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Neutron polarization analysis capability with a large scattering angle and momentum transfer coverage has not been widely implemented for the separation of coherent and incoherent quasi-elastic neutron scattering (QENS) spectra. A feasibility test for soft condensed matter applications was performed on the Multi-Axis Crystal Spectrometer (MACS) at the NIST Center for Neutron Research (NCNR). This capability benefitted from the high flux wide angle polarization analysis capability recently developed on MACS for hard condensed matter investigations. The experimental procedure is thoroughly described on how to take data and perform polarization efficiency correction before further data analysis is done. This capability was employed to unambiguously separate the coherent and incoherent signal from the QENS spectra for the investigation of both the collective and the single particle dynamics in partially deuterated (CH 3 OD, D 99.5% purity) methanol. By studying a Q range encompassing the prepeak position, it was possible to directly measure the dynamics of the h-bonding associates which originate the prepeak signal, without contamination from the incoherent scattering, in spite of the relative weakness of the coherent scattering. [ABSTRACT FROM AUTHOR]

After linear hydrophilic polymers with a short hydrophobic sticker have been proven to be highly suitable as efficiency boosters in microemulsions, a whole set of asymmetric polymers was studied in more detail. Sticker polymers with two hydrophilic polymeric arms, hydrophobic polymers with ionic stickers, and a Y-shaped tri-arm-polymer were studied for their high surface activity. While low asymmetry of the Y-shaped polymer resulted in very similar dependence as a diblock copolymer, the highly asymmetric polymers showed a renormalized behavior of the bending rigidity coming from preferential accretion of the polymer at the membrane. The experimental evidence for the accretion of the polymer according to the preferential membrane bending is reported here for the first time. Furthermore, the isolated, diffuse counter ion clouds of the ionic sticker polymers act in a way similar to that of a polymer anchored at the membrane. All asymmetric polymers are highly suitable as efficiency boosters in microemulsions. [ABSTRACT FROM AUTHOR]

The molecular-scale dynamic properties of the room temperature ionic liquid (RTIL) 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, or [C4mim+][Tf2N-], confined in hierarchical microporous-mesoporous carbon, were investigated using neutron spin echo (NSE) and molecular dynamics (MD) simulations. Both NSE and MD reveal pronounced slowing of the overall collective dynamics, including the presence of an immobilized fraction of RTIL at the pore wall, on the time scales of these approaches. A fraction of the dynamics, corresponding to RTIL inside 0.75nm micropores located along the mesopore surfaces, are faster than those of RTIL in direct contact with the walls of 5.8nm and 7.8nm cylindrical mesopores. This behavior is ascribed to the near-surface confined-ion density fluctuations resulting from the ion-ion and ion-wall interactions between the micropores and mesopores as well as their confinement geometries. Strong micropore-RTIL interactions result in less-coordinated RTIL within the micropores than in the bulk fluid. Increasing temperature from 296K to 353K reduces the immobilized RTIL fraction and results in nearly an order of magnitude increase in the RTIL dynamics. The observed interfacial phenomena underscore the importance of tailoring the surface properties of porous carbons to achieve desirable electrolyte dynamic behavior, since this impacts the performance in applications such as electrical energy storage devices. [ABSTRACT FROM AUTHOR]

Despite Tocilizumab is now recognized as a concrete therapeutic option in patients with severe SARS-CoV-2 related respiratory failure, literature lacks about factors influencing the response to it in this context. Therefore, the aim of our study was to provide evidence about predictors of poor outcome in Tocilizumab treated patients in the real-world practice. We retrospectively analyzed clinical, laboratory and chest computer tomography (CCT) data of patients firstly admitted in non Intensive Care Units (ICU) and suffering from severe respiratory failure, who were treated with the IL-6 antagonist Tocilizumab. We compared patients who died and/or required admission to ICU with oro-tracheal intubation (OTI) with those who did not. Two hundreds and eighty-seven patients (29.9% females) with mean age ± SD 64.1 ± 12.6 years were the study population. In-hospital mortality was 18.8%, while the composite endpoint in-hospital mortality and/or ICU admission with OTI occurred in 23.7%. At univariate analysis, patients who died and/or were admitted to ICU with OTI were significantly older and co-morbid, had significantly higher values of creatinine, C-reactive protein (CRP) and procalcitonin and lower lymphocytes count, PaO2/FiO2 ratio (P/F) and room air pulsossimetry oxygen saturation (RAO 2 S) at hospital admission. Computed tomography ground glass opacities (CT-GGO) involving the pulmonary surface ≥ 50% were found in 55.4% of patients who died and/or were admitted to ICU with OTI and in 21.5% of patients who did not (p=0.0001). At multivariate analysis, age ≥ 65 years (OR 17.3, 95% CI: 3.7-81.0), procalcitonin ≥ 0.14 (OR 9.9, 95%CI: 1.7-56.1), RAO 2 S ≤ 90% (OR 4.6, 95%CI: 1.2-17.0) and CCT-GGO involvement ≥ 50% (OR 5.1, 95%CI: 1.2-21.0) were independent risk factors associated with death and/or ICU admission with OTI. Tocilizumab has shown to improve outcome in patients with severe respiratory failure associated to SARS-CoV-2 related pneumonia. In our multicentre study focusing on Tocilizumab treated severe COVID-19 patients, age ≥ 65 years, procalcitonin ≥ 0.14 ng/mL, RAO 2 S ≤ 90% and CCT-GGO involvement ≥ 50% were independent factors associated with poor outcome. [ABSTRACT FROM AUTHOR]

Highlights: [•] We examined a Tb based single molecule magnet by ac susceptibility and QENS. [•] We found two distinct magnetic relaxations in a wide time range from 0.1ms to 1ps. [•] The slower relaxation corresponds to the thermally activated tunneling process. [•] The faster one couples with the motion of H atoms around the magnetic ions. [•] The two relaxations exhibit a crossover around 100ns. [ABSTRACT FROM AUTHOR]

