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Lake sediments record the environment during the lake sedimentation whose characteristics can infer environmental changes and human activities. In this study, the 210Pb chronologies and sedimentation rate of the sediment core in Honghu Lake were calculated by the Constant Rate of Supply model. The characteristics of the sedimentary environment were analysed by using physical and chemical indicators. Four stages were divided as follows: Stage A (before 1900): The relatively low sedimentation rate and nutrient content indicated an extremely stable sedimentary environment. Stage B (1900–1949): With the growth of population, the intensity of land use began to increase, with an averaged sedimentation rate of 0.252 g·cm−2·a−1. Stage C (1949–1980): The sedimentation rate and nutrient content increased markedly. The intense human activity has damaged the surrounding vegetation leading to soil erosion and accelerated sedimentation rate. With the deterioration of the lake water environment, the organic matter source was mainly the internal source represented by algae and bacteria. Stage D (1980–2011): Influenced by the difference in land use types along the coast, the sedimentation rate of HH-A (0.570 g·cm−2·a−1) is higher than that of HH-B (0.445 g·cm−2·a−1). The results are of significance to the management of rural lakes and reservoirs.

IntroductionVerticillium dahliae causes a serious decline in cotton yield and quality, posing a serious threat to the cotton industry. However, the mechanism of resistance to V. dahliae in cotton is still unclear, which limits the breeding of resistant cultivars.MethodsTo analyze the defense mechanisms of cotton in response to V. dahliae infection, we compared the defense responses of two upland cotton cultivars from Xinjiang (JK1775, resistant; Z8,susceptible) using transcriptome sequencing at different infection stages.ResultsThe results revealed a significant differential expression of genes in the two cotton cultivars post V. dahliae infection, with the number of DEGs in JK1775 being higher than that in Z8 at different infection stages of V. dahliae. Interestingly, the DEGs of both JK1775 and Z8 were enriched in the MAPK signaling pathway in the early and late stages of infection. Importantly, the upregulated DEGs in both cultivars were significantly enriched in all stages of the phenylpropanoid metabolic pathway. Some of these DEGs were involved in the regulation of lignin and coumarin biosynthesis, which may be one of the key factors contributing to the resistance of upland cotton cultivars to V. dahliae in Xinjiang. Lignin staining experiments further showed that the lignin content increased in both resistant and susceptible varieties after inoculation with V. dahliae.DiscussionThis study not only provides insights into the molecular mechanisms of resistance to Verticillium wilt in Xinjiang upland cotton but also offers important candidate gene resources for molecular breeding of resistance to Verticillium wilt in cotton.

The metallurgical changes and micro defects after welding can influence the mechanical property, corrosion resistance and dimensional stability of the stainless steel wielding joints. It is necessary to explore an effective post-welded method to improve the service performance for stainless steel welding joints. Furthermore, the essential mechanism between microstructure changes and macro-property variation during this process needs deep reveal. Therefore, this paper aims at investigating the effects of different post-weld treatments including naturally aging, artificial aging and cryogenic treatment on the residual stress and mechanical properties of 304 stainless steel weldments. The microstructure evolution was also studied to reveal and establish the microstructure-performance relationship. The results showed that the distribution of residual stress was most uniform with lowest magnitude (decreased by up to 49%) after cryogenic treatment. At room temperature, weldments subjected to the three post treatments showed similar mechanical properties. At cryogenic temperature, cryogenic treatment exhibited an outstanding role on maintaining the mechanical properties of weldments. By contrast, the mechanical properties were obviously reduced by artificial aging. The transformation of δ-ferrite and the carbide precipitation in grain boundaries are the main reasons for the decrease of mechanical properties after artificially aging. Welding process was able to cause the transfer of the alloying elements and decrease the stability of austenite. Consequently, martensitic transformation can be induced during cryogenic treatment. The new formed martensite resulted in the refined microstructure and high mechanical properties of weldments, and also the release of residual stress after welding.

