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Associated factors, triggers and long-term outcome in Complex Regional Pain Syndrome (CRPS) in the upper limb – A descriptive cross-sectional study
The pathophysiology behind Complex Regional Pain Syndrome (CRPS) is not fully understood and associated factors and triggers for developing the condition are debated. We aimed to study such factors and long-term outcome in a descriptive cross-sectional study with a well-defined population with CRPS in the upper limb and related to sex and CRPS type. In retrospectively collected data from medical records, 149 subjects [women n = 104 (70%); type 1 CRPS, n = 108 (72%); type 2 CRPS, n = 41 (28%); follow-up time 21 [8-43] months] were identified and analysed (Chi-squared test, Mann-Whitney U-test, and multiple linear regression). A majority were manual workers, and a larger proportion of subjects were smokers and had less post-secondary education than a reference population (p < 0.001 and p < 0.008). Men were younger, more frequently smoked, had higher BMI, and had lower education levels than women (p = 0.044, p = 0.007, p < 0.001, and p = 0.016, respectively). Subjects with CRPS type 2 were younger and had a longer time from symptoms until diagnosis, longer follow-up time, and more follow-up visits, indicating worse outcome (p = 0.016, p = 0.0012, p = 0.003, and p = 0.004, respectively). Among CRPS, 32% had a prior pain disorder and 7% had previously visited a pain management clinic. While there was no significant difference in mental illness occurrence before CRPS diagnosis compared to a reference population, mental illness increased by 76% after diagnosis. Factors such as CRPS type 2, older age, and delayed diagnosis were associated with longer follow-up periods. Additionally, 45% were on sick leave for over 12 months, and 20% were permanently unable to work. Socioeconomic deprivation is an associated factor in developing CRPS, in which a variety of triggers exist. Subjects with CRPS, particularly type 2, are at high risk of severe remaining symptoms, including mental illness and risk of never returning to work.
Heteroatom decorated C2N monolayer for gas-sensing application: Insight from first-principles
Development of novel gas-sensing materials is essential to high-performance gas sensors for monitoring target gases in industrial production and environmental protection. Herein, we investigate two types of the heteroatom-decorated C2N monolayer, denoted as M@C2N (M = Mn and Ni) and B-C2N, for their gas-sensing functionality toward seven small gaseous molecules (H2, O2, N2, CO, CO2, NH3, and H2O). The key gas-sensing characteristics concerning chemiresistive (CR) and field-effect transistor (FET) gas sensing have been thoroughly explored. The results show that Mn@C2N and Ni@C2N can work as either CR or FET gas-sensing materials for detecting H2, O2, N2, CO, CO2, NH3, and H2O, whereas B-C2N can work as a disposable gas sensor for O2, H2O, and NH3. Mn@C2N and Ni@C2N are the most selective toward O2 and NH3, followed by CO and H2O in an oxygen- and ammonia-free environment, while B-C2N is the most selective toward H2O and NH3. More importantly, the adsorption strength of target molecule plays a critical role in gas-sensing mechanism as well as selectivity, recovery time, and sensitivity. This study offers theoretical perspectives on 2D hybrid carbon-based nanomaterials for efficient gas sensing.
Role of aspirin on colorectal cancer risk and bacterial translocation to bloodstream
An involvement of gut microbiota on the possible role of aspirin against intestinal adenoma (IA) and colorectal cancer (CRC) has been suggested. To further investigate this issue, we analyzed data from an Italian case-control study including 100 incident histologically confirmed CRC cases, as well as 100 IA and 100 controls without lesions from colonoscopy, matched to cases by center, sex and age. Serum zonulin was assessed by ELISA kit and blood bacterial DNA by qPCR and 16S rRNA gene profiling. Fifty-eight subjects (19.3%) reported aspirin use of ≥ 100 mg/day for cardiovascular prevention for at least six months. To evaluate the relationship between aspirin and IA and CRC risks, the odds ratios (OR) of IA and CRC and the corresponding 95% confidence intervals (CI) for aspirin use were estimated using a logistic regression model conditioned on the matching variable and adjusted for education and a model adjusted for several potential confounders including BMI and cardiovascular diseases. We evaluated whether the levels of zonulin and bacterial DNA data were different in aspirin users vs non-users through the rank sum and chi-square tests. Aspirin use was associated with a reduced risk of IA (OR = 0.45, 95% CI = 0.21-0.94) and CRC (OR = 0.43, 95% CI = 0.19-0.96). Similar results were obtained using the fully adjusted model. We found lower genera and operational taxonomic units (OTUs) richness of blood bacterial community in aspirin users vs non-users overall and in cases and controls. The genera Cutibacterium, Sphingomonas, Gaiella, Delftia and Romboutsia, order Microtrichales and class Deltaproteobacteria were different according to aspirin use. This study provides additional data on the favorable role of aspirin on IA and CRC risks and supports the hypothesis of an involvement of intestinal bacterial translocation to the bloodstream.
