161 research outputs found
Cornering the Planck tension with future CMB data
The precise measurements of Cosmic Microwave Background Anisotropy angular
power spectra made by the Planck satellite show an anomalous value for the
lensing amplitude, defined by the parameter , at more than
standard deviations. In this paper, after discussing the current status of the
anomaly, we quantify the potential of future CMB measurements in
confirming/falsifying the tension. We find that a space-based
experiment as LiteBIRD could falsify the current tension at the
level of standard deviations. Similar constraints can be achieved by a
Stage-III experiment assuming an external prior on the reionization optical
depth of as already provided by the Planck satellite. A
Stage-IV experiment could further test the tension at the level of
standard deviations. A comparison between temperature and polarization
measurements made at different frequencies could further identify possible
systematics responsible for . We show that, in the case of the
CMB-S4 experiment, polarization data alone will have the potential of
falsifying the current anomaly at more than five standard deviation
and to strongly bound its frequency dependence. We also evaluate the future
constraints on a possible scale dependence for .Comment: 5 pages, 4 figure
Diagnostic imaging and CEUS findings in a rare case of Desmoid-type fibromatosis. A case report
Desmoid-type fibromatosis (DF), also known as aggressive fibromatosis, is a locally aggressive benign fibroblastic neoplasm that can infiltrate or recur but cannot metastasize. It is rare, with an estimated annual incidence of two to four new cases per million people. Most DFs occur sporadically, but it may also be associated with the hereditary syndrome familial adenomatous polyposis. Treatment is necessary when the disease is symptomatic, especially in case of compression of critical structures. When possible, surgical resection is the treatment of choice; however, recurrence is common. Due to the high rate of recurrence, imaging plays an important role not only in diagnosis, but also in the management of DF. Although there are a number of studies describing CT and MRI findings of DF, there is no description of contrast-enhanced ultrasound findings
The cosmological impact of future constraints on from gravitational-wave standard sirens
Gravitational-wave standard sirens present a novel approach for the
determination of the Hubble constant. After the recent spectacular confirmation
of the method thanks to GW170817 and its optical counterpart, additional
standard siren measurements from future gravitational-wave sources are expected
to constrain the Hubble constant to high accuracy. At the same time, improved
constraints are expected from observations of cosmic microwave background (CMB)
polarization and from baryon acoustic oscillations (BAO) surveys. We explore
the role of future standard siren constraints on in light of expected
CMB+BAO data. Considering a -parameters cosmological model, in which
curvature, the dark energy equation of state, and the Hubble constant are
unbounded by CMB observations, we find that a combination of future CMB+BAO
data will constrain the Hubble parameter to . Further extending
the parameter space to a time-varying dark energy equation of state, we find
that future CMB+BAO constraints on are relaxed to . These
accuracies are within reach of future standard siren measurements from the
Hanford-Livingston-Virgo and the Hanford-Livingston-Virgo-Japan-India networks
of interferometers, showing the cosmological relevance of these sources. If
future gravitational-wave standard siren measurements reach on , as
expected, they would significantly improve future CMB+BAO constraints on
curvature and on the dark energy equation of state by up to a factor .
We also show that the inclusion of constraints from gravitational-wave
standard sirens could result in a reduction of the dark energy figure-of-merit
(i.e., the cosmological parameter volume) by up to a factor of .Comment: 14 pages, 5 figures, included discussion on FoM, new references, in
press on PR
Is the Harrison-Zel'dovich spectrum coming back? ACT preference for and its discordance with Planck
The Data Release 4 of the Atacama Cosmology Telescope (ACT) shows an
agreement with an Harrison-Zel'dovich primordial spectrum (), introducing a tension with a significance of CL with the
results from the Planck satellite. The discrepancy on the value of the scalar
spectral index is neither alleviated with the addition of large scale structure
information nor with the low multipole polarization data. We discuss possible
avenues to alleviate the tension relying on either neglecting polarization
measurements from ACT or in extending different sectors of the theory.Comment: 8 pages, 5 figures, 2 tables. Accepted for publication in MNRA
Sparse Vicious Attacks on Graph Neural Networks
Graph Neural Networks (GNNs) have proven to be successful in several
predictive modeling tasks for graph-structured data.
Amongst those tasks, link prediction is one of the fundamental problems for
many real-world applications, such as recommender systems.
However, GNNs are not immune to adversarial attacks, i.e., carefully crafted
malicious examples that are designed to fool the predictive model.
In this work, we focus on a specific, white-box attack to GNN-based link
prediction models, where a malicious node aims to appear in the list of
recommended nodes for a given target victim.
To achieve this goal, the attacker node may also count on the cooperation of
other existing peers that it directly controls, namely on the ability to inject
a number of ``vicious'' nodes in the network.
Specifically, all these malicious nodes can add new edges or remove existing
ones, thereby perturbing the original graph.
Thus, we propose SAVAGE, a novel framework and a method to mount this type of
link prediction attacks.
SAVAGE formulates the adversary's goal as an optimization task, striking the
balance between the effectiveness of the attack and the sparsity of malicious
resources required.
Extensive experiments conducted on real-world and synthetic datasets
demonstrate that adversarial attacks implemented through SAVAGE indeed achieve
high attack success rate yet using a small amount of vicious nodes.
