Regulating interface Schottky barriers toward a high-performance self-powered imaging photodetector

Two-dimensional (2D) layered organic–inorganic hybrid perovskites have attracted wide attention in high-performance optoelectronic applications due to their good stability and excellent optoelectronic properties. Here, a high-performance self-powered photodetector is realized based on an asymmetrical metal–semiconductor–metal (MSM) device structure (Pt-(PEA)₂PbI₄ SC-Ag), which introduces a strong built-in electric field by regulating interface Schottky barriers. Benefitting from excellent built-in electrical potential, the photodetector shows attractive photovoltaic properties without any power supply, including high photo-responsivity (114.07 mA W⁻¹), fast response time (1.2 μs/582 μs) and high detectivity (4.56 × 10¹² Jones). Furthermore, it exhibits high-fidelity imaging capability at zero bias voltage. In addition, the photodetectors show excellent stability by maintaining 99.4% of the initial responsivity in air after 84 days. This work enables a significant advance in perovskite SC photodetectors for developing stable and high-performance devices.

A facile method of regulating interface Schottky barriers is used for self-powered photodetectors. Benefitting from the excellent built-in electrical potential, the detector can exhibit high-fidelity imaging capability.     

Wild jujube-based fluorescent carbon dots for highly sensitive determination of oxalic acid

Fluorescent carbon dots (CDs) were synthesized by a one-step hydrothermal treatment of wild jujube and dl-tryptophan. The structure and properties of the CDs were confirmed by transmission electron microscopy, X-ray photoelectron spectroscopy, ultraviolet visible absorption spectroscopy, fluorescence spectroscopy and so on. The as-prepared CDs exhibit excellent excitation-independent but pH-dependent (4.0–12.0) fluorescent features and emit blue strong fluorescence under 365 nm light. Hg²⁺ can decrease the fluorescence intensity of the CDs through static quenching, while the addition of oxalic acid (OA) recovers it owing to the coordination binding between oxalic acid and Hg²⁺. Based on this, the as-prepared CDs were used as a new “off–on” fluorescent probe for highly sensitive determination of oxalic acid with a wide linear detection range of 0.1–20 mg L⁻¹ and a low detection limit of 0.057 mg L⁻¹. Moreover, the fluorescent probe was successfully applied to detect oxalic acid in tomato and cherry tomato samples with satisfactory results.

Carbon dots synthesized from wild jujube and dl-tryptophan can serve as sensitive off–on fluorescent sensors for the detection of oxalic acid.     

Flame retardant chloroprene rubbers with high tensile strength and elongation at break via dual cross-linked networks

The tensile strength and elongation at break of rubbers are mutually restrictive factors. Design and preparation of chloroprene rubber (CR) with high tensile strength, high elongation at break and excellent flame retardancy at the same time is challenging. Melamine cyanurate (MCA) is for the first time discovered to be a reactive flame retardant for CR. The tensile strength of C-M36 (with 3 wt% ZnO and 36 wt% MCA) vulcanizate is 2.5 times that of C-M0 (only with 3 wt% ZnO) vulcanizate, while the elongation at break of C-M36 vulcanizate is 1.3 times that of ZnO cross-linked C-M0 vulcanizate. At the same time, the limiting oxygen index of C-M36 (39%) is 1.22 times that of C-M0 (32%). FTIR and the vulcanization tests confirm that the reaction between CR and cyanuric acid occurs under the catalysis of a base (melamine), and the cyanuric acid molecules are grafted onto the molecular chain of CR. Two types of crosslinking networks are formed in CR vulcanizate, namely the traditional covalent bond crosslinks and the triple hydrogen crosslinks formed between cyanuric acid and melamine. Thus, the flame-retardant CR/MCA vulcanizate with high strength and high elongation at break is obtained. This research will strongly promote the industrial application of CR.

Melamine cyanurate served as a reactive flame retardant crosslinker for chloroprene rubbers.     

