426 research outputs found
Customization design method for complex product systems based on a meta-model
In order to effectively reuse the design knowledge of product family life cycle development and support holistic and rapid individual product design, this article presents a new meta-model-based systemic customization design method for complex product systems within a product-pedigree. The proposed method aims to synthetically analyze the common and adaptive customer demands and product features of a product-pedigree of complex product systems and to quickly respond to the changing demands based on knowledge accumulation in the field of customization design. The key to implement such a method is (1) to construct a product-pedigree-oriented product meta-model with a four-layered architecture where it is possible to achieve a high degree of abstraction of product and (2) to develop a special technique for configuring the meta-model of the complex product systems. We have tested the proposed method with the rapid design of product-pedigree of a high-speed train’s bogies as an illustrative example. In this work, a rapid customization design prototype system has been developed and applied to the design of a high-speed train’s bogie to illustrate how to construct a product meta-model and how to conduct configuration design on different layers and variant design for generating new products
Recent progress in atomically precise Ag/Cu-based hydride clusters
Owing to advantages in synthesis, separation, structure determination, and low cost (compared to noble metal nanoclusters), Ag/Cu hydride clusters (and their alloys) have received increasing research interest in recent decades and have shown great potential in mediating reduction reactions and H2 storage applications. The atomic precision of the Ag/Cu hydride clusters with the combination of single-crystal X-ray diffraction, 1/2H nuclear magnetic resonance, electrospray ionization mass spectrometry, density functional theory, and particularly, single-crystal neutron diffraction, has provided pivotal information regarding its structural characteristics, facilitating a deep understanding of the inherent bonding principles therein. This review summarizes the research progress of atomically precise Ag/Cu hydride clusters (and their alloys) over the past three years (2021–2023), mainly focusing on the synthesis, structure analysis, and catalytic applications of the hydride clusters. We believe that this review can benefit the future design of different types of metal hydride clusters and aid in their application in various redox reactions
Effect of Peripheral Administration of Kisspeptin-10 on Dynamic LH Secretion in Prepubertal Ewes
The aim of the present study was to clarify the effect of kisspeptin-10 on LH secretion in prepubertal ewes. In experiment 1, prepubertal ewes fitted with indwelling jugular catheters were randomly assigned to receive 0, 0.5, 1 or 2 mg of kisspeptin-10 dissolved in saline, and serial blood samples were collected at 15-min intervals for 180 min to analyze the response curves of LH after injection. In experiment 2, prepubertal ewes fitted with indwelling jugular catheters were injected with 0 or 1 mg of kisspeptin-10 dissolved in saline and the injection was repeated 3 times at 1 h interval and serial blood samples were collected at 15-min intervals for 210 min to analyze the response curves of LH after injection. The results showed that single intravenous administration of 0.5, 1 and 2 mg of kisspeptin-10 all could significantly increased LH secretion in prepubertal ewes, and the effect of 1 and 2 mg of kisspeptin-10 on LH secretion was higher than that of 0.5 mg group. The results also showed that repeated intravenous administration of kisspeptin-10 could effectively increase LH secretion and repeated administration did not influence the effect of kisspeptin-10 on LH secretion in prepubertal ewe. In conclusion, the present study indicated that single or repeated intravenous administration of kisspeptin-10 could effectively increase LH secretion in prepubertal ewes
Deep Learning-Enabled Fully Automated Pipeline System for Segmentation and Classification of Single-Mass Breast Lesions Using Contrast-Enhanced Mammography: A Prospective, Multicentre Study
Background
Breast cancer is the leading cause of cancer-related deaths in women. However, accurate diagnosis of breast cancer using medical images heavily relies on the experience of radiologists. This study aimed to develop an artificial intelligence model that diagnosed single-mass breast lesions on contrast-enhanced mammography (CEM) for assisting the diagnostic workflow. Methods
