890 research outputs found
Maternal and cord blood betatrophin (angiopoietin-like protein 8) in pregnant women with gestational diabetes and normoglycemic controls: A systematic review, meta-analysis, and meta-regression
Aims: This systematic review and meta-analysis examined maternal and cord blood betatrophin levels in pregnant women with gestational diabetes mellitus (GDM) and normoglycemic controls.
Material and Methods: PubMed, Cochrane Library, Embase, LILACS, WangFang, and China National Knowledge Infrastructure were searched for literature from inception until May 2022. The primary outcomes were maternal and cord blood betatrophin levels. A random-effect meta-analysis was used to estimate the pooled results. The mean differences (MDs) or standardised MDs (SMD) and their 95% confidence intervals (CIs) were calculated. I2 tests were used to evaluate the heterogeneity. The quality of studies was evaluated using the Newcastle–Ottawa Scale.
Results: Betatrophin levels were reported in 22 studies with a total of 3034 pregnant women, and in seven studies including cord blood from 456 infants. Women with GDM display higher betatrophin levels than the normoglycemic controls (SMD = 0.85, 95% CI: 0.38–1.31) during the second half of the pregnancy. The sensitivity analysis indicated that no single study had significantly influenced the betatrophin overall outcomes. There was heterogeneity between the studies as evidenced by high I2 values. Meta-regression analysis indicated a significant regression coefficient for maternal betatrophin and glycosilated haemoglobin. There was no significant difference in cord blood betatrophin in infants from women with and without GDM (SMD = 0.34, 95% CI: −0.15–0.83). Women with GDM also had significantly higher insulin, glucose, glycosylated haemoglobin, HOMA-IR, LDL-cholesterol, HDL-cholesterol, triglycerides, and body mass index compared with the normoglycemic controls.
Conclusions: Maternal betatrophin levels were higher in women with GDM than in the normoglycemic controls. There was no difference in cord blood betatrophin
Transient interference of transmission and incidence
Due to a transient quantum interference during a wavepacket collision with a
potential barrier, a particular momentum, that depends on the potential
parameters but is close to the initial average momentum, becomes suppressed.
The hole left pushes the momentum distribution outwards leading to a
significant constructive enhancement of lower and higher momenta. This is
explained in the momentum complex-plane language in terms of a saddle point and
two contiguous ``structural'' poles, which are not associated with resonances
but with incident and transmitted components of the wavefunction.Comment: 4 pages of text, 6 postscript figures, revte
Etiopathogenesis of ovarian cancer. An inflamm-aging entity?
Ovarian cancer is one of the most common gynecologic cancers and has the highest mortality rate. The risk/protective factors of ovarian cancer suggest that its etiology is multifactorial. Several factors are involved in age-related increases in carcinogenesis, including the accumulation of senescent cells, inflammaging (a chronic inflammatory state that persists in the elderly), and immunosenescence (aging of the immune system) changes associated with poor immune surveillance. At sites of inflammation, exposure to high levels of inflammatory mediators, such as reactive oxygen species, cytokines, prostaglandins, and growth factors, contributes to increased cell division and genetic and epigenetic changes. These exposure-induced changes promote excessive cell proliferation, increased survival, malignant transformation, and cancer development. Furthermore, the proinflammatory tumor microenvironment contributes to ovarian cancer metastasis and chemoresistance. This narrative review of the literature was carried out to delineate the possible role of inflammaging in the etiopathogenesis of ovarian cancer development. We discuss the current carcinogenic hypotheses, sites of origin, and etiological factors of ovarian cancer. Treatment of inflammation may represent an attractive strategy for both the prevention and therapy of ovarian cancer. © 2022 The Author(s
Avaliação da Lista de Controle de Regulação da Emoção para Crianças e Adolescentes
