Collaborative Camouflaged Object Detection: A Large-Scale Dataset and Benchmark

In this paper, we provide a comprehensive study on a new task called collaborative camouflaged object detection (CoCOD), which aims to simultaneously detect camouflaged objects with the same properties from a group of relevant images. To this end, we meticulously construct the first large-scale dataset, termed CoCOD8K, which consists of 8,528 high-quality and elaborately selected images with object mask annotations, covering 5 superclasses and 70 subclasses. The dataset spans a wide range of natural and artificial camouflage scenes with diverse object appearances and backgrounds, making it a very challenging dataset for CoCOD. Besides, we propose the first baseline model for CoCOD, named bilateral-branch network (BBNet), which explores and aggregates co-camouflaged cues within a single image and between images within a group, respectively, for accurate camouflaged object detection in given images. This is implemented by an inter-image collaborative feature exploration (CFE) module, an intra-image object feature search (OFS) module, and a local-global refinement (LGR) module. We benchmark 18 state-of-the-art models, including 12 COD algorithms and 6 CoSOD algorithms, on the proposed CoCOD8K dataset under 5 widely used evaluation metrics. Extensive experiments demonstrate the effectiveness of the proposed method and the significantly superior performance compared to other competitors. We hope that our proposed dataset and model will boost growth in the COD community. The dataset, model, and results will be available at: https://github.com/zc199823/BBNet--CoCOD.Comment: Accepted by IEEE Transactions on Neural Networks and Learning Systems (TNNLS

Highly expressed circ_0000285 from serum and cervical exfoliated cells as a novel biomarker for the diagnosis of early stage-cervical cancer

Circ_0000285 is reported to play an oncogenic role in the development of cervical cancer (CC). The aim of this research was to investigate the diagnostic power of circ_0000285 in CC. The expression of circ_0000285 in 116 healthy volunteers, 65 early-stage CC (ESCC) patients, and 87 locally advanced CC (LACC) patients was detected by qRT-PCR. The diagnostic values of circ_0000285 for CC and ESCC were evaluated by ROC curves analysis. The circ_0000285 expression was upregulated in serum and cervical exfoliated cells from preoperative CC patients compared to that of healthy volunteers. Increased circ_0000285 expression was found in preoperative LACC patients more than that in ESCC patients. The circ_0000285 expression was downregulated in serum from CC patients after surgery. The postoperative CC patients with high serum circ_0000285 expression was more prone to have a tumour relapse. High circ_0000285 expression was positively correlated with SCC-Ag level and HPV positive rate. The AUC of circ_0000285 for the diagnosis of CC and ESCC were 0.855 and 0.804, better than CA125 and SCC-Ag. When circ_0000285, CA125, SCC-Ag and HPV were combined, the AUC could reach 0.911 and 0.894. In summary, highly expressed circ_0000285 from serum and cervical exfoliated cells might be a promising diagnostic biomarker for ESCC.Impact statement What is already known on this subject? The CA125 and SCC-Ag have limitations in the diagnosis of ESCC. Recently, circRNAs have caused great attention and have been developing rapidly in clinical diagnosis of malignant tumours. What do the results of this study add? Highly expressed circ_0000285 from serum and cervical exfoliated cells might be used as a novel, non-invasive biomarker for the diagnosis of ESCC. What are the implications of these findings for clinical practice and/or further research? Circ_0000285 is superior to CA125 and SCC-Ag for the diagnosis of ESCC in clinical practice. The results help to supplement the shortcomings of traditional tumour markers and improve the diagnosis of ESCC

Nanoengineering of N-doped Mesoporous Carbon Nanoparticles with Adjustable Internal Cavities via Emulsion-Induced Assembly

