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Global climate change has increased concerns regarding biodiversity loss. However, many key conservation issues still required further research, including demographic history, deleterious mutation load, adaptive evolution, and putative introgression. Here we generated the first chromosome-level genome of the endangered Chinese hazelnut, Corylus chinensis, and compared the genomic signatures with its sympatric widespread C. kwechowensis–C. yunnanensis complex. We found large genome rearrangements across all Corylus species and identified species-specific expanded gene families that may be involved in adaptation. Population genomics revealed that both C. chinensis and the C. kwechowensis–C. yunnanensis complex had diverged into two genetic lineages, forming a consistent pattern of southwestern-northern differentiation. Population size of the narrow southwestern lineages of both species have decreased continuously since the late Miocene, whereas the widespread northern lineages have remained stable (C. chinensis) or have even recovered from population bottlenecks (C. kwechowensis–C. yunnanensis complex) during the Quaternary. Compared with C. kwechowensis–C. yunnanensis complex, C. chinensis showed significantly lower genomic diversity and higher inbreeding level. However, C. chinensis carried significantly fewer deleterious mutations than C. kwechowensis–C. yunnanensis complex, as more effective purging selection reduced the accumulation of homozygous variants. We also detected signals of positive selection and adaptive introgression in different lineages, which facilitated the accumulation of favorable variants and formation of local adaptation. Hence, both types of selection and exogenous introgression could have mitigated inbreeding and facilitated survival and persistence of C. chinensis. Overall, our study provides critical insights into lineage differentiation, local adaptation, and the potential for future recovery of endangered trees.

The water resource carrying capacity, as a pivotal component of the overall regional natural resource carrying capacity, plays a fundamental role in determining the feasibility of achieving harmonious coexistence among population, economy, and environment in regions with limited water resources. It holds paramount significance for regional development.“Based on the theoretical framework of the four subsystems, namely water resources, society, economy, and ecology, this article employs the entropy weight method and CRITIC method to calculate individual weights. The combined weights are then determined using game theory. Subsequently, an improved TOPSIS model based on grey relational analysis is applied to comprehensively evaluate the water resources carrying capacity in Gansu Province from 2009 to 2022. The main obstacles impacting water resources carrying capacity are diagnosed using an obstacle degree model. Finally, a time series model is utilized to predict future trends in water resources carrying capacity from 2023 to 2030. The findings suggest that (1)over the study period, Gansu Province exhibited an upward trend in its overall water resource carrying capacity, with a value of 0.55 (weakly bearable) in 2022, representing a significant 20% increase compared to the baseline year of 2009. (2) In terms of regional changes, before 2015, the water resources carrying capacity of Wuwei, Linxia, Dingxi, and other places were in a weakly bearable carrying range [ 0.5,0.6), while other cities and prefectures were in a critical carrying state [ 0.4,0.5). After 2015, the carrying state of most cities and prefectures has improved, especially in Jiuquan, Jiayuguan, Wuwei, and other places, which may be related to the local government’s efforts to increase water resources management and water-saving measures. (3) The key factors influencing the carrying capacity of water resources in Gansu Province include ecological water consumption, industrial wastewater emissions of chemical oxygen demand (COD), urban sewage treatment capacity, effective irrigation area in agricultural land, overall water consumption rate, and per capita daily water consumption in urban areas. To promote sustainable utilization of water resources, it is crucial to strengthen the management and regulation of these major hindering factors. (4) The future carrying capacity of water resources in various cities and states is expected to witness significant improvement. By 2030, it is anticipated that the carrying capacity of all provinces within Gansu Province will reach a bearable state [0.6,1], thereby progressing towards an overall green and sustainable trajectory.

The technology of 3D printing has emerged as a potent tool for the preparation of 3D-printed electrode. Using commercial graphene/polylactic acid (PLA) composite filaments as printed materials, fused deposition modeling as 3D-printed technique, 3D printed electrodes (3DEs) were created in this work. Gold nanoparticles (AuNPs) and the composites of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) were used to modify the activated 3DEs for constructing a novel electrode (SACP@Au@3DE), and in this work chlorogenic acid (CGA) was regarded as a probe for testing the performance of SACP@Au@3DE. The surface physicochemical properties of the prepared 3DEs were characterized by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The electrochemical properties of the prepared 3DEs were investigated using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) methods. The constructed SACP@Au@3DE can be used to determine CGA at concentrations ranging from 10 to 400 μM with a limit of detection (LOD) of 4.13 μM. Ultimately, the SACP@Au@3DE sensor was used for CGA detection in coffee powder sample to explore the potential for real sample analysis. This work opens the novel avenue of using conductive polymer modified 3D-printed electrode in the field of sensor.

