Electronic tattoos (E‐tattoos), which can be intimately mounted on human skin for noninvasive and high‐fidelity sensing, have attracted the attention of researchers in the field of wearable ...electronics. However, fabricating E‐tattoos that are capable of self‐healing and sensing multistimuli, similar to the inherent attributes of human skin, is still challenging. Herein, a healable and multifunctional E‐tattoo based on a graphene/silk fibroin/Ca2+ (Gr/SF/Ca2+) combination is reported. The highly flexible E‐tattoos are prepared through printing or writing using Gr/SF/Ca2+ suspension. The graphene flakes distributed in the matrix form an electrically conductive path that is responsive to environmental changes, such as strain, humidity, and temperature variations, endowing the E‐tattoo with high sensitivity to multistimuli. The performance of the E‐tattoo is investigated as a strain, humidity, and temperature sensor that shows high sensitivity, a fast response, and long‐term stability. The E‐tattoo is remarkably healed after damage by water because of the reformation of hydrogen and coordination bonds at the fractured interface. The healing efficiency is 100% in only 0.3 s. Finally, as proof of concept, its applications for monitoring of electrocardiograms, breathing, and temperature are shown. Based on its unique properties and superior performance, the Gr/SF/Ca2+ E‐tattoo may be a promising candidate material for epidermal electronics.
A self‐healable silk E‐tattoo, which shows high sensitivity to multistimuli including strain/humidity/temperature, is reported. Customer‐designed E‐tattoos can be facilely prepared through screen printing or direct writing of a graphene/silk fibroin/Ca2+ suspension. Remarkably, the E‐tattoo can be healed with an efficiency of 100% even after being fully fractured within 0.3 s simply by a droplet of water.
The central nervous system is particularly susceptible to DNA repair deficiency, which renders a variety of neurodevelopmental and neurodegenerative disorders in humans. It is generally believed that ...DNA damage occurs upon repetitive replication and oxidative stress in highly proliferating neuroprogenitor cells (NPs), or due to high rates of metabolism and active neuronal activity in terminally differentiated neurons. DNA double‐stranded breaks (DSBs) and single‐stranded breaks (SSBs) constitute the most prevalent forms of DNA damage, which can result in neuronal apoptosis if unrepaired. Despite these notions, there are still gaps in our knowledge regarding the mechanism and specificity of DNA damage and repair in the neural development and the homeostasis of neural tissues. Recent studies have identified recurrent DSBs within neuronal long genes in NPs and ‘programmed’ SSBs in neuronal activity genes. However, the physiological function of these DNA breakages in the nervous system has not been so far explored. In this review, we summarise the recent advances in the field of DNA damage and DNA repair in neural development and neuropathies.
Programmed DNA breaks occur in neural progenitors during gene rearrangement. In neuronal cells, intrinsic and extrinsic signals can induce DNA breaks in promoters of response genes. Under DNA repair deficient conditions, these DNA damages accumulate and represent an etiological factor for human neurodevelopmental and neurodegenerative pathologies. Here, we summarise recent research on ‘programmed’ DNA breaks and their repair in these neural cells and imply their physiological functions in the nervous system.
The distortion in machining aeronautical aluminum alloy parts (AAAPs) is one of the serious challenges in the aviation industry, and the residual stresses produced in multimanufacturing steps are the ...main cause. In order to get a comprehensive understanding of the problems about residual stresses and distortion in machining AAAPs, the state-of-the-art in several aspects including the generation reasons of residual stresses, the factors influencing distortion during machining, the measurement methods of residual stresses, the prediction and controlling methods of distortion are summarized in this paper. The generation mechanism of the bulk residual stress inner materials and the machining-induced residual stresses, as well as the factors affecting two kinds of residual stresses are stated. Also, the influences of residual stresses and machining process conditions on distortion are analyzed. Furthermore, the common residual stress measurement methods and its application scope are summarized. Significantly, the differences, advantages, and disadvantages of various prediction methods are analyzed. The methods of controlling distortion before and after machining are summarized. Finally, the paper gives out further research on the distortion in machining AAAPs in aeronautical manufacturing.
Inspired by the unique structure and function of the natural chloride channel (ClC) selectivity filter, we present herein the design of a ClC‐type single channel molecule. This channel displays high ...ion transport activity with half‐maximal effective concentration, EC50, of 0.10 μM, or 0.075 mol % (channel molecule to lipid ratio), as determined by fluorescent analysis using lucigenin‐encapsulated vesicles. Planar bilayer lipid membrane conductance measurements indicated an excellent Cl−/K+ selectivity with a permeability ratio P
Cl-
${{_{{\rm Cl}{^{- }}}$
/P
K+
${{_{{\rm K}{^{+}}}$
up to 12.31, which is comparable with the chloride selectivity of natural ClC proteins. Moreover, high anion/anion selectivity (P
Cl-
${{_{{\rm Cl}{^{- }}}$
/P
Br-
${{_{{\rm Br}{^{- }}}$
=66.21) and pH‐dependent conductance and ion selectivity of the channel molecule were revealed. The ClC‐like transport behavior is contributed by the cooperation of hydrogen bonding and anion–π interactions in the central macrocyclic skeleton, and by the existence of pH‐responsive terminal phenylalanine residues.
An artificial anion channel with chloride selectivity comparable to that of natural chloride channel (ClC) proteins was achieved by rational engineering of the central active region of an hourglass‐shaped single‐molecule structure. By incorporating terminal pH‐sensitive groups, our artificial anion channel also mimicked the pH‐responsive feature of natural ClC proteins.
