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Abstract We investigate the effects of exact gluon kinematics on the parameters of the Golec-Biernat–Wüsthoff, and Bartels–Golec-Biernat–Kowalski saturation models. The resulting fits show some differences, particularly, in the normalization of the dipole cross section $$\sigma _0$$ σ 0 . The refitted models are used for the dijet production process in DIS to describe HERA data and investigate the effects of the Sudakov form factor at the future Electron Ion Collider.

Abstract We review recent results for forward jests at the LHC and EIC as obtained within small-x Improved Transverse Momentum Dependent factorization (ITMD). In addition to elementary overview of various approaches to perturbative QCD at high energy, including High Energy Factorization, Color Glass Condensate and ITMD, we describe the Monte Carlo implementation and discuss the existing and unpublished phenomenological results for forward dijets.

Abstract We present a state-of-the-art computation for the production of dijets in proton-proton and proton-lead collisions at the LHC, in forward rapidity domains covered by the ATLAS calorimeter and the planned FoCal extension of the ALICE detector. We use the small-x improved TMD (ITMD) formalism, together with collinearly improved TMD gluon distributions and full b-space Sudakov resummation, and discuss nonperturbative corrections due to hadronization and showers using the Pythia event generator. We observe that the production of forward dijets in proton-nucleus collisions at moderately low p T is an excellent probe of saturation effects, and demonstrate that the Sudakov resummation does not alter the suppression of the cross section.

In this study we incorporate the Sudakov form factor into the dipole factorization formula, where the hard scale of the former is provided by the photon virtuality Q2. We obtain a general formula which we then apply to the well-known GBW and BGK saturation models. Parameters of the above Sudakov-improved models are successfully fitted to the F2 data from HERA. We observe, in particular, that inclusion of the Sudakov factor on top of the GBW model improves description of data at large Q2.

Abstract We propose a novel way of studying the gluon number density (the so-called Weizsäcker–Williams gluon distribution) using the planned Electron Ion Collider. Namely, with the help of the azimuthal correlations between the total transverse momentum of the dijet system and the scattered electron, we examine an interplay between the effect of the soft gluon emissions (the Sudakov form factor) and the gluon saturation effects. The kinematic cuts are chosen such that the dijet system is produced in the forward direction in the laboratory frame, which provides an upper bound on the probed longitudinal fractions of the hadron momentum carried by scattered gluons. Further cuts enable us to use the factorization formalism that directly involves the unpolarized Weizsäcker–Williams gluon distribution. We find this observable to be very sensitive to the soft gluon emission and moderately sensitive to the gluon saturation.

Abstract A common library, TMDlib2, for Transverse-Momentum-Dependent distributions (TMDs) and unintegrated parton distributions (uPDFs) is described, which allows for easy access of commonly used TMDs and uPDFs, providing a three-dimensional (3D) picture of the partonic structure of hadrons. The tool TMDplotter allows for web-based plotting of distributions implemented in TMDlib2, together with collinear pdfs as available in LHAPDF.

We discuss central-forward dijet production at LHC energies within the framework of high energy factorization. In our study, we profit from the recent progress on consistent merging of Sudakov resummation with small-x effects, which allows us to compute two different gluon distributions which depend on longitudinal momentum, transverse momentum and the hard scale of the process: one for the quark channel and one for the gluon channel. The small-x resummation is included by means of the BK equation supplemented with a kinematic constraint and subleading corrections. We test the new gluon distributions against existing CMS data for transverse momentum spectra in forward-central dijet production. We obtain results which are largely consistent with our earlier predictions based on model implementation of Sudakov form factors. In addition, we study dijet azimuthal decorrelations for the forward-central jets, which are known to be sensitive to the modeling of soft radiation.