The diffusion dynamics of hydrogen in bulk and nanocrystalline palladium has been examined using quasielastic neutron scattering (QENS). With respect to bulk PdH0.73, two relaxation processes were found. For both processes, the variation of the relaxation times with momentum transfer was well reproduced by a model of jump diffusion between adjacent octahedral sites. Upon cooling the fast relaxation fraction decreases. The result suggests that the slow relaxation corresponds to jumps between the ground states and the fast one between excited states. In nanocrystalline PdH0.47 with a size of 8 nm, we found a fast diffusion process with a smaller activation energy in addition to the one observed in the bulk sample. This process could be due to the motion of hydrogen atoms in the subsurface region where the potential energy surface is substantially modified by surface strain/distortion effects. [ABSTRACT FROM AUTHOR]

The Rouse dynamics of polymer chains in model nanocomposite polyethylene oxide/silica nanoparticles (NPs) was investigated using quasielastic neutron scattering. The apparent Rouse rate of the polymer chains decreases as the particle loading increases. However, there is no evidence of an immobile segment population on the probed time scale of tens of ps. The slowing down of the dynamics is interpreted in terms of modified Rouse models for the chains in the NP interphase region. Thus, two chain populations, one bulk-like and the other characterized by a suppression of Rouse modes, are identified. The spatial extent of the interphase region is estimated to be about twice the adsorbed layer thickness, or ≈2 nm. These findings provide a detailed description of the suppression of the chain dynamics on the surface of NPs. These results are relevant insights on surface effects and confinement and provide a foundation for the understanding of the rheological properties of polymer nanocomposites with well-dispersed NPs.

Dynamic neutron scattering probes unique nanoscale dynamics via measurement of energy exchanged between a sample and the neutrons. The two spectrometers that investigate processes with characteristic times around a nanosecond are backscattering (BS) and neutron spin-echo (NSE). We present a new method for measuring dynamics using an oscillating cosine-like energy-distribution neutron-package at the sample and measure solely the portion scattered into the elastic line. This portion corresponds to elastically scattered neutrons and, in addition, inelastic components that are scattered with a probability directly proportional to the cosine Fourier-coefficients of the exchanged-energy spectrum. The counts at the detector thus correspond to the van Hove intermediate scattering function. We denote this new method as "Fourier transform neutron scattering" (FTNS), it being broadly analogous to IR and Raman spectroscopies. Here, the realization of such a concept is investigated using an oscillating incident beam produced via a precession method and a secondary spectrometer identical to a BS instrument using crystal analyzers. The instrument is denoted "Modulated Intensity with Diffraction Analysis Spectrometer" (MIDAS). However, simpler approaches, e.g., choppers, may also be used for an FTNS instrument. The theory behind MIDAS is presented, supported by numerical calculations and in silico experiments. Finally, we present a Monte Carlo simulation to compare BS and MIDAS spectrometers. This shows that MIDAS has almost 100 times more incident flux than standard BS, but due to the better signal-to-noise ratio of BS, the final information acquisition rate gain of MIDAS is approximately a factor of 2., (© 2024 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).)

Background: eosinophilic granulomatosis with polyangiitis (EGPA) is a rare multisystem inflammatory disease characterized by asthma, eosinophilia and granulomatous or vasculitic involvement of various organs. While the eye is uncommonly affected in patients with EGPA, multiple ophthalmic manifestations have been reported, which can result in serious visual impairment without timely treatment., Case Report: we report the case of a 79-year-old woman with a history of asthma and nasal polyps who presented with low-grade fever, mild alteration of mental status, and fatigue. Chest X-ray revealed bilateral interstitial infiltrates. Lab tests showed elevated C-reactive protein level and eosinophilia (eosinophil count, 4.6 x10 9 cells/l); blood cultures and parasitological examination of stools tested negative. Four days after presentation, the patient reported sudden and severe blurring of vision in her left eye. Ophthalmological examination revealed bilateral swollen optic disc and visual field loss, more severe in the left eye. A diagnosis of EGPA complicated by arteritic anterior ischaemic optic neuropathy (A-AION) was proposed, while an alternative or concurrent diagnosis of giant cell arteritis was ruled out based on clinical picture. Immunosuppressive treatment with high-dose intravenous glucocorticoids was promptly started. The patient's visual defect did not improve; however, two months later, no worsening was registered on ophthalmic reassessment., Conclusions: A-AION is an infrequent but severe manifestation of EGPA, requiring prompt diagnosis and emergency-level glucocorticoid therapy to prevent any further vision loss. Disease awareness and a multidisciplinary approach are crucial to expedite diagnostic work-up and effective management of EGPA-related ocular complications., Learning Points: Arteritic ischaemic optical neuropathy is a potential cause of sudden and severe visual loss in eosinophilic granulomatosis with polyangiitis (EGPA) patients.Visual loss due to arteritic ischaemic optical neuropathy is rarely reversible; however, a timely glucocorticoid treatment may prevent further progression of visual impairment.Multidisciplinary approach is crucial to expedite diagnostic work-up and effective management of EGPA patients with ocular complications., Competing Interests: Conflicts of Interests: The Authors declare that there are no competing interests., (© EFIM 2024.)

Background: Calprotectin (S100A8/A9) has been identified as a biomarker that can aid in predicting the severity of disease in COVID-19 patients. This study aims to evaluate the correlation between levels of circulating calprotectin (cCP) and the severity of COVID-19., Methods: Sera from 245 COVID-19 patients and 110 apparently healthy individuals were tested for calprotectin levels using a chemiluminescent immunoassay (Inova Diagnostics). Intensive care unit (ICU) admission and type of respiratory support administered were used as indicators of disease severity, and their correlation with calprotectin levels was assessed., Results: Samples from patients in the ICU had a median calprotectin concentration of 11.6 µg/ml as compared to 3.5 µg/ml from COVID-19 patients who were not in the ICU. The median calprotectin concentration in a cohort of healthy individuals collected before the COVID-19 pandemic was 3.0 µg/ml (95% CI: 2.820-2.969 µg/ml). Patients requiring a Venturi mask, continuous positive airway pressure, or orotracheal intubation all had significantly higher values of calprotectin than controls, with the increase of cCP levels proportional to the increasing need of respiratory support., Conclusion: Calprotectin levels in serum correlate well with disease severity and represent a promising serological biomarker for the risk assessment of COVID-19 patients., (© 2022 Wiley Periodicals LLC.)

