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Terbium(III) and dysprosium(III) 8-connected 3D networks containing 2,5-thiophenedicarboxylate anion: Crystal structures and photoluminescence studies

Marques, Lippy F.; dos Santos, Moliria V.; Ribeiro, Sidney J. L.; Castellano, Eduardo Ernesto; Machado, Flavia C.
Fonte: PERGAMON-ELSEVIER SCIENCE LTD; OXFORD Publicador: PERGAMON-ELSEVIER SCIENCE LTD; OXFORD
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
45.53%
Two novel coordination polymers with the formula {[Ln(2)(2,5-tdc)(3)(dmso)(2)].H2O}(n) (Ln = Tb(III) for (1) and Dy(III) for (2)), (2,5-tdc(2-) = 2,5-thiophenedicarboxylate and dmso = dimethylsulfoxide) have been synthesized by the diffusion method and characterized by thermal analysis, vibrational spectroscopy and single crystal X-ray diffraction analysis. Structure analysis reveals that 2,5-tdc(2-) play a versatile role toward different lanthanide ions to form three-dimensional metal-organic frameworks (MOFs) in which the lanthanides ions are heptacoordinated. Photophysical properties were studied using excitation and emission spectra, where the photoluminescence data show the high emission intensity of the characteristic transitions D-5(4 ->) F-7(J) (J= 6, 5, 4 and 3) for (1) and (F9/2 -> HJ)-F-4-H-6 (J = 15/2, 13/2 and 11/2) for (2), indicating that 2,5-tdc(2-) is a good sensitizer. (C) 2012 Elsevier Ltd. All rights reserved.; CNPq; CNPq; CAPES; CAPES; FAPEMIG; FAP-EMIG [CEX-APQ 01565-09]

Terbium(III) and dysprosium(III) 8-connected 3D networks containing 2,5-thiophenedicarboxylate anion: Crystal structures and photoluminescence studies

Marques, Lippy F.; dos Santos, Moliria V.; Ribeiro, Sidney J. L.; Castellano, Eduardo Ernesto; Machado, Flavia C.
Fonte: Pergamon-Elsevier B.V. Ltd Publicador: Pergamon-Elsevier B.V. Ltd
Tipo: Artigo de Revista Científica Formato: 149-156
ENG
Relevância na Pesquisa
45.53%
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Two novel coordination polymers with the formula {[Ln(2)(2,5-tdc)(3)(dmso)(2)].H2O}(n) (Ln = Tb(III) for (1) and Dy(III) for (2)), (2,5-tdc(2-) = 2,5-thiophenedicarboxylate and dmso = dimethylsulfoxide) have been synthesized by the diffusion method and characterized by thermal analysis, vibrational spectroscopy and single crystal X-ray diffraction analysis. Structure analysis reveals that 2,5-tdc(2-) play a versatile role toward different lanthanide ions to form three-dimensional metal-organic frameworks (MOFs) in which the lanthanides ions are heptacoordinated. Photophysical properties were studied using excitation and emission spectra, where the photoluminescence data show the high emission intensity of the characteristic transitions D-5(4 ->) F-7(J) (J= 6, 5, 4 and 3) for (1) and (F9/2 -> HJ)-F-4-H-6 (J = 15/2, 13/2 and 11/2) for (2), indicating that 2,5-tdc(2-) is a good sensitizer. (C) 2012 Elsevier Ltd. All rights reserved.

Exatidão de classificações automáticas de uma imagem LANDSAT 5 TM para a região cafeeira de Machado, MG.

