Sample records for material constituinte dos

  1. Teamwork in nursing: restricted to nursing professionals or an interprofessional collaboration?

    PubMed

    Souza, Geisa Colebrusco de; Peduzzi, Marina; Silva, Jaqueline Alcântara Marcelino da; Carvalho, Brígida Gimenez

    2016-01-01

    To understand the nursing professionals' conceptions of teamwork and their elements. A qualitative study conducted in an oncological hospital using a semi-structured interview with 21 nursing professionals. Two conceptions emerged from the accounts: teamwork restricted to nursing professionals and teamwork with interprofessional collaboration with particular importance for interactive dimensions: communication, trust and professional bonds, mutual respect and recognition of the other's work, collaboration, and conflict, with this last subcategory considered as an obstacle to teamwork. Nursing conceives teamwork as an interprofessional practice, which is a result of the quality of interaction among professionals from different areas and involves the recognition and handling of conflicts. Compreender as concepções dos profissionais de enfermagem sobre trabalho em equipe e seus elementos constituintes. Pesquisa qualitativa, realizada em hospital oncológico, por meio de entrevista semiestruturada com 21 profissionais de enfermagem. Duas concepções emergiram dos relatos, trabalho em equipe circunscrito à enfermagem e trabalho em equipe com colaboração interprofissional, com destaque para dimensão interativa: comunicação, confiança e vínculo, respeito mútuo e reconhecimento do trabalho do outro, colaboração e conflito. Esta última subcategoria foi apontada como obstáculo para o trabalho em equipe. A enfermagem concebe majoritariamente o trabalho em equipe como ação interprofissional, e isto decorre da qualidade da interação entre os profissionais das diferentes áreas e o reconhecimento e manejo de conflitos.

  2. Brevipalpus phoenicis (Geijskes) sensu lato (Acari:Tenuipalpidae) no Brasil

    USDA-ARS?s Scientific Manuscript database

    Os ácaros tenuipalpídeos ou ácaros planos são importantes fitófagos constituintes do agroecossistema e florestas semitropical e tropical (JEPPSON et al., 1975; HOY, 2011), sendo que algumas espécies estão associadas à transmissão de fitovírus (CHAGAS et al., 2001 e 2003; CHILDERS et al., 2001; KITAJ...

  3. A Direct Method to Extract Transient Sub-Gap Density of State (DOS) Based on Dual Gate Pulse Spectroscopy

    NASA Astrophysics Data System (ADS)

    Dai, Mingzhi; Khan, Karim; Zhang, Shengnan; Jiang, Kemin; Zhang, Xingye; Wang, Weiliang; Liang, Lingyan; Cao, Hongtao; Wang, Pengjun; Wang, Peng; Miao, Lijing; Qin, Haiming; Jiang, Jun; Xue, Lixin; Chu, Junhao

    2016-06-01

    Sub-gap density of states (DOS) is a key parameter to impact the electrical characteristics of semiconductor materials-based transistors in integrated circuits. Previously, spectroscopy methodologies for DOS extractions include the static methods, temperature dependent spectroscopy and photonic spectroscopy. However, they might involve lots of assumptions, calculations, temperature or optical impacts into the intrinsic distribution of DOS along the bandgap of the materials. A direct and simpler method is developed to extract the DOS distribution from amorphous oxide-based thin-film transistors (TFTs) based on Dual gate pulse spectroscopy (GPS), introducing less extrinsic factors such as temperature and laborious numerical mathematical analysis than conventional methods. From this direct measurement, the sub-gap DOS distribution shows a peak value on the band-gap edge and in the order of 1017-1021/(cm3·eV), which is consistent with the previous results. The results could be described with the model involving both Gaussian and exponential components. This tool is useful as a diagnostics for the electrical properties of oxide materials and this study will benefit their modeling and improvement of the electrical properties and thus broaden their applications.

  4. 77 FR 14581 - Notice of Meeting of the Cultural Property Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-12

    ... DEPARTMENT OF STATE [Public Notice 7767; Guatemala Docket No. DOS-2012-0011; Mali Docket No. DOS... Government of the Republic of Guatemala Concerning the Imposition of Import Restrictions on Archaeological Objects and Materials from the Pre- Columbian Cultures of Guatemala (MOU) [Docket No. DOS-2012-0011] and...

  5. 48 CFR 632.702-70 - DOS policy.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false DOS policy. 632.702-70... REQUIREMENTS CONTRACT FINANCING Contract Funding 632.702-70 DOS policy. The Department's policy is to provide... incremental funding of cost-reimbursement contracts. Fixed-price, labor-hour, and time-and-materials contracts...

  6. 76 FR 76476 - Notice of Meeting of the Cultural Property Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-07

    ... DEPARTMENT OF STATE [Public Notice 7658; Cyprus Docket No. DOS-2011-0135; Peru Docket No. DOS-2011... Ritual Ethnological Material [Docket No. DOS-2011-0135], and with Peru Memorandum of Understanding Between the Government of the United States of America and the Government of the Republic of Peru...

  7. JPRS Report, West Europe, Reference Aid, Acronyms and Abbreviations of Portugal

    DTIC Science & Technology

    1988-09-02

    Internacional, Ltd. AML Auto Metralhadora Ligeira AN Assembleia Nacional ANA Aeroportos e Navegacao Aerea ANASD ^ Associacao Nacional dos...de Informacoes ANIC ^ Associacao Nacional dos Industriais de Conservas ANIMEE Associac’ao Nacional dos Industriais de Material Electrico e...Produtos Electricos SIPIP ^ Servico de Informacao Previa ao Investidor Potencial SIRP ^ Sistema de Informac’oes da Repüblica Portuguesa SIS

  8. Thin films for gas sensors

    NASA Astrophysics Data System (ADS)

    Pires, Jose Miguel Alves Correia

    Nos ultimos anos tem-se assistido a um aumento dos investimentos na investigacao de novos materiais para aplicacao em sensores. Apesar de ja existir um bom numero de dispositivos explorados comercialmente, muitas vezes, quer devido aos elevados custos de producao, quer devido a uma crescente exigencia do ponto de vista das caracteristicas de funcionamento, continua a ser necessario procurar novos materiais ou novas formas de producao que permitam baixar os custos e melhorar o desempenho dos dispositivos. No campo dos sensores de gases tem-se verificado continuos avancos nos ultimos anos. Continua todavia a ser necessario conhecer melhor, tanto os processos de producao dos materiais, como os mecanismos que regulam a sensibilidade dos dispositivos aos gases, de modo a orientar adequadamente a investigacao dos novos materiais, nomeadamente no que se refere a optimizacao dos parâmetros que nao satisfazem ainda os requisitos do mercado. Um dos materiais que tem mostrado melhores qualidades para aplicacao em sensores de gases de tipo resistivo e o dioxido de estanho. Este material tem sido produzido sob diversas formas e usando diferentes tecnicas, como sejam: sol-gel [1], pulverizacao catodica (sputtering) por magnetrao [2-4], sinterizacao de pos [5, 6], ablacao laser [7] ou RGTO [8]. Os resultados obtidos revelam que as caracteristicas dos dispositivos sao muito dependentes das tecnicas usadas na sua producao. A deposicao usando sputtering reactivo por magnetrao e uma tecnica que permite obter filmes finos de oxido de estanho com diferentes caracteristicas, quer do ponto de vista da estrutura, quer da composicao, e por isso, tambem, com diferentes sensibilidades aos gases. No âmbito deste trabalho, foram produzidos filmes de SnO2 usando sputtering DC reactivo com diferentes condicoes de deposicao. Os substratos usados foram lâminas de vidro e o alvo foi estanho com 99.9% de pureza. Foi estudada a influencia da atmosfera de deposicao, da pressao parcial do O2, da temperatura do substrato e da potencia da descarga na estrutura do material depositado. Durante a deposicao, alem dos parâmetros ja referidos, foram tambem registados a pressao de base antes da entrada dos gases de sputtering, os fluxos de oxigenio e argon durante a deposicao, a distância alvo-substrato, o tempo de deposicao, a corrente e a tensao aplicadas ao magnetrao. Foram feitas algumas experiencias usando uma fonte RF, para comparacao. (Abstract shortened by ProQuest.).

  9. Transient many-body instability in driven Dirac materials

    NASA Astrophysics Data System (ADS)

    Pertsova, Anna; Triola, Christopher; Balatsky, Alexander

    The defining feature of a Dirac material (DM) is the presence of nodes in the low-energy excitation spectrum leading to a strong energy dependence of the density of states (DOS). The vanishing of the DOS at the nodal point implies a very low effective coupling constant which leads to stability of the node against electron-electron interactions. Non-equilibrium or driven DM, in which the DOS and hence the effective coupling can be controlled by external drive, offer a new platform for investigating collective instabilities. In this work, we discuss the possibility of realizing transient collective states in driven DMs. Motivated by recent pump-probe experiments which demonstrate the existence of long-lived photo-excited states in DMs, we consider an example of a transient excitonic instability in an optically-pumped DM. We identify experimental signatures of the transient excitonic condensate and provide estimates of the critical temperatures and lifetimes of these states for few important examples of DMs, such as single-layer graphene and topological-insulator surfaces.

  10. Interband coupling and transport interband scattering in s ± superconductors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kogan, Vladimir; Prozorov, Ruslan

    A two-band model with repulsive interband coupling and interband transport (potential) scattering is considered to elucidate their effects on material properties. In agreement with previous work, we find that the bands order parameters Δ 1,2 differ and the large is at the band with a smaller normal density of states (DOS), N n2 < N n1. However, the bands energy gaps, as determined by the energy dependence of the DOS, are equal due to scattering. For each temperature, the gaps turn zero at a certain critical interband scattering rate, i.e. for strong enough scattering the model material becomes gappless. Inmore » the gapless state, the DOS at the band 2 is close to the normal state value, whereas at the band 1 it has a V-shape with non-zero minimum. When the normal bands DOS' are mismatched, N n1 6= N n2, the critical temperature T c is suppressed even in the absence of interband scattering, T c(N n1) has a dome-like shape. With increasing interband scattering, the London penetration depth at low temperatures evolves from being exponentially at to the powerlaw and even to near linear behavior in the gapless state, the latter being easily misinterpreted as caused by order parameter nodes.« less

  11. Scanning tunneling spectroscopy of MoS2 monolayer in presence of ethanol gas

    NASA Astrophysics Data System (ADS)

    Hosseini, Seyed Ali; Iraji zad, Azam; Berahman, Masoud; Aghakhani Mahyari, Farzaneh; Shokouh, Seyed Hossein Hosseini

    2018-04-01

    Due to high surface to volume ratio and tunable band gap, two dimensional (2D) layered materials such as MoS2, is good candidate for gas sensing applications. This research mainly focuses on variation of Density of States (DOS) of MoS2 monolayes caused by ethanol adsorption. The nanosheets are synthesized by liquid exfoliation, and then using Scanning Tunneling Spectroscopy (STS) and Density Functional Theory (DFT), local electronic characteristic such as DOS and band gap in non-vacuum condition are analyzed. The results show that ethanol adsorption enhances DOS and deform orbitals near the valence and conduction bands that increase transport of carriers on the sheet.

  12. Enhanced thermoelectric performance of β-Zn4Sb3 based nanocomposites through combined effects of density of states resonance and carrier energy filtering.

    PubMed

    Zou, Tianhua; Qin, Xiaoying; Zhang, Yongsheng; Li, Xiaoguang; Zeng, Zhi; Li, Di; Zhang, Jian; Xin, Hongxing; Xie, Wenjie; Weidenkaff, Anke

    2015-12-15

    It is a major challenge to elevate the thermoelectric figure of merit ZT of materials through enhancing their power factor (PF) and reducing the thermal conductivity at the same time. Experience has shown that engineering of the electronic density of states (eDOS) and the energy filtering mechanism (EFM) are two different effective approaches to improve the PF. However, the successful combination of these two methods is elusive. Here we show that the PF of β-Zn4Sb3 can greatly benefit from both effects. Simultaneous resonant distortion in eDOS via Pb-doping and energy filtering via introduction of interface potentials result in a ~40% increase of PF and an approximately twofold reduction of the lattice thermal conductivity due to interface scattering. Accordingly, the ZT of β-Pb0.02Zn3.98Sb3 with 3 vol.% of Cu3SbSe4 nanoinclusions reaches a value of 1.4 at 648 K. The combination of eDOS engineering and EFM would potentially facilitate the development of high-performance thermoelectric materials.

  13. Mechanoelectrically Activated Synthesis of Dense, Bulk Nanostructured, Complex Crystalline and Glassy Hard Materials

    DTIC Science & Technology

    2005-04-01

    Facultad de Quimica , Universidad Autonoma de Queretaro, Queretaro, Mexico, May 7, 2002. (Invited Seminar) "* Recent Advances in the Synthesis and...A. Munir, 14o Congresso Brasileiro de Engenharia e Ciencias dos Materiais (14th Brazilian Congress on Materials Science and Engineering), Sao Pedro

  14. Forms of Appropriation of Tools for the Astronomy Education in Continuous Training of Teachers. (Spanish Title: Formas de Apropriación de Herramientas Para la Enseñanza de la Astronomía en la Formación Docente Continua.) Formas de Apropriação de Instrumentos Para o Ensino de Astronomia na Formação Continuada de Professores

    NASA Astrophysics Data System (ADS)

    Marques Soares, Leonardo; Sousa Nascimento, Silvania

    2012-07-01

    The main focus of this article is to present some impressions about the way some teachers appropriated of the tools from the ASTRONOMY TEACHING KIT (KITPEA). The subjects of this research were teachers that took part in the astronomy teaching specialization course offered by the Continuing Education Project (FOCO) at Math and Science Teaching Center (CECIMIG) from the School of Education of Federal University of Minas Gerais (FaE/UFMG). The data was collected with the use of a questionnaire and of an interview applied to these teachers. The analysis of the data was structured with the aid of the Activity Theory and the Mediated Action Theory. We interpret the teachers' speech using the constitutive aspects of the activity system and the concepts of appropriation and domain as an analytical device. It was possible to recognize the appropriation of the tools in 7 narratives among the 11 individuals who took part in the research. El objetivo principal de ese artículo es presentar indicaciones sobre la manera como algunos maestros se apropiaron de las herramientas del KIT PARA LA ENSEÑANZA DE LA ASTRONOMÍA (KITPEA). Los sujetos de esa investigación son docentes que participaron del curso de especialización en enseñanza de astronomía ofrecido por el Proyecto de Formación Continua (Foco) en el Centro de Enseñanza de Ciencias y Matemática (CECIMIG) de la Facultad de Educación de la Universidad Federal de Minas Gerais (FaE/UFMG). Recogimos las informaciones a través de un cuestionario y de una encuesta, aplicados a esos docentes. Estructuramos el análisis de esas informaciones con la ayuda de la Teoría de la Actividad y de la Teoría de la Acción Mediada. Interpretamos os discursos de los docentes usando como dispositivo analítico los elementos constitutivos del sistema de actividad y los conceptos apropiación y dominio. Entre los 11 sujetos que participaron de la investigación, fue posible interpretar con claridad la apropiación de las herramientas en siete relatos. O objetivo principal desse artigo é apresentar algumas reflexões sobre a maneira como um grupo de professores se apropriaram dos instrumentos do KIT PARA O ENSINO DE ASTRONOMIA (KITPEA). Os sujeitos dessa pesquisa participaram do curso de especialização em ensino de astronomia oferecido pelo Projeto de Formação Continuada (Foco) no Centro de Ensino de Ciências e Matemática (CECIMIG) da Faculdade de Educação da Universidade Federal de Minas Gerais (FaE/UFMG). Coletamos as informações por meio de um questionário e de uma entrevista, aplicados a esses professores. Estruturamos a análise dessas informações com a ajuda da Teoria da Atividade e da Teoria da Ação Mediada. Interpretamos as falas dos professores usando como dispositivo analítico os elementos constituintes do sistema de atividade e os conceitos de apropriação e domínio. Dentre os 11 sujeitos que participaram da pesquisa, foi possível identificar a apropriação dos instrumentos em 7 narrativas.

  15. Precipitation Phenomena: Deformation and Aging. Proceedings of an International Conference Held in Conjunction with the 1988 World Materials Congress, Chicago, Illinois, USA, 24-30 September 1988

    DTIC Science & Technology

    1988-01-01

    corrosion and stress analytical methods. corrosion cracking (SCC) in certain aqueous 3 EXPERIMENTAL PROCEDURE treatments were performed using variable time...properly oriented with the applied uniaxial approach a comparable EPR-DOS in the control stress are influenced. Deformation may specimens. EPR-DOS values...corrosion and stress corrosion. Atteridge, Sensitization Development Deformation above 20% prior strain, however, in Austenitic Stainless Steel: II. induces

  16. Monte Carlo Calculation of Thermal Neutron Inelastic Scattering Cross Section Uncertainties by Sampling Perturbed Phonon Spectra

    NASA Astrophysics Data System (ADS)

    Holmes, Jesse Curtis

    Nuclear data libraries provide fundamental reaction information required by nuclear system simulation codes. The inclusion of data covariances in these libraries allows the user to assess uncertainties in system response parameters as a function of uncertainties in the nuclear data. Formats and procedures are currently established for representing covariances for various types of reaction data in ENDF libraries. This covariance data is typically generated utilizing experimental measurements and empirical models, consistent with the method of parent data production. However, ENDF File 7 thermal neutron scattering library data is, by convention, produced theoretically through fundamental scattering physics model calculations. Currently, there is no published covariance data for ENDF File 7 thermal libraries. Furthermore, no accepted methodology exists for quantifying or representing uncertainty information associated with this thermal library data. The quality of thermal neutron inelastic scattering cross section data can be of high importance in reactor analysis and criticality safety applications. These cross sections depend on the material's structure and dynamics. The double-differential scattering law, S(alpha, beta), tabulated in ENDF File 7 libraries contains this information. For crystalline solids, S(alpha, beta) is primarily a function of the material's phonon density of states (DOS). Published ENDF File 7 libraries are commonly produced by calculation and processing codes, such as the LEAPR module of NJOY, which utilize the phonon DOS as the fundamental input for inelastic scattering calculations to directly output an S(alpha, beta) matrix. To determine covariances for the S(alpha, beta) data generated by this process, information about uncertainties in the DOS is required. The phonon DOS may be viewed as a probability density function of atomic vibrational energy states that exist in a material. Probable variation in the shape of this spectrum may be established that depends on uncertainties in the physics models and methodology employed to produce the DOS. Through Monte Carlo sampling of perturbations from the reference phonon spectrum, an S(alpha, beta) covariance matrix may be generated. In this work, density functional theory and lattice dynamics in the harmonic approximation are used to calculate the phonon DOS for hexagonal crystalline graphite. This form of graphite is used as an example material for the purpose of demonstrating procedures for analyzing, calculating and processing thermal neutron inelastic scattering uncertainty information. Several sources of uncertainty in thermal neutron inelastic scattering calculations are examined, including sources which cannot be directly characterized through a description of the phonon DOS uncertainty, and their impacts are evaluated. Covariances for hexagonal crystalline graphite S(alpha, beta) data are quantified by coupling the standard methodology of LEAPR with a Monte Carlo sampling process. The mechanics of efficiently representing and processing this covariance information is also examined. Finally, with appropriate sensitivity information, it is shown that an S(alpha, beta) covariance matrix can be propagated to generate covariance data for integrated cross sections, secondary energy distributions, and coupled energy-angle distributions. This approach enables a complete description of thermal neutron inelastic scattering cross section uncertainties which may be employed to improve the simulation of nuclear systems.

  17. Development and Application of New Solid-State Models for Low-Energy Vibrations, Lattice Defects, Entropies of Mixing, and Magnetic Properties

    NASA Astrophysics Data System (ADS)

    Schliesser, Jacob M.

    Low-temperature heat capacity data contain information on the physical properties of materials, and new models continue to be developed to aid in the analysis and interpretation of heat capacity data into physically meaningful properties. This work presents the development of two such models and their application to real material systems. Equations describing low-energy vibrational modes with a gap in the density of states (DOS) have been derived and tested on several material systems with known gaps in the DOS, and the origins of such gaps in the DOS are presented. Lattice vacancies have been shown to produce a two-level system that can be modeled with a sum of low-energy Schottky anomalies that produce an overall linear dependence on temperature in the low-temperature heat capacity data. These two models for gaps in the vibrational DOS and the relationship between a linear heat capacity and lattice vacancies and many well-known models have been applied to several systems of materials to test their validity and applicability as well as provide greater information on the systems themselves. A series of bulk and nanoscale Mn-Fe and Co-Fe spinel solid solutions were analyzed using the entropies derived from heat capacity data, and excess entropies of mixing were determined. These entropies show that changes in valence, cation distribution, bonding, and the microstructure between the mixing ions is non-ideal, especially in the nanoparticles. The heat capacity data of ten Al doped TiO2 anatase nanoparticle samples have also been analyzed to show that the Al3+ dopant ions form small regions of short-range order, similar to a glass, within the TiO2 particles, while the overall structure of TiO2 remains unchanged. This has been supported by X-ray diffraction (XRD) and electron energy-loss spectroscopy and provides new insights to the synthesis and characterization of doped materials. The final investigation examines nanocrystalline CuO using heat capacities, magnetization, XRD, and electron microscopy and compares the findings to the known properties of bulk CuO. All of these measurements show transitions between antiferromagnetic and paramagnetic states in the temperature range of about 150--350 K that are greater in number and higher in temperature than the transitions in bulk CuO. These changes are shown to cause an increase in the temperature range of multiferroicity in CuO nanoparticles. Keywords: thermodynamics, heat capacity, lattice vacancies, materials, nanoparticles, mixing, characterization.

  18. Morphometric and bioacoustic data on three species of Pseudopaludicola Miranda-Ribeiro, 1926 (Anura: Leptodactylidae: Leiuperinae) described from Chapada dos Guimarães, Mato Grosso, Brazil, with the revalidation of Pseudopaludicola ameghini (Cope, 1887).

    PubMed

    Pansonato, André; Strüssmann, Christine; Mudrek, Jessica Rhaiza; Martins, Itamar Alves

    2013-01-01

    Due to minute size, overall morphological similarities, scarcity of diagnostic characters after preservation, and usual sympatric or even syntopic occurrence of two or more species of Pseudopaludicola, the taxonomy of the genus is not yet a matter of consensus. Three species in the genus Pseudopaludicola Miranda-Ribeiro, 1926 were described by Cope in 1887, based on material obtained at Chapada dos Guimarães, mid-western state of Mato Grosso, Brazil. One of these species, Pseudopaludicola ameghini, was subsequently synonymized to P. mystacalis. In this paper we present morphological and bioacoustic evidences supporting a full specific status for the three sympatric species of Pseudopaludicola described from Chapada dos Guimarães, including Pseudopaludicola ameghini Cope, 1887.

  19. Effect of substitutional defects on Kambersky damping in L10 magnetic materials

    NASA Astrophysics Data System (ADS)

    Qu, T.; Victora, R. H.

    2015-02-01

    Kambersky damping, representing the loss of magnetic energy from the electrons to the lattice through the spin orbit interaction, is calculated for L10 FePt, FePd, CoPt, and CoPd alloys versus chemical degree of order. When more substitutional defects exist in the alloys, damping is predicted to increase due to the increase of the spin-flip channels allowed by the broken symmetry. It is demonstrated that this corresponds to an enhanced density of states (DOS) at the Fermi level, owing to the rounding of the DOS with loss of long-range order. Both the damping and the DOS of the Co-based alloy are found to be less affected by the disorder. Pd-based alloys are predicted to have lower damping than Pt-based alloys, making them more suitable for high density spintronic applications.

  20. Extraction of the defect density of states in microcrystalline silicon from experimental results and simulation studies

    NASA Astrophysics Data System (ADS)

    Tibermacine, T.; Merazga, A.; Ledra, M.; Ouhabab, N.

    2015-09-01

    The constant photocurrent method in the ac-mode (ac-CPM) is used to determine the defect density of states (DOS) in hydrogenated microcrystalline silicon (μc-Si:H) prepared by very high frequency plasma-enhanced chemical vapor deposition (VHF-PECVD). The absorption coefficient spectrum (ac-α(hv)), is measured under ac-CPM conditions at 60 Hz. The measured ac-α(hv) is converted by the CPM spectroscopy into a DOS distribution covering a portion in the lower energy range of occupied states. We have found that the density of valence band-tail states falls exponentially towards the gap with a typical band-tail width of 63 meV. Independently, computer simulations of the ac-CPM are developed using a DOS model that is consistent with the measured ac-α(hv) in the present work and a previously measured transient photocurrent (TPC) for the same material. The DOS distribution model suggested by the measurements in the lower and in the upper part of the energy-gap, as well as by the numerical modelling in the middle part of the energy-gap, coincide reasonably well with the real DOS distribution in hydrogenated microcrystalline silicon because the computed ac-α(hv) is found to agree satisfactorily with the measured ac-α(hv).

  1. Production and characterization of a camelid single domain antibody-urease enzyme conjugate for the treatment of cancer.

    PubMed

    Tian, Baomin; Wong, Wah Yau; Hegmann, Elda; Gaspar, Kim; Kumar, Praveen; Chao, Heman

    2015-06-17

    A novel immunoconjugate (L-DOS47) was developed and characterized as a therapeutic agent for tumors expressing CEACAM6. The single domain antibody AFAIKL2, which targets CEACAM6, was expressed in the Escherichia coli BL21 (DE3) pT7-7 system. High purity urease (HPU) was extracted and purified from Jack bean meal. AFAIKL2 was activated using N-succinimidyl [4-iodoacetyl] aminobenzoate (SIAB) as the cross-linker and then conjugated to urease. The activation and conjugation reactions were controlled by altering pH. Under these conditions, the material ratio achieved conjugation ratios of 8-11 antibodies per urease molecule, the residual free urease content was practically negligible (<2%), and high purity (>95%) L-DOS47 conjugate was produced using only ultradiafiltration to remove unreacted antibody and hydrolyzed cross-linker. L-DOS47 was characterized by a panel of analytical techniques including SEC, IEC, Western blot, ELISA, and LC-MS(E) peptide mapping. As the antibody-urease conjugate ratio increased, a higher binding signal was observed. The specificity and cytotoxicity of L-DOS47 was confirmed by screening in four cell lines (BxPC-3, A549, MCF7, and CEACAM6-transfected H23). BxPC-3, a CEACAM6-expressing cell line was found to be most susceptible to L-DOS47. L-DOS47 is being investigated as a potential therapeutic agent in human phase I clinical studies for nonsmall cell lung cancer.

  2. Contribution to the scintillation detection optimization in double phase detectors for direct detection of dark matter

    NASA Astrophysics Data System (ADS)

    Balan, Catalin

    Na ultima decada, foram feitos grandes progressos no desenvolvimento dos detetores de detecao direta das particulas que constituem a materia negra. Com estrategias do aumento gradual do volume do alvo e, simultaneamente, de reducao dos niveis de fundo, a experiencia XENON obteve resultados muito bons e perspetivas promissoras para a detecao de materia negra. Tarefas relativas a analise de dados experimentais adquiridos com o detetor de dupla fase em uso, assim como as simulacoes do campo eletrico, desenvolvimento, montagem e testes para o proximo detetor XENON1T, assim como a participacao regular na manutencao geral e monitorizacao do prototipo atual XENON100 no LNGS, constituiram o plano de trabalhos para as atividades de investigacao do presente doutoramento e a minha contribuicao para a otimizacao da detecao de cintilacao nos detetores da experiencia XENON. A necessidade de alcancar niveis elevados de sensibilidade, requer inovacao em todos os aspetos fisicos do detetor, assim como a reducao de todas as fontes de radioatividade que contribuem para o fundo. O modo mais indicado de operacao para os detetores com enchimento a Xe no estado liquido e gasoso envolve a medicao da cintilacao primaria e da secundaria provenientes da interacao das particulas no Xe liquido. A razao entre estes dois sinais permite diferenciar claramente a maior parte dos eventos correspondentes as fundo dos eventos correspondentes a WIMPs. Deste modo, a leitura dos sinais correspondentes a cintilacao e de extrema importancia. A amplitude do sinal de cintilacao antes dos fotossensores e maximizada atraves da otimizacao de varios parametros, tais como a geometria do alvo do detetor, a transparencia das grelhas dos eletrodos, a uniformidade do ganho em cintilacao secundaria e a utilizacao de material reflectivo para cobrir as superficies que nao sao fotossensiveis.

  3. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cochran, John Russell

    The Al Tuwaitha nuclear complex near Baghdad contains a number of facilities from Saddam Hussan's nuclear weapons program. Past military operations, lack of upkeep and looting have created an enormous radioactive waste problem at the Al Tuwaitha complex, which contains various, uncharacterized radioactive wastes, yellow cake, sealed radioactive sources, and contaminated metals that must be constantly guarded. Iraq has never had a radioactive waste disposal facility and the lack of a disposal facility means that ever increasing quantities of radioactive material must be held in guarded storage. The Iraq Nuclear Facility Dismantlement and Disposal Program (the NDs Program) has beenmore » initiated by the U.S. Department of State (DOS) to assist the Government of Iraq (GOI) in eliminating the threats from poorly controlled radioactive materials, while building human capacities so that the GOI can manage other environmental cleanups in their country. The DOS is funding the IAEA to provide technical assistance via Technical Cooperation projects. Program coordination will be provided by the DOS, consistent with GOI policies, and Sandia National Laboratories will be responsible for coordination of participants and waste management support. Texas Tech University will continue to provide in-country assistance, including radioactive waste characterization and the stand-up of the Iraq Nuclear Services Company. The GOI owns the problems in Iraq and will be responsible for implementation of the NDs Program.« less

  4. Molecular Library Synthesis Using Complex Substrates: Expanding the Framework of Triterpenoids

    PubMed Central

    Ignatenko, Vasily A.; Han, Yong; Tochtrop, Gregory P.

    2013-01-01

    The remodelling of a natural product core framework by means of diversity-oriented synthesis (DOS) is a valuable approach to access diverse/biologically relevant chemical space and to overcome the limitations of combinatorial-type compounds. Here we provide proof of principle and a thorough conformational analysis for a general strategy whereby the inherent complexity of a starting material is used to define the regio- and stereochemical outcomes of reactions in chemical library construction. This is in contrast to the traditional DOS logic employing reaction development and catalysis to drive library diversity PMID:23245400

  5. Effect of substitutional defects on Kambersky damping in L1{sub 0} magnetic materials

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Qu, T.; Victora, R. H., E-mail: victora@umn.edu; Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota 55455

    2015-02-16

    Kambersky damping, representing the loss of magnetic energy from the electrons to the lattice through the spin orbit interaction, is calculated for L1{sub 0} FePt, FePd, CoPt, and CoPd alloys versus chemical degree of order. When more substitutional defects exist in the alloys, damping is predicted to increase due to the increase of the spin-flip channels allowed by the broken symmetry. It is demonstrated that this corresponds to an enhanced density of states (DOS) at the Fermi level, owing to the rounding of the DOS with loss of long-range order. Both the damping and the DOS of the Co-based alloymore » are found to be less affected by the disorder. Pd-based alloys are predicted to have lower damping than Pt-based alloys, making them more suitable for high density spintronic applications.« less

  6. Band structure modification of the thermoelectric Heusler-phase TiFe2Sn via Mn substitution.

    PubMed

    Zou, Tianhua; Jia, Tiantian; Xie, Wenjie; Zhang, Yongsheng; Widenmeyer, Marc; Xiao, Xingxing; Weidenkaff, Anke

    2017-07-19

    Doping (or substitution)-induced modification of the electronic structure to increase the electronic density of states (eDOS) near the Fermi level is considered as an effective strategy to enhance the Seebeck coefficient, and may consequently boost the thermoelectric performance. Through density-functional theory calculations of Mn-substituted TiFe 2-x Mn x Sn compounds, we demonstrate that the d-states of the substituted Mn atoms induce a strong resonant level near the Fermi energy. Our experimental results are in good agreement with the calculations. They show that Mn substitution results in a large increase of the Seebeck coefficient, arising from an enhanced eDOS in Heusler compounds. The results prove that a proper substitution position and element selection can increase the eDOS, leading to a higher Seebeck coefficient and thermoelectric performance of ecofriendly materials.

  7. Luminescent sensing of Cu2+, CrO42- and photocatalytic degradation of methyl violet by Zn(II) metal-organic framework (MOF) having 5,5‧-(1H-2,3,5-triazole-1,4-diyl)diisophthalic acid ligand

    NASA Astrophysics Data System (ADS)

    Wu, Weiping; Li, Baohong; Gu, Chuying; Wang, Jun; Singh, Amita; Kumar, Abhinav

    2017-11-01

    A porous Zn(II) metal-organic framework (MOF) [Zn(H2L)(4,4‧-bipy)0.5]n (1) has been selected and its luminescence sensing for cations and anions as well as the photocatalytic property against methyl violet have been explored. Luminescence studies indicated that 1 could be an efficient multifunctional fluorescent material for highly sensitive detection of metal cation Cu2+ and anions CrO42-. The luminescence intensity of 1 was found to decrease proportionately with increase in the concentration of Cu2+ and CrO42-. Furthermore, the photocatalytic property of 1 for degradation of the methyl violet (MV) have been explored and a possible photocatalytic mechanism have been proposed using density of states (DOS) and partial DOS (pDOS) calculations.

  8. Area Handbook Series: Portugal, A Country Study

    DTIC Science & Technology

    1993-01-01

    result of their excessive dependence on debt financing, Quimigal and Setenave, as well as Companhia Nacional de Petro- quimica (CNP), a state-owned...Gerais de Material de Engenharia (OGME) for the overhaul of military vehicles; and Oficinas Gerais de Material Aeronautico (OGMA) for maintenance and...CNP. See Companhia Nacional de Petro- (CCP). See Portuguese Confederation quimica of Commerce coal, 149 Confederaqio Geral dos Trabalhadores coastline

  9. Geochemistry and genesis of the angrites

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mittlefehldt, D.W.; Lindstrom, M.M.

    1990-11-01

    The angrites Angra dos Reis, LEW86010, and LEW87051 are petrologically and compositionally similar achondrites. All angrites have high FeO/MnO ratios of 80-94 and very low CI normalized Na/Sm ratios of 0.001-0.003. High abundances of oxidized Fe and low abundances of moderately volatile Na most likely resulted from parent body processes, such as magmatic outgassing, rather than nebular processes. All angrites have fractionated Ca/Al ratios, with Angra dos Reis exhibiting the most extreme ratio (3.1 {times} CI). For Angra dos Reis, cumulus material may be the cause of the high Ca/Al ratio. Refractory element abundances of LEW86010 and LEW87051 show similarmore » patterns, while Angra dos Reis has both greater enrichments in these elements and more fractionated patterns. Compositional and petrologic constraints indicate that LEW86010 and LEW87051 are related via olivine control. The refractory element abundances and mg{number sign} of LEW86010 can be approximated by removal of olivine from LEW87051, suggesting that LEW86010 may be a residual melt from a LEW87051-like precursor. Alternatively, LEW87051 may have formed via olivine accumulation from a LEW86010-like precursor. The differences between the LEW86010-LEW87051 duo and Angra dos Reis suggest that either the angrite parent body was heterogeneous or that Angra dos Reis was formed on a separate parent body. Based on FeO/MnO ratios and normative mineralogies, the angrite parent body(ies) may be similar in bulk composition to one of the carbonaceous chondrite groups, particularly CI-CM-CO.« less

  10. Comparing Reactivation Behavior of TIG and Laser Beam Welded Alloy 690

    NASA Astrophysics Data System (ADS)

    Abraham, Geogy J.; Bhambroo, Rajan; Kain, V.; Dey, G. K.; Raja, V. S.

    2013-02-01

    The nickel base Alloy 690 was subjected to simulated autogenous welding treatment employing two different techniques, laser beam welding (LBW) and tungsten inert gas (TIG) welding. The resultant weld fusion zone (WFZ) and heat-affected zone (HAZ) were compared by studying the reactivation behavior. The chromium depletion effect was assessed by measuring the degree of sensitization (DOS) from the electrochemical potentiodynamic reactivation (EPR) test. A double-loop EPR test for Alloy 690 was employed to measure the DOS at different regions of weldments by masking the remaining regions. The results clearly demonstrated that Alloy 690 showed no sensitization in the parent material and the WFZ region of both TIG and laser weldments. However, it exhibited reactivation in the HAZ region of both the weldments. The DOS values measured for Alloy 690 were very low for all the regions of the LBW weldment as compared to that in the TIG weldment. The HAZ region of the LBW weldment showed the highest DOS value in any region of the weldment but even this value was quite low indicating absence of sensitization in LBW weldment. The attack along the grain boundaries for the weldments after EPR experiments were studied using optical and scanning electron microscopy.

  11. FlexyDos3D: a deformable anthropomorphic 3D radiation dosimeter: radiation properties

    NASA Astrophysics Data System (ADS)

    De Deene, Y.; Skyt, P. S.; Hil, R.; Booth, J. T.

    2015-02-01

    Three dimensional radiation dosimetry has received growing interest with the implementation of highly conformal radiotherapy treatments. The radiotherapy community faces new challenges with the commissioning of image guided and image gated radiotherapy treatments (IGRT) and deformable image registration software. A new three dimensional anthropomorphically shaped flexible dosimeter, further called ‘FlexyDos3D’, has been constructed and a new fast optical scanning method has been implemented that enables scanning of irregular shaped dosimeters. The FlexyDos3D phantom can be actuated and deformed during the actual treatment. FlexyDos3D offers the additional advantage that it is easy to fabricate, is non-toxic and can be molded in an arbitrary shape with high geometrical precision. The dosimeter formulation has been optimized in terms of dose sensitivity. The influence of the casting material and oxygen concentration has also been investigated. The radiophysical properties of this new dosimeter are discussed including stability, spatial integrity, temperature dependence of the dosimeter during radiation, readout and storage, dose rate dependence and tissue equivalence. The first authors Y De Deene and P S Skyt made an equivalent contribution to the experimental work presented in this paper.

  12. Theoretical proposal for a magnetic resonance study of charge transport in organic semiconductors

    NASA Astrophysics Data System (ADS)

    Mkhitaryan, Vagharsh

    Charge transport in disordered organic semiconductors occurs via carrier incoherent hops in a band of localized states. In the framework of continuous-time random walk the carrier on-site waiting time distribution (WTD) is one of the basic characteristics of diffusion. Besides, WTD is fundamentally related to the density of states (DOS) of localized states, which is a key feature of a material determining the optoelectric properties. However, reliable first-principle calculations of DOS in organic materials are not yet available and experimental characterization of DOS and WTD is desirable. We theoretically study the spin dynamics of hopping carriers and propose measurement schemes directly probing WTD, based on the zero-field spin relaxation and the primary (Hahn) spin echo. The proposed schemes are possible because, as we demonstrate, the long-time behavior of the zero-field relaxation and the primary echo is determined by WTD, both for the hyperfine coupling dominated and the spin-orbit coupling dominated spin dynamics. We also examine the dispersive charge transport, which is a non-Markovian sub-diffusive process characterized by non-stationarity. We show that the proposed schemes unambiguously capture the effects of non-stationarity, e.g., the aging behavior of random walks. This work was supported by the Department of Energy-Basic Energy Sciences under Contract No. DE-AC02-07CH11358.

  13. Feeding ecology of the lizard Tropidurus oreadicus Rodrigues 1987 (Tropiduridae) at Serra dos Carajás, Pará state, northern Brazil.

    PubMed

    Rocha, C F D; Siqueira, C C

    2008-02-01

    Tropidurus species commonly prey on arthropods, but they may also feed on vertebrates and plant material. The lizard Tropidurus oreadicus (Tropiduridae) is common in open vegetation habitats and generally has sexual dimorphism. In this study we analyzed the diet of T. oreadicus at Serra dos Carajás, Pará, in the north of Brazil. Snout-vent length (SVL) and jaw width (JW) were taken for 34 lizards. There was a significant difference in SVL and in JW, with males being larger than females. All lizards analyzed contained food in their stomachs. The diet of T. oreadicus at Serra dos Carajás was characterized by the consumption of a relative wide spectrum of food item categories (21 types of items), consisting of arthropods, part of one vertebrate and plant material, which characterizes the diet of a generalist predator. Volumetrically, the most important items in the diet of both sexes of T. oreadicus were flowers (M = 61.7%; F = 33%) and orthopterans (M = 1.7%; F = 3.5%). Ants were the most frequently consumed (100% for both sexes) and the most numerous (M = 94.5%; F = 89.4%) food item. Flowers also were frequently consumed (M = 91.7%; F = 54.5%), with their relative consumption differing significantly between sexes. There was not a significant sexual difference in prey volume, neither in number of preys per stomach, nor in type of prey ingested. There was no relationship between lizard jaw width and the mean volume of prey. The data showed that T. oreadicus is a relatively generalist lizard in terms of diet and that consumes large volumes of plant material, especially flowers of one species of genus Cassia.

  14. 50 CFR 600.240 - Security assurances.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... ADMINISTRATION, DEPARTMENT OF COMMERCE MAGNUSON-STEVENS ACT PROVISIONS Council Membership § 600.240 Security... meetings, materials classified for national security purposes, the agency or individual (e.g., DOS, USCG... classified for national security purposes, the agency or individual (e.g., Department of State, U.S. Coast...

  15. FIRST PRINCIPLES STUDY ON ELECTRONIC AND OPTICAL PROPERTIES OF Al-DOPED γ-Ge3N4

    NASA Astrophysics Data System (ADS)

    Ding, Y. C.; Xiang, A. P.; Zhu, X. H.; Luo, J.; Hu, X. F.

    2012-12-01

    First principles study of the structural, electronic and optical properties of Al-doped γ-Ge3N4 with different concentration has been reported using the pseudo-potential plane wave method within the generalized gradient approximation (GGA). The binding energy and the formation energy suggest that Aluminum (Al) impurities prefer to substitute Ge at octahedral sites. Different doping concentrations are considered and the corresponding density of states (DOS) are analyzed. Calculated DOS indicates that there are holes in the top of the valance band after doping, meaning a p-type doping. We study the complex dielectric function, the absorption coefficient, and the electron energy loss spectra. It is demonstrated that for the low Al concentration, the material exhibits the dielectric behavior and for the high Al concentration, the material has possibilities to exhibit some metallic behavior. The γ-Ge3N4 doped with Al has a much higher static dielectric constant than undoped γ-Ge3N4, implying its potential applications in electronics and optics.

  16. CARES/PC - CERAMICS ANALYSIS AND RELIABILITY EVALUATION OF STRUCTURES

    NASA Technical Reports Server (NTRS)

    Szatmary, S. A.

    1994-01-01

    The beneficial properties of structural ceramics include their high-temperature strength, light weight, hardness, and corrosion and oxidation resistance. For advanced heat engines, ceramics have demonstrated functional abilities at temperatures well beyond the operational limits of metals. This is offset by the fact that ceramic materials tend to be brittle. When a load is applied, their lack of significant plastic deformation causes the material to crack at microscopic flaws, destroying the component. CARES/PC performs statistical analysis of data obtained from the fracture of simple, uniaxial tensile or flexural specimens and estimates the Weibull and Batdorf material parameters from this data. CARES/PC is a subset of the program CARES (COSMIC program number LEW-15168) which calculates the fast-fracture reliability or failure probability of ceramic components utilizing the Batdorf and Weibull models to describe the effects of multi-axial stress states on material strength. CARES additionally requires that the ceramic structure be modeled by a finite element program such as MSC/NASTRAN or ANSYS. The more limited CARES/PC does not perform fast-fracture reliability estimation of components. CARES/PC estimates ceramic material properties from uniaxial tensile or from three- and four-point bend bar data. In general, the parameters are obtained from the fracture stresses of many specimens (30 or more are recommended) whose geometry and loading configurations are held constant. Parameter estimation can be performed for single or multiple failure modes by using the least-squares analysis or the maximum likelihood method. Kolmogorov-Smirnov and Anderson-Darling goodness-of-fit tests measure the accuracy of the hypothesis that the fracture data comes from a population with a distribution specified by the estimated Weibull parameters. Ninety-percent confidence intervals on the Weibull parameters and the unbiased value of the shape parameter for complete samples are provided when the maximum likelihood technique is used. CARES/PC is written and compiled with the Microsoft FORTRAN v5.0 compiler using the VAX FORTRAN extensions and dynamic array allocation supported by this compiler for the IBM/MS-DOS or OS/2 operating systems. The dynamic array allocation routines allow the user to match the number of fracture sets and test specimens to the memory available. Machine requirements include IBM PC compatibles with optional math coprocessor. Program output is designed to fit 80-column format printers. Executables for both DOS and OS/2 are provided. CARES/PC is distributed on one 5.25 inch 360K MS-DOS format diskette in compressed format. The expansion tool PKUNZIP.EXE is supplied on the diskette. CARES/PC was developed in 1990. IBM PC and OS/2 are trademarks of International Business Machines. MS-DOS and MS OS/2 are trademarks of Microsoft Corporation. VAX is a trademark of Digital Equipment Corporation.

  17. Quality control and assurance for validation of DOS/I measurements

    NASA Astrophysics Data System (ADS)

    Cerussi, Albert; Durkin, Amanda; Kwong, Richard; Quang, Timothy; Hill, Brian; Tromberg, Bruce J.; MacKinnon, Nick; Mantulin, William W.

    2010-02-01

    Ongoing multi-center clinical trials are crucial for Biophotonics to gain acceptance in medical imaging. In these trials, quality control (QC) and assurance (QA) are key to success and provide "data insurance". Quality control and assurance deal with standardization, validation, and compliance of procedures, materials and instrumentation. Specifically, QC/QA involves systematic assessment of testing materials, instrumentation performance, standard operating procedures, data logging, analysis, and reporting. QC and QA are important for FDA accreditation and acceptance by the clinical community. Our Biophotonics research in the Network for Translational Research in Optical Imaging (NTROI) program for breast cancer characterization focuses on QA/QC issues primarily related to the broadband Diffuse Optical Spectroscopy and Imaging (DOS/I) instrumentation, because this is an emerging technology with limited standardized QC/QA in place. In the multi-center trial environment, we implement QA/QC procedures: 1. Standardize and validate calibration standards and procedures. (DOS/I technology requires both frequency domain and spectral calibration procedures using tissue simulating phantoms and reflectance standards, respectively.) 2. Standardize and validate data acquisition, processing and visualization (optimize instrument software-EZDOS; centralize data processing) 3. Monitor, catalog and maintain instrument performance (document performance; modularize maintenance; integrate new technology) 4. Standardize and coordinate trial data entry (from individual sites) into centralized database 5. Monitor, audit and communicate all research procedures (database, teleconferences, training sessions) between participants ensuring "calibration". This manuscript describes our ongoing efforts, successes and challenges implementing these strategies.

  18. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cochran, J.R.; Danneels, J.; Kenagy, W.D.

    The Al Tuwaitha nuclear complex near Baghdad contains a significant number of nuclear facilities from Saddam Hussein's dictatorship. Because of past military operations, lack of upkeep and looting there is now an enormous radioactive waste problem at Al Tuwaitha. Al Tuwaitha contains uncharacterised radioactive wastes, yellow cake, sealed radioactive sources, and contaminated metals. The current security situation in Iraq hampers all aspects of radioactive waste management. Further, Iraq has never had a radioactive waste disposal facility, which means that ever increasing quantities of radioactive waste and material must be held in guarded storage. The Iraq Nuclear Facility Dismantlement and Disposalmore » Program (the NDs Program) has been initiated by the U.S. Department of State (DOS) to assist the Government of Iraq (GOI) in eliminating the threats from poorly controlled radioactive materials, while building human capacities so that the GOI can manage other environmental cleanups in their country. The DOS has funded the International Atomic Energy Agency (IAEA) to provide technical assistance to the GOI via a Technical Cooperation Project. Program coordination will be provided by the DOS, consistent with U.S. and GOI policies, and Sandia National Laboratories will be responsible for coordination of participants and for providing waste management support. Texas Tech University will continue to provide in-country assistance, including radioactive waste characterization and the stand-up of the Iraq Nuclear Services Company. The GOI owns the problems in Iraq and will be responsible for the vast majority of the implementation of the NDs Program. (authors)« less

  19. Recent Literature Shows Accelerated Growth in Hypermedia Tools: An Annotated Bibliography.

    ERIC Educational Resources Information Center

    Gabbard, Ralph

    1994-01-01

    Presents an annotated bibliography of materials on hypertext/hypermedia. Information available on the World Wide Web is described; journals that cover hypermedia are listed; and the main bibliography is divided into 3 sections on general hypertext applications (17 titles), DOS/Windows applications (17 titles), and HyperCard applications (18…

  20. Ab-Initio Calculation of Electronic Structure of Lead Halide Perovskites with Formamidinium Cation as an Active Material for Perovskite Solar Cells

    NASA Astrophysics Data System (ADS)

    Indari, E. D.; Wungu, T. D. K.; Hidayat, R.

    2017-07-01

    Organic lead halide perovskite material based solar cells show impressive power conversion efficiencies, which can reach above 19 percent for perovskite solar cell with methyl-ammonium cations. These efficiencies are originated from efficient photoexcitation and charge carrier transport and not observed in conventional perovskite crystals. In this preliminary research work, we therefore performed Density Functional Theory (DFT) calculation of formamidinium lead iodide (FAPI), an alternative to methyl-ammonium lead iodide (MAPI), to predict their electronic structure and density of state (DOS). The calculation result at the most stable lattice parameters show a good agreement with the experiment results. The obtained band gap energy is 1.307 eV. The valence band is dominantly formed by the 5p orbitals of I- anions, while the conduction band is dominantly formed by the 6p orbitals of Pb2+ cations. The DOS of valence band of this perovskite seems smaller compared to the case of methyl-ammonium lead iodide perovskite, which then may explain the observation of smaller power conversion efficiencies in perovskite solar cells with this formamidinium cations.

  1. Metallicity of Ca 2Cu 6P 5 with single and double copper-pnictide layers

    DOE PAGES

    Li, Li; Parker, David; Chi, Miaofang; ...

    2016-02-16

    We report thermodynamic and transport properties, and also theoretical calculations, for Cu-based compound Ca 2Cu 6P 5 and compare with CaCu 2-δP 2. Both materials have layers of edge-sharing copper pnictide tetrahedral CuP 4, similar to Fe–As and Fe–Se layers (with FeAs 4, FeSe 4) in the iron-based superconductors. Despite the presence of this similar transition-metal pnictide layer, we find that both Ca 2Cu 6P 5 and CaCu 2-δP 2 have temperature-independent magnetic susceptibility and show metallic behavior with no evidence of either magnetic ordering or superconductivity down to 1.8 K CaCu 2-δP 2 is slightly off-stoichiometric, with δ =more » 0.14. Theoretical calculations suggest that unlike Fe 3d-based magnetic materials with a large density of states (DOS) at the Fermi surface, Cu have comparatively low DOS, with the majority of the 3d spectral weight located well below Fermi level. The room-temperature resistivity value of Ca 2Cu 6P 5 is only 9 μΩ-cm, due to a substantial plasma frequency and an inferred electron-phonon coupling λ of 0.073 (significantly smaller than that of metallic Cu). Also, microscopy result shows that Cu–Cu distance along the c-axis within the double layers can be very short (2.5 Å), even shorter than metallic elemental copper bond (2.56 Å). The value of dρ/dT for CaCu 2-δP 2 at 300 K is approximately three times larger than in Ca 2Cu 6P 5, which suggests the likelihood of stronger electron-phonon coupling. Lastly, this study shows that the details of Cu–P layers and bonding are important for their transport characteristics. In addition, it emphasizes the remarkable character of the DOS of ‘122’ iron-based materials, despite much structural similarities.« less

  2. Anharmonic phonons and magnons in BiFeO3

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Delaire, Olivier A; Ma, Jie; Stone, Matthew B

    2012-01-01

    The phonon density of states (DOS) and magnetic excitation spectrum of polycrystalline BiFeO3 were measured for temperatures 200 < T < 750K , using inelastic neutron scattering (INS). Our results indicate that the magnetic spectrum of BiFeO3 closely resembles that of similar Fe perovskites, such as LaFeO3, despite the cycloid modulation in BiFeO3. We do not find any evidence for a spin gap. A strong T-dependence of the phonon DOS was found, with a marked broadening of the whole spectrum, providing evidence of strong anharmonicity. This anharmonicity is corroborated by large amplitude motions of Bi and O ions observed withmore » neutron diffraction. These results highlight the importance of spin-phonon coupling in this material.« less

  3. Software To Go: A Catalog of Software Available for Loan.

    ERIC Educational Resources Information Center

    Kurlychek, Ken, Comp.

    This catalog lists the holdings of the Software To Go software lending library and clearinghouse for programs and agencies serving students or clients who are deaf or hard of hearing. An introduction describes the clearinghouse and its collection of software, much of it commercial and copyrighted material, for Apple, Macintosh, and IBM (MS-DOS)…

  4. Dos Puertorriquenos Visitan Puerto Rico (Two Puerto Ricans Visit Puerto Rico).

    ERIC Educational Resources Information Center

    Tuttle, Harry Grover

    These materials for Spanish instruction are based on the meeting and friendship of two Puerto Ricans arriving in Puerto Rico for visits to their hometowns, their discussions of Puerto Rican life, and a sightseeing tour of San Juan. Introductory passages to the visitors' dialogues are in English, and dialogues are in Spanish, with photographs,…

  5. Unidad: Las influencias culturales en el arte mexicana (Unit: Cultural Influences in Mexican Art). Dos semanas.

    ERIC Educational Resources Information Center

    Finere, Neal

    This two-week unit, appropriate for bilingual education settings as well as foreign language programs, deals with the three primary cultural influences found in Mexican contemporary art. The multisensory materials, pragmatic focus, and direct creative student involvement are designed to make it a microcosmic, real-life experience. The first part…

  6. High thermoelectric power factor in two-dimensional crystals of Mo S2

    NASA Astrophysics Data System (ADS)

    Hippalgaonkar, Kedar; Wang, Ying; Ye, Yu; Qiu, Diana Y.; Zhu, Hanyu; Wang, Yuan; Moore, Joel; Louie, Steven G.; Zhang, Xiang

    2017-03-01

    The quest for high-efficiency heat-to-electricity conversion has been one of the major driving forces toward renewable energy production for the future. Efficient thermoelectric devices require high voltage generation from a temperature gradient and a large electrical conductivity while maintaining a low thermal conductivity. For a given thermal conductivity and temperature, the thermoelectric power factor is determined by the electronic structure of the material. Low dimensionality (1D and 2D) opens new routes to a high power factor due to the unique density of states (DOS) of confined electrons and holes. The 2D transition metal dichalcogenide (TMDC) semiconductors represent a new class of thermoelectric materials not only due to such confinement effects but especially due to their large effective masses and valley degeneracies. Here, we report a power factor of Mo S2 as large as 8.5 mW m-1K-2 at room temperature, which is among the highest measured in traditional, gapped thermoelectric materials. To obtain these high power factors, we perform thermoelectric measurements on few-layer Mo S2 in the metallic regime, which allows us to access the 2D DOS near the conduction band edge and exploit the effect of 2D confinement on electron scattering rates, resulting in a large Seebeck coefficient. The demonstrated high, electronically modulated power factor in 2D TMDCs holds promise for efficient thermoelectric energy conversion.

  7. Evaluation of the field-effect carrier mobility in single-grain (and polycrystalline) organic semconductors

    NASA Astrophysics Data System (ADS)

    Kwok, H. L.

    2005-08-01

    Mobility in single-grain and polycrystalline organic field-effect transistors (OFETs) is of interest because it affects the performance of these devices. While reasonable values of the hole mobility has been measured in pentacene OFETs, relatively speaking, our understanding of the detailed transport mechanisms is somewhat weak and there is a lack of precise knowledge on the effects of the materials parameters such as the site spacing, the localization length, the rms width of the density of states (DOS), the escape frequency, etc. This work attempts to analyze the materials parameters of pentacene OFETs extracted from data reported in the literature. In this work, we developed a model for the mobility parameter from first principle and extracted the relevant materials parameters. According to our analyses, the transport mechanisms in the OFETs are fairly complex and the electrical properties are dominated by the properties of the trap states. As observed, the single-grain OFETs having smaller values of the rms widths of the DOS (in comparison with the polycrystalline OFETs) also had higher hole mobilities. Our results showed that increasing the gate bias could have a similar but smaller effect. Potentially, increasing the escape frequency is a more effective way to raise the hole mobility and this parameter appears to be affected by changes in the molecular structure and in the degree of "disorder".

  8. Electronic properties and surface reactivity of SrO-terminated SrTiO3 and SrO-terminated iron-doped SrTiO3

    PubMed Central

    Staykov, Aleksandar; Tellez, Helena; Druce, John; Wu, Ji; Ishihara, Tatsumi; Kilner, John

    2018-01-01

    Abstract Surface reactivity and near-surface electronic properties of SrO-terminated SrTiO3 and iron doped SrTiO3 were studied with first principle methods. We have investigated the density of states (DOS) of bulk SrTiO3 and compared it to DOS of iron-doped SrTiO3 with different oxidation states of iron corresponding to varying oxygen vacancy content within the bulk material. The obtained bulk DOS was compared to near-surface DOS, i.e. surface states, for both SrO-terminated surface of SrTiO3 and iron-doped SrTiO3. Electron density plots and electron density distribution through the entire slab models were investigated in order to understand the origin of surface electrons that can participate in oxygen reduction reaction. Furthermore, we have compared oxygen reduction reactions at elevated temperatures for SrO surfaces with and without oxygen vacancies. Our calculations demonstrate that the conduction band, which is formed mainly by the d-states of Ti, and Fe-induced states within the band gap of SrTiO3, are accessible only on TiO2 terminated SrTiO3 surface while the SrO-terminated surface introduces a tunneling barrier for the electrons populating the conductance band. First principle molecular dynamics demonstrated that at elevated temperatures the surface oxygen vacancies are essential for the oxygen reduction reaction. PMID:29535797

  9. Interannual variability of dust-mass loading and composition of dust deposited on snow cover in the San Juan Mountains, CO, USA: Insights into effects on snow melt

    NASA Astrophysics Data System (ADS)

    Goldstein, H. L.; Reynolds, R. L.; Derry, J.; Kokaly, R. F.; Moskowitz, B. M.

    2017-12-01

    Dust deposited on snow cover (DOS) in the American West can enhance snow-melt rates and advance the timing of melting, which together can result in earlier-than-normal runoff and overall smaller late-season water supplies. Understanding DOS properties and how they affect the absorption of solar radiation can lead to improved snow-melt models by accounting for important dust components. Here, we report on the interannual variability of DOS-mass loading, particle size, organic matter, and iron mineralogy, and their correspondences to laboratory-measured reflectance of samples from the Swamp Angel Study Plot in the San Juan Mountains, Colorado, USA. Samples were collected near the end of spring in water year 2009 (WY09) and from WY11-WY16, when dust layers deposited throughout the year had merged into one layer at the snow surface. Dust-mass loading on snow ranged 2-64 g/m2, mostly as particles with median sizes of 13-33 micrometers. Average reflectance values of DOS varied little across total (0.4 to 2.50 µm) and visible (0.4 to 0.7 µm) wavelengths at 0.30-0.45 and 0.19-0.27, respectively. Reflectance values lacked correspondence to particle-size. Total reflectance values inversely corresponded to concentrations of (1) organic matter content (4-20 weight %; r2 = 0.71) that included forms of black carbon and locally derived material such as pollen, and (2) magnetite (0.05 to 0.13 weight %; r2 = 0.44). Magnetite may be a surrogate for related dark, light-absorbing minerals. Concentrations of crystalline ferric oxide minerals (hematite+goethite) based on magnetic properties at room-temperature did not show inverse association to visible reflectance values. These ferric oxide measures, however, did not account for the amounts of nano-sized ferric oxides known to exist in these samples. Quantification of such nano-sized particles is required to evaluate their possible effects on visible reflectance. Nonetheless, our results emphasize that reflectance values of year-end DOS layers at this site do not appear to be highly sensitive to variations in some measured DOS properties. These preliminary results cannot be broadly applied to other DOS sites in the American West on the basis of previous and ongoing studies.

  10. Superconductivity in semimetallic B i 3 O 2 S 3

    DOE PAGES

    Li, L.; Parker, D.; Babkevich, P.; ...

    2015-03-12

    We report in this paper a further investigation on the thermodynamic and transport properties, and an assessment of theoretical calculations, for the BiS 2-layered Bi 3O 2S 3 superconductor. The polycrystalline sample is synthesized with a superconducting transition temperature of T c onset=5.75K and T c zero=4.03K (≈Tc mag) that drops to 3.3 K by applying a hydrostatic pressure of 6 kbar. Density-of-states (DOS) calculations give substantial hybridization between Bi, O, and S, with Bi the largest component of DOS, which supports the idea that the BiS 2 layer is relevant for producing electron-phonon coupling. An analysis of previously publishedmore » specific heat data for Bi 3O 2S 3 is additionally suggestive of a strong electron-phonon interaction in the Bi-O-S system. The analysis of the Seebeck coefficient results strongly suggests that Bi 3O 2S 3 is a semimetal. In fact, we found the semimetallic or narrow band gap behavior may occur in certain other materials in the BiS 2-layered class of materials, such as Bi 4O 4S 3.« less

  11. Comparative study on degradation and trap density-of-states of p type and n type organic semiconductors

    NASA Astrophysics Data System (ADS)

    Shijeesh, M. R.; Vikas, L. S.; Jayaraj, M. K.; Puigdollers, J.

    2014-10-01

    The OTFTs with both p type and n type channel layers were fabricated using the inverted-staggered (top contact) structure by thermal vapour deposition on Si/SiO2 substrate. Pentacene and N,N'-Dioctyl- 3,4,9,10- perylenedicarboximide (PTCDI-C8) were used as channel layer for the fabrications of p type and n type OTFTs respectively. A comparative study on the degradation and density of states (DOS) of p type and n type organic semiconductors have been carried out. In order to compare the stability and degradation of pentacene and PTCDI-C8 OTFTs, the devices were exposed to air for 2 h before performing electrical measurements in air. The DOS measurements revealed that a level with defect density of 1020 cm-3 was formed only in PTCDI C8 layer on exposure to air. The oxygen adsorption into the PTCDI-C8 active layer can be attributed to the formation of this level at 0.15 eV above the LUMO level. The electrical charge transport is strongly affected by the oxygen traps and hence n type organic materials are less stable than p type organic materials.

  12. NMR study of B-2p Fermi-level density of states in the transition metal diborides

    NASA Astrophysics Data System (ADS)

    Lue, C. S.; Lai, W. J.

    2005-04-01

    We present a systematic study of the AlB2-type transition metal diborides by measuring the 11B NMR spin-lattice relaxation rate on TiB2, VB2, ZrB2, NbB2, HfB2, as well as TaB2. For all studied materials, the observed relaxation at B nuclei is mainly due to the p-electrons. The comparison with theoretical calculations allows the experimental determination of the partial B-2p Fermi-level density of states (DOS). In addition, the extracted B-2p Fermi-level DOS values in TiB2, ZrB2, and HfB are consistently smaller than in VB2, NbB2, and TaB2. We connect this trend to the rigid-band scenario raised by band structure calculations.

  13. Electrochemical impedance spectroscopy for study of electronic structure in disordered organic semiconductors—Possibilities and limitations

    NASA Astrophysics Data System (ADS)

    Schauer, F.; Nádaždy, V.; Gmucová, K.

    2018-04-01

    There is potential in applying conjugated polymers in novel organic optoelectronic devices, where a comprehensive understanding of the fundamental processes and energetics involved during transport and recombination is still lacking, limiting further device optimization. The electronic transport modeling and its optimization need the energy distribution of transport and defect states, expressed by the energy distribution of the Density of States (DOS) function, as input/comparative parameters. We present the Energy Resolved-Electrochemical Impedance Spectroscopy (ER-EIS) method for the study of transport and defect electronic states in organic materials. The method allows mapping over unprecedentedly wide energy and DOS ranges. The ER-EIS spectroscopic method is based on the small signal interaction between the surface of the organic film and the liquid electrolyte containing reduction-oxidation (redox) species, which is similar to the extraction of an electron by an acceptor and capture of an electron by a donor at a semiconductor surface. The desired DOS of electronic transport and defect states can be derived directly from the measured redox response signal to the small voltage perturbation at the instantaneous position of the Fermi energy, given by the externally applied voltage. The theory of the ER-EIS method and conditions for its validity for solid polymers are presented in detail. We choose four case studies on poly(3-hexylthiophene-2,5-diyl) and poly[methyl(phenyl)silane] to show the possibilities of the method to investigate the electronic structure expressed by DOS of polymers with a high resolution of about 6 orders of magnitude and in a wide energy range of 6 eV.

  14. Ab-initio atomic level stress and role of d-orbitals in CuZr, CuZn and CuY

    NASA Astrophysics Data System (ADS)

    Ojha, Madhusudan; Nicholson, Don M.; Egami, Takeshi

    2015-03-01

    Atomic level stress offers a new tool to characterize materials within the local approximation to density functional theory (DFT). Ab-initio atomic level stresses in B2 structures of CuZr, CuZn and CuY are calculated and results are explained on the basis of d-orbital contributions to Density of States (DOS). The overlap of d-orbital DOS plays an important role in the relative magnitude of atomic level stresses in these structures. The trends in atomic level stresses that we observed in these simple B2 structures are also seen in complex structures such as liquids, glasses and solid solutions. The stresses are however modified by the different coordination and relaxed separation distances in these complex structures. We used the Locally Self-Consistent Multiple Scattering (LSMS) code and Vienna Ab-initio Simulation Package (VASP) for ab-initio calculations.

  15. Universal spectral signatures in pnictides and cuprates: the role of quasiparticle-pair coupling.

    PubMed

    Sacks, William; Mauger, Alain; Noat, Yves

    2017-11-08

    Understanding the physical properties of a large variety of high-T c superconductors (SC), the cuprate family as well as the more recent iron-based superconductors, is still a major challenge. In particular, these materials exhibit the 'peak-dip-hump' structure in the quasiparticle density of states (DOS). The origin of this structure is explained within our pair-pair interaction (PPI) model: The non-superconducting state consists of incoherent pairs, a 'Cooper-pair glass' which, due to the PPI, undergoes a Bose-like condensation below T c to the coherent SC state. We derive the equations of motion for the quasiparticle operators showing that the DOS 'peak-dip-hump' is caused by the coupling between quasiparticles and excited pair states, or 'super-quasiparticles'. The renormalized SC gap function becomes energy-dependent and non retarded, reproducing accurately the experimental spectra of both pnictides and cuprates, despite the large difference in gap value.

  16. En Busqueda de la Escuela del Siglo XXI: Dos Experiencias de Autoaprendizaje (In Search of the 21st Century School: Two Self-Learning Experiences).

    ERIC Educational Resources Information Center

    Schiefelbein, Ernesto; And Others

    This book is a contribution to the dialogue that is maintained today around the problems of education. The book contains four parts: (1) "In Search of the 21st Century School. Can the Colombian New School (EN) Show Us the Way?"; (2) "Experimentation with Self-Learning Materials in Two Schools in Conchali (Chile)"; (3)…

  17. Anderson localization of electrons in single crystals: LixFe7Se8

    PubMed Central

    Ying, Tianping; Gu, Yueqiang; Chen, Xiao; Wang, Xinbo; Jin, Shifeng; Zhao, Linlin; Zhang, Wei; Chen, Xiaolong

    2016-01-01

    Anderson (disorder-induced) localization, proposed more than half a century ago, has inspired numerous efforts to explore the absence of wave diffusions in disordered media. However, the proposed disorder-induced metal-insulator transition (MIT), associated with the nonpropagative electron waves, has hardly been observed in three-dimensional (3D) crystalline materials, let alone single crystals. We report the observation of an MIT in centimeter-size single crystals of LixFe7Se8 induced by lattice disorder. Both specific heat and infrared reflectance measurements reveal the presence of considerable electronic states in the vicinity of the Fermi level when the MIT occurs, suggesting that the transition is not due to Coulomb repulsion mechanism. The 3D variable range hopping regime evidenced by electrical transport measurements at low temperatures indicates the localized nature of the electronic states on the Fermi level. Quantitative analyses of carrier concentration, carrier mobility, and simulated density of states (DOS) fully support that LixFe7Se8 is an Anderson insulator. On the basis of these results, we provide a unified DOS picture to explain all the experimental results, and a schematic diagram for finding other potential Anderson insulators. This material will thus serve as a rich playground for both theoretical and experimental investigations on MITs and disorder-induced phenomena. PMID:26989781

  18. XANES study of hydrogen incorporation in a Pd-capped Nb thin film

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ruckman, M.W.; Reisfeld, G.; Jisrawi, N.M.

    X-ray absorption near-edge structure (XANES) measurements were used to probe the H-charging-induced electronic structure changes of a 2400 {Angstrom} Nb film capped with Pd. These results are discussed in terms of {ital ab initio} linear augmented plane-wave (LAPW) band-structure calculations for this material. The Pd-L{sub 3}-edge XANES clearly manifested the spectral (Pd-d state related) changes expected for Pd-hydride formation, a white line feature degradation, and the appearance of a Pd-H antibonding feature at 6 eV above the threshold. The Nb-L{sub 2,3} edge changes with H charging show a distinct enhancement of the white line strength; a feature 6 eV abovemore » the edges, associated with Nb-H antibonding states in analogy with the Pd results; the suppression of a threshold-onset feature of Nb metal; and a shift of the centrum of the white line feature towards the threshold. Comparison of the Nb sphere projection of the d{sub 3/2} component of the LAPW density of states (DOS) to the Nb-L{sub 2}-edge spectra yields good basic agreement with the observed spectral changes. In particular, the substantial theoretical reduction in the DOS at, and just above, the Fermi energy (E{sub f}) is directly related to the near threshold Nb-L{sub 2,3} spectral changes. The more modest white line enhancement in the theoretical DOS is noted and discussed. Nb-K-edge XANES are also discussed in terms of the Nb-site p-state projected LAPW DOS. This last comparison indicates a p-state reduction near E{sub f} upon H charging of the Nb. {copyright} {ital 1998} {ital The American Physical Society}« less

  19. A bone tissue engineering strategy based on starch scaffolds and bone marrow cells cultured in a flow perfusion bioreactor

    NASA Astrophysics Data System (ADS)

    Gomes, Maria Manuela Estima

    A Engenharia de Tecidos e uma area cientifica em continua expansao. Os desenvolvimentos conseguidos por esta area tem contribuido significativamente para diversos avancos no campo da Medicina Regenerativa. Esta ciencia interdisciplinar combina os conhecimentos de diversas outras areas, tao distintas como a Engenharia de Materiais e a Biologia, com o objectivo de desenvolver substitutos sinteticos para tecidos humanos. Para se atingir este objectivo utilizam-se, de uma forma generica, combinacoes especificas de celulas e de um material de suporte tridimensional com propriedades adequadas, gerando um material hibrido cujas caracteristicas podem ainda ser moduladas atraves do sistema de cultura usado. A presente tese e centrada no desenvolvimento de estrategias de engenharia de tecido osseo baseadas na cultura in vitro de celulas previamente "semeadas" num suporte tridimensional ("scaffold"). Esta estrategia permite que as celulas adiram ao suporte, proliferem e segreguem matriz extracelular especifica do tecido osseo, ate se obter um substituto artificial funcional com caracteristicas do tecido original, que pode finalmente ser transplantado para tratar o defeito em causa. Para que uma estrategia deste tipo seja bem sucedida, pelo menos tres componentes fundamentais devem ser cuidadosamente estudados: o material de suporte (scaffold), as celulas a usar e o sistema de cultura in vitro. Dai que os principais objectivos desta tese estejam relacionados com estes tres aspectos, nomeadamente: • Desenvolvimento de scaffolds biodegradaveis a partir de polimeros a base de amido de milho que induzam a adesao e proliferacao celular e que apresentem propriedades adequadas, tais como a porosidade e interconectividade entre poros, de forma a proporcionar um ambiente que favoreca o desenvolvimento in vitro de um material hibrido com caracteristicas similares ao osso humano. • Estudo da utilizacao de celulas da medula ossea como uma potencial fonte de celulas para engenharia do tecido osseo, uma vez que estas celulas podem ser facilmente recolhidas do proprio paciente a tratar por metodos nao-invasivos (bioppsia) e em quantidades suficientes. Alem disso, tratando-se de uma fonte de celulas autologas (obtidas do proprio paciente) permitem evitar os riscos de transmissao de doencas contagiosas e/ou de rejeicao pelo sistema imunologico. • Estudo da influencia das condicoes de cultura in vitro geradas por um bioreactor de perfusao (em comparacao com os metodos tradicionais de cultura em condicoes estaticas) no desenvolvimento dos materiais hibridos, compostos pelas celulas e scaffolds, assim como as interaccoes do ambiente proporcionado por este sistema de cultura com as diferentes estruturas/arquitecturas e porosidades dos scaffolds utilizados. Estes objectivos convergem para o objectivo geral desta tese que consistiu no desenvolvimento de uma terapia de engenharia do tecido osseo alternativa as existentes e com potencial para vir a ser posteriormente utilizada na pratica clinica. Este objectivo foi avaliado atraves do estudo da funcionalidade dos materiais hibridos obtidos em diferentes condicoes de cultura in vitro (e utilizando diferentes scaffolds), partindo do principio que o sistema de perfusao poderia eventualmente superar as limitacoes de difusao tipicas dos sistema de cultura estatica e simultaneamente proporcionar estimulos mecânicos as celulas, semelhantes aos encontrados em condicoes fisiologicas. (Abstract shortened by ProQuest.).

  20. [Evaluation of four dark object atmospheric correction methods based on ZY-3 CCD data].

    PubMed

    Guo, Hong; Gu, Xing-fa; Xie, Yong; Yu, Tao; Gao, Hai-liang; Wei, Xiang-qin; Liu, Qi-yue

    2014-08-01

    The present paper performed the evaluation of four dark-object subtraction(DOS) atmospheric correction methods based on 2012 Inner Mongolia experimental data The authors analyzed the impacts of key parameters of four DOS methods when they were applied to ZY-3 CCD data The results showed that (1) All four DOS methods have significant atmospheric correction effect at band 1, 2 and 3. But as for band 4, the atmospheric correction effect of DOS4 is the best while DOS2 is the worst; both DOS1 and DOS3 has no obvious atmospheric correction effect. (2) The relative error (RE) of DOS1 atmospheric correction method is larger than 10% at four bands; The atmospheric correction effect of DOS2 works the best at band 1(AE (absolute error)=0.0019 and RE=4.32%) and the worst error appears at band 4(AE=0.0464 and RE=19.12%); The RE of DOS3 is about 10% for all bands. (3) The AE of atmospheric correction results for DOS4 method is less than 0. 02 and the RE is less than 10% for all bands. Therefore, the DOS4 method provides the best accuracy of atmospheric correction results for ZY-3 image.

  1. FASTRAN II - FATIGUE CRACK GROWTH STRUCTURAL ANALYSIS (UNIX VERSION)

    NASA Technical Reports Server (NTRS)

    Newman, J. C.

    1994-01-01

    Predictions of fatigue crack growth behavior can be made with the Fatigue Crack Growth Structural Analysis (FASTRAN II) computer program. As cyclic loads are applied to a selected crack configuration with an initial crack size, FASTRAN II predicts crack growth as a function of cyclic load history until either a desired crack size is reached or failure occurs. FASTRAN II is based on plasticity-induced crack-closure behavior of cracks in metallic materials and accounts for load-interaction effects, such as retardation and acceleration, under variable-amplitude loading. The closure model is based on the Dugdale model with modifications to allow plastically deformed material to be left along the crack surfaces as the crack grows. Plane stress and plane strain conditions, as well as conditions between these two, can be simulated in FASTRAN II by using a constraint factor on tensile yielding at the crack front to approximately account for three-dimensional stress states. FASTRAN II contains seventeen predefined crack configurations (standard laboratory fatigue crack growth rate specimens and many common crack configurations found in structures); and the user can define one additional crack configuration. The baseline crack growth rate properties (effective stress-intensity factor against crack growth rate) may be given in either equation or tabular form. For three-dimensional crack configurations, such as surface cracks or corner cracks at holes or notches, the fatigue crack growth rate properties may be different in the crack depth and crack length directions. Final failure of the cracked structure can be modelled with fracture toughness properties using either linear-elastic fracture mechanics (brittle materials), a two-parameter fracture criterion (brittle to ductile materials), or plastic collapse (extremely ductile materials). The crack configurations in FASTRAN II can be subjected to either constant-amplitude, variable-amplitude or spectrum loading. The applied loads may be either tensile or compressive. Several standardized aircraft flight-load histories, such as TWIST, Mini-TWIST, FALSTAFF, Inverted FALSTAFF, Felix and Gaussian, are included as options. FASTRAN II also includes two other methods that will help the user input spectrum load histories. The two methods are: (1) a list of stress points, and (2) a flight-by-flight history of stress points. Examples are provided in the user manual. Developed as a research program, FASTRAN II has successfully predicted crack growth in many metallic materials under various aircraft spectrum loading. A computer program DKEFF which is a part of the FASTRAN II package was also developed to analyze crack growth rate data from laboratory specimens to obtain the effective stress-intensity factor against crack growth rate relations used in FASTRAN II. FASTRAN II is written in standard FORTRAN 77. It has been successfully compiled and implemented on Sun4 series computers running SunOS and on IBM PC compatibles running MS-DOS using the Lahey F77L FORTRAN compiler. Sample input and output data are included with the FASTRAN II package. The UNIX version requires 660K of RAM for execution. The standard distribution medium for the UNIX version (LAR-14865) is a .25 inch streaming magnetic tape cartridge in UNIX tar format. It is also available on a 3.5 inch diskette in UNIX tar format. The standard distribution medium for the MS-DOS version (LAR-14944) is a 5.25 inch 360K MS-DOS format diskette. The contents of the diskette are compressed using the PKWARE archiving tools. The utility to unarchive the files, PKUNZIP.EXE, is included. The program was developed in 1984 and revised in 1992. Sun4 and SunOS are trademarks of Sun Microsystems, Inc. IBM PC is a trademark of International Business Machines Corp. MS-DOS is a trademark of Microsoft, Inc. F77L is a trademark of the Lahey Computer Systems, Inc. UNIX is a registered trademark of AT&T Bell Laboratories. PKWARE and PKUNZIP are trademarks of PKWare, Inc.

  2. FASTRAN II - FATIGUE CRACK GROWTH STRUCTURAL ANALYSIS (IBM PC VERSION)

    NASA Technical Reports Server (NTRS)

    Newman, J. C.

    1994-01-01

    Predictions of fatigue crack growth behavior can be made with the Fatigue Crack Growth Structural Analysis (FASTRAN II) computer program. As cyclic loads are applied to a selected crack configuration with an initial crack size, FASTRAN II predicts crack growth as a function of cyclic load history until either a desired crack size is reached or failure occurs. FASTRAN II is based on plasticity-induced crack-closure behavior of cracks in metallic materials and accounts for load-interaction effects, such as retardation and acceleration, under variable-amplitude loading. The closure model is based on the Dugdale model with modifications to allow plastically deformed material to be left along the crack surfaces as the crack grows. Plane stress and plane strain conditions, as well as conditions between these two, can be simulated in FASTRAN II by using a constraint factor on tensile yielding at the crack front to approximately account for three-dimensional stress states. FASTRAN II contains seventeen predefined crack configurations (standard laboratory fatigue crack growth rate specimens and many common crack configurations found in structures); and the user can define one additional crack configuration. The baseline crack growth rate properties (effective stress-intensity factor against crack growth rate) may be given in either equation or tabular form. For three-dimensional crack configurations, such as surface cracks or corner cracks at holes or notches, the fatigue crack growth rate properties may be different in the crack depth and crack length directions. Final failure of the cracked structure can be modelled with fracture toughness properties using either linear-elastic fracture mechanics (brittle materials), a two-parameter fracture criterion (brittle to ductile materials), or plastic collapse (extremely ductile materials). The crack configurations in FASTRAN II can be subjected to either constant-amplitude, variable-amplitude or spectrum loading. The applied loads may be either tensile or compressive. Several standardized aircraft flight-load histories, such as TWIST, Mini-TWIST, FALSTAFF, Inverted FALSTAFF, Felix and Gaussian, are included as options. FASTRAN II also includes two other methods that will help the user input spectrum load histories. The two methods are: (1) a list of stress points, and (2) a flight-by-flight history of stress points. Examples are provided in the user manual. Developed as a research program, FASTRAN II has successfully predicted crack growth in many metallic materials under various aircraft spectrum loading. A computer program DKEFF which is a part of the FASTRAN II package was also developed to analyze crack growth rate data from laboratory specimens to obtain the effective stress-intensity factor against crack growth rate relations used in FASTRAN II. FASTRAN II is written in standard FORTRAN 77. It has been successfully compiled and implemented on Sun4 series computers running SunOS and on IBM PC compatibles running MS-DOS using the Lahey F77L FORTRAN compiler. Sample input and output data are included with the FASTRAN II package. The UNIX version requires 660K of RAM for execution. The standard distribution medium for the UNIX version (LAR-14865) is a .25 inch streaming magnetic tape cartridge in UNIX tar format. It is also available on a 3.5 inch diskette in UNIX tar format. The standard distribution medium for the MS-DOS version (LAR-14944) is a 5.25 inch 360K MS-DOS format diskette. The contents of the diskette are compressed using the PKWARE archiving tools. The utility to unarchive the files, PKUNZIP.EXE, is included. The program was developed in 1984 and revised in 1992. Sun4 and SunOS are trademarks of Sun Microsystems, Inc. IBM PC is a trademark of International Business Machines Corp. MS-DOS is a trademark of Microsoft, Inc. F77L is a trademark of the Lahey Computer Systems, Inc. UNIX is a registered trademark of AT&T Bell Laboratories. PKWARE and PKUNZIP are trademarks of PKWare, Inc.

  3. Cost of nursing most frequent procedures performed on severely burned patients.

    PubMed

    Melo, Talita de Oliveira; Lima, Antônio Fernandes Costa

    2017-01-01

    to identify the mean direct cost (MDC) of the most frequent procedures performed by nursing professionals on severely burned patients in an Intensive Care Unit. exploratory-descriptive quantitative single-case study. The MDC was calculated by multiplying time (timed) spent by nursing professionals in the performance of the procedures by the unit cost of direct labor, and adding the costs of material and medicine/solutions. a MDC of US$ 0.65 (SD=0.36) was obtained for "vital signs monitoring"; US$ 10.00 (SD=24.23) for "intravenous drug administration"; US$ 5.90 (SD=2.75) for "measurement of diuresis"; US$ 0.93 (SD=0.42) for "capillary blood glucose monitoring"; and US$ 99.75 (SD=129.55) for "bandaging". the knowledge developed can support managerial decision-making, contribute to the efficiency distribution of the resources involved and, when possible, provide cost-containment or cost-minimization strategies without impairing the quality of nursing care. identificar o custo direto médio (CDM) dos procedimentos realizados, com maior frequência, por profissionais de enfermagem, em uma Unidade de Terapia Intensiva, aos pacientes grandes queimados. pesquisa quantitativa, exploratório-descritiva, do tipo estudo de caso único. O CDM foi calculado multiplicando-se o tempo (cronometrado) despendido por profissionais de enfermagem na execução dos procedimentos, objeto de estudo, pelo custo unitário da mão de obra direta, somando-se ao custo dos materiais e soluções/medicamentos. obteve-se o CDM de US$ 0.65 (SD=0.36) para "controle dos sinais vitais"; US$ 10.00 (SD=24.23) para "administração de medicamentos via intravenosa"; US$ 5.90 (SD=2.75) para "mensuração de diurese"; US$ 0.93 (SD=0.42) para "verificação de glicemia capilar"; e US$ 99.75 (SD=129.55) para "curativo". o conhecimento desenvolvido pode fundamentar as tomadas de decisão gerenciais subsidiando a eficiência alocativa dos recursos envolvidos e, quando possível, indicar estratégias de contenção/minimização de custos sem prejuízos à qualidade da assistência de enfermagem.

