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To assess ocular microvasculature changes using optical coherence tomography angiography (OCTA) in pediatric patients with inflammatory bowel disease (IBD). Patients (aged 6–18 years) with IBD were recruited between September 2021 and May 2023. All eligible participants underwent comprehensive clinical assessment and laboratory investigation. Patients with functional gastrointestinal disorders served as the controls. This study assessed specific IBD phenotypes, disease duration, clinical and endoscopic activity indices, laboratory markers, and medication histories. OCTA was utilized to evaluate ocular microvasculature changes in both groups. A total of 63 children (mean age 12.9 ± 3.3 years) were enrolled, comprising 38 in the IBD group (16 ulcerative colitis, 22 Crohn's disease, and 25 in the control group). Most patients in the IBD group were in remission or had mild‐to‐moderate disease activity at enrollment. Analysis of the OCTA results revealed significant differences in the choroidal luminal area and total choroidal area between the IBD and control groups. The study identified distinct ocular microvasculature changes in pediatric IBD patients through OCTA, suggestive of potential systemic endothelial dysfunction. These findings underscore the utility of OCTA in evaluating microvascular alterations associated with pediatric IBD, offering insights into potential systemic complications linked to inflammation in IBD patients. Inflammatory bowel diseases (IBD) encompass systemic inflammation due to immune and nonimmune cell activation leading to microvascular endothelial damage.Endothelium plays a crucial role in various physiological processes like vasoconstriction/vasodilation, coagulation, and leukocyte migration.IBD patients often exhibit early endothelial dysfunction in the gut microvascular system. Inflammatory bowel diseases (IBD) encompass systemic inflammation due to immune and nonimmune cell activation leading to microvascular endothelial damage. Endothelium plays a crucial role in various physiological processes like vasoconstriction/vasodilation, coagulation, and leukocyte migration. IBD patients often exhibit early endothelial dysfunction in the gut microvascular system. Optical coherence tomography angiography has been used for the first time in children to evaluate endothelial dysfunction in pediatric IBD.The study identified distinct ocular microvasculature changes in pediatric IBD patients and a significant inverse correlation between platelet count and choroidal vasculature.The findings suggest a potential link between ocular microvascular alterations and systemic endothelial dysfunction in pediatric IBD emphasizing that IBD‐related inflammation goes beyond the gut, impacting the microvasculature system of the eye. Optical coherence tomography angiography has been used for the first time in children to evaluate endothelial dysfunction in pediatric IBD. The study identified distinct ocular microvasculature changes in pediatric IBD patients and a significant inverse correlation between platelet count and choroidal vasculature. The findings suggest a potential link between ocular microvascular alterations and systemic endothelial dysfunction in pediatric IBD emphasizing that IBD‐related inflammation goes beyond the gut, impacting the microvasculature system of the eye.

In view of Run 4 at the LHC, presently scheduled from 2029 onwards, ALICE is pursuing several upgrades to further extend its physics reach. In order to improve heavy-flavor hadron and dielectron measurements which rely on secondary vertexing, a reduction of the material budget of the innermost layers of the Inner Tracking System is needed. This can be achieved with bent pixel sensors, arranged in half-cylinder shapes with integrated power lines and data buses, allowing to get rid of most of the supporting structure and of the water cooling. Moreover, a new Forward Calorimeter (FoCal), covering pseudorapidities of 3.2<η<5.8, has been proposed to measure small-x (down to 10−6) gluon distributions via prompt photon production. The FoCal will be composed of a highly granular Si+W electromagnetic calorimeter combined with a conventional sampling hadronic calorimeter, and will significantly enhance the scope of ALICE for inclusive and correlation measurements with mesons, photons, and jets. For Run 5 and beyond, the ALICE 3 project has been proposed. It consists of a novel compact detector based on monolithic silicon sensors, with ultra-thin layers near the vertex, high readout rate capabilities, superb pointing resolution, excellent tracking and particle identification over a large acceptance. Such a detector enables a rich physics program, ranging from electromagnetic probes at ultra-low transverse momenta to precision physics in the charm and beauty sector. For particle identification, a sequence of detector systems is foreseen: a combination of a Time-Of-Flight system, a Ring-Imaging Cherenkov detector, an electromagnetic calorimeter, a muon identifier, and a dedicated forward detector for ultra-soft photons. In these proceedings, the upgrade plans will be shown together with the status of R&D on ITS3 and FoCal and with the concepts and requirements of ALICE 3.

