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Objective: To establish a machine learning-based radiomics model to differentiate between glioma and solitary brain metastasis from lung cancer and its subtypes, thereby achieving accurate preoperative classification. Materials and methods: A retrospective analysis was conducted on MRI T1WI-enhanced images of 105 patients with glioma and 172 patients with solitary brain metastasis from lung cancer, which were confirmed pathologically. The patients were divided into the training group and validation group in an 8:2 ratio for image segmentation, extraction, and filtering; multiple layer perceptron (MLP), support vector machine (SVM), random forest (RF), and logistic regression (LR) were used for modeling; fivefold cross-validation was used to train the model; the validation group was used to evaluate and assess the predictive performance of the model, ROC curve was used to calculate the accuracy, sensitivity, and specificity of the model, and the area under curve (AUC) was used to assess the predictive performance of the model. Results: The accuracy and AUC of the MLP differentiation model for high-grade glioma and solitary brain metastasis in the validation group was 0.992, 1.000, respectively, while the sensitivity and specificity were 1.000, 0.968, respectively. The accuracy and AUC for the MLP and SVM differentiation model for high-grade glioma and small cell lung cancer brain metastasis in the validation group was 0.966, 1.000, respectively, while the sensitivity and specificity were 1.000, 0.929, respectively. The accuracy and AUC for the MLP differentiation model for high-grade glioma and non-small cell lung cancer brain metastasis in the validation group was 0.982, 0.999, respectively, while the sensitivity and specificity were 0.958, 1.000, respectively. Conclusion: The application of machine learning-based radiomics has a certain clinical value in differentiating glioma from solitary brain metastasis from lung cancer and its subtypes. In the HGG/SBM and HGG/NSCLC SBM validation groups, the MLP model had the best diagnostic performance, while in the HGG/SCLC SBM validation group, the MLP and SVM models had the best diagnostic performance. [ABSTRACT FROM AUTHOR]

The crawling process of snakes is known to have fascinating tribological phenomena, whereas investigations on their frictional properties depending on patterned cuticles are insufficient. In this study, we have designed and fabricated biomimetic microstructures inspired by the geometric microunits of Achalinus spinalis cuticle using polyurethane acrylate (PUA) material and performed its tribological analysis. The micro-morphology of this Achalinus-inspired textured polymer surface (AITPS) is characterized by the closely and evenly quasi-rectangular microgrooves, periodically arranged along certain orientations. We have compared the frictional performance of our fabricated AITPS with other competitive microstructure, using a smooth steel ball and commercial clay as an interacting surface. After performing massive friction tests with steel ball and clay, AITPS still maintains good resistance reduction performed compared to the patterned surface with straight microgrooves, which is most likely due to the reduction of actual contact areas at the frictional interface. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The burgeoning growth of the new energy vehicles and aviation industry has escalated the need for energy storage capacitors capable of stable operation in harsh environments. The advent of metal-polyimide complexes has illuminated a novel approach for preparing temperature-resistant capacitors. However, the general application of these metal-polyimide complexes is impeded by the high dielectric loss and low breakdown strength, consequences of main-chain coordination and excessive metal ions content. Herein, our study proposes a novel polyimide-Cu complex material (POP-Cu) predicated on side-chain-type pyridine-Cu coordination, utilizing the structural backbone PMDA-ODA of mature commercial PI (Kapton) with reliable performance. Owing to the high degree of freedom afforded by the side chain with suppressed relaxation activation energy and the long-range electron delocalization formed by d-π coordination, the dielectric constant of this material containing merely 2.7 mol% Cu increases from 3.25 (POPI) to 5.58, while maintaining a remarkably low dielectric loss of 0.0066. Meanwhile, this material exhibits a substantial DC breakdown strength of 436.2 MV·m−1 and a high energy density of 5.42 J·cm−3, coupled with superior mechanical and thermal properties. Even at 150 °C, it retains over 90% of its room-temperature energy density, demonstrating notable dielectric stability under high temperatures. These attributes underscore its promising application for capacitors operating in harsh environments. [ABSTRACT FROM AUTHOR]

