Context.
The zone of avoidance (ZoA) does not allow for clear optical observations of extragalactic sources behind the Milky Way due to the meaningful extinction of the optical emission of these ...objects. Observations in near-infrared (NIR) wavelengths represent a potential source of astronomical discoveries that support the detection of new galaxies and potentially complete the picture of the large-scale structures in this as-yet poorly explored area of the sky.
Aims.
Our aim is to decipher the nature of the overdensity located behind the Milky Way in tile b204 of the VISTA Variables in Vía Láctea (VVV) survey.
Methods.
We studied an area of six arcmin around a galaxy concentration located at
l
= 354.82° and
b
= −9.81°. We selected five galaxies, taking into account the source distribution on the sky to optimise the requested time for the observations, and we obtained the spectra with Flamingos 2 long-slit spectrograph at Gemini South 8.1-meter telescope. To identify and characterise the absorption features, we fit the galaxies underlying spectrum using the
STARLIGHT
code together with the IRTF stellar library. In addition, the spectroscopic findings are reinforced using complementary photometric techniques such as red-sequence and photometric redshift estimation.
Results.
The mean spectroscopic redshift estimated from the NIR spectra is
z
= 0.225 ± 0.014. This value presents a good agreement with that obtained from photometric analysis,
photoz
= 0.21 ± 0.08, and the probability distribution function of the galaxies in the studied region. Also, the red-sequence slope is consistent with the one expected for NIR observations of galaxy clusters.
Conclusions.
The redshifts obtained from both, photometric and spectroscopic techniques are in good agreement, allowing for the confirmation of the nature of this structure at
z
= 0.225 ± 0.014, thereby unveiling a new galaxy cluster, VVVGCl-B J181435-381432, behind the Milky Way bulge.
Abstract
The most reliable single-epoch supermassive black hole mass (
M
BH
) estimates in quasars are obtained by using the velocity widths of low-ionization emission lines, typically the H
β
λ
4861 ...line. Unfortunately, this line is redshifted out of the optical band at
z
≈ 1, leaving
M
BH
estimates to rely on proxy rest-frame ultraviolet (UV) emission lines, such as C
iv
λ
1549 or Mg
ii
λ
2800, which contain intrinsic challenges when measuring, resulting in uncertain
M
BH
estimates. In this work, we aim at correcting
M
BH
estimates derived from the C
iv
and Mg
ii
emission lines based on estimates derived from the H
β
emission line. We find that employing the equivalent width of C
iv
in deriving
M
BH
estimates based on Mg
ii
and C
iv
provides values that are closest to those obtained from H
β
. We also provide prescriptions to estimate
M
BH
values when only C
iv
, only Mg
ii
, and both C
iv
and Mg
ii
are measurable. We find that utilizing both emission lines, where available, reduces the scatter of UV-based
M
BH
estimates by ∼15% when compared to previous studies. Lastly, we discuss the potential of our prescriptions to provide more accurate and precise estimates of
M
BH
given a much larger sample of quasars at 3.20 ≲
z
≲ 3.50, where both Mg
ii
and H
β
can be measured in the same near-infrared spectrum.
We present spectroscopic measurements for 226 sources from the Gemini Near Infrared Spectrograph-Distant Quasar Survey (GNIRS-DQS). Being the largest uniform, homogeneous survey of its kind, it ...represents a flux-limited sample (mi 19.0 mag, H 16.5 mag) of Sloan Digital Sky Survey (SDSS) quasars at 1.5 z 3.5 with a monochromatic luminosity ( ) at 5100 in the range of 1044-1046 erg s−1. A combination of the GNIRS and SDSS spectra covers principal quasar diagnostic features, chiefly the C iv λ1549, Mg ii λλ2798, 2803, Hβ λ4861, and O iii λλ4959, 5007 emission lines, in each source. The spectral inventory will be utilized primarily to develop prescriptions for obtaining more accurate and precise redshifts, black hole masses, and accretion rates for all quasars. Additionally, the measurements will facilitate an understanding of the dependence of rest-frame ultraviolet-optical spectral properties of quasars on redshift, luminosity, and Eddington ratio, and test whether the physical properties of the quasar central engine evolve over cosmic time.
Galectin (Gal)-1, an endogenous lectin found at sites of immune privilege, plays a critical role in the regulation of the immune response. Therapeutic administration of Gal-1 or its genetic delivery ...suppresses chronic inflammation in experimental models of autoimmunity. The purpose of this work was to investigate the occurrence of circulating anti-Gal-1 antibodies in patients with autoimmune and infectious uveitis as potential determinant factors of disease progression.
