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Bistatic scattering coefficient have important application of ocean active microwave remote sensing. In this paper, a general expression of the composite scattering coefficient for multiple dielectric targets of one-dimensional fractal sea surface is derived by MOM method. Secondly, the bistatic scattering coefficient is computed, there are two class missile targets and one class ship target of one-dimensional fractal sea surface, and the influence of the water dielectric constant, fractal dimension, wind speed, the target dielectric constant and spatial position is discussed, and the corresponding conclusions are given. The proposed algorithm is able to solve some composite scattering problems, such as 'dielectric or conductive object + rough surface', 'dielectric or conductive floating object +rough' and it has certain generalization and reference, and it lays a foundation for solving the composite scattering coefficient of multiple medium targets in two-dimensional fractal sea surface. [ABSTRACT FROM AUTHOR]

In order to study the influence of web holes on axial compression behaviors of thin-walled columns with different section forms, a total of 10 pin-ended compression specimens with two section forms were tested. One section is channels with complex edge stiffeners and web holes, the other section is channels with complex edge stiffeners and Σ type web stiffeners and web holes. The ultimate load, buckling mode and deformation behavior of these specimens were studied. It was found that the axial compression loading efficiency of perforated Σ-section specimens can increase about 30% to 50%, which compared with channels with complex edge stiffeners and web holes under the same conditions. The tests were simulated by finite element analysis (FEA), and the analysis results agreed well with experimental data. It was shown that the loading efficiency of Σ-section models with holes decreased about 25% compared with the same section models without holes. While channel section models with complex edge stiffeners and holes decreased about 6% average. Furthermore, the direct strength method (DSM) was used to calculate the ultimate loading capacity of perforated channels with complex edge stiffeners. The results indicate that the existing DSM formulas for perforated members, developed mainly based on channel sections with simple edge stiffeners, are also valid for channels with complex edge stiffeners and web holes under axial compression. [ABSTRACT FROM AUTHOR]

A method based on use of functionalized gold nanoparticles on polyethylenimine film has been developed for colorimetric detection of immunoglobulin G (IgG). The immunogold nanoparticles were immobilized on quartz slides by recognition between antibody and antigen, with the antigen chemically adsorbed on the polyethylenimine film. By measurement of the UV–visible spectra of the immobilized immunogold, detection of h-IgG was achieved. The detection limit for h-IgG by use of this method can be as low as 0.01 μg mL−1. This method is quite promising for numerous applications in immunoassay. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A simple, cost-effective yet rapid and sensitive colorimetric sensor for the detection of Hg2+ using L-cysteine functionalized gold nanoparticles induced by ultraviolet radiation was developed. The sensitivity and selectivity of detection was also investigated. The L-cysteine modified gold nanoparticles can be induced to aggregate quickly in the presence of Hg2+, especially with the assistance of ultraviolet radiation. The presence of Hg2+ can be monitored by the colorimetric response of gold nanoparticles. The detection of Hg2+ could be realized, after measuring the UV-vis spectra, with a detection limit of 100 nM. The selectivity of this method has been investigated by other divalent metal ions. The effective colorimetric sensor can be used for on-site and real-time Hg2+ detection. [ABSTRACT FROM AUTHOR]

A one-step rapid and ultrasensitive immunoassay capable of detecting proteins in blood serum is developed using gold nanoprobes and fluorescence correlation spectroscopy (FCS). In this approach we take advantage of the inherent photoluminescence property of gold nanoparticles (GNPs) to develop a fluorophore-free assay to observe binding entities by monitoring the diffusion of bound versus unbound molecules in a limited confocal volume. 40-nmGNPs conjugated separately with rabbit anti-IgG (Fc) and goat anti-IgG (Fab) when incubated in blood serum containing IgG forms a sandwich structure constituting dimers and oligomers that can be differentiated by to detect IgG in blood serum at a limit of detection (LOD) of 5 pgml. The novelty of integrating GNPs with FCS to develop a sensitive blood immunoassay brings single molecule methods one step closer to the clinic. [ABSTRACT FROM AUTHOR]

This paper reports for the first time that the shape of silver nanostructures on quartz slides, from a nanoprism to a nanodisc, can be easily realized within a few minutes simply by adjusting the pH value of the immersion solution. Different colours of the quartz slide covered with Ag nanostructures appeared, from deep blue to yellow, corresponding to the shapes of Ag nanostructures changing from nanoprisms to nanodiscs. Surface-enhanced Raman scattering (SERS) activities of the silver nanoprisms and nanodiscs (obtained through adjusting the pH values) were checked using p-aminothiophenol (p-ATP) as a probe molecule at both near-infrared (1064 nm) and visible light (514.5 nm) excitation. The results obtained further confirmed the enhancement mechanism of SERS based on the coupling between the surface plasmon resonance (SPR) of the substrates and the laser excitation wavelength. This work will be of great significance in understanding the SERS enhancement mechanism and in the fabrication of nanoparticle films for biosensing. [ABSTRACT FROM AUTHOR]