Undercooked or raw meat containing cyst-stage bradyzoites and oocyst-contaminated pets are presumed to constitute a major source of human toxoplasmosis. As the geospatial epidemiology of Toxoplasma gondii (T. gondii) infection in livestock, pets, and humans is rarely studied in China, we undertook a geospatial analysis using GIS visualization techniques. The present study retrieved information from the PubMed, China National Knowledge Infrastructure, and Baidu Scholar databases from 1984 up to 2020. All the data about the seroprevalence of T. gondii in livestock (sheep and goats, pigs, cattle and yaks), pets (cats, dogs), and humans in China were collected. Geospatial epidemiology of T. gondii infection in these hosts was performed using GIS. Results revealed that the estimated pooled seroprevalence of T. gondii was ranged from 3.98 to 43.02% in sheep and goats in China, 0.75 to 30.34% in cattle and yaks, 10.45 to 66.47% in pigs, 2.50 to 60.00% in cats, 0.56 to 27.65% in dogs, and 0.72 to 23.41% in humans. The higher seroprevalences of T. gondii were observed in sheep and goats in the districts of Chongqing, Zhejiang, and Beijing. The infection rates of T. gondii in cattle and yaks were higher in Guizhou, Zhejiang, and Chongqing. Also, the pigs from Chongqing and Guizhou were most severely infected with T. gondii. For cats, the districts of Shanxi, Hebei, and Yunnan had higher seroprevalences of T. gondii and, the infections among dogs were higher in Yunnan and Hebei as well. Furthermore, higher infection pressure of T. gondii exists in the districts of Taiwan and Tibet in humans. The geographical and spatial distribution of toxoplasmosis indicated that infection with T. gondii was widely spread in China, with a wide range of variations among the different hosts and regions in the country. Our results suggested that livestock and pets are not only a reservoir for the parasite but also a direct source of T. gondii infection for humans. It is important to control T. gondii infections in these animals that would reduce the risk of toxoplasmosis in humans. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) have been widely used in antibacterial fields due to their excellent antibacterial effects. Here, by using a dietary flavonoid found in edible plants, kaempferol (Kae), as reducing and capping agent, a facile and eco-friendly method was developed to synthesize the uniform and long-term stable silver nanoparticle/kaempferol composites (Kae-AgNPs). Kae-AgNPs were characterized by ultraviolet visible (UV–Vis) spectroscopy, Fourier transform infrared spectrum (FT-IR) spectroscopy, dynamic light scattering (DLS), high resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Kae-AgNPs with a size about 10 nm were synthesized by 0.1 mmol/L Kae. Lower concentration of Kae was shown with smaller Kae-AgNPs due to a few of Kae molecules expected to reduce a small number of Ag+ ions to metallic silver. Aqueous Kae-AgNPs were very stable and could be stably dispersed in water for about two months as evidenced by DLS detection, and the stability was further confirmed by XPS. Antibacterial analysis against Escherichia coli (ATCC 8099) and Staphylococcus aureus (ATCC 6538) strains showed that Kae-AgNPs displayed superior antibacterial effects than AgNPs or Kae alone, and interestingly, much better than that of the analogous nano-silver composites in the previous studies. Moreover, Kae-AgNPs with a low concentration of 2 μg/mL demonstrated highly effective antibacterial activity against E. coli (1 × 106 CFU/mL). The antibacterial mechanisms of Kae-AgNPs included the destruction of the membrane structure of bacteria, leakage of the cell contents, inducing the production of reactive oxygen species (ROS), and eventually resulting in bacteria death. The results suggest that Kae-AgNPs have high efficiency against bacteria, and have the potential to be further developed as promising antibacterial nanocomposites. [ABSTRACT FROM AUTHOR]

