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Molecular mechanisms underlying the regulation of brain-derived neurotrophic factor (BDNF) translation in dendrites

Pinheiro, Vera Lúcia Margarido
Fonte: Universidade de Coimbra Publicador: Universidade de Coimbra
Tipo: Dissertação de Mestrado
ENG
Relevância na Pesquisa
35.59%
A especificidade espacial e temporal subjacente à diversidade de processos de plasticidade sináptica que ocorrem no sistema nervoso central está profundamente relacionada com a disponibilidade da proteína brain-derived neurotrophic factor (BDNF) em domínios sub-celulares distintos, especialmente na área pós-sináptica. Contudo, os mecanismos moleculares que regulam a síntese proteica de BDNF nas dendrites estão ainda por desvendar. Assim, o principal objectivo deste trabalho foi investigar alguns dos mecanismos de regulação da síntese de BDNF em diferentes regiões das dendrites. Em particular, foram estudados os mecanismos envolvidos na regulação dos níveis de BDNF em resposta à estimulação eléctrica in vitro e a um estímulo epileptogénico in vivo, e a contribuição da maquinaria de síntese proteica para essas alterações. Usando imunocitoquímica demonstrámos que o aumento dos níveis da proteína BDNF resultante da actividade neuronal está dependente da acção de alguns elementos no processo de síntese proteica. Em particular, a proteína ribossomal S6 parece ter um papel preponderante nas fases iniciais da tradução, enquanto a cinase de proteínas Aurora A, envolvida em mecanismos de tradução dependentes de 3’UTR...

The Potiguar Eddy: a subsurface anticyclone associated with the North Brazil Undercurrent at 4ºS; O vórtice Potiguar: um anticiclone subsuperficial associado à subcorrente norte do Brasil em 4ºS

Krelling, Ana Paula Morais
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 27/02/2015 EN
Relevância na Pesquisa
35.33%
In this dissertation we describe a newly discovered subsurface frontal meander of the North Brazil Undercurrent (NBUC), centered at about 4ºS, 36.5ºW, hereafter Potiguar Eddy (PE). The Potiguar Eddy is an elliptically-shaped eddy, with major and minor axes of approximately 330 and 130 km, with a subsurface signature. It extends vertically from 100 m to 400 m, with maximum velocities of 0.6 m.s-1 and recirculates about 2 Sv of waters from the NBUC. Despite the presence of the PE in subtermocline waters, the surface flow is northwestward throughout the year. The analysis of variability of mooring velocity data in the Potiguar Bight revealed two most important statistical modes of variability (EOFs); one with high amplitudes over most of the portion of the water column which corresponds to the PE, and another one, explaining a lower percentage of the variance, associated with upper-layer processes. The first EOF mode is found to be associated with baroclinic oscillations with periods of about 25-35 days. This signal is also seen in altimetric fields in the Atlantic Ocean. We characterize these signals as Rossby waves, and speculate that the trigger for their generation would be barotropic instability generated by the current shear in the Tropical Atlantic Ocean. Aditionally...

Modelo biomecânico tridimensional para análise das forças internas atuantes na coluna cervical superior e inferior durante o ciclismo

Pasini, Maicon
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
25.55%
Elevados índices de dor cervical e lombar têm sido reportados em ciclistas. Fatores como a postura adotada na bicicleta, a ativação dos músculos extensores da coluna e a ação de cargas mecânicas nas estruturas da coluna tem sido apontados como possíveis causas da dor. Embora relatados e aparentemente aceitos, poucos estudos objetivaram investigar estes fatores. Em adição, a dor crônica não específica é frequentemente diagnosticada em ciclistas, pois poucas evidências de anormalidade são observadas quando realizados exames radiológicos clínicos. O emprego de métodos biomecânicos de investigação, como a estimativa da magnitude da força muscular dos extensores da coluna e da força articular em diferentes níveis da coluna poderia contribuir para avaliação do risco de lesão e dor em decorrência do ciclismo, além de auxiliar na criação de estratégias de prevenção e programas de reabilitação. Assim, este estudo teve como objetivo quantificar e comparar as forças internas atuantes na coluna cervical durante o ciclismo em diferentes posturas, por meio do desenvolvimento e aplicação de um modelo biomecânico tridimensional in vivo. O modelo biomecânico proposto foi composto por dois segmentos rígidos (coluna cervical superior e inferior) conectados. O segmento coluna cervical superior compreende a cabeça...

