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Symmetry-breaking is pivotal for controlling ferroelectric, ferroelastic and/or ferromagnetic functions of materials, which enables applications in sensors, memory devices, transducers or actuators. Commonly, ferroic phases emerge from descending symmetry-breaking, as the laws of thermodynamics dictate that the ordered low entropy phases form at low temperature, which limits practical applications of many materials at room temperature. Rare examples of ascending symmetry-breakings have been observed, but the driving force remains often unclear. Here, we report on a ferroelastic symmetry-breaking occurring at high temperature in a spin-crossover material, studied by magnetic, DSC and X-ray diffraction measurements. Our DFT calculations and our model, based on the Landau theory of phase transitions, explain how the cooperative thermal switching of the molecular spin state drives a ferroelastic symmetry breaking at high temperature, through a coupled Jahn-Teller distortion. Ferroelastic materials have rich properties, with important applications in memory, multifunctional and novel controllable devices. The electronic bistability in soft functional materials represents an important source of entropy gain, capable of overcoming the cost of symmetry-breaking entropy, which opens up new perspectives for stabilizing high-temperature and low-symmetry ferroic functions of advanced materials.

Nanoporous solids offer a wide range of functionalities for industrial, environmental, and energy applications. However, only a limited number of porous materials are responsive, i.e. the nanopore dynamically alters its size and shape in response to external stimuli such as temperature, pressure, light or the presence of specific molecular stimuli adsorbed inside the voids deforming the framework. Adsorption-induced structural deformation of porous solids can result in unique counterintuitive phenomena. Negative gas adsorption (NGA) is such a phenomenon which describes the spontaneous release of gas from an "overloaded" nanoporous solid via adsorption-induced structural contraction leading to total pressure amplification (PA) in a closed system. Such pressure amplifying materials may open new avenues for pneumatic system engineering, robotics, damping, or micromechanical actuators. In this review we illustrate the discovery of NGA in DUT-49, a mesoporous metal-organic framework (MOF), and the subsequent examination of conditions for its observation leading to a rationalization of the phenomenon. We outline the development of decisive experimental and theoretical methods required to establish the mechanism of NGA and derive key criteria for observing NGA in other porous solids. We demonstrate the application of these design principles in a series of DUT-49-related model compounds of which several also exhibit NGA. Furthermore, we provide an outlook towards applying NGA as a pressure amplification material and discuss possibilities to discover novel NGA materials and other counterintuitive adsorption phenomena in porous solids in the future.

Research has shown that heightened emotionality often precedes psychotic experiences. Understanding how individuals cope with these emotions is crucial for psychosis. While prior studies on emotion regulation (ER) and psychosis have mainly relied on self-report questionnaires, recent research has increasingly utilised daily life methods. This systematic review and meta-analysis seek to examine the relationship between daily ER and psychotic experiences. In total, 15 studies were included in the meta-analysis (21 in the systematic review). The results of Experience Sampling Methods (ESM) studies indicated that ER strategies of avoidance, reappraisal, repetitive thinking, and emotional suppression are not associated with psychotic experiences in daily life. The effect was not moderated by type of sample (clinical vs non-clinical), symptom (hallucination vs delusions), relation (contemporaneous vs perspective), or other methodological variables. Acceptance was found to be negatively associated with psychotic experiences, but the effect was small. These results indicate that ER in daily life might not impact directly on psychotic experiences. The results are discussed in light of conceptual and methodological limitations in the field., Competing Interests: Declaration of Competing Interest None., (Copyright © 2025 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Here we present studies of the structure and membrane interactions of ecPis-4 s, a new antimicrobial peptide from the piscidin family, which shows a wide-range of potential biotechnological applications. In order to understand the mode of action ecPis-4 s, the peptide was chemically synthesized and structural investigations in the presence of anionic POPC:POPG (3:1, mol:mol) membrane and SDS micelles were performed. CD spectroscopy demonstrated that ecPis-4 s has a high content of helical structure in both membrane mimetic media, which is in line with solution NMR spectroscopy that revealed an amphipathic helical conformation throughout the entire peptide chain. Solid-state NMR experiments of ecPis-4 s selectively labeled with 15 N/ 2 H and reconstituted into uniaxially oriented POPC:POPG membranes revealed an ideal partition of hydrophilic and hydrophobic residues within the bilayer interface. The peptide aligns in parallel to the membrane surface, a topology stabilized by aromatic side-chain interactions of the Phe-1, Phe-2 and Trp-9 with the phospholipids. 2 H NMR experiments using deuterated lipids revealed that anionic lipid accumulates in the vicinity of the cationic peptide upon peptide-membrane binding., Competing Interests: Declaration of competing interest The authors have no conflicts of interest to declare relevant to this article's content., (Copyright © 2024. Published by Elsevier B.V.)

