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Efeito da temperatura sobre a expressão de fatores miogênicos no músculo estriado esquelético do pacu (Piaractus mesopotamicus)

Paula, Tassiana Gutierrez de
Fonte: Universidade Estadual Paulista (UNESP) Publicador: Universidade Estadual Paulista (UNESP)
Tipo: Dissertação de Mestrado Formato: 79 f.
POR
Relevância na Pesquisa
16.61%
Pós-graduação em Biologia Geral e Aplicada - IBB; Muscle growth in teleost fish involves the balance between the recruitment (hyperplasia) and the enlargement (hypertrophy) of muscle fibers, mechanisms that are controlled by many transcription factors, as the MyoD family and growth factors as myostatin. Several environmental factors such as temperature can influence the muscle fiber cellularity, and the expression of genes related with muscle development and growth, affecting the growth rate pattern in fish. Pacu is a fast growing fish extensively used in Brazilian aquaculture programs and shows a wide range of thermal tolerance. As temperature is an environmental factor that influences the fish growth rate, parameter directly related with muscle plasticity and growth, we hypothesized that different rearing temperatures in juvenile of pacu, which presents an intense muscle growth by hyperplasia, can potentially alter the muscle cellularity that could influence the muscle growth patterns in this species. The aim of this study is to analyze the muscle growth characteristics and the expression of Myogenic Regulatory Factors, MyoD and myogenin, and the growth factor myostatin in juvenile of pacu (Piaractus mesopotamicus) submitted to the different rearing temperatures. Juvenile fish (1.5 g weight) were distributed in tanks containing water and maintained at 24 (G24)...

Rearing temperature induces changes in muscle growth and gene expression in juvenile pacu (Piaractus mesopotamicus)

Paula, Tassiana Gutierrez de; Alves de Almeida, Fernanda Losi; Carani, Fernanda Regina; Vechetti-Junior, Ivan Jose; Padovani, Carlos Roberto; Simoes Salomao, Rondinelle Arthur; Mareco, Edson Assuncao; Santos, Vander Bruno dos; Dal-Pai-Silva, Maeli
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 31-37
ENG
Relevância na Pesquisa
18.03%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Processo FAPESP: 11/14538-7; Pacu (Piaractus mesopotamicus) is a fast-growing fish that is extensively used in Brazilian aquaculture programs and shows a wide range of thermal tolerance. Because temperature is an environmental factor that influences the growth rate of fish and is directly related to muscle plasticity and growth, we hypothesized that different rearing temperatures in juvenile pacu, which exhibits intense muscle growth by hyperplasia, can potentially alter the muscle growth patterns of this species. The aim of this study was to analyze the muscle growth characteristics together with the expression of the myogenic regulatory factors MyoD and myogenin and the growth factor myostatin in juvenile pacu that were submitted to different rearing temperatures. Juvenile fish (1.5 g weight) were distributed in tanks containing water and maintained at 24 degrees C (G24), 28 degrees C (G28) and 32 degrees C (G32) (three replicates for each group) for 60 days. At days 30 and 60, the fish were anesthetized and euthanized, and muscle samples (n = 12) were collected for morphological, morphometric and gene expression analyses. At day 30...

Signalling with Dividends? New Evidence from Europe

Vieira, Elisabete Fátima Simões
Fonte: Instituto Universitário de Lisboa Publicador: Instituto Universitário de Lisboa
Tipo: Tese de Doutorado
Publicado em 27/11/2007 ENG
Relevância na Pesquisa
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JEL Classification: G35, G32; The dividend policy is one of the most debated topics in the finance literature. One of the different lines of research on this issue is based on the information content of dividends, which has motivated a significant amount of theoretical and empirical research. According to dividend signalling hypothesis, dividend change announcement trigger share returns because they convey information about management’s assessment of firms’ future prospects. An interesting issue, not yet explored, is the empirical evidence of an adverse market reaction to dividend changes. We analyse the classical assumptions of dividend signalling hypothesis. The evidence gives no support for a positive relation between dividend change announcements and the market reaction for French firms, and only a weak support for the Portuguese and UK firms. After accounting for non-linearity in the mean reversion process, the global results do not give support to the assumption that dividend announcements are positively related with future earnings changes. Nevertheless, we found some evidence, especially in the UK market, of the window dressing phenomenon and the maturity hypothesis. We introduce a new approach to investigate the relationship between the market reaction to dividend changes and future earnings changes with the purpose of understanding why the market sometimes reacts negatively (positively) to dividend increases (decreases). Moreover...

