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The disposal of agricultural waste ash is a great ecological challenge. This study analyzed the basic properties of corn straw ash and soybean straw ash, encompassing the identification of key oxides, the assessment of particle size distribution, and the performance of thermogravimetric analysis. This study also evaluated the potential of corn straw ash and soybean straw ash to replace cement in mortar and concrete through laboratory tests. The findings indicated that the strength activity index of corn straw ash was higher than soybean straw ash. Furthermore, when these ashes were used as cement replacements, the compressive strength of concrete decreased. Notably, concrete containing corn straw ash exhibited greater strength than concrete with the same substitution amount of soybean straw ash. Specifically, at a 5% substitution level, the compressive strengths of corn straw ash concrete and soybean straw ash concrete were 31.5 and 30.5 MPa, respectively. Additionally, soybean straw ash concrete demonstrated superior resistance to water penetration compared to corn straw ash concrete. Both corn straw ash and soybean straw ash exhibited the potential to enhance the early crack resistance of concrete.

Subway tunneling construction in shallow buried karst region is a common challenge. Survey boreholes and cross-hole seismic CT data showed that 29 karst caves exist at elevation of −17 m to −37 m in Si–He section of the Wuxi Metro Line 4, which are consisted of 18 filled caves and 11 empty caves and constitute substantial dangers to the stability and quality of metro construction projects. Based on their size, position, and type of filling, we divided these shallow karst caves into four types. Aimed at exploring the instability of the tunnel after excavation, numerical analyses have been developed by using the Finite difference method. Both the effects of the distance between tunnel and karst caves and the effects of the filling of the cavities on the overall stability of the rock mass around the tunnel have been investigated. According to the design criteria, safety distance between tunnel and karst caves was determined. The monitoring data of tunnel during excavation proved the rationality and accuracy of the analysis results. The research results can provide technical reference for the design and construction of other proposed tunnels that are located in the regions of shallow buried karst in Jiangsu Province.

China has abundant straw resources; however, the utilization of straw waste resource remains challenging. In this work, corn straw fiber and corn straw ash were applied to concrete as raw material after pretreatment. Through mechanical and thermal conductivity tests, it was concluded that the tensile strength of the corn straw fiber was 160.5 MPa after alkali treatment. The corn straw fiber and corn straw powder did not enhance the compressive strength of concrete. Compared with original concrete, the thermal conductivity of concrete added with 1.5% corn straw powder decreased by 25.9%, and the thermal conductivity of concrete with 5% corn straw ash was reduced by only 5.2%. Through thermogravimetric analysis of the concrete, it was found that the internal weakly bound water and strongly bound water will be lost in the range 100 °C to 160 °C, Ca(OH)2 will decompose from 420 °C to 500 °C, and CaCO3 will decompose approximately at 800 °C. It is recommended that corn straw powder and corn straw ash can be added at 1.5% and 5% concentrations to ensure that the mechanical properties can meet the engineering requirements and achieve good insulation performance. [ABSTRACT FROM AUTHOR]

Abstract Background Describing the transmission dynamics of infectious diseases across different regions is crucial for effective disease surveillance. The multivariate time series (MTS) model has been widely adopted for constructing cross-regional infectious disease transmission networks due to its strengths in interpretability and predictive performance. Nevertheless, the assumption of constant parameters frequently disregards the dynamic shifts in disease transmission rates, thereby compromising the accuracy of early warnings. This study investigated the applicability of time-varying MTS models in multi-regional infectious disease monitoring and explored strategies for model selection. Methods This study focused on two prominent time-varying MTS models: the time-varying parameter-stochastic volatility-vector autoregression (TVP-SV-VAR) model and the time-varying VAR model using the generalized additive framework (tvvarGAM), and intended to explore and verify their applicable conditions for the surveillance of infectious diseases. For the first time, this study proposed the time delay coefficient and spatial sparsity indicators for model selection. These indicators quantify the temporal lags and spatial distribution of infectious disease data, respectively. Simulation study adopted from real-world infectious disease surveillance was carried out to compare model performances under various scenarios of spatio-temporal variation as well as random volatility. Meanwhile, we illustrated how the modelling process could help the surveillance of infectious diseases with an application to the influenza-like case in Sichuan Province, China. Results When the spatio-temporal variation was small (time delay coefficient: 0.1–0.2, spatial sparsity:0.1–0.3), the TVP-SV-VAR model was superior with smaller fitting residuals and standard errors of parameter estimation than those of the tvvarGAM model. In contrast, the tvvarGAM model was preferable when the spatio-temporal variation increased (time delay coefficient: 0.2–0.3, spatial sparsity: 0.6–0.9). Conclusion This study emphasized the importance of considering spatio-temporal variations when selecting appropriate models for infectious disease surveillance. By incorporating our novel indicators—the time delay coefficient and spatial sparsity—into the model selection process, the study could enhance the accuracy and effectiveness of infectious disease monitoring efforts. This approach was not only valuable in the context of this study, but also has broader implications for improving time-varying MTS analyses in various applications.

