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Direct conversion of syngas to aromatics (STA) over oxide-zeolite composite catalysts is promising as an alternative method for aromatics production. However, the structural effect of the oxide component in composite catalysts is still ambiguous. Herein, we investigate the size effect by selecting ZnCr2O4 spinel, as a probe oxide, mixing with H-ZSM-5 zeolite as a composite catalyst for STA reaction. The CO conversion, aromatics selectivity and space-time yield (STY) of aromatics are all significantly improved with the crystal size of ZnCr2O4 oxide decreases, which can mainly attribute to the higher oxygen vacancy concentration and thus the rapid generation of more C1 oxygenated intermediate species. Based on the understanding of the size–performance relationship, ZnCr2O4-400 with a smaller size mixing with H-ZSM-5 can achieve 32.6% CO conversion with 76% aromatics selectivity. The STY of aromatics reaches as high as 4.79 mmol gcat−1 h−1, which outperforms the previously reported some typical catalysts. This study elucidates the importance of regulating the size of oxide to design more efficient oxide-zeolite composite catalysts for conversion of syngas to value-added chemicals.

Raman spectroscopy uncovered molecular scale markers of the viral structure of the SARS-CoV-2 Delta variant and related viral inactivation mechanisms at the biological interface with silicon nitride (Si

Realizing high CO conversion and high aromatics selectivity simultaneously in syngas-to-aromatics (STA) reaction is still challenging. Herein, we report a 57.5% CO conversion along with 74% aromatics selectivity over a composite catalyst consisting of Fe/ZnCr2O4 (Fe modified ZnCr2O4 spinel) oxide and H-ZSM-5 zeolite. Impregnation of only 3 wt% of Fe onto ZnCr2O4 can remarkably increase CO conversion without sacrificing the aromatics selectivity. Oxygen vacancy concentration is improved after impregnating Fe. The highly dispersed iron carbide species is formed during the reaction over Fe/ZnCr2O4 spinel oxide. The synergistic effect of oxygen vacancy and iron carbide results in a rapid formation of abundant oxygenated intermediate species, which can be continuously transformed to aromatics in H-ZSM-5. This study provides a new insight into the design of highly efficient catalyst for syngas conversion.

Purpose To compare the safety and efficacy of left versus right internal jugular vein access for portal vein puncture during transjugular intrahepatic portosystemic shunt (TIPS) creation in patients with a small liver and short vertical puncture distance. Materials and Methods The vertical distance from the hepatic vein orifice to the puncture point of the portal vein was measured by CT and DSA. A distance ≤ 30 mm is defined as a short vertical puncture distance. After 1:1 propensity score matching (PSM), 29 patients of left internal jugular vein-TIPS (LIJ-TIPS) and 29 patients of right internal jugular vein-TIPS (RIJ-TIPS) were included. The number of needle punctures, fluoroscopy time, and radiation dose during the puncture process were statistically analyzed. Results There was no significant difference in the average vertical puncture distances on CT or DSA between LIJ-TIPS and RIJ-TIPS (19.10 ± 0.60 mm vs. 19.30 ± 0.60 mm, P = 0.840; 22.02 ± 0.69 mm vs. 22.23 ± 0.64 mm, P = 0.822, respectively). The average number of needle punctures, fluoroscopy time, and radiation dose in LIJ-TIPS were significantly lower than those in RIJ-TIPS (2.07 ± 0.20 vs. 4.10 ± 0.24, P vs. 201.16 ± 23.71 s, P vs. 136.69 ± 16.38 mGy, P vs. 27.6%, P vs. 13.8%, P = 0.038). Conclusion The left internal jugular vein could be used as primary access for TIPS creation in patients with a small liver and short vertical puncture distance.