We investigate the structure and dynamics of unentangled semidilute solutions of sodium polystyrenesulfonate (NaPSS) using small-angle neutron scattering (SANS) and neutron spin-echo (NSE) spectroscopy. The effects of electrostatic interactions and chain structure are examined as a function of ionic strength and polymer concentration, respectively. The SANS profiles exhibit a characteristic structural peak, signature of polyelectrolyte solutions, that can be fit with a combination of a semiflexible chain with excluded volume interactions form factor and a polymer reference interaction site model (PRISM) structure factor. We confirm that electrostatic interactions vary with ionic strength across solutions with similar geometries. The segmental relaxations from NSE deviate from theoretical predictions from Zimm and exhibit two scaling behaviors, with the crossover between the two regimes taking place around the characteristic structural peak. The chain dynamics are suppressed across the length scale of the correlation blob, and inversely related to the structure factor. These observations suggest that the highly correlated nature of polyelectrolytes presents an additional energy barrier that leads to de Gennes narrowing behavior.

The relaxation behavior of glass formers exhibits spatial heterogeneity and dramatically changes upon cooling towards the glass transition. However, the underlying mechanisms of the dynamics at different microscopic length scales are not fully understood. Employing the recently developed wide-angle neutron spin-echo spectroscopy technique, we measured the Q-dependent coherent intermediate scattering function of a prototypical ionic glass former Ca 0.4 K 0.6 (NO 3 ) 1.4 , in the highly viscous liquid state. In contrast to the structure modulated dynamics for Q < 2.4 Å -1 , i.e., at and below the structure factor main peak, for Q > 2.4 Å -1 , beyond the first minimum above the structure factor main peak, the stretching exponent exhibits no temperature dependence and concomitantly the relaxation time shows smaller deviations from Arrhenius behavior. This finding indicates a change in the dominant relaxation mechanisms around a characteristic length of 2π/(2.4 Å -1 ) ≈ 2.6 Å, below which the relaxation process exhibits a temperature independent distribution and more Arrhenius-like behavior., (© 2022. The Author(s).)

Purpose: During a follow-up program of patients admitted for COVID-19 at our non-ICU Unit, we found that 37% of them had decreased diffusing lung capacity for carbon monoxide (DLCO) 3-6 months after discharge. This prospective observational study aimed to evaluate the evolution of changes in DLCO and respiratory symptoms at the 1-year follow-up visit., Methods: Seventeen (mean age 71 years; 8 males) of 19 eligible patients (DLCO < 80% of predicted at the 3-6 months follow-up visit) completed the 1-year follow-up visit. One patient refused to participate and 1 patient had died 3 months earlier from myocardial infarction. The visit included a self-reported structured questionnaire, physical exam, blood tests, ECG, and spirometry with DLCO., Results: Mean DLCO was significantly improved at the 1-year visit (from 64% of predicted at 3-6 months to 74% of predicted at 1 year; P = 0.003). A clinically significant increase in DLCO (10% or greater) was observed in 11 patients (65%) with complete normalization (> 80% of predicted) in 6 (35%); in the other 6 (35%) it remained unchanged. The prevalence of exertional dyspnea (65-35%, P = 0.17), cough (24-18%, P = 1), and fatigue (76-35%, P = 0.04) decreased at the 1-year visit., Conclusion: These results suggest that DLCO and respiratory symptoms tend to normalize or improve 1 year after hospitalization for COVID-19 in most patients. However, there is also a non-negligible number of patients (about one-third) in whom respiratory changes persist and will need prolonged follow-up., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany.)

The dynamics of molecular associates in a methanol/water mixture was investigated using quasielastic neutron scattering. By measuring the signal from four methanol/water samples differing only by their isotopic composition, the relative motion of the water to methanol molecules, i.e. their mutual dynamics, was determined at the nanoscale. The thus obtained nanoscopic mutual diffusion coefficient signals a significantly slower process than the single particle diffusion of either methanol or water in the system as well as their macroscopic mutual diffusion. The data do not provide any indication of microsegregation in this preeminent alcohol/water mixture; however, they do indicate the existence of long lived but dynamic molecular associates of water and methanol molecules. Analysis of the structural relaxation shows that the lifetime of molecular association through hydrogen bonding determines the fact that viscosity of the mixtures at intermediate concentrations is higher than that of both pure components.

Neutron scattering methods were employed to study the microscopic structure and dynamics of Bio Crude Oils (BCOs) and their lignin fractions. The structure of the carbonaceous aggregates was investigated using Small Angle Neutron Scattering to reveal a fractal hierarchy as well as a growth of the aggregates as the aging of the BCO proceeds. Elastic Neutron Scattering measurements indicate that BCO liquid phase, comprised of water and other hydrogenated molecular liquids, is in a state of extreme confinement. Quasi-Elastic Neutron Scattering yields information on the molecular motions, indicating that long range translational diffusion is suppressed and only localized dynamics take place on the tens of picosecond time range. The obtained results provide quantitative information on the molecular activity, as aging proceed, in these reactive materials of relevance as potential renewable energy sources., 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 © 2021 Bonini, Fratini and Faraone.)