Sedimentological study of the western zone of the Lady Annie phosphate deposit, Queensland, Australia

Elgueta, Sara
Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Tipo: Thesis (Masters); Master by research (Masters)
EN_AU
Relevância na Pesquisa
65.43%
A detailed sedimentological study of part of a major phosphate deposit within the Middle Cambrian Georgina Basin phosphogenic province was undertaken in order to establish a depositional model, to determine the sedimentary parameters controlling phosphorite deposition and to identify the factors influencing phosphate grade. The study was concentrated on the Western Zone of the Lady Annie deposit which, together with the Lady Jane deposit, occurs in an elongate north-south outlier surrounded by Precambrian basement rocks on the eastern margin of the Georgina Basin. Field investigations were directed principally towards understanding the spatial relationships between phosphorites and associated non-phosphatic sediments within the same overall palaeoenvironment. Field mapping and measurement of stratigraphic sequences and palaeocurrent data resulted in the recognition of eight major sedimentary lithofacies: a basal conglomerate-sandstone facies, an undifferentiated carbonated facies, a laminate facies, an oncolite facies, a skeletal facies, a phosphorite facies, a chert-terrigenous facies and a siltstone facies. The detailed description of twenty-three vertical sections from six trenches which expose part of the phosphorite facies shows that the phosphorites consist of a relatively monotonous succession of well bedded to laminnted grainstone and packstone phosphorite interbedded with chert and minor lenticular beds of fine siliciclastic sediments. Wackestone and mudstone phosphorites form minor components in the trenches and characteristically occur in the upper portion of the phosphorite sequence. Thin section petrography of about 74 selected samples from the trenches shows that the grainstone-packstone phosphorite varies in grain size between very coarse and very fine sand. Grains resemble carbonate clastic grains and consist of varying proportions of rounded and relatively well sorted fossil fragments (mainly fragments of calcisponges and echinoderms)...

The geochronology and radiogenic isotope systematics of the Olympic Dam copper-uranium-gold-silver deposit, South Australia

Johnson, James Patrick
Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Tipo: Thesis (PhD)
EN_AU
Relevância na Pesquisa
45.33%
The Olympic Dam Cu-U-Au-Ag deposit is a syngenetic orebody hosted by the Olympic Dam Breccia Complex, a high level, hematite-rich hydrothermal breccia system. The breccia complex occurs entirely within, and clearly post-dates, the Roxby Downs Granite. _Cu-Fe sulphide distribution within the deposit is zoned from pyrite-rich assemblages at depth, upwards to chalcopyrite-rich ores, ultimately to bornite-chalcocite ores. Mlnor proportions of paragenetically early magnetite are widely distributed. Felsic and mafic/ultramafic dykes are broadly coeval with ore deposition. The Roxby Downs Granite has an age of 1588 ± 4 Ma. Prior to this study the age of the breccia complex was unclear. SHRIMP U-Pb isotopic data for zircons from three igneous rock units constrain the minimum age for the bulk of the mineralisation. Twb autobrecciated felsic dykes that intrude hematite-rich sedimetitary rocks and·hydrothermal breccias have ages of 1592.± 8 Ma and 1584 ±- 20 Ma respectively. An ashfall tuff horizon from within a diatrerne that cross-cuts hematite-quartz breccias contains zircons with an age of 1597 ± 8 Ma. These three minimum age constraints are within error of the age of the host granite, meaning that the breccia complex has an age of -1590 Ma. This age determination allows confident correlation of ore deposition with a major regional magmatic episode...

El derecho a la libertad religiosa y el uso del velo islámico. Marco constitucional, normativo y jurisprudencial

García Gestoso, Noemí
Fonte: Universidade da Coruña Publicador: Universidade da Coruña
Tipo: Artigo de Revista Científica
SPA
Relevância na Pesquisa
75.38%
[Resumen] El presente trabajo de investigación aborda, en primera instancia, el estudio del derecho a la libertad religiosa y el uso del velo islámico en el marco constitucional, normativo y jurisprudencial del Estado español. En segundo lugar, se observan las peculiaridades de la regulación de esta materia en el ámbito del Derecho comparado: desde los Estados que han mostrados más reticencias al respecto, como Francia y Turquía, pasando por aquellos que como Reino Unido han promovido activamente el pluralismo religioso, o aquellos otros que, con menor o mayor intensidad, han apostado por limitar el uso del velo en los espacios públicos, como Holanda, Dinamarca y Bélgica. Finalmente, el artículo se cierra con unas reflexiones sobre el derecho a la educación, que se configura como un instrumento básico en orden a la consecución de la integración e igualdad social.; [Abstract] The present work of investigation tackles, in first instance, the study of the right to religious freedom and the use of the Islamic veil in the constitutional frame, normative and jurisprudential of the Spanish State. Second, it observes the peculiarities of the regulation of this matter in the field of the Comparative Law: from the States that have showed more reticence in this regard...

