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Volunteer teaching is an important measure to support the development of rural education. Narrative research is a method of explaining the volunteer teachers' behavior and its significance. As the most important resource of rural education, volunteer teachers have played an important role in consolidating and expanding the achievements of poverty alleviation and blocking the transmission of poverty between generations. As a component of volunteer teachers in rural schools, graduate student assistance teaching groups have their unique characteristics compared with other types of volunteer teachers. In taking root in rural society and serving rural education, they bear the dual role of "teaching" the students in poverty-stricken areas, as well as "being taught" in teaching practices. From the education practice of "being a teacher" to poverty alleviation thinking of "dual support of aspiration and knowledge", then to the deep interaction between teaching and learning of "teaching is also being taught", a benign interaction mode of education assistance and teacher growth has been formed among them. In the effective connection between consolidating and expanding the achievements of poverty alleviation and accelerating the comprehensive of rural revitalization, it is necessary to continuously improve the support mechanism of graduate student assistance teaching groups from both internal and external aspects, so as to better leverage the power of volunteer teaching.

Objective The Laiwu Basin is a typical monocline fault basin in the central and southern regions of Shandong Province. It has a complex geological structure and an uneven distribution of groundwater resources within the region. Previous researchers have conducted a large number of hydrogeological and spring water protection studies, but no relevant research has been conducted on the relationship between the development laws of fissure karst and the distribution of karst groundwater. Methods In this study, karstification and groundwater enrichment characteristics were investigated in the Laiwu Basin through research methods of data collection, field geological surveys, hydrogeological drilling, and rock and mineral testing. Results Carbonate strata are concentrated in the southern part of the Laiwu Basin, with a monoclinal structure controlled by the geological structure, which is scattered sporadically in the northern and eastern regions. Karst development is affected by many factors, such as formation lithology, geological structure, groundwater dynamic conditions, and magma intrusion. The principal surface karst features are grikes and karst valleys. In addition, the principal underground karst features were dominated by dissolution fissures and holes at 400 m depth. Karst groundwater is primarily concentrated in multistage structural fault basins, hanging walls formed by water-blocking faults, groundwater pressure discharge areas, and karst development areas on the anticlinal flank of the mine. Conclusion The karst water cycle in the Laiwu Basin has a general regularity of monoclinic basins but is influenced by multiple factors, forming karst water systems of varying sizes that are relatively independent. Significant differences were observed in the development characteristics and water abundance patterns of karsts in different regions. Fault structures and geological water-blocking areas have relatively abundant karst water, whereas the shallow karst water has a strong runoff cycle. [ Significance ] This study provides scientific and technical support for the exploitation and utilization of groundwater resources in water-scarce mountainous areas of central and southern Shandong Province.

【Objective】 The Shendong mining region is the largest coal mine in China. Extensive coal mining for many years has altered the geological landscape and disrupted ecology, leading to surface subsidence, drop of groundwater table, loss of soil moisture and nutrients, and landscape fragmentation in the region. This paper is to investigate the spatial variability in drought and its correlation to coal mining-induced collapses in the region. 【Method】 The analysis is based on temperature vegetation drought index (TVDI), and surface droughts measured from 2002 to 2018. Spatial variations in environmental factors and their effect on drought are analyzed using a geographical detector model by elucidating the response of drought to coal mining. 【Result】 TVDI had been consistently decreasing from 2002 to 2018, reaching the lowest point at 0.561 in 2018. Temporarily, May to August saw the most severe drought each year. Spatially, the southwest experienced higher drought severity than the northeast. The q-values obtained from the geographic detector analysis for precipitation, normalized vegetation index (NDVI), and soil type excepted 10% each year. Synergistic effects between these factors and others significantly improved the explanatory capacity of individual factors for spatial variation in the drought. The correlation coefficients between TVDI and precipitation and between TVDI and NDVI were -0.695 and -0.51, respectively. Average annual TVDI was higher in the subsidence areas than in the non-subsidence areas. 【Conclusion】 From 2002 to 2018, TVDI spatiotemporally varied in the region, and drought severity was higher and more prevalent in the southwest than in the northeast. Precipitation, NDVI and soil type are the factors that affected drought most. These factors combine to explain the spatiotemporal variation in TVDI more than by any signal factor. Furthermore, the interplay among precipitation, NDVI, soil type and other geographical factors impacts the spatial variation in TVDI. It is important to highlight that collapses in coal mining could have contributed to drought occurrence.

Objective To compare the expression levels of pncA gene in pyrazinamide （PZA）-resistant and multidrug-resistant Mycobacterium tuberculosis before and after PZA drug stimulation， and to explore the relationship between PZA-resistant Mycobacterium tuberculosis and pncA gene expression. Methods PZA-resistant and multidrug-resistant Mycobacterium tuberculosis was cultured， and the minimal inhibitory concentration （MIC） of rifampicin and PZA was detected. The strains were cultured in medium containing 0 and 50 μg/mL PZA， and the expression level of pncA was detected by real-time fluorescence quantitative PCR. Results The MIC of PZA of 21 strains of Mycobacterium tuberculosis was ≥ 1 600 μg/mL，400-800 μg/mL for 12 strains， and 100-200 μg/mL in 5 strains，and their corresponding PZA resistance levels were defined as high，medium and low，respectively. The median MIC of rifampicin was 128， 128 and 64μg/mL， respectively. Chi-square test showed that there was no significant difference between any two groups （all P > 0.05）. According to the relative quantitative 2-ΔΔCt method， the expression levels of pncA in the high，medium and low levels of PZA drug-resistant Mycobacterium tuberculosis was 0.904（0.202， 2.653）， 1.157（0.658， 1.511） and 1.147（0.372， 1.347）， and 1.544（0.611， 3.191）， 0.846（0.421， 1.237） and 0.726 （0.225， 3.017） in the 50 μg/mL treatment group，respectively. There was no significant difference in pncA gene expression between the control and PZA drug-containing culture groups（P > 0.05）. Conclusion No significant changes are observed in the expression levels of pncA in multidrug-resistant and PZA-resistant Mycobacterium tuberculosis before and after PZA drug stimulation.

Scanning electron microscopy, transmission electron microscopy and energy disperse spectrum were used to analyze the morphologies, microstructures and compositions of Hf-rich inclusions in DZ125 and DZ22 Ni-based superalloys. The solidification microstructures of Ni-based alloys with different Hf additions were investigated by simulation experiments, and the formation mechanism of Hf inclusions was clarified. The results indicate that there are irregular inclusions on the edges of DZ125 and DZ22 alloys. The white inclusions are HfO2 phase, and the accompanying gray inclusions mainly comprise Al2O3. The Hf has a strong tendency to accumulate in the alloy, and large size Hf-rich phase of above 100 μm can form in the alloy when the Hf content is high. With the decrease of Hf content, the Hf-rich phases become smaller and distributed more evenly. At high temperature, Hf has a high strong driving force of spontaneous reaction with oxygen in the alloy melt and ceramic shell/core oxides, leading to the formation of HfO2 inclusions on the casting surface. When the dispersion of Hf is insufficient, Hf tends to segregate at the interface of oxide ceramic phases and melt, reacting with Al2O3 in the ceramic and SiO2 in the silica sol binder at high temperature, resulting in the formation of HfO2 inclusions on the casting surface.

