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We aimed to develop a radiomics model to predict the histopathological grading of meningiomas by magnetic resonance imaging (MRI) before surgery. We recruited 131 patients with pathological diagnosis of meningiomas. All the patients had undergone MRI before surgery on a 3.0 T MRI scanner to obtain T1 fluid- attenuated inversion recovery (T1 FLAIR) images, T2-weighted images (T2WI) and T1 FLAIR with contrast enhancement (CE-T1 FLAIR) images covering the whole brain. The removing features with low variance, univariate feature selection, and least absolute shrinkage and selection operator (LASSO) were used to select radiomics features. Six classifiers were used to train the models (logistic regression (LR), k-nearest neighbor (KNN), decision tree (DT), support vector machine (SVM), random forests (RF), and XGBoost), and then 24 models were established using a random verification method to differentiate low-grade from high-grade meningiomas. The performance was assessed by receiver-operating characteristic (ROC) analysis, the f1-score, sensitivity, and specificity. The radiomics features were significantly associated with the histopathological grading. Quantitative imaging features (n = 1409) were extracted, and nine features were selected to predict the grades of meningiomas. The best performance of the radiomics model for the degree of differentiation was obtained by SVM (area under the curve (AUC), 0.956; 95% confidence interval (CI), 0.83–1.00; sensitivity, 0.87; specificity, 0.92; f1-score, 0.90). The radiomics models are of great value in predicting the histopathological grades of meningiomas, and have broad prospects in radiology and clinics. [ABSTRACT FROM AUTHOR]

Background: Arachidonic acid (AA) is the major polyunsaturated fatty acid (PUFA) substrate for potent eicosanoid signaling to modulate inflammation and thrombosis and is controlled in part by tissue abundance. Fatty acid desaturase 1 (FADS1) catalyzes synthesis of omega-6 (n-6) AA and n-3 eicosapentaenoic acid (EPA). The rs66698963 polymorphism, a 22-base pair (bp) insertion-deletion 137 bp downstream of a sterol regulatory element in FADS2 intron 1, mediates expression of FADS1 in vitro, as well as exerting positive selection in several human populations. The associations between the polymorphism rs66698963 and plasma PUFAs as well as disease phenotypes are unclear. Objective: This study aimed to evaluate the relation between rs66698963 genotypes and plasma PUFA concentrations and blood lipid profiles. Design: Plasma fatty acids were measured from a single sample obtained at baseline in 1504 healthy Chinese adults aged between 35 and 59 y with the use of gas chromatography. Blood lipids were measured at baseline and a second time at the 18-mo follow-up. The rs66698963 genotype was determined by using agarose gel electrophoresis. Linear regression and logistic regression analyses were performed to assess the association between genotype and plasma PUFAs and blood lipids. Results:Ashift from the precursors linoleic acid and α-linolenic acid to produce AA and EPA, respectively, was observed, consistent with FADS1 activity increasing in the order of genotypes D/D to I/D to I/I. For I/I comparedwith D/D carriers, plasma concentrations of n-6AA and the ratio of AA to n-3 EPA plus docosahexaenoic acid (DHA) were 57% and 32% higher, respectively. Carriers of the deletion (D) allele of rs66698963 tended to have higher triglycerides (β = 0.018; SE: 0.009; P = 0.05) and lower HDL cholesterol (β =-0.008; SE: 0.004; P = 0.02) than carriers of the insertion (I) allele. Conclusions: The rs66698963 genotype is significantly associated with AA concentrations and AA to EPA+DHA ratio, reflecting basal risk of inflammatory and related chronic disease phenotypes, and is correlated with the risk of dyslipidemia. This trial was registered at chictr.org.cn as ChiCTR-EOC-17012759. [ABSTRACT FROM AUTHOR]

