Browse Articles

Radical Ring Expansion Catalyzed by an α-Ketoglutarate-Dependent Dioxygenase in the Biosynthesis of Tropolones

Comparative evaluation of four fully automated immunoanalyzers for the simultaneous detection of HBeAg and Anti-HBe

Background Hepatitis B envelope Antigen (HBeAg) and anti-hepatitis B envelope Antigen (anti-HBe) are crucial markers for evaluating hepatitis B virus infection status and guiding clinical decisions. Considering the increasing prevalence of HBeAg-negative variants, accurate detection of both markers is essential. This study aimed to examine the analytical performance of four fully automated immunoanalyzers for the simultaneous detection of HBeAg and Anti-HBe and to assess the inter-platform concordance. Methods In total, 439 leftover serum samples from routine clinical testing for HBeAg or anti-HBe testing were analyzed using four immunoanalyzers: Architect i2000 and Alinity i (Abbott), Cobas e801 (Roche), and Atellica IM 1600 (Siemens). Samples not tested immediately were stored at 4 °C and analyzed within 24 hours of storage. Verification of Precision followed the CLSI EP15-A3 guidelines, and methods were compared according to the CLSI EP09-A3 guidelines. Qualitative agreement was assessed using Cohen’s κ, whereas quantitative correlation was evaluated using Deming regression and R² values. Results Architect i2000 and Alinity i exhibited the highest correlation (R² = 0.9960) and concordance (κ = 0.953 for HBeAg, κ = 0.971 for anti-HBe). Cobas e801 showed strong overall correlation with Architect i2000 (R² = 0.9838), but displayed a systematic negative bias near the cutoff, substantially reducing qualitative agreement. Atellica IM 1600 demonstrated relatively weaker correlation with the other three platforms. Conclusions Inter-platform discrepancies observed may impact clinical interpretation. As these discrepancies primarily stem from systematic bias, they can be readily mitigated by adjusting the reference values. Overall, further harmonization efforts are essential to enhance inter-platform agreement and ensure consistency in clinical decision-making.

Cocaine-activated ion channels engineered to break the loop of addiction in rats

A Functional Assay for Mining Noninhibitory Enzyme Ligands from One Bead One Compound Libraries: Application to E3 Ubiquitin Ligases

SARS-CoV-2 antibody and neutralization dynamics among persons with natural- and vaccine-induced exposures

Previous SARS-CoV-2 research indicates that antibody levels and corresponding neutralization potential increase with additional exposures (comprising vaccination or infection), and that hybrid immunity resulting from combined vaccination and natural infection is more robust than either alone. However, it is unclear whether or how antibody levels increase or eventually plateau with repeated exposures and how SARS-CoV-2 exposure differs by sex or other demographic factors. Research regarding the association of antibody production with neutralization potential is also limited. We conducted this analysis within the RESPIRA population-based cohort in Costa Rica to investigate relationships between antibody levels and neutralization potential at increasing exposure levels. We examined immunological profiles from systematically defined single-exposure groups (one vaccine dose or one natural infection), double-exposure groups (two vaccine doses or one vaccine dose following a natural infection), and a triple-exposure group (two vaccine doses following a natural infection). We used a S1-RBD-based serological assay for antibody level detection and a pseudovirion assay for neutralization potential quantification. Using linear regression, we compared antibody levels and pseudoneutralization geometric mean titers between exposure groups. For single exposure groups, one vaccine dose was inferior to natural infection, but a second vaccine dose was superior to natural infection. For double exposure groups, those who were vaccinated once after infection developed higher levels of antibodies and higher neutralization potential compared with those who had only two vaccine doses. We note that peak antibody levels following an exposure may plateau after two exposures while neutralization potential continues to increase with a third exposure dose. Response patterns were comparable in males and females and in sensitivity analyses stratified by age, vaccine type, and pandemic wave. These results provide evidence that SARS-CoV-2 vaccination after COVID infection provides immunological benefit and suggest neutralization potential continues to increase after a second vaccine dose despite plateauing of antibody levels.

Artificial Protrusion Architectures Enabling Horizontal-Diffusion Nucleation for Stable Zinc-Based Batteries

Do third age adults benefit equally in well-being from activity participation? The moderating effect of financial status

The relationship between activity participation and well-being has been well documented for third age adults. However, little has been known about how the financial status influences this relationship. This study aims to investigate the moderating effect of financial status on the association of activity level with subjective happiness and quality of life among third age adults. Systematic sampling was used to select a sample of 304 adults aged 50 and older from an active ageing institute in Hong Kong. Hierarchical regression analyses indicated that activity level was a salient predictor for subjective happiness and quality of life when controlling for socio-demographics. It was not salient anymore when its interaction term with financial status was added to the model. The interaction term significantly predicted quality of life but not subjective happiness. When the data were separated by financial status, activity level saliently predicted subjective happiness and quality of life for participants with good or very good financial statuses but not for those with poor or average statuses. The results suggested that financial status played a moderating role in the relationship between activity participation and well-being. Specifically, third age adults with limited financial resources need more welfare support to benefit from activity participation.