Transient absorption and anisotropy studies of a push–pull azo derivative with an isomerization path-selective local minimum in the ground state
The ultrafast excited-state dynamics of the E and Z isomers of a push–pull nitroazobenzene containing an octupolar bis(4′-tert-butylbiphenyl-4-yl)aminophenyl electron donor group were studied with transient absorption (TA) and TA anisotropy. A comprehensive study with two excitation wavelengths and a broadband white-light continuum probe (400–1400 nm) has determined that a torsional isomerization mechanism is the most probable for both isomers. This has shed light on the excited state behavior of the elusive push–pull Z isomer, which has its properties mostly predicted by simulations and systematically lacks experimental observations. Meanwhile, another unproductive relaxation pathway, associated with a symmetric bending motion, was found only for the E isomer. When relaxing through this pathway, the molecule encounters a potential barrier in the ground state, which requires significant structural reorganization before full relaxation. This local minimum can be more general than expected and may be behind unsolved issues in the literature of azobenzenes.
Effect of pyrroloquinoline quinone on skin aging in Bmi-1 KO mice and underlying mechanisms
To investigate the effect of pyrroloquinoline quinone (PQQ) on skin aging in the Bmi-1 KO mice and its underlying mechanisms, we administered a normal diet to both Wild type mice (WT) and Bmi-1 KO mice, while supplementing the diet of Bmi-1 KO mice with PQQ (PQQ+Bmi-1 KO). Subsequently, we compared the thickness of the skin epidermis, dermis, pilosebaceous unit and collagen ratio using HE staining and Masson’s trichrome. Additionally, immunohistochemical staining, Western blotting and electron microscopy were applied across all three groups. The results revealed that Bmi-1 KO mice exhibited premature aging phenotypes compared to the WT group; however, PQQ administration effectively delayed premature aging in Bmi-1 KO mice. Furthermore, reduced epidermal thickness, dermal thickness, pilosebaceous units count as well as collagen ratio were observed in Bmi-1 KO mice. Moreover, the PCNA positive cell percentage also decreased in Bmi-1 KO mice. Conversely, treatment with PQQ significantly increased epidermal thickness, dermal thickness, pilosebaceous unit count, collagen ratio and PCNA positive cell percentage when compared to Bmi-1 KO mice. In order to further investigate the anti-aging mechanism of PQQ, experiments have revealed that PQQ effectively suppressed the expression of cell cycle proteins p16, p19, and p53 in Bmi-1 KO mice. In addition, autophagy-related experiments demonstrated that compared to the WT group, Bmi-1 KO mice exhibited an increased number of autophagosomes along with decreased expression of Beclin-1 and LC3Ⅱ/LC3Ⅰratio, and increased expression of p62. However, supplementation with PQQ resulted in a reduction in the number of autophagosomes while increasing the expression of Beclin-1 and LC3Ⅱ/LC3Ⅰratio and decreasing the expression of p62. This study provides evidence that downregulation of Bmi-1 promotes skin aging, whereas PQQ delays skin aging in Bmi-1 KO mice by promoting cell proliferation, inhibiting the expression of p16, p19 and p53 and enhancing autophagy levels.
