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ObjectivesTo investigate the value of contrast-enhanced computer tomography (CT)-based on radiomics in discriminating high-grade and low-grade hepatocellular carcinoma (HCC) before surgery.MethodsThe retrospective study including 161 consecutive subjects with HCC which was approved by the institutional review board, and the patients were divided into a training group (n = 112) and test group (n = 49) from January 2013 to January 2018. The least absolute shrinkage and selection operator (LASSO) was used to select the most valuable features to build a support vector machine (SVM) model. The performance of the predictive model was evaluated using the area under the curve (AUC), accuracy, sensitivity, and specificity.ResultsThe SVM model showed an acceptable ability to differentiate high-grade from low-grade HCC, with an AUC of 0.904 in the training dataset and 0.937 in the test dataset, accuracy (92.2% versus 95.7%), sensitivity(82.5% versus 88.0%), and specificity (92.7% versus 95.8%), respectively.ConclusionThe machine learning-based radiomics reflects a better evaluating performance in differentiating HCC between low-grade and high-grade, which may contribute to personalized treatment.

Background: Eukaryotic genes contain introns that are removed by the spliceosomal machinery during mRNA maturation. Introns impose a huge energetic burden on a cell; therefore, they must play an essential role in maintaining genome stability and/or regulating gene expression. Many genes (> 50%) in Plasmodium parasites contain predicted introns, including introns in 5′ and 3′ untranslated regions (UTR). However, the roles of UTR introns in the gene expression of malaria parasites remain unknown. Methods: In this study, an episomal dual-luciferase assay was developed to evaluate gene expression driven by promoters with or without a 5′UTR intron from four Plasmodium yoelii genes. To investigate the effect of the 5′UTR intron on endogenous gene expression, the pytctp gene was tagged with 3xHA at the N-terminal of the coding region, and parasites with or without the 5′UTR intron were generated using the CRISPR/Cas9 system. Results: We showed that promoters with 5′UTR introns had higher activities in driving gene expression than those without 5′UTR introns. The results were confirmed in recombinant parasites expressing an HA-tagged gene (pytctp) driven by promoter with or without 5′UTR intron. The enhancement of gene expression was intron size dependent, but not the DNA sequence, e.g. the longer the intron, the higher levels of expression. Similar results were observed when a promoter from one strain of P. yoelii was introduced into different parasite strains. Finally, the 5′UTR introns were alternatively spliced in different parasite development stages, suggesting an active mechanism employed by the parasites to regulate gene expression in various developmental stages. Conclusions: Plasmodium 5′UTR introns enhance gene expression in a size-dependent manner; the presence of alternatively spliced mRNAs in different parasite developmental stages suggests that alternative slicing of 5′UTR introns is one of the key mechanisms in regulating parasite gene expression and differentiation. [ABSTRACT FROM AUTHOR]

Non-convex tubes that have superior energy absorption potential may expand and deform unstable during impact, limiting energy absorption. The bamboo node can strengthen bamboo by resisting expansion. Therefore, bulkhead proportional distribution of bionic non-convex (BPDBN) tubes, an integrator of them, may present more efficient energy absorption performance. This research proposed to investigate the effect of geometrical parameters on the crashworthiness characteristics of BPDBN tubes. The position of bulkheads was assumed to vary according to the positive proportional function primarily determined by proportional coefficient k. The dynamic response was evaluated by the initial peak force (IPF), specific energy absorption (SEA), and crush force efficiency (CFE). Multi-objective optimization method was utilized to further improve the energy absorption performance. The optimal design lowered the IPF (34.00%), increased the SEA (37.16%) and the CFE (42.95%). This paper emphasizes that optimizing the geometrical parameters and the bulkhead distance proportion can significantly improve the crashworthiness performance of BPDBN tubes. [ABSTRACT FROM AUTHOR]

