Enhancing Thermal Conductivity of hBN/SiC/PTFE Composites with Low Dielectric Properties via Pulse Vibration Molding.

In order to enhance the thermal conductivity of polytetrafluoroethylene (PTFE)-based composites, while maintaining relatively low dielectric constant and dielectric loss for high-frequency and high-speed applications, hexagonal boron nitride (hBN) and silicon carbide (SiC) compounded fillers are filled into the PTFE matrix. The hBN/SiC/PTFE composites are prepared by pulse vibration molding (PVM), and their subsequent thermal conductivities are comparatively investigated. The PVM process with controlled fluctuation in pressure (1 Hz square wave force, 0-20 MPa, at 150 °C) can reduce the sample porosity and surface defects, improve the orientation of hBN, and increase the thermal conductivity by 44.6% compared with that obtained by compression molding. When hBN:SiC (vol) is 3:1, the in-plane thermal conductivity of the composite with 40 vol% filler content is ≈4.83 W m-1  K-1 , which is 40.3% higher than that of hBN/PTFE. Regarding the dielectric properties, hBN/SiC/PTFE maintains a low dielectric constant of 3.27 and a low dielectric loss of 0.0058. The dielectric constants of hBN/SiC/PTFE ternary composites are predicted by using different prediction models, among which the effective medium theory (EMT), is in good agreement with the experimental results. PVM shows great potential in the large-scale preparation of thermal conductive composites for high-frequency and high-speed applications.

Low-Temperature Potassium Batteries Enabled by Electric and Thermal Field Regulation.

Recharging batteries operate at sub-zero temperature is usually limited by the slow ion diffusion and uneven charge distribution at low temperature. Here, we report a strategy to regulate electric field and thermal field simultaneously, creating a fast and uniform deposition surroundings for potassium ion in potassium metal batteries (PMBs). This regulation is achieved by using a highly ordered 1D nanoarray electrode which provides a dense and flat surface for uniforming the electric field and high thermal conductivity for reducing the temperature fluctuation. Consequently, this electrode could achieve high-areal capacity of 10 mAh cm-2 . Besides, the dependence of potassium nucleation on temperature is unveiled. Furthermore, a full-cell could steady operate with over 80 % of its room-temperature capacity at -20 °C. Those respectable performances demonstrate that this strategy is valid, potentially providing guidelines for the rational design of advanced electrodes toward PMBs.

Overexpression of miR-138-5p Sensitizes Taxol-Resistant Epithelial Ovarian Cancer Cells through Targeting Cyclin-Dependent Kinase 6.

BACKGROUND: Ovarian cancer, one of the most malignant diseases in female, is associated with poor diagnosis and low 5-year survival rate. Taxol is a widely used chemotherapeutic drug for the treatment of ovarian cancer by targeting the microtubules of the mitotic spindle to induce cancer cell death. However, with the widespread clinical applications of Taxol, a large fraction of ovarian cancer patients developed drug resistance. RESULTS: Here, we report miR-138-5p is significantly downregulated in epithelial ovarian cancer tissues compared with their matched normal ovarian tissues. Overexpression of miR-138-5p effectively sensitized ovarian cancer cells to Taxol. By establishing Taxol-resistant cell line from the epithelial ovarian cancer cell line, HO-8910, we found miR-138-5p was significantly downregulated in Taxol-resistant cells. Furthermore, overexpression of miR-138-5p dramatically overcame the chemoresistance of Taxol-resistant cells. Intriguingly, bioinformatic analysis indicated miR-138-5p had putative binding sites for cyclin-dependent kinase 6 (CDK6). This negative regulation was further verified from epithelial ovarian cancer tissues. Luciferase assay demonstrated miR-138-5p could directly bind to 3'UTR of CDK6. Importantly, silencing CDK6 expression by siRNA successfully increased the sensitivity of both parental and Taxol-resistant ovarian cancer cells. Finally, rescue experiments clearly elucidated restoration of CDK6 in miR-138-5p-overexpressing ovarian cancer cells successfully recovered the Taxol resistance. CONCLUSION: In summary, these findings suggest important molecular mechanisms for the miR-138-5p-mediated Taxol sensitivity of ovarian cancer via directly targeting CDK6, suggesting miR-138-5p is an effective therapeutic target for the noncoding RNA-based anti-chemoresistance treatment.