Coal is the main energy source in China, and the western region in China is the main coal production area. The protection and utilization of coal mine water is the major technical challenge in the coal mining. The coal green mining research team of China Energy Group has pioneered the technology of underground coal mine reservoirs, which has been widely implemented in the Shendong mining area in Western China, providing over 95% of water needed for mining and ensuring the sustainable development of the mining area. To further enrich and improve the theoretical and technical system of underground coal mine reservoirs, this technology has been promoted and applied under different geological and working conditions in the western coal mining areas to ensure national energy security and water resources protection. The research team has built the original technology experimental platform system for coal mine underground reservoirs, including the comprehensive intelligent experimental platform for underground water transport and protection, the physical modelling platform for coal mine underground reservoirs under multiple coal seams, the dam structure experimental platform for coal mine underground reservoirs, the simulation experimental platform for deep well construction in western areas, the water-rock coupling mechanism experimental platform for underground water reservoirs, the integrated water treatment process experimental platform, and the impact experimental platforms for coal mine underground reservoirs, etc. On these platforms, the researches can be carried out consisting of the transport law of underground water, the optimization of dam structure parameters, the safety and stability of reservoirs, water-rock coupling mechanism, the optimization of mine water treatment, and the impact of caving rock mass on the dam structure under different coal seam occurrence conditions in the western mining areas of China. These platform systems provide a theoretical support and technical verification for the construction, operation, and safety of coal mine underground reservoirs. By utilizing these experimental platforms, various experimental research studies have been conducted, including the stability and seepage of coal mine underground reservoirs under multiple coal seams, the structural safety of coal mine underground reservoirs dam, and the water-rock coupling mechanism of coal mine underground reservoirs. These research results have been applied in actual engineering practice to ensure the safe and stable operation of coal mine underground reservoirs.

The inhomogeneity between cells is the main cause of failure and thermal runaway in Lithium-ion battery packs. Electrochemical Impedance Spectroscopy (EIS) is a non-destructive testing technique that can map the complex reaction processes inside the battery. It can detect and characterise battery anomalies and inconsistencies. This study proposes a method for detecting impedance inconsistencies in Lithium-ion batteries. The method involves conducting a battery EIS test and Distribution of Relaxation Times (DRT) analysis to extract characteristic frequency points in the full frequency band. These points are less affected by the State of Charge (SOC) and have a strong correlation with temperature, charge/discharge rate, and cycles. An anomaly detection characteristic impedance frequency of 136.2644 Hz was determined for a cell in a Lithium-ion battery pack. Single-frequency point impedance acquisition solves the problem of lengthy measurements and identification of anomalies throughout the frequency band. The experiment demonstrates a significant reduction in impedance measurement time, from 1.05 h to just 54 s. The LOF was used to identify anomalies in the EIS data at this characteristic frequency. The detection results were consistent with the actual conditions of the battery pack in the laboratory, which verifies the feasibility of this detection method. The LOF algorithm was chosen due to its superior performance in terms of FAR (False Alarm Rate), MAR (Missing Alarm Rate), and its fast anomaly identification time of only 0.1518 ms. The method does not involve complex mathematical models or parameter identification. This helps to achieve efficient anomaly identification and timely warning of single cells in the battery pack.

The conceptual hydrological model represented by the ABCD model is one of the main methods to quantify and analyze the hydrological cycle processes. However, few studies have examined the physical basis of the variables and parameters of the ABCD model and quantified the relationship between parameters in the conceptual hydrological model and traditional soil hydraulic parameters. In this study, we select the Taigemiao mining area in the Ordos basin as the research site. The HYDRUS-1D software is used to construct the soil-plant-atmosphere continuum (SPAC) model at a site scale for obtaining the “real” actual evapotranspiration during the non-freezing period. The actual evapotranspiration obtained from the SPAC model is considered as the objective function of the ABCD model for calibrating the ABCD model. The soil water storage and soil water leakage simulated by the ABCD model are compared with the results of the SPAC model. The relationships between the parameters of a and b in the ABCD model and the traditional soil hydraulic parameters are analyzed through a large number of scenario simulations. The results show that the ABCD model can better simulate the site-scale monthly actual evapotranspiration and soil water leakage during the non-freezing period. It is indicated that parameter a in the ABCD model has a strong linear correlation with the saturated water content, residual water content and curve shape parameters, while it shows a negative logarithmic relation to the saturated coefficient of permeability. It is also found that parameter b has a strong linear correlation with the saturated water content and curve shape parameter n, while the logarithmic relationships is revealed between parameter b and the saturated coefficient of permeability and curve shape parameter α. This study can improve the understanding of the physical basis of variables and parameters in conceptual hydrological models, and expands the application of hydrological models to hydrogeology.

