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Thermal energy deuterium beam scattering (TEDS) from Rh(110) surface is reported and compared to helium atom scattering (HAS). Unlike for He, we find quite strong D2 off-specular diffraction. The D2 diffraction intensities are fairly isotropic along the [001] and [110], reflecting the presence of a finite dissociation barrier in the potential energy surface (PES) rather than the anisotropic corrugation of the relevant Rh(110) surface electron density. Inelastic D2 scattering with strong J=0→2 kinetic-to-rotational energy conversion is also presented and discussed. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A new model potential for van der Waals atomic pairs is proposed and shown to be in excellent agreement with ab initio calculations and experimental potentials. The model allows the potential energy of a given pair to be estimated with good accuracy from ab initio density functional calculations of the free-atom electron densities. [ABSTRACT FROM AUTHOR]

Discusses the performance of the grating-crystal monochromator of the advanced line for overlayer, interface, and surface analysis (ALOISA) beamline at the Elettra Synchrotron. Use of a channel-cut silicon crystal dispersive element and a plane mirror-plane grating element; Spectral resolving power at the low energy range.

We present new measurements of He atom inelastic scattering from the (001) surface of Copper. Our results confirmed the recent data obtained in Gottingen and show that at large momentum transfer in the direction the intensity of the longitudinal resonance is larger than that of the Rayleigh wave. We interpret these results by evaluating the reflection coefficient in the Distorted Wave Born Approximation. By taking the He surface interaction potential as a sum of nonspherical pairwise potential we are able to explain quantitatively the behavior of the experimental spectra. [ABSTRACT FROM AUTHOR]

Lung infections are one of the leading causes of death worldwide, and this situation has been exacerbated by the emergence of COVID-19. Pre-clinical modelling of viral infections has relied on cell cultures that lack 3D structure and the context of lung extracellular matrices. Here, we propose a bioreactor-based, whole-organ lung model of viral infection. The bioreactor takes advantage of an automated system to achieve efficient decellularization of a whole rat lung, and recellularization of the scaffold using primary human bronchial cells. Automatization allowed for the dynamic culture of airway epithelial cells in a breathing-mimicking setup that led to an even distribution of lung epithelial cells throughout the distal regions. In the sealed bioreactor system, we demonstrate proof-of-concept for viral infection within the epithelialized lung by infecting primary human airway epithelial cells and subsequently injecting neutrophils. Moreover, to assess the possibility of drug screening in this model, we demonstrate the efficacy of the broad-spectrum antiviral remdesivir. This whole-organ scale lung infection model represents a step towards modelling viral infection of human cells in a 3D context, providing a powerful tool to investigate the mechanisms of the early stages of pathogenic infections and the development of effective treatment strategies for respiratory diseases., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

Complex anal fistulas (CAF) present a challenge in achieving healing while preserving anal sphincter function. This study aims to introduce a novel staged approach for CAF treatment, combining video-assisted anal fistula treatment (VAAFT), seton placement, and other staged approaches. Consecutive patients with CAF underwent the staged approach involving VAAFT and seton placement. Data on patient demographics, fistula characteristics, and operative findings were collected. Pre-operative work-up included clinical evaluation, endoanal ultrasonography (EAUS), and magnetic resonance imaging (MRI). Surgical techniques and outcomes were evaluated. Eighteen patients (median age 38 years) were included. Misplacement of a previously placed seton was observed in 64% of cases. VAAFT combined with seton placement achieved simplification and healing of secondary tracts in 66% of cases. Operative times significantly decreased across interventions. At a median follow-up of 14 months, complete healing was achieved in 2 patients, with 1 patient demonstrating persistence of the fistula. Post-operative complications were observed in 11% of patients, with no deterioration in continence. The staged approach combining VAAFT, seton placement, and staged procedures offers a potential solution for treating CAF. VAAFT provides diagnostic and therapeutic benefits, simplifying the fistula anatomy and optimizing seton placement. The approach allows subsequent procedures based on individual fistula characteristics., (© 2023. The Author(s).)

