809 research outputs found
Measurements of the cosmic background radiation
Maps of the large scale structure (theta is greater than 6 deg) of the cosmic background radiation covering 90 percent of the sky are now available. The data show a very strong 50-100 sigma (statistical error) dipole component, interpreted as being due to our motion, with a direction of alpha = 11.5 + or - 0.15 hours, sigma = -5.6 + or - 2.0 deg. The inferred direction of the velocity of our galaxy relative to the cosmic background radiation is alpha = 10.6 + or - 0.3 hours, sigma = -2.3 + or - 5 deg. This is 44 deg from the center of the Virgo cluster. After removing the dipole component, the data show a galactic signature but no apparent residual structure. An autocorrelation of the residual data, after substraction of the galactic component from a combined Berkeley (3 mm) and Princeton (12 mm) data sets, show no apparent structure from 10 to 180 deg with a rms of 0.01 mK(sup 2). At 90 percent confidence level limit of .00007 is placed on a quadrupole component
Patterns of antenal sensilla of Panstrongylus megistus from three Brazilian states
The objective of the present study was to analyze and describe the phenotype of the antennal sensilla of Panstrongylus megistus, one of the epidemiologically most important species of triatomines in Brazil. Specimens from the Brazilian states of Goiás (GO), Minas Gerais (MG), and Rio Grande do Sul (RS) were compared, based on studies of four types of sensilla on three antennal segments: thick-walled trichoid (TK), thin-walled trichoid (TH), bristles (BR), and basiconica (BA). Discriminant analysis allowed the separation of the RS specimens from those of GO and MG. Multivariate discriminant analysis demonstrated that the sensilla of males differed from those of females, the variables with greatest weight being the BA of all three segments and the TK of flagellum 1. The basiconica sensilla were significantly more abundant in females, on all three segments. Antennal sensilla patterns also demonstrated significant differences among P. megistus specimens.Fil: Villela, M. M.. Fundación Oswaldo Cruz; BrasilFil: Catala, Silvia Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de Catamarca. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Secretaría de Industria y Minería. Servicio Geológico Minero Argentino. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Provincia de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja; ArgentinaFil: Juberg, J.. Instituto Oswaldo Cruz; Brasil. Fundación Oswaldo Cruz; BrasilFil: Silva, I. G.. Universidade Federal de Goiás; BrasilFil: Dias, J. C. P.. Fundación Oswaldo Cruz; Brasi
Metabolic Factors and Their Influence on the Clinical Course and Response to HCV Treatment
Nowadays, direct-acting antivirals (DAA) have been used for hepatitis C virus (HCV) treatment leading to cure in 90–95% of non-cirrhotic patients depending on genotype, treatment experience, and regimen used. It was observed rates of antiviral response above 90% in compensated cirrhotic patients that should be treated for long time and/or ribavirin may be required. Metabolic syndrome, obesity, and insulin resistance are increasing worldwide and further contribute to hepatic steatosis and have long been recognized as a cause of lipid deposition in the liver. These factors affect the rate of antiviral response to interferon-based therapy, but it seems not impact DAA treatment. The effect of HCV eradication on hepatic steatosis and progression to fibrosis, cirrhosis, and hepatocellular carcinoma warrants further study in the era of direct-acting antivirals. Other factors that could be related to increase liver damage are vitamin D and associated polymorphisms. Patients with low concentration of total vitamin D [25(OH)D] presented high degree of fibrosis and high values of total cholesterol and triglycerides. In this chapter, we review the challenges and metabolic pathology associated with HCV infection and, discuss the influence of some metabolic factors which can cause liver damage
A Spin Modulated Telescope to Make Two Dimensional CMB Maps
We describe the HEMT Advanced Cosmic Microwave Explorer (HACME), a balloon
borne experiment designed to measure sub-degree scale Cosmic Microwave
Background anisotropy over hundreds of square degrees, using a unique two
dimensional scanning strategy. A spinning flat mirror that is canted relative
to its spin axis modulates the direction of beam response in a nearly
elliptical path on the sky. The experiment was successfully flown in February
of 1996, achieving near laboratory performance for several hours at float
altitude. A map free of instrumental systematic effects is produced for a 3.5
hour observation of 630 square degrees, resulting in a flat band power upper
limit of (l(l+1)C_l/2 pi)^0.5 < 77 microK at l = 38 (95% confidence). The