The preparation of mesoporous carbonaceous materials with particularly adjustable morphology is currently a hot area of research in mesoporous materials. Herein, a novel approach is reported for the construction of N-doped multicavity mesoporous carbon nanoparticles (NMMCNs) based on the “emulsion swelling–acid curing mechanism” using a nanoemulsion assembly method under a high-speed shearing force. Intriguingly, this approach adopted a novel acid (HCl) curing procedure. Impressively, the morphology evolution from an internal multicavity to a single cavity and then to a non-cavity interior structure could be accomplished by simply varying the synthesis parameters. Additionally, this synthesis approach ingeniously overcame the following problems: (i) technically, the employment of high temperatures and high pressures in traditional hydrothermal reaction curing environments is avoided; (ii) this approach removes the requirement for silicon coating, which provides a limited pyrolysis condition, to obtain a multi-chamber structure. Resveratrol (Res) is an insoluble natural medicine and was successfully loaded into NMMCNs, thereby the Res–NMMCNs delivery system was constructed. Importantly, the Res–NMMCNs delivery system could still retain the antitumor and antioxidant activity of Res in vitro

Magnetoviscous Property and Hyperthermia Effect of Amorphous Nanoparticle Aqueous Ferrofluids

Abstract Magnetic Fe-B, Fe-Ni-B, and Co-B nanoparticles were successfully synthesized and introduced to water to prepare aqueous ferrofluids. The Fe-B, Fe-Ni-B, and Co-B particles are homogeneous amorphous nanoparticles with an average particle size 15 nm. The shape of the amorphous nanoparticles is regular. The Fe-B, Fe-Ni-B, and Co-B amorphous nanoparticles are superparamagnetic. Moreover, the saturation magnetizations of Fe-B and Fe-Ni-B amorphous nanoparticles are 75 emu/g and 51 emu/g. These are approximately 2.8 and 1.9-fold larger than Co-B nanoparticles, respectively. The viscosity of the amorphous ferrofluids has a strong response to external magnetic field. The yield stress increases with increasing magnetic field. The hyperthermia research of amorphous ferrofluids was firstly investigated. The experimental results indicate that the heating temperature of Fe-B ferrofluid and Fe-Ni-B ferrofluid could increase to 42 °C in 750 s and 960 s, respectively, when the output current is 300 A. The temperature could reach 61.6 °C for a Fe-B ferrofluid. The heating efficiencies of the amorphous ferrofluids demonstrate that the Fe-B ferrofluid and Fe-Ni-B ferrofluid may have great potential for biomedical applications

Power Transfer Efficiency Analysis for Omnidirectional Wireless Power Transfer System Using Three-Phase-Shifted Drive

In order to implement the omnidirectional wireless power transfer (WPT), a novel three-phase-shifted drive omnidirectional WPT system is proposed. This system is comprised of three independent phase-adjusted excitation sources, three orthogonal transmitting coils, and one planar receiving coil. Based on the mutual coupling theory, the power transfer efficiency is derived and the corresponding control mechanism for maximizing this efficiency is presented. This control mechanism only depends on the currents’ root-mean-square (RMS) values of the three transmitting coils and simple calculations after each location and/or posture change of the receiving coil, which provides the real-time possibility to design an omnidirectional WPT system comparing with the other omnidirectional systems. In aid of computer emulation technique, the efficiency characteristic versus the omnidirectional location and posture of the receiving coil is analyzed, and the analytical results verify the validity of the control mechanism. Lastly, a hardware prototype has been set up, and its omnidirectional power transmission capacity has been successfully verified. The experimental results show that the wireless power is omnidirectional and it can be effectively transmitted to a load even though its receiving coil moves and/or rotates in a 3-D energy region

Hollow Nanocages of Ni x Co1−x Se for Efficient Zinc–Air Batteries and Overall Water Splitting