A gestão do risco na indústria da aviação: o caso da Jet Fuel

Subhaschandra, Dhiren
Fonte: Instituto Universitário de Lisboa Publicador: Instituto Universitário de Lisboa
Tipo: Dissertação de Mestrado
Publicado em 04/03/2008 POR
Relevância na Pesquisa
16.61%
J.E.L. classification: G32, G39; In the current context of great uncertainty, risk management has assumed an important role in the organizations. The actual environment of fierce competition and the volatility associated with financial markets and commodities prices have led to an increasing search of the derivatives. This thesis intends to approach the risk that the airlines face due to the instability of the oil market. Jet fuel is one of the most important costs that airlines support, being in some cases the biggest cost. To achieve a discount in the unit cost of jet fuel relative to the market price can mean an excellent competitive advantage against the other competitors in the aviation business. Lufthansa is known as one of the best airline carrier in terms of managing the risk of jet fuel price. Using the German company as an example, this study describes how to develop a strategy to manage efficiently the risk of jet fuel and to assess the impact in the accounts of the company.; No actual contexto de grande incerteza, a gestão de risco tem assumido um papel cada vez mais importante nas organizações. O clima de concorrência feroz e a volatilidade associada aos mercados financeiros e aos preços das commodities têm levado a uma procura crescente dos derivados. Este trabalho pretende abordar o risco que as companhias de aviação correm face à instabilidade do mercado petrolífero. O jet fuel é um dos custos mais relevantes que uma empresa de transporte aéreo suporta...

How profitability and debt influence dividends’ payout policy in the U.K., France and Portugal

Moitinho, Ricardo João Martins Pereira
Fonte: Instituto Universitário de Lisboa Publicador: Instituto Universitário de Lisboa
Tipo: Dissertação de Mestrado
Publicado em //2008 ENG
Relevância na Pesquisa
16.61%
JEL Classifications: G32 – Financing Policy; Financial Risk and Risk Management; Capital and Ownership Structure; G35 - Payout Policy;; The goal of this thesis is to investigate how profitability and debt influence the dividends’ payout policy of companies of three European countries: Portugal, France and the U.K. Using work of La Porta et al. (2000) as a starting point, this thesis not only validates the “outcome model“ described by La Porta et al. (2000) but also finds two factors that affect dividends’ payout level: debt and activity type. By comparing companies’ dividend payout policy in the three countries, this thesis confirms that the U.K., a common law country, has the highest dividends level and that dividend payout policy is a consequence of effective investor protection by law, as claimed by La Porta et al. (2000). This thesis also subscribes the latter’s idea that in common law countries, fast growth firms pay lower dividends than slow growth firms, meaning that protected shareholders are willing to wait for their dividends when investment opportunities are good. Poorly protected investors seem to take whatever dividends they can get, regardless of investment opportunities. Testing the factors that might affect dividend payout level indicates that there is a positive relation between debt level and dividend policy...

Hedging foreign currency and interest rate risks with derivatives: how much does it increase the firm’s value?

Cunha, Florbela Galvão da
Fonte: Instituto Universitário de Lisboa Publicador: Instituto Universitário de Lisboa
Tipo: Dissertação de Mestrado
Publicado em //2009 ENG
Relevância na Pesquisa
16.61%
Mestrado em Finanças / JEL Classification: F30; G32; Traditional finance theory suggests that a company can’t increase its value by changing the riskiness. However, recent studies show that it is possible to increase the firm’s value using hedging instruments. In my research I pretend to show that hedging with derivatives increases firm’s value, as already have been demonstrated in several different markets. The sample includes the 336 non-financial firms quoted in Lisbon, Madrid and Milan stock markets at the end of 2006. This study presents empirical evidence on the valuation effects of Foreign Currency (FC) and Interest Rate (IR) hedging with derivatives, measured by Tobin’s Q. Depending on the Tobin’s Q definition, I found a 4.48%, 8.92% or 11.88% significant premium for derivative hedging firms. I also found that 91.1% hedging firms are derivative users. Sample was separate in Iberian Market (Lisbon and Madrid stock markets) and Italian (Milan stock market) subsamples. Statistical and regression methods evidence that to the Iberian firms hedging activity has more impact on firm’s value than to Italian ones. Results evidence important statistical significant premiums for foreign currency and interest rate derivative hedgers in Iberian Market...