This study intends to investigate the effects of miR-142-5p encapsulated by serum-derived extracellular vesicles (EVs) on septic acute lung injury (ALI) following remote ischemic preconditioning (RIPC) through a PTEN-involved mechanism. ALI was induced in rats by lipopolysaccharide (LPS) injection, 24 h before which RIPC was performed via the left lower limb. Next, the binding affinity between miR-142-5p and PTEN was identified. EVs were isolated from serum and injected into rats. The morphology of lung tissues, pulmonary edema, and inflammatory cell infiltration into lung tissues were then assessed, and TNF-α and IL-6 levels in serum and lung tissues were measured. The results indicated that RIPC could attenuate ALI in sepsis. miR-142-5p expression was increased in serum, lung tissues, and serum-derived EVs of ALI rats following RIPC. miR-142-5p could target PTEN to activate the PI3K/Akt signaling pathway. miR-142-5p shuttled by serum-derived EVs reduced pulmonary edema, neutrophil infiltration, and TNF-α and IL-6 levels, thus alleviating ALI in LPS-induced septic rats upon RIPC. Collectively, serum-derived EVs-loaded miR-142-5p downregulated PTEN and activated PI3K/Akt to inhibit ALI in sepsis following RIPC, thus highlighting potential therapeutic molecular targets against ALI in sepsis.

An efficient and long-term stable nano-sized N-H-ZSM-5 zeolite catalyst for the one-step aldol condensation reaction of formaldehyde and MAc to produce MA and AA is reported. Its total lifetime reaches up to 226 h by three regeneration runs.

PURPOSE This study explored the clinical efficacy of transcatheter retrograde shunt occlusion with coils to prevent pulmonary oil or particle embolization prior to transarterial chemoembolization (TACE) in patients with artero-hepatic venous shunts (AHVS) secondary to hepatocellular carcinoma (HCC). METHODS From July 2017 to January 2021, 6 patients with advanced, unresectable HCC were found to have an AHVS by hepatic arteriography at the time of attempted TACE. The AHVS was embolized ret rogradely with metal coils through a transfemoral or transjugular venous approach. After venous embolization and confirmation of the absence of the AHVS, TACE was performed using an emul sion of iodized oil and doxorubicin or drug-eluting beads. Follow-up computed tomography (CT) was performed within 1 month after the first TACE to evaluate the results and complications. RESULTS Hepatic angiography after venous embolization showed that AHVS had utterly disappeared in all patients during the operation. The immediate technical success of the retrograde venous embo lization was 100%. The AHVS had disappeared entirely during the follow-up period through triple-phase enhancement CT scanning. According to the modified response evaluation criteria in solid tumors, TACE in all 6 patients had a disease control response rate of 100% (6/6) with complete response in 2 patients and partial response in 4 patients. One patient died during the 6-month follow-up, and the other 5 were still alive. No complications related to pulmonary embolism occurred. CONCLUSION Retrograde venous coil embolization of AHVS via the draining hepatic vein appears to be a safe, feasible, and effective treatment to allow TACE treatment without pulmonary embolic events. This approach appears to provide better tumor control and effectively decreases the occurrence of pulmonary embolism.

Hydrogenation of methyl acetate is a key step in ethanol synthesis from dimethyl ether carbonylation and Cu-based catalysts are widely studied. We report here that the hydrogenation activity of Cu/ZnO catalysts can be enhanced by the addition of MgO promoter. The evolution of crystal phases during coprecipitation and the physicochemical properties of calcined and reduced catalysts by X-ray diffraction (XRD), thermogravimetric (TG)-mass spectrometry (MS), Brunauer-Emmett-Teller (BET), transmission electron microscopy (TEM), N2O titration, in situ CO-Fourier transform infrared spectroscopy (FTIR) and H2-temperature programmed reduction (H2-TPR) reveal that the promoter effect likely lies in the presence of Mg2+. A proper amount of Mg2+ mediates the precipitation process of Cu and Zn, leading to preferable formation of aurichalcite (CuxZn1−x)5(CO3)2(OH)6 crystal phase and a small amount of basic carbonates such as hydrozincite Zn5(CO3)2(OH)6 and malachite Cu2CO3(OH)2. The presence of aurichalcite strengthens the interaction between Cu and Zn species, and thus enhances the dispersity of Cu0 species and helps generation of Cu+ species on reduced catalysts. Furthermore, the performance of Cu/ZnO catalysts exhibits an optimal dependence on the Mg loading, i.e., 17.5%. However, too much Mg2+ in the precipitation liquid prohibits formation of aurichalcite but enhances formation of basic nitrates, leading to a dramatically reduced hydrogenation activity. These findings may find applications for optimization of other Cu-based catalysts in a wider range of hydrogenation reactions.

