A screened predictive model for esophageal squamous cell carcinoma based on salivary flora data

Esophageal squamous cell carcinoma (ESCC) is a malignant tumor of the digestive system in the esophageal squamous epithelium. Many studies have linked esophageal cancer (EC) to the imbalance of oral microecology. In this work, different machine learning (ML) models including Random Forest (RF), Gaussian mixture model (GMM), K-nearest neighbor (KNN), logistic regression (LR), support vector machine (SVM) and extreme gradient boosting (XGBoost) based on Genetic Algorithm (GA) optimization was developed to predict the relationship between salivary flora and ESCC by combining the relative abundance data of Bacteroides, Firmicutes, Proteobacteria, Fusobacteria and Actinobacteria in the saliva of patients with ESCC and healthy control. The results showed that the XGBoost model without parameter optimization performed best on the entire dataset for ESCC diagnosis by cross-validation (Accuracy = 73.50%). Accuracy and the other evaluation indicators, including Precision, Recall, F1-score and the area under curve (AUC) of the receiver operating characteristic (ROC), revealed XGBoost optimized by the GA (GA-XGBoost) achieved the best outcome on the testing set (Accuracy = 89.88%, Precision = 89.43%, Recall = 90.75%, F1-score = 90.09%, AUC = 0.97). The predictive ability of GA-XGBoost was validated in phylum-level salivary microbiota data from ESCC patients and controls in an external cohort. The results obtained in this validation (Accuracy = 70.60%, Precision = 46.00%, Recall = 90.55%, F1-score = 61.01%) illustrate the reliability of the predictive performance of the model. The feature importance rankings obtained by XGBoost indicate that Bacteroides and Actinobacteria are the two most important factors in predicting ESCC. Based on these results, GA-XGBoost can predict and diagnose ESCC according to the relative abundance of salivary flora, providing an effective tool for the non-invasive prediction of esophageal malignancies

Sustainable sandwich composites manufactured from recycled carbon fibers, flax fibers/PP skins, and recycled PET core

European union end of life vehicle directive mandates the use of more sustainable/recyclable materials in automotive industries. Thermoplastics matrix-based composites allow recyclability of composites at the end of life; however, their processing technology is more challenging than thermoset composites. Manufacturing process and mechanical testing of sustainable sandwich composite made from sustainable materials: flax, recycled carbon fiber, polypropylene, and recycled PET foam are presented in this article. High pressure compression molding with adhesive thermoplastic polymer film was used for manufacturing sandwich composite skin. The recycled PET foam core was integrated/joined with the skin using a thermoplastics adhesive film. A three-point bending test was conducted to compare the flexural properties. The results show that such sustainable sandwich composites will be an excellent material for truck side panel to operate in adverse wind/storm conditions. The sustainable sandwich composite can potentially be an excellent candidate for the fabrication of light-duty, lightweight, and low-cost engineering structures in automotive industry to meet the EU end of life requirements

Universal scaling of the critical temperature and the strange-metal scattering rate in unconventional superconductors

Dramatic evolution of properties with minute change in the doping level is a hallmark of the complex chemistry which governs cuprate superconductivity as manifested in the celebrated superconducting domes as well as quantum criticality taking place at precise compositions. The strange metal state, where the resistivity varies linearly with temperature, has emerged as a central feature in the normal state of cuprate superconductors. The ubiquity of this behavior signals an intimate link between the scattering mechanism and superconductivity. However, a clear quantitative picture of the correlation has been lacking. Here, we report observation of quantitative scaling laws between the superconducting transition temperature $T_{\rm c}$ and the scattering rate associated with the strange metal state in electron-doped cuprate $\rm La_{2-x}Ce_xCuO_4$ (LCCO) as a precise function of the doping level. High-resolution characterization of epitaxial composition-spread films, which encompass the entire overdoped range of LCCO has allowed us to systematically map its structural and transport properties with unprecedented accuracy and increment of $\Delta x = 0.0015$. We have uncovered the relations $T_{\rm c}\sim(x_{\rm c}-x)^{0.5}\sim(A_1^\square)^{0.5}$, where $x_c$ is the critical doping where superconductivity disappears on the overdoped side and $A_1^\square$ is the scattering rate of perfect $T$-linear resistivity per CuO$_2$ plane. We argue that the striking similarity of the $T_{\rm c}$ vs $A_1^\square$ relation among cuprates, iron-based and organic superconductors is an indication of a common mechanism of the strange metal behavior and unconventional superconductivity in these systems.Comment: 15 pages, 3 figure

A new well-posed algorithm to recover implied local volatility

This paper presents a new algorithm to calibrate the option pricing model, i.e. the algorithm that recovers the implied local volatility function from market option prices in the optimal control framework. A unique optimal control is shown to exist. Our algorithm is well-posed. Our numerical experiments show that, with the help of the techniques developed in the field of optimal control, the local volatility function is recovered very well.

