Coronavirus disease 2019 (COVID‐19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) has led to an unprecedented setback for global economy and health. Vaccination is ...one of the most effective interventions to substantially reduce severe disease and death due to SARS‐CoV‐2 infection. Vaccination programmes are being rolled out globally, but most of these vaccines have been approved without extensive studies on their side‐effects and efficacy. Recently, new‐onset autoimmune phenomena after COVID‐19 vaccination have been reported increasingly (e.g. immune thrombotic thrombocytopenia, autoimmune liver diseases, Guillain–Barré syndrome, IgA nephropathy, rheumatoid arthritis and systemic lupus erythematosus). Molecular mimicry, the production of particular autoantibodies and the role of certain vaccine adjuvants seem to be substantial contributors to autoimmune phenomena. However, whether the association between COVID‐19 vaccine and autoimmune manifestations is coincidental or causal remains to be elucidated. Here, we summarize the emerging evidence about autoimmune manifestations occurring in response to certain COVID‐19 vaccines. Although information pertaining to the risk of autoimmune disease as a consequence of vaccination is controversial, we merely propose our current understanding of autoimmune manifestations associated with COVID‐19 vaccine. In fact, we do not aim to disavow the overwhelming benefits of mass COVID‐19 vaccination in preventing COVID‐19 morbidity and mortality. These reports could help guide clinical assessment and management of autoimmune manifestations after COVID‐19 vaccination.
As vaccination programmes are being rolled out globally, new‐onset autoimmune phenomena are emerging after COVID‐19 vaccination (e.g. immune thrombotic thrombocytopenia, autoimmune liver diseases, Guillain–Barré syndrome, IgA nephropathy, rheumatoid arthritis and systemic lupus erythematosus).
Rapid developments in the electric industry have promoted an increasing demand for lithium resources. Lithium in salt lake brines has emerged as the main source for industrial lithium extraction, ...owing to its low cost and extensive reserves. The effective separation of Mg
2+
and Li
+
is critical to achieving high recovery efficiency and purity of the final lithium product. This paper summarizes Mg
2+
/Li
+
separation materials and methods in the field of lithium recovery from salt lake brines. The review begins with an introduction to the global distribution and demand for lithium resources, followed by a description of the materials used in various separation techniques, including precipitation, adsorption, solvent extraction, nanofiltration membrane, electrodialysis, and electrochemical methods. A comparison, analysis, and outlook of such methods are comprehensively discussed in terms of principles, mechanisms, synthesis/operation, development, and industrial applications. We conclude with a presentation of challenges and insights into the future directions of lithium extraction from salt lake brines. A combination of the advantages of various materials is the most logical step toward developing novel methods for extracting lithium from brines with high separation selectivity, stability, low cost, and environmentally friendly characteristics.
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•Coordinative surface generation between geometry accuracy and microstructure characteristics is investigated in ultra-precision cutting tungsten-based alloy.•A nano-meter level ...roughness and continuous ultra-fine grained surface is obtained in ductile-mode removal process.•Dislocations accumulation induced by high-strain rate tool impact provides the primary driving forces for brittle-ductile transition and grain recrystallization.
High-precision and ultra-fine grained surface of tungsten heavy alloy exhibits superior service performance that is useful for many applications and shows promises for use as key parts in nuclear protection and precision instruments. The present study concentrated on a kind of precision-improving ultrasonic elliptic vibration cutting approaches, which fabricated nanometer-level surface roughness, inhibited subsurface damages evolution, and formed continuous ultra-fine grained layer microstructure. The surface morphologies have been characterized by ultra-depth three dimensional microscope and white light interferometer. Excellent machined surface quality was achieved under ultrasonic elliptic vibration cutting condition, and an ideal surface roughness of Sa = 70.7 nm was obtained. Microstructural alteration studied using EBSD technique and TEM observation confirmed the generation of ultra-fine grained structure. Surface grain size has been reduced from 50 ∼ 100 μm to 50 ∼ 300 nm without cracks and other micro-damages. Research demonstrated that surface energy accumulation and dislocations clustering induced by high-strain rate diamond tool impact provided the primary driving force of ductile-mode removal and grain recrystallization. A dislocation density-based simulation model was carried out to complement the static experimental investigations. The present work on surface formation and microstructural evolution identified that ultrasonic elliptical vibration machining has potential to deliver improved tungsten-based alloys service performance.