IgG, IgE, and IgA anti-Gal-1 antibodies were assessed by ELISA and Western blot in sera from patients with autoimmune (n = 47) and infectious (n = 15) uveitis compared with healthy control subjects (n = 30). The frequency of anti-Gal-1 antibodies was examined in patients experiencing poor clinical outcome (n = 21) or good evolution (n = 9). Anti-Gal-1 antibodies were eluted by incubating patient sera with nitrocellulose filters adsorbed with rGal-1. The ability of these antibodies to recognize retinal tissue was assessed by ELISA, Western blot, and immunohistochemistry.
IgE, IgG, and IgA anti-Gal-1 antibodies were increased in sera from patients with autoimmune uveitis (P < 0.001 vs. controls) and toxoplasmic retinochoroiditis (P < 0.001). The level of anti-Gal-1 IgE and IgG antibodies was associated with progressive disease and poor outcome in autoimmune and infectious uveitis. Furthermore, these antibodies strongly immunoreacted with retinal lysates and recognized retinal structures mainly photoreceptors in retinal sections.
Anti-retinal Gal-1 antibodies are present in sera from patients with uveitis and can be associated with the progression of ocular disease, suggesting their potential use in follow-up observations of these patients.
Context. The ZOA does not allow clear optical observations of extragalactic sources behind the Milky Way due to the meaningful extinction of the optical emission of these objects. The observations in ...NIR wavelengths represent a potential source of astronomical discoveries supporting the detection of new galaxies, completing the picture of the large scale structure in this still little explored area of the sky. Aims. Our aim is to decipher the nature of the overdensity located behind the Milky Way, in the tile b204 of the VVV survey. Methods. We studied an area of six arcmin around a galaxy concentration located at l = 354.82{\deg} and b = -9.81{\deg}. We selected five galaxies taking into account the source distribution on the sky, in order to optimise the requested time for the observations, and we obtained the spectra with Flamingos 2 long-slit spectrograph at Gemini South 8.1-meter telescope. To identify and characterise the absorption features we have fitted the galaxies underlying spectrum using the starlight code together with the IRTF stellar library. In addition, the spectroscopic findings are reinforced using complementary photometric techniques such as red-sequence and photometric redshift estimation. Results. The mean spectroscopic redshift estimated from the NIR spectra is z = 0.225 +- 0.014. This value presents a good agreement with that obtained from photometric analysis, photoz = 0.21 +- 0.08, and the probability distribution function of the galaxies in the studied region. Also, the red-sequence slope is consistent with the one expected for NIR observations of galaxy clusters. Conclusions. The redshifts obtained from both, photometric and spectroscopic techniques are in good agreement allowing the confirmation of the nature of this structure at z = 0.225 +- 0.014, unveiling a new galaxy cluster, VVVGCl-B J181435-381432, behind the Milky Way bulge.
The most reliable single-epoch supermassive black hole mass (\(M_{\rm BH}\)) estimates in quasars are obtained by using the velocity widths of low-ionization emission lines, typically the H\(\beta\) ...\(\lambda4861\) line. Unfortunately, this line is redshifted out of the optical band at \(z\approx1\), leaving \(M_{\rm BH}\) estimates to rely on proxy rest-frame ultraviolet (UV) emission lines, such as C IV \(\lambda1549\) or Mg II \(\lambda2800\), which contain intrinsic challenges when measuring, resulting in uncertain \(M_{\rm BH}\) estimates. In this work, we aim at correcting \(M_{\rm BH}\) estimates derived from the C IV and Mg II emission lines based on estimates derived from the H\(\beta\) emission line. We find that employing the equivalent width of C IV in deriving \(M_{\rm BH}\) estimates based on Mg II and C IV provides values that are closest to those obtained from H\(\beta\). We also provide prescriptions to estimate \(M_{\rm BH}\) values when only C IV, only Mg II, and both C IV and Mg II are measurable. We find that utilizing both emission lines, where available, reduces the scatter of UV-based \(M_{\rm BH}\) estimates by \(\sim15\%\) when compared to previous studies. Lastly, we discuss the potential of our prescriptions to provide more accurate and precise estimates of \(M_{\rm BH}\) given a much larger sample of quasars at \(3.20 \lesssim z \lesssim 3.50\), where both Mg II and H\(\beta\) can be measured in the same near-infrared spectrum.
