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In recent years, the research of Phenylethynylcopper (PhC2Cu) in the field of photocatalysis has attracted much attention. However, its preparation requires two steps, which take lengthy 9 days. In this paper, A highly rapid and facile one-step method that directly used copper acetate and phenylacetylene as raw materials and ascorbic acid as reducing agent to synthesize PhC2Cu nanowires was successfully developed. The kinetic studies indicated that the synthetic reaction follows a pseudo-second-order equation through electrical conductivity. Comparative studies on the crystal structures, morphologies, optical properties of PhC2Cu prepared by the traditional two-step and this one-step method were conducted by using XRD, SEM, UV–vis Drs, FT-IR, Raman Spectra and Photocurrent. Meanwhile, the PhC2Cu nanowires exhibited excellent photocatalytic activity for the degradation of MV (methyl violet) and glyphosate. Importantly, this facile and rapid method greatly improves the preparation efficiency of PhC2Cu, and the obtained PhC2Cu also shows higher photocatalytic activity. This remarkable progress enables the possibility of large-scale and efficient preparation of PhC2Cu with high photocatalytic activity, indicating their good application prospect in the fields of photocatalysis.

A renewable biomass-based lignin film on Zn anodes was constructed through the robust coordination interaction with Zn2+ and strong adsorption energy with Zn metal to avoid the side reaction with H2O and I3− and restrain the growth of Zn dendrites.

This paper proposes a lossless data hiding scheme in learning with errors (LWE)-encrypted domain based on key-switching technique. Lossless data hiding and extraction could be realized by a third party without knowing the private key for decryption. Key-switching-based least-significant-bit (KSLSB) data hiding method has been designed during the lossless data hiding process. The owner of the plaintext first encrypts the plaintext by using LWE encryption and uploads ciphertext to a (trusted or untrusted) third server. Then the server performs KSLSB to obtain a marked ciphertext. To enable the third party to manage ciphertext flexibly and keep the plaintext secret, the embedded data can be extracted from the marked ciphertext without using the private key of LWE encryption in the proposed scheme. Experimental results demonstrate that data hiding would not compromise the security of LWE encryption, and the embedding rate is 1 bit per bit of plaintext without introducing any loss into the directly decrypted result.

The cladding layer of Ti-6Al-4V alloy was treated by traditional forging and ultrasonic-assisted forging with the self-made forging device. The forged titanium alloy cladding layer was characterize...

Circular RNAs (circRNAs) have been implicated in modulating biological processes in some tumors. However, the contributions and molecular mechanisms of circRNAs to gallbladder cancer (GBC) remain largely unknown. In the present study, our results showed circPVT1 expression was significantly upregulated in GBC tissues and cells. Higher circPVT1 expression was correlated with lymph node metastasis, advanced TNM stage, and poor overall survival (OS) in patients with GBC. Subsequently, knockdown of circPVT1 significantly impeded GBC cell proliferation, migration, invasion, while induced cell apoptosis in vitro. However, upregulated circPVT1 had the opposite effects. In vivo, we also demonstrated that knockdown of circPVT1 inhibited tumor growth. Furthermore, we confirmed that circPVT1 could regulate Myeloid cell leukemia-1 (MCL-1) expression by sponging to miR-339-3p, which affected tumor progression in GBC cells. In summary, our findings indicated that circPVT1 may serve as a promising prognostic marker and therapeutic target for GBC.

Circular RNAs (circRNAs) have been implicated in modulating biological processes in some tumors. However, the contributions and molecular mechanisms of circRNAs to gallbladder cancer (GBC) remain largely unknown. In the present study, our results showed circPVT1 expression was significantly upregulated in GBC tissues and cells. Higher circPVT1 expression was correlated with lymph node metastasis, advanced TNM stage, and poor overall survival (OS) in patients with GBC. Subsequently, knockdown of circPVT1 significantly impeded GBC cell proliferation, migration, invasion, while induced cell apoptosis in vitro. However, upregulated circPVT1 had the opposite effects. In vivo, we also demonstrated that knockdown of circPVT1 inhibited tumor growth. Furthermore, we confirmed that circPVT1 could regulate Myeloid cell leukemia-1 (MCL-1) expression by sponging to miR-339-3p, which affected tumor progression in GBC cells. In summary, our findings indicated that circPVT1 may serve as a promising prognostic marker and therapeutic target for GBC.

