Data-Driven Structure Recognition of Scanning Tunneling Microscopy Images in a Case of Iron Carbide.

Scanning tunneling microscopy (STM) serves as a critical tool for high-resolution surface imaging, yet deciphering the atomic structures from STM images on multielement surfaces, such as oxides and carbides, remains a challenging task that heavily relies on the expertise and intuition of researchers. In this study, we introduce a data-driven method for rapid structural recognition from STM images. This method involves extracting structural features, filtering through a structural database, and matching with simulated STM images and surface energy analyses, thereby providing researchers with several of the most probable structures. We demonstrate the capabilities of this technique using our previously reported iron carbide grown on an Fe(110) crystal. By proposing a candidate structure set and establishing a comprehensive database linking STM images to corresponding structures and surface energies, we selected 6 out of more than 10 000 possible surfaces. On the basis of these 6 recommendations, researchers can conveniently determine the real surface structures. Our work provides an efficient tool for the structure recognition of STM images to construct surface structures, potentially serving as a universal auxiliary tool for STM structural analysis.

The first high-altitude autotetraploid haplotype-resolved genome assembled (Rhododendron nivale subsp. boreale) provides new insights into mountaintop adaptation.

BACKGROUND: Rhododendron nivale subsp. boreale Philipson et M. N. Philipson is an alpine woody species with ornamental qualities that serve as the predominant species in mountainous scrub habitats found at an altitude of ∼4,200 m. As a high-altitude woody polyploid, this species may serve as a model to understand how plants adapt to alpine environments. Despite its ecological significance, the lack of genomic resources has hindered a comprehensive understanding of its evolutionary and adaptive characteristics in high-altitude mountainous environments. FINDINGS: We sequenced and assembled the genome of R. nivale subsp. boreale, an assembly of the first subgenus Rhododendron and the first high-altitude woody flowering tetraploid, contributing an important genomic resource for alpine woody flora. The assembly included 52 pseudochromosomes (scaffold N50 = 42.93 Mb; BUSCO = 98.8%; QV = 45.51; S-AQI = 98.69), which belonged to 4 haplotypes, harboring 127,810 predicted protein-coding genes. Conjoint k-mer analysis, collinearity assessment, and phylogenetic investigation corroborated autotetraploid identity. Comparative genomic analysis revealed that R. nivale subsp. boreale originated as a neopolyploid of R. nivale and underwent 2 rounds of ancient polyploidy events. Transcriptional expression analysis showed that differences in expression between alleles were common and randomly distributed in the genome. We identified extended gene families and signatures of positive selection that are involved not only in adaptation to the mountaintop ecosystem (response to stress and developmental regulation) but also in autotetraploid reproduction (meiotic stabilization). Additionally, the expression levels of the (group VII ethylene response factor transcription factors) ERF VIIs were significantly higher than the mean global gene expression. We suspect that these changes have enabled the success of this species at high altitudes. CONCLUSIONS: We assembled the first high-altitude autopolyploid genome and achieved chromosome-level assembly within the subgenus Rhododendron. In addition, a high-altitude adaptation strategy of R. nivale subsp. boreale was reasonably speculated. This study provides valuable data for the exploration of alpine mountaintop adaptations and the correlation between extreme environments and species polyploidization.

Direct Ink Writing of SiCN/RuO2/TiB2 Composite Ceramic Ink for High-Temperature Thin-Film Sensors.

Direct ink writing (DIW) of high-temperature thin-film sensors holds significant potential for monitoring extreme environments. However, existing high-temperature inks face a trade-off between cost and performance. This study proposes a SiCN/RuO2/TiB2 composite ceramic ink. The added TiB2, after annealing in a high-temperature atmospheric environment, forms B2O3 glass, which synergizes with the SiO2 glass phase formed from the SiCN precursor to effectively encapsulate RuO2 particles. This enhances the film's density and adhesion to the substrate, preventing RuO2 volatilization at high temperatures. Additionally, the high conductivity of TiB2 improves the film's overall conductivity. Test results indicate that the SiCN/RuO2/TiB2 film exhibits high linearity from room temperature to 900 °C, high stability (resistance drift rate of 0.1%/h at 800 °C), and high conductivity (4410 S/m). As a proof of concept, temperature sensors and a heat flux sensor were successfully fabricated on a metallic hemispherical surface. Performance tests in extreme environments using high-power lasers and flame guns verified that the conformal thin-film sensor can accurately measure spherical temperature and heat flux, with a heat flux sensor response time of 53 ms. In conclusion, the SiCN/RuO2/TiB2 composite ceramic ink developed in this study offers a high-performance and cost-effective solution for high-temperature conformal thin-film sensors in extreme environments.