Direct‐current (DC) distribution lines are mostly underground cables, with the highest probability of single pole to ground fault among various faults. However, the topology of DC distribution networks is flexible and variable, and existing fault location technologies cannot achieve both high accuracy and good adaptability. A fault section location method for single pole to ground fault in DC distribution lines based on steady‐state zero‐mode current direction is proposed. First, a unified zero‐mode equivalent model for the DC distributed system in the non‐effectively grounded system is established. Then the directional difference in zero‐mode current between the fault and non‐fault sections in the zero‐mode network is fully explored when a single pole to ground fault occurs. Next, a fault section location criterion based on the direction of the steady‐state zero‐mode current is proposed to effectively identify the single‐pole grounded fault section. The feasibility of the proposed fault section location method under different fault conditions is verified based on the PSCAD/EMTDC software. In addition, the simulations show that the proposed method is suitable in the non‐effectively grounded system, and has low requirements for sampling frequency and data processing, with strong resistance to transition resistance. [ABSTRACT FROM AUTHOR]

Due to the unique structures, van der Waals (vdW) materials have advantages over traditional magnetothermal materials in manipulating magnetothermal properties through structural modification and in cooling applications in nanodevices. Here, we study the magnetothermal properties of vdW ferromagnet Fe5GeTe2 with Curie temperature around room temperature. The results show that Fe5GeTe2 is a second-order magnetic phase transition material, and its in-plane and out-of-plane values of relative cooling power are large up, respectively, to 299.3 and 269.2 J/kg for a field change of 5 T. Compared to other vdW materials reported, Fe5GeTe2 has the greatest potential for room-temperature magnetic cooling applications. [ABSTRACT FROM AUTHOR]

Due to the unique structures, van der Waals (vdW) materials have advantages over traditional magnetothermal materials in manipulating magnetothermal properties through structural modification and in cooling applications in nanodevices. Here, we study the magnetothermal properties of vdW ferromagnet Fe5GeTe2 with Curie temperature around room temperature. The results show that Fe5GeTe2 is a second-order magnetic phase transition material, and its in-plane and out-of-plane values of relative cooling power are large up, respectively, to 299.3 and 269.2 J/kg for a field change of 5 T. Compared to other vdW materials reported, Fe5GeTe2 has the greatest potential for room-temperature magnetic cooling applications. [ABSTRACT FROM AUTHOR]

Correction for 'Super-adsorbent hydrogel for removal of methylene blue dye from aqueous solution' by Xiao-Sai Hu et al., J. Mater. Chem. A, 2018, 6, 17612–17624, https://doi.org/10.1039/C8TA04722G. [ABSTRACT FROM AUTHOR]

[Display omitted] • A sorting strategy was proposed to improve the pyrolytic homogeneity of MSW. • An index (C) was established to quantify the sorting performance for Ea and logA. • The strategy outperformed traditional ones in pyrolytic homogeneity enhancement. • M3 model showed optimal C_Ea (1578.30 kJ/mol) and C_logA (93.11 -log min). Heterogeneity of pyrolytic parameters in municipal solid waste (MSW) significantly hinders its waste-to-energy efficiency. So far, hardly any light has been shed on current pyrolytic heterogeneity conditions or feasible pyrolytic homogeneity enhancement approaches of MSW. Accordingly, pyrolytic properties (E a and logA) of 130 MSW samples in 6 categories were collected from literature. A kinetic parameters clustering-based sorting strategy for MSW was proposed. A so-called C index was established to compare their sorting performance for E a and logA against two traditional sorting strategies (substance categorization and density clustering). Results showed that the proposed sorting strategies outperformed the traditional ones in pyrolytic homogeneity enhancement, where the optimal C_E a and C_logA reached 1578.30 kJ/mol and 93.11 -log min. Among investigated clustering methods, k-means clustering outperformed hierarchical clustering, which could be attributed to its adaptability to the sample structure. Future perspectives involving data set expansion, model framework development, and downstream technologies matching were also discussed. The index C established in this study can be used to evaluate other clustering models. [ABSTRACT FROM AUTHOR]

