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Abstract Electrocatalytic water splitting seems to be an efficient strategy to deal with increasingly serious environmental problems and energy crises but still suffers from the lack of stable and efficient electrocatalysts. Designing practical electrocatalysts by introducing defect engineering, such as hybrid structure, surface vacancies, functional modification, and structural distortions, is proven to be a dependable solution for fabricating electrocatalysts with high catalytic activities, robust stability, and good practicability. This review is an overview of some relevant reports about the effects of defect engineering on the electrocatalytic water splitting performance of electrocatalysts. In detail, the types of defects, the preparation and characterization methods, and catalytic performances of electrocatalysts are presented, emphasizing the effects of the introduced defects on the electronic structures of electrocatalysts and the optimization of the intermediates' adsorption energy throughout the review. Finally, the existing challenges and personal perspectives of possible strategies for enhancing the catalytic performances of electrocatalysts are proposed. An in‐depth understanding of the effects of defect engineering on the catalytic performance of electrocatalysts will light the way to design high‐efficiency electrocatalysts for water splitting and other possible applications.

The freeze–thaw effect has a significant impact on the strength deterioration of tunnel-lining concrete in cold regions. Therefore, the strength deterioration characteristics of concrete in a tunnel were studied, and silicone coating materials were used to improve its frost resistance and durability under freeze–thaw cycles. Freeze–thaw cycle tests were conducted on concrete specimens with different coatings. The freeze–thaw damage phenomenon, dynamic elastic modulus, and mass loss of the specimens were used to evaluate the freeze–thaw durability of concrete strengthened with coatings. The results demonstrated that silicone coatings effectively prevented moisture and corrosive substances from infiltrating the concrete, thereby enhancing its durability; the silicone–polyether hybrid had the most significant frost resistance at 500 g/m2 and silane type III at 300 g/m2, with freezing resistance times of 175 and 300, respectively. During the freeze–thaw process, the strength reduction rate of specimens was much greater than the mass loss rate of concrete. Taking into account the water environment surrounding the lining concrete and the site temperature, an equivalent indoor freeze–thaw cycle conversion model was established. The results can provide an experimental basis for selecting better frost-resistant materials for tunnel concrete in cold regions.

Sisal purple leafroll disease (SPLD) is a destructive disease affecting sisal in China, however, its etiology remains unknown. This disease is characterized by purple margins and rolling and yellowing of the leaves. Recently, phytoplasma was found to be present in SPLD-affected sisal according to PCR assay. To further verify the presence of phytoplasma, determine its association with SPLD and identify the possible pathogenic phytoplasma infecting sisal, 80 symptomatic and 65 asymptomatic sisal samples were collected from the main sisal farms in three Chinese provinces, including Hainan, Guangdong and Guangxi provinces, from 2018 to 2021. PCR assays and transmission electron microscopy further revealed the presence of phytoplasma. Nested PCR using the universal primer R16mF2/R16mR1 followed by R16F2n/R16R2 was confirmed as the most effective molecular method for the detection of phytoplasma in sisal. A comparison of the detection rate of phytoplasma in symptomatic (83%) versus asymptomatic (17%) sisal populations showed some association between phytoplasma and SPLD. Sequencing analyses, phylogenetic analyses, and virtual restriction fragment length polymorphism analyses confirmed the presence of phytoplasma in sisal belonging to 16SrI-B. This is the first report of 16SrI-B phytoplasma infecting sisal in China.

Dissolved organic matter (DOM) is an important part of the material cycle in the water environment, and it plays an important role in the nutrient cycle of nitrogen and phosphorus in eutrophic water and biological processes. Dianchi Lake is a heavily eutrophic plateau lake in China. To investigate the fluorescence characteristics of DOM and the influences of DOM on water quality of rivers and lakes in the Dianchi Lake basin, three-dimensional fluorescence spectroscopy and high-resolution mass spectrometry were employed to determine the features of dissolved organic matter (DOM) components. According to the research results, the DOM components in rivers and lakes in the Dianchi Lake basin were dominated by humic-like substances and affected by seasonal changes to a certain extent. DOM in Dianchi Lake is affected by the macrophytes and algae distribution as well as inflowing rivers, but the dominant factors are different in dry and rainy seasons. PCA results indicated that DOM components had relatively high relevance to water quality indicators, especially COD and TN. In conclusion, Lake ecosystem status and pollution levels can be characterized by DOM to some extent, the DOM components in the Dianchi Lake are prone to humification with the implementation of wastewater treatment and aquatic ecological restoration projects, as reflected in the improved water quality index.