  4. Tunneling study of SRF cavity-grade niobium.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Proslier, T.; Zasadzinski, J.; Cooley, L.

    Niobium, with its very high H{sub C1}, has been used in superconducting radio frequency (SRF) cavities for accelerator systems for 40 years with continual improvement. The quality factor of cavities (Q) is governed by the surface impedance R{sub BCS}, which depends on the quasiparticle gap, delta, and the superfluid density. Both of these parameters are seriously affected by surface imperfections (metallic phases, dissolved oxygen, magnetic impurities). Loss mechanism and surface treatments of Nb cavities found to improve the Q factor are still unsolved mysteries. We present here an overview of the capabilities of the point contact tunneling spectroscopy and Atomicmore » layer deposition methods and how they can help understanding the High field Q-drop and the mild baking effect. Tunneling spectroscopy was performed on Nb pieces from the same processed material used to fabricate SRF cavities. Air exposed, electropolished Nb exhibited a surface superconducting gap Delta = 1.55 meV, characteristic of clean, bulk Nb, however the tunneling density of states (DOS) was broadened significantly. Nb pieces treated with the same mild baking used to improve the Q-slope in SRF cavities revealed a much sharper DOS. Good fits to the DOS are obtained using Shiba theory suggesting that magnetic scattering of quasiparticles is the origin of the degraded surface superconductivity and the Q-slope problem of Nb SRF cavities.« less

  5. Ab initio study of gold-doped zigzag graphene nanoribbons

    NASA Astrophysics Data System (ADS)

    Srivastava, Pankaj; Dhar, Subhra; Jaiswal, Neeraj K.

    2014-12-01

    The electronic transport properties of zigzag graphene nanoribbons (ZGNRs) through covalent functionalization of gold (Au) atoms is investigated by using non-equilibrium Green's function combined with density functional theory. It is revealed that the electronic properties of Au-doped ZGNRs vary significantly due to spin and its non-inclusion. We find that the DOS profiles of Au-adsorbed ZGNR due to spin reveal very less number of states available for conduction, whereas non-inclusion of spin results in higher DOS across the Fermi level. Edge Au-doped ribbons exhibit stable structure and are energetically more favorable than the center Au-doped ZGNRs. Though the chemical interaction at the ZGNR-Au interface modifies the Fermi level, Au-adsorbed ZGNR reveals semimetallic properties. A prominent qualitative change of the I-V curve from linear to nonlinear is observed as the Au atom shifts from center toward the edges of the ribbon. Number of peaks present near the Fermi level ensures conductance channels available for charge transport in case of Au-center-substituted ZGNR. We predict semimetallic nature of the Au-adsorbed ZGNR with a high DOS peak distributed over a narrow energy region at the Fermi level and fewer conductance channels. Our calculations for the magnetic properties predict that Au functionalization leads to semiconducting nature with different band gaps for spin up and spin down. The outcomes are compared with the experimental and theoretical results available for other materials.

  6. Effect of doping on electronic properties of HgSe

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nag, Abhinav, E-mail: abhinavn76@gmail.com; Sastri, O. S. K. S., E-mail: sastri.osks@gmail.com; Kumar, Jagdish, E-mail: jagdishphysicist@gmail.com

    2016-05-23

    First principle study of electronic properties of pure and doped HgSe have been performed using all electron Full Potential Linearized Augmented Plane Wave (FP-LAPW) method using ELK code. The electronic exchange and co-relations are considered using Generalized Gradient Approach (GGA). Lattice parameter, Density of States (DOS) and Band structure calculations have been performed. The total energy curve (Energy vs Lattice parameter), DOS and band structure calculations are in good agreement with the experimental values and those obtained using other DFT codes. The doped material is studied within the Virtual Crystal Approximation (VCA) with doping levels of 10% to 25% ofmore » electrons (hole) per unit cell. Results predict zero band gap in undopedHgSe and bands meet at Fermi level near the symmetry point Γ. For doped HgSe, we found that by electron (hole) doping, the point where conduction and valence bands meet can be shifted below (above) the fermi level.« less

  7. Negative differential resistance in oxidized zigzag graphene nanoribbons.

    PubMed

    Wang, Min; Li, Chang Ming

    2011-01-28

    A theoretical study of zigzag graphene nanoribbons (ZGNRs) with an epoxy-pair chain (ZGO) is performed. The electronic transport properties are mainly evaluated by non-equilibrium Green's functions using the TRANSIESTA package. The results indicate that the graphene oxide can have a negative differential resistance (NDR) phenomenon, supported by bias-dependent transmission curves of different spin orientations. Applying non-zero bias voltages makes the density of states (DOS) of the right electrodes shift down. Due to an energy gap between the LUMO and LUMO+1 in ZGOs, with a certain bias, the conduction band of the right electrode cannot match the LUMO of the scattering region, then NDR occurs. With a larger bias, NDR ends when the second conduction band of the right electrode's DOS covers the LUMO of the scattering region. Since most of proposed ZGO systems possess such a gap between the LUMO and LUMO+1, NDR can be widely observed and this discovery may provide great potential applications in NDR-based nanoelectronics by using modified graphene materials.

  8. Valence Band Control of Metal Silicide Films via Stoichiometry.

    PubMed

    Streller, Frank; Qi, Yubo; Yang, Jing; Mangolini, Filippo; Rappe, Andrew M; Carpick, Robert W

    2016-07-07

    The unique electronic and mechanical properties of metal silicide films render them interesting for advanced materials in plasmonic devices, batteries, field-emitters, thermoelectric devices, transistors, and nanoelectromechanical switches. However, enabling their use requires precisely controlling their electronic structure. Using platinum silicide (PtxSi) as a model silicide, we demonstrate that the electronic structure of PtxSi thin films (1 ≤ x ≤ 3) can be tuned between metallic and semimetallic by changing the stoichiometry. Increasing the silicon content in PtxSi decreases the carrier density according to valence band X-ray photoelectron spectroscopy and theoretical density of states (DOS) calculations. Among all PtxSi phases, Pt3Si offers the highest DOS due to the modest shift of the Pt5d manifold away from the Fermi edge by only 0.5 eV compared to Pt, rendering it promising for applications. These results, demonstrating tunability of the electronic structure of thin metal silicide films, suggest that metal silicides can be designed to achieve application-specific electronic properties.

  9. Ab initio study of (Fe, Ni) doped GaAs: Magnetic, electronic properties and Faraday rotation

    NASA Astrophysics Data System (ADS)

    Sbai, Y.; Ait Raiss, A.; Bahmad, L.; Benyoussef, A.

    2017-06-01

    The interesting diluted magnetic semiconductor (DMS), Gallium Arsenide (GaAs), was doped with the transition metals magnetic impurities: iron (Fe) and Nickel (Ni), in one hand to study the magnetic and magneto-optical properties of the material Ga(Fe, Ni) As, in the other hand to investigate the effect of the doping on the properties of this material, the calculations were performed within the spin polarized density functional theory (DFT) and generalized gradient approximation (GGA) with AKAI KKR-CPA method, the density of states (DOS) for different doping concentrations were calculated, giving the electronical properties, as well as the magnetic state and magnetic states energy, also the effect of these magnetic impurities on the Faraday rotation as magneto-optical property. Furthermore, we found the stable magnetic state for our doped material GaAs.

  10. Self-regulating the effortful "social dos".

    PubMed

    Cortes, Kassandra; Kammrath, Lara K; Scholer, Abigail A; Peetz, Johanna

    2014-03-01

    In the current research, we explored differences in the self-regulation of the personal dos (i.e., engaging in active and effortful behaviors that benefit the self) and in the self-regulation of the social dos (engaging in those same effortful behaviors to benefit someone else). In 6 studies, we examined whether the same trait self-control abilities that predict task persistence on personal dos would also predict task persistence on social dos. That is, would the same behavior, such as persisting through a tedious and attentionally demanding task, show different associations with trait self-control when it is framed as benefitting the self versus someone else? In Studies 1-3, we directly compared the personal and social dos and found that trait self-control predicted self-reported and behavioral personal dos but not social dos, even when the behaviors were identical and when the incentives were matched. Instead, trait agreeableness--a trait linked to successful self-regulation within the social domain--predicted the social dos. Trait self-control did not predict the social dos even when task difficulty increased (Study 4), but it did predict the social don'ts, consistent with past research (Studies 5-6). The current studies provide support for the importance of distinguishing different domains of self-regulated behaviors and suggest that social dos can be successfully performed through routes other than traditional self-control abilities. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  11. DOS-32 System Manual

    DOT National Transportation Integrated Search

    1973-06-01

    This manual describes the internal workings of the Disk Operating System (DOS-32 for the Noneywell H - 632 computer. DOS - 32 is a core resident, one user, console oriented operating system written primarily in FORTRAN. A companion document DOS - 32 ...

  12. DOS-32 User's Manual

    DOT National Transportation Integrated Search

    1973-01-01

    This manual describes the internal workings of the Disk Operating System (DOS-32 for the Noneywell H - 632 computer. DOS - 32 is a core resident, one user, console oriented operating system written primarily in FORTRAN. A companion document DOS - 32 ...

  13. Discos de acresção em sistemas Be-X

    NASA Astrophysics Data System (ADS)

    Lopes de Oliveira, R.; Janot-Pacheco, E.

    2003-08-01

    Alguns fenômenos de outbursts em Be-X sugerem a existência, mesmo que temporária, de um disco de acresção quando da passagem do objeto compacto pelo periastro orbital. Neste trabalho avaliamos a possibilidade de formação do disco de acresção em sistemas Be+estrela de neutrons e Be+anã branca, e a influência da excentricidade orbital na ocorrência deste fenômeno. Utilizamos a expressão analítica para o momento angular específico da matéria constituinte de um meio em expansão lenta, como é o caso do disco circunstelar das estrelas Be, proposta por Wang(1981), sob a condição básica de que o raio de circularização deva ser maior do que o raio de Alfvén. Concluímos que existe um limite para o período orbital do sistema acima do qual não é possível a formação do disco de acresção, e que este valor aumenta para sistemas com excentricidade orbital maior.

  14. TRACER - TRACING AND CONTROL OF ENGINEERING REQUIREMENTS

    NASA Technical Reports Server (NTRS)

    Turner, P. R.

    1994-01-01

    TRACER (Tracing and Control of Engineering Requirements) is a database/word processing system created to document and maintain the order of both requirements and descriptive material associated with an engineering project. A set of hierarchical documents are normally generated for a project whereby the requirements of the higher level documents levy requirements on the same level or lower level documents. Traditionally, the requirements are handled almost entirely by manual paper methods. The problem with a typical paper system, however, is that requirements written and changed continuously in different areas lead to misunderstandings and noncompliance. The purpose of TRACER is to automate the capture, tracing, reviewing, and managing of requirements for an engineering project. The engineering project still requires communications, negotiations, interactions, and iterations among people and organizations, but TRACER promotes succinct and precise identification and treatment of real requirements separate from the descriptive prose in a document. TRACER permits the documentation of an engineering project's requirements and progress in a logical, controllable, traceable manner. TRACER's attributes include the presentation of current requirements and status from any linked computer terminal and the ability to differentiate headers and descriptive material from the requirements. Related requirements can be linked and traced. The program also enables portions of documents to be printed, individual approval and release of requirements, and the tracing of requirements down into the equipment specification. Requirement "links" can be made "pending" and invisible to others until the pending link is made "binding". Individuals affected by linked requirements can be notified of significant changes with acknowledgement of the changes required. An unlimited number of documents can be created for a project and an ASCII import feature permits existing documents to be incorporated. TRACER can automatically renumber section headers when inserting or deleting sections of a document and generate sign-off forms for any approval process as well as a table of contents. TRACER was implemented on an IBM PC under PC-DOS. The program requires 640K RAM, a hard disk, and PC-DOS version 3.3 or higher. It was written in CLIPPER (Summer '87). TRACER is available on two 5.25 inch 1.2Mb MS-DOS format diskettes. The executable program is also provided with the distribution. TRACER is a copyrighted work with all copyright vested in the National Aeronautics and Space Administration. IBM PC and PC-DOS are registered trademarks of International Business Machines. CLIPPER is a trademark of Nantucket Corporation.

  15. Use of Optical Storage Devices as Shared Resources in Local Area Networks

    DTIC Science & Technology

    1989-09-01

    13 3. SERVICE CALLS FOR MS-DOS CD-ROM EXTENSIONS . 14 4. MS-DOS PRIMITIVE GROUPS ....................... 15 5. RAM USAGE FOR VARIOUS LAN...17 2. Service Call Translation to DOS Primitives ............. 19 3. MS-DOS Device Drivers ............................. 21 4. MS-DOS/ROM...directed to I/O devices will be referred to as primitive instruction groups). These primitive instruction groups include keyboard, video, disk, serial

  16. Development of Educational Resources to Include the Teaching of Astronomy in the First Years of the Basic Education. (Spanish Title: Desarrollo de Recursos Pedagógicos Para Incluir la Enseñanza de la Astronomía en los Primeros Años de la Educación Básica.) Desenvolvimento de Recursos Pedagógicos Para Inserir o Ensino de Astronomia nas Séries Iniciais do Ensino Fundamental

    NASA Astrophysics Data System (ADS)

    da Silva Morett, Samara; de Oliveira Souza, Marcelo

    2010-07-01

    In this report will be presented the development of educational resources for the presentation of concepts of astronomy in the early grades of elementary school. This material is composed by presentations developed with the use of new technological resources, by the development of experiments and by the presentation of curiosities related to this field. The experiments were constructed with low cost material in order to allow the students involved to rework them in other occasions. The material presented aims to emphasize the relationship between Astronomy and the daily life of students. The inclusion of Astronomy in elementary school is a way to demonstrate to students how this area is present in an active way in their daily lives. The classes involved in the project participated in a survey with the aim of providing information about the prior knowledge they had about topics in astronomy that were considered during the project. With the experiments conducted, and the aid of new technologies, the astronomical concepts were presented to students of 4th and 5th years of basic education of a municipal school of Campos dos Goytacazes (RJ). After the presentations new data collections were carried out with the aim of verifying the level of learning obtained and it was observed that the method used was an important tool to aid the process of teaching and learning. The project obtained good results. En este informe se presenta el desarrollo de recursos pedagógicos para la presentación de los conceptos de la astronomía en los primeros grados de la escuela primaria. Este material consiste en las presentaciones hechas con el uso de nuevos recursos tecnológicos, haciendo experimentos y análisis de objetos de interés relacionados con este ámbito. Los experimentos fueron construidos con material de bajo costo a fin de que los estudiantes involucrados podrían rehacer en otras ocasiones. El material presentado tiene como objetivo destacar la relación entre la astronomía y la vida cotidiana de los estudiantes. La inclusión de la astronomía en la escuela primaria es una manera de demostrar a los estudiantes cómo este campo está presente de forma activa en su vida cotidiana. Las clases que participan en el proyecto participaron en un estudio con el objetivo de proporcionar información a los conocimientos previos que tenían sobre los temas de la astronomía que se examinaron durante el proyecto. Con los experimentos realizados, y la ayuda de las nuevas tecnologías, conceptos astronómicos fueron presentados a los estudiantes de 4to y 5to año de la educación básica de una escuela municipal de Campos dos Goytacazes (RJ). Después de las presentaciones nuevos datos fueran colectados y se han llevado a cabo con el fin de verificar el nivel de aprendizaje alcanzado y se observó que el método utilizado fue una herramienta importante para ayudar al proceso de enseñanza y aprendizaje. El proyecto logró resultados satisfactorios. Neste trabalho será apresentado o desenvolvimento de recursos pedagógicos para a apresentação de conceitos de astronomia nas séries iniciais do ensino fundamental. Este material é composto por apresentações realizadas com o uso de novos recursos tecnológicos, pela fabricação de experimentos e a discussão de curiosidades relativas a esta área de conhecimento. Os experimentos foram construídos com material de baixo custo com o objetivo de permitir que os alunos envolvidos pudessem refazê-los em outras ocasiões. O material apresentado busca enfatizar a relação entre a astronomia e o cotidiano dos alunos. A inclusão da astronomia no ensino fundamental e uma forma de demonstrar aoestudante como esta área está presente de forma ativa em seu cotidiano. As turmas envolvidas no projeto participaram de uma pesquisa com o objetivo de obter dados relativos ao conhecimento prévio que possuíam sobre os tópicos de astronomia que foram considerados no decorrer do projeto. Com os experimentos desenvolvidos, o auxílio de novas tecnologias, foram apresentados conceitos astronômicos aos alunos do 4º e 5º anos do ensino fundamental de uma escola municipal de Campos dos Goytacazes (RJ). Após as apresentações novas coletas de dados foram realizadas com o intuito de verificar o nível de aprendizado alcançado e foi possível perceber que o método utilizado foi uma importante ferramenta de auxílio para o processo de ensino-aprendizagem. O projeto alcançou resultados satisfatórios.

  17. Unique Regulation of the DosR Regulon in the Beijing Lineage of Mycobacterium tuberculosis.

    PubMed

    Domenech, Pilar; Zou, Jason; Averback, Alexandra; Syed, Nishath; Curtis, Daniele; Donato, Samuel; Reed, Michael B

    2017-01-15

    The DosR regulon, a set of 48 genes normally expressed in Mycobacterium tuberculosis under conditions that inhibit aerobic respiration, is controlled via the DosR-DosS/DosT two-component system. While the regulon requires induction in most M. tuberculosis isolates, for members of the Beijing lineage, its expression is uncoupled from the need for signaling. In our attempts to understand the mechanistic basis for this uncoupling in the Beijing background, we previously reported the identification of two synonymous single-nucleotide polymorphisms (SNPs) within the adjacent Rv3134c gene. In the present study, we have interrogated the impact of these SNPs on dosR expression in wild-type strains, as well as a range of dosR-dosS-dosT mutants, for both Beijing and non-Beijing M. tuberculosis backgrounds. In this manner, we have unequivocally determined that the C601T dosR promoter SNP is the sole requirement for the dramatic shift in the pattern of DosR regulon expression seen in this globally important lineage. Interestingly, we also show that DosT is completely nonfunctional within these strains. Thus, a complex series of evolutionary steps has led to the present-day Beijing DosR phenotype that, in turn, potentially confers a fitness advantage in the face of some form of host-associated selective pressure. Mycobacterium tuberculosis strains of the Beijing lineage have been described as being of enhanced virulence compared to other lineages, and in certain regions, they are associated with the dramatic spread of multidrug-resistant tuberculosis (TB). In terms of trying to understand the functional basis for these broad epidemiological phenomena, it is interesting that, in contrast to the other major lineages, the Beijing strains all constitutively overexpress members of the DosR regulon. Here, we identify the mutational events that led to the evolution of this unique phenotype. In addition, our work highlights the fact that important phenotypic differences exist between distinct M. tuberculosis lineages, with the potential to impact the efficacy of diagnosis, vaccination, and treatment programs. Copyright © 2016 American Society for Microbiology.

  18. The μ3 model of acids and bases: extending the Lewis theory to intermetallics.

    PubMed

    Stacey, Timothy E; Fredrickson, Daniel C

    2012-04-02

    A central challenge in the design of new metallic materials is the elucidation of the chemical factors underlying the structures of intermetallic compounds. Analogies to molecular bonding phenomena, such as the Zintl concept, have proven very productive in approaching this goal. In this Article, we extend a foundational concept of molecular chemistry to intermetallics: the Lewis theory of acids and bases. The connection is developed through the method of moments, as applied to DFT-calibrated Hückel calculations. We begin by illustrating that the third and fourth moments (μ(3) and μ(4)) of the electronic density of states (DOS) distribution tune the properties of a pseudogap. μ(3) controls the balance of states above and below the DOS minimum, with μ(4) then determining the minimum's depth. In this way, μ(3) predicts an ideal occupancy for the DOS distribution. The μ(3)-ideal electron count is used to forge a link between the reactivity of transition metals toward intermetallic phase formation, and that of Lewis acids and bases toward adduct formation. This is accomplished through a moments-based definition of acidity which classifies systems that are electron-poor relative to the μ(3)-ideal as μ(3)-acidic, and those that are electron-rich as μ(3)-basic. The reaction of μ(3) acids and bases, whether in the formation of a Lewis acid/base adduct or an intermetallic phase, tends to neutralize the μ(3) acidity or basicity of the reactants. This μ(3)-neutralization is traced to the influence of electronegativity differences at heteroatomic contacts on the projected DOS curves of the atoms involved. The role of μ(3)-acid/base interactions in intermetallic phases is demonstrated through the examination of 23 binary phases forming between 3d metals, the stability range of the CsCl type, and structural trends within the Ti-Ni system.

  19. Ab-initio investigations for opto-electronic response of (Cd, Zn)Ga2Te4: Promising solar PV materials

    NASA Astrophysics Data System (ADS)

    Sahariya, Jagrati; Soni, Amit; Kumar, Pancham

    2018-04-01

    In this paper, the first principle calculations are performed to analyze the structural, electronic and optical behavior of promising solar materials (Cd,Zn)Ga2Te4. To perform these calculations we have used one of the most accurate Full Potential Linearized Augmented Plane Wave (FP-LAPW) method. The ground state properties of these compounds are confirmed over here after proper examination of energy and charge convergence using Perdew-Burke-Ernzerhof (PBE-sol) exchange correlation potential. The investigations performed such as energy band structure, Density of States (DOS), optical parameters like complex dielectric function and absorption co-efficient are discussed over here to understand the overall response of the chosen system.

  20. Lattice stability and thermal properties of Fe2VAl and Fe2TiSn Heusler compounds

    NASA Astrophysics Data System (ADS)

    Shastri, Shivprasad S.; Pandey, Sudhir K.

    2018-04-01

    Fe2VAl and Fe2TiSn are two full-Heusler compounds with non-magnetic ground states. They have application as potential thermoelectric materials. Along with first-principles electronic structure calculations, phonon calculation is one of the important tools in condensed matter physics and material science. Phonon calculations are important in understanding mechanical properties, thermal properties and phase transitions of periodic solids. A combination of electronic structure code and phonon calculation code - phonopy is employed in this work. The vibrational spectra, phonon DOS and thermal properties are studied for these two Heusler compounds. Two compounds are found to be dynamically stable with absence of negative frequencies (energy) in the phonon band structure.

  1. Ultrafast wavelength multiplexed broad bandwidth digital diffuse optical spectroscopy for in vivo extraction of tissue optical properties

    NASA Astrophysics Data System (ADS)

    Torjesen, Alyssa; Istfan, Raeef; Roblyer, Darren

    2017-03-01

    Frequency-domain diffuse optical spectroscopy (FD-DOS) utilizes intensity-modulated light to characterize optical scattering and absorption in thick tissue. Previous FD-DOS systems have been limited by large device footprints, complex electronics, high costs, and limited acquisition speeds, all of which complicate access to patients in the clinical setting. We have developed a new digital DOS (dDOS) system, which is relatively compact and inexpensive, allowing for simplified clinical use, while providing unprecedented measurement speeds. The dDOS system utilizes hardware-integrated custom board-level direct digital synthesizers and an analog-to-digital converter to generate frequency sweeps and directly measure signals utilizing undersampling at six wavelengths modulated at discrete frequencies from 50 to 400 MHz. Wavelength multiplexing is utilized to achieve broadband frequency sweep measurements acquired at over 97 Hz. When compared to a gold-standard DOS system, the accuracy of optical properties recovered with the dDOS system was within 5.3% and 5.5% for absorption and reduced scattering coefficient extractions, respectively. When tested in vivo, the dDOS system was able to detect physiological changes throughout the cardiac cycle. The new FD-dDOS system is fast, inexpensive, and compact without compromising measurement quality.

  2. Improving Public Reporting and Data Validation for Complex Surgical Site Infections After Coronary Artery Bypass Graft Surgery and Hip Arthroplasty

    PubMed Central

    Calderwood, Michael S.; Kleinman, Ken; Murphy, Michael V.; Platt, Richard; Huang, Susan S.

    2014-01-01

    Background  Deep and organ/space surgical site infections (D/OS SSI) cause significant morbidity, mortality, and costs. Rates are publicly reported and increasingly used as quality metrics affecting hospital payment. Lack of standardized surveillance methods threaten the accuracy of reported data and decrease confidence in comparisons based upon these data. Methods  We analyzed data from national validation studies that used Medicare claims to trigger chart review for SSI confirmation after coronary artery bypass graft surgery (CABG) and hip arthroplasty. We evaluated code performance (sensitivity and positive predictive value) to select diagnosis codes that best identified D/OS SSI. Codes were analyzed individually and in combination. Results  Analysis included 143 patients with D/OS SSI after CABG and 175 patients with D/OS SSI after hip arthroplasty. For CABG, 9 International Classification of Diseases, 9th Revision (ICD-9) diagnosis codes identified 92% of D/OS SSI, with 1 D/OS SSI identified for every 4 cases with a diagnosis code. For hip arthroplasty, 6 ICD-9 diagnosis codes identified 99% of D/OS SSI, with 1 D/OS SSI identified for every 2 cases with a diagnosis code. Conclusions  This standardized and efficient approach for identifying D/OS SSI can be used by hospitals to improve case detection and public reporting. This method can also be used to identify potential D/OS SSI cases for review during hospital audits for data validation. PMID:25734174

  3. Antibiotic and Duration of Perioperative Prophylaxis Predicts Surgical Site Infection in Head and Neck Surgery.

    PubMed

    Langerman, Alexander; Thisted, Ronald; Hohmann, Samuel; Howell, Michael

    2016-06-01

    To examine the effect of giving antibiotics on the day of surgery (DOS) vs DOS and first postoperative day (DOS+1) for prophylaxis against surgical site infection (SSI) in clean-contaminated head and neck surgery (CCHNS). Retrospective multi-institution analysis using University HealthSystem Consortium data. A multivariate logistic regression model of 8836 discharge records from patients undergoing CCHNS was used to determine the odds of SSI for antibiotic agent/duration combinations. Ninety-two academic and affiliated medical centers from 2008 to 2011. Ampicillin/sulbactam, clindamycin, cefazolin + metronidazole, and cefazolin alone were the most common antibiotics. For patients receiving antibiotics only on DOS, there was no significant difference in odds of SSI based on antibiotic choice. When given on the DOS and DOS+1, patients receiving ampicillin/sulbactam had a reduction in odds of SSI by over two-thirds (odds ratio [OR], 0.28 [95% confidence interval, 0.13-0.61], P = .001, compared with ampicillin/sulbactam on DOS only), whereas this effect was not seen with clindamycin (1.82 [0.93-3.56], P = .078, compared with clindamycin on DOS only). Prolonging clindamycin beyond the DOS was associated with a higher odds of SSI compared with DOS-only ampicillin/sulbactam (OR, 2.66; 95% CI, 1.33-5.30; P = .006). These relationships held in a subset of physicians and hospitals that used multiple different regimens. DOS+1 regimens were not associated with an increased odds of antibiotic-induced complications. Prolonging ampicillin/sulbactam beyond the day of surgery may have a protective effect against SSI, and 1 or more days of ampicillin/sulbactam may be preferable to multiple days of clindamycin. New randomized trials are needed to define the ideal regimen for CCHNS. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2016.

  4. Development of large area nanostructured silicon-hydrogen alloy material with improved stability for solar cell application by argon dilution method

    NASA Astrophysics Data System (ADS)

    Dey, Arka; Das, Mrinmay; Datta, Joydeep; Jana, Rajkumar; Dhar, Joydeep; Sil, Sayantan; Biswas, Debasish; Banerjee, Chandan; Ray, Partha Pratim

    2016-07-01

    Here we have presented the results of large area (30 × 30 cm2) silicon-hydrogen alloy material and solar cell by argon dilution method. As an alternative to hydrogen dilution, argon dilution method has been applied to develop single junction solar cell with appreciable stability. Optimization of deposition conditions revealed that 95% argon dilution gives a nanostructured material with improved transport property and less light induced degradation. The minority carrier diffusion length (L d ) and mobility-lifetime (μτ) product of the material with 95% argon dilution degrades least after light soaking. Also the density of states (DOS) below conduction level reveals that this material is less defective. Solar cell with this argon diluted material has been fabricated with all the layers deposited by argon dilution method. Finally we have compared the argon diluted solar cell results with the optimized hydrogen diluted solar cell. Light soaking study proves that it is possible to develop stable solar cell on large area by argon dilution method and that the degradation of argon diluted solar cell is less than that of hydrogen diluted one. [Figure not available: see fulltext.

  5. Disk Operating System--DOS. Teacher Packet. Learning Activity Packets.

    ERIC Educational Resources Information Center

    Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    The Learning Activity Packets (LAPs) contained in this manual are designed to assist the beginning user in understanding DOS (Disk Operating System). LAPs will not work with any version below DOS Version 3.0 and do not address the enhanced features of versions 4.0 or higher. These elementary activities cover only the DOS commands necessary to…

  6. Band gap engineering of BC2N for nanoelectronic applications

    NASA Astrophysics Data System (ADS)

    Lim, Wei Hong; Hamzah, Afiq; Ahmadi, Mohammad Taghi; Ismail, Razali

    2017-12-01

    The BC2N as an example of boron-carbon-nitride (BCN), has the analogous structure as the graphene and boron nitride. It is predicted to have controllable electronic properties. Therefore, the analytical study on the engineer-able band gap of the BC2N is carried out based on the schematic structure of BC2N. The Nearest Neighbour Tight Binding (NNTB) model is employed with the dispersion relation and the density of state (DOS) as the main band gap analysing parameter. The results show that the hopping integrals having the significant effect on the band gap, band structure and DOS of BC2N nanowire (BC2NNW) need to be taken into consideration. The presented model indicates consistent trends with the published computational results around the Dirac points with the extracted band gap of 0.12 eV. Also, it is distinguished that wide energy gap of boron nitride (BN) is successfully narrowed by this carbon doped material which assures the application of BC2N on the nanoelectronics and optoelectronics in the near future.

  7. Observational Assessment of Preschool Disruptive Behavior, Part II: validity of the Disruptive Behavior Diagnostic Observation Schedule (DB-DOS).

    PubMed

    Wakschlag, Lauren S; Briggs-Gowan, Margaret J; Hill, Carri; Danis, Barbara; Leventhal, Bennett L; Keenan, Kate; Egger, Helen L; Cicchetti, Domenic; Burns, James; Carter, Alice S

    2008-06-01

    To examine the validity of the Disruptive Behavior Diagnostic Observation Schedule (DB-DOS), a new observational method for assessing preschool disruptive behavior. A total of 327 behaviorally heterogeneous preschoolers from low-income environments comprised the validation sample. Parent and teacher reports were used to identify children with clinically significant disruptive behavior. The DB-DOS assessed observed disruptive behavior in two domains, problems in Behavioral Regulation and Anger Modulation, across three interactional contexts: Examiner Engaged, Examiner Busy, and Parent. Convergent and divergent validity of the DB-DOS were tested in relation to parent and teacher reports and independently observed behavior. Clinical validity was tested in terms of criterion and incremental validity of the DB-DOS for discriminating disruptive behavior status and impairment, concurrently and longitudinally. DB-DOS scores were significantly associated with reported and independently observed behavior in a theoretically meaningful fashion. Scores from both DB-DOS domains and each of the three DB-DOS contexts contributed uniquely to discrimination of disruptive behavior status, concurrently and predictively. Observed behavior on the DB-DOS also contributed incrementally to prediction of impairment over time, beyond variance explained by meeting DSM-IV disruptive behavior disorder symptom criteria based on parent/teacher report. The multidomain, multicontext approach of the DB-DOS is a valid method for direct assessment of preschool disruptive behavior. This approach shows promise for enhancing accurate identification of clinically significant disruptive behavior in young children and for characterizing subtypes in a manner that can directly inform etiological and intervention research.

  8. The influence of cumulus cells during in vitro fertilization of buffalo (Bubalus bubalis) denuded oocytes that have undergone vitrification.

    PubMed

    Attanasio, Laura; De Rosa, Anna; De Blasi, Marina; Neglia, Gianluca; Zicarelli, Luigi; Campanile, Giuseppe; Gasparrini, Bianca

    2010-11-01

    The aim of this work was to evaluate whether providing a support of cumulus cells during IVF of buffalo denuded oocytes submitted to vitrification-warming enhances their fertilizing ability. In vitro matured denuded oocytes were vitrified by Cryotop in 20% EG + 20% of DMSO and 0.5 M sucrose and warmed into decreasing concentrations of sucrose (1.25 M-0.3M). Oocytes that survived vitrification were fertilized: 1) in the absence of a somatic support (DOs); 2) in the presence of bovine cumulus cells in suspension (DOs+susp); 3) on a bovine cumulus monolayer (DOs+monol); and 4) with intact bovine COCs in a 1:1 ratio (DOs+COCs). In vitro matured oocytes were fertilized and cultured to the blastocyst stage as a control. An increased cleavage rate was obtained from DOs+COCs (60.9%) compared to DOs, DOs+susp (43.6 and 38.4, respectively; P < 0.01) and DOs+monol (47.5%; P < 0.05). Interestingly, cleavage rate of DOs+COCs was similar to that of fresh control oocytes (67.8%). However, development to blastocysts significantly decreased in all vitrification groups compared to the control (P < 0.01). In conclusion the co-culture with intact COCs during IVF completely restores fertilizing capability of buffalo denuded vitrified oocytes, without improving blastocyst development. Copyright © 2010 Elsevier Inc. All rights reserved.

  9. DOS cones along atomic chains

    NASA Astrophysics Data System (ADS)

    Kwapiński, Tomasz

    2017-03-01

    The electron transport properties of a linear atomic chain are studied theoretically within the tight-binding Hamiltonian and the Green’s function method. Variations of the local density of states (DOS) along the chain are investigated. They are crucial in scanning tunnelling experiments and give important insight into the electron transport mechanism and charge distribution inside chains. It is found that depending on the chain parity the local DOS at the Fermi level can form cone-like structures (DOS cones) along the chain. The general condition for the local DOS oscillations is obtained and the linear behaviour of the local density function is confirmed analytically. DOS cones are characterized by a linear decay towards the chain which is in contrast to the propagation properties of charge density waves, end states and Friedel oscillations in one-dimensional systems. We find that DOS cones can appear due to non-resonant electron transport, the spin-orbit scattering or for chains fabricated on a substrate with localized electrons. It is also shown that for imperfect chains (e.g. with a reduced coupling strength between two neighboring sites) a diamond-like structure of the local DOS along the chain appears.

  10. Influence of Ca2+ on the mechanosensitivity of the hair cells in the lateral line organs of Necturus maculosus.

    PubMed

    Jørgensen, F

    1983-08-01

    The degree of synchronization (DOS) between the afferent spike activity from one stitch of the lateral line of Necturus maculosus (in vivo) and the mechanical stimulation of one neuromast of the same stitch was measured under different circumstances. The DOS was found to be independent of changes in the concentration of monovalent cations (Na+, K+ and choline+) in the bulk solution at high Ca concentration (1 mM). DOS was also independent of the Ca concentration in the range 1 mM-1 microM in Tris-HCl buffer, but was markedly reduced at Ca = 10 microM in MOPS-KOH buffer. The reduced DOS, however, could be restored by addition of 10-20 mM KCl. 5 mM of 4-aminopyridine did not influence the DOS at high Ca concentration, but completely reduced DOS at Ca = 10 microM. D600 (a methoxy derivative of verapamil) decreased DOS both at high and low Ca concentration.

  11. Dissolved organic sulfur in the ocean: Biogeochemistry of a petagram inventory

    NASA Astrophysics Data System (ADS)

    Ksionzek, Kerstin B.; Lechtenfeld, Oliver J.; McCallister, S. Leigh; Schmitt-Kopplin, Philippe; Geuer, Jana K.; Geibert, Walter; Koch, Boris P.

    2016-10-01

    Although sulfur is an essential element for marine primary production and critical for climate processes, little is known about the oceanic pool of nonvolatile dissolved organic sulfur (DOS). We present a basin-scale distribution of solid-phase extractable DOS in the East Atlantic Ocean and the Atlantic sector of the Southern Ocean. Although molar DOS versus dissolved organic nitrogen (DON) ratios of 0.11 ± 0.024 in Atlantic surface water resembled phytoplankton stoichiometry (sulfur/nitrogen ~ 0.08), increasing dissolved organic carbon (DOC) versus DOS ratios and decreasing methionine-S yield demonstrated selective DOS removal and active involvement in marine biogeochemical cycles. Based on stoichiometric estimates, the minimum global inventory of marine DOS is 6.7 petagrams of sulfur, exceeding all other marine organic sulfur reservoirs by an order of magnitude.

  12. Recent Optical and SEM Characterization of Genesis Solar Wind Concentrator Diamond on Silicon Collector

    NASA Technical Reports Server (NTRS)

    Allton, Judith H.; Rodriquez, M. C.; Burkett, P. J.; Ross, D. K.; Gonzalez, C. P.; McNamara, K. M.

    2013-01-01

    One of the 4 Genesis solar wind concentrator collectors was a silicon substrate coated with diamond-like carbon (DLC) in which to capture solar wind. This material was designed for analysis of solar nitrogen and noble gases [1, 2]. This particular collector fractured during landing, but about 80% of the surface was recovered, including a large piece which was subdivided in 2012 [3, 4, 5]. The optical and SEM imaging and analysis described below supports the subdivision and allocation of the diamond-on-silicon (DOS) concentrator collector.

  13. Kambersky Damping in L10 Magnetic Materials of Ordered and Disordered States with Substitutional Defects

    NASA Astrophysics Data System (ADS)

    Qu, Tao; Victora, Randall

    2015-03-01

    L10 phase alloys with high magnetic anisotropy play a key role in spintronic devices. The damping constant α represents the elimination of the magnetic energy and affects the efficiency of devices. However, the intrinsic Kambersky damping reported experimentally differs among investigators and the effect of defects on α is never investigated. Here, we apply Kambersky's torque correlation technique, within the tight-binding method, to L10 ordered and disordered alloys FePt, FePd,CoPt and CoPd. In the ordered phase, CoPt has the largest damping of 0.067 while FePd has the minimum value of 0.009 at room temperature. The calculated damping value of FePt and FePd agrees well with experiment. Artificially shifting Ef, as might be accomplished by doping with impurity atoms, shows that α follows the density of states (DOS) at Ef in these four L10 alloys. We introduce lattice defects through exchanging the positions of 3d and non-3d transition elements in 36 atom supercells. The damping increases with reduced degree of chemical order, owing to the enhanced spin-flip channel allowed by the broken symmetry. This prediction is confirmed by measurements in FePt. It is demonstrated that this corresponds to an enhanced DOS at the Fermi level, owing to the rounding of the DOS with loss of long-range order. This work was supported primarily by C-SPIN (one of the six SRC STAR-net Centers) and partly by the MRSEC Program under Contract No. DMR-0819885.

  14. DOS.

    ERIC Educational Resources Information Center

    Traven, Bill

    1988-01-01

    Discusses using the DOS PATH command (for MS-DOS) to enable the microcomputer user to move from directory to directory on a hard drive. Lists the commands to be programed, gives examples, and explains the use of each. (MVL)

  15. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Busbey, A.B.

    A number of methods and products, both hardware and software, to allow data exchange between Apple Macintosh computers and MS-DOS based systems. These included serial null modem connections, MS-DOS hardware and/or software emulation, MS-DOS disk-reading hardware and networking.

  16. Simplified expressions that incorporate finite pulse effects into coherent two-dimensional optical spectra.

    PubMed

    Do, Thanh Nhut; Gelin, Maxim F; Tan, Howe-Siang

    2017-10-14

    We derive general expressions that incorporate finite pulse envelope effects into a coherent two-dimensional optical spectroscopy (2DOS) technique. These expressions are simpler and less computationally intensive than the conventional triple integral calculations needed to simulate 2DOS spectra. The simplified expressions involving multiplications of arbitrary pulse spectra with 2D spectral response function are shown to be exactly equal to the conventional triple integral calculations of 2DOS spectra if the 2D spectral response functions do not vary with population time. With minor modifications, they are also accurate for 2D spectral response functions with quantum beats and exponential decay during population time. These conditions cover a broad range of experimental 2DOS spectra. For certain analytically defined pulse spectra, we also derived expressions of 2D spectra for arbitrary population time dependent 2DOS spectral response functions. Having simpler and more efficient methods to calculate experimentally relevant 2DOS spectra with finite pulse effect considered will be important in the simulation and understanding of the complex systems routinely being studied by using 2DOS.

  17. Rhenium-osmium isotope and highly-siderophile-element abundance systematics of angrite meteorites

    NASA Astrophysics Data System (ADS)

    Riches, Amy J. V.; Day, James M. D.; Walker, Richard J.; Simonetti, Antonio; Liu, Yang; Neal, Clive R.; Taylor, Lawrence A.

    2012-11-01

    Coupled 187Os/188Os compositions and highly-siderophile-element (HSE: Os, Ir, Ru, Pt, Pd, and Re) abundance data are reported for eight angrite achondrite meteorites that include quenched- and slowly-cooled textural types. These data are combined with new major- and trace-element concentrations determined for bulk-rock powder fractions and constituent mineral phases, to assess angrite petrogenesis. Angrite meteorites span a wide-range of HSE abundances from <0.005 ppb Os (e.g., Northwest Africa [NWA] 1296; Angra dos Reis) to >100 ppb Os (NWA 4931). Chondritic to supra-chondritic 187Os/188Os (0.1201-0.2127) measured for Angra dos Reis and quenched-angrites correspond to inter- and intra-sample heterogeneities in Re/Os and HSE abundances. Quenched-angrites have chondritic-relative rare-earth-element (REE) abundances at 10-15×CI-chondrite, and their Os-isotope and HSE abundance variations represent mixtures of pristine uncontaminated crustal materials that experienced addition (<0.8%) of exogenous chondritic materials during or after crystallization. Slowly-cooled angrites (NWA 4590 and NWA 4801) have fractionated REE-patterns, chondritic to sub-chondritic 187Os/188Os (0.1056-0.1195), as well as low-Re/Os (0.03-0.13), Pd/Os (0.071-0.946), and relatively low-Pt/Os (0.792-2.640). Sub-chondritic 187Os/188Os compositions in NWA 4590 and NWA 4801 are unusual amongst planetary basalts, and their HSE and REE characteristics may be linked to melting of mantle sources that witnessed prior basaltic melt depletion. Angrite HSE-Yb systematics suggest that the HSE behaved moderately-incompatibly during angrite magma crystallization, implying the presence of metal in the crystallizing assemblage. The new HSE abundance and 187Os/188Os compositions indicate that the silicate mantle of the angrite parent body(ies) (APB) had HSE abundances in chondritic-relative proportions but at variable abundances at the time of angrite crystallization. The HSE systematics of angrites are consistent with protracted post-core formation accretion of materials with chondritic-relative abundances of HSE to the APB, and these accreted materials were rapidly, yet inefficiently, mixed into angrite magma source regions early in Solar System history.

  18. Balancing Act

    Cancer.gov

    Part of being an Active, More Powerful You means finding balance in your daily life: taking on the Must-dos and finding time for some Should Dos and Want-to-Dos. Sometimes, emotions and commitments can come into play and upset the balance.

  19. Accurate description of charge transport in organic field effect transistors using an experimentally extracted density of states

    NASA Astrophysics Data System (ADS)

    Roelofs, W. S. C.; Mathijssen, S. G. J.; Janssen, R. A. J.; de Leeuw, D. M.; Kemerink, M.

    2012-02-01

    The width and shape of the density of states (DOS) are key parameters to describe the charge transport of organic semiconductors. Here we extract the DOS using scanning Kelvin probe microscopy on a self-assembled monolayer field effect transistor (SAMFET). The semiconductor is only a single monolayer which has allowed extraction of the DOS over a wide energy range, pushing the methodology to its fundamental limit. The measured DOS consists of an exponential distribution of deep states with additional localized states on top. The charge transport has been calculated in a generic variable range-hopping model that allows any DOS as input. We show that with the experimentally extracted DOS an excellent agreement between measured and calculated transfer curves is obtained. This shows that detailed knowledge of the density of states is a prerequisite to consistently describe the transfer characteristics of organic field effect transistors.

  20. Field dependence of the vortex core size probed by scanning tunneling microscopy

    DOE PAGES

    Fente, A.; Herrera, E.; Guillamón, I.; ...

    2016-07-29

    We study the spatial distribution of the density of states (DOS) at zero bias N(r) in the mixed state of single and multigap superconductors. We provide an analytic expression for N(r) based on deGennes' relationship between DOS and the order parameter that reproduces well scanning tunneling microscopy (STM) data in several superconducting materials. In the single gap superconductor β-Bi 2 Pd, we find that N(r) is governed by a length scale ξ H =more » $$\\sqrt{Φ0/2πH}$$ which decreases in rising fields. The vortex core size $C$ ∝ (d Δ/dr| r→0) ₋1 differs from ξ H by a material dependent numerical factor. The new data on the tunneling conductance and vortex lattice of the 2H-NbSe 1.8S 0.2 show the in-plane isotropic vortices, suggesting that substitutional scattering removes the in-plane anisotropy found in the two-gap superconductor 2H-NbSe 2. We fit the tunneling conductance of 2H-NbSe 1.8S 0.2 to a two gap model and calculate the vortex core size $C$ for each band. We find that $C$ is field independent and has the same value for both bands. We also analyze the two-band superconductor 2H-NbSe 2 and find the same result. Lastly, we conclude that, independently of the magnetic field induced variation of the order parameter values in both bands, the spatial variation of the order parameter close to the vortex core is the same for all bands.« less

  1. Visiting two objects in the field of the ring galaxy HRG 2302

    NASA Astrophysics Data System (ADS)

    Faúndez-Abans, M.; Reshetnikov, V. P.; de Oliveira-Abans, M.; Krabbe, A. C.; da Rocha-Poppe, P. C.; Fernandes-Martin, V. A.; Amôres, E. B.; Freitas-Lemes, P.

    2015-02-01

    Aims: We investigate the nature of two galaxies that are located in the field of the ring galaxy HRG 2302. Methods: This study is based on direct BVRI imaging and long-slit spectrophotometric data in the range of 4000-9500 Å obtained with the 1.6 m telescope of the Observatório do Pico dos Dias, Brazil. The spectra were used to determine the radial velocity. Results: The primary objective of the retrieval of the photometric data was to identify the fine structures of objects H and I. In addition, we performed image processing and made a photometric analysis to obtain the integrated standard BVRI magnitudes. The contour maps show evidence of material connecting both galaxies, suggesting that they might be interacting close companions. We estimated redshifts of z = 0.0689 and z = 0.0692. The spectra of the two galaxies resemble those of an early-type galaxy. The fact that the objects have a small radial-velocity difference and the structures around object I suggest an ongoing tidal interaction between the two galaxies. Conclusions: The H-I system seems to be composed of two early-type spiral galaxies (S0/Sa). Galaxy I shows evidence of tidal perturbation: an off-centered bulge, some material extending along the NE direction, and structures that have been enhanced by image filtering procedures. There are some dwarf objects around it. Neither object shows evidence of nuclear activity. Based on observations carried out at the Observatório do Pico dos Dias (OPD), which is operated by LNA/MCTI, and public data from the LNA database.

  2. Field dependence of the vortex core size probed by scanning tunneling microscopy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fente, A.; Herrera, E.; Guillamón, I.

    We study the spatial distribution of the density of states (DOS) at zero bias N(r) in the mixed state of single and multigap superconductors. We provide an analytic expression for N(r) based on deGennes' relationship between DOS and the order parameter that reproduces well scanning tunneling microscopy (STM) data in several superconducting materials. In the single gap superconductor β-Bi 2 Pd, we find that N(r) is governed by a length scale ξ H =more » $$\\sqrt{Φ0/2πH}$$ which decreases in rising fields. The vortex core size $C$ ∝ (d Δ/dr| r→0) ₋1 differs from ξ H by a material dependent numerical factor. The new data on the tunneling conductance and vortex lattice of the 2H-NbSe 1.8S 0.2 show the in-plane isotropic vortices, suggesting that substitutional scattering removes the in-plane anisotropy found in the two-gap superconductor 2H-NbSe 2. We fit the tunneling conductance of 2H-NbSe 1.8S 0.2 to a two gap model and calculate the vortex core size $C$ for each band. We find that $C$ is field independent and has the same value for both bands. We also analyze the two-band superconductor 2H-NbSe 2 and find the same result. Lastly, we conclude that, independently of the magnetic field induced variation of the order parameter values in both bands, the spatial variation of the order parameter close to the vortex core is the same for all bands.« less

  3. Teaching Bibliometric Analysis and MS/DOS Commands.

    ERIC Educational Resources Information Center

    Dou, Henri; And Others

    1988-01-01

    Outlines the steps involved in bibliometric studies, and demonstrates the ability to execute simple studies on microcomputers by downloading files using only the capability of MS/DOS. Detailed illustrations of the MS/DOS commands used are provided. (eight references) (CLB)

  4. DYNAMIC OSCILLATORY STRETCHING EFFICACY ON HAMSTRING EXTENSIBILITY AND STRETCH TOLERANCE: A RANDOMIZED CONTROLLED TRIAL

    PubMed Central

    Tee, Jason Cameron; Stewart, Aimee

    2017-01-01

    Background While static stretch (SS), proprioceptive neuromuscular facilitation (PNF) and oscillatory physiological mobilization techniques are documented to have positive effects on a range of motion (ROM), there are no reports on the effect of dynamic oscillatory stretching (DOS), a technique that combines these three techniques, on hamstring extensibility. Purpose To determine whether DOS improves hamstring extensibility and stretch tolerance to a greater degree than SS in asymptomatic young participants. Study Design Randomized Controlled Trial. Methods Sixty participants (47 females, 13 males, mean age 22 ± 1 years, height 166 ± 6 centimeters, body mass 67.6 ± 9.7 kg) completed a passive straight leg (SLR) to establish hamstring extensibility and stretch tolerance as perceived by participants, using a visual analogue scale (VAS). Participants were randomly assigned to one of two treatment groups (SS or DOS) or a placebo control (20 per group). Tests were repeated immediately following and one hour after each intervention. Data were assessed using a two-way repeated measure analysis of variance (ANOVA) and Tukey's post hoc test. Results Immediately post-intervention, there was a significant improvement in the hamstring extensibility as measured by the SLR in both the SS and DOS groups, with the DOS group exhibiting a significantly greater increase than the SS group (Control 73 ± 12°, SS 86 ± 8°, DOS 94 ± 11°, p < 0.001). One hour post-intervention, hamstring extensibility in the DOS group remained elevated, while the SS group no longer differed from the control group (Control 73 ± 12°, SS 80 ± 8°, DOS 89 ± 12°, p = 0.001). Furthermore, the stretch tolerance remained significantly elevated for the SS group, but there was no difference between the control and DOS groups, (Control 4.6 ± 1.3, SS 5.9 ± 0.8, DOS 4.3 ± 1.0 AU, p < 0.001). Conclusion DOS was more effective than SS at achieving an immediate increase in hamstring extensibility, and DOS demonstrated an increased stretch tolerance one-hour post-intervention. Level of evidence 2C PMID:28593083

  5. Measurements of degree of sensitization (DoS) in aluminum alloys using EMAT ultrasound.

    PubMed

    Li, Fang; Xiang, Dan; Qin, Yexian; Pond, Robert B; Slusarski, Kyle

    2011-07-01

    Sensitization in 5XXX aluminum alloys is an insidious problem characterized by the gradual formation and growth of beta phase (Mg(2)Al(3)) at grain boundaries, which increases the susceptibility of alloys to intergranular corrosion (IGC) and intergranular stress-corrosion cracking (IGSCC). The degree of sensitization (DoS) is currently quantified by the ASTM G67 Nitric Acid Mass Loss Test, which is destructive and time consuming. A fast, reliable, and non-destructive method for rapid detection and the assessment of the condition of DoS in AA5XXX aluminum alloys in the field is highly desirable. In this paper, we describe a non-destructive method for measurements of DoS in aluminum alloys with an electromagnetic acoustic transducer (EMAT). AA5083 aluminum alloy samples were sensitized at 100°C with processing times varying from 7days to 30days. The DoS of sensitized samples was first quantified with the ASTM 67 test in the laboratory. Both ultrasonic velocity and attenuation in sensitized specimens were then measured using EMAT and the results were correlated with the DoS data. We found that the longitudinal wave velocity was almost a constant, independent of the sensitization, which suggests that the longitudinal wave can be used to determine the sample thickness. The shear wave velocity and especially the shear wave attenuation are sensitive to DoS. Relationships between DoS and the shear velocity, as well as the shear attenuation have been established. Finally, we performed the data mining to evaluate and improve the accuracy in the measurements of DoS in aluminum alloys with EMAT. Copyright © 2010 Elsevier B.V. All rights reserved.

  6. Application of Three-Dimensional Models for the Teaching of Time Zones. (Breton Title: Aplicação de Modelos Tridimensionais Para o Ensino de Fusos Horários.) Aplicación de Modelos Tridimensionales Para la Enseñanza de Husos Horarios

    NASA Astrophysics Data System (ADS)

    Azevedo Sobreira, Paulo Henrique

    2012-07-01

    There are several interesting astronomical topics that must be addressed in the High School and Elementary/Middle School in the disciplines of Geography and of Sciences. Among them, the topic of time zones which is one of the most important to understand the correlation of the Earth's rotation and its implications on daily activities of citizens in local scale, regional and global scales which involve problems of time differences. For the teaching of time zones in the lessons of Geography, for example, there are bi-dimensional representations of thematic maps of world time zones, textbooks and atlas. It happens that teachers face some difficulties to permit its students to view three-dimensionally this astronomical phenomenon from the textbooks available in schools. The aim of this paper is to present two proposals with low-cost materials, which allow the preparation of three-dimensional models for the teaching of time zones. Há vários temas astronômicos interessantes que devem ser trabalhados nos Ensinos Médio e Fundamental, nas disciplinas de Geografia e de Ciências. Entre eles, o tema dos fusos horários que é um dos mais importantes para se correlacionar a rotação da Terra e suas implicações nas atividades cotidianas dos cidadãos em escala local, regional e global, que envolvem problemas de diferenças horárias. Para o ensino dos fusos horários nas aulas de Geografia, por exemplo, há representações bidimensionais de mapas temáticos de fusos horários mundiais, nos livros didáticos e nos atlas. Ocorre que os professores enfrentam algumas dificuldades para possibilitar aos seus alunos a visão tridimensional deste fenômeno astronômico, a partir dos materiais didáticos disponíveis nas escolas. O objetivo deste trabalho é apresentar duas propostas para a confecção de materiais de baixo custo, que possibilitem a elaboração de modelos tridimensionais para o ensino dos fusos horários. Hay algunos temas astronómicos interesantes que se deben trabajar en la enseñanza media y básica, en las asignaturas de Geografía y de Ciencias. Entre ellos, el de los husos horarios que es uno de los más importantes para correlacionar la rotación de la Tierra y sus implicaciones en las actividades diarias de los ciudadanos en escala local, regional y global, y en general, cuestiones que implican problemas de las diferencias horarias. Para la enseñanza de los husos horarios en las clases de Geografía, por ejemplo, hay representaciones bidimensionales de los mapas temáticos de husos horarios mundiales, en libros y atlas didácticos. Sin embargo, los profesores se enfrentan con algunas dificultades para hacer posible que sus alumnos tengan una visión tridimensional de este fenómeno astronómico, usando los materiales didácticos disponibles en las escuelas. El objetivo de este trabajo es presentar la construcción de dos propuestas de materiales de bajo costo, que hacen posible la elaboración de modelos tridimensionales para la enseñanza de los husos horarios.

  7. A Astronomia no Ensino Superior Brasileiro entre 1808 e 1889

    NASA Astrophysics Data System (ADS)

    Bretones, Paulo S.; Videira, Antonio A. P.

    2003-05-01

    Este artigo apresenta os principais eventos ocorridos na história do ensino de astronomia nos cursos superiores que existiram no Brasil desde a chegada da Família Real portuguesa em 1808 até o final do período monárquico. Para compor esse esboço histórico, utilizamos, principalmente, livros didáticos, regulamentos, decretos e leis responsáveis pelas organizações dos conteúdos oferecidos e das carreiras dos responsáveis pela disciplina. Na análise do material empregado, investigamos a presença de concepções filosóficas e científicas, que podem ter norteado os conteúdos disciplinares. Não realizamos nenhuma comparação com o ensino de astronomia em outros países. Concluímos mostrando que o estudo de astronomia, durante o período monárquico, foi mais direcionado para a formação d engenheiros do que astrônomos. Gostaríamos de observar que o presente artigo não tem a pretensão de abordar o assunto de maneira completa e detalhada.

  8. Creating comics in physics lessons: an educational practice

    NASA Astrophysics Data System (ADS)

    Albrecht, Evonir; Voelzke, Marcos Rincon

    2012-06-01

    This article presents the results from an intervention program with 119 students during physics and astronomy lessons. This program has taken place in the public school "Colônia dos Pescadores" in the City of Caraguatatuba, State of São Paulo. The goal is to show the importance and possibility of learning with support materials, either in the classroom or at home,created by the learners themselves. The results show that students can demonstrate their creativity while building up their own knowledge related to Astronomy as they are able to produce comic strips about the theme afterwards.

  9. Thermomechanical Multiaxial Fatigue Testing Capability Developed

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Structural components in aeronautical gas turbine engines typically experience multiaxial states of stress under nonisothermal conditions. To estimate the durability of the various components in the engine, one must characterize the cyclic deformation and fatigue behavior of the materials used under thermal and complex mechanical loading conditions. To this end, a testing protocol and associated test control software were developed at the NASA Lewis Research Center for thermomechanical axial-torsional fatigue tests. These tests are to be performed on thin-walled, tubular specimens fabricated from the cobalt-based superalloy Haynes 188. The software is written in C and runs on an MS-DOS based microcomputer.

  10. 28 CFR 51.20 - Form of submissions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... megabyte MS-DOS formatted diskettes; 5 1/4″ 1.2 megabyte MS-DOS formatted floppy disks; nine-track tape... provided in hard copy. (c) All magnetic media shall be clearly labeled with the following information: (1... a disk operating system (DOS) file, it shall be formatted in a standard American Standard Code for...

  11. Whenever You Use a Computer You Are Using a Program Called an Operating System.

    ERIC Educational Resources Information Center

    Cook, Rick

    1984-01-01

    Examines design, features, and shortcomings of eight disk-based operating systems designed for general use that are popular or most likely to affect the future of microcomputing. Included are the CP/M family, MS-DOS, Apple DOS/ProDOS, Unix, Pick, the p-System, TRSDOS, and Macintosh/Lisa. (MBR)

  12. 76 FR 58074 - 30-Day Notice of Proposed Information Collection: DS-7001 and DS-7005, DOS-Sponsored Academic...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-19

    ...-7001 and DS- 7005, DOS-Sponsored Academic Exchange Program Application, OMB Control Number 1405-0138.... Title of Information Collection: DOS-Sponsored Academic Exchange Program Application. OMB Control Number... Academic Exchange Program. Estimated Number of Respondents: 7160 (For DS-7001, 3842 estimated; for DS-7005...

  13. First-principle calculation of the electronic structure, DOS and effective mass TlInSe2

    NASA Astrophysics Data System (ADS)

    Ismayilova, N. A.; Orudzhev, G. S.; Jabarov, S. H.

    2017-05-01

    The electronic structure, density of states (DOS), effective mass are calculated for tetragonal TlInSe2 from first principle in the framework of density functional theory (DFT). The electronic structure of TlInSe2 has been investigated by Quantum Wise within GGA. The calculated band structure by Hartwigsen-Goedecker-Hutter (HGH) pseudopotentials (psp) shows both the valence band maximum and conduction band minimum located at the T point of the Brillouin zone. Valence band maximum at the T point and the surrounding parts originate mainly from 6s states of univalent Tl ions. Bottom of the conduction band is due to the contribution of 6p-states of Tl and 5s-states of In atoms. Calculated DOS effective mass for holes and electrons are mDOS h∗ = 0.830m e, mDOS h∗ = 0.492m e, respectively. Electron effective masses are fairly isotropic, while the hole effective masses show strong anisotropy. The calculated electronic structure, density of states and DOS effective masses of TlInSe2 are in good agreement with existing theoretical and experimental results.

  14. A Semi-Analytical Extraction Method for Interface and Bulk Density of States in Metal Oxide Thin-Film Transistors

    PubMed Central

    Chen, Weifeng; Wu, Weijing; Zhou, Lei; Xu, Miao; Wang, Lei; Peng, Junbiao

    2018-01-01

    A semi-analytical extraction method of interface and bulk density of states (DOS) is proposed by using the low-frequency capacitance–voltage characteristics and current–voltage characteristics of indium zinc oxide thin-film transistors (IZO TFTs). In this work, an exponential potential distribution along the depth direction of the active layer is assumed and confirmed by numerical solution of Poisson’s equation followed by device simulation. The interface DOS is obtained as a superposition of constant deep states and exponential tail states. Moreover, it is shown that the bulk DOS may be represented by the superposition of exponential deep states and exponential tail states. The extracted values of bulk DOS and interface DOS are further verified by comparing the measured transfer and output characteristics of IZO TFTs with the simulation results by a 2D device simulator ATLAS (Silvaco). As a result, the proposed extraction method may be useful for diagnosing and characterising metal oxide TFTs since it is fast to extract interface and bulk density of states (DOS) simultaneously. PMID:29534492

  15. Actividad Solar Desde EL Espacio

    NASA Astrophysics Data System (ADS)

    Rovira, M. G.

    1990-11-01

    RESUMEN. Se describen los principales descubrimientos realizados por los arti+iciales con instrumentos dedicados a la observaci6n del Sol, durante los dos ultimos ciclos de su acti vi dad. La observaci6n el espacio ha permitido cubrir todas las zonas del espectro no observables desde tierra1 desde el ultravioleta hasta la radiaci6n gamma. Se hace referencia, en particular, a los resultados producidos por los dos grandes observatorios: el Skylab y el SMM. Este ultimo incluy6 un conjunto de instrumentos especialmente coordinados para observar en detalle las fulguraciones solares. Es un resumen para astr6nomos no especializados en la fisica solar, en el que se muestra que la gran riqueza del material observacional acumulado ha resuelto problemas preexistentes y, al mismo tiempo, ha abierto numerosos interrogantes a los que se buscar respuesta con la instrumentaci6n en desarrollo. Finalmente, se mencionan las caracteristicas de los proyectados para la pr6xima decada. : The main discoveries performed by artificial satellites instrumented for the observation of the Sun, during the last two cycles of its activity, are described. The space observations allowed of almost all the spectral regions which are not observable from the ground, from the ultraviolet to the gamma radiation. In particular, we ref er' to the two large solar space observatories: the Skylab and the SMM. The last one included a set 0+ coordinated instruments to observe in detail the solar flares. This is a summary for astronomers not dedicated to solar physics, where we show that the of observational material have solv# d many of the preexistent problems but, at the ame time, it opened many new questions to which the improved instrumentation will try to answer. , the characteristics of the satellites planned the next decade are mentioned. Key : SUN-ACTIVITY - SUN-CORONA - SUN-X-RAYS

  16. Properties of Clay for Ceramics with Rock Waste for Production Structural Block by Pressing and Firing

    NASA Astrophysics Data System (ADS)

    Cerqueira, N. A.; Choe, D.; Alexandre, J.; Azevedo, A. R. G.; Xavier, C. G.; Souza, V. B.

    Building work requires optimization of materials and labor, so that the execution of its subsystems contribute to the quality, reduce costs, decrease waste in buildings, productivity, practicality and especially agility. Thus, the fitting blocks can contribute in this direction. This work therefore consists of physical characterization (determination of fitness levels, grain size and bulk density), chemical (EDX) and thermal (DTA and TGA) sample clay Campos dos Goytacazes-RJ and waste rock ornamental Cachoeiro de Itapemirim-ES, to verify potential for producing red ceramic blocks, pressed and burned, male and female type. The output of block will be with different pe rcentages of incorporation of residues of ornamental rocks (0%, 5% and 10%). With the results obtained, it was found that the raw materials under consideration has the potential for application in the production of ceramic articles.

  17. Research on a Denial of Service (DoS) Detection System Based on Global Interdependent Behaviors in a Sensor Network Environment

    PubMed Central

    Song, Jae-gu; Jung, Sungmo; Kim, Jong Hyun; Seo, Dong Il; Kim, Seoksoo

    2010-01-01

    This research suggests a Denial of Service (DoS) detection method based on the collection of interdependent behavior data in a sensor network environment. In order to collect the interdependent behavior data, we use a base station to analyze traffic and behaviors among nodes and introduce methods of detecting changes in the environment with precursor symptoms. The study presents a DoS Detection System based on Global Interdependent Behaviors and shows the result of detecting a sensor carrying out DoS attacks through the test-bed. PMID:22163475

  18. Calculating the trap density of states in organic field-effect transistors from experiment: A comparison of different methods

    NASA Astrophysics Data System (ADS)

    Kalb, Wolfgang L.; Batlogg, Bertram

    2010-01-01

    The spectral density of localized states in the band gap of pentacene (trap DOS) was determined with a pentacene-based thin-film transistor from measurements of the temperature dependence and gate-voltage dependence of the contact-corrected field-effect conductivity. Several analytical methods to calculate the trap DOS from the measured data were used to clarify, if the different methods lead to comparable results. We also used computer simulations to further test the results from the analytical methods. Most methods predict a trap DOS close to the valence-band edge that can be very well approximated by a single exponential function with a slope in the range of 50-60 meV and a trap density at the valence-band edge of ≈2×1021eV-1cm-3 . Interestingly, the trap DOS is always slightly steeper than exponential. An important finding is that the choice of the method to calculate the trap DOS from the measured data can have a considerable effect on the final result. We identify two specific simplifying assumptions that lead to significant errors in the trap DOS. The temperature dependence of the band mobility should generally not be neglected. Moreover, the assumption of a constant effective accumulation-layer thickness leads to a significant underestimation of the slope of the trap DOS.

  19. America Inc.: John Dos Passos'"USA" as Professional Writing Textbook.

    ERIC Educational Resources Information Center

    Di Renzo, Anthony

    While working as a special consultant for General Mills in 1948, John Dos Passos wrote a report explaining the latest scientific research and technological advancements and how the postwar economy was affecting General Mills and the cereal market. General Mills, using a real writer for a corporate freelance, profited from Dos Passos' expertise and…

  20. 76 FR 25733 - 60-Day Notice of Proposed Information Collection: DS-7001 and DS-7005, DOS-Sponsored Academic...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-05

    ... and DS- 7005, DOS-Sponsored Academic Exchange Program Application, OMB Control Number 1405-0138 ACTION... Collection: DOS-Sponsored Academic Exchange Program Application. OMB Control Number: 1405-0138. Type of... Cultural Affairs, ECA/A/E/EUR. Form Number: DS-7001, DS-7005. Respondents: Applicants for the Academic...

  1. 33 CFR 104.255 - Declaration of Security (DoS).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... and for handling DoS requests from a facility or other vessel. (b) At MARSEC Level 1, the Master or... engaging in a vessel-to-vessel activity, prior to the activity, the respective Masters, VSOs, or their... DoS for the period of the vessel-to-vessel activity. Upon the vessel-to-vessel activity and prior to...

  2. 33 CFR 104.255 - Declaration of Security (DoS).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... and for handling DoS requests from a facility or other vessel. (b) At MARSEC Level 1, the Master or... engaging in a vessel-to-vessel activity, prior to the activity, the respective Masters, VSOs, or their... DoS for the period of the vessel-to-vessel activity. Upon the vessel-to-vessel activity and prior to...

  3. Privileged structures: efficient chemical "navigators" toward unexplored biologically relevant chemical spaces.

    PubMed

    Kim, Jonghoon; Kim, Heejun; Park, Seung Bum

    2014-10-22

    In the search for new therapeutic agents for currently incurable diseases, attention has turned to traditionally "undruggable" targets, and collections of drug-like small molecules with high diversity and quality have become a prerequisite for new breakthroughs. To generate such collections, the diversity-oriented synthesis (DOS) strategy was developed, which aims to populate new chemical space with drug-like compounds containing a high degree of molecular diversity. The resulting DOS-derived libraries have been of great value for the discovery of various bioactive small molecules and therapeutic agents, and thus DOS has emerged as an essential tool in chemical biology and drug discovery. However, the key challenge has become how to design and synthesize drug-like small-molecule libraries with improved biological relevancy as well as maximum molecular diversity. This Perspective presents the development of privileged substructure-based DOS (pDOS), an efficient strategy for the construction of polyheterocyclic compound libraries with high biological relevancy. We envisioned the specific interaction of drug-like small molecules with certain biopolymers via the incorporation of privileged substructures into polyheterocyclic core skeletons. The importance of privileged substructures such as benzopyran, pyrimidine, and oxopiperazine in rigid skeletons was clearly demonstrated through the discovery of bioactive small molecules and the subsequent identification of appropriate target biomolecule using a method called "fluorescence difference in two-dimensional gel electrophoresis". Focusing on examples of pDOS-derived bioactive compounds with exceptional specificity, we discuss the capability of privileged structures to serve as chemical "navigators" toward biologically relevant chemical spaces. We also provide an outlook on chemical biology research and drug discovery using biologically relevant compound libraries constructed by pDOS, biology-oriented synthesis, or natural product-inspired DOS.

  4. Daughter of sevenless is a substrate of the phosphotyrosine phosphatase Corkscrew and functions during sevenless signaling.

    PubMed

    Herbst, R; Carroll, P M; Allard, J D; Schilling, J; Raabe, T; Simon, M A

    1996-06-14

    The SH2 domain-containing phosphotyrosine phosphatase Corkscrew (CSW) is an essential component of the signaling pathway initiated by the activation of the sevenless receptor tyrosine kinase (SEV) during Drosophila eye development. We have used genetic and biochemical approaches to identify a substrate for CSW. Expression of a catalytically inactive CSW was used to trap CSW in a complex with a 115 kDa tyrosine-phosphorylated substrate. This substrate was purified and identified as the product of the daughter of sevenless (dos) gene. Mutations of dos were identified in a screen for dominant mutations which enhance the phenotype caused by overexpression of inactive CSW during photoreceptor development. Analysis of dos mutations indicates that DOS is a positive component of the SEV signaling pathway and suggests that DOS dephosphorylation by CSW may be a key event during signaling by SEV.

  5. Polyaniline-CuO hybrid nanocomposite with enhanced electrical conductivity

    NASA Astrophysics Data System (ADS)

    de Souza, Vânia S.; da Frota, Hidembergue O.; Sanches, Edgar A.

    2018-02-01

    A hybrid nanocomposite based on a polymer matrix constituted of Polyaniline Emeraldine-salt form (PANI-ES) reinforced by copper oxide II (CuO) particles was obtained by in situ polymerization. Structural, morphological and electrical properties of the pure materials and nanocomposite form were investigated. The presence of CuO particles in the nanocomposite material affected the natural alignment of the polymer chains. XRD technique allowed the visualization of the polymer amorphization in the nanocomposite form, suggesting an interaction between both phases. The FTIR spectra confirmed this molecular interaction due to the blue shift of the characteristic absorption peaks of PANI-ES in the nanocomposite form. SEM images revealed that the polymer nanofiber morphology was no longer observed in the nanocomposite. The CuO spherical particles are randomly dispersed in the polymer matrix. The density functional theory plus the Coulomb interaction method revealed a charge transfer from PANI to CuO slab. Moreover, the density of states (DOS) has revealed that the nanocomposite behaves as a metal. In agreement, the electrical conductivity showed an increase of 60% in the nanocomposite material.

  6. Graphene/blue-phosphorus heterostructure as potential anode materials for sodium-ion batteries

    NASA Astrophysics Data System (ADS)

    Fan, Kaimin; Tang, Ting; Wu, Shiyun; Zhang, Zhiyuan

    2018-01-01

    The first-principles calculations based on density functional theory (DFT) have been implemented to investigate the graphene/blue-phosphorus (G/BP) heterostructure as potential anode material for SIBs. The adsorption and diffusion behaviors of sodium (Na) in G/BP heterostructure and the effect of external electric field on Na adsorption have been investigated. The results indicate that G/BP heterostructure with Na adsorption is metallic due to Na incorporation, which is of benefit for electronic conductivity as anode material. The results show that the design of G/BP heterostructure is an efficient scheme to enhance the Na adsorption in G/BP without affecting the high mobility of Na in the G/BP heterostructure surface. The present work demonstrates that the external electric field can effectively modulate the adsorption of Na, and the adsorption behavior of Na is more sensitive to the external electric field when E > 0.10 V Å-1 in G/BP heterostructure. The Mulliken population analysis and DOS calculations have been performed to explore the charge transfer and the interaction between Na and G/BP.

  7. Hydrogen adsorption in metal-decorated silicon carbide nanotubes

    NASA Astrophysics Data System (ADS)

    Singh, Ram Sevak; Solanki, Ankit

    2016-09-01

    Hydrogen storage for fuel cell is an active area of research and appropriate materials with excellent hydrogen adsorption properties are highly demanded. Nanotubes, having high surface to volume ratio, are promising storage materials for hydrogen. Recently, silicon carbide nanotubes have been predicted as potential materials for future hydrogen storage application, and studies in this area are ongoing. Here, we report a systematic study on hydrogen adsorption properties in metal (Pt, Ni and Al) decorated silicon carbide nanotubes (SiCNTs) using first principles calculations based on density functional theory. The hydrogen adsorption properties are investigated by calculations of adsorption energy, electronic band structure, density of states (DOS) and Mulliken charge population analysis. Our findings show that hydrogen adsorptions on Pt, Ni and Al-decorated SiCNTs undergo spontaneous exothermic reactions with significant modulation of electronic structure of SiCNTs in all cases. Importantly, according to the Mulliken charge population analysis, dipole-dipole interaction causes chemisorptions of hydrogen in Pt, Ni and Al decorated SiCNTs with formation of chemical bonds. The study is a platform for the development of metal decorated SiCNTs for hydrogen adsorption or hydrogen storage application.

  8. Theoretical Study of Gilbert Damping and Spin Dynamics in Spintronic Devices

    NASA Astrophysics Data System (ADS)

    Qu, Tao

    The determination of damping mechanisms is one of the most fundamental problems of magnetism. It represents the elimination of the magnetic energy and thus has broad impact in both science and technology. The dynamic time scale in spintronic devices is controlled by the damping and the consumed power depends on the damping constant squared. In recent years, the interest in high perpendicular anisotropy materials and thin film structures have increased considerably, owing to their stability over a wide temperature range when scaling devices to nanometer length scales. However, the conventional measurement method-Ferromagnetic resonance (FMR) can not produce accurate damping results in the high magnetic crystalline anisotropy materials/structures, and the intrinsic damping reported experimentally diverges among investigators, probably due to the varying fabrication techniques. This thesis describes the application of the Kambersky torque correlation technique, within the tight binding method, to multiple materials with high perpendicular magnetic anisotropy ( 10 7 erg/cm3), in both bulk and thin film structures. The impact of the inevitable experimental defects on the energy dissipation is identified and the experimental damping divergence among investigators due to the material degree of order is explained. It is demonstrated that this corresponds to an enhanced DOS at the Fermi level, owing to the rounding of the DOS with loss of long-range order. The consistency of the predicted damping constant with experimental measurement is demonstrated and the interface contribution to the energy damping constant in potential superlattices and heterostructures for spintronic devices is explored. An optimized structure will be a tradeoff involving both anisotropy and damping. The damping related spin dynamics in spintronic devices for different applications is investigated. One device is current perpendicular to planes(CPP) spin valve. Incoherent scattering matrices are applied to calculate the angle dependent magnetoresistantce and obtain analytic expressions for the spin valve. The non-linearity of magnetoresistance can be quantitatively explained by reflected electrons using only experimental spin polarization as input. The other device is a spin-transfer-torque nano-oscillator. The Landau-Lifshitz-Gilbert equation is applied and the synchronization requirement for experimentally fabricated non-identical multi spintronic oscillators is explored. Power enhancement and noise decrease for the synchronized state is demonstrated in a temperature range. Through introducing combined electric and magnetic coupling effect, a design for an optimized feasible nanopillar structure suitable for thin-film deposition is developed.

  9. Non-invasive tissue temperature measurements based on quantitative diffuse optical spectroscopy (DOS) of water.

    PubMed

    Chung, S H; Cerussi, A E; Merritt, S I; Ruth, J; Tromberg, B J

    2010-07-07

    We describe the development of a non-invasive method for quantitative tissue temperature measurements using Broadband diffuse optical spectroscopy (DOS). Our approach is based on well-characterized opposing shifts in near-infrared (NIR) water absorption spectra that appear with temperature and macromolecular binding state. Unlike conventional reflectance methods, DOS is used to generate scattering-corrected tissue water absorption spectra. This allows us to separate the macromolecular bound water contribution from the thermally induced spectral shift using the temperature isosbestic point at 996 nm. The method was validated in intralipid tissue phantoms by correlating DOS with thermistor measurements (R=0.96) with a difference of 1.1+/-0.91 degrees C over a range of 28-48 degrees C. Once validated, thermal and hemodynamic (i.e. oxy- and deoxy-hemoglobin concentration) changes were measured simultaneously and continuously in human subjects (forearm) during mild cold stress. DOS-measured arm temperatures were consistent with previously reported invasive deep tissue temperature studies. These results suggest that DOS can be used for non-invasive, co-registered measurements of absolute temperature and hemoglobin parameters in thick tissues, a potentially important approach for optimizing thermal diagnostics and therapeutics.

  10. Effective tobacco control measures: agreement among medical students.

    PubMed

    Martins, Stella Regina; Paceli, Renato Batista; Bussacos, Marco Antônio; Fernandes, Frederico Leon Arrabal; Prado, Gustavo Faibischew; Lombardi, Elisa Maria Siqueira; Terra-Filho, Mário; Santos, Ubiratan Paula

    2017-01-01

    To determine the level of agreement with effective tobacco control measures recommended by the World Health Organization and to assess the attitudes toward, knowledge of, and beliefs regarding smoking among third-year medical students at University of São Paulo School of Medicine, located in the city of São Paulo, Brazil. Between 2008 and 2012, all third-year medical students were invited to complete a self-administered questionnaire based on the Global Health Professionals Student Survey and its additional modules. The study sample comprised 556 students. The level of agreement with the World Health Organization recommendations was high, except for the components "received smoking cessation training" and "raising taxes is effective to reduce the prevalence of smoking". Most of the students reported that they agree with banning tobacco product sales to minors (95%), believe that physicians are role models to their patients (84%), and believe that they should advise their patients to quit cigarette smoking (96%) and using other tobacco products (94%). Regarding smoking cessation methods, most of the students were found to know more about nicotine replacement therapy than about non-nicotine therapies (93% vs. 53%). Only 37% of the respondents were aware of the importance of educational antismoking materials, and only 31% reported that they believe in the effectiveness of encouraging their patients, during medical visits. In our sample, the prevalence of current cigarette smoking was 5.23%; however, 43.82% of the respondents reported having experimented with water-pipe tobacco smoking. Our results revealed the need to emphasize to third-year medical students the importance of raising the prices of and taxes on tobacco products. We also need to make students aware of the dangers of experimenting with tobacco products other than cigarettes, particularly water-pipe tobacco smoking. Determinar o grau de concordância com medidas eficazes de controle do tabaco recomendadas pela Organização Mundial da Saúde e avaliar as atitudes, o conhecimento e as crenças a respeito do tabagismo em alunos do terceiro ano de medicina da Faculdade de Medicina da Universidade de São Paulo, em São Paulo (SP). Entre 2008 e 2012, todos os alunos do terceiro ano de medicina foram convidados a preencher um questionário autoaplicável baseado na Global Health Professions Student Survey e em seus módulos adicionais. A amostra consistiu em 556 estudantes. O grau de concordância com as recomendações da Organização Mundial da Saúde foi alto, à exceção de "receberam treinamento a respeito de cessação do tabagismo" e "aumentar os impostos é uma medida eficaz para reduzir a prevalência do tabagismo". A maioria dos estudantes relatou que concorda com a proibição da venda de produtos do tabaco a menores de idade (95%), acredita que os médicos são modelos de comportamento para seus pacientes (84%) e acredita que deveriam aconselhar seus pacientes a parar de fumar cigarros (96%) e de usar outros produtos do tabaco (94%). No tocante aos métodos de cessação do tabagismo, observamos que a maioria dos estudantes sabe mais sobre terapia de reposição da nicotina do que sobre terapias não nicotínicas (93% vs. 53%). Apenas 37% dos participantes estavam cientes da importância de material educacional antitabagismo, e apenas 31% relataram que acreditam na eficácia de incentivar seus pacientes, durante as consultas médicas, a parar de fumar. Em nossa amostra, a prevalência de tabagismo atual foi de 5,23%; entretanto, 43,82% dos participantes relataram ter experimentado fumar tabaco com um narguilé. Nossos resultados revelaram a necessidade de deixar claro para os alunos do terceiro ano de medicina o quão importante é aumentar os preços e impostos dos produtos do tabaco. É também preciso conscientizar os alunos dos perigos de experimentar outros produtos do tabaco que não os cigarros, particularmente o narguilé.

  11. Comment on “Dissolved organic sulfur in the ocean: Biogeochemistry of a petagram inventory”

    NASA Astrophysics Data System (ADS)

    Dittmar, Thorsten; Stubbins, Aron; Ito, Takamitsu; Jones, Daniel C.

    2017-05-01

    Ksionzek et al. (Reports, 28 October 2016, p. 456) provide important data describing the distribution of dissolved organic sulfur (DOS) in the Atlantic Ocean. Here, we show that mixing between water masses is sufficient to explain the observed distribution of DOS, concluding that the turnover time of refractory DOS that Ksionzek et al. present cannot be deduced from their data.

  12. DataPlus™ - a revolutionary applications generator for DOS hand-held computers

    Treesearch

    David Dean; Linda Dean

    2000-01-01

    DataPlus allows the user to easily design data collection templates for DOS-based hand-held computers that mimic clipboard data sheets. The user designs and tests the application on the desktop PC and then transfers it to a DOS field computer. Other features include: error checking, missing data checks, and sensor input from RS-232 devices such as bar code wands,...

  13. 76 FR 59240 - Airworthiness Directives; Empresa Brasileira de Aeronáutica S.A. (EMBRAER) Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-26

    ... Support, Av. Brig. Faria Lima, 2170, Sao Jose dos Campos-SP, CEP: 12227-901--PO Box: 36/2, Brasil.... Brig. Faria Lima, 2170, Sao Jose dos Campos--SP, CEP: 12227-901--PO Box: 36/2, Brasil; telephone: ++55... dos Campos--SP, CEP: 12227-901--PO Box: 36/2, Brasil; telephone: ++55 12 3927-5383; fax: ++55 12 3927...

  14. 48 CFR 653.219-70 - DOS form DS-1910, Small Business Agency Review-Actions Above the Simplified Acquisition Threshold.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false DOS form DS-1910, Small Business Agency Review-Actions Above the Simplified Acquisition Threshold. 653.219-70 Section 653.219-70 Federal Acquisition Regulations System DEPARTMENT OF STATE CLAUSES AND FORMS FORMS Prescription of Forms 653.219-70 DOS form DS-1910, Small...