The practical implementation of massive multi-user multi-input–multi-output (MU-MIMO) downlink communication systems power amplifiers that are energy efficient; otherwise, the power consumption of the base station (BS) will be prohibitive. Constant envelope (CE) precoding is gaining increasing interest for its capability to utilize low-cost, high-efficiency nonlinear radio frequency amplifiers. Our work focuses on the topic of CE precoding in massive MU-MIMO systems and presents an efficient CE precoding algorithm. This algorithm uses an alternating minimization (AltMin) framework to optimize the CE precoded signal and precoding factor, aiming to minimize the difference between the received signal and the transmit symbol. For the optimization of the CE precoded signal, we provide a powerful approach that integrates the majorization-minimization (MM) method and the fast iterative shrinkage-thresholding (FISTA) method. This algorithm combines the characteristics of the massive MU-MIMO channel with the second-order Taylor expansion to construct the surrogate function in the MM method, in which minimizing this surrogate function is the worst-case of the system. Specifically, we expand the suggested CE precoding algorithm to involve the discrete constant envelope (DCE) precoding case. In addition, we thoroughly examine the exact property, convergence, and computational complexity of the proposed algorithm. Simulation results demonstrate that the proposed CE precoding algorithm can achievean uncoded biterror rate (BER) performance gain of roughly 1 dB compared to the existing CE precoding algorithm and has an acceptable computational complexity. This performance advantage also exists when it comes to DCE precoding. [ABSTRACT FROM AUTHOR]

To analyse the MRI-based radiomics and delta-radiomics features to establish radiomics models for predicting the radiographic progression of osteoarthritis (OA). The data used in this research come from the dataset of the FNIH Biomarker Consortium Project within the Osteoarthritis Initiative (OAI). 565 participants randomly divided into training and validation groups at a 7:3 ratio. The training cohort consisted of 395 participants and included 202 cases. The validation cohort consisted of 170 participants and included 87 cases. Least absolute shrinkage and selection operator (LASSO) was used for feature selection. Support vector machine (SVM) was used to establish radiomics models and clinical and biomarker models for predicting the radiographic progression of OA. The predictive ability of the model was evaluated by the area under the curve (AUC). The baseline, 24 M, Delta, and two combination radiomics models (Baseline and Delta, 24 M and Delta) all showed good predictive performance in the training and validation cohorts, with the combination model exhibiting the best performance. In the training cohort, the AUCs were 0.851 (95% CI: 0.812–0.890), 0.825 (95% CI: 0.784–0.865), 0.804 (95% CI: 0.761–0.847), 0.892 (95% CI: 0.860–0.924) and 0.884 (95% CI: 0.851–0.917), respectively. The AUCs in the validation cohort were 0.741 (95% CI: 0.667–0.814), 0.786 (95% CI: 0.716–0.856), 0.745 (95% CI: 0.671–0.819), 0.781 (95% CI: 0.711–0.851) and 0.802 (95% CI: 0.736–0.869), respectively. As compared, the clinical and biomarker models have AUC < 0.74. The DeLong test showed that the predictive performance of the radiomics models in the training and validation cohorts was significantly better than that of the clinical and biomarker models (P < 0.001). The MRI-based radiomics models of the patella all showed good predictive performance performed better than the clinical and biomarker models in predicting the radiographic progression of OA. Delta radiomics can improve the predictive performance of the single time model, the combined model of 24 M and Delta provided the best predictive performance. [ABSTRACT FROM AUTHOR]

Pleckstrin homeolike domain, family A, member 1 (PHLDA1) is a multifunctional protein that plays diverse roles in A variety of biological processes, including cell death, and hence its altered expression has been found in different types of cancer. Although studies have shown a regulatory relationship between p53 and PHLDA1, the molecular mechanism is still unclear. Especially, the role of PHLDA1 in the process of apoptosis is still controversial. In this study, we found that the expression of PHLDA1 in human cervical cancer cell lines was correlated with the up-expression of p53 after treatment with apoptosis-inducing factors. Subsequently, the binding site and the binding effect of p53 on the promoter region of PHLDA1 were verified by our bioinformatics data analysis and luciferase reporter assay. Indeed, we used CRISPR-Cas9 to knockout the p53 gene in HeLa cells and further confirmed that p53 can bind to the promoter region of PHLDA1 gene, and then directly regulate the expression of PHLDA1 by recruiting P300 and CBP to change the acetylation and methylation levels in the promoter region. Finally, a series of gain–of–function experiments further confirmed that p53 re-expression in HeLap53-/- cell can up-regulate the reduction of PHLDA1 caused by p53 knockout, and affect cell apoptosis and proliferation. Our study is the first to explore the regulatory mechanism of p53 on PHLDA1 by using the p53 gene knockout cell model, which further proves that PHLDA1 is a target-gene in p53-mediated apoptosis, and reveals the important role of PHLDA1 in cell fate determination. [ABSTRACT FROM AUTHOR]