Background: The COVID-19 pandemic has put a strain on health systems. Predictors of adverse outcomes need to be investigated to properly manage COVID-19 patients. The Braden Scale (BS), commonly used for the assessment of pressure ulcer risk, has recently been proposed to identify frailty., Objective: To investigate the predictive utility of the BS for prediction of in-hospital mortality in a cohort of COVID-19 patients admitted to non-ICU wards., Methods: We conducted a retrospective single-center cohort study evaluating all patients with SARS-CoV-2 infection consecutively admitted over a 2-month period (from March 6 to May 7, 2020) to the COVID-19 general wards of our institution. Demographic, clinical, and nursing assessment data, including admission BS, were extracted from electronic medical records. Univariable and multivariable logistic regression models were used to explore the association between the BS score and in-hospital death., Results: Braden Scale was assessed in 146 patients (mean age 74.7 years; 52% males). On admission, 46 had a BS ≤ 15, and 100 patients had a BS > 15. Mortality among patients with BS ≤ 15 was significantly higher than in patients with BS > 15 (45.7% vs. 16%; p < .001). On multivariable regression analysis, adjusting for potentials confounders (age, Barthel scale, chronic kidney disease, atrial fibrillation, and hypertension), the admission BS remained inversely associated with the risk of in-hospital mortality (OR = 0.76; 95% CI [0.60, 0.96]; p = .020)., Linking Evidence to Action: Admission BS could be used as a simple bedside predictive tool able to early identify non-ICU COVID-19 patients with poor prognosis who might benefit from specific and timely interventions., (© 2021 Sigma Theta Tau International.)

Background: Nursing home (NH) residents have been dramatically affected by COVID-19, with extremely high rates of hospitalization and mortality., Aims: To describe the features and impact of an assistance model involving an intermediate care mobile medical specialist team (GIROT, Gruppo Intervento Rapido Ospedale Territorio) aimed at delivering "hospital-at-nursing home" care to NH residents with COVID-19 in Florence, Italy., Methods: The GIROT activity was set-up during the first wave of the pandemic (W1, March-April 2020) and became a structured healthcare model during the second (W2, October 2020-January 2021). The activity involved (1) infection transmission control among NHs residents and staff, (2) comprehensive geriatric assessment including prognostication and geriatric syndromes management, (3) on-site diagnostic assessment and protocol-based treatment of COVID-19, (4) supply of nursing personnel to understaffed NHs. To estimate the impact of the GIROT intervention, we reported hospitalization and infection lethality rates recorded in SARS-CoV-2-positive NH residents during W1 and W2., Results: The GIROT activity involved 21 NHs (1159 residents) and 43 NHs (2448 residents) during W1 and W2, respectively. The percentage of infected residents was higher in W2 than in W1 (64.5% vs. 38.8%), while both hospitalization and lethality rates significantly decreased in W2 compared to W1 (10.1% vs 58.2% and 23.4% vs 31.1%, respectively)., Discussion: Potentiating on-site care in the NHs paralleled a decrease of hospital admissions with no increase of lethality., Conclusions: An innovative "hospital-at-nursing home" patient-centred care model based on comprehensive geriatric assessment may provide a valuable contribution in fighting COVID-19 in NH residents., (© 2021. The Author(s).)

Purpose: Few data are currently available on persistent symptoms and late organ damage in patients who have suffered from COVID-19. This prospective study aimed to evaluate the results of a follow-up program for patients discharged from a nonintensive COVID-19 ward., Methods: 3-6 months after hospital discharge, 59 of 105 COVID-19 patients (31 males, aged 68.2 ± 12.8 years) were recruited in the study. Forty-six patients were excluded because of nontraceability, refusal, or inability to provide informed consent. The follow-up consisted of anamnesis (including a structured questionnaire), physical examination, blood tests, ECG, lower limb compression venous ultrasound (US), thoracic US, and spirometry with diffusion lung capacity for carbon monoxide (DLCO)., Results: 22% of patients reported no residual symptoms, 28.8% 1 or 2 symptoms and 49.2% 3 or more symptoms. The most frequently symptoms were fatigue, exertional dyspnea, insomnia, and anxiety. Among the inflammatory and coagulation parameters, only the median value of fibrinogen was slightly above normal. A deep vein thrombosis was detected in 1 patient (1.7%). Thoracic US detected mild pulmonary changes in 15 patients (25.4%), 10 of which reported exertional dyspnea. DLCO was mildly or moderately reduced in 19 patients (37.2%), 13 of which complained of exertional dyspnea., Conclusion: These results highlight that a substantial percentage of COVID-19 patients (77.8%) continue to complain of symptoms 3-6 months after hospital discharge. Exertional dyspnea was significantly associated with the persistence of lung US abnormalities and diffusing capacity alterations. Extended follow-up is required to assess the long-term evolution of postacute sequelae of COVID-19., (© 2021. Springer-Verlag GmbH Germany, part of Springer Nature.)

Membrane viscosity is a fundamental property that controls molecular transport and structural rearrangements in lipid membranes. Given its importance in many cell processes, various experimental and computational methods have been developed to measure the membrane viscosity, yet the estimated values depend highly on the method and vary by orders of magnitude. Here we investigate the molecular origins of membrane viscosity by measuring the nanoscale dynamics of the lipid acyl tails using x-ray and neutron spectroscopy techniques. The results show that the membrane viscosity can be estimated from the structural relaxation times of the lipid tails.

The role of noninvasive positive pressure ventilation (NIPPV) in COVID-19 patients with acute hypoxemic respiratory failure (AHRF) is uncertain, as no direct evidence exists to support NIPPV use in such patients. We retrospectively assessed the effectiveness and safety of NIPPV in a cohort of COVID-19 patients consecutively admitted to the COVID-19 general wards of a medium-size Italian hospital, from March 6 to May 7, 2020. Healthcare workers (HCWs) caring for COVID-19 patients were monitored, undergoing nasopharyngeal swab for SARS-CoV-2 in case of onset of COVID-19 symptoms, and periodic SARS-CoV-2 screening serology. Overall, 50 patients (mean age 74.6 years) received NIPPV, of which 22 (44%) were successfully weaned, avoiding endotracheal intubation (ETI) and AHRF-related death. Due to limited life expectancy, 25 (50%) of 50 NIPPV-treated patients received a "do not intubate" (DNI) order. Among these, only 6 (24%) were weaned from NIPPV. Of the remaining 25 NIPPV-treated patients without treatment limitations, 16 (64%) were successfully weaned, 9 (36%) underwent delayed ETI and, of these, 3 (33.3%) died. NIPPV success was predicted by the use of corticosteroids (OR 15.4, CI 1.79-132.57, p 0.013) and the increase in the PaO 2 /FiO 2 ratio measured 24-48 h after NIPPV initiation (OR 1.02, CI 1-1.03, p 0.015), while it was inversely correlated with the presence of a DNI order (OR 0.03, CI 0.001-0.57, p 0.020). During the study period, 2 of 124 (1.6%) HCWs caring for COVID-19 patients were diagnosed with SARS-CoV-2 infection. Apart from patients with limited life expectancy, NIPPV was effective in a substantially high percentage of patients with COVID-19-associated AHRF. The risk of SARS-CoV-2 infection among HCWs was low., (© 2020. Società Italiana di Medicina Interna (SIMI).)

