Indoor detection of volatile organic compounds (VOCs) concentration is necessary due to the serious toxicity hazards even at trace level. However, physisorbents usually exhibit weak interactions ...especially in the presence of trace concentrations of VOCs, thus exhibiting poor responsive signal. Herein, we report a new flexible metal–organic framework (MOF) that exhibits interesting pore‐opening behavior after immersing in H2O. The pore‐opening phase shows significant (≈116 folds) and extremely fast (<1 minute) fluorescence enhancement after being exposed to saturated benzene vapor. The limit of detection concentration for benzene vapor can be calculated as 0.133 mg L−1. Thus this material represents the first MOF to achieve visual detection of trace benzene vapor by the naked eyes. Theoretical calculations and single‐crystal structure reveal that the special “bilateral π–π stacking” interactions between the host and guest, which facilitate electron transfer and greatly enhance the intensity of fluorescence.
A new flexible metal–organic framework (MOF) exhibits significant and sensitive fluorescence “turn‐on” behavior for benzene vapor by virtue of unique “bilateral π–π stacking” interactions, enabling visual detection of a trace level of benzene for the first time.
The mimicking of both homosynaptic and heterosynaptic plasticity using a high‐performance synaptic device is important for developing human‐brain–like neuromorphic computing systems to overcome the ...ever‐increasing challenges caused by the conventional von Neumann architecture. However, the commonly used synaptic devices (e.g., memristors and transistors) require an extra modulate terminal to mimic heterosynaptic plasticity, and their capability of synaptic plasticity simulation is limited by the low weight adjustability. In this study, a WSe2‐based memtransistor for mimicking both homosynaptic and heterosynaptic plasticity is fabricated. By applying spikes on either the drain or gate terminal, the memtransistor can mimic common homosynaptic plasticity, including spiking rate dependent plasticity, paired pulse facilitation/depression, synaptic potentiation/depression, and filtering. Benefitting from the multi‐terminal input and high adjustability, the resistance state number and linearity of the memtransistor can be improved by optimizing the conditions of the two inputs. Moreover, the device can successfully mimic heterosynaptic plasticity without introducing an extra terminal and can simultaneously offer versatile reconfigurability of excitatory and inhibitory plasticity. These highly adjustable and reconfigurable characteristics offer memtransistors more freedom of choice for tuning synaptic weight, optimizing circuit design, and building artificial neuromorphic computing systems.
The 2D WSe2 based memtransistor with high choice freedom can not only mimic homosynaptic plasticity by applying spikes on either the drain or gate terminal, but also can simulate heterosynaptic plasticity and has numerous merits: 1) no need for adding an extra modulation terminal, 2) versatile reconfigurability of excitatory and inhibitor, and 3) selectivity of input.
The "Clinical Guidelines for Diagnosis and Treatment of Cervical Spondylotic Myelopathy with the Integrated Traditional Chinese and Western Medicine" were formulated by the Orthopedic and ...Traumatology Professional Committee of the Chinese Association of Integrative Medicine in accordance with the principles of evidence-based medicine and expert consensus, and provide clinicians with academic guidance on clinical diagnosis and treatment of CSM. The main content includes diagnostic points, disease grading assessment, TCM syndrome differentiation, surgical indications and timing, integrated traditional Chinese and Western medicine treatment, and postoperative rehabilitation. This guideline proposes for the first time that the treatment of CSM should follow the principle of grading, clarify the timing and methods of surgical treatment, establish common TCM syndrome differentiation and classification, attach importance to postoperative integrated rehabilitation of Chinese and Western medicine, and strengthen daily
The switching variability caused by intrinsic stochasticity of the ionic/atomic motions during the conductive filaments (CFs) formation process largely limits the applications of diffusive memristors ...(DMs), including artificial neurons, neuromorphic computing and artificial sensory systems. In this study, a DM device with improved device uniformity based on well‐crystallized two‐dimensional (2D) h‐BN, which can restrict the CFs formation from three to two dimensions due to the high migration barrier of Ag+ between h‐BN interlayer, is developed. The BN‐DM has potential arrayable feature with high device yield of 88%, which can be applied for building a reservoir computing system for digital pattern recognition with high accuracy rate of 96%, and used as an artificial nociceptor to sense the external noxious stimuli and mimic the important biological nociceptor properties. By connecting the BN‐DM to a self‐made triboelectric nanogenerator (TENG), a self‐power mechano‐nociceptor system, which can successfully mimic the important nociceptor features of “threshold”, “relaxation” and “allodynia” is designed.
