Electric Field Effects in Flash Joule Heating Synthesis.

Flash Joule heating has emerged as an ultrafast, scalable, and versatile synthesis method for nanomaterials, such as graphene. Here, we experimentally and theoretically deconvolute the contributions of thermal and electrical processes to the synthesis of graphene by flash Joule heating. While traditional methods of graphene synthesis involve purely chemical or thermal driving forces, our results show that the presence of charge and the resulting electric field in a graphene precursor catalyze the formation of graphene. Furthermore, modulation of the current or the pulse width affords the ability to control the three-step phase transition of the material from amorphous carbon to turbostratic graphene and finally to ordered (AB and ABC-stacked) graphene and graphite. Finally, density functional theory simulations reveal that the presence of a charge- and current-induced electric field inside the graphene precursor facilitates phase transition by lowering the activation energy of the reaction. These results demonstrate that the passage of electrical current through a solid sample can directly drive nanocrystal nucleation in flash Joule heating, an insight that may inform future Joule heating or other electrical synthesis strategies.

Preoperative Serum Thyroglobulin Levels Predict Radioiodine Therapy Outcome in Papillary Thyroid Microcarcinoma Patients.

Our previous study showed that elevated preoperative thyroglobulin (pre-Tg) level predicted the risk of developing radioiodine refractory in PTC patients. In the present study, we aimed to evaluate the prognostic value of pre-Tg in papillary thyroid microcarcinoma (PTMC). After a specific inclusion and exclusion criteria were applied, a total of 788 PTMCs were enrolled from Jiangyuan Hospital affiliated to Jiangsu Institute of Nuclear Medicine between Jan 2015 and Dec 2019. Among them, 107 PTMCs were treated with radioiodine therapy (RAIT) and the response to therapy was grouped as excellent response (ER), and non-excellent response (NER: indeterminate response, IDR and biochemical incomplete response, BIR). Multivariable logistic regression was used to identify predictors for the response of RAIT in PTMCs. Higher pre-Tg levels were detected in PTMCs with RAIT as compared with PTMCs without RAIT (p=0.0018). Higher levels of pre-Tg were also found in patients with repeated RAIT as compared with patients with single RAIT (p<0.0001). Furthermore, pre-Tg level was higher in PTMC with IDR (n=16) and much higher in BIR (n=9) as compared with patients with ER (n=82, p=0.0003) after RAIT. Multivariate analysis showed that pre-Tg level over 16.79 ng/ml [OR: 6.55 (2.10-20.39), p=0.001] was the only independent predictor for NER in PTMC with RAIT. We found that high level of pre-Tg predicted a poor RAIT outcome in PTMC. Our finding explores a prospective way in identifying high-risk PTMCs with poor response to RAIT.

Fluorobenzene and Water-Promoted Rapid Growth of Vertical Graphene Arrays by Electric-Field-Assisted PECVD.

Vertical graphene (VG) arrays show exposed sharp edges, ultra-low electrical resistance, large surface-to-volume ratio, and low light reflectivity, thus having great potential in emerging applications, including field emission, sensing, energy storage devices, and stray light shields. Although plasma enhanced chemical vapor deposition (PECVD) is regarded as an effective approach for the synthesis of VG, it is still challenging to increase the growth rate and height of VG arrays simultaneously. Herein, a fluorobenzene and water-assisted method to rapidly grow VG arrays in an electric field-assisted PECVD system is developed. Fluorobenzene-based carbon sources are used to produce highly electronegative fluorine radicals to accelerate the decomposition of methanol and promote the growth of VG. Water is applied to produce hydroxyl radicals in order to etch amorphous carbon and accelerate the VG growth. The fastest growth rate can be up to 15.9 µm h-1 . Finally, VG arrays with a height of 144 µm are successfully synthesized at an average rate of 14.4 µm h-1 . As a kind of super black material, these VG arrays exhibit an ultra-low reflectance of 0.25%, showing great prospect in stray light shielding.

Markedly elevated serum preoperative thyroglobulin predicts radioiodine-refractory thyroid cancer.