Triterpenoids and flavonoids from licorice (Glycyrrhiza uralensis Fisch.) are known to have a wide range of applications in the pharmaceutical, skin care, and food industries. The effects of various types of abiotic stresses and associated phytohormones - polyethylene glycol, sodium chloride, ultraviolet, cadmium, abscisic acid, and methyl jasmonate - on both the content of these secondary metabolites and the transcript levels of genes encoding enzymes of important biosynthetic pathways were evaluated in hydroponic seedlings of G. uralensis. In these treatments, abscisic acid induced a substantial increase in the levels of the four active compounds, compared to the control. Analysis of the expression of genes involved in the biosynthetic pathways of these compounds, such as FPPS , showed that their transcript levels were significantly up-regulated in the four stresses. These findings suggested that the multi-stress superposition pattern of the content of active compounds and the gene expression of their biosynthetic pathways may provide insights to explore the management of secondary metabolite synthesis pathways in medicinal plants. It could facilitate a better understanding of the formation patterns of active compounds in licorice in artificial cultivation. Further insights may also be provided to increase the yield of these high value components. [Display omitted] • Exogenous abscisic acid has a positive effect on the active compounds of licorice. • Glycyrrhizic acid-related gene expression was uprated in PEG and UV treatments. • Hydroponic system can be used to study the effect of abiotic stresses on licorice. • Multi-stress has potential in regulation and production of secondary metabolites. [ABSTRACT FROM AUTHOR]

Drought stress triggers complex physiological and biochemical responses in plants. Different plant species have also evolved several morphological, physiological, biochemical, cellular, and molecular mechanisms to overcome drought stress conditions. However, genotype-specific response factors associated with drought tolerance and the balanced relationship between active components and stress conditions are still not fully elucidated. Licorice (Glycyrrhiza Tourn. L.) is a perennial herb of the Leguminosae family which is widely used as a spice in the food industry. It is favored for its sweet and distinctive aromatic flavor, which is attributed to its glycyrrhizic acid, liquiritin, and other components. The influence of drought stress on different species of licorice was analyzed. Seed germination parameters, the activity of anti-oxidative enzymes, osmoregulation, and active compound contents were compared in three licorice species (Glycyrrhiza glabra L., Glycyrrhiza uralensis Fisch., and Glycyrrhiza inflata Bat.). The results indicated a level of drought stress that balanced relatively good growth trends and high expression of active compounds in individual licorice species. With increasing drought stress, G. uralensis and G. glabra had lower values of early germination indicators (germination energy, germination rate, and germination index), when compared to G. inflata. The highest values of antioxidant enzyme activity and active compound content were detected at lower stress levels in both G. uralensis and G. glabra. The active components (glycyrrhizic acid, liquiritin, isoliquiritin, liquiritigenin, isoliquiritigenin, 4′,7-dihydroxyflavone, and licochalcone A) showed significantly different trends in different species under drought stress. The current study will help understand the effects of drought stress on licorice plants. The results highlight the importance of preserving regional genetic diversity for adaptive evolution in response to global climate change. It also provides a theoretical basis for revealing rational cropping regions and formulating adaptive irrigation strategies. [Display omitted] • Three licorice genotypes show differential germination response to drought stress. • Enzyme activity in licorice seedlings was significantly influenced by genotypes. • Proline content was not influenced by genotypes. • Contents of active components differed significantly among genotypes under drought. [ABSTRACT FROM AUTHOR]

MXene (Ti 3 C 2 T x) is an important category of two-dimensional (2D) materials due to its distinctive metallic conductivity and adjustable surface chemistry. The exceptional benefits of heterointerface and defects or viods, combined with the distinct electromagnetic (EM) properties, inject boundless potential into the advancement of MXene-based absorbers for EM absorbing materials. However, conventional synthetic methods depend on chemical etching of MAX powders (Ti 3 AlC 2) using hazardous HF or similar substances, resulting in MXene sheets with fluorine termination and limited stability in colloidal dispersions under ambient conditions. Herein, varied synthetic routes were proposed to prepare MXenes with different terminal groups by the fluoride-based salts, fluoride-free molten salts, and alkali etching. 2D MXene nanosheets with abundant surface groups are excellent EM absorbing materials, and the MXene etched by the Lewis acid CuCl 2 delivered remarkable reflection loss (RL) value of −47.56 dB at 2.5 mm and broad bandwidth of 4.8 GHz due to promoted interfacial polarization. By conducting a thorough examination of the structural changes in MXenes, this study aims to propose a viable method for delaminating single-layer MXene and elucidate the EM absorption mechanisms. [Display omitted] [ABSTRACT FROM AUTHOR]

