This paper describes the CMU OAQA system evaluated in the BioASQ 3B Question Answering track. We first present a three-layered architecture, and then describe the components integrated for exact answer generation and retrieval. Using over 400 factoid and list questions from past BioASQ 1B and 2B tasks as background knowledge, we focus on how to learn to answer questions using a gold standard dataset of question-answer pairs, using supervised models for answer type prediction and candidate answer scoring. On the three test sets where the system was evaluated (3, 4, and 5), the official evaluation results have shown that the system achieves an MRR of .1615, .5155, .2727 for factoid questions, and an F-measure of .0969, .3168, .1875 for list questions, respectively; five of these scores were the highest reported among all participating systems.
= 2). Extensive evaluation using nine kits demonstrated 100% concordance for both positive and negative samples. The materials exhibited excellent repeatability (coefficient of variation, CV <5%) and consistent detectability (≥95% positivity rate) at the claimed limit of detection across all kits. In summary, this study developed a well-characterized reference material system to support the standardization, development, and quality control of CHIKV nucleic acid assays. The availability of this reference material system addresses a longstanding limitation of results across different platforms and geographical regions. Their implementation is expected to facilitate assay optimization and improve the consistency of surveillance data, thereby strengthening preparedness and the accurate identification of cases, especially in non-endemic areas at risk of importation.IMPORTANCEThe absence of a World Health Organization (WHO) international standard for Chikungunya virus (CHIKV) nucleic acid testing has long compromised result comparability and global outbreak response. Here, we established a national reference material system derived from intact, inactivated CHIKV particles-authentically mirroring the entire clinical workflow. Covering both Asian and East/Central/South African (ECSA) genotypes, this system mitigates false-negative risks caused by viral genetic diversity. Assigned via multi-laboratory dPCR and validated across nine commercial kits, it demonstrated 100% concordance, ≥95% detectability at LoD, and coefficient of variation (CV) <5%. This traceable, genotype-inclusive, workflow-authentic benchmark enables, for the first time, unified performance alignment for regulatory review, manufacturer quality control, and inter-laboratory comparison. It fills a critical gap in domestic quality assurance while providing a technical template for future WHO standardization efforts. Widespread adoption will accelerate reliable diagnostics, strengthen surveillance comparability, and support timely clinical decisions in both endemic and importation-prone settings.
The profiles of phenolic acids and flavan-3-ols for the selected Chinese red wines and the potential of using phenolic acids and flavan-3-ols to differentiate the geographic origin and grape variety of wines from China are investigated in this study. Significant differences and markers could be found according to the geographical origin and grape variety. Through a canonical discriminant analysis a good differentiation was developed according to the geographic origin or grape variety, and the accuracy of the discriminant model was 88.9% and 100%, respectively. According to the phenolic acid and flavan-3-ols profiles of the wine samples and good differentiation in the region and the variety discriminant analysis, minimal fraudulent claims were noted for the Chinese red wines investigated.This study provides some help for the protection of geographical origin and monovarietal wine claims.
Mesoporous multiwalled carbon nanotubes/titanium dioxide (CNTs/TiO2) nanocomposites with low loading amounts (0–0.5 wt%) of CNTs embedded inside mesoporous TiO2 aggregates has been prepared by a simple one-pot hydrothermal method using titanium sulfate as titanium source. The as-prepared CNTs/TiO2 samples are carefully characterized, analyzed and discussed. In contrast to previous reports with high CNT loading, our results indicate that a low CNT loading slightly influences the textural properties (including crystallite size, degree of crystallinity, specific surface areas, and pore volume etc.) and UV-light absorption of the mesoporous TiO2 aggregates. The SEM and TEM results demonstrate that the CNTs are mostly embedded in the mesoporous TiO2 aggregates. Moreover, chemical bonds are formed at the interface between CNTs and TiO2, which is confirmed by the Raman, IR and XPS analyses. Significantly, we point out that PL analysis in terms of intensity of PL signals seems to not be a reliable way to monitor the recombination rate in the CNTs/TiO2 composite, due to the quenching effect of CNTs. Instead, the analysis of transient photocurrent responses is introduced, which definitely reflects CNTs as fast electron transfer channels in chemically-bonded CNTs/TiO2 composites with low CNT loading. Notably, the positive synergy effects of CNTs and TiO2 depend on both the CNT loading amount and the state of interfacial contacts. In our study, only these chemically bonded CNTs/TiO2 nanocomposites with appropriate loading amounts (<0.1 wt%) favor the separation of photogenerated electron-hole pairs and decrease their recombination rate and thus display significantly enhanced photocatalytic activity for degrading acetone in air under UV irradiation, as compared with pristine TiO2 counterparts and commercial P25 photocatalyst. In contrast, a high CNT loading (>0.1 wt%) results in a decrease in photocatalytic activity; a simple mechanical mixing of CNTs and TiO2 without forming chemical bonds at the interface also results in inferior photocatalytic performance.
Permanent magnet synchronous motors (PMSMs) has been gradually applied to space electromechanical products with high-precision and high-stability, the influence of drive circuit on drive performance has attracted more attention. Traditional control strategies for PMSMs are fed by inverter, which can lead to torque ripple due to the chopping of its switching devices, thus limiting the scope of their application. This paper studies the high-precision linear drive circuit based on power operational amplifier for the three-phase open-winding permanent magnet synchronous motor (OW-PMSM), and designs both single-ended and double-ended drive circuits. Based on simulation software PSIM, a closed-loop simulation system of OW-PMSM is established, and the correctness of the drive circuits is simulated and verified. In addition, the performance of single-ended and double-ended drive circuits is compared, which lays a foundation for the application of three-phase OW-PMSMs in high-precision drive control in aerospace.
Potassium (K+) is a macronutrient for plant growth and development. Although a number of K-transporters are encoded in various plant genomes, functional characterization of these transport genes have lagged behind of genomic information in crop plants. In rice genome, a large expansion of high-affinity K-transporters (HAKs/KUPs/KTs) has been identified as compared to those in Arabidopsis genome suggesting a functional diversity of these transporters in cereals. We report here the functional characterization of a HAK member, OsHAK3, in rice using CRISPR-assisted genetic analysis. Expression of OsHAK3 was mainly found in roots and its protein was targeted to the plasma membrane. Loss of function of OsHAK3 led to a reduction of K+ uptake rate and K+ content, consistent with the finding that mutant plants became stunted under low-K+ conditions. In addition, the growth of Oshak3 mutants was more sensitive to salt stress due to altered K/Na ratio in the plants. Together, our data demonstrate that OsHAK3 plays a crucial role in K+ homeostasis, especially under K+-limited conditions and when plants face salinity stress.