A total of 1912 women with single-mass breast lesions on CEM images before biopsy or surgery were included from June 2017 to October 2022 at three centres in China. Samples were divided into training and validation sets, internal testing set, pooled external testing set, and prospective testing set. A fully automated pipeline system (FAPS) using RefineNet and the Xception + Pyramid pooling module (PPM) was developed to perform the segmentation and classification of breast lesions. The performances of six radiologists and adjustments in Breast Imaging Reporting and Data System (BI-RADS) category 4 under the FAPS-assisted strategy were explored in pooled external and prospective testing sets. The segmentation performance was assessed using the Dice similarity coefficient (DSC), and the classification was assessed using heatmaps, area under the receiver operating characteristic curve (AUC), sensitivity, and specificity. The radiologists’ reading time was recorded for comparison with the FAPS. This trial is registered with China Clinical Trial Registration Centre (ChiCTR2200063444). Findings
The FAPS-based segmentation task achieved DSCs of 0.888 ± 0.101, 0.820 ± 0.148 and 0.837 ± 0.132 in the internal, pooled external and prospective testing sets, respectively. For the classification task, the FAPS achieved AUCs of 0.947 (95% confidence interval [CI]: 0.916–0.978), 0.940 (95% [CI]: 0.894–0.987) and 0.891 (95% [CI]: 0.816–0.945). It outperformed radiologists in terms of classification efficiency based on single lesions (6 s vs 3 min). Moreover, the FAPS-assisted strategy improved the performance of radiologists. BI-RADS category 4 in 12.4% and 13.3% of patients was adjusted in two testing sets with the assistance of FAPS, which may play an important guiding role in the selection of clinical management strategies. Interpretation
The FAPS based on CEM demonstrated the potential for the segmentation and classification of breast lesions, and had good generalisation ability and clinical applicability. Funding
This study was supported by the Taishan Scholar Foundation of Shandong Province of China (tsqn202211378), National Natural Science Foundation of China (82001775), Natural Science Foundation of Shandong Province of China (ZR2021MH120), and Special Fund for Breast Disease Research of Shandong Medical Association (YXH2021ZX055)
Screening for Anti-Inflammation Quality Markers of Lianhua Qingwen Capsule Based on Network Pharmacology, UPLC, and Biological Activity
Influenza is a common respiratory infectious disease. In China, Lianhua Qingwen capsule (LHQWC), a drug with significant clinical efficacy and few side effects, is commonly used to treat influenza. However, the composition of LHQWC is complicated, and currently used quality control methods cannot ensure its consistency. In this study, combined with its clinical efficacy, the targets of LHQWC were screened using network pharmacology. Then, anti-inflammation quality markers of LHQWC were screened and judged by combined chemical with biological evaluation. Cyclooxygenase-2 (COX-2) was identified as one of the main targets of the anti-inflammatory activity of LHQWC. The rate of inhibition of COX-2 by different batches of LHQWC was determined. Furthermore, seven components of LHQWC were identified. The potential quality markers were screened by spectral-effect relationship. As a result, chlorogenic acid, isochlorogenic acid B, and isochlorogenic acid C were identified and confirmed as anti-inflammatory quality markers of LHQWC. We hope that these findings provide a scientific basis for the accurate quality control of LHQWC and serve as a reference for the quality control of other drugs
A new tapered semiconductor laser with integrated multimode interference coupler
A new tapered semiconductor laser with an integrated multimode interference coupler is presented in this paper. The seed source of the new laser is a multimode interference coupler semiconductor laser, which overcomes the limitations imposed by the relationship between single mode output and gain medium volume in the ridged waveguide region. The simulation results show that the multi-mode interference coupler can effectively provide a spatial single-mode seed light source for the tapered output waveguide, and the tapered output waveguide of the tapered semiconductor laser can also effectively reduce the optical power density of the output laser, which verifies the feasibility of the design scheme and provides a new idea for the design of high beam quality and high power tapered semiconductor laser
Exosomes and Their Application as Drug Delivery System in Cancer Therapy
Exosomes are extracellular vesicles naturally released from cells. Exosomes from different sources play different roles in cellular component exchange, signal transduction, and pathological development. Exosomes have distinct biological characteristics such as low immunogenicity, easy uptake by cells, crossing the blood-brain barrier, natural targeting, and easy modification. Many studies show that exosomes as drug carriers have a great application prospect in cancer therapy. In this review, we review the biogenesis, origin, biological characteristics of exosomes, and the exosome drug delivery system and its application for cancer therapy are summarized to provide a reference for the study of exosomes
The regional neuronal activity in left posterior middle temporal gyrus is correlated with the severity of chronic aphasia
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