Understanding dynamics in coarse-grained models. V. Extension of coarse-grained dynamics theory to non-hard sphere systems
Coarse-grained (CG) modeling has gained significant attention in recent years due to its wide applicability in enhancing the spatiotemporal scales of molecular simulations. While CG simulations, often performed with Hamiltonian mechanics, faithfully recapitulate structural correlations at equilibrium, they lead to ambiguously accelerated dynamics. In Paper I [J. Jin, K. S. Schweizer, and G. A. Voth, J. Chem. Phys. 158(3), 034103 (2023)], we proposed the excess entropy scaling relationship to understand the CG dynamics. Then, in Paper II [J. Jin, K. S. Schweizer, and G. A. Voth, J. Chem. Phys. 158(3), 034104 (2023)], we developed a theory to map the CG system into a dynamically consistent hard sphere system to analytically derive an expression for fast CG dynamics. However, many chemical and physical systems do not exhibit hard sphere-like behavior, limiting the extensibility of the developed theory. In this paper, we aim to generalize the theory to the non-hard sphere system based on the Weeks–Chandler–Andersen perturbation theory. Since non-hard sphere-like CG interactions affect the excess entropy term as it deviates from the hard sphere description, we explicitly account for the extra entropy to correct the non-hard sphere nature of the system. This approach is demonstrated for two different types of interactions seen in liquids, and we further provide a generalized description for any CG models using the generalized Gaussian CG models using Gaussian basis sets. Altogether, this work allows for extending the range and applicability of the hard sphere CG dynamics theory to a myriad of CG liquids.
Correction: Detection and recognition of foreign objects in Pu-erh Sun-dried green tea using an improved YOLOv8 based on deep learning
Thermostatting nonequilibrium systems: A thermal energy constraint for systems under directive perturbations
This paper brings attention back to discussions about the use of equilibrium thermostats for nonequilibrium molecular dynamics simulations. It argues that, due to the fluctuation–dissipation theorem, the justification for using equilibrium thermostats for nonequilibrium simulations is inherited only by cases in which the perturbation is small enough for the perturbed system to behave like the unperturbed equilibrium system. In the process, this paper categorizes models of external perturbations in molecular dynamics as either responsive—i.e., perturbations that impose a force—or directive—i.e., perturbations that impose a trajectory. Since directive perturbations have not been studied enough in the literature but are becoming more relevant, their effects on simple perturbed thermostatted systems are considered. Finally, using a perturbed two-point harmonic oscillator as well as a driven particle immersed in a simple Lennard-Jones fluid, it gives an approximation for the limit of justified equilibrium thermostat use for perturbed systems. This paper hopes to inspire further research in the fields of nonequilibrium statistical mechanics and nonequilibrium molecular dynamics.
The influence mechanism of planned behavior and self-consciousness on learners’ willingness to use language learning Apps: Validation based on structural equation modeling
The continuous development of digital technology facilitates the informatization of foreign language learning, making it possible to create a deeply integrated mobile learning environment which is conducive to enhancing learning efficiency. To investigate learners’ willingness to use mobile language leaning applications (Apps), this research is carried out under an extended theoretical framework of Technology Acceptance Model (TAM) and Theory of Planned Behavior (TAM) by incorporating self-consciousness. On the basis of the survey data of 728 college students, structural equation modeling is constructed and empirically tested with AMOS 23.0. Results show that the structural equation modeling based on the extended TAM-TPB framework is suitable for analyzing the influencing mechanism of learners’ willingness to use language learning Apps. College students’ willingness to use language learning Apps is directly affected by behavioral attitudes, subjective norms, and perceived behavior control. Perceived ease of use has a significant direct impact on perceived usefulness. However, perceived ease of use and perceived usefulness have different mediating effects on learners’ willingness to use language learning Apps through behavioral attitudes, subjective norms, and perceived behavior control. Based on the findings, this paper suggests that when developing language learning Apps, emphasis should be laid on the positive feedback of learners’ self-consciousness and user enjoyment, as well as the construction of a curriculum system centered on core competencies so as to enhance learners’ willingness to use language learning Apps, thereby promoting language learning efficiency.
