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Exploring lithium-ion diffusion and electronic properties in defective graphite via molecular dynamics and density functional theory
The thermodynamic, kinetic, and mechanical properties of graphite anodes significantly influence the performance of lithium-ion batteries. Molecular dynamics simulations and density functional theory calculations were employed to examine the effects of defects in graphite on these properties. In particular, the influence of three types of defects—Stone–Wales (SW), single vacancy (SV), and double vacancy (DV)—at defect densities below 0.4% was analyzed, including their impact on graphite density, charge transfer, voltage, lithium-ion diffusion, and mechanical stability. The results show that defects in graphite form bridge, ylide, and spiro configurations, with structural stability decreasing in the order of SV > SW > DV. As defect density increases, the lithium-ion diffusion coefficient decreases significantly from 4.71 × 10−8 to 3.75 × 10−11 Å2/ps as lithium concentration increases from Li0.02C6 to LiC6. In contrast, for Li0.02C6, the diffusion coefficient rises with increasing defect density, from 2.94 × 10−9 to 1.29 × 10−9 Å2/ps. Mechanical analysis reveals that increasing defect density reduces Young’s modulus from 936.49 to 743.54 GPa and ultimate tensile strength from 94.59 to 58.50 GPa, highlighting the detrimental effect of defects on graphite's mechanical stability. Defects introduce localized electronic states within the bandgap, promoting lithium-ion diffusion at higher concentrations and disrupting the graphite structure to create new diffusion paths. These findings underscore the critical role of defect engineering in optimizing graphite anode performance and provide insights for the design of high-performance anode materials.
PTPRC is an immunotherapeutic predictor and serum biomarker in lung adenocarcinoma correlated with immune cell infiltration
Factors associated with stroke recurrence and mortality in ischemic and haemorrhagic stroke: Protocol for a systematic review and meta-analysis
Background and objectives Stroke is one of the leading causes of death and disability worldwide. People with stroke face a significant risk of recurrence, however, there is a lack of consensus on the risk factors for stroke recurrence. Previous systematic reviews in this area are either outdated, focus exclusively on clinical risk factors, or are limited by geographical region, stroke subtype or age group. This review aims to systematically identify clinical and lifestyle risk factors associated with stroke recurrence and mortality in people with stroke. Methods A systematic search will be conducted in four electronic databases (PubMed, EMBASE, CINAHL and PsycINFO) and grey literature sources. Only prospective cohort studies that estimate the association between risk factors and stroke recurrence and/or mortality in adults with ischemic and haemorrhagic stroke will be included. The exposures of interest are clinical and lifestyle risk factors, including vascular and cardiac factors such as hypertension or atrial fibrillation, and behavioural factors such as physical activity, nutrition, or smoking. Two independent reviewers will conduct screening, data extraction, and risk of bias assessment using the ROBINS-E tool, while the GRADE approach will be used to evaluate the certainty of evidence. A meta-analysis using a random-effects model will be used to determine the overall effect for each exposure on stroke recurrence and/or mortality. However, if a meta-analysis is not justified, a narrative synthesis will instead be conducted. Discussion Recurrent strokes are associated with greater mortality and poorer functional prognosis than first-time events, imposing greater economic burden on healthcare services. This review will identify factors that increase one’s risk for recurrence, thereby informing the development and refinement of clinical guidance for secondary stroke prevention; a key priority for both those living with stroke and the wider health service.
Stern–Gerlach deflection of cryogenically cold polyatomic molecules in superfluid nanodroplets
Beam deflection is capable of providing valuable information about the magnetic moments of molecules and clusters and about the relaxation dynamics of their spins. However, observations have been hampered by magnetic couplings to excited vibrational and rotational states of polyatomic systems, which are challenging to control, characterize, and systematize. In this work, we carried out deflection measurements on superfluid helium nanodroplets doped with high-spin FeCl2 and CoCl2 molecules and their complexes. This enabled quantitative determination of the magnetic moments of molecules and clusters at extremely low, and fully defined, temperature of all of their degrees of freedom. The spin magnetic moments become thermalized and oriented along the applied field. Dimers and trimers are found to be antiferromagnetically ordered. The issue of rates and mechanisms of molecular spin relaxation within the cryogenic helium matrix is highlighted.