Deduction of Semi-Optimal Mollifier for Obtaining Lower Bound for N0(T) for Riemann's Zeta-Function

Levinson, Norman
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /01/1975 EN
Relevância na Pesquisa
35.33%
A mollifier played a key role in showing N0(T) > 1/3N(T) for large T in ref. 1 [Levinson, N. (1974) Advan. Math. 13, 383-436]. A basic problem in ref. 1 was that of obtaining an upper bound for a sum of two terms, one larger than the other. Here a deductive procedure is given for finding a mollifier that actually minimizes the larger term. An Euler-Lagrange equation is obtained. (Optimization of the sum of both the major and minor terms appears to be formidable.) The actual improvement effected by the optimized mollifier over the ad hoc mollifier of ref. 1 is unfortunately only 1.4%. To obtain a usable mollifier it is necessary to blur the optimization procedure by smoothing at several stages of the deduction. The procedure is of more interest than the particular application because of the small improvement in this case.

The treatment of gastroesophageal reflux disease with laparoscopic Nissen fundoplication: prospective evaluation of 100 patients with "typical" symptoms.

Peters, J H; DeMeester, T R; Crookes, P; Oberg, S; de Vos Shoop, M; Hagen, J A; Bremner, C G
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /07/1998 EN
Relevância na Pesquisa
35.33%
OBJECTIVE: To evaluate prospectively the outcome of laparoscopic fundoplication in a large cohort of patients with typical symptoms of gastroesophageal reflux. SUMMARY BACKGROUND DATA: The development of laparoscopic fundoplication over the past several years has resulted in renewed interest in the surgical treatment of gastroesophageal reflux disease (GERD). METHODS: One hundred patients with typical symptoms of GERD were studied. The study was limited to patients with positive 24-hour pH studies and "typical" symptoms of GERD. Laparoscopic fundoplication was performed when clinical assessment suggested adequate esophageal motility and length. Outcome measures included assessment of the relief of the primary symptom responsible for surgery; the patient's and the physician's evaluation of outcome; quality of life evaluation; repeated upper endoscopy in 30 patients with presurgical esophagitis; and postsurgical physiologic studies in 28 unselected patients, consisting of 24-hour esophageal pH and lower esophageal sphincter manometry. RESULTS: Relief of the primary symptom responsible for surgery was achieved in 96% of patients at a mean follow-up of 21 months. Seventy-one patients were asymptomatic, 24 had minor gastrointestinal symptoms not requiring medical therapy...

Microfósiles marinos del eoceno inferior, Isla Grande de Tierra del Fuego, Argentina: bioestratigrafía, paleoambiente y paleobiogeografía; Marine microfossils from the lower eocene, Isla Grande de Tierra del Fuego, Argentina: biostratigraphy, paleoenvironment and paleobiogeography

Jannou, Gabriel Eugenio
Fonte: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires Publicador: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires
Tipo: info:eu-repo/semantics/doctoralThesis; tesis doctoral; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em //2009 SPA
Relevância na Pesquisa
45.43%
Se analizan los microfósiles de la Formación Punta Torcida (Eoceno inferior marino) de la Isla Grande de Tierra del Fuego, cuenca Austral. El estudio reviste particular interés ya que da a conocer las características microfaunísticas, las condiciones paleobiogeográficas, paleoambientales y paleoclimáticas del extremo sur de América del Sur, para uno de los momentos más singulares de la historia cenozoica. Se trata del primer análisis micropaleontológico integral, con ilustración de foraminíferos, ostrácodos y radiolarios para el Eoceno inferior del sur de América del Sur. Según sus foraminíferos planctónicos, la Formación se sitúa dentro de la Zona de Globigerina wilcoxensis de Nueva Zelanda, o el equivalente tropical de las Zonas P7 a P8, o las Zonas AP6b a AP7 de la Antártida, o la Zona AE3 a parte baja de la Zona AE4 de la zonación circumantártica, que se calibrarían entre 52,3 y 49,3 Ma. Los radiolarios, que provienen del miembro superior de la Formación en la localidad tipo de cabo Campo del Medio y en las cercanías de cabo Irigoyen, indican una edad equivalente a las zonas de radiolarios RP9 a parte baja de RP10 del Pacífico Sur, o el equivalente tropical de las Zonas de Buryella clinata a Phormocyrthis striata striata...