In order to accurately assess the risk of the hybrid AC/DC network under fault, a risk assessment method for the hybrid AC/DC system based on the transient energy function is proposed. First, based on the energy transfer relationship of the hybrid AC/DC power system, the transient energy function model of the hybrid AC/DC system is established. Based on the operating data of the power grid, the energy function is used as an efficiency variable, and the efficiency variable is integrated into the prior risk probability calculation of nodes in the network, and a Bayesian network-based risk assessment model of hybrid AC/DC system is established. Considering the dynamic update model of network cascading failures, the clique tree propagation algorithm is used to dynamically calculate the posterior risk probability of the node to realize the dynamic assessment of the network risk. Finally, the improved IEEE-39 node hybrid AC/DC system is used as an example for analysis. The results show that the proposed model can not only effectively evaluate the overall safety of the network, but also has feasibility in predicting faults, which can provide a theoretical basis for the stability control of the hybrid AC/DC system.

Rainfall can cause significant changes in the hydrothermal state within the active layer of the permafrost regions， and the rainfall in the Qinghai-Xizang （Tibet） Plateau has obvious seasonal characteristics.In order to analyze the effects of seasonal rainfall characteristics on the hydrothermal state of permafrost active layer， the meteorological data and the changes of soil heat flux， water content， and temperature within the active layer were monitored in the Beiluhe area of the central Qinghai-Xizang （Tibet） Plateau.The results show that the Beiluhe area is mainly characterized by the light rain events， supplemented by the moderate rain events， and the light rain events accounted for about 90% of the rainfall events from March to November.In addition， the heavy rain events and sustained rain events occur in summer and autumn， respectively.Among them， the rainfall events in each season leads to an overall decrease in surface net radiation， and the impact of the heavy rain events on the net radiation in summer is more obvious.The sustained rain events in autumn lead to a trend of first increase and then decrease in net radiation， and the change trend of soil heat flux consistent with changes in net radiation.Rainfall changes the soil heat flux by affecting the surface net radiation， thus causing changes in the water field and temperature field within soil.Among them， the heavy and moderate rain events in summer can significantly increase shallow soil water content， while spring and autumn rainfall have little effect on soil water content.The effect of the light rain events on soil temperature in each season can be ignored， but the moderate rain， heavy rain and sustained rain events can significantly alleviate the warming trend of shallow soil， and the effect of the rainfall events on alleviating soil warming gradually weakened with the increase of depth.The research results have certain guiding significance for solving regional ecological environment problems and engineering building disease prevention and control problems in permafrost regions.

Electrochemical biosensors have emerged as powerful tools for the ultrasensitive detection of lung cancer biomarkers like carcinoembryonic antigen (CEA), neuron-specific enolase (NSE), and alpha fetoprotein (AFP). This review comprehensively discusses the progress and potential of nanocomposite-based electrochemical biosensors for early lung cancer diagnosis and prognosis. By integrating nanomaterials like graphene, metal nanoparticles, and conducting polymers, these sensors have achieved clinically relevant detection limits in the fg/mL to pg/mL range. We highlight the key role of nanomaterial functionalization in enhancing sensitivity, specificity, and antifouling properties. This review also examines challenges related to reproducibility and clinical translation, emphasizing the need for standardization of fabrication protocols and robust validation studies. With the rapid growth in understanding lung cancer biomarkers and innovations in sensor design, nanocomposite electrochemical biosensors hold immense potential for point-of-care lung cancer screening and personalized therapy guidance. Realizing this goal will require strategic collaboration among material scientists, engineers, and clinicians to address technical and practical hurdles. Overall, this work provides valuable insight for developing next-generation smart diagnostic devices to combat the high mortality of lung cancer.

MXene (Ti3C2Tx) is a promising electrode material for supercapacitors. However, the current MXene material preparation process often requires hydrofluoric acid, and the etched MXene is easily oxidized and stacked, which is not conducive to the transfer of electrons and ions. In this study, we proposed a high concentration of sodium hydroxide solution mixed with sodium hypochlorite solution as an etchant for the preparation of fluorine-free MXene (Ti3C2Tx). Based on the alkali-assisted hydrothermal method, Ti3AlC2 was used as the raw material, and 10 % NaClO aqueous solution was added as the oxidant during the etching process to accelerate the etching and in-situ generate TiO2 with excellent conductivity. When the oxidation time is 12 h and the amount of NaClO is 0.2 mL, the TiO2 particles in-situ generated by the oxidation of Ti element in MXene are evenly distributed on the surface and interlayer of the material, which effectively curbs the stacking problem between the Ti3C2Tx layers and improves the specific surface area of the material. The prepared MXene/TiO2 electrode in 1 M H2SO4 electrolyte, − 0.5–0.2 V voltage window, the highest mass specific capacity can reach 321F/g, and after 10,000 charge–discharge cycles, the capacitance retention rate can still reach 86.4 %, which is higher than the capacitance retention rate of Ti3C2Tx material (81.7 %).