Emotion regulation during childhood and adolescence has implications in different areas, both in these stages and in adult life. The objective of this article was to evaluate an emotional regulation test, Emotional Regulation Checklist (ERC), using CET-R as a frame of reference. We analyzed 71 articles that used the ERC for the evaluation of emotional regulation. The information was sorted according to test description, reliability and validity. All reliability results were shown using the Cronbach alpha coefficient. In relation to validity the average of the ERC correlations with the criteria was adequate but with some shortcomings. It is advisable to conduct research using advanced psychometric models.Durante la infancia y la adolescencia la regulación de las emociones tiene repercusiones en diferentes ámbitos, tanto en estas etapas como en la vida adulta. El objetivo de este artículo fue evaluar un test de regulación emocional, Emotional Regulation Checklist (ERC), utilizando el CET-R como marco de referencia. Se analizaron 71 artículos que emplearon el ERC para la evaluación de la regulación emocional. La información se clasificó teniendo en cuenta la descripción del test, su fiabilidad y validez. Todos los resultados de fiabilidad se mostraron mediante el coeficiente alfa de Cronbach. En relación a la validez, fue adecuado el promedio de las correlaciones del ERC con sus criterios, pero con algunas carencias. Es recomendable plantear investigaciones con modelos psicométricos avanzados.A regulação das emoções na infância e adolescência tem implicações em diferentes áreas, tanto nestas fases como na vida adulta. O objetivo deste artigo foi avaliar um teste de regulação emocional, Emotional Regulation Checklist (ERC), usando o CET-R como marco de referência. Foram analisados 71 artigos que utilizaram o ERC para a avaliação da regulação emocional. A informação foi classificada de acordo com a descrição do teste, confiabilidade e validade. Todos os resultados de confiabilidade foram mostrados usando o coeficiente alfa Cronbach. Em relação à validade, a média das correlações do ERC com os critérios foi adequada, mas com algumas falhas. É aconselhável a realização de pesquisas utilizando modelos psicométricos avançados
3D Hydrodynamical Simulations of Surface Convection in Red Giant Stars. Impact on spectral line formation and abundance analysis
We investigate the impact of 3D hydrodynamical model atmospheres of red giant
stars at different metallicities on the formation of spectral lines of a number
of ions and molecules. We carry out realistic 3D simulations of surface
convection in red giant stars with varying stellar parameters. We use the
simulations as time-dependent hydrodynamical model stellar atmospheres to
compute atomic (Li, O, Na, Mg, Ca, Fe) and molecular (CH, NH, OH) spectral
lines under the assumption of local thermodynamic equilibrium (LTE). We compare
the line strengths computed in 3D with the results of analogous line formation
calculations for 1D, hydrostatic, plane-parallel MARCS model atmospheres in
order to estimate the impact of 3D models on the derivation of elemental
abundances. The temperature and density inhomogeneities and correlated
velocities in 3D models, as well as the differences between the 1D and mean 3D
structures significantly affect the predicted line strengths. Under the
assumption of LTE, the low atmospheric temperatures of very metal-poor 3D model
atmospheres cause the lines from neutral species and molecules to appear
stronger than in 1D. Therefore, elemental abundances derived from these lines
using 3D models are significantly lower than according to 1D analyses.
Differences between 3D and 1D abundances of C, N, and O derived from CH, NH,
and OH weak low-excitation lines are found to be in the range -0.5 dex to -1.0
dex for the the red giant stars at [Fe/H]=-3 considered here. At this
metallicity, large negative corrections (about -0.8 dex) are also found for
weak low-excitation Fe I lines. We caution, however, that departures from LTE
might be significant for these and other elements and comparable to the effects
due to stellar granulation.Comment: Accepted for publication on A&A, 23 pages, 15 figure
Nuclear astrophysics with radioactive ions at FAIR
The nucleosynthesis of elements beyond iron is dominated by neutron captures in the s and r processes. However, 32 stable, proton-rich isotopes cannot be formed during those processes, because they are shielded from the s-process flow and r-process beta-decay chains. These nuclei are attributed to the p and rp process. For all those processes, current research in nuclear astrophysics addresses the need for more precise reaction data involving radioactive isotopes. Depending on the particular reaction, direct or inverse kinematics, forward or time-reversed direction are investigated to determine or at least to constrain the desired reaction cross sections. The Facility for Antiproton and Ion Research (FAIR) will offer unique, unprecedented opportunities to investigate many of the important reactions. The high yield of radioactive isotopes, even far away from the valley of stability, allows the investigation of isotopes involved in processes as exotic as the r or rp processes