The reliability of several density functional theory (DFT) functionals and of the Möller–Plesset second-order perturbation theory calculations with modified basis sets (mp2mod) approach in describing cation−π interactions is systematically investigated by benchmarking their performances with respect to high quality reference CCSD(T) calculations of the binding energies between alkaline cations of varying radius (Na+, K+, Rb+, and Cs+) and three aromatic species (benzene, phenol, and catechol). For this class of noncovalent interaction, mp2moddelivers, on average, results in very good agreement with the reference CCSD(T) data, yet at a very small computational cost, exploiting the reduced dimensions of the modified basis set. Conversely, the tested DFT functionals show a more erratic behavior, with different performances depending on both the investigated system and the combination of the employed functional and basis set. The mp2modcomputational convenience is further exploited to extensively sample two-dimensional interaction energy surfaces of all investigated cation−π systems, which allow for a deeper insight on the effect of the increasing number of hydroxyl substituents, revealing the insurgence, upon substitution, of alternative minima, evident in particular for the smaller cations. The present results strongly support for further applications of the mp2modmethod to study a larger variety of aromatic/metal cation species, relevant both in biological processes and in technological applications.

Aims. To further characterise CDKL5‐related disorder, previously classified as an early‐onset seizure variant of Rett syndrome, which is currently considered a specific and independent early‐infantile epileptic encephalopathy. Methods. We describe the epileptic phenotype and neurocognitive development in three girls with CDKL5mutations showing severe neurodevelopmental impairment, with different epileptic phenotypes and severity. Results. The patients differed regarding age at epilepsy onset, seizure frequency, duration of “honeymoon periods”, as well as EEG features. The “honeymoon period”, defined as a seizure‐free period longer than two months, represented, in our case series, a good indicator of the epilepsy outcome, but not of the severity of developmental impairment. However, even during the “honeymoon period”, the interictal EEG showed epileptiform abnormalities, slowing, or a disappearance of physiological pattern. The natural history of CDKL5disorder was compared between the three girls, focusing on the relationship between electroclinical features and neurological development. Conclusion. Our findings suggest that CDKL5mutations likely play a direct role in psychomotor development, whereas epilepsy is one of the clinical features associated with this complex disorder.

The redox and proton transfer processes involving the several dimers arising from quinones are studied by quantum mechanical methods using second order perturbation theory (MP2) and a medium size basis set optimized for reproducing dispersion interactions. Furthermore, bulk solvent effects are taken into account by the polarizable continuum solvent (PCM) approach possibly integrated by two explicit water molecules for an improved description of the cybotactic region. Our results indicate that several neutral and anionic dimers are kept together mainly by strong hydrogen bonds, but dispersion forces introduce additional non-negligible effects. The computed energy paths indicate that a proton transfer process should accompany the two-electron reduction of quinhydrone and that two dimers in the reduced form can be simultaneously present in solution, in agreement with available experimental data.

A theoretical study on the singlet triplet energy splitting in a m-phenylene bridged organic diradical has been performed using an original computational protocol developed in our group. The method is based on post Hatree–Fock calculations and has proven to provide accurate results with reasonable computational effort. By virtue of such efficiency, the full PES of both the singlet and triplet states as a function of the two “soft” torsional degrees of freedom at the meta position of the ring has been explored. In agreement with literature findings, we found a pronounced dependence of the sign of the energy gap from the torsional angles. Finally, exploiting the two-dimensional surface, a statistical analysis is carried out at low temperatures and a comparison with available experimental data addressed.

A fast and efficient computational protocol, devised for the accurate calculation of singlet–triplet magnetic splittings in organic diradicals, is here applied to several promising organic magnets, recently considered in the literature. The very good agreement with the measured values, obtained for all investigated compounds, suggests that the present approach could successfully flank the experiment in the design of novel magnetic materials. Indeed, some structure–magnetic properties relationships were rationalized thanks to the theoretical soundness of the adopted multireference approach. In particular the different effects of N· and NO· magnetic moieties, as well as the role of lateral aliphatic chains and phenyl pendant substituents, are discussed in detail.

The optimal coverage of a silicon(111) surface func-tionalized with small organic chains is identified by a computational approach that combines quantum mechanical calculations and classical molecular dynamics simulations. Quantum mechanics is used to evaluate the binding energy of the adsorbed organic molecules. A specific and accurate force-field, developed previously, is employed to perform all-atom molecular dynamic simulations of differently functionalized surfaces in solution. Several coverage percentages with both amine- and methyl-terminated propyl chains are compared through their free energies, pair correlation functions, solvent distributions, and internal conformations. Both types of functionalization yield a coating of ∼55%, but the alkyl-amine coverage free energy is remarkably lower in all cases due to more favorable interactions with the polar solvent.

A new, fast, and efficient computational protocol for the accurate calculation of singlet−triplet magnetic splittings in organic diradicals is tested and validated. This procedure essentially consists of three steps: the adoption of modified virtual orbitals (MVO) and a mixed variational−perturbational approach (CSPA) are now combined with a third method that exploits the reduction of the configurational space dimensions achieved by fragmentation/localization criteria. This innovative approach is successfully tested on four different substituted m-phenylene bis(tert-butyl) nitroxides, which show paramagnetic behavior, by computing singlet−triplet energy gaps and comparing them with their experimental counterparts.

