Crosslinked fluoropolymers exhibiting superior high-temperature energy density and charge-discharge efficiency

Superior high-temperature discharged energy densities in comparison to those of the current dielectric polymers have been demonstrated in the crosslinked fluoropolymers

CT-based Subchondral Bone Microstructural Analysis in Knee Osteoarthritis via MR-Guided Distillation Learning

Background: MR-based subchondral bone effectively predicts knee osteoarthritis. However, its clinical application is limited by the cost and time of MR. Purpose: We aim to develop a novel distillation-learning-based method named SRRD for subchondral bone microstructural analysis using easily-acquired CT images, which leverages paired MR images to enhance the CT-based analysis model during training. Materials and Methods: Knee joint images of both CT and MR modalities were collected from October 2020 to May 2021. Firstly, we developed a GAN-based generative model to transform MR images into CT images, which was used to establish the anatomical correspondence between the two modalities. Next, we obtained numerous patches of subchondral bone regions of MR images, together with their trabecular parameters (BV / TV, Tb. Th, Tb. Sp, Tb. N) from the corresponding CT image patches via regression. The distillation-learning technique was used to train the regression model and transfer MR structural information to the CT-based model. The regressed trabecular parameters were further used for knee osteoarthritis classification. Results: A total of 80 participants were evaluated. CT-based regression results of trabecular parameters achieved intra-class correlation coefficients (ICCs) of 0.804, 0.773, 0.711, and 0.622 for BV / TV, Tb. Th, Tb. Sp, and Tb. N, respectively. The use of distillation learning significantly improved the performance of the CT-based knee osteoarthritis classification method using the CNN approach, yielding an AUC score of 0.767 (95% CI, 0.681-0.853) instead of 0.658 (95% CI, 0.574-0.742) (p<.001). Conclusions: The proposed SRRD method showed high reliability and validity in MR-CT registration, regression, and knee osteoarthritis classification, indicating the feasibility of subchondral bone microstructural analysis based on CT images.Comment: 5 figures, 4 table

Silver spoon effects of hatching order in an asynchronous hatching bird

The silver spoon hypothesis proposes that individuals which develop under favourable conditions will gain fitness benefits throughout their lifetime. Hatching order may create a considerable size hierarchy within a brood and lead to earlier-hatched nestlings having a competitive advantage over their siblings, which has been illustrated in some studies. However, there have been few explorations into the effect on subsequent generations. Here, using a 15-year-long study, we investigated the long-term fitness consequence of hatching order in the endangered crested ibis, Nipponia nippon, a species with complete hatching asynchrony. In this study, we found strong support for silver spoon effects acting on hatching order. Compared to later-hatched nestlings, first-hatched nestlings begin reproduction at an earlier age, have higher adult survival rates, possess a longer breeding life span and achieve higher lifetime reproductive success. Interestingly, we found carry-over effects of hatching order into the next generation. Nestlings which hatched earlier and became breeders in turn also produced nestlings with larger tarsus and better body condition. Additionally, we found a positive correlation among life-history traits in crested ibis. Individuals which started reproduction at a younger age were shown to possess a longer breeding life span. And the annual brood size increased with an individual’s breeding life span. This suggests that the earlier-hatched nestlings are of better quality and the ‘silver spoon’ effects of hatching order cover all life-history stages and next generation effects

An enhanced respiratory mechanics model based on double-exponential and fractional calculus

We address mathematical modelling of respiratory mechanics and put forward a model based on double-exponential and fractional calculus for parameter estimation, model simulation, and evaluation based on actual data. Our model has been implemented on a publicly available executable code with adjustable parameters, making it suitable for different applications. Our analysis represents the first application of fractional calculus and double-exponential modelling to respiratory mechanics, and allows us to propose a hybrid model fitting experimental data in different ventilation modes. Furthermore, our model can be used to study the mechanical features of the respiratory system, improve the safety of ventilation techniques, reduce ventilation damages, and provide strong support for fast and adaptive determination of ventilation parameters

Low-Quality Training Data Only? A Robust Framework for Detecting Encrypted Malicious Network Traffic

Machine learning (ML) is promising in accurately detecting malicious flows in encrypted network traffic; however, it is challenging to collect a training dataset that contains a sufficient amount of encrypted malicious data with correct labels. When ML models are trained with low-quality training data, they suffer degraded performance. In this paper, we aim at addressing a real-world low-quality training dataset problem, namely, detecting encrypted malicious traffic generated by continuously evolving malware. We develop RAPIER that fully utilizes different distributions of normal and malicious traffic data in the feature space, where normal data is tightly distributed in a certain area and the malicious data is scattered over the entire feature space to augment training data for model training. RAPIER includes two pre-processing modules to convert traffic into feature vectors and correct label noises. We evaluate our system on two public datasets and one combined dataset. With 1000 samples and 45% noises from each dataset, our system achieves the F1 scores of 0.770, 0.776, and 0.855, respectively, achieving average improvements of 352.6%, 284.3%, and 214.9% over the existing methods, respectively. Furthermore, We evaluate RAPIER with a real-world dataset obtained from a security enterprise. RAPIER effectively achieves encrypted malicious traffic detection with the best F1 score of 0.773 and improves the F1 score of existing methods by an average of 272.5%

Coronary angiography review in 21 children with Kawasaki disease complicated with coronary artery disease

