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ABSTRACT In Gram-negative bacteria, the outer membrane (OM) is asymmetric, with lipopolysaccharides (LPS) in the outer leaflet and glycerophospholipids (GPLs) in the inner leaflet. The asymmetry is maintained by the Mla system (MlaA-MlaBCDEF), which contributes to lipid homeostasis by removing mislocalized GPLs from the outer leaflet of the OM. Here, we ascribed how Pseudomonas aeruginosa ATCC 27853 coordinately regulates pathways to provide defense against the threats posed by the deletion of mlaA. Especially, we explored (i) the effects on membrane lipid composition including LPS, GPLs, and lysophospholipids, (ii) the biophysical properties of the OM such as stiffness and fluidity, and (iii) the impact of these changes on permeability, antibiotic susceptibility, and membrane vesicles (MVs) generation. Deletion of mlaA induced an increase in total GPLs and a decrease in LPS level while also triggering alterations in lipid A structures (arabinosylation and palmitoylation), likely to be induced by a two-component system (PhoPQ-PmrAB). Altered lipid composition may serve a physiological purpose in regulating the mechanobiological and functional properties of P. aeruginosa. We demonstrated an increase in cell stiffness without alteration of turgor pressure and inner membrane (IM) fluidity in ∆mlaA. In addition, membrane vesiculation increased without any change in OM/IM permeability. An amphiphilic aminoglycoside derivative (3’,6-dinonyl neamine) that targets P. aeruginosa membranes induced an opposite effect on ∆mlaA strain with a trend toward a return to the situation observed for the WT strain. Efforts dedicated to understanding the crosstalk between the OM lipid composition, and the mechanical behavior of bacterial envelope, is one needed step for designing new targets or new drugs to fight P. aeruginosa infections.IMPORTANCEPseudomonas aeruginosa is a Gram-negative bacterium responsible for severe hospital-acquired infections. The outer membrane (OM) of Gram-negative bacteria acts as an effective barrier against toxic compounds, and therefore, compromising this structure could increase sensitivity to antibiotics. The OM is asymmetric with the highly packed lipopolysaccharide monolayer at the outer leaflet and glycerophospholipids at the inner leaflet. OM asymmetry is maintained by the Mla pathway resulting in the retrograde transport of glycerophospholipids from the OM to the inner membrane. In this study, we show that deleting mlaA, the membrane component of Mla system located at the OM, affects the mechanical and functional properties of P. aeruginosa cell envelope. Our results provide insights into the role of MlaA, involved in the Mla transport pathway in P. aeruginosa.

Unidirectional long fiber reinforced polymers generally exhibit unfavorable abrupt and brittle failure under mechanical stresses without pre-warning which currently limits their use in safety critical applications. The lack of ductility of such composites can be overcome by interlayer hybridization where Low Strain (LS) material is sandwiched between High Strain (HS) material. This results in complex failure mechanisms, including multiple interacting damage modes, such as ply fragmentation and delamination. All-carbon unidirectional hybrid laminates with different layup sequences were designed and manufactured to study the pseudo-ductile behavior. An available analytical model was exploited to predict the damage scenarios of the laminates, both with stress-strain diagrams and damage mode maps. Tensile tests were carried out using different measurement and observation techniques including digital image correlation (DIC), embedded distributed fiber optic sensors (dFOS) and helicoidal X-ray computed tomography (CT). A finite element model was also developed to predict the damage mechanisms. Validated by experimental results, the numerical model was found to accurately predict the tensile damage modes and their evolution in the considered unidirectional thick ply all-carbon hybrid laminates.

Abstract Background The aim of this manuscript is to illustrate a new method permitting safe cholecystectomy in terms of complications with respect to the common bile duct (CBD). Methods The core of this new technique is identification of the continuity of the cystic duct with the infundibulum. The cystic duct can be identified between the inner gallbladder wall and inflamed outer wall. Results In the last 2 years, from January 2019 until December 2021, 3 patients have been treated with the reported technique without complications. Conclusions Among the various cholecystectomy procedures, this is a new approach that ensures the safety of the structures of Calot’s triangle while providing the advantages gained from total removal of the gallbladder.