In the present study, we investigated the mechanisms underlying the mediation of iron transport by L-type Ca2+ channels (LTCCs) in primary cultured ventral mesencephalon (VM) neurons from rats. We found that co-treatment with 100 µmol/L FeSO4 and MPP+ (1-methyl-4-phenylpyridinium) significantly increased the production of intracellular reactive oxygen species, decreased the mitochondrial transmembrane potential and increased the caspase-3 activation compared to MPP+ treatment alone. Co-treatment with 500 µmol/L CaCl2 further aggravated the FeSO4-induced neurotoxicity in MPP+-treated VM neurons. Co-treatment with 10 µmol/L isradipine, an LTCC blocker, alleviated the neurotoxicity induced by co-application of FeSO4 and FeSO4/CaCl2. Further studies indicated that MPP+ treatment accelerated the iron influx into VM neurons. In addition, FeSO4 treatment significantly increased the intracellular Ca2+ concentration. These effects were blocked by isradipine. These results suggest that elevated extracellular Ca2+ aggravates iron-induced neurotoxicity. LTCCs mediate iron transport in dopaminergic neurons and this, in turn, results in elevated intracellular Ca2+ and further aggravates iron-induced neurotoxicity. [ABSTRACT FROM AUTHOR]

The tracking performance of star sensor degrades seriously under dynamic conditions. To improve the tracking accuracy and efficiency, an attitude tracking method based on unscented Kalman filter (UKF) and singular value decomposition (SVD) is proposed in this paper. The star sensor is modeled as a nonlinear stochastic system, the state of which is attitude quaternion. The quaternion can be estimated by UKF, then the predicted attitude and corresponding star positions are obtained. To ensure the stability of attitude tracking, SVD is applied to obtain the sigma points in UKF continuously. The experimental results indicate that the proposed method yields high accuracy and efficiency in attitude tracking. This method provides a practical approach to ensure the tracking performance of star sensor under dynamic conditions. [ABSTRACT FROM AUTHOR]

Evapotranspiration (ET) is a critical component of the global hydrological cycle, and it has a large impact on water resource management as it affects the availability of freshwater resources. It is important to understand the hydrological cycle for the water resources planning and management. This study used Moderate Resolution Imaging Spectroradiometer (MODIS) satellite derived ET, and potential evapotranspiration (PET) and Tropical Rainfall Measuring Mission (TRMM) satellite derived precipitation datasets to assess the spatial and temporal distributions of ET, PET, and precipitation during the study period at Three Gorges Reservoir (TGR) region. Based on the topographic variations and land-use/land-cover distributions, the study region which includes five counties of Hubei Province and nineteen counties of Chongqing Municipality was divided into four study zones. The ET and precipitation data were evaluated using in situ observations. The ET, PET, and precipitation data were compared to analyze the spatial and long-term (2001-2016) temporal distributions of average annual ET, PET, and precipitation, and to understand the relationships between them in the study region. The results showed that each selected zone had highest ET at the counties with the Yangtze River passing through whereas lowest at the counties which were located away from the river. Results also showed increasing trends in ET and PET from south-west to north-east in the study region. Analysis showed TGR had a significant impact on spatial and temporal distributions of ET and PET in the study region. Therefore, this study helps to understand the impact of TGR on spatial and temporal distributions of ET and PET during and after the construction. [ABSTRACT FROM AUTHOR]

The all-solid-state lithium batteries using solid electrolytes are considered to be the new generation of devices for energy storage, which might be a key solution for power electric and hybrid electric vehicles in the future. This review focuses on the crystal structures and electrochemical properties of sulfide solid electrolytes. They are classified to several subgroups according to their chemical compositions, namely thiophosphates, halide thiophosphates, sulfide without phosphorus, and glassy sulfides electrolytes, which might be potential solid electrolytes in lithium batteries and may replace the currently used polymeric electrolytes for LIBs. Through discussion, this review provides an insight into future promising sulfide electrolytes. [ABSTRACT FROM AUTHOR]

Ferrous sulfide (FeS) particles dispersed in the pores of carbon (FeS/PC) from the polyacrylonitrile carbonization were prepared via a facile one-pot solid-state method, which was extensively characterized by XRD, SEM, TEM, Raman spectrum, and XPS techniques. As an anode material for lithium-ion batteries, this FeS/PC composite can achieve a high initial discharge capacity of 1428.8 mAh/g at 0.1 C, and can maintain 624.9 mAh/g capacity after 150 cycles. The porous carbon accommodates the volume change during the cycling, and the special structure of the FeS/PC composite results in its advanced electrochemical performance by enhancing the structure stability. [ABSTRACT FROM AUTHOR]