SANTOS, W. J. R.; VIEIRA, T. G. C.; BERNARDES, T.; ALVES, H. M. R.; SILVEIRA, S. P. S.
Fonte: In: SIMPÓSIO DE PESQUISA DOS CAFÉS DO BRASIL, 5., 2007, Águas de Lindóia, SP. Anais... Brasília, DF: Embrapa Café, 2007. Publicador: In: SIMPÓSIO DE PESQUISA DOS CAFÉS DO BRASIL, 5., 2007, Águas de Lindóia, SP. Anais... Brasília, DF: Embrapa Café, 2007.
Tipo: Artigo em anais de congresso (ALICE)
PT_BR
Relevância na Pesquisa
55.43%
O presente trabalho avalia a acurácia de dois classificadores automáticos disponíveis no Sistema de Informação Geográfica SPRING para o mapeamento de uso e ocupação da terra da região cafeeira de Machado, MG. Foram utilizados os classificadores: Battacharya, ?por região?; e o Máxima Verossimilhança (Maxver), ?pixel a pixel? para a imagem Landsat 5 TM e como referência foi utilizada a imagem do satélite Spot 4 classificada visualmente e validada em campo. Ambos algoritmos demonstraram baixo rendimento para a região. Posteriormente às classificações, foram criadas matrizes de erro, comparando as classificações automáticas com a visual. O desempenho das classificações foi avaliado pelos índices de exatidão Global, Kappa e Tau. O baixo desempenho das classificações pode ser explicado pela região cafeeira de Machado possuir um relevo muito movimentado, proporcionando regiões sombreadas e lavouras cafeeiras contíguas a fragmentos de vegetação nativa, os quais apresentam resposta espectral semelhante.; 2007

Taxa de concepção de cabras inseminadas com sêmen caprino resfriado a 5°C, por 12 ou 24 horas, em meio diluidor à base de gema de ovo.

SIQUEIRA, A. P.; SILVA FILHO, J. M.; FONSECA, J. F. da; BRUSCHI, J. H.; PALHARES, M. S.; BORGES, A. M.; BRUSCHI, M. C. M.; PEIXOTO, M. P.; ROSSI, R.
Fonte: Arquivo Brasileiro de Medicina Veterinária e Zootecnia, Belo Horizonte, v. 61, n. 1, p. 66-71, 2009. Publicador: Arquivo Brasileiro de Medicina Veterinária e Zootecnia, Belo Horizonte, v. 61, n. 1, p. 66-71, 2009.
Tipo: Artigo em periódico indexado (ALICE)
PT_BR
Relevância na Pesquisa
45.52%
Avaliou-se a capacidade fecundante do sêmen caprino resfriado a 5°C, por 12 (TI) ou 24 horas (TII), em container especial. Para tanto, utilizaram-se 62 fêmeas e dois reprodutores (B1 e B2) da raça Toggenburg, distribuídos em um esquema fatorial 2x2 (dois reprodutores e dois períodos de estocagem do sêmen). Após a coleta, o sêmen foi diluído em Tris-frutose-gema de ovo a 2,5%, envasado em palhetas de 0,25mL, com 150x106 espermatozoides móveis e resfriado a 5oC. As fêmeas receberam duas doses de 22,5µg de PGF2a, em intervalos de 10 dias para a sincronização do estro. A partir da primeira aplicação de PGF2a, as fêmeas foram monitoradas para ocorrência de estro, três vezes ao dia. Realizou-se uma única inseminação, pela técnica de fixação da cérvice, 12 horas após o início do estro. A motilidade e o vigor, após 12 ou 24 horas de resfriamento, foram de 66,14±0,11% e 62,50±0,05%, e 3,46±0,61 e 3,27±0,50, respectivamente. Não houve influência (P>0,05) do reprodutor, nem do período de armazenamento do sêmen sobre a taxa de concepção das cabras, que foi de 49,1%. Conception rate of goats inseminated with semen cooled in egg yolk diluent at 5 degrees C, for 12 or 24 hours. Abstract: The fertilizing capacity of goat semen cooled in egg yolk diluent at 5 degrees C...

