93 research outputs found
Unconditional adoption rules out the need for parent–offspring recognition in a single‐brooded colonial seabird
Parent–offspring
recognition (POR) is fundamental in colonial birds when the potential
intermingling of chicks is higher due to the large number and proximity of nests.
In species with isolated nests, where chick presence in the nest is strong contextual
evidence of kinship, there might be circumstances when the parent might doubt the
identity of the chick, but not enough to reject it. Olfactory-based
recognition of conspecifics
and nest sites in birds has gained strong evidence suggesting a potential role
of olfaction in POR. Despite that, there are no studies testing it. We used Scopoli's
shearwater (Calonectris diomedea) as model colonial single-brooded
species with a developed
olfactory sense, usually breeding in well-spaced
nests with low probability of
chicks mixing. We tested the parent's ability to selectively respond to their own chick
as opposed to a simpler rule of feeding any chick found in the nest by means of chick-fostering
experiments. We designed two cross-fostering
experiments using chicks of
different ages to test whether the ability of parents to recognize a related chick develops
over time, possibly after acquiring an own distinctive odour. Finally, we also manipulated
nests’ odour to disentangle the confounding effect of nest site recognition
from POR when parents return at night. All experimental chicks were adopted by parents
as the weight and bill growth of cross-fostered
chicks did not differ significantly
from the control group. We recorded a small difference in weight when foster chicks
were inside an odour-manipulated
nest; although we did not record weight loss in
experimental chicks, only a steeper increase in weight was observed in control chicks.
In conclusion, adoption in Scopoli's shearwater seems to follow the rule "if the young is
in my nest, accept it" proposed by Beecher (1991) for species with spatially separated
nests and low chick mobility.Fundação para a Ciência e Tecnologia - FCTinfo:eu-repo/semantics/acceptedVersio
Safety of meglumine gadoterate (Gd-DOTA)-enhanced MRI compared to unenhanced MRI in patients with chronic kidney disease (RESCUE study)
OBJECTIVE: To prospectively compare the renal safety of meglumine gadoterate (Gd-DOTA)-enhanced magnetic resonance imaging (MRI) to a control group (unenhanced MRI) in high-risk patients. METHODS: Patients with chronic kidney disease (CKD) scheduled for MRI procedures were screened. The primary endpoint was the percentage of patients with an elevation of serum creatinine levels, measured 72 ± 24 h after the MRI procedure, by at least 25 % or 44.2 μmol/l (0.5 mg/dl) from baseline. A non-inferiority margin of the between-group difference was set at −15 % for statistical analysis of the primary endpoint. Main secondary endpoints were the variation in serum creatinine and eGFR values between baseline and 72 ± 24 h after MRI and the percentage of patients with a decrease in eGFR of at least 25 % from baseline. Patients were screened for signs of nephrogenic systemic fibrosis (NSF) at 3-month follow-up. RESULTS: Among the 114 evaluable patients, one (1.4 %) in the Gd-DOTA-MRI group and none in the control group met the criteria of the primary endpoint [Δ = −1.4 %, 95%CI = (−7.9 %; 6.7 %)]. Non-inferiority was therefore demonstrated (P = 0.001). No clinically significant differences were observed between groups for the secondary endpoints. No serious safety events (including NSF) were noted. CONCLUSION: Meglumine gadoterate did not affect renal function and was a safe contrast agent in patients with CKD. KEY POINTS: • Contrast-induced nephropathy (CIN) is a potential problem following gadolinium administration for MRI. • Meglumine gadoterate (Gd-DOTA) appears safe, even in patients with chronic kidney disease. • Gd-DOTA only caused a temporary creatinine level increase in 1/70 such patients. • No case or sign of NSF was detected at 3-month follow-up
An Explainable AI System for Automated COVID-19 Assessment and Lesion Categorization from CT-scans
COVID-19 infection caused by SARS-CoV-2 pathogen is a catastrophic pandemic
outbreak all over the world with exponential increasing of confirmed cases and,