This study presents a comprehensive analysis and radiocarbon dating of historical mortar and plaster samples from the San Salvatore—Massino Visconti complex in Piedmont, Northern Italy. Mortar samples and one charcoal sample were collected from various areas within the complex’s lower chapels. Samples were selected and characterized by means of a multi-analytical approach in order to draw inferences about their compositional, mineralogical, and microstructural features. The identification of hydromagnesite and magnesite in the mortar samples suggests the usage of magnesian binder mortar, potentially affecting radiocarbon dating due to its slower carbonation kinetics when compared to calcitic mortars. To mitigate this effect, a purification method was developed involving thermal treatment at 550 °C to isolate datable binding fractions. The results yielded reliable radiocarbon ages consistent with historical context, shedding light on construction materials dating from the 12th to 16th centuries. The study also challenges previous notions by demonstrating the feasibility of radiocarbon dating for magnesian mortars, opening new perspectives for dating such materials. These findings offer valuable insights into the construction history and material composition of the complex, corroborating historical information.

Neuro-inflammation occurs in numerous disorders such as multiple sclerosis, Alzheimer's disease and Parkinson's disease. However, anti-inflammatory drugs for the central nervous system have failed to show significant improvement when compared to a placebo in clinical trials. Our previous work demonstrated that stem cells from the apical papilla (SCAP) can decrease neuro-inflammation and stimulate oligodendrocyte progenitor cell differentiation. One hypothesis is that the therapeutic effect of SCAP could be mediated by their secretome, including extracellular vesicles (EV). Here, our objectives were to characterize SCAP-EV and to study their effect on microglial cells. We isolated EV from non-activated SCAP and from SCAP activated with TNFα and IFN-γ and characterized them according to their size, EV markers, miRNA and lipid content. Their ability to decrease pro-inflammatory cytokine expression in vitro and ex vivo was also assessed. We showed that the miRNA content was impacted by a pro-inflammatory environment but not their lipid composition. SCAP-EV reduced the expression of pro-inflammatory markers in LPS-activated microglial cells while their effect was limited on mouse spinal cord sections. In conclusion, we were able to isolate EV from SCAP, to show that their miRNA content was impacted by a pro-inflammatory stimulus, and to describe that SCAP-EV and not the protein fraction of conditioned medium could reduce pro-inflammatory marker expression in LPS-activated BV2 cells.

Posterior cruciate ligament (PCL) injury is a rare ligamentous knee injury which most commonly occurs due to direct trauma; it represents only 0.65% of knee injuries. On the basis of magnetic resonance imaging (MRI), PCL injury is divided into surgical and non-surgical. In the last few years we have witnessed an increasing interest in regenerative medicine. The use of innovative techniques allow the reduction of rehabilitation times in sports injuries. Platelet-Rich-Plasma (PRP) is a plasma-derived which stimulate the tissue repair. The objective of our work is to compare the rehabilitation times in PCL non-operative injuries treated with standard conservative treatment and PCL injuries treated with autologous PRP followed by rehabilitation program. We divided patients into two different groups: Group A formed by patients who underwent a standard conservative rehabilitation program and Group B which included patients treated by ultrasound guided PRP injection and following physiotherapy program. Both groups of patients resumed sports activities; however the rehabilitation times for patients which had undergone treatment with autologous PRP injection were reduced compared to patients who underwent a standard conservative treatment.

Abstract The usage of semiconductor nanostructures is highly promising for boosting the energy conversion efficiency in photovoltaics technology, but still some of the underlying mechanisms are not well understood at the nanoscale length. Ge quantum dots (QDs) should have a larger absorption and a more efficient quantum confinement effect than Si ones, thus they are good candidate for third-generation solar cells. In this work, Ge QDs embedded in silica matrix have been synthesized through magnetron sputtering deposition and annealing up to 800°C. The thermal evolution of the QD size (2 to 10 nm) has been followed by transmission electron microscopy and X-ray diffraction techniques, evidencing an Ostwald ripening mechanism with a concomitant amorphous-crystalline transition. The optical absorption of Ge nanoclusters has been measured by spectrophotometry analyses, evidencing an optical bandgap of 1.6 eV, unexpectedly independent of the QDs size or of the solid phase (amorphous or crystalline). A simple modeling, based on the Tauc law, shows that the photon absorption has a much larger extent in smaller Ge QDs, being related to the surface extent rather than to the volume. These data are presented and discussed also considering the outcomes for application of Ge nanostructures in photovoltaics. PACS: 81.07.Ta; 78.67.Hc; 68.65.-k