General solution of an exact correlation function factorization in conformal field theory

Simmons, Jacob J. H.; Kleban, Peter
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
35.33%
We discuss a correlation function factorization, which relates a three-point function to the square root of three two-point functions. This factorization is known to hold for certain scaling operators at the two-dimensional percolation point and in a few other cases. The correlation functions are evaluated in the upper half-plane (or any conformally equivalent region) with operators at two arbitrary points on the real axis, and a third arbitrary point on either the real axis or in the interior. This type of result is of interest because it is both exact and universal, relates higher-order correlation functions to lower-order ones, and has a simple interpretation in terms of cluster or loop probabilities in several statistical models. This motivated us to use the techniques of conformal field theory to determine the general conditions for its validity. Here, we discover a correlation function which factorizes in this way for any central charge c, generalizing previous results. In particular, the factorization holds for either FK (Fortuin-Kasteleyn) or spin clusters in the Q-state Potts models; it also applies to either the dense or dilute phases of the O(n) loop models. Further, only one other non-trivial set of highest-weight operators (in an irreducible Verma module) factorizes in this way. In this case the operators have negative dimension (for c < 1) and do not seem to have a physical realization.; Comment: 7 pages...

Inverse Littlewood-Offord problems and The Singularity of Random Symmetric Matrices

Nguyen, Hoi H.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
35.34%
Let $M_n$ denote a random symmetric $n$ by $n$ matrix, whose upper diagonal entries are iid Bernoulli random variables (which take value -1 and 1 with probability 1/2). Improving the earlier result by Costello, Tao and Vu, we show that $M_n$ is non-singular with probability $1-O(n^{-C})$ for any positive constant $C$. The proof uses an inverse Littlewood-Offord result for quadratic forms, which is of interest of its own.; Comment: Some minor corrections in Section 10 of v1

The sup-norm problem for the Siegel modular space of rank two

Blomer, Valentin; Pohl, Anke
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
35.34%
Let F be a square integrable Maass form on the Siegel upper half space of rank 2 for the Siegel modular group Sp(4, Z) with Laplace eigenvalue lambda. If, in addition, F is a joint eigenfunction of the Hecke algebra, we show a power-saving sup-norm bound in terms of lambda (relative to the generic bound) for F restricted to a compact set. As an auxiliary result of independent interest we prove new uniform bounds for spherical functions on semisimple Lie groups.; Comment: Version 2 contains new bounds for spherical functions on semisimple Lie groups and some additional minor changes

Chances for SUSY-GUT in the LHC Epoch

Berezhiani, Zurab; Chianese, Marco; Miele, Gennaro; Morisi, Stefano
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
45.34%
The magic couple of SUSY and GUT still appears the most elegant and predictive physics concept beyond the Standard Model. Since up to now LHC found no evidence for supersymmetric particles it becomes of particular relevance to determine an upper bound of the energy scale they have to show up. In particular, we have analyzed a generic SUSY-GUT model assuming one step unification like in SU(5), and adopting naturalness principles, we have obtained general bounds on the mass spectrum of SUSY particles. We claim that if a SUSY gauge coupling unification takes place, the lightest gluino or Higgsino cannot have a mass larger than about 20 TeV. Such a limit is of interest for planning new accelerator machines.; Comment: 23 pages, 5 figures. Version published in JHEP, minor corrections added and images improved

Radio Flares and the Magnetic Field Structure in GRB Outflows

Granot, Jonathan; Taylor, Gregory B.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
35.38%
The magnetic field structure in GRB outflows is of great interest as it can provide valuable clues that can help pin down the mechanism responsible for the acceleration and collimation of GRB jets. The most promising way of probing it is through polarization measurements of the synchrotron emission from the GRB ejecta, which includes the gamma-ray emission and the reverse shock emission. Measuring polarization in gamma-rays with current instruments is extremely difficult: so far there is only one claim of detection (in GRB 021206) which despite the favorable conditions remains very controversial. The emission from the reverse shock that propagates into the ejecta as it is decelerated by the ambient medium peaks in the optical after tens of seconds (the `optical flash') and dominates the optical emission up to about ten minutes after the GRB. Unfortunately, no polarization measurements of this optical emission have been made to date. However, after the reverse shock finishes crossing the shell of GRB ejecta, the shocked ejecta cools adiabatically and radiates at lower and lower frequencies, peaking in the radio after $\sim 1$ day (the `radio flare'). We use VLA data of radio flares from GRBs to constrain the polarization of this emission. We find only upper limits for both linear and circular polarization. Our best limits are for GRB 991216...

