5,382 research outputs found
Optical doping and damage formation in AIN by Eu implantation
AlN films grown on sapphire were implanted with 300 keV Eu ions to fluences from 3×1014 to 1.4×1017 atoms/cm2 in two different geometries: “channeled” along the c-axis and “random” with a 10° angle between the ion beam and the surface normal. A detailed study of implantation damage accumulation is presented. Strong ion channeling effects are observed leading to significantly decreased damage levels for the channeled implantation within the entire fluence range. For random implantation, a buried amorphous layer is formed at the highest fluences. Red Eu-related photoluminescence at room temperature is observed in all samples with highest intensities for low damage samples (low fluence and channeled implantation) after annealing. Implantation damage, once formed, is shown to be stable up to very high temperatures.FCT - POCI/FIS/57550/2004FCT - PTDC/FIS/66262/2006FCT - PTDC/CTM/100756/200
Metallicity of M dwarfs III. Planet-metallicity and planet-stellar mass correlations of the HARPS GTO M dwarf sample
Aims. The aim of this work is the study of the planet-metallicity and the
planet-stellar mass correlations for M dwarfs from the HARPS GTO M dwarf
subsample
Methods. We use a new method that takes advantage of the HARPS
high-resolution spectra to increase the precision of metallicity, using
previous photometric calibrations of [Fe/H] and effective temperature as
starting values.
Results. In this work we use our new calibration (rms = 0.08 dex) to study
the planet-metallicity relation of our sample. The well-known correlation for
Giant planet FGKM hosts with metallicity is present. Regarding Neptunians and
smaller hosts no correlation is found but there is a hint that an
anti-correlation with [Fe/H] may exist. We combined our sample with the
California Planet Survey late-K and M-type dwarf sample to increase our
statistics but found no new trends. We fitted a power law to the frequency
histogram of the Jovian hosts for our sample and for the combined sample, f_p =
C10^\alpha[Fe/H], using two different approaches: a direct bin fitting and a
bayesian fitting procedure. We obtained a value for C between 0.02 and 0.04 and
for \alpha between 1.26 and 2.94.
Regarding stellar mass, an hypothetical correlation with planets was
discovered, but was found to be the result of a detection bias.Comment: Accepted for publication in A&A. 18 pages, 11 Figures, 12 Table
Metallicity of M dwarfs IV. A high-precision [Fe/H] and Teff technique from high-resolution optical spectra for M dwarfs
Aims. In this work we develop a technique to obtain high precision
determinations of both metallicity and effective temperature of M dwarfs in the
optical.
Methods. A new method is presented that makes use of the information of 4104
lines in the 530-690 nm spectral region. It consists in the measurement of
pseudo equivalent widths and their correlation with established scales of
[Fe/H] and .
Results. Our technique achieves a of 0.080.01 for [Fe/H],
9113 K for , and is valid in the (-0.85, 0.26 dex), (2800, 4100
K), and (M0.0, M5.0) intervals for [Fe/H], and spectral type
respectively. We also calculated the RMSE which estimates uncertainties
of the order of 0.12 dex for the metallicity and of 293 K for the effective
temperature. The technique has an activity limit and should only be used for
stars with . Our method is available
online at \url{http://www.astro.up.pt/resources/mcal}.Comment: Accepted in Astronomy and Astrophysics. Updated one important
reference in the introduction. Some typos correcte
Co‐existing monophasic teratoma and uterine adenocarcinoma in a female dog
Ovarian teratomas are occasionally reported in dogs; the rarest type is the monophasic teratoma,composed of tissues originating from only one germ layer. Canine endometrial adenocarcinomas are also rare in dogs and mainly affect geriatric females.
This report describes case of co-existing ovarian teratoma and uterine adenocarcinoma in a 10-year old nulliparous female Boxer presented with lethargy, anorexia and purulent vaginal discharge.