The Augmented Transformer U-Net (AugTransU-Net) is proposed to address limitations in existing transformer-related U-Net models for brain tumor segmentation. While previous models effectively capture long-range dependencies and global context, these works ignore the hierarchy to a certain degree and need more feature diversity as depth increases. The proposed AugTransU-Net integrates two advanced transformer modules into different positions within a U-shaped architecture to overcome these issues. The fundamental innovation lies in constructing improved augmentation transformer modules that incorporate Augmented Shortcuts into standard transformer blocks. These augmented modules are strategically placed at the bottleneck of the segmentation network, forming multi-head self-attention blocks and circulant projections, aiming to maintain feature diversity and enhance feature interaction and diversity. Furthermore, paired attention modules operate from low to high layers throughout the network, establishing long-range relationships in both spatial and channel dimensions. This allows each layer to comprehend the overall brain tumor structure and capture semantic information at critical locations. Experimental results demonstrate the effectiveness and competitiveness of AugTransU-Net in comparison to representative works. The model achieves Dice values of 89.7%/89.8%, 78.2%/78.6%, and 80.4%/81.9% for whole tumor (WT), enhancing tumor (ET) and tumor core (TC) segmentation on the BraTS2019-2020 validation datasets, respectively. The code for AugTransU-Net will be made publicly available at https://github.com/MuqinZ/AugTransUnet.

The two-dimensional thermodynamically consistent phase field model, which consists of the anisotropic Allen-Cahn type equation and the heat equation, is used to study the morphological pattern of the particle in the initial stage of crystal growth. The results reveal the locally reversible growth of the particle in the initial stage of crystal growth. Specifically, some parts of the particle interface first grow inward, while others grow outward from the interface of critical nucleation, until the growth speed of the interface becomes zero. After this, the inward growth parts start to grow outward with other parts. The locally reversible growth of the particle leads to the development of a petal-like shape. The particle radius size dependence of the temperatures along the parts of the particle interface in different crystallographic directions at different time points is studied. By a series of results, the correlations between the morphological pattern selection of the particle and the model parameters, including undercooling and anisotropic strength, are analyzed. These results contribute to understanding the fundamental mechanism of the particle evolution during crystal growth.

Currently, impacts of rapid cropland reclamation and its intense structural changes in internal paddy-upland on ecosystem service are insufficient in Sanjiang Plain, China. Further, land management systems of Sanjiang Plain consist of state-owned and private farms; however, exploring the impact of different land management systems on “land use–landscape–ecosystem service” is still lacking. To reveal this issue, the integrated methodology of “land dynamic tracking–landscape index–improved ecosystem service assessment” was established. Results are displayed below: From 1990 to 2020, land use was featured by decreases in forest (−3308.62 km2), grassland (−6030.86 km2), waters (−475.81 km2), and unused land (−3037.27 km2), with a slight increase in constructed land (+403.25 km2) and a rapid increase in cropland (+12,447.56 km2). Although nearly equal increments of cropland on state-owned and private farms (i.e., 6156.70 km2 vs. 6290.86 km2) were monitored, different cropland structure changes were still revealed, namely a drastic expansion of paddy fields (13,788.32 km2) and an acute decrease in upland crops (−7631.62 km2) on state-owned farms, but both a slight increments in paddy fields (5920.08 km2) and upland crops (370.78 km2) on private farms. For landscape, private farms were more fragmented (SHDI = +0.63%), causing a decrease in aggregation (AI = −0.56%) and a more complex shape (LSI = +23.3%), by contrast, state-owned farms displayed an increased integrity (SHDI = −9.88%), along with an increase in aggregation (AI = +0.43%) and simplified shape (LSI = −13.30%). Evaluated ecosystem service value changed from 338.62 to 296.25 billion yuan from 1990 to 2020, a loss rate of 12.58% in Sanjiang Plain. Then, a new finding showed a higher loss rate on state-owned than private farms (i.e., 30.15% vs. only 6.18%). This study revealed differentiated processes of “land use–landscape–ecosystem service” in different land management system regions in China, providing new findings in the fields of land management system, ecological landscape, and environment.