Aumento de capital e emissão de direitos: o caso do BPI, S.A. em 2008

Nascimento, Mafalda Sofia Domingues
Fonte: Instituto Universitário de Lisboa Publicador: Instituto Universitário de Lisboa
Tipo: Dissertação de Mestrado
Publicado em //2009 POR
Relevância na Pesquisa
16.61%
Mestrado em Finanças / Classificação JEL: G21 – Banks; G32 – Capital and Owership Structure; Esta dissertação apresenta um case study sobre o aumento de capital do Banco BPI, S.A, o qual decorreu entre Maio e Junho de 2008. O seu objectivo é, por um lado, perceber as razões e as circunstâncias do aumento, e por outro, determinar qual seria a altura e condições mais adequadas para realizar o mesmo, assim como se o valor dos direitos foi correctamente avaliado. O Grupo BPI, liderado pelo Banco BPI, é o 4.º maior grupo financeiro privado Português. De forma a sustentar o crescimento da actividade do Grupo BPI e garantir os objectivos definidos na política de dividendos de longo prazo, o Banco BPI anunciou, em 23 de Abril de 2008, um aumento de capital de 760 milhões para 900 milhões de euros. O aumento teve como destinatários os accionistas do BPI, através da emissão de direitos. Em Junho de 2008, este aumento foi totalmente subscrito. De forma a avaliar a opção call e os respectivos direitos, utilizou-se o modelo Black-Scholes (1973). Adicionalmente, com base na metodologia de Brown e Warner (1981), é apresentado um breve event study para analisar a reacção do mercado ao anúncio de aumento do capital. Os resultados desta dissertação permitem concluir que...

Avaliação da tomada firme de seis emissões de direitos no Canadá

Seatra, João André da Silva
Fonte: Instituto Universitário de Lisboa Publicador: Instituto Universitário de Lisboa
Tipo: Dissertação de Mestrado
Publicado em //2009 POR
Relevância na Pesquisa
16.61%
Mestrado em Finanças / JEL Classification System: G13 - Contingent Pricing; Future Pricing; G32 - Financing Policy; Financial Risk and Risk Management; Capital and Ownership Structure; Este trabalho irá centrar-se nas emissões de direitos com tomada firme no Canadá e respectiva avaliação. O principal objectivo será analisar a tomada firme e verificar a hipótese de overpriced. Pretendemos ainda identificar empresas que tenham comprometido os fundos da emissão num projecto arriscado, de forma a aplicarmos o modelo de Anjos (2009) e analisar alguns dados adicionais não incorporados nos modelos, para percebermos se, independentemente da tomada firme estar over ou underpriced, os valores exigidos pelos underwriters são de facto justificáveis. Quanto à estrutura do trabalho, após a revisão literária, definiremos a amostra, que será composta por seis prospectos de emissões de direitos com tomada firme, realizadas por diferentes empresas canadianas. Posteriormente, face aos dois métodos de avaliação de opções que pretendemos utilizar, seleccionaremos a informação de cada prospecto que nos permitirá distinguir as emissões em que será possível utilizar, além do modelo de Black e Scholes (1973), também o modelo de Anjos (2009). Para a aplicação destes modelos...

Comparative neurovirulence of selected vesicular stomatitis virus temperature-sensitive mutants of complementation groups II and III.