A case study of the mesospheric 6.5-day wave observed by radar systems

Jiang, G.Y.; Xu, J.; Xiong, J.G.; Ma, R.; Ning, B.Q.; Murayama, Y.; Thorsen, D.; Gurubaran, S.; Vincent, R.; Reid, I.; Franke, S.
Fonte: Amer Geophysical Union Publicador: Amer Geophysical Union
Tipo: Artigo de Revista Científica
Publicado em //2008 EN
Relevância na Pesquisa
45.51%
In this paper, analysis of wind data detected by six ground-based radar systems located in equatorial and midlatitude belts shows that a strong mesospheric 6.5-day wave event occurred during April–May 2003. We compared the global distribution of the observed 6.5-day wave event with the theoretical wave structure (Rossby normal mode (s, n) = (1, −2)). Additionally, we investigated several important wave characteristics to understand the mesospheric 6.5-day wave event, i.e., wave period, vertical structure, relationship with background wind, propagating direction, and the zonal wave number. Our results are summarized into three points: (1) the latitudinal structure of the mesospheric 6.5-day wave during April–May 2003 is basically in agreement with the theoretical Rossby mode (s, n) = (1, −2), although the wave amplitude of zonal wind peaked at the subequatorial latitude of Northern Hemisphere but not at the theoretical place, equatorial region; (2) the main wave periods and the altitude distribution of large amplitude of this wave event varied with latitude; (3) the downward propagating wave phases indicated that this wave event originated in the lower atmosphere and propagated upward to the upper region.; G. Jiang, Jiyao Xu...

Effects of Streptococcus thermophilus TH-4 on intestinal mucositis induced by the chemotherapeutic agent 5-Fluorouracil (5-FU)

Whitford, E.; Cummins, A.; Butler, R.; Prisciandaro, L.; Fauser, J.; Yazbek, R.; Lawrence, A.; Cheah, K.; Wright, T.; Lymn, K.; Howarth, G.
Fonte: Landes Bioscience Publicador: Landes Bioscience
Tipo: Artigo de Revista Científica
Publicado em //2009 EN
Relevância na Pesquisa
45.52%
Beneficial bacteria (probiotics) and probiotic-derived factors have the potential to ameliorate disorders of the intestine. The aim of this study was to compare live Streptococcus thermophilus TH-4 (TH-4), dead TH-4 and TH-4 supernatant in rats treated with 5-Fluorouracil. Rats were randomly allocated to five treatment groups (n=8-10): Saline+Water; 5-FU+Skim Milk; 5-FU+Live TH-4; 5-FU+Supernatant TH-4; and 5-FU+Dead TH-4. 5-FU (150mg.kg(-1)) was administered by a single intraperitoneal injection on day 0; animals were killed on day 4. Treatments were administered daily from days -2 to 3 via oro-gastric gavage. Metabolic parameters were measured daily. Blood was obtained by cardiac puncture, and intestinal tissues removed for quantitative and qualitative histological assessment, including: villous height and area; crypt depth and area, mitotic count and crypt fission; biochemical determination of sucrase and myeloperoxidase (MPO) activity; and disease severity scoring. One-way ANOVA statistical analyses were conducted for the majority of outcome measures. Live TH-4 significantly reduced disease severity score by 13% (p< 0.05), and partially normalised mitotic counts compared with 5-FU+Skim milk controls. Live and supernatant TH-4 reduced crypt fission by 69% and 48% (p< 0.05)...

Simultaneous antagonism of interleukin-5, granulocyte-macrophage colony-stimulting factor, and interleukin-3 stimulation of human eosinophils by targetting the common cytokine binding site of their receptors

Sun, Q.; Jones, K.; McClure, B.; Cambareri, B.; Zacharakis, B.; Iversen, P.; Stomski, F.; Woodcock, J.; Bagley, C.; D'Andrea, R.; Lopez, A.
Fonte: AMER SOC HEMATOLOGY Publicador: AMER SOC HEMATOLOGY
Tipo: Artigo de Revista Científica
Publicado em //1999 EN
Relevância na Pesquisa
45.52%
Human interleukin-5 (IL-5), granulocyte-macrophage colony-stimulating factor (GM-CSF), and IL-3 are eosinophilopoietic cytokines implicated in allergy in general and in the inflammation of the airways specifically as seen in asthma. All 3 cytokines function through cell surface receptors that comprise a ligand-specific alpha chain and a shared subunit (beta(c)). Although binding of IL-5, GM-CSF, and IL-3 to their respective receptor alpha chains is the first step in receptor activation, it is the recruitment of beta(c) that allows high-affinity binding and signal transduction to proceed. Thus, beta(c) is a valid yet untested target for antiasthma drugs with the added advantage of potentially allowing antagonism of all 3 eosinophil-acting cytokines with a single compound. We show here the first development of such an agent in the form of a monoclonal antibody (MoAb), BION-1, raised against the isolated membrane proximal domain of beta(c). BION-1 blocked eosinophil production, survival, and activation stimulated by IL-5 as well as by GM-CSF and IL-3. Studies of the mechanism of this antagonism showed that BION-1 prevented the high-affinity binding of (125)I-IL-5, (125)I-GM-CSF, and (125)I-IL-3 to purified human eosinophils and that it bound to the major cytokine binding site of beta(c). Interestingly...

