282 research outputs found
Reproduction of the azooxanthellate coral Caryophyllia inornata is not affected by temperature along an 850 km gradient on the Western Italian coast
The Intergovernmental Panel on Climate Change (IPCC) predicted that ocean surface
temperature will rise of 0.6–2.0◦C by 2100. Ocean warming is expected to produce
strong impacts on marine ecosystems such as coral reefs, affecting their physiological
events including reproductive processes. To date, relatively few studies have examined
the effects of climate change on the reproductive success of temperate corals
and even less in the azooxanthellate ones. This study examined the reproductive
output of the azooxanthellate Mediterranean coral Caryophyllia inornata along a wide
latitudinal gradient of seawater temperature and solar radiation. A total of 260 samples,
collected from five populations along the Western Italian coast, have been analyzed
through histological techniques. The intriguing aspects characterizing all populations
of C. inornata along the latitudinal gradient are a strong male-biased sex ratio and
the presence of embryos in all stages of development throughout the year in females,
males, and sexually inactive individuals. This peculiarity could suggest a mixed strategy
of sexual and asexual reproduction in this species as has been observed for some
anemones of the genus Actinia. Fecundity and spermary abundance (i.e., the number
of reproductive elements per body volume unit), gonadal index (i.e., the percentage of
body volume occupied by the germ cells) and fertility (i.e., the number of embryos per
body volume unit) in females, males and sexually inactive individuals were unrelated
to solar radiation and temperature along the latitudinal gradient. These results suggest
that the reproduction in C. inornata is not affected by increasing solar radiation and
temperature. The lack of zooxanthellae could make this species less dependent on
these environmental parameters, as previously hypothesized for another azooxanthellate
species, Leptopsammia pruvoti, investigated along the same gradient
Taste intensity and hedonic responses to simple beverages in gastrointestinal cancer patients
Changes in the taste of food have been implicated as a potential cause of reduced dietary intake among cancer patients. However, data on intensity and hedonic responses to the four basic tastes in cancer are scanty and contradictory. The present study aimed at evaluating taste intensity and hedonic responses to simple beverages in 47 anorectic patients affected by gastrointestinal cancer and in 55 healthy subjects. Five suprathreshold concentrations of each of the four test substances (sucrose in black current drinks, citric acid in lemonade, NaCl in unsalted tomato juice, and urea in tonic water) were used. Patients were invited to express a judgment of intensity and pleasantness ranging from 0 to 10. Mean intensity scores directly correlated with concentrations of sour, salty, bitter, and sweet stimuli, in both normals and those with cancer. Intensity judgments were higher in cancer patients with respect to sweet (for median and high concentrations, P < 0.05), salty (for all concentrations, P < 0.05), and bitter tastes (for median concentration, P < 0.01). Hedonic function increased with the increase of the stimuli only for the sweet taste. A negative linear correlation was found between sour, bitter, and salty concentrations and hedonic score. Both in cancer patients and in healthy subjects, hedonic judgments increased with the increase of the stimulus for the sweet taste (r 1/4 0.978 and r 1/4 0.985, P 1/4 0.004 and P 1/4 0.002, respectively), and decreased for the salty (r 1/4 ??0.827 and r 1/4 ??0.884, P 1/4 0.084 and P 1/4 0.047, respectively) and bitter tastes (r 1/4 ??0.990 and r 1/4 ??0.962, P 1/4 0.009 and P 1/4 0.001, respectively). For the sour taste, the hedonic scores remained stable with the increase of the stimulus in noncancer controls (r 1/4 ??0.785, P 1/4 0.115) and decreased in cancer patients (r 1/4 ??0.996, P 1/4 0.0001). The hedonic scores for the sweet taste and the bitter taste were similar in cancer patients and healthy subjects, and these scores were significantly higher in cancer patients than in healthy subjects for most of the concentrations of the salty taste and all the concentrations of the sour taste. The present study suggests that cancer patients, compared to healthy individuals, have a normal sensitivity, a normal likingfor pleasant stimuli, and a decreased dislike for unpleasant stimuli. Moreover, when compared to controls, they show higher hedonic scores for middle and high concentrations of the salty taste and for all concentrations of the sour taste. Further studies are needed to evaluate whether these changes observed in cancer patients translate into any alteration in dietary behavior and/or food preferences
The Kormendy relation of early-type galaxies as a function of wavelength in Abell S1063, MACS J0416.1-2403 and MACS J1149.5+2223
The wavelength dependence of the Kormendy relation (KR) is well characterised
at low-redshift, but poorly studied at intermediate redshifts. The KR provides