Erratum: “Inference of Onsager coefficient from microscopic simulations by machine learning” [J. Chem. Phys. 162, 034901 (2025)]
Genome-wide association and selection studies for pod dehiscence resistance in the USDA soybean germplasm collection
As a domestication trait, pod dehiscence has a pleiotropic effect on agronomic traits and significantly contributes to yield loss in soybean. Population studies are still required to comprehend the genetic basis of dehiscence and to develop pod dehiscence-resistant cultivars with the optimal haplotype, thereby improving soybean production. We collected data for one wild (Glycine soja) (G. soja) and four cultivated (Glycine max) (G. max) populations from the USDA database. The G. max populations were evaluated in multi-environment conditions and used for genome-wide association study (GWAS) and selection. GWAS captured 86 quantitative trait loci (QTLs). Seventy-four new QTLs were colocalized in two different G. max populations, and 12 QTLs were closely mapped with previously reported QTLs. Eight out of 86 QTLs were associated with the domestication of pod dehiscence. We implemented marker-assisted selection (MAS) and genomic selection (GS) approaches to select pod dehiscence-resistant accessions with the best haplotype and lowest genomic breeding value (GBV), respectively. While our findings could be utilized for biology, genetics, and plant breeding, selecting pod dehiscence-resistant cultivars with the optimal haplotype will need further studies to confirm additional QTLs and assess advanced GS models.
Comment on “Third density and acoustic virial coefficients of helium isotopologues from <i>ab initio</i> calculations” [J. Chem. Phys. 160, 244305 (2024)]
The impact of brominated flame retardants exposure on serum total bilirubin: A cross-sectional analysis
Background Brominated flame retardants (BFRs) are harmful, bioaccumulative, and persistent environmental pollutants, posing significant health risks. Elevated bilirubin levels can cause neurotoxicity and damage to the heart, liver, kidneys, and other organs. This study utilizes National Health and Nutrition Examination Survey (NHANES) data to investigate the association between exposure to BFRs and total bilirubin (TB) levels in adult participants. Methods Based on data from the NHANES 2007-2016, TB levels were divided into tertiles. Spearman’s rank correlation was used to analyze the relationship between individual BFRs and TB levels. Weighted linear regression analysis, restricted cubic splines (RCS), and stratified analysis were conducted to assess the correlation between individual BFRs and TB levels. Weighted quantile sum (WQS) regression and quantile-based g-computation (QGC) analysis were used to comprehensively evaluate the impact of BFRs exposure on serum TB levels. Results The study included 5831 participants. The results showed that PBB153, PBDE17, PBDE47, PBDE85, PBDE99, PBDE100, PBDE209, and PBDE183 were significantly correlated with TB levels (p < 0.05), with PBDE183 having the highest Spearman rank correlation coefficient of 0.292. After adjusting for confounding factors, most BFR remained significantly positively correlated with TB, while PBDE153 (β: - 0.031, 95%CI: - 0.317, 0.255, p = 0.829) and PBDE66 (β: 0.285, 95%CI: - 0.208, 0.777, p = 0.253) were not statistically significant. RCS analysis indicated that PBDE153 concentration had a significant U-shaped correlation with TB (p < 0.05), while PBDE17, PBDE99, PBDE154, and PBDE209 had an inverted “J”-shaped correlation (p < 0.05). PBB153, PBDE66, PBDE85, and PBDE183 also exhibited significant nonlinear S-shaped correlations with TB (p < 0.05). After stratification by age and gender, most individual BFR remained significantly positively correlated with TB levels (p < 0.05). WQS regression and QGC analysis indicated that mixed BFRs exposure was positively correlated with TB levels (β: 0.553, 95%CI: 0.384, 0.722, p < 0.001 and β: 1.060, 95%CI: 0.587, 1.532, p < 0.001), with PBDE183 contributing the most. Conclusions BFRs exposure is significantly positively correlated with TB levels, further suggesting the potential health impact of BFRs exposure on humans.
Theoretical approach to the crystal structure of poly(butylene 2,5-furandicarboxylate) as revealed by density functional theory
In this work, we present a new model of the crystalline structure of the poly(butylene 2,5-furandicarboxylate) (PBF). This new structure has been derived using an ab initio density functional theory methodology and focusing on the agreement between the experimental and theoretical x-ray diffraction patterns. An extensive study has been performed to analyze the possible conformations that the polymeric strand can adopt in its crystalline form, leading to 60 initial crystalline structures. Due to thermal motion, which cannot be easily tackled with the ab initio methodology, and small inaccuracies, which are intrinsic to this calculation method, the theoretical unit cell dimensions can slightly differ from those obtained in the crystallization experiments. Thus, a structural refinement method has been employed to overcome these discrepancies and procure a crystalline structure whose x-ray diffraction pattern is consistent with the experimental one. For the proposed crystalline structure of PBF, both the powder diffraction pattern and the fiber diffraction diagram show a remarkable agreement with those available in the literature.