The workspace of parallel robot is limited, and the distribution characteristics of kinematics and force maneuverability are complex in the workspace. In addition, there are often operational singularities. The redundant actuation technology can not only overcome singularity problem of force maneuverability of parallel mechanism, but also eliminate the clearance of the mechanism, dynamically adjust the operating stiffness, realize the optimized operation of energy consumption, etc. In this paper, with the goal of realizing dexterous dynamic output control, the variable impedance control technology of redundantly actuated parallel robot based on operation space is studied. Compared with the traditional invariable impedance control, the variable impedance control can adapt to the change of unknown environment by time-varying controlling parameters, which provides the possibility to realize the polishing of complex curved surfaces and thin-walled parts, assembly task and improves the performance of the system and the machining quality of the parts. In order to avoid the influence of unmodeled errors and external interferences on the system, based on the sliding mode control (SMC) strategy, the variable impedance control (VIC) in the operating space of 4RRR redundantly actuated parallel robot (4RAPR) is proposed. The robust stability of the closed-loop system is analyzed and verified by Matlab programming simulation.

This paper proposes a lossless data hiding in encrypted domain (RDH-ED) scheme. To realize the data extraction directly from the encrypted domain without the private key, a key-switching based least-significant-bit (KS-LSB) data hiding method has been designed. In application, the user first encrypts the plaintext and uploads ciphertext to the server. Then the server performs KS-LSB to obtain the marked ciphertext. Additional data can be extracted directly from the marked ciphertext by the server without the private key, which enables the (trusted or untrusted) third party to manage ciphertext flexibly under the premise of keeping the plaintext secret. The Experimental results demonstrate that the embedding capacity is 1bit per bit of plaintext. Data hiding would not affect the accuracy and the security of encryption.

The distortion in steganography that usually comes from the modification or recoding of the cover image during the embedding process. And it is the embedding distortion that leaves the steganalyzer with possible discrimination. Therefore, we propose generative steganography with Kerckhoffs’ principle (GSK) in this paper. In GSK, the secret messages are generated by a cover image using a generator rather than embedded into the cover, which results in no modifications to the cover. To ensure security, the generators are trained to meet Kerckhoffs’ principle based on generative adversarial networks (GANs). Everything about the GSK system is public knowledge for the receivers, except the extraction key. The secret messages can be outputted by the generator if and only if the extraction key and the cover image are both inputted. In the generator training procedures, there are two GANs (Message-GAN and Cover-GAN) that are designed to work jointly, making the generated results under the control of the extraction key and the cover image. We provide experimental results for the training process. We present an example of the working process by adopting a generator trained on the dataset MNIST, which demonstrates that GSK can use a cover image without any modification to generate messages. Furthermore, only meaningless results would be obtained without the extraction key or the cover image.

The effects of SiCp addition on the microstructure and mechanical properties of ZTA ceramics was investigated by microwave sintering. Partially stabilized zirconia（3Y-ZrO2）nanopowder containing SiCp was prepared by microwave pyrolysing precursor which was was achieved by co-precipitation method. The powders of alumina, yttria partially stabilized zirconia containing SiCp were mixed to prepare ZTA ceramics green body by die pressing and cold isostatic pressing and subsequently sintered at the range of 1350°C-1550°C for 30min by microwave. XRD revealed that 3Y-ZrO2/SiC powder contained more tetragonal phase than 3Y-ZrO2 powder which was also confirmed by SEM and particle size distribution. The phenomenon was because of SiCp forming the microwave heating spot that promoted pyrolysis progress when 3Y-ZrO2/SiC powder was prepared by microwave heating. Microstructure showed that the grain of ZTA ceramics had directional growth by microwave sintering. SiCp firstly absorbed microwave that made more uniform sintering of ZTA ceramics and caused local oriented growth of zirconia and alumina. Thus, the bending strength of ZTA ceramics was higher than ZTA without SiCp. The ladder type heating mode of microwave sintering ZTA ceramics reduced relatively sintering time by 20min due to the addition of SiCp.Introduction

This paper proposes a multilevel reversible data hiding scheme in encrypted domain by utilizing the controllable redundancy of learning with error public key cryptography. Messages can be embedded into multilevel sub-regions of ciphertext by quantifying the encrypted domain and recoding its redundancy. We recode redundancy based on the characteristics of cipher’s distribution. Extraction and decryption processes are separated by dividing the encrypted domain into multilevel sub-regions and introducing different quantification standards. Original plaintext can be losslessly recovered from the marked ciphertext by using the decryption key; with a specific level data-hiding key, only the message hiding in the corresponding level can be extracted, while plaintext and other messages remain secret. We provide theoretical analysis and experimental results on the feasibility, reversibility, and security of the proposed scheme. The capacity and encryption blow up factor are discussed. The experimental results demonstrate the maximum embedding rate can exceed 0.3000 bpb of ciphertext.

