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Unveiling the drivers of environmental performance by investigating the Nexus of energy, economic complexity and institutional quality in G7 nations

Fine analysis of the effect of NH3 on the microstructure of mixed KCl and NH4Cl aqueous solutions

In this study, a solution system of KCl–NH4Cl–NH3–H2O with different mass fractions was prepared at room temperature using x-ray scattering, Raman spectroscopy, and molecular dynamics simulations. From x-ray scattering, it was obtained that the peak near Q = 2.50 Å−1 in the F(Q) function changed from a flat-topped blunt peak to a bimodal peak as the concentration of ammonia increased. This change indicated that increased ammonia altered the hydrogen bonding network within the mixed solution. In the G(r) function, the peak near 3.25 Å enhances with the increase in ammonia concentration, suggesting a higher occurrence of N(NH4+)–N(NH3) interactions. Raman spectroscopy findings demonstrated that in the KCl–NH4Cl aqueous mixture, the area of DDAA-type hydrogen bonds increased as KCl concentration decreased and NH4Cl concentration increased. This suggests that KCl disrupts DDAA-type hydrogen bonds more significantly than NH4Cl. The situation was reversed when ammonia was added to the system, implying that KCl damages the DDAA-type hydrogen bonding structure less than NH4Cl when NH3 is present in the solution. Molecular dynamics simulations indicated that the coordination number of K–Cl increases with ammonia concentration, as ammonia’s lone pair of electrons can bind to NH4+ to stabilize the [NH4(H2O)m−n(NH3)n]+ complex. This study elucidates the underlying microscopic mechanisms behind the decrease in KCl solubility and the increase in NH4Cl solubility upon increased ammonia.

Correction: Development and validation of a cardiovascular risk prediction model for Sri Lankans using machine learning

Excited-state structural characterization of a series of nanosecond-lived [Fe(terpy)2]2+ derivatives using x-ray solution scattering

[ F e ( t e r p y ) 2 ] 2 + (terpy = 2,2′:6′,2″-terpyridine) is a transition metal complex where the spin state is photoswitchable and where the properties of the metal-centered quintet excited state (5MC) can be tuned by substituting different electron withdrawing or electron donating groups on the 4′ position of the terpyridine. To better understand the physics determining the photoswitching performance, a deeper insight into the positions of the relevant potential energy surfaces and the molecular structure of the 5MC state is needed. We present a structural investigation based on Time Resolved x-ray Solution Scattering (TR-XSS) by which we determine the average dFe–N bond-length elongation following population of the 5MC state as well as the lifetime of this state in a series of seven modified [Fe(terpy)2]2+ systems in aqueous solution following photo-excitation. The analysis of the TR-XSS data is supported by Density Functional Theory (DFT) and Molecular Dynamics calculations. The quintet state lifetime is determined to vary by more than a factor of 10 (from 1.5 to 16 ns) based on the electron withdrawing/donating properties of the substituting group. Both the DFT calculations and the structural analysis of the experimental data show that the main photo-induced change in metal–ligand bond lengths ΔdFe–N is ∼0.2 Å for all systems.

Modeling spatial and temporal variability in educational development index of Bangladesh using socio-economic, and demographic data, 2001–2021: A Bayesian approach