ObjectivesSpread through air spaces (STAS), a new invasive pattern in lung adenocarcinoma (LUAD), is a risk factor for poor outcome in early-stage LUAD. This study aimed to develop and validate a CT-based radiomics model for predicting STAS in stage IA LUAD.MethodsA total of 395 patients (169 STAS positive and 226 STAS negative cases, including 316 and 79 patients in the training and test sets, respectively) with stage IA LUAD before surgery were retrospectively included. On all CT images, tumor size, types of nodules (solid, mix ground-glass opacities [mGGO] and pure GGO [pGGO]), and GGO percentage were recorded. Region of interest (ROI) segmentation was performed semi-automatically, and 1,037 radiomics features were extracted from every segmented lesion. Intraclass correlation coefficients (ICCs), Pearson’s correlation analysis and least absolute shrinkage and selection operator (LASSO) penalized logistic regression were used to filter unstable (ICC < 0.75) and redundant features (r > 0.8). A temporary model was established by multivariable logistic regression (LR) analysis based on selected radiomics features. Then, seven radiomics features contributing the most were selected for establishing the radiomics model. We then built two predictive models (clinical-CT model and MixModel) based on clinical and CT features only, and the combination of clinical-CT and Rad-score, respectively. The performances of these three models were assessed.ResultsThe radiomics model achieved good performance with an area under of curve (AUC) of 0.812 in the training set, versus 0.850 in the test set. Furthermore, compared with the clinical-CT model, both radiomics model and MixModel showed higher AUC and better net benefit to patients in the training and test cohorts.ConclusionThe CT-based radiomics model showed satisfying diagnostic performance in early-stage LUAD for preoperatively predicting STAS, with superiority over the clinical-CT model.

Abstract Background Psychological investigations and functional imaging technology have been used to describe neural correlations of different types of memory with various stimuli. Memory with limited storage capacity and a short retention time can be classified as short-term memory (STM) while long-term memory (LTM) can be life-long without defined capacity. Methods To identify brain activation pattern associated with different modes of memory for numerical figures, we detected brain activities from twenty-two healthy subjects when performing three types of memory tasks for numbers, namely STM, LTM and working memory (WM), by using functional magnetic resonance imaging (fMRI) technique. Results The result revealed variable patterns of activation in different brain regions responding to different types of memory tasks. The activation regions with primary processing and transient maintenance of STM for numerical figures are located in the visual cortex and mainly encoded by visual representations, while LTM was encoded by semantics and mainly recruiting left frontal cortex. We also found that subcortical structures, such as the caudate nucleus and the marginal division of the striatum, plays important roles in working memory. Conclusions Activation of different brain regions in these three kinds of memories, indicating that different kinds of memories rely on different neural correlates and mental processes.

Commuters are reportedly exposed to severe traffic-related air pollution (TRAP) during their commuting trips. This study was designed and implemented to (1) compare particulate matter (PM) exposure across four common transportation modes; (2) examine and analyze various determining factors; and (3) estimate public health effects caused by commuting exposure to PM. All analyses and calculations were based on the experimental data collected from 13 volunteers, including heart-rate data on 336 commuting trips in four travel modes in Xi’an China. The results indicate highest PM exposure associated with cycling (average PM10, PM2.5 and PM1.0 of 114.35, 72.37 and 56.51 μg/m3, respectively), followed by riding transit buses (116.29, 67.60 and 51.12 μg/m3 for the same pollutants, respectively), then taking a taxi (97.61, 58.87 and 45.11 μg/m3), and the lowest exposure onboard subways (55.86, 46.20 and 40.20 μg/m3). A multivariable linear regression model was used to examine major influences on PM concentration variations, with results corroborating significant PM variance across commuting modes, which is also affected by background pollution concentration and relative humidity. Further, years of life expectancy (YLE) loss were estimated using an inhalation dose model together with the life table method: cycling commuters experienced the greatest YLE loss (5.51–6.43 months per capita for the studied age group). During severe pollution periods, substituting other modes (like subway) for cycling could effectively avoid acute exposure. PM2.5 levels in taxi cabins powered by CNG or methanol were comparatively lower, indicating that implementing alternative energy strategies could effectively lower traffic emissions and population exposure.

Ideberg III glenoid fractures are rare and difficult in treating among shoulder fractures. With the development of research, a series of surgical approaches and methods were performed, such as anterior approach, traditional Judet approach, modified Judet approach, combined approach, acromion approach and so on. While these approaches still have some limitations in treatment of Ideberg III glenoid fractures with superior shoulder suspensory complex(SSSC) injury, for extensive soft tissue dissection, unsatisfactory exposure, difficult surgical intervention. In our case with Ideberg III glenoid fracture with acromioclavicular dislocation, superior approach was adopted during treatment of the scapula glenoid fracture and coracoclavicular ligament rupture perfectly. The result was satisfactory in accordance with 92 points by Constant-Murley score. We believe that individualized therapy should depend on the injury types, and superior approach would be a new valuable method for Ideberg III glenoid fractures with SSSC injury.

Asparagus stem wilt, is a significant and devastating disease, typically leading to extensive economic losses in the asparagus industry. To obtain transgenic plants resistant to stem wilt, the hevein-like gene, providing broad spectrum bacterial resistance was inserted into the asparagus genome through Agrobacterium tumefaciens-mediated transformation. The optimal genetic transformation system for asparagus was as follows: pre-culture of embryos for 2 days, inoculation using a bacterial titre of OD600 = 0.6, infection time 10 min and co-culturing for 4 days using an Acetosyringone concentration of 200 μmol/L. Highest transformation frequencies reached 21% and ten transgenic asparagus seedlings carrying the hevein-like gene were identified by polymerase chain reaction. Moreover, integration of the hevein-like gene in the T1 generation of transgenic plants was confirmed by southern blot hybridization. Analysis showed that resistance to stem wilt was enhanced significantly in the transgenic plants, in comparison to non- transgenic plants. The results provide additional data for genetic improvement and are of importance for the development of new disease-resistant asparagus varieties.