  15. 48 CFR 653.219-70 - DOS form DS-1910, Small Business Agency Review-Actions Above the Simplified Acquisition Threshold.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 4 2011-10-01 2011-10-01 false DOS form DS-1910, Small Business Agency Review-Actions Above the Simplified Acquisition Threshold. 653.219-70 Section 653.219-70 Federal Acquisition Regulations System DEPARTMENT OF STATE CLAUSES AND FORMS FORMS Prescription of Forms 653.219-70 DOS form DS-1910, Small...

  16. 48 CFR 653.219-70 - DOS form DS-1910, Small Business Agency Review-Actions Above the Simplified Acquisition Threshold.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 4 2014-10-01 2014-10-01 false DOS form DS-1910, Small Business Agency Review-Actions Above the Simplified Acquisition Threshold. 653.219-70 Section 653.219-70 Federal Acquisition Regulations System DEPARTMENT OF STATE CLAUSES AND FORMS FORMS Prescription of Forms 653.219-70 DOS form DS-1910, Small...

  17. 48 CFR 653.219-70 - DOS form DS-1910, Small Business Agency Review-Actions Above the Simplified Acquisition Threshold.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 4 2013-10-01 2013-10-01 false DOS form DS-1910, Small Business Agency Review-Actions Above the Simplified Acquisition Threshold. 653.219-70 Section 653.219-70 Federal Acquisition Regulations System DEPARTMENT OF STATE CLAUSES AND FORMS FORMS Prescription of Forms 653.219-70 DOS form DS-1910, Small...

  18. Derivatization and diffusive motion of molecular fullerenes: Ab initio and atomistic simulations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Berdiyorov, G., E-mail: gberdiyorov@qf.org.qa; Tabet, N.; Harrabi, K.

    2015-07-14

    Using first principles density functional theory in combination with the nonequilibrium Green's function formalism, we study the effect of derivatization on the electronic and transport properties of C{sub 60} fullerene. As a typical example, we consider [6,6]-phenyl-C{sub 61}-butyric acid methyl ester (PCBM), which forms one of the most efficient organic photovoltaic materials in combination with electron donating polymers. Extra peaks are observed in the density of states (DOS) due to the formation of new electronic states localized at/near the attached molecule. Despite such peculiar behavior in the DOS of an isolated molecule, derivatization does not have a pronounced effect onmore » the electronic transport properties of the fullerene molecular junctions. Both C{sub 60} and PCBM show the same response to finite voltage biasing with new features in the transmission spectrum due to voltage induced delocalization of some electronic states. We also study the diffusive motion of molecular fullerenes in ethanol solvent and inside poly(3-hexylthiophene) lamella using reactive molecular dynamics simulations. We found that the mobility of the fullerene reduces considerably due to derivatization; the diffusion coefficient of C{sub 60} is an order of magnitude larger than the one for PCBM.« less

  19. Semiconducting molecular crystals: Bulk in-gap states modified by structural and chemical defects

    NASA Astrophysics Data System (ADS)

    Haas, S.; Krellner, C.; Goldmann, C.; Pernstich, K. P.; Gundlach, D. J.; Batlogg, B.

    2007-03-01

    Charge transport in organic molecular crystals is strongly influenced by the density of localized in-gap states (traps). Thus, a profound knowledge of the defect states' origin is essential. Temperature-dependent space-charge limited current (TD-SCLC) spectroscopy was used as a powerful tool to quantitatively study the density of states (DOS) in high-quality rubrene and pentacene single crystals. In particular, changes of the DOS due to intentionally induced chemical and structural defects were monitored. For instance, the controlled exposure of pentacene and rubrene to x-ray radiation results in a broad over-all increase of the DOS. Namely, the ionizing radiation induces a variety of both chemical and structural defects. On the other hand, exposure of rubrene to UV-excited oxygen is reflected in a sharp peak in the DOS, whereas in a similar experiment with pentacene oxygen acts as a dopant, and possible defects are metastable on the time-scale of the measurement, thus leaving the extracted DOS virtually unchanged.

  20. Death obsession in Palestinians.

    PubMed

    Abdel-Khalek, Ahmed M; Al-Arja, Nahida S; Abdalla, Taysir

    2006-04-01

    The authors explored death obsession level and correlates among a sample (N = 601) of Palestinians living in the city of Beit Jala, the village of Al-Khader, and the Aida refugee camp in the Bethlehem area. They live in war conditions; the houses of half of them have been demolished. The Death Obsession Scale (DOS) was administered. Its alpha reliability was .92, denoting high internal consistency. Among women, it yielded 1 factor, (General Death Obsession), whereas among men it yielded 3 factors: Death Rumination, Death Dominance, and Death Idea Repetition. Palestinian men and women attained significantly lower DOS mean scores than participants from 4 Arab countries: Egypt, Kuwait, Syria, and Lebanon in 7 out of 8 comparisons. However, Palestinian women had significantly higher DOS mean score than their Spanish, American and British counterparts, whereas Palestinian men had significantly higher mean DOS score than Spanish peers. The low DOS scores of Palestinians, in proportion to other Arab samples, may reflect their adaptation to strife and violence.

  1. Aging Degradation of Austenitic Stainless Steel Weld Probed by Electrochemical Method and Impact Toughness Evaluation

    NASA Astrophysics Data System (ADS)

    Singh, Raghuvir; Das, Goutam; Mahato, B.; Singh, P. K.

    2017-03-01

    The present study discriminates the spinodal decomposition and G-phase precipitation in stainless steel welds by double loop electrochemical potentio-kinetic reactivation method and correlates it with the degradation in toughness property. The welds produced with different heat inputs were aged up to 10,000 hours at 673 K to 723 K (400 to 450 °C) and evaluated subsequently for the degree of sensitization (DOS) and impact toughness. The DOS values obtained were attributed to the spinodal decomposition and precipitation of G-phase. Study shows that the DOS correlates well with the impact toughness of the 304LN weld. Prolonged aging at 673 K and 723 K (400 °C and 450 °C) increased the DOS values while the impact toughness was decreased. The weld fabricated at 1 kJ/mm of heat input, produced higher DOS, compared to that at 3 kJ/mm. The geometrical location along the weld is shown to influence the DOS; higher values were obtained at the root than at the topside of the weld. Vermicular and columnar microstructure, in addition to the spinodal decomposition and G-phase precipitation, observed in the root side of the weld appear risky for the impact toughness.

  2. pH dependence of cyanide binding to the ferric heme domain of the direct oxygen sensor from Escherichia coli and the effect of alkaline denaturation.

    PubMed

    Bidwai, Anil K; Ok, Esther Y; Erman, James E

    2008-09-30

    The spectrum of the ferric heme domain of the direct oxygen sensor protein from Escherichia coli ( EcDosH) has been measured between pH 3.0 and 12.6. EcDosH undergoes acid denaturation with an apparent p K a of 4.24 +/- 0.05 and a Hill coefficient of 3.1 +/- 0.6 and reversible alkaline denaturation with a p K a of 9.86 +/- 0.04 and a Hill coefficient of 1.1 +/- 0.1. Cyanide binding to EcDosH has been investigated between pH 4 and 11. The EcDosH-cyanide complex is most stable at pH 9 with a K D of 0.29 +/- 0.06 microM. The kinetics of cyanide binding are monophasic between pH 4 and 8. At pH >or=8.5, the reaction is biphasic with the fast phase dependent upon the cyanide concentration and the slow phase independent of cyanide. The slow phase is attributed to conversion of denatured EcDosH to the native state, with a pH-independent rate of 0.052 +/- 0.006 s (-1). The apparent association rate constant for cyanide binding to EcDosH increases from 3.6 +/- 0.1 M (-1) s (-1) at pH 4 to 520 +/- 20 M (-1) s (-1) at pH 11. The dissociation rate constant averages (8.6 +/- 1.3) x 10 (-5) s (-1) between pH 5 and 9, increasing to (1.4 +/- 0.1) x 10 (-3) s (-1) at pH 4 and (2.5 +/- 0.1) x 10 (-3) s (-1) at pH 12.2. The mechanism of cyanide binding is consistent with preferential binding of the cyanide anion to native EcDosH. The reactions of imidazole and H 2O 2 with ferric EcDosH were also investigated and show little reactivity.

  3. Izabel dos Santos and the training of the health workers.

    PubMed

    Paiva, Carlos Henrique Assunção

    2015-06-01

    This article discusses the career of Izabel dos Santos (1927-2010) as a means of examining the connections between health schools and agendas in contemporary Brazil. The article highlights dos Santos's training and her work in the Serviço Especial de Saúde Pública (SESP- Special Public Health Service), the Pan American Health Organization (PAHO) and in the formulation and implementation of national training programs for human resources within the area of health from the late 1970s onwards. The article highlights dos Santos's central role in the formulation and implementation of training policies for health workers, especially nursing technicians and assistants, and demonstrates how she occupies an important place in the history of Brazilian public health.

  4. Unraveling surface and bulk trap states in lead halide perovskite solar cells using impedance spectroscopy

    NASA Astrophysics Data System (ADS)

    Han, Changfeng; Wang, Kai; Zhu, Xixiang; Yu, Haomiao; Sun, Xiaojuan; Yang, Qin; Hu, Bin

    2018-03-01

    Organic-inorganic hybrid perovskites (OIHPs) have been widely recognized as an excellent candidate for next-generation photovoltaic materials because of their highly efficient power conversion. Acquiring a complete understanding of trap states and dielectric properties in OIHP-based solar cells at the steady state is highly desirable in order to further explore and improve their optoelectronic functionalities and properties. We report CH3NH3PbI3-x Cl x -based planar solar cells with a power conversion efficiency (PCE) of 15.8%. The illumination intensity dependence of the current density-voltage (J-V) revealed the presence of trap-assisted recombination at low fluences. Non-destructive ac impedance spectroscopy (ac-IS) was applied to characterize the device at the steady state. The capacitance-voltage (C-V) spectra exhibited some distinct variations at a wide range of ac modulation frequencies with and without photo-excitations. Since the frequency-dependent chemical capacitance ({{C}μ }) is concerned with the surface and bulk related density of states (DOS) in CH3NH3PbI3-x Cl x , we verified this by fitting the corresponding DOS by a Gaussian distribution function. We ascertained that the electronic sub-gap trap states present in the solution processed CH3NH3PbI3-x Cl x and their distribution differs from the surface to the bulk. In fact, we demonstrated that both surfaces that were adjacent to the electron and hole transport layers featured analogous DOS. Despite this, photo- and bias-induced giant dielectric responses (i.e. both real and imaginary parts) were detected. A remarkable reduction of {{C}μ } at higher frequencies (i.e. more than 100 kHz) was ascribed to the effect of dielectric loss in CH3NH3PbI3-x Cl x .

  5. Documenting 35 years of land cover change: Lago Cachet Dos drainage, Chile

    USGS Publications Warehouse

    Friesen, Beverly A.; Nimick, David A.; Mcgrath, Daniel; Cole, Christopher J.; Wilson, Earl M.; Noble, Suzanne M.; Fahey, Mark J.; Leidich, Jonathan; O'Kuinghttons Villena, Jorge I.

    2015-01-01

    The U.S. Geological Survey (USGS) Special Applications Science Center is monitoring temporal changes at the Colonia Glacier and Lago Cachet Dos, Northern Patagonia Icefield of southern Chile. This location is one of the newest international sites in the USGS Global Fiducial Program (GFP)—a program which provides systematic monitoring of dynamic and environmentally critical areas with high-resolution imagery (http://gfp.usgs.gov/). In 2008, Lago Cachet Dos began experiencing glacial lake outburst floods (GLOFs) during which the entire pool of water (about 200 million cubic meters) rapidly drains from the lake and flows south-southeast through the Colonia Glacier. These catastrophic events cause massive erosion of valley-fill deposits and consequent upstream expansion of Lago Cachet Dos towards Lago Cachet Uno.  Panchromatic and multispectral images for 1979, 2007, and 2014 highlight the dramatic changes that have occurred at this site over a 35-year period. The lake was smallest in 1979, when the Colonia Glacier was at its maximum extent during the study period. Between 1979 and 2007, the glacier shrank causing an increase in the surface area of the lake. The size of the lake increased substantially, from 2.98 square kilometers (km2) in 1979 to 4.41 km2 in 2014, primarily due to erosion of valley-fill deposits upstream of its northern edge by the 15 GLOFs that occurred between April 2008 and February 2014. Ongoing studies of the Colonia Glacier and Lago Cachet Dos are focused on providing real-time monitoring of Lago Cachet Dos lake levels, understanding the history of advances and retreats of the Colonia Glacier, and determining the physical mechanisms and hazards associated with the GLOFs that come from Lago Cachet Dos.

  6. A hybrid protection approaches for denial of service (DoS) attacks in wireless sensor networks

    NASA Astrophysics Data System (ADS)

    Gunasekaran, Mahalakshmi; Periakaruppan, Subathra

    2017-06-01

    Wireless sensor network (WSN) contains the distributed autonomous devices with the sensing capability of physical and environmental conditions. During the clustering operation, the consumption of more energy causes the draining in battery power that leads to minimum network lifetime. Hence, the WSN devices are initially operated on low-power sleep mode to maximise the lifetime. But, the attacks arrival cause the disruption in low-power operating called denial of service (DoS) attacks. The conventional intrusion detection (ID) approaches such as rule-based and anomaly-based methods effectively detect the DoS attacks. But, the energy consumption and false detection rate are more. The absence of attack information and broadcast of its impact to the other cluster head (CH) leads to easy DoS attacks arrival. This article combines the isolation and routing tables to detect the attack in the specific cluster and broadcasts the information to other CH. The intercommunication between the CHs prevents the DoS attacks effectively. In addition, the swarm-based defence approach is proposed to migrate the fault channel to normal operating channel through frequency hop approaches. The comparative analysis between the proposed table-based intrusion detection systems (IDSs) and swarm-based defence approaches with the traditional IDS regarding the parameters of transmission overhead/efficiency, energy consumption, and false positive/negative rates proves the capability of DoS prediction/prevention in WSN.

  7. SH3 domain-mediated binding of the Drk protein to Dos is an important step in signaling of Drosophila receptor tyrosine kinases.

    PubMed

    Feller, Stephan M; Wecklein, Heike; Lewitzky, Marc; Kibler, Eike; Raabe, Thomas

    2002-08-01

    Activation of the Sevenless (Sev) receptor tyrosine kinase (RTK) in the developing Drosophila eye is required for the specification of the R7 photoreceptor cell fate. Daughter of Sevenless (Dos), a putative multi-site adaptor protein, is a substrate of the Sev kinase and is known to associate with the tyrosine phosphatase Corkscrew (Csw). Binding of Csw to Dos depends on the Csw Src homology 2 (SH2) domains and is an essential step for signaling by the Sev RTK. Dos, however, lacks a recognizable phosphotyrosine interaction domain and it was previously unclear how it is recruited to the Sev receptor. Here it is shown that the SH2/SH3 domain adaptor protein Drk can provide this link. Drk binds with its SH2 domain to the autophosphorylated Sev receptor while the C-terminal SH3 domain is able to associate with Dos. The Drk SH3 domain binding motifs on Dos were mapped to two sites which do not conform the known Drk SH3 domain binding motif (PxxPxR) but instead have the consensus PxxxRxxKP. Mutational analysis in vitro and in vivo provided evidence that both Drk binding sites fulfil an important function in the context of Sev and Drosophila epidermal growth factor receptor mediated signaling processes.

  8. Are All-Solid-State Lithium-Ion Batteries Really Safe?-Verification by Differential Scanning Calorimetry with an All-Inclusive Microcell.

    PubMed

    Inoue, Takao; Mukai, Kazuhiko

    2017-01-18

    Although all-solid-state lithium-ion batteries (ALIBs) have been believed as the ultimate safe battery, their true character has been an enigma so far. In this paper, we developed an all-inclusive-microcell (AIM) for differential scanning calorimetry (DSC) analysis to clarify the degree of safety (DOS) of ALIBs. Here AIM possesses all the battery components to work as a battery by itself, and DOS is determined by the total heat generation ratio (ΔH) of ALIB compared with the conventional LIB. When DOS = 100%, the safety of ALIB is exactly the same as that of LIB; when DOS = 0%, ALIB reaches the ultimate safety. We investigated two types of LIB-AIM and three types of ALIB-AIM. Surprisingly, all the ALIBs exhibit one or two exothermic peaks above 250 °C with 20-30% of DOS. The exothermic peak is attributed to the reaction between the released oxygen from the positive electrode and the Li metal in the negative electrode. Hence, ALIBs are found to be flammable as in the case of LIBs. We also attempted to improve the safety of ALIBs and succeeded in decreasing the DOS down to ∼16% by incorporating Ketjenblack into the positive electrode as an oxygen scavenger. Based on ΔH as a function of voltage window, a safety map for LIBs and ALIBs is proposed.

  9. Superconductivity in Bismuth. A New Look at an Old Problem.

    PubMed

    Mata-Pinzón, Zaahel; Valladares, Ariel A; Valladares, Renela M; Valladares, Alexander

    2016-01-01

    To investigate the relationship between atomic topology, vibrational and electronic properties and superconductivity of bismuth, a 216-atom amorphous structure (a-Bi216) was computer-generated using our undermelt-quench approach. Its pair distribution function compares well with experiment. The calculated electronic and vibrational densities of states (eDOS and vDOS, respectively) show that the amorphous eDOS is about 4 times the crystalline at the Fermi energy, whereas for the vDOS the energy range of the amorphous is roughly the same as the crystalline but the shapes are quite different. A simple BCS estimate of the possible crystalline superconducting transition temperature gives an upper limit of 1.3 mK. The e-ph coupling is more preponderant in a-Bi than in crystalline bismuth (x-Bi) as indicated by the λ obtained via McMillan's formula, λc = 0.24 and experiment λa = 2.46. Therefore with respect to x-Bi, superconductivity in a-Bi is enhanced by the higher values of λ and of eDOS at the Fermi energy.

  10. Superconductivity in Bismuth. A New Look at an Old Problem

    PubMed Central

    2016-01-01

    To investigate the relationship between atomic topology, vibrational and electronic properties and superconductivity of bismuth, a 216-atom amorphous structure (a-Bi216) was computer-generated using our undermelt-quench approach. Its pair distribution function compares well with experiment. The calculated electronic and vibrational densities of states (eDOS and vDOS, respectively) show that the amorphous eDOS is about 4 times the crystalline at the Fermi energy, whereas for the vDOS the energy range of the amorphous is roughly the same as the crystalline but the shapes are quite different. A simple BCS estimate of the possible crystalline superconducting transition temperature gives an upper limit of 1.3 mK. The e-ph coupling is more preponderant in a-Bi than in crystalline bismuth (x-Bi) as indicated by the λ obtained via McMillan’s formula, λc = 0.24 and experiment λa = 2.46. Therefore with respect to x-Bi, superconductivity in a-Bi is enhanced by the higher values of λ and of eDOS at the Fermi energy. PMID:26815431

  11. Cleaning Genesis Solar Wind Collectors with Ultrapure Water: Residual Contaminant Particle Analysis

    NASA Technical Reports Server (NTRS)

    Allton, J. H.; Wentworth, S. J.; Rodriquez, M. C.; Calaway, M. J.

    2008-01-01

    Additional experience has been gained in removing contaminant particles from the surface of Genesis solar wind collectors fragments by using megasonically activated ultrapure water (UPW)[1]. The curatorial facility has cleaned six of the eight array collector material types to date: silicon (Si), sapphire (SAP), silicon-on-sapphire (SOS), diamond-like carbon-on-silicon (DOS), gold-on-sapphire (AuOS), and germanium (Ge). Here we make estimates of cleaning effectiveness using image analysis of particle size distributions and an SEM/EDS reconnaissance of particle chemistry on the surface of UPW-cleaned silicon fragments (Fig. 1). Other particle removal techniques are reported by [2] and initial assessment of molecular film removal is reported by [3].

  12. High quality crystalline pentacene and rubrene FETs

    NASA Astrophysics Data System (ADS)

    Butko, Vladimir

    2005-03-01

    Molecular organic materials offer the promise of novel electronic devices but also present challenges for understanding charge transport in narrow band systems. We find that one of the most important intermolecular transport FET parameters, the effective channel mobility, is parameterized by two factors: (1) the degree of carrier trapping in localized DOS band-tail states, which are higher in concentration for FET structures than for bulk crystal, and (2) the free-carrier mobility, μ0. Our analysis shows crystalline devices possess μ0˜70 cm^2/Vs, significantly greater than polycrystalline thin film devices where free-carrier mobility μ0˜1 cm^2/Vs. Low temperature studies elucidate fundamental transport processes. We report the lowest temperature field effect transport results on a crystalline oligomeric organic material, rubrene. Gated transport shows a factor of ˜10 suppression of the thermal activation energy in 10-50 K range and nearly temperature independent resistivity below 10 K. Other examples of 2 dimensional charge carrier transport will also be discussed.

  13. The Brazilian Malaria Vector Anopheles (Kerteszia) Cruzii: Life Stages and Biology (Diptera: Culicidae)

    DTIC Science & Technology

    1991-11-01

    Mosquitos no litoral paranaense. I - Idade fisioldgica de no Parque National da Serra dos Orgaos, Anopheles cruzii (Diptera, Culicidae). Arq. Estado do...no Parque National da Peryassii, A.G. 1908. OS culicideos do Brazil. Serra dos Grgaos, Estado do Rio de Janeiro, Inst. de Manguinhos, Rio de Janeiro...Kerteszia no litoral Guimar%es, A.E. and V.N.M. Victoria. 1986. do estado de Santa Catarina. Rev. Bras. Mosquitos no Parque National da Serra dos

  14. Development of Less Toxic Treatment Strategies for Metastatic and Drug-Resistant Breast Cancer Using Noninvasive Optical Monitoring

    DTIC Science & Technology

    2017-09-01

    models has been evaluated, with one good option, the Py230 cell lines, as our choice for use in future studies . We have conducted the first study ... Study of Progressive Resistance Major Task 6: dDOS fabrication Subtask 15: Design /Fabricate dDOS system and new custom dDOS probe 6-24 Dr...until year 3 of the study , based on current accrual trends with our clinical collaborators at the Boston Medical Center for different projects, the

  15. Sedimentation History of Lago Dos Bocas, Puerto Rico, 1942-2005

    USGS Publications Warehouse

    Soler-López, Luis R.

    2007-01-01

    The Lago Dos Bocas Dam, located in the municipality of Utuado in north central Puerto Rico, was constructed in 1942 for hydroelectric power generation. The reservoir had an original storage capacity of 37.50 million cubic meters and a drainage area of 440 square kilometers. In 1948, the construction of the Lago Caonillas Dam on the Rio Caonillas branch of Lago Dos Bocas reduced the natural sediment-contributing drainage area to 310 square kilometers; therefore, the Lago Caonillas Dam is considered an effective sediment trap. Sedimentation in Lago Dos Bocas reservoir has reduced the storage capacity from 37.50 million cubic meters in 1942 to 17.26 million cubic meters in 2005, which represents a storage loss of about 54 percent. The long-term annual water-storage capacity loss rate remained nearly constant at about 320,000 cubic meters per year to about 1997. The inter-survey sedimentation rate between 1997 and 1999, however, is higher than the long-term rate at about 1.09 million cubic meters per year. Between 1999 and 2005 the rate is lower than the long-term rate at about 0.13 million cubic meters per year. The Lago Dos Bocas effective sediment-contributing drainage area had an average sediment yield of about 1,400 cubic meters per square kilometer per year between 1942 and 1997. This rate increased substantially by 1999 to about 4,600 cubic meters per square kilometer per year, probably resulting from the historical magnitude floods caused by Hurricane Georges in 1998. Recent data indicate that the Lago Dos Bocas drainage area sediment yield decreased substantially to about 570 cubic meters per square kilometer per year, which is much lower than the 1942-1997 area normalized sedimentation rate of 1,235 cubic meters per square kilometer per year. The impact of Hurricane Georges on the basin sediment yield could have been the cause of this change, since the magnitude of the floods could have nearly depleted the Lago Dos Bocas drainage area of easily erodible and transportable bed sediment. This report summarizes the historical change in water-storage capacity of Lago Dos Bocas between 1942 and 2005.

  16. Combination of broadband diffuse optical spectroscopy with magnetic resonance imaging

    NASA Astrophysics Data System (ADS)

    Merritt, Sean Isaiah

    Broadband diffuse optical spectroscopy (DOS) is an emerging optical technique used to measure absorption and scattering of bulk tissue non-invasively within the near-infrared (600--1050 nm). The ultimate aim of my advisors group is for broadband DOS to become an established medical diagnostic technique used clinically on various tissue types including breast, muscle and bone. The specific goal for my research is to use established magnetic resonance (MR) techniques for the purpose of continued development and validation of broadband DOS. The initial studies carried out were a validation of broadband DOS through a direct comparison with MRI. Both techniques are sensitive to signals produced by water and lipids in tissue. There is also sensitivity to blood flow, which MRI measures using exogenous contrast agents and broadband DOS is sensitive through measurement of total hemoglobin content (THC) and tissue oxygen saturation (StO2). These validation studies were compared initially in a rat tumor model in which both techniques were used simultaneously. A qualitative correlation was found between the MR images of water content and blood perfusion compared with the DOS water and THC values. A more quantitative comparison was made between measuring absolute water and lipid content in phantoms and in human tissue, which showed a strong correlation. The in vivo study also validated that broadband DOS was interrogating bone marrow in the tibia. The second half of this thesis is focused on developing new capabilities of broadband DOS and the MRI literature is used as a guide. When a water molecule hydrogen bonds to another molecule, the absorption spectrum in the near-infrared which is due to the vibrational overtone of the OH bond will change. The expected changes were observed in tissue and an algorithm was developed to fit for a tissue bound water parameter. Also, as tissue temperature changes, the fraction of water bound to other water molecules changes and can be used to fit for deep tissue temperature. Preliminary validation of these two techniques is carried out and there appears to be great potential for these methods.

  17. Improved p-type conductivity in Al-rich AlGaN using multidimensional Mg-doped superlattices

    PubMed Central

    Zheng, T. C.; Lin, W.; Liu, R.; Cai, D. J.; Li, J. C.; Li, S. P.; Kang, J. Y.

    2016-01-01

    A novel multidimensional Mg-doped superlattice (SL) is proposed to enhance vertical hole conductivity in conventional Mg-doped AlGaN SL which generally suffers from large potential barrier for holes. Electronic structure calculations within the first-principle theoretical framework indicate that the densities of states (DOS) of the valence band nearby the Fermi level are more delocalized along the c-axis than that in conventional SL, and the potential barrier significantly decreases. Hole concentration is greatly enhanced in the barrier of multidimensional SL. Detailed comparisons of partial charges and decomposed DOS reveal that the improvement of vertical conductance may be ascribed to the stronger pz hybridization between Mg and N. Based on the theoretical analysis, highly conductive p-type multidimensional Al0.63Ga0.37N/Al0.51Ga0.49N SLs are grown with identified steps via metalorganic vapor-phase epitaxy. The hole concentration reaches up to 3.5 × 1018 cm−3, while the corresponding resistivity reduces to 0.7 Ω cm at room temperature, which is tens times improvement in conductivity compared with that of conventional SLs. High hole concentration can be maintained even at 100 K. High p-type conductivity in Al-rich structural material is an important step for the future design of superior AlGaN-based deep ultraviolet devices. PMID:26906334

  18. Shear deformation-induced anisotropic thermal conductivity of graphene.

    PubMed

    Cui, Liu; Shi, Sanqiang; Wei, Gaosheng; Du, Xiaoze

    2018-01-03

    Graphene-based materials exhibit intriguing phononic and thermal properties. In this paper, we have investigated the heat conductance in graphene sheets under shear-strain-induced wrinkling deformation, using equilibrium molecular dynamics simulations. A significant orientation dependence of the thermal conductivity of graphene wrinkles (GWs) is observed. The directional dependence of the thermal conductivity of GWs stems from the anisotropy of phonon group velocities as revealed by the G-band broadening of the phonon density of states (DOS), the anisotropy of thermal resistance as evidenced by the G-band peak mismatch of the phonon DOS, and the anisotropy of phonon relaxation times as a direct result of the double-exponential-fitting of the heat current autocorrelation function. By analyzing the relative contributions of different lattice vibrations to the heat flux, we have shown that the contributions of different lattice vibrations to the heat flux of GWs are sensitive to the heat flux direction, which further indicates the orientation-dependent thermal conductivity of GWs. Moreover, we have found that, in the strain range of 0-0.1, the anisotropy ratio of GWs increases monotonously with increasing shear strain. This is induced by the change in the number of wrinkles, which is more influential in the direction perpendicular to the wrinkle texture. The findings elucidated here emphasize the utility of wrinkle engineering for manipulation of nanoscale heat transport, which offers opportunities for the development of thermal channeling devices.

  19. Density of states-based design of metal oxide thin-film transistors for high mobility and superior photostability.

    PubMed

    Kim, Hyun-Suk; Park, Joon Seok; Jeong, Hyun-Kwang; Son, Kyoung Seok; Kim, Tae Sang; Seon, Jong-Baek; Lee, Eunha; Chung, Jae Gwan; Kim, Dae Hwan; Ryu, Myungkwan; Lee, Sang Yoon

    2012-10-24

    A novel method to design metal oxide thin-film transistor (TFT) devices with high performance and high photostability for next-generation flat-panel displays is reported. Here, we developed bilayer metal oxide TFTs, where the front channel consists of indium-zinc-oxide (IZO) and the back channel material on top of it is hafnium-indium-zinc-oxide (HIZO). Density-of-states (DOS)-based modeling and device simulation were performed in order to determine the optimum thickness ratio within the IZO/HIZO stack that results in the best balance between device performance and stability. As a result, respective values of 5 and 40 nm for the IZO and HIZO layers were determined. The TFT devices that were fabricated accordingly exhibited mobility values up to 48 cm(2)/(V s), which is much elevated compared to pure HIZO TFTs (∼13 cm(2)/(V s)) but comparable to pure IZO TFTs (∼59 cm(2)/(V s)). Also, the stability of the bilayer device (-1.18 V) was significantly enhanced compared to the pure IZO device (-9.08 V). Our methodology based on the subgap DOS model and simulation provides an effective way to enhance the device stability while retaining a relatively high mobility, which makes the corresponding devices suitable for ultradefinition, large-area, and high-frame-rate display applications.

  20. Atomic theory of viscoelastic response and memory effects in metallic glasses

    NASA Astrophysics Data System (ADS)

    Cui, Bingyu; Yang, Jie; Qiao, Jichao; Jiang, Minqiang; Dai, Lanhong; Wang, Yun-Jiang; Zaccone, Alessio

    2017-09-01

    An atomic-scale theory of the viscoelastic response of metallic glasses is derived from first principles, using a Zwanzig-Caldeira-Leggett system-bath Hamiltonian as a starting point within the framework of nonaffine linear response to mechanical deformation. This approach provides a generalized Langevin equation (GLE) as the average equation of motion for an atom or ion in the material, from which non-Markovian nonaffine viscoelastic moduli are extracted. These can be evaluated using the vibrational density of states (DOS) as input, where the boson peak plays a prominent role in the mechanics. To compare with experimental data for binary ZrCu alloys, a numerical DOS was obtained from simulations of this system, which also take electronic degrees of freedom into account via the embedded-atom method for the interatomic potential. It is shown that the viscoelastic α -relaxation, including the α -wing asymmetry in the loss modulus, can be very well described by the theory if the memory kernel (the non-Markovian friction) in the GLE is taken to be a stretched-exponential decaying function of time. This finding directly implies strong memory effects in the atomic-scale dynamics and suggests that the α -relaxation time is related to the characteristic time scale over which atoms retain memory of their previous collision history. This memory time grows dramatically below the glass transition.

  1. The interaction of mercury with halogenated graphene

    NASA Astrophysics Data System (ADS)

    Kirchofer, Abigail; Sasmaz, Erdem; Wilcox, Jennifer

    2011-03-01

    The interaction of mercury with halogenated graphene was studied using plane-wave density functional theory. Various configurations of H, Hg, O and Br or Cl on the zigzag edge sites of graphene were investigated. Although Hg-Br (or -Cl) complexes were found to be stable on the surface, the most stable configurations found were those with Hg adjacent to O. The surface atoms Hg, O, and Br tend to repel each other during geometric optimization, moving towards an H atom nearest-neighbor where possible. The strength of the Hg-graphene interaction is very sensitive to the local environment. The Hg-graphene binding energy is strongest when the Hg is located next to a surface O but not immediately next to a bound Br. DOS analysis revealed that Hg adsorption involves a gain in Hg 6 p-states and a loss in Hg 5 s electron density, resulting in an oxidized surface-bound Hg complex. DOS analysis suggests that Br strengthens the Hg-graphene interaction by modifying the surface carbon electron density; however, when Br is adjacent to Hg, a direct Hg-Br interaction weakens the Hg-C bond. These investigations provide insight into the mechanism associated with enhanced Hg adsorption on Br-functionalized carbon materials for Hg emissions reductions from coal-fired power plant applications. The authors acknowledge the financial support by Electric Power Research Institute (EPRI).

  2. Theoretical investigations of electrical transport properties in CoSb3 skutterudites under hydrostatic loadings

    DOE PAGES

    Hu, Chongze; Ni, Peter; Zhan, Li; ...

    2018-01-30

    We report that CoSb 3-based skutterudites have been a benchmark mid-temperature thermoelectric material under intensive experimental and theoretical studies for decades. Doping and filling, to the first order, alter the crystal lattice constant of CoSb 3 in the context of “chemical pressure.” In this work, we employed ab initio density functional theory in conjunction with semiclassical Boltzmann transport theory to investigate the mechanical properties and especially how hydrostatic loadings, i.e., “physical pressure,” impact the electronic band structure, Seebeck coefficient, and power factor of pristine CoSb 3. It is found that hydrostatic pressure enlarges the band gap, suppresses the density ofmore » states (DOS) near the valence band edge, and fosters the band convergence between the valley bands and the conduction band minimum (CBM). By contrast, hydrostatic tensile reduces the band gap, increases the DOS near the valence band edge, and diminishes the valley bands near the CBM. Therefore, applying hydrostatic pressure provides an alternative avenue for achieving band convergence to improve thermoelectric properties of N-type CoSb 3, which is further supported by our carrier concentration studies. Lastly, these results provide valuable insight into the further improvement of thermoelectric performance of CoSb 3-based skutterudites via a synergy of physical and chemical pressures.« less

  3. 27 CFR 9.175 - Dos Rios.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... of this chapter, “Dos Rios” is a term of viticultural significance. (b) Approved Maps. The..., T22N, R14W, west of Eberle Ridge, (Iron Peak Quadrangle); and (15) Proceed generally southeast along...

  4. 27 CFR 9.175 - Dos Rios.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... of this chapter, “Dos Rios” is a term of viticultural significance. (b) Approved Maps. The..., T22N, R14W, west of Eberle Ridge, (Iron Peak Quadrangle); and (15) Proceed generally southeast along...

  5. Influence of addition of degassed water on bulk nanobubbles.

    PubMed

    Tuziuti, Toru; Yasui, Kyuichi; Kanematsu, Wataru

    2018-05-01

    The effects of the addition of degassed water on bulk nanobubbles (ultrafine bubbles) of air in liquid water were investigated by measuring the volumetric concentration and size distribution at different dissolved air degree of saturation (DOS) values. The proportion of degassed water mixed with water containing bulk nanobubbles was increased to prepare samples having lower DOS values. It was found that the volumetric concentration of nanobubbles mostly decreased and the average nanobubble size became larger as the DOS was decreased. In our proposed mechanism, smaller nanobubbles are selectively dissolved into the surrounding liquid by Laplace pressure due to surface tension as the DOS is reduced. These results demonstrate that stable bulk nanobubbles are present even in water undersaturated with gas. The role of nanobubble under an ultrasound is also discussed. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Magnetic disorder in superconductors: Enhancement by mesoscopic fluctuations

    NASA Astrophysics Data System (ADS)

    Burmistrov, I. S.; Skvortsov, M. A.

    2018-01-01

    We study the density of states (DOS) and the transition temperature Tc in a dirty superconducting film with rare classical magnetic impurities of an arbitrary strength described by the Poissonian statistics. We take into account that the potential disorder is a source of mesoscopic fluctuations of the local DOS, and, consequently, of the effective strength of magnetic impurities. We find that these mesoscopic fluctuations result in a nonzero DOS for all energies in the region of the phase diagram where without this effect the DOS is zero within the standard mean-field theory. This mechanism can be more efficient in filling the mean-field superconducting gap than rare fluctuations of the potential disorder (instantons). Depending on the magnetic impurity strength, the suppression of Tc by spin-flip scattering can be faster or slower than in the standard mean-field theory.

  7. Feasibility of outpatient total hip and knee arthroplasty in unselected patients

    PubMed Central

    Gromov, Kirill; Kjærsgaard-Andersen, Per; Revald, Peter; Kehlet, Henrik; Husted, Henrik

    2017-01-01

    Background and purpose The number of patients who are suitable for outpatient total hip and knee arthroplasty (THA and TKA) in an unselected patient population remains unknown. The purpose of this prospective 2-center study was to identify the number of patients suitable for outpatient THA and TKA in an unselected patient population, to investigate the proportion of patients who were discharged on the day of surgery (DOS), and to identify reasons for not being discharged on the DOS. Patients and methods All consecutive, unselected patients who were referred to 2 participating centers and who were scheduled for primary THA and TKA were screened for eligibility for outpatient surgery with discharge to home on DOS. If patients did not fulfill the discharge criteria, the reasons preventing discharge were noted. Odds factors with relative risk intervals for not being discharged on DOS were identified while adjusting for age, sex, ASA score, BMI and distance to home. Results Of the 557 patients who were referred to the participating surgeons during the study period, 54% were potentially eligible for outpatient surgery. Actual DOS discharge occurred in 13–15% of the 557 patients. Female sex and surgery late in the day increased the odds of not being discharged on the DOS. Interpretation This study shows that even in unselected THA and TKA patients, same-day discharge is feasible in about 15% of patients. Future studies should evaluate safety aspects and economic benefits. PMID:28426262

  8. Experimental and theoretical studies of vibrational density of states in Fe3O4 single-crystalline thin films

    NASA Astrophysics Data System (ADS)

    Handke, B.; Kozłowski, A.; Parliński, K.; Przewoźnik, J.; Ślęzak, T.; Chumakov, A. I.; Niesen, L.; Kąkol, Z.; Korecki, J.

    2005-04-01

    This paper presents experimental and theoretical studies of lattice vibrations in a single-crystalline Fe3O4(001) thin film. The investigations were carried out in order to see how the lattice dynamics changes at the Verwey transition. Vibrational densities of states (DOS) were obtained from nuclear inelastic scattering (NIS) of synchrotron radiation in the temperature range 25 to 296 K, while theoretical DOS were calculated ab initio within density functional theory. Experimental phonon density of states shows good agreement with calculated DOS, reproducing both the general features of main line groups as well as the groups’ structure. This is also in qualitative accord with heat capacity data, provided that experimental DOS is augmented with that calculated for oxygen atoms. We have observed a gradual change in the NIS raw data as well as the relevant DOS while lowering the temperature. In particular, the main peak in the energy region 15-25 meV shows increasing splitting on cooling. The Lamb-Mössbauer factor calculated in the course of DOS evaluation shows a pronounced drop in the vicinity of the Verwey transition that may be partly connected to the observed abrupt lowering of the count rate at approximately 7 meV for T

  9. Social Networking Family of Caregivers during Hospitalization of Children.

    PubMed

    Menezes, Marina; Moré, Carmen Leontina Ojeda Ocampo; Barros, Luísa

    2016-06-01

    To identify and analyze the significant networks of family, social and hospital support described by the family caregivers of hospitalized children 5-12 years during the hospital stay. Descriptive study, exploratory and qualitative study conducted with 20 caregivers of children hospitalized in a hospital in a city in southern Brazil, through semi-structured interviews and significant social networks maps, tailored to the hospital setting. Data analysis showed that the most active social network was comprised of families through emotional support, material aid and services. Relations with hospital health care team and the hospital context were cited as providing support to the caregivers of the hospitalized child. The identification of social networks in the child's hospitalization course enables equip professionals working in the institution aiming at better targeting of actions and care for the family and hospitalized children. Identificar e analisar as redes significativas de suporte familiar, social e hospitalar descritas pelos familiares acompanhantes de crianças hospitalizadas de 5 a 12 anos, durante o período de internação. Estudo descritivo, exploratório e de cunho qualitativo realizado com 20 acompanhantes de crianças hospitalizadas em uma unidade hospitalar em uma cidade do Sul do Brasil, por meio de entrevistas semiestruturadas e dos Mapas de Redes sociais significativas, adaptado para o contexto hospitalar. A análise dos dados demonstrou que a rede social mais atuante foi composta por familiares, através de apoio emocional, ajuda material e de serviços. As relações com a equipe de saúde do hospital e com o contexto hospitalar foram citadas como capazes de fornecer apoio ao acompanhante da criança internada. a identificação das redes sociais no curso da hospitalização da criança possibilita instrumentalizar os profissionais que atuam na instituição objetivando um melhor direcionamento de ações e cuidados destinados à família e a criança hospitalizada.

  10. CRISP90 - SOFTWARE DESIGN ANALYZER SYSTEM

    NASA Technical Reports Server (NTRS)

    Tausworthe, R. C.

    1994-01-01

    The CRISP90 Software Design Analyzer System, an update of CRISP-80, is a set of programs forming a software design and documentation tool which supports top-down, hierarchic, modular, structured design and programming methodologies. The quality of a computer program can often be significantly influenced by the design medium in which the program is developed. The medium must foster the expression of the programmer's ideas easily and quickly, and it must permit flexible and facile alterations, additions, and deletions to these ideas as the design evolves. The CRISP90 software design analyzer system was developed to provide the PDL (Programmer Design Language) programmer with such a design medium. A program design using CRISP90 consists of short, English-like textual descriptions of data, interfaces, and procedures that are imbedded in a simple, structured, modular syntax. The display is formatted into two-dimensional, flowchart-like segments for a graphic presentation of the design. Together with a good interactive full-screen editor or word processor, the CRISP90 design analyzer becomes a powerful tool for the programmer. In addition to being a text formatter, the CRISP90 system prepares material that would be tedious and error prone to extract manually, such as a table of contents, module directory, structure (tier) chart, cross-references, and a statistics report on the characteristics of the design. Referenced modules are marked by schematic logic symbols to show conditional, iterative, and/or concurrent invocation in the program. A keyword usage profile can be generated automatically and glossary definitions inserted into the output documentation. Another feature is the capability to detect changes that were made between versions. Thus, "change-bars" can be placed in the output document along with a list of changed pages and a version history report. Also, items may be marked as "to be determined" and each will appear on a special table until the item is supplied. The CRISP90 software design analyzer system is written in Microsoft QuickBasic. The program requires an IBM PC compatible with a hard disk, 128K RAM, and an ASCII printer. The program operates under MS-DOS/PC-DOS 3.10 or later. The program was developed in 1983 and updated in 1990. Microsoft and MS-DOS are registered trademarks of Microsoft Corporation. IBM PC and PC-DOS are registered trademarks of International Business Machines Corporation. CRISP90 is a copyrighted work with all copyright vested in NASA.

  11. Tunnelling spectroscopy of gate-induced superconductivity in MoS2

    NASA Astrophysics Data System (ADS)

    Costanzo, Davide; Zhang, Haijing; Reddy, Bojja Aditya; Berger, Helmuth; Morpurgo, Alberto F.

    2018-06-01

    The ability to gate-induce superconductivity by electrostatic charge accumulation is a recent breakthrough in physics and nanoelectronics. With the exception of LaAlO3/SrTiO3 interfaces, experiments on gate-induced superconductors have been largely confined to resistance measurements, which provide very limited information about the superconducting state. Here, we explore gate-induced superconductivity in MoS2 by performing tunnelling spectroscopy to determine the energy-dependent density of states (DOS) for different levels of electron density n. In the superconducting state, the DOS is strongly suppressed at energy smaller than the gap Δ, which is maximum (Δ 2 meV) for n of 1 × 1014 cm-2 and decreases monotonously for larger n. A perpendicular magnetic field B generates states at E < Δ that fill the gap, but a 20% DOS suppression of superconducting origin unexpectedly persists much above the transport critical field. Conversely, an in-plane field up to 10 T leaves the DOS entirely unchanged. Our measurements exclude that the superconducting state in MoS2 is fully gapped and reveal the presence of a DOS that vanishes linearly with energy, the explanation of which requires going beyond a conventional, purely phonon-driven Bardeen-Cooper-Schrieffer mechanism.

  12. The trap DOS in small molecule organic semiconductors: A quantitative comparison of thin-film transistors with single crystals

    NASA Astrophysics Data System (ADS)

    Kalb, Wolfgang; Haas, Simon; Pernstich, Kurt; Mathis, Thomas; Batlogg, Bertram

    2010-03-01

    Our study shows that it is possible to reach one of the ultimate goals of organic electronics: organic field-effect transistors can be produced with trap densities as low as in the bulk of single crystals. Several analytical methods to calculate the spectral density of localized states in the band gap (trap DOS) from measured data were used to clarify, if the different methods lead to similar results. We then compared quantitatively trap DOS information from the literature, correcting for differences due to different calculation methods. In the bulk of single crystals the trap DOS is lower by several orders of magnitude than in thin films. The compilation of all data strongly suggests that structural defects at grain boundaries are the main cause of ``fast'' traps in TFT's made with vacuum-evaporated pentacene. For high-performance transistors made with small molecule semiconductors such as rubrene it is essential to reduce the dipolar disorder caused by water adsorbed on the gate dielectric. We will discuss to what degree band broadening due to the thermal fluctuations of the intermolecular transfer integral is reflected in the trap DOS very close (<0.15 eV) to the mobility edge.

  13. Chemical Modification and Structure-property Relationships of Acrylic and Ionomeric Thermoplastic Elastomer Gels

    NASA Astrophysics Data System (ADS)

    Vargantwar, Pruthesh Hariharrao

    Block copolymers (BCs) have remained at the forefront of materials research due to their versatility in applications ranging from hot-melt/pressure-sensitive adhesives and impact modifiers to compatibilizing agents and vibration-dampening/nanotemplating media. Of particular interest are macromolecules composed of two or more chemically dissimilar blocks covalently linked together to form triblock or pentablock copolymers. If the blocks are sufficiently incompatible and the copolymer behaves as a thermoplastic elastomer, the molecules can spontaneously self-assemble to form nanostructured materials that exhibit shape memory due to the formation of a supramolecular network. The BCs of these types are termed as conventional. When BCs contain blocks having ionic moieties such as sulfonic acid groups, they are termed as block ionomers. Designing new systems based on either conventional or ionic BCs, characterizing their structure-property relationships and later using them as electroacive polymers form the essential objectives of this work. Electroactive polymers (EAPs) exhibit electromechanical actuation when stimulated by an external electric field. In the first part of this work, it is shown that BCs resolve some of the outstanding problems presently encountered in the design of two different classes of EAP actuators: dielectric elastomers (DEs) and ionic polymer metal composites (IPMCs). All-acrylic triblock copolymer gels used as DEs actuate with high efficacy without any requirement of mechanical prestrain and, thus, eliminate the need for bulky and heavy hardware essential with prestrained dielectric actuators, as well as material problems associated with stress relaxation. The dependence of actuation behavior on gel morphology as evaluated from mechanical and microstructure studies is observed. In the case of IPMCs, ionic BCs employed in this study greatly facilitate processing compared to other contenders such as NafionRTM, which is commonly used in this class of EAPs. The unique copolymer investigated here (i) retains its mechanical integrity when highly solvated by polar solvents, (ii) demonstrates a high degree of actuation when tested in a cantilever configuration, and (iii) avoids the shortcomings of back-relaxation/overshoot within the testing conditions when used in combination with an appropriate solvent. In the second part of this work, two chemical strategies to design midblock sulfonated block ionomers are explored. In one case, selective sulfonation of the midblocks in triblock copolymers is achieved via a dioxane:sulfur trioxide chemistry, while in the other acetyl sulfate is used for the same purpose. Excellent control on the degree of sulfonation (DOS) is achieved. The block ionomers swell in different solvents while retaining their mechanical integrity. They show disorder-order, order-order, and order-reduced order morphological transitions as DOS varies. These transitions in morphologies are reflected in their thermal behavior as well. The microstructures show periodicity, which is, again, a function of DOS. The transitions are explained in terms of the molar volume expansion and volume densification of the blocks on sulfonation. The ionic levels, morphology and periodicity in microstructure are important for applications such as actuators, sensors and fuel cell membranes. The ability to tune these aspects in the ionomers designed in this work make them potential candidates for these applications.

  14. Acoustic Purcell Effect for Enhanced Emission

    NASA Astrophysics Data System (ADS)

    Landi, Maryam; Zhao, Jiajun; Prather, Wayne E.; Wu, Ying; Zhang, Likun

    2018-03-01

    We observe that our experimentally measured emission power enhancement of a speaker inside a previously proposed metacavity agrees with our numerically calculated enhancement of the density of states (DOS) of the source-cavity system. We interpret the agreement by formulating a relation between the emitted sound power and the acoustic DOS. The formulation is an analog to Fermi's golden rule in quantum emission. The formulation complements the radiation impedance theory in traditional acoustics for describing sound emission. Our study bridges the gap between acoustic DOS and the acoustic Purcell effect for sound emission enhancement.

  15. Fuzzy model to estimate the number of hospitalizations for asthma and pneumonia under the effects of air pollution.

    PubMed

    Chaves, Luciano Eustáquio; Nascimento, Luiz Fernando Costa; Rizol, Paloma Maria Silva Rocha

    2017-06-22

    Predict the number of hospitalizations for asthma and pneumonia associated with exposure to air pollutants in the city of São José dos Campos, São Paulo State. This is a computational model using fuzzy logic based on Mamdani's inference method. For the fuzzification of the input variables of particulate matter, ozone, sulfur dioxide and apparent temperature, we considered two relevancy functions for each variable with the linguistic approach: good and bad. For the output variable number of hospitalizations for asthma and pneumonia, we considered five relevancy functions: very low, low, medium, high and very high. DATASUS was our source for the number of hospitalizations in the year 2007 and the result provided by the model was correlated with the actual data of hospitalization with lag from zero to two days. The accuracy of the model was estimated by the ROC curve for each pollutant and in those lags. In the year of 2007, 1,710 hospitalizations by pneumonia and asthma were recorded in São José dos Campos, State of São Paulo, with a daily average of 4.9 hospitalizations (SD = 2.9). The model output data showed positive and significant correlation (r = 0.38) with the actual data; the accuracies evaluated for the model were higher for sulfur dioxide in lag 0 and 2 and for particulate matter in lag 1. Fuzzy modeling proved accurate for the pollutant exposure effects and hospitalization for pneumonia and asthma approach. Prever o número de internações por asma e pneumonia associadas à exposição a poluentes do ar no município em São José dos Campos, estado de São Paulo. Trata-se de um modelo computacional que utiliza a lógica fuzzy baseado na técnica de inferência de Mamdani. Para a fuzzificação das variáveis de entrada material particulado, ozônio, dióxido de enxofre e temperatura aparente foram consideradas duas funções de pertinência para cada variável com abordagem linguísticas: bom e ruim. Para a variável de saída número internações por asma e pneumonia, foram consideradas cinco funções de pertinências: muito baixo, baixo, médio, alto e muito alto. O número de internações no ano de 2007 foi obtido do Datasus e o resultado fornecido pelo modelo foi correlacionado com os dados reais de internação com defasagem (lag) de zero a dois dias. A acurácia do modelo foi estimada pela curva ROC para cada poluente e nestas defasagens. No ano de 2007 foram registradas 1.710 internações por pneumonia e asma em São José dos Campos, SP, com média diária de 4,9 internações (dp = 2,9). Os dados de saída do modelo mostraram correlação positiva e significativa (r = 0,38) com os dados reais; as acurácias avaliadas para o modelo foram maiores para o dióxido de enxofre nos lag 0 e 2 e para o material particulado no lag 1. Modelagem fuzzy se mostrou acurada para a abordagem de efeitos da exposição aos poluentes e internação por pneumonia e asma.

  16. The Relationship Between Preoperative and Primary Care Blood Pressure Among Veterans Presenting from Home for Surgery. Is There Evidence for Anesthesiologist-Initiated Blood Pressure Referral?

    PubMed Central

    Schonberger, Robert B.; Burg, Matthew M.; Holt, Natalie; Lukens, Carrie L.; Dai, Feng; Brandt, Cynthia

    2011-01-01

    Background American College of Cardiology/American Heart Association guidelines describe the perioperative evaluation as “a unique opportunity to identify patients with hypertension,” however factors such as anticipatory stress or medication noncompliance may induce a bias toward higher blood pressure, leaving clinicians unsure about how to interpret preoperative hypertension. Information describing the relationship between preoperative intake blood pressure and primary care measurements could help anesthesiologists make primary care referrals for improved blood pressure control in an evidence-based fashion. We hypothesized that the preoperative examination provides a useful basis for initiating primary care blood pressure referral. Methods We analyzed retrospective data on 2807 patients who arrived from home for surgery and who were subsequently evaluated within 6 months after surgery in the primary care center of the same institution. After descriptive analysis, we conducted multiple linear regression analysis to identify day-of-surgery (DOS) factors associated with subsequent primary care blood pressure. We calculated the sensitivity, specificity, and positive and negative predictive value of different blood pressure referral thresholds using both a single-measurement and a two-stage screen incorporating recent preoperative and DOS measurements for identifying patients with subsequently elevated primary care blood pressure. Results DOS systolic blood pressure (SBP) was higher than subsequent primary care SBP by a mean bias of 5.5mmHg (95% limits of agreement +43.8 to −32.8). DOS diastolic blood pressure (DBP) was higher than subsequent primary care DBP by a mean bias of 1.5mmHg (95% limits of agreement +13.0 to −10.0). Linear regression of DOS factors explained 19% of the variability in primary care SBP and 29% of the variability in DBP. Accounting for the observed bias, a two-stage SBP referral screen requiring preoperative clinic SBP≥140mmHg and DOS SBP≥146mmHg had 95.9% estimated specificity (95% CI 94.4 to 97.0) for identifying subsequent primary care SBP≥140mmHg and estimated sensitivity of 26.8% (95% CI 22.0 to 32.0). A similarly high specificity using a single DOS SBP required a threshold SBP≥160mmHg, for which estimated specificity was 95.2% (95% CI 94.2 to 96.1). For DBP, a presenting DOS DBP≥92mmHg had 95.7% specificity (95% CI 94.8 to 96.4) for subsequent primary care DBP≥90mmHg with a sensitivity of 18.8% (95% CI 14.4 to 24.0). Conclusion A small bias toward higher DOS blood pressures relative to subsequent primary care measurements was observed. DOS factors predicted only a small proportion of the observed variation. Accounting for the observed bias, a two-stage SBP threshold and a single-reading DBP threshold were highly specific though insensitive for identifying subsequent primary care blood pressure elevation. PMID:22075017

  17. Effect of O2 plasma treatment on density-of-states in a-IGZO thin film transistors

    NASA Astrophysics Data System (ADS)

    Ding, Xingwei; Huang, Fei; Li, Sheng; Zhang, Jianhua; Jiang, Xueyin; Zhang, Zhilin

    2017-01-01

    This work reports an efficient route for enhancing the performance of amorphous InGaZnO (a-IGZO) thin film transistors (TFT). The mobility was greatly improved by about 38% by means of O2 plasma treatment. Temperature-stress was carried out to investigate the stability and extract the parameters related to activation energy ( E a) and density-of-states (DOS). The DOS was calculated on the basis of the experimentally obtained E a, which can explain the experimental observation. A lower activation energy ( E a, 0.72 eV) and a smaller DOS were obtained in the O2 plasma treatment TFT based on the temperature-dependent transfer curves. The results showed that temperature stability and electrical properties enhancements in a-IGZO thin film transistors were attributed to the smaller DOS. [Figure not available: see fulltext.

  18. Two regimes in the magnetic field response of superconducting MgB2

    NASA Astrophysics Data System (ADS)

    Kohen, A.; Giubileo, F.; Proslier, Th.; Bobba, F.; Cucolo, A. M.; Sacks, W.; Noat, Y.; Troianovski, A.; Roditchev, D.

    2007-05-01

    Using Scanning Tunneling Microscope at low temperature we explore the superconducting phase diagram in the π-band of the two-band superconductor MgB2. In this band the peculiar shape of the local tunneling spectra and their dynamics in the magnetic field reveal the complex character of the quasiparticle density of states (DOS). The gap in the DOS is first rapidly filled with states in raising the magnetic field up to 0.5 T and then slowly approaches the normal state value: the gap is observed up to 2 T. Such a change in the DOS dynamics suggests the existence of two terms in the DOS of the π-band: a first one, reflecting an intrinsic superconductivity in the band and a second one, originating from an inter-band coupling to the σ-band. Our findings allow a deeper understanding of the unique phase diagram of MgB2.

  19. Charge Transport Properties in Disordered Organic Semiconductor as a Function of Charge Density: Monte Carlo Simulation

    NASA Astrophysics Data System (ADS)

    Shukri, Seyfan Kelil

    2017-01-01

    We have done Kinetic Monte Carlo (KMC) simulations to investigate the effect of charge carrier density on the electrical conductivity and carrier mobility in disordered organic semiconductors using a lattice model. The density of state (DOS) of the system are considered to be Gaussian and exponential. Our simulations reveal that the mobility of the charge carrier increases with charge carrier density for both DOSs. In contrast, the mobility of charge carriers decreases as the disorder increases. In addition the shape of the DOS has a significance effect on the charge transport properties as a function of density which are clearly seen. On the other hand, for the same distribution width and at low carrier density, the change occurred on the conductivity and mobility for a Gaussian DOS is more pronounced than that for the exponential DOS.

  20. Diversity-oriented synthetic strategy for developing a chemical modulator of protein-protein interaction

    NASA Astrophysics Data System (ADS)

    Kim, Jonghoon; Jung, Jinjoo; Koo, Jaeyoung; Cho, Wansang; Lee, Won Seok; Kim, Chanwoo; Park, Wonwoo; Park, Seung Bum

    2016-10-01

    Diversity-oriented synthesis (DOS) can provide a collection of diverse and complex drug-like small molecules, which is critical in the development of new chemical probes for biological research of undruggable targets. However, the design and synthesis of small-molecule libraries with improved biological relevance as well as maximized molecular diversity represent a key challenge. Herein, we employ functional group-pairing strategy for the DOS of a chemical library containing privileged substructures, pyrimidodiazepine or pyrimidine moieties, as chemical navigators towards unexplored bioactive chemical space. To validate the utility of this DOS library, we identify a new small-molecule inhibitor of leucyl-tRNA synthetase-RagD protein-protein interaction, which regulates the amino acid-dependent activation of mechanistic target of rapamycin complex 1 signalling pathway. This work highlights that privileged substructure-based DOS strategy can be a powerful research tool for the construction of drug-like compounds to address challenging biological targets.

  1. Dissecting the protein architecture of DNA-binding transcription factors in bacteria and archaea.

    PubMed

    Rivera-Gómez, Nancy; Martínez-Núñez, Mario Alberto; Pastor, Nina; Rodriguez-Vazquez, Katya; Perez-Rueda, Ernesto

    2017-08-01

    Gene regulation at the transcriptional level is a central process in all organisms where DNA-binding transcription factors play a fundamental role. This class of proteins binds specifically at DNA sequences, activating or repressing gene expression as a function of the cell's metabolic status, operator context and ligand-binding status, among other factors, through the DNA-binding domain (DBD). In addition, TFs may contain partner domains (PaDos), which are involved in ligand binding and protein-protein interactions. In this work, we systematically evaluated the distribution, abundance and domain organization of DNA-binding TFs in 799 non-redundant bacterial and archaeal genomes. We found that the distributions of the DBDs and their corresponding PaDos correlated with the size of the genome. We also identified specific combinations between the DBDs and their corresponding PaDos. Within each class of DBDs there are differences in the actual angle formed at the dimerization interface, responding to the presence/absence of ligands and/or crystallization conditions, setting the orientation of the resulting helices and wings facing the DNA. Our results highlight the importance of PaDos as central elements that enhance the diversity of regulatory functions in all bacterial and archaeal organisms, and our results also demonstrate the role of PaDos in sensing diverse signal compounds. The highly specific interactions between DBDs and PaDos observed in this work, together with our structural analysis highlighting the difficulty in predicting both inter-domain geometry and quaternary structure, suggest that these systems appeared once and evolved with diverse duplication events in all the analysed organisms.

  2. Evidence for abiotic sulfurization of marine dissolved organic matter in sulfidic environments

    NASA Astrophysics Data System (ADS)

    Pohlabeln, A. M.; Niggemann, J.; Dittmar, T.

    2016-02-01

    Sedimentary organic matter abiotically sulfurizes in sulfidic marine environments. Here we hypothesize that sulfurization also affects dissolved organic matter (DOM), and that sulfidic marine environments are sources of dissolved organic sulfur (DOS) to the ocean. To test these hypotheses we studied solid-phase extractable (SPE) DOS in the Black Sea at various water column depths (oxic and anoxic) and in sediment porewaters from the German Wadden Sea. The concentration and molecular composition of SPE-DOS from these sites and from the oxic water columns of the North Sea (Germany) and of the North Pacific were compared. In support of our hypotheses, SPE-DOS concentrations were elevated in sulfidic waters compared to oxic waters. For a detailed molecular characterization of SPE-DOS, selective wet-chemical alteration experiments targeting different sulfur-containing functional groups were applied prior to Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). These experiments included harsh hydrolysis, selective derivatization of thiols, oxidation, and deoxygenation to test for thioesters, sulfonic acid esters, alkylsulfates, thiols, non-aromatic thioethers, and sulfoxides. Additionally, collision-induced fragmentation experiments were applied to test for sulfonic acids. The tests revealed that the sulfonic acid group was the main structural feature in SPE-DOS, independent of the environmental conditions of the sampling site. Only in Wadden Sea anoxic porewater also non-aromatic thioethers were found which are presumably not stable in oxic waters. The findings from our field studies were confirmed in laboratory experiments, where we abiotically sulfurized marine and algal-derived DOM under conditions similar to that in anoxic marine sediments.

  3. Toward noninvasive detection and monitoring of malaria with broadband diffuse optical spectroscopy

    NASA Astrophysics Data System (ADS)

    Campbell, Chris; Tromberg, Bruce J.; O'Sullivan, Thomas D.

    2018-02-01

    Despite numerous advances, malaria continues to kill nearly half a million people globally every year. New analytical methods and diagnostics are critical to understanding how treatments under development affect the lifecycle of malaria parasites. A biomarker that has been gaining interest is the "malaria pigment" hemozoin. This byproduct of hemoglobin digestion by the parasite has a unique spectral signature but is difficult to differentiate from hemoglobin and other tissue chromophores. Hemozoin can be detected in blood samples, but only utilizing approaches that require specialized training and facilities. Diffuse optical spectroscopy (DOS) is a noninvasive sensing technique that is sensitive to near-infrared absorption and scattering and capable of probing centimeter-deep volumes of tissue in vivo. DOS is relatively low-cost, does not require specialized training and thus potentially suitable for use in low-resource settings. In this work, we assess the potential of DOS to detect and quantify the presence of hemozoin noninvasively and at physiologically relevant levels. We suspended synthetic hemozoin in Intralipid-based tissue-simulating phantoms in order to mimic malaria infection in multiply-scattering tissue. Using a fiber probe that combines frequency-domain and continuous-wave broadband DOS (650-1000 nm), we detected hemozoin concentrations below 250 ng/ml, which corresponds to parasitemia sensitivities comparable to modern rapid diagnostic tests. We used the experimental variability to simulate and estimate the sensitivity of DOS to hemozoin in tissue that includes hemoglobin, water, and lipid under various tissue oxygen saturation levels. The results indicate that with increased precision, it may be possible to detect Hz noninvasively with DOS.

  4. A DOS Primer for Librarians: Part II.

    ERIC Educational Resources Information Center

    Beecher, Henry

    1990-01-01

    Provides an introduction to DOS commands and strategies for the effective organization and use of hard disks. Functions discussed include the creation of directories and subdirectories, enhanced copying, the assignment of disk drives, and backing up the hard disk. (CLB)

  5. 78 FR 67018 - Airworthiness Directives; Embraer S.A. Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-08

    ... dos Campos, Sao Paulo, Brasil; phone: (+55 12) 3927-1000; Fax: (+55 12) 3927-6600, Ext. 1448; email..., CEP: 12227-901, Sao Jose dos Campos, Sao Paulo, Brasil; phone: (+55 12) 3927-1000; Fax: (+55 12) 3927...

  6. EVALUATION OF POSTGRADUATES STRICTO SENSU: MONITORING POLICY FOR INTERNATIONAL GRADUATES.

    PubMed

    Lima, Wilma Terezinha Anselmo

    2015-01-01

    Search for references in relationship to international alumni on the website of the postgraduate programs of all postgraduate courses at Ribeirão Preto Medical School - FMRP. Verify with more attention to the ones with 5, 6 and 7 notes, and also the same search on the website of courses with notes 5, 6 and 7 of CAPES - Medicine III. Of the 22 programs of FMRP only three had any information on the site about the destiny of the postgraduates; they were: Surgical Clinics, Genetics, and Basic and Applied Immunology. Programs in the area of ​​Medicine III, notes 5, 6 and 7, only Ophthalmology and Visual Programs and Translational Sciences Surgery, both of UNIFESP, presented such information. It is urgent: to create project and funding evaluation mechanisms that are approved by different sources; to stimulate more efficient controls in relation to teachers and their students who participate in these projects; and to stimulate the interaction of teachers and students with the institution and the program. Verificar a existência de referências aos egressos internacionais nos sites dos programas de pós-graduação de todos os cursos de pós-graduação da Faculdade de Medicina de Ribeirão Preto - FMRP. Verificar com mais atenção aos cursos notas 5, 6 e 7, e também a mesma busca nos sites dos cursos com notas 5, 6 e 7 da Medicina III da CAPES. Dos 22 programas da FMRP apenas três tinham no site alguma informação sobre o destino dos egressos, foram eles: Clínica Cirúrgica, Genética e Imunologia Básica e Aplicada. Dos programas da área de Medicina III, notas 5, 6 e 7 apenas os programas de Oftalmologia e Ciências Visuais e Cirurgia Translacional, ambos da UNIFESP, apresentavam informações sobre o destino dos seus egressos. É urgente criar mecanismos de avaliação para os projetos de incentivo e fomento à pesquisa dos diferentes órgãos; estimular controles mais eficientes e atualizados em relação aos docentes e seus respectivos discentes que participam desses projetos; e estimular a interação dos docentes e discentes com a instituição e o programa.

  7. Calcium Isotopic Anomalies in the Allende CAIs and the Angrite Angra dos Reis

    NASA Astrophysics Data System (ADS)

    Chen, H. W.; Chen, J. C.; Lee, T.; Shen, J. J.

    2010-03-01

    Both negative 48Ca and 50Ti anomalies of the Angrite Angra dos Reis was identified in this study, and the result supported previous study of correlated negative 54Cr and 50Ti anomalies in achondrites.

  8. HEC-RAS 2.2 for backwater and scour analysis - phase one

    DOT National Transportation Integrated Search

    2000-09-01

    The Kansas Department of Transportation (KDOT) and most bridge consultants in Kansas have been using the DOS-WSPRO program and the KDOT scour spreadsheets to perform bridge hydraulics and scour analysis for the past several years. Unfortunately, DOS-...

  9. 33 CFR 105.245 - Declaration of Security (DoS).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) of this section. (e) At MARSEC Levels 1 and 2, FSOs of facilities that frequently interface with the... part to implement a DoS with the VSO prior to any vessel-to-facility interface when he or she deems it...

  10. 33 CFR 105.245 - Declaration of Security (DoS).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) of this section. (e) At MARSEC Levels 1 and 2, FSOs of facilities that frequently interface with the... part to implement a DoS with the VSO prior to any vessel-to-facility interface when he or she deems it...

  11. Disk Operating System User's Guide

    DOT National Transportation Integrated Search

    1972-05-01

    This document serves the purpose of bringing together in one place most of the information a user needs to use the DDP-516 Disk Operating System, (DOS). DOS is a core resident, one user, console-oriented operating system which allows the user to cont...

  12. 77 FR 72776 - Airworthiness Directives; Embraer S.A. Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-06

    .... Brigadeiro Faria Lima, 2170--Putim--12227-901 S[atilde]o Jose dos Campos-SP- BRASIL; telephone +55 12 3927...--Putim--12227-901 S[atilde]o Jose dos Campos--SP--BRASIL; telephone +55 12 3927-5852 or +55 12 3309-0732...

  13. 78 FR 12256 - Airworthiness Directives; Embraer S.A. Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-22

    .... Brigadeiro Faria Lima, 2170--Putim--12227-901 S[atilde]o Jose dos Campos--SP-- BRASIL; telephone +55 12 3927... Lima, 2170--Putim--12227-901 S[atilde]o Jose dos Campos--SP--BRASIL; telephone +55 12 3927-5852 or +55...

  14. 77 FR 63272 - Airworthiness Directives; Embraer S.A. Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-16

    ... Faria Lima, 2170--Putim-12227-901 S[atilde]o Jose dos Campos-SP-- BRASIL; telephone +55 12 3927-5852 or... Section (PC 060), Av. Brigadeiro Faria Lima, 2170-Putim-12227-901 S[atilde]o Jose dos Campos-SP-BRASIL...

  15. Incorporating structural analysis in a quantum dot Monte-Carlo model

    NASA Astrophysics Data System (ADS)

    Butler, I. M. E.; Li, Wei; Sobhani, S. A.; Babazadeh, N.; Ross, I. M.; Nishi, K.; Takemasa, K.; Sugawara, M.; Peyvast, Negin; Childs, D. T. D.; Hogg, R. A.

    2018-02-01

    We simulate the shape of the density of states (DoS) of the quantum dot (QD) ensemble based upon size information provided by high angle annular dark field scanning transmission electron microscopy (HAADF STEM). We discuss how the capability to determined the QD DoS from micro-structural data allows a MonteCarlo model to be developed to accurately describe the QD gain and spontaneous emission spectra. The QD DoS shape is then studied, with recommendations made via the effect of removing, and enhancing this size inhomogeneity on various QD based devices is explored.

  16. Intraoperative optical assessment of photodynamic therapy response of superficial oral squamous cell carcinoma

    NASA Astrophysics Data System (ADS)

    Rohrbach, Daniel J.; Rigual, Nestor; Arshad, Hassan; Tracy, Erin C.; Cooper, Michelle T.; Shafirstein, Gal; Wilding, Gregory; Merzianu, Mihai; Baumann, Heinz; Henderson, Barbara W.; Sunar, Ulas

    2016-01-01

    This study investigated whether diffuse optical spectroscopy (DOS) measurements could assess clinical response to photodynamic therapy (PDT) in patients with head and neck squamous cell carcinoma (HNSCC). In addition, the correlation between parameters measured with DOS and the crosslinking of signal transducer and activator of transcription 3 (STAT3), a molecular marker for PDT-induced photoreaction, was investigated. Thirteen patients with early stage HNSCC received the photosensitizer 2-[1-hexyloxyethyl]-2-devinylpyropheophorbide-a (HPPH) and DOS measurements were performed before and after PDT in the operating room (OR). In addition, biopsies were acquired after PDT to assess the STAT3 crosslinking. Parameters measured with DOS, including blood volume fraction, blood oxygen saturation (StO2), HPPH concentration (cHPPH), HPPH fluorescence, and blood flow index (BFI), were compared to the pathologic response and the STAT3 crosslinking. The best individual predictor of pathological response was a change in cHPPH (sensitivity=60%, specificity=100%), while discrimination analysis using a two-parameter classifier (change in cHPPH and change in StO2) classified pathological response with 100% sensitivity and 100% specificity. BFI showed the best correlation with the crosslinking of STAT3. These results indicate that DOS-derived parameters can assess the clinical response in the OR, allowing for earlier reintervention if needed.

  17. Development and Characterization of a Camelid Single Domain Antibody–Urease Conjugate That Targets Vascular Endothelial Growth Factor Receptor 2

    PubMed Central

    Tian, Baomin; Wong, Wah Yau; Uger, Marni D.; Wisniewski, Pawel; Chao, Heman

    2017-01-01

    Angiogenesis is the process of new blood vessel formation and is essential for a tumor to grow beyond a certain size. Tumors secrete the pro-angiogenic factor vascular endothelial growth factor, which acts upon local endothelial cells by binding to vascular endothelial growth factor receptors (VEGFRs). In this study, we describe the development and characterization of V21-DOS47, an immunoconjugate that targets VEGFR2. V21-DOS47 is composed of a camelid single domain anti-VEGFR2 antibody (V21) and the enzyme urease. The conjugate specifically binds to VEGFR2 and urease converts endogenous urea into ammonia, which is toxic to tumor cells. Previously, we developed a similar antibody–urease conjugate, L-DOS47, which is currently in clinical trials for non-small cell lung cancer. Although V21-DOS47 was designed from parameters learned from the generation of L-DOS47, additional optimization was required to produce V21-DOS47. In this study, we describe the expression and purification of two versions of the V21 antibody: V21H1 and V21H4. Each was conjugated to urease using a different chemical cross-linker. The conjugates were characterized by a panel of analytical techniques, including SDS-PAGE, size exclusion chromatography, Western blotting, and LC-MSE peptide mapping. Binding characteristics were determined by ELISA and flow cytometry assays. To improve the stability of the conjugates at physiologic pH, the pIs of the V21 antibodies were adjusted by adding several amino acid residues to the C-terminus. For V21H4, a terminal cysteine was also added for use in the conjugation chemistry. The modified V21 antibodies were expressed in the E. coli BL21 (DE3) pT7 system. V21H1 was conjugated to urease using the heterobifunctional cross-linker succinimidyl-[(N-maleimidopropionamido)-diethyleneglycol] ester (SM(PEG)2), which targets lysine resides in the antibody. V21H4 was conjugated to urease using the homobifunctional cross-linker, 1,8-bis(maleimido)diethylene glycol (BM(PEG)2), which targets the cysteine added to the antibody C-terminus. V21H4-DOS47 was determined to be the superior conjugate as the antibody is easily produced and purified at high levels, and the conjugate can be efficiently generated and purified using methods easily transferrable for cGMP production. In addition, V21H4-DOS47 retains higher binding activity than V21H1-DOS47, as the native lysine residues are unmodified. PMID:28871252

  18. Early detection of chemotherapy-refractory patients by monitoring textural alterations in diffuse optical spectroscopic images

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sadeghi-Naini, Ali; Falou, Omar; Czarnota, Gregory J., E-mail: Gregory.Czarnota@sunnybrook.ca

    2015-11-15

    Purpose: Changes in textural characteristics of diffuse optical spectroscopic (DOS) functional images, accompanied by alterations in their mean values, are demonstrated here for the first time as early surrogates of ultimate treatment response in locally advanced breast cancer (LABC) patients receiving neoadjuvant chemotherapy (NAC). NAC, as a standard component of treatment for LABC patient, induces measurable heterogeneous changes in tumor metabolism which were evaluated using DOS-based metabolic maps. This study characterizes such inhomogeneous nature of response development, by determining alterations in textural properties of DOS images apparent at early stages of therapy, followed later by gross changes in mean valuesmore » of these functional metabolic maps. Methods: Twelve LABC patients undergoing NAC were scanned before and at four times after treatment initiation, and tomographic DOS images were reconstructed at each time. Ultimate responses of patients were determined clinically and pathologically, based on a reduction in tumor size and assessment of residual tumor cellularity. The mean-value parameters and textural features were extracted from volumetric DOS images for several functional and metabolic parameters prior to the treatment initiation. Changes in these DOS-based biomarkers were also monitored over the course of treatment. The measured biomarkers were applied to differentiate patient responses noninvasively and compared to clinical and pathologic responses. Results: Responding and nonresponding patients demonstrated different changes in DOS-based textural and mean-value parameters during chemotherapy. Whereas none of the biomarkers measured prior the start of therapy demonstrated a significant difference between the two patient populations, statistically significant differences were observed at week one after treatment initiation using the relative change in contrast/homogeneity of seven functional maps (0.001 < p < 0.049), and mean value of water content in tissue (p = 0.010). The cross-validated sensitivity and specificity of these parameters at week one of therapy ranged between 80%–100% and 67%–100%, respectively. Higher levels of statistically significant differences were exhibited at week four after start of treatment, with cross-validated sensitivities and specificities ranging between 80% and 100% for three textural and three mean-value parameters. The combination of the textural and mean-value parameters in a “hybrid” profile could better separate the two patient populations early on during a course of treatment, with cross-validated sensitivities and specificities of up to 100% (p = 0.001). Conclusions: The results of this study suggest that alterations in textural characteristics of DOS images, in conjunction with changes in their mean values, can classify noninvasively the ultimate clinical and pathologic response of LABC patients to chemotherapy, as early as one week after start of their treatment. This provides a basis for using DOS imaging as a tool for therapy personalization.« less

  19. In vivo prediction of goat kids body composition from the deuterium oxide dilution space determined by isotope-ratio mass spectrometry.

    PubMed

    Lerch, S; Lastel, M L; Grandclaudon, C; Brechet, C; Rychen, G; Feidt, C

    2015-09-01

    Deuterium oxide dilution space (DOS) determination is one of the most accurate methods for in vivo estimation of ruminant body composition. However, the time-consuming vacuum sublimation of blood preceding infrared spectroscopy analysis, which is traditionally used to determine deuterium oxide (DO) concentration, limits its current use. The use of isotope-ratio mass spectrometry (IRMS) to determine the deuterium enrichment and thus quantify DO in plasma could counteract this limitation by reducing the sample preparation for plasma deproteinisation through centrifugal filters. The aim of this study was to validate the DOS technique using IRMS in growing goat kids to establish in vivo prediction equations of body composition. Seventeen weaned male Alpine goat kids (8.6 wk old) received a hay-based diet supplemented with 2 types of concentrates providing medium ( = 9) or high ( = 8) energy levels. Kids were slaughtered at 14.0 ( = 1, medium-energy diet), 17.2 ( = 4, medium-energy diet, and = 4, high-energy diet), or 21.2 wk of age ( = 4, medium-energy diet, and = 4, high-energy diet). Two days before slaughter, DOS was determined after an intravenous injection of 0.2 g DO/kg body mass (BM) and the resulting study of DO dilution kinetics from 4 plasma samples (+5, +7, +29, and +31 h after injection). The deuterium enrichment was analyzed by IRMS. After slaughter, the gut contents were discarded, the empty body (EB) was minced, and EB water, lipid, protein, ash, and energy contents were measured by chemical analyses. Prediction equations for body components measured postmortem were computed from in vivo BM and DOS. The lack of postmortem variation of fat-free EB composition was confirmed (mean of 75.3% [SD 0.6] of water), and the proportion of lipids in the EB tended ( = 0.06) to be greater for the high-energy diet (13.1%) than for the medium-energy diet (11.1%). There was a close negative relationship (residual CV [rCV] = 3.9%, = 0.957) between EB water and lipid content, whereas DOS was closely related to total body water (rCV = 2.9%, = 0.944) but DOS overestimated it by 5.8%. Adding DOS to BM improved the in vivo predictions of EB lipid and energy content (rCV = 13.1% and rCV = 7.9%, respectively) but not those of protein or ash. Accuracy of the obtained prediction equations was similar to those reported in studies determining DOS by infrared spectroscopy. Therefore, the use of IRMS to quantify DOS provides a highly accurate measure of the in vivo body composition in goat kids.

  20. Early detection of chemotherapy-refractory patients by monitoring textural alterations in diffuse optical spectroscopic images.

    PubMed

    Sadeghi-Naini, Ali; Vorauer, Eric; Chin, Lee; Falou, Omar; Tran, William T; Wright, Frances C; Gandhi, Sonal; Yaffe, Martin J; Czarnota, Gregory J

    2015-11-01

    Changes in textural characteristics of diffuse optical spectroscopic (DOS) functional images, accompanied by alterations in their mean values, are demonstrated here for the first time as early surrogates of ultimate treatment response in locally advanced breast cancer (LABC) patients receiving neoadjuvant chemotherapy (NAC). NAC, as a standard component of treatment for LABC patient, induces measurable heterogeneous changes in tumor metabolism which were evaluated using DOS-based metabolic maps. This study characterizes such inhomogeneous nature of response development, by determining alterations in textural properties of DOS images apparent at early stages of therapy, followed later by gross changes in mean values of these functional metabolic maps. Twelve LABC patients undergoing NAC were scanned before and at four times after treatment initiation, and tomographic DOS images were reconstructed at each time. Ultimate responses of patients were determined clinically and pathologically, based on a reduction in tumor size and assessment of residual tumor cellularity. The mean-value parameters and textural features were extracted from volumetric DOS images for several functional and metabolic parameters prior to the treatment initiation. Changes in these DOS-based biomarkers were also monitored over the course of treatment. The measured biomarkers were applied to differentiate patient responses noninvasively and compared to clinical and pathologic responses. Responding and nonresponding patients demonstrated different changes in DOS-based textural and mean-value parameters during chemotherapy. Whereas none of the biomarkers measured prior the start of therapy demonstrated a significant difference between the two patient populations, statistically significant differences were observed at week one after treatment initiation using the relative change in contrast/homogeneity of seven functional maps (0.001

  1. Study of hydrogen in phthalocyanine semiconductors using muSR technique =

    NASA Astrophysics Data System (ADS)

    Duarte, Joao Pedro Piroto Pereira

    Este trabalho apresenta um estudo experimental dos semicondutores organicos Ftalocianina (H2Pc), Ftalocianina de Zinco (ZnPc) e Ftalocianina de Cobre (CuPc) por tecnicas de µSR, tendo-se obtido informacao detalhada sobre a estrutura electronica dos estados de carga formados pelo muao positivo nos tres compostos, e sobre as interaccoes dinamicas a que esses estados se encontram sujeitos. Os resultados do estudo indicam que nas ftalocianias com caracter nao magneticas H2Pc e ZnPc se da a formacao de tres radicais muonicos paramagneticos distintos. A estrutura hiperfina destes radicais, referidos como estados I, II e III, foi caracterizada atraves da medida dos parametros de acoplamento hipefino em conjunto com a parameterizacao da sua dependencia com a temperatura. Uma quarta componente paramagnetica do sinal µSR foi tambem identificada, mas sobre a qual nao foi possivel retirar conclusoes definitivas quanto a sua origem. Verificou-se que os parametros de acoplamento hiperfino isotropicos dos tres estados identificados se encontram numa regiao de valores entre os 100 e os 150MHz para os estados I e II, enquanto que para o estado III esta quantidade toma valores em torno de 10 MHz. A estrutura electronica de todos os estados possui simetria axial, caracterizada por parametros dipolares de cerca de 15MHz para os estados I e II, e 20MHz para o estado III. A origem dos estados I e II foi determinada como sendo devida a adicao de muonio a uma das ligacoes duplas existentes nos aneis benzenicos da periferia das moleculas de ftalocianina recorrendo a calculos de estrutura electronica, tendo-se verificado a existencia de um acoplamento entre a interaccao hiperfina desses estados e modos vibracionais desses aneis. A problematica da localizacao do estado III tambem foi abordada, tomando-se como hipotese mais provavel uma posicao intersticial entre duas moleculas de ftalocianina. O estudo das interaccoes dinamicas de spin destes tres estados revelou que o estado III esta sujeito a um fenomeno de spin exchange, originado pela colisao com portadores de carga presentes no material. A taxa de spin-flip relativa a esta interaccao foi deduzida a partir de medidas µSR em geometria de campo longitudinal, tendo sida determinada a barreira energetica existente para a difusao de portadores de carga entre moleculas de ftalocianina localizadas dentro da mesma estrutura colunar tanto na H2Pc, como na ZnPc. Por fim, o sinal µSR da ftalocianina com caracter magnetico CuPc foi tambem caracterizado. Foram identificadas duas componentes de caracter aparentemente diamagnetico com taxas de relaxacao separadas por cerca de duas ordens de grandeza, atribuidas a duas configuracoes distintas para o emparelhamento entre o electrao do radical muonico, e o electrao com spin desemparelhado localizado no atomo de cobre. Os dois emparelhamentos diferentes geram um ambiente puramente diamagnetico para o muao, o que origina a componente de relaxacao lenta, e uma configuracao na qual existe uma densidade de spin flutuante na posicao do muao, responsavel pela componente de relaxacao elevada.