Abstract Using the framework that interpolates between the leading power limit of the color glass condensate and the high energy (or $$k_{T}$$ k T ) factorization we calculate the direct component of the forward dijet production in ultra-peripheral $$\mathrm {Pb}$$ Pb – $$\mathrm {Pb}$$ Pb collisions at CM energy $$5.1\,\mathrm {TeV}$$ 5.1 TeV per nucleon pair. The formalism is applicable when the average transverse momentum of the dijet system $$P_{T}$$ P T is much bigger than the saturation scale $$Q_{s}$$ Q s , $$P_{T}\gg Q_{s}$$ P T ≫ Q s , while the imbalance of the dijet system can be arbitrary. The cross section is uniquely sensitive to the Weizsäcker–Williams (WW) unintegrated gluon distribution, which is far less known from experimental data than the most common dipole gluon distribution appearing in inclusive small-x processes. We have calculated cross sections and nuclear modification ratios using WW gluon distribution obtained from the dipole gluon density through the Gaussian approximation. The dipole gluon distribution used to get WW was fitted to the inclusive HERA data with the nonlinear extension of unified BFKL + DGLAP evolution equation. The saturation effects are visible but rather weak for realistic $$p_{T}$$ p T cut on the dijet system, reaching about 20% with the cut as low as $$6\,\mathrm {GeV}$$ 6 GeV . We find that the LO collinear factorization with nuclear leading-twist shadowing predicts quite similar effects.

There was a mistake in the normalization of the histograms representing the differenial cross section as a function of the azimuthal angle between the jets: figure 3 left and figure 4 left in the original paper [1].

We provide a description, within the High Energy Factorization formalism, of central–forward dijet correlation data measured by the CMS experiment and the predictions for nuclear modification ratio RpA in p + Pb collisions. In our study, we use the unintegrated gluon density derived from the BFKL and BK equations supplemented with subleading corrections and a hard scale dependence. The latter is introduced at the final step of the calculation by re-weighting the Monte Carlo generated events using suitable Sudakov form factors, without changing the total cross section. We achieve a good description of data in the whole region of the azimuthal angle.

Context: Oxidative stress is an important factor for vitreomacular interface disease development in a theoretical model., Purpose: The aim of the study was to evaluate the correlation between oxidative stress in the human epiretinal membrane (ERM) and retinal morphological changes., Material and Methods: The study included patients scheduled for vitrectomy with epiretinal membrane removal. LogMAR best corrected visual acuity was assessed and optical coherence tomography was performed. Patients were divided into three groups: Type 1 - epiretinal membrane with premacular fibrosis; type 2 - epiretinal membrane with co-existing layer hole; and type 3 - ERM with co-existing full-thickness macular hole. During vitrectomy, epiretinal membranes were collected. Total oxidant status was determined by an automated colorimetric method in homogenates of epiretinal membrane., Statistical Analysis: The Mann-Whitney U test, Kruskal-Wallis test and Spearman linear correlation analysis were used. Statistical significance was set with a level of α = 0.05., Results: Twenty-one Caucasian women (60%) and 14 men (40%) were included in the study. The average age of participants was 74.7 years (95% CI: 71.13-75.45). The mean best corrected visual acuity LogMAR value in the group was 0.8 (95% CI: 0.9-0.7). The mean ratio of total oxidant status to protein level in the collected samples was 0.161 (95% CI: 0.08-0.23) µmol/mg of protein. No correlation was found between total oxidant status and the degree of morphological retinal changes., Conclusion: The study found no significant correlation between the level of oxidative stress in epiretinal membrane and retinal morphological changes., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Wilczyński, Zalejska-Fiolka, Sapeta-Wieckowska, Sarnat-Kucharczyk and Rokicki.)

Purpose: To employ ultrahigh-resolution (UHR) optical coherence tomography (OCT) for investigation of the early wound healing process in corneal epithelium., Methods: A custom-built UHR-OCT system assessed epithelial healing in human keratoconic cornea after epi-off crosslinking (CXL) procedure and a wound healing model in rabbits with iatrogenic corneal injury. 3D OCT data sets enhanced obtaining epithelial thickness maps and evaluation of reepithelization stage. Accompanying changes in deeper corneal microarchitecture were analysed., Results: The mean central corneal thickness in 40 eyes with keratoconus at baseline was 482.7 ± 38.2 μm, while mean central epithelial thickness (CET) was 43.8 ± 6.4 μm. At the final visit 20 ± 5 days post-CXL procedure, CET was 35.0 ± 5.8 μm, significantly thinner after reepithelization (p < 0.001). Surgical success was assessed at the final visit through the demarcation line (DL), identified at 43.7 ± 13.5% stromal depth. In rabbits, the mean CET in 20 eyes at baseline was 35.9 ± 2.6 μm. In rabbits that revealed complete wound closure (10/20 eyes) at the last study day at 72 hr, CET was significantly thinner compared to baseline (30.4 ± 2.8 μm versus 35.4 ± 2.9 μm, p = 0.005). An intra-stromal landmark indicating early keratocyte apoptosis was measured at 30.0 ± 5.1% stromal depth. Epithelial thickness maps showed the time-course of corneal healing., Conclusion: Ultrahigh-resolution (UHR)-OCT provided precise assessment of epithelial wound and its healing by 3D-mapping. In addition, microarchitectural changes in the cornea in early phases of epithelial healing were revealed., (© 2019 The Authors. Acta Ophthalmologica published by John Wiley & Sons Ltd on behalf of Acta Ophthalmologica Scandinavica Foundation.)