Abstract Extensive studies have been conducted on the movement of overlying strata when a single coal seam is mined. However, structural characteristics and associated stress field variation of the overlying strata over multiple coal seam mining remain unclear. Here we performed physical modelling experiments analogous to No. 42108 working face of Buertai coal mine, Shendong coalfield, where No. 22 coal seam (2.9 m thickness) was mined first, preceding No. 42 upper coal seam (6.1 m thickness) with an inter-coal-seam distance of 72.8 m. We employed DIC (digital image correlation) measurement and systematically-laid pressure cells to visualize the overlying strata movement and monitor stress field variations over multiple coal seam mining. We found that the stress of the inter-coal-seam strata increased significantly in the late mining stage of No. 22 coal seam due to the strata collapse, and culminated after compaction of the caved blocks. The inter-coal-seam strata stress gradually decreased over mining of No. 42 upper coal seam and arrived at zero after the inter-coal-seam strata collapsed. The mining of No. 42 upper coal seam aggravated the roof settlement of No. 22 coal seam; and the floor stress was noticeably lower than that of No. 22 coal seam due to the pressure-relief caused by the former mining activity. Our physical modelling findings advanced our understanding on structural characteristics and stress evolutions of overlying strata over multiple coal seam mining and offered guidance for prediction and mitigation of strata movement associated disasters in underground coal mining with geomechanical and mining conditions similar to those of Buertai coal mine.

Taigemiao Mining Area is rich in coal resources, but water resources are scarce and the ecological environment is fragile, and the use of hydrogeochemical methods to carry out research on the chemical characteristics and evolution law of groundwater in the whole basin of mining areas can provide scientific support for green mining in mining areas. Piper three-line diagram was used to analyze the types of Cretaceous groundwater, Jurassic groundwater, river water and lake water, and the water chemical characteristics met the characteristics of lake water mixed by river water and evolving groundwater; through Gibbs diagram analysis, it is concluded that the Cretaceous and Jurassic groundwater in the cyclic evolution process It is controlled by rock and evaporation; the ion ratio endmember method further shows that the Cretaceous and Jurassic groundwater is dominated by silicate rock salt and rock salt, accompanied by ion exchange; finally, the mass balance simulation shows that the Cretaceous groundwater circulation During the evolution process, dolomite, gypsum, and rock salt minerals are dissolved, CO2 is absorbed, and calcite is precipitated. With ion exchange, it can be mixed with different proportions of river water to form lake water, but Jurassic groundwater can only be mixed with a small amount of river water or not mixed with river water. The river water accounts for 83% of the water supply of Hongjiannao Lake. Jurassic groundwater cannot be the main source of water supply. The main sources of water in Hongjiannao Lake are Cretaceous groundwater and river water. Combined with the hydrogeological conditions of the mining area, the groundwater flow system of the mining area is divided into the Cretaceous groundwater flow system in the south, the Cretaceous groundwater flow system in the north and the Jurassic groundwater flow system in the deep. Coal mining directly affects the Jurassic groundwater flow system. On the premise of ensuring that the two Cretaceous groundwater flow systems are not damaged, when coal mining drainage only captures the outflow water from the Jurassic boundary or a small amount of Jurassic replenishment to Hongjiannao, coal mining will affect Hongjiannao and surrounding rivers. impact is minimized.

Autolysins are endogenous cell wall degrading enzymes (CWDEs) in bacteria that remodel the peptidoglycan layer of its own cell wall. In the Bacillus subtilis genome, at least 35 autolysin genes have been identified. However, the study of their roles in bacterial physiology has been hampered by their complexity and functional redundancy. B. subtilis GLB191 is an effective biocontrol strain against grape downy mildew disease, the biocontrol effect of which results from both direct effect against the pathogen and stimulation of the plant defense. In this study, we show that the autolysin N-acetylglucosaminidase LytD, a major autolysin of vegetative growth in B. subtilis, plays an important role in its biocontrol activity against grape downy mildew. Disruption of lytD resulted in reduced suppression of the pathogen Plasmopara viticola and stimulation of the plant defense. LytD is also shown to affect the biofilm formation and colonization of B. subtilis on grape leaves. This is the first report that demonstrates the role of an endogenous CWDE in suppressing plant disease infection of a biological control microorganism. These findings not only expand our knowledge on the biological function of autolysins but also provide a new target to promote the biocontrol activity of B. subtilis.

Analysis of the continuous ambient noise data collected by a dense network of broadband seismic stations reveals the characteristics of ambient noise in densely populated urban areas. A study conducted in central Inner Mongolia utilized ten broadband stations to investigate two distinct repetitive and intense noise signals with predominant frequencies ranging from 1-20 Hz and 0.01-1 Hz. The ambient noise within the 0.01-20 Hz frequency range was assessed using Probability Density Function (PDF) and Power Spectral Density (PSD) approaches, and the stations were categorized according to their noise levels. The research results indicate that stations located in urban agglomerations are subject to varying degrees of noise interference, with the main sources of interference being human activities, traffic vibrations, and industrial noise. The impact of high-frequency noise on stations is inversely correlated with the distance from the noise source. Among them, four stations are affected by three noise sources. Three stations are affected by two noise sources, and three stations are affected by one noise source. Therefore, the development of urban agglomerations has brought a large number of noise sources to the stations, which greatly affects the data quality of the stations. This finding urges further investigation on the human activities, traffic vibrations, and industrial noise, and suggests that the station construction should be far away from the urban agglomeration.