BACKGROUND: Repeated radiotherapy brings limited benefits and significant side effects for differentiated thyroid cancer patients (DTC) with radioiodine refractory (RAIR). However, the prognostic role of preoperative thyroglobulin (pre-Tg) in predicting RAIR is unclear. METHODS: In the present study, data were retrospectively reviewed from 5173 patients who underwent radiotherapy in the Jiangyuan Hospital from January 2006 to December 2020. RESULTS: A total of 1,102 patients with or without repeated radiotherapy were compared (repeated vs. single radiotherapy; n = 199 vs. n = 903). Pre-Tg was significantly elevated in patients with repeated radiotherapy. After the classification of RAIR (non-RAIR, n = 786 vs. RAIR, n = 90), elevated pre-Tg was also correlated with RAIR after univariate and multivariate analyses. According to the receiver operating characteristic curve analysis, elevated pre-Tg well predicted RAIR (AUC = 0.76, CI: 0.71-0.82, p < 0.0001). To control the selection bias, the propensity score matching was used. Pre-Tg level was found to be an independent predictor of RAIR (p < 0.001, HR = 7.25, CI: 2.55-20.62). CONCLUSION: Our results indicate that markedly elevated pre-Tg level can be served as an independent predictor of RAIR-DTC, which can guide a more precise treatment strategy and/or an active surveillance during surgery and follow-ups.

Ultrafast Electrochemical Capacitors with Carbon Related Materials as Electrodes for AC Line Filtering.

High-frequency responsive electrochemical capacitors (ECs), which can directly convert alternating current (AC) to direct current (DC), are getting more essential for the rapid development of electronic devices. In order to satisfy the requirements of ECs with fast rate capability and appreciable capacitance density, numerous efforts have been made towards the preparation and design of the electrode material, which is a decisive factor in the performance of ECs. Carbon-related electrode materials have been widely shown to significantly increase the performance of ECs because of their light weight, high strength, and high processability. In this concept, the latest advances in the rational design and controllable fabrication of carbon-related electrode materials, including planar 2D materials, random 3D, and vertical carbon materials are summarized. Moreover, the state of the art of carbon-based ECs is discussed from the viewpoint of the structure of the electrode and performance of ECs. Finally, this concept presents integrated perspectives on the further design and preparation of carbon related ECs.

Capsaicin inhibits the stemness of anaplastic thyroid carcinoma cells by triggering autophagy-lysosome mediated OCT4A degradation.

Capsaicin (CAP) is a well-known anti-cancer agent. Recently, we reported capsaicin-induced apoptosis in anaplastic thyroid cancer (ATC) cells. It is well accepted that the generation of cancer stem cells (CSCs) is responsible for the dedifferentiation of ATC, the most lethal subtype of thyroid cancer with highly dedifferentiation status. Whether CAP inhibited the ATC growth through targeting CSCs needed further investigation. In the present study, CAP was found to induce autophagy in ATC cells through TRPV1 activation and subsequent calcium influx. Meanwhile, CAP dose-dependently decreased the sphere formation capacity of ATC cells. The stemness-inhibitory effect of CAP was further by extreme limiting dilution analysis (ELDA). CAP significantly decreased the protein level of OCT4A in both 8505C and FRO cells. Furthermore, CAP-induced OCT4A degradation was reversed by autophagy inhibitors 3-MA and chloroquine, BAPTA-AM and capsazepine, but not proteasome inhibitor MG132. Collectively, our study firstly showed CAP suppressed the stemness of ATC cells partially via calcium-dependent autophagic degradation of OCT4A. Our study lent credence to the feasible application of capsaicin in limiting ATC stemness.

Protective effect of surface-layer proteins from four Lactobacillus strains on tumor necrosis factor-α-induced intestinal barrier dysfunction.