Hepatic arterial infusion of GEMOX plus systemic gemcitabine chemotherapy combined with lenvatinib and PD-1 inhibitor in large unresectable intrahepatic cholangiocarcinoma.

PURPOSE: To assess the efficacy and safety of hepatic arterial infusion chemotherapy (HAIC) of gemcitabine and oxaliplatin (GEMOX) plus systemic gemcitabine chemotherapy (GEM-SYS) in combination with lenvatinib and programmed cell death protein-1 (PD-1) inhibitor for patients with large unresectable intrahepatic cholangiocarcinoma (uICC). METHODS: From November 2019 to December 2022, 21 large uICC patients who underwent GEMOX-HAIC (Day 1) and GEM-SYS (Day 8) (3w/cycle) combined with lenvatinib and PD-1 inhibitor were retrospectively enrolled. Local tumor response, progression-free survival (PFS), overall survival (OS), and adverse events (AEs) were analyzed. Tumor response was assessed by the Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1. AEs were evaluated by the common terminology criteria for adverse events (CTCAE) version 5.0. RESULTS: After a median follow-up duration of 16.0 months (range 5-43.5 months), 17 patients had died. The median OS was 19.5 months (range 9-43.5 months), and the median PFS was 6.0 months (range 2.5-38.5 months). The 1-, 2-, and 3-year OS rates were 71.4 %, 42.9 %, and 19.0 %, respectively. The 1-, 2-, and 3-year PFS rates were 33.3 %, 19.0 %, and 9.5 %, respectively. Complete response, partial response, stable disease, and progressive disease were observed in 0 (0 %), 11 (52.3 %), 5 (23.8 %), and 5 (23.8 %) patients, respectively. The disease control rate and objective response rate were 76.1 % and 52.3 %, respectively. None of the enrolled patients experienced grade 5 AEs. CONCLUSIONS: GEMOX-HAIC plus GEM-SYS in combination with lenvatinib and PD-1 inhibitor was effective and well tolerated for patients with large uICC.

Spatiotemporal geographically weighted regression analysis for runoff variations in the Weihe River Basin.

In order to investigate the effects of vegetation changes on runoff and to obtain recommendations for improving runoff in the Weihe River Basin (. In this study, a spatiotemporal geographic autocorrelation weighted regression analysis (SGAWRA) approach was newly developed based on previous studies. This approach investigates spatial non-stationarity of the dynamic response from vegetation variations to climatic change and human activity. Implications of spatial non-stationarity related to runoff variability were also discussed, which in turn yield the effect that vegetation changes have on runoff. The method systematically analysed the spatial non-stationarity of vegetation variations and its associated effects on runoff. Therefore, more closely related results with less error were produced at each step, and results with more accuracy were obtained. These results indicated that the average trend rates of NDVI in the annual average, each season, and the growing season (Growing season refers to April to September) exceeded 0. Areas where NDVI show a growing trend cover more than 50%, which is greater than the area with a decreasing trend. The GWR regression parameters of precipitation, average temperature, and NDVI are all greater than 0. The GWR regression parameters of human activities and NDVI also have more than 50% of the area greater than 0. Based on the visual analysis of the calculation results, it can be seen that there are obvious spatial trends in the data, and the spatial data are significantly different between different regions. Therefore, WRB can be regarded as spatio-temporally non-stationary. In the WRB, the underlying surface change with vegetation change as the prominent feature is the leading cause (about 60%) of the runoff attenuation. The results showed that WRB has spatial and temporal non-stationarity. The spatial non-stationarity of vegetation has a greater effect on runoff changes. The results of this study support recommendations for improving runoff in the WRB.