Objective·To analyze the progression of children with severe coronary artery lesions due to Kawasaki disease by coronary artery angiography, and evaluate the diagnostic value of echocardiography in these children.Methods·A retrospective analysis was performed to enroll children with Kawasaki disease whose coronary artery lesions were graded Ⅳ or above from Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, from January 2013 to January 2023. The subjects were required to have received at least 2 times of coronary angiogram, and their clinical and imaging data were collected to analyze the progression of the lesions. Echocardiography results were compared with the results of the coronary angiogram.Results·A total of 21 children were included, including 15 males and 6 females, with a median age at onset of 3 years and 6 months, a median age at initial coronary angiography of 7 years and 11 months, a median interval of 4 years and 5 months between the time of onset and initial angiography, a median age at angiographic review of 9 years and 2 months, and a median interval of 1 year and 3 months between the time of initial angiography and review. Coronary stenosis or occlusion was detected in 13 children in the initial angiography, of whom 6 underwent coronary artery bypass grafting (CABG) and had their angiography reviews 1 year later. The review results showed that the bridging vessels were unobstructed and no obvious stenosis was observed. Fifteen children had progression of the lesions detected by echocardiography in the subsequent follow-up and had their angiogram reviews, of whom 8 had significant progression of the coronary lesions. Intracoronary balloon dilatation was performed in 1 case, and CABG was performed in another case. Sixteen lesions of coronary stenosis or occlusion were detected in the initial angiography in 21 children, while only 1 lesion of coronary stenosis was detected by echocardiography during the same period of time. Twenty-eight medium- to large-sized coronary aneurysms were detected in the initial angiography in the 21 children, and the diameters of the 28 aneurysms measured by echocardiography and coronary angiogram were subjected to the Bland-Altman analysis. The Bland-Altman analysis showed that the difference in maximum diameter between 2 methods was (1.63±2.33) mm, with 95%CI of -2.95‒6.21 mm.Conclusion·Coronary artery lesions due to Kawasaki disease may be progressive; in the children with severe lesions, coronary artery stenosis or occlusion may be missed or misdiagnosed and some errors may exist in the measurement of diameters of aneurysms by echocardiography. Regular review of coronary angiography is needed

Detection of Virus-Related Sequences Associated With Potential Etiologies of Hepatitis in Liver Tissue Samples From Rats, Mice, Shrews, and Bats

Hepatitis is a major global health concern. However, the etiology of 10–20% hepatitis cases remains unclear. Some hepatitis-associated viruses, like the hepatitis E virus, are zoonotic pathogens. Rats, shrews, and bats are reservoirs for many zoonotic pathogens. Therefore, understanding the virome in the liver of these animals is important for the investigation of the etiologies of hepatitis and monitoring the emerging zoonotic viruses. In this study, viral metagenomics and PCR methods were used to investigate viral communities in rats, mice, house shrews, and bats livers. Viral metagenomic analysis showed a diverse set of sequences in liver samples, comprising: sequences related to herpesviruses, orthomyxoviruses, anelloviruses, hepeviruses, hepadnaviruses, flaviviruses, parvoviruses, and picornaviruses. Using PCR methods, we first detected hepatovirus sequences in Hipposideros larvatus (3.85%). We also reported the first detection of Zika virus-related sequences in rats and house shrews. Sequences related to influenza A virus and herpesviruses were detected in liver. Higher detection rates of pegivirus sequences were found in liver tissue and serum samples from rats (7.85% and 15.79%, respectively) than from house shrews. Torque teno virus sequences had higher detection rates in the serum samples of rats and house shrews (52.72% and 5.26%, respectively) than in the liver. Near-full length genomes of pegivirus and torque teno virus were amplified. This study is the first to compare the viral communities in the liver of bats, rats, mice, and house shrews. Its findings expand our understanding of the virome in the liver of these animals and provide an insight into hepatitis-related viruses

Exfoliation of Quasi-Two-Dimensional Nanosheets of Metal Diborides

Metal diborides are a class of ceramic materials with crystal structures consisting of hexagonal sheets of boron atoms alternating with planes of metal atoms held together with mixed character ionic/covalent bonds. Many of the metal diborides are ultrahigh-temperature ceramics such as HfB2, TaB2, and ZrB2, which have melting points above 3000 °C, high mechanical hardness and strength at high temperatures, and high chemical resistance, while MgB2 is a superconductor with a transition temperature of 39 K. Here, we demonstrate that this diverse family of non-van der Waals (vdW) materials can be processed into stable dispersions of quasi-two-dimensional (2D) nanosheets using ultrasonication-assisted exfoliation. We generate quasi-2D nanosheets of the metal diborides AlB2, CrB2, HfB2, MgB2, NbB2, TaB2, TiB2, and ZrB2 and use electron and scanning probe microscopy techniques to characterize their structures, morphologies, and compositions. The exfoliated layers have a distribution of lateral dimensions from tens of nanometers up to several micrometers and a distribution of thicknesses from as low as 2-3 nm up to tens of nanometers, all while retaining their hexagonal atomic structure and chemical composition. We exploit the convenient solution-phase dispersions of exfoliated CrB2 nanosheets to incorporate them directly into polymer composites. In contrast to the hard and brittle bulk CrB2, we find that CrB2 nanocomposites remain very flexible and simultaneously provide increases in the elastic modulus and the ultimate tensile strength of the polymer. The successful liquid-phase production of quasi-2D metal diborides enables their processing using scalable low-temperature solution-phase methods, extending their use to previously unexplored applications, and reveals a new family of non-vdW materials that can be efficiently exfoliated into quasi-2D forms