This paper first presents a generic model to characterize a variety of flexible demand-side resources (e.g., plug-in electric vehicles and distributed generation). Key sources of uncertainty ...affecting the modeling results are identified and are characterized via multiple stochastic scenarios. We then propose a risk-averse optimal bidding formulation for the resource aggregator at the demand side based on the conditional value-at-risk (VaR) theory. Specifically, this strategy seeks to minimize the expected regret value over a subset of worst-case scenarios whose collective probability is no more than a threshold value. Our approach ensures the robustness of the day-ahead (DA) bidding strategy while considering the uncertainties associated with the renewable generation, real-time price, and electricity demand. We carry out numerical simulations against three benchmark bidding strategies, including a VaR-based approach and a traditional scenario based stochastic programming approach. We find that the proposed strategy outperforms the benchmark strategies in terms of hedging high regret risks, and results in computational efficiency and DA bidding costs that are comparable to the benchmarks.
Plug-in electric vehicle (PEV) technology has drawn increasing amounts of attention in the last decade. As the world's largest automotive market, China has recently made the electrification of ...transportation central to its national strategic plan. Because of the unique nature of the vertically regulated power industry, China's massive deployment of PEVs has to face unique challenges that may not be encountered by any other country/region. Therefore, a comprehensive coordinated PEV charging scheme is urgently needed to facilitate the smooth grid integration of PEVs at all levels (e.g., transmission systems, distribution systems, and charging stations). This paper presents detailed mathematical modeling of a novel hierarchical framework for coordinated PEV charging at multiple timescales (i.e., day-ahead and real-time). The proposed three-level (e.g., provincial level, municipal level, and charging station level) PEV charging strategy jointly optimizes system load profile and charging costs while satisfying customer charging requirements. The interrelationships between various levels in terms of energy transaction and information exchange are clearly identified. Case studies on Guangdong Province, China, are carried out and simulation results demonstrate the effectiveness of our proposed hierarchical control framework in reducing system peak demand and charging costs.
Soil enzymes, as indicators of microbial metabolism, play an important role in nutrient biogeochemistry at the ecosystem level. In this study, we present information from a comprehensive analysis of ...the latitudinal variations in, and stoichiometric relationships between, soil β-glucosidase (BG), N-acetylglucosaminidase (NAG), leucine aminopeptidase (LAP), and acid phosphatase (AP) in nine forest ecosystems along the North-South Transect in eastern China. The results showed that soil BG and NAG activities were higher in temperate forests than in subtropical and tropical forests. Soil AP activities were the opposite, which indicates that microbial nutrient demand in tropical forests was limited by the nutrient phosphorus (P). Soil BG and NAG activities were significantly and negatively correlated with mean annual temperature (MAT), mean annual precipitation (MAP), the soil carbon (C):P and soil nitrogen (N):P ratios, but not with the soil C:N ratio. Soil NAG and AP activities were inversely correlated with soil pH, and soil AP activity increased as soil pH decreased. The latitudinal variations in the C:N, C:P, and N:P acquisition ratios represented by ln(BG):ln(LAP + NAG):ln(AP) activities across ecosystems were significantly and negatively related to MAP and MAT. The C:P and N:P acquisition ratios were positively related to soil pH but negatively related to the soil C:P and N:P ratios. The C:N and C:P acquisition ratios were also negatively correlated with leaf C:N, C:P, and N:P ratios. This study provides useful information about environmental controls on enzyme stoichiometry, and also highlights the stoichiometric and energy limitations on the metabolism of soil microbes.