Citrate and low-dose heparin combined anticoagulation in pediatric continuous renal replacement therapy.

There remains no optimal anticoagulation protocol for continuous renal replacement therapy (CRRT) with regional citrate anticoagulation (RCA) in pediatric patients with elevated D-dimer levels. We aimed to assess the effects of different anticoagulation strategies on the risk of CRRT filter clotting in these patients. Pediatric patients undergoing CRRT were retrospectively grouped based on pre-CRRT D-dimer levels and anticoagulant: D-RCA group (normal D-dimer, RCA only, n = 22), D+ RCA group (elevated D-dimer, RCA only, n = 50), and D+ RCA+ systemic heparin anticoagulation (SHA) group (elevated D-dimer, RCA combined with SHA, n = 55). The risk of filter clotting and incidence of bleeding were compared among the groups. Among the groups, the D+ RCA+ SHA group had the longest filter lifespan; further, the incidence of bleeding was not increased by concurrent use of low-dose heparin for anticoagulation. Moreover, concurrent heparin anticoagulation was associated with a decreased risk of filter clotting. Contrastingly, high pre-CRRT hemoglobin and D-dimer levels and post-filter ionized calcium level > 0.4 mmol/L were associated with an increased risk of filter clotting. RCA combined with low-dose heparin anticoagulation could reduce the risk of filter clotting and prolong filter lifespan without increasing the risk of bleeding in patients with elevated D-dimer levels undergoing CRRT.

Drug screening on digital microfluidics for cancer precision medicine.

Drug screening based on in-vitro primary tumor cell culture has demonstrated potential in personalized cancer diagnosis. However, the limited number of tumor cells, especially from patients with early stage cancer, has hindered the widespread application of this technique. Hence, we developed a digital microfluidic system for drug screening using primary tumor cells and established a working protocol for precision medicine. Smart control logic was developed to increase the throughput of the system and decrease its footprint to parallelly screen three drugs on a 4 × 4 cm2 chip in a device measuring 23 × 16 × 3.5 cm3. We validated this method in an MDA-MB-231 breast cancer xenograft mouse model and liver cancer specimens from patients, demonstrating tumor suppression in mice/patients treated with drugs that were screened to be effective on individual primary tumor cells. Mice treated with drugs screened on-chip as ineffective exhibited similar results to those in the control groups. The effective drug identified through on-chip screening demonstrated consistency with the absence of mutations in their related genes determined via exome sequencing of individual tumors, further validating this protocol. Therefore, this technique and system may promote advances in precision medicine for cancer treatment and, eventually, for any disease.

Selective Cleavage of α-Olefins to Produce Acetylene and Hydrogen.

Acetylene production from mixed α-olefins emerges as a potentially green and energy-efficient approach with significant scientific value in the selective cleavage of C-C bonds. On the Pd(100) surface, it is experimentally revealed that C2 to C4 α-olefins undergo selective thermal cleavage to form surface acetylene and hydrogen. The high selectivity toward acetylene is attributed to the 4-fold hollow sites which are adept at severing the terminal double bonds in α-olefins to produce acetylene. A challenge arises, however, because acetylene tends to stay at the Pd(100) surface. By using the surface alloying methodology with alien Au, the surface Pd d-band center has been successfully shifted away from the Fermi level to release surface-generated acetylene from α-olefins as a gaseous product. Our study actually provides a technological strategy to economically produce acetylene and hydrogen from α-olefins.

Regioselective hydroformylation of propene catalysed by rhodium-zeolite.

Hydroformylation is an industrial process for the production of aldehydes from alkenes1,2. Regioselective hydroformylation of propene to high-value n-butanal is particularly important, owing to a wide range of bulk applications of n-butanal in the manufacture of various necessities in human daily life3. Supported rhodium (Rh) hydroformylation catalysts, which often excel in catalyst recyclability, ease of separation and adaptability for continuous-flow processes, have been greatly exploited4. Nonetheless, they usually consist of rotationally flexible and sterically unconstrained Rh hydride dicarbonyl centres, only affording limited regioselectivity to n-butanal5-8. Here we show that proper encapsulation of Rh species comprising Rh(I)-gem-dicarbonyl centres within a MEL zeolite framework allows the breaking of the above model. The optimized catalyst exhibits more than 99% regioselectivity to n-butanal and more than 99% selectivity to aldehydes at a product formation turnover frequency (TOF) of 6,500 h-1, surpassing the performance of all heterogeneous and most homogeneous catalysts developed so far. Our comprehensive studies show that the zeolite framework can act as a scaffold to steer the reaction pathway of the intermediates confined in the space between the zeolite framework and Rh centres towards the exclusive formation of n-butanal.

