Browse Articles

Comment on “A random batch Ewald method for charged particles in the isothermal–isobaric ensemble” [J. Chem. Phys. 157, 144102 (2022)]

Phase Engineering of Atomically Dispersed Fe-Doped Amorphous RuO_<i>x</i> Nanosheets via Amorphous–Amorphous Transition for Oxygen Activation

The plant matrix of Artemisia annua L. for the treatment of malaria: Pharmacodynamic and pharmacokinetic studies

Artemisinin-based combination therapies (ACTs) constitute the principal strategy for combating malaria in contemporary times, and research into the multifaceted components of Artemisia annua L. (A. annua) has garnered widespread interest among scientists. The aim of this study was to prepare A. annua extracts (nACTs) and to explore whether nACTs have higher bioavailability and efficacy than artemisinin (ART) alone due to its multiple bioactive components. Initially, the in vivo antimalarial activity of nACTs was evaluated by two murine malaria models. The results revealed that the antimalarial effect of nACTs was about 10-fold higher than that of ART alone when administered at the same dosage of ART. Then, we analyzed the pharmacokinetic characteristics of nACTs in rat plasma. Remarkably, nACTs exhibited significantly enhanced oral bioavailability, longer half-life as well as extended mean retention time in rats. In addition, the impact of nACTs on P-glycoprotein (P-gp) was evaluated using the Caco-2 cell line. The results showed that both ART and nACTs reduced the efflux rate of the P-gp substrate rhodamine 123 (R123) and induced the expression of P-gp in Caco-2 cells over a range of concentrations. nACTs had certain components-deoxyartemisinin (DEART), artemisinic acid (AA), and dihydroartemisinic acid (DHAA)-that inhibited the efflux and translocation of P-gp and facilitated the reduction of ART efflux. In conclusion, A. annua extracts significantly improved the antimalarial efficacy and bioavailability compared with ART.

Qualitative approach to compare hysteretic models via restoring force surfaces

On the modeling of hydrocarbon combustion in external electric fields with reactive molecular dynamics

The use of electric fields may provide a mechanism to enable fuel-flexible technologies in aviation. The development of such technologies requires methodologies able to accurately quantify electric field effects on chemical reactions at the molecular level. This work provides a comprehensive assessment of methodologies used in the framework of reactive molecular dynamics (MD) with the reactive force field ReaxFF. The focus is on the computation of atomic charges, the method used for equilibration, and the use of global thermostats for hydrocarbon combustion in an external electric field. The charge equilibration method (QEq) and the charge transfer with polarization current equilibration method (QTPIE) were analyzed for the computation of atomic charges. For the fuel–oxygen system investigated, QEq leads to molecules with a sizable spurious net charge. QTPIE leads to more accurate molecular charges but at the cost of underestimating some atomic charges. This leads to faster combustion kinetics with QEq compared with QTPIE. A two-step equilibration procedure provides a more equilibrated system compared to widely used equilibration procedures. Furthermore, using a global thermostat with an external electric field results in an artificial reduction in fuel and oxygen first-order reaction rates. These artificial effects can be avoided by not using a thermostat, but at the expense of electric-field-induced heating. Applying an external electric field without a global thermostat accelerates combustion much more with QEq compared with QTPIE, due to the larger charges predicted by QEq. This study reveals several simulation artifacts that affect reactive MD of fuel combustion and contributes toward the more accurate modeling of fuel combustion in external electric fields.

Photocatalyst-Dependent Enantioselectivity in the Light-Driven Deracemization of Cyclic α-Aryl Ketones

In-depth investigation of genome to refine QTL positions for spontaneous sex-reversal in XX rainbow trout

Sex determination is a flexible process in fish, controlled by genetics or environmental factors or a combination of both depending on the species. Revealing the underlying molecular mechanisms may have important implications for research on reproductive development in vertebrates, as well as sex-ratio control and selective breeding in fish. Phenotypic sex in rainbow trout ( Oncorhynchus mykiss ) is primarily controlled by a XX/XY male heterogametic sex determination system. Unexpectedly in genetically XX all-female farmed populations, a small proportion of males or intersex individuals are regularly observed. Spontaneous masculinisation is a highly heritable trait, controlled by minor sex-modifier genes that remain unknown, although several Quantitative Trait Loci (QTL) were detected in previous studies. In the current work we used genome-based approaches and various statistical methods to further investigate these QTL. DNA markers that were previously identified in a French commercial population on chromosomes Omy1, Omy12 and Omy20 were validated in six different farmed trout populations. Functional candidate genes that may be involved in spontaneous masculinisation by reducing germ cell proliferation and repressing oogenesis of XX-rainbow trout in the absence of the master sex determining gene were identified. In particular, syndig1 , tlx1 and hells on Omy1, as well as khdrbs2 and csmd1 on Omy20 deserve further investigation to validate their potential sex-modifier roles as well as their interaction with rearing temperature. Those findings could be used to produce all-female populations that are preferred by farmers due to a delayed maturation of females and higher susceptibility of male trout to diseases.