ObjectiveThe root system is an important component of plant composition, and its growth and development are crucial for plants. Root image segmentation is an important method for obtaining root phenotype information and analyzing root growth patterns. Research on root image segmentation still faces difficulties, because of the noise and image quality limitations, the intricate and diverse soil environment, and the ineffectiveness of conventional techniques. This paper proposed a multi-scale feature extraction root segmentation algorithm that combined data augmentation and transfer learning to enhance the generalization and universality of the root image segmentation models in order to increase the speed, accuracy, and resilience of root image segmentation.MethodsFirstly, the experimental datasets were divided into a single dataset and a mixed dataset. The single dataset acquisition was obtained from the experimental station of Hebei Agricultural University in Baoding city. Additionally, a self-made RhizoPot device was used to collect images with a resolution pixels of 10,200×14,039, resulting in a total of 600 images. In this experiment, 100 sheets were randomly selected to be manually labeled using Adobe Photoshop CC2020 and segmented into resolution pixels of 768×768, and divided into training, validation, and test sets according to 7:2:1. To increase the number of experimental samples, an open source multi-crop mixed dataset was obtained in the network as a supplement, and it was reclassified into training, validation, and testing sets. The model was trained using the data augmentation strategy, which involved performing data augmentation operations at a set probability of 0.3 during the image reading phase, and each method did not affect the other. When the probability was less than 0.3, changes would be made to the image. Specific data augmentation methods included changing image attributes, randomly cropping, rotating, and flipping those images. The UNet structure was improved by designing eight different multi-scale image feature extraction modules. The module structure mainly included two aspects: Image convolution and feature fusion. The convolution improvement included convolutional block attention module (CBAM), depthwise separable convolution (DP Conv), and convolution (Conv). In terms of feature fusion methods, improvements could be divided into concatenation and addition. Subsequently, ablation tests were conducted based on a single dataset, data augmentation, and random loading of model weights, and the optimal multi-scale feature extraction module was selected and compared with the original UNet. Similarly, a single dataset, data augmentation, and random loading of model weights were used to compare and validate the advantages of the improved model with the PSPNet, SegNet, and DeeplabV3Plus algorithms. The improved model used pre-trained weights from a single dataset to load and train the model based on mixed datasets and data augmentation, further improving the model's generalization ability and root segmentation ability.Results and DiscussionsThe results of the ablation tests indicated that Conv_ 2+Add was the best improved algorithm. Compared to the original UNet, the mIoU, mRecall, and root F1 values of the model increased by 0.37%, 0.99%, and 0.56%, respectively. And, comparative experiments indicate Unet+Conv_2+Add model was superior to the PSPNet, SegNet, and DeeplabV3Plus models, with the best evaluation results. And the values of mIoU, mRecall, and the harmonic average of root F1 were 81.62%, 86.90%, and 77.97%, respectively. The actual segmented images obtained by the improved model were more finely processed at the root boundary compared to other models. However, for roots with deep color and low contrast with soil particles, the improved model could only achieve root recognition and the recognition was sparse, sacrificing a certain amount of information extraction ability. This study used the root phenotype evaluation software Rhizovision to analyze the root images of the Unet+Conv_2+Add improved model, PSPNet, SegNet, and DeeplabV3Plu, respectively, to obtain the values of the four root phenotypes (total root length, average diameter, surface area, and capacity), and the results showed that the average diameter and surface area indicator values of the improved model, Unet+Conv_2+Add had the smallest differences from the manually labeled indicator values and the SegNet indicator values for the two indicators. Total root length and volume were the closest to those of the manual labeling. The results of transfer learning experiments proved that compared with ordinary training, the transfer training of the improved model UNet+Conv_2+Add increased the IoU value of the root system by 1.25%. The Recall value of the root system was increased by 1.79%, and the harmonic average value of F1 was increased by 0.92%. Moreover, the overall convergence speed of the model was fast. Compared with regular training, the transfer training of the original UNet improved the root IoU by 0.29%, the root Recall by 0.83%, and the root F1 value by 0.21%, which indirectly confirmed the effectiveness of transfer learning.ConclusionsThe multi-scale feature extraction strategy proposed in this study can accurately and efficiently segment roots, and further improve the model's generalization ability using transfer learning methods, providing an important research foundation for crop root phenotype research.

Deoxynivalenol (DON) contamination in cereals and cereal products has the potential to pose a threat to human health. The biodetoxification technique, which uses biological enzymes to transform mycotoxins into less toxic product, is an environmentally friendly and highly effective approach to detoxifying mycotoxins. In this study, a gene designated adh2, encoding DON detoxifying enzyme, was identified by homology search from the genome sequence of DON-detoxifying strain Devosia sp. FJ2-5-3. Subsequently. The adh2 gene was cloned and expressed. Then, the enzymatic properties of its encoding enzyme was further characterized. The results showed that the length of the adh2 gene in Devosia sp. FJ2-5-3 was 1770 bp and the encoded ADH2 enzyme consisted of 589 amino acids, with a signal peptide of 24 amino acids length present at the N-terminus and belonging to type I of the PQQ-dependent alcohol dehydrogenase family (Type I PQQ-ADH). The enzyme exhibited the optimal activity at pH 9 and a temperature of 35 °C, and it retained over 50% of enzyme activity after incubation at 65 ℃ for 4 hours, indicating its good thermal stability. In addition, Ca2+ was found to be an essential cofactor for ADH2, while both 1% of ethanol and isopropanol showed significant inhibitory effects on its activity. The Km and Kcat values of ADH2 for DON were 708.00±47.01 μg/mL and 3.37±0.11 S–1, respectively. These results could provide reference information for the subsequent industrial application of DON detoxification enzymes.

【Objective】 Drought is a stress that crops often experience during their growing season, and comprehending its spatiotemporal dynamics in a region is important to improve agricultural management. In this paper, we propose to predict drought using temperature vegetation dryness index (TDVI). 【Method】 The studied site was a mining area in Shendong, Shandong province. We acquired 36 Landsat images during the growing seasons from 1991 to 2018. The TVDI calculated from these images was used to estimate the spatiotemporal dynamic of drought for different vegetations using mathematical statistical analysis methods, including deviation analysis, linear tendency analysis and spatial transfer matrix. 【Result】 ①Intra-annually, the value of TVDI was low from June to September; overall, the UF~UB curve was less than 0, and the TVDI exhibited a decreasing trend. Inter-annually, the value of TVDI was greater than 0 in 1991, 2002, 2007 and 2010, and showed an increasing trend from 1991 to 2010. The deviation value of TVDI was less than 0 in 2014 and 2018 and showed a decreasing trend from 2010 to 2018. ②Spatially, the value of TVDI was high in the southwest and low in the northeast, and the areas that experienced drought had declined from 1991—2010. ③Trend analysis showed that the areas where the TVDI had decreased from 1991—2010 was larger than the areas where the TVDI had increased. The areas where the TVDI had decreased were 2 394.74 km2 at the most, while the areas where the TVDI had increased were 425.91 km2 at the least. ④Majority of the studied region has undergone a transition from relatively dry state to normal or wet state, and the transition in the opposite direction is less extensive. 【Conclusion】 Using TVDI calculated from satellite images to monitor spatiotemporal dynamics of drought in the mining area in Shendong is accurate and robust. Our findings have important implication for help land reclamation in mining areas.

【Objective】 Chemical quality of surface water bodies is affected by many factors but most of them are driven by oxygen. Bioavailable oxygen in water decreases after the water surface is frozen, and this paper investigates how this impacts water quality in Ulansuhai lake in Inner Mongolia. 【Method】 Ice and water samples were taken in January 2021 from 10 sites in the lake. Contents of CODMn, nitrate, total phosphorus (TP), total nitrogen (TN), fluoride and copper in each sample were analyzed. They were compared to those measured before the lake was frozen. Change in these chemicals due to freezing was assessed using the single-factor and the comprehensive water quality identification index, as well as the principal component analysis. 【Result】 ① Single factor water quality identification index analysis indicated that the content of all chemicals in fluid water was ranked in the order of water underneath ice≥water before freezing≥melted ice. The pollution degree of the six chemicals was ranked in the order of TN>TP>CODMn>NH3-N>copper>fluoride. The chemicals that resulted in water quality classification change were CODMn, NH3-N and TN. ② Comprehensive water quality identification index analysis showed that freezing worsened the water quality in all 10 sampling sites, though the deterioration varied with sampling sites. Nitrate, TN and TP had the greatest influence on water quality, as increasing nitrogen and phosphorus risked eutrophication. Spatially, water quality in the lake area was ranked in the order of outlet area>middle lake area>inlet area. 【Conclusion】 Surface freezing in Ulansuhai Lake increased chemical concentrations in the water beneath the ice, leading to water quality deterioration. To ameliorate water pollution, discharge of pollutants to the lake, especially for TN and TP in autumn and winter, should be reduced.