The elastic properties of the cellular lipid membrane play a crucial role for life. Their alteration can lead to cell malfunction, and in turn, being able to control them holds the promise of effective therapeutic and diagnostic approaches. In this context, due to their proven strong interaction with lipid bilayers, ionic liquids (ILs)-a vast class of organic electrolytes-may play an important role. This work focuses on the effect of the model imidazolium-IL [bmim][Cl] on the bending modulus of DMPC lipid vesicles, a basic model of cellular lipid membranes. Here, by combining small-angle neutron scattering and neutron spin-echo spectroscopy, we show that the IL, dispersed at low concentrations at the bilayer-water interface, (i) diffuses into the lipid region, accounting for five IL-cations for every 11 lipids, and (ii) causes an increase of the lipid bilayer bending modulus, up to 60% compared to the neat lipid bilayer at 40 °C.

2-Propanol was investigated, in both the liquid and supercooled states, as a model system to study how hydrogen bonds affect the structural relaxation and the dynamics of mesoscale structures, of approximately several Ångstroms, employing static and quasi-elastic neutron scattering and molecular dynamics simulation. Dynamic neutron scattering measurements were performed over an exchanged wave-vector range encompassing the pre-peak, indicative of the presence of H-bonding associates, and the main peak. The dynamics observed at the pre-peak is associated with the formation and disaggregation of the H-bonded associates and is measured to be at least one order of magnitude slower than the dynamics at the main peak, which is identified as the structural relaxation. The measurements indicate that the macroscopic shear viscosity has a similar temperature dependence as the dynamics of the H-bonded associates, which highlights the important role played by these structures, together with the structural relaxation, in defining the macroscopic rheological properties of the system. Importantly, the characteristic relaxation time at the pre-peak follows an Arrhenius temperature dependence whereas at the main peak it exhibits a non-Arrhenius behavior on approaching the supercooled state. The origin of this differing behavior is attributed to an increased structuring of the hydrophobic domains of 2-propanol accommodating a more and more encompassing H-bond network, and a consequent set in of dynamic cooperativity.

Background: Few data are available on the validity of "Sepsis-3" criteria in identifying patients with sepsis in internal medicine wards (IMWs). Real-life data about this topic and on the prevalence of sepsis in IMWs could be useful for improving hospital organization., Objectives: To assess the validity of "Sepsis-3" criteria in identifying patients with community-onset sepsis in IMWs. Secondary objectives: to evaluate the prevalence of these patients in IMWs and to compare "Sepsis-3" and "Sepsis-1" criteria., Methods: Multicenter, prospective, observational, cohort study, carried out in 22 IMWs of Tuscany (Italy). All patients admitted to each of the study centers over a period of 21-31 days were evaluated within 48 hours; those with clinical signs of infection were enrolled. The main outcome was in-hospital mortality., Results: 2,839 patients were evaluated and 938 (33%) met the inclusion criteria. Patients with sepsis diagnosed according to "Sepsis-3" were 522, representing 55.6% of patients with infection and 18.4% of all patients hospitalized; they were older than those without sepsis (79.4±12.5 vs 74.6±15.2 years, p<0.001). In-hospital mortality was significantly higher in patients with sepsis compared to others (13.8% vs 4.6%; p<0.001). "Sepsis-3" criteria showed greater predictive validity for in-hospital mortality than "Sepsis-1" criteria (AUROC=0.71; 95%CI, 0.66-0.77 vs 0.60; 95%CI 0.54-0.66; p=0.0038)., Conclusions: "Sepsis-3" criteria are able to identify patients with community-onset sepsis in IMWs, whose prevalence and in-hospital mortality are remarkably high. Medical departments should adapt their organization to the needs for care of these complex patients., (Copyright © 2021. Published by Elsevier B.V.)

Using neutron spin-echo spectroscopy, we studied the microscopic structural relaxation of a prototypical network ionic liquid ZnCl 2 at the structure factor primary peak and prepeak. The results show that the relaxation at the primary peak is faster than the prepeak and that the activation energy is ∼33% higher. A stretched exponential relaxation is observed even at temperatures well-above the melting point T m . Surprisingly, the stretching exponent shows a rapid increase upon cooling, especially at the primary peak, where it changes from a stretched exponential to a simple exponential on approaching the T m . These results suggest that the appearance of glassy dynamics typical of the supercooled state even in the equilibrium liquid state of ZnCl 2 as well as the difference of activation energy at the two investigated length scales are related to the formation of a network structure on cooling.

The structural relaxation in water solutions of kosmotrope (structure maker) and chaotrope (structure breaker) salts, namely sodium chloride, potassium chloride, and cesium chloride, were studied through quasielastic neutron scattering measurements. We found that the collective dynamics relaxation time at the structure factor peak obtained using heavy water solutions shows a distinctively different behavior in the kosmotrope as opposed to the chaotrope solutions, increasing with the salt concentration in the former and decreasing in the latter. In both cases the trends are proportional to the concentration dependence of the relative viscosity of the solutions. These results indicate that kosmotropes and chaotropes influence the solution's viscosity by impacting in opposite ways the hydrogen bond network of water, strengthening it in one case and softening it in the other.