•Soil BG and NAG activities increased as latitude increased.•Soil acid phosphatase was greatest in tropical and subtropical climate zones.•Latitudinal variation mechanism of soil EEA stoichiometry along the NSTEC.•Variations in the soil EEA stoichiometry were influenced by climate and soil pH.•Soil EEA stoichiometry was correlated with nutrients in plant leaves and soils.
Functionalized graphene oxide (f-GO) was synthesized by a simple covalent functionalization with 3-aminopropyltriethoxysilane (APTS). The hybrid polyvinylidene fluoride (PVDF) ultrafiltration ...membranes were then prepared by adding different ratios of graphene oxide (GO) and f-GO via phase inversion induced by immersion precipitation technique. Zeta potential demonstrated that covalent functionalization of GO with APTS was favorable for their homogeneous dispersion in organic solvents. SEM images showed that very large channel appeared in top-layer by the addition of additives. Furthermore, the PVDF/f-GO membranes exhibited superior hydrophilicity, water flux, BSA flux and rejection rate than nascent PVDF membranes and PVDF/GO membranes. Filtration results indicated that the fouling resistance parameters were significantly declined due to higher hydrophilicity of hybrid membranes. An atomic force microscope (AFM) analysis with a BSA-immobilized tip revealed that the adhesion forces between membrane and foulants increased in the following order: PVDF/f-GO<PVDF/GO<PVDF. After a ternary cycle BSA solution inner fouling process, PVDF/f-GO membranes exhibited higher water flux recovery ratio (FRR) value than that of PVDF/GO. Meanwhile, tensile strength and elongation-at-break of PVDF/f-GO membranes were increased by 69.01% and 48.38% compared with those of PVDF/GO membranes, which is believed to be attributed to the strong interfacial interaction between f-GO and matrix by covalent functionalization of GO. As a result, GO functionalization will provide a promising method to fabricate graphene-based hybrid membranes with effective reinforced permeation, antifouling and mechanical performance.
Due to reduced agglomeration of graphene oxide and enhanced interaction between additives and polymer matrix, the performances of organosilane-functionalized graphene oxide-based ultrafiltration membranes outweigh others. Display omitted
•Effect of organosilane-functionalized graphene oxide was remarkable.•Foulants tended to be deposited on the rough surface.•Permeability and antifouling performance were increased significantly.•Tensile strength was improved obviously.
High mobility group box 1 protein (HMGB1), originally characterized as a nuclear DNA-binding protein, has also been described to have an extracellular role when it is involved in cellular activation ...and proinflammatory responses. In this study, FLAG-tagged HMGB1 was inducibly expressed in the presence of culture media with or without added IL-1beta, IFN-gamma, or TNF-alpha. HMGB1 purified from cells grown in culture media alone only minimally increased cytokine production by MH-S macrophages and had no effect on murine neutrophils. In contrast, HMGB1 isolated from cells cultured in the presence of IL-1beta, IFN-gamma, and TNF-alpha had enhanced proinflammatory activity, resulting in increased production of MIP-2 and TNF-alpha by exposed cells. IL-1beta was bound to HMGB1 isolated from cells cultured with this cytokine, and purified HMGB1 incubated with recombinant IL-1beta acquired proinflammatory activity. Addition of anti-IL-1beta Abs or the IL-1 receptor antagonist to cell cultures blocked the proinflammatory activity of HMGB1 purified from IL-1beta-exposed cells, indicating that such activity was dependent on interaction with the IL-1 receptor. These results demonstrate that HMGB1 acquires proinflammatory activity through binding to proinflammatory mediators, such as IL-1beta.