Background The Educational Development Index (EDI) is a critical tool for assessing and tracking the progress of education systems from local to national, and even global scales and needs to be chosen for every layer of the subnational boundaries to secure the basic human rights of the people. In reality, there are significant variations within the consecutive time breaks and the geographical boundaries that need to be examined. The authors aim to examine how the EDI relates to various spatiotemporal variables. Methods and Materials This research is based on secondary data on literacy rates (EDI) from 64 districts of Bangladesh and 6 relevant variables over the period 2001 to 2021. The optimal model for the data was identified from Bayesian spatial-temporal modeling (Linear, Analysis of Variance (ANOVA), Autoregressive (AR1), and AR2) and the Markov Chain Monte Carlo (MCMC) method used to generate data about the prior and posterior realizations. To select the best model different model selection and validation criteria such as the Deviance Information Criterion (DIC), Watanabe-Akaike information criterion (WAIC), and Root Mean Square Error (RMSE) were employed in this study. Results The ‘AR1’ model is a ‘temporal model’ performed better than others. Significant spatial (ρS=0.994) and temporal (ρT=0.347) variations were identified for the suited model. Of the factors considered for model fitting, the health index, income index, expected years of schooling, population density, and dependency ratio are found to be important components of educational development in Bangladesh. Conclusion The variation in the spatial domain can be used to identify the districts to improve the educational index controlling responsible factors by the policymakers.

Low-temperature nucleation rate calculations using the N-Fold way

We present a numerical study to determine nucleation rates for magnetization reversal within the Ising model (lattice gas model) in the low-temperature regime, a domain less explored in previous research. To achieve this, we implemented the N-Fold way algorithm, a well-established method for low-temperature simulations, alongside a novel, highly efficient cluster identification algorithm. Our method can access nucleation rates up to 50 orders of magnitude lower than previously reported results. We examine three cases: homogeneous pure system, system with static impurities, and system with mobile impurities, where impurities are defined as sites with zero interactions with neighboring spins (the spin value of impurities is set to 0). Classical nucleation theory holds across the entire temperature range studied in the paper, for both the homogeneous system and the static impurity case. However, in the case of mobile impurities, the umbrella sampling technique appears ineffective at low mobility values. These findings provide valuable insights into nucleation phenomena at low temperatures, contributing to theoretical and experimental understanding.

PLANES: Plausibility analysis of epidemiological signals

Methods for reviewing epidemiological signals are necessary to building and maintaining data-driven public health capabilities. We have developed a novel approach for assessing the plausibility of infectious disease forecasts and surveillance data. The PLANES ( PL ausibility AN alysis of E pidemiological S ignals) methodology is designed to be multi-dimensional and flexible, yielding an overall score based on individual component assessments that can be applied at various temporal and spatial granularities. Here we describe PLANES, provide a demonstration analysis, and discuss how to use the open-source rplanes R package. PLANES aims to enable modelers and public health end-users to evaluate forecast plausibility and surveillance data integrity, ultimately improving early warning systems and informing evidence-based decision-making.

Construction of high-performance sodium ion hybrid capacitors based on MXene surface modulation and electrolyte matching

Sodium-ion hybrid capacitors have garnered significant attention due to their high power and energy densities, as well as the abundance of sodium reserves. However, the mismatch between anode and cathode dynamics is the biggest barrier to improving their performance. To address this issue, we propose a strategy for the preparation of porous MXene by hydrogen peroxide (H2O2)-controlled etching to solve the capacity degradation and ion diffusion limitation, which are caused by van der Waals forces between MXene nanosheets. This approach facilitates the realization of three-dimensional ion channels with both vertical and horizontal pathways, significantly enhancing the availability of active sites and improving the ion diffusion rate. By adjusting the amount of oxidant, porous MXene (P-MXene-2) with an optimal pore size range was obtained. The assembled half-cell has a capacity of 180 mAh g−1 at a rate of 0.05 A g−1. Furthermore, by combining a porous carbon cathode with porous MXene and electrolyte screening, a SIHC with a high energy density of 110.6 Wh kg−1 at 1000 W kg−1 and 71.1 Wh kg−1 at 20 kW kg−1 was successfully constructed. This study provides useful insights into the design and preparation of porous MXene electrodes and their energy storage applications.