The γ-LiFeO micro-cubes were synthesized using a simple solid-state method. Their electrochemical performance as anode material for lithium ion batteries was firstly investigated. Pure γ-LiFeO without nanosizing or carbon coating can deliver the first discharge capacity of 1055.3 mAh/g, and 611.5 mAh/g can be maintained after 50 cycles, around 80 % of the second discharge capacity. γ-LiFeO also demonstrates nice rate capabilities. These results indicate that γ-LiFeO is a promising anode material candidate for lithium ion batteries. The charge/discharge mechanism was also investigated. [ABSTRACT FROM AUTHOR]

The FeSSe particles dispersed in the pores of carbon (FeSSe/PC) were prepared using a simple one-pot solid-state method, which were then characterized by XRD, SEM, TEM, XPS, and Raman spectrum techniques. As the anode material for lithium-ion batteries, FeSSe/PC displays an initial discharge capacity as high as 699.5 mAh/g at 0.1 C, and 327.9 mAh/g can be maintained after 200 cycles, much enhanced than those of pure FeSSe. The small particles of FeSSe wrapped in carbon can effectively buffer the volume expansion during charging/discharging to improve the electrochemical performance. [ABSTRACT FROM AUTHOR]

Fibroblast growth factor 20 (FGF20) is a neurotrophic factor which enhances the survival of rat midbrain dopamine neurons. Genetic variation in FGF20 may influence the risk of occurrence and development in Parkinson's diseases (PD). Many studies have evaluated the association between FGF20 rs1721100 C/G polymorphism and the risk of sporadic PD; however, published data are still controversial. The aim of the present meta-analysis was to evaluate the association of FGF20 rs1721100 C/G polymorphism with susceptibility of PD. The summary odds ratio (OR) with its 95 % confidence interval (CI) was calculated to estimate the association. Five case-control studies with a total of 3,463 sporadic PD cases and 4,606 controls were finally included into this meta-analysis. Neither the basic allele frequencies nor the genotypic distributions of rs1721100 C/G within FGF20 were different between two groups when all studies were pooled into the meta-analysis. Subgroup analysis by ethnicity showed FGF20 rs1721100 C/G polymorphism was significantly associated with increased risk in the heterozygote comparison model (CG versus GG: OR = 0.83, 95 % CI, 0.72-0.95, P = 0.009) in Asians but not in Caucasians. Overall, this meta-analysis suggests that FGF20 rs1721100 C/G polymorphism is associated with sporadic PD in Asians. [ABSTRACT FROM AUTHOR]

The SU(VAR)3-9-like histone methyltransferases usually catalyze repressive histone H3K9 methylation and are involved in transcriptional gene silencing in eukaryotic organisms. We identified a putative SU(VAR)3-9-like histone methyltransferase SUVR2 by a forward genetic screen and demonstrated that it is involved in transcriptional gene silencing at genomic loci targeted by RNA-directed DNA methylation (RdDM). We found that SUVR2 has no histone methyltransferase activity and the conserved catalytic sites of SUVR2 are dispensable for the function of SUVR2 in transcriptional silencing. SUVR2 forms a complex with its close homolog SUVR1 and associate with three previously uncharacterized SNF2-related chromatin-remodeling proteins CHR19, CHR27, and CHR28. SUVR2 was previously thought to be a component in the RdDM pathway. We demonstrated that SUVR2 contributes to transcriptional gene silencing not only at a subset of RdDM target loci but also at many RdDM-independent target loci. Our study suggests that the involvement of SUVR2 in transcriptional gene silencing is related to nucleosome positioning mediated by its associated chromatin-remodeling proteins. [ABSTRACT FROM AUTHOR]