Abstract Novel phase of nano materials that break the traditional structural constraints are highly desirable, particularly in the field of mechanocatalysis, offering versatile applications ranging from energy to medical diagnosis and treatment. In this work, a distinct layered barium dititanate (BaTi2O5) nanocrystals using a pH‐modulated hydrothermal method is successfully synthesized. These nanocrystals exhibit outstanding hydrogen generation capability (1160 µmol g−1 h−1 in pure water) and demonstrate remarkable performance in organic dye degradation using ultrasonication. The crystal structure of this newly discovered BaTi2O5 phase, is determined by a combination of synchrotron Powder Diffraction refinement and X‐ray adsorption techniques, including X‐ray Absorption Near Edge Structure (XANES) and Extended X‐ray Absorption Fine Structure (EXAFS). Density Functional Theory calculations revealed that the newly‐discovered BaTi2O5 phase demonstrates dipole moments along the z‐axis, distributed in an antiparallel direction within a single unit cell. These inherent dipoles induce a surface polarization and a ferroelectric‐flexoelectric response under mechanical stimuli when the materials go to nano dimension. With a band alignment well‐suitable for hydrogen and reactive oxygen species generation, this BaTi2O5 phase demonstrates promising potential for Mechanocatalysis. The discovery of this distinct phase not only enriches the material candidates for mechanocatalysis but also provides valuable insights.

Abstract Background There is a significant increase in the number of SARS-CoV-2 reinfection reports in various countries. However, the trend of reinfection rate over time is not clear. Methods We searched PubMed, Web of Science, Medline, Embase, Cochrane Central Register of Controlled Trials, China National Knowledge Infrastructure, and Wanfang for cohort studies, case-control studies, and cross-sectional studies up to March 16, 2023, to conduct a meta-analysis of global SARS-CoV-2 reinfection rate. Subgroup analyses were performed for age, country, study type, and study population, and time-varying reinfection rates of SARS-CoV-2 were estimated using meta-regression. The risk of bias was assessed using the Newcastle-Ottawa Scale and the Joanna Briggs Institute critical appraisal tool. Result A total of 55 studies involving 111,846 cases of SARS-CoV-2 reinfection were included. The pooled SARS-CoV-2 reinfection rate was 0.94% (95% CI: 0.65 -1.35%). In the subgroup analyses, there were statistically significant differences in the pooled reinfection rates by reinfection variant, and study type (P

BiFeO3 (BFO), Mn-doped-BFO (BFMO), Ti-doped-BFO (BFTO), and (Mn,Ti)-codoped-BFO (BFMTO) thin films are fabricated on the Pt/TiO2/SiO2/Si substrates via a sol–gel method combined with spin-coating and the subsequent layer-by-layer annealing technique. Compared with BFO film, the BFMTO film exhibits the lowest leakage current density ([Formula: see text][Formula: see text]A/cm2@290[Formula: see text]kV/cm). Notably, the polarization–electric field (P–E) loop of BFMTO film exhibits a positive displacement along the x-axis due to the existence of internal bias electric field, which is in agreement with the results of the PFM phase and amplitude curves. Especially, a very prominent inverse piezoelectric constant of [Formula: see text][Formula: see text]pm/V was obtained, which overcomes other related thin films. The internal bias electric field of BFMTO film can be caused by the different work functions of the thin film and the bottom electrode, accumulation of oxygen vacancies and the formation of defect dipoles. Besides, the internal bias electric field of BFMTO film has a good stability at the same electric field after experiencing the test cycle from low electric field to high electric field (400–1900[Formula: see text]kV/cm). These results indicate that self-polarized BFMTO film can be integrated to devices without additional polarization process, and have a wide range of application in microelectromechanical systems.

