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Direct analysis in real time (DART) enables direct desorption and ionization of analytes, bypassing the time-consuming chromatographic separation traditionally required for mass spectrometry (MS) analysis. However, DART-MS suffers from matrix interference of complex samples, resulting in compromised detection sensitivity and quantitation accuracy. In this study, DART-MS was combined with differential mobility spectrometry (DMS) to provide an additional dimension of post-ionization ion mobility separation within a millisecond time scale, compensating for the lack of separation in DART-MS analysis. As proof-of-concept, primary aromatic amines (PAAs), a class of potentially hazardous chemicals, were analyzed in various toy products, including bubble solutions, finger paints, and plush toys. In addition to commercial Dip-it glass rod and metal mesh sampling tools, a customized rapid extractive evaporation device was designed for the accelerated extraction and sensitive analysis of solid toy samples. The incorporation of DMS in DART-MS analysis enabled the rapid separation and differentiation of isomeric analytes, leading to improved accuracy and reliability. The developed protocols were optimized and validated, achieving good linearity with correlation coefficients greater than 0.99 and acceptable repeatability with relative standard deviations less than 10%. Moreover, satisfactory sensitivity was realized with limits of detection and quantitation ranges of 0.2–5 and 1–20 μg/kg (μg/L) for the 11 PAA analytes. The established methodology was applied for the analysis of real toy samples (n= 18), which confirmed its appealing potential for toy safety screening and consumer health protection.

Fusarium crown rot of wheat (FCR) is mainly caused by Fusarium pseudograminearumand is a major disease in the Huang-huai wheat growing region in China, leading to a potential yield loss. In order to evaluate the effect of pyraclostrobin on the growth of F. pseudograminearumand its control efficacy, the inhibitory activity of pyraclostrobin against the growth of F. pseudograminearumwas studied, and field trials of pyraclostrobin against FCR was carried out. The results showed that pyraclostrobin had strong inhibitory effect on four growth stages of F. pseudograminearum. The EC50value of pyraclostrobin to mycelial growth was 0.1168–10.3378 μg/mL with an average of (3.5348 ± 3.0044) μg/mL, and with the shortening of branch spacing, the branching number increased as well as the bending of the hyphal apex at the edge of the mycelia. The EC50value of pyraclostrobin on conidial germination was 0.0052–0.2498 μg/mL with an average of (0.0782 ± 0.0504) μg/mL, and there was an increased chance that conidia will germinate from intermediate cells. The EC50value of pyraclostrobin on germ tube elongation was 0.0244–0.0605 μg/mL, which could make the middle cells of the conidia to swell and become deformed, but the teratogenic effect on the germ tube was not obvious. Pyraclostrobin can delay conidia sporulation time and make the conidia cells enlarged and deformed. The EC50value of sporulation was 0.0170–0.0225 μg/mL. The results of field trials in Xin'an County and Yichuan County of Luoyang City showed that compared with carbendazim, pyraclostrobin had higher control effect on FCR at the jointing stage and the filling stage, with the control effect being more than 50%. It also reduced the rate of white spikes of wheat at the milky stage, but the control effect of pyraclostrobin at the filling stage decreased. At the same time, pyraclostrobin soaking increased the plant height, stem girth and 1,000 grain weight of wheat. Pyraclostrobin could be used as an alternative fungicide in the integrated management of FCR.

Selenoprotein thioredoxin reductase 1 (TXNRD1) is a promising therapeutic target, with several inhibitors reported to inhibit TXNRD1 activity. These inhibitors have the potential for applications such as anti-tumor medications. Here, we present a protocol for assessing irreversible inhibitors of TXNRD1. We describe four assays covering cellular TXNRD activity measurement, recombinant enzyme-based activity determination, differential scanning fluorimetry (DSF), and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. This protocol will facilitate the screening and development of potential small-molecule inhibitors of TXNRD1.

Harvesting radio frequency (RF) energy from the environment to power electronic devices has gradually become a mature technology. With the continuous research and development of radio frequency energy harvesting (RFEH) system, it has been expected to replace the battery and applied in wireless sensor networks, wearable devices, Internet of Things and environmental monitoring, etc. However, the performance of RFEH system is limited by the low power conversion efficiency (PCE), narrow dynamic range (DR) and low output voltage of circuits, etc. In this paper, the recent progress and development of RFEH devices and circuits are systematically reviewed. In the RFEH system, antenna is used to receive RF energy, which mainly includes multiband antennas, multiport antennas and array antennas. The impedance matching networks, including the lumped parameter and distributed matching networks, are used for matching the impedance between the antenna and rectifier to achieve maximum power transfer. Non-CMOS, Dickson and Cross-coupled-differential-drive rectifiers are used to convert the received RF signal into dc voltage. The power management unit is adopted to achieve adaptive control, the startup of rectifier, and power conversion. In addition, the comparisons and discussion on the structure, process and performance of RFEH devices and circuits are presented to provide valuable guidance for designing and manufacturing high performance RFEH system. Finally, an outlook on RFEH system is presented, which includes improving the PCE, extending the bandwidth and input DR, and developing accurate optimization design methodology.