A new calculation using off-shell matrix elements with TMD parton densities supplemented with a newly developed initial state TMD parton shower is described. The calculation is based on the KaTie package for an automated calculation of the partonic process in high-energy factorization, making use of TMD parton densities implemented in TMDlib. The partonic events are stored in an LHE file, similar to the conventional LHE files, but now containing the transverse momenta of the initial partons. The LHE files are read in by the Cascade package for the full TMD parton shower, final state shower and hadronization from Pythia where events in HEPMC format are produced. We have determined a full set of TMD parton densities and developed an initial state TMD parton shower, including all flavors following the TMD distribution. As an example of application we have calculated the azimuthal de-correlation of high [Formula: see text] dijets as measured at the LHC and found very good agreement with the measurement when including initial state TMD parton showers together with conventional final state parton showers and hadronization.

We present imaging of corneal pathologies using optical coherence tomography (OCT) with high resolution. To this end, an ultrahigh-resolution spectral domain OCT (UHR-OCT) system based on a broad bandwidth Ti:sapphire laser is employed. With a central wavelength of 800 nm, the imaging device allows to acquire OCT data at the central, paracentral and peripheral cornea as well as the limbal region with 1.2 µm x 20 µm (axial x lateral) resolution at a rate of 140 000 A-scans/s. Structures of the anterior segment of the eye, not accessible with commercial OCT systems, are visualized. These include corneal nerves, limbal palisades of Vogt as well as several corneal pathologies. Cases such as keratoconus and Fuchs's endothelial dystrophy as well as infectious changes caused by diseases like Acanthamoeba keratitis and scarring after herpetic keratitis are presented. We also demonstrate the applicability of our system to visualize epithelial erosion and intracorneal foreign body after corneal trauma as well as chemical burns. Finally, results after Descemet's membrane endothelial keratoplasty (DMEK) are imaged. These clinical cases show the potential of UHR-OCT to help in clinical decision-making and follow-up. Our results and experience indicate that UHR-OCT of the cornea is a promising technique for the use in clinical practice, but can also help to gain novel insight in the physiology and pathophysiology of the human cornea.

Purpose: The purpose of this study was to analyze factors determining retinal arterial and venous responses to stimulation with diffuse luminance flicker in healthy subjects., Methods: We retrospectively analyzed results obtained in 374 healthy subjects who had previously participated in clinical studies in our department. A total of 153 subjects underwent a protocol in which flicker stimulation was delivered through the fundus camera at 8 Hz (protocol 1), separating measurement and stimulation light depending on the wavelength, and 221 subjects underwent a protocol in which diffuse luminance flicker was delivered at 12.5 Hz with high modulation depth (protocol 2). We investigated whether sex, systemic blood pressure, baseline vessel size, blood plasma concentration of fasting glucose and hematocrit, and serum concentration of cholesterol, triglycerides, creatinine and C-reactive protein influenced the retinal vascular response to flicker stimulation., Results: Flicker responses in arteries and veins were more pronounced in protocol 2 than in protocol 1 (P < 0.001, each). In both of the protocols the vascular response to stimulation with diffuse luminance flicker was larger in smaller vessels (P between 0.001 and 0.016). In protocol 2 the retinal arterial flicker response was negatively associated with cholesterol serum levels (P = 0.033); in protocol 1, only a tendency toward this effect was observed (P = 0.056)., Conclusions: The present analysis indicates that retinal arterial and venous responses to stimulation with diffuse luminance flicker depend on the way the stimulation is delivered through the fundus camera. In addition, the flicker response varied with vessel size, that is, the smaller the vessel width, the larger the flicker response. Finally, our data indicate that, even within the normal range, higher cholesterol serum levels are associated with lower hyperemic flicker responses.