BackgroundMultiple investigations and scholarly articles have presented compelling evidence indicating that tertiary lymphoid structures (TLS) play a pivotal role in inhibiting and controlling the advancement of tumors. While there is an abundance of information highlighting the importance of TLS in different cancer types, their prognostic significance specifically in hepatocellular carcinoma (HCC) cancers remains unclear. Thus, this meta-analysis aimed to explore the prognostic relevance of TLS in HCC.MethodsWe conducted a thorough search across four databases, namely Web of Science, PubMed, Embase, and the Cochrane Library, to identify pertinent studies. The search utilized the keywords “tertiary lymphoid structures” and “hepatocellular carcinoma.” The primary outcomes of interest encompassed overall survival (OS), recurrence-free survival (RFS), early recurrence, and late recurrence. The statistical effect size for these measures was expressed in terms of hazard ratios (HR).ResultsSix studies were incorporated into the analysis. Among them, four studies, encompassing 6 datasets and involving 1490 patients, and three studies, comprising 5 datasets and involving 656 patients, respectively, investigated the correlation between intratumoral and peritumoral TLSs and the prognosis in HCC patients. The meta-analysis revealed that the presence of intratumoral TLSs is linked to longer RFS and reduced early recurrence (HR, 0.60; 95% CI, 0.50–0.67; p

Abstract Background The role of mitochondrial dynamics, encompassing fission, fusion, and mitophagy, in cancer progression has been extensively studied. However, the specific impact of mitochondrial dynamics on hepatocellular carcinoma (HCC) is still under investigation. Methods In this study, mitochondrial dynamic genes were obtained from the MitoCarta 3.0 database, and gene expression data were collected from The Cancer Genome Atlas (TCGA) database. Based on the expression of these dynamic genes and differentially expressed genes (DEGs), patients were stratified into two clusters. Subsequently, a prognostic model was constructed using univariate COX regression and the least absolute shrinkage and selection operator (LASSO) regression, and the prognostic signature was evaluated. We analyzed the interaction between these model genes and dynamic genes to identify hub genes and reveal mitochondrial status. Furthermore, we assessed immune infiltration, tumor mutational burden (TMB), tumor stemness indices (TSI), and the response to immune checkpoint block (ICB) therapy using the TIDE algorithm and risk scores. Additionally, transmission electron microscopy (TEM), hematoxylin-eosin (H&E) staining, immunohistochemistry (IHC), western blotting (WB), and immunofluorescence (IF) were conducted to afford detailed visualization of the morphology of the mitochondria and the expression patterns of fission-associated proteins. Results Patients in Cluster 2 exhibited heightened mitochondrial fission and had a worse prognosis. The up-regulated dynamic genes in Cluster 2 were identified as fission genes. GO/KEGG analyses reconfirmed the connection of Cluster 2 to augmented mitochondrial fission activities. Subsequently, a ten-gene prognostic signature based on the differentially expressed genes between the two clusters was generated, with all ten genes being up-regulated in the high-risk group. Moreover, the potential links between these ten signature genes and mitochondrial dynamics were explored, suggesting their involvement in mediating mitochondrial fission through interaction with MTFR2. Further investigation revealed that the high-risk group had an unfavorable prognosis, with a higher mutation frequency of TP53, increased immune checkpoint expression, a higher TIS score, and a lower TIDE score. The mitochondrial imbalance characterized by increased fission and upregulated MTFR2 and DNM1L expression was substantiated in both HCC specimens and cell lines. Conclusions In conclusion, we developed a novel MTFR2-related prognostic signature comprising ten mitochondrial dynamics genes. These genes play crucial roles in mitochondrial fission and have the potential to serve as important predictors and therapeutic targets for HCC.

With the rapid development of modern industries, the high-temperature piezoelectric sensors that can work in extreme environments are in great demand. In this work, langasite (La3Ga5SiO[Formula: see text], LGS), as a high-temperature piezoelectric crystal with stable electro-elastic performance, is used as core element, and air and porous Al2O3 are selected as backing layers respectively to prepare two kinds of high-temperature acoustic emission (AE) sensors. The detection sensitivities at 25–500∘C are analyzed by the ball falling test and Hsu–Nielsen experiment. Under the condition of 25–500∘C, the received amplitude signals by both sensors are maintained above 90[Formula: see text]dB stimulated by the ZrO2 ceramic ball dropping. In the Hsu–Nielsen experiment, as the temperature rising from 25∘C to 500∘C, the signal amplitude of sensor with air backing layer decays from 447[Formula: see text]mV to 365[Formula: see text]mV, while the signal amplitude varies from 270[Formula: see text]mV to 203[Formula: see text]mV for the sensor with porous Al2O3 backing layer. Significantly, compared with the bandwidth of the air-backing sensor (37–183[Formula: see text]kHz), the sensor with porous Al2O3 backing layer broadens bandwidth to 28–273[Formula: see text]kHz. These results show that both these AE sensors have strong and stable response ability to AE signals at high-temperature of 500∘C. Therefore, piezoelectric AE sensor based on LGS has great potential application in the field of high-temperature structural health monitoring.