【Objective】 Over-extraction of groundwater over the past decades has resulted in shallow groundwater table dropping at an alarming rate in most regions in Hebei province. Reducing groundwater extraction for wheat winter irrigation has been proposed as a remedy to reverse this trend. Quantitative understanding of wheat yield reduction due to the restricted groundwater extraction and its consequence for groundwater dynamics is essential. Taking a piedmont plain of Taihang Mountain as an example, this paper investigates how to minimize the wheat yield loss by optimizing irrigation frequency when the irrigation amount is the same. 【Method】 The study was based on numerical simulation. We designed three scenarios with the irrigation amount kept the same at 90 mm, but the crop was irrigated at different frequencies. For each frequency, we simulated the winter wheat yield, variation in shallow groundwater table and soil water balance in the 0~200 cm of soil using the modified SWAT model. We divided the simulation area into 22 sub-basins, and the optimal irrigation frequency for each subbasin was calculated based on the index of crop-groundwater irrigation productivity. 【Result】 ① Irrigating the crop twice, one at jointing and one at the heading stages, at equal irrigation amount (45 mm) gave the highest winter wheat yield, with the average yield reduced approximately by 20% compared to business-as-usual irrigation method. ② Irrigating all 90mm of water at the jointing stage led to largest irrigation water leaching. ③ Increasing the irrigation frequency from two to three with the same irrigation amount in each (30 mm) did not noticeably change water leaching and evapotranspiration, but increased soil evaporation at the expense of transpiration. ④ To minimize yield reduction, 13 subbasins (approximately 54% of the studied area) should irrigate once only, 8 subbasins (approximately 40% of the studied area) should irrigate twice each with 45 mm of water, and one subbasin (approximately 6% of the studied area) should irrigate three times each with 30 mm of water. 【Conclusion】 Reducing groundwater extraction for winter wheat irrigation to 90 mm could mitigate shallow groundwater table falling by 60%~75% at the price of yield reduction of 20%~25%. To minimize the yield reduction, different regions should adjust the irrigation frequencies based on its heterogeneous aquifers. Optimizing irrigation frequency should consider the trade-off effect of irrigation on groundwater conservation and crop production, as well as irrigation water use efficiency.

As a new type of energy storage device, aqueous zinc-ion capacitors (AZICs) have excellent performance, such as high power density, high energy density, long cycle life and high safety.AZICs have a high application prospect in the field of civil electronic equipment and military electrified weapons and equipment, and are expected to become a new generation of energy storage scheme instead of lithium-ion batteries.In this paper, the recent advances of carbon-based materials for zinc ion capacitors, such as activated carbon, carbon nanotubes, graphene and biomass derived carbon were summarized. The zinc ion storage performance of MXenes was analyzed in detail, and the energy storage mechanisms of transition metal oxides were revealed. It is pointed out that developing the cathode materials with high capacity, high voltage tolerance and low temperature adaptability is of great importance.

Background Alcoholism can lead to alcoholic myopathy. Although there are over ten biomarkers used to evaluate this disease, their diagnostic value remains controversial. Objective To systematically evaluate the effects of alcoholic myopathy on levels of relevant inflammatory factors and oxidative stress markers. Methods The VIP Database for Chinese Technical Periodicals, Wanfang Data Knowledge Service Platform, China National Knowledge Infrastructure, Web of Science, PubMed, Embase and Cochrane Library databases were searched for animal intervention studies on inflammatory factors and oxidative stress markers in alcoholic myopathy from February 1, 1990 to August 31, 2021 to retrieve. RevMan 5.4.1 was used for Meta-analysis. Outcome measures included reduced glutathione (GSH) and malondialdehyde (MDA) levels as well as the mRNA expression levels of insulin-like growth factor 1 (IGF-1) and interleukin 6 (IL-6) . Results Ultimately, 17 animal interventionstudies were included, and the results of Meta-analysis showed that the levels of IGF-1 mRNA expression〔SMD=-3.09, 95%CI (-5.75, -0.43) , P=0.02〕and GSH levels〔SMD=-4.20, 95%CI (-6.24, -2.17) , P

The paper reviews the current focus and future direction of China's research in the field of territorial space use zoning and aims to provide a scientific basis for China's spatial planning and territorial and spatial land management with the wider goal of improving the system of ecological civilization to promote the modernization of national governance systems and governance capacities. We use CiteSpace, a visualization software and method of bibliometric analysis, to create a knowledge map and systematically categorize the research trends and development context of territorial space use zoning research, based on 662 relevant papers published from 1979 to 2020 and cited on HowNet. Research on territorial space use zoning in China continues to emerge, and the number of published papers is increasing. The research was divided into three stages: the land use zoning stage (1992-2006), the natural ecological space use zoning stage (2007-2017), and the territorial space use zoning stage (2018-present). The main research keywords in the three periods show that scholars have consistently maintained an enthusiasm for the study of "land use". The keyword "land use" had a high centrality of 0.28. Close cooperation among authors formed a large-scale scientific research cluster. Colleges and universities published the most, followed by scientific research institutions and public institutions; the main outputs of public institutions such as China Land Surveying and Planning Institute are policy documents, the influence of which should not be underestimated. 2) The research on territorial space use zoning was national policy-oriented under the profound influence of the changing background of the times. Zoning theory developed from the theory of geographical differentiation and advantageous location into the concept of main functional zone regulation, and then to the present concept of sustainable development. Zoning systems were constantly optimized, and research focuses were diverse. Some provinces and cities conducted practical explorations based on local conditions because of "Three zones and three lines". "Three zones and three lines" refers to the areas corresponding to the three types of urban space, agricultural space, and ecological space, and the three control lines corresponding to the urban development boundary, the permanent basic farmland protection red line, and the ecological protection red line. In the face of the complexity and dynamics of territorial space, research methods have changed from qualitative or quantitative methods to focus on the application of modern science and technology. Most of the research on zoning control focuses on three aspects: discovery of existing problems, enlightenment from foreign experience, and research on zoning practice. Considering the existing problems, such as conventional research contents, shallow scientific validation studies, insufficient theoretical improvements, few applications of multidisciplinary integration and big data, future researches should focus on four directions as follows: carrying out the theoretical research related to territorial space use zoning; deepening use zoning research on ecological space, marine space and rural construction space; broadening the research perspective of territorial space use zoning based on the construction needs of territorial space use control system; implementing innovative methods and technologies for application based on multidisciplinary integration.

BackgroundThe passive residual heat removal (PRHR) system is an important innovative design of the advanced pressurized water reactor technology. Under accident conditions, PRHR system can transport decay heat in the form of natural circulation to ensure core cooling. However, the heat exchange function of PRHR system will be lost when the PRHR pipeline breaks. With development of the accident process, the coupling effect between different safety equipments of the passive core cooling system (PXS) will be affected. Besides, thermal hydraulic state of the reactor coolant system (RCS) will also be affected via complex interaction mechanism. As a result, the new thermal hydraulic phenomena occur, and thus ultimately affecting the accident mitigation capacity of the PXS.PurposeThis study aims to confirm the safety characteristics of PXS and identify the new thermal hydraulic phenomena of advanced passive nuclear power plant during accident with multiple failures.MethodsA series of integral effect tests of loss of coolant accident (LOCA) were conducted on the advanced core-cooling mechanism experiment (ACME) facility. The influence of failure of PRHR HX flow and heat exchanging function on LOCA accident process were investigated on the basis of the test cases including PRHR pipeline break and cold leg (CL) break. The unique thermal hydraulic phenomena occurred during PRHR LOCA were explored, and their influence laws on the coupling effect among PXS safety equipments, and the influence laws on thermal hydraulic state of RCS were obtained.ResultsThe results show that there is a momentary reverse flow and heat transfer process in PRHR HX at the beginning of PRHR LOCA compared with typical CL LOCA. Besides, the natural circulation process between the core and steam generators (SGs) plays a critical role in cooling and depressurization of RCS, and its corresponding time-averaged heat transfer power is increased by about 30%. Besides, the asymmetric arrangement of PXS leads to a significant difference of transient thermal hydraulic state between the RCS branches, namely the PRHR cools the coolant via one RCS loop while two core makeup tanks (CMTs) inject the cold water to the core via the other RCS loop, and the pipeline resistance distribution shows a significant impact on the injection performance of safety equipment with low driven head such as CMTs.ConclusionsThe unique and important thermal hydraulic phenomena in the early stage of the accident, namely reverse flow and heat transfer process in PRHR HX and natural circulation process between core and SGs, are identified. The asymmetric arrangement effect will be more noticeable when the break occurs in PRHR pipeline.

