The variations and dynamics of essential and toxic metal(loid)s in patients with COVID‐19 may associate with the progression and fatal outcome of the disease, which still remains to investigate. In ...the present study, a retrospective analysis was performed in a cohort of 306 confirmed COVID‐19 patients admitted to Tongji hospital (Wuhan, China) from February 10 to March 15, 2020. Whole blood levels of essential and/or toxic metal(loid)s were analyzed, including magnesium, calcium, chromium, manganese, iron, copper, zinc, arsenic, cadmium, mercury, thallium, and lead according to the disease severity and outcome. Compared to the non‐severe COVID‐19 patients, severe cases showed significant higher levels of whole blood calcium, chromium, and copper, but lower levels of magnesium, manganese, iron, zinc, arsenic, thallium, and lead. These differences were further found consistently across the clinical course since the disease onset by longitudinal analysis. Among the severe patients, chromium and cadmium were higher in the deceased group compared to the recovered group, while arsenic was lower. Whole blood iron, age, and sex were determined to be independent factors associated with the disease severity, while chromium, cadmium, and the comorbidity of cardiovascular disease were determined to be independent factors associated with the mortality. These results suggest that variations of whole blood metal(loid)s may be associated with the severe illness and fatal outcome of COVID‐19, which could be persistently monitored and would be helpful in the evaluation of the dynamic changes in patients with COVID‐19.
A reconfigurable actuator is a stimuli-responsive structure that can be programmed to adapt different shapes under identical stimulus. Reconfigurable actuators that function without control circuitry ...and are fueled remotely are in great demand to devise adaptive soft robotic devices. Yet, obtaining fast and reliable reconfiguration remains a grand challenge. Here we report a facile fabrication pathway towards reconfigurability, through synergistic use of photochemical and photothermal responses in light-active liquid crystal polymer networks. We utilize azobenzene photoisomerization to locally control the cis-isomer content and to program the actuator response, while subsequent photothermal stimulus actuates the structure, leading to shape morphing. We demonstrate six different shapes reconfigured from one single actuator under identical illumination conditions, and a light-fueled smart gripper that can be commanded to either grip and release or grip and hold an object after ceasing the illumination. We anticipate this work to enable all-optical control over actuator performance, paving way towards reprogrammable soft micro-robotics.
Due to their environmental sustainability and high efficiency, proton‐exchange‐membrane fuel cells (PEMFCs) are expected to be an essential type of energy source for electric vehicles, energy ...generation, and the space industry in the coming decades. Here, the recent developments regarding shape‐controlled nanostructure catalysts are reviewed, with a focus on the stability of high‐performance Pt‐based catalysts and related mechanisms. The catalysts, which possess great activity, are still far from meeting the requirements of their applications, due to stability issues, especially in membrane electrode assemblies (MEAs). Thus, solutions toward the comprehensive performance of Pt‐based catalysts are discussed here. The research trends and related theories that can promote the application of Pt‐based catalysts are also provided.
Recent developments regarding high‐performance nanostructured catalysts, especially in durability, are summarized. Their durability severely limits the application of shape‐controlled catalysts. Thus, the solutions to improve their durability are systematically introduced and their feasibility is also analyzed, with reference to the design of a new generation of Pt‐based catalysts.
Soil stabilization technology based on microbial-induced carbonate precipitation (MICP) has gained widespread interest in geotechnical engineering. MICP has been found to be able to improve soil ...strength, stiffness, liquefaction resistance, erosion resistance, while maintaining a good permeability simultaneously. MICP processes involves a series of biochemical reactions that are affected by many factors, both intrinsically and externally. This paper reviews various influential factors for MICP process, including bacterial species, concentration of bacteria, temperature, pH, composition and concentration of cementation solution, grouting strategies, and soil properties. Through this comprehensive review, we find that: (1) the species and strains of bacteria, concentration of bacteria solution, temperature, pH value, and the cementation solution properties all affect the characteristics of formed calcium carbonate, such as crystal type, appearance and size, which consequently affect the cementation degree and distribution in geomaterials; (2) the condition with temperature between 20 and 40 °C, pH between 7 and 9.5, the concentration of the cementation solution within 1 mol/L, and high bacteria concentration is optimal for applying MICP in soil. Under the optimal condition, relatively low temperature, high pH value, and low concentration of cementation solution could help retain permeability and vice versa; (3) the effective grain size ranging from 10 to 1000 µm. MICP treatment works most effectively for larger size, well-graded sand; (4) the multi-phase, multi-concentration or electroosmotic grouting method can improve the MICP treatment efficiency. The grouting velocity below 0.042 mol/L/h is beneficial for improving the utilization ratio of cementation solution. The recommended grouting pressure is generally between 0.1 and 0.3 bar for MICP applications in sand and should not exceed 1.1 bar for silty and clayey soils.
We study the genuine tripartite nonlocality (GTN) and the genuine tripartite entanglement (GTE) of Dirac fields in the background of a Schwarzschild black hole. We find that the Hawking radiation ...degrades both the physically accessible GTN and the physically accessible GTE. The former suffers from “sudden death” at some critical Hawking temperature, and the latter approaches to the nonzero asymptotic value in the limit of infinite Hawking temperature. We also find that the Hawking effect cannot generate the physically inaccessible GTN, but can generate the physically inaccessible GTE for fermion fields in curved spacetime. These results show that on the one hand the GTN cannot pass through the event horizon of black hole, but the GTE do can, and on the other hand the surviving physically accessible GTE and the generated physically inaccessible GTE for fermions in curved spacetime are all not nonlocal. Some monogamy relations between the physically accessible GTE and the physically inaccessible GTE are found.