Underground reservoir technology for coal mines can realize the coordinated development of coal exploitation and water protection in water-shortage-prone areas. The seepage effect of the floor seriously affects the safety of underground reservoirs under the action of mining damage and seepage pressure. Focusing on the problem of floor seepage in underground reservoirs, a spatial mechanical model of underground reservoirs was established. The main factors affecting the seepage of the surrounding rock were studied. The seepage pressure law in different stages of spatial structure evolution of overlying strata was explored. The results showed that pressure change was the main factor affecting the stability of a reservoir's surrounding rock. The pore space between the broken and fractured rock in the water-flowing fractured zone was the main water storage space, which was directly related to the development of a breaking arch. According to the spatial structure evolution process of the overlying strata, the water storage state of an underground reservoir was divided into two stages and three situations. The seepage pressure was mainly affected by the water pressure and the overlying strata weight. The water pressure was affected by the reservoir head height, and the overlying strata weight was mainly affected by the overlying strata thickness.

During the establishment of the coal mine goaf reservoir, the strength of the coal pillar dam was weakened by various water–rock interactions triggered by water movement. To explore the influence of the water-bearing state on the shear characteristics of coal pillar dams, the 2–2 coal seam of Shangwan Coal Mine in the Shendong Mining area was taken as the research object and was prepared to coal samples with different moisture contents and different drying-saturation cycles, and the variable angle shear test of coal samples was carried out. The law of water absorption of coal samples under natural and pressurized conditions is obtained. The research results show that the shear characteristics of coal samples change significantly under the action of water, with the increase of moisture content and drying-saturation cycles, the lower the shear strength of coal samples is, the larger the peak shear strain is, and the cohesion and internal friction angle of coal samples decrease linearly. According to the relationship between cohesion, internal friction angle, moisture content, and drying-saturation cycle times, the Mohr–Coulomb model of coal samples considering moisture content and immersion times is established, which contributes to the load-bearing capacity estimation of water-bearing coal mass. Additionally, scanning electron microscope analysis revealed significant changes in the microstructure of coal samples under different moisture states: as the moisture content and dry-saturation cycles increase, the microstructure of the coal samples gradually transforms from orderly and compact to disordered and murky, elucidating the mechanism by which moisture weakens the mechanical properties of the coal samples. The research results provide a useful reference for engineering problems related to the stability evaluation of coal bodies involving the repeated erosion effect of water.

BackgroundsNon-vitamin K antagonist oral anticoagulants (NOACs) have been recommended as the first choice over warfarin for non-valvular atrial fibrillation (AF). However, there is limited data about their usage in mainland China.MethodsPrescriptions of patients diagnosed with AF and containing OACs were extracted from Hospital Prescription Cooperation Project from January 2016 to March 2021. The primary outcome was the changing percentage of different OACs. The secondary outcomes were frequencies as well as factors with the choice of different OACs and dosage of NOACs. Univariate and Multivariate logistic regressions were conducted to explore possible factors. All statistical analyses were performed using SAS software (Version 9.4).ResultsAmong the 220,083 distinct prescriptions diagnosed with AF and prescribed with OACs, the percentage of NOACs increased over years, exceeding warfarin in 2018. Until March 2021, 83.53% of included patients were prescribed with NOACs. Rivaroxaban (62.25%) and dabigatran (37.65%) were the most commonly prescribed NOACs. Low dosage was common for NOACs (44.54%), this was mainly driven by rivaroxaban, 67.98% of which were low dosage. Multivariate logistic regression indicated that several factors were positively associated with the preference of low dosage, including outpatients (OR 1.32, 95% CI 1.26–1.39), patients with hypertension (OR 1.49, 95% CI 1.40–1.58), acute coronary syndrome (OR 1.17, 95% CI 1.12–1.22), stroke (OR 1.42, 95% CI 1.33–1.52), and kidney disease (OR 1.63, 95% CI 1.34–1.97), as well as concomitantly using antiplatelet agents (OR 1.52, 95% CI 1.40–1.66), and steroids (OR 1.76, 95% CI 1.50–2.07). On the contrary, they were less common in health insurance holder (OR 0.79, 95% CI 0.75–0.84), patients taking apixaban (vs. rivaroxaban, OR 0.39, 95% CI 0.18–0.81), dabigatran (vs. rivaroxaban, OR 0.01, 95% CI 0.01–0.01), edoxaban (vs. rivaroxaban, OR 0.36, 95% CI 0.23–0.55), diagnosed with heart failure (OR 0.87, 95% CI 0.81–0.93), deep vein thrombosis (OR 0.36, 95% CI 0.29–0.46), pulmonary embolism (OR 0.35, 95% CI 0.28–0.43), and peripheral artery disease (OR 0.68, 95% CI 0.55–0.85).ConclusionThe usage of OACs for AF was overall complying with updated guidelines. Low dosage was common for NOACs, further studies were warranted to verify its effectiveness and explore the underlying mechanism.

