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White matter pathologies are critically involved in the etiology of vascular cognitive impairment-dementia (VCID), Alzheimer's disease (AD), and Alzheimer's disease and related diseases (ADRD), and therefore need to be considered a treatable target ( Roseborough A, Hachinski V, Whitehead S. White matter degeneration - a treatable target? Roseborough et al. JAMA Neurol [Internet]. 2020 Apr 27;77(7):793-4, [1] . To help address this often-missed area of research, several workshops have been sponsored by the Leo and Anne Albert Charitable Trust since 2015, resulting in the incorporation of "The Albert Research Institute for White Matter and Cognition" in 2020. The first annual "Institute" meeting was held virtually on March 3-4, 2021. The Institute provides a forum and workspace for communication and support of the advancement of white matter science and research to better understand the evolution and prevention of dementia. It serves as a platform for young investigator development, to introduce new data and debate biology mechanisms and new ideas, and to encourage and support new research collaborations and directions to clarify how white matter changes, with other genetic and health risk factors, contribute to cognitive impairment. Similar to previous Albert Trust-sponsored workshops (Barone et al. in J Transl Med 14:1-14, [2]; Sorond et al. in GeroScience 42:81-96, [3]), established expert investigators were identified and invited to present. Opportunities to attend and present were also extended by invitation to talented research fellows and younger scientists. Also, updates on institute-funded research collaborations were provided and discussed. The summary that follows is a synopsis of topics and discussion covered in the workshop.

Additional file 1: Table S.1. Characteristics of the patients admitted to the main intensive care unit of Umberto I teaching hospital of Rome between 1st March and 4th April 2020. Results are expressed as number (percentage), mean (standard deviation) or median (interquartile range). Table S.2. Type and frequency of all healthcare-associated infections (HAIs) registered by the active surveillance system among the patients admitted to the main intensive care unit of Umberto I teaching hospital of Rome between 1st March and 4th April 2020. Results are expressed as number (percentage).

The aim of this study is to assess the effect of contact time, contact distance and the use of personal protective equipment on the determination of SARS-CoV-2 infection in healthcare workers (HCWs). This study consists of an analysis of data gathered for safety reasons at the Sapienza Teaching Hospital Policlinico Umberto I in Rome through the surveillance system that was put into place after the worsening of the COVID-19 pandemic. The studied subjects consist of HCWs who were put under health surveillance, i.e., all employees who were in contact with subjects who were confirmed to have tested positive for SARS-CoV-2. The HCWs under surveillance were monitored for a period encompassing ten days after the date of contact, during which they undertook nasopharyngeal swab tests analysed through RT-PCR (RealStar® SARS-CoV-2 Altona Diagnostic–Germany). Descriptive and univariate analyses have been undertaken, considering the following as risk factors: (a) no personal protective equipment use (PPE), (b) Distance &lt, 1 m between the positive and contact persons, (c) contact time &gt, 15′. Finally, a Cox regression and an analysis of the level of synergism between factors, as specified by Rothman, were carried out. We analysed data from 1273 HCWs. Of these HCWs, 799 (62.8%) were females, with a sample average age of 47.8 years. Thirty-nine (3.1%) tested positive during surveillance. The overall incidence rate was 0.4 per 100 person-days. Time elapsed from the last exposure and a positive RT-PCR result ranged from 2 to 17 days (mean = 7, median = 6 days). In the univariate analysis, a distance &lt, 1 m and a contact time &gt, 15′ proved to be risk factors for the SARS-CoV-2 infection, with a hazard ratio (HR) of 2.62 (95% CI: 1.11–6.19) and 3.59 (95% IC: 1.57–8.21), respectively. The synergism analysis found the highest synergism between the “no PPE use” x “Contact time”. The synergy index S remains strongly positive also in the analysis of the factors “no PPE use” x “Distance” and “Time of contact” x “Distance”. This study confirms the absolute need to implement safety protocols during the pandemic and to use the correct PPE within health facilities in order to prevent SARS-CoV-2 infection. The analysis shows that among the factors considered (contact time and distance, no use of PPE), there is a strong synergistic effect.

Symposium O - Materials aspects of art characterization, conservation and restoration - O/P.20.

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This contribution describes the results of some recent studies concerning the excited state behavior of nucleic acid bases, where solvent and stacking effect are included. Our computational approach is based on PBE0 and TD-PBE0 geometry optimizations, while bulk solvent effects are taken into account by the Polarizable Continuum Model, with the possible inclusion of the solvent molecules of the first solvation shell. This approach provides accurate absorption and emission spectra both for pyrimidine and purine bases and is able to explain solvent effect on the excited state lifetimes of uracil-like molecules. Solvent indeed modulates the accessibility of an extra decay channel for the bright excited state, involving an underlying dark state. The effect of base stacking, investigated on 9-methyl-adenine stacked dimers and trimers, on the absorption and emission spectra is also fully reproduced by our calculations. Although light absorption leads to a state (SB) delocalized over different adenine molecules, excited state geometry optimization indicates that afterward it evolves into a state where the excitation is localized on a single base. Analysis of the excited state potential energy surfaces shows that SB can easily decay into the lowest energy excited state (SCT). SCT is a dark excimer produced by inter-monomer charge transfer between two stacked bases