【Background】 Along with drought, soil salinization is one of the most important abiotic stresses facing agricultural production in arid and semi-arid regions like Xinjiang in northwest China. Saline soil is estimated to have reached 11 million hm2 in Xinjiang, and is a major limiting factor in cotton industry in this region. Accurately measuring soil salinity is hence important to safeguard cotton production in Xinjiang. 【Objective】 The purpose of this paper is to present a new method to estimate salinity distribution at field and regional scales to help improve irrigation and cultivation management. 【Method】 The experiments were conducted at Alar reclamation area in southern Xinjiang. Electrical conductivity of 540 soil samples taken from 30 cotton fields with different salinization levels were measured in soil profile at 0~0.375, 0~0.750, and 0~1.000 m depth. Using the electromagnetic induction data, linear and nonlinear models were constructed to inversely calculate the electrical conductivity of soil at field and regional scales respectively. Stability and reliability of the models was verified against ground-true data using the sample-size-reduction method. 【Result】 At field scale, the coefficient of determination R2 associated with the multiple linear regression model (MLR), the partial least square regression (PLSR) model and the principal component regression model (PCR) varied from 0.88 to 0.95, while their associated R2 for regional scale was from 0.34 to 0.53. The R2 of the nonlinear model built on the random forest (RF), neural network (NN) and support vector machine (SVM) varied between 0.60 and 0.85, with the RF most accurate. The R2 of the RF model for calculating the electrical conductivity of the soil profile at 0~0.375, 0~0.750, 0~1.000 m was 0.80, 0.85 and 0.84, respectively. Compared with the linear model, the model for regional scale significantly improved the accuracy. The sample size in the RF model for regional scale was reduced from 540 to 240, while the accuracy remained almost unchanged, indicating the regional-scale model can reduce the number of soil profile without compromising modelling accuracy. 【Conclusion】 For constructing the inversion model for estimating soil-profile electrical conductivity at regional scale, the random forest method is most accurate.

In order to develop a binderless phase cemented carbide to reduce the application of cobalt in conventional cemented carbides,(W,Mo)C/Al2O3/La2O3 were prepared by chemical methods. Ammonium paratungstate,ammonium molybdate,aluminum nitrate,lanthanum nitrate,urea and glucose were used as raw materials to explore the different ratios of nitrate,urea and glucose by low temperature combustion method, and the optimal ratio of carbon was obtained to prepare (W,Mo)C/Al2O3/La2O3powder.The (W,Mo)C/Al2O3/La2O3 binderless phase materials were prepared by SPS sintering at 1500-1800 ℃.The mechanical properties were studied and the strengthening and toughening mechanism was analyzed. The results show that the optimum molar ratio of nitrate to urea is 1:2,the optimum molar ratio of nitrate to glucose is 1:0.5,the grain size is reduced by 0.28 μm after adding glucose,and the specific surface area is increased by 75.64%.Density,Vickers hardness and flexural strength reach maximum at 1600 ℃:98.45%,2202HV30 and 1203 MPa,respectively,and the fracture toughness reaches a peak of 7.52 MPa·m1/2 at 1500 ℃. (W,Mo)C/Al2O3/La2O3 are mainly intergranular fracture and transgranular fracture due to the influence of grain refinement and toughening of the second phase particles at 1500-1600 ℃;the reason why (W,Mo)C/Al2O3/La2O3 is mainly intergranular fracture at 1700-1800 ℃ is grain growth and the appearance of pore.

Mn2O3/Fe2O3/few layer graphene/sulfur composites were prepared by melted salt method, interlayer catalytic exfoliation, annealing and melt diffusion method in sequence for lithium-sulfur batteries cathode. The three-dimensional conductive network formed by highly conductive few layers graphene provides electron transfer channel, thus promoting the high capacity performance of lithium-sulfur batteries. The metal oxides distributed uniformly on the surface of graphene exhibit strong interaction towards polysulfides, which can restrain the dissolution of polysulfides and shuttle effect and promote the cycling performance of lithium-sulfur batteries. As a result, the Mn2O3/Fe2O3/FLG30/S cathode shows high capacity and cycling performance. The cathode delivers an initial discharging capacity of 886.3 mAh·g-1 with a high capacity retention of 88.1% after 100 cycles at rate of 0.1 C.

The dynamic monitoring of the geological environment in urban areas, including the monitoring of the urban surface stability and detailed monitoring of man-made objects on the surface, is very important for ensuring effective and safe urban development. Spaceborne time-series InSAR technology is widely used to monitor urban deformation due to its large scale, high accuracy, and ability to acquire high-density spatial deformations. In recent years, with the operation of high-resolution satellite missions, time-series InSAR has also been widely used to monitor infrastructures. In this paper based on our long-term monitoring research experience in urban areas using the time-series InSAR technique, we review the application of some typical time-series-InSAR cases to the urban environment, including the monitoring of urban surface displacement and typical large infrastructures, including the airports, elevated road networks, bridges, railways, and subways. Based on various datasets including high-resolution TerraSAR-X images, Cosmo-SkyMed images, and recent Sentinel-1 images obtained at no cost, and the research problems and corresponding solutions identified in published monitoring research, we found good results to have been achieved using this application. With the implementation of more and more satellite missions, this technology will provide more possibilities for urban monitoring.

Objective To analyze the clinical effect of flexible fiber splint on traumatized permanent teeth with horizontal root fractures and to provide the basis for clinical treatment. Methods The case data of 54 permanent root anterior teeth with horizontal root fractures were collected. Patients with affected teeth were followed for 1 to 2 years to analyze the root fractures. The preservation rate and pulp survival rate were analyzed, and further analysis was performed on the effects of the root fracture location (cervical 1/3, Mid-root, apical 1/3), root development stage (mature permanent teeth, young permanent teeth), dislocation of the coronal fragment ( 1 mm) on root fracture healing and dental pulp survival. Results A total of 54 teeth with root fractures were treated according to the International Dental Trauma Association Treatment Guidelines. After the application of flexible fiber splint fixation, the tooth preservation rate was 90.7%, and the pulp survival rate was 75.9%, the hard tissues healing rate was 61.1%(33/54). There were no significant differences in the locations of root fractures, the developmental stages of the roots, or the degrees of dislocation of coronal fragment on the types of root fracture healing or dental pulp survival (P > 0.05). Conclusion The flexible fiber splint has a wide range of indications. Except for affected teeth with the root fracture located above the alveolar crest, other types of horizontal root fractures in anterior teeth can be treated with flexible fiber splint fixation and can achieve a good prognosis.