Root Distribution and Root Cohesion of Two Herbaceous Plants in the Loess Plateau of China

In order to understand the root morphology distribution and mechanical properties of typical herbaceous plants, and to evaluate the ability of soil reinforcement by the plant roots, root morphology investigation, single root tensile test in laboratory and root cohesion evaluation by the Wu-Waldron model were carried out on two local representative herbaceous plants, Kochia scoparia (L.) Schrad and Artemisia sacrorum Ledeb. in the Loess Plateau of China. The results showed that the root morphological indexes (root number, single root diameter, root cross-sectional area, root surface area, root volume and root area ratio) of the two herbaceous plants decreased with the increase in soil depth, and the ratio of root to shallow soil layer was the highest in the 0–10 cm soil layer. The efficiency of root reinforcement could be higher in the shallow soil layer less than 10 cm. A positive correlation was observed between the root tensile force and root diameter in power function or exponential function, and a negative correlation was observed between the root tensile strength and root diameter in power function. The root cohesion of Kochia scoparia (2.73 kPa, or 0.92 kPa–1.37 kPa) was greater than that of Artemisia sacrorum (1.60 kPa, or 0.54 kPa–0.8 kPa), which could be used as the preferred herbaceous plant species for soil erosion control. The results could provide a scientific basis for selecting dominant species in the fields of ecological slope protection and soil and water conservation plant engineering in the loess area

State-specific modulation of mood using intracranial electrical stimulation of the orbitofrontal cortex

Background: Orbitofrontal cortex (OFC) is a promising target for intracranial electrical stimulation (iES) aimed at improving mood states. However, knowledge gaps remain regarding the underlying neural mechanisms of iES effects, such as the effect of the OFC target in comparison with other emotional network targets, the impact of brain state at the time of stimulation, and the neural response induced by iES at both local and network scales. Objective: Our study aims to address the neural mechanisms underlying the effects of iES in improving mood states. Methods: We conducted a study in 24 epilepsy patients who received iES through implanted electrodes in the emotional network and compared the effects of iES on multiple targets in the emotional network. Results: We found that only iES applied to the orbitofrontal cortex (OFC) led to mood improvement and changes in neural activity. We also observed that iES to the OFC suppressed the delta-theta power when the brain was in a low mood state. Moreover, the iES to the OFC decreased delta-theta power and increased gamma power at local regions within the emotional network, and enhanced the information flow through the frequency domain among regions within the emotional network. Conclusions: These findings provide insight into the neural correlates of iES-induced mood improvement and support the potential of iES as a therapeutic intervention for mood disorders

How Does Embedding Angle Affect Root–Soil Mechanical Interactions?

Root–soil mechanical interactions are of vital importance in soil reinforcement by plant roots. However, it is unclear how the angles of the roots in the soil affect the root–soil mechanical interactions. To better understand the effect of this factor on root–soil mechanical interactions, pullout tests were conducted on alfalfa (Medicago sativa L.) roots with five root diameter groups (0.10–0.30 mm, 0.31–0.50 mm, 0.51–0.70 mm, 0.71–0.90 mm and 0.91–1.10 mm) and four embedding angles (30°, 45°, 60° and 90°) in sandy loam soil. Root tensile tests were also carried out to understand the process of root failure in the pullout tests. The results showed that the roots had two failure modes, slippage failure and breakage failure. The critical diameter of the two failure modes was 0.35 mm. Peak pullout force and pullout energy were positively related to the root diameter in power functions. Displacement was negatively related to the root diameter and embedding angle in exponential functions. Peak pullout force, root–soil friction coefficient and pullout energy all increased and then decreased with increasing embedding angles. The peak pullout force and root–soil friction coefficient reached their maximum values under an embedding angle of 60°, and pullout energy reached the maximum value under an embedding angle of 45°. Pullout energy was suggested as a preferred index of root–soil mechanical interactions for both thick/fine roots and inclined/upright roots