Platinum-based adjuvant chemoradiotherapy versus adjuvant radiotherapy in patients with head and neck adenoid cystic carcinoma.

PURPOSE: The objective of the study was to assess the effectiveness and toxicity of platinum-based adjuvant chemoradiotherapy (POCRT) in comparison to postoperative radiotherapy (PORT) in patients with head and neck adenoid cystic carcinoma (HNACC). MATERIALS AND METHODS: This retrospective study analyzed patients diagnosed with HNACC at our center between January 2010 and April 2020. A 1:1 propensity score matching method was used to create a matched cohort. RESULTS: In this study, 206 patients were analyzed, with 147 patients (71.4%) receiving postoperative radiotherapy (PORT) and 59 patients (28.6%) receiving POCRT. Twenty-one patients experienced local-regional failure. The 3-, 5-, and 10-yr local-regional control (LRC) rate for the cohort were 92.0%, 90.6%, and 86.9%, respectively. In both the entire cohort and the matched cohort, the POCRT group exhibited superior LRC compared to the PORT group (Gray's test, all P < 0.05*). Multivariate analysis identified adjuvant concurrent chemotherapy as an independent prognostic factor for LRC (Competing risks regression, HR = 0.144, 95% CI 0.026-0.802, P = 0.027*). In addition, the POCRT group had higher incidences of upper gastrointestinal toxicity and hematologic toxicities, including leukopenia, neutropenia, and anemia (all P < 0.05*). CONCLUSION: In terms of reducing locoregional failures in HNACC patients, POCRT may potentially offer a more effective therapeutic approach than using PORT alone, although it also entails an augmented burden of treatment-related toxicity.

Omission of radiotherapy to lymph node level III in patients with cN0 adenoid cystic carcinoma of the major salivary gland: a single center experience.

PURPOSE: Due to the rarity of adenoid cystic carcinoma (ACC) of the major salivary gland, there is no consensus on the extent of prophylactic neck irradiation (PNI) for patients with clinically negative lymph nodes (cN0) disease. MATERIALS AND METHODS: We conducted a retrospective analysis of all patients with ACC of the major salivary gland who received treatment at our center between January 2010 and April 2020. The primary endpoint was regional failure-free survival (RRFS). Secondary endpoints included overall survival (OS), distant metastasis-free survival (DMFS), local recurrence-free survival (LRFS), and acute toxicity. RESULTS: A total of 139 patients were included in the analysis. For cN0 patients, the 5-year RRFS, OS, DMFS, and LRFS were 93.2%, 90.2%, 75.7%, and 91.4%, respectively. Multivariate analysis revealed that PORT was an independent prognostic factor for RRFS and LRFS. No statistically significant differences were observed between the Level III sparing PNI group and the Standard PNI group in terms of RRFS, OS, DMFS, and LRFS. The doses delivered to the larynx and thyroid in the Level III sparing PNI group were significantly lower than those in the Standard PNI group. CONCLUSION: In patients with cN0 ACC of the major salivary gland, PNI improves regional control, and the level III nodal region sparing radiotherapy does not increase the risk of level III recurrence, while potentially reducing toxicity.

The effect of surgical starting time on elective colorectal cancer surgery: A propensity score matching analysis.