Janus nanoparticles with an anisotropic feature concentrated multiple properties on a single carrier, providing synergistic effects. In this study, dual-functionalized Janus nanoparticles (HA-JMSN/DOX-DMMA) were constructed with a tumor-targeting ligand (hyaluronic acid, HA) modified on the one side and a charge reversal group (2,3-dimethylmaleic anhydride, DMMA) on the other side. The drug release of HA-JMSN/DOX-DMMA was positively correlated with the acidity of the environment. The cytotoxicity and cell uptake of HA-JMSN/DOX-DMMA were superior to the isotropous nanoparticles. The endocytosis pathway of HA-JMSN/DOX-DMMA involved the clathrin-mediated endocytosis (HA) and the micropinocytosis (DMMA) at the same time, which indicated that they both participated in the interaction between nanoparticles and tumor cells. After being injected intravenously in mice, the distribution of HA-JMSN/DOX-DMMA in tumor was enhanced significantly. The antitumor therapy study in vivo showed that HA-JMSN/DOX-DMMA inhibited tumor growth and improved the survival rate of tumor-bearing mice effectively. In general, HA-JMSN/DOX-DMMA could take the synergistic effect of active targeting and charge reversal to deliver drug in tumor cells and kill them efficiently, which was a promising antitumor nanodrug.

Transportation of exogenous copper ions into cancer cells by copper carriers has gained increasing interest for cancer chemotherapy. We disclosed herein a redox-dependent copper carrier, 2,2′-dithiodipyridine (DPy), which binds copper ions and carries the cargo into cells. The cellular reducing environment cleaved the disulfide bond in DPy to facilitate unloading copper ions. The elevated copper level then elicits oxidative stress and subsequently promotes the reformation of DPy. Further mechanistic studies revealed that the DPy/copper combination predominantly targets the cellular redox-regulating systems, including the thioredoxin system and the glutathione system, to induce the oxidative stress-mediated death of tumor cells. The discovery of DPy as a cleavable and recyclable copper shuttle provides a proof of concept for designing novel biomaterials for copper transportation as potential anticancer agents.

Objective To identify the prognostic factors for local recurrence of giant cell tumor of bone (GCTB) through assessment of the preoperative imaging features of the tumor border.Methods Patients with GCTBs treated with intralesional procedures in the proximal tibia and distal femur were prospectively enrolled and then followed up for at least 2 years. The GCTBs were grouped according to their preoperative imaging features. GCTBs treated with en bloc resection were enrolled for investigation of the pathologic basis of specific imaging features. Differences between rates were evaluated by the chi-square test or Fisher’s exact test; independent factors were identified by multivariate logistic regression analysis.Results Fifty-three patients were enrolled and successfully followed up. Relapse occurred in 22 patients. Patients with a “paintbrush borders” sign (n = 21) had a significantly higher rate of local recurrence (71.43%) than patients without this sign (21.88%). The “paintbrush borders” sign was identified as an independent prognostic factor for local recurrence. Other imaging features were not significantly associated with recurrence. The “paintbrush borders” sign showed a correlation with local invasion of bone.Conclusion The “paintbrush borders” sign on preoperative magnetic resonance imaging is an independent prognostic factor for local recurrence of GCTB.

Engineering scaffolds with excellent electro-activity is increasingly important in tissue engineering and regenerative medicine. Herein, conductive poly(3,4-ethylenedioxythiophene) doped with hyaluronic acid (PEDOT-HA) nanoparticles were firstly synthesized viachemical oxidant polymerization. A three-dimensional (3D) PEDOT-HA/Cs/Gel scaffold was then developed by introducing PEDOT-HA nanoparticles into a chitosan/gelatin (Cs/Gel) matrix. HA, as a bridge, not only was used as a dopant, but also combined PEDOT into the Cs/Gel viachemical crosslinking. The PEDOT-HA/Cs/Gel scaffold was used as a conductive substrate for neural stem cell (NSC) culture in vitro. The results demonstrated that the PEDOT-HA/Cs/Gel scaffold had excellent biocompatibility for NSC proliferation and differentiation. 3D confocal fluorescence images showed cells attached on the channel surface of Cs/Gel and PEDOT-HA/Cs/Gel scaffolds with a normal neuronal morphology. Compared to the Cs/Gel scaffold, the PEDOT-HA/Cs/Gel scaffold not only promoted NSC proliferation with up-regulated expression of Ki67, but also enhanced NSC differentiation into neurons and astrocytes with up-regulated expression of β tubulin-III and GFAP, respectively. It is expected that this electro-active and bio-active PEDOT-HA/Cs/Gel scaffold will be used as a conductive platform to regulate NSC behavior for neural tissue engineering.

Crowd counting is recently becoming a hot research topic, which aims to count the number of the people in different crowded scenes. Existing methods are mainly based on training-testing pattern and rely on large data training, which fails to accurately count the crowd in real-world scenes because of the limitation of model’s generalization capability. To alleviate this issue, a scene-adaptive crowd counting method based on meta-learning with Dual-illumination Merging Network (DMNet) is proposed in this paper. The proposed method based on learning-to-learn and few-shot learning is able to adapt different scenes which only contain a few labeled images. To generate high quality density map and count the crowd in low-lighting scene, the DMNet is proposed, which contains Multi-scale Feature Extraction module and Element-wise Fusion Module. The Multi-scale Feature Extraction module is used to extract the image feature by multi-scale convolutions, which helps to improve network accuracy. The Element-wise Fusion module fuses the low-lighting feature and illumination-enhanced feature, which supplements the missing illumination in low-lighting environments. Experimental results on benchmarks, WorldExpo’10, DISCO, USCD, and Mall, show that the proposed method outperforms the existing state-of-the-art methods in accuracy and gets satisfied results.

Although carina shift and plaque shift are suggested as mechanisms of side branch ostial (SBo) compromise after main vessel (MV) stenting in bifurcation lesions, there are few direct evidence. Our purpose was to confirm the mechanism of SBo compromise after MV stent implantation.