PHYSICAL CHARACTERISTICS OF G331.5-0.1: THE LUMINOUS CENTRAL REGION OF A GIANT MOLECULAR CLOUD

Walmsley, C. Malcolm; Nyman, Lars Ake; Garay, Guido; Bronfman Aguiló, Leonardo Jaime; Evans II, Neal J.; Merelo, Manuel
Fonte: The American Astronomical Society Publicador: The American Astronomical Society
Tipo: Artículo de revista
EN
Relevância na Pesquisa
45.55%
Artículo de publicación ISI; We report molecular line and dust continuum observations toward the high-mass star-forming region G331.5-0.1, one of the most luminous regions of massive star formation in the Milky Way, located at the tangent region of the Norma spiral arm, at a distance of 7.5 kpc. Molecular emission was mapped toward the G331.5-0.1 GMC in the CO(J = 1 → 0) and C18O(J = 1 → 0) lines with NANTEN, while its central region was mapped in CS(J = 2 → 1 and J = 5 → 4) with SEST, and in CS(J = 7 → 6) and 13CO(J = 3 → 2) with ASTE. Continuum emission mapped at 1.2 mm with SIMBA and at 0.87 mm with LABOCA reveal the presence of six compact and luminous dust clumps, making this source one of the most densely populated central regions of a GMC in the Galaxy. The dust clumps are associated with molecular gas and they have the following average properties: size of 1.6 pc, mass of 3.2 × 103M , molecular hydrogen density of 3.7 × 104 cm−3, dust temperature of 32 K, and integrated luminosity of 5.7 × 105 L , consistent with values found toward other massive star-forming dust clumps. The CS and 13CO spectra show the presence of two velocity components: a high-velocity component at ∼−89 km s−1, seen toward four of the clumps...

HCN J=5-4 Emission in APM08279+5255 at z=3.91

Wagg, J.; Wilner, D. J.; Neri, R.; Downes, D.; Wiklind, T.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 18/10/2005
Relevância na Pesquisa
55.53%
We detect HCN J=5-4 emission from the ultraluminous quasar APM08279+5255 at z=3.911 using the IRAM Plateau de Bure interferometer. This object is strongly gravitationally lensed, yet still thought to be one of the most intrinsically luminous objects in the Universe. The new data imply a line luminosity L'_HCN(J=5-4) = 4.0+/-0.5 x 10^(10) K km/s pc^2. The ~440 km/s full width half maximum of the HCN J=5-4 line matches that of the previously observed high-J CO lines in this object and suggests that the emission from both species emerges from the same region: a warm, dense circumnuclear disk. Simple radiative transfer models suggest an enhanced abundance of HCN relative to CO in the nuclear region of APM08279+5255, perhaps due to increased ionization, or possibly the selective depletion of oxygen. The ratio of far-infrared luminosity to HCN luminosity is at the high end of the range found for nearby star forming galaxies, but comparable to that observed in the few high redshift objects detected in the HCN J=1-0 line. This is the first clear detection of high-J HCN emission redshifted into the 3-millimeter atmospheric window.; Comment: Accepted for publication in ApJL

Mid-J CO observations of Perseus B1-East 5: evidence for turbulent dissipation via low-velocity shocks

