The pT-differential cross section of ω meson production in pp collisions at $$ \sqrt{s} $$ = 13 TeV at midrapidity (|y| < 0.5) was measured with the ALICE detector at the LHC, covering an unprecedented transve...
The pT-differential cross section of ω meson production in pp collisions at $$ \sqrt{s} $$ = 13 TeV at midrapidity (|y| < 0.5) was measured with the ALICE detector at the LHC, covering an unprecedented transverse-momentum range of 1.6 < pT < 50 GeV/c. The meson is reconstructed via the ω → π+π−π0 decay channel. The results are compared with various theoretical calculations: PYTHIA8.2 with the Monash 2013 tune overestimates the data by up to 50%, whereas good agreement is observed with Next-to-Leading Order (NLO) calculations incorporating ω fragmentation using a broken SU(3) model. The ω/π0 ratio is presented and compared with theoretical calculations and the available measurements at lower collision energies. The presented data triples the pT ranges of previously available measurements. A constant ratio of Cω/π0 = 0.578 ± 0.006 (stat.) ± 0.013 (syst.) is found above a transverse momentum of 4 GeV/c, which is in agreement with previous findings at lower collision energies within the systematic and statistical uncertainties.
Flat spectrum radio quasars (FSRQs) constitute a class of jetted active galaxies characterized by a very luminous accretion disk, prominent and rapidly moving line-emitting cloud structures (Broad Line Region, BLR), a...
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Context. Blazars exhibit strong variability across the entire electromagnetic spectrum, including periods of high-flux states commonly dubbed as flares. The physical mechanisms in blazar jets responsible for flares re...
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Context. Blazars exhibit strong variability across the entire electromagnetic spectrum, including periods of high-flux states commonly dubbed as flares. The physical mechanisms in blazar jets responsible for flares remain to date poorly understood. Aims. We aim to better understand the emission mechanisms during blazar flares using X-ray polarimetry and broadband observations from the archetypical TeV blazar Mrk 421, which can be studied with higher accuracy than other blazars that are dimmer and/or located farther away. Methods. We study a flaring activity from December 2023 that was characterized from radio to very-high-energy (VHE;E > 0.1 TeV) gamma rays with MAGIC, Fermi-LAT, Swift, XMM-Newton and several optical and radio telescopes. These observations included, for the first time for a gamma-ray flare of a blazar, simultaneous X-ray polarization measurements with IXPE, besides optical and radio polarimetry data. We quantify the variability and correlations among the multi-band flux and polarization measurements, and describe the varying broadband emission within a theoretical scenario constrained by the polarization data. Results. We find substantial variability in both X-rays and VHE gamma rays throughout the campaign, with the highest VHE flux above 0.2 TeV occurring during the IXPE observing window, and exceeding twice the flux of the Crab Nebula. However, the VHE and X-ray spectra are on average softer, and the correlation between these two bands weaker that those reported in previous flares of Mrk 421. IXPE reveals an X-ray polarization degree significantly higher than that at radio and optical frequencies, similar to previous results on Mrk 421 and other high-synchrotron-peaked blazars. Differently to past observations, the X-ray polarization angle varies by ∼100◦ on timescales of days, and the polarization degree changes by more than a factor 4. The highest X-ray polarization degree, analyzed in 12 hrs time intervals, reaches 26 ± 2%, around which an X-
The translation of AI-generated brain metastases (BM) segmentation into clinical practice relies heavily on diverse, high-quality annotated medical imaging datasets. The BraTS-METS 2023 challenge has gained momentum f...
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The translation of AI-generated brain metastases (BM) segmentation into clinical practice relies heavily on diverse, high-quality annotated medical imaging datasets. The BraTS-METS 2023 challenge has gained momentum for testing and benchmarking algorithms using rigorously annotated internationally compiled real-world datasets. This study presents the results of the segmentation challenge and characterizes the challenging cases that impacted the performance of the winning algorithms. Untreated brain metastases on standard anatomic MRI sequences (T1, T2, FLAIR, T1PG) from eight contributed international datasets were annotated in stepwise method: published UNET algorithms, student, neuroradiologist, final approver neuroradiologist. Segmentations were ranked based on lesion-wise Dice and Hausdorff distance (HD95) scores. False positives (FP) and false negatives (FN) were rigorously penalized, receiving a score of 0 for Dice and a fixed penalty of 374 for HD95. The mean scores for the teams were calculated. Eight datasets comprising 1303 studies were annotated, with 402 studies (3076 lesions) released on Synapse as publicly available datasets to challenge competitors. Additionally, 31 studies (139 lesions) were held out for validation, and 59 studies (218 lesions) were used for testing. Segmentation accuracy was measured as rank across subjects, with the winning team achieving a LesionWise mean score of 7.9. The Dice score for the winning team was 0.65 ± 0.25. Common errors among the leading teams included false negatives for small lesions and misregistration of masks in space. The Dice scores and lesion detection rates of all algorithms diminished with decreasing tumor size, particularly for tumors smaller than 100 mm3. In conclusion, algorithms for BM segmentation require further refinement to balance high sensitivity in lesion detection with the minimization of false positives and negatives. The BraTS-METS 2023 challenge successfully curated well-annotated, diverse d
Aims. Mrk 421 was in its most active state around early 2010, which led to the highest TeV gamma-ray flux ever recorded from any active galactic nuclei (AGN). We aim to characterize the multiwavelength behavior during...