Exploring past and future fluency of temporal landmarks under reduced agency

Abstract Significant temporal landmarks often involve high emotionality, thereby deeply imprinting within one’s autobiographical memory. In this study we explore the connection between anticipation, temporal landmarks, subjective passage of time and perceived wellbeing. We do this by conducting a three-stage mixed method study including qualitative thematic analysis, AI-assisted coding and analysis, and quantitative negative binomial multivariate analysis of the Past Fluency and Future Fluency reported events (n = 73,244) provided by n = 1,113 participants across the six reported (future and past) temporal horizons (One Week, One Month, One Year) in the Blursday Database during the COVID-19 pandemic. Our findings show that participants state more past Temporal Landmarks compared with future, while the opposite is true for Utilitarian Activities. Key sex differences exist in men’s vs. women’s identification of Utilitarian Activities (greater future fluency), Temporal Landmarks (greater past fluency) and fewer Discretionary Activities listed for both past and future fluency. Statistically significant relationships are found with responses about stringency of lockdown restrictions and subjective assessments of confinement. Our study provides novel methodology and findings that demonstrate how engagement in anticipatory behaviour can be considered a type of time work, where an individual intentionally alters or customizes temporal experiences during times of reduced agency.

Data-driven discovery of single-atom catalysts for CO2 reduction considering the pH-dependency at the reversible hydrogen electrode scale

The electrochemical carbon dioxide reduction reaction (CO2RR) represents a promising approach to mitigating climate change and addressing energy challenges by converting CO2 into value-added chemicals. Among various CO2RR products, CO is attractive due to its economic viability and industrial relevance. By integrating large-scale data mining (with 939 experimental performance data), we reveal that the catalytic performance of d-block transition metal-based single-atom catalysts (SACs) for CO2RR is influenced not only by the coordination environment but also significantly by pH. However, the unified model that could accurately depict the pH-dependent CO2RR to CO activity of d-block SACs is urgently needed. Herein, we conducted pH-dependent microkinetic modeling based upon density functional theory calculations and pH-electric field coupled microkinetic modeling to analyze CO2RR performance of 101 SACs. Our data-driven screening identifies 12 high-performance SACs with promising CO selectivity across different pH conditions, primarily based on Fe, Cu, and Ni centers. We establish a scaling relation between key intermediates (*COOH and *CO) and analyze their adsorption behaviors under varying electrochemical conditions. Furthermore, our pH-dependent microkinetic modeling reveals the critical role of electric field effects in determining catalytic performance, aligning well with experimental turnover frequency values. Most importantly, our theoretical model accurately captures the pH-dependent performance of CO2RR-to-CO on d-block SACs, which is experimentally validated and serves as a general theoretical framework for the rational design of high-performance CO2RR catalysts. Based on this model, we identify a series of promising M–N–C catalysts, providing a universal design principle for optimizing CO2-to-CO conversion.

Particle Hopping and Coalescence of Supported Au Nanoparticles in Harsh Reactive Environments

‘It’s not just immoral!’: The role of moral disengagement and incivility in dehumanising the transgressor of immoral behaviour

People who engage in immoral behaviour are often dehumanised. However, they also tend to justify their actions to convince themselves or others that their misconduct is morally acceptable. In this paper, we examine whether moral disengagement mechanisms influence the extent to which a transgressor is perceived as fully human. Further, we assess whether this perception varies based on specific characteristics of the immoral behaviour, such as incivility. To answer these research questions, we conducted two studies with online participants from Spain. In Study 1, participants (N = 302) evaluated a set of 63 behaviours. For every behaviour, they assessed the extent to which it violated each moral foundation from moral foundations theory, its level of incivility, and its potential to elicit dehumanisation. A correlation analysis showed that only the care and purity foundations, along with incivility, were associated with dehumanisation. These results allowed us to select behaviours that varied in incivility for Study 2. In Study 2 (N = 402), we tested the effectiveness of moral disengagement mechanisms employed by the transgressor depending on the level of incivility of the immoral behaviour. To this end, we employed a 3 (moral disengagement mechanisms: moral justification vs. displacement of responsibility vs. distortion of consequences) x 2 (incivility: high vs. low) between-subjects experimental design. The variance analyses showed that using moral justification or displacement of responsibility led to the least amount of dehumanisation, while distortion of consequences resulted in the highest level of dehumanisation. Additionally, immoral behaviours that were high in incivility led to greater dehumanisation than those that were low in incivility, regardless of the moral disengagement mechanism. Overall, our research highlights the significance of different moral disengagement mechanisms and civility as key factors that affect how bystanders perceive the humanness of moral transgressors.

Serum β2-microglobulin level is associated with the survival of HIV-associated diffuse large B-cell lymphoma: a retrospective study from China

Dynamics of an active chiral polymer in shear flow

We explore the complex formation of an active flexible polymer chain in linear shear flow by using monomer-resolved Brownian dynamics simulations in two spatial dimensions. The chiral head monomer is active and circling, while all other monomers are passive, following both the motion of the head polymer and the shear flow. By the combination of activity, chirality, and shear rate, a wealth of different states are found, including the formation of a linear/complex folding and a spiraling state with both head-in and head-out morphologies. As the vorticity of the applied shear competes with the circling sense of the head, the chirality of the whole complex can be tuned by activity. Our results are relevant to characterize the response of living and artificial chiral active polymer chains to complex flow fields.