  2. 78 FR 33201 - Airworthiness Directives; Embraer S.A. Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-04

    .... Brigadeiro Faria Lima, 2170-Putim-12227-901 S[atilde]o Jose dos Campos-SP-BRASIL; telephone +55 12 3927-5852...[atilde]o Jose dos Campos-SP-BRASIL; telephone +55 12 3927-5852 or +55 12 3309-0732; fax +55 12 3927-7546...

  3. A Concepção de Universo entre Alunos do Ensino Médio de São Paulo e suas Fontes de Aquisição

    NASA Astrophysics Data System (ADS)

    Araújo, M. A. A.; Elias, D. C. N.; Amaral, L. H.; Araújo, M. S. T.; Voelzke, M. R.

    2006-08-01

    Nesse trabalho procurou-se identificar por meio de um questionário as concepções de Universo, de espaço e tempo que sustentam a visão de mundo de um grupo de 270 estudantes de Ensino Médio, pertencentes a três escolas de São Paulo. As questões relacionadas aos conhecimentos prévios dos estudantes permitiram constatar que há pouco conhecimento acerca dos temas investigados, destacando-se que apenas 20% dos alunos foram capazes de relacionar as semanas com as fases da lua, enquanto 28% associaram as estações do ano à inclinação do eixo de rotação da Terra e 23% tinham noções das distâncias entre objetos celestes próximos da Terra. Enquanto 56% conseguiram relacionar o Big Bang com a origem do Universo, verificou-se que 37% reconheciam ano-luz como unidade de distância e 60% concebiam o Sol como uma estrela. No que se refere às fontes de aquisição que proporcionaram esses conhecimentos, apesar de 60% dos alunos indicarem a escola como principal fonte dos conhecimentos de Ast! ronomia, verificou-se claramente que para a maioria dos alunos seus conceitos ainda são inadequados, havendo necessidade de aprimoramento da abordagem desses conteúdos, pois apesar de popular, a Astronomia ainda é veiculada de maneira pouco esclarecedora e com imprecisões. Nesse contexto, são discutidas algumas possíveis contribuições que podem ser dadas para o ensino de Astronomia pelo uso das ferramentas computacionais nas escolas.

  4. 77 FR 36224 - Airworthiness Directives; Empresa Brasileira de Aeronautica S.A. (EMBRAER) Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-18

    ... dos Campos--SP--BRASIL; telephone +55 12 3927-5852 or +55 12 3309-0732; fax +55 12 3927-7546; email.... Brigadeiro Faria Lima, 2170-- Putim--12227-901 S[atilde]o Jose dos Campos--SP--BRASIL; telephone +55 12 3927...

  5. 78 FR 66258 - Airworthiness Directives; Empresa Brasileira de Aeronautica S.A. (EMBRAER) Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-05

    ..., 2170--Putim--12227-901 S[atilde]o Jose dos Campos--SP--BRASIL; telephone +55 12 3927-5852 or +55 12... Faria Lima, 2170-- Putim--12227-901 S[atilde]o Jose dos Campos--SP--BRASIL; telephone +55 12 3927-5852...

  6. Deep Learning Method for Denial of Service Attack Detection Based on Restricted Boltzmann Machine.

    PubMed

    Imamverdiyev, Yadigar; Abdullayeva, Fargana

    2018-06-01

    In this article, the application of the deep learning method based on Gaussian-Bernoulli type restricted Boltzmann machine (RBM) to the detection of denial of service (DoS) attacks is considered. To increase the DoS attack detection accuracy, seven additional layers are added between the visible and the hidden layers of the RBM. Accurate results in DoS attack detection are obtained by optimization of the hyperparameters of the proposed deep RBM model. The form of the RBM that allows application of the continuous data is used. In this type of RBM, the probability distribution of the visible layer is replaced by a Gaussian distribution. Comparative analysis of the accuracy of the proposed method with Bernoulli-Bernoulli RBM, Gaussian-Bernoulli RBM, deep belief network type deep learning methods on DoS attack detection is provided. Detection accuracy of the methods is verified on the NSL-KDD data set. Higher accuracy from the proposed multilayer deep Gaussian-Bernoulli type RBM is obtained.

  7. tRNA-mediated codon-biased translation in mycobacterial hypoxic persistence

    NASA Astrophysics Data System (ADS)

    Chionh, Yok Hian; McBee, Megan; Babu, I. Ramesh; Hia, Fabian; Lin, Wenwei; Zhao, Wei; Cao, Jianshu; Dziergowska, Agnieszka; Malkiewicz, Andrzej; Begley, Thomas J.; Alonso, Sylvie; Dedon, Peter C.

    2016-11-01

    Microbial pathogens adapt to the stress of infection by regulating transcription, translation and protein modification. We report that changes in gene expression in hypoxia-induced non-replicating persistence in mycobacteria--which models tuberculous granulomas--are partly determined by a mechanism of tRNA reprogramming and codon-biased translation. Mycobacterium bovis BCG responded to each stage of hypoxia and aerobic resuscitation by uniquely reprogramming 40 modified ribonucleosides in tRNA, which correlate with selective translation of mRNAs from families of codon-biased persistence genes. For example, early hypoxia increases wobble cmo5U in tRNAThr(UGU), which parallels translation of transcripts enriched in its cognate codon, ACG, including the DosR master regulator of hypoxic bacteriostasis. Codon re-engineering of dosR exaggerates hypoxia-induced changes in codon-biased DosR translation, with altered dosR expression revealing unanticipated effects on bacterial survival during hypoxia. These results reveal a coordinated system of tRNA modifications and translation of codon-biased transcripts that enhance expression of stress response proteins in mycobacteria.

  8. tRNA-mediated codon-biased translation in mycobacterial hypoxic persistence

    PubMed Central

    Chionh, Yok Hian; McBee, Megan; Babu, I. Ramesh; Hia, Fabian; Lin, Wenwei; Zhao, Wei; Cao, Jianshu; Dziergowska, Agnieszka; Malkiewicz, Andrzej; Begley, Thomas J.; Alonso, Sylvie; Dedon, Peter C.

    2016-01-01

    Microbial pathogens adapt to the stress of infection by regulating transcription, translation and protein modification. We report that changes in gene expression in hypoxia-induced non-replicating persistence in mycobacteria—which models tuberculous granulomas—are partly determined by a mechanism of tRNA reprogramming and codon-biased translation. Mycobacterium bovis BCG responded to each stage of hypoxia and aerobic resuscitation by uniquely reprogramming 40 modified ribonucleosides in tRNA, which correlate with selective translation of mRNAs from families of codon-biased persistence genes. For example, early hypoxia increases wobble cmo5U in tRNAThr(UGU), which parallels translation of transcripts enriched in its cognate codon, ACG, including the DosR master regulator of hypoxic bacteriostasis. Codon re-engineering of dosR exaggerates hypoxia-induced changes in codon-biased DosR translation, with altered dosR expression revealing unanticipated effects on bacterial survival during hypoxia. These results reveal a coordinated system of tRNA modifications and translation of codon-biased transcripts that enhance expression of stress response proteins in mycobacteria. PMID:27834374

  9. Effective Patient-Physician Communication Based on Osteopathic Philosophy in Caring for Elderly Patients.

    PubMed

    Noll, Donald R; Ginsberg, Terrie; Elahi, Abdul; Cavalieri, Thomas A

    2016-01-01

    The objective of this article is to discuss effective communication strategies between elderly patients and their physicians from the perspective of osteopathic heritage. The patient-physician communication styles of Andrew Taylor Still, MD, DO, and early osteopathic physicians (ie, DOs) may have influenced how DOs today communicate with their patients. Historical literature describes how Still would discuss with his patients the causes of their health problems using analogies and language they would understand, and how, when caring for a patient at the end of life, he empathically provided emotional support for both patients and their families. Early DOs advocated setting clear expectations for patients regarding clinical outcomes and carefully listening to patients to build trust. The Osteopathic Oath, which calls for the DO to view the patient as a friend, may also affect patient-physician communication. Early osteopathic philosophy and culture, as modeled by Dr Still in his approach to elderly patients, should inspire today's DOs in their communication with their elderly patients.

  10. Density of photon states in dye-doped chiral nematic liquid crystal cells in the presence of losses and gain.

    PubMed

    Mavrogordatos, Th K; Morris, S M; Castles, F; Hands, P J W; Ford, A D; Coles, H J; Wilkinson, T D

    2012-07-01

    We calculate the density of photon states (DOS) of the normal modes in dye-doped chiral nematic liquid crystal (LC) cells in the presence of various loss mechanisms. Losses and gain are incorporated into the transmission characteristics through the introduction of a small imaginary part in the dielectric constant perpendicular and along the director, for which we assume no frequency dispersion. Theoretical results are presented on the DOS in the region of the photonic band gap for a range of values of the loss coefficient and different values of the optical anisotropy. The obtained values of the DOS at the photonic band gap edges predict a reversal of the dominant modes in the structure. Our results are found to be in good agreement with the experimentally obtained excitation thresholds in chiral nematic LC lasers. The behavior of the DOS is also discussed for amplifying LC cells providing additional insight to the lasing mechanism of these structures.

  11. Components for the Global Digital Object Cloud

    NASA Astrophysics Data System (ADS)

    Glaves, Helen; Hanahoe, Hilary; Weigel, Tobias; Lannom, Larry; Wittenburg, Peter; Koureas, Dimitris; Almas, Bridget

    2017-04-01

    We are at a tipping point in the development of a common conceptual framework and set of tools and components which will revolutionize the management of scientific data. It is widely acknowledged that the current volumes and complexity of data now being collected, and the inevitable and enormous increase in that volume and complexity, have reached the point where action is required. Around 80% of the data generated is being lost after short time periods and a corresponding amount of time is being wasted by reseachers on routine data management tasks. At the same time, and largely in response to this perceived crisis, a number of principles (G8, RDA DFT, FAIR) for the management of scientific data have arisen and been widely endorsed. The danger now is that agreement will stop at the level of principles and that multiple non-interoperable domain and technology specific silos will continue to arise, all based on the abstract principles. If this happens, we will lose the opportunity to create a common set of low-level tools and components based on an agreed conceptual approach. The Research Data Alliance (RDA) is now combining recommendations from its individual working and interest groups, such as suggestions for proper citation of dynamic data or how to assess the quality of repositories, to design configurations of core components (as specified by RDA and other initiatives such as W3C) and stimulate their implementation. Together with a few global communities such as climate modeling, biodiversity and material science, experts involved in RDA are developing a concept called Global Digital Object Cloud (GDOC) which has the potential to overcome the huge fragmentation which hampers efficient data management and re-use. It is compliant with the FAIR principles in so far as a) it puts Digital Objects (DOs) in its center, b) has all DOs assigned PIDs which are resolvable to useful state information, c) has all DOs associated with metadata, and d) has all DO bit sequences stored in trustworthy repositories. The presentation will give an overview of the types of components involved, the corresponding specifications of RDA, and the concept of the GDOC.

  12. Quantum multicriticality in disordered Weyl semimetals

    NASA Astrophysics Data System (ADS)

    Luo, Xunlong; Xu, Baolong; Ohtsuki, Tomi; Shindou, Ryuichi

    2018-01-01

    In electronic band structure of solid-state material, two band-touching points with linear dispersion appear in pairs in the momentum space. When they annihilate each other, the system undergoes a quantum phase transition from a three-dimensional (3D) Weyl semimetal (WSM) phase to a band insulator phase such as a Chern band insulator (CI) phase. The phase transition is described by a new critical theory with a "magnetic dipole"-like object in the momentum space. In this paper, we reveal that the critical theory hosts a novel disorder-driven quantum multicritical point, which is encompassed by three quantum phases: a renormalized WSM phase, a CI phase, and a diffusive metal (DM) phase. Based on the renormalization group argument, we first clarify scaling properties around the band-touching points at the quantum multicritical point as well as all phase boundaries among these three phases. Based on numerical calculations of localization length, density of states, and critical conductance distribution, we next prove that a localization-delocalization transition between the CI phase with a finite zero-energy density of states (zDOS) and DM phase belongs to an ordinary 3D unitary class. Meanwhile, a localization-delocalization transition between the Chern insulator phase with zero zDOS and a renormalized WSM phase turns out to be a direct phase transition whose critical exponent ν =0.80 ±0.01 . We interpret these numerical results by a renormalization group analysis on the critical theory.

  13. [Quali-quantitative study on healthcare for children below the age of 3 at health establishments in nine underdeveloped regions of Peru].

    PubMed

    Cordero Muñoz, Luis Germán; Montes Jave, Cecilia; Velásquez Hurtado, José Enrique; Rodríguez Calviño, Yuleika; Vigo Valdez, Walter Eduardo; Rosas-Aguirre, Ángel Martín

    2016-03-01

    To assess five elements of healthcare quality (physical space, equipment, personnel, waiting time, and counseling) in growth and development services (GDS) at 18 healthcare establishments in nine regions of Peru with high rates of poverty. A quali-quantitative study was carried out in the Amazonas, Apurímac, Ayacucho, Cajamarca, Cusco, Huánuco, Huancavelica, Puno, and Ucayali regions, that included direct observation (DO) during medical assistance in GDS, focus groups (FG, one user per healthcare establishment), and in-depth interviews (IDI) with healthcare workers (two per healthcare establishment). There were 18 DOs carried out to assess environment and equipment, 23 DOs of complete service shifts, 67 accompaniments to users during medical assistance in GDS, 18 FGs (118 participating mothers), and 36 IDIs. Both mothers and healthcare professionals agreed that there were limitations in infrastructure, equipment, materials, and personnel that impacted quality medical assistance in GDS. Delays in medical assistance, failure to comply with schedules, and lack of friendliness when providing medical care were the aspects that produced the greatest user dissatisfaction. Only 24.3% of the total amount of time spent at the healthcare establishment corresponded to beneficial activities for the user, although the Health Department was meeting the objective to promote improvement of childcare practices. The study was useful in identifying weaknesses and strengths that may help redirect GDS efforts within the framework of policies aimed at strengthening first-class medical assistance.

  14. Regulation, circulation and distribution of penicillin in Portugal (1944-1954).

    PubMed

    Bell, Victoria; Rui Pita, João; Pereira, Ana Leonor

    Portugal did not participate in World War II but was one of the first countries in the world to receive penicillin for civilian use. The Portuguese Red Cross began to import the antibiotic from the United States of America in 1944 and appointed a controlling committee to oversee its distribution, due to the small amount available. In 1945, as world production increased, penicillin began to be distributed through the normal channels. An important role in its regulation was played by the official department responsible for controlling pharmaceutical and chemical products in Portugal, the Comissão Reguladora dos Produtos Químicos e Farmacêuticos (Regulatory Committee for Chemical and Pharmaceutical Products). Penicillin was imported as a raw material from 1947 and the first medicaments containing penicillin, prepared in Portugal, were released into the commercial circuit in 1948. A laboratory had been established in 1942 by the Comissão Reguladora for the analytical verification of medicaments and medicinal products with the aim of certifying their quality and minimizing the number of products with no attested therapeutic efficacy. The number of medicaments analysed by this laboratory increased substantially from 72 in the year of its foundation (1942) to 2478 in 1954, including, after 1948, medicaments containing penicillin. The aim of the present paper was to elucidate the role of the Comissão Reguladora dos Produtos Químicos e Farmacêuticos in regulating and controlling the distribution of penicillin in Portugal during the 1940s and 1950s.

  15. Micromechanical combined stress analysis: MICSTRAN, a user manual

    NASA Technical Reports Server (NTRS)

    Naik, R. A.

    1992-01-01

    Composite materials are currently being used in aerospace and other applications. The ability to tailor the composite properties by the appropriate selection of its constituents, the fiber and matrix, is a major advantage of composite materials. The Micromechanical Combined Stress Analysis (MICSTRAN) code provides the materials engineer with a user-friendly personal computer (PC) based tool to calculate overall composite properties given the constituent fiber and matrix properties. To assess the ability of the composite to carry structural loads, the materials engineer also needs to calculate the internal stresses in the composite material. MICSTRAN is a simple tool to calculate such internal stresses with a composite ply under combined thermomechanical loading. It assumes that the fibers have a circular cross-section and are arranged either in a repeating square or diamond array pattern within a ply. It uses a classical elasticity solution technique that has been demonstrated to calculate accurate stress results. Input to the program consists of transversely isotropic fiber properties and isotropic matrix properties such as moduli, Poisson's ratios, coefficients of thermal expansion, and volume fraction. Output consists of overall thermoelastic constants and stresses. Stresses can be computed under the combined action of thermal, transverse, longitudinal, transverse shear, and longitudinal shear loadings. Stress output can be requested along the fiber-matrix interface, the model boundaries, circular arcs, or at user-specified points located anywhere in the model. The MICSTRAN program is Windows compatible and takes advantage of the Microsoft Windows graphical user interface which facilitates multitasking and extends memory access far beyond the limits imposed by the DOS operating system.

  16. Finite-size Scaling of the Density of States in Photonic Band Gap Crystals

    NASA Astrophysics Data System (ADS)

    Hasan, Shakeeb Bin; Mosk, Allard P.; Vos, Willem L.; Lagendijk, Ad

    2018-06-01

    The famous vanishing of the density of states (DOS) in a band gap, be it photonic or electronic, pertains to the infinite-crystal limit. In contrast, all experiments and device applications refer to finite crystals, which raises the question: Upon increasing the linear size L of a crystal, how fast does the DOS approach the infinite-crystal limit? We present a theory for finite crystals that includes Bloch-mode broadening due to the presence of crystal boundaries. Our results demonstrate that the DOS for frequencies inside a band gap has a 1 /L scale dependence for crystals in one, two and three dimensions.

  17. Coulomb gap triptych in a periodic array of metal nanocrystals.

    PubMed

    Chen, Tianran; Skinner, Brian; Shklovskii, B I

    2012-09-21

    The Coulomb gap in the single-particle density of states (DOS) is a universal consequence of electron-electron interaction in disordered systems with localized electron states. Here we show that in arrays of monodisperse metallic nanocrystals, there is not one but three identical adjacent Coulomb gaps, which together form a structure that we call a "Coulomb gap triptych." We calculate the DOS and the conductivity in two- and three-dimensional arrays using a computer simulation. Unlike in the conventional Coulomb glass models, in nanocrystal arrays the DOS has a fixed width in the limit of large disorder. The Coulomb gap triptych can be studied via tunneling experiments.

  18. 48 CFR 609.406-3 - Procedures.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... statement from each DOS organizational element affected by the debarment action as to the impact of a... is responsible for making the transcribed record of the hearing, unless the contractor and the fact... decision to each DOS organizational element affected by the decision and to the General Services...

  19. Choosing the Right Database Management Program.

    ERIC Educational Resources Information Center

    Vockell, Edward L.; Kopenec, Donald

    1989-01-01

    Provides a comparison of four database management programs commonly used in schools: AppleWorks, the DOS 3.3 and ProDOS versions of PFS, and MECC's Data Handler. Topics discussed include information storage, spelling checkers, editing functions, search strategies, graphs, printout formats, library applications, and HyperCard. (LRW)

  20. Is There a Disk of Satellites around the Milky Way?

    NASA Astrophysics Data System (ADS)

    Maji, Moupiya; Zhu, Qirong; Marinacci, Federico; Li, Yuexing

    2017-07-01

    The “disk of satellites” (DoS) around the Milky Way is a highly debated topic with conflicting interpretations of observations and their theoretical models. We perform a comprehensive analysis of all of the dwarfs detected in the Milky Way and find that the DoS structure depends strongly on the plane identification method and the sample size. In particular, we demonstrate that a small sample size can artificially produce a highly anisotropic spatial distribution and a strong clustering of the angular momentum of the satellites. Moreover, we calculate the evolution of the 11 classical satellites with proper motion measurements and find that the thin DoS in which they currently reside is transient. Furthermore, we analyze two cosmological simulations using the same initial conditions of a Milky-Way-sized galaxy, an N-body run with dark matter only, and a hydrodynamic one with both baryonic and dark matter, and find that the hydrodynamic simulation produces a more anisotropic distribution of satellites than the N-body one. Our results suggest that an anisotropic distribution of satellites in galaxies can originate from baryonic processes in the hierarchical structure formation model, but the claimed highly flattened, coherently rotating DoS of the Milky Way may be biased by the small-number selection effect. These findings may help resolve the contradictory claims of DoS in galaxies and the discrepancy among numerical simulations.

  1. Is There a Disk of Satellites around the Milky Way?

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Maji, Moupiya; Zhu, Qirong; Li, Yuexing

    2017-07-01

    The “disk of satellites” (DoS) around the Milky Way is a highly debated topic with conflicting interpretations of observations and their theoretical models. We perform a comprehensive analysis of all of the dwarfs detected in the Milky Way and find that the DoS structure depends strongly on the plane identification method and the sample size. In particular, we demonstrate that a small sample size can artificially produce a highly anisotropic spatial distribution and a strong clustering of the angular momentum of the satellites. Moreover, we calculate the evolution of the 11 classical satellites with proper motion measurements and find thatmore » the thin DoS in which they currently reside is transient. Furthermore, we analyze two cosmological simulations using the same initial conditions of a Milky-Way-sized galaxy, an N -body run with dark matter only, and a hydrodynamic one with both baryonic and dark matter, and find that the hydrodynamic simulation produces a more anisotropic distribution of satellites than the N -body one. Our results suggest that an anisotropic distribution of satellites in galaxies can originate from baryonic processes in the hierarchical structure formation model, but the claimed highly flattened, coherently rotating DoS of the Milky Way may be biased by the small-number selection effect. These findings may help resolve the contradictory claims of DoS in galaxies and the discrepancy among numerical simulations.« less

  2. Influence of co-culture with denuded oocytes during in vitro maturation on fertilization and developmental competence of cumulus-enclosed porcine oocytes in a defined system.

    PubMed

    Appeltant, Ruth; Somfai, Tamás; Kikuchi, Kazuhiro; Maes, Dominiek; Van Soom, Ann

    2016-04-01

    Co-culture of cumulus-oocyte complexes (COCs) with denuded oocytes (DOs) during in vitro maturation (IVM) was reported to improve the developmental competence of oocytes via oocyte-secreted factors in cattle. The aim of the present study was to investigate if addition of DOs during IVM can improve in vitro fertilization (IVF) and in vitro culture (IVC) results for oocytes in a defined in vitro production system in pigs. The maturation medium was porcine oocyte medium supplemented with gonadotropins, dbcAMP and β-mercaptoethanol. Cumulus-oocyte complexes were matured without DOs or with DOs in different ratios (9 COC, 9 COC+16 DO and 9 COC+36 DO). Consequently; oocytes were subjected to IVF as intact COCs or after denudation to examine if DO addition during IVM would affect cumulus or oocyte properties. After fertilization, penetration and normal fertilization rates of zygotes were not different between all tested groups irrespective of denudation before IVF. When zygotes were cultured for 6 days, no difference could be observed between all treatment groups in cleavage rate, blastocyst rate and cell number per blastocyst. In conclusion, irrespective of the ratio, co-culture with DOs during IVM did not improve fertilization parameters and embryo development of cumulus-enclosed porcine oocytes in a defined system. © 2015 Japanese Society of Animal Science.

  3. Fine structure of striations observed in barium plasma injections in the magnetospheric cleft

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Simons, D.J.; Eastman, T.E.; Pongratz, M.B.

    1976-01-01

    In January and November of 1975, the Los Alamos Scientific Laboratory sponsored four high altitude shaped charge barium plasma injections in the magnetospheric cleft region. These experiments were TORDO UNO (January 6), TORDO DOS (January 11), PERIQUITO UNO (November 25), and PERIQUITO DOS (November 28). All four injections took place near 500 km altitude, and optical data were taken from two aircraft and a ground station. The TORDO DOS and the PERIQUITO experiments showed rapid formation of striations (within one minute after injection), and fast horizontal spreading in contrast with TORDO UNO. In PERIQUITO DOS, the debris cloud spread magneticallymore » east-west with a small net northerly motion. TORDO UNO shows very rapid poleward motion, and the remaining two events resulted in magnetically east-west horizontal spreading, with no noticeable poleward motion. Striations observed in the PERIQUITO DOS experiment separate in opposite directions with relative velocities of up to 3 km/sec. These field-aligned structures appear to form in sheets of approximately constant magnetic latitude. Significant spatial variations occur on a scale of less than 200 meters. Spatial frequency power spectra across these striations have been determined at various times. Observations of the debris cloud and the fast barium streak show strong field-aligned coherency of striation fine structure, indicating a field line mapping of transverse electric fields and gradients.« less

  4. 78 FR 45490 - Department of State Acquisition Regulation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-29

    ... being added due to the need to obtain current data to support the Department of State (DOS) financial statements. From a financial accounting perspective, DOS must have a way of keeping track of its capital... DOSAR 652.245- 71, Accounting for Government Property, requests quarterly reporting of U.S. Department...

  5. Low-Budget, Cost-Effective OCR: Optical Character Recognition for MS-DOS Micros.

    ERIC Educational Resources Information Center

    Perez, Ernest

    1990-01-01

    Discusses optical character recognition (OCR) for use with MS-DOS microcomputers. Cost effectiveness is considered, three types of software approaches to character recognition are explained, hardware and operation requirements are described, possible library applications are discussed, future OCR developments are suggested, and a list of OCR…

  6. Towards Quantifying Programmable Logic Controller Resilience Against Intentional Exploits

    DTIC Science & Technology

    2012-03-22

    may improve the SCADA system’s resilience against DoS and man-in-the-middle ( MITM ) attacks. DoS attacks may be mitigated by using the redundant...paths available on the network links. MITM attacks may be mitigated by the data integrity checks associated with the middleware. Figure 4 illustrates

  7. RESPSYST: An Interactive Microcomputer Program for Education.

    ERIC Educational Resources Information Center

    Boyle, Joseph

    1985-01-01

    RESPSYST is a computer program (written in BASICA and using MS-DOS/PC-DOS microcomputers) incorporating more than 20 of the factors that determine gas transport by the cardio-respiratory system. The five-part program discusses most of these factors, provides several question/answer sections, and relies heavily on graphics to demonstrate…

  8. 77 FR 39159 - Airworthiness Directives; Empresa Brasileria de Aeronáutica S.A. (EMBRAER) Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-02

    ... Lima, 2170, S[atilde]o Jos[eacute] dos Campos--SP, CEP: 12227-901--PO Box 36/2, BRASIL; fax ++55 12.... Brigadeiro Faria Lima, 2170, S[atilde]o Jos[eacute] dos Campos--SP, CEP: 12227-901--P.O. Box 36/2, BRASIL...

  9. 75 FR 68684 - Airworthiness Directives; Empresa Brasileira de Aeronautica S.A. (EMBRAER) Model EMB-500 Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-09

    ..., Sao Jose dos Campos--SP, CEP: 12227-901--P.O. Box: 38/2, BRASIL, telephone: ++55 12 3927-5383; fax... Support, Av. Brig. Farina Lima, 2170, Sao Jose dos Campos--SP, CEP: 12227-901--P.O. Box: 38/2, BRASIL...

  10. TS-SRP/PACK - COMPUTER PROGRAMS TO CHARACTERIZE ALLOYS AND PREDICT CYCLIC LIFE USING THE TOTAL STRAIN VERSION OF STRAINRANGE PARTITIONING

    NASA Technical Reports Server (NTRS)

    Saltsman, J. F.

    1994-01-01

    TS-SRP/PACK is a set of computer programs for characterizing and predicting fatigue and creep-fatigue resistance of metallic materials in the high-temperature, long-life regime for isothermal and nonisothermal fatigue. The programs use the total strain version of the Strainrange Partitioning (TS-SRP). The user should be thoroughly familiar with the TS-SRP method before attempting to use any of these programs. The document for this program includes a theory manual as well as a detailed user's manual with a tutorial to guide the user in the proper use of TS-SRP. An extensive database has also been developed in a parallel effort. This database is an excellent source of high-temperature, creep-fatigue test data and can be used with other life-prediction methods as well. Five programs are included in TS-SRP/PACK along with the alloy database. The TABLE program is used to print the datasets, which are in NAMELIST format, in a reader friendly format. INDATA is used to create new datasets or add to existing ones. The FAIL program is used to characterize the failure behavior of an alloy as given by the constants in the strainrange-life relations used by the total strain version of SRP (TS-SRP) and the inelastic strainrange-based version of SRP. The program FLOW is used to characterize the flow behavior (the constitutive response) of an alloy as given by the constants in the flow equations used by TS-SRP. Finally, LIFE is used to predict the life of a specified cycle, using the constants characterizing failure and flow behavior determined by FAIL and FLOW. LIFE is written in interpretive BASIC to avoid compiling and linking every time the equation constants are changed. Four out of five programs in this package are written in FORTRAN 77 for IBM PC series and compatible computers running MS-DOS and are designed to read data using the NAMELIST format statement. The fifth is written in BASIC version 3.0 for IBM PC series and compatible computers running MS-DOS version 3.10. The executables require at least 239K of memory and DOS 3.1 or higher. To compile the source, a Lahey FORTRAN compiler is required. Source code modifications will be necessary if the compiler to be used does not support NAMELIST input. Probably the easiest revision to make is to use a list-directed READ statement. The standard distribution medium for this program is a set of two 5.25 inch 360K MS-DOS format diskettes. The contents of the diskettes are compressed using the PKWARE archiving tools. The utility to unarchive the files, PKUNZIP.EXE, is included. TS-SRP/PACK was developed in 1992.

  11. User's Manual for HPTAM: a Two-Dimensional Heat Pipe Transient Analysis Model, Including the Startup from a Frozen State

    NASA Technical Reports Server (NTRS)

    Tournier, Jean-Michel; El-Genk, Mohamed S.

    1995-01-01

    This report describes the user's manual for 'HPTAM,' a two-dimensional Heat Pipe Transient Analysis Model. HPTAM is described in detail in the UNM-ISNPS-3-1995 report which accompanies the present manual. The model offers a menu that lists a number of working fluids and wall and wick materials from which the user can choose. HPTAM is capable of simulating the startup of heat pipes from either a fully-thawed or frozen condition of the working fluid in the wick structure. The manual includes instructions for installing and running HPTAM on either a UNIX, MS-DOS or VMS operating system. Samples for input and output files are also provided to help the user with the code.

  12. [The archeology of slavery on Jesuit fazendas: first research notes].

    PubMed

    Symanski, Luís Cláudio P; Gomes, Flávio

    2012-12-01

    These preliminary research notes present theoretical and methodological questions regarding a recently inaugurated investigation in historical archeology that intends to analyze daily life under slavery, demographic regimes, cultural practices, and so on. A survey of archeological sites on former 'senzalas' (slave quarters) and slave-owning fazendas in the Paraíba Valley and northern part of the state of Rio de Janeiro is currently in progress. With the cooperation of historians, archeologists, and anthropologists, records of the material culture of slave populations, which originally comprised indigenes and later Africans, are being located at excavations underway on the fazenda that is part of the Jesuit school in Campos dos Goytacazes, Rio de Janeiro, first run by the clergy and later by members of the laity in the seventeenth, eighteenth, and nineteenth centuries.

  13. PCDAS Version 2. 2: Remote network control and data acquisition

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fishbaugher, M.J.

    1987-09-01

    This manual is intended for both technical and non-technical people who want to use the PCDAS remote network control and data acquisition software. If you are unfamiliar with remote data collection hardware systems designed at Pacific Northwest Laboratory (PNL), this introduction should answer your basic questions. Even if you have some experience with the PNL-designed Field Data Acquisition Systems (FDAS), it would be wise to review this material before attempting to set up a network. This manual was written based on the assumption that you have a rudimentary understanding of personal computer (PC) operations using Disk Operating System (DOS) versionmore » 2.0 or greater (IBM 1984). You should know how to create subdirectories and get around the subdirectory tree.« less

  14. Magnetism, structures and stabilities of cluster assembled TM@Si nanotubes (TM = Cr, Mn and Fe): a density functional study.

    PubMed

    Dhaka, Kapil; Bandyopadhyay, Debashis

    2016-08-02

    The present study reports transition metal (TM = Cr, Mn and Fe) doped silicon nanotubes with tunable band structures and magnetic properties by careful selection of cluster assemblies as building blocks using the first-principles density functional theory. We found that the transition metal doping and in addition, the hydrogen termination process can stabilize the pure silicon nanoclusters or cluster assemblies and then it could be extended as magnetic nanotubes with finite magnetic moments. Study of the band structures and density of states (DOS) of different empty and TM doped nanotubes (Type 1 to Type 4) show that these nanotubes are useful as metals, semiconductors, semi-metals and half-metals. These designer magnetic materials could be useful in spintronics and magnetic devices of nanoscale order.

  15. M S MOLECULARES Rumo aos limites da miniaturiza o - (Molecular Magnets - towards the limits of miniaturization)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Reis, Mario S; Moreira Dos Santos, Antonio F

    Por s culos, acreditou-se que o magnetismo s se manifestava em metais, como aqueles contendo ferro; hoje, a imagem mais comum de um m talvez seja a daquelas plaquinhas flex veis coladas geladeira com propagandas dos mais diversos tipos. O leitor conseguiria imaginar um material puramente org nico daqueles que formam os seres vivos como magn tico? E m s do tamanho de mol culas? fato: ambos existem. Esses novos materiais, conhecidos como magnetos moleculares, descobertos e desenvolvidos em v rios laborat rios do mundo, j re nem longa lista de aplica es, do tratamento do c ncer a refrigeradoresmore » ecol gicos, passando pela transmiss o de eletricidade sem perda de calor e a fabrica o de computadores extremamente velozes.« less

  16. COMGEN - A PROGRAM FOR GENERATING FINITE ELEMENT MODELS OF COMPOSITE MATERIALS AT THE MICRO LEVEL (SGI IRIS VERSION)

    NASA Technical Reports Server (NTRS)

    Melis, M. E.

    1994-01-01

    A significant percentage of time spent in a typical finite element analysis is taken up in the modeling and assignment of loads and constraints. This process not only requires the analyst to be well-versed in the art of finite element modeling, but also demands familiarity with some sort of preprocessing software in order to complete the task expediently. COMGEN (COmposite Model GENerator) is an interactive FORTRAN program which can be used to create a wide variety of finite element models of continuous fiber composite materials at the micro level. It quickly generates batch or "session files" to be submitted to the finite element pre- and post-processor program, PATRAN. (PDA Engineering, Costa Mesa, CA.) In modeling a composite material, COMGEN assumes that its constituents can be represented by a "unit cell" of a fiber surrounded by matrix material. Two basic cell types are available. The first is a square packing arrangement where the fiber is positioned in the center of a square matrix cell. The second type, hexagonal packing, has the fiber centered in a hexagonal matrix cell. Different models can be created using combinations of square and hexagonal packing schemes. Variations include two- and three- dimensional cases, models with a fiber-matrix interface, and different constructions of unit cells. User inputs include fiber diameter and percent fiber-volume of the composite to be analyzed. In addition, various mesh densities, boundary conditions, and loads can be assigned to the models within COMGEN. The PATRAN program then uses a COMGEN session file to generate finite element models and their associated loads which can then be translated to virtually any finite element analysis code such as NASTRAN or MARC. COMGEN is written in FORTRAN 77 and has been implemented on DEC VAX series computers under VMS and SGI IRIS series workstations under IRIX. If the user has the PATRAN package available, the output can be graphically displayed. Without PATRAN, the output is tabular. The VAX VMS version is available on a 5.25 inch 360K MS-DOS format diskette (standard distribution media) or a 9-track 1600 BPI DEC VAX FILES-11 format magnetic tape, and it requires about 124K of main memory. The standard distribution media for the IRIS version is a .25 inch streaming magnetic tape cartridge in UNIX tar format. The memory requirement for the IRIS version is 627K. COMGEN was developed in 1990. DEC, VAX and VMS are trademarks of Digital Equipment Corporation. PATRAN is a registered trademark of PDA Engineering. SGI IRIS and IRIX are trademarks of Silicon Graphics, Inc. MS-DOS is a registered trademark of Microsoft Corporation. UNIX is a registered trademark of AT&T.

  17. [Slaves and citizens on Ilha Grande: the dawning of the Republic came slowly].

    PubMed

    Schnoor, Eduardo Cavalcanti

    2012-12-01

    The article introduces Ilha Grande, a district in the municipality of Angra dos Reis, and describes its role within the subsistence market economy and the memory of slavery as found in the Angra dos Reis Civil Records. According to the Almanaque Laemmert, this district had the largest number of slaves in the municipality as of the 1870s. Most owners had few slaves, and the majority of landholdings were small. The Angra dos Reis Civil Records did not forget slavery after May 1888. A number of birth and death notifications describe the persons in question as former slaves. Even in the twentieth century, clerks continued to describe various republican citizens as ex-slaves.

  18. Perspectivas Futuras para o Observatório do Pico dos Dias

    NASA Astrophysics Data System (ADS)

    Bruch, Albert

    2004-02-01

    Com o Observatório Gemini plenamente operacional e o telescópio SOAR iniciando suas operações em breve, a astronomia observacional brasileira encontra-se no auge de uma transformação profunda que terá um impacto grave no Observatório do Pico dos Dias - OPD. Refletimos aqui sobre a natureza desse impacto e estratégias para manter a competitividade do OPD. Não queremos apresentar receitas prontas, mas idéias que poderão servir como base de discussão sobre o uso inteligente dos telescópios do OPD como parte do conjunto de instrumentos disponíveis à comunidade astronômica brasileira.

  19. Coulomb gap: how a metal film becomes an insulator

    PubMed

    Butko; DiTusa; Adams

    2000-02-14

    Electron tunneling measurements of the density of states (DOS) in ultrathin Be films reveal that a correlation gap mediates their insulating behavior. In films with sheet resistance R<5000 Omega the correlation singularity appears as the usual perturbative ln(V) zero bias anomaly (ZBA) in the DOS. As R is increased further, however, the ZBA grows and begins to dominate the DOS spectrum. This evolution continues until a nonperturbative |V| Efros-Shklovskii Coulomb gap spectrum finally emerges in the highest R films. Transport measurements of films which display this gap are well described by a universal variable range hopping law R(T) = (h/2e(2))exp(T0/T)(1/2).

  20. Measuring Student Learning in Social Justice Courses: The Diversity and Oppression Scale

    ERIC Educational Resources Information Center

    Windsor, Liliane Cambraia; Shorkey, Clay; Battle, DuWayne

    2015-01-01

    The Diversity and Oppression Scale (DOS) is a standardized instrument measuring self-reported student learning about diversity and oppression based on requirements of the Council on Social Work Education. DOS was tested with social work students in 2 major North American universities. Factor structure was examined using exploratory factor analysis…

  1. Clearing a Path: The 16-Bit Operating System Jungle Offers Confusion, Not Standardization.

    ERIC Educational Resources Information Center

    Pournelle, Jerry

    1984-01-01

    Discusses the design and limited uses of the Pascal, MS-DOS, CP/M, and PC-DOS operating systems as standard operating systems for 16-bit microprocessors, especially with the more sophisticated microcomputers currently being developed. Advantages and disadvantages of Unix--a multitasking, multiuser operating system--as a standard operating system…

  2. 78 FR 19077 - Forwarding of Asylum Applications to the Department of State

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-29

    ... Department of State (DOS), Bureau of Democracy, Human Rights, and Labor. Currently, EOIR forwards to DOS all... form of post-traumatic stress or depression that affects long-term memory, making credibility... time of dwindling resources, both human and monetary, the Department has determined that it is best to...

  3. 8 CFR 212.6 - Border crossing identification cards.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... or pleasure without a visa and passport, must apply to the DOS on Form DS-156, Visitor Visa... border crossing card (or similar stamp in a passport). (i) A Canadian citizen or other person sharing... crossing card (or similar stamp in a passport) issued by the DOS prior to April 1, 1998, that does not...

  4. 8 CFR 212.6 - Border crossing identification cards.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... or pleasure without a visa and passport, must apply to the DOS on Form DS-156, Visitor Visa... border crossing card (or similar stamp in a passport). (i) A Canadian citizen or other person sharing... crossing card (or similar stamp in a passport) issued by the DOS prior to April 1, 1998, that does not...

  5. 8 CFR 212.6 - Border crossing identification cards.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... or pleasure without a visa and passport, must apply to the DOS on Form DS-156, Visitor Visa... border crossing card (or similar stamp in a passport). (i) A Canadian citizen or other person sharing... crossing card (or similar stamp in a passport) issued by the DOS prior to April 1, 1998, that does not...

  6. 8 CFR 212.6 - Border crossing identification cards.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... or pleasure without a visa and passport, must apply to the DOS on Form DS-156, Visitor Visa... border crossing card (or similar stamp in a passport). (i) A Canadian citizen or other person sharing... crossing card (or similar stamp in a passport) issued by the DOS prior to April 1, 1998, that does not...

  7. 8 CFR 212.6 - Border crossing identification cards.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... or pleasure without a visa and passport, must apply to the DOS on Form DS-156, Visitor Visa... border crossing card (or similar stamp in a passport). (i) A Canadian citizen or other person sharing... crossing card (or similar stamp in a passport) issued by the DOS prior to April 1, 1998, that does not...

  8. Entre Dos Mundos/Between Two Worlds: Youth Violence Prevention for Acculturating Latino Families

    ERIC Educational Resources Information Center

    Smokowski, Paul R.; Bacallao, Martica

    2009-01-01

    Objective: This study evaluated the efficacy of Entre Dos Mundos/Between Two Worlds (EDM) prevention for Latino adolescents. Method: In an experimental trial to compare implementation formats, 41 Latino families were randomly assigned to EDM action-oriented skills training groups, and 47 families were randomly assigned to unstructured EDM support…

  9. Computer-Assisted Instruction to Teach DOS Commands: A Pilot Study.

    ERIC Educational Resources Information Center

    McWeeney, Mark G.

    1992-01-01

    Describes a computer-assisted instruction (CAI) program used to teach DOS commands. Pretest and posttest results for 65 graduate students using the program are reported, and it is concluded that the CAI program significantly aided the students. Sample screen displays for the program and several questions from the pre/posttest are included. (nine…

  10. "DOS for Managers." Management Training Series.

    ERIC Educational Resources Information Center

    Marion County Schools, Fairmont, WV.

    A plan is provided for a lesson on disk operating systems (DOS) for managers. Twenty-five lesson objectives are listed, followed by suggestions for learning activities and special resources. In the presentation section, key points and content are provided for 25 instructional topics that correspond to the 25 lesson objectives. The topics are as…

  11. Yours, Mine or Ours: What Counts as Innovation?

    ERIC Educational Resources Information Center

    Cooksey, Ray W.

    2011-01-01

    In this paper, I argue that research and development organizations (R&DOs) have particular perspectives on what counts as an innovation whereas the potential adopting users usually have quite different often diverse perspectives. If these "worldviews" do not overlap or speak to each other, then what R&DOs consider innovative might constitute a…

  12. Microbial contamination of dental unit waterlines and effect on quality of indoor air.

    PubMed

    Kadaifciler, Duygu Göksay; Cotuk, Aysin

    2014-06-01

    The microbiological quality in dental unit waterlines (DUWLs) is considered to be important because patients and dental staff with suppressed immune systems are regularly exposed to water and aerosols generated from dental units (DUs). Opportunistic pathogens like Pseudomonas, Legionella, Candida, and Aspergillus can be present in DUWLs, while during consultations, bioaerosols can be dispersed in the air, thus resulting in effects on microbiological quality of indoor air. This present study represents microbiological air and water quality in dental offices (DOs) and also concerns the relationship between the quality of DO air and dental unit water. This study aimed to assess both the microbial quality of dental unit water and the indoor air in 20 DOs and to survey the effect on the quality of the indoor air with the existing microorganisms in dental unit water. Fourteen out of 20 (70 %) DUWLs were found to be contaminated with a high number of aerobic mesophilic heterotrophic bacteria. In terms of bacterial air contamination levels, in 90 % of DOs, a medium level (<500 colony-forming units (CFU)/m(3)) of contamination was determined, while in terms of microfungal air contamination, in all DOs, a low level (<100 CFU/m(3)) of contamination was determined. Potential infection or allergen agents, such as Pseudomonas, Micrococcus, Staphylococcus, Alternaria, Cladosporium, Penicillium, Aspergillus, and Paecilomyces were isolated from water and air samples. This study's determination of contamination sources and evaluation of microbial load in DOs could contribute to the development of quality control methods in the future.

  13. Sedimentation survey of Lago Dos Bocas, Utuado, Puerto Rico, January 2010

    USGS Publications Warehouse

    Soler-López, Luis R.

    2014-01-01

    Lago Dos Bocas reservoir was completed in 1942 to provide water for hydroelectric power generation along the northern coast of Puerto Rico. The reservoir had an original storage capacity of 37.50 million cubic meters (Mm3). The dam is located about 9 kilometers (km) northeast of the town of Utuado, immediately downstream of the original confluence of the Río Grande de Arecibo and the Río Caonillas (fig. 1). The Puerto Rico Electric Power Authority (PREPA) owns and operates the Lago Dos Bocas reservoir, and since 1996, the reservoir has become an essential part of the Puerto Rico Aqueduct and Sewer Authority (PRASA) North Coast Superaqueduct Project. The Superaqueduct is supplied by controlled releases for hydroelectric power generation that replenish the public-supply raw-water intake pool located about 10 km downstream from the Lago Dos Bocas Dam (fig. 1). As of 2005, the Superaqueduct supplies about 4.03 cubic meters per second (m3/s) (348,192 cubic meters per day [m3/d]) of potable water to communities along the northern coast, from Arecibo to the San Juan metropolitan area. Because of the importance of the reservoir to the North Coast Superaqueduct, the U.S. Geological Survey (USGS), in cooperation with PRASA, conducted a sedimentation survey of Lago Dos Bocas in January 2009. The results of this survey were used to estimate the useful life and the firm yield of the reservoir, and evaluate the need to dredge the reservoir.

  14. Transport and NMR characteristics of the skutterudite-related compound Ca3Rh4Sn13

    NASA Astrophysics Data System (ADS)

    Tseng, C. W.; Kuo, C. N.; Li, B. S.; Wang, L. M.; Gippius, A. A.; Kuo, Y. K.; Lue, C. S.

    2018-02-01

    We report the electronic properties of the Yb3Rh4Sn13-type single crystalline Ca3Rh4Sn13 by means of the electrical resistivity, Hall coefficient, Seebeck coefficient, thermal conductivity, as well as 119Sn nuclear magnetic resonance (NMR) measurements. The negative sign of the Hall coefficient and Seebeck coefficient at low temperatures suggests that the n-type carriers dominate the electrical transport in Ca3Rh4Sn13, in contrast to the observations in Sr3Rh4Sn13 which has a p-type conduction. Such a finding indicates a significant difference in the electronic features between these two stannides. Furthermore, we analyzed the temperature-dependent 119Sn NMR spin-lattice relaxation rate for Ca3Rh4Sn13, (Sr0.7Ca0.3)3Rh4Sn13, and Sr3Rh4Sn13 to examine the change of the electronic Fermi-level density of states (DOS) in (Sr1-xCax)3Rh4Sn13. It indicates that the Sn 5s partial Fermi-level DOS enhances with increasing the Ca content, being consistent with the trend of the superconducting temperature. Since the total Fermi-level DOS usually obeys the same trend of the partial Fermi-level DOS, the NMR analysis provides microscopic evidence for the correlation between the electronic DOS and superconductivity of the (Sr1-xCax)3Rh4Sn13 system.

  15. Como os Alunos do Ensino Médio da Rede Estadual de São Paulo obtém Conhecimentos Astronômicos?

    NASA Astrophysics Data System (ADS)

    da Cunha, W. S.; Voelzke, M. R.; Amaral, L. H.

    2005-08-01

    Atualmente vivencia-se um mundo globalizado onde os computadores e a internet permitiram um acesso rápido e seguro a todo tipo de informação e conhecimento. O presente trabalho visa analisar a maneira pela qual alunos de segundo grau da rede estadual da cidade de São Paulo obtiveram, caso tenham, conhecimentos básicos de astronomia quanto aos fenômenos celestes que os rodeiam, tais como a sucessão dos dias e das estações do ano, além de questioná~los sobre fatos genéricos tais como: o que vem a ser o Sol, o Big Bang, o que ocasionou a extinção dos dinossauros. Para tanto foi elaborado um formulário constando de questões de múltipla escolha, o qual foi aplicado no primeiro colegial diurno da Escola Estadual Guilherme de Almeida. Num espaço amostral de 44 alunos constatou-se que 41% dos alunos adquiriram seus conhecimentos astronômicos na escola e 59% através da mídia em geral. Neste mesmo espaço amostral apenas 11% dos alunos usaram computadores na escola, 41% na residência, 5% no trabalho e 43% não utilizaram. O presente estudo revelou também que para 50% dos alunos o professor jamais utilizou um programa de computador a respeito de astronomia ou fez alguma apresentação sobre o tema. Embora em sua fase inicial este estudo revela claramente que a maioria dos alunos não obtém na escola seus conhecimentos astronômicos, estes provém de fontes não especificamente didático-pedagógicas tais como filmes e revistas populares que não raramente geram conhecimentos incompletos e em muitos casos inclusive falhos.

  16. Role of the treating surgeon in the consent process for elective refractive surgery.

    PubMed

    Schallhorn, Steven C; Hannan, Stephen J; Teenan, David; Schallhorn, Julie M

    2016-01-01

    To compare patient's perception of consent quality, clinical and quality-of-life outcomes after laser vision correction (LVC) and refractive lens exchange (RLE) between patients who met their treating surgeon prior to the day of surgery (PDOS) or on the day of surgery (DOS). Retrospective, comparative case series. Optical Express, Glasgow, UK. Patients treated between October 2015 and June 2016 (3972 LVC and 979 RLE patients) who attended 1-day and 1-month postoperative aftercare and answered a questionnaire were included in this study. All patients had a thorough preoperative discussion with an optometrist, watched a video consent, and were provided with written information. Patients then had a verbal discussion with their treating surgeon either PDOS or on the DOS, according to patient preference. Preoperative and 1-month postoperative visual acuity, refraction, preoperative, 1-day and 1-month postoperative questionnaire were compared between DOS and PDOS patients. Multivariate regression model was developed to find factors associated with patient's perception of consent quality. Preoperatively, 8.0% of LVC and 17.1% of RLE patients elected to meet their surgeon ahead of the surgery day. In the LVC group, 97.5% of DOS and 97.2% of PDOS patients indicated they were properly consented for surgery ( P =0.77). In the RLE group, 97.0% of DOS and 97.0% of PDOS patients stated their consent process for surgery was adequate ( P =0.98). There was no statistically significant difference between DOS and PDOS patients in most of the postoperative clinical or questionnaire outcomes. Factors predictive of patient's satisfaction with consent quality were postoperative satisfaction with vision (46.7% of explained variance), difficulties with night driving, close-up vision or outdoor/sports activities (25.4%), visual phenomena (12.2%), dry eyes (7.5%), and patient's satisfaction with surgeon's care (8.2%). Perception of quality of consent was comparable between patients that elected to meet the surgeon PDOS, and those who did not.

  17. Elderly with knee osteoarthritis should perform nutritional assessment: integrative literature review.

    PubMed

    Souza, Isabelle Ferreira da Silva; Oliveira Neta, Rosa Sá de; Gazzola, Juliana Maria; Souza, Marcelo Cardoso de

    2017-01-01

    To review scientific literature to assess nutritional status of elderly patients with osteoarthritis in the last 16 years. This is an integrative literature review that included articles published in national and international journals indexed in PubMed, SciELO and BIREME. We selected 14 articles, and English language was predominant. The year of publication of articles ranged from 2006 to 2016, and most of papers were cross-sectional studies. To gather papers and for posterior evaluate, we used a validated data collection instrument and the included studies were critical analyzed by reading, gathering and analysis of articles. Studies suggested that there is a positive correlation between obesity and knee osteoarthritis. Obesity is one of the most important modifiable factors in worsening of osteoarthritis symptoms. RESUMO O objetivo da pesquisa foi revisar a produção científica referente à avaliação do estado nutricional de idosos com osteoartrite nos últimos 16 anos. Assim, o estudo foi uma revisão integrativa da literatura, realizada com a busca de artigos publicados em periódicos nacionais e internacionais indexados no PubMed, na SciELO e na BIREME. Foram selecionados 14 artigos, e o idioma inglês foi preponderante. O período de publicação dos artigos variou de 2006 a 2016, com predominância de estudos do tipo transversais. Para reunir os artigos e para posterior avaliação, foi utilizado um instrumento de coleta de dados validado, e as análises críticas dos estudos incluídos foram realizadas por meio da leitura, do agrupamento e da análise dos artigos. As pesquisas sugeriram que existe correlação positiva entre obesidade e osteoartrite de joelhos. Além disto, a obesidade é um dos fatores mais significativos e modificáveis no agravamento dos sintomas da osteoartrite.

  18. Percepção Astronômica de Alunos do Ensino Médio da Rede Estadual de São Paulo

    NASA Astrophysics Data System (ADS)

    de Oliveira, E. F.; Voelzke, M. R.; Amaral, L. H.

    2005-08-01

    Embora a astronomia seja uma das ciências mais antigas da humanidade e muitos dos conceitos astronômicos serem populares, principalmente nesta época de alta globalização do conhecimento por intermédio de eficientes meios de comunicação e de obtenção da informação, notadamente através da internet, observa-se que uma parcela significativa dos estudantes encontra-se à margem dessas informações. O presente trabalho visa analisar o nível de conhecimento básico dos alunos de Ensino Médio da rede estadual da cidade de Suzano quanto aos fenômenos astronômicos que os rodeiam, tais como a sucessão dos dias e das estações do ano, além de questioná-los sobre fatos genéricos tais como: quais são os astros que se encontram mais próximos do planeta Terra, o que vem a ser o Sol, o Big Bang, um ano-luz, uma estrela cadente, a estrela de Bélem e o que ocasionou a extinção dos dinossauros. Para tanto foi elaborado um formulário constando de questões de múltipla escolha, o qual foi aplicado no primeiro colegial noturno da Escola Estadual Batista Renzi. Num espaço amostral de 34 alunos constatou-se que apenas 29,4% compreendiam a sucessão dos dias da semana, que apenas 20,6% explicaram corretamente as estações do ano, que apenas 20,6% tinham idéia de quais são os objetos celestes mais próximos da Terra, em contraposição 67,6% sabiam classificar corretamente o Sol como estrela, 55,9% relacionavam o Big Bang à origem do universo, apenas 20,6% identificavam um ano-luz como unidade de distância, 32,4% reconheciam uma estrela cadente como meteoro, 41,2% consideravam a estrela de Belém como um cometa e 50,0% explicaram corretamente a extinção dos dinossauros. A presente análise será expandida para as demais classes de primeiro colegial, não somente do período noturno, mas também do diurno da Escola Estadual Batista Renzi, bem como o formulário será devidamente ampliado. Já nesta primeira fase nota-se claramente o pequeno discernimento de eventos astronômicos dos alunos e principalmente a grande confusão sobre o significado correto de termos astronômicos populares.

  19. Analysis of astronomy knowledge of the students in the Federal Institute Sao Paulo

    NASA Astrophysics Data System (ADS)

    Moraes, A. C.; Voelzke, M. R.

    2014-08-01

    Este trabalho é parte integrante da pesquisa de mestrado acadêmico em ensino de ciências. Nele, busca-se apresentar os resultados da pesquisa realizada entre os 106 alunos do curso superior de tecnologia em automação industrial do Instituto Federal de Educação, Ciência e Tecnologia de São Paulo campus Cubatão, divididos em cinco turmas, duas no período matutino e três no período noturno. A análise dos resultados deste pré questionárioconstatou a falta de conhecimento básico dos discentes, sobre assuntos relacionados à astronomia, o que pode ser atribuído ao ineficiente processo de aprendizado pelo qual eles passaram tanto no ensino médio como no ensino fundamental, em escolas municipais, estaduais e particulares onde estudaram. No ensino de astronomia, têm-se diagnosticado constantemente diversas dificuldades conceituais tanto por parte de alunos como de professores de todas as áreas e níveis de ensino e poucos de fato a compreendem (ALBRECHT; VOELZKE, 2010). Demonstra-se as duas etapas concluídas do trabalho. A primeira etapa indica a análise dos conhecimentos prévios sobre conceitos astronômicos, através do questionário com 25 perguntas. A fim de corrigir as falhas constatadas, experimentalmente ministrou-se, externo ao conteúdo programático, um curso básico em astronomia, com diferentes estratégias de ensino, tais como, utilização de aulas expositivas dialogadas, recursos audiovisuais e palestras, para corrigir as dificuldades diagnosticadas. Essas estratégias de ensino se comprovaram adequadas às necessidades dos alunos e os conceitos foram finalmente compreendidos. Ao término do curso, completado o interstício de 120 dias, para caracterizar que houve a aprendizagem significativa, realizou-se uma nova pesquisa, quando, exatamente os mesmos 106 alunos responderam as mesmas 25 questões aplicadas na primeira etapa. Constata-se na segunda etapa, após análise, que em todas as questões, houve maior compreensão dos assuntos abordados e os alunos obtiveram uma melhora significativa no aprendizado dos conceitos relacionados à astronomia. Nota-se que a astronomia está presente e é elemento importante dos parâmetros curriculares nacionais e que há muito interesse por parte dos alunos com relação ao tema. Diante dos resultados obtidos no pós-curso, pode-se afirmar que o curso básico em astronomia, realizado na própria escola, mas externo ao conteúdo programático, proporcionou uma integração entre os alunos, estreitando os laços de amizade e do conhecimento entre eles não importando a turma ou o período pois a dificuldade inicial foi vencida por todos, com muita dedicação e comprometimento entre todos; hoje estes alunos podem seguramente continuar estudando estes conceitos de astronomia. ALBRECHT, E.; VOELZKE, M. R.Teaching of Astronomy and scientific literacy. Journal of Science Education, v. 11, n. 1, p.35-38, 2010.

  20. Cardiac Amyloidosis and its New Clinical Phenotype: Heart Failure with Preserved Ejection Fraction.

    PubMed

    Mesquita, Evandro Tinoco; Jorge, Antonio José Lagoeiro; Souza, Celso Vale; Andrade, Thais Ribeiro de

    2017-07-01

    Heart failure with preserved ejection fraction (HFpEF) is now an emerging cardiovascular epidemic, being identified as the main phenotype observed in clinical practice. It is more associated with female gender, advanced age and comorbidities such as hypertension, diabetes, obesity and chronic kidney disease. Amyloidosis is a clinical disorder characterized by the deposition of aggregates of insoluble fibrils originating from proteins that exhibit anomalous folding. Recently, pictures of senile amyloidosis have been described in patients with HFpEF, demonstrating the need for clinical cardiologists to investigate this etiology in suspect cases. The clinical suspicion of amyloidosis should be increased in cases of HFPS where the cardio imaging methods are compatible with infiltrative cardiomyopathy. Advances in cardio imaging methods combined with the possibility of performing genetic tests and identification of the type of amyloid material allow the diagnosis to be made. The management of the diagnosed patients can be done in partnership with centers specialized in the study of amyloidosis, which, together with the new technologies, investigate the possibility of organ or bone marrow transplantation and also the involvement of patients in clinical studies that evaluate the action of the new emerging drugs. Resumo A insuficiência cardíaca com fração de ejeção preservada (ICFEP) é hoje uma epidemia cardiovascular emergente, sendo identificada como o principal fenótipo observado na prática clínica. Está mais associado ao sexo feminino, idade avançada e a comorbidades como hipertensão arterial, diabetes, obesidade e doença renal crônica. A amiloidose é uma desordem clínica caracterizada pelo depósito de agregados de fibrilas insolúveis originadas de proteínas que apresentam dobramento anômalo. Recentemente, têm sido descritos quadros de amiloidose senil em pacientes com ICFEP, demonstrando a necessidade de os cardiologistas clínicos investigarem esta etiologia em casos suspeitos. Deve-se aumentar a suspeição clínica de amiloidose diante dos casos de ICFEP onde os métodos de cardioimagem sejam compatíveis com o quadro de cardiomiopatia infiltrativa. Os avanços nos métodos de cardioimagem aliados à possibilidade de realização de testes genéticos e identificação do tipo do material amiloide permitem a realização do diagnóstico. O manejo dos pacientes diagnosticados pode ser feito em parceria com centros especializados no estudo de amiloidose, que, aliados às novas tecnologias, investigam a possibilidade de transplante de órgãos ou medula óssea e também o envolvimento dos pacientes em estudos clínicos que avaliam a ação das novas drogas emergentes.

  1. Fiscal Year 2011 Afghanistan Infrastructure Fund Projects Are Behind Schedule and Lack Adequate Sustainment Plans

    DTIC Science & Technology

    2012-07-30

    interconnected subset ofUSATD Economic Support Fund ( ESl -") projects, which arc essential to meet program ol~jcctives. Under the program, DOS and US AID...with conunent: The congressional reporting requirements in the KDAA cover AIF funded projects, whether executed hy DoD or DOS. ESl ’-tunded projects

  2. Tunneling study of cavity grade Nb : possible magnetic scattering at the surface.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Prolier, T.; Zasadzinski, J. F.; Cooley, L.

    Tunneling spectroscopy was performed on Nb pieces prepared by the same processes used to etch and clean superconducting radio frequency (SRF) cavities. Air exposed, electropolished Nb exhibited a surface superconducting gap {Delta} = 1.55 meV, which is characteristic of a clean, bulk Nb. However, the tunneling density of states (DOS) was significantly broadened. The Nb pieces, which were treated with the same mild baking used to improve the Q slope in SRF cavities, reveal a sharper DOS. Good fits to the DOS were obtained by using the Shiba theory, suggesting that magnetic scattering of quasiparticles is the origin of themore » gapless surface superconductivity and a heretofore unrecognized contributor to the Q-slope problem of Nb SRF cavities.« less

  3. Carbohydrates in diversity-oriented synthesis: challenges and opportunities.

    PubMed

    Lenci, E; Menchi, G; Trabocchi, A

    2016-01-21

    Over the last decade, Diversity-Oriented Synthesis (DOS) has become a new paradigm for developing large collections of structurally diverse small molecules as probes to investigate biological pathways, and to provide a larger array of the chemical space. Drug discovery and chemical biology are taking advantage of DOS approaches to exploit highly-diverse and complex molecular platforms, producing advances in both target and ligand discovery. In this view, carbohydrates are attractive building blocks for DOS libraries, due to their stereochemical diversity and high density of polar functional groups, thus offering many possibilities for chemical manipulation and scaffold decoration. This review will discuss research contributions and perspectives on the application of carbohydrate chemistry to explore the accessible chemical space through appendage, stereochemical and scaffold diversity.

  4. Rational design of mixed ionic and electronic conducting perovskite oxides for solid oxide fuel cell anode materials: A case study for doped SrTiO3

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Suthirakun, Suwit; Xiao, Guoliang; Ammal, Salai Cheettu

    2014-01-01

    The effect of p- and n-type dopants on ionic and electronic conductivity of SrTiO3 based perovskites were investigated both computationally and experimentally. Specifically, we performed density functional theory (DFT) calculations of Na- and La-doped SrTiO3 and Na- and Nb-doped SrTiO3 systems. Constrained ab initio thermodynamic calculations were used to evaluate the phase stability and reducibility of doped SrTiO3 under both oxidizing and reducing synthesis conditions, as well as under anodic solid oxide fuel cell (SOFC) conditions. The density of states (DOS) of these materials was analyzed to study the effects of p- and n-doping on the electronic conductivity. Furthermore, Na-more » and La-doped SrTiO3 and Na- and Nb-doped SrTiO3 samples were experimentally prepared and the conductivity was measured to confirm our computational predictions. The experimental observations are in very good agreement with the theoretical predictions that doping n-doped SrTiO3 with small amounts of p-type dopants promotes both the ionic and electronic conductivity of the material. This doping strategy is valid independent of p- and n-doping site and permits the synthesis of perovskite based mixed ionic/electronic conductors.« less

  5. Anyon Superconductivity of Sb

    NASA Astrophysics Data System (ADS)

    Maksoed, Wh-; Parengkuan, August

    2016-10-01

    In any permutatives to Pedro P. Kuczhynski from Peru, for anyon superconductivity sought EZ Kuchinskii et al.: ``Anion height dependence of Tc & d.o.s of Fe-based Superconductors'', 2010 as well as ``on the basis of electron microscopy & AFM measurements, these phenomena are quantified with focus on fractal dimension, particle perimeter & size of the side branch(tip width) in bert Stegemann et al.:Crystallization of Sb nanoparticles-Pattern Formation & Fractal Growth'', J.PhysChem B., 2004. For dendritic & dendrimer fractal characters shown further: ``antimony denrites were found to be composed of well-crystallized nanoflakes with size 20-4 nm''- Bou Zhau, et al., MaterialLetters, 59 (2005). The alkyl triisopropyl attached in TIPSb those includes in DNA, haemoglobin membrane/fixed-bed reactor for instance quotes in Dragony Fu, Nature Review Cancer, 12 (Feb 2012). Heartfelt Gratitudes to HE. Mr. Prof. Ir. Handojo.

  6. Self assembly of organic nanostructures and dielectrophoretic assembly of inorganic nanowires.

    NASA Astrophysics Data System (ADS)

    Dholakia, Geetha; Kuo, Steven; Allen, E. L.

    2007-03-01

    Self assembly techniques enable the organization of organic molecules into nanostructures. Currently engineering strategies for efficient assembly and routine integration of inorganic nanoscale objects into functional devices is very limited. AC Dielectrophoresis is an efficient technique to manipulate inorganic nanomaterials into higher dimensional structures. We used an alumina template based sol-gel synthesis method for the growth of various metal oxide nanowires with typical diameters of 100-150 nm, ranging in length from 3-10 μm. Here we report the dielectrophoretic assembly of TiO2 nanowires, an important material for photocatalysis and photovoltaics, onto interdigitated devices. Self assembly in organic nanostructures and its dependence on structure and stereochemistry of the molecule and dielectrophoretic field dependence in the assembly of inorganic nanowires will be compared and contrasted. Tunneling spectroscopy and DOS of these nanoscale systems will also be discussed.

  7. Trap density of states in n-channel organic transistors: variable temperature characteristics and band transport

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cho, Joung-min, E-mail: cho.j.ad@m.titech.ac.jp; Akiyama, Yuto; Kakinuma, Tomoyuki

    2013-10-15

    We have investigated trap density of states (trap DOS) in n-channel organic field-effect transistors based on N,N ’-bis(cyclohexyl)naphthalene diimide (Cy-NDI) and dimethyldicyanoquinonediimine (DMDCNQI). A new method is proposed to extract trap DOS from the Arrhenius plot of the temperature-dependent transconductance. Double exponential trap DOS are observed, in which Cy-NDI has considerable deep states, by contrast, DMDCNQI has substantial tail states. In addition, numerical simulation of the transistor characteristics has been conducted by assuming an exponential trap distribution and the interface approximation. Temperature dependence of transfer characteristics are well reproduced only using several parameters, and the trap DOS obtained from the simulatedmore » characteristics are in good agreement with the assumed trap DOS, indicating that our analysis is self-consistent. Although the experimentally obtained Meyer-Neldel temperature is related to the trap distribution width, the simulation satisfies the Meyer-Neldel rule only very phenomenologically. The simulation also reveals that the subthreshold swing is not always a good indicator of the total trap amount, because it also largely depends on the trap distribution width. Finally, band transport is explored from the simulation having a small number of traps. A crossing point of the transfer curves and negative activation energy above a certain gate voltage are observed in the simulated characteristics, where the critical V{sub G} above which band transport is realized is determined by the sum of the trapped and free charge states below the conduction band edge.« less

  8. Tunneling conductance in superconductor-hybrid double quantum dots Josephson junction

    NASA Astrophysics Data System (ADS)

    Chamoli, Tanuj; Ajay

    2018-05-01

    The present work deals with the theoretical model study to analyse the tunneling conductance across a superconductor hybrid double quantum dots tunnel junction (S-DQD-S). Recently, there are many experimental works where the Josephson current across such nanoscopic junction is found to be dependent on nature of the superconducting electrodes, coupling of the hybrid double quantum dot's electronic states with the electronic states of the superconductors and nature of electronic structure of the coupled dots. For this, we have attempted a theoretical model containing contributions of BCS superconducting leads, magnetic coupled quantum dot states and coupling of superconducting leads with QDs. In order to include magnetic coupled QDs the contributions of competitive Kondo and Ruderman-Kittel- Kasuya-Yosida (RKKY) interaction terms are also introduced through many body effects in the model Hamiltonian at low temperatures (where Kondo temperature TK < superconducting transition temperature TC). Employing non-equilibrium Green's function approach within mean field approximation, we have obtained expressions for density of states (DOS) and analysed the same using numerical computation to underline the nature of DOS close to Fermi level in S-DQD-S junctions. On the basis of numerical computation, it is pointed out that indirect exchange interaction between impurities (QD) i.e. RKKY interaction suppresses the screening of magnetic QD due to Cooper pair electrons i.e. Kondo effect in the form of reduction in the magnitude of sharp DOS peak close to Fermi level which is in qualitative agreement with the experimental observations in such tunnel junctions. Tunneling conductance is proportional to DOS, hence we can analyse it's behaviour with the help of DOS.

  9. Hospital costs associated with surgical site infections in general and vascular surgery patients.

    PubMed

    Boltz, Melissa M; Hollenbeak, Christopher S; Julian, Kathleen G; Ortenzi, Gail; Dillon, Peter W

    2011-11-01

    Although much has been written about excess cost and duration of stay (DOS) associated with surgical site infections (SSIs) after cardiothoracic surgery, less has been reported after vascular and general surgery. We used data from the National Surgical Quality Improvement Program (NSQIP) to estimate the total cost and DOS associated with SSIs in patients undergoing general and vascular surgery. Using standard NSQIP practices, data were collected on patients undergoing general and vascular surgery at a single academic center between 2007 and 2009 and were merged with fully loaded operating costs obtained from the hospital accounting database. Logistic regression was used to determine which patient and preoperative variables influenced the occurrence of SSIs. After adjusting for patient characteristics, costs and DOS were fit to linear regression models to determine the effect of SSIs. Of the 2,250 general and vascular surgery patients sampled, SSIs were observed in 186 inpatients. Predisposing factors of SSIs were male sex, insulin-dependent diabetes, steroid use, wound classification, and operative time (P < .05). After adjusting for those characteristics, the total excess cost and DOS attributable to SSIs were $10,497 (P < .0001) and 4.3 days (P < .0001), respectively. SSIs complicating general and vascular surgical procedures share many risk factors with SSIs after cardiothoracic surgery. Although the excess costs and DOS associated with SSIs after general and vascular surgery are somewhat less, they still represent substantial financial and opportunity costs to hospitals and suggest, along with the implications for patient care, a continuing need for cost-effective quality improvement and programs of infection prevention. Copyright © 2011 Mosby, Inc. All rights reserved.

  10. 32 CFR Appendix C to Part 197 - Procedures for the Department of State (DoS) Foreign Relations of the United States (FRUS) Series

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 2 2012-07-01 2012-07-01 false Procedures for the Department of State (DoS) Foreign Relations of the United States (FRUS) Series C Appendix C to Part 197 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE (CONTINUED) MISCELLANEOUS HISTORICAL...

  11. 32 CFR Appendix C to Part 197 - Procedures for the Department of State (DoS) Foreign Relations of the United States (FRUS) Series

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 2 2013-07-01 2013-07-01 false Procedures for the Department of State (DoS) Foreign Relations of the United States (FRUS) Series C Appendix C to Part 197 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE (CONTINUED) MISCELLANEOUS HISTORICAL...

  12. 32 CFR Appendix C to Part 197 - Procedures for the Department of State (DoS) Foreign Relations of the United States (FRUS) Series

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 2 2014-07-01 2014-07-01 false Procedures for the Department of State (DoS) Foreign Relations of the United States (FRUS) Series C Appendix C to Part 197 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE (CONTINUED) MISCELLANEOUS HISTORICAL...

  13. The Challenges for Physicians of Demonstrating Continuing Competence in the Changing World of Medical Regulation: Osteopathic Pediatrician Case Report

    ERIC Educational Resources Information Center

    Langenau, Erik E.; Gimpel, John R.

    2012-01-01

    The current system of continuing medical education, maintenance of certification, and renewal of medical licenses can be quite burdensome and inefficient for all practicing physicians: medical doctors (M.D.s) and doctors of osteopathic medicine (D.O.s). D.O.s have opportunities for residency training and specialty certification which are not…

  14. 48 CFR 653.219-70 - DOS form DS-1910, Small Business Agency Review-Actions Above the Simplified Acquisition Threshold.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 4 2012-10-01 2012-10-01 false DOS form DS-1910, Small Business Agency Review-Actions Above the Simplified Acquisition Threshold. 653.219-70 Section 653.219-70... Threshold. As prescribed in 619.501(c), DS-1910 is prescribed for use in documenting set-aside decisions...

  15. A Visão do Universo Segundo a Concepção de um Grupo de Alunos do Ensino Médio de São Paulo

    NASA Astrophysics Data System (ADS)

    Araújo, M. A. A.; Elias, D. C. N.; Amaral, L. H.; Araújo, M. S. T.; Voelzke, M. R.

    2005-12-01

    Nesse trabalho foi identificada por meio de um questionário a visão de mundo sobre o Universo espaço e tempo entre 270 estudantes de Ensino Médio de três escolas de São Paulo. Constatou-se pouco conhecimento dos temas investigados sendo que apenas 20% dos alunos relacionaram as semanas com as fases da lua enquanto 28% associaram as estações do ano à inclinação do eixo de rotação da Terra e 23% tinham noções das distâncias entre objetos celestes próximos da Terra. Enquanto 56% conseguiram relacionar o Big Bang com a origem do Universo verificou-se que 37% reconheciam ano-luz como unidade de distância e 60% reconheciam o Sol como uma estrela. Apesar de 60% dos alunos indicarem a escola como principal fonte dos conhecimentos de astronomia seus conceitos ainda são inadequados havendo necessidade de aprimoramento da abordagem desses conteúdos pois apesar de popular a astronomia é veiculada de maneira pouco esclarecedora e com imprecissões.

  16. Life-cycle optimization model for distributed generation in buildings

    NASA Astrophysics Data System (ADS)

    Safaei, Amir

    O setor da construcao e responsavel por uma grande parte do consumo de energia e emissoes na Uniao Europeia. A Geracao Distribuida (GD) de energia, nomeadamente atraves de sistemas de cogeracao e tecnologias solares, representa um papel importante no futuro energetico deste setor. A otimizacao do funcionamento dos sistemas de cogeracao e uma tarefa complexa, devido as diversas variaveis em jogo, designadamente: os diferentes tipos de necessidades energeticas (eletricidade, aquecimento e arrefecimento), os precos dinamicos dos combustiveis (gas natural) e da eletricidade, e os custos fixos e variaveis dos diferentes sistemas de GD. Tal torna-se mais complexo considerando a natureza flutuante das tecnologias solares termicas e fotovoltaicas. Ao mesmo tempo, a liberalizacao do mercado da eletricidade permite exportar para a rede, a electricidade gerada localmente. Adicionalmente, a operacao estrategica de um sistema de GD deve atender aos quadros politicos nacionais, se tiver como objetivo beneficiar de tais regimes. Alem disso, considerando os elevados impactes ambientais do setor da construcao, qualquer avaliacao energetica de edificios rigorosa deve tambem integrar aspetos ambientais, utilizando uma abordagem de Ciclo de Vida (CV). Uma avaliacao de Ciclo de Vida (ACV) completa de um sistema de GD deve incluir as fases relativas a operacao e construcao do sistema, bem como os impactes associados a producao dos combustiveis. Foram analisadas as emissoes da producao de GN, as quais variam de acordo com a origem, tipo (convencional ou nao-convencional), e estado (na forma de GN Liquefeito (GNL) ou gas). Do mesmo modo, o impacte dos sistemas solares e afetado pela meteorologia e radiacao solar, de acordo com a sua localizacao geografica. Sendo assim, uma avaliacao adequada dos sistemas de GD exige um modelo de ACV adequado a localizacao geografica (Portugal), integrando tambem a producao de combustivel (GN), tendo em conta as suas diferentes fontes de abastecimento. O principal objetivo desta tese de doutoramento foi desenvolver um modelo para otimizar o desenho e operacao de sistemas de GD para o setor da construcao de edificios comerciais em Portugal, considerando os respetivos Impactes de Ciclo de Vida (IAVC) e Custos de Ciclo de Vida (CCV), de modo a satisfazer as necessidades energeticas do edificio. Tres tipos de tecnologias de cogeracao (Micro-Turbinas, Motores de combustao interna, e Celulas combustiveis de Oxido solido), e dois tipos de tecnologias de energia solar, solar termica e fotovoltaica, constituem os sistemas de GD que sao acoplados aos sistemas convencionais. Foi desenvolvido um modelo de CV, tendo em conta todos os impactes relacionados com a construcao e operacao dos sistemas de energia, bem como os processos a montante relacionados com a producao do GN. Em particular, o mix de GN consumido em Portugal em 2011 foi identificado (60% da Nigeria, 40% da Argelia) e os impactes relativos a cada uma das vias de abastecimento foram avaliados separadamente para quatro categorias de impacte ambiental: Consumo de Energia Primaria (CEP), Gases com Efeito de Estufa (GEE), acidificacao, e eutrofizacao. Devido a importancia das emissoes de GEE na formulacao de politicas, foi tambem realizada uma analise de incerteza as emissoes de GEE do GN fornecido a Portugal. Foi desenvolvido um modelo matematico, em linguagem de Programacao General Algebraic Modeling System (GAMS), que utiliza os resultados da ACV dos sistemas de energia e as suas implicacoes economicas para minimizar o CCV e IACV ao longo de um horizonte de planeamento definido pelo decisor. Foram derivadas fronteiras otimas de Pareto, representando as relacoes entre o tipo de IACV (CEP, GEE, acidificacao, eutrofizacao) e CCV decorrentes da satisfacao das necessidades energeticas do edificio. Para aumentar a robustez do modelo, dada a incerteza dos precos dos combustiveis (GN e eletricidade), foi desenvolvido um modelo de custos robusto para os sistemas de GD, que e menos afetado por perturbacoes relativas aos custos de combustivel. A aplicacao do modelo proposto foi testada num caso de estudo real, um edificio comercial localizado na cidade de Coimbra, em Portugal.

  17. Fully Ab-Initio Determination of the Thermoelectric Properties of Half-Heusler NiTiSn: Crucial Role of Interstitial Ni Defects.

    PubMed

    Berche, Alexandre; Jund, Philippe

    2018-05-23

    For thermoelectric applications, ab initio methods generally fail to predict the transport properties of the materials because of their inability to predict properly the carrier concentrations that control the electronic properties. In this work, a methodology to fill in this gap is applied on the NiTiSn half Heusler phase. For that, we show that the main defects act as donor of electrons and are responsible of the electronic properties of the material. Indeed, the presence of Ni i interstitial defects explains the experimental valence band spectrum and its associated band gap reported in the literature. Moreover, combining the DOS of the solid solutions with the determination of the energy of formation of charged defects, we show that Ni i defects are also responsible of the measured carrier concentration in experimentally supposed "pure" NiTiSn compounds. Subsequently the thermoelectric properties of NiTiSn can be calculated using a fully ab initio description and an overall correct agreement with experiments is obtained. This methodology can be extended to predict the result of extrinsic doping and thus to select the most efficient dopant for specific thermoelectric applications.

  18. Adsorption studies of volatile organic compounds on germanene nanotube emitted from banana fruit for quality assessment - A density functional application.

    PubMed

    Srimathi, U; Nagarajan, V; Chandiramouli, R

    2018-06-01

    We report the density functional application of adsorption behavior of volatile organic compounds (VOCs) emitted from the different ripening stages of banana fruit on germanene nanotube (GNT). Initially, the geometric structural stability of GNT is ascertained and the tunable electronic properties lead to the application of GNT as a base material in order to know the adsorption features of VOCs. We further explored the adsorption behavior of VOCs on to GNT through charge transfer, adsorption energy and band gap variation. The energy band structure and density of states (DOS) spectrum shows a noteworthy variation upon adsorption of different VOCs on to the GNT. Also, the electron density variation is noticed upon adsorption of VOCs emitted from the banana on to the GNT base material. Besides, the difference in the energy band gap of GNT upon emission of VOCs from banana leads to the use of GNT as a chemiresistor to assess fruit freshness with adsorption studies. Moreover, we suggest the use of GNT to discriminate the fruit freshness of banana through the adsorption process of VOCs on to GNT. Copyright © 2018 Elsevier Inc. All rights reserved.

  19. Fine resolution chronology based on initial Sr-87/Sr-86

    NASA Technical Reports Server (NTRS)

    Stewart, B. W.; Papanastassiou, D. A.; Capo, R. C.; Wasserburg, G. J.

    1993-01-01

    It has been recognized that small variations in initial Sr-87/Sr-86 (Sr(sub I)), can provide a fine scale relative chronology for the chemical fractionation of materials with low Rb/Sr from parent reservoirs with high Rb/Sr. Similarly, Sr(sub I), as determined for low Rb/Sr phases in meteorites, may permit a fine resolution chronology of the recrystallization or metamorphism of planetary materials. For the establishment of a primitive Sr-87/Sr-86 chronology, it is important to search for samples with extremely low Rb/Sr for which the measured Sr-87/Sr-86 is below BABI, in which case the primitive nature of the Sr can be directly established. Using the measured Rb/Sr to calculate an initial Sr-87/Sr-86 can introduce substantial uncertainty if the Rb-Sr are disturbed. We report Sr-87/Sr-86 in plagioclase from silicate pebbles from the Vaca Muerta mesosiderite on which we have reported Sm-147-Nd-143 and Ne-142 correlations. For the purpose of cross-calibration with our previous work we have performed extensive new measurements on Angra dos Reis and on anorthite from Moore County, which have very low Rb/Sr and primitive Sr-87/Sr-86.

  20. Observation of self-regulating response in Li xM yMn 2-yO 4 (M=Mn, Ni): A study using density functional theory

    NASA Astrophysics Data System (ADS)

    Ragavendran, K.; Sherwood, Daniel; Emmanuel, Bosco

    2009-02-01

    Density functional theory is used to understand the response of the transition metal-oxygen octahedra in Li xMn 2O 4 and Li xNi 0.5Mn 1.5O 4 to lithium intercalation and de-intercalation. Electronic structure computations on these compounds for x=0, 0.5 and 1 indicate that the 3d DOS of Mn is almost unaffected to variations in x. On the other hand, the oxygen 2p-DOS and to a lesser extent Ni 3d DOS are found to be sensitive to perturbation. The observations are explained on the grounds of self-regulating response, characteristic of systems having localized d states that communicate with a covalent manifold.