Immunosuppressive drugs and diet interact to modify the gut microbiota and cardiovascular risk factors, and to trigger diabetes

Background Kidney transplant recipients are prescribed an immunosuppressive therapy (IST) and some of them follow a high fat diet (HFD) despite medical recommendations. Both are frequently associated with gut microbiota changes and metabolic disorders. We aimed at precisely identifying the effect of the IST and the HFD on metabolic parameters and the gut microbiota in mice, and at establishing correlations between the latters. Methods 8-week-old male mice were treated with IST (a combination of prednisone, mycophenolate mofetil and tacrolimus) or not and were fed HFD or standard chow. Metabolic parameters were measured, and the gut microbiota was explored by the quantification of specific bacterial groups by qPCR and by 16S rDNA sequencing. Results The HFD increased insulinemia and decreased the fecal proportion of Bacteroidetes and of Bacteroides. The IST increased systolic blood pressure and the fecal proportion of Escherichia coli. The HFD and the IST administered together resulted in an additive effect on glucose intolerance, high fasting blood glucose, homeostasis model assessment of insulin resistance (HOMA-IR), percentage of fat mass, blood triglyceride, blood cholesterol, and endotoxemia. On the opposite, the HFD and the IST had antagonistic effects on body weight, the proportion of Firmicutes, the Firmicutes/Bacteroidetes ratio, and the proportion of Clostridium leptum, Bifidobacterium, and Lactobacillus in the feces. Finally, we found that the correlations between gut bacterial communities and metabolic consequences of the HFD were altered by the IST. Conclusion The IST and the HFD have specific consequences on the gut microbiota and metabolism. We hypothesize that the metabolic consequences are at least partially mediated by IST/HFD-induced dysbiosis.

Electron correlation in benzene: A QMC study of neutral and charged states

In this paper, we employ variational Monte Carlo and fixed-node diffusion Monte Carlo (FN-DMC) methods to investigate electron correlation effects in neutral and charged benzene molecules. Using orbitals from Hartree–Fock (HF) and density functional theory calculations, FN-DMC with the frozen-core approximation yields correlation energies consistent with CCSD(T) and ph-AFQMC, while all-electron FN-DMC lowers the correlation energy by ∼0.27 a.u., highlighting the role of core-electron contributions. On average, all-electron FN-DMC predicts vertical [VIP: 0.3477(34) a.u.] and adiabatic [AIP: 0.3433(39) a.u.] ionization potentials, both slightly above the experimental value [0.339 70(2) a.u.]. Zero-point vibrational energy (ZPVE) corrections adjust the VIP and AIP by −0.012 and +0.0037 a.u., respectively, improving agreement with experiment. Compared to HF, FN-DMC incorporates an additional 0.055 a.u. (≈1.5 eV) of correlation energy into the IP, demonstrating its effectiveness in capturing electron correlation in aromatic systems.

Evaluating the accuracy of ICD-10 codes for syncytial respiratory virus diagnosis in hospitalized patients: A record-linkage study (2022–2023)

Background Respiratory Syncytial Virus (RSV) is a leading cause of severe respiratory infections in young children and older adults. Accurate RSV surveillance is essential to understanding its disease burden and evaluating vaccine impact. Methods We assessed the accuracy of ICD-10 coding for RSV hospitalizations in the Brazilian Hospital Information System (SIH) by linking it with the Severe Acute Respiratory Syndrome (SIVEP) notification system (2022–2023). Laboratory-confirmed RSV-positive and RSV-negative cases in SIVEP were used as the reference standard. Sensitivity and specificity were evaluated for ICD-10 definitions (RSV, RSV +  J21 [Acute Bronchiolitis], RSV +  Acute Respiratory Infection) overall and by age group (under 1 year, under 5 years, and over 60 years). The top 10 diagnoses of RSV-positive patients were also analyzed by age group. Results Among 15,169 RSV-positive patients linked to an SIH record, 73.0% were under 12 months old, 20.8% were 1-5 years old, 3.7% were 5-59 years old, and 2.5% were 60 + years. Acute bronchiolitis was the most common diagnosis overall (43.5%), particularly in infants (53.5%). In older adults, pneumonia due to unspecified microorganisms was most frequent (24.6%). Sensitivity improved with broader case definitions, such as, RSV +  Acute Respiratory Infection (66.7%, 95%CI: 65.8–67.6 in infants; 23%, 95%CI: 18.9–27.6 in older adults). Specificity was higher in older adults (83.8%, 95%CI: 83.5–84.1) than in infants (45.1%, 95%CI: 44.4–45.6). Additionally, 40,701 RSV-positive notified cases lacked RSV-coded diagnoses in SIH. Conclusion Our study highlights the discrepancy between RSV-positive cases identified in SIVEP and those coded in the SIH database, reflecting limitations in ICD-10 coding, particularly in the older population. Reliance on symptomatic coding rather than confirmed diagnoses contributes to this issue. Accurate RSV identification is crucial, especially with new vaccines available. Improved diagnostic coding is essential for effective RSV surveillance and evaluating vaccine impact.