Quasiparticle interaction originating from Bogoliubov Fermi surfaces under pressure in 18%-S substituted FeSe studied via NMR
Abstract S-substituted FeSe superconductors in the tetragonal phase display several unique features among iron-based superconductors, particularly the presence of zero-energy excitations in the superconducting (SC) state. The recent concept of Bogoliubov Fermi surfaces (BFSs)—a theoretical model describing ultranodal states—has attracted considerable interest. Nuclear magnetic resonance (NMR) studies on FeSe1 − x S x (x = 0.18) have revealed an anomalous low-energy spin fluctuations deep in the SC state. The low-energy spin fluctuations are enhanced with decreasing temperature, supporting strong Bogoliubov quasiparticle interactions associated with BFSs. Here, we further investigate these correlation effects through 77Se-NMR measurements of FeSe1 − x S x (x = 0.18) under pressures up to 2.0 GPa and temperatures down to ~ 100 mK. The results demonstrate that the anomalous enhancement is suppressed but persists under pressure, implying that quasiparticle interactions become weak by applying pressure. Furthermore, spin fluctuations in the normal state exhibit different temperature dependence from those deep in the SC state, suggesting that the nesting properties of normal electrons differ from those of Bogoliubov quasiparticles. These findings are consistent with the theoretical model of BFSs with C 2 symmetry and strengthen evidence for Bogoliubov quasiparticle interactions, providing insights into the unconventional pairing state of this system.
Association between Endothelial Activation and Stress Index and mortality in diabetic nephropathy ICU patients: A retrospective cohort study
Background Diabetic nephropathy (DN) is a serious complication of diabetes mellitus, often leading to poor outcomes in critically ill patients. Endothelial Activation and Stress Index (EASIX), a marker of endothelial dysfunction and systemic stress, has been associated with adverse outcomes in various diseases, but its role in predicting mortality in DN patients remains unclear. Methods A retrospective cohort study was conducted using the MIMIC-IV database. A total of 1,260 critically ill DN patients were included and stratified into tertiles based on their EASIX scores. Kaplan-Meier survival analysis, Cox proportional hazard models, and restricted cubic spline regression were applied to evaluate the association between EASIX and 30- and 60-day all-cause mortality. Subgroup analyses were also performed to assess interactions with key patient characteristics. Results Patients with higher EASIX scores had significantly increased ICU and in-hospital mortality rates. Cox regression analyses revealed that EASIX was an independent predictor of mortality after adjusting for age, sex, and comorbidities (HR: 1.14; 95% CI: 1.03–1.26; p = 0.01). Kaplan-Meier analysis showed significantly worse survival rates in the highest EASIX tertile. Subgroup analysis showed that higher EASIX scores were still associated with short-term survival in patients with DN in the presence of older age, male gender, and severe complications. Conclusion Higher EASIX scores are associated with increased short-term mortality in critically ill DN patients, highlighting its value as a prognostic biomarker for risk stratification and personalized management. Further studies are needed to validate these findings and explore therapeutic interventions targeting endothelial dysfunction.
Brazilian PhD students opt out of US research opportunities
The mechanics of nucleation and growth and the surface tensions of active matter
Homogeneous nucleation, a textbook transition path for phase transitions, is typically understood on thermodynamic grounds through the prism of classical nucleation theory. However, recent studies have suggested the applicability of classical nucleation theory to systems far from equilibrium. In this article, we formulate a purely mechanical perspective of homogeneous nucleation and growth, elucidating the criteria for the properties of a critical nucleus without appealing to equilibrium notions. Applying this theory to active fluids undergoing motility-induced phase separation, we find that nucleation proceeds in a qualitatively similar fashion to equilibrium systems, with concepts such as the Gibbs–Thomson effect and nucleation barriers remaining valid. We further demonstrate that the recovery of such concepts allows us to extend classical theories of nucleation rates and coarsening dynamics to active systems upon using the mechanically derived definitions of the nucleation barrier and surface tensions. Three distinct surface tensions—the mechanical, capillary, and Ostwald tensions—play a central role in our theory. While these three surface tensions are identical in equilibrium, our work highlights the distinctive role of each tension in the stability of active interfaces and the nucleation and growth of motility-induced phases.
