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Chiral materials are attracting considerable interest in various fields in view of their unique properties and optical activity. Indeed, the peculiar features of chiral materials to absorb and emit circularly polarized light enable their use in an extensive range of applications. Motivated by the interest in boosting the development of chiral materials characterized by enhanced chiroptical properties such as circular dichroism (CD) and circular polarized luminescence (CPL), we herein illustrate in this tutorial how theoretical simulations can be used for the predictions and interpretations of chiroptical data and for the identification of chiral geometries. We are focusing on computational frameworks that can be used to investigate the theoretical aspects of chiral materials' photophysical and conformational characteristics. We will then illustrate ab initio methods based on density functional theory (DFT) and its time‐dependent extension (TD‐DFT) to simulate CD and CPL signals, and we will exemplify a variety of enhanced sampling techniques useful for an adequate sampling of the configurational space for chiral systems. [ABSTRACT FROM AUTHOR]

High-flow therapy (HFT) is the administration of gas flows above 15 L/min. It is a non-invasive respiratory support that delivers heated (up to 38 °C), humidified (100% Relative Humidity, RH; 44 mg H2O/L Absolute Humidity, AH), oxygen-enriched air when necessary, through a nasal cannula or a tracheostomy interface. Over the last few years, the use of HFT in critically ill hypoxemic adults has increased. Although the clinical benefit of home high-flow therapy (HHFT) remains unclear, some research findings would support the use of HHFT in chronic respiratory diseases. The aim of this review is to describe the HFT physiological principles and summarize the published clinical findings. Finally, we will discuss the differences between hospital and home implementation, as well as the various devices available for HHFT application. [ABSTRACT FROM AUTHOR]

• The recording of esophageal pressure, when starting Non invasive Respiratory Support (NRS), may explain the potential risk in terms of Patient Self Induced Lung Injury and ventilator induced lung injury. • Non-invasive ventilation improved the inspiratory effort versus all the other devices, keeping transpulmonary pressure constant in patients in the early phase of acute respiratory failure due to COVID-19 infection • This short-term physiological study is the first comparison of respiratory mechanics between all the 3 major forms of NRS applied in spontaneously breathing patients with COVID-19 developing Hypoxemic Acute Respiratory Failure, without chronic respiratory disease. Various forms of Non-invasive respiratory support (NRS) have been used during COVID-19, to treat Hypoxemic Acute Respiratory Failure (HARF), but it has been suggested that the occurrence of strenuous inspiratory efforts may cause Self Induced Lung Injury(P-SILI). The aim of this investigation was to record esophageal pressure, when starting NRS application, so as to better understand the potential risk of the patients in terms of P-SILI and ventilator induced lung injury (VILI). 21 patients with early de-novo respiratory failure due to COVID-19, underwent three 30 min trials applied in random order: high-flow nasal cannula (HFNC), continuous positive airway pressure (CPAP), and non-invasive ventilation (NIV). After each trial, standard oxygen therapy was reinstituted using a Venturi mask (VM). 15 patients accepted a nasogastric tube placement. Esophageal Pressure (ΔPes) and dynamic transpulmonary driving pressure (ΔPLDyn), together with the breathing pattern using a bioelectrical impedance monitor were recorded. Arterial blood gases were collected in all patients. No statistically significant differences in breathing pattern and PaCO 2 were found. PaO 2 /FiO 2 ratio improved significantly during NIV and CPAP vs VM. NIV was the only NRS to reduce significantly ΔPes vs. VM (-10,2 ±5 cmH20 vs -3,9 ±3,4). No differences were found in ΔPLDyn between NRS (10,2±5; 9,9±3,8; 7,6±4,3; 8,8±3,6 during VM, HFNC, CPAP and NIV respectively). Minute ventilation (Ve) was directly dependent on the patient's inspiratory effort, irrespective of the NRS applied. 14% of patients were intubated, none of them showing a reduction in ΔPes during NRS. In the early phase of HARF due to COVID-19, the inspiratory effort may not be markedly elevated and the application of NIV and CPAP ameliorates oxygenation vs VM. NIV was superior in reducing ΔPes, maintaining ΔPLDyn within a range of potential safety. [ABSTRACT FROM AUTHOR]

Respiratory involvement of nemaline myopathy is evident on the diaphragm and intercostal muscles function. The present case study aimed to describe the characteristics of the respiratory physiotherapeutic treatment in a patient with nemaline myopathy. Here, we describe a case of a 43-yearold woman with nemaline myopathy undergoing pulmonary rehabilitation during short hospital admission for an acute exacerbation. At the time of hospitalisation, the patient was already under oxygen therapy (1 L/min) and noninvasive home ventilation using bi-level positive airway pressure with a nasal interface. Supplementary therapeutic exercises were implemented in addition to daily nasal noninvasive ventilation. At discharge, ultrasound examination revealed increased diaphragm trophism if compared with data obtained at hospital admission. [ABSTRACT FROM AUTHOR]