Interaction between obstructive sleep apnea and short sleep duration on insulin resistance: a large-scale study : OSA, short sleep duration and insulin resistance.

OBJECTIVES: Both short sleep duration and obstructive sleep apnea (OSA) seem to be associated with insulin resistance. We aimed to explore whether short sleep duration modifies the relationship between OSA and insulin resistance. METHODS: Participants were consecutively enrolled from our sleep center during the period from 2007 to 2017. The index of homeostasis model assessment insulin resistance (HOMA-IR) was calculated from insulin and glucose. Sleep duration was determined by standard polysomnography. The associations between sleep duration and insulin resistance were estimated by logistic regression analyses. RESULTS: A total of 5447 participants (4507 OSA and 940 primary snorers) were included in the study. OSA was independently correlated with insulin resistance after adjusting for all potential confounders (OR, 1.319; 95% CI, 1.088-1.599), but not short sleep duration. In stratified analysis by sleep duration, compared with primary snorers, in the OSA group only extremely short sleep duration (< 5 h) was significantly associated with insulin resistance after adjusting for all covariates (OR, 2.229; 95% CI, 1.283-3.874). Rapid eye movement predominant OSA was significantly associated with insulin resistance (OR = 1.355, 95% CI: 1.019-1.802) after adjustment for confounding factors including age, sex and body mass index. CONCLUSIONS: OSA, but not short sleep duration, was independently associated with insulin resistance. It is worth noting that OSA combined with extremely short sleep duration showed a greater detrimental effect than OSA itself with regard to insulin resistance.

[Evaluating the risk of ischemic cerebral vascular disease with ocular hemodynamics in carotid artery stenosis patients].

OBJECTIVE: To evaluate the association between the ocular hemodynamic and the incidence of ischemic cerebral vascular diseases in carotid artery stenosis patients. METHODS: Case-control study. Seventy-two cases patients with carotid artery stenosis including 22 cases of cerebral infarction group, 14 cases of lacunar cerebral infarction group and the control group of the other 36 patients without cerebral infarction were recruited. All patients were measured with hemodynamic parameters of the ophthalmic artery, central retinal artery and posterior ciliary artery. PSV, EDV, PI and RI were also measured. The other risk ischemic cerebral vascular factors were obtained through the questionnaire and venous blood sampling. The differences of 3 groups and the influences of the other risk factor of hemodynamic were calculated. RESULTS: PSV of ophthalmic artery was (25.96 ± 12.63)cm/s in cerebral infarction group, (32.63 ± 13.25) cm/s in lacunar infarction group and (39.46 ± 14.97) cm/s in control group. EDV of ophthalmic artery was(6.09 ± 3.10) cm/s in cerebral infarction group, (6.57 ± 2.85) cm/s in lacunar infarction group and (9.73 ± 5.02) cm/s in control group. PSV of central retinal artery was (8.06 ± 2.98) cm/s in cerebral infarction group, (8.91 ± 2.76) cm/s in lacunar infarction group and (9.71 ± 2.60) cm/s in control group. The differences were statistically significant (F = 13.393, 12.609, 5.027, P < 0.01). EDV of central retinal artery was (2.46 ± 0.77) cm/s in cerebral infarction group, (2.35 ± 0.89) cm/s in lacunar infarction group and (2.73 ± 0.86) cm/s in control group. There was no statistical difference of EDV of CRA in three group (F = 2.405, P = 0.094). CONCLUSIONS: There was association between the ocular hemodynamic parameters and the incidence of ischemic cerebrovascular disease in the carotid artery stenosis patients. Increased level of PSV and EDV of the ophthalmic artery raised the risk of the incidence of ischemic cerebrovascular disease.

Preparation and properties of thermoplastic starch under the synergism of ultrasonic and elongational rheology.