Lithium-ion batteries (LIBs) have been considered a promising candidate of new energy storage device. Numerous researchers around the world are committed to develop new materials for high-performance LIBs. MXenes are new type of two-dimensional nanomaterials, which are composed of transition metal, carbides or/and nitrides, with large specific surface area, good electrical conductivity, high lithium storage capacity, excellent cycling and rate performances, etc., making them as LIBs materials with bright application prospects. A variety of MXenes materials (such as Ti2CTx, Ti3C2Tx, V2CTx, Nb2CTx, etc.) have been reported to be useful as LIBs electrode materials. In addition, MXenes materials can be combined with other LIBs active materials to build good conductive network, accelerate electron transport and lithium ion diffusion, and inhibit materials pulverization caused by volume expansion of active materials during electrochemical processes. Besides, researches on MXenes materials in solid electrolytes, binders, and conductive agents for LIBs have also been reported. In this paper, the major breakthroughs in the application of MXenes materials for LIBs were reviewed. The preparation methods, structural properties and lithium storage mechanism of MXenes materials were introduced. Moreover, the specific application, existing problems of MXenes materials in LIBs have been concentrated on.This review points out that researches of MXenes materials should take advantages of their hydrophilicity and conductivity poperties,and focus on the development of composite electrode meterials,self-supporting electrodes materials etc.,which will bring breakthroughs to the key technologies of high-performance lithium-ion batteries.

BackgroundWith the continuous development of nuclear technology, radioactive material exploration requires higher and higher detection accuracy of aerial gamma energy spectrometer, meanwhile, the wavelet packet soft threshold noise reduction method has the advantages of good noise reduction effect and high signal-to-noise resolution.PurposeThis study aims to find the optimal wavelet packet soft threshold noise reduction scheme for the aerial gamma energy spectrum.MethodsFirst of all, the aerial gamma energy spectrum obtained by CeBr3 detector was taken for noise reduction study using various wavelet packet soft threshold noise reduction scheme schemes. Then three noise reduction schemes were selected on the base of the peak signal-to-noise ratio (SNR) and applied to the accuracy measurements. Based on the improvement effect of the three noise reduction schemes on the accuracy, the best noise reduction scheme was finally found.ResultsThe best noise reduction scheme is a wavelet packet soft threshold noise reduction method using db14 for 7-layer decomposition. This noise reduction scheme can improve the peak signal-to-noise ratio of the aviation gamma energy spectrum from 23.22 dB to 39.50 dB and improve the measurement accuracy of the aviation gamma energy spectrometer by 3.19%.ConclusionsThe wavelet packet soft threshold noise reduction method has good noise reduction effect, less distortion, and can also improve the accuracy of the measurement, which is suitable for application in the data processing of aviation gamma energy spectrum.

Polymer electrolyte coated sulfur@carbon fiber composite solid electrode was prepared by the two methods of microscopic and macroscopic coating with polymer electrolyte in the cathode sheet of lithium sulfur battery. The microscopic morphology of the electrode was characterized by scanning electron microscopy, and the corresponding performances of the battery with different cathode structures were also analyzed. Results show that the electrode structure of microscopic polymer solid electrolyte coated active material is favorable for ion transfer. Macroscopically constructing a polymer solid electrolyte film on the electrode surface can improve the cyclic stability of the electrode and inhibit the shuttle effect. The all-solid lithium-sulfur battery assembled with the membrane electrode structure has good cycle performance. After 270 cycles, the Coulomb efficiency still keeps over 98 %.

A novel high specific capacity hybrid cathode material was designed by increasing the specific capacity of cathode material to improve the discharge performance under large current. The carbon fluoride-sulfur hybrid material was prepared through grinding, dispersing and melt-diffusion treatment. Electrochemical tests and analysis showed that the new material could achieve synchronous improvement of capacity and high current discharge performance. At the same time, it has the capacity of secondary reversible cycle charge and discharge. The research results show that the energy density and power density of carbon fluoride-sulfur cathode have outstanding advantages, it can be significantly improved at different current densities. The energy density and power density are increased by 433% and 10.7% respectively than that of the pristine carbon fluoride cathode.

Two types of ultrathin-flaky δ-MnO2 electrode materials (denoted as δ-MnO2-A and δ-MnO2-B) were synthesized through the reduction of potassium permanganate with manganese acetate and ethanol separately.The crystalline structure,chemical component,microstructure and pore size distribution of these nano-materials were determined by XRD,XPS,SEM/TEM and BET analysis.The electrochemical test demonstrates two δ-MnO2 electrode materials own similar specific capacitance and rate capability.Comparing to δ-MnO2-A,however,electrode material δ-MnO2-B contains a higher potassium and manganese vacancy content,and the lamellar structure of δ-MnO2-B is more legible and stable,therefore it displays a much more superior cycling stability.In 0.5mol/L Na2SO4 electrolyte,the specific capacitance of δ-MnO2 reaches 227F·g-1(1mV·s-1) and the capacitance retention rate is achieved 87.6% after 5000 cycles at 100mV·s-1.

A new type globular MnO2 flowers anchored graphene composites was synthesized via redox reactions among potassium permanganate/ethanol/graphene. The crystalline structure, chemical component, and microstructure of the composites were determined by XRD, TG, SEM/TEM and BET analysis. The electrochemical test demonstrates the globular MnO2 material possesses excellent specific capacitance while poor rate capability and cycling stability. By means of anchoring these globular MnO2 flowers onto graphene, the specific capacitance of graphene is significantly improved. Meanwhile, rate capability and cycling stability of the globular MnO2 material can be promoted remarkably. In 0.5mol/L K2SO4 electrolyte, the specific capacitance of the composites reaches as high as 295F·g-1 at 2mV·s-1, and maintains at 102F·g-1 even at a high scan rate of 1000mV·s-1.An outstanding capacitance retention of 96.3% is achieved for the composites after 1000 cycles at 100mV·s-1. It demonstrates the globular MnO2 flowers anchored graphene composites is a very potential electrode material for supercapacitors.

[Purpose/significance] Suggestions for the further deepening and development of the future open access publication of library and information science journals in China. [Method/process] By the methods of literature research and network research, this article investigated the status of open access publication of 24 kinds of journals of Library and Information Science in CSSCI, analyzes its deficiencies and problems in operation model, OA publication policy statement, OA publication content, and the construction of additional functions of journals. [Result/conclusion] Suggestions are made on the future development of open access publishing in Chinese Library and Information Science journals: try to change the mode of running journals, strive for the right to speak in cooperation with foreign publishers, supply the OA publishing policy statement and standardize the OA publication content, make full use of new media and new technologies to expand OA journal service capabilities.

Graphene is an ideal material for energy storage application as its excellent mechanical and physical properties. 3D printed graphene materials will be widely applied in energy storage field for its precisely controllable structure and it is easy to realize large-scale preparation. In this paper, the progress of 3D printed graphene materials synthesis technology and its application in energy storage field were reviewed. The viscosity and printability of graphene ink are key factors for realizing graphene 3D printing. Scalable preparation of graphene ink with facile process, controllable concentration and additive free will be the research focus of graphene 3D printing technologies in the future. The integrated printing of graphene energy storage devices such as graphene supercapacitor, lithium-sulfur battery and lithium ion battery is the development direction in this area.

Due to their sensitivity to a wide diversity of volatile gases, electronic noses are ideal instruments for measuring and monitoring odors and they are being applied in agricultural production testing, biological medicine detection, environmental monitoring, and food testing. An electronic nose (E-nose) utilizes a sensor array to provide a fingerprint response to a given odor, using pattern recognition software to identify and discriminate between odors. Each sensor in the array behaves like a receptor by responding to different odors to varying degrees. The changes are then transduced into electrical signals, which are preprocessed and conditioned before identification by a pattern recognition system. In this paper, recent electronic-nose systems and algorithms are reviewed which developed over the past two decades that have potential applications for detecting Chinese liquors, including brand identification, flavor detection, and the prediction of the ages. In addition, the technical design scheme and the application were detailed for the polymer quartz piezoelectric sensor E-nose.

