Fabrication of soft piezoelectric nanomaterials is essential for the development of wearable and implantable biomedical devices. However, a big challenge in this soft functional material development ...is to achieve a high piezoelectric property with long‐term stability in a biological environment. Here, a one‐step strategy for fabricating core/shell poly(vinylidene difluoride) (PVDF)/dopamine (DA) nanofibers (NFs) with a very high β‐phase content and self‐aligned polarization is reported. The self‐assembled core/shell structure is believed essential for the formation and alignment of β‐phase PVDF, where strong intermolecular interaction between the NH2 groups on DA and the CF2 groups on PVDF is responsible for aligning the PVDF chains and promoting β‐phase nucleation. The as‐received PVDF/DA NFs exhibit significantly enhanced piezoelectric performance and excellent stability and biocompatibility. An all‐fiber‐based soft sensor is fabricated and tested on human skin and in vivo in mice. The devices show a high sensitivity and accuracy for detecting weak physiological mechanical stimulation from diaphragm motions and blood pulsation. This sensing capability offers great diagnostic potential for the early assessment and prevention of cardiovascular diseases and respiratory disorders.
High‐performance poly(vinylidene difluoride)/dopamine core/shell piezoelectric nanofibers with excellent stability are successfully fabricated by one‐step electrospinning in large scale and quantity, offering an extraordinary building block for developing self‐powered sensor devices to detect weak absolute pressure change from soft tissues in vivo. This sensing capability offers great diagnostic potential for the early assessment and prevention of cardiovascular diseases and respiratory disorders.
Covalent organic frameworks (COF) are complex functional systems constructed with atomic precision by linking well‐defined building blocks through robust covalent bonds. β‐cyclodextrin (β‐CD) is a ...most employed supramolecule which bears a hydrophobic cavity guiding molecular specific recognitions. Building COF with asymmetric β‐CD linkers is challenging and has never been reported. Here, β‐CD COF is grown with heptakis(6‐amino‐6‐deoxy)‐β‐CD and terephthalaldehyde in green solvents of water and ethanol at room temperature. The COF is characterized by powder X‐ray diffraction, which matches well with the simulated crystal structure. Weaving β‐CD into a framework through reticular chemistry allows the integration of a large amount of β‐CD units (50 mol %), much higher than β‐CD polymers. The β‐CD COF has larger surface area, more uniform pore size, and higher thermal stability than the non‐crystalline β‐CD polymer produced by the same reagents. Finally, the β‐CD COF holds abundant specific interaction sites enabling selective molecular adsorption.
Porous β‐cyclodextrin (CD) cubic poles: The first success of using an asymmetric supramolecular building block, β‐CD, for the construction of a covalent organic framework. The framework is built from heptakis(6‐amino‐6‐deoxy)‐β‐CD and terephthalaldehyde under acid catalysis in aqueous ethanol at room temperature. It exhibits a morphology of cubic poles, with an average width of 125 nm. The material has a high surface area, uniform pore size, and abundant β‐CD units, enabling highly selective molecular adsorption in water.
The imbalance of immune status in cancer microenvironment plays an important role in the development and progression of cancer. Immunotherapy based on this has become an important field of cancer ...research in recent years. Many studies on long noncoding RNA (lncRNA) in cancer have focus on its regulation in cancer development and metastasis. Recent studies have suggested that lncRNAs play crucial roles in different phases of cancer immunity, including antigen releasing, antigen presentation, immune activation, immune cells migration, infiltrating into cancer tissues, and killing cancer cells. The functional studies of lncRNAs in cancer immuntity revealed the complicated molecular mechanisms in cancer immunity from a new point of view, which may provide novel potential targets for cancer immunotherapies. Based on the classical cancer‐immunity cycle theory, we review the recent studies on the functions and mechanisms of immune‐related lncRNAs in different stages of cancer immunity, to summarize the relationship between lncRNAs, and cancer immunity and to provide a framework for further research.