Thermoplastic starch, as an eco-friendly alternative to petroleum-based plastics, possesses numerous advantages, including cost-effectiveness, complete biodegradability, and renewable sourcing. Nevertheless, the plasticizer dispersion and starch plasticization efficiency are poor via the processing method dominate by shear deformation. Thus, the aim of this study is proposing a new approach combining ultrasonic treatment and elongational rheology to prepare thermoplastic starch and evaluate its properties. This innovative approach facilitated the production of thermoplastic starch with glycerol as the plasticizer at varying rotor speeds. Furthermore, this study was carried out by using a self-developed ultrasonic-assisted vane mixer (UVM) based on elongational flow. The samples were analyzed using FTIR, WAXD, polarized optical microscope, dynamic rheometer, universal testing machine and thermogravimetric analysis. FTIR and dynamic rheological analysis showed that elongational rheology and ultrasonics stimulate hydrogen bond formation between starch and glycerol, elevating starch thermoplasticity. Tensile tests and thermogravimetric analysis highlighted that high-intensity elongational field improved the mechanical properties and thermal stability of the thermoplastic starch. Additionally, the incorporation of ultrasonic treatment yielded further improvements, yielding remarkable tensile strength (6.09 MPa) and elongation at break (139.3 %). This synergistic interplay between ultrasonics and elongational rheology holds immense potential for advancing thermoplastic starch manufacturing.

Separation of lignin derivatives from hemp fiber using supercritical CO2, ethanol, and water at different temperatures.

The process of lignin extraction often involves intricate chemical transformations, influencing its potential for high-value utilization. By investigating the process of lignin derivatives extraction from hemp fibers using supercritical CO2, ethanol, and water, we identified the relationship between the chemical structure of lignin derivatives and temperature. This discovery contributes to controlling the chemical structure of lignin derivatives through temperature modulation. We observed that lignin derivatives extracted within the temperature range of 100-120 °C exhibited the lowest average molecular weight and polydispersity index, presenting a disordered microstructure with the highest hydroxyl content. Lignin derivatives extracted between 140 and 160 °C showed an increase in average molecular weight and polydispersity index, decreased hydroxyl content, and a gradual transformation of microstructure into spherical particles. At 180 °C, the average molecular weight and polydispersity index of lignin derivatives decreased, the microstructure of lignin derivatives showed fewer spherical particles, while its hydroxyl content exhibited a partial recovery. Chemical analysis revealed a lower degree of condensation in lignin derivatives at 100-120 °C. Between 120 and 160 °C, the degree of condensation increased. At 180 °C, extensive degradation occurred in lignin derivatives. This research advances innovative techniques for lignin derivative separation, contributing to their utilization in higher-value applications.

Comprehensive assessment of health and ecological risk of cadmium in agricultural soils across China: A tiered framework.

Soil cadmium (Cd) contamination has been increasingly serious in agricultural land across China, posing unexpected risks to human health concerning crop safety and terrestrial ecosystems. This study collected Cd concentration data from 3388 soil sites in agricultural regions. To assess the Cd risk to crop safety, a comprehensive sampling investigation was performed to develop reliable Soil Plant Transfer (SPT) model. Eco-toxicity tests with representative soils and organism was conducted to construct the Species Sensitivity Distribution (SSD) for ecological risk assessment. Then, a tiered framework was applied based on Accumulation index, deterministic method (Hazard quotient), and probabilistic assessment (Monte Carlo and Joint Probability Curve). The results revealed the widespread Cd enrichment in agricultural soils, mainly concentrated in Central, Southern, and Southwest China. Risk assessments demonstrated the greater risks related to crop safety, while the ecological risks posed by soil Cd were manageable. Notably, agricultural soils in southern regions of China exhibited more severe risks to both crop safety and soil ecosystem, compared to other agricultural regions. Furthermore, tiered methodology proposed here, can be adapted to other trace elements with potential risks to crop safety and terrestrial ecosystem.

Brain white matter microstructural alterations in patients with systemic lupus erythematosus: an automated fiber quantification study.

