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关键词： Fructooligosaccharides   1-Kestose   certified reference material   Nuclear magnetic resonance   Charged aerosol detector  

摘要： The widespread use of fructooligosaccharides (FOS) as prebiotics has increased the need for accurate quantification methods to ensure food quality. Since certified reference materials (CRMs) are essential for establishing metrological traceability for FOS analysis, a purity CRM for 1-kestose—the main component of FOS—was developed. Due to its complex structural features, such as regioisomeric glycosidic linkages and anomeric configurations, 1-kestose was characterized using two-dimensional nuclear magnetic resonance spectroscopy (NMR). Purity was determined using quantitative NMR (qNMR) and mass balance (MB) methods, yielding a certified value of 991 mg/g±3 mg/g (k = 2) with metrological traceability to the International System of Units for mass (kg) and amount of substance (mol). MB analysis revealed 9.3 mg/g of structurally related impurities, and liquid chromatography coupled with a charged aerosol detector (HPLC-CAD) identified sucrose (2.7 mg/g) and nystose (5.4 mg/g) as the dominant impurities. Furthermore, a novel analytical strategy was developed to quantify structurally related impurities using the calibration curve of the principal component (1-kestose) obtained by HPLC-CAD. Compared with the traditional external standard method, this approach exhibited a bias of less than 0.3 mg/g, highlighting its potential for determining the purity of other oligosaccharides in the FOS family and related compounds.

关键词： Transcatheter aortic valve replacement   Bicuspid aortic valve   Sievers type 1   Women   VARC-3   AS   Aortic stenosis   BAV   Bicuspid aortic valve   BE   Balloon-expandable   CAD   Coronary artery disease   CI   Confidence intervals   COPD   Chronic obstructive pulmonary disease   DOCE   Device oriented composite endpoint   HF   Heart failure   HR   Hazard ratio   LVEF   Left ventricular ejection fraction   LVOT   Left ventricular outflow tract   MAEs   Major adverse events   MSCT   Multi-slice computed tomography   NYHA   New York heart association   OR   Odds ratio   PPM   Prosthesis-patient mismatch   RCT   Randomized controlled trial   SE   Self-expanding   STS-M   Society of Thoracic Surgeons mortality   TAVR   Transcatheter aortic valve replacement   THV   Transcatheter heart valve   VARC-3   Valve academic research Consortium-3   VRR   Virtual raphe ring  

摘要： There is paucity of data regarding sex-related differences among patients with bicuspid aortic valve (BAV) undergoing transcatheter aortic valve replacement (TAVR).

关键词： CAD/CAM   dental materials   fracture resistance   polymer-infiltrated ceramic network   post-crown   Yttrium tetragonal zirconia polycrystal  

摘要： Objectives: Recently, CAD/CAM materials have become popular in dental clinics;however, information about their fracture resistance as post-crowns remains limited. This study compared the initial fracture resistance of potential single-piece post-crown materials made with CAD/CAM milling to sound teeth. Materials and Methods: Fifty freshly extracted, non-carious human central incisor teeth underwent endodontic treatment. The roots were then randomly divided into five groups based on the post systems: the control group included teeth filled only with gutta-percha. Monoblock post-crowns were made using four different systems for the other groups: LDS (IPS *** CAD (R), lithium disilicate glass-ceramic), YTZP (inCoris ZI (R), Yttrium tetragonal zirconia polycrystal), RNC (Lava Ultimate (R), resin-based nanoceramic), and PICN (VITA Enamic (R), polymer-infiltrated ceramic network). The post-crowns were cemented with resin cement and tested with a universal testing machine at a crosshead speed of 1.0 mm/min. Data analysis used one-way ANOVA and multiple comparison post-hoc Tukey tests (alpha = 0.05). Results: Significant differences were found between the groups (p < 0.001). The control group exhibited the highest fracture resistance (749.25 +/- 225.02 N). YTZP showed similar resistance to the control (p = 0.99) and LDS (447.28 +/- 168.72 N, p = 0.081), but was significantly higher than RNC (343.79 +/- 157.08 N, p = 0.0051) and PICN (348.78 +/- 157.44 N, p = 0.0059). LDS, RNC, and PICN did not differ significantly. YTZP experienced more non-repairable fractures (5/10), while PICN predominantly failed in a repairable manner (9/10). Conclusions: All CAD/CAM post-crowns exceeded functional loads for the anterior region. YTZP and LDS demonstrated greater strength, whereas PICN and RNC, despite being weaker, favored repairable failures-highlighting the importance of balancing strength and clinical manageability.