Background: Objective mobility goals for elderly hospitalised medical patients remain debated. We therefore studied steps parameters of elderly patients hospitalised for an acute illness, to determine goals for future interventional trials and medical practice., Methods: Observational study conducted from February to November 2018 in a medical ward of the Lausanne University Hospital, Switzerland. We measured the step parameters of consecutive medical patients aged ≥65 years admitted for an acute medical illness using a wrist accelerometer (Geneactiv). We also collected demographic, somatic and functional factors., Results: Overall, 187 inpatients had their step parameters (daily step count, walking cadence and bout duration) measured with accelerometers worn for a mean of 3.6 days (standard deviation [SD] 3.2). Elderly inpatients (81.5 years, SD 8.5) walked a median of 603 steps daily (interquartile range [IQR] 456-809), at a median cadence of 100 steps/minute (IQR 99-101) with median walking bouts of 33 seconds (IQR 27-37) and with 70% of the walking bouts lasting less than 30 seconds. Patients walking ≥600 steps were younger (80.4 years, SD 8.9 vs 82.8 years,SD 7.9, p = 0.050) and had a longer length of stay (7.8 days, SD 5.1 vs 6.1 days, SD 4.1, p = 0.011) than those walking <600 steps. Patients at high risk of bed sores walked less (564 steps, IQR 394-814 vs 626, IQR 526-840) than those with a lower risk of sores., Conclusion: During a hospitalisation for an acute medical illness, patients aged ≥65 years walk a mere 603 steps daily and most of the time for periods of less than 30 seconds. This information should be used to build up future interventional trials or to set mobility goals for patients hospitalised in Swiss hospitals.

Restoring pluripotency using chemical compounds alone would be a major step forward in developing clinical-grade pluripotent stem cells, but this has not yet been reported in human cells. We previously demonstrated that VPA&#95;AFS cells, human amniocytes cultivated with valproic acid (VPA) acquired functional pluripotency while remaining distinct from human embryonic stem cells (hESCs), questioning the relationship between the modulation of cell fate and molecular regulation of the pluripotency network. Here, we used single-cell analysis and functional assays to reveal that VPA treatment resulted in a homogeneous population of self-renewing non-transformed cells that fulfill the hallmarks of pluripotency, i.e., a short G1 phase, a dependence on glycolytic metabolism, expression of epigenetic modifications on histones 3 and 4, and reactivation of endogenous OCT4 and downstream targets at a lower level than that observed in hESCs. Mechanistic insights into the process of VPA-induced reprogramming revealed that it was dependent on OCT4 promoter activation, which was achieved independently of the PI3K (phosphatidylinositol 3-kinase)/AKT/mTOR (mammalian target of rapamycin) pathway or GSK3β inhibition but was concomitant with the presence of acetylated histones H3K9 and H3K56, which promote pluripotency. Our data identify, for the first time, the pluripotent transcriptional and molecular signature and metabolic status of human chemically induced pluripotent stem cells., (Copyright © 2017 The American Society of Gene and Cell Therapy. All rights reserved.)

The collision statistics of the energy dissipation of Auger and photoelectrons emitted from an amorphized Si(100) surface is studied by measuring the Si 2p photoelectron line as well as the first plasmon loss peak in coincidence with the Si-LVV Auger transition and the associated first plasmon loss. The Si 2p plasmon intensity decreases when measured in coincidence with the Si-LVV peak. If measured in coincidence with the Si-LVV plasmon the decrease is significantly smaller. The results agree quantitatively with calculations accounting for surface, volume, and intrinsic losses as well as elastic scattering in a random medium. In this way one can determine the average emission depth of individual electrons by means of Auger photoelectron coincidence spectroscopy, which therefore constitutes a unique tool to investigate interfaces at the nanoscale level.