Pon, Andy; Johnstone, Doug; Kaufman, Michael J.; Caselli, Paola; Plume, René
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
45.51%
Giant molecular clouds contain supersonic turbulence and magnetohydrodynamic simulations predict that this turbulence should decay rapidly. Such turbulent dissipation has the potential to create a warm (T ~100 K) gas component within a molecular cloud. We present observations of the CO J = 5-4 and 6-5 transitions, taken with the Herschel Space Observatory, towards the Perseus B1-East 5 region. We combine these new observations with archival measurements of lower rotational transitions and fit photodissociation region models to the data. We show that Perseus B1-E5 has an anomalously large CO J = 6-5 integrated intensity, consistent with a warm gas component existing within the region. This excess emission is consistent with predictions for shock heating due to the dissipation of turbulence in low velocity shocks with the shocks having a volume filling factor of 0.15 per cent. We find that B1-E has a turbulent energy dissipation rate of 3.5 x 10$^{32}$ erg / s and a dissipation time-scale that is only a factor of 3 larger than the flow crossing time-scale.; Comment: 18 pages, 15 figures, 4 tables, accepted by MNRAS, fixed errors described in erratum

SiO J=5--4 in the HH211 Protostellar Jet Imaged with the SMA

Hirano, Naomi; Liu, Sheng-Yuan; Shang, Hsien; Ho, Paul T. P.; Huang, Hui-Chun; Kuan, Yi-Jehng; McCaughrean, Mark J.; Zhang, Qizhou
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 09/12/2005
Relevância na Pesquisa
55.52%
We have mapped the SiO J=5-4 line at 217GHz from the HH211 molecular outflow with the Submillimeter Array (SMA). The high resolution map (1.6''x0.9'') shows that the SiO J=5-4 emission comes from the central narrow jet along the outflow axis with a width of ~0.8'' (~250 AU) FWHM. The SiO jet consists of a chain of knots separated by 3-4'' (~1000 AU) and most of the SiO knots have counterparts in shocked H_2 emission seen in a new, deep VLT near-infrared image of the outflow. A new, innermost pair of knots are discovered at just +/-2'' from the central star. The line ratio between the SiO J=5-4 data and upper limits from the SiO J=1-0 data of Chandler & Richer (2001) suggests that these knots have a temperature in excess of 300-500 K and a density of (0.5-1) x10^7 cm^{-3}. The radial velocity measured for these knots is ~30 km/s, comparable to the maximum velocity seen in the entire jet. The high temperature, high density, and velocity structure observed in this pair of SiO knots suggest that they are closely related to the primary jet launched close to the protostar.; Comment: 7 pages, 1 table and 4 figures, Accepted for publication in the ApJL

Reanalysis of the (J = 5) state at 592 keV in 180Ta and its role in the neutrino-process nucleosynthesis of 180Ta in supernovae

Hayakawa, T.; Mohr, P.; Kajino, T.; Chiba, S.; Mathews, G. J.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 28/12/2010
Relevância na Pesquisa
55.42%
We analyze the production and freeze-out of the isomer 180Tam in the neutrino-process. We consider the influence of a possible low-lying intermediate (J = 5) state at 592 keV using a transition width estimated from the measured half-life. This more realistic width is much smaller than the previous estimate.We find that the 592-keV state leads only to a small reduction of the residual isomer population ratio from the previous result; that is, considering this better estimate for the transition width, the isomer population ratio changes from R = 0.39 to R = 0.38, whereas previously it was estimated that this transition could reduce the ratio to R = 0.18. This finding strengthens the evidence that 138La and 180Ta are coproduced by neutrino nucleosynthesis with an electron neutrino temperature of kT~4 MeV.; Comment: Published in Physical Review C, 9 Pages, 2 Figures

A New Probe of Dense Gas at High Redshift: Detection of HCO+(5-4) Line Emission in APM 08279+5255

