519 research outputs found
How robust are particle physics predictions in asymptotic safety?
The framework of trans-Planckian asymptotic safety has been shown to generate
phenomenological predictions in the Standard Model and in some of its simple
new physics extensions. A heuristic approach is often adopted, which bypasses
the functional renormalization group by relying on a parametric description of
quantum gravity with universal coefficients that are eventually obtained from
low-energy observations. Within this approach, a few simplifying approximations
are typically introduced, including the computation of matter renormalization
group equations at 1~loop, an arbitrary definition of the position of the
Planck scale at GeV, and an instantaneous decoupling of gravitational
interactions below the Planck scale. In this work we systematically
investigate, both analytically and numerically, the impact of dropping each of
those approximations on the predictions for certain particle physics scenarios.
In particular we study two extensions of the Standard Model, the gauged
model and the leptoquark model, for which we determine a set of
irrelevant gauge and Yukawa couplings. In each model, we present numerical and
analytical estimates of the uncertainties associated with the predictions from
asymptotic safety.Comment: 35 pages, 6 figures, 2 table
Androgen receptor polymorphisms and testicular cancer risk
Testicular cancer (TC) is currently the most common malignant solid tumour in Caucasian males aged 15-39 years. Epidemiological evidence suggests that its onset may be due to an imbalance in the action of steroidal sex hormones and their receptors. A faulty androgen receptor signalling pathway can, in fact, cause various male reproductive disorders. The androgen receptor (AR) gene has two polymorphic segments consisting of CAG and GGC repeats. The length of CAG repeats has been shown to affect the regulation of AR activity. In our study, we used fragment analysis to evaluate the AR gene repeats of 302 TC patients and 322 controls, to establish if there is any association between repeat number and TC. This study of the largest Italian caseload investigated to date highlighted three particularly significant aspects. First, a CAG repeat number of ≥25 may be considered a risk factor for the onset of TC, given its greater frequency in patients in comparison with controls. This difference became significant for the non-seminoma group. Second, men with CAG repeats below 21 or above 24 were found to have a, respectively, 50 and 76% higher risk of TC than those with CAG 21-24, suggesting that these too can be considered a risk factor for TC. Finally, stage II patients were more likely to have a CAG repeat number 24 than stage I patients. © 2014 American Society of Andrology and European Academy of Andrology
Energy dispersive x-ray spectroscopy for nanostructured thin film density evaluation
In this paper, we report on two fast and non-destructive methods for nanostructured film density evaluation based on a combination of energy dispersive x-ray spectroscopy for areal density measurement and scanning electron microscopy (SEM) for thickness evaluation. These techniques have been applied to films with density ranging from the density of a solid down to a few mg cm(-3), with different compositions and morphologies. The high resolution of an electron microprobe has been exploited to characterize non-uniform films both at the macroscopic scale and at the microscopic scale
Global analysis and LHC study of a vector-like extension of the Standard Model with extra scalars
We perform a global analysis of a vector-like extension of the Standard
Model, which also features additional doublet and singlet scalars. The usual
Yukawa interactions are forbidden in this setup by an extra U(1) global
symmetry and the masses of the second and third family quarks and leptons are
generated via the mixing with the vector-like sector. We identify three
best-fit benchmark scenarios which satisfy the constraints imposed by the
stability of the scalar potential, the perturbativity of the coupling
constants, the measurement of the muon anomalous magnetic moment and the
non-observation of the flavor violating tau decays. We show that dominant
contributions to the muon originate in this model from the charged
Higgs/neutral lepton one-loop diagrams, thus correcting an inaccurate statement
than can be found in the literature. We also perform a detailed LHC analysis of
the benchmark scenarios. We investigate the experimental constraints stemming
from direct searches for vector-like quarks, vector-like leptons and exotic
scalars. While we show that the model is not currently tested by any collider
experiment, we point out that decays of a heavy Higgs boson into two tau
leptons may offer a smoking gun signature for the model verification in
upcoming runs at the LHC.Comment: 42 pages, 12 tables, 9 figure
Constraints on solutions to the flavor anomalies with trans-Planckian asymptotic safety
Motivated by the flavor anomalies in transitions, we embed minimal
models with a gauge boson, vector-like fermions, and a singlet scalar in
the framework of trans-Planckian asymptotic safety. The presence of a fixed
point in the renormalization group flow of the models' parameters leads to
predictions for the kinetic mixing, the New Physics Yukawa
couplings, and the quartic couplings of the scalar potential. We derive the
constraint on the kinetic mixing from the most recent high-mass dilepton
resonance searches at the LHC, showing that this bound is often inescapable in
this framework, unless the U(1) charges conspire to forbid the radiative
