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Hinged arrays have garnered increasing interest due to their potential to provide flexible and adaptable solutions for the various challenges faced in ocean development. The effectiveness of these arrays in engineering applications heavily depends on the motion characteristics of each individual module, rather than specific modules, such as the one with the strongest motion. However, the presence of hinge constraints results in coupled motion responses of all modules instead of independent ones. The objective of this study is to investigate the motion behavior of large arrays formed by multiple floaters hinged together, while existing literature mainly focused on two-body hinged systems. Based on the potential flow theory and Rankine source panel method, a numerical program was developed to calculate the hydrodynamic interactions and the coupled motion responses. First, a model test was conducted to validate the developed frequency-domain simulations. A good agreement was achieved. Then, the effects of hinge constraints, the number of modules, and two external constraints on the motion responses of the entire array were discussed. The results indicated that the heave motion of the array subjected to hinge constraints was significantly suppressed, but a strong pitch motion occurred in a larger wavelength range. For hinged arrays, the floaters located at the two ends were most likely to be excited with the strongest motions. Moreover, a shorter hinged array could be used to quantify the trends in the motion of arrays with more floaters. The calculation results also revealed that the motion responses of a hinged array were highly sensitive to the external constraints, e.g., mooring lines. [ABSTRACT FROM AUTHOR]

Since light propagation in water bodies is subject to absorption and scattering effects, underwater images using only conventional intensity cameras will suffer from low brightness, blurred images, and loss of details. In this paper, a deep fusion network is applied to underwater polarization images; that is, the underwater polarization images are fused with intensity images using the deep learning method. To construct a training dataset, we establish an experimental setup to obtain underwater polarization images and perform appropriate transformations to expand the dataset. Next, an end-to-end learning framework based on unsupervised learning and guided by an attention mechanism is constructed for fusing polarization and light intensity images. The loss function and weight parameters are elaborated. The produced dataset is used to train the network under different loss weight parameters, and the fused images are evaluated based on different image evaluation metrics. The results show that the fused underwater images are more detailed. Compared with light intensity images, the information entropy and standard deviation of the proposed method increase by 24.48% and 139%. The image processing results are better than other fusion-based methods. In addition, the improved U-net network structure is used to extract features for image segmentation. The results show that the target segmentation based on the proposed method is feasible under turbid water. The proposed method does not require manual adjustment of weight parameters, has faster operation speed, and has strong robustness and self-adaptability, which is important for research in vision fields, such as ocean detection and underwater target recognition. [ABSTRACT FROM AUTHOR]

Large-scale floating photovoltaics (FPV) are garnering increased attention as a sustainable solution for renewable energy production and efficient utilization of ocean spaces. These FPV arrays are predominantly deployed in shallow water environments, which present significant challenges in mooring system design due to substantial tidal fluctuations. In such settings, mooring systems may become slack and lose functionality at low tide or risk damage from excessive stiffness at high tide. The primary aim of this study is to develop a mooring system tailored to FPV arrays, capable of withstanding extensive tidal variations without causing damage to the floating modules due to high mooring line tension. Employing HydroD, a hydrodynamic analysis tool based on potential flow theory, alongside OrcaFlex, a time-domain coupled analysis tool predicated on the lumped mass method, we conducted a comparative assessment of six distinct mooring configurations. These configurations, varying in mooring line materials and components, were evaluated from static, dynamic, and fatigue analysis standpoints across a range of tidal levels. The results indicate that taut mooring systems integrated with buoys or clumps consistently exhibit superior performance in all test scenarios. Accordingly, these systems are highly recommended for securing FPV arrays in shallow water environments characterized by severe tidal variations, offering optimal stability and resilience. • Challenges in designing mooring systems for FPV arrays in shallow waters with significant tidal varations are concluded. • Six distinct mooring configurations consisting of various materials and componets are meticulously designed and compared. • Taut mooring concepts integrated buoys or clumps are recommended for securing FPV arrays in shallow water environments. [ABSTRACT FROM AUTHOR]

Electromagnetic (EM) wave absorbing materials have been a research hotspot in materials science and related technical fields in recent years. Finding lightweight, efficient, and broadband electromagnetic wave absorbing materials has always been a very challenging subject. Herein, we successfully prepared Co3O4-WS2 hybrid nanosheets with heterostructures, which excellent combine the advantages of magnetic property of Co3O4 and dielectric property of WS2. By the electromagnetic synergy effect, maximum RL is up to −61.1 dB at 1.9 mm, and the bandwidth exceeds 5 GHz. Such highly efficient microwave absorption is attributed to not only the electromagnetic synergy effect, but the dipole polarization as well as conduction loss. These results show that the obtained Co3O4-WS2 is an excellent EM wave absorbing material and can be used as a candidate for advanced EM wave absorbing materials in the fields such as commerce, military and aerospace in future. [ABSTRACT FROM AUTHOR]