Faraday-type electrode materials and devices for electrochemical capacitors have been widely investigated. However, their applications are severely limited by the preparation method and cost of electrode materials. In this work, high-performance electrochemical capacitors were successfully assembled using Fe

Summary Achieving high conversion of syngas to fuels and basic chemicals with excellent selectivity and stability remains a challenge. Here, we report an 80.6% selectivity of gasoline-range C5–11 hydrocarbons at 86.3% CO conversion over a dual-bed catalyst (CZA + Al2O3)/N-ZSM-5(97) that consists of an upper-bed syngas-to-dimethyl ether (DME) catalyst (CZA + Al2O3) and a lower-bed DME-to-gasoline catalyst (nano-sized N-ZSM-5(97) zeolite). This dual-bed catalyst exhibits an excellent stability in a 110-h reaction test. The iso/n-paraffin ratio in the C5–11 is up to 18. For the lower-bed zeolite catalyst, the nano-sized structure is beneficial to reduce coke and prolong lifetime; meanwhile, the low acid content is advantageous to increase C5–11 selectivity. The 2,3-dihydro-1H-inden-1-one species can be definitely detected and identified in the spent lower-bed micro-sized M-ZSM-5(18) catalyst. They are regarded as intermediates to generate polycyclic aromatics, which generally lead to catalyst deactivation. The dual-bed catalyst (CZA + Al2O3)/N-ZSM-5(97) suggests a promising application in producing gasoline from syngas.

Alcoholic hepatitis (AH), a kind of alcoholic liver disease, shows poor prognosis. Long noncoding RNAs (lncRNAs) exert critical role in liver diseases. Here, we intended to investigate the possible molecular mechanism that 1700020I14Rik-based regulation of microRNA (miR)-137/Aldo-keto reductase family 1 member B10 (AKR1B10) affecting the inflammatory response and hepatocyte damage in AH. AH-related genes and the down-stream regulatory pathway were screnned by bioinformatics. Mouse normal hepatocyte cell line AML12 was selected to construct an ethanol-induced hepatocyte injury model for in vitro mechanistic validation, while we also established an AH mouse model using the ethanol with gradually increased concentration of 2–4% (v/v) for in vivo study. Specific role of 1700020I14Rik/miR-137/AKR1B10 in AML12 cell viability, proliferation and apoptotic capacity as well as inflammation and liver damage in mice were analyzed following ectopic and depletion approaches. We found elevated AKR1B10 and 1700020I14Rik but reduced miR-137 in AH. 1700020I14Rik was able to elevated miR-137-mediated AKR1B10. In vitro cell experiments and in vivo animal experiments validated that 1700020I14Rik reduced ethanol-induced hepatocyte damage and inflammation in AH mice through regulation of miR-137–mediated AKR1B10/Erk axis. The current study underlied that 1700020I14Rik could activate AKR1B10/Erk signaling through inhibition of miR-137, thereby promoting the hepatocyte damage in AH mice.

