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Embedding soft soil particles with high moisture content into miscellaneous fill with large pores under overlying loads is easy. It produces mutually embedded settlement, which is an important component of total foundation settlement during calculation. In this study, influences of interface friction on mutually embedded settlement, particle displacement, pore and contact characteristics, and mutually embedded development laws were analysed by using the particle flow method. Research results demonstrate that mutually embedded settlement decreases first and then stabilizes with the increase in contact friction factor and continuously attenuates with normal stiffness. Under the loads, particles at the contact surface move downward and squeeze surrounding particles laterally, thus causing particles to slide at the miscellaneous fill channel upward. Consequently, porosity of particles in miscellaneous fill channel increases. The force chain at the contact surface inclines around, while that at the miscellaneous fill channel presents approximately horizontal distribution. Compared with 35 and 45 mm particles, the mutually embedded settlement of 15 and 25 mm particles is slightly increased with loads. Particle size can relieve the influences of loads on mutual embedding. When particle size is larger than 25 mm, loads can significantly influence mutual embedding. Research conclusions can provide a reasonable theoretical foundation for calculating or predicting settlement of miscellaneous fill-soft soil composite foundation.

Additional file 1: Figure S1. The country network of Spain. Figure S2. The country network of Italy. Figure S3. The country network of Netherlands. Figure S4. The regional network of Parts of Europe. Figure S5. The early signals of COVID-19 in Netherlands and Spain.

Remote sensing has been used as an important tool for disaster monitoring and disaster scope extraction, especially for the analysis of spatial and temporal disaster patterns of large-scale and long-duration series. Based on the Google Earth Engine cloud platform, this study used MODIS vegetation index products with 250-m spatial resolution synthesized over 16 days from the period 2005–2019 to develop a rapid and effective method for monitoring disasters across a wide spatiotemporal range. Three types of disaster monitoring and scope extraction models are proposed: the normalized difference vegetation index (NDVI) median time standardization model (RNDVI_TM(i)), the NDVI median phenology standardization model (RNDVI_AM(i)(j)), and the NDVI median spatiotemporal standardization model (RNDVI_ZM(i)(j)). The optimal disaster extraction threshold for each model in different time phases was determined using Otsu’s method, and the extraction results were verified by medium-resolution images and ground-measured data of the same or quasi-same period. Finally, the disaster scope of cultivated land in Heilongjiang Province from 2010–2019 was extracted, and the spatial and temporal patterns of the disasters were analyzed based on meteorological data. This analysis revealed that the three aforementioned models exhibited high disaster monitoring and range extraction capabilities, with verification accuracies of 97.46%, 96.90%, and 96.67% for RNDVI_TM(i), RNDVI_AM(i), and (j)RNDVI_ZM(i)(j), respectively. The spatial and temporal disaster distributions were found to be consistent with the disasters of the insured plots and the meteorological data across the entire province. Moreover, different monitoring and extraction methods were used for different disasters, among which wind hazard and insect disasters often required a delay of 16 days prior to observation. Each model also displayed various sensitivities and were applicable to different disasters. Compared with other techniques, the proposed method is fast and easy to implement. This new approach can be applied to numerous types of disaster monitoring as well as large-scale agricultural disaster monitoring and can easily be applied to other research areas. This study presents a novel method for large-scale agricultural disaster monitoring.