Radiomics-based machine-learning method to predict extrahepatic metastasis in hepatocellular carcinoma after hepatectomy: a multicenter study
HPLC-MS profiling and protective potential of the defatted aqueous methanol extract of two Syzygium species against cadmium chloride-induced nephrotoxicity in rats
Cadmium (Cd), a highly toxic heavy metal, is used in food and agricultural products while displaying nephrotoxicity to animals and humans. The genus Syzygium (Myrtle family) is rich in precious phenolic metabolites with various therapeutic values. This study investigated the phenolic content and the therapeutic potential of the defatted 80% aqueous methanol extract (DE) of S. malaccense and S. samarangense leaves against Cd-induced kidney injury in rats for the first time. High-performance liquid chromatography-Mass spectrometry (HPLC-MS), in addition to Folin-Ciocalteu and aluminium chloride colourimetric methods, depicted the phenolic metabolites, total phenolic content, and total flavonoid content, respectively. The nephroprotective effect was investigated using fifty-six female Sprague Dawley rats divided into eight groups: control group, CdCl2-treated group (3 mg/kg/i.p/7 days), and three groups of each species treated with the DE (250, 500, and 1000 mg/kg/o.p., respectively). The phytochemical analysis revealed the richness of S. samarangense DE by phenolic and flavonoid content over S. malaccense. The HPLC-MS showed the tentative identification of sixty-two compounds, in positive and negative ionization modes, belonging to phenolic acids (1−6), flavonoids (7−52), and miscellaneous compounds (53−62). Both extracts were considered safe up to 5 g/kg. At the maximum tested dose (100 mg/Kg), the DEs significantly (p < 0.001) boosted the levels of antioxidant markers by 3.3–6 fold, lessened the inflammatory indicators by 66.8%−75.1%, and reduced the apoptotic parameters by 45.4–73.3%, compared to the CdCl2-treated group. Additionally, the DEs maintained the mitochondrial function and inhibited autophagy via decreasing adenosine monophosphate-activated protein kinase by 49.2%−50.6%, and baclin-1 by 49.5%−56.1%. Additionally, the DEs increased the mammalian target of rapamycin (mTOR) by 4.7–4.9 fold. Additionally, the DE ameliorated CdCl2-induced elevations in serum ALT and AST, indicating a protective effect against systemic toxicity. Ultimately, the DE of S. malaccense and S. samarangense protect against Cd-induced nephrotoxicity that may be correlated to their abundant phenolic content. However, selecting suitable formulations and implementing clinical studies are among the future directions.
Daily briefing: These rappelling robots autonomously explore underground tunnels
Robust estimation of rotational diffusion tensors of proteins from molecular dynamics simulations
Rotational diffusion is a fundamental physical process that determines the rotational motion of proteins in solution. It plays a role, for example, in molecular association processes and in theories of spectroscopic experiments in solution. In addition to experimental methods, molecular dynamics (MD) simulations have emerged as a powerful method to investigate rotational diffusion. Diffusion models are fitted to rotational correlation functions extracted from the simulations. In this work, we conducted a time-dependent analysis of the model parameters prior to fitting, using extended all-atom MD simulations of ubiquitin as a model system. A comparison to Brownian dynamics (BD) simulations confirms whether the rotational dynamics observed in MD actually follow the theory of Brownian rigid-body diffusion. In addition, the analysis reveals correlation time intervals that are suitable for fitting anisotropic, semi-isotropic, or isotropic diffusion models. To this end, a two-step optimization scheme is employed that combines a global and a local search in parameter space. BD simulations are used to estimate uncertainties of the diffusion coefficients and directional uncertainties of the principal axes. We found that ubiquitin exhibits nearly semi-isotropic rotational dynamics, in good agreement with the experimental NMR data. The approach is general and can be used to investigate, for example, the rotational diffusion of molecules in various biomolecular environments or to compute NMR relaxation parameters of proteins. An implementation of the method is freely available at https://github.com/MolSimGroup/rotationaldiffusion.