IntroductionAutism Spectrum Disorder (ASD) has a significant impact on the health of patients, and early diagnosis and treatment are essential to improve their quality of life. Machine learning methods, including multi-classifier fusion, have been widely used for disease diagnosis and prediction with remarkable results. However, current multi-classifier fusion methods lack the ability to measure the belief level of different samples and effectively fuse them jointly.MethodsTo address these issues, a multi-classifier fusion classification framework based on belief-value for ASD diagnosis is proposed in this paper. The belief-value measures the belief level of different samples based on distance information (the output distance of the classifier) and local density information (the weight of the nearest neighbor samples on the test samples), which is more representative than using a single type of information. Then, the complementary relationships between belief-values are captured via a multilayer perceptron (MLP) network for effective fusion of belief-values.ResultsThe experimental results demonstrate that the proposed classification framework achieves better performance than a single classifier and confirm that the fusion method used can effectively fuse complementary relationships to achieve accurate diagnosis.DiscussionFurthermore, the effectiveness of our method has only been validated in the diagnosis of ASD. For future work, we plan to extend this method to the diagnosis of other neuropsychiatric disorders.

The effects of post-weld aging and cryogenic treatment on self-fusion welded austenitic stainless steel thick plates were investigated in the present work. The results showed that fusion zone microstructure consisted of austenite matrix and vermicular ferrite. Aging treatment promoted the decomposition of δ-ferrite into σ-ferrites as well as the precipitation of carbides. Isothermal martensitic transformation in the Tungsten Inert Gas Welding (TIG) specimen was induced by cryogenic treatment, and stacking faults were increased. The fusion zone microstructure of Electron Beam Welding (EBW) and Laser Welding (LW) was finer than that of TIG, with acicular ferrite distributed in the austenite matrix. A large number of twins were generated in the austenite matrix after LW. Cryogenic treatment produced a large number of sub-grains in LW specimens, which was due to the entanglement and accumulation of dislocations in the vicinity of ferrite. Post-weld aging and cryogenic treatment have no influence on the strength of weldments with different welding methods while cryogenic treatment could improve the impact toughness of EBW and LW weldments by the extent of 7.4% and 8.8%, respectively. The aging treatment reduced the impact toughness by 49%, 33% and 15.5%, as well as the uniform elongation by 44%, 39% and 17% for TIG, EBW and LW, respectively. Aging treatment reduced the surface residual stress of TIG weldment by 58.8% in Y direction and 61.2% in X direction. Cryogenic treatment at could also release the surface residual stress of TIG weldment by 36.8% in X direction and 16.3% in Y direction.

Study region: This study interrogates a landslide in ice-rich permafrost region in the Eastern Qinghai–Tibet Plateau, China. Study focus: Climate warming has increased the frequency and intensity of rainfall events, changing hydrothermal processes and the soil mechanical properties, thus affecting slope stability in permafrost region. The purpose of this paper is to elucidate the variations in soil volumetric water content (VWC) which may influence the mechanical properties of unstable slopes in ice-rich permafrost region under different rainfall conditions. New hydrological insights for the region: This paper integrates the rainfall infiltration boundary conditions and Mohr–Coulomb criterion into a thermo–hydro–mechanical (THM) model and analyzes a landslide case in the permafrost regions. The results show that the THM model can effectively account for the impacts of VWC variation under different rainfall conditions. The influence of rainfall on the VWC diminishes as depth increases, with a more pronounced effect observed at depths less than 1 m. At depths exceeding 1 m, the impact is relatively minor. Under the condition of low-intensity, long-duration rainfall, with accumulated precipitation exceeding 60 mm, the cohesion and internal friction angle decrease to 4.2kPa and 8.1°, respectively, with a deep-layer integral slippage. In contrast, under the condition of high-intensity, short-term rainfall, the accumulated rainfall exceeds 75 mm and the internal friction angle decreases from 39° to 26°, with shallow-layer slippage. The results add on to our understanding engineering problems and periglacial geomorphic processes under the influence of climate warming.