Purpose: Carbapenem consumption is a major driver for selection and spread of carbapenem-resistant Enterobacterales (CRE). We assessed the impact of a carbapenem-focused multimodal antimicrobial stewardship program (ASP) in the internal medicine unit of a medium-size acute-care hospital., Methods: We compared the percentage of inappropriate carbapenem prescriptions and the proportion of carbapenem treated patients registered in a 12-month pre-intervention and in a 24-month post-intervention period by using an interrupted time series analysis. The consumption of carbapenems, expressed in defined daily doses (DDD), was also assessed. As a secondary objective, the incidence of infections by carbapenem-resistant Klebsiella pneumoniae (CRKP) and the percentage of CRKP invasive isolates in the same time periods were compared., Results: After the ASP intervention, the mean monthly percentage of inappropriate carbapenem prescriptions dropped from 59% to 25%, and the mean monthly proportion of carbapenem treated patients decreased from 3% to 1%. The interrupted time series analysis confirmed a significant decrease in the percentage of inappropriate carbapenem prescriptions (-41.6%, p = 0.0262) and in the proportion of carbapenem treated patients (-2.1%, p < 0.0001). Carbapenem consumption decreased from 5.2 to 1.6 DDD x 100 patient-days. The incidence of CRKP infections remained unchanged (29.1 × 100,000 patient-days vs 28.9 × 100,000 patient-days, p = 0.9864) and the percentage of CRKP invasive isolates decreased, though not significantly, from 36.4% to 13.3% (p = 0.3478)., Conclusions: The implementation of a carbapenem-focused ASP was effective at limiting the inappropriate use of carbapenems and was associated with a significant decrease in carbapenem consumption. Such effects were sustained during a 24-month post-intervention period., Competing Interests: Declaration of Competing Interest On behalf of all authors, the corresponding author states that there are no known conflicts of interest associated with this publication and there has been no financial support for this work that could have influenced its outcome., (Copyright © 2020 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.)

Polymer chain dynamics of a nanostructured block copolymer electrolyte, polystyrene- block -poly(ethylene oxide) (SEO) mixed with lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) salt, are investigated by neutron spin echo (NSE) spectroscopy on the 0.1-100 ns time scale and analyzed using the Rouse model at short times ( t ≤ 10 ns) and the reptation tube model at long times ( t ≥ 50 ns). In the Rouse regime, the monomeric friction coefficient increases with increasing salt concentration, as seen previously in homopolymer electrolytes. In the reptation regime, the tube diameters, which represent entanglement constraints, decrease with increasing salt concentration. The normalized longest molecular relaxation time, calculated from the NSE results, increases with increasing salt concentration. We argue that quantifying chain motion in the presence of ions is essential for predicting the behavior of polymer-electrolyte-based batteries operating at large currents.

The purpose of this prospective observational study was to evaluate the yield and clinical impact of blood cultures in a 78-bed Internal Medicine ward of a medium-sized Italian acute care hospital. During a two-month study period, 154 (mean age: 75.2 ++ 12.2 years; 94 males) out of 620 (24.8%) hospitalized patients underwent 174 blood cultures and were enrolled in the study. The rate of true-positive cultures was 11.5% (20/174) and the rate of false-positive (contaminants) was 5.7% (10/174). A total of 23 microorganisms (5 multidrug resistant strains), most frequently Escherichia coli (n = 10), Klebsiella pneumoniae (n = 3) and Staphylococcus aureus (n = 3), were isolated. The positivity rate was significantly higher in patients with urinary tract infection (31%) and abdomen infection (26.1%) than in patients with pneumonia (4.9%; p<0.01). Although the positivity rate in patients exposed to antibiotics was lower than in those not exposed, the difference was not statistically significant. Therapy changes due to blood culture positivity were observed in 7.1% of the patients overall. In-hospital death was observed in nine of the 136 patients with negative blood cultures (6.6%) and in none of the 18 patients with positive blood cultures. These results indicate that the yield and clinical impact of blood cultures is quite low in patients admitted to an Internal Medicine ward and suggest the need to improve the adequacy of the indications to perform the test.

Understanding the dynamics of soft colloids, such as star polymers, dendrimers, and microgels, is of scientific and practical importance. It is known that the excluded volume effect plays a key role in colloidal dynamics. Here, we propose a condition of compressibility equivalence that provides a simple method to experimentally evaluate the excluded volume of soft colloids from a thermodynamic view. We apply this condition to survey the dynamics of a series of star polymer dispersions. It is found that, as the concentration increases, the slowing of the long-time self-diffusivity of the star polymer, normalized by the short-time self-diffusivity, can be mapped onto the hard-sphere behavior. This phenomenon reveals the dynamic equivalence between soft colloids and hard spheres, despite the apparent complexity of the interparticle interaction of the soft colloids. The methods for measuring the osmotic compressibility and the self-diffusivities of soft colloidal dispersions are also presented.

Polymer mobility near nanoparticle surfaces has been extensively discussed; however, direct experimental observation in the nanocomposite melts has been a difficult task. Here, by taking advantage of large dynamical asymmetry between the miscible matrix and surface-bound polymers, we highlighted their interphases and studied the resulting effect on the nanoparticle relaxation using X-ray photon correlation spectroscopy. The local mobility gradient is signified by an unprecedented increase in the relaxation time at length scales on the order of polymer radius of gyration. The effect is accompanied by a transition from simple diffusive to subdiffusive behavior in accord with viscous and entangled dynamics of polymers in the matrix and in the interphase, respectively. Our results demonstrate that the nanoparticle-induced polymer mobility changes in the interphases of nanocomposite melts can be extracted from the length-scale-dependent slow particle motion.