The purpose of the current study is to analyze whether surgical starting time affects the short-term outcomes of elective colorectal cancer (CRC) surgery. We retrospectively collected CRC patients who underwent elective surgery from Jan 2008 to Jan 2021 in a single clinical center. The effect of surgical starting time (morning surgery vs afternoon surgery, day surgery vs night surgery) on elective CRC surgery was analyzed using propensity score matching (PSM). A total of 6783 patients were included in the current study. There were 5751 patients in day surgery group and 1032 patients in night surgery group, and there were 2920 patients in morning surgery group and 2831 patients in afternoon surgery group. After 1:1 ratio PSM, there were no significant difference in terms of the baseline information (P > .05). Day surgery group had longer operation time (P = .000) and longer hospital stay (P = .029) than night surgery group after PSM. Morning surgery group had longer operation time than afternoon surgery group before PSM (P = .000) and after PSM (P = .000). Univariate and multivariate analysis of the total of 6783 patients were conducted to find predictors of complications, and found that night surgery was a predictor of major complications (P = .002, OR = 1.763, 95% CI = 1.222-2.543) but not a predictor of overall complications (P = .250, OR = 1.096, 95% CI = 0.938-1.282). Night surgery is a predictor of major complications after elective CRC surgery, therefore, surgeons should be careful when operating at night.

Novel stent-assisted ileal bypass is applied to avoid protective stoma and prevent anastomotic leakage for rectal cancer.

PURPOSE: This study aimed to investigate the safety and feasibility of a novel stent-assisted ileal bypass for rectal cancer patients who received sphincter-preserving surgery. METHODS: Patients who were diagnosed with rectal cancer and received sphincter-preserving surgery plus a novel stent-assisted ileal bypass were respectively included from January 2022 to January 2023. Biofragmentable ileal stent with diaphragm sheet in the cavity was placed in the terminal ileum using absorbable sutures after anastomosis. At the proximal end of the stent, an intestinal diversion tube was placed in the prefabricated purse-string, through which faeces were drained. The stent completely disintegrated in the body after 3-4 weeks, which protected the anastomosis after surgery and avoided protective stoma. Clinical characteristics and surgical outcomes were collected. RESULTS: Eleven patients who successfully received surgery were included. There were seven (63.6%) males and four (36.4%) females. The tumour size was 3.2 ± 1.7 cm and the lower verge of tumour to anal verge was 6.8 ± 1.3 cm. As for surgical outcomes, operation time was 216.4 ± 54.1 min, blood loss was 43.6 ± 64.6 mL, time to first flatus via intestinal diversion tube was 3.2 ± 1.1 days, time to discharge stent was 22.8 ± 3.0 days, and postoperative hospital stay was 21.0 ± 5.4 days. Two patients suffered from postoperative complications including pneumonia and incision infection. CONCLUSION: This novel stent-assisted ileal bypass is safe and feasible, it provides a new choice for rectal cancer patients to avoid protective stoma and secondary surgery.

Rapid laser fabrication of indium tin oxide and polymer-derived ceramic composite thin films for high-temperature sensors.

Thin-film sensors are essential for real-time monitoring of components in high-temperature environments. Traditional fabrication methods often involve complicated fabrication steps or require prolonged high-temperature annealing, limiting their practical applicability. Here, we present an approach using direct ink writing and laser scanning (DIW-LS) to fabricate high-temperature functional thin films. An indium tin oxide (ITO)/preceramic polymer (PP) ink suitable for DIW was developed. Under LS, the ITO/PP thin film shrank in volume. Meanwhile, the rapid pyrolysis of PP into amorphous precursor-derived ceramic (PDC) facilitated the faster sintering of ITO nanoparticles and improved the densification of the thin film. This process realized the formation of a conductive network of interconnected ITO nanoparticles. The results show that the ITO/PDC thin film exhibits excellent stability, with a drift rate of 4.7 % at 1000 °C for 25 h, and withstands temperatures up to 1250 °C in the ambient atmosphere. It is also sensitive to strain, with a maximum gauge factor of -6.0. As a proof of concept, we have used DIW-LS technology to fabricate a thin-film heat flux sensor on the surface of the turbine blade, capable of measuring heat flux densities over 1 MW/m2. This DIW-LS process provides a viable approach for the integrated, rapid, and flexible fabrication of thin film sensors for harsh environments.

Identification of image genetic biomarkers of Alzheimer's disease by orthogonal structured sparse canonical correlation analysis based on a diagnostic information fusion.