BACKGROUND: The intestinal epithelium is considered the first defense protection against exogenous harmful substances, playing an indispensable role in regulating intestinal health. The protection offered by surface-layer proteins (Slps) from different Lactobacillus strains on an impaired intestinal barrier was investigated in this study. RESULTS: Four Slps pre-incubated for 6 h significantly prevented the reduced transepithelial electrical resistance value and increased paracellular permeability in tumor necrosis factor (TNF)-α-induced Caco-2 monolayers. TNF-α induced lower protein expression of occludin and zonula occludens-1, and abnormal distributions of occludin and zonula occludens-1 were ameliorated by four Slps as well. Additionally, four Slps weakened TNF-α-evoked interleukin-8 secretion and nuclear factor-κB activation. CONCLUSION: Four Slps from different strains prevent the intestinal barrier from TNF-α-induced dysfunction through blocking the nuclear factor-κB signaling pathway. © 2022 Society of Chemical Industry.

MKL1 overexpression predicts poor prognosis in patients with papillary thyroid cancer and promotes nodal metastasis.

Papillary thyroid cancer (PTC), the most common thyroid malignancy, has a strong propensity for cervical lymph node metastasis (LNM), which increases the risk of locoregional recurrence and decreases survival probability in some high-risk groups. Hence, there is a pressing requirement for a reliable biomarker to predict LNM in thyroid cancer. In the present study, MKL1 (also known as MRTFA) expression was significantly increased in PTC patients with LNM compared with those without. Further receiver operating characteristic (ROC) analysis showed that MKL1 expression had a diagnostic value in the differentiation of LNM in PTC. Furthermore, Kaplan-Meier analysis revealed that high MKL1 expression was associated with significantly decreased survival in PTC. Additionally, our study indicated that MKL1 promoted the migration and invasion of PTC cells. MKL1 interacted with and recruited Smad3 to the promoter of MMP2 to activate MMP2 transcription upon treatment with TGF-ß. Moreover, there was significant correlation between expression of TGF-ß, MKL1 and MMP2 in our clinical cohort of specimens from individuals with PTC. Our results suggest that the detection of MKL1 expression could be used to predict cervical LNM and inform post-operative follow-up in individuals with PTC.

Vitamin C induces ferroptosis in anaplastic thyroid cancer cells by ferritinophagy activation.

Anaplastic thyroid cancer (ATC) is a rare but highly lethal disease. So far, there is no available established treatment which can prolong its survival. In this regard, effective therapies are urgently needed. Vitamin C widely serves as an anti-cancer agent. However, the potential effects of vitamin C against thyroid tumorigenesis remained unclear. The present study demonstrated that vitamin C could significantly inhibit ATC cells growth through ferroptosis activation, evidenced by the GPX4 inactivation, ROS accumulation and iron-dependent lipid peroxidation. Our results demonstrated that vitamin C treatment induced ferritinophagy and subsequent degradation of ferritin, leading to the release of free iron. Excessive iron further triggered ROS generation via Fenton reaction. The positive feedback mediated by ROS and iron sustained lipid peroxidation and further resulted in ferroptosis of ATC cells. The better understanding of the anti-cancer mechanisms of vitamin C provides a potential strategy for ATC therapy.

Diallyl trisulphide, a H2 S donor, compromises the stem cell phenotype and restores thyroid-specific gene expression in anaplastic thyroid carcinoma cells by targeting AKT-SOX2 axis.

It is widely accepted that anaplastic thyroid carcinoma (ATC), a rare, extremely aggressive malignant, is enriched by cancer stem cells (CSCs), which are closely related to the pathogenesis of ATC. In the present study, we demonstrated that diallyl trisulphide (DATS), a well-known hydrogen sulphide (H2 S) donor, suppressed sphere formation and restored the expression of iodide-metabolizing genes in human ATC cells, which were associated with H2 S generation. Two other H2 S donors, NaHS and GYY4137, could also suppress the self-renewal properties of ATC cells in vitro. Compared with normal thyroid tissues and papillary thyroid carcinomas (PTCs), the elevated expressions of SOX2 and MYC, two cancer stem cell markers, in ATCs were validated in the combined Gene Expression Omnibus (GEO) cohort. DATS decreased the expression of SOX2, which was mediated by H2 S generation. Furthermore, knockdown of AKT or inhibition of AKT by DATS led to a decrease of SOX2 expression in ATC cells. AKT knockdown phenocopied restoration of thyroid-specific gene expression in ATC cells. Our data suggest that H2 S donors treatment can compromise the stem cell phenotype and restore thyroid-specific gene expression of ATC cells by targeting AKT-SOX2 pathway, which may serve as a therapeutic strategy to intervene the CSC progression of ATC.