Garcia-Burillo, S.; Gracia-Carpio, J.; Guelin, M.; Neri, R.; Cox, P.; Planesas, P.; Solomon, P. M.; Tacconi, L. J.; Bout, P. A. Vanden
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 25/05/2006
Relevância na Pesquisa
45.55%
We report the detection of HCO+(5-4) emission from the Broad Absorption Line (BAL) quasar APM08279+5255 at z=3.911 based on observations conducted at the IRAM Plateau de Bure interferometer. This represents the first detection of this molecular ion at such a high redshift. The inferred line luminosity, uncorrected for lensing, is L'(HCO+)=(3.5+-0.6)x10^10 Kkms^-1pc^2. The HCO+ J=5-4 source position coincides within the errors with that reported from previous HCN J=5-4 and high-J CO line observations of this quasar. The HCO+ line profile central velocity and width are consistent with those derived from HCN. This result suggests that HCO+(5-4) emission comes roughly from the same circumnuclear region probed by HCN. However, the HCN(5-4)/HCO+(5-4) intensity ratio measured in APM08279+5255 is significantly larger than that predicted by simple radiative transfer models, which assume collisional excitation and equal molecular abundances. This could imply that the [HCN]/[HCO^+] abundance ratio is particularly large in this source, or that the J=5 rotational levels are predominantly excited by IR fluorescent radiation.; Comment: Accepted for publication in ApJ Letters, May 25

A CS J=5-4 Mapping Survey Towards High-mass Star Forming Cores Associated with Water Masers

Shirley, Yancy L.; Evans II, Neal J; Young, Kaisa E.; Knez, Claudia; Jaffe, Daniel T.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 18/08/2003
Relevância na Pesquisa
55.52%
We have mapped 63 regions forming high-mass stars in CS J=5-4 using the CSO. The CS peak position was observed in C34S J=5-4 towards 57 cores and in 13CS J=5-4 towards the 9 brightest cores. The sample is a subset of a sample originally selected toward water masers; the selection on maser sources should favor sources in an early stage of evolution. The integrated intensity of CS J=5-4 correlates very well with the dust continuum emission at 350 microns. The distributions of size, virial mass, surface density, and luminosity are all peaked with a few cores skewed towards much larger values than the mean. We find a weak correlation between C34S linewidth and size, consistent with Dv ~ R^{0.3}. The linewidths are much higher than would be predicted by the usual relations between linewidth and size determined from regions of lower mass. These regions are very turbulent. The derived virial mass agrees within a factor of 2 to 3 with mass estimates from dust emission at 350 microns after corrections for the density structure are accounted for. The resulting cumulative mass spectrum of cores above 1000 solar masses can be approximated by a power law with a slope of about -0.9, steeper than that of clouds measured with tracers of lower density gas and close to that for the total masses of stars in OB associations. The median turbulent pressures are comparable to those in UCHII regions...

Physical characteristics of G331.5-0.1: The luminous central region of a Giant Molecular Cloud

Merello, Manuel; Bronfman, Leonardo; Garay, Guido; Nyman, Lars-Ake; Evans II, Neal J.; Walmsley, C. Malcolm
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 31/05/2013
Relevância na Pesquisa
45.56%
We report molecular line and dust continuum observations toward the high-mass star forming region G331.5-0.1, one of the most luminous regions of massive star-formation in the Milky Way, located at the tangent region of the Norma spiral arm, at a distance of 7.5 kpc. Molecular emission was mapped toward the G331.5-0.1 GMC in the CO (J=1-0) and C18O (J=1-0) lines with NANTEN, while its central region was mapped in CS (J=2-1 and J=5-4) with SEST, and in CS (J=7-6) and 13CO (J=3-2) with ASTE. Continuum emission mapped at 1.2 mm with SIMBA and at 0.87 mm with LABOCA reveal the presence of six compact and luminous dust clumps, making this source one of the most densely populated central regions of a GMC in the Galaxy. The dust clumps are associated with molecular gas and they have the following average properties: size of 1.6 pc, mass of 3.2x10^3 Msun, molecular hydrogen density of 3.7x10^4 cm^{-3}, dust temperature of 32 K, and integrated luminosity of 5.7x10^5 Lsun, consistent with values found toward other massive star forming dust clumps. The CS and 13CO spectra show the presence of two velocity components: a high-velocity component at ~ -89 km s^{-1}, seen toward four of the clumps, and a low-velocity component at ~ -101 km s^{-1} seen toward the other two clumps. Radio continuum emission is present toward four of the molecular clumps...