Modal parameters are of great significance in civil engineering because they can characterize the properties of structures and be used for vibration control and structural health monitoring. Subway tunnels are long linear truss structures combined with the mutual coupling of the surrounding soil. Therefore, the operational modal analysis of a mutual coupling tunnel is complicate, as is the modal identification of shield tunnels in a time–frequency domain, and these are hot civil engineering topics. Using the shield tunnel of Shanghai metro line No.12 project as a case study, we carried out the vibration response monitoring of a subway tunnel during operation and presented methods to identify structural modal parameters. The modal parameters of lower vibration modes were estimated using response measurements. Modal frequencies and shapes were identified with high precision and accuracy using the orthogonal polynomial clustering algorithm under hammer excitation conditions and the autoregressive-moving-average model under ambient excitation conditions. The dynamic behavior of a mutual coupling tunnel presented obvious low frequency characteristics, and the first 9th order mode frequencies were less than 100 Hz. The diagonal values of the modal assurance criteria were all greater than 0.85. The modal parameters can be used for the health monitoring of operational subway tunnels.

Abstract Background Betulaceae is a relatively small but morphologically diverse family, with many species having important economic and ecological values. Although plastome structure of Betulaceae has been reported sporadically, a comprehensive exploration for plastome evolution is still lacking. Besides, previous phylogenies had been constructed based on limited gene fragments, generating unrobust phylogenetic framework and hindering further studies on divergence ages, biogeography and character evolution. Here, 109 plastomes (sixteen newly assembled and 93 previously published) were subject to comparative genomic and phylogenomic analyses to reconstruct a robust phylogeny and trace the diversification history of Betulaceae. Results All Betulaceae plastomes were highly conserved in genome size, gene order, and structure, although specific variations such as gene loss and IR boundary shifts were revealed. Ten divergent hotspots, including five coding regions (P i > 0.02) and five noncoding regions (P i > 0.035), were identified as candidate DNA barcodes for phylogenetic analysis and species delimitation. Phylogenomic analyses yielded high-resolution topology that supported reciprocal monophyly between Betula and Alnus within Betuloideae, and successive divergence of Corylus, Ostryopsis, and Carpinus-Ostrya within Coryloideae. Incomplete lineage sorting and hybridization may be responsible for the mutual paraphyly between Ostrya and Carpinus. Betulaceae ancestors originated from East Asia during the upper Cretaceous; dispersals and subsequent vicariance accompanied by historical environment changes contributed to its diversification and intercontinental disjunction. Ancestral state reconstruction indicated the acquisition of many taxonomic characters was actually the results of parallel or reversal evolution. Conclusions Our research represents the most comprehensive taxon-sampled and plastome-level phylogenetic inference for Betulaceae to date. The results clearly document global patterns of plastome structural evolution, and established a well-supported phylogeny of Betulaceae. The robust phylogenetic framework not only provides new insights into the intergeneric relationships, but also contributes to a perspective on the diversification history and evolution of the family.

Protected cultivation is currently one of the main cultivation modes for grape production, but the long-term use of plastic film will have a certain negative impact on the light environment in vineyards, which in turn causes poor colouring, low sugar content and a lack of aroma in some red grape varieties. Supplementing light can be an effective way to mitigate these problems. In this study, vines of three red table grape varieties (‘Summer Black’, ‘Xinyu’ and ‘Queen Nina’) cultivated in a plastic greenhouse were supplemented with red, blue, white and red-blue light from veraison to harvest. All four supplemental light treatments increased the content of anthocyanins, sugars and volatile compounds in three grape varieties compared to CK (no supplemental lighting). Red-blue light treatment was the most favourable for the accumulation of anthocyanins and sugars, and the grapes treated with blue light had the highest content of volatile compounds. The grapes treated with red-blue light all obtained the highest composite scores via principal component analysis. For most of the sensory properties, the highest scores were obtained by the red-blue light-treated grapes. The results of this study will be useful in improving the colouring, sugar, and aroma content of grapes under protected cultivation.

The role of coal mine underground reservoirs (CMUR) in ‘guide storage and use’ greatly solves the problem of mine water waste. Replenishment and prediction of reservoir water sources provide an important support for the successful development of key technologies concerning CMUR. To study water replenishment for CMUR, the hydrogeological conditions of the Shendong mining area were investigated as an example. Based on the relationship between the development height of the ‘two belts’ of shallow coal seams and the relative occurrence of location of aquifers, the aquifers are generalized and classified according to occurrences location. Taking Bulianta coal mine as the research background, a discrete element fluid–solid coupling numerical simulation model is constructed to analyze the development characteristics of mining-induced fractures after coal seam mining, and the water replenishment channel of the CMUR is determined. On this basis, analysis is made on the change law of water pressure in the aquifer, aquifuge and coal seam roof under mining action. Taking hydraulic head pressure and water velocity as the judgment basis, prediction and evaluation are made on the water replenishment capacity of CMUR. The research results can provide references for coal mine safety production and mine water protection and utilization. HIGHLIGHTS Based on the water-conducting fractured zone, the occurrence type of ‘coal-water’ is generalized.; The change law of aquifer under different ‘coal-water’ conditions is revealed.; The source and amount of water supply for CMUR were obtained under different conditions.;

Summary: Electrochemical impedance spectroscopy (EIS) is a technique for electrochemical characterization that is sensitive to the battery state and can uncover multidimensional electrochemical evolution information within the battery. Lithium-ion batteries usually need to be used in conjunction with power conversion circuits, while conventional EIS testing is conducted offline and is time-consuming, which cannot effectively monitor the battery characteristics during use. To match the characteristics of the square wave signal during power switching, a rapid EIS measurement method for lithium-ion batteries based on the large square wave excitation signal is proposed in this paper, and develops a testing device with a response time of microseconds. The proposed method and device are applied to estimate the state of health (SOH) of the battery. In conclusion, we proposed method enhances the capabilities of EIS testing technology and has a good application prospect in real-time online impedance monitoring.