In the preparation process of novel polymer quartz piezoelectric sensors using AT-cut quartz substrates and polymer materials, the roughness and the chemical characteristics of the substrate surface have a great influence on the production of the sensors. It could result in thickness-varied or defective films of the sensors, which make the sensor's frequency signals unstable. In this paper, a mechanical model of the sensor is presented, which takes into account the conditions that the film is thickness-varied and defective. The ANSYS software was used to obtain the vibration characteristics of the mechanical model under complex conditions by modal analysis. Results show that the natural frequency values of the sensor change from a stable state to a divergence state with the increase of the film defect in the radius, and the natural frequency values of the sensor increase linearly with increase of the thickness for the film. It indicates that the thickness of the film should be kept uniform and the defect radius should be limited within 0.5 mm during producing the sensors. The results provide an important basis for producing the qualified polymer quartz piezoelectric sensors.

The formation conditions of shale gas in Wufeng-Longmaxi Formation of Yanjin-Gongxian area were analyzed on the basis of field observation and experimental data,and then the main factors for shale gas accumulation were discussed. Results show that black shale at the bottom of Wufeng-Longmaxi Formation is a deep-water shelf deposit product. The dessert shale gas from the first stage of Wufeng to the fourth stage of Longmaxi was complete. The organic carbon content is between 2.7%-6.0%. Mainly for the high organic carbon content,the thickness of black shale rich in organic matter is 30-50 m. In the high gas horizon,nanometer organic pores and pyrite intracrystalline pores are abundant,and the average rate of porosity is 2.28%-3.48%,providing a good reservoir space for the adsorbed gas and free gas. Structural strength in the research area is weak and large faults are less. There are good conditions of roof and floor. The pressure coefficient is more than 1,which reflects the suitable preservation condition. The main factors for shale gas accumulation are as follows:deep shelf sedimentary environment,high organic carbon content,abundant nanometer pores,high level porosity,and high pressure coefficient.

Graphene materials with excellent mechanical and physical properties as well as two-dimensional flexible morphology are ideal reinforcement nanofillers for aluminum matrix nanocomposites. Rapid progress in graphene materials and nanocomposites fabricating technology promotes the development of advanced graphene reinforced aluminum matrix nanocomposites for structural and functional applications. Nevertheless, the dispersion of graphene nanofillers within aluminum matrix and the interfacial controlling between them remain longstanding challenges in the fabrication of graphene reinforced aluminum matrix nanocomposites. This paper focused on the recent development of the fabrication and characterization of graphene reinforced aluminum matrix nanocomposites, including the dispersion and consolidation technology of graphene reinforced aluminum matrix nanocomposites as well as their structural characters and mechanical behaviors. The mechanical performances of aluminum matrix were remarkably enhanced by the introduction of graphene, which can increase further by optimizing process parameters, improving microstructure and controlling interface between aluminum and graphene. Furthermore, in order to realize the engineering application, more investigation should be given on the corrosion, thermal and electrical properties. It is also very important to develop a new method with low cost and large-scale production. As a novel 2-dimension structure and unique surface state of graphene, the reinforcing and toughening mechanism was discussed.

In view of the problem of poor stability, low efficiency existed in distance detection method of low power semiconductor laser pointer, a measurement method of detection distance of laser pointer based on CCD detection technology was put forward. The detection distance equation of laser pointer with human eye as the receiver was deduced and modeling by using the CCD sensor and image processing technology. The function mathematical model between the two parameters of optical power and gray scale was also established. The least square method was used to solve correlation coefficient of the equation，the detection distance can be solved by correlation coefficient. The method realizes quantitative detection of detection distance of low power semiconductor laser pointer. The feasibility of the method is verified by experiment.

Body improvement of lightweight mini-truck made vehicle mass reduction of 10. 9kg. After constraints and forces is carried out to calculate the bending stiffness and torsional stiffness around the vehicle in the pre-processing software of the finite element to model,in the contrast,it is found that the bending stiffness fell 1. 28 percent,and 2. 49 percent decline after the torsional stiffness,so they are down slightly. Tests of mini-truck is done on the real enhanced road,it is good performance.

Glacial lake area change is an indicator of global climate change. The topography of Tianshan Mountains is complex, and the glacial lakes are widely distributed, so their variation characteristics and response mechanism to climate change need to be further explored. Based on the Google Earth Engine (GEE) platform, this paper studied the changes of glacial lakes in the Tianshan Mountains in the past 20 years, and analyzed the driving forces in combination with precipitation and temperature. The results showed that: (1) There were 1532 glacial lakes in Tianshan Mountains in 2020, with an area of 164.02 km². The distribution of glacial lakes in the Tianshan Mountains was characterized by more in the west and less in the east, and glacial lake area with an annual average growth rate of 3.47% and 0.63% in the east and west, respectively. (2) The glacial lakes at lower altitudes (<3600 m) in the study area generally showed an expanding trend, and the glacial lakes with an area <0.1 km2 showed a more obvious change. (3) The results of the geographic detector showed that temperature and glaciers were the main driving factors affecting the change of the glacial lakes in Tianshan Mountains. From 2000 to 2020, the precipitation in the eastern Tianshan Mountains increased significantly, while the temperature showed an insignificant trend of decrease. The glacial lake area in this region continued to expand under the stable and sufficient glacial meltwater and runoff recharge. Research results can provide scientific basis for the rational development of water resources and the risk assessment of glacial lake outburst disaster in the Tianshan Mountains. [ABSTRACT FROM AUTHOR]

To examine the regulatory mechanisms of oligopeptides derived from soft-shelled turtle protein on tubulin activity in tumor cells, this study employed three specific oligopeptides D-7-A, E-7-W, and G-8-V obtained from soft-shelled turtle protein. The objective was to assess their impact on tubulin polymerization and depolymerization, investigate their interaction with tubulin, and elucidate the mechanisms induce apoptosis in tumor cells. The results showed that the three oligopeptides exhibited similarities to vincristine and acted as inhibitors of tubulin polymerization, their respective IC50 values was 3.72, 5.01, and 5.95 µmol/L. Furthermore, the molecular docking analysis revealed that D-7-A interacted with the active center of α-tubulin 4X1I, specifically binding to Ser178 and Thr179. The active center of E-7-W was found to be bound by Gln15, Thr225, Tyr224, Tyr210 and Arg214. Similarly, G-8-V was observed to bind to Gln11, Ser178 and Asp329 at the active center, exerting a significant impact on α-tubulin. The results of cell experiments showed that D-7-A, E-7-W and G-8-V had dose-dependent inhibitory effects on A549 cells, with IC50 values of 2003±72, 1877±102 and 1789±137 μmol/L, respectively. The G-8-V exhibited the most potent inhibitory effect on A549 cells, leading to the induction of apoptosis. Moreover, the apoptosis rate demonstrated a significant increase with prolonged drug treatment time. The underlying mechanism of action involved the inhibition of tubulin polymerization and the induction of apoptosis by perturbing the valence bond of α-tubulin. [ABSTRACT FROM AUTHOR]

Aiming at the flicker problem faced by vehicle streaming media rearview mirror under LED signal light environment, meanwhile, considering the impact of rapid local image motion and complex edge textures on image restoration, a real-time flicker mitigation system based on FPGA(Field Programmable Gate Array) is proposed in this paper. Firstly, the constraint conditions of the flicker pixels are established according to the features of flicker images such that the flicker region are efficiently detected through three consecutive frames. Then, a motion estimation algorithm based on neighborhood images groups is proposed, the image matching criterion is improved, and the neighborhood images vectors is clustered to enhance image inpainting effect in complex scene. Finally, a parallel pipeline processing architecture for video data streams is designed based on the ZYNQ(ZYNQ-7000 All Programmable SoC) platform to achieve system acceleration. The experimental results show that the proposed system can satisfy the real-time processing requirement of 800x480 resolution and 30 fps video, and has good mitigation effect on flickering images in complex scenes. [ABSTRACT FROM AUTHOR]