Rabinowitz, S G; Huprikar, J; Dal Canto, M C
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /07/1981 EN
Relevância na Pesquisa
17.22%
Weanling mice were inoculated intracerebrally with selected vesicular stomatitis virus (VSV) complementation group II and III temperature-sensitive (ts) mutants. Of the VSV ts mutants studied, only ts G32, a group III complementation mutant, appeared neurovirulent. Interestingly, neither the capacity to replicate in central nervous system tissue nor the ability to replicate in certain neurally derived continuous cell lines at semipermissive or nonpermissive temperatures appeared different among the VSV ts mutants employed. Finally, the pathological alterations in central nervous system tissue produced by VSV ts G32 were entirely different than those produced by G31 VSV ts in the group III mutant. These studies support the hypothesis that both the virological and neuropathological features produced by different VSV ts mutants are dependent upon the unique characteristics of each mutant, rather than upon a common biochemical defect shared by all members of a complementation group.

Murine central nervous system infection by a viral temperature-sensitive mutant: a subacute disease leading to demyelination.

Dal Canto, M. C.; Rabinowitz, S. G.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /03/1981 EN
Relevância na Pesquisa
17.22%
Temperature-sensitive (ts) mutants of viruses may represent an important mechanism for viral persistence. Ts mutants of different complementation groups of vesicular stomatitus virus (VSV) have shown various disease patterns in infected mice which were at variance with the clinical and pathologic features of wild-type virus infection. To investigate whether neurovirulence of different ts mutants was dependent on the individual mutant or on the biochemical defect(s) common to all members of a complementation group, we infected mice with ts G32 VSV, a mutant of the same complementation group III as the previously described ts G31 VSV. Pathologic changes in infected mice were sharply different from those produced by ts G31 VSV and actually similar to those produced by ts G41 VSV, a member of Complementation Group IV, also previously described. These results suggest that the biologic behavior of ts mutants is dependent on the individual characteristics of each mutant. The most important alterations by ts G32 VSV were in the white matter of brain and spinal cord, where extensive inflammatory demyelination was observed. Lack of inflammation and demyelination in similarly infected nude mice would suggest that, in this infection, demyelination is produced by the host immune response rather than by direct viral myelinolytic activity. Such findings are similar to those we described in other viral infections and support the hypothesis of a common host-mediated pathway leading to demyelination in a variety of unrelated viral infections. These conclusions may have relevance to human demyelinating diseases.

Salivaricin G32, a Homolog of the Prototype Streptococcus pyogenes Nisin-Like Lantibiotic SA-FF22, Produced by the Commensal Species Streptococcus salivarius

Wescombe, Philip A.; Dyet, Kristin H.; Dierksen, Karen P.; Power, Daniel A.; Jack, Ralph W.; Burton, Jeremy P.; Inglis, Megan A.; Wescombe, Anna L.; Tagg, John R.
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
27.96%
Salivaricin G32, a 2667 Da novel member of the SA-FF22 cluster of lantibiotics, has been purified and characterized from Streptococcus salivarius strain G32. The inhibitory peptide differs from the Streptococcus pyogenes—produced SA-FF22 in the absence of lysine in position 2. The salivaricin G32 locus was widely distributed in BLIS-producing S. salivarius, with 6 (23%) of 26 strains PCR-positive for the structural gene, slnA. As for most other lantibiotics produced by S. salivarius, the salivaricin G32 locus can be megaplasmid encoded. Another member of the SA-FF22 family was detected in two Streptococcus dysgalactiae of bovine origin, an observation supportive of widespread distribution of this lantibiotic within the genus Streptococcus. Since the inhibitory spectrum of salivaricin G32 includes Streptococcus pyogenes, its production by S. salivarius, either as a member of the normal oral microflora or as a commercial probiotic, could serve to enhance protection of the human host against S. pyogenes infection.