Impact of iodine-substitution on the symmetry and room-temperature phosphorescence behavior of thienyl diketone skeleton

Introducing heavy atoms, or replacing atoms with heavier ones, is a routine approach for accelerating spin-flipping photophysical processes. However, predicting its impact on phosphorescence efficiency is not straightforward. Herein, we report an unexpected consequence of bromine-to-iodine substitution in a bromothienyl diketone derivative, TIPS-BrTn, that exhibits outstanding room-temperature phosphorescence (RTP) in cyclohexane solution. Contrary to our expectation, the iodo-congener TIPS-ITn exhibited feeble photoluminescence, which we confirmed as RTP by ultrafast spectroscopy. Further experimental and theoretical studies revealed that, in the T1 state, an excited-state symmetry breaking occurred on TIPS-ITn while TIPS-BrTn preserved the centrosymmetric geometry. We identified the driving force for the symmetry breaking as an intramolecular two-center three-electron bonding interaction between iodine and carbonyl oxygen in the (n,π*) excited state. Consequently, while the direct T1–S0 spin–orbit coupling (SOC) in TIPS-BrTn is symmetry-forbidden and zero, that of TIPS-ITn is non-zero due to the loss of centrosymmetry, thereby accelerating nonradiative T1–S0 decay to diminish the RTP. Importantly, the phosphorescence rate constant is not solely dictated by the direct T1–S0 SOC; instead, it can be rationalized by the intensity borrowing from higher singlet states. Thus, our work highlights the importance of controlling molecular symmetry, which could suppress the direct T1–S0 SOC and lead to a preferential acceleration of radiative decay over nonradiative decay for achieving efficient RTP.

Metabolic improvement after exercise training in children with obesity: Possible role of the six-minute walking test

The aims of this study are to evaluate the effectiveness of an online supervised training program in modulating lipid and glucose metabolism in children with obesity and to investigate the possible role of the 6-minute walking test (6MWT) as a predictor of metabolic improvement. A total of 35 Caucasian children with obesity (aged 8-13) were enrolled in the study and tested before (T0) and after (T1) a 12-week online supervised exercise training protocol: cardiovascular fitness (by means of 6MWT), metabolic biochemical profile, lifestyle (with ad hoc questionnaires focusing on physical activity, nutrition, sedentariness, sleep hours and quality, health perception) and Cardiac Autonomic Regulation (CAR) were assessed. Spearman correlations between the variations in the studied outcomes were explored. After intervention, the distance covered during 6MWT significantly increased (p < 0.001), and nutrition quality improved slightly but significantly (p = 0.03). The improvement in the 6MWT performance was shown to be significantly correlatee with the reduction of insulin levels (r = -0.455; p = 0.02), HOMA-IR Index (r = -0.452; p = 0.02), total cholesterol values (r = -0.549; p = 0.004) and Atherogenic Index of Plasma (AIP) (r = 0.422; p = 0.04). Moreover, there was a significant correlation between the improvement in 6MWT and health perception (r = 0.578; p = 0.002). We observed that the improvement in the 6MWT performance correlates with better metabolic profile after exercise training in children with obesity suggesting the goodness of this simple test on unveil changes in pathogenetic processes underlying obesity.