Preparation and performance study of a reactive polyurethane hot-melt adhesive/CS–Fe3O4 magnetic nanocomposite film/fabric

Magnetic nanoparticles are attracting significant attention for their wide application as biomaterials and magnetic storage materials. As an environmentally friendly adhesive, reactive polyurethane hot-melt adhesive (PUR) is a biocompatible polymer with a wide range of applications. In this paper, chitosan (CS)-surface-modified magnetic Fe₃O₄ nanoparticles were synthesized by the sol–gel method. Surface modification of the Fe₃O₄ nanoparticles with CS enhanced their mechanical properties in PUR. The nanoparticles were characterized by Fourier transform infrared (FTIR) and X-ray diffraction (XRD) analyses, while their surface morphology was elucidated using scanning electron microscopy (SEM) and projection electron microscopy (TEM) techniques. Subsequently, PUR/CS–Fe₃O₄ magnetic nanocomposite films were prepared using an in situ method, wherein different amounts of CS–surface-modified magnetic Fe₃O₄ nanoparticles were doped into the PUR and coated on the films. The thermal, UV resistance and mechanical properties of the PUR/CS–Fe₃O₄ magnetic nanocomposite films were investigated by TGA, UV spectrometer and tensile testing. CS–Fe₃O₄ nanoparticles were successfully prepared using the sol–gel method and CS to modify the surface of the Fe₃O₄ nanoparticles. The results show that the mechanical properties and UV resistance of PUR/CS–Fe₃O₄ magnetic nanocomposites are improved by almost 50%, so the constructed PUR/CS–Fe₃O₄ magnetic nanocomposites have good UV-resistant properties and mechanical properties. The as-synthesized CS–Fe₃O₄ magnetic nanocomposites show great potential for application to mechanical and textile development.

Magnetic nanoparticles are attracting significant attention for their wide application as biomaterials and magnetic storage materials. As an environmentally friendly adhesive, reactive polyurethane hot-melt adhesive is a biocompatible polymer with a range of applications.     

IL-20RB mediates tumoral response to osteoclastic niches and promotes bone metastasis of lung cancer

Bone is a common site of metastasis in lung cancer, but the regulatory mechanism remains incompletely understood. Osteoclasts are known to play crucial roles in osteolytic bone metastasis by digesting bone matrix and indirectly enhancing tumor colonization. In this study, we found that IL receptor 20 subunit β (IL-20RB) mediated a direct tumoral response to osteoclasts. Tumoral expression of IL-20RB was associated with bone metastasis of lung cancer, and functionally, IL-20RB promoted metastatic growth of lung cancer cells in bone. Mechanistically, tumor cells induced osteoclasts to secrete the IL-20RB ligand IL-19, and IL-19 stimulated IL-20RB–expressing tumor cells to activate downstream JAK1/STAT3 signaling, leading to enhanced proliferation of tumor cells in bone. Importantly, blocking IL-20RB with a neutralizing antibody significantly suppressed bone metastasis of lung cancer. Overall, our data revealed a direct protumor role of osteoclastic niche in bone metastasis and supported IL-20RB–targeting approaches for metastasis treatment.     

Apelin-13对高尿酸诱导的脂肪细胞氧化应激的作用

目的:探讨apelin-13对高尿酸诱导的3T3-L1脂肪细胞氧化应激的作用及其机制。方法:3T3-L1脂肪细胞予以10 mg/dL尿酸刺激,部分细胞予以1μmol/L apelin-13预处理,以100μmol/L H₂O₂刺激的细胞为阳性对照。48 h后,流式细胞术检测活性氧族(ROS)含量,生化试剂盒检测细胞及培养液上清抗氧化酶[超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)和过氧化氢酶(CAT)]和促氧化酶NADPH氧化酶(NOX)的活性以及丙二醛(MDA)含量,real-time PCR法检测细胞局部肾素-血管紧张素系统(RAS)各组份血管紧张素原(AGT)、血管紧张素转化酶I(ACE1)、血管紧张素II 1型受体(AT1R)和AT2R及血管紧张素II 1型受体相关蛋(APJ)的mRNA表达水平,ELISA法检测细胞及培养液中血管紧张素II(AngⅡ)浓度。结果:10 mg/dL的尿酸明显降低3T3-L1脂肪细胞SOD、GSH-Px和CAT的活性,升高NOX的活性,增加MDA的含量,细胞内ROS的含量相应升高;apel...     