Compression causes cancer cells to start spreading

<i>De Novo</i> Structure Determination of Covalent Organic Frameworks by NMR Crystallography

Real-time and immediate effects of backward walking exercise on pain intensity and lumbopelvic movement control in individuals with chronic non-specific low back pain with lumbar flexion syndrome

Objective Backward walking may promote the preferential recruitment of lumbar extensors to optimize flexed spinal posture adopted LBP flexion subgroup. This cross-sectional study investigated the backward-walking exercise on a) real-time muscle activation, and b) its immediate effect on back pain intensity, movement control and lumbopelvic muscle activation in individuals with chronic non-specific LBP characterized with lumbar flexion syndrome. Method Thirty adults with chronic non-specific LBP with clinical manifestation of flexion syndrome received assessments of their movement control at static standing and during the five-minute forward walking test, conducted before and after a 15-minute treadmill walking training in forward or backward direction (as the immediate effect), while real-time adaptation of the lumbopelvic muscles during walking training was also evaluated. Comparisons of back pain intensity, ratio of the normalized electromyography (EMG) of the paired lumbopelvic muscles during walking, and performance of the lumbar movement control tests (LMC) using inferential statistics to analyze between- and within-subject effects differences for the a) real-time and b) immediate effects of the single session of walking training designated in a backward direction as compared to forward direction. Results Two-way repeated measures analysis of covariance (ANCOVA) was adopted to minimize the confounding effect from covariates identified (maximal tolerable gait speed for EMG amplitude analysis, and gender for pain intensity and performance in lumbar movement control (LMC) tests). Significant post-training improvement in pain intensity (p = 0.014) and overall performance of the LMC tests (p = 0.006) were found for those who received backward walking training. Significant overall between-group effect (p = 0.022–0.026) and time-and-group interaction effect (p = 0.004–0.022) of ipsilateral internal oblique (IO) to multifidus (MF) ratio were found in swing phases of both legs. For ipsilateral erector spinae (ES) to rectus abdominis (RA) ratio, significant time effect (p = 0.022), between-group differences (p = 0.031), and real-time reduction during forward walking in left swing phase, and significant between-group differences (p = 0.024), time-and-group interaction effect (p = 0.009), and real-time increase during backward walking in right swing phase were noted. Real-time increasing trend during backward walking and real time decreasing trend of ipsilateral MF to ES ratio during forward walking were observed in stance phase of both legs, with time-and-group interaction effect at 6th (p = 0.007) and 12th minute (p = 0.006) during walking training in left stance phase. Conclusions Backward walking exercise emerges to benefit LBP patients with lumbar flexion syndrome by inducing real-time increase in back extensors and deep stabilizing muscle recruitment together with the immediate post-training improvement in pain intensity and LMC test performance. Further research with longer training duration and larger sample size are recommended to better understand if greater and more sustainable therapeutic effect can be achieved with the walking exercise in backward direction for this specified LBP subgroup.

Enantioselective Total Syntheses of Sannamycins A and B

Solving multi-scenario hybrid flow shop scheduling problem based on an improved probe machine model

The hybrid flow-shop scheduling problem is widely present and applied in industries such as production, manufacturing, transportation, and aerospace. In recent years, due to the advantages of nonlinear access and fully parallel processing, the probe machine has shown powerful computing capabilities and promising applications in solving various combinatorial optimization problems. This work firstly proposes an Improved Probe Machine with Multi-Level Probe Operations (IPMMPO) and ingeniously designs general data libraries and probe libraries tailored for multi-scenario HFS problems, including HFS with identical parallel machines and HFS with unrelated parallel machines, no-wait scenario, and standard scenario. Secondly, based on the data libraries of the IPMMPO, two tuple sets suitable for constraint programming modeling are further designed as data preprocessing. Next, a CP model (IPMMPO-CP) applicable to multi-scenario HFS problems is proposed. Finally, based on a large number of instances and real cases, IPMMPO-CP is compared with 9 representative algorithms and 2 latest CP models. The results demonstrate that the proposed IPMMPO-CP outperforms the compared algorithms and models.

'How is this possible?' — two species birthed by one mother

Financial burden of cancer in Nepal: Factors associated with annual cost and catastrophic health expenditure