Ehrenfest dynamics with localized atomic-orbital basis sets within the projector augmented-wave method

Density functional theory with linear combination of atomic orbitals (LCAO) basis sets is useful for studying large atomic systems, especially when it comes to computationally highly demanding time-dependent dynamics. We have implemented the Ehrenfest molecular dynamics (ED) method with the approximate approach of Tomfohr and Sankey within the projector augmented-wave code GPAW. We apply this method to small molecules as well as larger periodic systems and elucidate its limits, advantages, and disadvantages in comparison with the existing implementation of Ehrenfest dynamics with a real-space grid representation. For modest atomic velocities, LCAO-ED shows satisfactory accuracy at a much reduced computational cost. This method will be particularly useful for modeling ion irradiation processes that require large amounts of vacuum in the simulation cell.

Correction: Effects of Yersinia pseudotuberculosis outer membrane vesicles on Pseudomonas aeruginosa antigens immune response

Molecular dynamics simulations for enzymatic hydride-transfer reactions: Defining environmental reaction coordinates to capture transition state diversity

It is now well established that the transition state of a chemical reaction is not a single, static structure but rather a distribution of configurations. However, the implications of this distributed nature remain incompletely characterized, particularly for quantum proton and hydride transfer reactions, where variations in donor–acceptor separations at the transition state are key: they can determine whether or not tunneling contributes to the transfer. Consequently, the transition state’s characterization critically depends on the chosen reaction coordinate, and several geometry-based and energy-based coordinates have been proposed for empirical valence bond and hybrid QM/MM molecular dynamics simulations of such reactions. Here, we systematically evaluate these coordinates, using a general analytic model for proton- and hydride-transfer reactions alongside important aspects of the enzymatic hydride transfer in formate dehydrogenase as a case study. Our analysis reveals significant limitations of common geometry-based and vertical energy gap coordinates, which often fail to isolate environmental effects and can bias the description of transition states. To address these issues, we propose an equilibrium energy difference coordinate that excludes the rapid fluctuations of the transferring quantum proton or hydride, focusing instead on the environment’s polarization. Additionally, we demonstrate that the broad distribution of transition state configurations implies that key reaction properties, such as rate constants and kinetic isotope effects, may not always report on the same subset of transition state configurations. This insight helps resolve some mechanistic ambiguities and highlights the importance of carefully selecting reaction coordinates for simulating reaction dynamics (especially for quantum particle transfers) in enzymatic and condensed-phase chemistry.

Extraordinary siblings: Mole rats, marmosets, and Radcliffe-Brown

According to the theory of kin selection, an organism that shows some level of altruism toward her kin – lowering her own fitness, raising that of a close genetic relative – may enjoy an evolutionary advantage. Some species show beyond-ordinary altruism toward siblings, and other kin, owing to unusual reproductive biology and/or ecology. Human beings are exceptional in another way: how we treat our kin depends partly on how we feel about them, but also partly on socially enforced norms. This article explores several versions of a simple evolutionary game, the Brothers Karamazov Game, that departs from the standard theory of kin selection to allow for the distinctively human capacity for establishing and enforcing social norms. We discuss possible applications to understanding the “unity of the sibling group” (Radcliffe-Brown) – according exceptional treatment to siblings, and to relatives classified as siblings or linked through siblings. We give special attention to lowland South America, where the sibling relationship is central to social organization.