[Display omitted] • The dissociation mechanism of the zinc ion from the Atox1 homodimer is herein shown. • A stepwise dissociation pathway of the zinc ion from Atox1 was predicted. • The two free-energy values was estimated as 6 kcal/mol and 11 kcal/mol. The copper chaperone Atox1, which is featured by a peculiar CxxC metal-binding motif, is a protein involved in copper trafficking to the Golgi organelle, allowing the delivery of copper ions to specific target proteins in the secretory pathway. Various experimental studies suggest that this cysteine-containing protein may also be implicated in Zn(II) ion binding, functioning as a regulatory factor. However, despite the relevance of this interaction, the mechanism of zinc ion dissociation from the Atox1 homodimer has not yet been elucidated. We herein devised a simulation workflow based on the combination of parallel bias metadynamics and free energy perturbation theory, to predict the dissociation of the zinc ion from the Atox1 homodimer. The freeenergy simulations successfully predicted the dissociation free energy differences of the process, disclosing a mechanism based on a stepwise dissociation pathway of the zinc ion from the Atox1 homodimer. [ABSTRACT FROM AUTHOR]

[Display omitted] • Drug delivery systems made of Keratin/PLA nanofibers loaded with GO were prepared. • The GO improves the rheological properties of the solutions for electrospinning. • Solutions at higher conductivity and shear thinning lead to thinner nanofibers. • GO contributes to slow down the Rhodamine release. • GO contributes to reduce the matrix swelling release mechanism. In this work keratin/poly(lactic acid) (PLA) 50/50 wt blend nanofibers with different loadings of graphene-oxide (GO) were prepared by electrospinning and tested as delivery systems of Rhodamine Blue (RhB), selected as a model of a drug. The effect of GO on the electrospinnability and drug release mechanism and kinetics was investigated. Rheological measurements carried out on the blend solutions revealed unsatisfactory compatibility between keratin and PLA under quiet condition. Accordingly, poor interfacial adhesion between the two phases was observed by SEM analysis of a film prepared by solution casting. On the contrary, keratin chains seem to rearrange under the flux conditions of the electrospinning process thus promoting better interfacial interactions between the two polymers, thereby enhancing their miscibility, which resulted in homogeneous and defect-free nanofibers. The loading of GO into the keratin/PLA solution contributes to increase its viscosity, its shear thinning behavior, and its conductivity. Accordingly, thinner and more homogeneous nanofibers resulted from solutions with a relatively high conductivity coupled with a pronounced shear thinning behavior. FTIR and DSC analyses have underlined, that while the PLA/GO interfacial interactions significantly compete with the PLA/keratin ones, there are no significant effects of GO on the structural organization of keratin in blend with the PLA. However, GO offers several advantages from the application point of view by slightly improving the mechanical properties of the electrospun mats and by slowing down the release of the model drug through the reduction of the matrix swelling. [ABSTRACT FROM AUTHOR]

Every biological and physicochemical process occurring in a fluid phase depends on the diffusion coefficient (D) of the species in solution. In the present work, a model to describe and fit the behaviour of D ${D}$ as a function of structure and extensive thermodynamics parameters in binary solutions of linear chain organic molecules is developed. Supporting experimental and computational evidences for this model are obtained by measuring D ${D}$ for a series of n ${n}$ ‐alcohols through a novel surface plasmon resonance method and molecular dynamics simulations. This allows to propose a kind of combined analysis to explain the dependence of D ${D}$ on various thermodynamic and structural parameters. The results suggest that for small linear systems in the range from 0 to 200 g mol−1 and under the assumption that the diffusive activation energy is a linear function of mass, D ${D}$ is strictly dependent on the molecular shape and on the relative strength of the solute‐solvent intermolecular forces represented by a parameter named R. The newly proposed approach can be utilized to characterize and monitor progressive changes in physicochemical properties for any investigated species upon increasing the dimension of the aggregate/molecule along a certain direction. [ABSTRACT FROM AUTHOR]

This article discusses a study conducted on the concentration profile inside a tubing system of a surface plasmon resonance (SPR) system. The researchers used newly designed experiments to detect the concentration profile and determine the diffusion coefficients of linear chain molecules in water. They also developed a model based on Eyring's theory of absolute rates, which introduced a fitting parameter to explore the interplay between intermolecular forces, rotational hindrance, and diffusion in aqueous solutions of linear chain organic molecules. The full research article provides more detailed information on the study. [Extracted from the article]

Objectives: Exposure to asbestos fibers can lead to different lung diseases, such as pleural thickening and effusion, asbestosis, mesothelioma, and lung cancer. These diseases are expected to peak in the next few years. The aim of the study was to validate ultrasonography (US) as a diagnostic tool in the management of lung diseases in subjects with a history of occupational exposure to asbestos. Methods: Fifty-nine retired male workers previously exposed to asbestos were enrolled in the study. Chest US was performed in all the subjects. The US operator was blinded to earlier performed computed tomography (CT) scan reports and images. The sonographic pathological findings were pleural thickening (with or without calcifications), peripheral lung consolidation, and focal sonographic interstitial syndrome and diffuse pneumogenic sonographic interstitial syndrome (pulmonary asbestosis). Significant US findings were recorded, stored, and subsequently compared with CT scans. Results: With some patients falling into more than one category, on CT scan, pleural thickening was reported in 33 cases (56%, 26 with calcifications), focal interstitial peripheral alterations in 23 (39%), asbestosis in 6 (10%), and peripheral lung consolidation in 13 cases (22%). Comparing each pathological condition to CT scan reports, US findings had high levels of sensitivity, specificity, positive, and negative predictive values. US did not prove effective for the detection of central lung nodules or diaphragmatic pleural thickenings. Chest US was considered to be the best technique to detect minimal pleural effusions (six subjects, 10%). Conclusions: Chest US might be considered an additional tool to follow up subjects occupationally exposed to asbestos who have already undergone CT scan examination and whose pathology is detectable by US as well. [ABSTRACT FROM AUTHOR]