unfortunately, deaths. In this work we propose an AI-powered pipeline, based on
the deep-learning paradigm, for automated COVID-19 detection and lesion
categorization from CT scans. We first propose a new segmentation module aimed
at identifying automatically lung parenchyma and lobes. Next, we combined such
segmentation network with classification networks for COVID-19 identification
and lesion categorization. We compare the obtained classification results with
those obtained by three expert radiologists on a dataset consisting of 162 CT
scans. Results showed a sensitivity of 90\% and a specificity of 93.5% for
COVID-19 detection, outperforming those yielded by the expert radiologists, and
an average lesion categorization accuracy of over 84%. Results also show that a
significant role is played by prior lung and lobe segmentation that allowed us
to enhance performance by over 20 percent points. The interpretation of the
trained AI models, moreover, reveals that the most significant areas for
supporting the decision on COVID-19 identification are consistent with the
lesions clinically associated to the virus, i.e., crazy paving, consolidation
and ground glass. This means that the artificial models are able to
discriminate a positive patient from a negative one (both controls and patients
with interstitial pneumonia tested negative to COVID) by evaluating the
presence of those lesions into CT scans. Finally, the AI models are integrated
into a user-friendly GUI to support AI explainability for radiologists, which
is publicly available at http://perceivelab.com/covid-ai
Le Soprintendenze bibliografiche dello Stato
The intervention sums up the story of the bibliographic Superintendences, ministerial offices funded in 1919 and transferred to the Regions in 1972, and talks about their positioning within the history of the cultural policies from the Italian unification onwards. Sources used have been legislative and regulatory acts, essays on the subject from different periods and written testimonies of sector's operators. The immediate reason for this has been the need to study the development of state and regional policies on this matter when reform interventions deeply modify the balance of the last forty years. The survey has outlined also the persistence of never-solved problems in the planning of public interventions: for example, different functions have been managed by eclectic structures and at the same time the performance of the single functions has been fragmented based on their own institutions
Endothelial Cells Obtained from Patients Affected by Chronic Venous Disease Exhibit a Pro-Inflammatory Phenotype
The inflammatory properties of vein endothelium in relation to chronic venous disease (CVD) have been poorly investigated. Therefore, new insights on the characteristics of large vein endothelium would increase our knowledge of large vessel physiopathology.
METHODOLOGY/PRINCIPAL FINDINGS:
Surgical specimens of veins were obtained from the tertiary venous network (R3) and/or saphenous vein (SF) of patients affected by CVD and from control individuals. Highly purified venous endothelial cell (VEC) cultures obtained from CVD patients were characterized for morphological, phenotypic and functional properties compared to control VEC. An increase of CD31/PECAM-1, CD146 and ICAM-1 surface levels was documented at flow cytometry in pathological VEC with respect to normal controls. Of note, the strongest expression of these pro-inflammatory markers was observed in VEC obtained from patients with more advanced disease. Similarly, spontaneous cell proliferation and resistance to starvation was higher in pathological than in normal VEC, while the migratory response of VEC showed an opposite trend, being significantly lower in VEC obtained from pathological specimens. In addition, in keeping with a higher baseline transcriptional activity of NF-kB, the release of the pro-inflammatory cytokines osteoprotegerin (OPG) and vascular endothelial growth factor (VEGF) was higher in pathological VEC cultures with respect to control VEC. Interestingly, there was a systemic correlation to these in vitro data, as demonstrated by higher serum OPG and VEGF levels in CVD patients with respect to normal healthy controls.