A CS J = 5 -> 4 Mapping Survey Towards High Mass Star Forming Cores Associated with H2O Masers

Shirley, Yancy L.; Evans II, Neal J.; Mueller, Kaisa E.; Knez, Claudia; Jaffe, Daniel T.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 05/11/2001
Relevância na Pesquisa
55.42%
In this survey we have systematically mapped 63 cloud cores in the CS J = 5 -> 4 line towards a sample of high mass star forming cores with water masers (Plume et al. 1992, Plume et al. 1997) using the CSO. From the CS spectra and maps we determine cloud core sizes, virial masses, a mass spectrum, and a size-linewidth relationship.; Comment: 2 pages to appear in Hot Star Workshop III: The Earliest Phases of Massive Star Birth, ASP Conference Series, 2002, ed. P.A. Crowther

Search for Molecular Gas in the quasar SDSS 1044-0125 at z=5.73

Wilner, D. J.; Wright, M. C. H.; Di Francesco, J.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 12/12/2001
Relevância na Pesquisa
45.55%
We report upper limits on CO J=2--1 and CO J=5--4 emission from the quasar SDSSp J104433.04-012502.2 at z=5.73 from observations made with the Berkeley-Illinois-Maryland-Association Array. Previously reported limits on CO J=6--5 emission (Iwata et al. 2001) were obtained at z=5.80, which is now thought to be off by 1%, and the observations likely missed the relevant redshifts for molecular gas. The new $3\sigma$ upper limits on the line luminosities are $L^{'}_{CO}(2-1) < 5.1 \times 10^{10}$ K km s$^{-1}$ pc$^2$ and $L^{'}_{CO}(5-4) < 3.0 \times 10^{10}$ K km s$^{-1}$ pc$^2$, assuming 200 km s$^{-1}$ linewidth. The CO J=5--4 observations place an upper limit on warm, dense molecular gas mass comparable to amounts derived for some other high redshift quasar systems from detections of this line. The limit on CO J=2--1 emission suggests that excitation bias does not affect this conclusion. In addition, no molecular gas rich companion galaxies are found in a $\sim1.4$ Mpc field surrounding the quasar.; Comment: 9 pages, accepted by The Astronomical Journal

Star formation relations and CO SLEDs across the J-ladder and redshift

Greve, T. R.; Leonidaki, I.; Xilouris, E. M.; Weiss, A.; Zhang, Z. -Y.; van der Werf, P.; Aalto, S.; Armus, L.; Diaz-Santos, T.; Evans, A. S.; Fischer, J.; Gao, Y.; Gonzalez-Alfonso, E.; Harris, A.; Henkel, C.; Meijerink, R.; Naylor, D. A.; Smith, H. A.;
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 16/07/2014
Relevância na Pesquisa
45.51%
We present FIR-CO luminosity relations ($\log L_{\rm FIR} = \alpha \log L'_{\rm CO} + \beta$) for the full CO rotational ladder from J=1-0 to J=13-12 for 62 local (z < 0.1) (Ultra) Luminous Infrared Galaxies (LIRGs) using data from Herschel SPIRE-FTS and ground-based telescopes. We extend our sample to high redshifts (z > 1) by including 35 (sub)-millimeter selected dusty star forming galaxies from the literature with robust CO observations. The addition of luminous starbursts at high redshifts enlarge the range of the FIR-CO luminosity relations towards the high-IR-luminosity end while also significantly increasing the small amount of mid-/high-J CO line data available prior to Herschel. This new data-set (both in terms of IR luminosity and J-ladder) reveals linear FIR-CO luminosity relations ($\alpha \sim 1$) for J=1-0 up to J=5-4, with a nearly constant normalisation ($\beta \sim 2$). This is expected from the (also) linear FIR-(molecular line) relations found for the dense gas tracer lines (HCN and CS), as long as the dense gas mass fraction does not vary strongly within our (merger/starburst)-dominated sample. However from J=6-5 and up to J=13-12 we find an increasingly sub-linear slope and higher normalization constant with increasing J. We argue that these are caused by a warm (~100K) and dense ($>10^4{\rm cm^{-3}}$) gas component whose thermal state is unlikely to be maintained by star formation powered far-UV radiation fields (and thus is no longer directly tied to the star formation rate). We suggest that mechanical heating (e.g....