Generalizing and Derandomizing Gurvits's Approximation Algorithm for the Permanent

Aaronson, Scott; Hance, Travis
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
35.33%
Around 2002, Leonid Gurvits gave a striking randomized algorithm to approximate the permanent of an n*n matrix A. The algorithm runs in O(n^2/eps^2) time, and approximates Per(A) to within eps*||A||^n additive error. A major advantage of Gurvits's algorithm is that it works for arbitrary matrices, not just for nonnegative matrices. This makes it highly relevant to quantum optics, where the permanents of bounded-norm complex matrices play a central role. Indeed, the existence of Gurvits's algorithm is why, in their recent work on the hardness of quantum optics, Aaronson and Arkhipov (AA) had to talk about sampling problems rather than estimation problems. In this paper, we improve Gurvits's algorithm in two ways. First, using an idea from quantum optics, we generalize the algorithm so that it yields a better approximation when the matrix A has either repeated rows or repeated columns. Translating back to quantum optics, this lets us classically estimate the probability of any outcome of an AA-type experiment---even an outcome involving multiple photons "bunched" in the same mode---at least as well as that probability can be estimated by the experiment itself. (This does not, of course, let us solve the AA sampling problem.) It also yields a general upper bound on the probabilities of "bunched" outcomes...

Alexander and Thurston norms of fibered 3-manifolds

Dunfield, Nathan M.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
35.33%
For a 3-manifold M, McMullen derived from the Alexander polynomial of M a norm on H^1(M, R) called the Alexander norm. He showed that the Thurston norm on H^1(M, R), which measures the complexity of a dual surface, is an upper bound for the Alexander norm. He asked if these two norms were equal on all of H^1(M,R) when M fibers over the circle. Here, I give examples which show that the answer to this question is emphatically no. This question is related to the faithfulness of the Gassner representations of the braid groups. The key tool used to understand this question is the Bieri-Neumann-Strebel invariant from combinatorial group theory. Theorem 1.7, which is of independant interest, connects the Alexander polynomial with a certain Bieri-Neumann-Strebel invariant.; Comment: 14 pages, 7 figures. To appear in PJM. v2: Minor corrections over v1

Near-IR Integral Field Spectroscopy study of the Star Formation and AGN of the LIRG NGC 5135

Bedregal, A. G.; Colina, L.; Alonso-Herrero, A.; Arribas, S.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
45.33%
We present a study of the central 2.3 kpc of NGC 5135, a nearby Luminous Infrared Galaxy (LIRG) with an AGN and circumnuclear starburst. Our main results are based on intermediate spectral resolution (~ 3000-4000) near infrared data taken with the SINFONI integral field spectrograph at the ESO VLT. The ionization of the different phases of the interstellar gas and the complex structures of the star formation have been mapped. Individual regions of interest have been identified and studied in detail. For the first time in this galaxy, we have detected the presence of a high excitation ionization cone centered on the AGN by using the [SiVI] (1.96 micron) line. So far, this structure is the largest reported in the literature for this coronal line, extending (in projection) as far as ~ 600 pc from the galaxy nucleus. In a complex spatial distribution, a variety of mechanisms are driving the gas ionization, including SNe remnant shocks, young stars and AGN photoionization. The excitation of the molecular gas, however, is mainly produced by X-rays and SNe remnant shocks. UV-mechanisms like fluorescence represent a marginal overall contribution to this process, contrary to the expectations we might have for a galaxy with a recent and strong star formation. Our SNe rate estimations from [FeII] (1.64 micron) are in excellent agreement with 6 cm radio emission predictions. Typical SNe rates between 0.01-0.04 yr^-1 were found for individual ~ 200 pc-scale regions...