Objective To dynamically observe the changes in hypoxia-inducible factor 1α (HIF-1α) and Bcl-2/adenovirus E1B19kDa-interacting protein 3 (BNIP3) in children with traumatic brain injury (TBI) and evaluate their clinical value in predicting the severity and prognosis of pediatric TBI. Methods A prospective study included 47 children with moderate to severe TBI from January 2021 to July 2023, categorized into moderate (scores 9-12) and severe (scores 3-8) subgroups based on the Glasgow Coma Scale. A control group consisted of 30 children diagnosed and treated for inguinal hernia during the same period, with no underlying diseases. The levels of HIF-1α, BNIP3, autophagy- related protein Beclin-1, and S100B were compared among groups. The predictive value of HIF-1α, BNIP3, Beclin-1, and S100B for the severity and prognosis of TBI was assessed using receiver operating characteristic (ROC) curves. Results Serum levels of HIF-1α, BNIP3, Beclin-1, and S100B in the TBI group were higher than those in the control group (P<0.05). Among the TBI patients, the severe subgroup had higher levels of HIF-1α, BNIP3, Beclin-1, and S100B than the moderate subgroup (P<0.05). Correlation analysis showed that the serum levels of HIF-1α, BNIP3, Beclin-1, and S100B wcrc negatively correlated with the Glasgow Coma Scalc scorcs (P<0.05). After 7 days of treatment, scrum levels of HIF-1α, BNIP3, Beclin-1, and S100B in both non-surgical and surgical TBI patients decreased compared to before treatment (P<0.05). ROC curve analysis indicated that the areas under the curve for predicting severe TBI based on scrum levels of HIF-1α, BNIP3, Beclin-1, and S100B wcrc 0.782, 0.835, 0.872, and 0.880, respectively (P<0.05), and for predicting poor prognosis of TBI wcrc 0.749, 0.775, 0.814, and 0.751, respectively (P<0.05). Conclusions Scrum levels of HIF-1α, BNIP3, and Beclin-1 arc significantly elevated in children with TBI, and their measurement can aid in the clinical assessment of the severity and prognosis of pediatric TBI. [ABSTRACT FROM AUTHOR]

We conducted a field experiment in the dry farming area in south Ningxia from 2018 to 2021, to explore the influence of tillage methods combined with mulching on soil bulk density, aggregate content, soil water storage and potato yield under different precipitation years. There were four tillage methods (15 cm depth ploughing, and 30 cm, 40 cm and 50 cm depth subsoiling) and three mulching measures (mulching with oat straw, plastic film and no mulching), with the ploughing depth of 15 cm without mulching as control. The results showed the combination of tillage and mulching effectively reduced soil bulk density in 0-60 cm layer after three years of farming compared with that prior to the experiment. Under the same tillage mode, the best effect was achieved in mulching with oat straw under different precipitation years. To be specific, the best effect in 20 cm and 40 cm soil layers was achieved in mulching with oat straw for 30 cm depth subsoiling, in 60 cm soil layer for 15 cm ploughing in wet year, and for 40 cm depth subsoiling in 20 cm, 40 cm and 60 cm soil layers in normal and dry years. In 0-20 cm soil layer, the content of >0.25 mm soil aggregate was the highest for 40 cm depth subsoiling with oat straw mulching in all the three years. In 20-40 cm soil layer, the content was the highest for 15 cm depth ploughing with oat straw mulching in wet year, and for 40 cm depth subsoiling with oat straw mulching in normal and dry years. In 40-60 cm soil layer, content was the highest for 15 cm depth ploughing with plastic film mulching, 30 cm depth subsoiling with plastic film mulching, and 30 cm depth subsoiling with oat straw mulching in wet, normal and dry years, which was increased by 18.8%, 27.0%, and 35.8%, respectively, compared with the control. In the key growth stage (from squaring to tuber expansion) of potatoes, soil water storage in 0-100 cm layer was optimal for 30 cm depth subsoiling with oat straw mulching in wet year and for 40 cm depth subsoiling with oat straw mulching in normal and dry years, with an increase of 19.4%, 19.5%, and 23.7%, respectively. Potato yield was the highest for 30 cm depth subsoiling with oat straw mulching in wet year and for 40 cm depth subsoiling in normal and dry years, with an increase of 84.6%, 81.7%, and 106.3%, respectively. The correlation analysis showed that improved soil physical properties played a significant role in increasing potato yield, with the most significant role of soil bulk density and soil water storage at the squaring stage. Potato yield was high at a tillage depth of 34.67-36.03 cm. We concluded that the combination of tillage method and mulching could effectively improve soil physical properties and increase soil water storage in the growth stage of potatoes, thereby significantly increa-sing potato yield. Potato yield in dry farming area could be enhanced through 30 cm depth subsoiling with oat straw mulching in wet years, and 40 cm depth subsoiling with oat straw mulching in normal and dry years. [ABSTRACT FROM AUTHOR]

To study the evolution of wheat traits and genetic diversity in southern Huang-Huai winter wheat region, the wheat varieties in the recent 20 years in southern Huang-Huai winter wheat region were as materials. The evolution of wheat traits and genetic diversity were explored from a new perspective by using Shannon-Wiener diversity index (H') and coefficient of variation analysis, fitting trend line after dimensionless traits, principal component analysis, comprehensive score (D' value) evaluation, regression model construction and other methods. The indexes used for the evaluation of wheat varieties in southern Huang-Huai winter wheat region and the germplasm with excellent performance were screened. The results showed that a total of 443 wheat varieties were bred in southern Huang-Huai winter wheat region from 2003 to 2022, and it could be divided into 3 stages based on the number of bred varieties: basic stable stage (from 2003 to 2017), temporary high stage after obvious uplift (from 2018 to 2019, and blowout eruption stage (from 2020 to present ). In recent 20 years, plant height of wheat in southern Huang-Huai winter wheat region decreased slowly with time-going; water absorption remained unchanged; spike number, grain number per spike, 1 000-grain weight, yield, basic seedlings, test weight, protein content, wet gluten content and stability time showed upward trend, among which 1 000-grain weight, yield, basic seedlings, test weight and wet gluten content had relatively strong upward trend. The increase of yield was mainly due to the increase of 1 000-grain weight. The proportion of high-quality special wheat (strong gluten wheat, medium strong gluten wheat, weak gluten wheat) increased in recent years, mainly due to the increase in the proportion of medium strong gluten wheat. The proportion of strong gluten wheat has not increased significantly, which was mainly limited by water absorption and stability time. The dispersion degree and evolution trend of agronomic traits and quality traits were quite different, but their genetic diversity was constantly improving with the year, and genetic stability should be further strengthened. The results of regression model construction showed that 5 traits could be used as the evaluation indexes of the comprehensive performance of wheat in southern Huanghuai winter wheat region, including spike number, yield, test weight, protein content and water absorption. Among 443 varieties, 'Jimai 336' 'Anke 1801' 'Jimai 44' Gushenmai 19' and 'Huawei 305, which had higher D', performed well and could be used as excellent germplasm resources in the breeding of strong gluten wheat. In the future, the breeders should strengthen breeding new varieties with high-quality special wheat, especially weak gluten wheat, and enhance the protection and utilization of germplasm resources. [ABSTRACT FROM AUTHOR]