Treatment methods of local residual or recurrent hepatocellular carcinoma (HCC) after thermal ablation are limited. Therefore, our study aimed to explore the efficacy and prognostic factors ofA total of 114 patients with 212 local residual or recurrent HCC tumors after thermal ablation underwentAfter a 6-month follow-up, the percentage of patients who achieved complete response (CR), partial response (PR), and stable disease (SD) was 57%, 13.2%, and 5.2%, respectively. The 1-, 2-, and 3-year LPFS rates were 58.7%, 50.0%, and 41.2%, respectively. Portal vein tumor thrombus (PVTT) (p = 0.03), the number of intrahepatic tumors (p = 0.01), and AFP level (p = 0.02) were independent risk factors for local tumor progression (LTP). The median LPFS in patients without PVTT (22 months) was much longer compared to those with PVTT (10 months). The median LPFS in patients with less than three intrahepatic lesions improved from 17 to 24 months. The median LPFS was only 5 months in the high AFP group, but was prolonged with a decrease in AFP level (24 months). No severe complications were recorded. All complications were controllable and treatable.CT-guided

Mutations in Atp2b2, an outer hair cell (OHC) gene, cause dominant hearing loss (HL) in humans. Using a mouse model Atp2b2Obl+, with a dominant HL mutation (Oblivion), we show that liposome-mediated in vivo delivery of CRISPR-Cas9 ribonucleoprotein (RNP) complexes leads to specific editing of the Obl allele. Large deletions encompassing the Obl locus and indels were identified as the result of editing. In vivo genome editing promotes OHC survival and restores OHC function, leading to robust hearing rescue. We further show in a double-dominant mutant mouse model, in which the Tmc1 Beethoven mutation and the Atp2b2 Oblivion mutation cause di-genic genetic HL, RNP delivery targeting both mutations lead to hearing rescue. These findings suggest that liposome-RNP delivery can be used as a strategy to rescue hearing with dominant mutations in OHC genes and with di-genic mutations in the auditory hair cells, expanding therapeutics of gene editing to treat HL.

Investigations have demonstrated a strong and positive association between dietary intact phospholipid (PL) inclusion and aquatic larval growth, nevertheless, the precise molecular mechanism underlying PL inclusion on growth performance has not been well elucidated. This study aimed to investigate the effects of dietary soybean lecithin (SL) inclusion on growth performance, liver metabolism, resistance to hypoxia stress, and potential molecular mechanisms in rock bream (Oplegnathus fasciatus) larvae. Four types of equal-protein and equal-lipid content microdiets (MDs) were formulated with graded levels of SL to achieve phospholipid levels of (PLs, dry matter) 3.84% (SL0), 6.71% (SL4), 9.38% (SL8), and 12.21% (SL12). Rock bream larvae (25 days post-hatching) were fed the respective MDs for 30 days with three replicates. We found that dietary SL inclusion promoted growth performance, survival rate, and stress resistance to hypoxia stress. The increased dietary SL inclusion improved intestinal structure, as shown by the increased perimeter ratio, muscular thickness, and mucosal fold height of the mid-intestinal tissue. Moreover, a high SL inclusion diet (SL12) increased the activity of the key lipolysis-related enzyme (lipase [LP]) in liver tissue but decreased the activity of amino acid catabolism-related enzymes (aspartate aminotransferase [AST] and alanine aminotransferase [ALT]). RNA sequencing results in liver tissue revealed that the SL12 diet increased the transcriptional level of fatty acid activation-related genes (acsl6 and acsbg2), phospholipid catabolism-related genes (acat2, lpin2, and crls), and amino acid synthesis-related genes (gs, csb, aldh18a1, and oct), but decreased the expression of amino acid catabolism-related gene gprt2. Notably, the SL12 diet significantly increased the expression of ribosome biogenesis-related genes (pes1, nop56, nop58, and rpf2) in liver tissue. The ribosome protein-related pathways were the most enriched pathways mapped in the GO database. Collectively, this study demonstrated the necessity of dietary SL for survival, growth performance, promotion of mid-intestinal morphology, and hypoxia stress during the rock bream larval stage. The SL-induced growth performance promotion was likely attributed to increasing nutrient acquisition by intestinal morphology improvement and to increasing SL catabolism and thereby sparing amino acids for protein synthesis.