Exposure to online hate speech is positively associated with post-traumatic stress disorder symptom severity
Kummerowia striata extract protects paracetamol-induced liver injury by modulating the S1P/Nrf2/Keap1 pathway
Background Drug-induced liver injury remains a significant challenge in both drug development and clinical applications. Acetaminophen (APAP), a commonly used analgesic and antipyretic, can cause liver damage when overdosed, with APAP-induced liver injury being one of the leading causes of acute liver injury. Kummerowia striata (Ks), a leguminous plant, has been reported to contain chemical compounds with anti-inflammatory and antioxidant activities. However, its potential therapeutic effects in liver diseases remain inadequately explored. Objective This study aims to investigate the protective effect of Kummerowia striata extract against APAP-induced acute liver injury and further explore its potential molecular mechanisms. Methods C57BL/6J mice were pre-treated with Ks extract by gavage for 3 days. On the second day, treatment was discontinued, and the mice were fasted for 16 hours. After the fasting period, the final dose of Ks extract was administered, followed by an intraperitoneal injection of APAP (300 mg/kg) 1 hour later to establish a drug-induced liver injury model. Tissue samples were collected 24 hours after modeling. To investigate the molecular mechanisms by which Ks extract prevents APAP-induced acute liver injury, network pharmacology, the GEO database, and molecular docking analysis were employed. Results Ks extract exhibited a significant gender-independent protective effect in preventing APAP-induced acute liver injury in mice. In male mice, Ks extract attenuated the occurrence of acute liver injury by modulating the sphingosine-1-phosphate/ Sphingosine-1-Phosphate Receptor 2/ Sphingosine-1-Phosphate Receptor 4(S1P/S1PR2/S1PR4) signaling pathway and the upstream regulator SPHK1. This, in turn, regulated the binding of Kelch Like ECH Associated Protein 1 (Keap1) to Nuclear factor erythroid 2-related factor 2(Nrf2), alleviating oxidative stress and inflammatory responses. Discussion This study illustrates that Ks exerts a protective effect against APAP-induced acute liver injury by modulating oxidative stress and inflammatory responses through multiple mechanisms. Notably, Ks inhibited Keap1 expression and restored Nrf2 signaling, indicating a potential regulatory role in mitigating mitochondrial oxidative damage and ferroptosis. Furthermore, Ks downregulated SPHK1 expression and reduced levels of the bioactive sphingolipid S1P, as well as its receptors S1PR2 and S1PR4, unveiling a previously unreported involvement of the SPHK1/S1P/S1PR2/4 axis in liver injury. Interestingly, sex-based differences in APAP hepatotoxicity were observed, with female mice exhibiting lower susceptibility, yet still responding to Ks treatment. These findings not only validate the hepatoprotective potential of Ks but also provide new mechanistic insights involving the Nrf2/Keap1 and S1P/S1PR2/S1PR4 signaling pathways, thereby laying a foundation for its development as a candidate therapeutic agent for acute liver injury.
Optimization of microwave absorption properties based on the construction of Ni–TiN heterojunctions
In this study, Ni–TiN@CN nanocapsules were successfully prepared by the DC arc method and the self-polymerization reaction of dopamine. The effect of material composition on their microwave absorbing properties was systematically investigated. The crystal structure, core–shell morphology, and the successful construction of the nitrogen-doped carbon layer of samples were confirmed by x-ray diffractometer, Raman spectroscopy, x-ray photoelectron spectroscopy, transmission electron microscopy, and scanning electron microscopy. The synergistic effect of the dielectric and magnetic losses is optimized by the introduction of Ni elements. Electromagnetic parameter tests show that the dielectric relaxation loss of the material is further significantly enhanced by the multi-interface heterostructure constructed after coating the nitrogen-doped carbon shell layer. Ni–TiN@CN nanocapsules have a reflection loss of −47.74 dB at a thickness of 2.6 mm and a combined effective absorption bandwidth (RL &lt; −20 dB) of 4.5 GHz. It exhibits excellent microwave absorption performance. This study provides a new idea for the design of highly efficient microwave absorbing materials. It confirms that the construction of multi-interface heterostructures can effectively regulate the microwave absorbing properties of materials.