Influência do nitrogênio adicionado por SHTPN na resistência à erosão por cavitação do aço inoxidável martensítico

Maftoum, Ricardo de Almeida
Fonte: Curitiba Publicador: Curitiba
Tipo: Dissertação de Mestrado
POR
Relevância na Pesquisa
17.22%
Several studies are being done to improve the cavitation erosion resistance of steel. Among those studies, is the use of steels with nitrogen enriched surfaces. In this study the use of SHTPN (Solution Heat Treatment after Plasma Nitriding) technique was studied, which consists in performing plasma nitriding, used to add nitrogen to the material, followed by a solubilization treatment so that the nitrogen is in solid solution. On this experiment two martensitic stainless steel were used (ASTM CA-6NM and ASM 15-5PH). Nitriding was performed at 630°C for 3 hours. Three different solubilization conditions were used for CA6NM steel (1100°C for 1 hour, NS1, 1200°C for 30 minutes, NS2 and 1200° for 1 hour, NS3). Only one condition was used for 15-5PH steel (1200°C por 30 minutos, NS), and later used an aging treatment (390°C for 8 hours, NSE). The samples were analyzed through x-ray diffraction, optical microscopy and microhardness profiles. All CA6NM samples had an increase in surface hardness, and no big austenite presence was observed. On 15-5PH steel, an austenictic phase was observed. The cavitation test was conducted according to ASTM G32/09 standard, but using the indirect method. The damaged area of the samples was analyzed by scanning electron microscopy. The treatment increased cavitation erosion resistance of all samples...

Influência das condições de processo sobre as descontinuidades e resistência à cavitação de revestimentos soldados sobre aço CA-6NM

Beiler, Denilson Rogério
Fonte: Florianópolis Publicador: Florianópolis
Tipo: Dissertação de Mestrado Formato: 509 p.| il., grafs., tabs.
POR
Relevância na Pesquisa
17.22%
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia Mecânica; A erosão por cavitação causa enormes prejuízos para as empresas geradoras de energia elétrica, pois compromete o funcionamento de turbinas hidráulicas e leva a constantes paradas para recuperação das regiões erodidas. Um dos materiais atualmente mais empregados na fabricação de rotores de turbinas hidráulicas é o aço inoxidável martensítico CA-6NM, que tem melhor soldabilidade que a dos aços martensíticos convencionais, devido ao baixo teor de carbono. Além disso, possui ótimas propriedades mecânicas e boa resistência à erosão por cavitação. Quando é necessário recuperar uma região erodida por cavitação, é feita a deposição por soldagem de ligas resistentes, notadamente aquelas à base de cobalto. Para evitar a formação de trincas no depósito, geralmente é depositada uma camada de amanteigamento de um material menos propenso ao trincamento e que possua alta ductilidade, como o aço inox austenítico. Entretanto, em locais onde houve pouca erosão, não há espaço suficiente para depositar o amanteigamento. Nestes casos, deposita-se a liga direto sobre o substrato...

Influência do boro na resistência à cavitação de revestimentos processados com pós atomizados e com misturas mecânicas de pós elementares de Fe-Cr-Mn-Si-B

Cruz, Juliane Ribeiro da
Fonte: Universidade Federal do Paraná Publicador: Universidade Federal do Paraná
Tipo: Dissertação Formato: 118f. : il. algumas color., tabs., grafs.; application/pdf
PORTUGUêS
Relevância na Pesquisa
17.22%
Orientadora: Profª. Drª. Ana Sofia Clímaco Monteiro d'Oliveira; Orientador: Prof. Dr. Sérgio Luiz Henke; Dissertação (mestrado) - Universidade Federal do Paraná, Setor de Tecnologia, Programa de Pós-Graduação em Engenharia e Ciência dos Materiais - PIPE. Defesa: Curitiba, 24/10/2014; Inclui referências; Área de concentração: Engenharia e ciência de materiais; Resumo: Turbinas hidráulicas sujeitas à cavitação requerem intervenções periódicas para recuperação do perfil das pás pela deposição de materiais resistentes à cavitação na região erodida. Um desempenho competitivo pode ser alcançado com ligas austeníticas Fe-Cr-Mn-Si-B, resistentes à cavitação. Uma análise preliminar foi realizada por meio do estudo de revestimentos processados com misturas mecânicas de pós elementares com quatro diferentes teores de boro. A validação dos resultados observados foi realizada por meio do estudo de revestimentos processados com ligas atomizadas. Para a deposição em substrato de AISI 304 foi usado o processo plasma a arco transferido. A caracterização microestrutural dos revestimentos incluiu a análise do refino dendrítico (microscopia ótica), da quantidade de eutético (microscopia quantitativa), das fases formadas (difração de raios-X e espectroscopia de energia dispersiva) e da microdureza Vickers. Foram determinados a resistência à cavitação (conforme norma ASTM G32-10)...