generation of kinetic mixing. In the latter case, the parameter space
consistent with the flavor anomalies can still be probed in depth by direct LHC
searches for heavy vector-like quarks and leptons. We derive the current
exclusion bounds and projections for future high-luminosity runs.Comment: 41 pages, 5 figures, 4 table
A multi-artifact EEG denoising by frequency-based deep learning
Electroencephalographic (EEG) signals are fundamental to neuroscience
research and clinical applications such as brain-computer interfaces and
neurological disorder diagnosis. These signals are typically a combination of
neurological activity and noise, originating from various sources, including
physiological artifacts like ocular and muscular movements. Under this setting,
we tackle the challenge of distinguishing neurological activity from
noise-related sources. We develop a novel EEG denoising model that operates in
the frequency domain, leveraging prior knowledge about noise spectral features
to adaptively compute optimal convolutional filters for noise separation. The
model is trained to learn an empirical relationship connecting the spectral
characteristics of noise and noisy signal to a non-linear transformation which
allows signal denoising. Performance evaluation on the EEGdenoiseNet dataset
shows that the proposed model achieves optimal results according to both
temporal and spectral metrics. The model is found to remove physiological
artifacts from input EEG data, thus achieving effective EEG denoising. Indeed,
the model performance either matches or outperforms that achieved by benchmark
models, proving to effectively remove both muscle and ocular artifacts without
the need to perform any training on the particular type of artifact.Comment: Accepted at the Italian Workshop on Artificial Intelligence for
Human-Machine Interaction (AIxHMI 2023), November 06, 2023, Rome, Ital
Breast cancer genome-wide association studies: there is strength in numbers
Breast cancer (BC) is a heterogeneous disease that exhibits familial aggregation. Family linkage studies have identified high-penetrance genes, BRCA1, BRCA2, PTEN and TP53, that are responsible for inherited BC syndromes. Moreover, a combination of family-based and population-based approaches indicated that genes involved in DNA repair, such as CHEK2, ATM, BRIP and PALB2, are associated with moderate risk. Therefore, all of these known genes account for only 25% of the familial aggregation cases. Recently, genome wide association studies (GWAS) in BC revealed single nucleotide polymorphisms (SNPs) in five novel genes associated to susceptibility: TNRC9, FGFR2, MAP3K1, H19 and lymphocyte-specific protein 1 (LSP1). The most strongly associated SNP was in intron 2 of the FGFR2 gene that is amplified and overexpressed in 5-10% of BC. rs3803662 of TNRC9 gene has been shown to be the SNP with the strongest association with BC, in particular, this polymorphism seems to be correlated with bone metastases and estrogen receptor positivity. Relevant data indicate that SNP rs889312 in MAP3K1 is correlated with BC susceptibility only in BRCA2 mutation carriers, but is not associated with an increased risk in BRCA1 carriers. Finally, different SNPs in LSP1 and H19 and in minor genes probably were associated with BC risk. New susceptibility allelic variants associated with BC risk were recently discovered including potential causative genes involved in regulation of cell cycle, apoptosis, metabolism and mitochondrial functions. In conclusion, the identification of disease susceptibility loci may lead to a better understanding of the biological mechanism for BC to improve prevention, early detection and treatment
Cisto dentÃgero: revisão e apresentação de um caso de localização incomum
Revisão Bibliográfica sobre a etiopatogenia, distribuição, incidência e evolução do cisto dentÃgero, incluindo a apresentação de um caso de ocorrência ectópica do 3° molar inferior em área de apófise coronóide esquerda, em paciente feminina de 44 ano
The Rapid Identification of Anoplophora chinensis (Coleoptera: Cerambycidae) From Adult, Larval, and Frass Samples Using TaqMan Probe Assay
A molecular diagnostic method using TaqMan probe qPCR is presented for the identification of Anoplophora chinensis (Förster) (Coleoptera: Cerambycidae) from whole body insects (adults and larvae) and frass samples stored under different conditions. The results showed a perfect amplification of DNA from all samples; the repeatability and reproducibility of the protocol were very good, with standard deviations of inter-run and intrarun variability less than or equal to 0.5. The assay allowed to discern all A. chinensis samples from those of the other non-target wood-borer species, with 100% correspondence to the homologous sequences. No amplification or cross reactions were observed with A. glabripennis (Motschulsky) (Coleoptera: Cerambycidae), which is the most related species among those tested. The protocol was validated by an internal blind panel test which showed a good correspondence between the results obtained by different operators in the same lab. The analytical sensitivity for the lab frass with the Probe qPCR, namely the lowest amount of A. chinensis DNA that can be detected (LoD), was 0.64 pg/μl with a Cq of 34.87. The use of indirect evidence for the identification of a pest is an important feature of the method, which could be crucial to detect the presence of wood-boring insects.
This diagnostic tool can help prevent the introduction of A. chinensis into new environments or delimit existing outbreak areas thanks to indirect frass diagnosis
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