Association between timing of exanthema subitum and febrile seizures: The Japan environment and children’s study
Recently, episodes of exanthema subitum (ES) have been occurring later than expected in Japanese patients, though the effects of this delayed timing remain unclear. Therefore, this study examined the association between ES timing and febrile seizure (FS) in Japanese children. Information on the diagnoses of ES and FS was obtained from the Japan Environment and Children’s Study, a nationwide prospective birth cohort study including 97,410 mothers and their children. Two groups were created: early ES (first ES episode between birth and 11 months of age) and late ES (first ES episode between 12 and 23 months of age) groups. Multivariate logistic regression analyses were performed to compare the cumulative incidence rate of FS between the groups. Moreover, because a single episode of fever implies that the ES and FS occurred simultaneously, we examined the association between the ES timing and the simultaneous co-occurrence of FS with ES in a limited cohort with one fever episode until the age of 24 months. In total, 27,238 full-term children were included, with 12,565 (46.1%) in the early ES group and 14,673 (53.9%) in the late ES group. Late ES was estimated to increase the cumulative incidence risk of FS until the age of 24 months (adjusted odds ratio 1.46; 95% confidence interval [1.32–1.61]) and 48 months (1.26 [1.15–1.37]). The limited cohort included 1,022 children, and late ES was estimated to increase the risk of FS with ES (4.39 [1.48–13.02]). Late ES is estimated to increase the risk of FS. Further basic research and cohort studies, including virological examinations, are required to elucidate the pathogenesis of ES with FS.
Primitive and non-primitive model electrolytes: Comparing ion-related Helmholtz energies using molecular simulations
Two main frameworks are commonly used to describe electrolyte solutions: the non-primitive model, which rigorously accounts for all interactions between ions and solvent molecules; and the primitive model, which treats the solvent as a dielectric continuum, only describing ion–ion interactions explicitly. The primitive model offers simple Helmholtz energy expressions, including the Debye–Hückel (DH) equation, the primitive mean spherical approximation (MSA), and the Born theory of solvation. In this work, we evaluate the accuracy of primitive model approaches by comparing their Helmholtz energies with data from molecular simulations obtained for non-primitive model electrolyte solutions. We model electrolyte solutions as mixtures of equally sized, charged, and (non-polarizable) dipolar Lennard-Jones particles. Using thermodynamic integration, we isolate the Helmholtz energy contributions related to solvent–solvent, ion–solvent, and ion–ion interactions. Molecular simulations are performed across two temperatures and two densities, a range of charges, dipole moments, and ion mole fractions (0.005 ≤ xions ≤ 0.05). Our results show that while the primitive model expressions provide a qualitatively reasonable description of electrolyte solutions, they systematically underestimate the Helmholtz energy contributions associated with ion–solvent and ion–ion interactions. Achieving quantitative agreement requires empirical adjustments to the Born radius. Notably, the optimized Born radii are significantly larger than the actual ion sizes used in the molecular simulations, questioning the primitive model’s applicability. This work presents rigorous benchmarks for the use of MSA, DH, and Born theories, along with molecular simulation data for non-primitive model electrolytes. These benchmarks provide insights for refining existing models and advancing the development of new equations of state for electrolyte solutions.
Exploring Marine natural products as potential Quorum sensing inhibitors by targeting the PqsR in Pseudomonas aeruginosa: Virtual screening assisted structural dynamics study
Antibiotic resistance is a critical global health issue, and Pseudomonas aeruginosa is a particularly challenging pathogen. This gram-negative bacterium is notorious for its high virulence and resistance to antimicrobial agents, making it a leading cause of nosocomial infections, significantly impacting public health. The adaptability and multidrug resistance of P. aeruginosa exacerbate treatment difficulties, resulting in increased morbidity and mortality rates worldwide. Consequently, targeting bacterial quorum sensing (QS) systems is a promising strategy for the development of novel antimicrobial compounds against this resilient pathogen. In this study, a structure-based virtual screening (SBVS) approach was employed to identify marine natural products (MNPs) as potential lead molecules targeting the biofilm-forming PqsR protein of P. aeruginosa. A total of ~37,000 MNPs were initially evaluated and ranked based on docking scores using high-throughput virtual screening (HTVS), Standard Precision (SP), and Extra Precision (XP) methods. Ten lead molecules (five from the CMNPD database and five from the MNPD database) were shortlisted based on their docking scores (<−10.0 kcal/mol) and binding free energy values (MM-GBSA ΔG <−40 kcal/mol). Their drug-likeness profiles were assessed using stringent criteria in the QikProp module of Schrödinger, and their chemical reactivity was evaluated through density functional theory (DFT) calculations. The structural and energetic interactions between the identified MNPs and the PqsR-binding pocket were validated through molecular dynamics simulations (MDS) and binding free energy (BFE) calculations. Structural dynamic analyses revealed that the MNP-bound PqsR complexes demonstrated stable interactions within the binding pocket, with hydrophobic residues such as L208, I236, and I263 playing a crucial role in maintaining stability. Among the identified MNPs, CMNPD14329, CMNPD23880, MNPD13399, and MNPD13725 emerged as promising lead molecules for further research. These candidates can serve as foundations for developing structural analogs with enhanced binding affinities for PqsR and other biofilm-forming proteins. Further experimental validation is essential to confirm the therapeutic potential of these identified MNPs.