Supply chain coordination has been a research hot spot in supply chain management. This paper constructs a secondary supply chain system. Taking the abatement of the bullwhip effect and the double marginal effect as the coordination objective, a simulation study of supply chain decision coordination was conducted using system dynamics. First, by controlling the lead time, it was found that in the decentralized decision-making model, the profit of the supplier and the whole supply chain increases with the shortening of the lead time, and vice versa for the retailer. In the centralized decision-making model with the addition of information sharing and contract, it was found that the retailer’s profit is consistent with the trend of the supplier and the supply chain as a whole, and the supplier’s profit is lower than that of decentralized decision making in the pre-cooperation period. In addition, it is also found that adjusting the contract parameters can effectively improve the situation. Finally, the above models were analyzed for supply chain coordination decisions based on two scenarios: “cooperative stability” or “balance of effects”.

In recent years, significant oil and gas discoveries have been achieved in the Permian Upper Wuerhe Formation and the Triassic Baikouquan Formation on the marginal slope of oil generation sag, Junggar Basin. However, in the central sag of the basin, no oil or gas show has been discovered in target formations, and low production has been made only by two wells. As a result, it is necessary to deepen the understanding of the mechanisms of oil and gas accumulation and clarify the main controlling factors. The analyses of the accumulation conditions in the central sag and some wells show that the direct reason for the failure to find oil and gas in the sag is the lack of local source-connecting faults and poor reservoir properties. An accumulation model with source in the lower section and reservoir in the upper section controlled by both source-connecting faults and favorable sand bodies was established for the Permian and Triassic strata in the sag. The sandbody lithologic reservoirs of fan-delta front subfacies in the Upper Wuerhe and Baikouquan formations under the background of stratigraphic overlap are the primary direction of exploration, covering an area about 3 600 km2. The comprehensive exploration of unconventional oil and gas in the Middle-Lower Permian source rocks and conventional oil and gas in multiple layers outside the source area should be targeted.

Carbon molecular deposition in sediments removes organic carbon (OC) from the biosphere-atmosphere carbon cycle and therefore limits the emission of greenhouse gases (i.e. CH4 and CO2) from natural water systems. At present, the occurrence characteristics, deposition fluxes, and driving force of OC components in the river-lake ecotone are unclear. Here, the tempo-spatial distribution of polycyclic aromatic hydrocarbons (PAHs) and Σn-alkanes (nC13–nC32) related to organic nitrogen (ON) and OC in the estuarine sediments from Poyang Lake and their sources and effects were investigated. The ON and OC contents in the sediment cores ranged from 0.35−0.64 % and 1.9–4.24 %, respectively, and the PAH fluxes varied between 672.19 and 24703.97 ng cm−2 a-1, showing an upward risk to the water bodies and human health. In particular, it is worth noting that the 5–6 ring monomers were dominant, accounting for 66.48 % of the ΣPAHs in the sediment profile. The sources were mainly derived from biomass combustion and automobile exhaust emissions, while the latter proportion has increased in recent decades. In the sediment profile, the n-alkane abundance peak was found at nC31 with a marked odd-even predominance. The deposition flux for Σn-alkanes ranged between 10.92 and 73.46 μg cm−2 a-1. In addition, long-chain monomers dominated the Σn-alkanes and were found to be herbaceous in origin. An analysis of the environmental indicators in the sediment layers showed that forest restoration and the eutrophication of water bodies caused by anthropogenic stress and climate change were mainly responsible for the relatively large contribution made by vascular plants and autochthonous organisms.