Spectral counting has become a widely used approach for measuring and comparing protein abundance in label-free shotgun proteomics. However, when analyzing complex samples, the ambiguity of matching between peptides and proteins greatly affects the assessment of peptide and protein inventories, differentiation, and quantification. Meanwhile, the configuration of database searching algorithms that assign peptides to MS/MS spectra may produce different results in comparative proteomic analysis. Here, we present three strategies to improve comparative proteomics through spectral counting. We show that comparing spectral counts for peptide groups rather than for protein groups forestalls problems introduced by shared peptides. We demonstrate the advantage and flexibility of this new method in two datasets. We present four models to combine four popular search engines that lead to significant gains in spectral counting differentiation. Among these models, we demonstrate a powerful vote counting model that scales well for multiple search engines. We also show that semi-tryptic searching outperforms tryptic searching for comparative proteomics. Overall, these techniques considerably improve protein differentiation on the basis of spectral count tables. [ABSTRACT FROM AUTHOR]

Compacts of FeO and FeO doped with varying amounts of NaO were isothermally reduced at several temperatures, using CO/CO mixed gas in a vertical resistance furnace. To determine the effect of NaO on the reduction of FeO compacts, the mass loss due to oxygen removal was continuously recorded, from which the reduction rate and rate constant were obtained. NaO was found to retard the reduction of FeO compacts. The apparent activation energy ( E) of reaction and the mathematical relationship for pore gas diffusion suggested that the reduction behavior at the initial stages was controlled by a combination of pore gas diffusion and interfacial chemical reaction. At the intermediate and late stages of reduction, pore gas diffusion was the sole contributing factor. Morphological examination of the reduced compacts showed the formation of a liquid phase during the reduction process, which appeared to lower the rate of reaction. [ABSTRACT FROM AUTHOR]

The article focuses on the chemical constituents of red algae Chondrophycus papillosus (C. papillosus) and their cytotoxic activity. It states that various compounds were isolated and identified from C. papillosus including aristolane sesquiterpenes, linear diterpene, and polybrominated indoles. Moreover,the metabolites such as aristolen-9β-ol, Tetrabomo-1-methyl-1H-indole, and Tetrabromoindole showed cytotoxity against tumor cell lines like chronic myelogenous leukemia cells (K562).

Copyright of Neuroscience Bulletin is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Is the radiomic approach, utilizing diffusion-weighted imaging (DWI), capable of predicting the various pathological grades of intrahepatic mass-forming cholangiocarcinoma (IMCC)? Furthermore, which model demonstrates superior performance among the diverse algorithms currently available? The objective of our study is to develop DWI radiomic models based on different machine learning algorithms and identify the optimal prediction model. We undertook a retrospective analysis of the DWI data of 77 patients with IMCC confirmed by pathological testing. Fifty-seven patients initially included in the study were randomly assigned to either the training set or the validation set in a ratio of 7:3. We established four different classifier models, namely random forest (RF), support vector machines (SVM), logistic regression (LR), and gradient boosting decision tree (GBDT), by manually contouring the region of interest and extracting prominent radiomic features. An external validation of the model was performed with the DWI data of 20 patients with IMCC who were subsequently included in the study. The area under the receiver operating curve (AUC), accuracy (ACC), precision (PRE), sensitivity (REC), and F1 score were used to evaluate the diagnostic performance of the model. Following the process of feature selection, a total of nine features were retained, with skewness being the most crucial radiomic feature demonstrating the highest diagnostic performance, followed by Gray Level Co-occurrence Matrix lmc1 (glcm-lmc1) and kurtosis, whose diagnostic performances were slightly inferior to skewness. Skewness and kurtosis showed a negative correlation with the pathological grading of IMCC, while glcm-lmc1 exhibited a positive correlation with the IMCC pathological grade. Compared with the other three models, the SVM radiomic model had the best diagnostic performance with an AUC of 0.957, an accuracy of 88.2%, a sensitivity of 85.7%, a precision of 85.7%, and an F1 score of 85.7% in the training set, as well as an AUC of 0.829, an accuracy of 76.5%, a sensitivity of 71.4%, a precision of 71.4%, and an F1 score of 71.4% in the external validation set. The DWI-based radiomic model proved to be efficacious in predicting the pathological grade of IMCC. The model with the SVM classifier algorithm had the best prediction efficiency and robustness. Consequently, this SVM-based model can be further explored as an option for a non-invasive preoperative prediction method in clinical practice., (© 2024. The Author(s) under exclusive licence to Society for Imaging Informatics in Medicine.)