We propose a two-dimensional hard-core loop-gas model as a way to regularize the asymptotically free massive continuum quantum field theory that emerges at the Berezinskii-Kosterlitz-Thouless ...transition. Without fine-tuning, our model can reproduce the universal step-scaling function of the classical lattice XY model in the massive phase as we approach the phase transition. This is achieved by lowering the fugacity of Fock-vacuum sites in the loop-gas configuration space to zero in the thermodynamic limit. Some of the universal quantities at the Berezinskii-Kosterlitz-Thouless transition show smaller finite size effects in our model as compared to the traditional XY model. Our model is a prime example of qubit regularization of an asymptotically free massive quantum field theory in Euclidean space-time and helps understand how asymptotic freedom can arise as a relevant perturbation at a decoupled fixed point without fine-tuning.
Tavis-Cummings (TC) cavity quantum electrodynamical effects, describing the interaction of N atoms with an optical resonator, are at the core of atomic, optical and solid state physics. The full ...numerical simulation of TC dynamics scales exponentially with the number of atoms. By restricting the open quantum system to a single excitation, typical of experimental realizations in quantum optics, we analytically solve the TC model with an arbitrary number of atoms with linear complexity. This solution allows us to devise the Quantum Mapping Algorithm of Resonator Interaction with N Atoms (Q-MARINA), an intuitive TC mapping to a quantum circuit with linear space and time scaling, whose N+1 qubits represent atoms and a lossy cavity, while the dynamics is encoded through 2N entangling gates. Finally, we benchmark the robustness of the algorithm on a quantum simulator and superconducting quantum processors against the quantum master equation solution on a classical computer.
We complete the non-perturbative calculations of the strange quark mass and the Lambda parameter in two flavor QCD by the ALPHA Collaboration. The missing lattice scale is determined via the kaon ...decay constant, for whose chiral extrapolation complementary strategies are compared. We also give a value for the scale r0 in physical units as well as an improved determination of the renormalization constant ZA.
Purpose
To evaluate the magnetic resonance imaging (MRI) characteristics of uveal melanoma (UM), to compare them with fundoscopy and ultrasound (US), and to validate them with histopathology.
Methods
...MR images from 42 UM were compared with US and fundoscopy, and on 14 enucleated cases with histopathology.
Results
A significant relationship between the signal intensity on T1 and pigmentation on histopathology was found (
p
=0.024). T1 hyperintense UM were always moderately or strongly pigmented on histopathology, while T1-hypointense UM were either pigmented or non-pigmented. Mean apparent diffusion coefficient (ADC) of the UM was 1.16 ± 0.26 × 10
−3
mm
2
/s. Two-thirds of the UM had a wash-out and the remaining a plateau perfusion time-intensity curve (TIC). MRI was limited in evaluating the basal diameter of flat tumors. US tends to show larger tumor prominence (0.5mm larger,
p
=0.008) and largest basal diameter (1.4mm larger,
p
<0.001). MRI was good in diagnosing ciliary body involvement, extrascleral extension, and optic nerve invasion, but limited on identifying scleral invasion. An increase of tumor prominence was associated with lower ADC values (
p
=0.030) and favored a wash-out TIC (
p
=0.028). An increase of tumor ADC correlated with a plateau TIC (
p
=0.011).
Conclusions
The anatomical and functional MRI characteristics of UM were comprehensively assessed. Knowing the MRI characteristics of UM is important in order to confirm the diagnosis and to differentiate UM from other intra-ocular lesions and because it has implications for treatment planning. MRI is a good technique to evaluate UM, being only limited in case of flat tumors or on identifying scleral invasion.
Due to Koelreuteria paniculata Laxm., high abundance in Novi Sad (Serbia) and previously confirmed biodiesel feedstock suitability, this study aimed to assess generative potential and yield, assess ...K. paniculata invasive risk, and investigate the influence of harvesting periods on the oil content and quality. Fifty-five specimens present in the Novi Sad inner-city core exhibited very high scores in the conducted invasiveness risk assessment (score 35/39). Determined good overall adaptability, growth and development, vitality and decorativeness of K. paniculata specimens, as well as the absence of phytopathological and entomological damages, due to lack of natural enemies, provided this species high unhindered yielding. The majority of investigated trees reached 5–10 m in height and canopy volumes from 10.1 to 70 m3, with an estimated more than 130 000–700 000 seeds produced per canopy. Seeds from one representative specimen were collected on different harvesting dates, at the end of August, September and October of 2019, and analyzed for oil content and quality for biodiesel production. With the average oil percentage of 22.8 w%, determined in the representative specimen, investigated 55 seed-bearing K. paniculata trees merely in the inner city core of Novi Sad, could produce 115 kg of oil. Since oil properties (<1 w% of free fatty acids and the acid number <2 mgKOH.g−1) and fatty acid profile (high content of monounsaturated fatty acids ≈72 w%) fit the requirements set in EN14214 biodiesel standard, regardless of the harvest date, harvest season can be extended to at least three months without compromising the oil quality for biodiesel production. Thus, intrinsic disservice of K. paniculata – high seed yielding can be shifted into a novel ecosystem service – quality biodiesel production. Aiming to avoid viable seed deposition in the ground and formation of the invasive seed bank, early August harvest can be recommended.