Abstract To study the spatial occurrence, sources, and ecological risks of 16 PAHs, surface sediments had been collected from seven major areas of Taihu Lake, China in April 2021. Results showed that the concentrations of ∑16PAHs varied between 1381.48 and 4682.16 ng g−1, and the contents of BghiP in each sample were the highest. The PAHs concentrations in the sediments near the lakeshore were much higher than those in the central area of the lake. The sedimentary ∑16PAHs were mainly composed of molecular-weight monomers and 4-ring PAHs showed superiority (35.69–45.02%). According to the ratio of PAH monomer, the sedimentary PAHs in Taihu Lake were dominantly derived from the combustion. Through the biological toxicity assessment and the BaP equivalent (BaPE), great biological risks of PAHs monomers i.e. DahA and IcdP were found. Both concentrations of ∑16PAHs and dominant 4–6-ring monomers accompanied by carcinogenic risks in many areas of Taihu Lake increased. It is necessary to strengthen monitoring and take measures to control the input of organic pollutants.

ABSTRACT Under the influence of large temperature differences in an impermeable pavement layer of wide embankment in permafrost regions, liquid water accumulates at the bottom of the impermeable cover. The phenomenon is known as the pot‐cover effect and leads to an increase in soil water content and a reduction in bearing capacity of wide embankments. At present, water vapor and liquid water migrations and their effect on embankment thermal‐moisture stability have not been fully confirmed. To better understand the moisture transport and accumulation process within embankments, hydrothermal field monitoring was conducted from 2009 to 2011 on an asphalt concrete layer highway in Beiluhe, central Tibet Plateau. The field monitoring results show that soil moisture content between 50 and 250 cm below the pavement continuously increases with the number of freeze‐thaw cycles, with the largest increase during the 2 years being 6.4%. Then, a coupled hydro‐vapor‐thermal transport model was established and verified. Furthermore, the model was used to analyze the numerical recurrence of the pot‐cover effect. The simulation indicates that the upward migration of liquid water during the freezing period is less than the downward migration during the thawing period, while vapor migrates downward during the thawing period but upward during the freezing period. The migration of water vapor within the embankment during the freezing period is the main cause of the pot‐cover effect in permafrost regions. In addition, the research results can provide new ideas for understanding the internal mechanism of thermal‐moisture dynamics of the embankment and the stability prediction of permafrost engineering. [ABSTRACT FROM AUTHOR]

Rapid advancements in construction technologies have accelerated the development of complex and deep underground structures, raising concerns about the impact of groundwater on structures, particularly anti-floating measures. Traditional tensioned anchors, commonly used for preventing flotation, suffer from limitations like low pull-out bearing capacity, shallow critical anchoring depth, and localized stress concentration. To overcome these limitations, this paper introduces a tension–compression dispersed composite anchor, which combines casing, load-bearing plates, and tensioned anchors. Comparative tests were conducted between these composite anchors and traditional tensioned anchors to analyze their anchoring behavior. Our results show that tensioned anchors exhibit a stable axial force distribution as anchoring length increases. By identifying abrupt changes in the axial force curve, optimal anchoring lengths for load-dispersed anchors can be determined, thereby enhancing rock and soil strength utilization. The tension–compression-dispersed composite anchor outperforms tensioned anchors, with 1.44 times the ultimate bearing capacity for equivalent anchoring lengths and 1.1 times the capacity for an additional 1 m length. It also displays superior deformation adaptability and structural ductility under high-bearing loads compared to tensioned anchors with extended anchoring lengths. Effectively mobilizing the strength of the lower anchoring segment within the rock and soil results in a lower critical anchoring depth and a more uniform distribution of lateral friction resistance. In conclusion, the tension–compression-dispersed composite anchor offers significant advantages, making it a promising engineering solution for anti-floating anchor systems in complex underground environments.

We consider the Cox–Ingersoll–Ross (CIR) model in time-dependent domains, that is, the CIR process in time-dependent domains reflected at the time-dependent boundary. This is a very meaningful question, as the CIR model is commonly used to describe interest rate models, and interest rates are often artificially set within a time-dependent domain by policy makers. We consider the most fundamental question of recurrence versus transience for normally reflected CIR process with time-dependent domains, and we examine some precise conditions for recurrence versus transience in terms of the growth rates of the boundary. The drift terms and the diffusion terms of the CIR processes in time-dependent domains are carefully provided. In the transience case, we also investigate the last passage time, while in the case of recurrence, we also consider the positive recurrence of the CIR processes in time-dependent domains.