Up to 10–20% of patients with coronavirus disease 2019 (COVID‐19) develop a severe pulmonary disease due to immune dysfunction and cytokine dysregulation. However, the extracellular proteomic ...characteristics in respiratory tract of these critical COVID‐19 patients still remain to be investigated. In the present study, we performed a quantitative proteomic analysis of the bronchoalveolar lavage fluid (BALF) from patients with critical COVID‐19 and from non‐COVID‐19 controls. Our study identified 358 differentially expressed BALF proteins (P < 0.05), among which 41 were significantly changed after using the Benjamini–Hochberg correction (q < 0.05). The up‐regulated signaling was found to be mainly involved in inflammatory signaling and response to oxidative stress. A series of increased extracellular factors including Tenascin‐C (TNC), Mucin‐1 (KL‐6 or MUC1), Lipocalin‐2 (LCN2), periostin (POSTN), Chitinase 3‐like 1 (CHI3L1 or YKL40), and S100A12, and the antigens including lymphocyte antigen 6D/E48 antigen (LY6D), CD9 antigen, CD177 antigen, and prostate stem cell antigen (PSCA) were identified, among which the proinflammatory factors TNC and KL‐6 were further validated in serum of another thirty‐nine COVID‐19 patients and healthy controls, showing high potentials of being biomarkers or therapeutic candidates for COVID‐19. This BALF proteome associated with COVID‐19 would also be a valuable resource for researches on anti‐inflammatory medication and understanding the molecular mechanisms of host response.
Database
Proteomic raw data are available in ProteomeXchange (http://proteomecentral.proteomexchange.org) under the accession number PXD022085, and in iProX (www.iprox.org) under the accession number IPX0002429000.
Here, we use quantitative proteomics to analyze alterations in the bronchoalveolar lavage fluid of patients with critical COVID‐19 relative to non‐COVID‐19 controls. We find that up‐regulated signaling mainly involves inflammatory signaling and response to oxidative stress and identify increases in extracellular factors and in their related interaction networks. The bronchoalveolar proteome of COVID‐19 patients provides a valuable resource for future research.
The purpose of this paper is to review the development and the state of the art in desiccation cracking characterization methods and review the desiccation cracking behaviors of soils. The review ...begins by briefly introducing in Section 1 the influences of desiccation cracking on soil properties and the significance of studying this topic. Section 2 summarizes the past and existing experimental approaches that have been invented and adopted for soil desiccation cracking investigations at both laboratory and field scales. Various theoretical frameworks formulated to account for the underlying cracking mechanisms are presented in Section 3. Section 4 shows the implementation of theoretical frameworks into mesh-based and mesh-free numerical tools to capture the initiation, propagation, and coalescence of desiccation cracks. Section 5 describes the crack dynamics in desiccating soils, with emphases placed on the coupled process of water evaporation, suction increase, and volume shrinkage, and the crack network evolution. Section 6 discusses major influencing factors of soil desiccation cracking covering soil intrinsic properties, boundary constraints, environmental conditions, and soil admixtures. Finally, a brief summary and proposed prospective research works are presented in Sections 7.
An unprecedented reaction for the direct trifluoromethylthiolation and fluorination of alkyl alcohols using AgSCF3 and nBu4NI has been developed. The trifluoromethylthiolated compounds and alkyl ...fluorides were selectively formed by changing the ratio of AgSCF3/nBu4NI. This protocol is tolerant of different functional groups and might be applicable to late‐stage trifluoromethylthiolation of alcohols.
Silver bullet: A new strategy has been developed for the direct trifluoromethylthiolation of alkyl alcohols using AgSCF3 and nBu4NI. This protocol does not require the activation of alcohols in advance. A variety of alkyl alcohols bearing different functional groups were transformed into the corresponding alkyl trifluoromethyl sulfides in moderate to good yields.
Abstract
Lifting the valley degeneracy of monolayer transition metal dichalcogenides (TMDs) would allow versatile control of the valley degree of freedom. We report a giant valley exciton splitting ...of 16 meV/T for monolayer WS
2
, using the proximity effect from an EuS substrate, which is enhanced by nearly two orders of magnitude from that obtained by an external magnetic field. More interestingly, a sign reversal of the valley splitting is observed as compared to that of WSe
2
on EuS. Using first principles calculations, we investigate the complex behavior of exchange interactions between TMDs and EuS. The sign reversal is attributed to competing ferromagnetic (FM) and antiferromagnetic (AFM) exchange interactions for Eu- and S- terminated EuS surface sites. They act differently on the conduction and valence bands of WS
2
compared to WSe
2
. Tuning the sign and magnitude of the valley exciton splitting offers opportunities for control of valley pseudospin for quantum information processing.
Aryl trifluoromethyl ethers (ArOCF3) are prevalent in pharmaceuticals, agrochemicals, and materials. However, methods for the general and efficient synthesis of these compounds are extremely ...underdeveloped and limited. Herein, we describe a highly efficient and general procedure for the direct O‐trifluoromethylation of unprotected phenols through a silver‐mediated cross‐coupling reaction using CF3SiMe3 as the CF3 source and exogenous oxidants. This novel oxidative trifluoromethylation provides access to a wide range of aryl trifluoromethyl ethers from simple phenols. The mild process was also applied to the late‐stage trifluoromethylation of a medicinally relevant compound.
Combining two nucleophiles: The direct oxidative O‐trifluoromethylation of phenols with CF3SiMe3 provides a general and practical method for the preparation of aryl trifluoromethyl ethers. A wide variety of functional groups are tolerated under these conditions, and the method can also be employed for the late‐stage trifluoromethylation of complex pharmaceutically relevant molecules (NFSI= N‐fluorobenzenesulfonimide).
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