The engineering application of cylindrical heat source usually influences the characteristics of the surrounding soil and induces significant coupling responses of temperature, seepage and stress fields. This paper presents a numerical investigation into the thermo-hydraulic-mechanical (THM) coupling behavior of layered soils surrounding a cylindrical heat source by combining the analytical layer element method (ALEM) and the finite element method (FEM). The FEM is utilized to analyze the soil-cylindrical heat source interaction and the ALEM is used to obtain the fundamental solution of the layered soil. Then the THM coupling solution between the heat source and the soil is obtained by the simplified FEM-ALEM coupling method. Detailed validation against experimental result, and verifications against semi-analytical solution and numerical results by Comsol Multiphysics are performed to confirm the robustness of the present method, followed by extensive parametric studies to examine the effects of decaying half-life and type of the time-varying heat source, and the soil layered characteristics on the behavior of soils. It’s evident that the present method is accessible and can be implemented via common programming language, e.g. Fortran.

The electrical and optical properties of a material depend strongly on the details of its crystal structure. Here, the authors report a technique to mechanically deform the lattice of monolayer graphene with strain, and electrically detect the generation of a scalar potential that modifies the graphene work function.

With the rapid development of the smart agriculture in China,the soil moisture monitoring has become particularly important.But there exist many problems in current monitoring methods,such as difficulties in layout and installation,electrode interference,and single monitoring depth.A soil moisture monitor suitable for the farmland was designed.For the hardware structure,a tube-type non-contact design scheme was adopted,and multiple modules were designed in order to realize the layered non-contact monitoring.For the software protocol,a control strategy of the multi-node access based on the Modbus protocol was proposed,which had the characteristics of high polling efficiency,data stability,and wide monitoring nodes.The data was transmitted to the cloud server through the message queuing telemetry transport (MQTT) protocol for the agricultural analysis and decision-making.The test in the vineyard area shows that the monitor can monitor the moisture content in the range of 0~100% and accuracy of ± 2.45%,which is of certain stability and practicality.

Corylus heterophylla and Corylus kweichowensis are economically and ecologically important nut-producing woody shrubs that are distributed across northern and southern regions of China. However, few studies have examined the genetic diversity and genetic relationships between C. heterophylla and C. kweichowensis, and their taxonomic relationships have been questioned. In this study, 796 individuals collected from 34 natural populations (21 C. heterophylla and 13 C. kweichowensis populations) were investigated to assess the genetic diversity and population structure using 11 microsatellite loci. Analysis of molecular variance revealed that genetic differentiation of C. heterophylla and C. kweichowensis within populations accounted for 93.57% and 88.91% of total variation, respectively. The C. heterophylla and C. kweichowensis populations as a whole group were analyzed by multiple programs, which showed that the 34 populations were divided into two genetic clusters. One cluster included 21 C. heterophylla populations, and the second cluster contained 13 C. kweichowensis populations. We conclude from these results that C. heterophylla and C. kweichowensis are distinct species. The Mantel test showed that the genetic distance was significantly correlated with the geographic distance (r = 0.580, P < 0.001). The populations of C. heterophylla [e.g., populations WC (Weichang), MS (Mishan), and WA (Wu’an)] and C. kweichowensis [e.g., populations YX (Yuexi), ZP (Zhenping), LA (Lin’an), and TB (Taibai)] with high allelic richness are considered suitable for in situ conservation. Our study provides valuable information for breeding and conservation of genetic resources of C. heterophylla, C. kweichowensis, and related species.

Abstract Background Farnesol is a sesquiterpene from propolis and citrus fruit that shows promising anti-bacterial activity for caries treatment and prevention, but its hydrophobicity limits the clinical application. We aimed to develop the novel polymeric micelles (PMs) containing a kind of derivative of farnesol and a ligand of pyrophosphate (PPi) that mediated PMs to adhere tightly with the tooth enamel. Results Farnesal (Far) was derived from farnesol and successfully linked to PEG via an acid-labile hydrazone bond to form PEG-hyd-Far, which was then conjugated to PPi and loaded into PMs to form the aimed novel drug delivery system, PPi-Far-PMs. The in vitro test about the binding of PPi-Far-PMs to hydroxyapatite showed that PPi-Far-PMs could bind rapidly to hydroxyapatite and quickly release Far under the acidic conditions. Results from the mechanical testing and the micro-computed tomography indicated that PPi-Far-PMs could restore the microarchitecture of teeth with caries. Moreover, PPi-Far-PMs diminished the incidence and severity of smooth and sulcal surface caries in rats that were infected with Streptococcus mutans while being fed with a high-sucrose diet. The anti-caries efficacy of free Far can be improved significantly by PPi-Far-PMs through the effective binding of it with tooth enamel via PPi. Conclusions This novel drug-delivery system may be useful for the treatment and prevention of dental caries as well as the targeting therapy of anti-bacterial drugs in the oral disease.