  1. Development of a Response Planner using the UCT Algorithm for Cyber Defense

    DTIC Science & Technology

    2013-03-01

    writer2l, guess passwd r2l, imap r2l, ipsweep probe, land dos, loadmodule u2r, multihop r2l, neptune dos, nmap probe, perl u2r, phf r2l, pod dos, portsweep...2646 10 pod 201 11 back 956 12 guess passwd 53 Item Type Count 13 ftp write 8 14 multihop 7 15 rootkit 10 16 buffer overflow 30 17 imap 11 18...pod 0 0 0 87 6 11 0 0 64 33 0 0 0 0 k = back 908 0 0 0 0 0 0 0 0 0 47 0 1 0 l = guess passwd 0 0 0 42 3 0 1 0 0 0 0 5 1 0 m = buffer overflow 0 0 17

  2. Estudo em microondas do aprisionamento e precipitação de elétrons em explosões solares

    NASA Astrophysics Data System (ADS)

    Rosal, A. C.; Costa, J. E. R.

    2003-08-01

    Uma explosão solar é uma variação rápida e intensa do brilho que ocorre nas chamadas regiões ativas da atmosfera, constituídas por um plasma magnetizado com intensa indução magnética. Os modelos de explosões solares atuais, discutidos na literatura, apresentam características de aprisionamento e precipitação de elétrons em ambientes magnéticos simplificados. Neste trabalho, nos propusemos a separar a emissão dos elétrons aprisionados da emissão dos elétrons em precipitação apenas a partir da emissão em microondas, melhorando portanto o controle sobre o conjunto de parâmetros inferidos. A emissão em microondas da população em precipitação é bastante fraca e portanto da nossa base de dados de 130 explosões observadas pelo Rádio Polarímetro de Nobeyama, em sete freqüências, apenas para 32 foi possível separar as duas componentes de emissão com uma boa razão sinal/ruído. A partir de estudos das escalas de tempo das emissões devidas à variação gradual da emissão no aprisionamento e da variação rápida da emissão dos elétrons em precipitação foi possível obter a separação utilizando um filtro temporal nas emissões resultantes. Em nossa análise destas explosões estudamos os espectros girossincrotrônicos da emissão gradual, a qual associamos provir do topo dos arcos magnéticos e da emissão de variação rápida associada aos elétrons em precipitação. Estes espectros foram calculados e dos quais inferimos que a indução magnética efetiva do topo e dos pés foi em média, Btopo = 236 G e Bpés = 577 G, inferidas das freqüências de pico dos espectros em ntopo = 11,8 GHz e npés = 14,6 GHz com leve anisotropia (pequeno alargamento espectral). O índice espectral da distribuição não-térmica de elétrons d, inferido do índice espectral de fótons da emissão em regime opticamente fino, foi de dtopo = 3,3 e dpés = 3,9. Estes parâmetros são típicos da maioria das análises realizadas em ambiente único de emissão e a relação dos índices espectrais, dpés > dtopo prioriza as interpretações com difusão em ângulo de passo devida a colisões Coulombianas. Nesta difusão o déficit de elétrons energéticos na precipitação seria uma conseqüência natural da dependência em e-3/2 das colisões elétron-próton (onde e é a energia dos elétrons).

  3. Percepção astronómica de um grupo de alunos do ensino médio de uma escola da rede estadual de São Paulo

    NASA Astrophysics Data System (ADS)

    de Oliveria, E. F.; Voelzke, M. R.

    2009-03-01

    Sendo a Astronomia uma das cièncias mais antigas da humanidade, e considerando sua importáncia histórica e cultural, é de extrema releváncia que tópicos relacionados a ela sejam tratados nas escolas. Embora os Parámetros Curriculares Nacionais do Ensino Médio (PCN-EM) e as Orientaçiacute;es Complementares aos Parámetros (PCN+) apontem a importáncia de uma abordagem significativa de conceitos relacionados à Astronomia nas aulas de Física, muitos estudantes terminam o Ensino Médio (EM) sem compreender a razão de certos acontecimentos de origem celeste, ainda que estes façam parte de seu cotidiano e sejam alvos da curiosidade natural dos jovens. Da observação dessa curiosidade em alunos de uma escola pública paulista, na cidade de Suzano, surgiu o interesse em investigar os conhecimentos básicos em Astronomia dos alunos do Ensino Médio desta escola, constituindo-se este como principal objetivo desta pesquisa. Para tanto foi elaborado um questionário de múltipla escolha aplicado inicialmente a 34 alunos do primeiro ano e, posteriormente, a mais 310, distribuídos entre as très séries do Ensino Médio dos períodos matutino e noturno. Dessa forma, observou-se que 73,9% dos estudantes identificaram o Sol como sendo uma estrela, 67,1% mostraram compreender a sucessão entre dia e noite e 52,3% relacionaram o Big Bang à origem do Universo. Em contrapartida, apenas 34,5% relacionaram as estaçíes do ano à inclinação do eixo de rotação da Terra, 21,3% indicaram a influència gravitacional simultánea da Lua e do Sol como responsável pelo fenòmeno das marés, 24,5% indicaram corretamente quais são os objetos celestes mais próximos da Terra, 36,1% identificaram ano-luz como uma medida de distáncia e 34,2% reconheceram as estrelas cadentes como meteoros, evidenciando-se assim o pequeno discernimento dos estudantes quanto aos fenòmenos e termos astronòmicos do cotidiano. Além disso, foram comparadas as respostas de alun! os de diferentes séries e períodos, observando-se, dentre ou tras coi sas, que os estudantes do terceiro ano apresentam um percentual de acertos semelhante ao dos alunos do primeiro, caracterizando que a abordagem de tópicos relacionados à astronomia no Ensino Médio não tem contribuído de forma significativa para uma maior compreensão dos fenòmenos e conceitos.

  4. Low effective mass and carrier concentration optimization for high performance p-type Mg2(1-x)Li2xSi0.3Sn0.7 solid solutions.

    PubMed

    Zhang, Qiang; Cheng, Long; Liu, Wei; Zheng, Yun; Su, Xianli; Chi, Hang; Liu, Huijun; Yan, Yonggao; Tang, Xinfeng; Uher, Ctirad

    2014-11-21

    Mg2Si1-xSnx solid solutions are promising thermoelectric materials for power generation applications in the 500-800 K range. Outstanding n-type forms of these solid solutions have been developed in the past few years with the thermoelectric figure of merit ZT as high as 1.4. Unfortunately, no comparable performance has been achieved so far with p-type forms of the structure. In this work, we use Li doping on Mg sites in an attempt to enhance and control the concentration of hole carriers. We show that Li as well as Ga is a far more effective p-type dopant in comparison to Na or K. With the increasing content of Li, the electrical conductivity rises rapidly on account of a significantly enhanced density of holes. While the Seebeck coefficient decreases concomitantly, the power factor retains robust values supported by a rather high mobility of holes. Theoretical calculations indicate that Mg2Si0.3Sn0.7 intrinsically possesses the almost convergent double valence band structure (the light and heavy band), and Li doping retains a low density of states (DOS) on the top of the valence band, contrary to the Ga doping at the sites of Si/Sn. Low temperature specific heat capacity studies attest to a low DOS effective mass in Li-doped samples and consequently their larger hole mobility. The overall effect is a large power factor of Li-doped solid solutions. Although the thermal conductivity increases as more Li is incorporated in the structure, the enhanced carrier density effectively shifts the onset of intrinsic excitations (bipolar effect) to higher temperatures, and the beneficial role of phonon Umklapp processes as the primary limiting factor to the lattice thermal conductivity is thus extended. The final outcome is the figure of merit ZT ∼ 0.5 at 750 K for x = 0.07. This represents a 30% improvement in the figure of merit of p-type Mg2Si1-xSnx solid solutions over the literature values. Hence, designing low DOS near Fermi level EF for given carrier pockets can serve as an effective approach to optimize the PF and thus ZT value.

  5. ACARA - AVAILABILITY, COST AND RESOURCE ALLOCATION

    NASA Technical Reports Server (NTRS)

    Viterna, L. A.

    1994-01-01

    ACARA is a program for analyzing availability, lifecycle cost, and resource scheduling. It uses a statistical Monte Carlo method to simulate a system's capacity states as well as component failure and repair. Component failures are modelled using a combination of exponential and Weibull probability distributions. ACARA schedules component replacement to achieve optimum system performance. The scheduling will comply with any constraints on component production, resupply vehicle capacity, on-site spares, or crew manpower and equipment. ACARA is capable of many types of analyses and trade studies because of its integrated approach. It characterizes the system performance in terms of both state availability and equivalent availability (a weighted average of state availability). It can determine the probability of exceeding a capacity state to assess reliability and loss of load probability. It can also evaluate the effect of resource constraints on system availability and lifecycle cost. ACARA interprets the results of a simulation and displays tables and charts for: (1) performance, i.e., availability and reliability of capacity states, (2) frequency of failure and repair, (3) lifecycle cost, including hardware, transportation, and maintenance, and (4) usage of available resources, including mass, volume, and maintenance man-hours. ACARA incorporates a user-friendly, menu-driven interface with full screen data entry. It provides a file management system to store and retrieve input and output datasets for system simulation scenarios. ACARA is written in APL2 using the APL2 interpreter for IBM PC compatible systems running MS-DOS. Hardware requirements for the APL2 system include 640K of RAM, 2Mb of extended memory, and an 80386 or 80486 processor with an 80x87 math co-processor. A dot matrix printer is required if the user wishes to print a graph from a results table. A sample MS-DOS executable is provided on the distribution medium. The executable contains licensed material from the APL2 for the IBM PC product which is program property of IBM; Copyright IBM Corporation 1988 - All rights reserved. It is distributed with IBM's permission. The standard distribution medium for this program is a set of three 5.25 inch 360K MS-DOS format diskettes. The contents of the diskettes are compressed using the PKWARE archiving tools. The utility to unarchive the files, PKUNZIP.EXE, is included. ACARA was developed in 1992.

  6. METCAN-PC - METAL MATRIX COMPOSITE ANALYZER

    NASA Technical Reports Server (NTRS)

    Murthy, P. L.

    1994-01-01

    High temperature metal matrix composites offer great potential for use in advanced aerospace structural applications. The realization of this potential however, requires concurrent developments in (1) a technology base for fabricating high temperature metal matrix composite structural components, (2) experimental techniques for measuring their thermal and mechanical characteristics, and (3) computational methods to predict their behavior. METCAN (METal matrix Composite ANalyzer) is a computer program developed to predict this behavior. METCAN can be used to computationally simulate the non-linear behavior of high temperature metal matrix composites (HT-MMC), thus allowing the potential payoff for the specific application to be assessed. It provides a comprehensive analysis of composite thermal and mechanical performance. METCAN treats material nonlinearity at the constituent (fiber, matrix, and interphase) level, where the behavior of each constituent is modeled accounting for time-temperature-stress dependence. The composite properties are synthesized from the constituent instantaneous properties by making use of composite micromechanics and macromechanics. Factors which affect the behavior of the composite properties include the fabrication process variables, the fiber and matrix properties, the bonding between the fiber and matrix and/or the properties of the interphase between the fiber and matrix. The METCAN simulation is performed as point-wise analysis and produces composite properties which are readily incorporated into a finite element code to perform a global structural analysis. After the global structural analysis is performed, METCAN decomposes the composite properties back into the localized response at the various levels of the simulation. At this point the constituent properties are updated and the next iteration in the analysis is initiated. This cyclic procedure is referred to as the integrated approach to metal matrix composite analysis. METCAN-PC is written in FORTRAN 77 for IBM PC series and compatible computers running MS-DOS. An 80286 machine with an 80287 math co-processor is required for execution. The executable requires at least 640K of RAM and DOS 3.1 or higher. The package includes sample executables which were compiled under Microsoft FORTRAN v. 5.1. The standard distribution medium for this program is one 5.25 inch 360K MS-DOS format diskette. The contents of the diskette are compressed using the PKWARE archiving tools. The utility to unarchive the files, PKUNZIP.EXE, is included. METCAN-PC was developed in 1992.

  7. Costs of topical treatment of pressure ulcer patients.

    PubMed

    Andrade, Cynthia Carolina Duarte; Almeida, Cláudia Fernanda Dos Santos Calixto de; Pereira, Walkíria Euzébio; Alemão, Márcia Mascarenhas; Brandão, Cristina Mariano Ruas; Borges, Eline Lima

    2016-04-01

    To evaluate the costs of a topical treatment of pressure ulcer (PU) patients in a hospital unit for treatment of chronic patients in 2014. This is an activity-based costing study. This method encompasses the identification, measurement and pricing of physical and human resources consumed for dressings. Procedure costs varied between BRL 16.41 and BRL 260.18. For PUs of the same category, of near areas and with the same type of barrier/adjuvant, the cost varied between 3.5% and 614.6%. For most dressings, the cost increased proportionally to the increase of the area and to the development of PU category. The primary barrier accounted for a high percentage of costs among all items required to the application of dressings (human and material resources). Dressings applied in sacral PUs had longer application times. This study allowed us to understand the costs involved in the treatment of PUs, and it may support decision-makers and other cost-effectiveness studies. Realizar uma avaliação do custo do tratamento tópico de pacientes com úlceras por pressão (UP), em uma unidade hospitalar de atendimento a pacientes crônicos no ano de 2014. Trata-se de um estudo de custos baseado no Sistema de custeio Baseado em Atividades. Este método contempla a identificação, mensuração e precificação dos recursos físicos e humanos consumidos para a realização de curativos. Os custos dos procedimentos variaram de R$16,41 a R$260,18. Para UP de mesma categoria, de áreas aproximadas e mesmo tipo de cobertura/adjuvante, a variação entre os custos foi de 3,5% a 614,6%. Para a maioria dos curativos, o custo aumentou proporcionalmente ao aumento da área e à progressão da categoria das UP. A cobertura primária representou elevado percentual nos custos entre todos os itens necessários para realizar os curativos (recursos humanos e materiais). Os curativos realizados nas UP sacrais foram os que apresentaram maiores tempos para execução. Este estudo permitiu conhecer os custos envolvidos no tratamento das UP e pode fornecer subsídios para os tomadores de decisão, assim como para a realização de estudos de custo-efetividade.

  8. Operation Inherent Resolve

    DTIC Science & Technology

    2015-04-01

    suggestions for reducing this burden, to Washington Headquarters Services , Directorate for Information Operations and Reports, 1215 Jefferson Davis Highway... Service Auditors General to coordinate their oversight and avoid duplication of effort. Section 8L provides a new mandate for the three Lead IG...SUMMARY 7 • Medical Support Service in Iraq (DoS OIG). DoS OIG issued a manage- ment assistance report on concerns with oversight of medical support

  9. Sobre a largura da última superfície de espalhamento

    NASA Astrophysics Data System (ADS)

    Nobre, M. A. S.; Pires, N.; Lima, J. A. S.

    2003-08-01

    De acordo com o modelo do "Big-Bang", no universo primordial a matéria estava em equilíbrio térmico com a radiação. Com a expansão a temperatura da radiação cai. Quando a temperatura chega em torno dos 4.000K, os espalhamentos diminuem, começando a recombinação dos prótons e elétrons em Hidrogênio neutro (era conhecida como da recombinação). Ao final da recombinação, os fótons se propagam livremente sofrendo, em princípio, somente os efeitos do "redshift" cosmológico. Esses fótons nos alcançam hoje como a radiação cósmica de fundo (RCF), e parecem vir de uma superfície esférica ao nosso redor, tal que o raio dela é a distância que ele viajou desde seu último espalhamento na época da recombinação. Naturalmente, esse processo não ocorreu abruptamente, implicando na existência de uma largura no espaço dos "redshifts" que deve depender do modelo cosmológico específico e dos processos físicos considerados. Neste trabalho analisamos os efeitos de diferentes modelos - a saber, aqueles com decaimento do vácuo L(t), criação de matéria, quintessência e gás de Chaplygin - sobre a última superfície de espalhamento da RCF, em particular sua largura e a função visibilidade, que determina a probabilidade de um fóton ter tido seu último espalhamento num "redshift" z. No caso particular dos modelos com decaimento do vácuo, existe uma forte dependência da função visibilidade com L(t). Tais efeitos poderão ser testados através da análise dos resultados de experimentos mais precisos que estão atualmente em andamento, como por exemplo, o WMAP.

  10. Correspondence Between NANDA International Nursing Diagnoses and Outcomes as Proposed by the Nursing Outcomes Classification.

    PubMed

    de Carvalho, Emilia Campos; Eduardo, Aline Helena Appoloni; Romanzini, Adilson; Simão, Talita Prado; Zamarioli, Cristina Mara; Garbuio, Danielle Cristina; Herdman, Tracy Heather

    2018-01-01

    The accurate identification of the nursing diagnoses and the corresponding measurement of their indicators will depend on the elements in the standardized language systems. To analyze the correspondence between elements of four NANDA-I nursing diagnoses and outcomes suggested by the nursing outcomes classification (NOC) for the resolution of these diagnoses. A methodological study consisting of cross-mapping was performed in the first stage between definitions, defining characteristics (DCs), and related factors (RFs) of impaired oral mucous membrane, impaired tissue integrity, spiritual distress, and delayed surgical recovery and outcome definitions and indicators to measure results of diagnoses resolution and an analysis of its relevance by experts in the second stage. It found partial correspondence between outcome indicators, DCs, RFs, and definitions. The data evidence the relevance of this review for a reliable application of these taxonomies and demonstrated partial correspondence between concepts analyzed. A identificação precisa dos diagnósticos de enfermagem e a medida correspondente dos seus indicadores dependerá dos elementos nos sistemas de linguagem padronizados. Foi analisar a correspondência entre os elementos de quatro NANDA-I diagnósticos de enfermagem e os resultados sugeridos pelo NOC para a resolução destes diagnósticos. MÉTODO: um estudo metodológico que consiste em cross-mapping foi realizado em uma primeira fase entre as definições, características definidoras e fatores relacionados de Mucosa oral prejudicada, Integridade tissular prejudicada, Sofrimento espiritual e Recuperação cirúrgica retardada e as definições dos resultados indicados para a resolução destes diagnósticos; na segunda fase, foi realizada uma análise desta concordância por especialistas. RESULTADOS: correspondência parcial entre as definições dos diagnósticos e dos resultados, características definidoras e fatores relacionados. CONCLUSÃO: Os resultados evidenciam a relevância dessa avaliação para uma aplicação confiável destas taxonomias e demonstrou a correspondência parcial entre os conceitos analisados. © 2016 NANDA International, Inc.

  11. Illuminating the star clusters and satellite galaxies with multi-scale baryonic simulations

    NASA Astrophysics Data System (ADS)

    Maji, Moupiya; Zhu, Qirong; Li, Yuexing; Marinacci, Federico; Charlton, Jane; Hernquist, Lars; Knebe, Alexander

    2018-01-01

    Over the past decade, advances in computational architecture have made it possible for the first time to investigate some of the fundamental questions around the formation, evolution and assembly of the building blocks of the universe; star clusters and galaxies. In this talk, I will focus on two major questions: What is the origin of the observed universal lognormal mass function in globular clusters? What is the statistical distribution of the properties of satellite planes in a large sample of satellite systems?Observations of globular clusters show that they have universal lognormal mass functions with a characteristic peak at 2X105 MSun, although the origin of this peaked distribution is unclear. We investigate the formation of star clusters in interacting galaxies using baryonic simulations and found that massive clusters preferentially form in extremely high pressure gas clouds which reside in highly shocked regions produced by galaxy interactions. These massive clusters have quasi-lognormal initial mass functions with a peak around ~106MSun which may survive dynamical evolution and slowly evolve into the universal lognormal profiles observed today.The classical Milky Way (MW) satellites are observed to be distributed in a highly-flattened plane, called Disk of Satellites (DoS). However the significance, coherence and origin of DoS is highly debated. To understand this, we first analyze all MW satellites and find that a small sample size can artificially produce a highly anisotropic spatial distribution and a strong clustering of their angular momentum. Comparing a baryonic simulation of a MW-sized galaxy with its N-body counterpart we find that an anisotropic DoS can originate from baryonic processes. Furthermore, we explore the statistical distribution of DoS properties by analyzing 2591 satellite systems in the cosmological hydrodynamic simulation Illustris. We find that the DoS becomes more isotropic with increasing sample sizes and most (~90%) satellite systems have no clear coherent rotation. Their overall evolution indicate that the DoS may be part of large scale filamentary structure. Our results show that baryonic processes may be the key to solve many long standing theoretical problems.

  12. Alterações Induzidas Pelo Exercício no Número, Função e Morfologia de Monócitos de Ratos

    PubMed Central

    GUERESCHI, MARCIA G.; PRESTES, JONATO; DONATTO, FELIPE F.; DIAS, RODRIGO; FROLLINI, ANELENA B.; FERREIRA, CLÍLTON KO.; CAVAGLIERI, CLAUDIA R.; PALANCH, ADRIANNE C.

    2008-01-01

    O propósito desse estudo foi verificar as alterações histofisiológicas em monócitos e macrófagos induzidas por curtos períodos de exercícios. Ratos Wistar (idade = 2 meses, peso corporal = 200g) foram divididos em sete grupos (n=6 cada): controle sedentário (C), grupos exercitados (natação) na intensidade leve por 5 (5L), 10 (10L) e 15 minutos (15L), e grupos exercitados em intensidade moderada por 5 (5M), 10 (10M) e 15 minutes (15M). Na intensidade moderada os animais carregaram uma carga de 5% do peso corporal dos mesmos em seus respectivos dorsos. Os monócitos sangüíneos foram avaliados quanto à quantidade e morfologia e os macrófagos peritoneais foram analisados quanto à quantidade e atividade fagocitária. Os dados foram analisados usando ANOVA e Tukey’s post hoc test (p ≤ 0,05). Os grupos de intensidade leve e 5M apresentaram aumento nos níveis dos monócitos quando comparados com o controle. Foi observado aumento na área celular dos monócitos para os grupos 5L, 10L, 5M e 10M; a área nuclear aumentou para os grupos 10L, 5M e 10M em comparação com o controle. Houve aumento nos macrófagos peritoneais para os grupos 15L, 10M, 15M e diminuição no grupo 5M. A capacidade fagocitária dos macrófagos aumentou nos grupos de intensidade leve e para o grupo 10M. O exercício realizado por curtos períodos modulou o número e função dos macrófagos, assim como o número e morfologia dos monócitos, sendo tais alterações dependentes da intensidade. A soma das respostas agudas observadas nesse estudo pode exercer um efeito protetor contra doenças, podendo ser utilizada para a melhora da saúde e qualidade de vida.

  13. Role of the treating surgeon in the consent process for elective refractive surgery

    PubMed Central

    Schallhorn, Steven C; Hannan, Stephen J; Teenan, David; Schallhorn, Julie M

    2016-01-01

    Purpose To compare patient’s perception of consent quality, clinical and quality-of-life outcomes after laser vision correction (LVC) and refractive lens exchange (RLE) between patients who met their treating surgeon prior to the day of surgery (PDOS) or on the day of surgery (DOS). Design Retrospective, comparative case series. Setting Optical Express, Glasgow, UK. Methods Patients treated between October 2015 and June 2016 (3972 LVC and 979 RLE patients) who attended 1-day and 1-month postoperative aftercare and answered a questionnaire were included in this study. All patients had a thorough preoperative discussion with an optometrist, watched a video consent, and were provided with written information. Patients then had a verbal discussion with their treating surgeon either PDOS or on the DOS, according to patient preference. Preoperative and 1-month postoperative visual acuity, refraction, preoperative, 1-day and 1-month postoperative questionnaire were compared between DOS and PDOS patients. Multivariate regression model was developed to find factors associated with patient’s perception of consent quality. Results Preoperatively, 8.0% of LVC and 17.1% of RLE patients elected to meet their surgeon ahead of the surgery day. In the LVC group, 97.5% of DOS and 97.2% of PDOS patients indicated they were properly consented for surgery (P=0.77). In the RLE group, 97.0% of DOS and 97.0% of PDOS patients stated their consent process for surgery was adequate (P=0.98). There was no statistically significant difference between DOS and PDOS patients in most of the postoperative clinical or questionnaire outcomes. Factors predictive of patient’s satisfaction with consent quality were postoperative satisfaction with vision (46.7% of explained variance), difficulties with night driving, close-up vision or outdoor/sports activities (25.4%), visual phenomena (12.2%), dry eyes (7.5%), and patient’s satisfaction with surgeon’s care (8.2%). Conclusion Perception of quality of consent was comparable between patients that elected to meet the surgeon PDOS, and those who did not. PMID:27932862

  14. Análise sobre o Conhecimento de um Grupo de Alunos do Ensino Médio da Rede Estadual de São Paulo sobre Termos e Fenômenos Astronômicos do Cotidiano

    NASA Astrophysics Data System (ADS)

    de Oliveira, E. F.; Voelzke, M. R.; Amaral, L. H.

    2007-08-01

    Embora os Parâmetros Curriculares Nacionais do Ensino Médio (PCN-EM) e as orientações complementares a esses Parâmetros (PCN+) apontem a importância de uma abordagem significativa de conceitos relacionados à astronomia nas aulas de Física, muitos estudantes terminam o Ensino Médio (EM) sem compreender a razão de certos acontecimentos de origem celeste, ainda que estes façam parte de seu cotidiano. Este trabalho tem por objetivo analisar os conhecimentos básicos em astronomia dos alunos de EM da escola estadual Batista Renzi, bem como investigar os meios através dos quais estes conhecimentos foram adquiridos. Para tanto foi elaborado um questionário de múltipla escolha aplicado a 310 alunos distribuídos entre as três séries do EM dos períodos matutino e noturno. Dessa forma, observou-se que apenas 34,5% relacionaram as estações do ano à inclinação do eixo de rotação da Terra, 21,3% indicaram a influência gravitacional da Lua e do Sol como responsáveis pelo fenômeno das marés, 24,5% indicaram corretamente quais são os objetos celestes mais próximos da Terra, 36,1% identificaram ano-luz como uma medida de distância e 34,2% reconheceram uma estrela cadente como meteoro. Em contrapartida, 67,1% compreendiam a sucessão entre dia e noite, 73,9% identificaram o Sol como estrela e 52,3% relacionaram o Big Bang à origem do Universo. Além disso, foram comparadas as respostas de alunos de diferentes séries e períodos, observando-se, dentre outras coisas, que os estudantes do terceiro ano apresentam um percentual de acertos semelhante ao dos alunos do primeiro, caracterizando que a abordagem de tópicos relacionados à astronomia no EM não tem contribuído para uma maior compreensão dos fenômenos e conceitos.

  15. The impact of osteopathic physicians' participation in ACGME-accredited postdoctoral programs, 1985-2006.

    PubMed

    Cummings, Mark; Sefcik, Donald J

    2009-06-01

    Between 1985 and 2006, the number of osteopathic physicians (DOs) training in Accreditation Council for Graduate Medical Education (ACGME) postdoctoral (i.e., residency and fellowship) programs increased by 5,352 (419%). In 2006, more than two of every three DOs (6,629 of 9,618) in postdoctoral training were in an ACGME program. The integration of osteopathic physicians into these programs was facilitated by several factors. The most important of these was a noted growth in the number and types of ACGME programs and a consistent number of U.S. MD graduates (USMDs) from schools accredited by the Liaison Committee on Medical Education (LCME). From 1985 to 2006, the number of all physicians in ACGME programs, both DO and MD, grew by 30,365 (41%). DOs were most often selected for specialties less populated by USMDs, chiefly family and internal medicine and pediatrics.Growth patterns in LCME medical schools project an increase in the national class size to accommodate 3,400 more students by 2012, a 21% increase. The development of new colleges of osteopathic medicine (COMs) and expansion in existing ones is expected to generate 5,227 first-year students in 2012, an increase of 1,380 students (36%) over 2006 numbers. The overwhelming majority of these anticipated new COM graduates cannot be accommodated in American Osteopathic Association postdoctoral programs because of limited capacity. As these additional LCME graduates move into their postdoctoral training, educational opportunities for DOs are expected to decline and competition is expected to become stiffer. The window of opportunity for DOs in ACGME programs that opened in the last two decades will gradually start to close.

  16. WT - WIND TUNNEL PERFORMANCE ANALYSIS

    NASA Technical Reports Server (NTRS)

    Viterna, L. A.

    1994-01-01

    WT was developed to calculate fan rotor power requirements and output thrust for a closed loop wind tunnel. The program uses blade element theory to calculate aerodynamic forces along the blade using airfoil lift and drag characteristics at an appropriate blade aspect ratio. A tip loss model is also used which reduces the lift coefficient to zero for the outer three percent of the blade radius. The application of momentum theory is not used to determine the axial velocity at the rotor plane. Unlike a propeller, the wind tunnel rotor is prevented from producing an increase in velocity in the slipstream. Instead, velocities at the rotor plane are used as input. Other input for WT includes rotational speed, rotor geometry, and airfoil characteristics. Inputs for rotor blade geometry include blade radius, hub radius, number of blades, and pitch angle. Airfoil aerodynamic inputs include angle at zero lift coefficient, positive stall angle, drag coefficient at zero lift coefficient, and drag coefficient at stall. WT is written in APL2 using IBM's APL2 interpreter for IBM PC series and compatible computers running MS-DOS. WT requires a CGA or better color monitor for display. It also requires 640K of RAM and MS-DOS v3.1 or later for execution. Both an MS-DOS executable and the source code are provided on the distribution medium. The standard distribution medium for WT is a 5.25 inch 360K MS-DOS format diskette in PKZIP format. The utility to unarchive the files, PKUNZIP, is also included. WT was developed in 1991. APL2 and IBM PC are registered trademarks of International Business Machines Corporation. MS-DOS is a registered trademark of Microsoft Corporation. PKUNZIP is a registered trademark of PKWare, Inc.

  17. Ten-year stability and variability, drinking patterns, and impairment in community youth with diagnostic orphan status of alcohol dependence.

    PubMed

    Grabitz, Maike; Behrendt, Silke; Klotsche, Jens; Buehringer, Gerhard; Lieb, Roselind; Wittchen, Hans-Ullrich

    2012-04-01

    Some adolescents and young adults who do not fulfill criteria for DSM-IV alcohol abuse (AA) report symptoms of DSM-IV alcohol dependence (AD) below the diagnostic threshold (diagnostic orphans, DOs; 1 or 2 symptoms). Contemporarily, little is known on the long-term stability, risk of progression to AD, impairment, and drinking patterns possibly associated with this status in the first decades of life. (1) To identify prevalence rates of the DO status from adolescence to early adulthood. To investigate (2) stability and variability of the DO status over time and (3) associations between DO status, drinking patterns and impairment in comparison to subjects with AA, with AD, or without any symptoms. N=2039 community subjects (aged 14-24 years at baseline) were assessed at baseline and at about four and ten years after baseline. DSM-IV AUD diagnoses were obtained with the DIA-X/M-CIDI. About 11-12% of the sample was classified as DOs at all waves. Over a period of ten years, 18% of DOs were stable in their diagnosis and additional 10% progressed to AD. DOs were comparable to subjects with AA in drinking patterns, impairment and stability of diagnostic status. DOs progressed to AD significantly more often than AA. AD was associated with highest levels in all outcomes of interest. The DO status in adolescence and early adulthood is associated with considerable stability, risk of progression and problematic alcohol intake. In consequence, it can be meaningful for the timely identification of early stages of clinically relevant alcohol problems. For subjects with DO status early specific interventions are required. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. On Ensino de Astronomia: Desafios para Implantação

    NASA Astrophysics Data System (ADS)

    Faria, R. Z.; Voelzke, M. R.

    2008-09-01

    Em 2002 o ensino de Astronomia foi proposto como um dos temas estruturadores pelos Parâmetros Curriculares Nacionais e sugerido como facilitador para que o aluno compreendesse a Física como construção humana e parte do seu mundo vivencial, mas raramente seus conceitos foram ensinados. A presente pesquisa discute dois aspectos relacionados à abordagem de Astronomia. O primeiro aspecto é se ela está sendo abordada pelos professores do Ensino Médio e o segundo, aborda a maneira como ela está sendo ensinada. Optou-se pela aplicação de um questionário a partir do 2° semestre de 2006 e durante o ano de 2007 com professores que ministram a disciplina de Física, os quais trabalham em escolas estaduais em Rio Grande da Serra, Ribeirão Pires e Mauá no estado São Paulo. Dos 66,2% dos professores que responderam ao questionário nos municípios de Rio Grande da Serra, Ribeirão Pires e Mauá, 57,4% não aplicaram nenhum tópico de astronomia, 70,2% não utilizaram laboratório, 89,4% não utilizaram qualquer tipo de programa computacional, 83,0% nunca fizeram visitas com alunos a museus e planetários e 38,3% não indicaram qualquer tipo de livro ou revista referente à astronomia aos seus alunos. Mesmo considerando a Astronomia um conteúdo potencialmente significativo, esta não fez parte dos planejamentos escolares. Portanto são necessárias propostas que visem estratégias para a educação continuada dos professores como, por exemplo, cursos específicos sobre o ensino em Astronomia.

  19. Mouse cumulus-denuded oocytes restore developmental capacity completely when matured with optimal supplementation of cysteamine, cystine, and cumulus cells.

    PubMed

    Zhou, Ping; Wu, Yan-Guang; Wei, De-Li; Li, Qing; Wang, Gang; Zhang, Jie; Luo, Ming-Jiu; Tan, Jing-He

    2010-04-01

    Our objectives were to study how cysteamine, cystine, and cumulus cells (CCs), as well as oocytes interact to increase oocyte intracellular glutathione (GSH) and thereby to establish an efficient in vitro maturation system for cumulus-denuded oocytes (DOs). Using M16 that contained no thiol as maturation medium, we showed that when supplemented alone, neither cystine nor cysteamine promoted GSH synthesis of mouse DOs, but they did when used together. Although goat CCs required either cysteamine or cystine to promote GSH synthesis, mouse CCs required both. In the presence of cystine, goat CCs produced cysteine but mouse CCs did not. Cysteamine reduced cystine to cysteine in cell-free M16. When TCM-199 that contained 83 microM cystine was used as maturation medium, supplementation with cysteamine alone had no effect, but supplementation with 100 microM cysteamine and 200 microM cystine increased blastulation of DOs matured with CC coculture to a level as high as achieved in cumulus-surrounded oocytes (COCs). Similar numbers of young were produced after two-cell embryos from mouse COCs or CC-cocultured DOs matured with optimal thiol supplementation were transferred to pseudopregnant recipients. It is concluded that 1) mouse CCs can use neither cysteamine nor cystine to promote GSH synthesis, but goat CCs can use either one; 2) goat CCs promote mouse oocyte GSH synthesis by reducing cystine to cysteine, but how they use cysteamine requires further investigation; and 3) mouse DOs can use neither cystine nor cysteamine for GSH synthesis, but they restore developmental capacity completely when matured in the presence of optimum supplementation of cysteamine, cystine, and CCs.

  20. Trap density of states in small-molecule organic semiconductors: A quantitative comparison of thin-film transistors with single crystals

    NASA Astrophysics Data System (ADS)

    Kalb, Wolfgang L.; Haas, Simon; Krellner, Cornelius; Mathis, Thomas; Batlogg, Bertram

    2010-04-01

    We show that it is possible to reach one of the ultimate goals of organic electronics: producing organic field-effect transistors with trap densities as low as in the bulk of single crystals. We studied the spectral density of localized states in the band gap [trap density of states (trap DOS)] of small-molecule organic semiconductors as derived from electrical characteristics of organic field-effect transistors or from space-charge-limited current measurements. This was done by comparing data from a large number of samples including thin-film transistors (TFT’s), single crystal field-effect transistors (SC-FET’s) and bulk samples. The compilation of all data strongly suggests that structural defects associated with grain boundaries are the main cause of “fast” hole traps in TFT’s made with vacuum-evaporated pentacene. For high-performance transistors made with small-molecule semiconductors such as rubrene it is essential to reduce the dipolar disorder caused by water adsorbed on the gate dielectric surface. In samples with very low trap densities, we sometimes observe a steep increase in the trap DOS very close (<0.15eV) to the mobility edge with a characteristic slope of 10-20 meV. It is discussed to what degree band broadening due to the thermal fluctuation of the intermolecular transfer integral is reflected in this steep increase in the trap DOS. Moreover, we show that the trap DOS in TFT’s with small-molecule semiconductors is very similar to the trap DOS in hydrogenated amorphous silicon even though polycrystalline films of small-molecules with van der Waals-type interaction on the one hand are compared with covalently bound amorphous silicon on the other hand.

  1. DEVELOPMENT OF METRICS FOR TECHNICAL PRODUCTION: QUALIS BOOKS AND BOOK CHAPTERS.

    PubMed

    Ribas-Filho, Jurandir Marcondes; Malafaia, Osvaldo; Czeczko, Nicolau Gregori; Ribas, Carmen A P Marcondes; Nassif, Paulo Afonso Nunes

    2015-01-01

    To propose metrics to qualify the publication in books and chapters, and from there, establish guidance for the evaluation of the Medicine III programs. Analysis of some of the 2013 area documents focusing this issue. Were analyzed the following areas: Computer Science; Biotechnology; Biological Sciences I; Public Health; Medicine I. Except for the Medicine I, which has not adopted the metric for books and chapters, all other programs established metrics within the intellectual production, although with unequal percentages. It´s desirable to include metrics for books and book chapters in the intellectual production of post-graduate programs in Area Document with percentage-value of 5% in publications of Medicine III programs. Propor a métrica para qualificar a produção veiculada através de livros e capítulos e, a partir daí, estabelecer orientação para a avaliação dos programas de pós-graduação da Medicina III. Análise dos documentos de área de 2013 dos programas de pós-graduação senso estrito das áreas: Ciência da Computação; Biotecnologia; Ciências Biológicas I; Saúde Coletiva; Medicina I. Excetuando-se o programa da Medicina I, que não adotou a métrica para classificação de livros e capítulos, todos os demais estabeleceram-na dentro da sua produção intelectual, embora com percentuais desiguais. É desejável inserir a métrica de livros e capitulos de livros na produção intelectual do Documento de Área dos programas, ortorgando a ela percentual de 5% das publicações qualificadas dos programas da Medicina III.

  2. Using satellite images to monitor glacial-lake outburst floods: Lago Cachet Dos drainage, Chile

    USGS Publications Warehouse

    Friesen, Beverly A.; Cole, Christopher J.; Nimick, David A.; Wilson, Earl M.; Fahey, Mark J.; McGrath, Daniel J.; Leidich, Jonathan

    2015-01-01

    During 2008–2013, 14 GLOFs were released from Lago Cachet Dos and created environmental and safety concerns for downstream residents and to infrastructure. If GLOFs and the consequent headward erosion continue, the moraine that creates Lago Cachet Uno could be destabilized and breached, and the two lakes could merge. If the two lakes become connected, the volume of future GLOFs likely would be greater and thus cause longer and (or) more extensive flooding downstream. Additional GLOFs from Lago Cachet Dos are expected in the future, and continued environmental monitoring could provide an early warning system as well as scientific information that could increase our understanding of GLOFs and their consequences. GLOFs occur in glaciated areas around the world and remote sensing technologies can allow researchers to better understand—and potentially predict—future GLOF events.

  3. Mechanical behavior, electronic and phonon properties of ZrB12 under pressure

    NASA Astrophysics Data System (ADS)

    Li, Xiao-Hong; Yong, Yong-Liang; Cui, Hong-Ling; Zhang, Rui-Zhou

    2018-06-01

    The mechanical, phonon and electronic properties of ZrB12 under pressure are investigated by first-principles calculations. The research shows that ZrB12 is mechanically and dynamically stable up to 100 GPa. The elastic constants, bulk modulus B, shear modulus G, hardness Hv, B/G ratio, Debye temperature under different pressures are systematically investigated. The calculation of electronic properties shows that ZrB12 has metallic character. The Zr-d states dominate the DOS at the Fermi level, and the total DOS and PDOS change slightly with the increasing pressure. DOS (Ef) first decreases, then increases with the increasing pressure. At 50 GPa, ZrB12 has less electron carriers. The analysis of electron localization function shows that the strong B-B and Zr-B covalent bonds may be responsible for the high hardness and stability.

  4. Buracos negros primordiais e astrofísica observacional

    NASA Astrophysics Data System (ADS)

    Custódio, P. S.; Horvath, J. E.

    2003-02-01

    A história da física contemporânea é pródiga em grandes descobertas (a Relatividade e a Mecânica Quântica entre as mais importantes) até meados dos anos '30. O peso destes desenvolvimentos é tão grande que outros feitos de grande porte (por exemplo, a teoria da nucleossíntese nas estrelas) são geralmente considerados como "filhotes" dos primeiros, ao menos na imaginação popular. Porém, algumas exceções à regra não-escrita são dignas de menção. Entre estas últimas está a descoberta por S.W.Hawking e colaboradores das propriedades de emissão dos buracos negros, trabalho que iniciou uma disciplina com vida própria denominada Termodinâmica de Buracos Negros.

  5. Fabrication of a novel carbon nanotube & graphene based device for gas detection

    NASA Astrophysics Data System (ADS)

    Khosravi, Yusef; Abdi, Yaser; Arzi, Ezatollah

    2018-06-01

    We present a novel, simple method for gas detection using a nano-device fabricated on a silicon substrate. The proposed method is based on changing the density of state (DOS) of a graphene sheet during the gas absorption. Fabrication of the carbon nanotube (CNT) and graphene based device for gas detection includes silicon micro machining and the growth of vertically aligned CNTs. Field emission between the as-grown CNTs and the graphene sheet which is placed on top of the CNTs is measured at a liquid nitrogen temperature to obtain the DOS of the structure in different gas environments. The measured local DOS of the structure using the fabricated device showed that each gas had its own signatory spectrum. We believe that this method will open up a new and simple way of fabricating a portable gas spectroscope.

  6. An Ounce of Prevention Beats a Pound of Cure: Resourcing the State Department to Defend the Nation

    DTIC Science & Technology

    2010-04-01

    17 The DOS lacks the resources to lead USG efforts .....................................................25 Summary...failing states 5) The DOS lacks the resources to lead USG efforts After compelling the reader to accept these five arguments, a disparity in US foreign...world‟s most powerful nation. The nation-states in which these terrorists operate lack the ability to monitor or disrupt the operations of these

  7. Preparing to Win in a Complex World: Institutionalizing Interagency Cooperation at the Tactical Level

    DTIC Science & Technology

    2016-06-10

    inefficiencies have even escalated to cases where soldiers in the brigades experienced challenges and delays in obtaining official passports . Despite...USARAF and RAF BCTs supporting DoS coordinated and approved security cooperation activities, DoS passport procedures have denied many soldiers from...draw from, in order to support sometimes late notice security cooperation activities. As a result, brigades often 84 put in blanket official passport

  8. 8 CFR 286.9 - Fee for processing applications and issuing documentation at land border Ports-of-Entry.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    .../Departure Record, for admission at a land border Port-of-Entry must remit the required fee for issuance of... Card, issued by the DOS, or a passport and combined B-1/B-2 visa and non-biometric BCC (or similar stamp in a passport) issued by the DOS, who is required to be issued Form I-94, Arrival/Departure Record...

  9. 8 CFR 286.9 - Fee for processing applications and issuing documentation at land border Ports-of-Entry.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    .../Departure Record, for admission at a land border Port-of-Entry must remit the required fee for issuance of... Card, issued by the DOS, or a passport and combined B-1/B-2 visa and non-biometric BCC (or similar stamp in a passport) issued by the DOS, who is required to be issued Form I-94, Arrival/Departure Record...

  10. 8 CFR 286.9 - Fee for processing applications and issuing documentation at land border Ports-of-Entry.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...), Arrival/Departure Record, for admission at a land border Port-of-Entry must remit the required fee for... Card, issued by the DOS, or a passport and combined B-1/B-2 visa and non-biometric BCC (or similar stamp in a passport) issued by the DOS, who is required to be issued Form I-94, Arrival/Departure Record...

  11. 8 CFR 286.9 - Fee for processing applications and issuing documentation at land border Ports-of-Entry.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    .../Departure Record, for admission at a land border Port-of-Entry must remit the required fee for issuance of... Card, issued by the DOS, or a passport and combined B-1/B-2 visa and non-biometric BCC (or similar stamp in a passport) issued by the DOS, who is required to be issued Form I-94, Arrival/Departure Record...

  12. 8 CFR 286.9 - Fee for processing applications and issuing documentation at land border Ports-of-Entry.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    .../Departure Record, for admission at a land border Port-of-Entry must remit the required fee for issuance of... Card, issued by the DOS, or a passport and combined B-1/B-2 visa and non-biometric BCC (or similar stamp in a passport) issued by the DOS, who is required to be issued Form I-94, Arrival/Departure Record...

  13. Fotometria de grupos compactos de galáxias no infravermelho próximo

    NASA Astrophysics Data System (ADS)

    Brasileiro, F.; Mendes de Oliveira, C.

    2003-08-01

    Apresentamos medidas nas bandas J, H e K de cerca de 90 galáxias em 34 grupos compactos. Através da combinação dos novos dados, com dados obtidos na literatura para a banda B, investigamos como as luminosidades, cores, tamanhos e massas das galáxias em grupos compactos foram afetadas por processos dinâmicos, e como essas diferem de galáxias em ambientes menos densos. Uma comparação dos novos valores obtidos com aqueles listados no catálogo 2MASS, mostram que para 50 galáxias estudadas em comum, as diferenças nas magnitudes J, H e K estão dentro dos erros fotométricos. Através da construção dos diagramas de cor (J-H x H-K e B-H x J-K), percebemos que as galáxias em grupos compactos ocupam posições no diagrama diferentes das posições de galáxias em campo ou em aglomerados, sendo mais parecidas com as posições ocupadas por galáxias HII, ou com excesso de poeira, acreditamos que tal deslocamento é derivado do aumento da taxa de formação estelar.

  14. Diversity of sandflies (Psychodidae: Phlebotominae) captured in sandstone caves from Central Amazonia, Brazil.

    PubMed

    Alves, Veracilda Ribeiro; Freitas, Rui Alves de; Santos, Francisco Lima; Barrett, Toby Vincent

    2011-05-01

    In the present paper we describe the diversity of phlebotomine sandflies collected in three sandstone caves in the municipality of Presidente Figueiredo, state of Amazonas, Brazil. The phlebotomines were captured during 2006 with CDC light traps. Guano samples from inside the Gruta Refúgio do Maruaga were collected to investigate the presence of immature specimens. A total of 2,160 adult phlebotomines representing 15 species were captured. Pintomyia pacae was the dominant species in Gruta dos Animais (1,723 specimens) and Gruta dos Lages (50 specimens) and Deanemyia maruaga new comb (280 specimens) was the dominant species in Gruta Refúgio do Maruaga. A total of 18 guano samples were collected and seven of these samples included immature specimens. A total of 507 immature specimens were captured; 495 of these specimens were larvae and 12 were pupae. The presence of paca (Agouti paca) footprints near Gruta dos Animais and Gruta dos Lages suggests the association of Pi. pacae with this rodent. This finding may explain the abundance of Pi. pacae in these locations, while the species is relatively rare in the forest. Deanemyia maruaga is a cave species that uses guano to breed during its immature stages. Adult specimens of this species are apparently parthenogenetic and autogenous and represent the second record of parthenogenesis for the subfamily Phlebotominae.

  15. Adaptive Suspicious Prevention for Defending DoS Attacks in SDN-Based Convergent Networks

    PubMed Central

    Dao, Nhu-Ngoc; Kim, Joongheon; Park, Minho; Cho, Sungrae

    2016-01-01

    The convergent communication network will play an important role as a single platform to unify heterogeneous networks and integrate emerging technologies and existing legacy networks. Although there have been proposed many feasible solutions, they could not become convergent frameworks since they mainly focused on converting functions between various protocols and interfaces in edge networks, and handling functions for multiple services in core networks, e.g., the Multi-protocol Label Switching (MPLS) technique. Software-defined networking (SDN), on the other hand, is expected to be the ideal future for the convergent network since it can provide a controllable, dynamic, and cost-effective network. However, SDN has an original structural vulnerability behind a lot of advantages, which is the centralized control plane. As the brains of the network, a controller manages the whole network, which is attractive to attackers. In this context, we proposes a novel solution called adaptive suspicious prevention (ASP) mechanism to protect the controller from the Denial of Service (DoS) attacks that could incapacitate an SDN. The ASP is integrated with OpenFlow protocol to detect and prevent DoS attacks effectively. Our comprehensive experimental results show that the ASP enhances the resilience of an SDN network against DoS attacks by up to 38%. PMID:27494411

  16. Adaptive Suspicious Prevention for Defending DoS Attacks in SDN-Based Convergent Networks.

    PubMed

    Dao, Nhu-Ngoc; Kim, Joongheon; Park, Minho; Cho, Sungrae

    2016-01-01

    The convergent communication network will play an important role as a single platform to unify heterogeneous networks and integrate emerging technologies and existing legacy networks. Although there have been proposed many feasible solutions, they could not become convergent frameworks since they mainly focused on converting functions between various protocols and interfaces in edge networks, and handling functions for multiple services in core networks, e.g., the Multi-protocol Label Switching (MPLS) technique. Software-defined networking (SDN), on the other hand, is expected to be the ideal future for the convergent network since it can provide a controllable, dynamic, and cost-effective network. However, SDN has an original structural vulnerability behind a lot of advantages, which is the centralized control plane. As the brains of the network, a controller manages the whole network, which is attractive to attackers. In this context, we proposes a novel solution called adaptive suspicious prevention (ASP) mechanism to protect the controller from the Denial of Service (DoS) attacks that could incapacitate an SDN. The ASP is integrated with OpenFlow protocol to detect and prevent DoS attacks effectively. Our comprehensive experimental results show that the ASP enhances the resilience of an SDN network against DoS attacks by up to 38%.

  17. A semi-metallic layer in detonating nitromethane

    NASA Astrophysics Data System (ADS)

    Reed, Evan; Manaa, Riad; Fried, Laurence; Glaesemann, Kurt; Joannopoulos, John

    2007-06-01

    We present the first ever glimpse behind a detonation front in a chemically reactive quantum molecular dynamics simulation (up to 0.2 ns) of the explosive nitromethane (CH3NO2) represented by the density-functional-based tight-binding method (DFTB). This simulation is enabled by our recently developed multi-scale shock wave molecular dynamics technique (MSST) that opens the door to longer duration simulations by several orders of magnitude. The electronic DOS around the Fermi energy initially increases as metastable material states are produced but then later decreases, perhaps unexpectedly. These changes indicate that the shock front is characterized by an increase in optical thickness followed by a reduction in optical thickness hundreds of picoseconds behind the front, explaining recent experimental observations. We find that a significant population of intermediate metastable molecules are charged and charged species play an important role in the density of states evolution and a possible Mott metal-insulator transition.

  18. Comparative Photoemission Study of Actinide (Am, Pu, Np and U) Metals, Nitrides, and Hydrides

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gouder, Thomas; Seibert, Alice; Rebizant, Jean

    2007-07-01

    Core-level and valence-band spectra of Pu and the other early actinide compounds show remarkable systematics, which can be understood in the framework of final state screening. We compare the early actinide (U, Np, Pu and Am) metals, nitrides and hydrides and a few other specific compounds (PuSe, PuS, PuCx, PuSix) prepared as thin films by sputter deposition. In choosing these systems, we combine inherent 5f band narrowing, due to 5f orbital contraction throughout the actinide series, with variations of the chemical environment in the compounds. Goal of this work was to learn more on the electronic structure of the earlymore » actinide systems and to achieve the correct interpretation of their photoemission spectra. The highly correlated nature of the 5f states in systems, which are on the verge to localization, makes this a challenging task, because of the peculiar interplay between ground state DOS and final-state effects. Their influence can be estimated by doing systematic studies on systems with different (5f) bandwidths. We conclude on the basis of such systematic experiments that final-state effects due to strong e-e correlations in narrow 5f-band systems lead to multiplet like structures, analogous to those observed in the case of systems with localized electron states. Such observations in essentially band-like 5f-systems was first surprising, but the astonishing similarity of photoemission spectra of very different chemical systems (e.g. PuSe, Pu{sub 2}C{sub 3}..) points to a common origin, relating them to atomic features rather than material dependent density of states (DOS) features. (authors)« less

  19. On Field-Effect Photovoltaics: Gate Enhancement of the Power Conversion Efficiency in a Nanotube/Silicon-Nanowire Solar Cell.

    PubMed

    Petterson, Maureen K; Lemaitre, Maxime G; Shen, Yu; Wadhwa, Pooja; Hou, Jie; Vasilyeva, Svetlana V; Kravchenko, Ivan I; Rinzler, Andrew G

    2015-09-30

    Recent years have seen a resurgence of interest in crystalline silicon Schottky junction solar cells distinguished by the use of low density of electronic states (DOS) nanocarbons (nanotubes, graphene) as the metal contacting the Si. Recently, unprecedented modulation of the power conversion efficiency in a single material system has been demonstrated in such cells by the use of electronic gating. The gate field induced Fermi level shift in the low-DOS carbon serves to enhance the junction built-in potential, while a gate field induced inversion layer at the Si surface, in regions remote from the junction, keeps the photocarriers well separated there, avoiding recombination at surface traps and defects (a key loss mechanism). Here, we extend these results into the third dimension of a vertical Si nanowire array solar cell. A single wall carbon nanotube layer engineered to contact virtually each n-Si nanowire tip extracts the minority carriers, while an ionic liquid electrolytic gate drives the nanowire body into inversion. The enhanced light absorption of the vertical forest cell, at 100 mW/cm(2) AM1.5G illumination, results in a short-circuit current density of 35 mA/cm(2) and associated power conversion efficiency of 15%. These results highlight the use of local fields as opposed to surface passivation as a means of avoiding front surface recombination. A deleterious electrochemical reaction of the silicon due to the electrolyte gating is shown to be caused by oxygen/water entrained in the ionic liquid electrolyte. While encapsulation can avoid the issue, a nonencapsulation-based approach is also implemented.

  20. A new species of Eimeria Schneider, 1875 from the Serra dos Órgãos National Park, Rio de Janeiro, Brazil, with notes on its endogenous development in the montane grass mouse, Akodon montensis Thomas, 1913 (Rodentia: Sigmodontinae).

    PubMed

    de Santana Miglionico, Marcos Tobias; Viana, Lúcio André; Barbosa, Helene Santos; Mota, Ester Maria; da Costa Neto, Sócrates Fraga; Frazão-Teixeira, Edwards; D'Andrea, Paulo Sergio

    2018-02-01

    A total of 53 specimens of the montane grass mouse, Akodon montensis Thomas, 1913 were collected in the Serra dos Órgãos National Park (SONP) in November 2014 and July 2015. The fecal material was analyzed, and a prevalence of 7.5% was recorded for a new coccidian species of the genus Eimeria Schneider, 1875, with part of its endogenous development recorded in the small intestine. The oocysts of a new coccidian species of genus Eimeria are ellipsoidal to subspherical. The wall is bi-layered, c. 1.5 μm (1.3-1.6 μm) thick, outer layer rough. Oocyst (n = 126) mean length is 25.3 μm (21.0-28.0 μm), with a width of 20.2 μm (17.0-22.0 μm) and mean length/width (L:W) ratio of 1.3 (1.2-1.4). Polar granule is present, with the oocyst residuum as a large spherical to subspherical globule. Sporocyst shape (n = 126) is ellipsoidal, with a mean length of 11.8 μm (9.3-14.4 μm), width of 7.9 μm (6.7-9.3 μm), and mean L:W ratio of 1.5 (1.4-1.7). Sporocysts with nipple-like Stieda body and sub-Stieda body are absent. A sporocyst residuum formed by several globules, usually along the sporocyst wall. This is the first record of Eimeria in the montane grass mouse from Brazil.

  1. A Diverging DOS Strategy Using an Allene-Containing Tryptophan Scaffold and a Library Design that Maximizes Biologically Relevant Chemical Space While Minimizing the Number of Compounds

    PubMed Central

    Painter, Thomas O.; Wang, Lirong; Majumder, Supriyo; Xie, Xiang-Qun; Brummond, Kay M.

    2011-01-01

    A diverging diversity-oriented synthesis (DOS) strategy using an allene-containing tryptophan as a key starting material was investigated. An allene-yne substituted derivative of tryptophan 12 gave indolylmethylazabicyclooctadiene 17 when subjected to a microwave-assisted allenic [2 + 2] cycloaddition reaction. This same tryptophan-derived precursor afforded an indolylmethyldihydrocyclopentapyridinone 14 when subjected to a rhodium(I)-catalyzed cyclocarbonylation reaction and an indolylmethylpyrrolidinocyclopentenones 16 when reacted with molybdenum hexacarbonyl. Construction of allenic tetrahydro-β-carboline scaffolds via a Pictet-Spengler reaction and subsequent silver(I)-catalyzed cycloisomerization afforded tetrahydroindolizinoindoles (21). Attachment of allene and alkyne groups to the tetrahydro-β-carboline followed by a microwave-assisted allenic [2 + 2] cycloaddition reaction provided tetrahydrocyclobutaindoloquinolizinones 24 and the tetrahydrocyclopentenone indolizinoindolone 26 when reacted with molybdenum hexacarbonyl. These six scaffolds were used as a template for the construction of a virtual library of 11,748 compounds employing 44 indoles, 12 aldehydes, and 51 alkynes. Diversity analyses using a combination of cell-based chemistry space computations using BCUT (Burden (B) CAS (C) Pearlman at the University of Texas (UT)) metrics and Tanimoto coefficient (Tc) similarity calculations using two-dimensional (2D) fingerprints showed that the compounds in the virtual library occupied new chemical space when compared to the 327,000 compounds in the molecular libraries small molecule repository (MLSMR). A subset of fifty-three compounds was identified from the virtual library using the DVS package of Sybyl 8.0; this subset represents the most diverse compounds within the chemical space defined by these compounds and will be synthesized and screened for biological activity. PMID:21332123

  2. On Field-Effect Photovoltaics: Gate Enhancement of the Power Conversion Efficiency in a Nanotube/Silicon-Nanowire Solar Cell

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Petterson, Maureen K.; Lemaitre, Maxime G.; Shen, Yu

    Recent years have seen a resurgence of interest in crystalline silicon Schottky junction solar cells distinguished by the use of low density of electronic states (DOS) nanocarbons (nanotubes, graphene) as the metal contacting the Si. Recently, unprecedented modulation of the power conversion efficiency in a single material system has been demonstrated in such cells by the use of electronic gating. The gate field induced Fermi level shift in the low-DOS carbon serves to enhance the junction built-in potential, while a gate field induced inversion layer at the Si surface, in regions remote from the junction, keeps the photocarriers well separatedmore » there, avoiding recombination at surface traps and defects (a key loss mechanism). Here, we extend these results into the third dimension of a vertical Si nanowire array solar cell. A single wall carbon nanotube layer engineered to contact virtually each n-Si nanowire tip extracts the minority carriers, while an ionic liquid electrolytic gate drives the nanowire body into inversion. The enhanced light absorption of the vertical forest cell, at 100 mW/cm 2 AM1.5G illumination, results in a short-circuit current density of 35 mA/cm 2 and associated power conversion efficiency of 15%. These results highlight the use of local fields as opposed to surface passivation as a means of avoiding front surface recombination. Finally, a deleterious electrochemical reaction of the silicon due to the electrolyte gating is shown to be caused by oxygen/water entrained in the ionic liquid electrolyte. While encapsulation can avoid the issue, a nonencapsulation-based approach is also implemented.« less

  3. On Field-Effect Photovoltaics: Gate Enhancement of the Power Conversion Efficiency in a Nanotube/Silicon-Nanowire Solar Cell

    DOE PAGES

    Petterson, Maureen K.; Lemaitre, Maxime G.; Shen, Yu; ...

    2015-09-09

    Recent years have seen a resurgence of interest in crystalline silicon Schottky junction solar cells distinguished by the use of low density of electronic states (DOS) nanocarbons (nanotubes, graphene) as the metal contacting the Si. Recently, unprecedented modulation of the power conversion efficiency in a single material system has been demonstrated in such cells by the use of electronic gating. The gate field induced Fermi level shift in the low-DOS carbon serves to enhance the junction built-in potential, while a gate field induced inversion layer at the Si surface, in regions remote from the junction, keeps the photocarriers well separatedmore » there, avoiding recombination at surface traps and defects (a key loss mechanism). Here, we extend these results into the third dimension of a vertical Si nanowire array solar cell. A single wall carbon nanotube layer engineered to contact virtually each n-Si nanowire tip extracts the minority carriers, while an ionic liquid electrolytic gate drives the nanowire body into inversion. The enhanced light absorption of the vertical forest cell, at 100 mW/cm 2 AM1.5G illumination, results in a short-circuit current density of 35 mA/cm 2 and associated power conversion efficiency of 15%. These results highlight the use of local fields as opposed to surface passivation as a means of avoiding front surface recombination. Finally, a deleterious electrochemical reaction of the silicon due to the electrolyte gating is shown to be caused by oxygen/water entrained in the ionic liquid electrolyte. While encapsulation can avoid the issue, a nonencapsulation-based approach is also implemented.« less

  4. Hemocompatibility Comparison of Biomedical Grade Polymers Using Rabbit Thrombogenicity Model for Preparing Nonthrombogenic Nitric Oxide Releasing Surfaces

    PubMed Central

    Handa, Hitesh; Major, Terry C.; Brisbois, Elizabeth J.; Amoako, Kagya A.; Meyerhoff, Mark E.; Bartlett, Robert H.

    2014-01-01

    Nitric oxide (NO) is an endogenous vasodilator as well as natural inhibitor of platelet adhesion/activation. Nitric oxide releasing (NOrel) materials can be prepared by doping an NO donor species, such as diazeniumdiolated dibutylhexanediamine (DBHD/N2O2), within a polymer coating. The inherent hemocompatibility properties of the base polymer can also influence the efficiency of such NO release coatings. In this study, four biomedical grade polymers were evaluated in a 4 h rabbit model of thrombogenicity for their effects on extracorporeal circuit thrombus formation and circulating platelet count. At the end of 4 h, Elast-Eon E2As was found to preserve 58% of baseline platelets versus 48, 40, and 47% for PVC/DOS, Tecophilic SP-60D-60, and Tecoflex SG80A, respectively. Elast-Eon also had significantly lower clot area of 5.2 cm2 compared to 6.7, 6.1, and 6.9 cm2 for PVC/DOS, SP-60D-60, and SG80A, respectively. Based on the results obtained for the base polymer comparison study, DBHD/N2O2-doped E2As was evaluated in short-term (4 h) rabbit studies to observe the NO effects on prevention of clotting and preservation of platelet function. Platelet preservation for this optimal NO release formulation was 97% of baseline after 4 h, and clot area was 0.9 cm2 compared to 5.2 cm2 for controls, demonstrating that combining E2As with NO release provides a truly advanced hemocompatible polymer coating for extracorporeal circuits and potentially other blood contacting applications. PMID:24634777

  5. Iraqi Police Development Program: Opportunities for Improved Program Accountability and Budget Transparency

    DTIC Science & Technology

    2011-10-24

    makes three recommendations to the Secretary of State, highlighting the need for (1) an adequate current assessment of the Iraqi police forces, (2...with documents obtained from other sources, allowed us to determine that: • DoS does not have a current assessment of Iraqi police forces...capabilities upon which to base its program. Such an assessment is essential for effective program targeting. Further, DoS does not have a sufficiently

  6. Transforming the Department of State: Adapting Operational Capacities and Capabilities to the Post-9/11 Reality, Evolving Interagency Responsibilities, and the Challenges of the 21st Century

    DTIC Science & Technology

    2006-04-14

    combination of the Strategic Plan, MPPs, and BPPs goals, along with performance, and accountability plans. Three other documents are inherently important...DOS Strategic Plan, Mission Performance Plan (MPP), Bureau Performance Plan ( BPP ). NSC representation, POLADs, Embassy Country Teams, and...the world. DOS Strategic Plan, Mission Performance Plan (MPP), Bureau Performance Plan ( BPP ). NSC representation, POLADs, Exchange

  7. Configuration of Wireless Cooperative/Sensor Networks

    DTIC Science & Technology

    2008-05-25

    WSN), the advantages of cooperation can be further exploited by optimally allocating the energy and bandwidth resources among users based on the... consumption and extend system lifetime [Sin98]. The implementation of a minimum energy routing protocol is discussed in [Dos02a, Dos02b]. An online...power consumption in the network given the required SER at the destination. For example, with source power Ps=20dB, the EP algorithm requires one relay

  8. Video movie making using remote procedure calls and 4BSD Unix sockets on Unix, UNICOS, and MS-DOS systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Robertson, D.W.; Johnston, W.E.; Hall, D.E.

    1990-03-01

    We describe the use of the Sun Remote Procedure Call and Unix socket interprocess communication mechanisms to provide the network transport for a distributed, client-server based, image handling system. Clients run under Unix or UNICOS and servers run under Unix or MS-DOS. The use of remote procedure calls across local or wide-area networks to make video movies is addressed.

  9. 32 CFR Appendix C to Part 197 - Procedures for the Department of State (DoS) Foreign Relations of the United States (FRUS) Series

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 2 2011-07-01 2011-07-01 false Procedures for the Department of State (DoS) Foreign Relations of the United States (FRUS) Series C Appendix C to Part 197 National Defense Department... RESEARCH IN THE FILES OF THE OFFICE OF THE SECRETARY OF DEFENSE (OSD) Pt. 197, App. C Appendix C to Part...

  10. Governance: The Mission Ingredient in Security Cooperation

    DTIC Science & Technology

    2017-06-09

    assistance guiding principle of “do-no-harm,” should be included in the future DOS guidance. Seven do-no-harm lessons include: (1) norms and... principle of “do-no-harm.” 15. SUBJECT TERMS Security cooperation, security assistance, defense institution building, USAID, best practices...foreign assistance guiding principle of “do-no-harm,” should be included in the future DOS guidance. Seven do-no-harm lessons include: (1) norms and

  11. User's guide for SYSTUM-1 (Version 2.0): A simulator of growth trends in young stands under management in California and Oregon

    Treesearch

    Martin W. Ritchie; Robert F. Powers

    1993-01-01

    SYSTUM-1 is an individual-tree/distance-independent simulator developed for use in young plantations in California and southern Oregon. The program was developed to run under the DOS operating system and requires DOS 3.0 or higher running on an 8086 or higher processor. The simulator is designed to provide a link with existing PC-based simulators (CACTOS and ORGANON)...

  12. Diverted organic synthesis (DOS): accessing a new, natural product inspired, neurotrophically active scaffold through an intramolecular Pauson-Khand reaction.

    PubMed

    Mehta, Goverdhan; Samineni, Ramesh; Srihari, Pabbaraja; Reddy, R Gajendra; Chakravarty, Sumana

    2012-09-14

    Drawing inspiration from the impressive neurotrophic activity exhibited by the natural product paecilomycine A, we have designed a new natural product-like scaffold employing an intramolecular Pauson-Khand reaction. Several compounds based on the new designer scaffold exhibited promising neurotrophic activity and are worthy of further biological evaluation. Our findings also highlight the importance of a DOS strategy in creating useful therapeutical leads.

  13. “Click, Click, Cyclize”: A DOS Approach to Sultams Utilizing Vinyl Sulfonamide Linchpins

    PubMed Central

    Zhou, Aihua; Rayabarapu, Dinesh; Hanson, Paul R.

    2009-01-01

    A diversity-oriented synthesis (DOS) strategy termed “Click, Click, Cyclize” is reported. This approach relies on functional group (FG) pairing between a vinyl sulfonamide and an array of functional groups to synthesize skeletally diverse sultams. Several FG pairing pathways on central tertiary vinyl sulfonamide linchpins have been developed including intramolecular Heck, aza-Michael, ring-closing enyne metathesis, Pauson—Khand, and chemoselective oxidation/Baylis—Hillman reactions. PMID:19115841

  14. Density-of-state oscillation of quasiparticle excitation in the spin density wave phase of (TMTSF)2ClO4.

    PubMed

    Uji, S; Kimata, M; Moriyama, S; Yamada, J; Graf, D; Brooks, J S

    2010-12-31

    Systematic measurements of the magnetocaloric effect, heat capacity, and magnetic torque under a high magnetic field up to 35 T are performed in the spin density wave (SDW) phase of a quasi-one-dimensional organic conductor (TMTSF)2ClO4. In the SDW phase above 26 T, where the quantum Hall effect is broken, rapid oscillations (ROs) in these thermodynamic quantities are observed, which provides clear evidence of the density-of-state (DOS) oscillation near the Fermi level. The resistance is semiconducting and the heat capacity divided by temperature is extrapolated to zero at 0 K in the SDW phase, showing that all the energy bands are gapped, and there is no DOS at the Fermi level. The results show that the ROs are ascribed to the DOS oscillation of the quasiparticle excitation.

  15. Rheological and Magnetorheological Behaviour of Some Magnetic Fluids on Polar and Nonpolar Carrier Liquids

    NASA Astrophysics Data System (ADS)

    Bălău, Oana; Bica, Doina; Koneracka, Martina; Kopčansky, Peter; Susan-Resiga, Daniela; Vékás, Ladislau

    Rheological and magnetorheological behaviour of monolayer and double layer sterically stabilized magnetic fluids, with transformer oil (UTR), diloctilsebacate (DOS), heptanol (Hept), pentanol (Pent) and water (W) as carrier liquids, were investigated. The data for volumic concentration dependence of dynamic viscosity of high colloidal stability UTR, DOS, Hept and Pent samples are particularly well fitted by the formulas given by Vand (1948) and Chow (1994). The Chow type dependence proved its universal character as the viscosity data for dilution series of various magnetic fluids are well fitted by the same curve, regardless the nonpolar or polar charcater of the sample. The magnetorheological effect measured for low and medium concentration water based magnetic fluids is much higher, due to agglomerate formation process, than the corresponding values obtained for the well stabilized UTR, DOS, Hept and Pent samples, even at very high volumic fraction of magnetic nanoparticles.

  16. Mott-Hubbard transition and Anderson localization: A generalized dynamical mean-field theory approach

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kuchinskii, E. Z.; Nekrasov, I. A.; Sadovskii, M. V.

    The DOS, the dynamic (optical) conductivity, and the phase diagram of a strongly correlated and strongly disordered paramagnetic Anderson-Hubbard model are analyzed within the generalized dynamical mean field theory (DMFT + {sigma} approximation). Strong correlations are taken into account by the DMFT, and disorder is taken into account via an appropriate generalization of the self-consistent theory of localization. The DMFT effective single-impurity problem is solved by a numerical renormalization group (NRG); we consider the three-dimensional system with a semielliptic DOS. The correlated metal, Mott insulator, and correlated Anderson insulator phases are identified via the evolution of the DOS and dynamicmore » conductivity, demonstrating both the Mott-Hubbard and Anderson metal-insulator transition and allowing the construction of the complete zero-temperature phase diagram of the Anderson-Hubbard model. Rather unusual is the possibility of a disorder-induced Mott insulator-to-metal transition.« less

  17. Structure of V2AlC studied by theory and experiment

    NASA Astrophysics Data System (ADS)

    Schneider, Jochen M.; Mertens, Raphael; Music, Denis

    2006-01-01

    We have studied V2AlC (space group P63/mmc, prototype Cr2AlC) by ab initio calculations. The density of states (DOS) of V2AlC for antiferromagnetic, ferromagnetic, and paramagnetic configurations have been discussed. According to the analysis of DOS and cohesive energy, no significant stability differences between spin-polarized and non-spin-polarized configurations were found. Based on the partial DOS analysis, V2AlC can be classified as a strongly coupled nanolaminate according to our previous work [Z. Sun, D. Music, R. Ahuja, S. Li, and J. M. Schneider, Phys. Rev. B 70, 092102 (2004)]. Furthermore, this phase has been synthesized in the form of thin films by magnetron sputtering. The equilibrium volume, determined by x-ray diffraction, is in good agreement with the theoretical data, implying that ab initio calculations provide an accurate description of V2AlC.

  18. Universal Non-Debye Scaling in the Density of States of Amorphous Solids.

    PubMed

    Charbonneau, Patrick; Corwin, Eric I; Parisi, Giorgio; Poncet, Alexis; Zamponi, Francesco

    2016-07-22

    At the jamming transition, amorphous packings are known to display anomalous vibrational modes with a density of states (DOS) that remains constant at low frequency. The scaling of the DOS at higher packing fractions remains, however, unclear. One might expect to find a simple Debye scaling, but recent results from effective medium theory and the exact solution of mean-field models both predict an anomalous, non-Debye scaling. Being mean-field in nature, however, these solutions are only strictly valid in the limit of infinite spatial dimension, and it is unclear what value they have for finite-dimensional systems. Here, we study packings of soft spheres in dimensions 3 through 7 and find, away from jamming, a universal non-Debye scaling of the DOS that is consistent with the mean-field predictions. We also consider how the soft mode participation ratio evolves as dimension increases.

  19. Phonon anharmonicity of monoclinic zirconia and yttrium-stabilized zirconia

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li, Chen W.; Smith, Hillary L.; Lan, Tian

    2015-04-13

    Inelastic neutron scattering measurements on monoclinic zirconia (ZrO 2) and 8 mol% yttrium-stabilized zirconia were performed at temperatures from 300 to 1373 ωK. We reported temperature-dependent phonon densities of states (DOS) and Raman spectra obtained at elevated temperatures. First-principles lattice dynamics calculations with density functional theory gave total and partial phonon DOS curves and mode Grüneisen parameters. These mode Grüneisen parameters were used to predict the experimental temperature dependence of the phonon DOS with partial success. However, substantial anharmonicity was found at elevated temperatures, especially for phonon modes dominated by the motions of oxygen atoms. Yttrium-stabilized zirconia (YSZ) was somewhatmore » more anharmonic and had a broader phonon spectrum at low temperatures, owing in part to defects in its structure. YSZ also has a larger vibrational entropy than monoclinic zirconia.« less

  20. Broadening of Distribution of Trap States in PbS Quantum Dot Field-Effect Transistors with High-k Dielectrics

    PubMed Central

    2017-01-01

    We perform a quantitative analysis of the trap density of states (trap DOS) in PbS quantum dot field-effect transistors (QD-FETs), which utilize several polymer gate insulators with a wide range of dielectric constants. With increasing gate dielectric constant, we observe increasing trap DOS close to the lowest unoccupied molecular orbital (LUMO) of the QDs. In addition, this increase is also consistently followed by broadening of the trap DOS. We rationalize that the increase and broadening of the spectral trap distribution originate from dipolar disorder as well as polaronic interactions, which are appearing at strong dielectric polarization. Interestingly, the increased polaron-induced traps do not show any negative effect on the charge carrier mobility in our QD devices at the highest applied gate voltage, giving the possibility to fabricate efficient low-voltage QD devices without suppressing carrier transport. PMID:28084725

  1. Chemotaxis cluster 1 proteins form cytoplasmic arrays in Vibrio cholerae and are stabilized by a double signaling domain receptor DosM.

    PubMed

    Briegel, Ariane; Ortega, Davi R; Mann, Petra; Kjær, Andreas; Ringgaard, Simon; Jensen, Grant J

    2016-09-13

    Nearly all motile bacterial cells use a highly sensitive and adaptable sensory system to detect changes in nutrient concentrations in the environment and guide their movements toward attractants and away from repellents. The best-studied bacterial chemoreceptor arrays are membrane-bound. Many motile bacteria contain one or more additional, sometimes purely cytoplasmic, chemoreceptor systems. Vibrio cholerae contains three chemotaxis clusters (I, II, and III). Here, using electron cryotomography, we explore V. cholerae's cytoplasmic chemoreceptor array and establish that it is formed by proteins from cluster I. We further identify a chemoreceptor with an unusual domain architecture, DosM, which is essential for formation of the cytoplasmic arrays. DosM contains two signaling domains and spans the two-layered cytoplasmic arrays. Finally, we present evidence suggesting that this type of receptor is important for the structural stability of the cytoplasmic array.

  2. Reagent-based DOS: developing a diastereoselective methodology to access spirocyclic- and fused heterocyclic ring systems.

    PubMed

    Damerla, V Surendra Babu; Tulluri, Chiranjeevi; Gundla, Rambabu; Naviri, Lava; Adepally, Uma; Iyer, Pravin S; Murthy, Y L N; Prabhakar, Nampally; Sen, Subhabrata

    2012-10-01

    Herein, we report a diversity-oriented-synthesis (DOS) approach for the synthesis of biologically relevant molecular scaffolds. Our methodology enables the facile synthesis of fused N-heterocycles, spirooxoindolones, tetrahydroquinolines, and fused N-heterocycles. The two-step sequence starts with a chiral-bicyclic-lactam-directed enolate-addition/substitution step. This step is followed by a ring-closure onto the built-in scaffold electrophile, thereby leading to stereoselective carbocycle- and spirocycle-formation. We used in silico tools to calibrate our compounds with respect to chemical diversity and selected drug-like properties. We evaluated the biological significance of our scaffolds by screening them in two cancer cell-lines. In summary, our DOS methodology affords new, diverse scaffolds, thereby resulting in compounds that may have significance in medicinal chemistry. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Análise dos Conceitos Astronômicos Apresentados por Professores de Algumas Escolas Estaduais Brasileiras

    NASA Astrophysics Data System (ADS)

    Voelzke, Marcos Rincon; Gonzaga, Edson Pereira

    2011-12-01

    A razão para o desenvolvimento deste trabalho baseia-se no fato de que muitos professores da Educação Básica (EB) não lidam com conceitos relacionados à astronomia, e quando o fazem eles simplesmente seguem livros didáticos que podem conter erros conceituais. Como é de conhecimento geral a astronomia é um dos conteúdos a serem ensinados na EB fazendo parte dos Parâmetros Curriculares Nacionais e das Propostas Curriculares do Estado de São Paulo, mas é um fato, que vários pesquisadores apontam, a existência de muitos problemas no ensino da astronomia. Com o propósito de minimizar algumas dessas deficiências foi realizado um trabalho de pesquisa com a utilização de questionários pré e pós pesquisa, para tanto foi desenvolvido um Curso de Extensão Universitária para professores da Diretoria de Ensino Regional (DE) que abrange Mauá, Ribeirão Pires e Rio Grande da Serra (no Estado de São Paulo) com os seguintes objetivos: levantar concepções alternativas; subsidiar os professores por meio de palestras, debates e workshops, e verificar o sucesso da aprendizagem após o curso, adotando-se como referência, para a análise dos resultados, os dicionários de Língua Portuguesa (FERREIRA, 2004) e Enciclopédico de Astronomia e Astronáutica (MOURĀO, 1995). Portanto, dezesseis questões foram aplicadas antes e após o curso, assim pode-se verificar após a pesquisa que 100,0% dos professores sabiam os nomes das fases da Lua, 97,0% entenderam que o Sistema Solar é composto por oito planetas, 78,1% foram capazes de explicar como ocorre um eclipse lunar, um eclipse solar e um solstício, 72,7% sabiam como explicar a ocorrência das estações do ano; 64,5% explicaram corretamente a ocorrência do equinócio, 89,7% foram capazes de definir adequadamente o termo cometa; 63,6% definiram asteróide, 54,5% meteoro, 58,1% galáxia, e 42,4% planeta. Os resultados obtidos indicam uma aprendizagem significativa por parte dos participantes.

  4. Diversity-Oriented Synthesis as a Strategy for Fragment Evolution against GSK3β.

    PubMed

    Wang, Yikai; Wach, Jean-Yves; Sheehan, Patrick; Zhong, Cheng; Zhan, Chenyang; Harris, Richard; Almo, Steven C; Bishop, Joshua; Haggarty, Stephen J; Ramek, Alexander; Berry, Kayla N; O'Herin, Conor; Koehler, Angela N; Hung, Alvin W; Young, Damian W

    2016-09-08

    Traditional fragment-based drug discovery (FBDD) relies heavily on structural analysis of the hits bound to their targets. Herein, we present a complementary approach based on diversity-oriented synthesis (DOS). A DOS-based fragment collection was able to produce initial hit compounds against the target GSK3β, allow the systematic synthesis of related fragment analogues to explore fragment-level structure-activity relationship, and finally lead to the synthesis of a more potent compound.

  5. Identification and In-vivo Characterization of a Novel OhrR Transcriptional Regulator in Burkholderia xenovorans LB400

    DOE PAGES

    Nguyen, Tinh T.; Martí-Arbona, Ricardo; Hall, Richard S.; ...

    2013-05-21

    Transcriptional regulators (TRs) are an important and versatile group of proteins, yet very little progress has been achieved towards the discovery and annotation of their biological functions. We have characterized a previously unknown organic hydroperoxide resistance regulator from Burkholderia xenovoransLB400, Bxe_B2842, which is homologous to E. coli’s OhrR. Bxe_B2842 regulates the expression of an organic hydroperoxide resistance protein (OsmC). We utilized frontal affinity chromatography coupled with mass spectrometry (FAC-MS) and electrophoretic mobility gel shift assays (EMSA) to identify and characterize the possible effectors of the regulation by Bxe_B2842. Without an effector, Bxe_B2842 binds a DNA operator sequence (DOS) upstream ofmore » osmC. FAC-MS results suggest that 2-aminophenol binds to the protein and is potentially an effector molecule. EMSA analysis shows that 2-aminophenol also attenuates the Bxe_B2842’s affinity for its DOS. EMSA analysis also shows that organic peroxides attenuate Bxe_B2842/DOS affinity, suggesting that binding of the TR to its DOS is regulated by the two-cysteine mechanism, common to TRs in this family. Bxe_B2842 is the first OhrR TR to have both oxidative and effector-binding mechanisms of regulation. Our paper reveals further mechanistic diversity TR mediated gene regulation and provides insights into methods for function discovery of TRs.« less

  6. Biomarcadores de função endotelial em doenças cardiovasculares: hipertensão

    PubMed Central

    Neves, Josynaria Araújo; Neves, Josyanne Araújo; Oliveira, Rita de Cássia Meneses

    2016-01-01

    Resumo A incidência de hipertensão arterial sistêmica está aumentando mundialmente. Sua prevenção baseia-se na identificação dos hipertensos. Atualmente, biomarcadores são utilizados com fins de diagnosticar, estratificar e prognosticar doenças. Neste estudo, objetivou-se revisar artigos dos últimos cinco anos relacionados a biomarcadores nas doenças cardiovasculares. Pesquisaram-se dados de PubMed, SciELO, Science Direct e MEDLINE, mediante as palavras-chave: hipertensão arterial, biomarcadores cardiovasculares, óxido nítrico, função endotelial e dimetilarginina assimétrica. Os estudos levantados mostram que as doenças cardiovasculares possuem uma etiologia complexa. Neste artigo, evidenciaram-se interações entre o óxido nítrico e a dimetilarginina assimétrica na regulação, no metabolismo e na determinação dos níveis intracelulares, e reviram-se outros biomarcadores relacionados à hipertensão. Alguns estudos indicam os biomarcadores como uma ferramenta útil na predição de eventos cardíacos, e outros reportam que eles contribuem pouco para a avaliação. A seleção e combinação desses pode ser uma alternativa para validar o uso dos biomarcadores devido à pouca especificidade existente para diagnosticar a hipertensão. PMID:29930594

  7. An obligately aerobic soil bacterium activates fermentative hydrogen production to survive reductive stress during hypoxia.

    PubMed

    Berney, Michael; Greening, Chris; Conrad, Ralf; Jacobs, William R; Cook, Gregory M

    2014-08-05

    Oxygen availability is a major factor and evolutionary force determining the metabolic strategy of bacteria colonizing an environmental niche. In the soil, conditions can switch rapidly between oxia and anoxia, forcing soil bacteria to remodel their energy metabolism accordingly. Mycobacterium is a dominant genus in the soil, and all its species are obligate aerobes. Here we show that an obligate aerobe, the soil actinomycete Mycobacterium smegmatis, adopts an anaerobe-type strategy by activating fermentative hydrogen production to adapt to hypoxia. This process is controlled by the two-component system DosR-DosS/DosT, an oxygen and redox sensor that is well conserved in mycobacteria. We show that DosR tightly regulates the two [NiFe]-hydrogenases: Hyd3 (MSMEG_3931-3928) and Hyd2 (MSMEG_2719-2718). Using genetic manipulation and high-sensitivity GC, we demonstrate that Hyd3 facilitates the evolution of H2 when oxygen is depleted. Combined activity of Hyd2 and Hyd3 was necessary to maintain an optimal NAD(+)/NADH ratio and enhanced adaptation to and survival of hypoxia. We demonstrate that fermentatively-produced hydrogen can be recycled when fumarate or oxygen become available, suggesting Mycobacterium smegmatis can switch between fermentation, anaerobic respiration, and aerobic respiration. Hydrogen metabolism enables this obligate aerobe to rapidly meet its energetic needs when switching between microoxic and anoxic conditions and provides a competitive advantage in low oxygen environments.