Carbon burial in lake sediments has a profound impact on the global carbon cycle. In this study, the burial characteristics of organic carbon (OC) in typical sediments from the Poyang basin over the past hundred years were investigated and the influencing factors and driving mechanism were determined. The results showed that carbon burial in the Poyang basin sediments was mainly driven by human activities, whereas the change in the OC accumulation rate was related to precipitation, forest land area, water area, construction land area, urbanization rate, application of agricultural fertilizers, per capita GDP and population.

(1) Objective: to accelerate the digitalization of the elderly care service industry and the construction of the smart elderly care industry, this paper designs an intelligent e-procurement system for elderly suppliers selecting from the perspective of smart elderly care, which can enhance the efficiency of elderly care supply chains and assist manufacturers of elderly products in choosing a reliable, high-quality supplier during trades. (2) Methods: the e-procurement system, including six modules, is built with an improved dynamic Markov Decision Process selection model combined with an Analytic Network Process, bringing dynamic evolution of both inventory cost and purchasing cost into long-term reward calculation, and taking into account 15 common indexes and 7 specific indexes when evaluating suppliers’ competitiveness. (3) Results: a real sample shows that when facing 50 suppliers with 50 different quotations, the e-procurement system selects a stable and reliable supplier that brings the best long-term profits for demand enterprises in ten purchase periods, and it makes the selecting process more efficient and more prompt. (4) Conclusions: the model can be used in the circumstance where an elderly product producer is forced to decide on a long-term strategy or reselect a new stable supplier since it is focused on choosing long-term and high-quality suppliers over numerous periods.

The rapid economic development in the Yangtze River Delta has affected the carbon (C) pool in lake sediments, which has become a serious environmental management issue. To explore the characteristics of composition, spatial distribution and burial of organic C (OC) in lacustrine sediments, a typical shallow lake was targeted to compare the heavy fraction OC (HFOC), light fraction OC (LFOC), and dissolved OC (DOC) in the surface sediments of different lake areas using the specific gravity separation approach. The effects of environmental factors on the form of OC present were identified by a redundancy analysis. The results showed a regional difference of DOC, LFOC, and HFOC concentrations in Taihu Lake, and HFOC was dominant in the OC buried in lake sediments. The deposition rate of OC in Taihu Lake sediments varied in a ranged of 31.91–114.47 g C m−2 a-1. The LFOC levels in the sediments were lower than those in other lakes. Both sedimentary LFOC and HFOC were significantly correlated with the nitrogen (N) content, indicating that the C sink was enhanced by an increase in N in the sediments. The grass-type lake zone stimulated C accumulation in Taihu Lake sediments.

Objective: To investigate the clinical utility of ultrasound-guided balloon occlusion in cesarean section in patients with sinister placenta previa. Methods: The Interventional and Ultrasound Departments of the authors’ center assisted obstetrics to complete cesarean section in cases of sinister placenta previa. A total of 130 patients with implanted sinister placenta previa were diagnosed using obstetrical ultrasound and magnetic resonance imaging (MRI). Before cesarean section, the balloon was positioned in the bilateral radial or abdominal aorta. Immediately after delivery of the fetus, the balloon was temporarily filled to transiently seal the target vessel. According to the obstetrician’s assessment of hemostasis, the balloon was withdrawn at the appropriate time. Among the 130 patients, there was one case of abdominal aortic occlusion, with 129 cases blocked by the bilateral common iliac artery. Results: All 130 cases were successfully blocked, with an average blocking time of