The behavior of long-term deformation of saturated soil under external loads has been one of the research focuses in geological engineering and geotechnical engineering. The temperature change, especially in the fields of geological radioactive waste disposal and geothermal system, usually significantly influence the consolidation and creep process of soils. This paper presents an analytical three-dimensional (3D) model for investigating the consolidation and creep behavior of layered soils considering temperature effect. Based on the analytical layer element elastic solution, fractional calculus theory and elastic-viscoelastic correspondence principle, an analytical 3D model is built by introducing the coefficients of thermal expansion and viscosity varying with temperature into the fractional Merchant model (FMM). Verifications against published analytical and numerical results are provided, followed by extensive parametric studies to investigate the effects of type of viscoelastic model, temperature change, fractional order and viscosity of FMM, layered characteristic of soils on consolidation and creep process. It’s evident that the present model predicts long-term behavior of layered viscoelastic soils well and can be used to evaluate the effect of temperature change on consolidation and creep process in geological engineering and geotechnical engineering.

Long-term erosion and repeated scouring of water significantly affect the technical properties of coals, which are the essential elements that must be considered in evaluating an underground reservoir coal column dam’s standing sustainability. In the paper, the coal pillar dam body of the 22 layers of coal in the Shangwan Coal Mine is studied (22 represents No. 2 coal seam), and the water content of this coal pillar dam body is simplified into two types of different water content and dry–wet cycle. Through acoustic emission detection technology and energy dissipation analysis method, the internal failure mechanism of coal water action is analyzed. This study revealed three findings. (1) The crest pressure, strain, and resilient modulus in the coal sample were inversely related to the water content along with the dry–wet cycle number, while the drying–wetting cycle process had a certain time effect on the failure to the sample. (2) As the moisture content and the dry–wet cycle times incremented, three features were shown: first, the breakage pattern is the mainly stretching fracture for the coal specimen; second, the number and absolute value of acoustic emission count peaks decrease; third, the RA-AF probability density plot (RA is the ratio of AE Risetime and Amplitude, and AF is the ratio of AE Count and Duration) corresponds more closely to the large-scale destruction characteristics for the coal samples. (3) A higher quantity of wet and dry cycles results in a smoother energy dissipation curve in the compacted and flexible phases of the crack, indicating that this energy is released earlier. The research results can be applied to the long-term sustainability assessment of the dams of coal columns for underground reservoirs and can also serve as valuable content to the excogitation of water-bearing coal column dams under similar engineering conditions.

Using an abandoned underground goaf in coal mines as water reservoirs has been successfully applied for protecting mine water resources in western China. The water storage media are composed of broken rock masses and the voids between the rock masses. It is critical for reservoir capacity calculation that the deformation characteristics and seepage evolution of the water storage media under triaxial stress are theoretically described. In this study, broken rock masses and the space among the rock masses are simplified as two springs in a series. The mechanical behavior of the broken rock mass is described by Hooke’s law of linear elasticity, and the deformation characteristics of the space among the rock masses are represented by a nonlinear elastic constitutive model. The nonlinear stress-strain constitutive model of the water storage media is established by combining Hooke’s law and the fractional derivative stress-strain model. Similarly, a non-Darcy seepage model of the water storage media is obtained. The nonlinear stress-strain model is verified by mechanical experiments, physical simulation tests, and field measured data, and parameter sensitivity analysis is performed. The non-Darcy seepage equation is fitted and analyzed by using the seepage experimental data of the broken rock mass under triaxial compression conditions. The fractional non-Darcy model rather than the Forchheimer equation can more accurately describe the nonlinear seepage process in water storage media.

The multi-aquifer and multi-aquitard system (MAMA) is a typical geological structure in deltas. Thus, the risks and challenges to settlement control and environmental protection are increased when demand for underground space extends to deeper strata. In this study, dewatering-induced stratified settlement in MAMA is divided into three stages according to whether the overlying aquitard is coupled with groundwater seepage. Subsequently, large physical model tests were carried out. Seepage and compression in the overlying strata come after the compression in the confined aquifer and the coordinated deformation in the overlying strata. The soil is compressed under the seepage drive within the hydraulic gradient range, while the soil above it is still affected by coordinated deformation and shows expansion. Dewatering-induced uneven settlement will cause damage to existing foundations and underground structures. Large-scale and uninterrupted excavation and dewatering are the main reasons for the continuous development of land subsidence. Although artificial groundwater recharging can reduce the settlement of the existing building, underground structure, and surrounding strata, a reasonable space arrangement is needed.