The role of 5-HT_2C receptors in touchscreen visual reversal learning in the rat: a cross-site study

Alsi?, J.; Nilsson, S. R. O.; Gastambide, F.; Wang, R. A. H.; Dam, S. A.; Mar, A. C.; Tricklebank, M.; Robbins, T. W.
Fonte: Springer Publicador: Springer
Tipo: Article; published version
EN
Relevância na Pesquisa
45.54%
This is the final version of the article. It first appeared from Springer via http://dx.doi.org/10.1007/s00213-015-3963-5; Rationale Reversal learning requires associative learning and executive functioning to suppress non-adaptive responding. Reversal-learning deficits are observed in e.g. schizophrenia and obsessive-compulsive disorder and implicate neural circuitry including the orbitofrontal cortex (OFC). Serotonergic function has been strongly linked to visual reversal learning in humans and experimental animals but less is known about which receptor subtypes are involved. Objectives The objectives of the study were to test the effects of systemic and intra-OFC 5-HT_2C-receptor antagonism on visual reversal learning in rats and assess the psychological mechanisms underlying these effects within novel touchscreen paradigms. Methods In experiments 1?2, we used a novel 3-stimulus task to investigate the effects of 5-HT_2C-receptor antagonism through SB 242084 (0.1, 0.5 and 1.0 mg/kg i.p.) cross-site. Experiment 3 assessed the effects of SB 242084 in 2-choice reversal learning. In experiment 4, we validated a novel touchscreen serial visual reversal task suitable for neuropharmacological microinfusions by baclofen-/muscimol-induced OFC inactivation. In experiment 5...

Star Formation Relations and CO Spectral Line Energy Distributions across the J-ladder and Redshift

Greve, T. R.; Leonidaki, I.; Xilouris, E. M.; Weiß, A.; Zhang, Z.-Y.; van der Werf, P.; Aalto, S.; Armus, L.; Díaz-Santos, T.; Evans, A. S.; Fischer, J.; Gao, Y.; González-Alfonso, E.; Harris, A.; Henkel, C.; Meijerink, R.; Naylor, D. A.; Smith, H. A.;
Fonte: American Astronomical Society Publicador: American Astronomical Society
Tipo: Article; PeerReviewed Formato: application/pdf
Publicado em 20/10/2014
Relevância na Pesquisa
45.53%
We present FIR [50-300 μm]–CO luminosity relations (i.e., log L_FIR = α log L’_co + β) for the full CO rotational ladder from J = 1-0 up to J = 13-12 for a sample of 62 local (z ≤ 0.1) (Ultra) Luminous Infrared Galaxies (LIRGs; L_(IR[8-1000 μm]) > 10^(11) L ☉) using data from Herschel SPIRE-FTS and ground-based telescopes. We extend our sample to high redshifts (z > 1) by including 35 submillimeter selected dusty star forming galaxies from the literature with robust CO observations, and sufficiently well-sampled FIR/submillimeter spectral energy distributions (SEDs), so that accurate FIR luminosities can be determined. The addition of luminous starbursts at high redshifts enlarge the range of the FIR–CO luminosity relations toward the high-IR-luminosity end, while also significantly increasing the small amount of mid-J/high-J CO line data (J = 5-4 and higher) that was available prior to Herschel. This new data set (both in terms of IR luminosity and J-ladder) reveals linear FIR–CO luminosity relations (i.e., α 1) for J = 1-0 up to J = 5-4, with a nearly constant normalization (β ~ 2). In the simplest physical scenario, this is expected from the (also) linear FIR–(molecular line) relations recently found for the dense gas tracer lines (HCN and CS)...