•COVID-19 is spreading fast with an increasing number of infected patients worldwide.•This review summarizes the epidemiology, clinical characteristics, diagnosis, treatment and prevention of ...COVID-19.•The specific mechanism of the virus remains unknown, and specific drugs for the virus have not been developed to date.
COVID-19, the disease caused by SARS-CoV-2, is a highly contagious disease. The World Health Organization has declared the ongoing outbreak to be a global public health emergency. Currently, the research on SARS-CoV-2 is in its primary stages. Based on current published evidence, this review systematically summarizes the epidemiology, clinical characteristics, diagnosis, treatment and prevention of COVID-19. It is hoped that this review will help the public to recognize and deal with SARS-CoV-2, and provide a reference for future studies.
Lignin is one of the main components of plant cell wall and it is a natural phenolic polymer with high molecular weight, complex composition and structure. Lignin biosynthesis extensively contributes ...to plant growth, tissue/organ development, lodging resistance and the responses to a variety of biotic and abiotic stresses. In the present review, we systematically introduce the biosynthesis of lignin and its regulation by genetic modification and summarize the main biological functions of lignin in plants and their applications. We hope this review will give an in-depth understanding of the important roles of lignin biosynthesis in various plants' biological processes and provide a theoretical basis for the genetic improvement of lignin content and composition in energy plants and crops.
Diabetic nephropathy (DN) together with glomerular hyperfiltration has been implicated in the development of diabetic microangiopathy in the initial stage of diabetic diseases. Increased amounts of ...urinary protein in DN may be associated with functional and morphological alterations of podocyte, mainly including podocyte hypertrophy, epithelial-mesenchymal transdifferentiation (EMT), podocyte detachment, and podocyte apoptosis. Accumulating studies have revealed that disruption in multiple renal signaling pathways had been critical in the progression of these pathological damages, such as adenosine monophosphate-activated kinase signaling pathways (AMPK), wnt/β-catenin signaling pathways, endoplasmic reticulum stress-related signaling pathways, mammalian target of rapamycin (mTOR)/autophagy pathway, and Rho GTPases. In this review, we highlight new molecular insights underlying podocyte injury in the progression of DN, which offer new therapeutic targets to develop important renoprotective treatments for DN over the next decade.
Shallow geological flows such as landslides, debris flows, and floods are frequently modeled mathematically in the depth-averaged framework. As the bed topography becomes steep and irregular, the ...classical shallow-water model loses accuracy. How to handle bed topography and gravity effects in depth-averaged models becomes important, and the validity of the model needs verifying. In this study, a differential transformation called the G2L transformation linking the global height to the local depth of the surface material is proposed. This transformation helps to reconstruct the landslide/avalanche surface for one-dimensional and two-dimensional terrains that are obviously curved as well as real landslide examples such as the Huangtian and Rongsong landslides with shallowness ratios as high as 1/4. With this G2L transformation and closures of the lateral and bed stress, two versions of a model governing the geological flow dynamics are developed to avoid difficulties in terrain treatment when using differential geometry. Version 1 of the model is a coupled hyperbolic–differential system; version 2 is a modified hyperbolic system. The two proposed models are verified by a simple one-dimensional granular flow problem on a steep slope. Both mitigate problems associated with computational differential geometry of geological flows and the singularity problem of shallow-water models. In particular, the reduced gravity of several current models in landslide dynamics is a special instance of version 2. The two proposed models are well able to mathematically model the gravity geological hazards and may provide the tools required for prediction and mitigation of natural geological hazards.
Lung diseases remain a serious problem for public health. The immune status of the body is considered to be the main influencing factor for the progression of lung diseases. HMGB1 (high‐mobility ...group box 1) emerges as an important molecule of the body immune network. Accumulating data have demonstrated that HMGB1 is crucially implicated in lung diseases and acts as independent biomarker and therapeutic target for related lung diseases. This review provides an overview of updated understanding of HMGB1 structure, release styles, receptors and function. Furthermore, we discuss the potential role of HMGB1 in a variety of lung diseases. Further exploration of molecular mechanisms underlying the function of HMGB1 in lung diseases will provide novel preventive and therapeutic strategies for lung diseases.