A new early actinopterygian from the Mid-Pennsylvanian Logan Quarry Shale member of Indiana

Kalops is a genus of early ray-finned fish in North America. It is distinguished from early actinopterygians by the combination of the following characters: subterminal mouth, rounded oval shaped lacrimal, multiple small supraorbitals and suborbitals. So far, it has been only excavated from the Serpukhovian (Late Mississippian) Bear Gulch Limestone in Montana. Here, a new species of this genus, Kalops loganensis n. sp., is described based on two specimens from the Moscovian Logan Quarry Shales in Indiana. The phylogenetic analysis indicates that the new species is a member of Kalops and recovered as the sister of the other two species, and the genus is recovered as a basal Actinopterygii, as the sister group of some other genera from the Bear Gulch Limestone. This new species is the first record of Kalops outside of Bear Gulch. It provides evidence of survivability of this genus, and as the youngest member, proves that Kalops lived at least through the Mid-Pennsylvanian in North America.

Insights into the special physiology of Mortierella alpina cultured by agar supported solid state fermentation in enhancing arachidonic acid enriched lipid production

Exact constraint of density functional approximations at the semiclassical limit

We introduce the semiclassical limit to electronic systems by taking the limit ℏ → 0 in the solution of Schrödinger equations. We show that this limit is closely related to one type of strong correlation that is particularly challenging from conventional multi-configurational perspective but can be readily described through semiclassical analysis. Furthermore, by studying the performance of density functional approximations (DFAs) in the semiclassical limit, we find that mainstream DFAs have erroneous divergent energy behaviors as ℏ → 0, violating the exact constraint of finite energy. Importantly, by making connection of the significantly underestimated DFA energies of many strongly correlated transition-metal diatomic molecules to their rather small estimated ℏeff, we demonstrate the usefulness of our semiclassical analysis and its promise for inspiring better DFAs.

Manipulating the Isomerization of a Tris-azobenzene Cage by Anion Binding

AAV delivery of GBA1 suppresses α-synuclein accumulation in Parkinson’s disease models and restores functions in Gaucher’s disease models

Biallelic mutations in the glucosylceramidase beta 1 (GBA1) gene are the underlying genetic cause of Gaucher’s disease (GD), resulting in a deficient lysosomal hydrolase and subsequent accumulation of glycosphingolipids. More recently, GBA1 mutations have been identified as the most prevalent genetic risk factor for Parkinson’s disease (PD), associated with more pronounced symptoms characterized by earlier onset and accelerated cognitive decline. In these GBA-associated PD patients the α-synuclein pathology is more prominent, and recent data suggest a link between α-synucleinopathies and GBA1 mutations. Here, we explored the effect of GBA1 gene supplementation on the GD phenotypes and α-synuclein pathology by using the adeno-associated virus (AAV) system. We have compared two AAV serotypes, AAV5 and AAV9, and two different ubiquitous promoters, and demonstrate that both promoters work efficiently albeit not the same in vitro and in vivo. GBA1 overexpression reduces the accumulation of glucosylsphingosine (GlcSph) and restores motor dysfunction in a GD mouse model. We further demonstrate that GBA1 overexpression can dissolve phospho-α-synuclein aggregation induced by the addition of α-synuclein pre-formed fibril (PFF) in a mouse primary neuron model suggesting the direct effect of β-Glucocerebrosidase (GCase) on α-synuclein accumulation. In vivo, we show that GCase inhibition can induce insoluble high-molecular-weight α-synuclein aggregation and that delivery of GBA1 achieves robust reduction of the α-synuclein aggregates in the mouse brain. In summary, GCase expression not only reduces GlcSph, but also restores GD motor dysfunction and removes α-synuclein aggregates which are the hallmark for PD and α-synucleinopathies. AAV delivery of GBA1 is a powerful approach to restore glucocerebrosidase function and to resolve misfolded α-synuclein protein, with applications for GD and PD.

Effects of the mitoxantrone thermosensitive liposome nanodelivery system on prostate cancer in vivo and in vitro

Superfluidity of quasi-2D 4He droplets on graphite

The superfluid response of nanoscale size quasi-2D 4He droplets adsorbed on a graphite substrate is investigated by computer simulations. It is found that clusters comprising as few as 7 atoms are stable at temperatures of ≲0.15 K. Clusters of ∼20 atoms or less are liquid-like and ∼100% superfluid. As the size is increased, the central region crystallizes, forming the commensurate C1/3 phase, with a quasi-1D surface layer of superfluidity possibly evolving into a Luttinger liquid or a transverse quantum superfluid with increasing cluster size. The relevance to quasi-2D molecular spectroscopy is discussed.