Electromagnetic (EM) wave absorbing materials have been a research hotspot in materials science and related technical fields in recent years. Finding lightweight, efficient, and broadband electromagnetic wave absorbing materials has always been a very challenging subject. Herein, we successfully prepared Co3O4-WS2 hybrid nanosheets with heterostructures, which excellent combine the advantages of magnetic property of Co3O4 and dielectric property of WS2. By the electromagnetic synergy effect, maximum RL is up to −61.1 dB at 1.9 mm, and the bandwidth exceeds 5 GHz. Such highly efficient microwave absorption is attributed to not only the electromagnetic synergy effect, but the dipole polarization as well as conduction loss. These results show that the obtained Co3O4-WS2 is an excellent EM wave absorbing material and can be used as a candidate for advanced EM wave absorbing materials in the fields such as commerce, military and aerospace in future. [ABSTRACT FROM AUTHOR]

WS 2 nanomaterials have attracted great attention in the field of electromagnetic wave absorption due to their high specific surface area, layered structure, and peculiar electronic properties. However, further improvements on their limited electromagnetic absorbing (EMA) capacity and bandwidth are urgently required for their practical application as EMA absorbents. In this work, WS 2 /NiO hybrids with heterostructures are prepared by a hydrothermal method and developed into EMA absorbents. The maximum reflection loss of the hybrids with 20% NiO loading could reach −53.31 dB at a thickness of 4.30 mm; the bandwidth with a reflection loss value of less than −10 dB is determined to be 13.46 GHz (4.54–18 GHz) when the thickness of the absorbent is between 3.5 and 5.5 mm. It is found that the enhanced EMA performance of WS 2 /NiO hybrids is caused by the addition of magnetic NiO, which could result in the interfaces between WS 2 and NiO being responsible for the synergetic magnetic loss and dielectric loss in the hybrids. This work provides a new approach for the design of excellent EMA materials for practical applications. [ABSTRACT FROM AUTHOR]

Direct and label‐free detection of unmodified DNA has always been a great challenge for DNA analyses. Surface‐enhanced Raman spectroscopy (SERS) can provide structural fingerprinting of analytes with single‐molecules sensitivity, so it could be the best candidate for label‐free detection of DNA. Wild mushrooms, a very nutritious and delicious food in our lives, are widely distributed in Yunnan province. Herein, a simple and reliable method, based on SERS, was developed for label‐free detection of DNA from six wild mushrooms and three common edible mushrooms. Concentrated Ag colloid prepared by microwave heating method with high SERS activity was used to obtain high reproducible SERS spectra. SERS signatures and spectroscopic band assignments of these mushrooms DNA were analyzed. Principal component analysis was used to distinguish these nine mushrooms. This experiment provides a simple and reliable method to detect mushrooms DNA, which is useful for the study of mushrooms DNA. Also, this approach has great potential for species identification of wild mushrooms and provides a basis for learning the interaction between DNA and small molecules. To our best knowledge, it is the first SERS study on DNA from wild mushrooms. [ABSTRACT FROM AUTHOR]

In this study, MoS 2 nanosheets were prepared using a facile hydrothermal method and we studied their electromagnetic wave shielding performance for the first time. The results showed that the nanosheets synthesized with a reaction time of 10 h exhibited excellent electromagnetic shielding performance and the attenuation of electromagnetic waves was greater than 20 dB in the frequency range from 2 to 18 GHz. These findings may facilitate the development of novel layered nanomaterials with excellent electromagnetic shielding properties. • Molybdenum disulfide nanosheets with shielding properties are prepared. • Raman shifts of E 2g and A 1g peaks were 376.03 cm−1 and 402.32 cm−1. • MoS 2 nanosheets were ultra-thin with less than four layers. • Absorption loss was the main attenuation mechanism. [ABSTRACT FROM AUTHOR]