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•Koelreuteria paniculata showed high invasiveness risk in the city of Novi Sad.•K. paniculata had good overall adaptability and high yielding capacity.•Oil quality fit the requirements of EN14214 standard, regardless of the harvest date.•K. paniculata harvest can last at least 3 months without compromising the oil quality.
Anomalous magnetic moment of the muon,
a
μ
=
(
g
μ
-
2
)
/
2
, is one of the most precisely measured quantities in particle physics and it provides a stringent test of the Standard Model. The planned ...improvements of the experimental precision at Fermilab and at J-PARC propel further reduction of the theoretical uncertainty of
a
μ
. The hope is that the efforts on both sides will help resolve the current discrepancy between the experimental measurement of
a
μ
and its theoretical prediction, and potentially gain insight into new physics. The dominant sources of the uncertainty in the theoretical prediction of
a
μ
are the errors of the hadronic contributions. I will discuss recent progress on determination of hadronic contributions to
a
μ
from lattice calculations.
Uveal Melanoma (UM) is the most common primary malignant ocular tumor. The high soft tissue contrast and spatial resolution, and the possibility of generating 3D volumetric and functional images, ...make Magnetic Resonance Imaging (MRI) a valuable diagnostic imaging technique in UM. Current clinical MRI protocols, however, are not optimized for UM and therefore lack the quality for accurate assessments. We therefore developed a dedicated protocol at a 3 Tesla MRI, using an eye coil, consisting of multi-slice 2D sequences, different isotropic sequences and diffusion and perfusion-weighted images. This protocol was prospectively evaluated in 9 uveal melanoma patients. The multi-slice 2D sequences had the highest in-plane resolution, being the most suited for lesion characterization and local extension evaluation. The isotropic 3D Turbo-Spin Echo (TSE) sequences were the most suitable for accurate geometric measurements of the tumor and are therefore important for therapy planning. Diffusion and perfusion-weighted images aid in differentiating benign from malignant lesions and provide quantitative measures on tumor hemodynamics and cellularity, which have been reported to be effective in predicting and assessing treatment outcome. Overall, this dedicated MRI protocol provides high-quality imaging of UM, which can be used to improve its diagnosis, treatment planning, and follow-up.
To analyze the clinical characteristics of a serous retinopathy associated with mitogen-activated protein kinase kinase (MEK) inhibition with binimetinib treatment for metastatic cutaneous melanoma ...(CM) and uveal melanoma (UM), and to determine possible pathogenetic mechanisms that may lead to this retinopathy.
Prospective observational, cohort-based, cross-sectional study.
Thirty CM patients and 5 UM patients treated with the MEK inhibitor binimetinib (CM) or a combination of binimetinib and the protein kinase C inhibitor sotrastaurin (UM).
Extensive ophthalmic examination was performed, including Early Treatment of Diabetic Retinopathy Study best-corrected visual acuity, applanation tonometry, slit-lamp examination, indirect ophthalmoscopy, digital color fundus photography, and optical coherence tomography (OCT). In selected cases, additional examinations were performed, including visual field testing and electro-oculography (EOG). Blood samples were obtained from 3 CM patients and 3 UM patients to analyze the presence of autoantibodies against retinal and retinal pigment epithelium (RPE) proteins.
Visual symptoms, visual acuity, fundus appearance, characteristics on OCT, fundus autofluorescence (FAF), and EOG.
Six CM patients (20%) and 2 UM patients (40%) reported visual symptoms during the study. The median time to the onset of symptoms, which were all mild and transient, was 3.5 days (range, <1 hour to 3 weeks). On OCT, subretinal fluid (SRF) was detected in 77% of CM patients and 60% of UM patients. In the 26 patients with SRF, the fovea was affected in 85%. After the start of the medication, an EOG was performed in 19 eyes of 11 patients; 16 of these eyes (84%) developed SRF on OCT. Fifteen of these eyes (94%) showed an abnormal Arden ratio (<1.65). A broad pattern of anti-retinal antibodies was found in 3 CM patients and 2 UM patients tested, whereas anti-RPE antibodies were detected in all 6 tested patients.
A time-dependent and reversible serous retinopathy can develop both in patients with metastatic CM and UM treated with binimetinib. A minority of patients develop visual symptoms, which are generally mild and transient. A cause of binimetinib-associated serous retinopathy may be toxicity of medication, but autoantibodies also may be involved.
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