Finally, despite those attacks require full knowledge of the target model, we
show that they are successfully transferable to other black-box methods for
link prediction
Phenotypic and molecular selection of a superior Solanum pennellii introgression sub-line suitable for improving quality traits of cultivated tomatoes
The Solanum pennellii Introgression Line (IL) population can be exploited to identify favorable alleles that can improve yield and fruit quality traits in commercial tomato varieties. Over the past few years, we have selected ILs that exhibit increased content of antioxidant compounds in the fruit compared to the cultivar M82, which represents the genetic background in which the different wild regions of the S. pennellii ILs were included. Recently, we have identified seven sub-lines of the IL7-3 accumulating different amounts of antioxidants in the ripe fruit. Since the wild region carried on chromosome 7
induces a low fruit production in IL7-3, the first aim of the present work was to evaluate yield performances of the selected sub-lines in three experimental fields located in the South of Italy. Another aim was to confirm in the same lines the high levels of antioxidants and evaluate other fruit quality traits. On red ripe fruit, the levels of soluble solids content, firmness, and ascorbic acid (AsA) were highly variable among the sub-lines grown in three environmental conditions, evidencing a significant genotype by environment interaction for soluble solids and AsA content. Only one sub-line (coded R182) exhibited
a significantly higher firmness, even though no differences were observed for this trait between the parental lines M82 and IL7-3. The same sub-line showed significantly higher AsA content compared to M82, thus resembling IL7-3. Even though IL7-3 always exhibited a significantly lower yield, all the sub-lines showed yield variability over the three trials. Interestingly, the sub-line R182, selected for its better performances in terms of fruit quality, in all the trials showed a production comparable to that of the control line M82. A group of species-specific molecular markers was tested on R182 and on the
parental genotypes in order to better define the wild genomic regions carried by the elite line R182. In these regions three candidate genes that could increase the level of AsA in the fruit were identified. In the future, the line R182 could be used as pre-breeding material in order to obtain new varieties improved for nutritional traits.info:eu-repo/semantics/publishedVersio
Exploiting Genetic and Genomic Resources to Enhance Heat-Tolerance in Tomatoes
High temperature is one of the most detrimental abiotic stresses in tomatoes. Many studies highlighted that even small increases in temperature can alter the plant reproductive system, causing a significant reduction in tomato yield. The aim of this study was to exploit the phenotypic and genomic variations of a tomato landrace collection grown at high temperatures. Fifteen genotypes were selected as the best performing in two experimental fields. The selection was based on six yield-related traits, including flower earliness, number of flowers per inflorescence, fruit set, number of fruit per plant, fruit weight and yield per plant. In order to identify markers targeting traits that could be highly influenced by adverse climate conditions, such as flowering and fruit setting, an association mapping approach was undertaken exploiting a tomato high-throughput genomic array. The phenotypic variability observed allowed us to identify a total of 15 common markers associated with the studied traits. In particular, the most relevant associations co-localized with genes involved in the floral structure development, such as the style2.1 gene, or with genes directly involved in the response to abiotic stresses. These promising candidate genes will be functionally validated and transferred to a cultivated tomato to improve its performance under high temperatures
Non-arthritic Hip Score: translation, cultural adaptation and validation of the Italian version
BACKGROUNDː the aim of the study was to translate the Nonarthritic Hip Score (NAHS)
questionnaire into the Italian language, to adapt it into the Italian culture and to validate it.
METHODSː Translation and cultural adaptation were performed following international
guidelines. To assess the reliability of the tool internal consistency and test-retest reliability
were evaluated through Cronbach’s alpha and Intraclass Correlation Coefficient (ICC)
respectively. Validity was evaluated by Pearson’s correlation coefficient between the NAHS,
the Lequesne Index of Severity for Osteoarthritis of the Hip (LISOH) and the Western
Ontario and McMaster Universities Arthritis Index (WOMAC), that were administered
together. These three questionnaires were applied to a population of 64 individuals between
19 and 82 years old with generic hip injures or diseases.
RESULTSː The items of the original version of NAHS are similar or equal to the items of
the Italian version of NAHS. Cronbach’s α was 0.614 (Pain); 0.821 (Symptom); 0.877
(Function); 0.896 (Activity). ICC for total score was 0.905. The correlation with the
WOMAC was 0.850 (p< 0.01) and with the LISOH was 0.738 (p<0.01).
CONCLUSIONSː The NAHS showed positive results for reliability and validity so it was
translated into Italian language and was cross-culturally adapted to Italian culture. This
questionnaire is a good instrument in clinical practice and scientific research for the
evaluation of young and active individuals affected by hip injures or diseases
Reduction of ST-elevation myocardial infarction in Canton Ticino (Switzerland) after smoking bans in enclosed public places—No Smoke Pub Study
Background: Second-hand smoke increases the risk of acute myocardial infarction. Canton Ticino (CT) first introduced a smoking ban in public places in 2007. This offered the opportunity to assess the long-term impact of a smoking ban on the incidence of ST-elevation myocardial infarctions (STEMI) compared with a population where the law was not yet implemented. Methods: We assessed the incidence of STEMI hospitalizations per 100 000 inhabitants both during 3 years before and after the ban application in CT and in Canton Basel City (CBC), where this law was not yet applied. Data were obtained from the codified hospital registry (ICD-10 codes). Results: In CT, the mean incidence of STEMI admissions during the 3 pre-ban years (123.7) was significantly higher than the incidence of admissions in each of the 3 post-ban years (92.9, 101.6 and 89.6 respectively; P <.024). Analysing population subsets, a post-ban reduction was observed among ≥65-year-old people of both sexes in each of the 3 post-ban years and in the <65-year age group during the first post-ban year (P = 0.02). Conversely, the mean incidence of STEMI hospitalizations in CBC (92.4) didn't change significantly in each of the 3 post-ban years (83.9, 83.3 and 79.5, P = NS) during the same period. However, a significant long-term reduction in STEMI admissions was observed in CBC among the male group with ≥65 years (P < 0.01). Conclusion: Our work suggests a significant impact of the smoke-free policy on the number of annual STEMI. Specific population subsets (i.e. ≥65-year-old females) were particularly affected by the smoking ban, showing a significant reduction in STEMI hospitalization
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