Alzheimer's disease (AD) is an irreversible neurodegenerative disease, and its incidence increases yearly. Because AD patients will have cognitive impairment and personality changes, it has caused a heavy burden on the family and society. Image genetics takes the structure and function of the brain as a phenotype and studies the influence of genetic variation on the structure and function of the brain. Based on the structural magnetic resonance imaging data and transcriptome data of AD and healthy control samples in the Alzheimer's Disease Neuroimaging Disease database, this paper proposed the use of an orthogonal structured sparse canonical correlation analysis for diagnostic information fusion algorithm. The algorithm added structural constraints to the region of interest (ROI) of the brain. Integrating the diagnostic information of samples can improve the correlation performance between samples. The results showed that the algorithm could extract the correlation between the two modal data and discovered the brain regions most affected by multiple risk genes and their biological significance. In addition, we also verified the diagnostic significance of risk ROIs and risk genes for AD. The code of the proposed algorithm is available at https://github.com/Wanguangyu111/OSSCCA-DIF.

Clinical application of a novel stent-assisted in situ intestinal bypass in preventing postoperative anastomotic leakage for low-mid rectal cancer: A retrospective study.

This study aimed to investigate the safety and feasibility of a novel stent-assisted in situ intestinal bypass for low-mid rectal cancer patients. Patients who were diagnosed with rectal cancer and received laparoscopic low anterior rectal resection plus a novel stent-assisted in situ intestinal bypass were respectively included from March 2022 to June 2022. Biofragmentable intestinal stent with a protective sleeve was placed in the proximal colon before anastomosis, and feces could be discharged through the protective sleeve without touching the anastomosis, which achieved an in situ bypass of feces. Perioperative characteristics and short-term outcomes were collected. Rectal imaging was performed each week after surgery for the first 3 weeks to surveil the stent and feces delivery. Follow-ups were conducted for more than 3 months. Thirty patients who successfully received surgery were included in this study. There were 18 (60.0%) males and 12 (40.0%) females. As for perioperative characteristics, operation time was 213.8 ± 43.0 minutes, blood loss was 53.3 ± 24.6 mL, time to first flatus via protective sleeve after surgery was 3.2 ± 1.1 days, postoperative hospital stay was 11.8 ± 1.6 days, and time to discharge stent was 22.4 ± 3.2 days. As for short-term outcomes, 6 patients suffered from pneumonia, urinary tract infection or incision infection. During the follow-up, there was no anastomotic leakage or mortality. This novel stent-assisted in situ intestinal bypass is safe and feasible, it might be an applicable way to prevent postoperative anastomotic leakage for patients with low-mid rectal cancer.

Emphysematous thrombophlebitis caused by a misplaced central venous catheter: A case report.

BACKGROUND: Central venous catheters (CVCs) often cause life-threatening complications, especially CVC-related bloodstream infection (CVC-BSI) and catheter-related thrombosis (CRT). Here, we report an unusual case of misplaced CVC-induced emphysematous thrombophlebitis, a rare but potentially lethal form of CRT and CVC-BSI characterized by both thrombosis and gas formation. CASE SUMMARY: A 48-year-old male presented to the emergency room of a local hospital with sudden-onset headache and coma for 4 h. Computed tomography (CT) revealed right basal ganglia hemorrhage, so emergency decompressive craniotomy was performed and a CVC was inserted through the right subclavian vein for fluid resuscitation during anesthesia. Two days later, the patient was transferred to the intensive care unit of our hospital for further critical care. On day 9 after CVC insertion, the patient suddenly developed fever and hypotension. Point-of-care ultrasound (POCUS) demonstrated thrombosis and dilatation of the right internal jugular vein (IJV) filled with thrombosis. Ultrasonography also revealed that the CVC tip had been misplaced into the IJV and was surrounded by gas bubbles, which manifested as hyperechoic lines with dirty shadowing and comet-tail artifacts. Further CT scan confirmed air bubbles surrounding the CVC in the right neck. The final diagnosis was septic emphysematous thrombophlebitis induced by a misplaced CVC and ensuing septic shock. The responsible CVC was removed immediately. The patient received fluid resuscitation, intravenous noradrenaline, and a 10-d ultra-broad spectrum antibiotic treatment to combat septic shock. Both CVC and peripheral venous blood cultures yielded methicillin-resistant Staphylococcus cohnii. The patient was gradually weaned off vasopressors and the symptoms of redness and swelling in the right neck subsided within 7 d. CONCLUSION: Emphysematous thrombophlebitis is a fulminant and life-threatening CVC-BSI associated with thrombosis and gas formation in the vein. A misplaced CVC may facilitate the development of emphysematous thrombophlebitis. POCUS can easily identify the artifacts produced by gas and thrombosis, facilitating rapid diagnosis at the bedside.