The Ag conductive filaments formation can be restricted from three to two dimensions by 2D h‐BN, which can improve the device spatial uniformity significantly. Based on this h‐BN based diffusive memristor, a reservoir computing system for digital pattern recognition and a self‐powered mechano‐nociceptor system for mimicking the important nociceptor features can be successfully built.
Recoveries of cobalt and lithium metals from spent lithium-ion batteries are very important for prevention of environmental pollution and alleviation of resource shortage. In this study, a ...hydrometallurgical route for the recovery of lithium fluoride was proposed. Lithium and cobalt could be first selectively leached into solution using formic acid and hydrogen peroxide. By investigating the effects of leaching temperature, time, stoichiometric ratio, H
2
O
2
concentration and solid-to-liquid ratio, the leaching efficiency of Li and Co could reach 99.90% and 99.96%, respectively. Meanwhile, the evaluation of leaching kinetics and calculation of apparent activation energies revealed that the leaching process fitted chemical control satisfactorily. After further fractional precipitation, a high purity of 99.0% lithium fluoride could be finally obtained, thus achieving the effective recovery of spent material from the lithium-ion battery.
Recoveries of cobalt and lithium metals from spent lithium-ion batteries are very important for prevention of environmental pollution and alleviation of resource shortage.
Sensing of benzene vapor is a hot spot due to the volatile drastic carcinogen even at trace concentration. However, achieving convenient and rapid detection is still a challenge. As a sort of ...functional porous material, metal‐organic frameworks (MOFs) have been developed as detection sensors by adsorbing benzene vapor and converting it into other signals (fluorescence intensity/wavelength, chemiresistive, weight or color, etc.). Supramolecular interaction between benzene molecules and the host framework, aperture size/shape and structural flexibility are influential factors in the performance of MOF‐based sensors. Therefore, enhancing the host‐guest interactions between the host framework and benzene molecules, or regulating the diffusion rate of benzene molecules by changing the aperture size/shape and flexibility of the host framework to enhance the detection signal are effective strategies for constructing MOF‐based sensors. This concept highlights several types of MOF‐based sensors for the detection of benzene vapor.
The development and challenges of benzene vapor sensors based on metal‐organic frameworks (MOFs), which achieve effective detection by virtue of the singal changes in weight, chemiresistive, fluorescence or color after adsorption.
Idiopathic pulmonary fibrosis (IPF) is the most common type of idiopathic interstitial pneumonia and has one of the poorest prognosis. However, the molecular mechanisms underlying IPF progression ...remain largely unknown. In this study, we determined that IL-24, an IL-20 subfamily cytokine member, was increased both in the serum of IPF patients and the bronchoalveolar lavage fluid (BALF) of mice following bleomycin (BLM)-induced pulmonary fibrosis. As a result, IL-24 deficiency protected mice from BLM-induced lung injury and fibrosis. Specifically, loss of IL-24 significantly attenuated transforming growth factor β1 (TGF-β1) production and reduced M2 macrophage infiltration in the lung of BLM-induced mice. Mechanistically, IL-24 alone did not show a perceptible impact on the induction of M2 macrophages, but it synergized with IL-4 to promote M2 program in macrophages. IL-24 suppressed IL-4-induced expression of suppressor of cytokine signaling 1 (SOCS1) and SOCS3, through which it enhanced signal transducer and activator of transcription 6/peroxisome proliferator-activated receptor gamma (STAT6/PPARγ) signaling, thereby promoting IL-4-induced production of M2 macrophages. Collectively, our data support that IL-24 synergizes with IL-4 to promote macrophage M2 program contributing to the development of pulmonary fibrosis.
