Silicon is one of the most promising anode materials for lithium‐ion batteries because of the highest known theoretical capacity and abundance in the earth' crust. Unfortunately, significant ...“breathing effect” during insertion/deinsertion of lithium in the continuous charge‐discharge processes causes the seriously structural degradation, thus losing specific capacity and increasing battery impedance. To overcome the resultant rapid capacity decay, significant achievements has been made in developing various nanostructures and surface coating approaches in terms of the improvement of structural stability and realizing the long cycle times. Here, the recent progress in surface and interface engineering of silicon‐based anode materials such as core‐shell, yolk‐shell, sandwiched structures and their applications in lithium‐ion batteries are reviewed. Some feasible strategies for the structural design and boosting the electrochemical performance are highlighted. Future research directions in the field of silicon‐based anode materials for next‐generation lithium‐ion batteries are summarized.
Silicon‐based materials are recognized as the most promising anode materials because of the highest theoretical capacity. However, many critical challenges such as losing specific capacity and increasing battery impedance during continuous charge‐discharge processes strongly hindered the further application. In this review, the recent progress to utilize surface and interface engineering strategies to overcome these problems is summarized.
Flexible and wearable chemical sensors show great capability and potential in retrieving physiologically related chemical or biochemical information from elastic and curvilinear living bodies. ...However, so far, no flexible electrochemiluminescence (ECL) device has been reported, though ECL measurements have been extensively investigated and widely applied in many fields. Herein, we for the first time designed and fabricated a flexible ECL sensor by immobilizing highly luminescent nanospheres on Au nanotube (Au NT) networks, and subsequently coating an elastic molecularly imprinted polymer (MIP) thereon. The as-prepared flexible ECL platform displayed successive and desirable mechanical compliance while generating a very stable ECL signal during deformation, facilitating highly selective detection of physiologically relevant chemicals from bodies. On-body wearable sampling and subsequent detection of lactate and urea from sweat showed the ECL performance of this sensor displaying desirable fidelity, reusability and high stability against disturbance. This work successfully incorporated the ECL sensing model into a flexible and wearable device, therefore providing a promising new path for non-invasively monitoring the products of metabolism for health care and biomedical investigations.
Flexible and wearable electrochemiluminescence sensor was successfully designed and fabricated for non-invasively monitoring the metabolism products in sweat.
Distributed coherent aperture radar (DCAR) is a critical advancement in next-generation radar technology. Traditional DCAR relies on quadrature signals to gather target parameters before transmitting ...coherent signals, facing the challenge of time synchronization and parameter acquisition accuracy. This article tackles the challenges by transforming the coherence problem into an optimization issue, achieved by quantifying the degree of coherence of the echo signal. We employ an optimization algorithm to adjust the transmission time of each node, thereby ensuring that signals coherently accumulate at the target location. Furthermore, we propose a smoothing optimization technique to counter the fitness function's "multipeak" and "black box" attributes. By employing the barycentric interpolation to construct a pseudofunction, this technique facilitates the smoothing of the fitness function, speeds up convergence, and minimizes the probability of falling in local optima. For scenarios involving moving targets, a Kalman filter is embedded within the optimization algorithm to facilitate target motion prediction and preemptively resolve temporal errors in parameter acquisition, thereby enhancing real-time tracking capabilities. Theoretical analyses and simulation results demonstrate the efficacy of the proposed method in facilitating coherent target tracking. This method improves the signal-to-noise ratio while reducing the need for precise carrier synchronization. In addition, the proposed smoothing optimization technique accelerates convergence rates, reduces the possibility of convergence to a local optimum, and can be applied to optimization problems with similar properties.
Large deformation of soft rock roadway has always been a major difficulty in deep mining practices. This paper describes a case study of the failure mechanisms and stability control technology of ...deep roadway with soft rock mass in Xin'an coal mine in Gansu Province, China. Rock mass properties around the roadway are evaluated using geological strength index (GSI) based on the field data and the mechanical properties of intact rock specimens. The Universal Discrete Element Code (UDEC) software program is adopted to establish the numerical model of a ventilation roadway in Xin'an coal mine, and the micro-parameter calibration is conducted with the rock mass properties. The failure process of roadway under unsupported and primary support conditions is simulated; the deformation, stress and crack evolution characteristics were clearly illustrated. Failure first appears around the roadway surface because there is a high stress concentration around the roadway surface after excavation; the failure area propagates further into the deep surrounding rock as the stresses applied on the surface gradually decreases, finally resulting in a large zone of stress relaxation. There exists a large scale of tensile failure in the shallow rock, which leads to swelling and fracturing around the roadway. The primary support is low in strength with no support in the floor, which results in serious floor heave, side shrinking and roof subsidence. A new “bolt-cable-mesh-shotcrete+shell” combined support is proposed to support the ventilation roadway. The monitoring data in the experiment section show that the new support design successfully controls the large deformation of the roadway, which can provide helpful references for support designing of engineering in deep soft rock roadway.