Background There is a dearth of comprehensive research on the financial burden of cancer in low-resource settings. This study aims to identify factors associated with annual cost of cancer care and catastrophic health expenditure as well as estimate the impoverishment linked with cancer treatment in Nepal. Methods This cross-sectional study was conducted in two tertiary public cancer hospitals of Nepal. Face-to-face interviews were conducted with 387 patients undergoing active treatment for lung, breast, cervical, stomach, and oesophagus cancers, recruited using a purposive-consecutive sampling strategy. A generalized linear model was used to identify factors associated with annual cost, while a multivariable logistic regression model was used for catastrophic health expenditure. Pen’s Parade diagram was plotted to estimate impoverishment linked to cancer. Results The annual average cost of cancer care was 3,687 United States Dollar (479,310 Nepalese rupees). Factors significantly associated with higher annual cancer costs included secondary and above education, treatment duration of 6–12 months and above one-year, combined treatment modalities, admission to inpatient care, and prior visits to private health facilities. Cervical cancer (compared to lung cancer) was significantly associated with lower costs. The incidence of catastrophic health expenditure was 96.9% and 83.9% at the 10% and 25% threshold of annual household expenditure, respectively. Treatment duration of 6–12 months, admission to inpatient care, and lowest to higher wealth quintiles were associated with higher odds of catastrophic health expenditure compared to treatment duration of less than six months, no admission to inpatient care, and highest wealth quintiles, respectively. Similarly, 26% of the patients experienced impoverishment associated with cancer treatment expenses. Conclusion Seeking cancer treatment posed a substantial financial risk to patients in Nepal. Most of the patients experienced catastrophic health expenditure while a quarter of the patients experienced impoverishment following cancer treatment expenses, highlighting the need for strengthened social health protection mechanisms.

Enantioselective Synthesis of α-Oxygenated Ketones via Organocatalytic Formal O–H Bond Insertion of Sulfonium Ylides

Sectoral linkages and their influence on structural change: The case of China

Structural change is a fundamental aspect of a country's economic development process. Unlike traditional literature, our research integrates input-output analysis with a multisector general equilibrium model to investigate the role of sectoral input-output linkages throughout this process. By utilizing this framework and applying it to Chinese data, we find that sectoral input-output linkages are as critical as final demand in our analysis. The stability of the manufacturing sector and the prosperity of the services sector are significantly influenced by these linkages. Our findings remain robust in counterfactual analyses, even after modifying the model specifications. We apply methodologies from production networks research to elucidate the mechanisms by which linkages function. Through structural decomposition analysis, we identify the various components that constitute these driving forces. Ultimately, our results align closely with our baseline findings.

High-Density W Single Atoms in Two-Dimensional Spinel Oxide Break the Structural Integrity for Enhanced Oxygen Evolution Catalysis

Leveraging synthetic data produced from museum specimens to train adaptable species classification models

Computer vision has increasingly shown potential to improve data processing efficiency in ecological research. However, training computer vision models requires large amounts of high-quality, annotated training data. This poses a significant challenge for researchers looking to create bespoke computer vision models, as substantial human resources and biological replicates are often needed to adequately train these models. Synthetic images have been proposed as a potential solution for generating large training datasets, but models trained with synthetic images often have poor generalization to real photographs. Here we present a modular pipeline for training generalizable classification models using synthetic images. Our pipeline includes 3D asset creation with the use of 3D scanners, synthetic image generation with open-source computer graphic software, and domain adaptive classification model training. We demonstrate our pipeline by applying it to skulls of 16 mammal species in the order Carnivora. We explore several domain adaptation techniques, including maximum mean discrepancy (MMD) loss, fine-tuning, and data supplementation. Using our pipeline, we were able to improve classification accuracy on real photographs from 55.4% to a maximum of 95.1%. We also conducted qualitative analysis with t-distributed stochastic neighbor embedding (t-SNE) and gradient-weighted class activation mapping (Grad-CAM) to compare different domain adaptation techniques. Our results demonstrate the feasibility of using synthetic images for ecological computer vision and highlight the potential of museum specimens and 3D assets for scalable, generalizable model training.

Carbon-Caged-Yttria Catalysts for Stable Electrosynthesis of H₂O₂ in Concentrated Acid

Complications in cesarean sections: A national survey of obstetric protocols and outcomes in Spain

Introduction Cesarean sections are among the most common obstetric surgeries worldwide. While generally safe, they can be complicated by numerous factors increasing risks for both mother and fetus, and posing significant challenges in clinical practice. In Spain, the absence of unified protocols for managing high-risk cases underscores the need for systematic guidance to improve maternal outcomes and reduce morbidity. Materials and methods A 45-question survey evaluated the management of complicated cesarean sections in Spain among members of the Perinatal Medicine Section of the Spanish Society of Gynecology and Obstetrics. The survey was developed and internally validated by the Spanish Society of Gynecology and Obstetrics. It was distributed online to all registered members. A total of 744 responses were collected between March and June 2024. Inclusion criteria were current obstetric practice and at least one year of experience. Results Data from 744 Spanish gynecologists was gathered. Respondents, had a median of 15.0 (P25-P75 = 17.0–24.0) years of experience, reported performing an average of 43.4 (SD = 62.1) cesarean sections per month, with 21.9% classified as complicated. Hospital level influenced case volume and complexity, with higher-level hospitals reporting higher incidence of complicated cesarean sections. Only 14.5% of institutions had established preoperative protocols for complicated cesarean sections, showing improved outcomes when implemented. Key complications included blood loss (1000–1500 ml in 35.3% of cases), fetal extraction difficulties, uterine atony, and adjacent organ trauma. Postoperative issues such as infections and wound dehiscence were also common. Conclusion This study highlights the need for standardized protocols in Spain to manage complicated cesarean sections. Their implementation could reduce intraoperative blood loss, decrease maternal morbidity from hemorrhage and trauma, and improve postoperative recovery and hospital stay duration.