Vertical Graphene Arrays as Electrodes for Ultra-High Energy Density AC Line-Filtering Capacitors.

High-frequency responsive electrochemical capacitor (EC), as an ideal lightweight filtering capacitor, can directly convert alternating current (AC) to direct current (DC). However, current electrodes are stuck in limited electrode area and tortuous ion transport. Herein, strictly vertical graphene arrays (SVGAs) prepared by electric-field-assisted plasma enhanced chemical vapour deposition have been successfully designed as the main electrode to ensure ions rapidly adsorb/desorb in richly available graphene surface. SVGAs exhibit an outstanding specific areal capacitance of 1.72 mF cm-2 at Φ120 =80.6° even after 500 000 cycles, which is far better than that of most carbon-related materials. Impressively, the output voltage could also be improved to 2.5 V when using organic electrolyte. An ultra-high energy density of 0.33 µWh cm-2 can also be handily achieved. Moreover, ECs-SVGAs can well smooth arbitrary AC waveforms into DC signals, exhibiting excellent filtering performance.

Diallyl trisulfide, a H2 S donor, inhibits cell growth of human papillary thyroid carcinoma KTC-1 cells through a positive feedback loop between H2 S and cystathionine-gamma-lyase.

Diallyl trisulfide (DATS), derived from garlic, is a well-known hydrogen sulfide (H2 S) donor. H2 S has recently emerged as a novel gasotransmitter involved in the regulation of cancer progression. The present study demonstrated that DATS along with other two H2 S donors, NaHS and GYY4137, significantly inhibited papillary thyroid carcinoma KTC-1 cells growth. DATS treatment triggered a rapid H2 S generation within 5 min in KTC-1 cells. Iodoacetamide, a potent thiol blocker reagent, partially rescued the cell membrane damage and ultimate cell death induced by DATS, indicating H2 S contributed to the apoptosis-inducing efficacy of DATS on thyroid cancer cells. Specifically, DATS treatment significantly upregulated the expression and enzymatic activity of cystathionine gamma-lyase (CTH), one of H2 S-producing enzymes, which was responsible for endogenous H2 S generation. After DATS treatment, H2 S quickly permeated cell membranes and activated NF-κΒ/p65 signaling pathway in KTC-1 cells. Nuclear translocated NF-κB bound to the promoter of CTH to enhance its transcription. These evidences proved that exogenous H2 S elevated CTH expression. CTH, in turn, catalytically generated a much higher level of endogenous H2 S. This positive feedback sustained excess H2 S production, which resulted in PTC cells growth inhibition. These findings may shed light on the development of novel H2 S-based antitumor agents.

[Progress in hepatocyte status detection and its application in bioartificial liver support system].

Bioartificial liver support system (BALSS) provides a new way to treat liver failure and leaves more time for patients who are waiting for liver transplantation. It has detoxification function as well as the human liver, at the same time it can provide nutrition and improve the internal environment inside human body. Bioreactors and hepatocytes with good biological activity are the cores of BALSS which determine the treatment effect. However, in the course of prolonged treatment, the function and activity of hepatocytes might be greatly changed which could influence the efficacy. Therefore, it is very important to detect the status of the hepatocytes in BALSS. This paper presents some common indicators of cell activity, detoxification and synthetic functions, and also introduces the commonly detection methods corresponding to each indicator. Finally, we summarize the application of detection methods of the hepatocyte status in BALSS and discuss its development trend.

Obesity and Cardiovascular Diseases in a High-Risk Population: Evidence-Based Approach to CHD Risk Reduction.