High-resolution optical imaging of the core of the globular cluster M15 with FastCam
We present high-resolution I-band imaging of the core of the globular cluster
M15 obtained at the 2.5 m Nordic Optical Telescope with FastCam, a low readout
noise L3CCD based instrument. Short exposure times (30 ms) were used to record
200000 images (512 x 512 pixels each) over a period of 2 hours 43 min. The
lucky imaging technique was then applied to generate a final image of the
cluster centre with FWHM ~ 0".1 and 13" x 13" FoV. We obtained a catalogue of
objects in this region with a limiting magnitude of I=19.5. I-band photometry
and astrometry are reported for 1181 stars. This is the deepest I-band
observation of the M15 core at this spatial resolution. Simulations show that
crowding is limiting the completeness of the catalogue. At shorter wavelengths,
a similar number of objects has been reported using HST/WFPC observations of
the same field. The cross-match with the available HST catalogues allowed us to
produce colour-magnitude diagrams where we identify new Blue Straggler star
candidates and previously known stars of this class.Comment: 11 pages, 15 figures. Accepted for publication in Monthly Notices of
the Royal Astronomical Societ
New ATLAS9 And MARCS Model Atmosphere Grids for the Apache Point Observatory Galactic Evolution Experiment (APOGEE)
We present a new grid of model photospheres for the SDSS-III/APOGEE survey of
stellar populations of the Galaxy, calculated using the ATLAS9 and MARCS codes.
New opacity distribution functions were generated to calculate ATLAS9 model
photospheres. MARCS models were calculated based on opacity sampling
techniques. The metallicity ([M/H]) spans from -5 to 1.5 for ATLAS and -2.5 to
0.5 for MARCS models. There are three main differences with respect to previous
ATLAS9 model grids: a new corrected H2O linelist, a wide range of carbon
([C/M]) and alpha element [alpha/M] variations, and solar reference abundances
from Asplund et al. 2005. The added range of varying carbon and alpha element
abundances also extends the previously calculated MARCS model grids. Altogether
1980 chemical compositions were used for the ATLAS9 grid, and 175 for the MARCS
grid. Over 808 thousand ATLAS9 models were computed spanning temperatures from
3500K to 30000K and log g from 0 to 5, where larger temperatures only have high
gravities. The MARCS models span from 3500K to 5500K, and log g from 0 to 5.
All model atmospheres are publically available online.Comment: 8 pages, 6 figures, 5 tables, accepted for publication in The
Astronomical Journa
High contrast optical imaging of companions: the case of the brown dwarf binary HD-130948BC
High contrast imaging at optical wavelengths is limited by the modest
correction of conventional near-IR optimized AO systems.We take advantage of
new fast and low-readout-noise detectors to explore the potential of fast
imaging coupled to post-processing techniques to detect faint companions to
stars at small separations. We have focused on I-band direct imaging of the
previously detected brown dwarf binary HD130948BC,attempting to spatially
resolve the L2+L2 benchmark system. We used the Lucky-Imaging instrument
FastCam at the 2.5-m Nordic Telescope to obtain quasi diffraction-limited
images of HD130948 with ~0.1" resolution.In order to improve the detectability
of the faint binary in the vicinity of a bright (I=5.19 \pm 0.03) solar-type
star,we implemented a post-processing technique based on wavelet transform
filtering of the image which allows us to strongly enhance the presence of
point-like sources in regions where the primary halo dominates. We detect for
the first time the BD binary HD130948BC in the optical band I with a SNR~9 at
2.561"\pm 0.007" (46.5 AU) from HD130948A and confirm in two independent
dataset that the object is real,as opposed to time-varying residual speckles.We
do not resolve the binary, which can be explained by astrometric results
posterior to our observations that predict a separation below the NOT
resolution.We reach at this distance a contrast of dI = 11.30 \pm 0.11, and
estimate a combined magnitude for this binary to I = 16.49 \pm 0.11 and a I-J
colour 3.29 \pm 0.13. At 1", we reach a detectability 10.5 mag fainter than the
primary after image post-processing. We obtain on-sky validation of a technique
based on speckle imaging and wavelet-transform processing,which improves the
high contrast capabilities of speckle imaging.The I-J colour measured for the
BD companion is slightly bluer, but still consistent with what typically found
for L2 dwarfs(~3.4-3.6).Comment: accepted in A\&
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