This paper proposes a fully homomorphic encryption encapsulated difference expansion (FHEE-DE) scheme for reversible data hiding in encrypted domain (RDH-ED). In the proposed scheme, we use key-switching and bootstrapping techniques to control the ciphertext extension and decryption failure. To realize the data extraction directly from the encrypted domain without the private key, a key-switching based least-significant-bit (KS-LSB) data hiding method has been designed. In application, the user first encrypts the plaintext and uploads ciphertext to the server. Then the server performs data hiding by FHEE-DE and KS-LSB to obtain the marked ciphertext. Additional data can be extracted directly from the marked ciphertext by the server without the private key. The user can decrypt the marked ciphertext to obtain the marked plaintext. Then additional data or plaintext can be obtained from the marked plaintext by using the standard DE extraction or recovery. A fidelity constraint of DE is introduced to reduce the distortion of the marked plaintext. FHEE-DE enables the server to implement FHEE-DE recovery or extraction on the marked ciphertext, which returns the ciphertext of original plaintext or additional data to the user. In addition, we simplified the homomorphic operations of the proposed universal FHEE-DE to obtain an efficient version. The Experimental results demonstrate that the embedding capacity, fidelity, and reversibility of the proposed scheme are superior to existing RDH-ED methods, and fully separability is achieved without reducing the security of encryption.

Background: Iron and zinc deficiencies affect human health globally, especially in developing countries. Agronomic biofortification, as a strategy for alleviating these issues, has been focused on small-scale field studies, and not widely applied while lacking of cost-effectiveness analysis (CEA). Objective: We conducted the CEA of agronomic biofortification, expressed as USD per disability-adjusted life years (DALYs) saved, to recommend a cost-effectiveness strategy that can be widely applied. Methods: The DALYs were applied to quantify the health burden due to Fe and/or Zn deficiency and health cost of agronomic biofortification via a single, dual, or triple foliar spray of Fe, Zn, and/or pesticide in 4 (northeast, central China, southeast, and southwest) major Chinese rice-based regions. Results: The current health burden by Fe or Zn malnutrition was 0.45 to 1.45 or 0.14 to 0.84 million DALYs for these 4 regions. Compared to traditional rice diets, the daily Fe and/or Zn intake from Fe and/or Zn-biofortified rice increased, and the health burden of Fe and/or Zn deficiency decreased by 28% and 48%, respectively. The cost of saving 1 DALYs ranged from US$376 to US$4989, US$194 to US$2730, and US$37.6 to US$530.1 for the single, dual, and triple foliar Fe, Zn, and/or pesticide application, respectively, due to a substantial decrease in labor costs by the latter 2 applications. Conclusions: Agronomic biofortification of rice with the triple foliar spray of Fe, Zn, and pesticide is a rapidly effective and cost-effectiveness pathway to alleviate Fe and Zn deficiency for rice-based dietary populations.

By using density functional theory, we studied the interaction process between barbital and 2-vinyl-4,6-diamino-1,3,5-triazine in acetonitrile at 333 K. Barbital and 2-vinyl-4,6-diamino-1,3,5-triazine were used as the template and functional monomer, respectively. The molecularly imprinted polymer microspheres containing barbital and 2-vinyl-4,6-diamino-1,3,5-triazine were synthesized through precipitation polymerization. After removing the template molecule barbital, the average diameter of the obtained molecularly imprinted polymers was 1.45 μm. By optimizing the molar ratio of barbital and the 2-vinyl-4,6-diamino-1,3,5-triazine, the resulting molecularly imprinted polymers showed the highest adsorption for the barbital. The analysis of the Scatchard plot revealed that the dissociation constant (Kd ) and apparent maximum adsorption quantity (Qmax ) of the molecularly imprinted polymers were 30.69 mg/L and 8.68 mg/g, respectively. The study of selective adsorption showed that molecularly imprinted polymers exhibited higher selectivity for barbtital than that for 1,3-dimethyl barbituric acid and pentobarbital. Herein, the studies can provide theoretical and experimental references for the barbital-imprinted system.