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Aims. Mrk 421 was in its most active state around early 2010, which led to the highest TeV gamma-ray flux ever recorded from any active galactic nuclei (AGN). We aim to characterize the multiwavelength behavior during this exceptional year for Mrk 421, and evaluate whether it is consistent with the picture derived with data from other less exceptional years. Methods. We investigated the period from November 5, 2009, (MJD 55140) until July 3, 2010, (MJD 55380) with extensive coverage from very-high-energy (VHE;E > 100 GeV) gamma rays to radio with MAGIC, VERITAS, Fermi-LAT, RXTE, Swift, GASP-WEBT, VLBA, and a variety of additional optical and radio telescopes. We characterized the variability by deriving fractional variabilities as well as power spectral densities (PSDs). In addition, we investigated images of the jet taken with VLBA and the correlation behavior among different energy bands. Results. Mrk 421 was in widely different states of activity throughout the campaign, ranging from a low-emission state to its highest VHE flux ever recorded. We find the strongest variability in X-rays and VHE gamma rays, and PSDs compatible with power-law functions with indices around 1.5. We observe strong correlations between X-rays and VHE gamma rays at zero time lag with varying characteristics depending on the exact energy band. We also report a marginally significant (∼ 3σ) positive correlation between high-energy (HE;E > 100 MeV) gamma rays and the ultraviolet band. We detected marginally significant (∼ 3σ) correlations between the HE and VHE gamma rays, and between HE gamma rays and the X-ray, that disappear when the large flare in February 2010 is excluded from the correlation study, hence indicating the exceptionality of this flaring event in comparison with the rest of the campaign. The 2010 violent activity of Mrk421 also yielded the first ejection of features in the VLBA images of the jet of Mrk 421. Yet the large uncertainties in the ejection times of these unprece
OBJECTIVE:Many epithelial ovarian cancer (EOC) risk factors relate to sex hormones. The association between these factors and the expression of androgen receptor (AR), estrogen receptor-α (ER), and progesterone recep...
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OBJECTIVE:Many epithelial ovarian cancer (EOC) risk factors relate to sex hormones. The association between these factors and the expression of androgen receptor (AR), estrogen receptor-α (ER), and progesterone receptor (PR) in tumors is unknown.
METHOD:We linked epidemiologic, AR/ER/PR tumor expression, and survival data from 19 studies in the Ovarian Cancer Association Consortium (OCAC; 4762 cases, 20,888 controls) and the Ovarian Tumor Tissue Analysis (OTTA) consortium (5737 cases). We estimated odds ratios (ORs) and 95 % confidence intervals (CIs) between hormonally-linked factors and tumor AR/ER/PR expression using polytomous logistic regression. We assessed survival by AR/ER/PR tumor expression overall and by histotype using Kaplan-Meier curves and Cox proportional hazards models.
RESULTS:Overweight/obesity was associated with higher risk of ER- tumors (OR:1.53, 95 % I:1.18-1.98). Hysterectomy was associated with greater risk of ER+ tumors (OR:4.99, 95 % CI:4.27-5.83), which varied by AR expression (P0.003). Postmenopause was associated with a higher risk of PR- tumors (OR 1.52, 95 % CI 1.26-1.83), which varied based by AR (P < 0.001) and ER (P < 0.001) expression. Gravidity, oral contraception duration, and breastfeeding duration showed differing dose-response relationships according to AR/ER/PR expression. Hormone therapy use, postmenopause, physical inactivity, and being obese/overweight prior to diagnosis were differentially associated with survival based on AR/ER/PR expression and histotype.
CONCLUSION:EOC has varying risk and prognostic profiles depending on both histotype and AR/ER/PR expression. Biological mechanisms underlying the association between hormonally-linked factors and EOC need to be studied by both histotypes and by AR, ER, and PR expression.
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