Background: The role of Methylene tetrahydrofolate reductase (MTHFR) C677T and A1298C polymorphisms in the efficacy and toxicity of MTX-based therapy remains uncertain. Our purpose was to clarify whether these two polymorphisms are associated with the outcome of chemotherapy in a cohort of Chinese osteosarcoma (OS) patients treated by high-dose MTX. Methods: 109 OS patients who had sequentially received high-dose MTX therapy were included in this study. Plasma MTX level was measured routinely at 0, 24, 48 and 72 h after the administration of MTX. Two variants of MTHFR were genotyped using TaqMan SNP Genotyping Assay, including rs1801133 (C667T) and rs1801131 (A1298C). The extent of toxicity induced by MTX, including hematological toxicity, hepatic toxicity, renal toxicity and mucositis, was scored from grade 1 to 4. Severe toxicity was defined as a grade score of ≥3. Patients were dichotomized as follows: grade 0.2 µmol/L for plasma MTX level at 72 h. The frequencies of genotypes and allele were compared between the dichotomized groups with the Chi-square test. Results: 24.8% (27/109) of the patients were found to have significantly high plasma MTX level at the 72 h. Patients with high MTX level at 72 h were found to have significantly higher frequency of genotype TT of rs1801133 (p = 0.002). As for rs1801131, no significant association was found with plasma MTX level. Patients with severe hepatic toxicity or mucositis were found to have remarkably higher incidence of genotype TT of rs1801133 than those with mild toxicity (33.3% vs. 14.8%, p = 0.04 for hepatic toxicity; 34.8% vs. 19.8%, p = 0.05 for mucositis). Conclusions: Variant rs1801133 was confirmed to have remarkable influence on the MTX-induced toxicity. We recommend identification of the genotype of MTHFR variant prior to the application of high-dose MTX to OS patients, which could be an important predictor to screen severe toxicities and thus improve treatment outcomes. Keywords: Osteosarcoma, MTX, Variants, MTHFR, Toxicity

Traditional hierarchical control of the microgrid does not consider the energy storage status of a distributed hybrid energy storage system. This leads to the inconsistency of the remaining capacity of the energy storage system in the process of system operation, which is not conducive to the safe and stable operation of the system. In this paper, an improved hierarchical control strategy is proposed: the first allocation layer completes the allocation between the distribution energy storage systems considering the state of hybrid energy storage systems, and the second allocation layer realizes the allocation within the hybrid energy storage systems based on variable time constant low-pass filtering. Considering the extreme conditions of energy storage systems, the transfer current is introduced in the second allocation process. The SOC (stage of charge) of the supercapacitor is between 40% and 60%, which ensures that the supercapacitor has enough margin to respond to the power demand. An example of a 300 MW photovoltaic microgrid system in a certain area is analyzed. Compared with the traditional hierarchical control, the proposed control strategy can reduce the SOC change of a hybrid energy storage system by 9% under the same conditions, and make the supercapacitor active after power stabilization, which is helpful to the stable operation of the microgrid.

In order to solve the problem of which the dynamic response of a supercapacitor (SC) is limited due to the mismatch dynamic characteristics between the DC/DC converter and supercapacitor in an energy storage system, this paper proposes a hybrid model predictive control strategy based on a dual active bridge (DAB). The hybrid model predictive control model considers the supercapacitor and DAB in a unified way, including the equivalent series resistance and capacitance parameters of the SC. The method can obtain a large charging and discharging current of the SC, thereby not only improving the overall response speed of the system, but also expanding the actual capacity utilization range of the SC. The simulation results show that compared with the model prediction method of the dual active bridge converter, the proposed control method can effectively improve the overall response speed of the system, which can be improved by at least 0.4 ms. In addition, the proposed method increases the actual upper limit of the SC voltage, reduces the actual lower limit of the SC voltage, and then expands the actual capacity utilization range of the SC by 18.63%. The proposed method has good application prospects in improving the dynamic response performance of energy storage systems.

In order to reduce the cost and improve the reliability, real-time performance, and installation convenience of remote-controlled light-emitting diode (LED) lighting systems, a networked LED driving technology based on the direct current (DC) grid power line carrier is proposed. In this system, an alternating current (AC)/DC bus converter converts the mains into a DC bus with multiple distributed LED drive powers on the DC bus. The AC/DC bus converter receives the user’s control command and modulates it into the DC bus voltage. The DC bus waveform changes to a square wave containing the high and low changes of the address information and command information. The LED drive power of the corresponding address receives energy from the DC bus and demodulates the commands, such as turning the lights on and off, dimming, etc., and performs the action. In order to make the waveform of the AC/DC bus converter have better rising and falling edge, this paper adopts the half-bridge topology with variable modal control. In the modulation process, the circuit works in buck mode and boost mode. Distributed LED drivers have DC/DC circuits and very simple demodulation circuits that dissipate energy and information from the DC bus. Through experiments, the technology not only simplifies the use of communication technology in application, but also reduces the application difficulty.