Multifunctional nanoparticles (NPs) simultaneously having functions of multimodal therapy and imaging are highly needed in biomedical applications. A unique monstera flower-like gold nanorod/polydopamine bowl (GNR/PDA bowl) with spadix-bract nanostructure was fabricated by a novel and facile approach. The possible formation mechanism of the GNR/PDA bowl spadix-bract NPs was proposed by monitoring the synthetic process. The obtained monstera flower-like GNR/PDA bowl spadix-bract NPs were further selectively functionalized with 1-dodecanethiol (DT) on GNR domains (spadix) to achieve efficient hydrophobic drug delivery capability; meanwhile, the PDA bowl (bract) can load the hydrophilic anticancer drug doxorubicin (DOX). The resultant monstera flower-like DT-GNR/PDA bowl spadix-bract NPs possess an excellent biocompatibility, high dual-drug-loading contents, excellent photothermal conversion efficiency, strong near-infrared (NIR) absorbance, effective attenuation of X-rays, and pH/NIR dual-responsive properties, which enable the NPs to be applied for synergistic bimodal computed tomography/photoacoustic (CT/PA) imaging-guided multidrug chemotherapy and photothermal therapy (PTT). Moreover, the synthetic approach could be extended to prepare Au/PDA bowl NPs and Fe2O3/PDA bowl NPs, which may greatly expand the application of the PDA-based bowl NPs. [ABSTRACT FROM AUTHOR]

A facile strategy to fabricate gold nanorod@polyacrylic acid/calcium phosphate (AuNR@- PAA/CaP) yolk-shell nanoparticles (NPs) composed with a PAA/CaP shell and an AuNR yolk is reported. The asobtained AuNR@PAA/CaP yolk-shell NPs possess ultrahigh doxorubicin (DOX) loading capability (1 mg DOX/mg NPs), superior photothermal conversion property (26%) and pH/near-infrared (NIR) dual-responsive drug delivery performance. The released DOX continuously increased due to the damage of the CaP shell at low pH values. When the DOX-loaded AuNR@PAA/CaP yolk-shell NPs were exposed to NIR irradiation, a burst-like drug release occurs owing to the heat produced by the AuNRs. Furthermore, AuNR@PAA/CaP yolk-shell NPs are successfully employed for synergic dual-mode X-ray computed tomography/photoacoustic imaging and chemo-photothermal cancer therapy. Therefore, this work brings new insights for the synthesis of multifunctional nanomaterials and extends theranostic applications. [ABSTRACT FROM AUTHOR]

Objective: To investigate the stroke risk and risk factors in patients with chronic schizophrenia. Patients and methods: This study was a large-sample, cross-sectional survey. A total of 363 patients with chronic schizophrenia were selected from the Changping Traditional Chinese Medicine Hospital, Beijing, in August 2014. The patients were divided into either stroke group or control group based on the presence of stroke. Clinical evaluation included positive and negative syndrome scale assessment and a detailed questionnaire to collect the general information and disease-related conditions. Results: The prevalence of stroke was 16.5% (60 cases). Stroke and control groups showed a significant difference in age, sex, smoking, combined medication, doses, negative factor score in positive and negative syndrome scale, body mass index, waist circumference, and systolic blood pressure. Multivariate analysis showed that a number of factors are significantly related to stroke, including age, sex, smoking, combined medication, doses, body mass index, and systolic blood pressure. Conclusion: The prevalence of stroke is relatively higher in Chinese patients with chronic schizophrenia. Chronic schizophrenia patients are more likely to suffer from stroke; meanwhile, a number of risk factors were identified, including old age, female sex, smoking history, combined medication with a variety of drugs, high doses, obesity, and high blood pressure. [ABSTRACT FROM AUTHOR]

A facile two-step strategy was developed to fabricate yellow fluorescent glutathione-Au nanoclusters/zeolitic imidazolate framework-8 nanoparticles (GSH-Au NCs/ZIF-8 NPs) and their derived Au/ZnO NPs, which exhibited visible light photocatalytic hydrogen evolution together with degradation of Rhodamine B (RhB). [ABSTRACT FROM AUTHOR]

A universal method was utilized to fabricate rhombic dodecahedral zeolitic imidazolate framework-8@SiO2 (ZIF-8@SiO2) nanoparticles (NPs) and their derivatives, ZnO@SiO2, ZIF-8@SiO2 yolk--shell and SiO2 hollow NPs, using ZIF-8 NPs as the template. [ABSTRACT FROM AUTHOR]

Rapid and sensitive detection of 2,4,6-trinitrotoluene (TNT) and 4-nitrophenol (4-NP) has attracted considerable attention due to their wide applications as nitroaromatic explosive materials. A novel fluorescence method for TNT and 4-NP based on bovine serum albumin functionalized fluorescent gold nanoclusters (BSA Au-NCs) has been developed. The detection probe BSA Au-NCs can be used as a fluorescent probe for the sensitive and selective detection of TNT and 4-NP simultaneously. A good linearity of fluorescence detection using BSA Au-NCs as a fluorescent probe was observed for TNT and 4-NP concentrations in the range of 10-8-5 × 10-5 M and 10-9-5 × 10-5 M, with a detection limit of 10 nM and 1 nM, respectively. The high specificity of TNT and 4-NP with BSA Au-NCs interactions provided excellent selectivity towards detecting TNT and 4-NP over other relevant nitroaromatic compounds. This system can be applied to test strips to detect TNT and 4-NP with high sensitivity and selectivity. The vapour of TNT and 4-NP can be detected using BSA Au-NCs test paper within 1 min with a detection limit of 10 pM and 1 pM. [ABSTRACT FROM AUTHOR]

The article discusses the facile two-step approach for the fabrication of green fluorescent carbon nanodots@zeolitic imidazolate framework-8 nanoparticles (C-dots@ZIF-8 NP) with tunable size and fluorescence intensity. The nanoparticles serve as platforms for simultaneous pH-responsive drug delivery and fluorescence imaging for cancer cells. It also compares the c-dots against toxic metal-based quantum dots (QD).