Trajectory-based non-adiabatic simulations of the polariton relaxation dynamics

We benchmark the accuracy of various trajectory-based non-adiabatic methods in simulating the polariton relaxation dynamics under the collective coupling regime. The Holstein–Tavis–Cummings Hamiltonian is used to describe the hybrid light–matter system of N molecules coupled to a single cavity mode. We apply various recently developed trajectory-based methods to simulate the population relaxation dynamics by initially exciting the upper polariton state and benchmark the results against populations computed from exact quantum dynamical propagation using the hierarchical equations of motion approach. In these benchmarks, we have systematically varied the number of molecules N, light–matter detunings, and the light–matter coupling strengths. Our results demonstrate that the symmetrical quasi-classical method with γ correction and spin-mapping linearized semi-classical approaches yield more accurate polariton population dynamics than traditional mixed quantum-classical methods, such as the Ehrenfest and surface hopping techniques.

A quality improvement initiative to increase HIV post-exposure prophylaxis treatment for emergency department patients after sexual assault: A pre-post study

Background Many emergency department (ED) patients after a sexual assault face barriers to receiving HIV post-exposure prophylaxis (PEP). We implemented a quality improvement initiative which updated the sexual assault electronic health record (EHR) template and made available free, full-course PEP treatment packs for use at provider discretion. The aim of this study was to compare the receipt of HIV PEP for ED patients receiving sexual assault care before and after the initiative. Methods This was a retrospective, quasi-experimental, pre-post study of all ED patients who completed a sexual assault examination between June 1, 2022 – January 31, 2023 (pre-intervention) and March 1, 2023 – October 31, 2023 (post-intervention). An odds ratio (OR) and 95% confidence interval (CI) were calculated to determine the initiative’s effect on PEP prescribing. Multivariable logistic regression models estimated the independent effect of the initiative while controlling for potential confounders. Results Of the 235 sexual assault examinations, 117 (49.8%) were during the pre-intervention and 118 (50.2%) were during the post-intervention periods. Pre-intervention, the mean age was 33.0 years (standard deviation [SD] 12.3), 94.0% were female, 30.8% Black, 31.6% Latinx, and 28.2% White. Post-intervention, the mean age was 29.2 years (SD 12.6), 90.7% were female, 42.4% Black, 28.8% Latinx, and 17.8% White. Patients were more likely to receive HIV PEP post-intervention (33/118, 28.0%) than pre-intervention (11/117, 9.4%) (OR 3.7, 95% CI 1.8 to 7.8). The independent effect of the initiative on HIV PEP prescribing remained significant after controlling for demographics (OR 3.6, 95% CI 1.6 to 8.0), assault characteristics (OR 4.2, 95% CI 1.6 to 11.1), and provider experience (OR 3.5, 95% CI 1.7 to 7.5). Conclusion The availability of HIV PEP treatment packs plus a modification to the EHR template led to a significant increase in the provision of HIV PEP for ED patients after sexual assault.

Deciphering the structural code for the face-centered-cubic ligand protected intermetallic AuAg nanoclusters

The incorporation of Ag atoms into ligand-protected gold nanoclusters is an effective way to tune their properties for applications in optics, electronics, and catalysis. However, the precise identification of preferred doping sites is challenging owing to its high structural complexity, which hinders establishing the structure–activity relationship. Here, through density functional theory calculations coupled with energy evaluation, delicate structural analysis, valence electron counting, and localized molecular orbital topology, we characterize the tetrahedral Au3Ag with closed-shell two valence electrons [Au3Ag(2e)] as a fundamental building block in face-centered-cubic (FCC) ligand-protected AuAg (LP-AuAg) alloy nanoclusters. The kernel structures of FCC LP-AuAg alloy clusters are constructed by rational spatial packing of Au3Ag(2e), Au4(2e), and Au3(2e) blocks, aligning with the grand unified model of ligand-protected Au nanoclusters. In addition, we predict 40 FCC LP-AuAg alloy nanoclusters with 141 low-energy isomers. This work underscores the crucial role of subset blocks in stabilizing the entire cluster and provides valuable insights into the structural features of FCC LP-AuAg alloy clusters.