The dynamics of substituted benzoate anions undergoing counterion condensation in lamellar phase dispersions
We have studied the interaction of three ortho-substituted benzoate anions (2-ethylbenzoate, 2-chlorobenzoate, and 2-hydroxybenzoate) and three para-substituted benzoate anions (4-ethylbenzoate, 4-chlorobenzoate, and 4-hydroxybenzoate) with lamellar phase dispersions of the di-chain cationic surfactants 2,3-diheptadecyl ester ethoxypropyl-1,1,1-trimethyl-ammonium chloride (DHTAC) and dioctadecyl-dimethyl-ammonium chloride (DODMAC) using avoided level crossing muon spin resonance (ALC-μSR) spectroscopy. Highly polarized spin probes were produced in situ by the addition of muonium to the aromatic anions, and the muon and methylene proton hyperfine coupling constants (hfccs) of these radical anions were determined from the Δ1 and Δ0 resonance fields in the ALC-μSR spectra. The motionally averaged dipolar muon hfccs, |Dμ‖|, were determined from the width and amplitude of the Δ1 and Δ0 resonances and used to estimate the extent of reorientational motion. The results are consistent with the counterions being electrostatically trapped near the oil/water interface of the surfactant bilayer and undergoing large amplitude anisotropic motion. This motion is generally more restricted in DODMAC bilayers compared with DHTAC, which is likely related to the relative flexibility of the headgroups to which the counterions are loosely bound. The motion of the ortho isomers is generally more restricted than the para isomers, while there is no obvious trend regarding the ethyl, chloro, and hydroxy substituents.
Listeria monocytogenes infection in intestinal epithelial Caco-2 cells with exposure to progesterone and estradiol-17beta
Listeria monocytogenes (Lm) is a food-borne pathogen associated with serious pregnancy complications, including miscarriage, stillbirth, preterm birth, neonatal sepsis, and meningitis. Although Lm infection within the gastrointestinal tract is well studied, little is known about the influence sex hormones may have on listeriosis. Estradiol-17beta and progesterone not only have receptors within the gastrointestinal tract but are significantly increased during pregnancy. The presence of these hormones may play a role in susceptibility to listeriosis during pregnancy. Caco-2 cell monolayers were grown on trans-well inserts in the presence of estradiol 17-beta (E2), progesterone (P4), both hormones, or no hormones (control). Cells were inoculated with Lm for 1 hour, before rinsing with gentamycin and transfer to fresh media. Trans-epithelial resistance was recorded hourly, and bacterial burden of the apical media, intracellular lysates, and basal media were assessed at 6 hours post inoculation. There were no significant differences in bacterial replication when directly exposed to sex steroids, and Caco-2 cell epithelial barrier function was not impacted during culture with Lm. Addition of progesterone significantly reduced intracellular bacterial burden compared to estradiol 17-beta only and no hormone controls. Interestingly, estradiol 17-beta only treatment was associated with significantly increased Lm within the basal compartment, compared to reduction in the intracellular and apical layers. These data indicate that the sex hormones P4 and E2 alone do not significantly impact intestinal epithelial barrier integrity during listeriosis, but that addition of P4 and E2, alone or in combination, was associated with reduced epithelial cell bacterial burden and apical release of Lm.