55 research outputs found
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)
“Adjust Zang and arouse spirit” electroacupuncture ameliorates cognitive impairment by reducing endoplasmic reticulum stress in db/db mice
IntroductionDiabetic cognitive impairment (DCI) is a chronic complication of the central nervous system (CNS) caused by diabetes that affects learning and memory capacities over time. Recently, acupuncture has been shown to improve cognitive impairment in streptozotocin-induced diabetic rats. However, the effects of electroacupuncture on DCI and its underlying mechanism have not yet been elucidated in detail. MethodsIn this study, we used db/db mice as DCI animal models which showed low cognitive, learning and memory functions. Electroacupuncture significantly ameliorated DCI, which is reflected by better spatial learning and memory function using behavioral tests. The db/db mice with cognitive impairment were randomly divided into a model group (Mod) and an electroacupuncture treatment group (Acup), while db/m mice were used as a normal control group (Con). First, the mice were subjected to behavioural tests using the Morris water maze (MWM), and body weight, blood glucose, insulin, triglycerides (TG) and total cholesterol (TC) were observed; HE, Nissl, and TUNEL staining were used to observe the morphological changes and neuronal apoptosis in the mice hippocampus; Finally, Western blot and rt-PCR were applied to detect the essential proteins and mRNA of ERS and insulin signalling pathway, as well as the expression levels of Tau and Aβ.ResultsElectroacupuncture significantly ameliorated DCI, which is reflected by better spatial learning and memory function using behavioral tests. Moreover, electroacupuncture attenuated diabetes-induced morphological structure change, neuronal apoptosis in the hippocampus of db/db mice. Our results revealed that electroacupuncture could regulate the expression levels of Tau and Aβ by improving hippocampal ERS levels in db/db mice, inhibiting JNK activation, attenuating IRS1 serine phosphorylation, and restoring normal transduction of the insulin signaling pathway.DiscussionIn summary, ERS and insulin signaling pathway paly causal roles in DCI development. Electroacupuncture can significantly alleviate the pathogenesis of DCI, improve mice's learning and memory ability, and improve cognitive dysfunction. This study adds to our understanding of the effect of acupuncture on DCI and opens the door to further research on DCI
Calculation of the wellbore temperature and pressure distribution during supercritical CO2 fracturing flowback process
Trends of Phase I Clinical Trials of New Drugs in Mainland China Over the Past 10 Years (2011–2020)
Background: In recent years, the number of clinical trials initiated in China has increased rapidly. The aim of this study was to overview the changing landscape of phase I clinical trials in mainland China from 2011 to 2020.Methods: We analyzed phase I clinical trials registered on 3 websites including the Chinese Clinical Trial Registry, ClinicalTrials.gov, and the China National Medical Products Administration Center for Drug Evaluation platform.Findings: A total of 2,842 phase I clinical trials were posted from January 1, 2011, to December 31, 2020. The overall number of clinical trials for innovative drugs was 1,497, accounting for half of all the phase I clinical trials (53%). Among these 1,486 innovative drug clinical trials, 924 were newly tested drugs with an average annual growth rate of 59%. Biological drug research increased significantly from 22.6% during 2011–2015 to 33.3% during 2016–2020. These principal investigators (PIs) of these clinical trials were mainly from Beijing (n = 871), followed by Shanghai (n = 496) and Jiangsu (n = 281). As for the therapeutic area of phase I clinical trials, cancer took up the most percentage of all the clinical trials (35%), followed by infectious disease (9%), nervous system disease (9%), etc. Most phase I clinical trials are conducted on healthy volunteers (n = 1,642, 57.8%), some cancer drugs are conducted in patients with cancer (n = 846, 29.8%), and only a few clinical trials were conducted in the elderly (n = 7). Among these clinical trials of the newly tested innovative drugs, the first in human (FIH) clinical trials accounted for 82% (744), and the First in Chinese (FIC) clinical trials only took up 18% (167). Only a small number of drugs could be made the transition to phase II (n = 207, 22%). In addition, despite the number of newly tested drugs during 2011–2015 (n = 163) was much less than that in 2016–2020 (n = 761), the percentage of drugs that could enter into phase II clinical trials in 2011–2015 (34%) was higher than that in 2016–2020 (20%).Conclusion: In the past 10 years, the development of phase I clinical trials has achieved great progress in mainland China due to the novel design and drug innovation policy. Nevertheless, future efforts are needed to make for improving the phase transition success rate of innovative drugs.</jats:p