CONCLUSION/SIGNIFICANCE:
Taken together, these data indicate that large vein endothelial cells obtained from CVD patients exhibit a pro-inflammatory phenotype, which might significantly contribute to systemic inflammation in CVD patients
A Major Role for Side-Chain Polyglutamine Hydrogen Bonding in Irreversible Ataxin-3 Aggregation
The protein ataxin-3 consists of an N-terminal globular Josephin domain (JD) and an unstructured C-terminal region containing a stretch of consecutive glutamines that triggers the neurodegenerative disorder spinocerebellar ataxia type 3, when it is expanded beyond a critical threshold. The disease results from misfolding and aggregation, although the pathway and structure of the aggregation intermediates are not fully understood. In order to provide insight into the mechanism of the process, we monitored the aggregation of a normal (AT3Q24) ataxin-3, an expanded (AT3Q55) ataxin-3, and the JD in isolation. We observed that all of them aggregated, although the latter did so at a much slower rate. Furthermore, the expanded AT3Q55 displayed a substantially different behavior with respect to the two other variants in that at the latest stages of the process it was the only one that did the following: i) lost its reactivity towards an anti-oligomer antibody, ii) generated SDS-insoluble aggregates, iii) gave rise to bundles of elongated fibrils, and iv) displayed two additional bands at 1604 and 1656 cm−1 in FTIR spectroscopy. Although these were previously observed in other aggregated polyglutamine proteins, no one has assigned them unambiguously, yet. By H/D exchange experiments we show for the first time that they can be ascribed to glutamine side-chain hydrogen bonding, which is therefore the hallmark of irreversibly SDS-insoluble aggregated protein. FTIR spectra also showed that main-chain intermolecular hydrogen bonding preceded that of glutamine side-chains, which suggests that the former favors the latter by reorganizing backbone geometry
Latent analysis of unmodified biomolecules and their complexes in solution with attomole detection sensitivity
The study of biomolecular interactions is central to an understanding of function, malfunction and therapeutic modulation of biological systems, yet often involves a compromise between sensitivity and accuracy. Many conventional analytical steps and the procedures required to facilitate sensitive detection, such as the incorporation of chemical labels, are prone to perturb the complexes under observation. Here we present a 'latent' analysis approach that uses chemical and microfluidic tools to reveal, through highly sensitive detection of a labelled system, the behaviour of the physiologically relevant unlabelled system. We implement this strategy in a native microfluidic diffusional sizing platform, allowing us to achieve detection sensitivity at the attomole level, determine the hydrodynamic radii of biomolecules that vary by over three orders of magnitude in molecular weight, and study heterogeneous mixtures. We illustrate these key advantages by characterizing a complex of an antibody domain in the solution phase and under physiologically relevant conditions.We would like to thank the ERC, BBSRC, Wellcome Trust, Newman Foundation, Winston Churchill Foundation, and Elan Pharmaceuticals for financial support. E.D.G was supported by the MRC (G1002272)
Extraosseus Ewing sarcoma: An uncommon periclavicular location
A rapidly enlarging right sternoclavicular mass in a young male was labeled as a nonspecific mass. MRI played a crucial role in characterizing the lesion, helping to define the possible mesenchymal origin and the relative involvement of the surrounding structures. We also discuss the differential diagnosis of an extraosseus Ewing sarcoma (ES), with its imaging findings
Monte Carlo importance sampling optimization for system reliability applications
This paper focuses on the reliability analysis of multicomponent systems by the importance sampling technique, and, in particular, it tackles the optimization aspect. A methodology based on the minimization of the variance at the component level is proposed for the class of systems consisting of independent components. The claim is that, by means of such a methodology, the optimal biasing could be achieved without resorting to the typical approach by trials
Citizen science data reveal possible multi-decadal phenological changes in the arrival time of a migratory tropical seabird species at the breeding ground
· Changes in climate and weather variability are having global impacts on the lives of organisms, particularly on upper
trophic-level predators such as pelagic seabirds. In the North Atlantic, migratory seabirds are expected to respond to climate
variability by adjusting their seasonal events, including the timing of migration and arrival at the breeding site. The timing
of these events may be infuenced by large-scale atmospheric phenomena such as the North Atlantic Oscillation (NAO) and
the Atlantic Multi-decadal Oscillation (AMO) that gauge temporal and spatial variation in environmental conditions across
the North Atlantic. In the Bermuda Islands (32° 17′ 58″ N, 64° 47′ 25″ W), the White-tailed tropicbird (Phaethon lepturus
catsbyii) is one of the few breeding seabird species which returns every year between February and March after migration.
According to local belief their return announces the arrival of Spring, and this cultural importance means that the event is
noticed. Only recently, early tropicbird returns have been recorded and associated with unusual climate/weather conditions
experienced across the region. This raised the question of whether the species is showing some change in its phenology and
whether it might be afected by changing climatic conditions. To answer this question, we investigated tropicbird arrival dates
at Bermuda using current and historic observation data retrieved from the eBird citizen science platform. After accounting for
biases inherent to opportunistic data collection, we selected and used the frst annual observation as a proxy for bird arrival
time at the Bermuda breeding ground from 1953 to 2023. We found that tropicbird observation dates advanced substantially
over the past 70 years suggesting that arrival time has been likely shifting of ca. 20–25 days. However, frst observation
dates were not related to the variation in annual or winter NAO and AMO Indices, and further investigation is required to
understand the underlying causes of these progressively early arrivals. Overall, the study highlights that citizen-science data
can be used to unveil hidden phonological patterns when a standardized long-term data collection is missing.Fundação para a Ciência e Tecnologia - FCTinfo:eu-repo/semantics/publishedVersio
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