Abstract Developing Earth-abundant, highly efficient, and anti-corrosion electrocatalysts to boost the oxygen evolution reaction (OER), oxygen reduction reaction (ORR), and hydrogen evolution reaction (HER) for the Zn–air battery (ZAB) and for overall water splitting is imperative. In this study, a novel process starting with Cu2O cubes was developed to fabricate hollow Ni x Co1−x Se nanocages as trifunctional electrocatalysts for the OER, ORR, and HER and a reasonable formation mechanism was proposed. The Ni0.2Co0.8Se nanocages exhibited higher OER activity than its counterparts with the low overpotential of 280 mV at 10 mA cm−2. It also outperformed the other samples in the HER test with a low overpotential of 73 mV at 10 mA cm−2. As an air–cathode of a self-assembled rechargeable ZAB, it exhibited good performance, such as an ultralong cycling lifetime of > 50 h, a high round-trip efficiency of 60.86%, and a high power density of 223.5 mW cm−2. For the application in self-made all-solid-state ZAB, it also demonstrated excellent performance with a power density of 41.03 mW cm−2 and an open-circuit voltage of 1.428 V. In addition, Ni0.2Co0.8Se nanocages had superior performance in a practical overall water splitting, in which only 1.592 V was needed to achieve a current density of 10 mA cm−2. These results show that hollow Ni x Co1−x Se nanocages with an optimized Ni-to-Co ratio are a promising cost-effective and high-efficiency electrocatalyst for ZABs and overall water splitting in alkaline solutions

Controlled Growth of N‑Doped and Large Mesoporous Carbon Spheres with Adjustable Litchi-Like Surface and Particle Size as a Giant Guest Molecule Carrier

N-doped mesoporous carbon nanospheres (NMCNs) with tunable particle size, pore size, surface roughness, and inner cavity are extremely important for the future development of new carriers for nanoencapsulation, high-performance giant molecule transport, and cell uptake. However, constructing such a multifunctional material via a simple method still remains a great challenge. Herein, a controlled growth technology was developed for the first time to synthesize such NMCNs based on the initial reaction temperature (IRT) and solution polarity. In this strategy, the IRT not only can adjust the micelle aggregation to obtain NMCNs with large mesopores but also can make the F127 micelle more lyophobic to prepare hollow N-doped mesoporous carbon spheres, which is a great breakthrough. Inspiringly, by varying the solution polarity to make nonuniform growth of nanoparticles, the litchi-like rough surface of NMCNs was obtained, which could significantly improve the cell uptake performance of NMCNs. The current understanding of nucleation and growth mechanism of nanospheres was further extended and realized the development of NMCNs with large mesopores and litchi-like rough surface, which provided a new and interesting fundamental principle for the synthesis of NMCNs. The mesoporous structure of NMCNs was successfully reverse-replicated by nanocasting of tetraethylorthosilicate to obtain mesoporous silica spheres (MSNs), revealing the easy transformation between NMCNs and MSNs. Insulin as a peptide drug cannot be directly administered orally. But it can be used as oral preparation after being loaded into NMCNs, which has never been reported before. Interestingly, the results of the animal experiment showed an excellent in vivo hypoglycemic activity. This finding provides a new paradigm for the fabrication of structurally well-defined NMCNs with a great promise for drug carriers

Rupturing Cotton Microfibers into Mesoporous Nitrogen-Doped Carbon Nanosheets as Metal-Free Catalysts for Efficient Oxygen Electroreduction

Mechanical grinding is exploited to effectively rupture biomass cotton microfibers into metal-free, nitrogen-doped carbon nanosheets with a large number of mesoporous textures. Experimentally, raw microfibers of absorbent cotton are presoaked with fuming sulfuric acid to generate plenty of hierarchical pores/cavities, which sufficiently expose the inner parts of cotton microfibers to nitrogen source for efficient incorporation of nitrogen dopants onto carbon skeletons in subsequent thermal annealing process. Mechanical grinding of these thermally annealed carbon microfibers leads to exfoliated nitrogen-doped thin carbon nanosheets with a high surface area of 912.1 m²/g as well as abundant mesopores and a considerable nitrogen content of 8.5 at. %. These characteristics contribute to an excellent electrocatalyst with marked catalytic activities toward oxygen reduction reaction in an alkaline electrolyte solution, including a more positive half-wave potential, much higher diffusion-limiting current, remarkably enhanced operation stability, and stronger immunity against fuel-crossover effects, as compared to commercial Pt/C catalysts. The present results provide a novel facile method to the scalable preparation of biomass-derived highly porous two-dimensional carbons for efficient electrochemical energy devices