770 research outputs found
Seyfert Activity and Nuclear Star Formation in the Circinus Galaxy
We present high angular resolution (0".15-0".5) near infrared images and
spectroscopy of the Circinus galaxy, the closest Seyfert 2 galaxy known. The
data reveal a non-stellar nuclear source at 2.2 microns. The coronal line
region and the hot molecular gas emission extend for 20-50 pc in the ionization
cone. The data do not show evidence for a point-like concentration of dark
mass; we set an upper limit of 4*10^6 Mo to the mass of a putative black hole.
We find evidence for a young nuclear stellar population, with typical ages
between 4*10^7 and 1.5*10^8 yrs. The luminosity of the starburst inside a few
hundred pc is comparable to the intrinsic luminosity of the Seyfert nucleus,
and the two of them together account for most of the observed bolometric
luminosity of the galaxy. Within the central 12 pc the starburst has an age of
about 7*10^7 yrs and radiates about 2% of the luminosity of the active nucleus.
We discuss the implications of these results for models that have been proposed
for the starburst-AGN connection.Comment: 44 pages, Latex (including 11 Figures), Color Figures 1, 2 and 4 are
available at http://www.arcetri.astro.it/~maiolino/ , ApJ in pres
Is there a Supermassive Black Hole at the Center of the Milky Way?
This review outlines the observations that now provide an overwhelming
scientific case that the center of our Milky Way Galaxy harbors a supermassive
black hole. Observations at infrared wavelength trace stars that orbit about a
common focal position and require a central mass (M) of 4 million solar masses
within a radius of 100 Astronomical Units. Orbital speeds have been observed to
exceed 5,000 km/s. At the focal position there is an extremely compact radio
source (Sgr A*), whose apparent size is near the Schwarzschild radius
(2GM/c^2). This radio source is motionless at the ~1 km/s level at the
dynamical center of the Galaxy. The mass density required by these observations
is now approaching the ultimate limit of a supermassive black hole within the
last stable orbit for matter near the event horizon.Comment: Invited review submitted to International Journal of Modern Physics
D; 23 pages; 10 figure
The Effect of Smoking and Body Mass Index on The Complication Rate of Alloplastic Breast Reconstruction
Background and Aims: The aim of this study was to evaluate the effect of smoking and body mass index on the occurrence of complications after alloplastic breast reconstruction. Materials and Methods: A consecutive series of 56 patients treated with immediate or delayed alloplastic breast reconstruction, including six cases combined with latissimus dorsi flap, at three hospitals between 2012 and 2018 were included. Complications were scored and defined according to Clavien–Dindo. To evaluate the impact of smoking, body mass index, and other potential risk factors on the occurrence of any and severe complications, univariate and multivariate logistic regression analyses were applied to estimate odds ratios and 95% confidence intervals. Results: In 56 patients, 22 patients had a complication. As much as 46% of smokers had severe complications compared to 18% of non-smokers. Of patients with body mass index ⩾ 25, 40% had severe complications compared to 10% with body mass index < 25. Smokers had eight times more chance of developing severe complications than non-smokers (ORadjusted = 8.0, p = 0.02). Patients with body mass index ⩾ 25 had almost 10 times more severe complications compared to patients with body mass index ⩽ 25 (ORadjusted = 9.9, p = 0.009). No other risk factors were significant. Conclusion: Smoking and body mass index ⩾ 25 both increased the complication rate to such an extent that patients should be informed about their increased risk for complications following alloplastic breast reconstruction and on these grounds surgeons may delay alloplastic breast reconstruction. It is an ethical dilemma whether one should deny overweight and obese patients and those who smoke an immediate alloplastic breast reconstruction. For both life style interventions, adequate guidance should be made available
DIGESTIBILITY OF NUTRIENTS WITH THE INCLUSION OF CONJUGATED LINOLEIC ACID IN THE DIET OF DOGS
The inclusion of the conjugated linoleic acid (CLA) in food for dogs has been displaying greatpotential, taking into account several benefits in regard to the use of this product. To determine the effect of CLAon the digestibility of the dry matter, nutrients and energy in dogs, two experiments were performed using dogs ofBeagle type, in the age of seven and 15 months, respectively. The experimental diets were isonutritive, justdiffering by the inclusion of CLA, watching for the addition to the control-diet, of an amount of lipids in the form ofchicken fat equivalent to the amount of CLAadded (0.3%), so that the diets were isoenergetic. The coefficients ofapparent digestibility of the dry matter, crude protein, ethereal extract and nitrogen-free extract were not affectedby the inclusion of conjugated linoleic acid, showing that the addition of the product did not interfere with theprocess of digestion of nutrients. In both digestibility experiments, higher values of metabolizable energy wereobserved for the diets with inclusion of CLA(P < 0.01) when compared with the control-diet.A inclusão do ácido linoléico conjugado (CLA) em rações para cães tem apresentado grandepotencial, tendo em vista os vários benefícios relacionados à utilização deste produto. Para determinar o efeitodo CLA sobre a digestibilidade da matéria seca, nutrientes e energia em cães foram realizados dois ensaiosutilizando cães da raça Beagle, com sete e 15 meses de idade. As dietas experimentais eram isonutritivas,diferindo apenas quanto à inclusão de CLA, tomando-se o cuidado de acrescentar à dieta controle umaquantidade de lipídeos na forma de gordura de frango equivalente à quantidade de CLAadicionada (0,3%), paraque as dietas fossem isoenergéticas. Os coeficientes de digestibilidade aparente da matéria seca, proteínabruta, extrato etéreo e extrativos não nitrogenados não foram afetados pela inclusão de ácido linoléicoconjugado, mostrando que a adição do produto não interferiu no processo de digestão dos nutrientes. Emambos os ensaios de digestibilidade, observaram-se valores de energia metabolizável superiores para asdietas com inclusão de CLA(P<0,01) quando comparada com a dieta controle
Outcome of Quality of Life for Women Undergoing Autologous versus Alloplastic Breast Reconstruction following Mastectomy:A Systematic Review and Meta-Analysis
Background: This review aimed to meta-analyze the quality of life of alloplastic versus autologous breast reconstruction, when measured with the BREAST-Q. Methods: An electronic PubMed and EMBASE search was designed to find articles that compared alloplastic versus autologous breast reconstruction using the BREAST-Q. Studies that failed to present BREAST-Q scores and studies that did not compare alloplastic versus autologous breast reconstruction were excluded. Two authors independently extracted data from the included studies. A standardized data collection form was used. Quality was assessed using the Newcastle-Ottawa Scale. The mean difference and 95 percent confidence intervals between breast reconstruction means were estimated for each BREAST-Q subscale. Forest plots and the I2statistic were used to assess heterogeneity and funnel plot publication bias. The Z test was used to assess overall effects. Results: Two hundred eighty abstracts were found; 10 articles were included. Autologous breast reconstruction scored significantly higher in the five subscales than alloplastic breast reconstruction. The Satisfaction with Breasts subscale indicated the greatest difference, with a mean difference of 6.41 (95 percent CI, 3.58 to 9.24; I2= 70 percent). The Satisfaction with Results subscale displayed a mean difference of 5.52. The Sexual Well-Being subscale displayed a mean difference of 3.85. The Psychosocial Well-Being subscale displayed a mean difference of 2.64. The overall difference in physical well-being was significant, with high heterogeneity (mean difference, 3.33; 95 percent CI, 0.18 to 6.48; I2= 85). Conclusion: Autologous breast reconstruction had superior outcomes compared with alloplastic breast reconstruction as measured by the BREAST-Q
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