The mRNA splicing machinery has been estimated to generate 100,000 known protein-coding transcripts for 20,000 human genes (Ensembl, Sept. 2024). However, this set is expanding with the massive and rapidly growing data coming from high-throughput technologies, particularly single-cell and long-read sequencing. Yet, the implications of splicing complexity at the protein level remain largely uncharted. In this review, we describe the current advances toward systematically assessing the contribution of alternative splicing to proteome function diversification. We discuss the potential and challenges of using artificial intelligence-based techniques in identifying alternative splicing proteoforms and characterising their structures, interactions, and functions., Competing Interests: Declaration of competing interest None., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Background: While Alcohol Use Disorder (AUD) is frequently associated with impulsivity, its structural brain substrates are still poorly defined. The triadic model of addiction postulates that impulsive behavior is regulated by an amygdalo-striatal impulsive subcomponent, a prefrontal and cerebellar reflective subcomponent, and an insular regulatory subcomponent. The objective of this study was thus to examine the relationships between self-evaluated impulsivity and structural brain abnormalities in patients with severe AUD (sAUD) using the triadic model as a theoretical framework., Methods: Twenty-two inpatients with sAUD and 17 Healthy Controls (HC) completed two impulsivity scales: the Barratt Impulsiveness Scale-11 (BIS-11), and the Urgency, Premeditation, Perseverance, Sensation Seeking, Positive Urgency Impulsive Behavior Scale (UPPS). They also underwent an anatomical MRI. The brain volumes of the regions described as involved in the three subcomponents of the triadic model were extracted., Results: The two groups did not significantly differ on self-reported impulsivity measures. However, the volumes of the caudate nuclei, executive cerebellum and insula were smaller in sAUD than in HC. In the sAUD group there were significant positive correlations between certain impulsivity measures and gray matter volume of the nucleus accumbens., Conclusions: In sAUD, self-evaluated impulsivity specifically relates to the integrity of the ventral striatum that belongs to the impulsive subcomponent of the triadic neurocognitive model of addiction. It is not related to the integrity or deterioration of the brain regions that underlie the reflexive or regulatory sub-component. Although these results have methodological limitations, they are consistent with the impulsive/compulsive model of addiction and confirms the persistence of the relationship between impulsivity and ventral striatum in sAUD., Competing Interests: Declaration of Competing Interest none, (Copyright © 2025 The Authors. Published by Elsevier B.V. All rights reserved.)

Allosteric regulation is a powerful mechanism for controlling the efficiency of enzymes. Deciphering the evolutionary mechanisms by which allosteric properties have been acquired in enzymes is of fundamental importance. We used the malate (MalDH) and lactate deydrogenases (LDHs) superfamily as model to elucidate this phenomenon. By introducing a few of mutations associated to the emergence of allosteric LDHs into the non-allosteric MalDH from Methanopyrus kandleri, we have gradually shifted its enzymatic profile toward that typical of allosteric LDHs. We first investigated the process triggering homotropic activation. The structures of the resulting mutants show the typical compact organization of the R-active state of LDHs, but a distorted (T-like) catalytic site demonstrating that they corresponds to hybrid states. Molecular dynamics simulations and free energy calculations confirmed the capability of these mutants to sample the T-inactive state. By adding a final single mutation to fine-tune the flexibility of the catalytic site, we obtained an enzyme with both sigmoid (homotropic) and hyperbolic (heterotropic) substrate activation profiles. Its structure shows a typical extended T-state as in LDHs, whereas its catalytic state has as a restored configuration favorable for catalysis. Free energy calculations indicate that the T and R catalytic site configurations are in an equilibrium that depends on solvent conditions. We observed long-range communication between monomers as required for allosteric activation. Our work links the evolution of allosteric regulation in the LDH/MDH superfamily to the ensemble model of allostery at molecular level, and highlights the important role of the underlying protein dynamics., Competing Interests: Conflict of Interest: The authors declare that they have no conflicts of interest with the contents of this article., (© The Author(s) 2025. Published by Oxford University Press on behalf of Society for Molecular Biology and Evolution.)