Pulsed laser deposition is a technique used since twenty years ago for the production of nanoparticles films. Laser pulses with a duration in the femtosecond, picosecond and nanosecond range have been employed for material processing as well as for ablation and deposition of semiconductors, superconductive materials, ceramics, magnetic layers and multilayers. Recently, results on the ultra-short pulsed laser deposition (uPLD) revealed this technique as particularly interesting for the deposition of magnetic nanogranular films. This review deals with the innovative findings and the potential developments related to the use of uPLD. The following points are addressed: first, the peculiar shape and orientation of the nanoparticles in the films obtained by the uPLD technique; second, the capability of uPLD to reproduce the stoichiometry in target material in the deposited film; third, the possibility to produce nanogranular amorphous film from polycrystalline target; fourth, the potentiality of uPLD in tailoring the magnetic softness of the film by means of a co-deposition of hard and soft magnetic nanoparticles. Finally, we briefly discuss the potential applications of the uPLD in the production of composite nanogranular films with interesting performances for improved magnetostrictive and magnetoresisitive micro-devices.

Atomic Force Microscopy (AFM) has been used for the characterization of nanometric particles produced in rich flames. Very small particles (about 2 nm) have been found in pre-inception region of soot forming premixed flames, whereas both small nanoparticles as well as large soot particles have been found in the soot region of the flames. The smaller particles are very flat in shape if compared with the bigger ones, and this probably depends upon the different nature of the collected particles. Particle size distribution functions are reported for different sampling conditions. The results of AFM measurements are in good agreement with previous measurements performed with ultraviolet (UV) light scattering/extinction technique on the same flames.

Inverse water-in-oil microemulsions are suspensions of spherical droplets of water coated by a monolayer of surfactant molecules, immersed in oil. We have studied WAD (water/AOT/decane, where AOT denotes sodium-bis-di-ethyl-sulfosuccinate) microemulsions far from critical points and near the percolative transition from electrically insulating to electrically conducting. The AOT molecules have a bulky tail and a small head so that the coating film has a spontaneous curvature toward water. Owing to this reason, water droplets are quite stable and, from 10 to 50°C, a large one- phase region, called L2 phase extends in the ternary phase triangle from the decane corner into the middle of the phase diagram. A percolation line is found in this region. We have observed optical nonlinearity near the percolation line and far from the one-phase two- phase boundary line. In this point, the material turbidity is very low and the material appears to be suitable for several nonlinear optical devices.

UV-visible extinction and scattering and two extra situ sampling techniques: atomic force microscopy (AFM) and differential mobility analysis (DMA) are used to follow the evolution of the particles formed in flames. These particle sizing techniques were chosen because of their sensitivity to detect inception particles, which have diameters, d < 5 mn, too small to be observed with typical particle measurement instrumentation. The size of the particles determined by AFM and DMA compares well with the size determined by in situ optical measurements, indicating that the interpretation of the UV-visible optical signal is quite good, and strongly showing the presence of d = 2-4 nm particles. UV-visible extinction measurements are also used to determine the concentration of d = 2-4 nm particles at the exhausts of practical combustion systems. A numerical model, able to reproduce the experimentally observed low coagulation rate of nanoparticles with respect to soot particles, is used to investigate the operating conditions in the combustion chamber and exhaust system for which 2-4 nm particles survive the exhaust or grow to larger sizes. Combustion generated nanoparticles are suspected to affect human and environmental health because of their affinity for water, small size, low rate of coagulation, and large surface area/weight ratio. The ability to isolate nanoparticles from soot particles in hydrosols collected from combustion may be useful for future analysis by a variety of techniques and toxicological assays.

In this paper, the d.c. and a.c. (ac) elec. transport properties of doped and undoped regioregular poly[3-(4-alkoxyphenyl)-thiophenes], where the alkoxy groups are O-(CH2)n-1CH3 with n = 1,4,6, and 8, have been investigated. The films have been synthesized by an exptl. procedure based on the oxidn. of 3-(4-alkoxyphenyl)-thiophenes with mol. oxygen in presence of VO(acac)2, as the catalyst. Unlike other examples reported in the literature, this approach allows obtaining well structured spin-coated films without the necessity of further processes, such as annealing or exposition to solvent vapors. D.c.-voltage measurements, performed in planar and transverse configuration on 1 m thick films, show both ohmic and space charge limited current behavior, at low and high applied fields, resp. Due to the film ordered structure, a significant elec. anisotropy was found. In order to deeply investigate the basic conduction mechanisms, ac measurements have been also carried out in the frequency range between 100 Hz and 100 kHz. Finally, d.c. and a.c. cond. temp. dependence is discussed in the framework of thermally activated hopping and tunneling models.