Negative vacuum pressure hardly reaches deep soils due to the drain board bending and serious blockage with the existing vacuum preloading methods (VPMs), thus resulting in poor reinforcement relative to practical engineering applications. To address this issue, this paper proposes a vacuum preloading method with pumping and discharging (a new dredger filling foundation processing technique based on vacuum preloading). This new VPM is developed through technological improvement and plastic drain board innovations in traditional VPMs. The new VPM uses a plastic vertical drainage board with double drainage channels, and the core board is in a “tic-tac-toe” shape with a hollow centre and square pipeline channels. It can execute air and water drainage. Vacuum transfer holes were set at two grooves, every 2-3 m from the central pipeline of the core board. Grooves at two sides of the core board and filter membrane were rolled together to improve drainage. In addition, the vacuum pipe, tube connector, and core board centre of the vertical plastic drainage board were connected directly and securely. A stereoscopic vacuum transmission system composed of a horizontal and vertical drainage system was built. In this vacuum transmission system, the transfer route was shortened, and the loss of vacuum along the route was decreased. The negative vacuum pressure was transferred to different soil depths through the central pipeline of the core board to accelerate the dissipation of pore pressure in soil mass and prevent vacuum pressure loss caused by drainage board bending, thus improving the reinforcement effect. Dredger filling silt foundation reinforcement by VPM and VPM with pumping and drainage were compared in laboratory simulations and field tests with different drainage boards. Test results show that the loss of vacuum pressure along the drainage path was relatively smaller in the new physical vapor deposition (PVD), and the pressure transfer efficiency was increased. Deep soil mass was reinforced effectively by using the new PVD. After reinforcement, the physical and mechanical properties of soil layers were improved. Moreover, soil strengths were remarkably improved, with sharp reductions in natural moisture content and porosity. Then, the transfer law of vacuum on different drainage boards and the reinforcement mechanism of VPM with pumping and drainage were analysed. Research conclusions show the superiority of VPM with pumping and drainage in terms of effectiveness and soft foundation reinforcement. This study provides a theoretical basis for the application and development of the new VPM.

Objective. A systematic review of randomized trials was performed to assess the effect of Ginkgo Biloba Dropping Pills (GBDP) on clinical hemorheology and blood lipid indicators. Methods. The data of the Embase, Cochrane Library, PubMed, Clinical Trials, China National Knowledge Infrastructure, the Wanfang database, the VIP database, and the Sinomed were retrieved by computers from the establishment of the database to March 27, 2018, and screened and extracted by two researchers according to inclusion and exclusion criteria. Cochrane 5.0 recommended bias risk assessment tool was used to evaluate the methodological quality of the included literature, and Revman 5.3 software were used for meta-analysis. Results. 10 literatures were finally selected in accordance with the standard. There were a total of 1201 cases, 608 cases in ginkgo biloba dropping pill group and 593 in routine treatment group. Compared with control group, GBDP significantly improved plasma viscosity [N=383, RR= - 0.45, 95%CI=(-0.86,-0.04), P=0.03], whole blood high shear [N=232, RR= - 0.92,95%CI=(-1.69, -0.16), P =0.02], whole blood low shear [N = 232, RR = - 2.22, 95% CI = (- 3.74, -0.7), P = 0.004], red blood cell specific volume [N =132, RR = - 4.55, 95% CI = (- 6.36, 2.73), P < 0.000 01], fibrinogen [N=243, RR=-0.60,95%CI=(-0.82,-0.39), P

Matrine, is a bioactive compound isolated from Sophora flavescens (Ku shen), an herb used in Chinese traditional medicine that possesses wide-reaching pharmacological action. Psoriasis is a chronic relapsing inflammatory disorder with an incompletely understood pathophysiology, and dendritic cells (DCs) play a central role in the disease. This study aimed to explore DCs related potential mechanisms based on the effect of matrine on imiquimod (IMQ)-induced psoriasiform dermatitis in BALB/c mice and DCs simulated by resiquimod. Mice with IMQ-induced psoriasiform cutaneous lesions were treated with matrine [12.5, 25 or 50 mg/(kg·d), for 6 days]. Morphology, histological changes, keratinocyte proliferation and differentiation, inflammatory cell infiltration, protein expression levels of myeloid differentiation factor 88 (MyD88), and mRNA expression levels of inflammatory factors [interleukin (IL)-12, IL-23, and IL-1β] in lesional skin were assessed. The application of matrine decreased the proliferation of IMQ-induced keratinocytes. The treatment attenuated the infiltration of PCNA(+) and CD3(+) cells in the lesions. Matrine reduced the expression of the MyD88 protein and the inflammatory factors’ mRNA in lesional skin, but also in BMDCs (bone marrow derived dendritic cells). These results indicated that matrine suppressed expression of the inflammatory factors by decreasing the expression of the MyD88 protein on the surface of BMDCs, finally alleviating psoriasiform skin lesions. Therefore, the findings suggest that matrine might be a potential candidate for treating psoriasis.