Objective. Electrocardiogram (ECG) signals are easily polluted by various noises which are likely to have adverse effects on subsequent interpretations. Research on model lightweighting can promote the practical application of deep learning-based ECG denoising methods in real-time processing. Approach. Firstly, grouped convolution and conventional convolution are combined to replace the continuous conventional convolution in the model, and the depthwise convolution with stride is used to compress the feature map in the encoder modules. Secondly, additional identity connections and a local maximum and minimum enhancement module are designed, which can retain the detailed information and characteristic waveform in the ECG waveform while effectively denoising. Finally, we develop knowledge distillation in the experiments, which further improves the ECG denoising performance without increasing the model complexity. The ground-truth ECG is from The China Physiological Signal Challenge (CPSC) 2018, and the noise signal is from the MIT-BIH Noise Stress Test Database (NSTDB). We evaluate denoising performance using the signal-to-noise ratio (SNR), the root mean square error (RMSE) and the Pearson correlation coefficient (P). We use the floating point of operations (FLOPs) and parameters to calculate computational complexity. Main Results. Different data generation processes are used to conduct experiments: group 1, group 2 and group 3. The results show that the proposed model (U Lde -net) can improve SNRs by 10.30 dB, 12.16 dB and 12.61 dB; reduce RMSEs by 9.88 × 10−2, 20.63 × 10−2 and 15.25 × 10−2; and increase Ps by 14.77 × 10−2, 27.74 × 10−2 and 21.32 × 10−2. Moreover, the denoising performance after knowledge distillation is further improved. The U Lde -net has parameters of 6.9 K and FLOPs of 6.6 M, which are much smaller than the compared models. Significance. We designed a lightweight model, but also retain adequate ECG denoising performance. We believe that this method can be successfully applied to practical applications under time or memory limits.

Purpose The main purpose of our study was to evaluate the impact of a decreased proportion of total serum bilirubin after percutaneous transhepatic biliary drainage (PTBD) on survival and to identify prognostic factors associated with survival in patients with malignant obstruction jaundice (MOJ). Methods From July 2010 to February 2021, 269 patients with MOJ were included. Survival time and prognostic factors were analyzed by Kaplan–Meier curves and the Cox model. The cut-off value of a decrease in the proportion of total serum bilirubin level that predicted patient mortality was determined by receiver operating characteristic (ROC) curves. Results The overall median survival time after PTBD was 135 days (min13-max1276 days-95% IC:117–153). The overall survival (OS) improved from 95 days to 243 days when the procedure achieved functional success. Multivariate analysis demonstrated that functionally successful drainage and post-drainage treatment were independent positive prognostic factors, but the total bilirubin after drainage and tumor size were independent negative predictive values. The cut-off value of the proportional decrease in the total serum bilirubin level for predicting the clinical prognosis was 0.44. Conclusions Palliative care after drainage can prolong patient survival and improve their quality of life. A decreased proportion of total serum bilirubin after PTBD could be used to predict the survival prognosis in patients.

Syngas to aromatics (STA) over bifunctional catalysts has attracted much attention in recent years, but the mechanism underlying the formation of aromatics remains controversial. The critical reaction intermediates, carboxylates, were first identified and then confirmed to essentially promote aromatization in the syngas conversion over a ZnCrAlOx&H-ZSM-5 composite catalyst. This study provides evidence that the carboxylates can be formed during the reactions of formate species and olefins. In addition, it is shown that the carboxylates favor the formation of aromatics over H-ZSM-5 even in the presence of H2. A novel mechanism for the formation of aromatics via the generation and transformation of carboxylate intermediates is proposed, and the transformation of carboxylates to aromatics via methyl-2-cyclopenten-1-one (MCPO) intermediates is indeed likely. A better understanding of the formation mechanism of aromatics would help optimize the composite catalyst.