New Fe I level energies and line identifications from stellar spectra

Peterson, Ruth C.; Kurucz, Robert L.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
35.41%
The spectrum of the Fe I atom is critical to many areas of astrophysics and beyond. Measurements of the energies of its high-lying levels remain woefully incomplete, however, despite extensive analysis of ultraviolet laboratory iron absorption spectra, optical laboratory iron emission spectra, and the solar infrared spectrum. In this work we use as sources the high-resolution archival absorption-line ultraviolet and optical spectra of stars, whose warm temperatures favor moderate Fe I excitation. We derive the energy for a particular upper level in Kurucz's semiempirical calculations by adopting a trial value that yields the same wavelength for a given line predicted to be about as strong as that of a strong unidentified spectral line observed in the stellar spectra, then checking the new wavelengths of other strong predicted transitions that share the same upper level for coincidence with other strong observed unidentified lines. To date this analysis has provided the upper energies of 66 Fe I levels. Many new level energies are higher than those accessible to laboratory experiments; several exceed the Fe I ionization energy. These levels provide new identifications for over two thousand potentially detectable lines. Almost all of the new levels of odd parity include UV lines that were detected but unclassified in laboratory Fe I absorption spectra...

Predicting the redshift 2 Halpha luminosity function using [OIII] emission line galaxies

Mehta, Vihang; Scarlata, Claudia; Colbert, James W.; Dai, Sophia; Dressler, Alan; Henry, Alaina; Malkan, Matt; Rafelski, Marc; Siana, Brian; Teplitz, Harry; Bagley, Micaela; Beck, Melanie; Ross, Nathaniel R.; Rutkowski, Michael; Wang, Yun
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
55.33%
Upcoming space-based surveys such as Euclid and WFIRST-AFTA plan to measure Baryonic Acoustic Oscillations (BAOs) in order to study dark energy. These surveys will use IR slitless grism spectroscopy to measure redshifts of a large number of galaxies over a significant redshift range. In this paper, we use the WFC3 Infrared Spectroscopic Parallel Survey (WISP) to estimate the expected number of Halpha (Ha) emitters observable by these future surveys. WISP is an ongoing HST slitless spectroscopic survey, covering the 0.8-1.65micron wavelength range and allowing the detection of Ha emitters up to z~1.5 and [OIII] emitters to z~2.3. We derive the Ha-[OIII] bivariate line luminosity function for WISP galaxies at z~1 using a maximum likelihood estimator that properly accounts for uncertainties in line luminosity measurement, and demonstrate how it can be used to derive the Ha luminosity function from exclusively fitting [OIII] data. Using the z~2 [OIII] line luminosity function, and assuming that the relation between Ha and [OIII] luminosity does not change significantly over the redshift range, we predict the Ha number counts at z~2 - the upper end of the redshift range of interest for the future surveys. For the redshift range 0.7

Avian Influenza Infection Dynamics in Minor Avian Species

Bertran Dols, Kateri
Fonte: [Barcelona] : Universitat Autònoma de Barcelona, Publicador: [Barcelona] : Universitat Autònoma de Barcelona,
Tipo: Tesis i dissertacions electròniques; info:eu-repo/semantics/doctoralThesis Formato: application/pdf
Publicado em //2013 ENG; ENG
Relevância na Pesquisa
35.38%
Amb la fi de comprendre la dinàmica de la infecció pel VIA en aquestes tres espècies aviàries no convencionals, així com la funció epidemiològica que exercirien en un brot interespècie d'IA per tal de definir millors estratègies de vigilància, es van realitzar tres infeccions experimentals, les quals s'han descrit en aquesta tesi. La patogènia de la infecció tant pel VI13P com pel VIABP es va determinar per a la perdiu roja (Estudi I), la guatlla europea (Estudi II) i el falcó híbrid sacre‐grifó (Estudi III), posant especial èmfasi en la descripció de la malaltia clínica, les lesions macroscòpiques i microscòpiques, i la presència de l'antigen víric als teixits. A més, en aquest treball s'ha descrit el patró d'excreció vírica de cada espècie aviària i cada VIA, i s'ha avaluat la probabilitat d'una eficaç transmissió vírica entre animals. L'Estudi II també representa un estudi comparatiu de la dinàmica d'infecció en dos subtipus diferents de VIABP (H7 i H5). En el cas dels Estudis I i II, es va prestar especial atenció en les plomes com a possible origen de propagació del VIA. A més, a l'Estudi II es va investigar l'aigua com a possible ruta de transmissió. Finalment, a l'Estudi III es va reproduir amb eficiència la infecció natural pel VIA en falcons (és a dir...