The quality of the contact between source/drain electrodes and 2D transition metal dichalcogenides plays a decisive role in improving transistor performance. Understanding the mechanisms of Fermi ...level pinning (FLP) and finding out the strategies to solve FLP problems can further promote the development of 2D electronics. In this study, the suppressing effect of MXene on FLP in MoS2 transistors by using Ti3C2Tx as an electrode to build a Ti3C2Tx‐MoS2 heterostructure is systematically studied. A simple and time‐saving ultraviolet ozone technique to tune the work function of the Ti3C2Tx electrode in the range of 4.33–5.32 eV is proposed, and a low Schottky barrier height of 121 meV is achieved. The van der Waals contact between Ti3C2Tx and MoS2 can alleviate the FLP effectively, and the pinning factor can be greatly optimized from 0.28 (metal electrode) to 0.87 (MXene electrode). This study can pave the way for extensive use of MXene and provide a new strategy to eliminate the negative effects of FLP in 2D materials‐based electronic devices.
The use of Ti3C2Tx as an electrode to build Ti3C2Tx‐MoS2 vdWs contact can improve the performance of the 2D field effect transistors, including alleviating the Fermi level pinning and decreasing the Schottky barrier height to 121 eV. Moreover, a simple and time‐saving technique has been proposed to tune the work function of Ti3C2TX electrode in the range of 4.33 to 5.32 eV.
Objectives
Hypoxia is an important risk factor for pulmonary arterial remodelling in pulmonary arterial hypertension (PAH), and the Janus kinase 2 (JAK2) is believed to be involved in this process. ...In the present report, we aimed to investigate the role of JAK2 in vascular smooth muscle cells during the course of PAH.
Methods
Smooth muscle cell (SMC)‐specific Jak2 deficient mice and their littermate controls were subjected to normobaric normoxic or hypoxic (10% O2) challenges for 28 days to monitor the development of PAH, respectively. To further elucidate the potential mechanisms whereby JAK2 influences pulmonary vascular remodelling, a selective JAK2 inhibitor was applied to pre‐treat human pulmonary arterial smooth muscle cells (HPASMCs) for 1 hour followed by 24‐hour hypoxic exposure.
Results
Mice with hypoxia‐induced PAH were characterized by the altered JAK2/STAT3 activity in pulmonary artery smooth muscle cells. Therefore, induction of Jak2 deficiency in SMCs protected mice from hypoxia‐induced increase of right ventricular systolic pressure (RVSP), right ventricular hypertrophy and pulmonary vascular remodelling. Particularly, loss of Jak2 significantly attenuated chronic hypoxia‐induced PASMC proliferation in the lungs. Similarly, blockade of JAK2 by its inhibitor, TG‐101348, suppressed hypoxia‐induced human PASMC proliferation. Upon hypoxia‐induced activation, JAK2 phosphorylated signal transducer and activator of transcription 3 (STAT3), which then bound to the CCNA2 promoter to transcribe cyclin A2 expression, thereby promoting PASMC proliferation.
Conclusions
Our studies support that JAK2 could be a culprit contributing to the pulmonary vascular remodelling, and therefore, it could be a viable target for prevention and treatment of PAH in clinical settings.
Neck pain, sensory disturbance and motor dysfunction in most patients suffered cervical spondylotic myelopathy (CSM). For CSM surgery, it is necessary to evaluate preoperative inter-vertebral disc ...degeneration (IDD) which determines whether to adopt fusion strategy, and postoperative IDD which is one of the main reasons for reoperation. Modified Pfirrmann grading system is commonly used to evaluate IDD. The objective of this study is to evaluate its reliability and reproducibility on cervical IDD in CSM patients, and to explore its clinical application value.
All 165 patients with CSM were enrolled. 6 physicians (3 spine surgeons and 3 radiologists) who have certain clinical experience were selected. They graded cervical inter-vertebral disc according to modified Pfirrmann grading system, we used intra-class correlation coefficient (ICC) and weighted kappa (wκ) to assess the inter- and intra-observer agreement. After 12 weeks, we repeated the analysis.
The inter-observer reliability of modified Pfirrmann grading system was excellent with an ICC value of 0.76 and near perfect with wκ value of 0.82. The intra-observer reproducibility of modified Pfirrmann grading system was excellent with ICC values ranging from 0.80 to 0.91, and near perfect with wκ values ranging from 0.83-0.92.
Modified Pfirrmann grading system has excellent inter-observer reliability and intra-observer reproducibility on cervical IDD in CSM. In addition, it indicates a good appliance among spine surgeons and radiologists, clinical and radiological studies applying it should be deemed accurate. Thus, modified Pfirrmann grading system can be widely used as an appropriate instrument in clinical care.
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