Previous studies using gram-positive and -negative bacteria demonstrated that hydrolysis of silicon nitride (Si3N4) in aqueous suspensions elutes nitrogen and produces gaseous ammonia while buffering pH. According to immunochemistry assays, fluorescence imaging, and in situ Raman spectroscopy, we demonstrate here that the antipathogenic surface chemistry of Si3N4 can be extended to polymethylmethacrylate (PMMA) by compounding it with a minor fraction (~8 vol.%) of Si3N4 particles without any tangible loss in bulk properties. The hydrolytic products, which were eluted from partly exposed Si3N4 particles at the composite surface, exhibited fungicidal action against Candida albicans. Using a specific nitrative stress sensing dye and highly resolved fluorescence micrographs, we observed in situ congestion of peroxynitrite (ONOO−) radicals in the mitochondria of the Candida cells exposed to the PMMA/Si3N4 composite, while these radicals were absent in the mitochondria of identical cells exposed to monolithic PMMA. These in situ observations suggest that the surface chemistry of Si3N4 mimics the antifungal activity of macrophages, which concurrently produce NO radicals and superoxide anions (O2•−) resulting in the formation of candidacidal ONOO−. The fungicidal properties of PMMA/Si3N4 composites could be used in dental appliances to inhibit the uncontrolled growth of Candida albicans and ensuing candidiasis while being synergic with chemoprophylaxis. Statement of significance In a follow-up of previous studies of gram-positive and gram-negative bacteria, we demonstrate here that the antipathogenic surface chemistry of Si3N4 could be extended to polymethylmethacrylate (PMMA) containing a minor fraction (~8 vol.%) of Si3N4 particles without tangible loss in bulk properties. Hydrolytic products eluted from Si3N4 particles at the composite surface exhibited fungicidal action against Candida albicans. Highly resolved fluorescence microscopy revealed congestion of peroxynitrite (ONOO−) radicals in the mitochondria of the Candida cells exposed to the PMMA/Si3N4 composite, while radicals were absent in the mitochondria of identical cells exposed to monolithic PMMA. The fungicidal properties of PMMA/Si3N4 composites could be used in dental appliances to inhibit uncontrolled growth of Candida albicans and ensuing candidiasis in synergy with chemoprophylaxis.

Acetone is currently produced by large amount of propylene and benzene, and its synthesis from a cheap and non-petroleum material has not yet been reported. Here, we present a new method for acetone production, which involves the carbonylation of dimethyl ether (DME) to methyl acetate and its subsequent ketonization to acetone over pyridine-modified H-mordenite. This convenient approach offers an acetone selectivity of 73% (CO2 excluded) and a DME conversion of 100% at 553 K. Spectral and isotopic studies revealed that the ketonization of methyl acetate was promoted by carbonylation, while the formation of a ketene intermediate was demonstrated by the formation of CH2DCOOD and two types of pyrones. A ketene-based ketonization mechanism was also proposed based on the kinetic isotope effect of CH2=13C O, indicating that the acetyl moiety contributed to the acyl part of acetone, while the ketene moiety was responsible for the alkyl part of acetone and the generation of CO2.

Decarbonylation of carboxylic acids is an effective reaction for alkene production but suffers from the requirement of homogeneous transitional-metal-based catalyst, ligand, and stoichiometric addi...

Metal-modified H-ZSM-5 has a high selectivity of aromatics in methanol to aromatics (MTA) reaction, which is often attributed to the metal promoting the aromatization of intermediate olefins. However, the effect of methanol dehydrogenation on aromatics formation over these catalysts is rarely studied. Here, we report that HCHO, which is formed by methanol dehydrogenation over Zn/H-ZSM-5 prepared by Zn impregnation, can participate in the synthesis of aromatics. Methanol conversion can produce more aromatics than olefins (propylene or ethylene) conversion over Zn/H-ZSM-5, indicating the conventional MTA pathway including methanol-to-olefins and olefins-to-aromatics is not complete. Moreover, an MTA mechanism including the conventional pathway and the methanol and HCHO coupling pathway is systematically proposed.