The velocity structure of the cometary H II regions G13.87+0.28, G32.80+ 0.19B, and G61,48+0.09B1

Lizano, Susana; Gómez, Yolanda; Garay Brignardello, Guido Alejandro
Fonte: Universidade do Chile Publicador: Universidade do Chile
Tipo: Artículo de revista
EN_US
Relevância na Pesquisa
27.53%
Artículo de publicación ISI; We present H92alpha radio recombination line and radio continuum observations toward three cometary-like H II regions, G13.87 + 0.28, G32.80 + 0.19B, and G61.48 + 0.09B1, with an angular resolution of approximately 2''. The kinematics (H92alpha velocity and line-width fields) and morphology (continuum maps) of the ionized gas from two of these sources, G32.80 + 0.19B and G61.48 + 0.09B1, are best explained by models in which the ionized gas is expanding in an anisotropic medium (champagne models), whereas that of G13.87 + 0.28 can be well explained in terms of a bow shock formed by the stellar wind of a massive star moving supersonically through a molecular cloud. As predicted theoretically, we find that at the frequency of the H92alpha line non-LTE effects are significant, particularly for the compact, high emission measure H II regions we detected in the direction of two cometary regions.

Warm molecular gas associated with cometary Hıı regions

Gómez, Yolanda; Lizano, Susana; Garay Brignardello, Guido Alejandro
Fonte: The American Astronomical Society Publicador: The American Astronomical Society
Tipo: Artículo de revista
EN
Relevância na Pesquisa
17.22%
Artículo de publicación ISI; We present observations of the (J, K) = (2, 2) and (3, 3) inversion transitions of ammonia, made at ˜4" resolution with the VLA, in the direction of the G32.80 + 0.19 and G61.48 + 0.09 star-forming regions, which contain cometary-like and compact H II regions. Our data reveal the presence, in both complexes, of compact ammonia structures, with sizes of ˜0.2 pc, which are intimately associated with the regions of ionized gas. The ammonia clumps have excitation temperatures in the range 60-80 K and molecular hydrogen densities in the range (0.7-5) × 104 cm-3. We suggest that these warm ammonia clumps correspond to compact molecular structures, embedded within more extended molecular clouds, which have been heated by the radiation from the star that ionizes the associated H II region and possibly compressed by the shocks driven by the expansion of the H II region. We find that the molecular clumps associated with the cometary-like H II regions are located near the head of the ionized region and have line-center velocities similar to those of the ionized gas at the head position. These results imply that the cometary H II regions studied here, which exhibit strong gradients in the line- center velocities along their symmetry axis...

Distances to Two Galactic Supernova Remnants: G32.8-0.1 and G346.6-0.2

Xu, Jian-Wen; Zhang, Hui-Rong
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 02/09/2009
Relevância na Pesquisa
27.22%
There are either a near kinematic distance of 5.5 kpc or a far distance of 8.8 kpc for a Galactic supernova remnant (SNR) G32.8$-$0.1 derived by using the rotation curve of the Galaxy. Here we make sure that the remnant distance is the farther one 8.8 kpc through solving a group of equations for the shell-type remnants separately at the adiabatic-phase and the radiative-phase. For SNR G346.6$-$0.2 we determine its distance also the farther one 11 kpc rather than the nearer one 5.5 kpc.; Comment: 5 pages, 3 figures

First detection of the Methylidyne cation (CH+) fundamental rotational line with the Herschel/SPIRE FTS