The functional studies of lncRNAs in cancer immuntity revealed the complicated molecular mechanisms in cancer immunity from a new point of view, which may provide novel potential targets for cancer immunotherapies. Based on the classical cancer‐immunity cycle theory, we review therecent studies on the functions and mechanisms of immune‐related lncRNAs in different stages of cancer immunity, to summarize the relationship between lncRNAs, and cancer immunity and to provide a framework for further research.
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bstract
In the geometric approach to defining complexity, operator complexity is defined as the distance in the operator space. In this paper, based on the analogy with the circuit complexity, the ...operator size is adopted as the metric of the operator space where the path length is the complexity. The typical sectional curvatures of this complexity geometry are positive. It is further proved that the typical sectional curvatures are always positive if the metric is an arbitrary function of operator size, while complexity geometry is usually expected to be defined on negatively curved manifolds. By analyzing the sectional curvatures distribution for the
N
-qubit system, it is shown that surfaces generated by Hamiltonians of size smaller than the typical size can have negative curvatures. In the large
N
limit, the form of complexity metric is uniquely constrained up to constant corrections if we require sectional curvatures are of order 1
/N
2
. With the knowledge of states, the operator size should be modified due to the redundant action of operators, and thus is generalized to be state-dependent. Then we use this state-dependent operator size as the metric of the Hilbert space to define state complexity. It can also be shown that in the Hilbert space, 2-surfaces generated by operators of size much smaller than the typical size acting on typical states also have negative curvatures.
The long‐segment peripheral nerve injury (PNI) represents a global medical challenge, leading to incomplete nerve tissue recovery and unsatisfactory functional reconstruction. However, the current ...electrical stimulation (ES) apparatuses fail perfect nerve repair due to their inability of the variable synchronous self‐regulated function with physiological states. It is urgent to develop an implantable ES platform with physiologically adaptive function to provide instantaneous and nerve‐preferred ES. Here, a physiologically self‐regulated electrical signal is generated by integrating a novel tribo/piezoelectric hybrid nanogenerator with a nanoporous nerve guide conduit to construct a fully implantable neural electrical stimulation (FI‐NES) system. The optimal neural ES parameters completely originate from the body itself and are highly self‐responsive to different physiological states. The morphological evaluation, representative protein expression level, and functional reconstruction of the regenerated nerves are conducted to assess the PNI recovery process. Evidence shows that the recovery effect of 15 mm length nerve defects under the guidance of the FI‐NES system is significantly close to the autograft. The designed FI‐NES system provides an effective method for long‐term accelerating the recovery of PNI in vivo and is also appropriate for other tissue injury or neurodegenerative diseases.
A physiologically self‐regulated, fully implantable, battery‐free neural electrical stimulation system is successfully constructed to produce physiologically electrical signals for the acceleration of regeneration and functional recovery of peripheral nerve injury.
Glucose is the major precursor of lactose, which is synthesized in Golgi vesicles of mammary secretory alveolar epithelial cells during lactation. Glucose is taken up by mammary epithelial cells ...through a passive, facilitative process, which is driven by the downward glucose concentration gradient across the plasma membrane. This process is mediated by facilitative glucose transporters (GLUTs), of which there are 14 known isoforms. Mammary glands mainly express GLUT1 and GLUT8, and GLUT1 is the predominant isoform with a
K
m
of ~10 mM and transport activity for mannose and galactose in addition to glucose. Mammary glucose transport activity increases dramatically from the virgin state to the lactation state, with a concomitant increase in GLUT expression. The increased GLUT expression during lactogenesis is not stimulated by the accepted lactogenic hormones. New evidence indicates that a possible low oxygen tension resulting from increased metabolic rate and oxygen consumption may play a major role in stimulating glucose uptake and GLUT1 expression in mammary epithelial cells during lactogenesis. In addition to its primary presence on the plasma membrane, GLUT1 is also expressed on the Golgi membrane of mammary epithelial cells and is likely involved in facilitating the uptake of glucose and galactose to the site of lactose synthesis. Because lactose synthesis dictates milk volume, regulation of GLUT expression and trafficking represents potentially fruitful areas for further research in dairy production. In addition, this research will have pathological implications for the treatment of breast cancer because glucose uptake and GLUT expression are up-regulated in breast cancer cells to accommodate the increased glucose need.
