiro. Problematiza-se a ideia de relaxamento das práticas contraceptivas, a partir da iniciação sexual, concepção corrente na literatura nacional em função do decréscimo de uso de preservativo em relações sexuais posteriores. Aborda-se, em seguida, as atitudes e as questões presentes no processo de construção da prática contraceptiva, no momento em que a vida sexual se torna regular. A proposição da perspectiva da gestão contraceptiva sublinha as posições dos protagonistas, marcadas pelo gênero. Por último, analisa-se as circunstâncias biográficas e os cenários relacionais da esterilização contraceptiva, a qual emerge como uma estratégia de estabilização ou de consolidação de um percurso contraceptivo/reprodutivo. O debate em torno da contracepção no Brasil apresenta a tendência a enfatizar a determinação social para explicar as gestações imprevistas. Contudo, salienta-se, com base em uma literatura crítica, as dimensões de agência individual, ainda que circunscritas por um campo delimitado de possibilidades.

I. A study of the dynamics of triplet excitons in molecular crystals. II. An investigation of delayed light emission from Chlorella pyrenoidosa

I. PREAMBLE AND SCOPE

Brief introductory remarks, together with a definition of the scope of the material discussed in the thesis, are given.

II. A STUDY OF THE DYNAMICS OF TRIPLET EXCITONS IN MOLECULAR CRYSTALS

Phosphorescence spectra of pure crystalline naphthalene at room temperature and at 77˚ K are presented. The lifetime of the lowest triplet ³B_1u state of the crystal is determined from measurements of the time-dependence of the phosphorescence decay after termination of the excitation light. The fact that this lifetime is considerably shorter in the pure crystal at room temperature than in isotopic mixed crystals at 4.2˚ K is discussed, with special importance being attached to the mobility of triplet excitons in the pure crystal.

Excitation spectra of the delayed fluorescence and phosphorescence from crystalline naphthalene and anthracene are also presented. The equation governing the time- and spatial-dependence of the triplet exciton concentration in the crystal is discussed, along with several approximate equations obtained from the general equation under certain simplifying assumptions. The influence of triplet exciton diffusion on the observed excitation spectra and the possibility of using the latter to investigate the former is also considered. Calculations of the delayed fluorescence and phosphorescence excitation spectra of crystalline naphthalene are described.

A search for absorption of additional light quanta by triplet excitons in naphthalene and anthracene crystals failed to produce any evidence for the phenomenon. This apparent absence of triplet-triplet absorption in pure crystals is attributed to a low steady-state triplet concentration, due to processes like triplet-triplet annihilation, resulting in an absorption too weak to be detected with the apparatus used in the experiments. A comparison of triplet-triplet absorption by naphthalene in a glass at 77˚ K with that by naphthalene-h₈ in naphthalene-d₈ at 4.2˚ K is given. A broad absorption in the isotopic mixed crystal triplet-triplet spectrum has been tentatively interpreted in terms of coupling between the guest ³B_1u state and the conduction band and charge-transfer states of the host crystal.

III. AN INVESTIGATION OF DELAYED LIGHT EMISSION FROM Chlorella Pyrenoidosa

An apparatus capable of measuring emission lifetimes in the range 5 X 10^-9 sec to 6 X 10^-3 sec is described in detail. A cw argon ion laser beam, interrupted periodically by means of an electro-optic shutter, serves as the excitation source. Rapid sampling techniques coupled with signal averaging and digital data acquisition comprise the sensitive detection and readout portion of the apparatus. The capabilities of the equipment are adequately demonstrated by the results of a determination of the fluorescence lifetime of 5, 6, 11, 12-tetraphenyl-naphthacene in benzene solution at room temperature. Details of numerical methods used in the final data reduction are also described.

The results of preliminary measurements of delayed light emission from Chlorella Pyrenoidosa in the range 10^-3 sec to 1 sec are presented. Effects on the emission of an inhibitor and of variations in the excitation light intensity have been investigated. Kinetic analysis of the emission decay curves obtained under these various experimental conditions indicate that in the millisecond-to-second time interval the decay is adequately described by the sum of two first-order decay processes. The values of the time constants of these processes appear to be sensitive both to added inhibitor and to excitation light intensity.

Defect and structural imperfection effects on the electronic properties of BiTeI surfaces

The surface electronic structure of the narrow-gap seminconductor BiTeI exhibits a large Rashba-splitting which strongly depends on the surface termination. Here we report on a detailed investigation of the surface morphology and electronic properties of cleaved BiTeI single crystals by scanning tunneling microscopy, photoelectron spectroscopy (ARPES, XPS), electron diffraction (SPA-LEED) and density functional theory calculations. Our measurements confirm a previously reported coexistence of Te- and I-terminated surface areas

Comparativa entre diferencial de baja impedancia de generador y de baja impedancia de transformador.

[ES]El objetivo principal de TFG es analizar y comparar el funcionamiento de las protecciones diferenciales de baja impedancia de generador y de transformador de potencia. Para ello, se describirán sus características principales de forma teórica y se realizarán simulaciones mediante el módulo SimPowersSystems contenido en Matlab.