Agriculture is an important part of the global ecosystem carbon cycle, which is greatly affected by drought. Therefore, understanding the impact of drought on the carbon sink intensity of agro-ecosystems helps to figure out the change regular of agro-ecosystem carbon cycle and provide a theoretical basis for realizing the control of carbon emissions. In this paper, the net ecosystem exchange (NEE) of winter wheat-summer maize rotation system in North China Plains is simulated by vegetation photosynthesis and respiration model (VPRM), and Drought Severity Index (DSI) is calculated based on evapotranspiration and normalized vegetation index to evaluate the agricultural drought intensity. The spatiotemporal response of NEE to agricultural drought is also assessed by using geographic detectors and de-trended analysis. The results show that the agricultural drought intensity in the northern part of North China Plains is more than that in the southern part of North China Plains during the growth period of winter wheat, and the agricultural drought intensity gradually decreases with the development of winter wheat. During the growth period of summer maize, North China Plains enters the rainy season and is generally wet. The carbon sequestration capacity of cropland ecosystem decreases with the increase in agricultural drought intensity, and the sensitivity of NEE of cropland ecosystem to agricultural drought is greater in the middle growth stage of winter wheat/summer maize than in the early and late growth stages. The spatial variability of agricultural drought has the largest explanatory power for NEE of winter wheat in March (q=0.68l). The explanatory power for NEE of summer maize is the highest in August (q=0.792). With the increase in agricultural drought intensity, wheat and maize fields change from strong carbon sink to weak carbon sink if grain carbon content is not considered, and finally change to carbon source if grain carbon content is considered. [ABSTRACT FROM AUTHOR]

The development of efficient visible light-responsive photocatalysts is of great importance to the advancement of photocatalytic technology. Bi2MoO6 was prepared via the citric acid (CA)-assisted solvothermal method and characterized by XRD, SEM, UV-Vis DRS, BET, and PL. The photocatalytic performance of the synthesized material was evaluated by ciprofloxacin (CIP) degradation, Escherichia coli (E. coli) and Staphylococcus aureus (S. aures) inactivation under visible light. Bi2MoO6 prepared with 3 mmol amount of CA, namely BM-3, exhibits the optimal photocatalytic activity. The CIP degradation efficiency of BM-3 reaches 89. 5% within 100 min, which is 2.45 times higher than that of BM-0 prepared without CA. In addition, BM-3 could completely inactivate E. coli within 150 min or S. aures within 200 min, causing concave surfaces and cell aggregation due to the leakage of cellular contents. Multiple cycles of experimentation were conducted to validate the stability of BM-3. The wide visible light absorption range, large specific surface area, and efficient photogenerated carrier separation efficiency were key factors contributing to the superior photocatalytic performance of Bi2MoO6 synthesized by the CA-assisted solvothermal method. [ABSTRACT FROM AUTHOR]

In order to study the characteristics of the structure of wind shear, the low-level wind shear at Urumqi Airport on 2021-11-26 was analyzed by using the FC-III wind light detection and ranging(LiDAR) data, the reanalysis data of National Centers for Environmental Prediction, and conventional meteorological observation data. The evolution of wind shear was calculated. The results show that, the wind shear process occurred under the condition of a specific terrain wind. The small scale of cold air caused the significant changes in wind direction and speed, the bottom of the southeast jet and the northwest wind belt form a vertical shear area inclined upward which led to the cold-front type of low-level wind shear. The wind field around airports had been changed 1 h before the occurrence of wind shear. And the wind shear area was detected 10 min earlier than the report from aircraft which based on the plan position indicator model, the area where wind shear occurred was significant variations in the southeast wind speed, and also followed the movement of cold air to the west. During the movement of cold air, the southeast wind layer became thinner and retreated to the west. Near the glide path 07#. There was not only a sharp reduction of the frontal crosswind, but also a significant change in wind direction. The cold air was wedged from 25# to 07# during 08:30 ~ 10:25. The small-scale of cold air activity at low altitude was captured, and a backward of evolution process and structure was figured out, which showed that the pathway entering the airport from northeast, and issued the wind shear warning. The study is helpful to improve the meteorological service support capacity. [ABSTRACT FROM AUTHOR]

For the VSC-HVDC system transmitting new energy， poor parameter matching between the new energy controller and the VSC-HVDC controller can lead to sub-synchronous and super-synchronous oscillation. To address this， an open-loop strategy based on virtual synchronous generator （VSG） control has been adopted. This strategy eliminates the inner and outer loops and the phase lock of traditional closed-loop control methods， optimizing the impedance characteristics of the VSC-HVDC system and reducing the risk of sub-synchronous and super-synchronous oscillations of new energy. It is also compatible with both islanded and grid-connected operating modes. To address bipolar power imbalance and excessive short-circuit current after faults in open-loop control， bipolar power balancing and fault ride-through （FRT） strategies have been proposed. The effectiveness of the proposed VSG control and FRT strategies has been validated through RTDS simulations.

This article summarized the nursing management of a patient with severe acute pancreatitis and distributive shock. Based on the comprehensive nursing risk assessment, an individualized nursing plan was established including fasting management, gastrointestinal decompression, inhibiting pancreatic secretion, Traditional Chinese Medicine enema, Mangxiao external application and targeted interventions on fluid resuscitation and vasoactive agent administration. Integrative nursing interventions are effective to relieve the abdominal pain and improve the early recovery of the patient. (本文总结1例重度急性胰腺炎合并分布性休克患者的护理经验。通过对患者进行综合全面的护理评估, 制定个性化护理计划, 包括禁食、胃肠减压、抑制胰腺分泌、中药灌肠、芒硝外敷等, 并针对液体复苏、血管活性药物的使用等干预措施实施优质护理, 有效缓解患者腹痛, 促进患者早期康复。)

The varying carbon emission characteristics of distributed resources result in spatial-temporal differences in emission intensity at various nodes in the distribution networks. To effectively support low-carbon analysis and optimization in distribution networks as well as low-carbon accounting and trading at the user side， a model for electricity-carbon coupling in active distribution networks is built. Using load flow tracking， quantitative analysis and research on the carbon emission flow in active distribution networks is conducted， incorporating carbon emission costs into the economic costs of the distribution system. Aiming for the minimum total economic cost of the power system， simulation analysis is carried out using the IEEE 33-node test case， validating the feasibility and efficacy of the proposed method.

Autotrophic denitrification technology has the advantages of no additional carbon source, low sludge yield and low cost. It is one of the promising technologies for deep denitrification of low C/N wastewater under the dual-carbon background. The selection of inorganic electron donor is the key to its wide practical application. According to the principle of denitrification, sulfur autotrophic denitrification is easy to produce acid and sulfate, iron denitrification consumes acid and accumulates nitrite, whereas sulfur-iron coupling autotrophic denitrification can combine the characteristics of both to maintain stable reaction pH and reduce secondary pollution. In this paper, the principle and characteristics of autotrophic denitrification based on sulfur, iron and sulfur-iron as electron donors were analyzed, and the dominant bacteria under different electron donors were introduced. It was hoped to provide reference for improving nitrogen removal efficiency and reducing secondary pollution by sulfur based, iron based and sulfur-iron coupled autotrophic denitrification technologies.

In order to investigate the prevalent rules and characteristics of Aeromonas bacteria from river crabs in Jian¬gsu Province, the samples of river crabs were collected from the 20 counties (cities, districts) in Jiangsu Province, such as Sihong, Wuzhong and Xiangcheng, etc., for the isolation and cultivation of Aeromonas. The genus identifica¬tion was conducted by using the PCR-amplified sequencing method of 16 S rRNA gene-specific primers, and the in vitro chemosensitivity test was also carried out. The results showed that a total of 182 strains of Aeromonas were iso¬ lated and identified from hepatopancreas, gill filaments and intestinal samples of river crabs, among which Aeromonas veronii accounted for the largest proportion (64%). The results of in vitro chemosensitivity test showed that the isolated strains of Aeromonas from river crabs had the lowest resistance rate to enrofloxacin, only 4.95%, while the sensitivity rate was the highest (86. 81 % ). By comparing the data of drug resistance from 2019 to 2021, it was found that the resistance rate of Aeromonas from river crabs to enrofloxacin has remained at a relatively low level in the past three years. Compared with the other four representative species such as Macrobrachium nipponense, Carassius auratus, Ctenopharyngodon idella and Procambarus shrimp in the aquaculture in Jiangsu Province, the overall condi¬tions of the drug resistance of Aeromonas from river crabs was generally good, and the degree of drug resistance was relatively low. The research results could provide a certain basis for the prevention and treatment of bacterial diseases caused by Aeromonas from river crabs in the region. [ABSTRACT FROM AUTHOR]