Direct converting carbon dioxide into hydrocarbon fuels and value-added chemicals would offer a very attractive approach for efficient utilization of CO2 as a carbon resource. Although, olefins, aromatics and gasoline have been successfully synthesized by CO2 hydrogenation, highly selective conversion of CO2 and H2 into C2+ hydrocarbon is still challenging due to a high C–C coupling barrier and inhibiting the production of other long-chain hydrocarbons. Here, we report a composite catalyst made of InZrOx and SSZ-13 molecular sieve (InZrOx + SSZ-13), which exhibits 74.5% propane selectivity at 623 K. The 8-MR micropores and the higher strength of the acid for SSZ-13 benefit the formation of propane. Compared with pure InOx and m-ZrO2, the composite oxide InZrOx containing more oxygen vacancies, exhibits to be more readily reduced by H2 and easier to adsorb and desorb CO2 within the reaction temperature. All those could be beneficial to the activation and conversion of H2 and CO2. The catalytic performance of InZrOx + SSZ-13 in CO2 hydrogenation provides a potential for production of propane.

In this paper, the piezospectroscopic effect for β-Ga2O3, i.e. the spectral band shift in response to strain/stress, has been calibrated by the indentation method using spatially resolved Raman spectroscopy for quantitative stress evaluation of Ga2O3 devices, taking advantage of the crack-tip tensile stress field and the spatial probe deconvolution. A series of Vickers indentation prints were introduced on (010) and ( 2 ˉ 01 ) Ga2O3 single crystals, and the relationships between observed band shifts and residual stresses were clarified to determine the phonon deformation potentials of the Raman bands. Accordingly, a quantitative analysis of the residual stress field in a Ga2O3 thin film grown on (0001) sapphire by plasma-assisted pulsed laser deposition, which revealed the presence of a gradient of incompletely released stress in the depth direction of the film, is shown as an example.

In order to realize the high-precision variable direction cable control of the electro-optical unmanned system in non-electromagnetic remote control, a cable traction device measurement and control with characteristics of variable direction traction, rapid installation, and lightweight portability were proposed. Fan-shaped connect rod mechanism and U-shaped groove fixed pulley group were added to it, which can realize multi-direction traction without derailment on the basis of the cable limit and alleviate the cable fracture caused by mechanical wear. Introducing Euler transformation and analyzing the dynamics of the cable, the whole operation process, and the tension detection model was established. A Kalman Filter traction planning method was proposed to solve the problems of inertia delay and emergency stop of the unmanned vehicles after a sudden direction change. In order to verify the effectiveness, an experimental platform for the cable traction system of a 50kg wheeled and 150kg tracked unmanned system was built for simulation and experimental testing. The results show that the cable system has good dynamic variable traction, which can meet the multi-terrain control ability of an electro-optical unmanned system in a complex field environment.

One of the greatest triumph of condensed matter physics in the past ten years is the classification of materials by the principle of topology. The existence of topological protected dissipationless surface state makes topological insulators great potential for applications and hotly studied. However, compared with the prosperity of strong topological insulators, theoretical predicted candidate materials and experimental confirmation of weak topological insulators (WTIs) are both extremely rare. By combining systematic first-principles calculation and angle-resolved photoemission spectroscopy measurements, we have studied the electronic structure of the dark surface of the WTI candidate Zintl Ba3Cd2Sb4 and another related material Ba3Cd2As4. The existence of two Dirac surface states on specific side surfaces predicted by theoretical calculations and the observed two band inversions in the Brillouin zone give strong evidence to prove that the Ba3Cd2Sb4 is a WTI. The spectroscopic characterization of this Zintl Ba3Cd2N4 (N = As and Sb) family materials will facilitate applications of their novel topological properties.