Molecular Evidence of Structural Changes in Silk Using Unlimited Degradation Mass Spectrometry.

Proteomics has important uses in archeological science because it can distinguish species, reveal the evolution of paleontology, and provide biological evidence of historical events. However, this technique still has full potential in the study of silk aging mechanisms. In this work, we propose a strategy combining unlimited degradation with mass-spectrometry-based proteomics techniques, which interpret protein fragmentation propensity and secondary structure changes by detecting content changes of specific peptide groups in complex proteomes. This approach was employed to study the conformational changes in silk microscopic crystals after heat treatment. Combining conventional mechanics and crystallographic characterization, a thermal aging degradation mechanism model was proposed. At the same time, it explained the interesting problem that the crystallinity remained unchanged, but the mechanical properties decreased significantly. Focusing on the unlimited degradation process, this method will be widely applicable to the study of silk and wool aging processes and regenerated silk fibroin.

Magnetic field improves ozone production in an atmospheric pressure surface dielectric barrier discharge: understanding the physico-chemical mechanism behind low energy consumption.

Herein, we studied the combined effects of the magnetic field and the alternating current driven air surface dielectric barrier discharge on ozone production, and found that a 0.13 T perpendicular magnetic field introduced into the discharge area significantly enhanced the ozone generation performance with a 36-108% increase in ozone number density and 24-80% increase in ozone yield depending on discharge voltage and frequency differences. To reveal the micro physico-chemical mechanism of the influence of a magnetic field and discharge parameters of discharge voltage and frequency on ozone generation, a plasma chemical reaction network involving electron collision-chain reactions was considered. The results show that these parameters jointly influence ozone generation by affecting electron collision reactions and chain chemical reactions by changing the mean electron energy and plasma gas temperature. In this study, both the experimental results and mechanism analysis suggested that an optimal discharge parameter for ozone generation is the magnetic field assisted, low frequency, high voltage (6.5 kHz, 6.5 kV) surface dielectric barrier discharge. These insights provide guidance for optimizing the discharge parameters of the magnetic field assisted discharge to increase ozone production and reduce energy consumption.

ROS-mediated MAPK activation aggravates hyperoxia-induced acute lung injury by promoting apoptosis of type II alveolar epithelial cells via the STAT3/miR-21-5p axis.

Inhibition of type II alveolar epithelial (AE-II) cell apoptosis is a critical way to cure hyperoxia-induced acute lung injury (HALI). It has been reported that miR-21-5p could reduce H2O2-induced apoptosis in AE-II cells. However, the upstream molecular mechanism remains unclear. Herein, we established a cellular model of HALI by exposing AE-II cells to H2O2 treatment. It was shown that miR-21-5p alleviated H2O2-induced apoptosis in AE-II cells. ROS inhibition decreased apoptosis of H2O2-evoked AE-II cells via increasing miR-21-5p expression. In addition, ROS induced MAPK and STAT3 phosphorylation in H2O2-treated AE-II cells. MAPK inactivation reduces H2O2-triggered AE-II cell apoptosis. MAPK activation inhibits miR-21-5p expression by promoting STAT3 phosphorylation in H2O2-challenged AE-II cells. Furthermore, STAT3 activation eliminated MAPK deactivation-mediated inhibition on the apoptosis of AE-II cells under H2O2 condition. In conclusion, ROS-mediated MAPK activation promoted H2O2-triggered AE-II cell apoptosis by inhibiting miR-21-5p expression via STAT3 phosphorylation, providing novel targets for HALI treatment.