关键词： percutaneous coronary intervention   Native Americans   cardiovascular disparities   healthcare equity   acute coronary syndromes   ACS   acute coronary syndromes   CABG   coronary artery bypass grafting   CAD   coronary artery disease   CHD   coronary heart disease   CVD   cardiovascular disease   NSTEMI   non-ST-segment elevation myocardial infarction   PCI   percutaneous coronary intervention   STEMI   ST-segment elevation myocardial infarction  

摘要： Native Americans face significant disparities in cardiovascular health, including access to and outcomes of percutaneous coronary intervention (PCI). Native Americans exhibit comparable in-hospital mortality rates to Whites for acute coronary syndromes (ACS) but face delayed presentations and lower rates of timely interventions such as angiography and revascularization. Geographic isolation, limited PCI-capable facilities, and underfunded healthcare systems significantly contribute to these disparities. Furthermore, comorbid conditions such as diabetes, hypertension, and obesity are disproportionately prevalent, compounding adverse outcomes. There is a need to evaluate PCI outcomes and identify disparities in access and care among Native Americans while highlighting the need for targeted interventions. This review synthesizes data on PCI utilization and outcomes in Native American populations, focusing on unique risk profiles, systemic barriers, and comparative analyses with other racial and ethnic groups. In conclusion, evidence-based recommendations are proposed to address healthcare inequities while promoting PCI to reduce heart attacks in Native American populations.

关键词： Active control   Cam-roller mechanism   Magnetic spring   Vibration isolation   Zero stiffness  

摘要： This paper develops a novel active–passive hybrid vibration isolator that realizes absolute-zero-stiffness (AZS) behavior by integrating a tri-stable magnetic spring with a cam-roller mechanism. The tri-stable configuration introduces five equilibrium points, generating a wave-like nonlinear restoring force that is precisely counteracted by a cam-profiled compensation force to achieve AZS. This approach effectively decouples external excitations, enabling full-frequency vibration isolation with enhanced stability and low sensitivity to amplitude variations. To improve robustness against parameter uncertainties and manufacturing errors, a proportional–integral–derivative (PID) feedback loop is incorporated, forming a hybrid control strategy. Theoretical modeling, validated by finite element analysis and static testing, confirms the accuracy of the magnetic force predictions. Dynamic analysis and experimental results confirm that the proposed isolator delivers significantly enhanced isolation performance compared to conventional mono-, bi-, and tri-stable configurations. Under sinusoidal excitation over the tested ultra-low frequency range of 0.1–8 Hz, the proposed isolation method achieves vibration isolation across the entire spectrum, effectively lowering the displacement transmissibility from 16.5 dB and 19 dB in the passive tri-stable mode to –28.7 dB and –39.1 dB, respectively. Notably, the mean power consumption of the proposed control strategy remains below 1.21 W, significantly lower than that of traditional active or hybrid control approaches. Compared to state-of-the-art designs, the isolator offers superior isolation bandwidth, working stroke (10 mm), and normalized load capacity (39.52 N/cm³). Its compact form factor and low power requirement make it highly suitable for precision vibration isolation in automotive, aerospace, and mobile platforms.

关键词： Semantic segmentation   Weakly supervised   Image segmentation   CAM   Deep learning  

摘要： The core challenge in image-level weakly supervised semantic segmentation lies in generating high-quality object localization maps from simple image labels. Class Activation Map (CAM) produced by existing methods commonly suffer from two major flaws: incomplete coverage of target regions and severe background interference. To address these issues, we present a CAM-native perception-optimization framework for weakly supervised semantic segmentation. First, design a CAM generation mechanism guided by image-level weak supervision, which refines activated regions via discriminative region enhancement and spatial noise suppression. This process promotes fine-grained pixel clustering and improves the completeness of object localization. Second, introduce a spatial cue generator to enhance the adaptability of class representations, coupled with an inter-class relation propagation module that explicitly models inter-class relationships to suppress erroneous activations and significantly reduce spatial noise. Additionally, incorporate a dynamic contrastive matching strategy to eliminate background activations closely associated with the target object, ultimately producing class activation maps that are both complete and compact. Extensive experiments on PASCAL VOC 2012 and MS COCO 2014 show that our method substantially outperforms existing weakly supervised approaches, validating the effectiveness of class-aware guidance and inter-class relational modeling in improving segmentation accuracy.

摘要： Diabetic foot ulcers (DFU) are a highly dangerous and even fatal sequela of diabetes mellitus, very often becoming a lower limb amputation and imposing significant morbidity and mortality all over the world. Deep learning and machine learning have recently made breakthroughs, creating potential for being applied in medical image analysis towards the detection of DFU, but the field still faces the challenge of optimizing the performance of the models in both terms of accuracy and interpretability. The present paper solves this issue by introducing a more optimized deep learning model to detect DFUs that has been proposed by integrating a proprietary Convolutional Neural Network (CNN) structure and a Genetic Algorithm (GA) based on ensembles. Seven different optimizers were distinctly trained by the custom CNN. The genetic algorithm (GA) was then applied to pool a final ensemble model out of individual models with the most remarkable performance. This GA based ensemble had an accuracy of 97%, a precision of 95%, a recall of 99%, and an F1 score of 97%, which showed better and stronger performance than the individual single models that made up it. In addition, the study implemented Grad-CAM (Gradient-weighted Class Activation Mapping) to increase interpretation and transparency. The results obtained demonstrated that Grad-CAM was able to accurately describe the features associated with ulcers and, therefore, offers invaluable information on how the model makes its decisions to healthcare professionals.