With the increasing demand for high-quality skilled talents, building a teaching management system suitable for the characteristics of modern apprenticeship is the key to ensuring the smooth ...implementation of practical teaching. After the contemporary apprenticeship quality management system, this article takes vocational college students under the current apprenticeship management system in S city as the research object, uses principal component analysis and multiple choice linear regression methods to evaluate student initiative and explore the relevant influencing factors, Assess the impact and degree of influence of various factors on the agency of vocational college students. The results show that motivation investment (0.2421) and emotional investment (0.2335) are closely related to the evaluation results of student agency. The agency of the selected students is at a lower than average level, with an evaluation score of 2.9096. The impact value of the modern apprenticeship management system on student agency is 3.561, above average. Among them, The impact of factor process (3.838) is the greatest
Since its discovery two decades ago, anion‐π interaction has been increasingly recognized as an important driving force. Extensive theoretical and experimental efforts on the ground‐state anion‐π ...binding and recognition have laid the bases for exploring its relevance in catalysis. Accordingly, the concept of “anion‐π catalysis” that employing an electron‐deficient π surface (π‐acidic surface) for anionic reaction intermediate and transition state stabilization has emerged. This article shortly reviews the emergence and development of this concept, aiming to provide an emphasis on the general concept and key progress in this exciting area. To highlight the essential contribution of anion‐π interactions, the contents are organized according to their role engaged in catalytic process, for example from both ground‐state and transition‐state stabilization to solely transition‐state stabilization, mainly by a single π‐face, and to cooperative π‐face activation. A concluding remark and outlook on future development of this field is also given.
The emergence and development of the concept of “anion‐π catalysis”, that employing an electron‐deficient π surface for anionic intermediate and transition state stabilization, is illustrated. Different activation modes are presented to highlight the essential contribution of anion‐π interactions, from both ground‐state and transition‐state stabilization to solely transition‐state stabilization, and to cooperative π‐face activation.
Frozen dough technology could effectively extend the shelf life of bread to ensure the freshness, which is widely used and gradually replace the traditional bread production. However, during the ...production and storage of frozen dough, a series of problems could take place, such as inhibition of yeast activity, damage of the structure of the dough, leading to the deterioration of dough quality.
This review summarizes the factors that affect the final quality of frozen dough, including yeast activity, dough structure and dough properties. Some effective methods for improving freeze tolerance of yeast, dough structure and dough properties are discussed, including addition of various additives, use of genetic engineering technique, optimization of freezing and storage conditions, and employment of novel freezing technology.
The addition of additives can not only improve the freeze tolerance of yeast but also maintain the rheological and thermophysical properties of dough. Through the modification of gene, freeze tolerance and fermentation ability of yeast can be improved. Optimizing freezing and storage conditions ensures the activity of yeast as well as dough network structure so that freezing damage due to ice crystals can be minimized. In addition, novel freezing technology such as ultrasound-assisted freezing can simultaneously accelerate the freezing process as well as generate fine and uniform ice crystals, thus protecting dough network structure.
•Effective methods for enhancing frozen dough quality are reviewed.•Additives improve freeze tolerance of yeast and maintain dough property.•Gene modification enhances freeze tolerance and fermentation ability of yeast.•Optimizing freezing and storage conditions ensures the activity of yeast.•Novel freezing technology protects dough network structure.
Circ‐Foxo3 is a circRNA encoded by the human FOXO3 gene and works as a sponge for potential microRNAs (miRNAs) to regulate cancer progression. However, the role of circ‐Foxo3 in esophageal squamous ...cell cancer (ESCC) is not clear. In this study, circ‐Foxo3 was lowly expressed in cell lines and ESCC tissues. Meanwhile, overexpression of circ‐Foxo3 inhibited cell growth, migration, and invasion, whether in vivo or in vitro. Mechanically, we found a potential miRNA target, miR‐23a, which negatively correlated with circ‐Foxo3 in ESCC. Then, a luciferase assay confirmed the relationship between the circ‐Foxo3 and miRNA. Moreover, circ‐Foxo3 upregulation of PTEN occurred through “sponging” miR‐23a. Taken together, these results indicated that the circ‐Foxo3/miR‐23a/PTEN pathway was critical for inhibiting the ESCC progression. This may provide a promising target for treat ESCC.
The circ‐Foxo3/miR‐23a/PTEN pathway is possibly a critical factor in inhibiting esophageal squamous cell cancer (ESCC) progression. This may provide a promising target for treating ESCC.
Atropisomeric biaryl motifs are ubiquitous in chiral catalysts and ligands. Numerous efficient strategies have been developed for the synthesis of axially chiral biaryls. In contrast, the asymmetric ...construction of o-quinone-aryl atropisomers has yet to be realized. Inspired by the rapid progress of the chemistry of biaryls, here we present our initial investigations about the atroposelective construction of axially chiral arylquinones by a bifunctional chiral phosphoric acid-catalyzed asymmetric conjugate addition and central-to-axial chirality conversion. With o-naphthoquinone as both the electrophile and the oxidant, three types of arylation counterparts, namely 2-naphthylamines, 2-naphthols and indoles, are utilized to assemble a series of atropisomeric scaffolds in good yields and excellent enantioselectivities. This approach not only expands the axially chiral library but also offers a route to a class of potential, chiral biomimetic catalysts.
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