information on the evolution of the population of early-type galaxies (ETGs),
therefore, by studying it, we may shed light on the assembly processes of these
objects and their size evolution. Since studies at different redshifts are
generally conducted in different rest-frame wavebands, investigating whether
there is a wavelength dependence of the KR is fundamental to interpret the
conclusions we might draw from it. We analyse the KRs of the three Hubble
Frontier Fields clusters, Abell S1063 (z = 0.348), MACS J0416.1-2403 (z =
0.396), and MACS J1149.5+2223 (z = 0.542), as a function of wavelength. This is
the first time the KR of ETGs has been explored consistently in such a large
range of wavelength at intermediate redshifts. We exploit very deep HST
photometry, ranging from the observed B-band to the H-band, and VLT/MUSE
integral field spectroscopy. We improve the structural parameters estimation we
performed in a previous work (Tortorelli et al. 2018) by means of a newly
developed Python package called morphofit (Tortorelli&Mercurio 2023). With its
use on cluster ETGs, we find that the KR slopes smoothly increase with
wavelength from the optical to the near-infrared bands in all three clusters,
with the intercepts getting fainter at lower redshifts due to the passivisation
of the ETGs population. The slope trend is consistent with previous findings at
lower redshifts. The slope increase with wavelength implies that smaller size
ETGs are more centrally concentrated than larger size ETGs in the near-infrared
with respect to the optical regime. Since different bands probe different
stellar populations in galaxies, the slope increase also implies that smaller
ETGs have stronger internal gradients with respect to larger ETGs.Comment: Submitted to Astronomy and Astrophysics in the form of letter to the
Editor, 5 pages, 1 figure, 1 tabl
Searching for galaxy-scale strong-lenses in galaxy clusters with deep networks -- I: methodology and network performance
Galaxy-scale strong lenses in galaxy clusters provide a unique tool to
investigate their inner mass distribution and the sub-halo density profiles in
the low-mass regime, which can be compared with the predictions from
cosmological simulations. We search for galaxy-galaxy strong-lensing systems in
HST multi-band imaging of galaxy cluster cores from the CLASH and HFF programs
by exploring the classification capabilities of deep learning techniques.
Convolutional neural networks are trained utilising highly-realistic
simulations of galaxy-scale strong lenses injected into the HST cluster fields
around cluster members. To this aim, we take advantage of extensive
spectroscopic information on member galaxies in 16 clusters and the accurate
knowledge of the deflection fields in half of these from high-precision strong
lensing models. Using observationally-based distributions, we sample
magnitudes, redshifts and sizes of the background galaxy population. By placing
these sources within the secondary caustics associated with cluster galaxies,
we build a sample of ~3000 galaxy-galaxy strong lenses which preserve the full
complexity of real multi-colour data and produce a wide diversity of strong
lensing configurations. We study two deep learning networks processing a large
sample of image cutouts in three HST/ACS bands, and we quantify their
classification performance using several standard metrics. We find that both
networks achieve a very good trade-off between purity and completeness
(85%-95%), as well as good stability with fluctuations within 2%-4%. We
characterise the limited number of false negatives and false positives in terms
of the physical properties of the background sources and cluster members. We
also demonstrate the neural networks' high degree of generalisation by applying
our method to HST observations of 12 clusters with previously known
galaxy-scale lensing systems.Comment: 17 pages, 13 figures, to be published on A&
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Development of Improved Iron-Aluminide Filter Tubes and Elements
The purpose of this Cooperative Research and Development Agreement (CRADA) was to explore and develop advanced manufacturing techniques to fabricate sintered iron-aluminide intermetallic porous bodies used for gas filtration so as to reduce production costs while maintaining or improving performance in advanced coal gasification and combustion systems. The use of a power turbine fired with coal-derived synthesis gas requires some form of gas cleaning in order to protect turbine and downstream components from degradation by erosion, corrosion, and/or deposition. Hot-gas filtration is one form of cleaning that offers the ability to remove particles from the gases produced by gasification processes without having to substantially cool and, possibly, reheat them before their introduction into the turbine. This technology depends critically on materials durability and reliability, which have been the subject of study for a number of years
High-Throughput Immunoassay for the Biochemical Diagnosis of Friedreich Ataxia in Dried Blood Spots and Whole Blood