Cation−π interactions and their possible competition with other noncovalent interactions (NCI) might play a key role in both dopamine- and eumelanin-based bioinspired materials. In this contribution, to unravel the delicate interplay between cation−π interactions and other possible competing forces, the configurational space of noncovalent complexes formed by dopamine or eumelanin precursors (o-benzoquinone, DHI and a semiquinone dimer) and three different cations (Na+, K+, and NH4+) is sampled by means of accurate ab initio calculations. To this end, we resort to the mp2modmethod, recently validated by us for benzene–, phenol–, and catechol–cation complexes, whose computational convenience allows for an extensive exploration of the cation–molecule interaction energy surface, by sampling a total of more than 104arrangements. The mp2modinteraction energy landscapes reveal that, besides the expected cation−π driven arrangements, for all considered molecule–cation pairs the most stable complexes are found when the cation lies within the plane containing the six-membered ring, thus maximizing the σ-type interaction with the oxygen’s lone pairs. Due to the loss of aromaticity, the σ-type/cation−π strength ratio is remarkably large in o-benzoquinone, where cation−π complexes seem unlikely to be formed. The above features are shared among all considered cations but are significantly larger when considering the smaller Na+. Besides delivering a deeper insight onto the NCI network established by the considered precursors in the presence of ions, the present results can serve as a reference database to validate or refine lower level methods, as, for instance, the force fields employed in classical simulations.

The permanent scatterers (PS) technique is a multi-interferogram algorithm for DInSAR analyses developed in the late nineties to overcome the difficulties related to the conventional approach, namely, phase decorrelation and atmospheric effects. The successful application of this technology to many geophysical studies is now pushing toward further improvements and optimizations. A possible strategy to increase the number of radar targets that can be exploited for surface deformation monitoring is the adoption of parametric super-resolution algorithms that can cope with multiple scattering centres within the same resolution cell. In fact, since a PS is usually modelled as a single pointwise scatterer dominating the background clutter, radar targets having cross-range dimension exceeding a few meters can be lost (at least in C-band datasets), due to geometrical decorrelation phenomena induced in the high normal baseline interferograms of the dataset. In this paper, the mathematical framework related to higher-order SAR interferometry is presented as well as preliminary results obtained on simulated and real data. It is shown how the PS density can be increased at the price of a higher computational load.

We present an analysis of electron transfer in a molecular structure containing two phenyl rings connected by a methylene barrier, with the addition of a donor group (NH2) on one ring and an acceptor group (NO2) on the other. Such molecules are among those currently being considered for the implementation of molecular circuits for information processing. We have performed both a study of the response of electron polarization to the application of an external electrostatic perturbation, and an analysis of the time-dependent behavior of electron transfer across the barrier. A detailed evaluation of the electron affinity and of the ionization energy of the molecular structure under investigation has also been performed, obtaining results that show the inadequacy of representations in terms of simple HOMO and LUMO orbitals.

The near IR–visible absorption and electroabsorption (Stark) spectra of the title compounds are studied by using a vibronic model Hamiltonian. The model, very simple in its electronic part, includes both bond and local (on-site) vibrations, whose separate effects on the optical properties are also investigated. We have found that bond vibrations, often neglected in model calculations, play a significant role in the lineshape profile. Relevant molecular parameters, such as dipole moment and polarizability, in both the ground and the excited states, are computed within the framework of the present model. Good agreement with the experimentally available results is found.

Satellite mounted Synthetic Aperture Radars (SAR) provide informationof the amplitude of the backscatterer its phase. This corresponds to the totaltravel time (source receiver and back), plus the phase of the scatterer itself.SAR interferometry yields the image of the differences of the phases takenin two successive passes. Or in the same pass if two receivers are availableon board; these images give a good digital elevation model of the terrain,with a vertical resolution that could be in the meter range. Millimetric motionof large areas of the terrain or of corner reflectors can also be measured withgood reliability; the system then measures subsidence, co-seismic motions andsmall motions of buildings and constructions. The coherence of t e interferometric pair, i.e., the permanence of the scattering characteristics of the terrain from one pass to the next combined with the more usual backscatterer amplitude, leads to high quality image segmentation. The possibilities and the limits of this technique are summarized.

Some aspects of the dynamics of two-electron transfer between metallic centers separated by a bridge of identical sites are briefly discussed by help of an effective Hamiltonian formalism.

We have investigated the optical conductivity spectra of [Ru(pyzRu)3]m+chain (pyz=pyrazine) through a two-band Hubbard Hamiltonian. It is shown that the main features of absorption spectra, observed experimentally for various degrees of oxidation (m), may be well reproduced within this simple model. The spectra, for different values of the relevant parameters in the most suitable range for reproducing the experimental results, have been analysed in terms of various quantities obtained from the many-particle eigenstates, in order to give a realistic assignment of the observed peaks and their dependence on the values of the parameters. It is shown that the characteristic shift of spectral weight from high to low frequency upon reduction is related to strong charge fluctuations between metallic and ligand bands.