The lipid cis-trans isomerase (Cti) is a periplasmic heme-c enzyme found in several bacteria including Pseudomonas aeruginosa, a pathogen known for causing nosocomial infections. This metalloenzyme catalyzes the cis-trans isomerization of unsaturated fatty acids in order to rapidly modulate membrane fluidity in response to stresses that impede bacterial growth. As a consequence, breakthrough in the elucidation of the mechanism of this metalloenzyme might lead to new strategies to combat bacterial antibiotic resistance. We report the first comprehensive biochemical, electrochemical and spectroscopic characterization of a Cti enzyme. This has been possible by the successful purification of Cti from P. aeruginosa (Pa-Cti) in favorable yields with enzyme activity of 0.41 μmol/min/mg when tested with palmitoleic acid. Through a synergistic approach involving enzymology, site-directed mutagenesis, Raman spectroscopy, Mössbauer spectroscopy and electrochemistry, we identified the heme coordination and redox state, pinpointing Met163 as the sixth ligand of the Fe II of heme-c in Pa-Cti. Significantly, the development of an innovative assay based on liposomes demonstrated for the first time that Cti catalyzes cis-trans isomerization directly using phospholipids as substrates without the need of protein partners, answering the important question about the substrate of Cti within the bacterial membrane., (© 2024 The Author(s). ChemBioChem published by Wiley-VCH GmbH.)

In medical emergencies, phoning the ambulance service constitutes a high-stakes interaction. Call-takers rely on callers to provide information about the patient so they can promptly recognise the medical problem and take swift action to remedy it. When a language barrier exists between the call-taker and caller, this can add a further challenge, given that third-party interpreters are rarely engaged, especially for time-critical conditions such as cardiac arrest. Research in cardiac arrest calls has found that language barrier calls experience longer delays to critical points such as recognition of cardiac arrest and commencement of resuscitation. This study aimed to understand, in the absence of interpreters, the interactional challenges that emerged in language barrier emergency calls, as parties worked to communicate the nature of the medical problem. Based on a critical conversation analysis approach, we conducted fine-grained analysis of interactions in audio recordings and transcripts of 33 language barrier calls from an Australian ambulance service in 2019. We found that call takers regularly failed to recognise that the patient had a cardiac arrest. Non-fluent-English callers often provided vital information about the patient, which could have led to cardiac arrest recognition by the call-taker, however such information was missed if it was delivered in an unsolicited or atypical way. Opportunities to recognise cardiac arrest were also missed when call-takers did not probe further after such information was provided or did not provide enough interactional space for callers to complete their turns. We found that the main reason for delays in recognising cardiac arrest was a lack of mutual understanding, which most of the time seemed to remain unbeknownst to participants. The study makes recommendations for emergency medical dispatch centres to cater for language barrier calls, with the goal of fostering a more inclusive prehospital care system and addressing health disparities for non-fluent-English speakers., Competing Interests: Conflicts of interest AW is employed by St John Western Australia (SJ-WA); JF and SB hold adjunct appointments with SJ-WA and JF receives research project funding from SJ-WA., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

This work explores two methods to encapsulate Thymoquinone (TQ) into lipid nanocapsules (LNCs) for oral administration. TQ was added during the phase inversion temperature method (TQ-LNCs-1) or to unload LNCs dispersion (TQ-LNCs-2). LNCs were evaluated for mean diameter, polydispersity index (PDI), ζ-potential, drug loading (DL), drop tensiometer, storage stability, in vitro stability in simulated gastrointestinal fluids (SGIF), and intestinal permeability across Caco-2 cells. TQ-LNCs-1 and TQ-LNCs-2 produced NPs (58.3 ± 3.7 nm and 61.5 ± 3.5 nm, respectively), with a DL of 8.7 ± 0.2 and 7.7 ± 0.6 mg/mL of suspension, respectively. For both, less than 14% of TQ was released in SGIF, and a minor increase in TQ intestinal permeability with LNCs compared to free TQ was observed. TQ-LNCs represented a promising formulation for oral delivery of TQ. Encapsulation of TQ by adding it at LNCs dispersion can be extended for further drugs.