•Evaluate rock mass properties around the roadway using GSI.•Establish the numerical model of a ventilation roadway in Xin'an coal mine using UDEC.•Obtain the deformation and stress behavior of roadway under various support conditions.•Analyze the crack evolution process of roadway under various support conditions.•Propose and validate a new “bolt-cable-mesh-shotcrete+shell” combined support mode.
MicroRNAs (miRNAs) have been perceived as important regulators in multifarious biological processes as well as potential biomarkers in clinical diagnosis. Exploring high-efficient sensing platforms ...for tracing miRNAs in complex biological samples is of great vital. Herein, an ultrasensitive and enzyme-free electrochemical biosensor was constructed based on integration of efficiently catalytic electrochemical−chemical−chemical (ECC) redox cycling with target-induced magnetic DNAzyme walker. Employing porous and easily functionalized covalent organic framework (COF) as carriers, Pt@COF nanospheres (Pt@COF NSs) were facilely prepared by in-situ reduction of platinum precursors in the nanopores-structure of COF. This not only addressed the inevitable migration of pure Pt nanoparticles, but endowed Pt@COF NSs with desirable stability and excellent catalytic activity to boost ECC redox cycling for effective signal enhancement. On this basis, a target-induced magnetic DNAzyme walker was obediently induced to recognize, separate and convert low-abundant miRNA-21 targets into plentiful output DNA chains for accumulated signal amplification. Finally, the as-prepared robust biosensor manifested highly sensitive and selective determination of miRNA-21 with a wide detection range from 100 aM to 10 pM and a low detection limit of 47.5 aM. Meanwhile, the credible detectability and anti-interference were also demonstrated in serum and cell samples, indicating its promising application toward diseases warning.
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•Pt@COF nanocatalyst was gained by in-situ growth of Pt in porous COF carriers.•The catalytic Pt@COF-based redox cycling greatly boosted electrochemical signal.•A magnetic DNAzyme walker achieved miRNA-21 recognition, separation and conversion.•This signal amplification system was used for ultrasensitive miRNA-21 detection.
Disinfection is an indispensable water treatment process for killing harmful pathogens and protecting human health. However, the disinfection has caused significant public concern due to the ...formation of toxic disinfection by-products (DBPs). Lots of studies on disinfection and DBPs have been performed in the world since 1974. Although related studies in China started in 1980s, a great progress has been achieved during the last three decades. Therefore, this review summarized the main achievements on disinfection and DPBs studies in China, which included: (1) the occurrence of DBPs in water of China, (2) the identification and detection methods of DBPs, (3) the formation mechanisms of DBPs during disinfection process, (4) the toxicological effects and epidemiological surveys of DBPs, (5) the control and management countermeasures of DBPs in water disinfection, and (6) the challenges and chances of DBPs studies in future. It is expected that this review would provide useful information and reference for optimizing disinfection process, reducing DBPs formation and protecting human health.
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Programmed cell death protein 1 (PD-1) is one of the coinhibitory checkpoints upon T cell activation, the abnormal expression of which severely threatens host immune modulatation for chronic ...infection. Thus, fast and sensitive monitoring of PD-1 is of vital importance for early diagnosis and cancer treatment. The current detection methods largely based on enzyme-linked immunosorbent assay (ELISA) require time-consuming incubation and complicated washing steps. Herein, we designed a simple and portable nanofiber paper (NFP)-based fluorescence “off-on” immunosensor for PD-1 rapid determination. Molybdenum disulfide (MoS2) nanosheets modified NFP (MoS2–NFP) was employed for adsorbing and immobilizing CdSe/ZnS quantum dots-antibody (QDs-Ab) complex to construct a ready-to-use fluorescent immunosensor. The fluorescent signal of QDs-Ab was initially quenched by MoS2 under the Förster resonance energy transfer (FRET) effect. When the PD-1 target was specifically captured onto NFP by immunization, the QDs-Ab-PD-1 complex was promptly desorbed from the MoS2–NFP surface, resulting in FRET impediment and fluorescence recovery. As an alternative quenching agent, graphene oxide (GO) served as a contrast to investigate NFP-based sensing performance. Owing to superior quenching and desorption efficiency, the MoS2–NFP-based fluorescence immunosensor exhibited nearly 2-fold lower detection limit (85.5 pg/mL) than GO–NFP-based sensor (151 pg/mL) for PD-1 monitoring. Excellent selectivity and satisfactory recovery in PD-1 mouse cell culture supernatant samples were confirmed as well. In addition, the comparable detectability of the MoS2–NFP-based immunosensor was accurately evaluated by a standard PD-1 mouse ELISA kit. This study displayed a simple, rapid, low-cost, and portable point-of-care PD-1 assay, indicating its broad application prospect toward clinical diagnoses.