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High Temperature Corrosion Behavior of Iron Aluminide Alloys and Coatings
A multi-year effort has been focused on optimizing the long-term oxidation performance of ingot-processed (IP) and oxide-dispersion strengthened (ODS) Fe{sub 3}Al and iron aluminide-based coatings. Based on results from several composition iterations, a Hf-doped alloy (Fe-28Al-2Cr-0.05at.%Hf) has been developed with significantly better high temperature oxidation resistance than other iron aluminides. The scale adhesion is not significantly better; however, the {alpha}-Al{sub 2}O{sub 3} scale grows at a slower rate, approximately a factor of 10 less than undoped iron aluminide. The benefit of Hf is greatest at 1100-1200 C. Long-term oxidation resistance of commercially fabricated ODS Fe{sub 3}Al has been determined and compared to commercially available ODS FeCrAl. Scale spallation rates for ODS Fe{sub 3}Al are higher than for ODS FeCrAl. To complement studies of iron-aluminide weld-overlay coatings, carbon steel was coated with Fe-Al-Cr by thermal spraying. These specimens were then exposed in air at 900 and 1000 C and in air-1%SO{sub 2} at 800 C. Most likely due to an inadequate aluminum concentration in the coatings, continuous protective Al{sub 2}O{sub 3} could not be maintained and, consequently, the corrosion performance was significantly worse than what is normally observed for Fe{sub 3}Al
CLASH-VLT: Abell S1063: Cluster assembly history and spectroscopic catalogue
Context. The processes responsible for galaxy evolution in different environments as a function of galaxy mass remain heavily debated. Rich galaxy clusters are ideal laboratories in which to distinguish the role of environmental versus mass quenching because they consist of a full range of galaxies and environments. Aims. Using the CLASH-VLT survey, we assembled an unprecedentedly large sample of 1234 spectroscopically confirmed members in Abell S1063. We found a dynamically complex structure at «zcl»= 0.3457 with a velocity dispersion σv = 1380-32+26 km s-1. We investigated cluster environmental and dynamical effects by analysing the projected phase-space diagram and the orbits as a function of galaxy spectral properties. Methods. We classified cluster galaxies according to the presence and strength of the [OII] emission line, the strength of the Hδ absorption line, and colours. We investigated the relation between the spectral classes of galaxies and their position in the projected phase-space diagram. We separately analysed red and blue galaxy orbits. By correlating the observed positions and velocities with the projected phase-space constructed from simulations, we constrained the accretion redshift of galaxies with different spectral types. Results. Passive galaxies are mainly located in the virialised region, while emission-line galaxies lie beyond r200 and are accreted into the cluster at a later time. Emission-line and post-starburst galaxies show an asymmetric distribution in projected phase-space within r200; emission-line galaxies are prominent at Δv/σ ≲ -1.5 and post-starburst galaxies at Δv/σ ≲ 1.5, suggesting that backsplash galaxies lie at high positive velocities. We find that low-mass passive galaxies are accreted into the cluster before high-mass galaxies. This suggests that we observe as passives only the low-mass galaxies that are accreted early into the cluster as blue galaxies. They had the time to quench their star formation. We also find that red galaxies move on more radial orbits than blue galaxies. This can be explained if infalling galaxies can remain blue by moving on tangential orbits
Moonlighting Newborn Screening Markers: The Incidental Discovery of a Second-Tier Test for Pompe Disease
Purpose: To describe a novel biochemical marker in dried blood spots suitable to improve the specificity of newborn screening for Pompe disease.
Methods: The new marker is a ratio calculated between the creatine/creatinine (Cre/Crn) ratio as the numerator and the activity of acid α-glucosidase (GAA) as the denominator. Using Collaborative Laboratory Integrated Reports (CLIR), the new marker was incorporated in a dual scatter plot that can achieve almost complete segregation between Pompe disease and false-positive cases.
Results: The (Cre/Crn)/GAA ratio was measured in residual dried blood spots of five Pompe cases and was found to be elevated (range 4.41–13.26; 99%ile of neonatal controls: 1.10). Verification was by analysis of 39 blinded specimens that included 10 controls, 24 samples with a definitive classification (16 Pompe, 8 false positives), and 5 with genotypes of uncertain significance. The CLIR tool showed 100% concordance of classification for the 24 known cases. Of the remaining five cases, three p.V222M homozygotes, a benign variant, were classified by CLIR as false positives; two with genotypes of unknown significance, one likely informative, were categorized as Pompe disease.
Conclusion: The CLIR tool inclusive of the new ratio could have prevented at least 12 of 13 (92%) false-positive outcomes
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