Effect of surface preparation on the radiation hardness of MOS devices with high dielectric constant gate dielectric of HfO2 and metal gate of TiN is studied using extreme ultra-violet (EUV) light as the radiation source. Three kinds of surface treatment including HF-last, chemical-oxidation, and rapid-thermal-oxidation were evaluated. Among them, chemical-oxidation exhibits the best radiation hardiness in terms of interface traps and border traps. The state-of-the-art MOSFET with a thin high-k dielectric and a high quality chemical oxide interfacial layer shows that the degradation of subthreshold swing is more severe than degradation of threshold voltage. However, the overall degradation is less than 6% even after EUV irradiation to a total dose of 580 mJ/cm2. Off-state current degradation is observed due to the generation of oxide traps and interface traps at the isolation region. This phenomenon does not occur in the conventional optical lithography process but should be considered if EUV lithography is used.

In order to improve the positioning accuracy and reduce the localization cost, a kind of PSO-based RFID indoor localization algorithm is proposed in this paper. The main idea of this algorithm contains the following two aspects. First, due to the influence of none line of sight and multipath transmission in indoor environment, we adopt Gaussian Smoothing Filter to process Received Signal Strength Indicator (RSSI) values, which can reduce the impact of environmental factors on the position estimation effectively. Second, Particle of Swarm Optimization (PSO) algorithm is introduced to obtain a better positioning result. By experimenting in different indoor environment, the results demonstrate that the proposed approach can not only improve the precision of indoor localization, but has a lower cost and better robustness when compared to VIRE approach.

K0.5Na0.5NbO3 powders have been directly synthesized by an alternative solid–state method. Stoichimometric mixture of ammonium niobium oxalate and C4H4O6KNa·4H2O were calcined in temperature range from 500 to 800 °C for 3 h. The precursor and calcination products were characterized with respect to stoichiometry, purity, crystalline structure, particle size and powder morphology using X–ray diffraction (XRD), X-ray fluorescence (XRF) spectrometer, scanning electron microscope (SEM), Fourier transform infrared (FTIR) spectra, thermogravimetric (TG) analysis, differential scanning calorimetry (DSC) and UV–Vis diffuse reflectance (UV–Vis) spectroscopy. XRD and XRF results reveal that stoichiometric K0.5Na0.5NbO3 powders could be synthesized by the method. The particle size is about 68 nm for the precursor calcined at 500 °C according to XRD data, which is in good agreement with SEM data. The average band gap energy is estimated to be 3.18 eV by UV–vis diffuse reflectance spectra. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

A facile route to prepare lithium niobate (LiNbO3) powders was proposed by an alternative solid-state method. Stoichiometric Li2C2O4 and ammonium niobium oxalate were mixed with small amounts of water and then dried at room temperature. It was demonstrated that Li[NbO(C2O4)2]·n H2O intermediate was produced by an ion-exchange reaction. Pure LiNbO3 powders were successfully synthesized by heating the intermediate at 500, 600 and 700 °C for 3 h. X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy, UV-Vis diffuse reflectance (UV-Vis) spectroscopy and thermogravimetric (TG) analysis were used to characterize the precursor compound and as-prepared samples. XRD results reveal that all the products are identified as hexagonal structure with high relative crystallinity (>87%). The particle size is found to be about 40 nm for the mixture calcined at 500 °C according to XRD data, which is in good agreement with SEM data. The as-prepared LiNbO3 powders by this method are high quality according to FTIR spectra. (Li0.996Nb0.005)Nb0.999O3 phase was formed when the calcination temperature was raised to 800 °C. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

By using density functional theory, we studied the interaction process between barbital and 2-vinyl-4,6-diamino-1,3,5-triazine in acetonitrile at 333 K. Barbital and 2-vinyl-4,6-diamino-1,3,5-triazine were used as the template and functional monomer, respectively. The molecularly imprinted polymer microspheres containing barbital and 2-vinyl-4,6-diamino-1,3,5-triazine were synthesized through precipitation polymerization. After removing the template molecule barbital, the average diameter of the obtained molecularly imprinted polymers was 1.45 μm. By optimizing the molar ratio of barbital and the 2-vinyl-4,6-diamino-1,3,5-triazine, the resulting molecularly imprinted polymers showed the highest adsorption for the barbital. The analysis of the Scatchard plot revealed that the dissociation constant (Kd ) and apparent maximum adsorption quantity (Qmax ) of the molecularly imprinted polymers were 30.69 mg/L and 8.68 mg/g, respectively. The study of selective adsorption showed that molecularly imprinted polymers exhibited higher selectivity for barbtital than that for 1,3-dimethyl barbituric acid and pentobarbital. Herein, the studies can provide theoretical and experimental references for the barbital-imprinted system.