A polymer fibril assembly can dictate the morphology framework, in forming a network structure, which is highly advantageous in bulk heterojunction (BHJ) organic solar cells (OSCs). A fundamental ...understanding of how to manipulate such a fibril assembly and its influence on the BHJ morphology and device performance is crucially important. Here, a series of donor–acceptor polymers, PBT1‐O, PBT1‐S, and PBT1‐C, is used to systematically investigate the relationship between molecular structure, morphology, and photovoltaic performance. The subtle atom change in side chains is found to have profound effect on regulating electronic structure and self‐assembly of conjugated polymers. Compared with PBT1‐O and PBT1‐S, PBT1‐C‐based OSCs show much higher photovoltaic performance with a record fill factor (FF) of 80.5%, due to the formation of optimal interpenetrating network morphology. Such a fibril network strategy is further extended to nonfullerene OSCs using a small‐molecular acceptor, which shows a high efficiency of 12.7% and an FF of 78.5%. The results indicate the formation of well‐defined fibrillar structure is a promising approach to achieving a favorable morphology in BHJ OSCs.
Three novel polymers are synthesized to systematically investigate the relationship between molecular structure, morphology, and photovoltaic performance. A favorable fibrillar network morphology with a narrow polymer fibril width in a PBT1‐C:PC71BM blend leads to a record fill factor exceeding 80%, indicating that the formation of a well‐defined fibrillar structure is a promising approach to achieving a favorable morphology in organic solar cells.
Blockchain technology is developing rapidly and has been applied in various aspects, among which there are broad prospects in Internet of Things (IoT). However, IoT mobile devices are restricted in ...communication and computation due to mobility and portability, so that they can't afford the high computing cost for blockchain mining process. To solve it, the free resources displayed on non-mining-devices and edge cloud are selected to construct collaborative mining network(CMN) to execute mining tasks for mobile blockchain. Miners can offload their mining tasks to non-mining-devices within a CMN or the edge cloud when there are insufficient resources. Considering competition for resource of non-mining-devices, resource allocation problem in a CMN is formulated as a double auction game, among which Bayes-Nash Equilibrium (BNE) is analyzed to figure out the optimal auction price. When offloading to edge cloud, Stackelberg game is adopted to model interactions between edge cloud operator and different CMNs to obtain the optimal resource price and devices' resource demands. The mechanism realizes improving the mining utility in mining networks while ensuring the maximum profit of edge cloud operator. Finally, profits of mining networks are compared with an existing mode which only considers offloading to edge cloud. Under the proposed mechanism, mining networks obtain 6.86% more profits on average.
In this article, by virtue of expansions of two finite products of finitely many square sums, with the aid of series expansions of composite functions of (hyperbolic) sine and cosine functions with ...inverse sine and cosine functions, and in the light of properties of partial Bell polynomials, the author establishes Taylor’s series expansions of real powers of two functions containing squares of inverse (hyperbolic) cosine functions in terms of the Stirling numbers of the first kind, presents a closed-form formula of specific partial Bell polynomials at a sequence of derivatives of a function containing the square of inverse cosine function, derives several combinatorial identities involving the Stirling numbers of the first kind, demonstrates several series representations of the circular constant Pi and its real powers, recovers Maclaurin’s series expansions of positive integer powers of inverse (hyperbolic) sine functions in terms of the Stirling numbers of the first kind, and also deduces other useful, meaningful, and significant conclusions and an application to the Riemann zeta function.
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