BACKGROUND: Obesity is becoming a worldwide public health problem and it is expected to worsen as its prevalence is increasing in children and adolescents. This report examined the distribution of major cardiovascular disease (CVD) risk factors and the effect of life-style changes on coronary heart disease (CHD) risk prediction in a high risk obese African Americans. METHODS: We examined the baseline distribution of CVD risk factors in 515 obese African Americans, with mean BMI of 42.9 ± 6.8 kg/m2, and prospectively the effect of a 6-month low-salt, low-fat diet and aerobic-exercise intervention program on risk reduction. RESULTS: Prevalence of hypertension, dyslipidemia, and diabetes mellitus were 57%, 27% and 24% respectively. Metabolic syndrome was present in 36% and 39% met two features of the syndrome. The 10-year risk prediction for developing CHD ranged from 4% to 17% for women and 6% to 29% for men. After 6 months of life-style changes, many of the risk factors improved, and the CHD risk scores decreased from 6% to 4% in the women and 16% to 13% in the men. CONCLUSION: The high prevalence and increasing incidence of obesity and associated cardiovascular risk emphasizes the need to focus on obesity reduction in this high risk population.

Programmed multimaterial assembly by synergized 3D printing and freeform laser induction.

In nature, structural and functional materials often form programmed three-dimensional (3D) assembly to perform daily functions, inspiring researchers to engineer multifunctional 3D structures. Despite much progress, a general method to fabricate and assemble a broad range of materials into functional 3D objects remains limited. Herein, to bridge the gap, we demonstrate a freeform multimaterial assembly process (FMAP) by integrating 3D printing (fused filament fabrication (FFF), direct ink writing (DIW)) with freeform laser induction (FLI). 3D printing performs the 3D structural material assembly, while FLI fabricates the functional materials in predesigned 3D space by synergistic, programmed control. This paper showcases the versatility of FMAP in spatially fabricating various types of functional materials (metals, semiconductors) within 3D structures for applications in crossbar circuits for LED display, a strain sensor for multifunctional springs and haptic manipulators, a UV sensor, a 3D electromagnet as a magnetic encoder, capacitive sensors for human machine interface, and an integrated microfluidic reactor with a built-in Joule heater for nanomaterial synthesis. This success underscores the potential of FMAP to redefine 3D printing and FLI for programmed multimaterial assembly.

Direct Growth of Vertical Graphene on Fiber Electrodes and Its Application in Alternating Current Line-Filtering Capacitors.

Fiber-shaped electrochemical capacitors (FSECs) have garnered substantial attention to emerging portable, flexible, and wearable electronic devices. However, achieving high electronic and ionic conductivity in fiber electrodes while maintaining a large specific surface area is still a challenge for enhancing the capacitance and rapid response of FSECs. Here, we present an electric-field-assisted cold-wall plasma-enhanced chemical vapor (EFCW-PECVD) method for direct growth of vertical graphene (VG) on fiber electrodes, which is incorporated in the FSECs. The customized reactor mainly consists of two radio frequency coils: one for plasma generation and the other for substrate heating. Precise temperature control can be achieved by adjusting the conductive plates and the applied power. With induction heating, only the substrate is heated to above 500 °C within just 5 min, maintaining a low temperature in the gas phase for the growth of VG with a high quality. Using this method, VG was easily grown on metallic fibers. The VG-coated titanium fibers for FSECs exhibit an ultrahigh rate performance and quick ion transport, enabling the conversion of an alternating current signal to a direct current signal and demonstrating outstanding filtering capabilities.

Cathode-Electrolyte Interphase Engineering toward Fast-Charging LiFePO4 Cathodes by Flash Carbon Coating.