ABSTRACT
N‐Glycans are involved in numerous biologic processes, such as cell adhesion, migration, and invasion. To distinguish the functions of complex high‐mannose types of N‐glycans, we used the ...clustered, regularly interspaced, short palindromic repeats/Cas9 system to establish N‐acetylglucosaminyltransferase (GnT)‐I‐knockout (KO) cells. Loss of GnT‐I greatly induced cell‐cell adhesion and decreased cell migration. In addition, the expression levels of epithelial‐mesenchymal transition (EMT) markers such as α‐SMA, vimentin, and N‐cadherin were suppressed, whereas the expression of claudin‐1 was promoted, suggesting a mesenchymal‐epithelial transition‐like phenotype, an opposite process to the EMT, was occurred in the KO cells. The phosphorylation levels of Smad‐2, epidermal growth factor receptor, and integrin‐mediated focal adhesion kinase (FAK) were consistently suppressed. Furthermore, the restoration of GnT‐I in the KO cells suppressed the cell‐cell adhesion and augmented the expression of EMT markers as well as that of FAK activation. The expression levels of integrins were upregulated in the KO cells, although their functions were decreased, whereas their expression levels were downregulated in the rescued cells, which suggests a negative feedback loop between function and expression. Finally, we also found that the expression of GnT‐I was important for cell survival, resistance to cancer drugs, and increased colony formation. The results of the present study demonstrate that GnT‐I works as a switch to turn on/off EMT, which further supports the notion that on most surface receptors, the N‐glycans differentially play essential roles in biologic functions.—Zhang, G., Isaji, T., Xu, Z., Lu, X., Fukuda, T., Gu, J. N‐acetylglucosaminyltransferase‐I as a novel regulator of epithelial‐mesenchymal transition. FASEB J. 33, 2823–2835 (2019). www.fasebj.org
The provenance of Taklamakan desert sand Rittner, Martin; Vermeesch, Pieter; Carter, Andrew ...
Earth and planetary science letters,
03/2016, Volume:
437
Journal Article
Peer reviewed
Open access
•The first comprehensive multi-proxy provenance analysis of the Tarim Basin.•Taklamakan sand is derived from the Kunlun Shan, Altun Shan, and Pamir regions.•Little sediment from the Tian Shan reaches ...the sand desert.•Wind and water work in opposite directions, balancing sand supply and topography.•Tarim Basin is no significant source to the Chinese Loess, nor is the Junggar Basin.
Sand migration in the vast Taklamakan desert within the Tarim Basin (Xinjiang Uyghur Autonomous region, PR China) is governed by two competing transport agents: wind and water, which work in diametrically opposed directions. Net aeolian transport is from northeast to south, while fluvial transport occurs from the south to the north and then west to east at the northern rim, due to a gradual northward slope of the underlying topography. We here present the first comprehensive provenance study of Taklamakan desert sand with the aim to characterise the interplay of these two transport mechanisms and their roles in the formation of the sand sea, and to consider the potential of the Tarim Basin as a contributing source to the Chinese Loess Plateau (CLP). Our dataset comprises 39 aeolian and fluvial samples, which were characterised by detrital-zircon U–Pb geochronology, heavy-mineral, and bulk-petrography analyses. Although the inter-sample differences of all three datasets are subtle, a multivariate statistical analysis using multidimensional scaling (MDS) clearly shows that Tarim desert sand is most similar in composition to rivers draining the Kunlun Shan (south) and the Pamirs (west), and is distinctly different from sediment sources in the Tian Shan (north). A small set of samples from the Junggar Basin (north of the Tian Shan) yields different detrital compositions and age spectra than anywhere in the Tarim Basin, indicating that aeolian sediment exchange between the two basins is minimal. Although river transport dominates delivery of sand into the Tarim Basin, wind remobilises and reworks the sediment in the central sand sea. Characteristic signatures of main rivers can be traced from entrance into the basin to the terminus of the Tarim River, and those crossing the desert from the south to north can seasonally bypass sediment through the sand sea. Smaller ephemeral rivers from the Kunlun Shan end in the desert and discharge their sediment there. Both river run-off and wind intensity are strongly seasonal, their respective transport strength and opposing directions maintain the Taklamakan in its position and topography.
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