Purpose The purpose of this paper is to develop an improved adhesion model to better reproduce the low adhesion condition of the anti-skid control for rail vehicles under braking condition. Design/methodology/approach In view of the low adhesion characteristics for rail vehicles under braking conditions, the Polach adhesion model was improved based on the sliding power and sliding energy. The wheel–rail low adhesion model suitable for braking condition was given. The analysis of braking anti-skid control under emergency braking condition was carried out through the co-simulation, and compared with the test data; the effectiveness and practicability of the improved low adhesion model were verified. Findings The results showed that the improved adhesion model is simple and efficient and the parameters involved are less, and it can be directly applied to the real-time simulation of anti-skid control in the process of train braking. Originality/value This paper can provide a theoretical reference for the reasons of change and improvement of adhesion between wheel and rail caused by the adjustment of braking force under anti-skid control, which can fulfill a need to the study of sliding energy on the contact surface, the removal effect of pollutants on the wheel–rail surface and the improvement and recovery of adhesion caused. Peer review The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-07-2020-0244/

Efficient direct transformation of methane into value-added chemicals has great significance for long-term sustainability of fuels and chemicals, but remains a major challenge due to its high inertness. Reported here is that methane can be activated effectively via carbonylation with CO over Zn/HZSM-5 catalysts under mild conditions. The selectivity to aromatics alone reaches 80% among all hydrocarbon products at 823 K, whereas as high as 92% ethane selectivity is achieved at a lower temperature of 673 K. 13CO isotope labelling experiments demonstrate that approximately 50% of the carbon atoms in all the products originate from carbon monoxide, whereas another half of the carbons come from methane, indicating that the precursors of hydrocarbon products are acyl compounds and/or acetic acid formed by carbonylation of methane with carbon monoxide. This provides potential for transformation of methane into value-added chemicals under mild reaction conditions.

Dopant distribution is key to understand sintering behavior and microstructure‒property relationship of silicon carbide (SiC) ceramics. Using high-angle secondary-electron (SE) imaging in scanning electron microscope combining elemental and cathodoluminescence (CL) analysis, core‒rim structures were found as common microstructural features in SiC ceramics sintered with rare-earth oxides. Characteristic emission by donor-accepter-pairs (DAP) could reveal co-solution of Al‒N in α- and β-SiC phases in hot-pressed and gas-pressure sintered ceramics, with or without AlN co-dopant. Stacking-faults (SFs) were found in β-SiC grains to emit characteristic photons by local twin-structures, which confine the luminous transition by DAP into a quantum effect and suppress fully the luminescence when SF density reaches a limit by sintering with two rare-earth oxides. Systematic correlation between the development of microstructures, solution and defect luminescence, and phase transformation can lead to hierarchical microstructure‒property relationship to study synergetic mechanical, thermal and opto-electrical performance of SiC ceramics as well as electronic materials.

The multidrug-resistant Candida auris often defies treatments and presently represents a worldwide public health threat. Currently, the ergosterol-targeting Amphotericin B (AmB) and the DNA/RNA-synthesis inhibitor 5-flucytosine (5-FC) are the two main drugs available for first-line defense against life-threatening Candida auris infections. However, important aspects of their mechanisms of action require further clarification, especially regarding metabolic reactions of yeast cells. Here, we applied Raman spectroscopy empowered with specifically tailored machine-learning algorithms to monitor and to image in situ the susceptibility of two Candida auris clades to different antifungal drugs (LSEM 0643 or JCM15448T, belonging to the East Asian Clade II; and, LSEM 3673 belonging to the South African Clade III). Raman characterizations provided new details on the mechanisms of action against Candida auris Clades II and III, while also unfolding differences in their metabolic reactions to different drugs. AmB treatment induced biofilm formation in both clades, but the formed biofilms showed different structures: a dense and continuous biofilm structure in Clade II, and an extra-cellular matrix with a “fluffy” and discontinuous structure in Clade III. Treatment with 5-FC caused no biofilm formation but yeast-to-hyphal or pseudo-hyphal morphogenesis in both clades. Clade III showed a superior capacity in reducing membrane permeability to the drug through chemically tailoring chitin structure with a high degree of acetylation and fatty acids networks with significantly elongated chains. This study shows the suitability of the in situ Raman method in characterizing susceptibility and stress response of different C. auris clades to antifungal drugs, thus opening a path to identifying novel clinical solutions counteracting the spread of these alarming pathogens.