Abdominal ultrasonography evidenced pyometra and a mass in the left ovary. This was composed of
a uniform whitish tissue with multiple cystic structures. The histology revealed an atrophy of the ovarian parenchyma, compressed by a proliferation of well-differentiated nervous tissue staining positively to vimentin, S100 and neuronal specific enolase (NSE), and negatively to keratin and inhibin. The left uterine horn, whose diameter was markedly increased, showed foci of endometrial cellular atypia, evident nucleoli and mitoses, at light microscopy.
To our best knowledge, this is the first report of a coexisting ovarian monophasic teratoma and
endometrial adenocarcinoma, two rare reproductive neoplasia in dogs
Functionalizing self-assembled GaN quantum dot superlattices by Eu-implantation
Self-assembled GaN quantum dots (QDs) stacked in superlattices (SL) with AlN spacer layers were implanted with Europium ions to fluences of 1013, 1014, and 1015 cm−2. The damage level introduced in the QDs by the implantation stays well below that of thick GaN epilayers. For the lowest fluence, the structural properties remain unchanged after implantation and annealing while for higher fluences the implantation damage causes an expansion of the SL in the [0001] direction which increases with implantation fluence and is only partly reversed after thermal annealing at 1000 °C. Nevertheless, in all cases, the SL quality remains very good after implantation and annealing with Eu ions incorporated preferentially into near-substitutional cation sites. Eu3+ optical activation is achieved after annealing in all samples. In the sample implanted with the lowest fluence, the Eu3+ emission arises mainly from Eu incorporated inside the QDs while for the higher fluences only the emission from Eu inside the AlN-buffer, capping, and spacer layers is observed.
© 2010 American Institute of PhysicsFCT-PTDC/CTM/100756/2008program PESSOA EGIDE/GRICESFCT-SFRH/BD/45774/2008FCT-SFRH/BD/44635/200
Importance of immunogenicity testing for cost-effective management of psoriasis patients treated with adalimumab
INTRODUCTION:
Up to 30% of patients treated with anti-tumor necrosis factor drugs do not respond adequately, and up to 50% lose response over time. Immunogenicity is now known to be one of the main causes of this loss of response.
METHODS:
Serum levels of adalimumab and anti-drug antibodies (ADAs) were measured in 19 patients with psoriasis.
RESULTS:
Eighty-nine percent of the patients were responders (Psoriasis Area Severity Index (PASI) > 75) and 11% were partial responders (PASI 50-75). The serum levels of adalimumab were lower than the cutoff in both of the partial responders and the ADAs were high, whereas the other 17 patients had adalimumab levels above the cutoff and low ADA levels. Both partial responders were obese and none of them were taking methotrexate. Both patients switched to ustekinumab, and a PASI 90 response was observed after 16 weeks.
CONCLUSION:
Immunogenicity is a risk of biological drugs. In this work, the detection of low levels of adalimumab and high levels of ADAs using a sandwich ELISA correlated with loss of clinical response. Testing immunogenicity and the drug pharmacokinetics of biological drugs in psoriasis patients will probably be part of the daily management of these patients in the future.info:eu-repo/semantics/publishedVersio
Immunological Reconstitution Inflammatory Syndrome and Thrombotic Microangiopathy: Severe Complications in a Child With Acquired Immunodeficiency Syndrome
Some patients with human immunodeficiency virus (HIV) infection deteriorate shortly after starting highly
active antiretroviral therapy (HAART), the so-called immunological reconstitution inflammatory syndrome
(IRIS).1 Although having a spontaneous resolution in many instances, it can be fatal.1 Worse prognosis is seen
in younger children, severe immunosuppression and central nervous system IRIS, or infections with specific
agents, namely, Criptococcus.2 Hemophagocytic lymphohistiocytosis (HLH) has also been described in
children with HIV infection, in the context of an immunological system dysregulation.3 Thrombotic microangiopathy (TMA) became rare with the introduction of HAART, being mostly associated with advanced disease.4 HIV-associated TMA has specific clinical aspects as well as a worse prognosis than idiopathic or congenital TMA.4-9 The authors present the case of a 10-month-old boy with advanced HIV infection who developed IRIS complicated with HLH and TMA during the course of his treatment.info:eu-repo/semantics/publishedVersio
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