We present a comprehensive study of the massive binary system HM1~8, based on
multi-epoch high resolution spectroscopy, $V$-band photometry and archival
X-ray data. Spectra from the OWN Survey, a ...high resolution optical monitoring
of Southern O and WN stars, are used to analyse the spectral morphology and
perform quantitative spectroscopic analysis of both stellar components. The
primary and secondary components are classified as O4.5~IV(f) and O9.7~V,
respectively. From a radial-velocity (RV) study we derived a set of orbital
parameters for the system. We found an eccentric orbit ($e=0.14 \pm 0.01$) with
a period of $P = 5.87820 \pm 0.00008$~days. Through the simultaneous analysis
of the RVs and the $V$-band light curve we derived an orbital inclination of
$70.0^{\circ} \pm 2.0$ and stellar masses of
$M_a=33.6^{+1.4}_{-1.2}~\text{M}_{\sun}$ for the primary, and
$M_b=17.7^{+0.5}_{-0.7}~\text{M}_{\sun}$ for the secondary. The components show
projected rotational velocities $v_1\sin{i}=105 \pm 14~\text{km~s}^{-1}$ and
$v_2\sin{i}=82 \pm 15~\text{km~s}^{-1}$, respectively. A tidal evolution
analysis is also performed and found to be in agreement with the orbital
characteristics. Finally, the available X-ray observations show no evidence of
a colliding winds region, therefore the X-ray emission is attributed to stellar
winds.
Purpose
To introduce, develop, and evaluate a novel denoising technique for diffusion MRI that leverages nonlinear redundancy in the data to boost the SNR while preserving signal information.
Methods
...We exploit nonlinear redundancy of the dMRI data by means of kernel principal component analysis (KPCA), a nonlinear generalization of PCA to reproducing kernel Hilbert spaces. By mapping the signal to a high‐dimensional space, a higher level of redundant information is exploited, thereby enabling better denoising than linear PCA. We implement KPCA with a Gaussian kernel, with parameters automatically selected from knowledge of the noise statistics, and validate it on realistic Monte Carlo simulations as well as with in vivo human brain submillimeter and low‐resolution dMRI data. We also demonstrate KPCA denoising on multi‐coil dMRI data.
Results
SNR improvements up to 2.7× were obtained in real in vivo datasets denoised with KPCA, in comparison to SNR gains of up to 1.8× using a linear PCA denoising technique called Marchenko‐Pastur PCA (MPPCA). Compared to gold‐standard dataset references created from averaged data, we showed that lower normalized root mean squared error was achieved with KPCA compared to MPPCA. Statistical analysis of residuals shows that anatomical information is preserved and only noise is removed. Improvements in the estimation of diffusion model parameters such as fractional anisotropy, mean diffusivity, and fiber orientation distribution functions were also demonstrated.
Conclusion
Nonlinear redundancy of the dMRI signal can be exploited with KPCA, which allows superior noise reduction/SNR improvements than the MPPCA method, without loss of signal information.
Five-year invasive disease–free survival was similar among postmenopausal women with hormone-receptor–positive, HER2-negative breast cancer, one to three positive axillary lymph nodes, and a 21-gene ...recurrence score of 25 or lower who received endocrine-only therapy and those who received chemoendocrine therapy. In premenopausal women, chemoendocrine therapy significantly improved outcomes.
Fibroelastoma papilar pediculado en ventrículo derecho Ferrero, Lucas; Paolantonio, Franco; Milicich, Gabriel A ...
Revista del Consejo Argentino de Residentes de Cardiología,
02/2021, Letnik:
35, Številka:
155
Journal Article
Odprti dostop
Los tumores cardíacos son una patología infrecuente en la práctica cotidiana, siendo 20 a 40 veces más habitual los tumores secundarios. Dentro de los tumores primarios, los benignos son los más ...frecuentes y dentro de estos encontramos a los mixomas, lipomas, fibromas y fibroelastoma, llevándose la mayor frecuencia el mixoma y el fibroelastoma papilar en adultos. Desde la incorporación del ecocardiograma como método complementario de control de pacientes asintomáticos, estos han aumentado su frecuencia.Se presenta el caso clínico de un paciente con fibroelastoma papilar con localización en ventrículo derecho, localización atípica de estos tumores, en quien se decidió realizar resección quirúrgica.
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