Naylor, D. A.; Dartois, E.; Habart, E.; Abergel, A.; Baluteau, J. -P.; Jones, S. C.; Polehampton, E.; Ade, P.; Anderson, L. D.; André, P.; Arab, H.; Bernard, J. -P.; Blagrave, K.; Boulanger, F.; Cohen, M.; Compiègne, M.; Cox, P.; Davis, G.; Emery, R.; F
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 11/05/2010
Relevância na Pesquisa
17.22%
Aims. To follow the species chemistry arising in diverse sources of the Galaxy with Herschel. Methods. SPIRE FTS sparse sampled maps of the Orion bar & compact HII regions G29.96-0.02 and G32.80+0.19 have been analyzed. Results. Beyond the wealth of atomic and molecular lines detected in the high-resolution spectra obtained with the FTS of SPIRE in the Orion Bar, one emission line is found to lie at the position of the fundamental rotational transition of CH+ as measured precisely in the laboratory (Pearson & Drouion 2006). This coincidence suggests that it is the first detection of the fundamental rotational transition of CH+. This claim is strengthened by the observation of the lambda doublet transitions arising from its relative, CH, which are also observed in the same spectrum. The broad spectral coverage of the SPIRE FTS allows for the simultaneous measurement of these closely related chemically species, under the same observing conditions. The importance of these lines are discussed and a comparison with results obtained from models of the Photon Dominated Region (PDR) of Orion are presented. The CH+ line also appears in absorption in the spectra of the two galactic compact HII regions G29.96-0.02 and G32.80+0.19, which is likely due to the presence of CH+ in the the Cold Neutral Medium of the galactic plane. These detections will shed light on the formation processes and on the existence of CH+...

XMM-Newton Observations of G32.45+0.1and G38.55+0.0: diffuse hard X-ray sources found with the ASCA Galactic Plane Survey

Yamaguchi, Hiroya; Ueno, Masaru; Koyama, katsuji; bamba, Aya; Yamauchi, Shigeo
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 01/10/2004
Relevância na Pesquisa
27.96%
We report on XMM-Newton observations of G32.45+0.1 and G38.55+0.0. These were discovered as diffuse hard X-ray sources with the ASCA Galactic plane survey, but the limited spatial resolution of ASCA could not conclude whether these are truly diffuse or a group of unresolved point-sources. XMM-Newton, with higher spatial resolution than ASCA, confirmed that G32.45+0.1 has a diffuse shell-like structure with a radius of ~4'. The spectrum shows featureless continuum, hence can be fitted with a power-law model of Gamma ~2.2 with an absorption of N_H~5.2*10^{22}cm^{-2}. From this N_H value, we estimate the distance to G32.45+0.1 to be ~17kpc, then the luminosity (in the 0.5-10.0keV band) and radius of the shell are ~9.5*10^{34}ergs/s and ~20pc, respectively. The radio complex sources in the NRAO/VLA Sky Survey (NVSS; 1.4GHz) are globally associated to the X-ray shell of G32.45+0.1. Therefore G32.45+0.1 is likely to be a synchrotron dominant shell-like SNR. No significant diffuse structure was found in the XMM-Newton image of another ASCA diffuse source G38.55+0.0. The upper limit of the observed flux (0.5-10.0keV) is estimated to be 9.0*10^{-13}ergs/cm^2/s being consistent with the ASCA result.; Comment: Accepted for publication in Publications of the Astronomical Society of Japan...

Shock-Excited Maser Emission from Supernova Remnants: G32.8-0.1, G337.8-0.1, G346.6-0.2, and the HB3/W3 Complex

Koralesky, Barron; Frail, D. A.; Goss, W. M.; Claussen, M. J.; Green, A. J.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 29/05/1998
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We present the results of VLA observations in the ground-state hydroxyl (OH) transition at 1720 MHz toward 20 supernova remnants (SNRs). We detect compact emission from four objects. For three of these objects (G32.8-0.1, G337.8-0.1, and G346.6-0.2), we argue that the emission results from masers which are shock-excited due to the interaction of the SNR and an adjacent molecular cloud. We observe a characteristic Zeeman profile in the Stokes V spectrum, which allows us to derive a magnetic field of 1.5 and 1.7 mG for G32.8-0.1 and G346.6-0.2, respectively. The velocity of the masers also allows us to determine a kinematic distance to the SNR. Our criteria for a maser to be associated with an SNR along the line of sight are that the position and velocity of the maser and SNR must agree, and the OH(1720) emission must be unaccompanied by other OH lines.; Comment: Accepted to the Astronomical Journal (19 pages total, 6 figures, 4 tables)