小鼠海马结构与脊髓损伤后抑郁症高发病率的关系研究

目的:探究脊髓损伤引发的抑郁高风险率是否与海马生理结构的改变有关。方法:制作小鼠脊髓损伤模型,分别在损伤后不同时期采用Basso Mouse Scale(BMS)评分对小鼠术后运动功能进行评估;并通过糖水偏好实验和悬尾实验评估小鼠的抑郁情况;HE染色观察海马组织内部细胞的变化;电镜观察海马亚细胞结构突触的结构变化;RT-qPCR检测突触蛋白标志物突触小泡蛋白(SYP)和突触后致密蛋白95(PSD-95)在mRNA水平上的变化。结果:行为学实验显示模型组小鼠有显著的抑郁行为,且在第7天抑郁程度最显著(P<0.01);HE染色显示,与对照组相比,模型组海马细胞排列紊乱,数量减少,形态欠规则;电镜结果显示,与对照组相比,模型组海马超微结构突触数量减少,突触活动区长度变短,突触后致密物厚度变薄,突触间隙宽度增加,突触界面曲率减小(P<0.05);RT-qPCR结果显示模型组SYP和PSD-95 mRNA表达水平较对照组降低(P<0.05)。结论:海马生理结构的改变是脊髓损伤后抑郁症高风险的原因之一。     

Retinal oxygen kinetics imaging and analysis (ROKIA) based on the integration and fusion of structural-functional imaging

The retina is one of the most metabolically active tissues in the body. The dysfunction of oxygen kinetics in the retina is closely related to the disease and has important clinical value. Dynamic imaging and comprehensive analyses of oxygen kinetics in the retina depend on the fusion of structural and functional imaging and high spatiotemporal resolution. But it’s currently not clinically available, particularly via a single imaging device. Therefore, this work aims to develop a retinal oxygen kinetics imaging and analysis (ROKIA) technology by integrating dual-wavelength imaging with laser speckle contrast imaging modalities, which achieves structural and functional analysis with high spatial resolution and dynamic measurement, taking both external and lumen vessel diameters into account. The ROKIA systematically evaluated eight vascular metrics, four blood flow metrics, and fifteen oxygenation metrics. The single device scheme overcomes the incompatibility of optical design, harmonizes the field of view and resolution of different modalities, and reduces the difficulty of registration and image processing algorithms. More importantly, many of the metrics (such as oxygen delivery, oxygen metabolism, vessel wall thickness, etc.) derived from the fusion of structural and functional information, are unique to ROKIA. The oxygen kinetic analysis technology proposed in this paper, to our knowledge, is the first demonstration of the vascular metrics, blood flow metrics, and oxygenation metrics via a single system, which will potentially become a powerful tool for disease diagnosis and clinical research.     

缺血性脑卒中患者中医证型与Crouse积分、血清同型半胱氨酸、凝血功能相关性研究

目的:探讨缺血性脑卒中患者中医证型与Crouse积分、血清同型半胱氨酸(Hcy)、凝血功能的相关性.方法:选取缺血性脑卒中患者96例作为研究对象,对其临床资料、中医证型、实验室检查及颈动脉超声检查结果进行回顾性分析.分析96例入组患者的中医证型分布,比较不同中医证型患者的Crouse积分、血清Hcy、国际标准化比率(I...     

人参皂苷Rb1激活蛋白酪氨酸激酶2/信号传导及转录激活蛋白3通路减轻川崎病小鼠心肌损伤

目的:探讨人参皂苷Rb1对川崎病小鼠心肌损伤的治疗作用及其信号通路。方法:将5～6周龄BALB/C小鼠随机分为对照组、模型组、阿司匹林组、人参皂苷Rb1低剂量组(50 mg/kg)和高剂量组(100 mg/kg),每组12只。除对照组外,其他各组均间断性腹腔注射10%牛血清白蛋白生理盐水溶液,以诱发川崎病心肌损伤病理模...