This study aimed to identify damaged segments of brain white matter fiber tracts in patients with systemic lupus erythematosus (SLE) using diffusion tensor imaging (DTI)-based automated fiber quantification (AFQ), and analyze their relationship with cognitive impairment. Clinical and imaging data for 39 female patients with SLE and for 44 female healthy controls (HCs) were collected. AFQ was used to track whole-brain white matter tracts in each participant, and each tract was segmented into 100 equally spaced nodes. DTI metrics including fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were calculated at each node. Correlations were also explored between DTI metrics in the damaged segments of white matter fiber tracts and neuropsychological test scores of patients with SLE. Compared with HCs, SLE patients exhibited significantly lower FA values, and significantly higher MD, AD, RD values in many white matter tracts (all P < 0.05, false discovery rate-corrected). FA values in nodes 97-100 of the left inferior fronto-occipital fasciculus (IFOF) positively correlated with the mini-mental state examination score. AFQ enables precise and accurate identification of damage to white matter fiber tracts in brains of patients with SLE. FA values in the left IFOF correlate with cognitive impairment in SLE.

Heterogeneity and spillover effects of carbon emission trading on green innovation.

The massive emission of greenhouse gases poses a serious threat to the ecological environment. In this context, the relevant effects of the carbon emission trading (CET) market, which promotes greenhouse gas emission reduction by market means, have been widely investigated. Taking the China's CET pilot as a research target, the heterogeneity and spillover effects of CET on green innovation are explored by using the sample data of 279 prefecture-level cities in China from 2008 to 2019. The results are as follows. First, on the whole, CET significantly promotes strategic green innovation, but it has no significant effect on substantive green innovation. Second, the green innovation effect of CET varies with the level of green innovation, and the heterogeneous effects of green innovation are also reflected in different degrees of marketization, fiscal decentralization and government environmental concern. Third, CET has a positive spillover effect on green innovation, and the spillover effect is more significant than the direct effect, accounting for 74.8% of the total effect. Finally, some corresponding policy suggestions are put forward according to the above research conclusions.

Selective Potassium Deposition Enables Dendrite-Resistant Anodes for Ultrastable Potassium-Metal Batteries.

Instability at the solid electrolyte interface (SEI) and uncontrollable growth of potassium dendrites have been pressing issues for potassium-ion batteries. Herein, a self-supporting electrode composed of bismuth and nitrogen-doped reduced graphene oxide (Bi80 /NrGO) is designed as an anode host for potassium-metal batteries. Following the molten potassium diffusion into Bi80 /NrGO, the resulting K@Bi80 /NrGO exhibits unique hollow pores that provide K+ -diffusion channels and deposition space to buffer volume expansion, thus maintaining the electrode structure and SEI stability. The K@Bi80 /NrGO also provides a controlled electric field that promotes uniform K+ flux, abundant potassiophilic N sites, and Bi alloying active sites, collectively enabling precise nucleation and selective deposition of potassium to achieve dendrite-resistant anodes. With the K@Bi80 /NrGO-based optimized electrodes, the assembled K@Bi80 /NrGO symmetrical cells can sustain stable cycling over 3000 h at a current density of 0.2 mA cm-2 . Full cells with a Prussian blue cathode and K@Bi80 /NrGO anode exhibit high stability (with no degradation for 1960 cycles at 1000 mA g-1 ) with 99% Coulombic efficiency. This work may lead to the design of anodes with the triple attributes of precise nucleation, smooth diffusion, and dendrite inhibition, ideal for developing stable potassium-metal anodes and beyond.

Superstable potassium metal batteries with a controllable internal electric field.

Stable potassium metal batteries (PMBs) are promising candidates for electrical energy storage due to their ability to reversibly store electrical energy at a low cost. However, dendritic growth and large volume changes hinder their practical application. Here, referring to the morphology and structure of a virus, a bionic virus-like-carbon microsphere (BVC) was designed as the anode host for a PMB. A BVC with a three-dimensional structure can not only control the electric field, which can suppress dendrite formation, but can also provide a larger space to accommodate the volume change during the cycle progress. The designed potassium (K) metal anode exhibits excellent cycle life and stability (during 1800 h of repeated plating/stripping of K at a current density of 0.1 mA cm-2, K-BVC can realize a very stable K metal anode with low voltage hysteresis). Stable cyclability and improved rate capability can be realized in a full cell using Prussian blue over 400 cycles. This research provides a new idea for the development of stable K metal anodes and may pave the way for the practical application of next-generation metal batteries.

Construction of 3-Oxazolin-5-one via Visible Light-Induced Nondecarboxylative Coupling and Sequential Reactions.