Malnutrition has been reported to be associated with reduced survival and deficient anticancer immunity, and undernourishment is a frequent comorbidity in head and neck cancer (HNC) patients. In this ...study, we evaluated the relationship between nutritional status and immunologic factors, and its prognostic value for HNC. We retrospectively reviewed 212 HNC patients who had undergone a nutrition evaluation based on the Patient‐Generated Subjective Global Assessment (PG‐SGA) and curative radiotherapy (RT). The role of nutritional status in the prognosis of HNC and its correlation with anticancer immune response was assessed in HNC patients, and in the 4‐nitroquinoline 1‐oxide (4NQO)‐induced tongue tumor animal model. Our data revealed that malnutrition (high PG‐SGA scores) was significantly associated with more advanced disease, lower body mass index, lower RT completion rates, and reduced survival. Patients in the group with high PG‐SGA scores had a higher neutrophil‐to‐lymphocyte ratio, higher proportion of myeloid‐derived suppressor cells (MDSCs), and elevated IL‐6 levels in the peripheral circulation. Patients with increased PG‐SGA scores following treatment were more likely to developing locoregional failure. In the 4NQO‐induced tumor model, nutritional supplementation decreased the rate of invasive tumor formation and attenuated the immune‐suppressive microenvironment. Following ectopic tumor implantation in an immunocompetent host, nutrition supplements decreased tumor growth in association with attenuated MDSC recruitment and lower IL‐6 expression. In conclusion, malnutrition by PG‐SGA was associated with poor prognosis in HNC patients. Based on the data of HNC patients and the 4NQO‐tumor model, adequate nutritional supplementation might improve the prognosis associated with augmented anticancer immunity.
The transient receptor potential vanilloid type 4 (TRPV4) channel, a Ca2+‐permeable nonselective cation channel, is widely distributed in the circulatory system, particularly in vascular endothelial ...cells (ECs) and smooth muscle cells (SMCs). The TRPV4 channel is activated by various endogenous and exogenous stimuli, including shear stress, low intravascular pressure, and arachidonic acid. TRPV4 has a role in mediating vascular tone and arterial blood pressure. The activation of the TRPV4 channel induces Ca2+ influx, thereby resulting in endothelium‐dependent hyperpolarization and SMC relaxation through SKCa and IKCa activation on ECs or through BKCa activation on SMCs. Ca2+ binds to calmodulin, which leads to the production of nitric oxide, causing vasodilation. Furthermore, the TRPV4 channel plays an important role in angiogenesis and arteriogenesis and is critical for tumor angiogenesis and growth, since it promotes or inhibits the development of various types of cancer. The TRPV4 channel is involved in the active growth of collateral arteries induced by flow shear stress, which makes it a promising therapeutic target in the occlusion or stenosis of the main arteries. In this review, we explore the role and the potential mechanism of action of the TRPV4 channel in the regulation of vascular tone and in the induction of neovascularization to provide a reference for future research.
In this paper, a joint direction of arrival (DOA) and distance estimation (JDDE) method using a novel time-domain wideband synthesis signal system is proposed. In contrast to traditional time-domain ...synthesis methods, which transmit sub-pulses separately, a uniform linear array is used, and all stepped linear frequency modulated (SLFM) sub-pulses are transmitted simultaneously. The echo signal is mixed with each transmitted signal of the corresponding antenna and filtered to separate the single-frequency components from different targets and array elements for synthesis. Single-frequency components have different frequencies and discontinuous phases due to wave-way differences. To solve the problem that single-frequency components cannot be synthesized directly, the frequency and phase of single-frequency components need to be calibrated, including frequency conversion and phase shift, which require DOA information of the targets. Consequently, a high-precision DOA algorithm that employs phase difference fitting, along with the corresponding generic phase unwrapping algorithm, is designed for the characteristics of the arrays and signal system in this paper. After obtaining the DOA information, the wideband synthesis algorithm is applied to synthesize the single-frequency components to obtain high-resolution ranging results. The theoretical analysis and simulation results show that the method has high distance resolution and JDDE accuracy. In a multi-target environment, the number of targets is not limited by the number of antennas. In addition, unlike traditional wideband synthesis methods, the method utilizes multiple transmitting antennas to send SLFM signal pulses simultaneously rather than sequentially, which enhances the response speed of the radar.
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