Background:Plutella xylostella has become a notorious pest of cruciferous crops all over the world. Delta-endotoxins of Bacillus thuringiensis are widely used insecticidal proteins for controlling P. xylostella. However, the interaction mechanism of B. thuringiensis with the immune system of P. xylostella, at the genomic level, is still unclear. This study explored the immune response of P. xylostella to B. thuringiensis, at different time intervals, 6 h, 12 h, 18 h, 24 h, and 36 h, by using RNA-Sequencing (RNA-Seq) and RT-qPCR.Results: In total, 167 immunity-related genes were identified and placed into different families, including pattern recognition receptors (PRRs), signal modulators, immune pathways (Toll, IMD, and JAK/STAT), and immune effectors. It is worth mentioning that the analyses of the differentially expressed immunity-related genes revealed that most of the differentially expressed genes (DEGs) (87, 56, 76, 67, and 73 genes) were downregulated in P. xylostella following B. thuringiensis oral infection at 6 h, 12 h, 18 h, 24 h, and 36 h. Interestingly, our RNA-Seq analysis also revealed reduced expression of antimicrobial peptides, that play a vital role in the humoral immune system of P. xylostella.Conclusion: This study demonstrates that B. thuringiensis plays a novel role in controlling P. xylostella, by suppressing the immune system.

Agave species are an important family of crassulacean acid metabolism (CAM) plants with remarkable tolerance to heat and drought stresses (Agave deserti) in arid regions and multiple agricultural applications, such as spirit (Agave tequilana) and fiber (Agave sisalana) production. The agave genomes are commonly too large to sequence, which has significantly restricted our understanding to the molecular basis of stress tolerance and economic traits in agaves. In this study, we collected three transcriptome databases for comparison to reveal the phylogenic relationships and evolution patterns of the three agave species. The results indicated the close but distinctly domesticated relations between A. tequilana and A. sisalana. Natural abiotic and biotic selections are very important factors that have contributed to distinct economic traits in agave domestication together with artificial selection. Besides, a series of candidate unigenes regulating fructan, fiber, and stress response-related traits were identified in A. tequilana, A. sisalana, and A. deserti, respectively. This study represents the first transcriptome comparison within domesticated and wild agaves, which would serve as a guidance for further studies on agave evolution, environmental adaptation, and improvement of economically important traits.

Stylosanthes sp. is the most important forage legume in tropical areas worldwide. Stylosanthes anthracnose, which is mainly caused by Colletotrichum gloeosporioides, is a globally severe disease in stylo production. Little progress has been made in anthracnose molecular pathogenesis research. In this study, Agrobacterium tumefaciens-mediated transformation was used to transform Stylosanthes colletotrichum strain CH008. The major factors of the genetic transformation system of S. colletotrichum were optimized as follows: A. tumefaciens' AGL-1 concentration (OD(600)), 0.8; concentration of Colletotrichum conidium, 1 × 10(6) conidia/mL; acetosyringone concentration, 100 mmol/L; induction time, 6 h; co-culture temperature, 25 °C; and co-culture time, 3 d. Thus, the transformation efficiency was increased to 300-400 transformants per 106 conidia. Based on the optimized system, a mutant library containing 4616 mutants was constructed, from which some mutants were randomly selected for analysis. Results show that the mutants were single copies that could be stably inherited. The growth rate, spore amount, spore germination rate, and appressorium formation rate in some mutants were significantly different from those in the wild-type strain. We then selected the most appropriate method for the preliminary screening and re-screening of each mutant's pathogenic defects. We selected 1230 transformants, and obtained 23 strains with pathogenic defects, namely, 18 strains with reduced pathogenicity and five strains with lost pathogenicity. Thermal asymmetric interlaced PCR was used to identify the transfer DNA (T-DNA) integration site in the mutant that was coded 2430, and a sequence of 476 bp was obtained. The flanking sequence of T-DNA was compared with the Colletotrichum genome by BLAST, and a sequence of 401 bp was found in Contig464 of the Colletotrichum genome. By predicting the function of the flanking sequence, we discovered that T-DNA insertion in the promoter region of the putative gene had 79% homology with the aspartate aminotransferase gene in Magnaporthe oryzae (XP_003719674.1).

The mechanical properties of the rotary drilling system are analyzed in depth and the complex mechanical behaviors of integral tubular strings and the effects of joints are studied. The results show that before the mechanical calculation of the drilling string, the inversion of the friction coefficient by the near-well data can improve the calculation accuracy of the friction and torque of the string. Rotating casing can ensure smooth running in the extended well. The injection of light medium can alleviate the axial force, but it is not enough to ensure safe running, which needs to be combined with the rotating casing method. By increasing the rotation per minute and reducing the weight on bit, the buckle of drill string can be avoided. [ABSTRACT FROM AUTHOR]