  8. Dysfunction Screening in Experimental Arteriovenous Grafts for Hemodialysis Using Fractional-Order Extractor and Color Relation Analysis.

    PubMed

    Wu, Ming-Jui; Chen, Wei-Ling; Kan, Chung-Dann; Yu, Fan-Ming; Wang, Su-Chin; Lin, Hsiu-Hui; Lin, Chia-Hung

    2015-12-01

    In physical examinations, hemodialysis access stenosis leading to dysfunction occurs at the venous anastomosis site or the outflow vein. Information from the inflow stenosis, such as blood pressure, pressure drop, and flow resistance increases, allows dysfunction screening from the stage of early clots and thrombosis to the progression of outflow stenosis. Therefore, this study proposes dysfunction screening model in experimental arteriovenous grafts (AVGs) using the fractional-order extractor (FOE) and the color relation analysis (CRA). A Sprott system was designed using an FOE to quantify the differences in transverse vibration pressures between the inflow and outflow sites of an AVG. Experimental analysis revealed that the degree of stenosis (DOS) correlated with an increase in fractional-order dynamic errors (FODEs). Exponential regression was used to fit a non-linear curve and can be used to quantify the relationship between the FODEs and DOS (R (2) = 0.8064). The specific ranges were used to evaluate the stenosis degree, such as DOS: <50, 50-80, and >80%. A CRA-based screening method was derived from the hue angle-saturation-value color model, which describes perceptual color relationships for the DOS. It has a flexibility inference manner with color visualization to represent the different stenosis degrees, which has average accuracy >90% superior to the traditional methods. This in vitro experimental study demonstrated that the proposed model can be used for dysfunction screening in stenotic AVGs.

  9. Fish skin bacteria: Colonial and cellular hydrophobicity.

    PubMed

    Sar, N; Rosenberg, E

    1987-05-01

    Bacteria were desorbed from the skin of healthy, fast-swimming fish by several procedures, including brief exposure to sonic oscillation and treatment with nontoxic surface active agents. The surface properties of these bacteria were studied by measuring their adhesion to hexadecane, as well as by a newly developed, simple method for studying the hydrophobicity of bacterial lawns. This method, referred to as the "Direction of Spreading" (DOS) method, consists of recording the direction to which a water drop spreads when introduced at the border between bacterial lawns and other surfaces. Of the 13 fish skin isolates examined, two strains were as hydrophobic as polystyrene by the DOS method. Suspended cells of one of these strains adhered strongly to hexadecane (84%), whereas cells of the other strain adhered poorly (13%). Another strain which was almost as hydrophobic as polystyrene by the DOS method did not adhere to hexadecane at all. Similarly, lawns of three other strains were more hydrophobic than glass by the DOS method, but cell suspensions prepared from these colonies showed little or no adhesion to hexadecane. The high colonial but relatively low cellular hydrophobicity could be due to a hydrophobic slime that is removed during the suspension and washing procedures. The possibility that specific bacteria assist in fish locomotion by changing the surface properties of the fish skin and by producing drag-reducing polymers is discussed.

  10. En la búsqueda de características en eyecciones coronales de masa que discriminen entre dos paradigmas físicos en modelos de ECMs

    NASA Astrophysics Data System (ADS)

    Paissan, G.; Stenborg, G.; Rovira, M.

    Se conocen tres diferentes fenómenos de gran escala que ocurren en la atmósfera solar, denominados eyecciones coronales de masa (ECMs), protuberancias eruptivas y grandes fulguraciones de dos bandas. Estos fenómenos están estrechamente relacionados y podrían ser distintas manifestaciones de un único proceso físico. Las ECMs son definidas como eyecciones de gran escala de masa y flujo magnético desde la baja corona al espacio interplanetario. Desde su descubrimiento en los '70, muchos modelos han sido propuestos para explicar su origen y evolución. La explicación física de las ECMs es un tema de debate intenso. No obstante, los modelos pueden sintetizarse en dos grandes grupos: 1) los modelos de inyección de flujo y 2) los modelos de almacenamiento y liberación. En este trabajo, se presentan los estudios realizados con una serie de eventos observados con el coronógrafo MICA (Mirror Coronograph for Argentina), el telescopio en H-alfa HASTA (H-alpha Solar Telescope for Argentina) y los coronógrafos C2 y C3 de la sonda SOHO (Solar and Heliospheric Observatory). Los eventos que pudieron ser identificados como ECMs son contrastados dentro del esquema de los dos paradigmas teóricos propuestos.

  11. Comparison of anaesthesia 'Day 1 skills' expectations between veterinary anaesthetists and general practitioners.

    PubMed

    Duncan, J C; Ross, M; Rhind, S; Clutton, E; Shaw, D J

    2015-02-28

    Day One Skills (DOS) were introduced by the Royal College of Veterinary Surgeons (RCVS) in 2006 as a guideline for minimum skills required by a veterinary graduate. However, the RCVS anaesthesia DOS are broad and do not specify differences in skills required for different species. The aims of this study were: (1) to determine which anaesthesia skills were considered essential for day one practice by UK-based veterinary practitioners (GPs) and anaesthetists; and (2) to explore current opinions on veterinary undergraduate anaesthesia training. Questionnaires for veterinary GPs (QGPs) and veterinary anaesthetists (QVAs) were developed which asked general information on expectations of anaesthesia skills as well as specific expectations for the common veterinary species. Fifty-five UK-based members of the Association of Veterinary Anaesthetists responded, with a random sample of veterinary practices stratified by UK county generating 234 responses and a convenience sample targeted at more specialist veterinary specialities in the UK generating 161 responses. There was close overall agreement between the two groups of GPs and anaesthetists on essential anaesthesia DOS. However, expectations varied with species-greatest in cats and dogs, lowest in exotics. Many respondents commented that new veterinary graduates lack practical skills and should not be expected to be omnicompetent across all species. In conclusion, anaesthesia undergraduate training should prioritise essential practical DOS. British Veterinary Association.

  12. Studies of Phonon Anharmonicity in Solids

    NASA Astrophysics Data System (ADS)

    Lan, Tian

    Today our understanding of the vibrational thermodynamics of materials at low temperatures is emerging nicely, based on the harmonic model in which phonons are independent. At high temperatures, however, this understanding must accommodate how phonons interact with other phonons or with other excitations. We shall see that the phonon-phonon interactions give rise to interesting coupling problems, and essentially modify the equilibrium and non-equilibrium properties of materials, e.g., thermodynamic stability, heat capacity, optical properties and thermal transport of materials. Despite its great importance, to date the anharmonic lattice dynamics is poorly understood and most studies on lattice dynamics still rely on the harmonic or quasiharmonic models. There have been very few studies on the pure phonon anharmonicity and phonon-phonon interactions. The work presented in this thesis is devoted to the development of experimental and computational methods on this subject. Modern inelastic scattering techniques with neutrons or photons are ideal for sorting out the anharmonic contribution. Analysis of the experimental data can generate vibrational spectra of the materials, i.e., their phonon densities of states or phonon dispersion relations. We obtained high quality data from laser Raman spectrometer, Fourier transform infrared spectrometer and inelastic neutron spectrometer. With accurate phonon spectra data, we obtained the energy shifts and lifetime broadenings of the interacting phonons, and the vibrational entropies of different materials. The understanding of them then relies on the development of the fundamental theories and the computational methods. We developed an efficient post-processor for analyzing the anharmonic vibrations from the molecular dynamics (MD) calculations. Currently, most first principles methods are not capable of dealing with strong anharmonicity, because the interactions of phonons are ignored at finite temperatures. Our method adopts the Fourier transformed velocity autocorrelation method to handle the big data of time-dependent atomic velocities from MD calculations, and efficiently reconstructs the phonon DOS and phonon dispersion relations. Our calculations can reproduce the phonon frequency shifts and lifetime broadenings very well at various temperatures. To understand non-harmonic interactions in a microscopic way, we have developed a numerical fitting method to analyze the decay channels of phonon-phonon interactions. Based on the quantum perturbation theory of many-body interactions, this method is used to calculate the three-phonon and four-phonon kinematics subject to the conservation of energy and momentum, taking into account the weight of phonon couplings. We can assess the strengths of phonon-phonon interactions of different channels and anharmonic orders with the calculated two-phonon DOS. This method, with high computational efficiency, is a promising direction to advance our understandings of non-harmonic lattice dynamics and thermal transport properties. These experimental techniques and theoretical methods have been successfully performed in the study of anharmonic behaviors of metal oxides, including rutile and cuprite stuctures, and will be discussed in detail in Chapters 4 to 6. For example, for rutile titanium dioxide (TiO2), we found that the anomalous anharmonic behavior of the B1g mode can be explained by the volume effects on quasiharmonic force constants, and by the explicit cubic and quartic anharmonicity. For rutile tin dioxide (SnO2), the broadening of the B2 g mode with temperature showed an unusual concave downwards curvature. This curvature was caused by a change with temperature in the number of down-conversion decay channels, originating with the wide band gap in the phonon dispersions. For silver oxide (Ag2O), strong anharmonic effects were found for both phonons and for the negative thermal expansion.

  13. Calculation of density of states for modeling photoemission using method of moments

    NASA Astrophysics Data System (ADS)

    Finkenstadt, Daniel; Lambrakos, Samuel G.; Jensen, Kevin L.; Shabaev, Andrew; Moody, Nathan A.

    2017-09-01

    Modeling photoemission using the Moments Approach (akin to Spicer's "Three Step Model") is often presumed to follow simple models for the prediction of two critical properties of photocathodes: the yield or "Quantum Efficiency" (QE), and the intrinsic spreading of the beam or "emittance" ɛnrms. The simple models, however, tend to obscure properties of electrons in materials, the understanding of which is necessary for a proper prediction of a semiconductor or metal's QE and ɛnrms. This structure is characterized by localized resonance features as well as a universal trend at high energy. Presented in this study is a prototype analysis concerning the density of states (DOS) factor D(E) for Copper in bulk to replace the simple three-dimensional form of D(E) = (m/π2 h3)p2mE currently used in the Moments approach. This analysis demonstrates that excited state spectra of atoms, molecules and solids based on density-functional theory can be adapted as useful information for practical applications, as well as providing theoretical interpretation of density-of-states structure, e.g., qualitatively good descriptions of optical transitions in matter, in addition to DFT's utility in providing the optical constants and material parameters also required in the Moments Approach.

  14. Geochemistry and petrogenesis of the Mesoarchean granites from the Canaã dos Carajás area, Carajás Province, Brazil: Implications for the origin of Archean granites

    NASA Astrophysics Data System (ADS)

    Feio, G. R. L.; Dall'Agnol, R.

    2012-12-01

    Four Mesoarchean (2.93 to 2.83 Ga) granite units, which encompass the Canaã dos Carajás, Bom Jesus, Cruzadão and Serra Dourada granites, were recognized in the Canaã dos Carajás area of the Archean Carajás Province. The Mesoarchean units are composed dominantly of biotite leucomonzogranites. They are compared with the Neoarchean Planalto suite (2.73 Ga) which encompasses biotite-hornblende monzogranites to syenogranites. The Canaã dos Carajás, Bom Jesus and the variety of the Cruzadão granite with higher (La/Yb)N are geochemically more akin to the calc-alkaline granites, whereas the other varieties of the Cruzadão granite are transitional between calc-alkaline and alkaline granites. The Serra Dourada granite has an ambiguous geochemical character with some features similar to those of calc-alkaline granites and other peraluminous granites. The Planalto granites have ferroan character, are similar geochemically to reduced A-type granites and show a strong geochemical contrast with the Mesoarchean studied granites. The Mesoarchean granites described in the Canaã dos Carajás area are geochemically distinct to those of the Rio Maria domain of the Carajás Province. The Canaã dos Carajás and Bom Jesus granites are similar to the high-Ca granites, whereas the Cruzadão and Serra Dourada are more akin to the low-CaO granites of the Yilgarn craton. The geochemical characteristics of the Mesoarchean studied granites approach those of the biotite granite group of Dharwar but the latter are enriched in HFSE and HREE compared to the Canaã dos Carajás granites. The Neoarchean Planalto suite granite has no counterpart in the Mesoarchean Rio Maria domain of the Carajás Province, neither in the Yilgarn and Dharwar cratons. Geochemical modeling suggests that partial melting of a source similar in composition to an Archean basaltic andesite of the Carajás Province could give origin to the Bom Jesus and Cruzadão granites. In the case of the Bom Jesus granite the residue of melting contained, in similar proportions, plagioclase, clinopyroxene, amphibole, and garnet, with subordinate ilmenite. The variations in (La/Yb)N and Sr/Y of the Cruzadão granite are controlled by changes in the residual melting phases. Garnet and amphibole are abundant in the residue of the variety with higher (La/Yb)N, whereas in the rocks with moderate to lower (La/Yb)N garnet is absent, magnetite appears in the residue and amphibole initially increases but is replaced by orthopyroxene in the rocks with the lowest (La/Yb)N. In the Canaã dos Carajás and Serra Dourada granites garnet was probably an absent phase in the residue of melting and the influence of amphibole was also apparently limited. A crustal environment and a variable pressure from 10 to 7-8 kbar are estimated for the generation of the granite magmas. The Bom Jesus and Cruzadão granites of Carajás derived from basaltic andesite sources and not of TTG and their geochemical contrasts can be explained by variation in the pressure of melting. The sources of Archean granite magmas are more diversified and could be more mafic than generally admitted.

  15. Products purchased from family farming for school meals in the cities of Rio Grande do Sul.

    PubMed

    Ferigollo, Daniele; Kirsten, Vanessa Ramos; Heckler, Dienifer; Figueredo, Oscar Agustín Torres; Perez-Cassarino, Julian; Triches, Rozane Márcia

    2017-02-16

    This study aims to verify the adequacy profile of the cities of the State of Rio Grande do Sul, Brazil, in relation to the purchase of products of family farming by the Programa Nacional de Alimentação Escolar (PNAE - National Program of School Meals). This is a quantitative descriptive study, with secondary data analysis (public calls-to-bid). The sample consisted of approximately 10% (n = 52) of the cities in the State, establishing a representation by mesoregion and size of the population. We have assessed the percentage of food purchased from family farming, as well as the type of product, requirements of frequency, delivery points, and presence of prices in 114 notices of public calls-to-bid, in 2013. Of the cities analyzed, 71.2% (n = 37) reached 30% of food purchased from family farming. Most public calls-to-bid demanded both products of plant (90.4%; n = 103) and animal origin (79.8%; n = 91). Regarding the degree of processing, fresh products appeared in 92.1% (n = 105) of the public calls-to-bid. In relation to the delivery of products, centralized (49.1%; n = 56) and weekly deliveries (47.4%; n = 54) were the most described. Only 60% (n = 68) of the public calls-to-bid contained the price of products. Most of the cities analyzed have fulfilled what is determined by the legislation of the PNAE. We have found in the public calls-to-bid a wide variety of food, both of plant and animal origin, and most of it is fresh. In relation to the delivery of the products, the centralized and weekly options prevailed. Verificar o perfil de adequação dos municípios do Rio Grande do Sul no que tange à aquisição de produtos da agricultura familiar pelo Programa Nacional de Alimentação Escolar. Trata-se de estudo quantitativo descritivo, com análise de dados secundários (chamadas públicas). A amostra foi composta por aproximadamente 10% (n = 52) dos municípios do estado, tomando-se o cuidado de estabelecer uma representatividade por mesorregião e tamanho da população. Foi avaliado o percentual destinado às compras de gêneros alimentícios da agricultura familiar, bem como o tipo de produto, exigências de periodicidade, pontos de entrega e presença de preços em 114 editais de chamadas públicas, no ano de 2013. Dos municípios analisados, 71,2% (n = 37) atingiram 30% de gêneros alimentícios oriundos de agricultura familiar. A maioria das chamadas públicas demandou tanto produtos de origem vegetal (90,4%; n = 103) como de origem animal (79,8%; n = 91). Quanto ao grau de processamento dos alimentos, os produtos in natura apareceram em 92,1% (n = 105) das chamadas públicas. Em relação à entrega dos produtos, a centralizada (49,1%; n = 56) e as entregas semanais (47,4%; n = 54) foram as mais descritas. Apenas 60% (n = 68) das chamadas públicas continham preço dos produtos. A maioria dos municípios analisados cumpriu o determinado pela legislação do Programa Nacional de Alimentação Escolar. Encontrou-se nas chamadas públicas uma grande diversidade de alimentos, tanto de origem vegetal quanto de origem animal, sendo a maior parte deles in natura. Em relação à entrega dos produtos, prevaleceu a centralizada e a semanal.

  16. Active corrosion protection of AA2024 by sol-gel coatings with corrosion inhibitors =

    NASA Astrophysics Data System (ADS)

    Yasakau, Kiryl

    A industria aeronautica utiliza ligas de aluminio de alta resistencia para o fabrico dos elementos estruturais dos avioes. As ligas usadas possuem excelentes propriedades mecanicas mas apresentam simultaneamente uma grande tendencia para a corrosao. Por esta razao essas ligas necessitam de proteccao anticorrosiva eficaz para poderem ser utilizadas com seguranca. Ate a data, os sistemas anticorrosivos mais eficazes para ligas de aluminio contem cromio hexavalente na sua composicao, sejam pre-tratamentos, camadas de conversao ou pigmentos anticorrosivos. O reconhecimento dos efeitos carcinogenicos do cromio hexavalente levou ao aparecimento de legislacao banindo o uso desta forma de cromio pela industria. Esta decisao trouxe a necessidade de encontrar alternativas ambientalmente inocuas mas igualmente eficazes. O principal objectivo do presente trabalho e o desenvolvimento de pretratamentos anticorrosivos activos para a liga de aluminio 2024, baseados em revestimentos hibridos produzidos pelo metodo sol-gel. Estes revestimentos deverao possuir boa aderencia ao substrato metalico, boas propriedades barreira e capacidade anticorrosiva activa. A proteccao activa pode ser alcancada atraves da incorporacao de inibidores anticorrosivos no pretratamento. O objectivo foi atingido atraves de uma sucessao de etapas. Primeiro investigou-se em detalhe a corrosao localizada (por picada) da liga de aluminio 2024. Os resultados obtidos permitiram uma melhor compreensao da susceptibilidade desta liga a processos de corrosao localizada. Estudaram-se tambem varios possiveis inibidores de corrosao usando tecnicas electroquimicas e microestruturais. Numa segunda etapa desenvolveram-se revestimentos anticorrosivos hibridos organico-inorganico baseados no metodo sol-gel. Compostos derivados de titania e zirconia foram combinados com siloxanos organofuncionais a fim de obter-se boa aderencia entre o revestimento e o substrato metalico assim como boas propriedades barreira. Testes industriais mostraram que estes novos revestimentos sao compativeis com os esquemas de pintura convencionais actualmente em uso. A estabilidade e o prazo de validade das formulacoes foram optimizados modificando a temperatura de armazenamento e a quantidade de agua usada durante a sintese. As formulacoes sol-gel foram dopadas com os inibidores seleccionados durante a primeira etapa e as propriedades anticorrosivas passivas e activas dos revestimentos obtidos foram estudadas numa terceira etapa do trabalho. Os resultados comprovam a influencia dos inibidores nas propriedades anticorrosivas dos revestimentos sol-gel. Em alguns casos a accao activa dos inibidores combinou-se com a proteccao passiva dada pelo revestimento mas noutros casos tera ocorrido interaccao quimica entre o inibidor e a matriz de sol-gel, de onde resultou a perda de propriedades protectoras do sistema combinado. Atendendo aos problemas provocados pela adicao directa dos inibidores na formulacao sol-gel procurou-se, numa quarta etapa, formas alternativas de incorporacao. Na primeira, produziu-se uma camada de titania nanoporosa na superficie da liga metalica que serviu de reservatorio para os inibidores. O revestimento sol-gel foi aplicado por cima da camada nanoporosa. Os inibidores armazenados nos poros actuam quando o substrato fica exposto ao ambiente agressivo. Numa segunda, os inibidores foram armazenados em nano-reservatorios de silica ou em nanoargilas (halloysite), os quais foram revestidos por polielectrolitos montados camada a camada. A terceira alternativa consistiu no uso de nano-fios de molibdato de cerio amorfo como inibidores anticorrosivos nanoparticulados. Os nano-reservatorios foram incorporados durante a sintese do sol-gel. Qualquer das abordagens permitiu eliminar o efeito negativo do inibidor sobre a estabilidade da matriz do sol-gel. Os revestimentos sol-gel desenvolvidos neste trabalho apresentaram proteccao anticorrosiva activa e capacidade de auto-reparacao. Os resultados obtidos mostraram o elevado potencial destes revestimentos para a proteccao anticorrosiva da liga de aluminio 2024.

  17. Uma Visão do Universo Segundo um Grupo de Alunos do Ensino Médio de São Paulo

    NASA Astrophysics Data System (ADS)

    Elias, D. S.; Araújo, M.; Amaral, L. H.; Voelzke, M. R.; Araújo, M.

    2005-08-01

    A astronomia, embora seja uma ciência popular, com inúmeras descobertas de interesse público, ainda é apresentada desconsiderando-se os aspectos históricos e científicos relacionados ao seu desenvolvimento, sendo geralmente veiculada nos meios de comunicação de maneira pouco esclarecedora e não raro com imprecisões. Neste trabalho analisou-se a concepção de um grupo de estudantes de Ensino Médio sobre conceitos de astronomia, visando identificar sua visão de mundo a respeito do Universo, envolvendo idéias sobre espaço e tempo. Para issso, foi aplicado um questionário em três escolas da grande São Paulo em um espaço amostral de 270 alunos. Constatou-se que, embora o ensino de astronomia esteja previsto nos PCNEM, os resultados obtidos na pesquisa mostram que há grande deficiência no conhecimento dos temas investigados. Nesse sentido, verificou-se que apenas 20% dos alunos eram capazes de relacionar a sucessão das semanas com as fases da lua, enquanto 28% associaram as estações do ano à inclinação do eixo de rotação da Terra. Por outro lado, somente 23% dos alunos tinham noções das distâncias entre os objetos celestes próximos da Terra e 56% conseguiram relacionar o Big Bang com a origem do Universo. Finalmente, constatou-se que 37% reconheciam o ano-luz como uma unidade de distância e 60% reconheciam o Sol como sendo uma estrela. Apesar de 60% dos alunos indicarem que a escola é a principal fonte para aquisição dos conhecimentos de astronomia, conclui-se que seus conceitos nessa área ainda são inadequados, havendo necessidade de ampliação e aprimoramento da abordagem desses conteúdos nos ambientes escolares.

  18. Experiências internacionais da aplicação de sistemas de apoio à decisão clínica em gastroenterologia

    PubMed Central

    Tenório, Josceli Maria; Hummel, Anderson Diniz; Sdepanian, Vera Lucia; Pisa, Ivan Torres; de Fátima Marin, Heimar

    2015-01-01

    Objetivo Descrever as experiências recentes com a aplicação de sistemas de apoio à decisão clínica em gastroenterologia, de forma a estabelecer o nível de desenvolvimento, testes e vantagens conferidas à prática médica com a introdução desses softwares. Métodos Foi realizada busca nas bases de dados PubMed, LILACS e ISI Web of Knowledge, utilizando termos relacionados à sistemas de apoio à decisão e à gastroenterogia, incluindo artigos originais publicados no período entre 2005 e 2010. Foram recuperadas 104 publicações, na busca inicial e, após a aplicação dos critérios de inclusão e exclusão, foram eleitos nove estudos para leitura do texto completo. Resultados Os sistemas de apoio à decisão clínica apresentam grande multiplicidade de problemas clínicos e investigação de doenças. Em 89% dos casos, são descritos modelos experimentais para o desenvolvimento de sistemas de apoio à decisão clínica. A descrição dos resultados obtidos por técnicas de inteligência artificial em 78% das publicações. Em dois dos estudos foram realizadas comparações com o médico e em apenas uma publicação um estudo controlado foi descrito, mostrando evidências de melhorias na prática médica. Conclusão Os estudos mostram potenciais benefícios dos sistemas de apoio à decisão clínica à prática médica, porém, estudos controlados em ambiente real devem ser realizados para comprovar esta perspectiva. PMID:26491625

  19. Shedding Synchrotron Light on a Puzzle of Glasses

    ScienceCinema

    Chumakov, Aleksandr [European Synchrotron Radiation Facility, Grenoble, France

    2017-12-09

    Vibrational dynamics of glasses remains a point of controversial discussions. In particular, the density of vibrational states (DOS) reveals an excess of states above the Debye model called "boson peak." Despite the fact that this universal feature for all glasses has been known for more than 35 years, the nature of the boson peak is still not understood. The application of nuclear inelastic scattering via synchrotron radiation perhaps provides a clearer, more consistent picture of the subject. The distinguishing features of nuclear inelastic scattering relative to, e.g., neutron inelastic scattering, are ideal momentum integration and exact scaling of the DOS in absolute units. This allows for reliable comparison to data from other techniques such as Brillouin light scattering. Another strong point is ideal isotope selectivity: the DOS is measured for a single isotope with a specific low-energy nuclear transition. This allows for special "design" of an experiment to study, for instance, the dynamics of only center-of-mass motions. Recently, we have investigated the transformation of the DOS as a function of several key parameters such as temperature, cooling rate, and density. In all cases the transformation of the DOS is sufficiently well described by a transformation of the continuous medium, in particular, by changes of the macroscopic density and the sound velocity. These results suggest a collective sound-like nature of vibrational dynamics in glasses and cast doubts on microscopic models of glass dynamics. Further insight can be obtained in combined studies of glass with nuclear inelastic and inelastic neutron scattering. Applying two techniques, we have measured the energy dependence of the characteristic correlation length of atomic motions. The data do not reveal localization of atomic vibrations at the energy of the boson peak. Once again, the results suggest that special features of glass dynamics are related to extended motions and not to local models.

  20. Instruments used in the assessment of expectation toward a spine surgery: an integrative review.

    PubMed

    Nepomuceno, Eliane; Silveira, Renata Cristina de Campos Pereira; Dessotte, Carina Aparecida Marosti; Furuya, Rejane Kiyomi; Arantes, Eliana De Cássia; Cunha, Débora Cristine Prévide Teixeira da; Dantas, Rosana Aparecida Spadoti

    2016-01-01

    To identify and describe the instruments used to assess patients' expectations toward spine surgery. An integrative review was carried out in the databases PubMed, CINAHL, LILACS and PsycINFO. A total of 4,402 publications were identified, of which 25 met the selection criteria. Of the studies selected, only three used tools that had confirmed validity and reliability to be applied; in five studies, clinical scores were used, and were modified for the assessment of patients' expectations, and in 17 studies the researchers developed scales without an adequate description of the method used for their development and validation. The assessment of patients' expectations has been methodologically conducted in different ways. Until the completion of this integrative review, only two valid and reliable instruments had been used in three of the selected studies. Identificar e descrever os instrumentos usados para avaliar a expectativa dos pacientes diante do tratamento cirúrgico da coluna vertebral. Revisão Integrativa realizada nas bases de dados PubMed, CINAHL, LILACS e PsycINFO. Identificamos 4.402 publicações, das quais 25 atenderam aos critérios de seleção. Dos estudos selecionados, apenas em três os autores utilizaram instrumentos que possuíam validade e confiabilidade confirmadas para serem aplicados; em cinco estudos foram utilizados escores clínicos, modificados para a avaliação das expectativas dos pacientes, e em dezessete os pesquisadores elaboraram escalas sem adequada descrição do método usado para o seu desenvolvimento e validação. A avaliação das expectativas dos pacientes tem sido metodologicamente conduzida de diferentes maneiras. Até a finalização desta revisão integrativa, apenas dois instrumentos, válidos e confiáveis, haviam sido utilizados em três dos estudos selecionados.

  1. The effects of dust on Colorado mountain snow cover albedo and compositional links to dust-source areas

    NASA Astrophysics Data System (ADS)

    Goldstein, H. L.; Reynolds, R. L.; Landry, C.; Derry, J. E.; Kokaly, R. F.; Breit, G. N.

    2016-12-01

    Dust deposited on mountain snow cover (DOS) changes snow albedo, enhances absorption of solar radiation, and effectively increases rates of snow melt, leading to earlier-than-normal runoff and overall smaller late-season water supplies for tens of millions of people and industries in the American West. Visible-spectrum reflectance of DOS samples is on the order of 0.2 (80% absorption), in stark contrast to the high reflectivity of pure snow which approaches 1.0. Samples of DOS were collected from 12 high-elevation Colorado mountain sites near the end of spring from 2013 through 2016 prior to complete snow melt, when most dust layers had merged into one layer. These samples were analyzed to measure dust properties that affect snow albedo and to link DOS to dust-source areas. Dust mass loadings to snow during water year 2014 varied from 5 to 30 g/m2. Median particle sizes centered around 20 micrometers with more than 80% of the dust <63 micrometers. Dark minerals, carbonaceous matter, and iron oxides, including nano-sized hematite and goethite, together diminished reflectance according to their variable concentrations. Documenting variations in dust-particle masses, sizes, and compositions helps determine their influences on snow-melt and may be useful for modeling snow-melt effects from future dust. Furthermore, variations in dust components and particle sizes lead to new ways to recognize sources of dust by comparison with properties of fine-grained sediments in dust-source areas. Much of the DOS in the San Juan Mountains, Colorado can be linked to southern Colorado Plateau source areas by compositional similarities and satellite imagery. Understanding dust properties that affect snow albedo and recognizing the sources of dust deposited on snow cover may guide mitigation of dust emission that affects water resources of the Colorado River basin.

  2. Diversity-Oriented Synthesis as a Strategy for Fragment Evolution against GSK3β

    PubMed Central

    2016-01-01

    Traditional fragment-based drug discovery (FBDD) relies heavily on structural analysis of the hits bound to their targets. Herein, we present a complementary approach based on diversity-oriented synthesis (DOS). A DOS-based fragment collection was able to produce initial hit compounds against the target GSK3β, allow the systematic synthesis of related fragment analogues to explore fragment-level structure–activity relationship, and finally lead to the synthesis of a more potent compound. PMID:27660690

  3. Provincial Reconstruction Teams: Developing a Cost-Tracking Process will Enhance Decision-Making

    DTIC Science & Technology

    2009-04-28

    calculated on a per person basis these contractors account for approximately $9 million of the $30 7 While DoD captures costs in other areas, it...DoS Can Track PRT Costs Although U.S. government accounting standards require agencies to track program costs , according to officials, DoS and DoD...DoS’ global accounting and payroll systems have the capability to track total or individual PRT costs , according to DoS officials. In April 2008

  4. Spread spectrum time-resolved diffuse optical measurement system for enhanced sensitivity in detecting human brain activity

    NASA Astrophysics Data System (ADS)

    Mehta, Kalpesh; Hasnain, Ali; Zhou, Xiaowei; Luo, Jianwen; Penney, Trevor B.; Chen, Nanguang

    2017-04-01

    Diffuse optical spectroscopy (DOS) and imaging methods have been widely applied to noninvasive detection of brain activity. We have designed and implemented a low cost, portable, real-time one-channel time-resolved DOS system for neuroscience studies. Phantom experiments were carried out to test the performance of the system. We further conducted preliminary human experiments and demonstrated that enhanced sensitivity in detecting neural activity in the cortex could be achieved by the use of late arriving photons.

  5. Mission Networks: An Evolution in Information Sharing

    DTIC Science & Technology

    2012-03-20

    Publication 6-0 Joint Communications System states that the Global Information Grid ( GIG ) composed of the Defense Information Systems Network (DISN...of the GIG while the other branches of the United States Government (USG) such as the Department of State (DoS) utilize the ’.gov’ sub-network of...the GIG . The result is that unless the DOD has a ’need to know’ it will never have access to the DOS information that resides on the ’.gov’ sub-network

  6. Quantification of joint inflammation in rheumatoid arthritis by time-resolved diffuse optical spectroscopy and tracer kinetic modeling

    NASA Astrophysics Data System (ADS)

    Ioussoufovitch, Seva; Morrison, Laura B.; Lee, Ting-Yim; St. Lawrence, Keith; Diop, Mamadou

    2015-03-01

    Rheumatoid arthritis (RA) is characterized by chronic synovial inflammation, which can cause progressive joint damage and disability. Diffuse optical spectroscopy (DOS) and imaging have the potential to become potent monitoring tools for RA. We devised a method that combined time-resolved DOS and tracer kinetics modeling to rapidly and reliably quantify blood flow in the joint. Preliminary results obtained from two animals show that the technique can detect joint inflammation as early as 5 days after onset.

  7. Creation of Novel Solid-Solution Alloy Nanoparticles on the Basis of Density-of-States Engineering by Interelement Fusion.

    PubMed

    Kobayashi, Hirokazu; Kusada, Kohei; Kitagawa, Hiroshi

    2015-06-16

    Currently 118 known elements are represented in the periodic table. Of these 118 elements, only about 80 elements are stable, nonradioactive, and widely available for our society. From the viewpoint of the "elements strategy", we need to make full use of the 80 elements to bring out their latent ability and create innovative materials. Furthermore, there is a strong demand that the use of rare or toxic elements be reduced or replaced while their important properties are retained. Advanced science and technology could create higher-performance materials even while replacing or reducing minor or harmful elements through the combination of more abundant elements. The properties of elements are correlated directly with their electronic states. In a solid, the magnitude of the density of states (DOS) at the Fermi level affects the physical and chemical properties. In the present age, more attention has been paid to improving the properties of materials by means of alloying elements. In particular, the solid-solution-type alloy is advantageous because the properties can be continuously controlled by tuning the compositions and/or combinations of the constituent elements. However, the majority of bulk alloys are of the phase-separated type under ambient conditions, where constituent elements are immiscible with each other. To overcome the challenge of the bulk-phase metallurgical aspects, we have focused on the nanosize effect and developed methods involving "nonequilibrium synthesis" or "a process of hydrogen absorption/desorption". We propose a new concept of "density-of-states engineering" for the design of materials having the most desirable and suitable properties by means of "interelement fusion". In this Account, we describe novel solid-solution alloys of Pd-Pt, Ag-Rh, and Pd-Ru systems in which the constituent elements are immiscible in the bulk state. The homogeneous solid-solution alloys of Pd and Pt were created from Pd core/Pt shell nanoparticles using a hydrogen absorption/desorption process as a trigger. Several atom percent replacements of Pd with Pt atoms resulted in a significantly enhanced hydrogen absorption capacity compared with Pd nanoparticles. AgxRh1-x and PdxRu1-x solid-solution alloy nanoparticles were also developed by nonequilibrium synthesis based on a polyol method. The AgxRh1-x nanoparticles demonstrated hydrogen storage properties, although pure metal nanoparticles of each constituent element do not adsorb hydrogen. AgxRh1-x is therefore considered to possess a similar electronic structure to Pd as a synthetic pseudo-palladium. The PdxRu1-x nanoparticles showed enhanced catalytic activity for CO oxidation, with the highest catalytic activity found using the equimolar Pd0.5Ru0.5 nanoparticles. The catalytic activity of the Pd0.5Ru0.5 nanoparticles exceeds that of the widely used and best-performing Ru catalysts for CO oxidation and is also higher than that of neighboring Rh on the periodic table. Our present work provides a guiding principle for the design of a suitable DOS shape according to the intended physical and/or chemical properties and a method for the development of novel solid-solution alloys.

  8. DATASPACE - A PROGRAM FOR THE LOGARITHMIC INTERPOLATION OF TEST DATA

    NASA Technical Reports Server (NTRS)

    Ledbetter, F. E.

    1994-01-01

    Scientists and engineers work with the reduction, analysis, and manipulation of data. In many instances, the recorded data must meet certain requirements before standard numerical techniques may be used to interpret it. For example, the analysis of a linear visoelastic material requires knowledge of one of two time-dependent properties, the stress relaxation modulus E(t) or the creep compliance D(t), one of which may be derived from the other by a numerical method if the recorded data points are evenly spaced or increasingly spaced with respect to the time coordinate. The problem is that most laboratory data are variably spaced, making the use of numerical techniques difficult. To ease this difficulty in the case of stress relaxation data analysis, NASA scientists developed DATASPACE (A Program for the Logarithmic Interpolation of Test Data), to establish a logarithmically increasing time interval in the relaxation data. The program is generally applicable to any situation in which a data set needs increasingly spaced abscissa values. DATASPACE first takes the logarithm of the abscissa values, then uses a cubic spline interpolation routine (which minimizes interpolation error) to create an evenly spaced array from the log values. This array is returned from the log abscissa domain to the abscissa domain and written to an output file for further manipulation. As a result of the interpolation in the log abscissa domain, the data is increasingly spaced. In the case of stress relaxation data, the array is closely spaced at short times and widely spaced at long times, thus avoiding the distortion inherent in evenly spaced time coordinates. The interpolation routine gives results which compare favorably with the recorded data. The experimental data curve is retained and the interpolated points reflect the desired spacing. DATASPACE is written in FORTRAN 77 for IBM PC compatibles with a math co-processor running MS-DOS and Apple Macintosh computers running MacOS. With minor modifications the source code is portable to any platform that supports an ANSI FORTRAN 77 compiler. MicroSoft FORTRAN v2.1 is required for the Macintosh version. An executable is included with the PC version. DATASPACE is available on a 5.25 inch 360K MS-DOS format diskette (standard distribution) or on a 3.5 inch 800K Macintosh format diskette. This program was developed in 1991. IBM PC is a trademark of International Business Machines Corporation. MS-DOS is a registered trademark of Microsoft Corporation. Macintosh and MacOS are trademarks of Apple Computer, Inc.

  9. Lanthanide oxide and phosphate nanoparticles for thermometry and bimodal imaging =

    NASA Astrophysics Data System (ADS)

    Debasu, Mengistie Leweyehu

    Nesta tese relatam-se estudos de fotoluminescencia de nanoparticulas de oxidos e fosfatos dopados com ioes trivalentes de lantanideos, respectivamente, nanobastonetes de (Gd,Eu)2O3 e (Gd,Yb,Er)2O3 e nanocristais de (Gd,Yb,Tb)PO4, demonstrando-se tambem aplicacoes destes materiais em revestimentos inteligentes, sensores de temperatura e bioimagem. Estuda-se a transferencia de energia entre os sitios de Eu3+ C2 e S6 dos nanobastonetes Gd2O3. A contribuicao dos mecanismos de transferencia de energia entre sitios para o tempo de subida 5D0(C2) e descartada a favor da relaxacao directa 5D1(C2) 5D0(C2) (i.e., transferencia de energia entre niveis). O maior tempo de decaimento do nivel 5D0(C2) nos nanobastonetes, relativamente ao valor medido para o mesmo material na forma de microcristais, e atribuido, quer a existencia de espacos livres entre nanobastonetes proximos (factor de enchimento ou fraccao volumica), quer a variacao do indice de refraccao efectivo do meio em torno dos ioes Eu3+. A dispersao de nanobastonetes de (Gd,Eu)2O3 em tres resinas epoxi comerciais atraves da cura por UV permite obter nanocompositos epoxi- (Gd,Eu)2O3. Relatam-se estudos cineticos e das propriedades termicas e de fotoluminescencia destes nanocompositos. Estes, preservam as tipicas propriedades de emissao do Eu3+, mostrando o potencial do metodo de cura por UV para obter revistimentos inteligentes e fotoactivos. Considera-se um avanco significativo a realizacao de uma nanoplataforma optica, incorporando aquecedor e termometro e capaz de medir uma ampla gama de temperaturas (300-2000 K) a escala nano, baseada em nanobastonetes de (Gd,Yb,Er)2O3 (termometros) cuja superficie se encontra revestida com nanoparticulas de ouro. A temperature local e calculada usando, quer a distribuicao de Boltzmann (300-1050 K) do racio de intensidades da conversao ascendente 2H11=2!4I15=2/4S3=2!4I15=2, quer a lei de Planck (1200-2000 K) para uma emissao de luz branca atribuida a radiacao do corpo negro. Finalmente, estudam-se as propriedades de fotoluminescencia correspondentes as conversoes ascendente e descendente de energia em nanocristais de (Gd,Yb,Tb)PO4 sintetizados por via hidrotermica. A relaxividade (ressonancia magnetica) do 1H destes materiais sao investigadas, tendo em vista possiveis aplicacoes em imagem bimodal (luminescencia e ressonancia magnetica nuclear).

  10. Nurses in post-operative heart surgery: professional competencies and organization strategies.

    PubMed

    Santos, Ana Paula Azevedo; Camelo, Silvia Helena Henriques; Santos, Fabiana Cristina Dos; Leal, Laura Andrian; Silva, Beatriz Regina da

    2016-01-01

    To analyze nurses' competencies with regard to their work in post-operative heart surgery and the strategies implemented to mobilize these competencies. This was an exploratory study with a qualitative approach and a methodological design of collective case study. It was carried out in three post-operative heart surgery units, consisting of 18 nurses. Direct observation and semi-structured interviews were employed to collect data. Data were construed through thematic analysis. nine competencies were found, as follows: theoretical-practical knowledge; high-complexity nursing care; nursing supervision; leadership in nursing; decision making; conflict management; personnel management; material and financial resources management; and on-job continued education. Organizational and individual strategies were employed to develop and improve competencies such as regular offerings of courses and lectures, in addition to the individual pursuit for knowledge and improvement. the study is expected to lead future nurses and training centers to evaluate the need for furthur training required to work in cardiac units, and also the need for implementing programs aimed at developing the competencies of these professionals. Analisar as competências dos enfermeiros para atuarem no pós-operatório de cirurgia cardíaca e estratégias implementadas para a mobilização dessas competências. Estudo exploratório, com abordagem qualitativa e desenho metodológico estudo de caso coletivo. Foi realizado em três unidades pós-operatórias de cirurgias cardíacas, com 18 enfermeiros. Na coleta de dados utilizou-se observação direta e entrevista semiestruturada. Para interpretação dos dados optou-se pela análise temática. Foram identificadas nove competências, sendo: conhecimento teórico-prático, cuidados de enfermagem de alta complexidade, supervisão e liderança em enfermagem, tomada de decisão, gerenciamento de conflitos, de recursos humanos, materiais, financeiros e educação continuada em serviço. Estratégias organizacionais e individuais são realizadas a fim de desenvolver e aprimorar competências, tais como: oferecimento de cursos e palestras periodicamente, além da busca individual por conhecimento e aperfeiçoamento. O estudo deve provocar a reflexão de futuros enfermeiros e dos centros formadores quanto à formação necessária para atuar em unidades cardíacas e sobre a necessidade de implementação de programas que visam desenvolver competências nestes profissionais.

  11. Etched distributed Bragg reflectors as three-dimensional photonic crystals: photonic bands and density of states.

    PubMed

    Pavarini, E; Andreani, L C

    2002-09-01

    The photonic band dispersion and density of states (DOS) are calculated for the three-dimensional (3D) hexagonal structure corresponding to a distributed Bragg reflector patterned with a 2D triangular lattice of circular holes. Results for the Si/SiO(2) and GaAs/Al(x)Ga(1-x)As systems determine the optimal parameters for which a gap in the 2D plane occurs and overlaps the 1D gap of the multilayer. The DOS is considerably reduced in correspondence with the overlap of 2D and 1D gaps. Also, the local density of states (i.e., the DOS weighted with the squared electric field at a given point) has strong variations depending on the position. Both results imply substantial changes of spontaneous emission rates and patterns for a local emitter embedded in the structure and make this system attractive for the fabrication of a 3D photonic crystal with controlled radiative properties.

  12. Bandstructure modulation for Si-h and Si-g nanotubes in a transverse electric field: Tight binding approach

    NASA Astrophysics Data System (ADS)

    Chegel, Raad; Behzad, Somayeh

    2013-11-01

    We have investigated the electronic properties of SiNTs, under the external electric field, using Tight Binding (TB) approximation. It was found that the energy levels, energy gaps, and density of states (DOS) strongly depend on the electric field strength. The large electric strength leads to coupling the neighbor subbands and induce destruction of subband degeneracy, increase of low-energy states, and strong modulation of energy gap which these effects reflect in the DOS spectrum. It has been shown that, the band gap reduction of Si g-NTs is linearly proportional to the electric field strength. The band gap variation for Si h-NTs increases first and later decreases (Metallic) or first remains constant and then decreases (semiconductor). Also we show that the larger diameter tubes are more sensitive to the field strength than smaller ones. The semiconducting metallic transition or vice versa can be achieved through an increasing of applied fields. Number and position of peaks in DOS spectrum are dependent on electric field strength.

  13. Epi info - present and future.

    PubMed

    Su, Y; Yoon, S S

    2003-01-01

    Epi Info is a suite of public domain computer programs for public health professionals developed by the Centers for Disease Control and Prevention (CDC). Epi Info is used for rapid questionnaire design, data entry and validation, data analysis including mapping and graphing, and creation of reports. Epi Info was originally created in 1985 using Turbo Pascal. In 1998, the last version of Epi Info for DOS, version 6, was released. Epi Info for DOS is currently supported by CDC but is no longer updated. The current version, Epi Info 2002, is Windows-based software developed using Microsoft Visual Basic. Approximately 300,000 downloads of Epi Info software occurred in 2002 from approximately 130 countries. These numbers make Epi Info probably one of the most widely distributed and used public domain programs in the world. The DOS version of Epi Info was translated into 13 languages, and efforts are underway to translate the Windows version into other major languages. Versions already exist for Spanish, French, Portuguese, Chinese, Japanese, and Arabic.

  14. A DFT study of ethanol adsorption and decomposition on α-Al2O3(0 0 0 1) surface

    NASA Astrophysics Data System (ADS)

    Chiang, Hsin-Ni; Nachimuthu, Santhanamoorthi; Cheng, Ya-Chin; Damayanti, Nur Pradani; Jiang, Jyh-Chiang

    2016-02-01

    Ethanol adsorption and decomposition on the clean α-Al2O3(0 0 0 1) surface have been systematically investigated by density functional theory calculations. The nature of the surface-ethanol bonding has studied through the density of states (DOS) and the electron density difference (EDD) contour plots. The DOS patterns confirm that the lone pair electrons of EtOH are involved in the formation of a surface Alsbnd O dative bond and the EDD plots provide evidences for the bond weakening/forming, which are consistent with the DOS analysis. Our ethanol decomposition results indicate that ethanol dehydration to ethylene (CH3CH2OH(a) → C2H4(g) + OH(a) + H(a)), is the main reaction pathway with the energy barrier of 1.46 eV. Although the cleavage of the hydroxyl group of ethanol has lower energy barrier, the further decomposition of ethoxy owns much higher energy barrier.

  15. RighTime: A real time clock correcting program for MS-DOS-based computer systems

    NASA Technical Reports Server (NTRS)

    Becker, G. Thomas

    1993-01-01

    A computer program is described which effectively eliminates the misgivings of the DOS system clock in PC/AT-class computers. RighTime is a small, sophisticated memory-resident program that automatically corrects both the DOS system clock and the hardware 'CMOS' real time clock (RTC) in real time. RighTime learns what corrections are required without operator interaction beyond the occasional accurate time set. Both warm (power on) and cool (power off) errors are corrected, usually yielding better than one part per million accuracy in the typical desktop computer with no additional hardware, and RighTime increases the system clock resolution from approximately 0.0549 second to 0.01 second. Program tools are also available which allow visualization of RighTime's actions, verification of its performance, display of its history log, and which provide data for graphing of the system clock behavior. The program has found application in a wide variety of industries, including astronomy, satellite tracking, communications, broadcasting, transportation, public utilities, manufacturing, medicine, and the military.

  16. DEZ ANOS DE EXPERIÊNCIA DO COMITÊ DE ÉTICA EM PESQUISA DA SECRETARIA DE SAÚDE DO DISTRITO FEDERAL, BRASIL

    PubMed Central

    Novaes, Maria Rita C. G.; Guilhem, Dirce; Lolas, Fernando

    2009-01-01

    O objetivo deste artigo é relatar a experiência do Comitê de Ética em Pesquisa da Secretaria de Estado de Saúde do Distrito Federal (CEP/SES/DF) Brasil, durante o período de 10 anos a partir de sua fundação. Trata-se de uma avaliação descritiva e documental, na modalidade estudo de caso, utilizando-se a totalidade de projetos protocolados no CEP/SES/DF (N° 052/08) nesse período. As pendências mais freqüentes dos projetos foram: termo de consentimento livre e esclarecido (30%), folha de rosto (25%), metodologia (20%), curriculum vitae (12%), planilha de orçamento (9%), outros (4%). O relato das atividades do CEP/SES/DF no período de 10 anos revelou, através de sua produtividade, a legitimidade do processo de análise ética dos protocolos visando à proteção dos participantes da pesquisa. PMID:19888441

  17. Nonequilibrium Kondo effect in a magnetic field: auxiliary master equation approach

    NASA Astrophysics Data System (ADS)

    Fugger, Delia M.; Dorda, Antonius; Schwarz, Frauke; von Delft, Jan; Arrigoni, Enrico

    2018-01-01

    We study the single-impurity Anderson model out of equilibrium under the influence of a bias voltage ϕ and a magnetic field B. We investigate the interplay between the shift ({ω }B) of the Kondo peak in the spin-resolved density of states (DOS) and the one ({φ }B) of the conductance anomaly. In agreement with experiments and previous theoretical calculations we find that, while the latter displays a rather linear behavior with an almost constant slope as a function of B down to the Kondo scale, the DOS shift first features a slower increase reaching the same behavior as {φ }B only for | g| {μ }BB\\gg {k}B{T}K. Our auxiliary master equation approach yields highly accurate nonequilibrium results for the DOS and for the conductance all the way from within the Kondo up to the charge fluctuation regime, showing excellent agreement with a recently introduced scheme based on a combination of numerical renormalization group with time-dependent density matrix renormalization group.

  18. Geochemistry and genesis of the angrites

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, David W.; Lindstrom, Marilyn M.

    1990-01-01

    The major and trace elements were analyzed in samples of LEW86010, LEW87051, and Angra dos Reis angrites were analyzed using INAA and fused-bead EMP techniques. Results suggest that all three angrites originated on a volatile-depleted (Na-poor) but oxidized parent body or on several bodies. The combination of low Na and high FeO/MnO found in these samples suggests that the extreme Na depletion was caused by parent-body outgassing during differentiation, rather than by nebular processes. It was also found that the refractory-element abundances observed in LEW86010 and LEW87051 are related via olivine control; it is suggested that LEW86010 may be a residual melt from a LEW87051-like precursor or that LEW87051 formed from a LEW86010-like precursor via olivine accumulation. On the other hand, the Angra dos Reis displayed an unusual refractory element pattern suggesting that either the angrite parent body was heterogeneous or that Angra dos Reis was formed on a parent body different from that of the other two angrites.

  19. Driving Task: How Older Drivers' On-Road Driving Performance Relates to Abilities, Perceptions, and Restrictions.

    PubMed

    Koppel, Sjaan; Charlton, Judith L; Langford, Jim; Di Stefano, Marilyn; MacDonald, Wendy; Vlahodimitrakou, Zafiroula; Mazer, Barbara L; Gelinas, Isabelle; Vrkljan, Brenda; Eliasz, Kinga; Myers, Anita; Tuokko, Holly A; Marshall, Shawn C

    2016-06-01

    This study examined a cohort of 227 older drivers and investigated the relationship between performance on the electronic Driver Observation Schedule (eDOS) driving task and: (1) driver characteristics; (2) functional abilities; (3) perceptions of driving comfort and abilities; and (4) self-reported driving restrictions. Participants (male: 70%; age: M = 81.53 years, SD = 3.37 years) completed a series of functional ability measures and scales on perceived driving comfort, abilities, and driving restrictions from the Year 2 Candrive/Ozcandrive assessment protocol, along with an eDOS driving task. Observations of participants' driving behaviours during the driving task were recorded for intersection negotiation, lane-changing, merging, low-speed maneuvers, and maneuver-free driving. eDOS driving task scores were high (M = 94.74; SD = 5.70) and significantly related to participants' perceived driving abilities, reported frequency of driving in challenging situations, and number of driving restrictions. Future analyses will explore potential changes in driving task scores over time.

  20. Structure of V{sub 2}AlC studied by theory and experiment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schneider, Jochen M.; Mertens, Raphael; Music, Denis

    2006-01-01

    We have studied V{sub 2}AlC (space group P6{sub 3}/mmc, prototype Cr{sub 2}AlC) by ab initio calculations. The density of states (DOS) of V{sub 2}AlC for antiferromagnetic, ferromagnetic, and paramagnetic configurations have been discussed. According to the analysis of DOS and cohesive energy, no significant stability differences between spin-polarized and non-spin-polarized configurations were found. Based on the partial DOS analysis, V{sub 2}AlC can be classified as a strongly coupled nanolaminate according to our previous work [Z. Sun, D. Music, R. Ahuja, S. Li, and J. M. Schneider, Phys. Rev. B 70, 092102 (2004)]. Furthermore, this phase has been synthesized in themore » form of thin films by magnetron sputtering. The equilibrium volume, determined by x-ray diffraction, is in good agreement with the theoretical data, implying that ab initio calculations provide an accurate description of V{sub 2}AlC.« less

  1. A novel spiroindoline targets cell cycle and migration via modulation of microtubule cytoskeleton.

    PubMed

    Kumar, Naveen; Hati, Santanu; Munshi, Parthapratim; Sen, Subhabrata; Sehrawat, Seema; Singh, Shailja

    2017-05-01

    Natural product-inspired libraries of molecules with diverse architectures have evolved as one of the most useful tools for discovering lead molecules for drug discovery. In comparison to conventional combinatorial libraries, these molecules have been inferred to perform better in phenotypic screening against complicated targets. Diversity-oriented synthesis (DOS) is a forward directional strategy to access such multifaceted library of molecules. From a successful DOS campaign of a natural product-inspired library, recently a small molecule with spiroindoline motif was identified as a potent anti-breast cancer compound. Herein we report the subcellular studies performed for this molecule on breast cancer cells. Our investigation revealed that it repositions microtubule cytoskeleton and displaces AKAP9 located at the microtubule organization centre. DNA ladder assay and cell cycle experiments further established the molecule as an apoptotic agent. This work further substantiated the amalgamation of DOS-phenotypic screening-sub-cellular studies as a consolidated blueprint for the discovery of potential pharmaceutical drug candidates.

  2. Influence of nitrogen doping in sumanene framework toward hydrogen storage: A computational study.

    PubMed

    Reisi-Vanani, Adel; Shamsali, Fatemeh

    2017-09-01

    Two conditions are important to obtain appropriate substances for hydrogen storage; high surface area and fitting binding energy (BE). Doping is a key strategy that improves BE. We investigated hydrogen adsorption onto twenty six nitrogen disubstituted isomers of sumanene (C 19 N 2 H 12 ) by MP2/6-311++G(d,p)//B3LYP/6-31+G(d) and M06-2X/6-31+G(d) levels of theory. Effect of nitrogen doping in different positions of sumanene was checked. To obtain better BE, basis set superposition error (BSSE) and zero point energy (ZPE) corrections were used. Anticipating of adsorption sites and extra details about adsorption process was done by molecular electrostatic potential (MEP) surfaces. Various types of density of state (DOS) diagrams such as total DOS (TDOS), projected DOS (PDOS) and overlap population DOS (OPDOS) and natural bond orbital (NBO) analysis were used to find better insight on the adsorption properties. In addition of temperature depending of the BE, HOMO-LUMO gap (HLG), dipole moment, reactivity and stability, bowl depth and natural population analysis (NPA) of the isomers were studied. A physisorption mechanism for adsorption was proposed and a trivial change was seen. Place of nitrogen atoms in sumanene frame causes to binding energy increases or decreases compared with pristine sumanene. The best and the worst isomers and category of isomers were suggested. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. A 3D visualization and guidance system for handheld optical imaging devices

    NASA Astrophysics Data System (ADS)

    Azar, Fred S.; de Roquemaurel, Benoit; Cerussi, Albert; Hajjioui, Nassim; Li, Ang; Tromberg, Bruce J.; Sauer, Frank

    2007-03-01

    We have developed a novel 3D visualization and guidance system for handheld optical imaging devices. In this paper, the system is applied to measurements of breast/cancerous tissue optical properties using a handheld diffuse optical spectroscopy (DOS) instrument. The combined guidance system/DOS instrument becomes particularly useful for monitoring neoadjuvant chemotherapy in breast cancer patients and for longitudinal studies where measurement reproducibility is critical. The system uses relatively inexpensive hardware components and comprises a 6 degrees-of-freedom (DOF) magnetic tracking device including a DC field generator, three sensors, and a PCI card running on a PC workstation. A custom-built virtual environment combined with a well-defined workflow provide the means for image-guided measurements, improved longitudinal studies of breast optical properties, 3D reconstruction of optical properties within the anatomical map, and serial data registration. The DOS instrument characterizes tissue function such as water, lipid and total hemoglobin concentration. The patient lies on her back at a 45-degrees angle. Each spectral measurement requires consistent contact with the skin, and lasts about 5-10 seconds. Therefore a limited number of positions may be studied. In a reference measurement session, the physician acquires surface points on the breast. A Delaunay-based triangulation algorithm is used to build the virtual breast surface from the acquired points. 3D locations of all DOS measurements are recorded. All subsequently acquired surfaces are automatically registered to the reference surface, thus allowing measurement reproducibility through image guidance using the reference measurements.

  4. Weathering resistance of thin plasma polymer films on pre-coated steel =

    NASA Astrophysics Data System (ADS)

    Serra, Ricardo Gil Henriques

    O trabalho apresentado teve origem no projecto de investigacao “Tailored Thin Plasma Polymers Films for Surface Engineering of Coil Coated Steel”, financiado pelo Programa Europeu ECSC Steel Research. Sistemas de aco galvanizado pre-pintado em banda a base de poliester e poliuretano foram submetidos a um processo de polimerizacao por plasma onde um filme fino foi depositado de modo a modificar as propriedades de superficie. Foram usados reactores de catodo oco, microondas e radio frequencia para a deposicao do polimero fino. Os sistemas preparados foram analisados de modo a verificar a influencia do processo de polimerizacao por plasma na alteracao das propriedades barreira dos sistemas pre-pintados em banda. Foi estudado o efeito dos diferentes passos do processo de polimerizacao por plasma, bem como o efeito de diferentes variaveis operatorias. A mistura precursora foi variada de modo a modificar as propriedades da superficie de modo a poder vir a obter maior hidrofobicidade, maior resistencia a marcas digitais, bem como maior facilidade de limpeza. Os testes foram conduzidos em solucao de NaCl 0,5 M. Para o trabalho foram usadas tecnicas de analise da morfologia da superficie como Microscopia de Forca Atomica e Microscopia Electronica de Varrimento. As propriedades electroquimicas dos sistemas foram estudadas por Espectroscopia de Impedancia Electroquimica. A estrutura dos filmes gerados no processo de polimerizacao por plasma foi caracterizada por Microscopia de Transmissao Electronica. A modificacao das propriedades opticas devido ao processo de polimerizacao por plasma foi tambem obtida.

  5. An obligately aerobic soil bacterium activates fermentative hydrogen production to survive reductive stress during hypoxia

    PubMed Central

    Berney, Michael; Greening, Chris; Conrad, Ralf; Jacobs, William R.; Cook, Gregory M.

    2014-01-01

    Oxygen availability is a major factor and evolutionary force determining the metabolic strategy of bacteria colonizing an environmental niche. In the soil, conditions can switch rapidly between oxia and anoxia, forcing soil bacteria to remodel their energy metabolism accordingly. Mycobacterium is a dominant genus in the soil, and all its species are obligate aerobes. Here we show that an obligate aerobe, the soil actinomycete Mycobacterium smegmatis, adopts an anaerobe-type strategy by activating fermentative hydrogen production to adapt to hypoxia. This process is controlled by the two-component system DosR-DosS/DosT, an oxygen and redox sensor that is well conserved in mycobacteria. We show that DosR tightly regulates the two [NiFe]-hydrogenases: Hyd3 (MSMEG_3931-3928) and Hyd2 (MSMEG_2719-2718). Using genetic manipulation and high-sensitivity GC, we demonstrate that Hyd3 facilitates the evolution of H2 when oxygen is depleted. Combined activity of Hyd2 and Hyd3 was necessary to maintain an optimal NAD+/NADH ratio and enhanced adaptation to and survival of hypoxia. We demonstrate that fermentatively-produced hydrogen can be recycled when fumarate or oxygen become available, suggesting Mycobacterium smegmatis can switch between fermentation, anaerobic respiration, and aerobic respiration. Hydrogen metabolism enables this obligate aerobe to rapidly meet its energetic needs when switching between microoxic and anoxic conditions and provides a competitive advantage in low oxygen environments. PMID:25049411

  6. Quasiparticle density of states, localization, and distributed disorder in the cuprate superconductors

    NASA Astrophysics Data System (ADS)

    Sulangi, Miguel Antonio; Zaanen, Jan

    2018-04-01

    We explore the effects of various kinds of random disorder on the quasiparticle density of states of two-dimensional d -wave superconductors using an exact real-space method, incorporating realistic details known about the cuprates. Random on-site energy and pointlike unitary impurity models are found to give rise to a vanishing DOS at the Fermi energy for narrow distributions and low concentrations, respectively, and lead to a finite, but suppressed, DOS at unrealistically large levels of disorder. Smooth disorder arising from impurities located away from the copper-oxide planes meanwhile gives rise to a finite DOS at realistic impurity concentrations. For the case of smooth disorder whose average potential is zero, a resonance is found at zero energy for the quasiparticle DOS at large impurity concentrations. We discuss the implications of these results on the computed low-temperature specific heat, the behavior of which we find is strongly affected by the amount of disorder present in the system. We also compute the localization length as a function of disorder strength for various types of disorder and find that intermediate- and high-energy states are quasiextended for low disorder, and that states near the Fermi energy are strongly localized and have a localization length that exhibits an unusual dependence on the amount of disorder. We comment on the origin of disorder in the cuprates and provide constraints on these based on known results from scanning tunneling spectroscopy and specific heat experiments.

  7. Vaginal hemodynamic changes during sexual arousal in a rat model by diffuse optical spectroscopy (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Jeong, Hyeryun; Seong, Myeongsu; Lee, Hyun-Suk; Park, Kwangsung; Kim, Jae Gwan

    2017-02-01

    Not only men suffer from sexual dysfunction, but the number of women who have sexual dysfunction rises. Therefore, it is necessary to develop an objective diagnostic technique to examine the sexual dysfunction of female patients, who are afflicted with the disorders. For this purpose, we developed a diffuse optical spectroscopy (DOS) probe to measure the change of oxy-, deoxy-, and total hemoglobin concentration along with blood flow from vaginal wall of female rats. A cylindrical stainless steel DOS probe with a diameter of 3 mm was designed for the vaginal wall of rats which consisted of two lasers (785 and 850nm) and two spectrometers with a separation of 2 mm. A thermistor was placed on the top of the probe to measure the temperature change from vaginal wall during experiments. A modified Beer-Lambert's law is utilized to acquire the changes of oxy-, deoxy-, and total hemoglobin, and blood flow information is obtained by diffuse speckle contrast analysis technique. For the experiments, Sprague Dawley ( 400 g) female rats were divided into two groups (control and vaginal dryness model). Vaginal oxygenation, blood flow and temperature were continuously monitored before and after sexual around induced by apomorphine. After the measurement, histologic examination was performed to support the results from DOS probe in the vaginal wall. The hemodynamic information acquired by the DOS probe can be utilized to establish an objective and accurate standard of the female sexual disorders.

  8. A diversity-oriented synthesis strategy enabling the combinatorial-type variation of macrocyclic peptidomimetic scaffolds.

    PubMed

    Isidro-Llobet, Albert; Hadje Georgiou, Kathy; Galloway, Warren R J D; Giacomini, Elisa; Hansen, Mette R; Méndez-Abt, Gabriela; Tan, Yaw Sing; Carro, Laura; Sore, Hannah F; Spring, David R

    2015-04-21

    Macrocyclic peptidomimetics are associated with a broad range of biological activities. However, despite such potentially valuable properties, the macrocyclic peptidomimetic structural class is generally considered as being poorly explored within drug discovery. This has been attributed to the lack of general methods for producing collections of macrocyclic peptidomimetics with high levels of structural, and thus shape, diversity. In particular, there is a lack of scaffold diversity in current macrocyclic peptidomimetic libraries; indeed, the efficient construction of diverse molecular scaffolds presents a formidable general challenge to the synthetic chemist. Herein we describe a new, advanced strategy for the diversity-oriented synthesis (DOS) of macrocyclic peptidomimetics that enables the combinatorial variation of molecular scaffolds (core macrocyclic ring architectures). The generality and robustness of this DOS strategy is demonstrated by the step-efficient synthesis of a structurally diverse library of over 200 macrocyclic peptidomimetic compounds, each based around a distinct molecular scaffold and isolated in milligram quantities, from readily available building-blocks. To the best of our knowledge this represents an unprecedented level of scaffold diversity in a synthetically derived library of macrocyclic peptidomimetics. Cheminformatic analysis indicated that the library compounds access regions of chemical space that are distinct from those addressed by top-selling brand-name drugs and macrocyclic natural products, illustrating the value of our DOS approach to sample regions of chemical space underexploited in current drug discovery efforts. An analysis of three-dimensional molecular shapes illustrated that the DOS library has a relatively high level of shape diversity.

  9. Qual o Papel da Escola e da Mídia na Obtenção dos Conhecimentos Astronômicos?

    NASA Astrophysics Data System (ADS)

    da Cunha, W. S.; Voelzke, M. R.; Amaral, L. H.

    2007-08-01

    É amplamente reconhecido que as pessoas em geral têm grande fascínio e interesse pela Astronomia. Por outro lado, o conteúdo dessa área incluído no ensino formal está longe de ser abrangente e suficiente para suprir a demanda. Esse interesse permite aperfeiçoar a divulgação e o ensino não formal de Astronomia através da mídia aliando a adequação do conteúdo à expectativa das pessoas. A reforma do Currículo Básico da Escola Pública da maioria dos Estados brasileiros tem introduzido Astronomia desde a pré-escola até o Ensino Médio. Num estudo realizado com 1180 alunos do Ensino Médio de seis escolas estaduais, revelou-se através da aplicação de um formulário contendo questões que abordavam conhecimentos básicos em Astronomia, como foram adquiridos tais conhecimentos e à infra-estrutura da escola. Para 66,1% dos entrevistados o professor já fez alguma apresentação a respeito de Astronomia. O presente estudo revelou também que 54,4% dos alunos entrevistados adquiriram seus conhecimentos astronômicos na escola, 18,4% através da televisão e 27,1% afirmaram que seus conhecimentos foram obtidos através de outros tipos de mídia (internet, livros didáticos, filmes e revistas). Embora o estudo revele claramente que há certo equilíbrio no meio em que os alunos obtiveram seus conhecimentos astronômicos, a mídia busca não somente sua difusão, mas a disponibilização desse conhecimento de maneira correta, que às vezes, não é atingido, apresentando conceitos sem fundamentação e incorretos. Por outro lado, no dia-a-dia escolar, é comum encontrar professores que vêm para as aulas com concepções prévias, que podem diferir substancialmente das idéias a serem ensinadas, dificultando o aprendizado de futuros conceitos científicos. Uma avaliação criteriosa, avaliando as dificuldades dos professores em determinar o sentido correto dos conceitos e observando a metodologia que utilizam no ensino, poderá proporcionar uma melhor compreensão sobre as concepções alternativas, presentes no ensino de Astronomia.

  10. Biaxial seismic behaviour of reinforced concrete columns =

    NASA Astrophysics Data System (ADS)

    Rodrigues, Hugo Filipe Pinheiro

    A analise dos efeitos dos sismos mostra que a investigacao em engenharia sismica deve dar especial atencao a avaliacao da vulnerabilidade das construcoes existentes, frequentemente desprovidas de adequada resistencia sismica tal como acontece em edificios de betao armado (BA) de muitas cidades em paises do sul da Europa, entre os quais Portugal. Sendo os pilares elementos estruturais fundamentais na resistencia sismica dos edificios, deve ser dada especial atencao a sua resposta sob acoes ciclicas. Acresce que o sismo e um tipo de acao cujos efeitos nos edificios exige a consideracao de duas componentes horizontais, o que tem exigencias mais severas nos pilares comparativamente a acao unidirecional. Assim, esta tese centra-se na avaliacao da resposta estrutural de pilares de betao armado sujeitos a acoes ciclicas horizontais biaxiais, em tres linhas principais. Em primeiro lugar desenvolveu-se uma campanha de ensaios para o estudo do comportamento ciclico uniaxial e biaxial de pilares de betao armado com esforco axial constante. Para tal foram construidas quatro series de pilares retangulares de betao armado (24 no total) com diferentes caracteristicas geometricas e quantidades de armadura longitudinal, tendo os pilares sido ensaiados para diferentes historias de carga. Os resultados experimentais obtidos sao analisados e discutidos dando particular atencao a evolucao do dano, a degradacao de rigidez e resistencia com o aumento das exigencias de deformacao, a energia dissipada, ao amortecimento viscoso equivalente; por fim e proposto um indice de dano para pilares solicitados biaxialmente. De seguida foram aplicadas diferentes estrategias de modelacao nao-linear para a representacao do comportamento biaxial dos pilares ensaiados, considerando nao-linearidade distribuida ao longo dos elementos ou concentrada nas extremidades dos mesmos. Os resultados obtidos com as varias estrategias de modelacao demonstraram representar adequadamente a resposta em termos das curvas envolventes forca-deslocamento, mas foram encontradas algumas dificuldades na representacao da degradacao de resistencia e na evolucao da energia dissipada. Por fim, e proposto um modelo global para a representacao do comportamento nao-linear em flexao de elementos de betao armado sujeitos a acoes biaxiais ciclicas. Este modelo tem por base um modelo uniaxial conhecido, combinado com uma funcao de interacao desenvolvida com base no modelo de Bouc- Wen. Esta funcao de interacao foi calibrada com recurso a tecnicas de otimizacao e usando resultados de uma serie de analises numericas com um modelo refinado. E ainda demonstrada a capacidade do modelo simplificado em reproduzir os resultados experimentais de ensaios biaxiais de pilares.

  11. Investments and costs of oral health care for Family Health Care.

    PubMed

    Macêdo, Márcia Stefânia Ribeiro; Chaves, Sônia Cristina Lima; Fernandes, Antônio Luis de Carvalho

    2016-07-21

    To estimate the investments to implement and operational costs of a type I Oral Health Care Team in the Family Health Care Strategy. This is an economic assessment study, for analyzing the investments and operational costs of an oral health care team in the city of Salvador, BA, Northeastern Brazil. The amount worth of investments for its implementation was obtained by summing up the investments in civil projects and shared facilities, in equipments, furniture, and instruments. Regarding the operational costs, the 2009-2012 time series was analyzed and the month of December 2012 was adopted for assessing the monetary values in effect. The costs were classified as direct variable costs (consumables) and direct fixed costs (salaries, maintenance, equipment depreciation, instruments, furniture, and facilities), besides the indirect fixed costs (cleaning, security, energy, and water). The Ministry of Health's share in funding was also calculated, and the factors that influence cost behavior were described. The investment to implement a type I Oral Health Care Team was R$29,864.00 (US$15,236.76). The operational costs of a type I Oral Health Care Team were around R$95,434.00 (US$48,690.82) a year. The Ministry of Health's financial incentives for investments accounted for 41.8% of the implementation investments, whereas the municipality contributed with a 59.2% share of the total. Regarding operational costs, the Ministry of Health contributed with 33.1% of the total, whereas the municipality, with 66.9%. Concerning the operational costs, the element of heaviest weight was salaries, which accounted for 84.7%. Problems with the regularity in the supply of inputs and maintenance of equipment greatly influence the composition of costs, besides reducing the supply of services to the target population, which results in the service probably being inefficient. States are suggested to partake in funding, especially to cover the team's operational cost. Estimar os investimentos para implantação e os custos operacionais de uma Equipe de Saúde Bucal modalidade tipo I na Estratégia Saúde da Família. Estudo de avaliação econômica, tipo análise de investimentos e custos operacionais de uma equipe de saúde bucal no município de Salvador, Bahia, Brasil. O cálculo dos investimentos para implantação foi obtido pela soma dos investimentos em obras civis e instalações em rateio, equipamentos, móveis e instrumentais. Para os custos operacionais, foi analisada a série histórica de 2009 a 2012 e adotou-se o mês de dezembro de 2012 para levantamento dos valores monetários vigentes. Os custos foram classificados em custos diretos variáveis (materiais de consumo) e custos fixos diretos (salários, manutenção, depreciação do capital fixo dos equipamentos, instrumentais, móveis e edificações), além dos custos fixos indiretos (higienização, segurança, energia e água). Foi também calculada a participação do Ministério da Saúde no financiamento e descritos os fatores que influenciam o comportamento dos custos. O investimento para implantação de uma Equipe de Saúde Bucal modalidade tipo I foi de R$29.864,00. Os custos operacionais de uma Equipe de Saúde Bucal modalidade tipo I situaram-se em torno de R$95.434,00 por ano. Os incentivos financeiros do Ministério da Saúde para investimentos cobriram 41,8% dos investimentos com implantação, enquanto o município participou com 59,2% do total. Para os custos operacionais, a participação do Ministério da Saúde foi de 33,1%, enquanto o município participou com 66,9%. Dentro dos custos operacionais, o elemento de maior peso foram os salários, representando 84,7%. Problemas com a regularidade no abastecimento dos insumos e manutenção de equipamentos influenciam sobremaneira na composição dos custos, além de reduzir a oferta de serviços à população-alvo, resultando em provável ineficiência do serviço. Sugere-se o cofinanciamento estadual, especialmente para cobrir o custo operacional da equipe.

  12. Evaluation in health: participatory methodology and involvement of municipal managers.

    PubMed

    Almeida, Cristiane Andrea Locatelli de; Tanaka, Oswaldo Yoshimi

    2016-08-04

    To analyze scopes and limits of the use of participatory methodology of evaluation with municipal health managers and administrators. Qualitative research with health policymakers and managers of the Comissão Intergestores Regional (CIR - Regional Interagency Commission) of a health region of the state of Sao Paulo in Brazil. Representatives from seven member cities participated in seven workshops facilitated by the researchers, with the aim of assessing a specific problem of the care line, which would be used as a tracer of the system integrality. The analysis of the collected empirical material was based on the hermeneutic-dialectic methodology and aimed at the evaluation of the applied participatory methodology, according to its capacity of promoting a process of assessment capable to be used as a support for municipal management. With the participatory approach of evaluation, we were able to promote in-depth discussions with the group, especially related to the construction of integral care and to the inclusion of the user's perspective in decision-making, linked to the search for solution to concrete problems of managers. By joint exploration, the possibility of using data from electronic information systems was opened, as well as information coming directly from the users of the services, to enhance discussions and negotiations between partners. The participants were disbelievers of the replication potential of this type of evaluation without the direct monitoring of the academy, given the difficulty of organizing the process in everyday life, already taken by emergency and political issues. Evaluations of programs and services carried out within the Regional Interagency Commission, starting from the local interest and facilitating the involvement of its members by the use of participatory methodologies, can contribute to the construction of integral care. To the extent that the act of evaluating stay invested with greater significance to the local actors, its involvement with the evaluations at the federal level can also be stimulated. Analisar alcances e limites do uso de metodologia participativa de avaliação junto a gestores e gerentes municipais de saúde. Pesquisa qualitativa com gestores e gerentes de saúde da Comissão Intergestores Regional de uma região de saúde do estado de São Paulo. Representantes de sete municípios membros participaram de sete oficinas facilitadas pelos pesquisadores, com o objetivo de avaliar um problema específico da linha de cuidados sob a perspectiva da integralidade. A análise do material empírico coletado baseou-se na metodologia hermenêutica-dialética e visou a avaliação da metodologia participativa aplicada, segundo sua capacidade de promover um processo de avaliação passível de ser utilizado como suporte à gestão municipal. Com a abordagem participativa de avaliação, foi possível promover debates em profundidade com o grupo, principalmente relacionados à construção da integralidade da atenção e à inclusão da perspectiva do usuário na tomada de decisão, de forma vinculada à busca de solução para problemas concretos dos gestores. Mediante a exploração conjunta, foi aberta a possibilidade de utilização de dados advindos dos sistemas eletrônicos de informação, bem como de informações advindas diretamente dos usuários dos serviços, para enriquecer debates e negociações entre parceiros. Os participantes se mostraram descrentes do potencial de replicação deste tipo de avaliação sem o acompanhamento direto da academia, dada a dificuldade de organização do processo no cotidiano, já tomado por questões emergenciais e políticas. Avaliações de programas e serviços realizadas no âmbito da Comissão Intergestores Regional, partindo do interesse local e facilitando o envolvimento de seus membros pelo uso de metodologias participativas, podem contribuir para a construção da integralidade do cuidado. Na medida em que o ato de avaliar fique investido de maior significado para os atores locais, seu envolvimento com as avaliações em nível federal poderá ser também estimulado.

  13. IOS: PDP 11/45 formatted input/output task stacker and processer. [In MACRO-II

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Koschik, J.

    1974-07-08

    IOS allows the programer to perform formated Input/Output at assembly language level to/from any peripheral device. It runs under DOS versions V8-O8 or V9-19, reading and writing DOS-compatible files. Additionally, IOS will run, with total transparency, in an environment with memory management enabled. Minimum hardware required is a 16K PDP 11/45, Keyboard Device, DISK (DK,DF, or DC), and Line Frequency Clock. The source language is MACRO-11 (3.3K Decimal Words).

  14. The Effects of Denial-of-Service Attacks on Secure Time-Critical Communications in the Smart Grid

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Fengli; Li, QInghua; Mantooth, Homer Alan

    2016-04-02

    According to IEC 61850, many smart grid communications require messages to be delivered in a very short time. –Trip messages and sample values applied to the transmission level: 3 ms –Interlocking messages applied to the distribution level: 10 ms •Time-critical communications are vulnerable to denial-of-service (DoS) attacks –Flooding attack: Attacker floods many messages to the target network/machine. We conducted systematic, experimental study about how DoS attacks affect message delivery delays.

  15. Generalized Gilat-Raubenheimer method for density-of-states calculation in photonic crystals

    NASA Astrophysics Data System (ADS)

    Liu, Boyuan; Johnson, Steven G.; Joannopoulos, John D.; Lu, Ling

    2018-04-01

    An efficient numerical algorithm is the key for accurate evaluation of density of states (DOS) in band theory. The Gilat-Raubenheimer (GR) method proposed in 1966 is an efficient linear extrapolation method which was limited in specific lattices. Here, using an affine transformation, we provide a new generalization of the original GR method to any Bravais lattices and show that it is superior to the tetrahedron method and the adaptive Gaussian broadening method. Finally, we apply our generalized GR method to compute DOS of various gyroid photonic crystals of topological degeneracies.

  16. Remote media vision-based computer input device

    NASA Astrophysics Data System (ADS)

    Arabnia, Hamid R.; Chen, Ching-Yi

    1991-11-01

    In this paper, we introduce a vision-based computer input device which has been built at the University of Georgia. The user of this system gives commands to the computer without touching any physical device. The system receives input through a CCD camera; it is PC- based and is built on top of the DOS operating system. The major components of the input device are: a monitor, an image capturing board, a CCD camera, and some software (developed by use). These are interfaced with a standard PC running under the DOS operating system.

  17. Ionospheric Irregularities Predictions and Plumes Characterization for Satellite Data Validation and Calibration

    DTIC Science & Technology

    2014-01-17

    at São José dos Campos, São Paulo - Brazil Good S4 agreement for the 6 receivers and for moderate scintillations – no strong scintillations tested...Space Research - INPE Fundação de Ciências, Aplicações e Tecnologia Espaciais, Av. Dr. João Guilhermino, 429/11 – São José dos Campos, São Paulo ...The ionospheric plumes were characterized for 3 longitudinal sectors (east of Brazil , Peruvian coast and pacific zone)using VHF radars and algorithms

  18. Characterisation of gas and particle emissions from wildfires =

    NASA Astrophysics Data System (ADS)

    Vicente, Ana Margarida Proenca

    Os incendios florestais sao uma importante fonte de emissao de compostos gasosos e de aerossois. Em Portugal, onde a maioria dos incendios ocorre no norte e centro do pais, os incendios destroem todos os anos milhares de hectares, com importantes perdas em termos economicos, de vidas humanas e qualidade ambiental. As emissoes podem alterar consideravelmente a quimica da atmosfera, degradar a qualidade do ar e alterar o clima. Contudo, a informacao sobre as carateristicas das emissoes dos incendios florestais nos paises do Mediterrâneo e limitada. Tanto a nivel nacional como internacional, existe um interesse crescente na elaboracao de inventarios de emissoes e de regulamentos sobre as emissoes de carbono para a atmosfera. Do ponto de vista atmosferico da monitorizacao atmosferica, os incendios sao considerados um desafio, dada a sua variabilidade temporal e espacial, sendo de esperar um aumento da sua frequencia, dimensao e severidade, e tambem porque as estimativas de emissoes dependem das carateristicas dos biocombustiveis e da fase de combustao. O objetivo deste estudo foi quantificar e caraterizar as emissoes de gases e aerossois de alguns dos mais representativos incendios florestais que ocorreram no centro de Portugal nos veroes de 2009 e de 2010. Efetuou-se a colheita de amostras de gases e de duas fracoes de particulas (PM2.5 e PM2.5-10) nas plumas de fumo em sacos Tedlar e em filtros de quartzo acoplados a um amostrador de elevado volume, respetivamente. Os hidrocarbonetos totais (THC) e oxidos de carbono (CO e CO2) nas amostras gasosas foram analisados em instrumentos automaticos de ionizacao de chama e detetores nao dispersivos de infravermelhos, respetivamente. Para algumas amostras, foram tambem quantificados alguns compostos de carbonilo apos reamostragem do gas dos sacos Tedlar em cartuchos de silica gel revestidos com 2,4-dinitrofenilhidrazina (DNPH), seguida de analise por cromatografia liquida de alta resolucao. Nas particulas, analisou-se o carbono orgânico e elementar (tecnica termo-optica), ioes soluveis em agua (cromatografia ionica) e elementos (espectrometria de massa com plasma acoplado por inducao ou analise instrumental por ativacao com neutroes). A especiacao orgânica foi obtida por cromatografia gasosa acoplada a espectrometria de massa apos extracao com recurso a varios solventes e separacao dos extratos orgânicos em diversas classes de diferentes polaridades atraves do fracionamento com silica gel. Tendo em conta que a estimativa das emissoes dos incendios florestais requer um conhecimento de fatores de emissao apropriados para cada biocombustivel, a base de dados abrangente obtida neste estudo e potencialmente util para atualizar os inventarios de emissoes. Tem vindo a ser observado que a fase de combustao latente sem chama, a qual pode ocorrer simultaneamente com a fase de chama e durar varias horas ou dias, pode contribuir para uma quantidade consideravel de poluentes atmosfericos, pelo que os fatores de emissao correspondentes devem ser considerados no calculo das emissoes globais de incendios florestais. Devido a falta de informacao detalhada sobre perfis quimicos de emissao, a base de dados obtida neste estudo pode tambem ser util para a aplicacao de modelos no recetor no sul da Europa. (Abstract shortened by ProQuest.).