A study of the freeze-drying process and quality evaluation of <i>Angelica sinensis</i>
Abstract
The freeze-drying process of Angelica sinensis (Oliv.) Diels was studied and evaluated. Using a single factor investigation, drying temperature and pressure were determined as the main factors affecting the drying process. The central composite design (CCD) combined with response surface method was employed to optimize the drying process. Optimal conditions were determined to be 52 Pa, 63 °C, and a slice thickness of 5 mm. Subsequently, samples were compared in terms of chemical constituents, microstructure, and in vitro absorption profiles under different drying operations. The freeze-drying process was effective for the preservation of ferulic acid (1.82 mg/g), Z-ligustilide (13.91 mg/g), and other compositions. The porous and loose characteristic structure enabled rapid release of ferulic acid (71%, 60 min) and Z-ligustilide (32%, 60 min). Therefore, the freeze-drying method is a reasonable and efficient drying method for the dehydration of A. sinensis.</jats:p
Proppant Transport Characteristics in Tortuous Fractures Induced by Supercritical CO2 Fracturing
Supercritical CO2 fracturing is an important development trend to reach the goal of ''dual carbon'' and avoid the problem that hydraulic fracturing is influenced by water resource. In order to clarify the transport characteristics of proppant in the fractures induced by supercritical CO2 fracturing, this paper reconstructs the fracture surface of rock samples after supercritical CO2 fracturing using the laser morphological scanning technology, and establishes a model of proppant carrying and transport of supercritical CO2 in tortuous fractures on the basis of CFD-DEM method. In addition, the transport and placement characteristics of proppant in tortuous fractures are analyzed by comparing with flat fractures, and the effects of proppant density, injection rate of proppant carrying liquid, proppant concentration and other key parameters on proppant transport and distribution in fractures are investigated. And the following research results are obtained. First, compared with those in flat fractures, the flow paths of the proppant carrying supercritical CO2 liquid in tortuous fractures are tortuous and diverse, and the proppant presents stronger fluctuations and jumps laterally and vertically during its transport. Second, the proppant placement in tortuous fractures morphologically presents a wavy or even clustered non-uniform distribution. Third, low-density proppant has a better pass-ability in tortuous fractures, and the high injection rate can reduce the influence of tortuous fracture structure on proppant blocking. Fourth, if the concentration of injected proppant in the tortuous fracture is too low, good fracturing support effect cannot be achieved, and the optimal value under the simulation conditions in this paper is around 3%. In conclusion, the simulation results are of important theoretical and engineering significance to understanding the mechanism of proppant blocking in the pumping process of proppant carrying liquid for supercritical CO2 fracturing and optimizing the field fracturing design
Research on the Design of Carbon-Neutralized Building in Rural China: A Case Study of “Impression of Yucun”
Energy conservation and emission reduction in rural buildings is essential to China’s response to climate change. Within the context of China’s ‘dual carbon’ initiative and the overarching goal of a ‘zero carbon countryside’, the first rural carbon-neutral building in China—‘Impression of Yucun’ was established in Anji County, Zhejiang Province. Accordingly, this study investigates building carbon-neutral design, calculating and analyzing the carbon emissions and offsets facilitated by carbon neutrality technology throughout the buildings’ life cycle. In addition, the comprehensive benefits of the buildings are evaluated from both technical and economic perspectives. The implementation pathway for rural carbon-neutral buildings is also explored. The results demonstrate that through the judicious application of carbon neutrality technology design, the inherent carbon emissions of the buildings amount to 120.91 t and the energy consumption during the operational phase of the building is 64,284.4 kWh/a, correlating to carbon emissions of 33.72 t. The case can theoretically reduce carbon emissions by 65.64 tCO2 annually by implementing carbon offset measures. Considering photovoltaic cell decay, the building can achieve a carbon-neutral state for the first time in the fifth year of operation, with a net carbon emission of −5.58 tCO2. Simultaneously, the investment in photovoltaic systems can be recouped between the seventh and ninth years of operation. This study can offer methodological reference and data support for designing and evaluating carbon-neutral buildings
Model Predictive Control for Hybrid Electric Vehicle Platooning Using Slope Information
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