The single particle dynamics of water confined within two ordered mesoporous carbon matrices was investigated in the temperature range from 290 K to 170 K by quasielastic neutron scattering using three high resolution neutron spectrometers. Thus, it was possible to investigate the mobility of water confined in model hydrophobic cavities at the nanoscale. Models developed for the nanoscale dynamics of supercooled water and water confined within hydrophilic matrices were able to describe the collected data but remarkable differences with analogous silica confined matrices were observed in these carbon samples. A significant fraction of the water molecules was immobile on the nanosecond timescale, even at room temperature. As the temperature was lowered, the mobility of the water molecules slowed down, but the strongly non-Arrhenius behavior observed in bulk water and for fully hydrated hydrophilic confinement was absent, which indicates frustration of the hydrogen bond network formation. The obtained results were relevant for applications of mesoporous carbon materials.

To investigate the dynamical properties of the novel hybrid compound, lithium benzimidazolate-borohydride Li 2 (bIm)BH 4 (where bIm denotes a benzimidazolate anion, C 7 N 2 H 5 - ), we have used a set of complementary techniques: neutron powder diffraction, ab initio density functional theory calculations, neutron vibrational spectroscopy, nuclear magnetic resonance, neutron spin echo, and quasi-elastic neutron scattering. Our measurements performed over the temperature range from 1.5 to 385 K have revealed the exceptionally fast low-temperature reorientational motion of BH 4 - anions. This motion is facilitated by the unusual coordination of tetrahedral BH 4 - anions in Li 2 (bIm)BH 4 : each anion has one of its H atoms anchored within a nearly square hollow formed by four coplanar Li + cations, while the remaining -BH 3 fragment extends into a relatively open space, being only loosely coordinated to other atoms. As a result, the energy barriers for reorientations of this fragment around the anchored B-H bond axis are very small, and at low temperatures, this motion can be described as rotational tunneling. The tunnel splitting derived from the neutron spin echo measurements at 3.6 K is 0.43(2) μ eV. With increasing temperature, we have observed a gradual transition from the regime of low-temperature quantum dynamics to the regime of classical thermally activated jump reorientations. The jump rate of the uniaxial 3-fold reorientations reaches 5 × 10 11 s -1 at 80 K. Nearer room temperature and above, both nuclear magnetic resonance and quasielastic neutron scattering measurements have revealed the second process of BH 4 - reorientations characterized by the activation energy of 261 meV. This process is several orders of magnitude slower than the uniaxial 3-fold reorientations; the corresponding jump rate reaches ~7 × 10 8 s -1 at 300 K., Competing Interests: The authors declare no competing financial interest.

Carbon nanotube (CNT) grafted glass fiber reinforced epoxy nanocomposites (GFRP) present a range of stiffnesses (MPa to GPa) and length scales ( μ m to nm) at the fiber-matrix interface. The contribution of functionalized CNT networks to the local and bulk polymer dynamics is studied here by using a combination of torsion dynamical mechanical thermal analysis (DMTA), positron annihilation lifetime spectroscopy (PALS), and neutron scattering (NS) measurements. DMTA measurements highlight a reduction in the storage modulus ( G ') in the rubbery region and an asymmetric broadening of the loss modulus ( G ″) peak in the α -transition region. NS measurements show a suppressed hydrogen mean-square displacement (MSD) in the presence of glass fibers but a higher hydrogen MSD after grafting functionalized CNTs onto fiber surfaces. PALS measurements show greater free volume characteristics in the presence of the functionalized CNT modified composites, supporting the view that these interface layers increase polymer mobility. While NS and DMTA are sensitive to different modes of chain dynamics, the localization of functionalized nanotubes at the fiber interface is found to affect the distribution of polymer relaxation modes without significantly altering the thermally activated relaxation processes., Competing Interests: The authors declare no competing financial interest.

Quasielastic neutron scattering (QENS) measurements over a wide range of energy resolutions were used to probe the reorientational behavior of the pyramidal SiH 3 - anions in the monoalkali silanides (MSiH 3 , where M = K, Rb, and Cs) within the low-temperature ordered β -phases, and for CsSiH 3 , the high-temperature disordered α -phase and intervening hysteretic transition region. Maximum jump frequencies of the β -phase anions near the β - α transitions range from around 10 9 s -1 for β -KSiH 3 to 10 10 s -1 and higher for β -RbSiH 3 and β -CsSiH 3 . The β -phase anions undergo uniaxial 3-fold rotational jumps around the anion quasi- C 3 symmetry axis. CsSiH 3 was the focus of further studies to map out the evolving anion dynamical behavior at temperatures above the β -phase region. As in α -KSiH 3 and α -RbSiH 3 , the highly mobile anions (with reorientational jump frequencies approaching and exceeding 10 12 s -1 ) in the disordered α -CsSiH 3 are all adequately modeled by H jumps between 24 different locations distributed radially around the anion center of gravity, although even higher anion reorientational disorder cannot be ruled out. QENS data for CsSiH 3 in the transition region between the α - and β -phases corroborated the presence of dynamically distinct intermediate ( i -) phase. The SiH 3 - anions within i -phase appear to undergo uniaxial small-angular-jump reorientations that are more akin to the lower-dimensional β -phase anion motions rather than to the multidimensional α -phase anion motions. Moreover, they possess orientational mobilities that are an order-of-magnitude lower than those for α -phase anions but also an order-of-magnitude higher than those for β -phase anions. Combined QENS and neutron powder diffraction results strongly suggest that this i -phase is associated chiefly with the more short-range-ordered, nanocrystalline portions (invisible to diffraction) that appear to dominate the CsSiH 3 ., Competing Interests: The authors declare no competing financial interest.

Assessing the effects of an antimicrobial stewardship program (ASP) implemented in a 78-bed Internal Medicine ward of an Italian mid-sized acute care hospital of 296 beds (26,820 bed days/year in 2015 and 26,653 in 2016). The ASP, implemented in May 2016, included: (a) formulation and dissemination of local guidelines on empiric antibiotic therapy; (b) educational training; and (c) restrictive control on the use of carbapenems. We included in the study all the patients who had received at least one systemic antibiotic as empiric therapy and who were discharged in two comparable time periods (Oct-Nov 2015: period 1 and Oct-Nov 2016: period 2), before and after the implementation of the ASP. Clinical data were collected to compare the two study periods. The percentage of patients treated with antibiotics was significantly lower in period 2 (272/635 = 42.8% vs 238/648 = 36.7%, - 6.1%, p < 0.01). A similar reduction was observed in terms of defined daily doses per 100 bed days (from 49.5 to 46.9; - 5.3%). In period 2, we observed a significant reduction of patients treated with carbapenems (5.7 vs 2.1%, p < 0.05). The length of hospital stay and in-hospital mortality was similar in the two study periods. The implementation of an ASP in our Internal Medicine ward has been associated with a significant reduction of patients treated with antibiotics. The reduction was particularly relevant for carbapenems, antibiotics which should be used only in selected cases. These results have been obtained without increasing length of hospital stay and in-hospital mortality.