Synthesis and characterization of hematite nanomaterials imprinted with acetone, ethanol and methanol for AI-Based IoT gas sensor arrays
Weight loss journeys: Exploring social influences and determinants of health in an exploratory rural German intervention
Overweight and obesity are highly prevalent across Western populations and contribute substantially to the global burden of non-communicable diseases such as cardiovascular disease and diabetes. Despite numerous intervention efforts, achieving and sustaining long-term weight loss remains a challenge. Social Determinants of Health (SDoH) play a critical role in shaping health outcomes – including weight and weight loss trajectories – and vary across social groups and geographic contexts. This qualitative study explores participants’ perceptions of personal and contextual SDoH influencing their weight loss journeys within a rural German population enrolled in a general practitioner-led pilot intervention. Semi-structured interviews were conducted with 16 participants from the HAPpEN trial (General Practitioner-led Obesity Prevention Program: Exercise and Nutrition), which focused on individuals living in a rural area of Upper Franconia. Interview data were analyzed using a grounded theory-informed approach to qualitative content analysis, guided by the SDoH framework as a sensitizing concept. Coding and theme development followed an iterative process involving constant comparison and discussion within the research team. Key determinants affecting weight loss efforts included individual routines and schedules, social and household networks, mental health, and work-related demands. Broader contextual factors such as socialization, cultural norms, and the availability of health-supporting infrastructure also emerged. The dynamic interplay between personal motivation and structural or environmental influences appeared to be central to weight management success. This study is limited by its small and relatively homogeneous sample – predominantly female and drawn from a single rural region – which may restrict transferability to more diverse populations or urban settings. Nonetheless, the findings offer practical implications for tailoring weight loss interventions to rural contexts by incorporating the complexity of individual and social determinants.
Forces between charge regulated surfaces inside an electrolyte solution
We study the interaction between two charge-regulated surfaces immersed in a 1:1 electrolyte solution, analyzing how this interaction varies with the ionic strength and pH of the solution. This system can be thought to represent two like-charged colloidal particles with radii much larger than the Debye length. Our theoretical approach is based on a recently developed theory that modifies the traditional Poisson–Boltzmann equation to account for the discrete nature of surface groups. We demonstrate that charge regulation has a significant impact on the interaction forces between the surfaces compared to systems with fixed surface charges. Notably, unlike unregulated surfaces, increasing the salt concentration can lead to a stronger repulsive force between the surfaces.
Global map of characterized dust sources using multisource remote sensing data
Abstract The most recent high-resolution global map of dust emission sources is provided by Ginoux et al. (2012), which utilizes an aerosol loading approach based on time series of MODIS Aerosol Optical Depth (AOD). However, advancements in remote sensing technology and analytical techniques have created a growing need for more accurate and up-to-date maps of global dust sources to enhance the understanding and management of this phenomenon. In this study, we first calculated the global mean Sentinel-5P Absorbing Aerosol Index (AAI) for the period 2018–2024. Regions with AAI values greater than 0.25 were identified as potential dust sources through histogram analysis validated by ground truth data. Next, areas without dust emission potential were excluded from the mean AAI map using a multi-stage masking process that considers land surface characteristics such as soil depth, permanent water bodies, and built-up areas. Validation results demonstrate strong performance, with a Precision of 84.7%, Recall of 80.7%, and F1-score of 82.6%, confirming the reliability of the global dust source map produced. The findings indicate that about 5% of the world’s land area acts as a dust emission source, mainly located in North Africa (67%) and Asia (30%). Land use/land cover analysis reveals that global dust sources comprise deserts, vegetative, and hydrological categories, accounting for 65%, 26%, and 9%, respectively. Among these, sandy areas, rangelands, and intermittent water bodies exhibit the largest extent on a global scale, respectively. Natural and human factors contribute 65% and 35%, respectively, to the formation of global dust sources. The frequency of dust events from desert sources has experienced an increasing trend worldwide, but in the case of non-desert sources, it has decreased in some regions, such as the Middle East. This study focused on identifying major dust emission sources based on relatively high aerosol loads over time. Our results provide a new global dust atlas that can serve as a practical foundation for climate modeling and for formulating disaster risk reduction and management plans.