关键词： Pseudomonas   Whole-genome sequencing   Virulence factors   Comparative analysis   Antimicrobial resistance genes   Secondary metabolites  

摘要： Bacteria of the genus Pseudomonas are Gram-negative and comprise of at least 107 diverse species. Certain members of the genus Pseudomonas emerged as major opportunistic human pathogens, and others have been used as biocontrol agents. Tsetse flies, the biological vectors of African trypanosomes, harbour diverse communities of microorganisms. Tsetse microbiota is of interest because of their possible effect on vector competence. The aim of this study was to explore genetic features of a novel Pseudomonas species strain CAM1A isolated from tsetse caught in Dodeo, Cameroon. The bacterium was isolated from tsetse fly, and the whole genome was sequenced on the Illumina Miseq platform. Sequences were assembled with SPAdes and annotated using RAST and PATRIC annotation pipelines. The draft genome, made of 61 contigs was found to be at least 5,848,000 bp long, with 5,339 coding sequences, a DNA G + C content of 64.3%, and at least 80 tRNA + rRNA genes. No plasmid was found. Taxonomic analysis based on whole-genome sequences (ANI and GGDC) and MLSA indicated that CAM1A represents a putative novel species closely related to Pseudomonas soli. Several antimicrobial resistance and efflux-mediated resistance genes were predicted, suggesting its ability to evade many antimicrobial therapies. Determination of secondary metabolites within the genome revealed seven different secondary metabolites distributed on 11 biosynthetic gene clusters. Various virulence factors were found, but the isolate was predicted to be a non-human pathogen.

关键词： Ph+ ALL   P2RX1   CaMKII   apoptosis   PI3K/Akt  

摘要： Introduction: Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL) continues to pose a major clinical challenge. Although tyrosine kinase inhibitor (TKIs)-based regimens form the cornerstone of therapy, treatment outcomes are compromised by difficulties in achieving remission, high relapse rates, and the critical issue of drug resistance. This study aims to elucidate the role of the purinergic receptor P2RX1 in the pathogenesis of and therapeutic response in Ph+ ALL. Methods: By analyzing P2RX1 expression levels in an online patient database and its association with prognosis, we evaluated the potential significance of this receptor in clinical outcomes. A P2RX1 overexpression model was established in the SUP-B15 Ph+ ALL cell line, and a series of functional experiments were conducted to assess its impact on tyrosine kinase inhibitor-induced apoptosis and proliferation capacity. To further elucidate its mechanism of action, we monitored changes in intracellular calcium ion concentration, mitochondrial membrane potential, and ATP production levels. Additionally, RT-PCR and Western blot analysis were employed to assess the activation status of the PI3K/Akt signaling pathway, CaMKII, and apoptosis-related proteins BAX, BAD, cytochrome C, and caspases Results: Analysis of the online patient database revealed that high expression of P2RX1 was significantly associated with poor clinical outcomes. Functional experiments demonstrated that overexpression of P2RX1 in SUP-B15 cells markedly enhanced their sensitivity to apoptosis induced by tyrosine kinase inhibitors;conversely, treatment with the CaMKII inhibitor KN-62 significantly suppressed cell proliferation. Mechanistically, excessive P2RX1 activation disrupts intracellular calcium homeostasis, leading to reduced mitochondrial membrane potential and ATP depletion, thereby activating the intrinsic apoptotic pathway. This process involves inhibition of the PI3K/Akt signaling pathway, hyperactivation of C

关键词： Bipolar disorder   mania   depression   extracellular vesicles   microRNA   epigenetics   biomarker  

摘要： ObjectiveThis preliminary study aimed to identify microRNA (miRNA) signatures associated with bipolar disorder (BD) by profiling blood-derived extracellular vesicles (EVs) of both putative neuronal origin and from all *** two parallel studies of individuals with BD and controls (CON), we characterized miRNA expression profiles of blood EVs selected for L1CAM, a putative marker of neuronal origin (n = 20 BD/20 CON), as well as bulk EVs (n = 21 BD/20 CON). For each study, analyses identified miRNAs differentially expressed between groups, followed by functional interrogation and testing for associations with clinical *** of Study 1 showed 34 miRNAs differentially expressed between groups and implicated PTEN, a gene whose protein levels were previously found to be altered in postmortem brain studies of BD. Results of Study 2 showed 10 miRNAs differentially expressed between groups. Limited overlap was identified between studies, with only hsa-miR-1-3p identified with the same direction of change across both types of EVs. Differentially expressed miRNAs were significantly associated with clinical features of BD only in Study *** results, albeit preliminary, reiterate a crucial role for miRNAs in the pathophysiology of BD and suggest that miRNA signatures of putative neuronal origin may more closely correspond to clinical features.