3-Oxazolin-5-ones are precursors of nitrile ylides and represent valuable 1,3-dipoles for constructing cyclic imines or pyrrole compounds. Harnessing the power of photocatalysis, we accomplished a straightforward synthesis of 3-oxazolin-5-ones from redox-active esters and secondary nitro compounds. Visible light-induced nondecarboxylative coupling of a redox-active ester, nitro aldol condensation, and subsequent visible light-induced N-oxide deoxygenation were accomplished within 2 h. The reaction mechanism was supported by experimental data and DFT calculations.

Quasi-Solid Aqueous Electrolytes for Low-Cost Sustainable Alkali-Metal Batteries.

Aqueous electrolytes are highly important for batteries due to their sustainability, greenness, and low cost. However, the free water molecules react violently with alkali metals, rendering the high-capacity of alkali-metal anodes unusable. Here, water molecules are confined in a carcerand-like network to build quasi-solid aqueous electrolytes (QAEs) with reduced water molecules' freedom and matched with the low-cost chloride salts. The formed QAEs possess substantially different properties than liquid water molecules, including stable operation with alkali-metal anodes without gas evolution. Specifically, the alkali-metal anodes can directly cycle in a water-based environment with suppressed growth of dendrites, electrode dissolution, and polysulfide shuttle. Li-metal symmetric cells achieved long-term cycling over 7000 h (and over 5000/4000 h for Na/K symmetric cells), and all the Cu-based alkali-metal cells exhibited a Coulombic efficiency of over 99%. Full metal batteries, such as Li||S batteries, attained high Coulombic efficiency, long life (over 4000 cycles), and unprecedented energy density among water-based rechargeable batteries.

Water evaporation induced in-situ interfacial compatibilization for all-natural and high-strength straw-fiber/starch composites.

In this paper, we proposed a novel and green strategy based on water evaporation induced in-situ interfacial compatibilization (WEIC) mechanism for fabricating high-strength and all-natural lignocellulose/starch composites. This mechanism exploits the natural compatibility of the lignocellulose and starch and was tested through an internal mixing process with regulated water evaporation. Specifically, we revealed that a restrained layer was in-situ formed at the interface of the lignocellulose and starch during the internal mixing process; a faster water evaporation rate thickens this restrained layer, restricts the starch's molecular movement and significantly increases the composite's mechanical properties. The highest tensile strength and Young's modulus of the composites achieved are 21.7 ± 0.8 MPa and 2.2 ± 0.1 GPa, respectively, superior to many existing starch/lignocellulose composites. Thus, this work provides new insight into the compatibilization of various hydrophilic polysaccharides and paves new avenues for developing greener and more facile methods to fabricate all-polysaccharide composites.

Co-activation for enhanced K-ion storage in battery anodes.

The relative natural abundance of potassium and potentially high energy density has established potassium-ion batteries as a promising technology for future large-scale global energy storage. However, the anodes' low capacity and high discharge platform lead to low energy density, which impedes their rapid development. Herein, we present a possible co-activation mechanism between bismuth (Bi) and tin (Sn) that enhances K-ion storage in battery anodes. The co-activated Bi-Sn anode delivered a high capacity of 634 mAh g-1, with a discharge plateau as low as 0.35 V, and operated continuously for 500 cycles at a current density of 50 mA g-1, with a high Coulombic efficiency of 99.2%. This possible co-activation strategy for high potassium storage may be extended to other Na/Zn/Ca/Mg/Al ion battery technologies, thus providing insights into how to improve their energy storage ability.

Synthesis of ß-nitro ketones from geminal bromonitroalkanes and silyl enol ethers by visible light photoredox catalysis.

Various ß-nitro ketones, including those bearing a ß-tertiary carbon, were prepared from geminal bromonitroalkanes and trimethylsilyl enol ethers of a broad range of ketones by visible light photoredox catalysis, which were then easily converted into ß-amino ketones, 1,3-amino alcohols, α,ß-unsaturated ketones, ß-cyano ketones and γ-nitro ketones.

Derivation of Soil Criteria of Cadmium for Safe Rice Production Applying Soil-Plant Transfer Model and Species Sensitivity Distribution.