In the face of escalating problems with pathogen control, the development of proper formulations of existing antibiotics is as important as the development of novel antibiotics. Daptomycin is a lipopeptide antibiotic with potent activity against Gram-positive bacteria. Currently, only injectable solution of daptomycin has been approved for clinical use. In the present study, the formulation of PEGylated liposomal daptomycin (PLD) was prepared and optimized, and its efficacy against methicillin-resistant Staphylococcus aureus (MRSA252) strains was investigated. The obtained PLD had a mean vesicle diameter of (111.5 +/- 15.4) nm and a mean percent drug loading of (5.81 +/- 0.19) % with high storage stability. Potent activity of PLD against MRSA was demonstrated in vitro with a more sustained effect than that of conventional liposomal daptomycin and daptomycin solution. In addition, intravenous administration of a single dose (equal to human use) of PLD significantly increased the survival of mice in a MRSA252 systemic infection model compared with other formulations. Drug distribution in the lung was significantly enhanced following administration of PLD, and no measurable tissue lesions or pathological changes were detected during PLD treatment. Taken together, PEGylated liposomes loaded with daptomycin may represent a promising approach to reduce MRSA252 infections, especially those involving bloodstream dissemination, such as hematogenous pulmonary infection.

In this study, we developed a novel liposome-silica hybrid nano-carrier for tumor combination therapy via oral route, using paclitaxel and cyclosporine as a model drug pair. Optimization of the preparation of the drug-loading formulation and characterization of its physicochemical parameters and drug release profile were performed in vitro. Then in vivo pharmacodynamics and pharmacokinetics studies were performed. The results showed that the obtained formulation has a small particle size (mean diameter of 100.2 +/- 15.2 nm), a homogeneous distribution [the polydispersity index was (0.251 +/- 0.018)] and high encapsulation efficiency (90.15 +/- 2.47) % and (80.64 +/- 3.52) % for paclitaxel and cyclosporine respectively with a mild and easy preparation process. A sequential drug release trend of cyclosporine prior to palictaxel was observed. The liposome-silica hybrid nano-carrier showed good biocompatibility in vivo and co-delivery of cyclosporine and paclitaxel significantly enhanced the oral absorption of paclitaxel with improved anti-tumor efficacy, suggesting a promising approach for multi-drug therapy against tumor and other serious diseases via oral route.

The aim of this study is to investigate the feasibility of silica-coated ethosome as a novel oral delivery system for the poorly water-soluble curcumin (as a model drug). The silica-coated ethosomes loading curcumin (CU-SE) were prepared by alcohol injection method with homogenization, followed by the precipitation of silica by sol-gel process. The physical and chemical features of CU-SEs, and curcumin release were determined in vitro. The pharmacodynamics and bioavailability measurements were sequentially performed. The mean diameter of CU-SE was (478.5 +/- 80.3) nm and the polydispersity index was 0.285 +/- 0.042, while the mean value of apparent drug entrapment efficiency was 80.77%. In vitro assays demonstrated that CU-SEs were significantly stable with improved release properties when compared with curcumin-loaded ethosomes (CU-ETs) without silica-coatings. The bioavailability of CU-SEs and CU-ETs was 11.86- and 5.25-fold higher, respectively, than that of curcumin suspensions (CU-SUs) in in vivo assays. The silica coatings significantly promoted the stability of ethosomes and CU-SEs exhibited 2.26-fold increase in bioavailablity relative to CU-ETs, indicating that the silica-coated ethosomes might be a potential approach for oral delivery of poorly water-soluble drugs especially the active ingredients of traditional Chinese medicine with improved bioavailability.

Powders of the title compound are prepared by solid state reaction of stoichiometric mixtures of NH4 [NbO(C2O4)2(H2O)2] (H2O)3 and sodium potassium tartrate (500—800 °C, 3 h).