experiment design, flight operations and data, including atmospheric effects
and noise performance, are discussed.Comment: 4 pages, 3 figure
ARCADE 2 Measurement of the Extra-Galactic Sky Temperature at 3-90 GHz
The ARCADE 2 instrument has measured the absolute temperature of the sky at
frequencies 3, 8, 10, 30, and 90 GHz, using an open-aperture cryogenic
instrument observing at balloon altitudes with no emissive windows between the
beam-forming optics and the sky. An external blackbody calibrator provides an
{\it in situ} reference. Systematic errors were greatly reduced by using
differential radiometers and cooling all critical components to physical
temperatures approximating the CMB temperature. A linear model is used to
compare the output of each radiometer to a set of thermometers on the
instrument. Small corrections are made for the residual emission from the
flight train, balloon, atmosphere, and foreground Galactic emission. The ARCADE
2 data alone show an extragalactic rise of mK at 3.3 GHz in addition
to a CMB temperature of K. Combining the ARCADE 2 data with
data from the literature shows a background power law spectrum of [K] from 22 MHz to 10 GHz ( GHz)
in addition to a CMB temperature of K.Comment: 11 pages 5 figures Submitted to Ap
Emissão anômala de micro-ondas na Via Láctea
In this work, it is presented a brief review of the phenomenon known as Anomalous Microwave Emission (AME) in the Milky Way. AME represents an interesting challenge for modern astrophysics. Since the identification of this emission in 1996, and despite several studies dedicated to this subject, no definite explanation has yet been given about the physical mechanisms responsible for such emission.É apresentada uma revisão sucinta do fenômeno conhecido como Emissão Anômala de Micro-ondas na Via Láctea (AME, da sigla em inglês para Anomalous Microwave Emission), que representa um desafio interessante para a astrofísica moderna. Desde a identificação dessa emissão, em 1996, ainda não foi dada uma explicação definitiva sobre os mecanismos físicos responsáveis por tal emissão, apesar dos vários estudos dedicados ao tema
ARCADE 2 Observations of Galactic Radio Emission
We use absolutely calibrated data from the ARCADE 2 flight in July 2006 to
model Galactic emission at frequencies 3, 8, and 10 GHz. The spatial structure
in the data is consistent with a superposition of free-free and synchrotron
emission. Emission with spatial morphology traced by the Haslam 408 MHz survey
has spectral index beta_synch = -2.5 +/- 0.1, with free-free emission
contributing 0.10 +/- 0.01 of the total Galactic plane emission in the lowest
ARCADE 2 band at 3.15 GHz. We estimate the total Galactic emission toward the
polar caps using either a simple plane-parallel model with csc|b| dependence or
a model of high-latitude radio emission traced by the COBE/FIRAS map of CII
emission. Both methods are consistent with a single power-law over the
frequency range 22 MHz to 10 GHz, with total Galactic emission towards the
north polar cap T_Gal = 0.498 +/- 0.028 K and spectral index beta = -2.55 +/-
0.03 at reference frequency 1 GHz. The well calibrated ARCADE 2 maps provide a
new test for spinning dust emission, based on the integrated intensity of
emission from the Galactic plane instead of cross-correlations with the thermal
dust spatial morphology. The Galactic plane intensity measured by ARCADE 2 is
fainter than predicted by models without spinning dust, and is consistent with
spinning dust contributing 0.4 +/- 0.1 of the Galactic plane emission at 22
GHz.Comment: 10 poges, 9 figures. Submitted to The Astrophysical Journa
Induced defense responses in tomato against bacterial spot by proteins synthesized by endophytic bacteria.
Some endophytes can synthesize molecules that elicit the induction of plant resistance to infection by pathogens. The objective of this study was to demonstrate that protein fractions 42 and 75 from Bacillus amyloliquefaciens and Bacillus pumilus were capable of acting as elicitors of induced resistance in tomato plants against Xanthomonas vesicatoria, following partial resolution by gel-filtration chromatography. Tomato plants sprayed with protein fractions 42 and 75 reduced, respectively, 63.5 and 56.6% of bacterial spot, compared with control plants. Additionally, these fractions promoted the increase of peroxidase (POX) and polyphenol oxidase (PPO) enzyme activities in treated plants. In SDS-PAGE stained with silver nitrate, protein fractions 42 and 75 appeared as simple bands with estimated molecular mass of 28 and 43 kDa, respectively. We report the partial characterization of two macromolecules synthesized by endophytic bacteria that act as elicitors of systemic resistance in tomato against X. vesicatoria
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