Metallic zinc (Zn) has been regarded as an ideal anode material for aqueous batteries because of its high theoretical capacity (820 mA h g -1 ), low potential (-0.762 V versus the standard hydrogen electrode), high abundance, low toxicity and intrinsic safety. However, aqueous Zn chemistry persistently suffers from irreversibility issues, as exemplified by its low coulombic efficiency (CE) and dendrite growth during plating/ stripping, and sustained water consumption. In this work, we demonstrate that an aqueous electrolyte based on Zn and lithium salts at high concentrations is a very effective way to address these issues. This unique electrolyte not only enables dendrite-free Zn plating/stripping at nearly 100% CE, but also retains water in the open atmosphere, which makes hermetic cell configurations optional. These merits bring unprecedented flexibility and reversibility to Zn batteries using either LiMn 2 O 4 or O 2 cathodes-the former deliver 180 W h kg -1 while retaining 80% capacity for >4,000 cycles, and the latter deliver 300 W h kg -1 (1,000 W h kg -1 based on the cathode) for >200 cycles.

The intermediate scattering functions of concentrated solutions of LiPF 6 in propylene carbonate (PC) were measured at various temperatures, two different wavenumbers, and three different concentrations using neutron spin echo (NSE) spectroscopy. The temperature dependence of the relaxation time was larger than that of the steady-state shear viscosity in all cases. The shear relaxation spectra were also determined at different temperatures. The normalized spectra reduced to a master curve when the frequency was multiplied by the steady-state shear viscosity, indicating that the temperature dependence of the steady-state shear viscosity can be explained by that of the relaxation time of the shear stress. It is thus suggested that the dynamics of the shear stress is decoupled from the structural dynamics on the molecular scale.

A neutron scattering technique was developed to measure the density of heavy water confined in a nanoporous silica matrix in a temperature-pressure range, from 300 to 130 K and from 1 to 2,900 bars, where bulk water will crystalize. We observed a prominent hysteresis phenomenon in the measured density profiles between warming and cooling scans above 1,000 bars. We interpret this hysteresis phenomenon as support (although not a proof) of the hypothetical existence of a first-order liquid-liquid phase transition of water that would exist in the macroscopic system if crystallization could be avoided in the relevant phase region. Moreover, the density data we obtained for the confined heavy water under these conditions are valuable to large communities in biology and earth and planetary sciences interested in phenomena in which nanometer-sized water layers are involved.

Background: Capsule enteroscopy is considered the gold standard for evaluating patients with obscure gastrointestinal bleeding. The costs of capsule enteroscopy examination, however, make it uncertain whether the clinically relevant diagnostic gain is also associated with cost savings., Aim: To evaluate the incremental cost-effectiveness ratio of capsule enteroscopy in patients with obscure gastrointestinal bleeding., Methods: Retrospective study was carried out in nine Italian gastroenterology units from 2003 to 2005. Data on 369 consecutive patients with obscure gastrointestinal bleeding were collected. The diagnostic yield of capsule enteroscopy vs. other imaging procedures was evaluated as a measure of efficacy. The values of Diagnosis Related Group 175 (euro 1884.00 for obscure-occult bleeding and euro 2141.00 for obscure-overt bleeding) were calculated as measures of economic outcomes in the cost analysis., Results: Obscure and occult gastrointestinal bleeding was recorded in 177 patients (48%) with a mean duration of anemia history of 17.6+/-20.7 months. Among patients, 60.9% had had at least one hospital admission, 21.2% at least two, and 1.2% of obscure bleeders up to nine admissions. Overall, 58.4% of patients had positive findings with capsule enteroscopy compared with 28.0% with other imaging procedures (P<0.001). The mean cost of a positive diagnosis with capsule enteroscopy was euro 2090.76 and that of other procedures was euro 3828.83 with a mean cost saving of euro 1738.07 (P<0.001) for one positive diagnosis., Conclusions: Capsule enteroscopy is a cost-saving approach in the evaluation of patients with obscure gastrointestinal bleeding.

The diffusion of wireless technology has caused concerns about interference in the hospital environment. Most hospitals have banned the use of cell phones on their premises although wireless technology can help in delivering time critical help to patients. We discuss some factors of radio frequency (RF) near field interference. These phenomena do not lend themselves easily to theoretical evaluation. It is possible to avert medical equipment interference by performing ad hoc tests. The method requires measurements of electromagnetic fields and the observation of interference events with increasing distance between equipment and RF transmitters. The results are applicable only to the specific testing environment. The ad hoc proposed method can be found in the draft document C63.18 of the American National Standard Institute.

By confining water in nanopores, so narrow that the liquid cannot freeze, it is possible to explore its properties well below its homogeneous nucleation temperature T(H) approximately equals 235 K. In particular, the dynamical parameters of water can be measured down to 180 K, approaching the suggested glass transition temperature T(g) approximately equals 165 K. Here we present experimental evidence, obtained from Nuclear Magnetic Resonance and Quasi-Elastic Neutron Scattering spectroscopies, of a well defined decoupling of transport properties (the self-diffusion coefficient and the average translational relaxation time), which implies the breakdown of the Stokes-Einstein relation. We further show that such a non-monotonic decoupling reflects the characteristics of the recently observed dynamic crossover, at approximately 225 K, between the two dynamical behaviors known as fragile and strong, which is a consequence of a change in the hydrogen bond structure of liquid water.