Structural colors are colors generated by the interaction between incident light and nanostructures. Structural colors have been studied for decades due to their promising advantages of long-term ...stability and environmentally friendly properties compared with conventional pigments and dyes. Previous studies have demonstrated many artificial structural colors inspired by naturally generated colors from plants and animals. Moreover, many strategies consisting of different principles have been reported to achieve dynamically tunable structural colors. Furthermore, the artificial structural colors can have multiple functions besides decoration, such as absorbing solar energy, anti-counterfeiting, and information encryption. In the present work, we reviewed the typical artificial structural colors generated by multilayer films, photonic crystals, and metasurfaces according to the type of structures, and discussed the approaches to achieve dynamically tunable structural colors.
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•Structural colors are colors generated by the interaction between incident light and nanostructures•High-resolution and long-term stable structural colors, can be designed as functional devices•Structural colors have application prospects in many fields, such as high-resolution printing and anti-counterfeiting
Laccases are encoded by a multigene family and widely distributed in plant genomes where they play roles oxidizing monolignols to produce higher-order lignin involved in plant development and stress ...responses. We identified 30 laccase genes (OsLACs) from rice, which can be divided into five subfamilies, mostly expressed during early development of the endosperm, growing roots, and stems. OsLACs can be induced by hormones, salt, drought, and heavy metals stresses. The expression level of OsLAC10 increased 1200-fold after treatment with 20 μM Cu for 12 h. The laccase activities of OsLAC10 were confirmed in an Escherichia coli expression system. Lignin accumulation increased in the roots of Arabidopsis over-expressing OsLAC10 (OsLAC10-OX) compared to wild-type controls. After growth on 1/2 Murashige and Skoog (MS) medium containing toxic levels of Cu for seven days, roots of the OsLAC10-OX lines were significantly longer than those of the wild type. Compared to control plants, the Cu concentration decreased significantly in roots of the OsLAC10-OX line under hydroponic conditions. These results provided insights into the evolutionary expansion and functional divergence of OsLAC family. In addition, OsLAC10 is likely involved in lignin biosynthesis, and reduces the uptake of Cu into roots required for Arabidopsis to develop tolerance to Cu.
Based on the engineering practices used in mining the protective coal seam at Huainan coalfield in China, this study investigates the temporal evolution of three-dimensional stress of the protected ...coal seam by numerical simulation. The coal body of the protected coal seam should first be loaded and then unloaded with the three-dimensional stress being reduced simultaneously. In accordance with the forcing process around the coal body of the protected coal seam, permeability experiments were performed under fixed axial displacement with unloading confining pressure (FADUCP) and fixed deviatone stress with unloading confining pressure (FDSUCP) stress paths. During the loading stage before the unloading point, the permeability and axial strain have a negative exponential relationship. However, during the unloading stage after the unloading point, the permeability and axial strain have a positive exponential relationship. Using the relationship between permeability and axial strain, along with the swelling and deformation of the protected coal seam, the permeability distribution characteristics for the protected coal seam was obtained. According to the permeability distribution characteristics of the protected coal seam, drilling designs for gas drainage can be optimized. Finally, the rationality of the drilling design was verified using gas data measured during mining of the protected coal seam.
Infiltration losses may be significant and warrant proper incorporation into mathematical models for river floods in arid and semi‐arid areas, rainfall‐induced surface runoffs in watersheds and ...swashes on beaches. Here, a depth‐averaged two‐dimensional hydrodynamic model is presented for such processes based on the cell‐centred finite volume method on unstructured meshes, with the full Green‐Ampt equation evaluating the infiltration rate. A local time stepping strategy is employed along with thread parallelization with Open Multi‐processing and high‐performance computing to reduce model run time and therefore facilitate applications for large‐scale processes. The numerical solutions generally agree with the experimental and field‐measured data for typical cases with significant infiltration losses. The case study shows that neglecting infiltration leads to an overestimated discharge hydrograph, which cannot be compensated by means of varied bed resistance as estimated by Manning roughness, and the infiltration parameters play disparate roles in modifying shallow flows compared with Manning roughness. In addition, infiltration affects bed shear stress, which in turn modifies the critical bed sediment size that could be initiated for incipient motion by the flow and therefore needs to be properly accounted for when sediment transport and morphological evolution are to be resolved.
An efficient model is proposed for shallow water flows featuring infiltration losses, with experimental and real cases reproduced satisfactorily. The neglect of infiltration leads to an overestimated discharge hydrograph and the infiltration parameters play disparate roles compared with Manning roughness. Infiltration loss may largely alter the threshold condition for sediment movement and thus warrants incorporation in the model.
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