  19. Comparative study of knowledge about oral cancer among undergraduate dental students.

    PubMed

    Silva, Samara Ribeiro da; Juliano, Yara; Novo, Neil Ferreira; Weinfeld, Ilan

    2016-01-01

    To evaluate and compare the knowledge of dental undergraduate students about oral cancer. The students were divided into two groups according to semester attended in the undergraduate course: Group A, the first semester; and Group B, seventh semester. They were asked to answer a questionnaire about epidemiology, risk factors, clinical aspects, therapeutic solutions and oral self-examination. For statistical analysis, the Fisher's exact test, the Cochran's G test and Kendall's concordance test were used, with significance level set at 0.05. Regarding the prevalent sex, only 8.0% of Group A and 56.0% of Group B judged males as the frequent affected by the disease (p=0.0006). In terms of age, 84.0% of the Group B and 44.0% of the Group A estimated that most cases were diagnosed over 40 years (p=0.0072). Smoking was identified as the major risk factor for 64.0% and 91.6% of Groups A and B, respectively (p=0.0110). On issues related to sex, ethnicity, age, risk factors, self-examination, treatment, professional responsible for treatment and profile of an individual with the disease, the seventh-semester showed significantly higher correct answer percentages than first-semester undergraduates. There was significant correlation between the right and wrong answers given by first and seventh semester students, making necessary a specific approach directed to their lack of knowledge. Avaliar e comparar o conhecimento de acadêmicos de odontologia sobre câncer bucal. Os acadêmicos foram divididos em dois grupos, de acordo com o semestre cursado na graduação: Grupo A, primeiro semestre; e Grupo B: sétimo semestre. Eles foram convidados a responderem um questionário referente a epidemiologia, fatores de risco, aspectos clínicos, soluções terapêuticas e autoexame bucal. Para a análise estatística dos resultados, foram utilizados o teste exato de Fisher, o teste G de Cochran e o teste de concordância de Kendall, com nível de significância estabelecido em 0,05. Somente 8,0% do Grupo A e 56,0% do Grupo B julgaram o sexo masculino como aquele frequentemente acometido pela lesão (p=0,0006). Em relação à faixa etária, 84,0% do Grupo B e 44,0% do Grupo A estimaram que a maioria dos casos era diagnosticada acima dos 40 anos (p=0,0072). O tabagismo foi apontado como principal fator de risco por 64,0% e 91,6% dos alunos dos Grupos A e B, respectivamente (p=0,0110). Nas questões referentes a sexo, etnia, faixa etária, fatores de risco, autoexame, tratamento, profissional responsável pelo tratamento e perfil de um indivíduo portador da lesão, os alunos do sétimo semestre apresentaram percentagens de respostas corretas significantemente maiores que as dos discentes do primeiro semestre. Houve significativa concordância entre os erros e acertos dos discentes do primeiro e sétimo semestres, sendo necessária uma abordagem específica direcionada à deficiência por eles apresentadas.

  20. Judicial demand of medications through the Federal Justice of the State of Paraná.

    PubMed

    Nisihara, Renato Mitsunori; Possebom, Ana Carolina; Borges, Luiza de Martino Cruvinel; Shwetz, Ana Claudia Athanasio; Bettes, Fernanda Francis Benevides

    2017-01-01

    To describe the profile of lawsuits related to drug requests filled at the Federal Justice of the State of Paraná. A cross-sectional study, and the data were obtained through consulting the lawsuits at the online system of the Federal Justice of Paraná. Out of 347 lawsuits included in the study, 55% of plaintiffs were women, with a median age of 56 years. Oncology was the field with more requests (23.6%), and the highest mean costs. A wide variety of diseases and broad variety of requested drugs were found in the lawsuits. Approximately two-thirds of them were requested by the brand name, and the most often requested drugs were palivizumab and tiotropium bromide. Only 14.5% of the requested medicines were registered in the National Medication Register. The Public Defender's Office filled actions in 89.6% of cases and all lawsuits had an interim relief. The mean time for approval was 35 days and 70% of requests were granted. Oncology was the field with the highest demand for medicines at the Federal Justice of Paraná in 2014. A great variety of medications was requested. The Public Defender´s Office represented most lawsuits. All demands had an interim relief, and the majority of requests were granted, within an average of 35 days. Descrever o perfil das ações que solicitam medicamentos ajuizadas na Justiça Federal do Paraná. Estudo transversal descritivo, cujos dados foram obtidos por meio de consulta aos processos no sistema on-line da Justiça Federal do Paraná. Dentre os 347 processos incluídos no estudo, 55% dos autores eram mulheres, com mediana da idade de 56 anos, sendo a área mais procurada a oncologia (23,6%). A área oncológica também foi a que apresentou maiores custos médios. Foi ampla a variedade de doenças geradoras das ações e também foi consequentemente grande a variedade de medicamentos solicitados. Cerca de dois terços dos fármacos foram solicitados pelo nome comercial, e os mais requeridos foram o palivizumabe e brometo de tiotrópio. Apenas 14,5% dos medicamentos solicitados estavam cadastrados no Registro Nacional de Medicamentos. A Defensoria Pública impetrou as ações em 89,6% dos casos. Todos os processos pediam antecipação de tutela do medicamento. O tempo médio para deferimento foi de 35 dias, sendo que 70% dos pedidos foram deferidos. A área com maior número de casos de demanda de medicamentos na Justiça Federal do Paraná no ano de 2014 foi de Oncologia. Observou-se grande variedade de medicamentos solicitados. A maioria das ações foi impetrada pela Defensoria Pública. Todas as demandas exigiram antecipação de tutela, sendo que a maioria dos pedidos foram deferidos, num prazo médio de 35 dias.

  1. METALLURGICAL PROGRAMS: CALCULATION OF MASS FROM VOLUME, DENSITY OF MIXTURES, AND CONVERSION OF ATOMIC TO WEIGHT PERCENT

    NASA Technical Reports Server (NTRS)

    Degroh, H.

    1994-01-01

    The Metallurgical Programs include three simple programs which calculate solutions to problems common to metallurgical engineers and persons making metal castings. The first program calculates the mass of a binary ideal (alloy) given the weight fractions and densities of the pure components and the total volume. The second program calculates the densities of a binary ideal mixture. The third program converts the atomic percentages of a binary mixture to weight percentages. The programs use simple equations to assist the materials staff with routine calculations. The Metallurgical Programs are written in Microsoft QuickBASIC for interactive execution and have been implemented on an IBM PC-XT/AT operating MS-DOS 2.1 or higher with 256K bytes of memory. All instructions needed by the user appear as prompts as the software is used. Data is input using the keyboard only and output is via the monitor. The Metallurgical programs were written in 1987.

  2. Considerations for applying VARSKIN mod 2 to skin dose calculations averaged over 10 cm2.

    PubMed

    Durham, James S

    2004-02-01

    VARSKIN Mod 2 is a DOS-based computer program that calculates the dose to skin from beta and gamma contamination either directly on skin or on material in contact with skin. The default area for calculating the dose is 1 cm2. Recently, the U.S. Nuclear Regulatory Commission issued new guidelines for calculating shallow dose equivalent from skin contamination that requires the dose be averaged over 10 cm2. VARSKIN Mod 2 was not filly designed to calculate beta or gamma dose estimates averaged over 10 cm2, even though the program allows the user to calculate doses averaged over 10 cm2. This article explains why VARSKIN Mod 2 overestimates the beta dose when applied to 10 cm2 areas, describes a manual method for correcting the overestimate, and explains how to perform reasonable gamma dose calculations averaged over 10 cm2. The article also describes upgrades underway in Varskin 3.

  3. First-principles study of bandgap tuning in Ge1-xPbxSe

    NASA Astrophysics Data System (ADS)

    Lohani, Himanshu

    2018-03-01

    Narrow bandgap and its tuning are important aspects of materials for their technological applications. In this context group IV-VI semiconductors are one of the interesting candidates. In this paper, we explore the possibility of bandgap tuning in one of the family member of this family GeSe by using isoelectronic Pb doping. Our study is first-principles based electronic structure calculations of Ge1-xPbxSe. This study reveals that the Ge-p and Se-p states are strongly hybridized in GeSe and shows a gap in the DOS at Ef in GeSe. This gap reduces systematically with simultaneous enhancement of the states in the near Ef region as a function of Pb doping. This leads tuning of the indirect bandgap in GeSe via Pb doping. The results of the indirect bandgap decrement are consistent with the experimental findings. We propose a mechanism where the electrostatic effect of dopant Pb cation could be responsible for these changes in the electronic structure of GeSe.

  4. Model for determination of mid-gap states in amorphous metal oxides from thin film transistors

    NASA Astrophysics Data System (ADS)

    Bubel, S.; Chabinyc, M. L.

    2013-06-01

    The electronic density of states in metal oxide semiconductors like amorphous zinc oxide (a-ZnO) and its ternary and quaternary oxide alloys with indium, gallium, tin, or aluminum are different from amorphous silicon, or disordered materials such as pentacene, or P3HT. Many ZnO based semiconductors exhibit a steep decaying density of acceptor tail states (trap DOS) and a Fermi level (EF) close to the conduction band energy (EC). Considering thin film transistor (TFT) operation in accumulation mode, the quasi Fermi level for electrons (Eq) moves even closer to EC. Classic analytic TFT simulations use the simplification EC-EF> `several'kT and cannot reproduce exponential tail states with a characteristic energy smaller than 1/2 kT. We demonstrate an analytic model for tail and deep acceptor states, valid for all amorphous metal oxides and include the effect of trap assisted hopping instead of simpler percolation or mobility edge models, to account for the observed field dependent mobility.

  5. Calculation of Weibull strength parameters, Batdorf flaw density constants and related statistical quantities using PC-CARES

    NASA Technical Reports Server (NTRS)

    Szatmary, Steven A.; Gyekenyesi, John P.; Nemeth, Noel N.

    1990-01-01

    This manual describes the operation and theory of the PC-CARES (Personal Computer-Ceramic Analysis and Reliability Evaluation of Structures) computer program for the IBM PC and compatibles running PC-DOS/MS-DOR OR IBM/MS-OS/2 (version 1.1 or higher) operating systems. The primary purpose of this code is to estimate Weibull material strength parameters, the Batdorf crack density coefficient, and other related statistical quantities. Included in the manual is the description of the calculation of shape and scale parameters of the two-parameter Weibull distribution using the least-squares analysis and maximum likelihood methods for volume- and surface-flaw-induced fracture in ceramics with complete and censored samples. The methods for detecting outliers and for calculating the Kolmogorov-Smirnov and the Anderson-Darling goodness-of-fit statistics and 90 percent confidence bands about the Weibull line, as well as the techniques for calculating the Batdorf flaw-density constants are also described.

  6. Theoretical approach to evaluate graphene/PANI composite as highly selective ammonia sensor

    NASA Astrophysics Data System (ADS)

    Guo, Zhi; Liao, Ningbo; Zhang, Miao; Xue, Wei

    2018-09-01

    The incorporation of graphene is an effective way to enhance the sensitivity of polyaniline (PANI) gas sensors, while the interaction mechanism between gas and graphene/PANI composite system is still not clear. In this work, the interaction between NH3, NO, CO, H2 and graphene/PANI are investigated by density functional theory and molecular dynamics simulations. Based on the obtained adsorption energy, Mulliken charge and band gap, graphene/PANI exhibits much higher sensitivity towards NH3 gas than the other three gases. The adsorption of NH3 on graphene/PANI causes a clear increase of the DOS above the Fermi level, thus changing the conductivity of graphene/PANI and making the sensing feasible. The further comparative research on gases diffusion properties demonstrates that the composite show excellent adsorption capacity towards NH3 gas molecules. Our results show graphene/PANI system can detect NH3 gas with high sensitivity and selectivity, enabling it to be a promising sensing material of NH3.

  7. Dependence of Mobility on Density of Gap States in Organics by GAMEaS - Gate Modulated Activation Energy Spectroscopy

    NASA Astrophysics Data System (ADS)

    So, Woo-Young; Lang, David; Ramirez, Arthur

    2008-03-01

    We develop a spectroscopic method for determining the density of states (DOS) in the energy gap - GAte Modulated activation Energy Spectroscopy (GAMEaS), We also report the relationship of these gap states to the mobility of organic field-effect-transistors (FETs). We find that the field-effect mobility is parameterized by two factors: (1) the free-carrier mobility and (2) the ratio of the free carrier density to the total carrier density induced by the gate bias. We show that the highest mobility FETs have shallow exponential band tails of localized states with characteristic slope of 1/kT at 300K. Most remarkably, state-of-the-art crystalline FETs fabricated from rubrene, pentacene, and tetracene all have a very high free-carrier mobility, up to 200cm2/Vsec at 300K, with the somewhat lower effective mobilities dominated by localized gap states. This strongly suggests that further improvements in device performance could be possible with enhanced material quality.

  8. Investigação dos perfís temporais de alta resolução de explosões solares tipo-III decimétricas

    NASA Astrophysics Data System (ADS)

    Cecatto, J. R.; Fernandes, F. C. R.; Sawant, H. S.; Madsen, F. R. H.

    2003-08-01

    Explosões solares tipo-III indicam a presença de feixes de elétrons acelerados durante "flares" solares. Sua investigação fornece informações tanto sobre os processos de aceleração de partículas quanto das características do agente causador e do local de aceleração. Explosões tipo-III decimétricas são geradas por feixes de elétrons viajando através de arcos magnéticos densos da baixa coroa solar. Os perfís temporais destes fenômenos, quando tomados com alta resolução, informam sobre os mecanismos de aceleração de partículas do feixe e o meio de transporte da energia liberada a partir da região de aceleração. Usando o Brazilian Solar Spectroscope (BSS), em operação no INPE, foram registradas dezenas de explosões tipo-III decimétricas, dentro da faixa de 2050-2250 MHz com alta resolução temporal (20 ms), em 13 de setembro de 2001, entre 13:00 e 16:10 UT. Foram selecionadas 10 explosões isoladas para uma investigação estatística detalhada de seus perfís temporais, em todos os cerca de 50 canais de freqüência. Os resultados indicam que cerca de 70% dos perfís temporais são complexos tanto durante a subida quanto descida. Os 30% restantes indicam que os perfís da subida podem ser bem representados, na maioria dos casos, por um processo não-linear e uma parcela significativa por processos lineares. Os perfís temporais da descida são dominados por um decaimento não-linear. Neste trabalho, será efetuada uma análise dos perfís temporais, tanto durante a subida quanto descida do fluxo, para as explosões selecionadas, em termos dos prováveis mecanismos de aceleração e relaxamento. 2

  9. The influence of climate change on wine production - the case of the Touriga Nacional grape variety (Quinta dos Termos, Portugal)

    NASA Astrophysics Data System (ADS)

    Fonseca, João

    2017-04-01

    The regional and local climate, heavily influenced by global climate change, has strong implications for agriculture. Wine production which has specific characteristics in terms of climate and soil is undoubtedly one of the economic activities strongly influenced by climate change. Quinta dos Termos located in Beira Interior (Belmonte, Portugal) is the largest wine producer in the DOC Beira Interior region, producing premium to hiper premium wines of excellence, marketed at both national and international levels, and cultivates the vineyards according to the rules of Integrated Crop Management. Moreover, grapes are free from herbicides, pesticides or any other chemicals that can be harmful to the environment and health. These factors have contributed to the socio-economic development of the region, creating wealth, favoring employment and promoting tourism. The quality of the wines produced by Quinta dos Termos result from its terroir, given its granite region, the sun exposure, the wind protection, the atmospheric humidity and temperature, the soil water content, the mineralogical/organic composition and soil porosity. These factors favor unique conditions for the cultivation of Touriga Nacional grape variety, which is recognized by its extremely complex color and aroma, which allows the production of wines with great balance and a good ageing potential. Touriga Nacional, a red grape variety of Portuguese origin with high qualitative excellence and reputation and much appreciated worldwide, is versatile to several types of soils and resistant to high thermal amplitudes. Nevertheless, the climatic changes that has been gradually verified, the type of crop management, and in particular the reputation of Touriga Nacional grape variety, may be compromised in the long term, given that these characteristics are strongly influenced by the climate and soil. Aware of that, Quinta dos Termos has been performing a monitoring of the vineyards in terms of pedological treatment, disease control and water stress. With the present essay we intend to present the results achieved by the monitoring of the main influencing factors in grape production and therefore the quality of wines produced, over the years, by Quinta dos Termos.

  10. Analysis of electrocautery generated smoke by chromatographic-mass spectrometry.

    PubMed

    Kalil, Jefferson; Pessine, Francisco B T; Fidelis, Carlos H V; Menezes, Fabio H; Palma, Paulo Cesar Rodrigues

    2016-01-01

    to analyze the chemical components of the smoke from electrocautery from coagulating muscle and liver tissues of pigs. we collected smoke produced by electrocautery applied to porcine tissue in previously evacuated bottles, with qualitative and quantitative analysis of the compounds present through the hyphenated technique gas chromatography / mass spectrometry. there was a majority of decanal aldehyde in the fumes from the subcutaneous, muscle and liver tissues. Fumes of subcutaneous and muscular tissues also showed the presence of hexanal and phenol. In the fumes of subcutaneous and liver tissues we also found toluene and limonene and, finally, nonanal smoke was present in the muscle and liver tissues. there is increasing evidence showing that smoke from electrocautery used in subcutaneous, muscle and liver tissue is harmful to human health. Thus, there is need to reduce exposure to it or wear masks with filters capable of retaining these particles. analisar quimicamente os componentes da fumaça do eletrocautério, provenientes da coagulação de tecidos, muscular e hepático de suino. coleta de fumaça produzida por eletrocauterização de tecido porcino em frascos previamente evacuados com análise qualitativa e quantitativa dos compostos presentes, através de técnica hifenada, cromatografia a gás/espectrometria de massas. houve presença majoritária do aldeído decanal nas fumaças provenientes dos tecidos subcutâneo, muscular e hepático. Fumaças dos tecidos subcutâneo e muscular mostraram também a presença de hexanal e fenol. Nas fumaças dos tecidos subcutâneo e hepático foram encontrados ainda tolueno e limoneno e, por fim, nonanal estava presente nas fumaças dos tecidos muscular e hepático. há número crescente de evidências mostrando que fumaça proveniente de eletrocauterização de tecidos subcutâneo, muscular e hepático é nociva à saúde de seres humanos. Portanto, há necessidade de reduzir a exposição a ela ou usar máscara com filtro capaz de reter essas partículas.

  11. New tools for subsurface imaging of 3D seismic Node data in hydrocarbon exploration =

    NASA Astrophysics Data System (ADS)

    Benazzouz, Omar

    A aquisicao de dados sismicos de reflexao multicanal 3D/4D usando Ocean Bottom NODES de 4 componentes constitui atualmente um sector de importancia crescente no mercado da aquisicao de dados reflexao sismica marinha na industria petrolifera. Este tipo de dados permite obter imagens de sub-superficie de alta qualidade, com baixos niveis de ruido, banda larga, boa iluminacao azimutal, offsets longos, elevada resolucao e aquisicao de tanto ondas P como S. A aquisicao de dados e altamente repetitiva e portanto ideal para campanhas 4D. No entanto, existem diferencas significativas na geometria de aquisicao e amostragem do campo de ondas relativamente aos metodos convencionais com streamers rebocados a superficie, pelo que e necessario desenvolver de novas ferramentas para o processamento deste tipo de dados. Esta tese investiga tres aspectos do processamento de dados de OBSs/NODES ainda nao totalmente resolvidos de forma satisfatoria: a deriva aleatoria dos relogios internos, o posicionamento de precisao dos OBSs e a implementacao de algoritmos de migracao prestack 3D em profundidade eficientes para obtencao de imagens precisas de subsuperficie. Foram desenvolvidos novos procedimentos para resolver estas situacoes, que foram aplicados a dados sinteticos e a dados reais. Foi desenvolvido um novo metodo para deteccao e correccao de deriva aleatoria dos relogios internos, usando derivadas de ordem elevada. Foi ainda desenvolvido um novo metodo de posicionamento de precisao de OBSs usando multilateracao e foram criadas ferramentas de interpolacao/extrapolacao dos modelos de velocidades 3D de forma a cobrirem a extensao total area de aquisicao. Foram implementados algoritmos robustos de filtragem para preparar o campo de velocidades para o tracado de raios e minimizar os artefactos na migracao Krichhoff pre-stack 3D em profundidade. Os resultados obtidos mostram um melhoramento significativo em todas as situacoes analisadas. Foi desenvolvido o software necessario para o efeito e criadas solucoes computacionais eficientes. As solucoes computacionais desenvolvidas foram integradas num software standard de processamento de sismica (SPW) utilizado na industria, de forma a criar, conjuntamente com as ferramentas ja existentes, um workflow de processamento integrado para dados de OBS/NODES, desde a aquisicao e controle de qualidade a producao dos volumes sismicos migrados pre-stack em profundidade.

  12. On Ensino de Astronomia nas Cidades de Ribeirão Pires e Rio Grande da Serra

    NASA Astrophysics Data System (ADS)

    Faria, R. Z.; Voelzke, M. R.

    2007-08-01

    Apesar da astronomia ser um dos temas indicados pelos Parâmetros Curriculares Nacionais, observa-se que poucas mudanças ocorreram desde a implementação do mesmo em sala de aula. A presente pesquisa diz respeito sobre como os tópicos de astronomia estão sendo abordados pelos professores no ensino médio. Optou-se por aplicar um questionário com os professores que ministram a disciplina de física. Os mesmos trabalham em escolas estaduais situadas nas cidades de Ribeirão Pires e Rio Grande da Serra, ambas subordinadas a Diretoria de Ensino de Mauá, no Estado de São Paulo. O questionário foi aplicado durante o 2° semestre de 2006. Até o momento os resultados são preliminares. Dos 82,0% dos professores que responderam ao questionário no município de Rio Grande da Serra, 66,7% não aplicaram nenhum tópico de astronomia, 77,8% não utilizaram qualquer tipo de programa computacional, 66,7% não utilizaram laboratório, que 77,8% nunca levaram os alunos a museus e ou planetários e que 66,7% não indicaram qualquer tipo de revista ou livro sobre astronomia aos seus alunos. No município de Ribeirão Pires, 53,3% dos professores responderam ao questionário, destes 75,0% não aplicaram nenhum tópico de astronomia, 93,8% não utilizaram qualquer tipo de programa computacional, 75,0% não utilizaram laboratório, 81,3% nunca levaram os alunos a museus e ou planetário e 56,3% não indicaram qualquer tipo de revista ou livro sobre astronomia ao seus alunos. Apesar da maioria dos professores reconhecerem que o conteúdo de astronomia influi na formação do jovem, os mesmos não incluem o tema em seus planejamentos escolares.

  13. Análise dos fatores de risco relacionados às amputações maiores e menores de membros inferiores em hospital terciário

    PubMed Central

    de Jesus-Silva, Seleno Glauber; de Oliveira, João Pedro; Brianezi, Matheus Henrique Colepicolo; Silva, Melissa Andreia de Moraes; Krupa, Arturo Eduardo; Cardoso, Rodolfo Souza

    2017-01-01

    Resumo Contexto As amputações dos membros inferiores, sejam definidas como maiores ou menores, são um grave problema de saúde, com altos índices de morbimortalidade e de relevante impacto social. Diferentes características clínicas dos pacientes parecem estar relacionadas aos diferentes tipos de amputação realizados. Objetivos Analisar os fatores de risco presentes em pacientes submetidos a amputações de membros inferiores em hospital terciário. Métodos Estudo retrospectivo, transversal, envolvendo 109 pacientes submetidos a amputação de membro inferior em um período de 31 meses, através da análise de gênero e idade, 15 dados clínicos e cinco parâmetros laboratoriais presentes no momento da admissão. Os dados foram submetidos a estatística descritiva e comparativa através do teste t de Student não pareado (para variáveis numéricas), e dos testes de Mann-Whitney e exato de Fisher (para variáveis categóricas). Resultados Das 109 amputações realizadas, 59 foram maiores e 50 menores. A maioria dos pacientes era do gênero masculino (65%), e a média de idade foi de 65 anos (mín. 39, máx. 93). Dentre os fatores de risco observados, idade avançada, acidente vascular encefálico, isquemia, sepse e níveis baixos de hemoglobina e hematócrito estavam estatisticamente mais relacionados às amputações maiores (p < 0,05). Diabetes melito, neuropatia e pulsos distais palpáveis foram fatores mais associados às amputações menores. Conclusões Os níveis das amputações de membros inferiores estão relacionados a diferentes fatores de risco. Os quadros isquêmicos mais graves e de maior morbidade estiveram associados a amputações maiores, enquanto a neuropatia e perfusão preservada, mais relacionados às amputações menores. PMID:29930618

  14. DoS detection in IEEE 802.11 with the presence of hidden nodes

    PubMed Central

    Soryal, Joseph; Liu, Xijie; Saadawi, Tarek

    2013-01-01

    The paper presents a novel technique to detect Denial of Service (DoS) attacks applied by misbehaving nodes in wireless networks with the presence of hidden nodes employing the widely used IEEE 802.11 Distributed Coordination Function (DCF) protocols described in the IEEE standard [1]. Attacker nodes alter the IEEE 802.11 DCF firmware to illicitly capture the channel via elevating the probability of the average number of packets transmitted successfully using up the bandwidth share of the innocent nodes that follow the protocol standards. We obtained the theoretical network throughput by solving two-dimensional Markov Chain model as described by Bianchi [2], and Liu and Saadawi [3] to determine the channel capacity. We validated the results obtained via the theoretical computations with the results obtained by OPNET simulator [4] to define the baseline for the average attainable throughput in the channel under standard conditions where all nodes follow the standards. The main goal of the DoS attacker is to prevent the innocent nodes from accessing the channel and by capturing the channel’s bandwidth. In addition, the attacker strives to appear as an innocent node that follows the standards. The protocol resides in every node to enable each node to police other nodes in its immediate wireless coverage area. All innocent nodes are able to detect and identify the DoS attacker in its wireless coverage area. We applied the protocol to two Physical Layer technologies: Direct Sequence Spread Spectrum (DSSS) and Frequency Hopping Spread Spectrum (FHSS) and the results are presented to validate the algorithm. PMID:25685510

  15. DoS detection in IEEE 802.11 with the presence of hidden nodes.

    PubMed

    Soryal, Joseph; Liu, Xijie; Saadawi, Tarek

    2014-07-01

    The paper presents a novel technique to detect Denial of Service (DoS) attacks applied by misbehaving nodes in wireless networks with the presence of hidden nodes employing the widely used IEEE 802.11 Distributed Coordination Function (DCF) protocols described in the IEEE standard [1]. Attacker nodes alter the IEEE 802.11 DCF firmware to illicitly capture the channel via elevating the probability of the average number of packets transmitted successfully using up the bandwidth share of the innocent nodes that follow the protocol standards. We obtained the theoretical network throughput by solving two-dimensional Markov Chain model as described by Bianchi [2], and Liu and Saadawi [3] to determine the channel capacity. We validated the results obtained via the theoretical computations with the results obtained by OPNET simulator [4] to define the baseline for the average attainable throughput in the channel under standard conditions where all nodes follow the standards. The main goal of the DoS attacker is to prevent the innocent nodes from accessing the channel and by capturing the channel's bandwidth. In addition, the attacker strives to appear as an innocent node that follows the standards. The protocol resides in every node to enable each node to police other nodes in its immediate wireless coverage area. All innocent nodes are able to detect and identify the DoS attacker in its wireless coverage area. We applied the protocol to two Physical Layer technologies: Direct Sequence Spread Spectrum (DSSS) and Frequency Hopping Spread Spectrum (FHSS) and the results are presented to validate the algorithm.

  16. Van Hove singularities in the paramagnetic phase of the Hubbard model: DMFT study

    NASA Astrophysics Data System (ADS)

    Žitko, Rok; Bonča, Janez; Pruschke, Thomas

    2009-12-01

    Using the dynamical mean-field theory (DMFT) with the numerical renormalization-group impurity solver we study the paramagnetic phase of the Hubbard model with the density of states (DOS) corresponding to the three-dimensional (3D) cubic lattice and the two-dimensional (2D) square lattice, as well as a DOS with inverse square-root singularity. We show that the electron correlations rapidly smooth out the square-root van Hove singularities (kinks) in the spectral function for the 3D lattice and that the Mott metal-insulator transition (MIT) as well as the magnetic-field-induced MIT differ only little from the well-known results for the Bethe lattice. The consequences of the logarithmic singularity in the DOS for the 2D lattice are more dramatic. At half filling, the divergence pinned at the Fermi level is not washed out, only its integrated weight decreases as the interaction is increased. While the Mott transition is still of the usual kind, the magnetic-field-induced MIT falls into a different universality class as there is no field-induced localization of quasiparticles. In the case of a power-law singularity in the DOS at the Fermi level, the power-law singularity persists in the presence of interaction, albeit with a different exponent, and the effective impurity model in the DMFT turns out to be a pseudogap Anderson impurity model with a hybridization function which vanishes at the Fermi level. The system is then a generalized Fermi liquid. At finite doping, regular Fermi-liquid behavior is recovered.

  17. Superfluid density of states and pseudogap phenomenon in the BCS-BEC crossover regime of a superfluid Fermi gas

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Watanabe, Ryota; Tsuchiya, Shunji; CREST

    2010-10-15

    We investigate single-particle excitations and strong-coupling effects in the BCS-BEC crossover regime of a superfluid Fermi gas. Including phase and amplitude fluctuations of the superfluid order parameter within a T-matrix theory, we calculate the superfluid density of states (DOS), as well as single-particle spectral weight, over the entire BCS-BEC crossover region below the superfluid transition temperature T{sub c}. We clarify how the pseudogap in the normal state evolves into the superfluid gap, as one passes through T{sub c}. While the pseudogap in DOS continuously evolves into the superfluid gap in the weak-coupling BCS regime, the superfluid gap in the crossovermore » region is shown to appear in DOS after the pseudogap disappears below T{sub c}. In the phase diagram with respect to the temperature and interaction strength, we determine the region where strong pairing fluctuations dominate over single-particle properties of the system. Our results would be useful for the study of strong-coupling phenomena in the BCS-BEC crossover regime of a superfluid Fermi gas.« less

  18. Femtosecond excitation tuning and site energy memory of population transfer in poly(p-phenylenevinylene): Gated luminescence experiments and simulation

    NASA Astrophysics Data System (ADS)

    Sperling, J.; Milota, F.; Tortschanoff, A.; Warmuth, Ch.; Mollay, B.; Bässler, H.; Kauffmann, H. F.

    2002-12-01

    We present a comprehensive experimental and computational study on fs-relaxational dynamics of optical excitations in the conjugated polymer poly(p-phenylenevinylene) (PPV) under selective excitation tuning conditions into the long-wavelength, low-vibrational S1ν=0-density-of-states (DOS). The dependence of single-wavelength luminescence kinetics and time-windowed spectral transients on distinct, initial excitation boundaries at 1.4 K and at room temperature was measured applying the luminescence up-conversion technique. The typical energy-dispersive intra-DOS energy transfer was simulated by a combination of static Monte Carlo method with a dynamical algorithm for solving the energy-space transport Master-Equation in population-space. For various, selective excitations that give rise to specific S1-population distributions in distinct spatial and energetic subspaces inside the DOS, simulations confirm the experimental results and show that the subsequent, energy-dissipative, multilevel relaxation is hierarchically constrained, and reveals a pronounced site-energy memory effect with a migration-threshold, characteristic of the (dressed) excitation dynamics in the disordered PPV many-body system.

  19. Theoretical Study of α-V2O5 -Based Double-Wall Nanotubes.

    PubMed

    Porsev, Vitaly V; Bandura, Andrei V; Evarestov, Robert A

    2015-10-05

    First-principles calculations of the atomic and electronic structure of double-wall nanotubes (DWNTs) of α-V2 O5 are performed. Relaxation of the DWNT structure leads to the formation of two types of local regions: 1) bulk-type regions and 2) puckering regions. Calculated total density of states (DOS) of DWNTs considerably differ from that of single-wall nanotubes and the single layer, as well as from the DOS of the bulk and double layer. Small shoulders that appear on edges of valence and conduction bands result in a considerable decrease in the band gaps of the DWNTs (up to 1 eV relative to the single-layer gaps). The main reason for this effect is the shift of the inner- and outer-wall DOS in opposite directions on the energetic scale. The electron density corresponding to shoulders at the conduction-band edges is localized on vanadium atoms of the bulk-type regions, whereas the electron density corresponding to shoulders at the valence-band edges belongs to oxygen atoms of both regions. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. A LDA + U study of the photoemission spectra of the double hexagonal close packed phases of Am and Cm

    NASA Astrophysics Data System (ADS)

    Islam, M. Fhokrul; Ray, Asok K.

    2010-05-01

    We have investigated the photoemission spectra and other electronic structure properties such as equilibrium volume and bulk modulus of double hexagonal close packed (dhcp) americium and the density of states (DOS) and magnetic properties of dhcp curium using the LDA+U method. Our calculations show that spin polarized americium is energetically favorable but spin degenerate configuration produces experimental quantities significantly better than those calculated using the spin polarized configuration. The density of states calculated using LDA+U with both non-magnetic and spin polarized configurations is compared and the non-magnetic DOS is shown to be in good agreement with experimental photoemission spectra when U=4.5 eV. In spin polarized case, the onsite interaction parameter, U, is observed to increase the splitting between occupied and unoccupied bands by enhancing the Stoner parameter. The DOS of both non-magnetic americium and anti-ferromagnetic curium are shown to be in good agreement with that calculated using dynamical mean field theory for these two heavy actinides. For curium exchange interaction appears to play a dominant role in magnetic stability.

  1. Increased Diversity of Libraries from Libraries: Chemoinformatic Analysis of Bis-Diazacyclic Libraries

    PubMed Central

    López-Vallejo, Fabian; Nefzi, Adel; Bender, Andreas; Owen, John R.; Nabney, Ian T.; Houghten, Richard A.; Medina-Franco, Jose L.

    2011-01-01

    Combinatorial libraries continue to play a key role in drug discovery. To increase structural diversity, several experimental methods have been developed. However, limited efforts have been performed so far to quantify the diversity of the broadly used diversity-oriented synthetic (DOS) libraries. Herein we report a comprehensive characterization of 15 bis-diazacyclic combinatorial libraries obtained through libraries from libraries, which is a DOS approach. Using MACCS keys, radial and different pharmacophoric fingerprints as well as six molecular properties, it was demonstrated the increased structural and property diversity of the libraries from libraries over the individual libraries. Comparison of the libraries to existing drugs, NCI Diversity and the Molecular Libraries Small Molecule Repository revealed the structural uniqueness of the combinatorial libraries (mean similarity < 0.5 for any fingerprint representation). In particular, bis-cyclic thiourea libraries were the most structurally dissimilar to drugs retaining drug-like character in property space. This study represents the first comprehensive quantification of the diversity of libraries from libraries providing a solid quantitative approach to compare and contrast the diversity of DOS libraries with existing drugs or any other compound collection. PMID:21294850

  2. Analysis of optical and electronic properties of MoS2 for optoelectronics and FET applications

    NASA Astrophysics Data System (ADS)

    Ullah, Muhammad S.; Yousuf, Abdul Hamid Bin; Es-Sakhi, Azzedin D.; Chowdhury, Masud H.

    2018-04-01

    Molybdenum disulfide (MoS2) is considered as a promising alternative to conventional semiconductor materials that used in the IC industry because of its novel properties. In this paper, we explore the optical and electronic properties of MoS2 for photodetector and transistors applications. This simulation is done using `DFT materials properties simulator'. Our findings show that mono- and multi-layer MoS2 is suitable for conventional and tunnel FET applications due to direct and indirect band-gap respectively. The bulk MoS2 crystal, which are composed of stacked layers have indirect bandgap and mono-layer MoS2 crystal form direct bandgap at the K-point of Brillouin zone. Indirect bandgap of bulk MoS2 crystal implies that phonons need to be involved in band-to-band tunneling (BTBT) process. Degenerately doped semiconductor, which is basically spinning the Fermi level, changing the DOS profile, and thinning the indirect bandgap that allow tunneling from valence band to conduction band. The optical properties of MoS2 is explored in terms of Absorption coefficient, extinction coefficient and refractive index. Our results shows that a MoS2 based photodetector can be fabricate to detect light in the visible range (below 500nm). It is also observed that the MoS2 is most sensitive for the light of wavelength 450nm.

  3. Measuring the quality of life in hypertension according to Item Response Theory.

    PubMed

    Borges, José Wicto Pereira; Moreira, Thereza Maria Magalhães; Schmitt, Jeovani; Andrade, Dalton Francisco de; Barbetta, Pedro Alberto; Souza, Ana Célia Caetano de; Lima, Daniele Braz da Silva; Carvalho, Irialda Saboia

    2017-05-04

    To analyze the Miniquestionário de Qualidade de Vida em Hipertensão Arterial (MINICHAL - Mini-questionnaire of Quality of Life in Hypertension) using the Item Response Theory. This is an analytical study conducted with 712 persons with hypertension treated in thirteen primary health care units of Fortaleza, State of Ceará, Brazil, in 2015. The steps of the analysis by the Item Response Theory were: evaluation of dimensionality, estimation of parameters of items, and construction of scale. The study of dimensionality was carried out on the polychoric correlation matrix and confirmatory factor analysis. To estimate the item parameters, we used the Gradual Response Model of Samejima. The analyses were conducted using the free software R with the aid of psych and mirt. The analysis has allowed the visualization of item parameters and their individual contributions in the measurement of the latent trait, generating more information and allowing the construction of a scale with an interpretative model that demonstrates the evolution of the worsening of the quality of life in five levels. Regarding the item parameters, the items related to the somatic state have had a good performance, as they have presented better power to discriminate individuals with worse quality of life. The items related to mental state have been those which contributed with less psychometric data in the MINICHAL. We conclude that the instrument is suitable for the identification of the worsening of the quality of life in hypertension. The analysis of the MINICHAL using the Item Response Theory has allowed us to identify new sides of this instrument that have not yet been addressed in previous studies. Analisar o Miniquestionário de Qualidade de Vida em Hipertensão Arterial (MINICHAL) por meio da Teoria da Resposta ao Item. Estudo analítico realizado com 712 pessoas com hipertensão arterial atendidas em 13 unidades de atenção primária em saúde de Fortaleza, CE, em 2015. As etapas da análise pela Teoria da Resposta ao Item foram: avaliação da dimensionalidade, estimação dos parâmetros dos itens e construção da escala. O estudo da dimensionalidade foi realizado sobre a matriz de correlação policórica e análise fatorial confirmatória. Para a estimação dos parâmetros dos itens, foi utilizado o Modelo de Resposta Gradual de Samejima. As análises foram conduzidas no software livre R com o auxílio dos pacotes psych e mirt. A análise permitiu a visualização dos parâmetros dos itens e suas contribuições individuais na mensuração do traço latente, gerando mais informação, permitindo a construção de uma escala com um modelo interpretativo que demonstra a evolução da piora da qualidade de vida em cinco níveis. Quanto aos parâmetros dos itens, houve bom desempenho daqueles referentes ao estado somático, pois apresentaram melhor poder de discriminar os indivíduos com pior qualidade de vida. Os itens relacionados ao estado mental foram os que contribuíram com menor quantidade de informação psicométrica no MINICHAL. Conclui-se que o instrumento é indicado para a identificação da deterioração da qualidade de vida em hipertensão arterial. A análise do MINICHAL pela Teoria da Resposta ao Item permitiu identificar novas facetas desse instrumento ainda não abordadas em estudos anteriores.

  4. Patient survival and risk of death after prostate cancer treatment in the Brazilian Unified Health System.

    PubMed

    Braga, Sonia Faria Mendes; Souza, Mirian Carvalho de; Oliveira, Raphael Romie de; Andrade, Eli Iola Gurgel; Acurcio, Francisco de Assis; Cherchiglia, Mariangela Leal

    2017-05-15

    Analyze the probability of specific survival and factors associated with the risk of death of patients with prostate cancer who received outpatient cancer treatment in the Brazilian Unified Health System, Brazil. Retrospective cohort study using the National Database of Oncology, developed through the deterministic-probabilistic pairing of health information systems: outpatient (SIA), hospital (SIH) and mortality (SIM). The probability of overall and specific survival was estimated by the time elapsed between the date of the first ambulatory treatment, from 2002 to 2003, until the patient's death or the end of the study. Fine and Gray's model of competing-risks regression was adjusted according to the variables: age of diagnostic, region of residence, tumor clinical staging, type of outpatient cancer treatment and hospitalization in the assessment of factors associated with risk of patient death. Of 16,280 patients studied, the average age was 70 years, approximately 25% died due to prostate cancer and 20% for other causes. The probability of overall survival was 0.50 (95%CI 0.49-0.52) and the specific was 0.70 (95%CI 0.69-0.71). The factors associated with the risk of patient death were: stage III (HR = 1.66; 95%CI 1.39-1.99) and stage IV (HR = 3.49; 95%CI 2.91-4.18), chemotherapy (HR = 2.34; 95%CI 1.76-3.11) and hospitalization (HR = 1.6; 95%CI 1.55-1.79). The late diagnosis of the tumor, palliative treatments, and worse medical condition were factors related to the worst survival and increased risk of death from prostate cancer patients in Brazil. Analisar a probabilidade de sobrevida específica e os fatores associados ao risco de óbito dos pacientes com câncer de próstata, que receberam tratamento oncológico ambulatorial no SUS, Brasil. Estudo de coorte retrospectivo utilizando a Base Nacional em Oncologia, desenvolvida por meio de pareamento determinístico-probabilístico dos sistemas de informação de saúde: ambulatorial (SIA), hospitalar (SIH) e de mortalidade (SIM). A probabilidade de sobrevida global e específica foi estimada pelo tempo decorrido entre a data do primeiro tratamento ambulatorial, entre 2002 e 2003, até o óbito dos pacientes ou fim do estudo. O modelo de regressão de riscos competitivos de Fine e Gray foi ajustado segundo as variáveis: idade ao diagnóstico, região de residência, estadiamento clínico do tumor, tipo de tratamento oncológico ambulatorial e internação na avaliação dos fatores associados ao risco de óbito dos pacientes. Dos 16.280 pacientes estudados, a idade média foi de 70 anos, cerca de 25% foi a óbito devido ao câncer de próstata e 20% por outras causas. A probabilidade de sobrevida global foi de 0,50 (IC95% 0,49-0,52) e a específica 0,70 (IC95% 0,69-0,71) . Os fatores associados ao risco de óbito dos pacientes foram: estádio III (HR = 1,66; IC95% 1,39-1,99) e estágio IV (HR = 3,49; IC95% 2,91-4,18), tratamento quimioterápico (HR = 2,34; IC95% 1,76-3,11) e internação (HR = 1,6; IC95% 1,55-1,79). O diagnóstico tardio do tumor, tratamentos não curativos e pior condição clínica foram fatores relacionados à pior sobrevida e ao maior risco de óbito dos pacientes com câncer próstata no Brasil.

  5. The essence of care in health vulnerability: a Heideggerian construction.

    PubMed

    Cestari, Virna Ribeiro Feitosa; Moreira, Thereza Maria Magalhães; Pessoa, Vera Lúcia Mendes de Paula; Florêncio, Raquel Sampaio; Silva, Maria Rocineide Ferreira da; Torres, Raimundo Augusto Martins

    2017-01-01

    Reflect on the essence of care in health vulnerability from the phenomenological perspective of Martin Heidegger. Theoretical-reflexive study, anchored in three essential parts: 1) Care in Heidegger; 2) The essence of care in health vulnerability; And 3) Nursing care actions on health vulnerability. Vulnerability must be recognized as an indelible trait of the human condition and has its constituents in the human being, co-presence and care. Caring is an interactive process that reveals itself in the relationship with the other. Respecting the integrity of the Being in vulnerability must be a priority in nursing care, through behaviors that privilege the Being. Understanding ontological care and its relation to vulnerability under Heidegger's phenomenological view allowed us to uncover the facets of care in health vulnerability by adding to the nursing knowledge body a comprehensive and reflective perspective. Refletir sobre a essência do cuidado na vulnerabilidade em saúde sob a perspectiva fenomenológica de Martin Heidegger. Estudo teórico-reflexivo, ancorado em três partes essenciais: 1) O cuidado em Heidegger; 2) A essência do cuidado na vulnerabilidade em saúde; e 3) As ações do cuidar em enfermagem na vulnerabilidade em saúde. A vulnerabilidade deve ser reconhecida como traço indelével da condição humana e tem seus constituintes na pessoa humana, co-presenças e cuidado. O cuidar é um processo interativo que se desvela na relação com o outro. Respeitar a integridade do Ser em vulnerabilidade deve ser prioridade no cuidar em enfermagem, por meio de comportamentos que privilegiem o Ser. Compreender ontologicamente o cuidado e a sua relação com a vulnerabilidade sob o olhar fenomenológico de Heidegger permitiu desvelar as facetas do cuidado na vulnerabilidade em saúde, agregando ao corpo de conhecimento da Enfermagem uma perspectiva compreensiva e reflexiva.

  6. A tight binding model study of tunneling conductance spectra of spin and orbitally ordered CMR manganites

    NASA Astrophysics Data System (ADS)

    Panda, Saswati; Sahoo, D. D.; Rout, G. C.

    2018-04-01

    We report here a tight binding model for colossal magnetoresistive (CMR) manganites to study the pseudo gap (PG) behavior near Fermi level. In the Kubo-Ohata type DE model, we consider first and second nearest neighbor interactions for transverse spin fluctuations in core band and hopping integrals in conduction band, in the presence of static band Jahn-Teller distortion. The model Hamiltonian is solved using Zubarev's Green's function technique. The electron density of states (DOS) is found out from the Green's functions. We observe clear PG near Fermi level in the electron DOS.

  7. Studies of Brazilian meteorites. III - Origin and history of the Angra dos Reis achondrite

    NASA Technical Reports Server (NTRS)

    Prinz, M.; Keil, K.; Hlava, P. F.; Berkley, J. L.; Gomes, C. B.; Curvello, W. S.

    1977-01-01

    The mineral composition of the Angra dos Reis meteorite, which fell in 1869, is described. This achondrite contains phases reported in a meteorite for the first time. Petrofabric analysis shows that fassaite has a preferred orientation and lineation, which is interpreted as being due to cumulus processes, possibly the effect of post-depositional magmatic current flow or laminar flow of a crystalline mush. The mineral chemistry indicates crystallization from a highly silica-undersaturated melt at low pressure. Several aspects of the mineral composition are discussed with reference to the implications of crystallization conditions.

  8. Rare earth elements in Angra dos Reis and Lewis Cliff 86010, two meteorites with similar but distinct magma evolutions

    NASA Technical Reports Server (NTRS)

    Crozaz, Ghislaine; Mckay, Gordon

    1990-01-01

    Data are presented on ion microprobe measurements of REE and selected trace element abundances in individual grains of merrillite, fassaite, olivine, kirschsteinite, and plagioclase of Lewis Cliff 86010 (LEW 86010) meteorite and in merrillite and fassaite grains of Angra dos Reis (ADOR). Results show a close relationship between the two meteorites and support a magmatic origin for LEW 86010. However, the measurements indicate that, despite numerous common characteristics, the two meteorites must have been produced in separate magmatic events involving similar but distinct processes and parent melts.

  9. Assessment of the effect of No Stay, Bent Stay or Straight Stay when the Clothe the Soldier Rucksack is Worn with the Fragmentation Vest

    DTIC Science & Technology

    2006-02-01

    effets de différents renforts de sac à dos (renforts droits, renforts courbés et aucun renfort) sur la...supérieures au seuil de tolérance de la peau et des muscles sous-jacents, et elles pourraient causer des lésions sur la peau et des ecchymoses. Assessment...présente évaluation portait sur cette pratique et visait à déterminer les effets de différents renforts de sac à dos (renforts droits, renforts courbés

  10. Effectiveness of teaching strategies on the development of critical thinking in undergraduate nursing students: a meta-analysis.

    PubMed

    Oliveira, Larissa Bertacchini de; Díaz, Leidy Johanna Rueda; Carbogim, Fábio da Costa; Rodrigues, Adriano Rogério Baldacin; Püschel, Vilanice Alves de Araújo

    2016-04-01

    To evaluate the effectiveness of teaching strategies used for development of critical thinking (CT) in undergraduate nursing students. Systematic review with meta-analysis based on the recommendations of the Joanna Briggs Institute . Searches were conducted in the following databases: PubMed, CINAHL, EMBASE, Web of Science, SCOPUS, LILACS, Cochrane CENTRAL, PsycINFO, ERIC, and a database of theses from four continents. The initial selection and evaluation of studies and assessment of methodological quality was performed by two reviewers independently. Twelve randomized clinical trials were included in the study. In the meta-analysis of the four studies included that evaluated the strategy of problem-based learning (PBL), compared to lectures, the effectiveness of PBL was demonstrated with statistical significance (SMD = 0.21 and 95% CI = 0.01 to 0.42; p = 0.0434) for the development of CT in undergraduate nursing students, and the studies were homogeneous (chi-square = 6.10, p = 0.106). The effectiveness of PBL was demonstrated in the increase of overall CT scores. Further studies need to be conducted in order to develop, implement and evaluate teaching strategies that are guided in high methodological rigor, and supported in theoretical models of teaching and learning. Avaliar a efetividade das estratégias de ensino utilizadas para o desenvolvimento do pensamento crítico (PC) em estudantes de graduação em Enfermagem. Revisão sistemática com metanálise baseada nas recomendações do Joanna Briggs Institute. A busca foi realizada nas bases de dados PubMed, CINAHL, EMBASE, Web of Science, SCOPUS, LILACS, Cochrane CENTRAL, PsycINFO e ERIC e de banco de teses dos quatro continentes. A seleção e avaliação inicial dos estudos e a avaliação da qualidade metodológica foi realizada por dois revisores de forma independente. Incluídos 12 ensaios clínico randomizados. Na metanálise, dos quatro estudos incluídos que avaliaram a estratégia do Problem Based Learning (PBL), comparada a palestras, foi demonstrada a efetividade do PBL, estatisticamente significativa (SMD=0,21 e 95% IC=0,01-0,42; p=0,0434) para o desenvolvimento do PC em estudantes de graduação em Enfermagem e os estudos eram homogêneos (Qui-quadrado=6,10, p=0,106). Foi demonstrada a efetividade do PBL no aumento dos escores de PC global. Novos estudos precisam ser feitos com o objetivo de desenvolver, implementar e avaliar estratégias de ensino, que sejam pautadas em alto rigor metodológico e amparadas em modelos teóricos de ensino-aprendizagem.

  11. The collagen, fibrinogen and thrombin biological adhesive is effective in treating experimental liver injuries.

    PubMed

    Oliveira, Frederico Michelino de; Carvalho, Marcus Vinícius H de; Marchi, Evaldo; Pinto, Clóvis Antônio Lopes

    2016-01-01

    to evaluate the effectiveness of an collagen-based adhesive associated with fibrinogen and thrombin in experimental liver injuries in rats. we randomly divided 30 Wistar rats into three groups: A, B and C. All underwent a standard liver traumatic injury. In group A, the lesion was treated with the adhesive; in group B, with conventional, absorbable suture; group C received no treatment. We analyzed the time of hemostasis, mortality, occurrence of adhesions and any histological changes. there was no statistical difference in relation to mortality (p=0.5820). The adhesive treated group showed the lowest hemostasis times (p=0.0573, odds ratio 13.5) and lower incidence of adhesions (p=0.0119). The histological alterations of the Groups A and B were similar, with foreign body granuloma formation separating the adhesive material and the hepatic stroma suture. the collagen adhesive associated with fibrinogen and thrombin was effective in treating experimental hepatic injury, providing a lower incidence of adhesions between the liver and surrounding structures. avaliar a eficácia de um adesivo a base de colágeno associado ao fibrinogênio e trombina, no trauma hepático experimental em ratos. toram incluídos no estudo 30 ratos Wistar, igualmente divididos aleatoriamente em três grupos: A, B e C. Todos foram submetidos à lesão traumática hepática padronizada. No grupo A, a lesão foi tratada com o adesivo, no grupo B, com sutura convencional com fio absorvível, e no grupo C, não houve tratamento da lesão. Foram analisados o tempo de hemostasia, mortalidade, ocorrência de aderências e eventuais alterações histológicas. os resultados mostraram que não houve diferença estatística em relação à mortalidade (p=0,5820). O grupo tratado com adesivo apresentou os menores tempos de hemostasia (p=0,0573 e odds ratio 13,5) e menor ocorrência de aderências (p=0,0119). Microscopicamente as alterações histológicas dos grupos A e B foram semelhantes, com a formação de granuloma de corpo estranho separando o material do adesivo e do fio de sutura do estroma hepático. o adesivo de colágeno associado ao fibrinogênio e trombina foi eficaz no tratamento do trauma hepático experimental, proporcionado menor ocorrência de aderências entre o fígado e as estruturas vizinhas.

  12. [Not Available].

    PubMed

    Martínez-Lozano Aranaga, Fátima; Palacios Vales, Paula; Serrano Navarro, Juana María; Caballero Requejo, Carmen; Gómez Ramos, María Jesús; Sánchez Álvarez, Carmen

    2016-06-30

    Introducción: la composición lipídica de las fórmulas de nutrición parenteral (NP) se postula como posible factor de evolución clínica.Objetivo: evaluar las diferencias en eficacia y seguridad de dos emulsiones lipídicas en NP.Material y métodos: estudio clínico prospectivo de pacientes posquirúrgicos sometidos a NP durante más de 7 días en un periodo de 2 años. Se administraron de forma indistinta 2 tipos de emulsiones lipídicas: enriquecida con ácidos grasos omega 3 (SMOFlipid Fresenius Kabi®) o con ácido oleico omega 9 (Clinoleic Baxter®). Se analizaron variables epidemiológicas, analíticas, complicaciones infecciosas y mortalidad.Resultados: se estudió un total de 154 pacientes con edad media de 64,36 ± 13,73 años, de los que 95 eran hombres (61%), 78 (51%) recibieron SMOFlipid® y 76 (49%) Clinoleic®. La estancia media fue de 16,91 ± 4,23 días, la duración de la NP 9,68 ± 3,25 días y la mortalidad del 11%. Se diagnosticaron 58 (37%) infecciones. No existieron diferencias significativas en cuanto a los parámetros analíticos lipídicos, hepáticos o nutricionales (medidos al inicio y al 7.º día) ni en su evolución (estancia media, complicaciones infecciosas ni mortalidad) entre los dos grupos de pacientes.Conclusión: los pacientes sometidos a NP presentan similares características evolutivas con independencia de la emulsión lipídica utilizada. La bibliografía actual apunta a un beneficio de la disminución del aporte de ácidos grasos omega 9, pero no se han encontrado diferencias significativas entre las fórmulas comparadas.

  13. Local Structure Analysis and Interface Layer Effect of Phase-Change Recording Material Using Actual Media

    NASA Astrophysics Data System (ADS)

    Nakai, Tsukasa; Yoshiki, Masahiko; Satoh, Yasuhiro; Ashida, Sumio

    2008-07-01

    The influences of the interface layer on crystal structure, the local atomic arrangement, and the electronic and chemical structure of a GeBiTe (GBT) phase-change recording material have been investigated using X-ray diffraction (XRD), X-ray absorption fine structure (XAFS), and hard X-ray photoelectron spectroscopy (HX-PES) methods using actual rewritable high-speed HD DVD media without special sample processing. XRD results showed that the crystal structure of laser-crystallized GBT alloy in the actual HD DVD media is the same as that of GeSbTe (GST) alloy, which has a NaCl-type structure. No differences between samples with and without interface layers were found. The lattice constant of GBT is larger than that of GST. Bi increases the lattice constant of GST with respect to the Bi substitution ratio of Sb. According to HX-PES, the DOS of in the recording film amorphous state with an interface layer is closer to that of the crystalline state than the recording film without an interface layer. From XAFS results, clear differences between amorphous (Amo.) and crystalline states (Cry.) were observed. The interatomic distance of amorphous recording material is independent of the existence of an interface layer. On the other hand, the coordination number varied slightly due to the presence of the interface layer. Therefore, the electronic state of the recording layer changes because of the interface layer, although the local structure changes only slightly except for the coordination number. Combining these results, we conclude that the interface layer changes the electronic state of the recording layer and promotes crystallization, but only affects the local structure of the atomic arrangement slightly.

  14. Thermoelectric transport properties of high mobility organic semiconductors

    NASA Astrophysics Data System (ADS)

    Venkateshvaran, Deepak; Broch, Katharina; Warwick, Chris N.; Sirringhaus, Henning

    2016-09-01

    Transport in organic semiconductors has traditionally been investigated using measurements of the temperature and gate voltage dependent mobility of charge carriers within the channel of organic field-effect transistors (OFETs). In such measurements, the behavior of charge carrier mobility with temperature and gate voltage, studied together with carrier activation energies, provide a metric to quantify the extent of disorder within these van der Waals bonded materials. In addition to the mobility and activation energy, another potent but often-overlooked transport coefficient useful in understanding disorder is the Seebeck coefficient (also known as thermoelectric power). Fundamentally, the Seebeck coefficient represents the entropy per charge carrier in the solid state, and thus proves powerful in distinguishing materials in which charge carriers move freely from those where a high degree of disorder causes the induced carriers to remain trapped. This paper briefly covers the recent highlights in the field of organic thermoelectrics, showing how significant strides have been made both from an applied standpoint as well as from a viewpoint of fundamental thermoelectric transport physics. It shall be illustrated how thermoelectric transport parameters in organic semiconductors can be tuned over a significant range, and how this tunability facilitates an enhanced performance for heat-to-electricity conversion as well as quantifies energetic disorder and the nature of the density of states (DOS). The work of the authors shall be spotlighted in this context, illustrating how Seebeck coefficient measurements in the polymer indacenodithiophene-co-benzothiadiazole (IDTBT) known for its ultra-low degree of torsion within the polymer backbone, has a trend consistent with low disorder. 1 Finally, using examples of the small molecules C8-BTBT and C10-DNTT, it shall be discussed how the Seebeck coefficient can aid the estimation of the density and distribution of trap states within these materials. 2, 3

  15. Treatment of Solid Rocket Motors that Complies with Established Protocols to Ensure Planetary Protection

    NASA Technical Reports Server (NTRS)

    Stefanski, Philip L.; Soler-Luna, Adrian

    2017-01-01

    This presentation discusses recent work being conducted by the National Aeronautics and Space Administration (NASA) at Marshall Space Flight Center (MSFC) to evaluate various methods that could be employed to provide for planetary protection of those solar system bodies that are candidates for extraterrestrial life, thus preventing contamination of such bodies. MSFC is presently involved in the development phase of the Europa Lander De-Orbital Stage (DOS) braking motor. In order to prevent bio-contamination of this Jovian satellite, three paths are currently being considered. The first is (1) Bio-Reduction of those microscopic organisms in or on the vehicle (in this case a solid rocket motor (SRM)) that might otherwise be transported during the mission. Possible methods being investigated include heat sterilization, application or incorporation of biocide materials, and irradiation. While each method can be made to work, effects on the SRM's components (propellant, liner, insulation, etc.) could well prove deleterious. A second path would be use of (2) Bio-Barrier material(s). So long as such barrier(s) can maintain their integrity, planetary protection should be afforded. Under the harsh conditions encountered during extended spaceflight (vacuum, temperature extremes, radiation), however, such barrier(s) could well experience a breach. Finally, a third path would be to perform (3) Pyrotechnic Sterilization of the SRM during its end-of-mission phase. Multiple pyrotechnic units would be triggered to ensure activation of such an event and provide for a final sterilization before vehicle impact. In light of Europa's stringent bio-reduction targets, the final and best choice to minimize risk will probably be some combination of the above.

  16. Association between diabetes and tuberculosis: case-control study.

    PubMed

    Pereira, Susan Martins; Araújo, Gleide Santos de; Santos, Carlos Antônio de Souza Teles; Oliveira, Maeli Gomes de; Barreto, Maurício Lima

    2016-12-22

    To test the association between diabetes and tuberculosis. It is a case-control study, matched by age and sex. We included 323 new cases of tuberculosis with positive results for bacilloscopy. The controls were 323 respiratory symptomatic patients with negative bacilloscopy, from the same health services, such as: ambulatory cases from three referral hospitals and six basic health units responsible for the notifications of new cases of tuberculosis in Salvador, Bahia. Data collection occurred between 2008 and 2010. The instruments used were structured interview, including clinical data, capillary blood glucose (during fasting or postprandial), and the CAGE questionnaire for screening of abusive consumption of alcohol. Descriptive, exploratory, and multivariate analysis was performed using conditional logistic regression. The average age of the cases was 38.5 (SD = 14.2) years and of the controls, 38.5 (SD = 14.3) years. Among cases and controls, most subjects (61%) were male. In univariate analysis we found association between the occurrence of diabetes and tuberculosis (OR = 2.37; 95%CI 1.04-5.42), which remained statistically significant after adjustment for potential confounders (OR = 3.12; 95%CI 1.12-7.94). The association between diabetes and tuberculosis can hinder the control of tuberculosis, contributing to the maintainance of the disease burden. The situation demands increasing early detection of diabetes among people with tuberculosis, in an attempt to improve disease control strategies. Testar a associação entre diabetes e tuberculose. Trata-se de estudo caso-controle, pareado por idade e sexo. Foram incluídos 323 casos novos de tuberculose com resultados positivos à baciloscopia. Os controles foram 323 sintomáticos respiratórios com baciloscopia negativa, oriundos dos mesmos serviços de saúde dos casos: ambulatórios de três hospitais de referência e seis unidades básicas de saúde responsáveis pelas notificações dos casos novos de tuberculose em Salvador, Bahia. A coleta de dados ocorreu entre 2008 e 2010. Os instrumentos utilizados foram entrevista estruturada, incluindo dados clínicos, glicemia capilar (em jejum ou pós-prandial) e o questionário CAGE para triagem de consumo abusivo de álcool. Foi realizada análise descritiva, exploratória e multivariada utilizando-se de regressão logística condicional. A média de idade dos casos foi 38,5 (DP = 14,2) anos e dos controles, 38,5 (DP = 14,3) anos. Tanto entre os casos quanto entre os controles, a maioria (61%) dos indivíduos era do sexo masculino. Na análise univariada, houve associação entre ocorrência de diabetes e de tuberculose (OR = 2,37; IC95% 1,04-5,42), que permaneceu estatisticamente significante após ajuste pelos potenciais confundidores (OR = 3,12; IC95% 1,12-7,94). A associação entre diabetes e tuberculose pode dificultar o controle da tuberculose, contribuindo para manutenção da elevada carga da doença. A situação demanda intensificação da detecção precoce de diabetes entre pessoas com tuberculose, na tentativa de maior efetividade das estratégias de controle da doença.

  17. A Utilização da Astronomia como Tema Interdisciplinar e Aplicações de Objetos de Aprendizagem

    NASA Astrophysics Data System (ADS)

    da Silva, L. A.; Voelzke, M. R.

    2008-09-01

    Este trabalho visa analisar a possibilidade de relacionar conteúdos aplicados no ensino fundamental e médio de forma interdisciplinar por intermédio da astronomia, com a intervenção de objetos de aprendizagem que possam integrar as disciplinas e a utilização de recursos tecnológicos. Em uma pesquisa prévia com 20 professores de uma escola estadual situada na cidade de Guarulhos foi observado que apenas 25% dos professores utilizam algum recurso tecnológico para o desenvolvimento de conteúdos pertinentes à sua disciplina, tais como sites e softwares educativos, sendo que a maioria absoluta continua ensinando apenas com livros didáticos. A maior parte dos professores apresenta dificuldades em trabalhar sua disciplina de forma interdisciplinar, ou seja, 75% dos professores preferem aplicar os conteúdos seguindo uma hierarquia linear de tópicos, evitando a discussão de temas que de alguma forma estão relacionados. A astronomia pode vir à fascinar o ser humano e despertar sua curiosidade promovendo um maior interesse no aprendizado, podendo favorecer análises interdisciplinares de forma lógica e objetiva, desta forma colocar a astronomia como tema motivador interdisciplinar, pode ser relevante no que se refere ao distanciamento da fragmentação dos conteúdos. No Estado de São Paulo, a implantação da proposta curricular no ensino fundamental e médio mostra claramente a inserção da astronomia na maior parte das séries, principalmente na 6ª série em que todo o bimestre se fala de astronomia.

  18. Aerobic exercise training promotes additional cardiac benefits better than resistance exercise training in postmenopausal rats with diabetes.

    PubMed

    Quinteiro, Hugo; Buzin, Morgana; Conti, Filipe Fernandes; Dias, Danielle da Silva; Figueroa, Diego; Llesuy, Susana; Irigoyen, Maria-Cláudia; Sanches, Iris Callado; De Angelis, Kátia

    2015-05-01

    The aim of this study was to evaluate the effects of aerobic exercise training or resistance exercise training on cardiac morphometric, functional, and oxidative stress parameters in rats with ovarian hormone deprivation and diabetes. Female Wistar rats (200-220 g) were divided into a sham-operated group (euglycemic sham-operated sedentary [ES]; n = 8) and three ovariectomized (bilateral removal of ovaries) and diabetic (streptozotocin 50 mg/kg IV) groups as follows: diabetic ovariectomized sedentary (DOS; n = 8), diabetic ovariectomized undergoing aerobic exercise training (DOTA; n = 8), and diabetic ovariectomized undergoing resistance exercise training (DOTR; n = 8). After 8 weeks of resistance (ladder) or aerobic (treadmill) exercise training, left ventricle function and morphometry were evaluated by echocardiography, whereas oxidative stress was evaluated at the left ventricle. The DOS group presented with increased left ventricle cavity in diastole and relative wall thickness (RWT), and these changes were attenuated in both DOTA and DOTR groups. Systolic and diastolic function was impaired in the DOS group compared with the ES group, and only the DOTA group was able to reverse this dysfunction. Lipoperoxidation and glutathione redox balance were improved in both trained groups compared with the DOS group. Glutathione peroxidase and superoxide dismutase were higher in the DOTA group than in the other studied groups. Correlations were observed between lipoperoxidation and left ventricle cavity in diastole (r = 0.55), between redox balance and RWT (r = 0.62), and between lipoperoxidation and RWT (r = -0.60). Aerobic exercise training and resistance exercise training promote attenuation of cardiac morphometric dysfunction associated with a reduction in oxidative stress in an experimental model of diabetes and menopause. However, only dynamic aerobic exercise training is able to attenuate systolic and diastolic dysfunction under this condition.

  19. A diversity-oriented synthesis strategy enabling the combinatorial-type variation of macrocyclic peptidomimetic scaffolds† †Electronic supplementary information (ESI) available: Experimental procedures, characterization data and details of the computational analyses. See DOI: 10.1039/c5ob00371g Click here for additional data file.

    PubMed Central

    Isidro-Llobet, Albert; Hadje Georgiou, Kathy; Galloway, Warren R. J. D.; Giacomini, Elisa; Hansen, Mette R.; Méndez-Abt, Gabriela; Tan, Yaw Sing; Carro, Laura; Sore, Hannah F.

    2015-01-01

    Macrocyclic peptidomimetics are associated with a broad range of biological activities. However, despite such potentially valuable properties, the macrocyclic peptidomimetic structural class is generally considered as being poorly explored within drug discovery. This has been attributed to the lack of general methods for producing collections of macrocyclic peptidomimetics with high levels of structural, and thus shape, diversity. In particular, there is a lack of scaffold diversity in current macrocyclic peptidomimetic libraries; indeed, the efficient construction of diverse molecular scaffolds presents a formidable general challenge to the synthetic chemist. Herein we describe a new, advanced strategy for the diversity-oriented synthesis (DOS) of macrocyclic peptidomimetics that enables the combinatorial variation of molecular scaffolds (core macrocyclic ring architectures). The generality and robustness of this DOS strategy is demonstrated by the step-efficient synthesis of a structurally diverse library of over 200 macrocyclic peptidomimetic compounds, each based around a distinct molecular scaffold and isolated in milligram quantities, from readily available building-blocks. To the best of our knowledge this represents an unprecedented level of scaffold diversity in a synthetically derived library of macrocyclic peptidomimetics. Cheminformatic analysis indicated that the library compounds access regions of chemical space that are distinct from those addressed by top-selling brand-name drugs and macrocyclic natural products, illustrating the value of our DOS approach to sample regions of chemical space underexploited in current drug discovery efforts. An analysis of three-dimensional molecular shapes illustrated that the DOS library has a relatively high level of shape diversity. PMID:25778821

  20. Simulações Numéricas de Rotação Nuclear Cometária

    NASA Astrophysics Data System (ADS)

    Voelzke, M. R.; Winter, O. C.

    1999-08-01

    Este trabalho apresenta os resultados iniciais de simulações numéricas da evolução rotacional, de um núcleo cometário não esférico, ao longo de uma passagem periélica, levando-se em conta os torques devido a existência dos jatos de poeira e de gás. Inicialmente os autores apresentam um modelo simples (primeira aproximação), com somente um único jato na extremidade do semi-eixo maior, para compreender a variação positiva ou negativa que estas forças não gravitacionais exercem sobre o período de rotação cometário. Posteriormente incrementa-se o número de jatos, os quais são distribuídos ao longo da superfície cometária, para observar-se a contribuição dos efeitos provenientes dos torques originários da liberação da poeira e gás cometários, que provavelmente violará a suposição da livre precessão. Os estados rotacionais, sob torques induzidos devido à sublimação, dependem fortemente da localização das áreas ativas do núcleo. Os cometas P/Schwassmann-Wachmann 1, P/Tempel 2, P/Forbes e C/Meunier-Dupouy serão observados fotometricamente, pelos autores, no Laboratório Nacional de Astrofísica (LNA) ao longo de algumas noites consecutivas em abril, junho e julho de 1999. Estas observações serão comparadas com as simulações numéricas de rotação cometária.

  1. 2.3 Å X-ray Structure of the Heme-Bound GAF Domain of Sensory Histidine Kinase DosT of Mycobacterium tuberculosis†

    PubMed Central

    Podust, Larissa M.; Ioanoviciu, Alexandra; Ortiz de Montellano, Paul R.

    2009-01-01

    Mycobacterium tuberculosis responds to the changes in environmental conditions through a two-component signaling system that detects reduced O2 tension and NO and CO exposures via the heme-binding GAF domains of two sensory histidine kinases, DosT and DevS, and the transcriptional regulator DosR. We report the first x-ray structure of the DosT heme-bound GAF domain (GAFDosT) in both oxy and deoxy forms determined to a resolution of 2.3 Å. In GAFDosT, heme binds in an orientation orthogonal to that in the PAS domains via a highly conserved motif including invariant H147 as a proximal heme axial ligand. On the distal side, invariant Y169 is in stacking interactions with the heme with its long axis parallel and the plane of the ring orthogonal to the heme plane. In one of the two protein monomers in an asymmetric unit, O2 binds as a second axial ligand to the heme iron, and is stabilized via an H-bond to the OH-group of Y169. The structure reveals two small tunnel-connected cavities and a pore on the protein surface that suggest a potential route for O2 access to the sensing pocket. The limited conformational differences observed between differently heme iron-ligated GAFDosT monomers in the asymmetric unit may result from crystal lattice limitations since atmospheric oxygen binding likely occurs in the crystal as a result of x-ray induced Fe3+ photoreduction during diffraction data collection. Determination of the GAFDosT structure sets up a framework in which to address ligand-recognition, discrimination, and signal propagation schemes in the heme-based GAF domains of biological sensors. PMID:18980385

  2. Age and isotopic relationships among the angrites Lewis Cliff 86010 and Angra dos Reis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lugmair, G.W.; Galer, S.J.G.

    1992-04-01

    Results of a wide-ranging isotopic investigation of the unique Antarctican angrite LEW-86010 (LEW) are presented, together with a reassessment of the type angrite Angra dos Reis (ADOR). The principal objectives of this study are to obtain precise radiometric ages, initial Sr isotopic compositions, and to search for the erstwhile presence of the short-lived nuclei {sup 146}Sm and {sup 26}Al via their daughter products. The isotopic compositions of Sm, U, Ca, and Ti were also measured. This allows a detailed appraisal to be made of the relations between, and the genealogy of, these two angrites.

  3. Electron tunneling in nanoscale electrodes for battery applications

    NASA Astrophysics Data System (ADS)

    Yamada, Hidenori; Narayanan, Rajaram; Bandaru, Prabhakar R.

    2018-03-01

    It is shown that the electrical current that may be obtained from a nanoscale electrochemical system is sensitive to the dimensionality of the electrode and the density of states (DOS). Considering the DOS of lower dimensional systems, such as two-dimensional graphene, one-dimensional nanotubes, or zero-dimensional quantum dots, yields a distinct variation of the current-voltage characteristics. Such aspects go beyond conventional Arrhenius theory based kinetics which are often used in experimental interpretation. The obtained insights may be adapted to other devices, such as solid-state batteries. It is also indicated that electron transport in such devices may be considered through electron tunneling.

  4. Self-enforcing Private Inference Control

    NASA Astrophysics Data System (ADS)

    Yang, Yanjiang; Li, Yingjiu; Weng, Jian; Zhou, Jianying; Bao, Feng

    Private inference control enables simultaneous enforcement of inference control and protection of users' query privacy. Private inference control is a useful tool for database applications, especially when users are increasingly concerned about individual privacy nowadays. However, protection of query privacy on top of inference control is a double-edged sword: without letting the database server know the content of user queries, users can easily launch DoS attacks. To assuage DoS attacks in private inference control, we propose the concept of self-enforcing private inference control, whose intuition is to force users to only make inference-free queries by enforcing inference control themselves; otherwise, penalty will inflict upon the violating users.

  5. Development of a prototype commonality analysis tool for use in space programs

    NASA Technical Reports Server (NTRS)

    Yeager, Dorian P.

    1988-01-01

    A software tool to aid in performing commonality analyses, called Commonality Analysis Problem Solver (CAPS), was designed, and a prototype version (CAPS 1.0) was implemented and tested. The CAPS 1.0 runs in an MS-DOS or IBM PC-DOS environment. The CAPS is designed around a simple input language which provides a natural syntax for the description of feasibility constraints. It provides its users with the ability to load a database representing a set of design items, describe the feasibility constraints on items in that database, and do a comprehensive cost analysis to find the most economical substitution pattern.

  6. Study of distorted octahedral structure in 3d transition metal complexes using XAFS

    NASA Astrophysics Data System (ADS)

    Gaur, A.; Nitin Nair, N.; Shrivastava, B. D.; Das, B. K.; Chakrabortty, Monideepa; Jha, S. N.; Bhattacharyya, D.

    2018-01-01

    Distortion in octahedral structure of 3d transition metal complexes (Mn, Fe, Co, Ni, Cu, Zn) has been studied using XAFS showing divergent nature of Cu complex. EXAFS analysis showed elongated metal-oxygen bonds for Cu complex leading to more distorted structure. Derivative XANES spectrum at Cu K-edge exhibits splitting of main edge which is correlated to elongated Cu-O bond length. Using these coordination geometry around metal centers, theoretical XANES spectra have been generated and features observed have been correlated to the corresponding metals p-DOS. It has been shown that distorted octahedral field in Cu complex is responsible for splitting of p-DOS.

  7. Development of a Dynamic Biomechanical Model for Load Carriage: Phase IV Part C1: Assessment of Pressure Measurement Systems on Flat Surfaces for use in Human Load Carriage

    DTIC Science & Technology

    2005-08-01

    iv Sommaire Les études sur les effets de la pression de contact produite par une charge d’un sac à dos sont essentielles, étant...mobilité des soldats et amenuiser leur capacité de combat. Afin de mieux comprendre les effets de la pression d’un sac à dos sur le confort et la... de mesure de pression qui pourraient être utilisés pour établir les valeurs de tolérance de la peau aux pressions durant le transport d’une charge

  8. Sensor de orvalho/chuva aplicado à operação de telescópios

    NASA Astrophysics Data System (ADS)

    Raffaelli, J. C.; Neres, N. L.; Strauss, C.

    2003-08-01

    Foi desenvolvida uma estação meteorológica para o telescópio robótico Obelix do Observatório Abrahão de Moraes que inclui sensores de temperatura e umidade, além de um inédito sensor de orvalho e chuva que comanda o fechamento automático da cúpula caso haja perigo de condensação. Este sensor é composto de uma malha de segmentos metálicos próximos e detecta o aumento da condutividade do ar que precede a condensação. Esse método é mais confiável que o critério de 100% de umidade, que pode causar falsos alarmes devido a imprecisão dos sensores de umidade em geral e por não considerar a influência dos ventos que dificultam a condensação. O trabalho apresenta o método de construção desse sensor e os testes de avaliação. Sugere-se portanto a inclusão desse sensor nas estações meteorológicas dos telescópios do país.

  9. Route to three-dimensional fragments using diversity-oriented synthesis

    PubMed Central

    Hung, Alvin W.; Ramek, Alex; Wang, Yikai; Kaya, Taner; Wilson, J. Anthony; Clemons, Paul A.; Young, Damian W.

    2011-01-01

    Fragment-based drug discovery (FBDD) has proven to be an effective means of producing high-quality chemical ligands as starting points for drug-discovery pursuits. The increasing number of clinical candidate drugs developed using FBDD approaches is a testament of the efficacy of this approach. The success of fragment-based methods is highly dependent on the identity of the fragment library used for screening. The vast majority of FBDD has centered on the use of sp2-rich aromatic compounds. An expanded set of fragments that possess more 3D character would provide access to a larger chemical space of fragments than those currently used. Diversity-oriented synthesis (DOS) aims to efficiently generate a set of molecules diverse in skeletal and stereochemical properties. Molecules derived from DOS have also displayed significant success in the modulation of function of various “difficult” targets. Herein, we describe the application of DOS toward the construction of a unique set of fragments containing highly sp3-rich skeletons for fragment-based screening. Using cheminformatic analysis, we quantified the shapes and physical properties of the new 3D fragments and compared them with a database containing known fragment-like molecules. PMID:21482811

  10. Route to three-dimensional fragments using diversity-oriented synthesis.

    PubMed

    Hung, Alvin W; Ramek, Alex; Wang, Yikai; Kaya, Taner; Wilson, J Anthony; Clemons, Paul A; Young, Damian W

    2011-04-26

    Fragment-based drug discovery (FBDD) has proven to be an effective means of producing high-quality chemical ligands as starting points for drug-discovery pursuits. The increasing number of clinical candidate drugs developed using FBDD approaches is a testament of the efficacy of this approach. The success of fragment-based methods is highly dependent on the identity of the fragment library used for screening. The vast majority of FBDD has centered on the use of sp(2)-rich aromatic compounds. An expanded set of fragments that possess more 3D character would provide access to a larger chemical space of fragments than those currently used. Diversity-oriented synthesis (DOS) aims to efficiently generate a set of molecules diverse in skeletal and stereochemical properties. Molecules derived from DOS have also displayed significant success in the modulation of function of various "difficult" targets. Herein, we describe the application of DOS toward the construction of a unique set of fragments containing highly sp(3)-rich skeletons for fragment-based screening. Using cheminformatic analysis, we quantified the shapes and physical properties of the new 3D fragments and compared them with a database containing known fragment-like molecules.

  11. Nuclear inelastic scattering at the diiron center of ribonucleotide reductase from Escherichia coli

    NASA Astrophysics Data System (ADS)

    Marx, J.; Srinivas, V.; Faus, I.; Auerbach, H.; Scherthan, L.; Jenni, K.; Chumakov, A. I.; Rüffer, R.; Högbom, M.; Haumann, M.; Schünemann, V.

    2017-11-01

    The enzyme ribonucleotide reductase R2 catalyzes an important step in the synthesis of the building blocks of DNA, and harbors a dinuclear iron center required for activity. Not only the iron valence states but also the protonation of the iron ligands govern the enzymatic activity of the enzyme. We have performed Nuclear Inelastic Scattering (NIS) experiments on the 57Fe reconstituted ribonucleotide reductase R2 subunit from Escherichia coli ( Ec R2a). Accompanying Mössbauer spectroscopic investigations show that the partial density of vibrational states (pDOS) of the 57Fe reconstituted Ec R2a sample contained contributions from both 57Fe- Ec R2a protein as well as unspecifically bound 57Fe. Subtraction of a featureless pDOS as obtained from protein-coated iron oxide particles allowed modeling of the contribution of non-specifically bound iron and thus the pDOS of 57Fe- Ec R2a could be obtained. Quantum-mechanics/molecular-mechanics (QM/MM) calculations of the whole 57Fe- Ec R2a protein with variations of the cofactor protonation were performed in order to assign characteristic bands to their corresponding molecular vibrational modes.

  12. Embolização arterial superseletiva para tratamento de angiomiolipoma em paciente com rim único

    PubMed Central

    Góes, Adenauer Marinho de Oliveira; Jeha, Salim Abdon Haber; Salgado, José Rui Couto

    2016-01-01

    Resumo Os autores relatam o caso de uma paciente jovem previamente submetida a nefrectomia direita por apresentar angiomiolipomas renais (AMLRs) e portadora de dois volumosos angiomiolipomas no rim esquerdo remanescente. A paciente foi encaminhada pelo urologista para tratamento endovascular. Realizou-se embolização superseletiva de um dos tumores, localizado no polo renal inferior e em situação subcapsular; apesar de várias tentativas, não foi obtido um cateterismo seletivo suficiente para embolizar o segundo angiomiolipoma (localizado no polo renal superior) sem que um volume considerável de parênquima renal adjacente sofresse isquemia. O procedimento e a recuperação da paciente transcorreram sem complicações. A paciente recebeu alta no primeiro pós-operatório e vem sendo acompanhada ambulatorialmente há 9 meses sem intercorrências. É feita uma breve revisão sobre indicações, aspectos técnicos e complicações do tratamento endovascular dos AMLRs, além de serem discutidas vantagens dessa técnica quando comparada à ressecção cirúrgica dos tumores. PMID:29930580

  13. Intergranular Corrosion Behavior of Low-Nickel and 304 Austenitic Stainless Steels

    NASA Astrophysics Data System (ADS)

    Bansod, Ankur V.; Patil, Awanikumar P.; Moon, Abhijeet P.; Khobragade, Nilay N.

    2016-09-01

    Intergranular corrosion (IGC) susceptibility for Cr-Mn austenitic stainless steel and 304 austenitic stainless steel (ASS) was estimated using electrochemical techniques. Optical and SEM microscopy studies were carried out to investigate the nature of IGC at 700 °C with increasing time (15, 30, 60, 180, 360, 720, 1440 min) according to ASTM standard 262 A. Quantitative analysis was performed to estimate the degree of sensitization (DOS) using double loop electrochemical potentiokinetic reactivation (DLEPR) and EIS technique. DLEPR results indicated that with the increase in thermal aging duration, DOS becomes more severe for both types of stainless steel. The DOS for Cr-Mn ASS was found to be higher (65.12% for 1440 min) than that of the AISI 304 ASS (23% for 1440 min). The higher degree of sensitization resulted in lowering of electrical charge capacitance resistance. Chronoamperometry studies were carried out at a passive potential of 0.4 V versus SCE and was observed to have a higher anodic dissolution of the passive film of Cr-Mn ASS. EDS studies show the formation of chromium carbide precipitates in the vicinity of the grain boundary. The higher Mn content was also observed for Cr-Mn ASS at the grain boundary.

  14. Freehand diffuse optical spectroscopy imaging for intraoperative identification of major venous and arterial vessels underlying peritoneal fat: an in vivo demonstration in a pig model

    NASA Astrophysics Data System (ADS)

    Piao, Daqing; Ramadan, Mohammad; Park, Aaron; Bartels, Kenneth E.; Patel, Sanjay G.