Widespread soil contamination is hazardous to agricultural products, posing harmful effects on human health through the food chain. In China, Cadmium (Cd) is the primary contaminant in soils and easily accumulates in rice, the main food for the Chinese population. Therefore, it is essential to derive soil criteria to safeguard rice products by assessing Cd intake risk through the soil-grain-human pathway. Based on a 2-year field investigation, a total of 328 soil-rice grain paired samples were collected in China, covering a wide variation in soil Cd concentrations and physicochemical properties. Two probabilistic methods used to derive soil criteria are soil-plant transfer models (SPT), with predictive intervals, and species sensitivity distribution (SSD), composed of soil type-specific bioconcentration factor (BCF, Cd concentration ratio in rice grain to soil). The soil criteria were back-calculated from the Chinese food quality standard. The results suggested that field data with a proper Cd concentration gradient could increase the model accuracy in the soil-plant transfer system. The derived soil criteria based on soil pH were 0.06-0.11, 0.33-0.59, and 1.51-2.82 mg kg-1 for protecting 95%, 50% and 5% of the rice safety, respectively. The soil criteria with soil pH further validated the soil as being safe for rice grains.

ß-Cell function and body mass index are predictors of exercise response in elderly patients with prediabetes.

AIMS/INTRODUCTION: To explore the predicting factors of exercise response (whether the participants converted to diabetes) in elderly patients with prediabetes. MATERIALS AND METHODS: This is a retrospective subgroup analysis of the registered clinical trial with previous publication of the same cohort. A total of 248 participants with prediabetes were randomized to the aerobic training (n = 83) group, resistance training (n = 82) group and control group (n = 83). The patients who finished the 2-year exercise intervention were included in this analysis to explore the factors impacting exercise response. RESULTS: A total of 113 patients with prediabetes completed 2 years of exercise, with 56 participants in the aerobic exercise group and 57 in the resistance exercise group. Patients who reversed to normal glucose tolerance, remained in prediabetes and developed diabetes were 18 (15.90%), 70 (62.00%) and 25 (22.10%), respectively. Logistic regression showed that baseline, homeostatic model 2 assessment of ß-cell function (ß = -0.143, P = 0.039), hemoglobin A1c (ß = 3.301, P = 0.007) and body mass index (ß = 0.402, P = 0.012) were related to exercise response, whereas the waist-to-hip ratio (ß = -3.277, P = 0.693) and types of exercise (ß = 1.192, P = 0.093) were not significantly related to exercise response. CONCLUSIONS: Baseline homeostatic model 2 assessment of ß-cell function, hemoglobin A1c and body mass index were the predictors for the response to exercise in elderly patients with prediabetes.

[Correlation between conventional ultrasound features and BRAFV600E gene mutation and central lymph node metastasis in thyroid papillary carcinoma].

Objective:To investigate whether central lymph node metastasis（CLNM） in the central region of thyroid papillary carcinoma（PTC） is related to conventional ultrasound features of the primary lesion and BRAFV600E gene mutation. Methods:A total of 300 patients with PTC confirmed by surgical pathology and central lymph node dissection in the First Affiliated Hospital of Jinzhou Medical University from October 2019 to June 2021 were collected. The subjects were divided into the metastatic group and the non-metastatic group according to whether CLNM occurred. The correlation was determined by analyzing the conventional ultrasound characteristics and BRAFV600E gene test results of the two groups of patients. Results:Among 300 PTC patients, 120（40%） had CLNM. Univariate analysis showed that there were statistically significant differences between groups in gender, nodule maximum diameter line, number of lesions, boundaries, morphology, aspect ratio, proximity to the membrane, calcification and BRAFV600E gene mutation（P<0.05）. Logistic multivariate regression analysis showed that gender, maximum diameter line, aspect ratio, proximity to the membrane, microcalcification and BRAFV600E were the risk factors for CLNM in PTC patients（P<0.05）. ROC curve showed that when the maximum diameter was 8.5 mm, the Yooden index was the maximum. Conclusion:When the risk factors of male, maximum diameter ≥8.5 mm, aspect ratio ≥1, microcalcification, proximity to capsule and BRAFV600E（+） appear in PTC patients, high attention should be paid to preventive CLN dissection as soon as possible.