The creation and maintenance of a stable and long-lasting relationship are crucial for adult individual well-being, with single people reporting poorer mental health when compared to those engaged in romantic relationships. Among the factors that may predict the quality of romantic dyads, scholars have addressed dyadic perfectionism. However, few is known about which of the perfectionism dimensions better predicts the status of being single or engaged in a romantic relationship. The present study aims to verify whether perfectionism is associated with the relationship status, and which perfectionism dimension is involved. More specifically, the interpersonal aspects of dyadic perfectionism were expected to be positively associated with the probability of belonging to the 'single status'. Contributions of demographic variables as well as effects of mental health symptoms were controlled as they are relevant factors influencing romantic relationships. A hierarchical logistic regression analysis was conducted to evaluate the predictive utility of age and gender (controlled for at Step 1), depression and anxiety (entered at Step 2) and intra-and interpersonal perfectionism dimensions (controlled at Step 3) to predict the participants' relationship status (0 = single, 1 = romantic partner). Results suggested that perfectionism focused on the perceived perfectionistic expectations from the partner is associated with the increased likelihood to be single, a result that confirmed the close association between maladaptive perfectionism and relevant aspects of romantic relationships., Author(s): Mariacarolina Vacca [sup.1] , Michela Terrasi [sup.1] , Rita Maria Esposito [sup.1] [sup.2] , Caterina Lombardo [sup.1] Author Affiliations: (1) grid.7841.a, Department of Psychology, Sapienza University of Rome, , [...]

This study presents a comprehensive analysis and radiocarbon dating of historical mortar and plaster samples from the San Salvatore—Massino Visconti complex in Piedmont, Northern Italy. Mortar samples and one charcoal sample were collected from various areas within the complex's lower chapels. Samples were selected and characterized by means of a multi-analytical approach in order to draw inferences about their compositional, mineralogical, and microstructural features. The identification of hydromagnesite and magnesite in the mortar samples suggests the usage of magnesian binder mortar, potentially affecting radiocarbon dating due to its slower carbonation kinetics when compared to calcitic mortars. To mitigate this effect, a purification method was developed involving thermal treatment at 550 °C to isolate datable binding fractions. The results yielded reliable radiocarbon ages consistent with historical context, shedding light on construction materials dating from the 12th to 16th centuries. The study also challenges previous notions by demonstrating the feasibility of radiocarbon dating for magnesian mortars, opening new perspectives for dating such materials. These findings offer valuable insights into the construction history and material composition of the complex, corroborating historical information. [ABSTRACT FROM AUTHOR]

Green hydrogen production by water splitting holds great potential as a clean and renewable source of energy for sustainable energy solutions. However, the efficiency of this process is hampered by the sluggish oxygen evolution reaction (OER). Overcoming these kinetic hurdles requires the development of highly efficient electrocatalysts. This study explores the effect of transition metal doping on the electrocatalytic properties of Ni(OH)2 microflowers towards alkaline OER. Transition metal‐doped Ni(OH)2 microflowers, with highly porous structures due to interconnected nanosheets, are synthesized by a facile, cheap, and scalable chemical bath deposition (CBD), and combined with graphene paper (GP) substrates to fabricate electrodes. Through a systematic exploration of the relationship between the transition metal dopant element type (Mn, Fe, Co, Zn) or concentration and the consequent electrochemical properties, Co‐doping demonstrates improvement in the overpotential at a current density of 10 mA cm−2 (329 mV), Tafel slope (45 mV dec−1), and other key performance indicators of Ni(OH)2 microflowers for OER. These results are attributed to the high number of active sites and their enhanced electrocatalytic activity benefiting from the presence of the transition metal dopant. The proposed strategy paves the way for the development of cost‐effective and highly efficient electrocatalysts for water splitting technologies. [ABSTRACT FROM AUTHOR]

This study analyzed the long-term effects of carrier-bound fibrin sealant (CBFS) following abdominal surgery by tracking patients for years post-application. From 2006 to 2022, patients who underwent this procedure were contacted via telephone. Those who died due to underlying diseases, natural causes, or refused the check-up were excluded from the study. After 11 years of follow-up, CBFS was observed in different forms on computed tomography scans in four patients. Our findings indicate that CBFS can persist for years after the procedure. While we cannot confirm any secondary effects, it appears that CBFS sponges are not resorbed within 12 weeks and can remain for many years post-implantation. [ABSTRACT FROM AUTHOR]