    2017-10-01

    Inadvertent injury to important anatomic structures is a significant risk in minimally invasive surgery (MIS) that potentially requires conversion to an open procedure, which results in increased morbidity and mortality. Surgeons operating minimal-invasively currently do not have an easy-to-use, real-time device to aid in intraoperative identification of important anatomic structures that underlie tissue planes. We demonstrate freehand diffuse optical spectroscopy (DOS) imaging for intraoperatively identifying major underlying veins and arteries. An applicator probe that can be affixed to and detached from an 8-mm laparoscopic instrument has been developed. The 10-mm DOS source-detector separation renders sampling of tissue heterogeneities a few millimeters deep. DOS spectra acquired consecutively during freehand movement of the applicator probe on the tissue surface are displayed as a temporal and spectral image to assist in spatially resolved identification of the underlying structures. Open surgery identifications of the vena cava and aorta underlying peritoneal fat of ˜4 mm in thickness using the applicator probe under room light were demonstrated repeatedly in multiple pigs in vivo.

  15. Católicos, fidelidade conjugal e AIDS: entre a cruz da doutrina moral e as espadas do cotidiano sexual dos adeptos1

    PubMed Central

    Rios, Luis Felipe; de Aquino, Francisca Luciana; Muñoz-Laboy, Miguel; Oliveira, Cinthia; Parker, Richard

    2009-01-01

    Neste artigo discutimos a visão da Igreja Católica sobre sexualidade na interface com a epidemia do HIV/AIDS. Nossa reflexão está embasada em pesquisa etnográfica que envolveu dois meses de observação participante do cotidiano de católicos de um bairro popular da Região Metropolitana do Recife, além de contar com entrevistas a onze dos leigos engajados nos serviços religiosos da igreja do bairro e a oito sacerdotes que realizam seus trabalhos religiosos em outras localidades. Nelas abordamos diferentes temáticas relacionadas ao enfrentamento da epidemia da AIDS. Nesse contexto, conjugalidade e fidelidade se afiguram como importantes analisadores de como aqueles lidam com a epidemia, em uma variedade de re-descrições práticas e de re-interpretações conceptuais das assertivas do discurso moral religioso – ainda que, muitos impasses permaneçam em aberto em termos das prerrogativas da Igreja e seus possíveis rebatimentos na saúde sexual dos adeptos. PMID:21765650

  16. Impact of doping on the density of states and the mobility in organic semiconductors

    NASA Astrophysics Data System (ADS)

    Zuo, Guangzheng; Abdalla, Hassan; Kemerink, Martijn

    2016-06-01

    We experimentally investigated conductivity and mobility of poly(3-hexylthiophene) (P3HT) doped with tetrafluorotetracyanoquinodimethane (F4TCNQ ) for various relative doping concentrations ranging from ultralow (10-5) to high (10-1) and various active layer thicknesses. Although the measured conductivity monotonously increases with increasing doping concentration, the mobilities decrease, in agreement with previously published work. Additionally, we developed a simple yet quantitative model to rationalize the results on basis of a modification of the density of states (DOS) by the Coulomb potentials of ionized dopants. The DOS was integrated in a three-dimensional (3D) hopping formalism in which parameters such as energetic disorder, intersite distance, energy level difference, and temperature were varied. We compared predictions of our model as well as those of a previously developed model to kinetic Monte Carlo (MC) modeling and found that only the former model accurately reproduces the mobility of MC modeling in a large part of the parameter space. Importantly, both our model and MC simulations are in good agreement with experiments; the crucial ingredient to both is the formation of a deep trap tail in the Gaussian DOS with increasing doping concentration.

  17. Observation of van Hove singularity and quasiparticle interference in KFe2 As2 superconductors revealed by STM/STS measurements

    NASA Astrophysics Data System (ADS)

    Wen, Hai-Hu; Fang, Delong; Du, Zengyi; Wang, Zhenyu; Yang, Huan; Ding, Xiaxin

    2015-03-01

    We have conducted STM/STS investigations on the KFe2As2 superconducting single crystals down to 0.45 K under magnetic field. Clear electronic standing waves have been observed allowing us to investigate the quasiparticle interference (QPI). Interestingly we observed a sharp peak of local density of states (LDOS) near the Fermi energy showing evidence of strongly enhanced DOS both below and above Tc. We demonstrate that this is induced by a van Hove singularity with the saddle point locating only 4 meV below the Fermi energy. Below Tc it is found that only 20% of the normal state DOS is gapped away by superconductivity, with the major part of DOS due to VHS ungapped. Combing with the ARPES data, we find that the VHS points locate on the (π,0) point, which gives strong constraint on the gap function and pairing mechanism. In the mixed state we clearly observed the mixture of vortices and the standing waves due to quasiparticle interference, giving support to above picture. In collaboration with X. Shi, P. Richard, T. Qian and H. Ding et al. in Institute of Physics, CAS.

  18. Influence of essential onion oil on tin and chromium dissolution from tinplate.

    PubMed

    Nincević Grassino, A; Grabarić, Z; Pezzani, A; Fasanaro, G; Lo Voi, A

    2009-07-01

    During food and beverage packaging in tinplate cans the dissolution of tin and chromium into food content may occur. To protect metallic surface different corrosion inhibitors are recommended, nowadays particularly a new group of natural products is of interest. In this work the influence of essential onion oil (EOO) on metals dissolution (tin and chromium) from tinplate sheets before food canning was investigated. The analyses were performed by galvanostatic method and atomic absorption spectroscopy. The values of tin obtained for the internal surface of tinplate covered with EOO (7.31-9.76 gm(-2)) are lower than the values when dioctyl sebacate oil (DOS), as a protective tinplate surface layer for food caning, was used (9.24-11.03 gm(-2)). Obviously, the presence of EOO diminished more efficiently then DOS oil the dissolution of tin in electrolyte during galvanostatic analyses. The efficiency of EOO as corrosion inhibitor was even more pronounced in the case of chromium where the dissolution from 1.8-2.5 mgm(-2) (DOS oil) was lowered to 1.0-1.3 mgm(-2) (EOO). Correlation of results obtained with two different physico-chemical methods was satisfying.

  19. A atuação do Observatório Nacional registrada nos relatórios ministeriais 1889 a 1930

    NASA Astrophysics Data System (ADS)

    Rodrigues, T.

    2003-08-01

    O período republicano até 1930 foi marcante na história do Observatório Nacional. Diversas reformas levaram a instituição a três ministérios diferentes e mudaram a ênfase do seu trabalho. A tão aguardada mudança para uma nova sede, em São Cristóvão, em 1920, não foi suficiente para que a instituição acompanhasse o ritmo tomado pela astronomia no mundo e se firmasse como ambiente de pesquisa. Uma análise simplificada poderia caracterizar um período de produção científica insignificante, dado o distanciamento da instituição dos novos rumos da astrofísica e da rápida inovação dos instrumentos, além do pequeno volume de publicações. Era uma época em que ainda não existiam os mecanismos formais de apoio e avaliação da atividade científica. Esse trabalho procura identificar a real atividade do Observatório no conteúdo dos Relatórios Ministeriais que, ao final de cada ano, apresentava as atividades, sucessos e problemas enfrentados pela instituição. Questões como instrumental e recursos humanos necessários; entraves burocráticos e financeiros; e articulações com outros observatórios se complementaram entre si ao longo desses anos para definir o perfil institucional e alguns aspectos fundamentais para a construção da astronomia no país. É possível concluir que a ênfase em serviços geográficos e de meteorologia, ao lado da inadequação dos instrumentos e do local, quase fizeram desaparecer a pesquisa em astronomia. Porém, vale destacar a sobrevivência de alguns trabalhos, como, por exemplo, variação de latitude e observação de estrelas duplas que mantiveram importante intercâmbio com outros grupos de pesquisa, demonstrando o constante esforço dos astrônomos e das diretorias em defesa da atividade científica.

  20. A Influência da Escola e da Mídia na Obtenção dos Conhecimentos Astronômicos

    NASA Astrophysics Data System (ADS)

    da Cunha, W. S.; Voelzke, M. R.; Amaral, L. H.

    2006-08-01

    O universo em que vivemos possui segredos jamais imaginados pelo homem, fruto da pequena proporção que ocupamos diante de um cosmos infinito. A astronomia funciona como um instrumento que sacia a sede humana em desvendar esses segredos, estudando as galáxias, quasares, pulsares além da existência de todos os elementos que preenchem o espaço cósmico, o vácuo, não mais vazio como se pensou em outros tempos. A mídia explora esse campo de forma mística e também científica. A difusão adequada e dentro dos padrões educacionais vigentes, de conceitos astronômicos, se faz necessária, devido sua presença nos conteúdos escolares, centros de ciência e na mídia, de modo geral. A reforma do Currículo Básico da Escola Pública da maioria dos Estados brasileiros introduziu conceitos astronômicos desde a pré-escola até o Ensino Médio. Num estudo realizado com 1.032 alunos do Ensino Médio de seis escolas estaduais, revelou-se através da aplicação de um questionário que abordava conheciment os básicos em astronomia, como estes foram adquiridos e qual era a infra-estrutura oferecida pela escola: para 66,2% dos entrevistados o professor já fez alguma apresentação a respeito de astronomia. O presente estudo revelou também que 44,5% dos alunos entrevistados adquiriram seus conhecimentos astronômicos na escola, 28,1% através da televisão e 27,4% afirmaram que seus conhecimentos foram obtidos através de outros tipos de mídia (internet, filmes e revistas). Embora o estudo revele claramente que há certo equilíbrio na forma em que os alunos obtiveram seus conhecimentos astronômicos, a mídia ainda explora e muitas vezes desperta o interesse pela astronomia com assuntos que não fazem parte de nosso cotidiano como, por exemplo, o homem na Lua, os projetos espaciais e a primeira viagem de um astronauta brasileiro no espaço. Porém, em certos casos, a mídia pode promover conhecimentos incompletos ou mesmo equivocados sobre os conceitos que envolvam a astronomia, como por exemplo a propagação do som no vácuo observado na maioria dos filmes de f icção científica ou da existência das estações do ano em função da distância da Terra ao Sol, em conformidade com o questionário aplicado.

  1. Classificação geométrica de galáxias bianeladas através do metódo CART (Classification And Regression Trees)

    NASA Astrophysics Data System (ADS)

    Ormeño, M. I.; Faúndez-Abans, M.; Cavada, G.

    2003-08-01

    A importância deste trabalho deve-se à seleção de objetos ainda não tratados particularmente como uma família e ao emprego de procedimento estatístico robusto que não precisa de pressupostos ou condições de contorno. Contribui, assim, ao melhor entendimento do cenário das Galáxias Aneladas do diagrama de Hubble via classificação e estudo de subclasses. Selecionaram-se 100 galáxias possuidoras de dois anéis do Catalog of Southern Ringed Galaxies compilado por Ronald Buta, de modo a construir uma amostra completa em termos de conhecimento dos semi-eixos dos anéis interno e externo projetados no plano do céu. Visando uma possível classificação destas galáxias aneladas normais em famílias de acordo com as características geométricas dos anéis, empregou-se primeiramente a Análise de Aglomerados (ferramenta de classificação: medições de semelhança em um espaço bidimensional) para explorar a possível existência de famílias. As variáveis analisadas foram: os diâmetros interiores menores d(I) e maiores D(I), os diâmetros exteriores menores d(E) e maiores D(E), e os ângulos de inclinação dos semi-eixos maiores interiores q(I) e exteriores q(E) dos anéis. Como metodologia de discriminação, empregou-se a construção de Árvores de Classificação. As árvores de classificação constituem um método de discriminação alternativo aos modelos clássicos, tais como a Análise Discriminante e a Regressão Logística, onde uma base de dados é dividida em partições (subgrupos) da árvore por ação de um predictor (variável específica). Os pacotes estatísticos utilizados para o processamento da informação foram: SAS versão 8.0 (Statistical Analisys System) e CART versão 3.6.3. Esta análise estatística sugere a existência de três possíveis famílias de galáxias bianeladas, com base apenas na geometria dos anéis. Como forma exploratória inicial deste resultado, a construção de um diagrama BT (magnitude total) versus o índice de cor (B-R), mostra que os três grupos distribuem-se de forma praticamente contínua, porém discriminadas entre si, ocupando três regiões distintas. A classe 3, por exemplo, é geralmente a mais azul, sendo a Classe 1 a mais avermelhada.

  2. Taking a look to promoting health and complications' prevention: differences by context.

    PubMed

    Freire, Rosa Maria de Albuquerque; Landeiro, Maria José Lumini; Martins, Maria Manuela Ferreira Pereira da Silva; Martins, Teresa; Peres, Heloísa Helena Ciqueto

    2016-08-08

    to acknowledge and compare the health promotion and complications' prevention practices performed by nurses working in hospital and primary health care contexts. descriptive, exploratory and crosscutting study, performed with 474 nurses selected by convenience sampling. It was used a form that encompassed two categories of descriptive statements about quality in the professional exercise of nurses. This study had ethical committee approval. the nurses' population was mainly women (87,3%) with an average age of 35,5 years. There was more practices of the hospital's nurses related to the identification of potential problems of the patient (p=0.001) and supervision of the activities that put in place the nursing interventions and the activities that they delegate (p=0.003). the nurses perform health promotion and complications' prevention activities, however not in a systematic fashion and professional practices differ by context. This study is relevant as it may promote the critical consciousness of the nurses about the need of stressing quality practices. conhecer e comparar as práticas de promoção da saúde e prevenção de complicações de enfermeiros que exercem em contexto hospitalar e em cuidados de atenção básica à saúde. estudo descritivo, exploratório e transversal desenvolvido com 474 enfermeiros, selecionados por meio de amostragem por conveniência. Foi utilizado questionário que integrou duas categorias de enunciados descritivos de qualidade do exercício profissional dos enfermeiros. O estudo foi aprovado em comitê de ética. a maioria dos enfermeiros era do sexo feminino (87,3%), com idade média de 35,5 anos. Houve mais práticas dos enfermeiros dos cuidados básicos à saúde relativamente a promoção de estilos de vida saudável (<0.001) e encaminhamento de situações problemáticas identificadas, para outros profissionais (p=0.039). Houve mais práticas dos enfermeiros do hospital relativamente a identificação dos problemas potenciais do paciente (p=0.001) e supervisão das atividades que concretizam as intervenções de enfermagem e as atividades que delegam (p=0.003). os enfermeiros realizam atividades de promoção da saúde e prevenção de complicações, porém, não de forma sistemática e as práticas profissionais diferem com relação ao contexto. Este estudo é relevante na medida em que pode promover a conscientização dos enfermeiros para a necessidade de reforçar práticas de qualidade. conocer y comparar las practicas de promoción de la salud y prevención de complicaciones, de los enfermeros que ejercen en el contexto de hospitales y en cuidados de atención primaria de salud. estudio descriptivo, exploratorio y transversal, desarrollado con 474 enfermeros, seleccionados por muestreo de conveniencia. Se utilizó un cuestionario que integra dos categorías de enunciados descriptivos de la calidad del ejercicio profesional de los enfermeros. El estudio fue aprobado en comité de ética. la mayoría de los enfermeros eran del sexo femenino (87,3%) con una edad promedio de 35,5 años. Se encontraron mayor cantidad de prácticas de estos enfermeros en cuidados primarios en relación a la promoción de estilos de vida saludable (<0.001) y referencia de situaciones problemáticas para otros profesionales (p=0.039). También se encontraron más prácticas de los enfermeros de hospital en relación a identificación de problemas potenciales del paciente (p=0.001) y supervisión de las actividades que concretan las intervenciones de enfermería y las actividades que delegan (p=0.003). los enfermeros realizan actividades de promoción de salud y prevención de complicaciones, sin embargo, no en forma sistemática, y las prácticas varían en relación al contexto. Este estudio es relevante en la medida que puede promover la concientización de los enfermeros para la necesidad de reforzar prácticas de calidad.

  3. Contribution of Oswaldo Paulo Forattini to public health: analysis of scientific production.

    PubMed

    Reis, Juliana Gonçalves; Kobayashi, Keilla Miki; Ueno, Helene Mariko; Ribeiro, Cristiane Martins; Cardoso, Telma Abdalla de Oliveira

    2016-12-22

    To analyze the main characteristics of the scientific production of Oswaldo Paulo Forattini, researcher and, for 40 years, editor of Revista de Saúde Pública. Descriptive study with bibliometric approach conducted in three steps. (1) identification of bibliographic records using the following search strategy: "Oswaldo Paulo Forattini" OR "Forattini OP" OR "Forattini" up information sources Google Scholar, Web of Science, and PubMed, in July 2016, which retrieved 867 records. (2) composition of research corpus, in which we included 351 bibliographic records of articles, books, book chapters, editorials, book reviews, informative notes and annual reports of the RSP and excluded 516 duplicates and acknowledgement notes, obituary notes, and nonretrievable citations. (3) data organization and analysis, in which we built databases for descriptive analysis and development of the MeSH coauthors and terms networks in VOSviewer software. For analysis of editorials, three reviewers read the full text of each editorial and categorized them according to subject, historical context and perspectives, relating them with historical milestones. Forattini's scientific production occurred from 1946 to 2009, most consisting of articles (n = 218; 62.1%), editorials (n = 43; 12.3%), and books (n = 13; 3.7%). The main subjects were Culicidae (36.8%), Triatominae (12.5%), and Epidemiology (10.0%). The coauthors of articles were his professors, colleagues of his generation, and graduate students. His editorials addressed critical reflections on the production of knowledge, research priorities, and factors that contributed to or hindered progress. The scope of subjects is broad, referring to socioeconomic and scientific development, public health issues in developed countries, or global health. The analysis shows Forattini's commitment with public health, research with vectors, training of researchers, and scientific communication. Analisar as principais características da produção científica de Oswaldo Paulo Forattini, pesquisador e, por 40 anos, editor da Revista de Saúde Pública. Estudo descritivo com abordagem bibliométrica realizado em três etapas. (1) Identificação dos registros bibliográficos, utilizando a seguinte estratégia de busca: "Oswaldo Paulo Forattini" OR "Forattini OP" OR "Forattini O" nas fontes de informação Google Scholar, Web of Science e PubMed, em julho de 2016, o que recuperou 867 registros. (2) Composição do corpus da pesquisa, na qual foram incluídos 351 registros bibliográficos de artigos, livros, capítulos de livros, editoriais, resenhas de livros, notas informativas e relatórios anuais da RSP e excluídos 516 duplicatas e notas de agradecimento, notas de obituários e citações não recuperáveis. (3) Organização e análise dos dados, na qual foram construídos bancos de dados para análise descritiva e elaboração das redes de coautores e de termos do MeSH no software VOSviewer. Para análise dos editoriais, três revisores leram o texto completo de cada editorial e os categorizaram segundo assunto, contexto histórico e perspectivas, relacionando-o com marcos históricos. A produção científica de Forattini ocorreu de 1946 a 2009, a maioria composta por artigos (n = 218; 62,1%), editoriais (n = 43; 12,3%) e livros (n = 13; 3,7%). Os principais assuntos foram Culicidae (36,8%), Triatominae (12,5%) e Epidemiologia (10,0%). Os coautores dos artigos foram seus mestres, colegas de sua geração e alunos de pós-graduação. Seus editoriais abordaram reflexões críticas sobre a produção de conhecimento, prioridades em pesquisa e fatores que contribuíam ou desfavoreciam o progresso. O escopo dos assuntos é amplo, remetendo ao desenvolvimento científico e socioeconômico, questões de saúde pública em países desenvolvidos ou saúde global. A análise mostra o comprometimento de Forattini com a saúde pública, na pesquisa com vetores, na formação de pesquisadores e na comunicação científica.

  4. Contact and Bandgap Engineering in Two Dimensional Crystal

    NASA Astrophysics Data System (ADS)

    Chu, Tao

    At the heart of semiconductor research, bandgap is one of the key parameters for materials and determine their applications in modern technologies. For traditional bulk semiconductors, the bandgap is determined by the chemical composition and specific arrangement of the crystal lattices, and usually invariant during the device operation. Nevertheless, it is highly desirable for many optoelectronic and electronic applications to have materials with continuously tunable bandgap available. In the past decade, 2D layered materials including graphene and transition metal dichalcogenides (TMDs) have sparked interest in the scientific community, owing to their unique material properties and tremendous potential in various applications. Among many newly discovered properties that are non-existent in bulk materials, the strong in-plane bonding and weak van der Waals inter-planar interaction in these 2D layered structures leads to a widely tunable bandgap by electric field. This provides an extra knob to engineer the fundamental material properties and open a new design space for novel device operation. This thesis focuses on this field controlled dynamic bandgap and can be divided into three parts: (1) bilayer graphene is the first known 2D crystal with a bandgap can be continuously tuned by electric field. However, the electrical transport bandgaps is much smaller than both theoretical predictions and extracted bandgaps from optical measurements. In the first part of the thesis, the limiting factors of preventing achieving a large transport bandgap in bilayer graphene are investigated and different strategies to achieve a large transport bandgap are discussed, including the vertically scaling of gate oxide and patterning channel into ribbon structure. With a record large transport bandgap of ~200meV, a dual-gated semiconducting bilayer graphene P/N junction with extremely scaled gap of 20nm in-between is fabricated. A tunable local maxima feature, associated with 1D vHs DOS at the band edge of bilayer graphene, was experimentally observed in transport for the first time. (2) The bandgap of bilayer MoS2 is also predicted to be continuously tuned to zero by applying a perpendicular electric field. Here, the first experimental realization of tuning the bandgap of bilayer MoS2 by a vertical electric field is presented. An analytical approach utilizing the threshold voltages from ambipolar characteristics is employed to quantitatively extract bandgaps, which is further benchmarked by temperature dependent bandgap measurements and photoluminescence measurements. (3) Few layer graphene is employed as an example to demonstrate a novel self-aligned edge contacting scheme for layered material systems.

  5. Professional and spatial mobility of osteopathic physicians.

    PubMed

    Hassinger, E W; Gill, L S; Hobbs, D J; Hageman, R L

    1979-12-01

    The study examines changes in location of osteopathic and medical doctors in a 20-county area of rural Missouri over a 14-year period. Losses of osteopathic physicians were greater than medical doctors. However, there was a convergence over the 14-year period in background characteristics of the two types of physicians. The finding of greater spatial mobility of DOs is placed in the context of professional mobility of osteopathy. It is also argued that as practice opportunities for DOs increase, background factors associated with early socialization become more influential in choice of practice sites. The relationship of practice opportunities to choice of practice sites can be extended to foreign medical school graduates and "new health practitioners."

  6. Scanning, non-contact, hybrid broadband diffuse optical spectroscopy and diffuse correlation spectroscopy system.

    PubMed

    Johansson, Johannes D; Mireles, Miguel; Morales-Dalmau, Jordi; Farzam, Parisa; Martínez-Lozano, Mar; Casanovas, Oriol; Durduran, Turgut

    2016-02-01

    A scanning system for small animal imaging using non-contact, hybrid broadband diffuse optical spectroscopy (ncDOS) and diffuse correlation spectroscopy (ncDCS) is presented. The ncDOS uses a two-dimensional spectrophotometer retrieving broadband (610-900 nm) spectral information from up to fifty-seven source-detector distances between 2 and 5 mm. The ncDCS data is simultaneously acquired from four source-detector pairs. The sample is scanned in two dimensions while tracking variations in height. The system has been validated with liquid phantoms, demonstrated in vivo on a human fingertip during an arm cuff occlusion and on a group of mice with xenoimplanted renal cell carcinoma.

  7. An MS-DOS-based program for analyzing plutonium gamma-ray spectra

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ruhter, W.D.; Buckley, W.M.

    1989-09-07

    A plutonium gamma-ray analysis system that operates on MS-DOS-based computers has been developed for the International Atomic Energy Agency (IAEA) to perform in-field analysis of plutonium gamma-ray spectra for plutonium isotopics. The program titled IAEAPU consists of three separate applications: a data-transfer application for transferring spectral data from a CICERO multichannel analyzer to a binary data file, a data-analysis application to analyze plutonium gamma-ray spectra, for plutonium isotopic ratios and weight percents of total plutonium, and a data-quality assurance application to check spectral data for proper data-acquisition setup and performance. Volume 3 contains the software listings for these applications.

  8. Microgravity computing codes. User's guide

    NASA Astrophysics Data System (ADS)

    1982-01-01

    Codes used in microgravity experiments to compute fluid parameters and to obtain data graphically are introduced. The computer programs are stored on two diskettes, compatible with the floppy disk drives of the Apple 2. Two versions of both disks are available (DOS-2 and DOS-3). The codes are written in BASIC and are structured as interactive programs. Interaction takes place through the keyboard of any Apple 2-48K standard system with single floppy disk drive. The programs are protected against wrong commands given by the operator. The programs are described step by step in the same order as the instructions displayed on the monitor. Most of these instructions are shown, with samples of computation and of graphics.

  9. A natural product based DOS library of hybrid systems.

    PubMed

    Prabhu, Ganesh; Agarwal, Shalini; Sharma, Vijeta; Madurkar, Sanjay M; Munshi, Parthapratim; Singh, Shailja; Sen, Subhabrata

    2015-05-05

    Here we described a natural product inspired modular DOS strategy for the synthesis of a library of hybrid systems that are structurally and stereochemically disparate. The main scaffold is a pyrroloisoquinoline motif, that is synthesized from tandem Pictet-Spengler lactamization. The structural diversity is generated via "privileged scaffolds" that are attached at the appropriate site of the motif. Screening of the library compounds for their antiplasmodial activity against chloroquine sensitive 3D7 cells indicated few compounds with moderate activity (20-50 μM). A systematic comparison of structural intricacy between the library members and a natural product dataset obtained from ZINC(®) revealed comparable complexity. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  10. A dynamical mean-field study of orbital-selective Mott phase enhanced by next-nearest neighbor hopping

    NASA Astrophysics Data System (ADS)

    Niu, Yuekun; Sun, Jian; Ni, Yu; Song, Yun

    2018-06-01

    The dynamical mean-field theory is employed to study the orbital-selective Mott transition (OSMT) of the two-orbital Hubbard model with nearest neighbor hopping and next-nearest neighbor (NNN) hopping. The NNN hopping breaks the particle-hole symmetry at half filling and gives rise to an asymmetric density of states (DOS). Our calculations show that the broken symmetry of DOS benefits the OSMT, where the region of the orbital-selective Mott phase significantly extends with the increasing NNN hopping integral. We also find that Hund's rule coupling promotes OSMT by blocking the orbital fluctuations, but the influence of NNN hopping is more remarkable.

  11. Estudio de los Efectos Gravitomagnéticos en Cuerpos Masivos Rotantes

    NASA Astrophysics Data System (ADS)

    Velandia Heredia, N.; Tejeiro, J. M.

    2008-03-01

    A partir del estudio de los Efectos Gravitomagnéticos en cuerpos masivos rotantes, planteamos la expresión para medir el desfase en el tiempo, para diferentes observadores, que se dan cuando viajan dos rayos de luz por una guía de onda o de manera libre (geodésicas), en el plano azimutal y en el plano polar. Con lo anterior queremos abordar el experimento tipo Michelson y Morley, de forma que podamos involucrar el valor de la densidad del momento angular (a) en el retraso temporal para los dos haces de luz que viajan por los brazos del interferómetro, cuando este último es ubicado en el plano ecuatorial.

  12. Graphene for amino acid biosensing: Theoretical study of the electronic transport

    NASA Astrophysics Data System (ADS)

    Rodríguez, S. J.; Makinistian, L.; Albanesi, E. A.

    2017-10-01

    The study of biosensors based on graphene has increased in the last years, the combination of excellent electrical properties and low noise makes graphene a material for next generation electronic devices. This work discusses the application of a graphene-based biosensor for the detection of amino acids histidine (His), alanine (Ala), aspartic acid (Asp), and tyrosine (Tyr). First, we present the results of modeling from first principles the adsorption of the four amino acids on a graphene sheet, we calculate adsorption energy, substrate-adsorbate distance, equilibrium geometrical configurations (upon relaxation) and densities of states (DOS) for each biomolecule adsorbed. Furthermore, in order to evaluate the effects of amino acid adsorption on the electronic transport of graphene, we modeled a device using first-principles calculations with a combination of Density Functional Theory (DFT) and Nonequilibrium Greens Functions (NEGF). We provide with a detailed discussion in terms of transmission, current-voltage curves, and charge transfer. We found evidence of differences in the electronic transport through the graphene sheet due to amino acid adsorption, reinforcing the possibility of graphene-based sensors for amino acid sequencing of proteins.

  13. User's manual for the Gaussian windows program

    NASA Technical Reports Server (NTRS)

    Jaeckel, Louis A.

    1992-01-01

    'Gaussian Windows' is a method for exploring a set of multivariate data, in order to estimate the shape of the underlying density function. The method can be used to find and describe structural features in the data. The method is described in two earlier papers. I assume that the reader has access to both of these papers, so I will not repeat material from them. The program described herein is written in BASIC and it runs on an IBM PC or PS/2 with the DOS 3.3 operating system. Although the program is slow and has limited memory space, it is adequate for experimenting with the method. Since it is written in BASIC, it is relatively easy to modify. The program and some related files are available on a 3-inch diskette. A listing of the program is also available. This user's manual explains the use of the program. First, it gives a brief tutorial, illustrating some of the program's features with a set of artificial data. Then, it describes the results displayed after the program does a Gaussian window, and it explains each of the items on the various menus.

  14. Impacto del Seguro Popular en el gasto catastrófico y de bolsillo en el México rural y urbano, 2005–2008

    PubMed Central

    Sosa-Rubí, Sandra G; Salinas-Rodríguez, Aarón; Galárraga, Omar

    2016-01-01

    Objetivo Estimar el efecto del Seguro Popular (SP) sobre la incidencia del gasto catastrófico en salud (GCS) y sobre el gasto de bolsillo en salud (GBS) en el mediano plazo. Material y métodos Con base en la Encuesta de Evaluación del Seguro Popular (2005–2008), se analizaron los resultados del efecto del SP en la cohorte rural para dos años de seguimiento (2006 y 2008) y en la cohorte urbana para un año (2008). Resultados A nivel conglomerado no se detectaron efectos del SP. A nivel hogar se encontró que el SP tiene un efecto protector en el GCS y en el GBS en consulta externa y hospitalización en zonas rurales; y efectos significativos en la reducción de GBS en consulta externa en zonas urbanas. Conclusiones El SP se muestra como un programa efectivo para proteger a los hogares contra gastos de bolsillo por motivos de salud en el mediano plazo. PMID:22282205

  15. Electronic structure and electron-phonon coupling in TiH$$_2$$

    DOE PAGES

    Shanavas, Kavungal Veedu; Lindsay, Lucas R.; Parker, David S.

    2016-06-15

    Calculations using first principles methods and strong coupling theory are carried out to understand the electronic structure and superconductivity in cubic and tetragonal TiHmore » $$_2$$. A large electronic density of states at the Fermi level in the cubic phase arises from Ti-$$t_{2g}$$ states and leads to a structural instability against tetragonal distortion at low temperatures. However, constraining the in-plane lattice constants diminishes the energy gain associated with the tetragonal distortion, allowing the cubic phase to be stable at low temperatures. Furthermore, calculated phonon dispersions show decoupled acoustic and optic modes arising from Ti and H vibrations, respectively and frequencies of optic modes to be rather high. The cubic phase has a large electron-phonon coupling parameter $$\\lambda$$ and critical temperature of several K. Contribution of the hydrogen sublattice to $$\\lambda$$ is found to be small in this material, which we understand from strong coupling theory to be due to the small H-$s$ DOS at the Fermi level and high energy of hydrogen modes at the tetrahedral sites.« less

  16. Dividing the Concentrator Target From the Genesis Mission

    NASA Technical Reports Server (NTRS)

    Lauer, H. V., Jr.; Burkett, P. J.; Clemett, S. J.; Gonzales, C. P.; Nakamura-Messenger, K.; Rodriquez, M. C.; See, T. H.; Sutter, B.

    2014-01-01

    The Genesis spacecraft, launched in 2001, traveled to a Lagrangian point between the Earth and Sun to collect particles from the solar wind and return them to Earth. However, during the return of the spacecraft in 2004, the parachute failed to open during descent, and the Genesis spacecraft crashed into the Utah desert. Many of the solar wind collectors were broken into smaller pieces, and the field team rapidly collected the capsule and collector pieces for later assessment. On each of the next few days, the team discovered that various collectors had survived intact, including three of four concentrator targets. Within a month, the team had imaged more than 10,000 fragments and packed them for transport to the Astromaterials Acquisition and Curation Office within the ARES Directorate at JSC. Currently, the Genesis samples are curated along with the other extraterrestrial sample collections within ARES. Although they were broken and dirty, the Genesis solar wind collectors still offered the science community the opportunity to better understand our Sun and the solar system as a whole. One of the more highly prized concentrator collectors survived the crash almost completely intact. The Genesis Concentrator was designed to concentrate the solar wind by a factor of at least 20 so that solar oxygen and nitrogen isotopes could be measured. One of these materials was the Diamond-on-Silicon (DoS) concentrator target. Unfortunately, the DoS concentrator broke on impact. Nevertheless, the scientific value of the DoS concentrator target was high. The Genesis Allocation Committee received a request for approximately 1 cm(sup 2) of the DoS specimen taken near the focal point of the concentrator for the analysis of solar wind nitrogen isotopes. The largest fragment, Genesis sample 60000, was designated for this allocation and needed to be precisely cut. The requirement was to subdivide the designated sample in a manner that prevented contamination of the sample and minimized the risk of losing or breaking the precious requested sample fragment. The Genesis curator determined that the use of laser scribing techniques to "cut" a precise line and subsequently cleave the sample (in a controlled break of the sample along that line) was the best method for accomplishing the sample subdivision. However, there were risks, including excess heating of the sample, that could cause some of the implanted solar wind to be lost via thermal diffusion. Accidentally breaking the sample during the handling and cleaving process was an additional risk. Early in fiscal year 2013, to address this delicate, complicated task, the ARES Directorate assembled its top scientists to develop a cutting plan that would ensure success when applied to the actual concentrator target wafer; i.e., to produce an approximately 1 cm(sup 2) piece from the requested area of the wafer. The team, subsequently referred to as the JSC Genesis Tiger Team, spent months researching and testing parameters and techniques related to scribing, cleaving, transporting, handling, and holding (i.e., mounting) the specimen. The investigation required considerable "thinking outside the box," and many, many trials using nonflight wafer analogs. After all preliminary testing, the following method was adopted as the final cutting plan. It was used in two final end-to-end practice runs before being used on the actual flight target wafer. The wafer was oriented on the laser cutting stage with the 100 and 010 directions of the wafer parallel to the corresponding X and Y directions of the cutting stage. The laser was programed to scribe 31 lines of the appropriate length along the Y stage direction. The programed scribe lines were separated by 5 micron in the X direction. The laser parameters were set as follows: (1) The laser power was 0.5 watts; (2) each line consisted of 50 passes, with the Z position being advanced 5 micron per pass; and (3) 30 s would elapse before the next line was scribed to allow for wafer cool down from any possible heating via the laser. The ablated material that "stuck" in the "scribe-cut" was removed from the "cut" using an ultrasonic micro-tool. After all the ablated silicon was removed from the wafer, the wafer was repositioned in exactly the same orientation on the laser stage. The laser was focused using the bottom of the wafer channel, and the 31-line scribing pattern described above was reprogrammed using the Z position of the groove bottom as the starting Z value instead of the top wafer surface, which was used previously. Upon completion of the second set of scribes, the ultrasonic micro-tool was again used to clean out the cut. The wafer was remounted on the stage in exactly the same orientation as before. The laser was again focused on the bottom of the groove. This time, however, the laser was.programed to scribe only one line down the exact center of the channel. The final scribe line consisted of 100 passes with a Z advance of 5 micron per pass and with the laser power set at 0.5 watts. As mentioned above, the final cutting plan was practiced in two end-to-end trials using non-flight, triangular-shaped silicon wafers similar in size and orientation to the actual DOS 60000 target sample. The actual scribing of the triangular-shaped wafers required scribing two lines and cleaving (i.e. scribe-cleave, then scribe-cleave) to obtain the piece requested for allocation. Early in December 2012, after many months of experiments and practicing and perfecting the techniques and procedures, the team successfully subdivided the Genesis DoS 60000 target sample, one of the most scientifically important samples from the Genesis mission (figure 2). On December 17, 2012, the allocated piece of concentrator target sample was delivered to the requesting principal investigator.The cutting plan developed for the subdivision of this sample will be used as the model for subdividing future requested Genesis flight wafers (appropriately modified for different wafer types).

  17. Negative pressure of the environmental air in the cleaning area of the materials and sterilization center: a systematic review.

    PubMed

    Ciofi-Silva, Caroline Lopes; Hansen, Lisbeth Lima; Almeida, Alda Graciele Claudio Dos Santos; Kawagoe, Julia Yaeko; Padoveze, Maria Clara; Graziano, Kazuko Uchikawa

    2016-09-01

    to analyze the scientific evidence on aerosols generated during cleaning activities of health products in the Central Service Department (CSD) and the impact of the negative pressure of the ambient air in the cleaning area to control the dispersion of aerosols to adjacent areas. for this literature systematic review the following searches were done: search guidelines, manuals or national and international technical standards given by experts; search in the portal and databases PubMed, Scopus, CINAHL and Web of Science; and a manual search of scientific articles. the five technical documents reviewed recommend that the CSD cleaning area should have a negative differential ambient air pressure, but scientific articles on the impact of this intervention were not found. The four articles included talked about aerosols formed after the use of a ultrasonic cleaner (an increased in the contamination especially during use) and pressurized water jet (formation of smaller aerosols 5μm). In a study, the aerosols formed from contaminated the hot tap water with Legionella pneumophila were evaluated. there is evidence of aerosol formation during cleanup activities in CSD. Studies on occupational diseases of respiratory origin of workers who work in CSD should be performed. analisar as evidências científicas sobre aerossóis gerados durante atividades de limpeza dos produtos para saúde no Centro de Material e Esterilização (CME) e o impacto da pressão negativa do ar ambiente na área de limpeza para controle da dispersão de aerossóis para áreas adjacentes. para essa revisão sistemática de literatura foram realizadas: busca de diretrizes, manuais ou normas técnicas nacionais e internacionais indicadas por especialistas; busca no portal e bases de dados PUBMED, SCOPUS, Cinahl e Web of Science; e busca manual de artigos científicos. Os cinco documentos técnicos analisados preconizam que na área de limpeza do CME haja diferencial negativo de pressão do ar ambiente, porém não foram encontrados artigos científicos sobre o impacto dessa intervenção. Os quatro artigos incluídos trataram dos aerossóis formados após uso de lavadora ultrassônica (aumento da contaminação principalmente durante o uso) e do jato de água pressurizado (formação de aerossóis menores que 5µm). Em um estudo foram avaliados aerossóis formados a partir de torneira de água quente contaminada com Legionella pneumophila. há evidências sobre formação de aerossóis durante atividades de limpeza em CME. Estudos sobre doenças ocupacionais de origem respiratória dos trabalhadores que atuam em CME devem ser realizados. examinar la evidencia científica sobre los aerosoles generados durante las actividades de limpieza de productos de salud en el Centro de Materiales y Esterilización (CME) y el impacto de la presión negativa del aire ambiente en la zona de limpieza para controlar la dispersión de aerosoles a las zonas adyacentes. para esta revisión sistemática de literatura se llevaron a cabo: búsqueda de directrices, manuales o normas técnicas nacionales e internacionales impartidas por expertos; búsqueda en las bases de datos PUBMED, SCOPUS, Cinahl y Web of Science; y búsqueda manual de artículos científicos. Los cinco documentos técnicos analizados recomiendan que el área de limpieza del CME tenga un diferencial negativo de presión en el aire ambiente, aunque no se han encontrado artículos científicos sobre el impacto de esta intervención. Los cuatro artículos incluidos fueron sobre los aerosoles formados después del uso de la lavadora ultrasónica (aumento de la contaminación, especialmente durante el uso) y chorro de agua a presión (formación de aerosoles menores a 5µm). De esta forma, en un solo estudio se evaluaron los aerosoles formados a partir de un grifo de agua caliente contaminada con Legionella pneumophila. hay evidencia de formación de aerosoles durante las actividades de limpieza en CME. Sin embargo, es necesario realizar estudios sobre las enfermedades profesionales de origen respiratorio de los trabajadores que trabajan en CME.

  18. Noninvasive optical cytochrome c oxidase redox state measurements using diffuse optical spectroscopy

    PubMed Central

    Lee, Jangwoen; Kim, Jae G.; Mahon, Sari B.; Mukai, David; Yoon, David; Boss, Gerry R.; Patterson, Steven E.; Rockwood, Gary; Isom, Gary; Brenner, Matthew

    2014-01-01

    Abstract. A major need exists for methods to assess organ oxidative metabolic states in vivo. By contrasting the responses to cyanide (CN) poisoning versus hemorrhage in animal models, we demonstrate that diffuse optical spectroscopy (DOS) can detect cytochrome c oxidase (CcO) redox states. Intermittent decreases in inspired O2 from 100% to 21% were applied before, during, and after CN poisoning, hemorrhage, and resuscitation in rabbits. Continuous DOS measurements of total hemoglobin, oxyhemoglobin, deoxyhemoglobin, and oxidized and reduced CcO from muscle were obtained. Rabbit hemorrhage was accomplished with stepwise removal of blood, followed by blood resuscitation. CN treated rabbits received 0.166  mg/min NaCN infusion. During hemorrhage, CcO redox state became reduced concurrently with decreases in oxyhemoglobin, resulting from reduced tissue oxygen delivery and hypoxia. In contrast, during CN infusion, CcO redox state decreased while oxyhemoglobin concentration increased due to CN binding and reduction of CcO with resultant inhibition of the electron transport chain. Spectral absorption similarities between hemoglobin and CcO make noninvasive spectroscopic distinction of CcO redox states difficult. By contrasting physiological perturbations of CN poisoning versus hemorrhage, we demonstrate that DOS measured CcO redox state changes are decoupled from hemoglobin concentration measurement changes. PMID:24788369

  19. Multi-distance diffuse optical spectroscopy with a single optode via hypotrochoidal scanning.

    PubMed

    Applegate, Matthew B; Roblyer, Darren

    2018-02-15

    Frequency-domain diffuse optical spectroscopy (FD-DOS) is an established technique capable of determining optical properties and chromophore concentrations in biological tissue. Most FD-DOS systems use either manually positioned, handheld probes or complex arrays of source and detector fibers to acquire data from many tissue locations, allowing for the generation of 2D or 3D maps of tissue. Here, we present a new method to rapidly acquire a wide range of source-detector (SD) separations by mechanically scanning a single SD pair. The source and detector fibers are mounted on a scan head that traces a hypotrochoidal pattern over the sample that, when coupled with a high-speed FD-DOS system, enables the rapid collection of dozens of SD separations for depth-resolved imaging. We demonstrate that this system has an average error of 4±2.6% in absorption and 2±1.8% in scattering across all SD separations. Additionally, by linearly translating the device, the size and location of an absorbing inhomogeneity can be determined through the generation of B-scan images in a manner conceptually analogous to ultrasound imaging. This work demonstrates the potential of single optode diffuse optical scanning for depth resolved visualization of heterogeneous biological tissues at near real-time rates.

  20. Quantum oscillations in vortex-liquids

    NASA Astrophysics Data System (ADS)

    Banerjee, Sumilan; Zhang, Shizhong; Randeria, Mohit

    2012-02-01

    Motivated by observations of quantum oscillations in underdoped cuprates [1], we examine the electronic density of states (DOS) in a vortex-liquid state, where long-range phase coherence is destroyed by an external magnetic field H but the local pairing amplitude survives. We note that this regime is distinct from that studied in most of the recent theories, which have focused on either a Fermi liquid with a competing order parameter or on a d-wave vortex lattice. The cuprate experiments are very likely in a resistive vortex-liquid state. We generalize the s-wave analysis of Maki and Stephen [2] to d-wave pairing and examine various regimes of the chemical potential, gap and field. We find that the (1/H) oscillations of the DOS at the chemical potential in a d-wave vortex-liquid are much more robust, i.e., have a reduced damping, compared to the s-wave case. We critically investigate the conventional wisdom relating the observed frequency to the area of an underlying Fermi surface. We also show that the oscillations in the DOS cross over to a √H behavior in the low field limit, in agreement with the recent specific heat measurements. [1] L. Taillefer, J. Phys. Cond. Mat. 21, 164212 (2009). [2] M. J. Stephen, Phys. Rev. B 45, 5481 (1992).

  1. Noninvasive optical cytochrome c oxidase redox state measurements using diffuse optical spectroscopy

    NASA Astrophysics Data System (ADS)

    Lee, Jangwoen; Kim, Jae G.; Mahon, Sari B.; Mukai, David; Yoon, David; Boss, Gerry R.; Patterson, Steven E.; Rockwood, Gary; Isom, Gary; Brenner, Matthew

    2014-05-01

    A major need exists for methods to assess organ oxidative metabolic states in vivo. By contrasting the responses to cyanide (CN) poisoning versus hemorrhage in animal models, we demonstrate that diffuse optical spectroscopy (DOS) can detect cytochrome c oxidase (CcO) redox states. Intermittent decreases in inspired O2 from 100% to 21% were applied before, during, and after CN poisoning, hemorrhage, and resuscitation in rabbits. Continuous DOS measurements of total hemoglobin, oxyhemoglobin, deoxyhemoglobin, and oxidized and reduced CcO from muscle were obtained. Rabbit hemorrhage was accomplished with stepwise removal of blood, followed by blood resuscitation. CN treated rabbits received 0.166 mg/min NaCN infusion. During hemorrhage, CcO redox state became reduced concurrently with decreases in oxyhemoglobin, resulting from reduced tissue oxygen delivery and hypoxia. In contrast, during CN infusion, CcO redox state decreased while oxyhemoglobin concentration increased due to CN binding and reduction of CcO with resultant inhibition of the electron transport chain. Spectral absorption similarities between hemoglobin and CcO make noninvasive spectroscopic distinction of CcO redox states difficult. By contrasting physiological perturbations of CN poisoning versus hemorrhage, we demonstrate that DOS measured CcO redox state changes are decoupled from hemoglobin concentration measurement changes.

  2. Comparison of cobinamide to hydroxocobalamin in reversing cyanide physiologic effects in rabbits using diffuse optical spectroscopy monitoring

    NASA Astrophysics Data System (ADS)

    Brenner, Matthew; Mahon, Sari B.; Lee, Jangwoen; Kim, Jae; Mukai, David; Goodman, Seth; Kreuter, Kelly A.; Ahdout, Rebecca; Mohammad, Othman; Sharma, Vijay S.; Blackledge, William; Boss, Gerry R.

    2010-01-01

    Our purpose is to compare cobinamide to hydroxocobalamin in reversing cyanide (CN)-induced physiologic effects in an animal model using diffuse optical spectroscopy (DOS). Cyanide poisoning is a major threat worldwide. Cobinamide is a novel molecule that can bind two molecules of cyanide, has a much higher binding affinity than hydroxocobalamin, and is more water soluble. We investigated the ability of equimolar doses of cobinamide and hydroxocobalamin to reverse the effects of cyanide exposure in an animal model monitored continuously by DOS. Cyanide toxicity was induced in 16 New Zealand white rabbits by intravenous infusion. Animals were divided into three groups: controls (n=5) received saline following cyanide, hydroxocobalamin (N=6) following cyanide, and cobinamide (N=5) following cyanide. Cobinamide caused significantly faster and more complete recovery of oxy- and deoxyhemoglobin concentrations in cyanide-exposed animals than hydroxocobalamin- or saline-treated animals, with a recovery time constant of 13.8+/-7.1 min compared to 75.4+/-25.1 and 76.4+/-42.7 min, for hydroxocobalamin- and saline-treated animals, respectively (p<0.0001). This study indicates that cobinamide more rapidly and completely reverses the physiologic effects of cyanide than equimolar doses of cobalamin at the dose used in this study, and CN effects and response can be followed noninvasively using DOS.

  3. Trends in chemical ecology revealed with a personal computer program for searching data bases of scientific references and abstracts.

    PubMed

    Byers, J A

    1992-09-01

    A compiled program, JCE-REFS.EXE (coded in the QuickBASIC language), for use on IBM-compatible personal computers is described. The program converts a DOS text file of current B-I-T-S (BIOSIS Information Transfer System) or BIOSIS Previews references into a DOS file of citations, including abstracts, in a general style used by scientific journals. The latter file can be imported directly into a word processor or the program can convert the file into a random access data base of the references. The program can search the data base for up to 40 text strings with Boolean logic. Selected references in the data base can be exported as a DOS text file of citations. Using the search facility, articles in theJournal of Chemical Ecology from 1975 to 1991 were searched for certain key words in regard to semiochemicals, taxa, methods, chemical classes, and biological terms to determine trends in usage over the period. Positive trends were statistically significant in the use of the words: semiochemical, allomone, allelochemic, deterrent, repellent, plants, angiosperms, dicots, wind tunnel, olfactometer, electrophysiology, mass spectrometry, ketone, evolution, physiology, herbivore, defense, and receptor. Significant negative trends were found for: pheromone, vertebrates, mammals, Coleoptera, Scolytidae,Dendroctonus, lactone, isomer, and calling.

  4. Corrosion inhibition with different protective layers in tinplate cans for food preservation.

    PubMed

    Grassino, Antonela Ninčević; Grabarić, Zorana; Pezzani, Aldo; Squitieri, Giuseppe; Berković, Katarina

    2010-11-01

    In this work the influence of essential onion oil (EOO) on the protection of tinplates was compared with dioctyl sebacate oil (DOS) and epoxy phenolic lacquers, which are frequently used in the food canning industry. When EOO as the protective layer instead of DOS oil was used, tinplate porosity, measured electrochemically (7.58 ± 1.97 µA cm(-2) and 23.0 ± 1.3 µA cm(-2), respectively), and iron coating mass, calculated from AAS data (1.52 ± 0.15 mg m(-2) and 3.14 ± 0.42, respectively), was much lower indicating better corrosion protection. At higher storing temperature (36 °C) the addition of EOO to canned tomato purée enhanced the formation of hydrogen with time. The increasing volume fraction of H(2) (from 34.0 to 90.9% for cans without nitrates, and from 33.8 to 89.2% for cans with nitrates) is an indicator that corrosion takes place. As the use of EOO improves the protection of tinplate compared with DOS oil, and is almost as effective as epoxy phenolic lacquer, the addition of EOO can be recommended due to lower cost of canned food production and enhanced organoleptic properties, but the storage temperature has to be lower then 36 °C. 2010 Society of Chemical Industry

  5. Perfil de temperatura dos funis magnetosféricos de estrelas T Tauri com aquecimento alfvênico

    NASA Astrophysics Data System (ADS)

    Vasconcelos, M. J.

    2003-08-01

    Estrelas T Tauri Clássicas são objetos jovens circundados por discos de gás e poeira e que apresentam uma intensa atividade magnética. Seu espectro mostra linhas de emissão alargadas que são razoavelmente reproduzidas nos modelos de acresção magnetosférica. No entanto, o perfil de temperatura dos funis magnéticos é desconhecido. Aquecimento magnético compressional e difusão ambipolar foram considerados para estas estruturas, porém as temperaturas obtidas não são suficientes para explicar as observações. Neste trabalho, examinamos o aquecimento gerado pelo amortecimento de ondas Alfvén através de quatro mecanismos, os amortecimentos não-linear, turbulento, viscoso-resistivo e colisional como função da freqüência da onda. Inicialmente, a temperatura é ajustada para reproduzir as observações e o grau de turbulência requerido para que o mecanismo seja viável é calculado. Os resultados mostram que este é compatível com os dados observacionais. Apresentam-se, também, resultados preliminares do cálculo auto-consistente do perfil de temperatura dos funis, levando-se em conta fontes de aquecimento Alfvênica e fontes de resfriamento.

  6. Time differences in the formation of meteorites as determined from the ratio of lead-207 to lead-206

    USGS Publications Warehouse

    Tatsumoto, M.; Knight, R.J.; Allegre, C.J.

    1973-01-01

    Measurements of the lead isotopic composition and the uranium, thorium, and lead concentrations in meteorites were made in order to obtain more precise radiometric ages of these members of the solar system. The newly determined value of the lead isotopic composition of Canyon Diablo troilite is as follows: 206Pb/204Pb = 9.307, 207Pb/204Pb = 10.294, and 208Pb/204Pb = 29.476. The leads of Angra dos Reis, Sioux County, and Nuevo Laredo achondrites are very radiogenic, the 206Pb/204Pb values are about 200, and the uranium-thorium-lead systems are nearly concordant. The ages of the meteorites as calculated from a single-stage 207Pb/206Pb isochron based on the newly determined primordial lead value and the newly reported 235U and 238U decay constants, are 4.528 ?? 10 9 years for Sioux County and Nuevo Laredo and 4.555 ?? 10 9 years for Angra dos Reis. When calculated with the uranium decay constants used by Patterson, these ages are 4.593 ?? 109 years and 4.620 ?? 109 years, respectively, and are therefore 40 to 70 ?? 106 years older than the 4.55 ?? 109 years age Patterson reported. The age difference of 27 ?? 106 years between Angra dos Reis and the other two meteorites is compatible with the difference between the initial 87Sr/86Sr ratio of Angra dos Reis and that of seven basaltic achondrites observed by Papanastassiou and Wasserburg. The time difference is also comparable to that determined by 129I-129Xe chronology. The ages of ordinary chondrites (H5 and L6) range from 4.52 to 4.57 ?? 109 years, and, here too, time differences in the formation of the parent bodies or later metamorphic events are indicated. Carbonaceous chondrites (C2 and C3) appear to contain younger lead components.

  7. BSSDATA - um programa otimizado para filtragem de dados em radioastronomia solar

    NASA Astrophysics Data System (ADS)

    Martinon, A. R. F.; Sawant, H. S.; Fernandes, F. C. R.; Stephany, S.; Preto, A. J.; Dobrowolski, K. M.

    2003-08-01

    A partir de 1998, entrou em operação regular no INPE, em São José dos Campos, o Brazilian Solar Spectroscope (BSS). O BSS é dedicado às observações de explosões solares decimétricas com alta resolução temporal e espectral, com a principal finalidade de investigar fenômenos associados com a liberação de energia dos "flares" solares. Entre os anos de 1999 e 2002, foram catalogadas, aproximadamente 340 explosões solares classificadas em 8 tipos distintos, de acordo com suas características morfológicas. Na análise detalhada de cada tipo, ou grupo, de explosões solares deve-se considerar a variação do fluxo do sol calmo ("background"), em função da freqüência e a variação temporal, além da complexidade das explosões e estruturas finas registradas superpostas ao fundo variável. Com o intuito de realizar tal análise foi desenvolvido o programa BSSData. Este programa, desenvolvido em linguagem C++, é constituído de várias ferramentas que auxiliam no tratamento e análise dos dados registrados pelo BSS. Neste trabalho iremos abordar as ferramentas referentes à filtragem do ruído de fundo. As rotinas do BSSData para filtragem de ruído foram testadas nos diversos grupos de explosões solares ("dots", "fibra", "lace", "patch", "spikes", "tipo III" e "zebra") alcançando um bom resultado na diminuição do ruído de fundo e obtendo, em conseqüência, dados onde o sinal torna-se mais homogêneo ressaltando as áreas onde existem explosões solares e tornando mais precisas as determinações dos parâmetros observacionais de cada explosão. Estes resultados serão apresentados e discutidos.

  8. Rare-Region-Induced Avoided Quantum Criticality in Disordered Three-Dimensional Dirac and Weyl Semimetals

    NASA Astrophysics Data System (ADS)

    Pixley, J. H.; Huse, David A.; Das Sarma, S.

    2016-04-01

    We numerically study the effect of short-ranged potential disorder on massless noninteracting three-dimensional Dirac and Weyl fermions, with a focus on the question of the proposed (and extensively theoretically studied) quantum critical point separating semimetal and diffusive-metal phases. We determine the properties of the eigenstates of the disordered Dirac Hamiltonian (H ) and exactly calculate the density of states (DOS) near zero energy, using a combination of Lanczos on H2 and the kernel polynomial method on H . We establish the existence of two distinct types of low-energy eigenstates contributing to the disordered density of states in the weak-disorder semimetal regime. These are (i) typical eigenstates that are well described by linearly dispersing perturbatively dressed Dirac states and (ii) nonperturbative rare eigenstates that are weakly dispersive and quasilocalized in the real-space regions with the largest (and rarest) local random potential. Using twisted boundary conditions, we are able to systematically find and study these two (essentially independent) types of eigenstates. We find that the Dirac states contribute low-energy peaks in the finite-size DOS that arise from the clean eigenstates which shift and broaden in the presence of disorder. On the other hand, we establish that the rare quasilocalized eigenstates contribute a nonzero background DOS which is only weakly energy dependent near zero energy and is exponentially small at weak disorder. We also find that the expected semimetal to diffusive-metal quantum critical point is converted to an avoided quantum criticality that is "rounded out" by nonperturbative effects, with no signs of any singular behavior in the DOS at the energy of the clean Dirac point. However, the crossover effects of the avoided (or hidden) criticality manifest themselves in a so-called quantum critical fan region away from the Dirac energy. We discuss the implications of our results for disordered Dirac and Weyl semimetals, and reconcile the large body of existing numerical work showing quantum criticality with the existence of these nonperturbative effects.

  9. Determinação da massa de júpiter a partir das órbitas de seus satélites: um experimento didático

    NASA Astrophysics Data System (ADS)

    Schlickmann, M. S.; Saito, R. K.; Becker, D. A.; Rezende, M. F., Jr.; Cid Fernandes, R.

    2003-08-01

    Este trabalho apresenta o roteiro piloto de uma prática observacional em astronomia, junto com os primeiros resultados obtidos nesta fase de implementacão. O projeto, que será executado em duas etapas, visa introduzir noções de Astronomia a alunos do Ensino Médio e iniciantes nos cursos de Física. O experimento consiste em medir as órbitas dos satélites Galileanos e, a partir da análise dos dados coletados, verificar a validade da Lei das órbitas de Kepler, determinando a massa do planeta Júpiter. Em uma primeira etapa, as observações serão feitas utilizando um telescópio Meade LX200 10" e câmera CCD para obter uma seqüência de imagens do planeta, que possibilitará medir o movimento de seus satélites. A segunda etapa terá início a partir do funcionamento do telescópio em modo robótico, com a possibilidade de observações via internet por instituições de ensino. Para o desenvolvimento deste experimento foram inicialmente coletadas várias imagens de Júpiter obtidas com os instrumentos citados acima. Estas imagens serviram como base para confecção dos roteiros para a experiência no nível médio e superior. Os roteiros serão inicialmente apresentados em uma home-page. Nela também se buscará uma contextualização histórica da experiência bem como o estabelecimento de relações com professores e alunos, propostas metodológicas e a disponibilização dos programas computacionais necessários para a utilização "on-line" pelos usuários. O projeto conta com apoio da Fundação VITAE.

  10. Astronomia Motivadora no Ensino Fundamental

    NASA Astrophysics Data System (ADS)

    Melo, J.; Voelzke, M. R.

    2008-09-01

    O objetivo principal deste trabalho é procurar desenvolver o interesse dos alunos pelas ciências através da Astronomia. Uma pesquisa com perguntas sobre Astronomia foi realizada junto a 161 alunos do Ensino Fundamental, com o intuito de descobrir conhecimentos prévios dos alunos sobre o assunto. Constatou-se, por exemplo, que 29,3% da 6ª série responderam corretamente o que é eclipse, 30,0% da 8ª série acertaram o que a Astronomia estuda, enquanto 42,3% dos alunos da 5ª série souberam definir o Sol. Pretende-se ampliar as turmas participantes e trabalhar, principalmente de forma prática com: dimensões e escalas no Sistema Solar, construção de luneta, questões como dia e noite, estações do ano e eclipses. Busca-se abordar, também, outros conteúdos de Física tais como a óptica na construção da luneta, e a mecânica no trabalho com escalas e medidas, e ao utilizar uma luminária para representar o Sol na questão do eclipse, e de outras disciplinas como a Matemática na transformação de unidades, regras de três; Artes na modelagem ou desenho dos planetas; a própria História com relação à busca pela origem do universo, e a Informática que possibilita a busca mais rápida por informações, além de permitir simulações e visualizações de imagens importantes. Acredita-se que a Astronomia é importante no processo ensino aprendizagem, pois permite a discussão de temas curiosos como, por exemplo, a origem do universo, viagens espaciais a existência ou não de vida em outros planetas, além de temas atuais como as novas tecnologias.

  11. Escleroterapia de safena associada a enxerto de pele no tratamento de úlceras venosas

    PubMed Central

    de Oliveira, Alexandre Faraco; de Oliveira, Horácio

    2017-01-01

    Resumo Contexto Úlceras são a resultante final de varizes associadas a refluxo de veias safenas. Objetivo Demonstrar a possibilidade de associar dois procedimentos, a escleroterapia com espuma de veias safenas e o enxerto de pele parcial, para o tratamento de pacientes com úlceras venosas relacionadas a refluxo de veias safenas. Métodos Foram tratados 20 membros em 20 pacientes, todos com ulcerações relacionadas a refluxo de veias safenas. Realizamos o enxerto de pele expandida, seguido da escleroterapia ecoguiada com espuma de polidocanol nas veias associadas às úlceras, através de punção ou dissecção da veia. Resultados Em todos os casos, houve melhora dos sintomas relacionados à úlcera e cicatrização da lesão. Em 11 casos, obtivemos a viabilidade do enxerto de pele por completo; em quatro casos, houve cicatrização de cerca de 50% da lesão; e nos cinco casos restantes, houve cicatrização de aproximadamente 75% da lesão. A primeira ultrassonografia de controle revelou esclerose completa dos vasos tratados em 19 dos 20 casos e esclerose parcial sem refluxo detectável em um caso. Na segunda ultrassonografia, realizada após 45 dias, observamos esclerose completa de 15 casos; em cinco casos, houve esclerose parcial, dos quais três sem refluxo detectável e dois com refluxo em segmentos isolados associados a varizes. A complicação mais frequente foi a pigmentação nos trajetos venosos, observada em 13 pacientes. Um caso apresentou trombose assintomática de veias musculares da perna. Conclusão Essa associação de procedimentos consiste em uma opção válida com potencial para promover um tratamento mais breve e de menor custo. PMID:29930660

  12. ELM - A SIMPLE TOOL FOR THERMAL-HYDRAULIC ANALYSIS OF SOLID-CORE NUCLEAR ROCKET FUEL ELEMENTS

    NASA Technical Reports Server (NTRS)

    Walton, J. T.

    1994-01-01

    ELM is a simple computational tool for modeling the steady-state thermal-hydraulics of propellant flow through fuel element coolant channels in nuclear thermal rockets. Written for the nuclear propulsion project of the Space Exploration Initiative, ELM evaluates the various heat transfer coefficient and friction factor correlations available for turbulent pipe flow with heat addition. In the past, these correlations were found in different reactor analysis codes, but now comparisons are possible within one program. The logic of ELM is based on the one-dimensional conservation of energy in combination with Newton's Law of Cooling to determine the bulk flow temperature and the wall temperature across a control volume. Since the control volume is an incremental length of tube, the corresponding pressure drop is determined by application of the Law of Conservation of Momentum. The size, speed, and accuracy of ELM make it a simple tool for use in fuel element parametric studies. ELM is a machine independent program written in FORTRAN 77. It has been successfully compiled on an IBM PC compatible running MS-DOS using Lahey FORTRAN 77, a DEC VAX series computer running VMS, and a Sun4 series computer running SunOS UNIX. ELM requires 565K of RAM under SunOS 4.1, 360K of RAM under VMS 5.4, and 406K of RAM under MS-DOS. Because this program is machine independent, no executable is provided on the distribution media. The standard distribution medium for ELM is one 5.25 inch 360K MS-DOS format diskette. ELM was developed in 1991. DEC, VAX, and VMS are trademarks of Digital Equipment Corporation. Sun4 and SunOS are trademarks of Sun Microsystems, Inc. IBM PC is a registered trademark of International Business Machines. MS-DOS is a registered trademark of Microsoft Corporation.

  13. The development of communication skills and the teacher's performance in the nursing student's perspective.

    PubMed

    Oliveira, Karime Rodrigues Emilio de; Braga, Eliana Mara

    2016-06-01

    To understand experiences in the development of communication skills and the teacher's role in this teaching-learning process under the perspective of undergraduate nursing students by considering two types of curriculum organization. Descriptive study with a qualitative approach conducted in two public schools located in São Paulo state, Brazil. Data were collected by means of self-completed forms from 81 students in the second and fourth years of the undergraduate program. Results were analyzed in light of Content Analysis. Results showed that the development of such skills is related to: students' individual characteristics, patients' characteristics, those of the health-disease process, the health-care team's profile and the theoretical knowledge acquired on communication in health-care provision and nursing. The teacher's role was perceived as one that supports and encourages interactions with patients and health-care teams by teaching and providing orientation about interpersonal communication. Students identify and value the importance of their teachers' performance in the development and acquisition of communication skills. Additionally, students who experience active teaching-learning methodologies acknowledge the teacher as essential to provide opportunities for students to express their knowledge and thoughts. Compreender, sob a ótica de graduandos de enfermagem, as experiências no desenvolvimento de habilidades comunicativas e a atuação do professor neste processo de ensino-aprendizagem, considerando dois tipos de organização curricular. Pesquisa descritiva com abordagem qualitativa, realizada em duas instituições de ensino públicas, situadas no interior do estado de São Paulo, Brasil. A coleta dos dados foi realizada pelo autopreenchimento de formulário por 81 alunos de segundo e quartos anos da graduação. Os resultados foram analisados à luz da Análise de Conteúdo. Revelaram que o desenvolvimento desta habilidade está relacionado à: características individuais dos alunos, dos pacientes, do processo saúde-doença, perfil da equipe e dos conhecimentos teóricos sobre comunicação em saúde e em enfermagem. O papel do professor foi percebido apoiando e incentivando as interações com pacientes e equipes de saúde e ensinando e orientando sobre comunicação interpessoal. Os alunos identificam e valorizam a importância da atuação de seus professores no desenvolvimento e aquisição de habilidades comunicativas. Além disso, os estudantes que vivenciaram as metodologias ativas de ensino-aprendizagem reconhecem o docente essencial para oportunizar a expressão de conhecimentos e pensamentos dos alunos.

  14. Use of Remote Sensing and Local Knowledge for Geoconservation of Regiao dos Lagos, Brazil

    NASA Astrophysics Data System (ADS)

    Avelar, S.; Vasconcelos, G.; Mansur, K. L.; Anjos, S. C.

    2013-12-01

    A series of lagoons can be found along the coastline of Rio de Janeiro, in the so-called Regiao dos Lagos. The lagoons differ in size, physicochemical, sedimentological and biological characteristics. Rare examples of litifying microbialites that produce stromatolites, the oldest fossils on Earth, can be found living in this lagoon system. The occurrence of stromatolites in the region is of great scientific interest because it enables the study of possible analogues of the earliest life on Earth. However, this region has been suffering from intense human activities and degradations. Geoconservation planning requires an assessment of the characteristics of the region and its potential threats. The primary goal of this study is to assess physical environmental changes and anthropogenic impacts over the last four decades in Regiao dos Lagos. Using a broad integrative assessment combining remote sensing, GIS, field studies and local knowledge of communities, land-cover and land-use classes were identified, as well as the main human activities impacting the environment. The seasonal and weekend tourism and urban sprawl in this coastal area of Rio de Janeiro triggers the occupation of new areas and the removal of natural vegetation, especially on lagoon margins. This disorderly occupation by an ever increasing population, with both legal and illegal constructions and the subsequent overload of the local infrastructure, e.g. increase of electrical energy consumption, volume of vehicles, pollution in air, water and soil and problems with water supply and wastewater treatment, are hastening the gradual degradation of the lake ecosystem. The main driving forces to environmental changes over the last four decades in Regiao dos Lagos were the change of dense vegetation, saline and bare soil classes into built-up areas, adding to the poor waste treatment and inadequate sewage disposal. This analysis provides a basis for a better control of anthropogenic impacts and geoconservation activities of the ';Geopark Costoes e Lagunas do Rio de Janeiro', which includes Regiao dos Lagos. The goals of the geopark are the conservation of a healthy environment, education in the Earth sciences and the fostering of local, sustainable economic development. It is essential that the local government and population support the geoconservation work and are involved in the planning and implementation of activities. The local knowledge about natural, cultural and economical particularities of the region and awareness on environmental issues are taken into consideration, in order to assist the development of specific geoconservation activities according to community needs.

  15. RSM 1.0 - A RESUPPLY SCHEDULER USING INTEGER OPTIMIZATION

    NASA Technical Reports Server (NTRS)

    Viterna, L. A.

    1994-01-01

    RSM, Resupply Scheduling Modeler, is a fully menu-driven program that uses integer programming techniques to determine an optimum schedule for replacing components on or before the end of a fixed replacement period. Although written to analyze the electrical power system on the Space Station Freedom, RSM is quite general and can be used to model the resupply of almost any system subject to user-defined resource constraints. RSM is based on a specific form of the general linear programming problem in which all variables in the objective function and all variables in the constraints are integers. While more computationally intensive, integer programming was required for accuracy when modeling systems with small quantities of components. Input values for component life cane be real numbers, RSM converts them to integers by dividing the lifetime by the period duration, then reducing the result to the next lowest integer. For each component, there is a set of constraints that insure that it is replaced before its lifetime expires. RSM includes user-defined constraints such as transportation mass and volume limits, as well as component life, available repair crew time and assembly sequences. A weighting factor allows the program to minimize factors such as cost. The program then performs an iterative analysis, which is displayed during the processing. A message gives the first period in which resources are being exceeded on each iteration. If the scheduling problem is unfeasible, the final message will also indicate the first period in which resources were exceeded. RSM is written in APL2 for IBM PC series computers and compatibles. A stand-alone executable version of RSM is provided; however, this is a "packed" version of RSM which can only utilize the memory within the 640K DOS limit. This executable requires at least 640K of memory and DOS 3.1 or higher. Source code for an APL2/PC workspace version is also provided. This version of RSM can make full use of any installed extended memory but must be run with the APL2 interpreter; and it requires an 80486 based microcomputer or an 80386 based microcomputer with an 80387 math coprocessor, at least 2Mb of extended memory, and DOS 3.3 or higher. The standard distribution medium for this package is one 5.25 inch 360K MS-DOS format diskette. RSM was developed in 1991. APL2 and IBM PC are registered trademarks of International Business Machines Corporation. MS-DOS is a registered trademark of Microsoft Corporation.

  16. Telescópio de pequeno porte como suporte ao ensino em cidades com intensa poluição luminosa II

    NASA Astrophysics Data System (ADS)

    Pereira, P. C. R.; Santos-Júnior, J. M.; Cruz, W. S.

    2003-08-01

    Para a maioria dos estudantes, sua passagem pelo ensino formal fundamental envolve a transmissão de fatos que devem ser guardados para um exame, a habilidade para lembrar fórmulas e, eventualmente, a repetição de experimentos que devem produzir resultados exigidos pelo professor. O resultado deste modelo de ensino, ao longo dos anos, é conhecido por todos: desconhecimento e descontentamento, por parte dos estudantes, de temas relativos ao papel e aos processos da ciência. Acreditamos que a Astronomia, pelo seu caráter observacional, é uma das áreas do conhecimento que pode contribuir neste cenário. A Fundação Planetário da Cidade do Rio de Janeiro possui um telescópio Meade LX-200 (25cm) que, juntamente com as câmeras CCD ST-7E e ST8E, tem sido utilizado em projetos voltados aos estudantes do ensino médio desde o ano 2000. Tais projetos envolvem a condução de um projeto de pesquisa observacional num nível apropriado, e possibilitam o contato com técnicas e novas tecnologias: computador, software para manipulação de dados e gráficos, programas de tratamento e redução de dados, uso de equipamentos óptico-eletrônicos (telescópio e CCD), bem como o processo de aquisição de conhecimento. Dentro da proposta dos anos anteriores, priorizamos projetos de uma noite, ou seja, procuramos trabalhar com fenômenos que apresentem variabilidade com intervalo de recorrência relativamente curto. Em todos os casos, optamos pela fotometria diferencial, que tem se mostrado bastante eficiente para o céu luminoso como o da cidade do Rio de Janeiro. Neste painel, apresentamos alguns dos projetos desenvolvidos no último ano, com 25 estudantes. Apresentamos os resultados da observação da variável pulsante AI Vel (V = 6,6) e da variável cataclísmica FO Aqr (V = 13,5), e do monitoramento do trânsito da lua de Júpiter, Europa, ocorrido em 30 de abril de 2003. As curvas de luz produzidas para as primeiras estão concordantes com as da literatura, assim como os respectivos períodos encontrados (1h20min e 4h48min). No caso do FO Aqr, ficou evidente, também, a modulação decorrente da rotação da anã branca receptora (21min). O erro estimado é de 0,01 magnitude. Propomos uma maior utilização de telescópios de pequeno porte, como suporte ao ensino (médio e superior) em cidades com poluição luminosa. Escolas e Planetários seriam ambientes propícios para a localização do telescópio. Os critérios adotados na escolha dos objetos e o método observacional empregado são também apresentados.

  17. Transport processes in partially saturate concrete: Testing and liquid properties

    NASA Astrophysics Data System (ADS)

    Villani, Chiara

    The measurement of transport properties of concrete is considered by many to have the potential to serve as a performance criterion that can be related to concrete durability. However, the sensitivity of transport tests to several parameters combined with the low permeability of concrete complicates the testing. Gas permeability and diffusivity test methods are attractive due to the ease of testing, their non-destructive nature and their potential to correlate to in-field carbonation of reinforced concrete structures. This work was aimed at investigating the potential of existing gas transport tests as a way to reliably quantify transport properties in concrete. In this study gas permeability and diffusivity test methods were analyzed comparing their performance in terms of repeatability and variability. The influence of several parameters was investigated such as moisture content, mixture proportions and gas flow. A closer look to the influence of pressure revealed an anomalous trend of permeability with respect to pressure. An alternative calculation is proposed in an effort to move towards the determination of intrinsic material properties that can serve as an input for service life prediction models. The impact of deicing salts exposure was also analyzed with respect to their alteration of the degree of saturation as this may affect gas transport in cementitious materials. Limited information were previously available on liquid properties over a wide range of concentrations. To overcome this limitation, this study quantified surface tension, viscosity in presence of deicing salts in a broad concentration range and at different temperatures. Existing models were applied to predict the change of fluid properties during drying. Vapor desorption isotherms were obtained to investigate the influence of deicing salts presence on the non-linear moisture diffusion coefficient. Semi-empirical models were used to quantify the initiation and the rate of drying using liquid properties and pore structure information as inputs. Concrete exposed to deicing salts resulted to have a reduced gas transport due to the higher degree of saturation (DOS). The higher DOS is believed to contribute to the premature deterioration observed in concrete pavements exposed to deicing salts. Moisture diffusion and moisture profiles in concrete are known to directly relate with the stresses generated during shrinkage and creep mechanisms. The alteration due to the presence of shrinkage reducing admixtures on drying was also investigated in this work. Liquid properties were used to predict the diffusion coefficient in presence of SRA. Moisture profiles obtained using Fick's second law for diffusion were compared to relative humidity profiles measured on concrete slabs. Results confirm that a qualitative prediction of drying in concrete elements is realistic when using this type of approach.

  18. Comparative study of abdominal cavity temporary closure techniques for damage control.

    PubMed

    Ribeiro, Marcelo A F; Barros, Emily Alves; Carvalho, Sabrina Marques DE; Nascimento, Vinicius Pereira; Cruvinel, José; Fonseca, Alexandre Zanchenko

    2016-01-01

    The damage control surgery, with emphasis on laparostomy, usually results in shrinkage of the aponeurosis and loss of the ability to close the abdominal wall, leading to the formation of ventral incisional hernias. Currently, various techniques offer greater chances of closing the abdominal cavity with less tension. Thus, this study aims to evaluate three temporary closure techniques of the abdominal cavity: the Vacuum-Assisted Closure Therapy - VAC, the Bogotá Bag and the Vacuum-pack. We conducted a systematic review of the literature, selecting 28 articles published in the last 20 years. The techniques of the bag Bogotá and Vacuum-pack had the advantage of easy access to the material in most centers and low cost, contrary to VAC, which, besides presenting high cost, is not available in most hospitals. On the other hand, the VAC technique was more effective in reducing stress at the edges of lesions, removing stagnant fluids and waste, in addition to acting at the cellular level by increasing proliferation and cell division rates, and showed the highest rates of primary closure of the abdominal cavity. RESUMO A cirurgia de controle de danos, com ênfase em peritoneostomia, geralmente resulta em retração da aponeurose e perda da capacidade de fechar a parede abdominal, levando à formação de hérnias ventrais incisionais. Atualmente, várias técnicas oferecem maiores chances de fechamento da cavidade abdominal, com menor tensão. Deste modo, este estudo tem por objetivo avaliar três técnicas de fechamento temporário da cavidade abdominal: fechamento a vácuo (Vacuum-Assisted Closure Therapy - VAC), Bolsa de Bogotá e Vacuum-pack. Realizou-se uma revisão sistemática da literatura com seleção de 28 artigos publicados nos últimos 20 anos. As técnicas de Bolsa de Bogotá e Vacuum-pack tiveram como vantagem o acesso fácil ao material, na maioria dos centros, e baixo custo, ao contrário do que se observa na terapia a vácuo, VAC, que além de apresentar alto custo, não está disponível em grande parte dos hospitais. A técnica VAC, por outro lado, foi mais eficaz na redução da tensão nas bordas das lesões, ao remover fluidos estagnados e detritos, além de exercer ação a nível celular, aumentando as taxas de proliferação e divisão celular, e apresentou as maiores taxas de fechamento primário da cavidade abdominal.

  19. Collagen, fibrinogen and thrombin biological addesive is effective in treating experimental liver injuries.

    PubMed

    Oliveira, Frederico Michelino DE; Carvalho, Marcus Vinícius H DE; Marchi, Evaldo; Pinto, Clóvis Antônio Lopes

    2016-01-01

    : to evaluate the effectiveness of a collagen-based adhesive associated with fibrinogen and thrombin in experimental liver injury in rats. : the study included 30 Wistar rats randomly divided into three groups: A, B and C. All underwent standard liver traumatic injury. In group A the lesion was treated with the adhesive; in group B, with conventional absorbable suture; and in group C, there was no treatment. We analyzed the time of hemostasis, mortality, occurrence of adhesions and any histological changes. : there was no statistical difference in relation to mortality (p = 0.5820). The group treated with the adhesive showed the lowest hemostasis times (p = 0.0573, odds ratio 13.5) and lower incidence of adhesions (p = 0.0119). Microscopic histological alterations of Groups A and B were similar, with foreign body granuloma formation separating the adhesive material or the suture from the hepatic stroma. : the adhesive of collagen associated with fibrinogen and thrombin was effective in the treatment of experimental hepatic injury, providing a lower incidence of adhesions between the liver and surrounding structures. avaliar a eficácia de um adesivo à base de colágeno associado a fibrinogênio e trombina, no trauma hepático experimental em ratos. foram incluídos no estudo 30 ratos Wistar, igualmente divididos aleatoriamente em três grupos: A, B e C. Todos foram submetidos à lesão traumática hepática padronizada. No grupo A a lesão foi tratada com o adesivo, no grupo B com sutura convencional com fio absorvível e no grupo C não houve tratamento da lesão. Foram analisados o tempo de hemostasia, mortalidade, ocorrência de aderências e eventuais alterações histológicas. os resultados mostraram que não houve diferença estatística em relação à mortalidade (p=0,5820). O grupo tratado com adesivo apresentou os menores tempos de hemostasia (p=0,0573 e odds ratio 13,5) e menor ocorrência de aderências (p=0,0119). Microscopicamente, as alterações histológicas dos grupos A e B foram semelhantes, com a formação de granuloma de corpo estranho separando o material do adesivo e do fio de sutura do estroma hepático. o estudo concluiu que o adesivo de colágeno associado a fibrinogênio e trombina foi eficaz no tratamento do trauma hepático experimental, proporcionado menor ocorrência de aderências entre o fígado e as estruturas vizinhas.

  20. Investigating the Interactions, Beliefs, and Practices of Teacher-Coach Teams in a STEM After-School Setting

    NASA Astrophysics Data System (ADS)

    Swanson Hoyle, Kylie Jayne

    After-school programs, such as a STEM Career Club, can promote student interest, engagement, and awareness of STEM majors and fields, as well as encourage teachers to become more knowledgeable and competent in STEM areas. In this dissertation study, two schools were selected from a larger NSF-funded project to participate in this study. Teacher- Coaches (T-Coaches) from two rural middle schools in the southeastern United States (U.S.) participated in teacher professional development (TPD) sessions and Professional Learning Community (PLC) meetings to prepare them to lead an after-school STEM Club. The Community of Practice (CoP) framework and Social Cognitive Theory are employed to investigate underlying factors that contribute to teacher interactions and preparations, and differing STEM program outcomes. Data from the Dimensions of Success (DoS) observation tool, the teacher belief interview (TBI), T-Coach participation and attendance at TPD, attendance and audio recordings from PLC meetings, and T-Coach card sorts were analyzed over approximately 6 meetings for 5 months. Findings are presented in two chapters. In Chapter Four, a comparative case study of the interactions of the teachers at two participating middle schools is analyzed. Results indicate that for each case, the club's T-Coaches interacted positively to prepare for club meetings and have a well-functioning CoP within their PLC. The first case (Northern Middle School) interacted in ways that aligned with the CoP framework (enterprise and repertoire), which led them to achieve, on average, desirable ratings on 7 of the 12 DoS dimensions. However, the other case (Southern Middle School), the T-Coaches interacted in ways that demonstrated more equal levels of enterprise, mutuality, and repertoire; this PLC had higher DoS ratings during the STEM Clubs in all dimensions (11/12 met desirable ratings). These findings suggest that high levels of all of the social learning characteristics within PLCs can support more exemplary STEM Club implementation. In Chapter Five, results from the two schools of teachers' beliefs and practices indicate that for STEM program success, the whole of the team is better than the sum of its parts. Since individuals' values on each team aligned with different DoS dimensions, it was more likely that each dimension would be represented during STEM Clubs. Findings suggest that it was necessary for two T-Coaches who valued a certain dimension to ensure a DoS dimension would be met on the DoS rating. However, it was not sufficient that T-Coaches only valued a certain dimension. The dimension was not met if the T-Coaches did not have the training and preparation to meaningfully act on their beliefs. Informed by factors from Bandura's Social Cognitive Theory, these T-Coaches carried out different behaviors at the STEM Clubs depending on their personal beliefs and values, and the environment. Five TPD participation scenarios, ranging from full to no TPD preparation, identified from the findings seemed to predict the quality of the STEM Club, based on DoS scores. The following conclusions can be drawn: 1) Professional learning community meetings aided in the development of T-Coaches' community of practice and preparation for STEM clubs; 2) A CoP with high levels of all of the social learning characteristics (enterprise, mutuality, and repertoire) led to more desirable club outcomes than a team with lower levels in any of these areas; 3) At least two people who have developed the content knowledge and relevant skills and who value club success were needed at club meetings to ensure STEM Club success; 4) Teacher-Coaches became more prepared to lead successful STEM Clubs through engaged attendance at TPD and PLC meetings; 5) Interdisciplinary teacher teams, including non-STEM teachers, can successfully lead STEM clubs if the individuals are able to learn the content/skills.

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