To improve the visual quality of noisy medical images acquired by low radiation dose imaging, medical image denoising is highly desirable for clinical disease diagnosis. In this paper, a geometric regularization method is proposed for medical image denoising. To the best of our knowledge, this is the first work aiming at reconstructing surface by minimizing the gradient error and approximation error of the surface to suppress the noise in medical images. The proposed denoising method consists of two stages: one is to output a basic estimate and the other is for the residual noise reduction. Specifically, the method first exploits a biquadratic polynomial surface to generate an initial estimate of the noise-free image. The surface is constructed by dividing its coefficients into two groups. With the reconstruction error constraint, one group is used to minimize the gradient of the surface, and the other is to minimize the approximation accuracy of the surface. Then the residual noise in the initial result is further reduced by using the singular value thresholding mechanism, which exploits the self-similarity of medical images and the intrinsic low-rank property. Unlike the traditional truncated singular value thresholding scheme, the proposed singular value thresholding is derived by optimizing an objective function with a constraint. Experimental results on a real clinical data set demonstrate the effectiveness of the proposed denoising method, especially in detail-preserving. Compared with several widely used denoising methods, our method can achieve a better performance in terms of both quantitative metrics and subjective visual quality.

Convolutional neural networks (CNNs) require large amounts of data for training, beyond what can be acquired for current radiomics models. We hypothesize that deep entropy features (DEFs) derived from existing CNNs can be applied to MRI images of prostate cancers (PCa) to reliably predict the Gleason score (GS) of PCa lesions. In this study, we analyzed 112 lesions acquired from 99 PCa patients, either pre-biopsy or pre-treatment, their associated GS, and multi-parametric MRI (mpMRI) sequences. Our approach is based on the extraction of DEF features produced in individual layers of 9 pre-trained CNN models. We first analyze DEFs from separate CNNs using the Wilcoxon test and Spearman correlation to find significant features associated with GS. In a multivariate analysis, we then use the combined DEFs of all CNNs as input to a random forest (RF) classifier for predicting the Gleason grade group of patients. Among the 9 pre-trained CNNs, the NASNet-mobile architecture offered the features most correlated to GS ( $\rho =0.47$ ; p < 0.05). From the 7,857 combined features, 11 DEFs could differentiate GS < 8 from GS ≥8 (corrected p < 0.05). Moreover, the RF classifier discerned GS of 6, 3+4, 4+3, 8 and ≥9 with an AUC (%) of 80.08, 85.77, 97.30, 98.20, and 86.51, respectively. Our results suggest that the DEFs can be used to differentiate GS of PCa lesions with the highest accuracy of GS ≥8 based on mpMRI. DEFs could improve diagnosis accuracy, reduce the risks of misclassification, help to better assess prognosis, and individualize patient care approaches.

The regional multi-energy system (RMES) can realize the coupling and complementation of different energy sectors, including electricity, heat, and gas, with the advantage of energy cascade utilization. With the development of hydrogen fuel cell vehicle (FCV) technology, hydrogen has great application potential in the transportation sector. The use of surplus electricity to produce hydrogen through water electrolysis technology can increase renewable energy penetration in power systems. This paper proposed an optimal design and operation method of RMES that considers system reliability constraints under different-level renewable energy penetrations. The RMES includes renewable generation devices, conversion devices such as fuel cells and electric boilers, and emerging devices such as electrolysis cells and hydrogen storage tanks. In order to improve the reliability of the planning results, we consider the reliability constraints of crucial devices in the planning model. In addition, we paid attention to the potential of hydrogen storage tanks for inter-seasonal energy complementation. In the solution of the model, the optimization model can be transformed into a mixed-integer linear programming (MILP) problem by linearizing the non-linear constraints, which can be directly solved by CPLEX, showing good performances in practical applications. Finally, case studies are performed to show the superiority of the planning model.

This paper focused on three application problems of the traditional Deep Deterministic Policy Gradient(DDPG) algorithm. That is, the agent exploration is insufficient, the neural network performance is unsatisfied, the agent output fluctuates greatly. In terms of agent exploration strategy, network training algorithm and overall algorithm implementation, an improved DDPG method based on double-layer BP neural network is proposed. This method introduces fuzzy algorithm and BFGS algorithm based on Armijo-Goldstein criterion, improves the exploration efficiency, learning efficiency and convergence of BP neural network, increases the number of layers of BP neural network to improve the fitting ability of the network, and adopts periodic update to ensure the stable operation of the algorithm. The experimental results show that the deep learning network based on the improved DDPG algorithm has greatly improved the performance compared with the traditional method after multiple rounds of self-learning under variable working conditions. This study lays a theoretical and experimental foundation for the extended application of deep learning algorithm.