The current investigation deals with the nonlinear oscillation response of conical microshells made of a composite material with functional graded (FG) in-plane heterogeneity is studied in the presence of the size dependency. To accomplish this purpose, various types of homogenization schemes including Voigt model, Reuss model, Mori-Tanaka model, and Hashin-Shtrikman bounds model are employed. The size-dependent characteristics are taken into consideration on the basis of the modified couple stress theory of elasticity within the framework of the higher-order shear deformation shell theory. The couple stress-based differential equations of motion are constructed via the Hamilton's principle. An efficient numerical solution methodology adopting generalized differential quadrature (GDQ) method together with the pseudo-arc technique is put to use to obtain the modified couple stress-based nonlinear frequency of homogenized FG composite conical microshells. It is demonstrated that by increasing the value of the maximum shell deflection, the couple stress type of size effect plays more important role in the nonlinear vibration response of FG composite conical microshells. Additionally, it is indicated by changing the boundary conditions from simply supported one to clamped one, the influence of couple stress size dependency decreases. • Development a modified couple stress-based conical shell model. • Modeling FGM conical micro/nano-shells based on different homogenization schemes. • Obtain the modified couple stress-based nonlinear frequency of FGM conical micro/nano-shells. • Study the influences of boundary conditions and geometrical parameters on the size-dependent nonlinear vibration response. [ABSTRACT FROM AUTHOR]

• The failure mode and deformation characteristics of segmented utility tunnel are analyzed. • The relationship between the failure mode and intersection angles is analyzed. • The deformation of utility tunnel is calculated based on the holding effect of stratum. Ground fissures are a special urban geological disaster within the city of Xi'an. The differential settlement between strata can cause ground cracking and severely threatens the safe construction and operation of underground engineering. This study establishes a 3D-FDM calculation model of different intersection relationships between the segmented utility tunnel and the ground fissures using Flac 3D software. The influence of the intersection angles on the deformation and failure characteristics of the structure was analyzed. The results show that the segmented utility tunnel presents with the deformation characteristic of three-dimensional movement under the action of the ground fissures. The deformation between structures is primarily vertical dislocation, horizontal tension, and compression, indicating that the structure may be subjected to a bending-torsion failure. The vertical settlement of the roof of the utility tunnel shows the deformation characteristics of three broken lines. The third and fourth structures have a significant differential settlement, showing a negative correlation with the intersection angle. The segmented measures can eliminate the void area at the bottom of the hanging wall in the utility tunnel; however, when the intersection angle is ≤30°, the contact pressure at the bottom is close to 0, indicating that the intersection angle has a significant impact on the formation of the void areas. In addition, the calculation method of the vertical settlement of the segmented utility tunnel crossing the ground fissure zone is also proposed. It has proven to be effective in calculating the vertical deformation of the structure. This study provides scientific guidance for constructing utility tunnels within ground fissure development areas. [ABSTRACT FROM AUTHOR]

• First and repeated cat and rabbit odor exposure decreased hovering over pups in postpartum voles. • First and repeated cat odor exposure decreased pup retrieval in postpartum voles. • First and repeated rabbit odor exposure affected pup licking in parturient voles. • Repeated cat odor exposure during postpartum period enhanced offspring's locomotor activity. Recent evidence indicates that predation risk plays a special role in the rodent behavior of dams and offspring, but little is known about the effect of maternal exposure to the predator cues in the absence of pups. Here, we assessed the effects of repeated predator odor exposure on various maternal responses in postpartum Brandt's voles (Lasiopodomys brandtii). We also examined offspring's behavioral response to a novel environment. Only mother voles were exposed to distilled water, rabbit urine and cat urine for 60 min daily from postpartum day (PP) 1–18. Maternal behavior was immediately tested after these exposures on PP1, 3, 6, 9 and 18. Repeated cat odor (CO) and rabbit odor (RO) exposure disrupted hovering over pups in a time-dependent fashion. Repeated CO exposure also time-dependently disrupted pup retrieval, whereas RO exposure induced long-term reduction in pup licking. Juvenile offspring of CO-exposed mothers showed increased locomotor activity and decreased rearing in the open field at postnatal day 30. These findings demonstrated that maternal exposure to predator or non-predator odors had a disruptive effect on the maternal behavior of Brandt's voles when only the mother was exposed to these odors, and that the adversity experience with predation risk significantly impacted the behavioral development of offspring. Future work should explore possible behavioral mechanisms, such as the effect of predation risk, on the dams' emotional processing or pup preference. [ABSTRACT FROM AUTHOR]