Lithium iron phosphate (LiFePO4, LFP) batteries are widely used in electric vehicles and energy storage systems due to their excellent cycling stability, affordability and safety. However, the rate performance of LFP remains limited due to its low intrinsic electronic and ionic conductivities. In this work, an ex situ flash carbon coating method is developed to enhance the interfacial properties for fast charging. A continuous, amorphous carbon layer is achieved by rapidly decomposing the precursors and depositing carbon species in a confined space within 10 s. Simultaneously, different heteroatoms can be introduced into the surface carbon matrix, which regulates the irregular growth of cathode-electrolyte interphase (CEI) and selectively facilitates the inorganic region formation. The inorganic-rich, hybrid conductive CEI not only promotes electron and ion transport but also restricts parasitic side reactions. Consequently, LFP cathodes with fluorinated carbon coatings exhibited the highest capacity of 151 mAh g-1 at 0.2 C and 96 mAh g-1 at 10 C, indicating their excellent rate capability over commercial LFP (58 mAh g-1 at 10 C). This solvent-free, versatile surface modification is shown for other electrode materials, providing an efficient platform for electrode-electrolyte interphase engineering through a surface post-treatment.

Carbon nanotube fibers with dynamic strength up to 14 GPa.

High dynamic strength is of fundamental importance for fibrous materials that are used in high-strain rate environments. Carbon nanotube fibers are one of the most promising candidates. Using a strategy to optimize hierarchical structures, we fabricated carbon nanotube fibers with a dynamic strength of 14 gigapascals (GPa) and excellent energy absorption. The dynamic performance of the fibers is attributed to the simultaneous breakage of individual nanotubes and delocalization of impact energy that occurs during the high-strain rate loading process; these behaviors are due to improvements in interfacial interactions, nanotube alignment, and densification therein. This work presents an effective strategy to utilize the strength of individual carbon nanotubes at the macroscale and provides fresh mechanism insights.

Kinetically Controlled Synthesis of Metallic Glass Nanoparticles with Expanded Composition Space.

Nanoscale metallic glasses offer opportunities for investigating fundamental properties of amorphous solids and technological applications in biomedicine, microengineering, and catalysis. However, their top-down fabrication is limited by bulk counterpart availability, and bottom-up synthesis remains underexplored due to strict formation conditions. Here, a kinetically controlled flash carbothermic reaction is developed, featuring ultrafast heating (>105 K s-1) and cooling rates (>104 K s-1), for synthesizing metallic glass nanoparticles within milliseconds. Nine compositional permutations of noble metals, base metals, and metalloid (M1─M2─P, M1 = Pt/Pd, M2 = Cu/Ni/Fe/Co/Sn) are synthesized with widely tunable particle sizes and substrates. Through combinatorial development, a substantially expanded composition space for nanoscale metallic glass is discovered compared to bulk counterpart, revealing that the nanosize effect enhances glass forming ability. Leveraging this, several nanoscale metallic glasses are synthesized with composition that have never, to the knowledge, been synthesized in bulk. The metallic glass nanoparticles exhibit high activity in heterogeneous catalysis, outperforming crystalline metal alloy nanoparticles.

Electrothermal mineralization of per- and polyfluoroalkyl substances for soil remediation.

Per- and polyfluoroalkyl substances (PFAS) are persistent and bioaccumulative pollutants that can easily accumulate in soil, posing a threat to environment and human health. Current PFAS degradation processes often suffer from low efficiency, high energy and water consumption, or lack of generality. Here, we develop a rapid electrothermal mineralization (REM) process to remediate PFAS-contaminated soil. With environmentally compatible biochar as the conductive additive, the soil temperature increases to >1000 °C within seconds by current pulse input, converting PFAS to calcium fluoride with inherent calcium compounds in soil. This process is applicable for remediating various PFAS contaminants in soil, with high removal efficiencies ( >99%) and mineralization ratios ( >90%). While retaining soil particle size, composition, water infiltration rate, and cation exchange capacity, REM facilitates an increase of exchangeable nutrient supply and arthropod survival in soil, rendering it superior to the time-consuming calcination approach that severely degrades soil properties. REM is scaled up to remediate soil at two kilograms per batch and promising for large-scale, on-site soil remediation. Life-cycle assessment and techno-economic analysis demonstrate REM as an environmentally friendly and economic process, with a significant reduction of energy consumption, greenhouse gas emission, water consumption, and operation cost, when compared to existing soil remediation practices.