In this study, we report two-dimensional WS2 nanosheets successfully synthesized by simple hydrothermal method. The obtained WS2 nanosheets are very promising as electromagnetic wave absorbers. The phase composition, microstructure, electromagnetic properties and microwave absorption properties of the prepared WS2 nanosheets were characterized by XRD, SEM, TEM, XPS and vector network analyzers. Our results show that the real and imaginary parts of permittivity of WS2 prepared at 210 °C are higher than those of other samples, with maximum interfacial polarization and dielectric loss, a wide effective absorption band with a thinner thickness is obtained in the frequency range of 5.5–18 GHz. The effective absorption bandwidth can reach 12.5 GHz, the highest reflection loss of the sample wax containing 40% WS2 is –15.6 dB at a thickness of 5.5 mm, and the absolute value of RL is greater than 10 dB in the range of 2.0–5.5 mm. The results show that the prepared WS2 nanosheets have the advantages of wide bandwidth, strong absorption and light weight, and have potential application prospects in the application and development of microwave absorbing materials in the future. [ABSTRACT FROM AUTHOR]

The hydrothermal method was utilized to synthesize flat sheet-like tungsten disulfide with a single-crystal structure, using sodium diethyldithiocarbamate, tungsten hexachloride and cetyltrimethylammonium bromide as a reducing agent and a sulfur source, a tungsten source and a surfactant, respectively. The controllable synthesis of the tungsten disulfide nanosheet was realized by controlling the types of surfactants, which was characterized by XRD, FTIR, XPS, SEM, TEM, HRTEM, BET, UV-vis and PL. Due to the unique flat sheet morphology and unique electronic characteristic of the synthesized tungsten disulfide nanosheets, they could be promising nanomaterials for electronic devices. [ABSTRACT FROM AUTHOR]

Autophagy is a dynamic recycling process that eliminates damaged proteins and cellular organelles to maintain cellular homeostasis. Aldose reductase (AR) catalyzes conversion of glucose to sorbitol. It also catalyzes the reduction of a broad array of saturated and unsaturated aldehydes. Recently we demonstrated that deletion of AR promotes pathological cardiac remodeling via excessive autophagy; however, the role of AR in starvation-induced autophagy has not been determined. To determine the role of AR in starvation-induced autophagy, WTC57/Bl6 mice were pretreated with the AR inhibitor sorbinil (0.2 g/L for 48 h) in drinking water, followed by 24 h fasting. We found that the sorbinil pretreatment in fed mice did not affect blood glucose levels, whereas, it decreased the blood glucose levels in fasting mice. In comparison with fed mice, the LC3II formation and LCII/LCI ratio were increased in the fasted mice hearts and sorbinil pretreatment further enhanced LC3II formation and LC3II/LC3I ratios in these hearts. Fasting-induced autophagy coincided with AMPK activation in the sorbinil pretreated fasted mice hearts. Autophagy and activation of AMPK was also induced in the gastrocnemius skeletal muscle of sorbinil pre-treated fasted mice. Induction of autophagy in the cardiac tissues of sorbinil pretreated fasted mice was accompanied by increased clearance of 4-hydroxy trans -2-nonenal-protein adducts. Taken together, these results indicate that the inhibition of AR during fasting activates autophagic response, increases clearance of aldehyde-protein adducts, which could serve as a mechanism to maintain cellular homeostasis during starvation. • Aldose reductase (AR) inhibition enhances starvation induced autophagy in heart and skeletal muscle. • Degradation of aldehyde modified protein adducts is enhanced by AR inhibition during starvation. • Inhibition of AR during insulin resistant states could provide energy by enhancing autophagic flux. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The MoS 2 /RGO and MoS 2 /Fe 3 O 4 hybrids are prepared by a facile synthesis route. • The MoS 2 /RGO and MoS 2 /Fe 3 O 4 hybrids with hetero-structures exhibit excellent microwave absorption properties. • Tailoring weight percentage and thickness tunes microwave absorption for high efficiency and broad bandwidth. • The mechanisms of high-performance microwave absorption of MoS 2 /RGO and MoS 2 /Fe 3 O 4 hybrids are elucidated. Abstract The two-dimensional (2D) transition metal dichalcogenide, molybdenum disulfide (MoS 2), has been demonstrated to be a new class of microwave absorption (MA) material due to its high specific surface area and peculiar electronic properties. However, its limited MA capacity and bandwidth require further improvement. MoS 2 /RGO composites with improved MA performance have been reported, but the complicated and inefficient preparation process also limits the application of MoS 2 /RGO composites. In this work, we prepare MoS 2 /RGO hetero-structure hybrid with excellent MA performance and broadened bandwidth by a facile one-step hydrothermal method. It is found that the highest reflection loss value of the sample-wax containing 40% MoS 2 /RGO is −49.41 dB at a thickness of 2.52 mm, and the bandwidth of RL values less than −10 dB can reach up to 13.36 GHz (from 4.64 to 18 GHz). Meanwhile, we investigate another strategy to prepare MoS 2 /Fe 3 O 4 hybrid with hetero-structures and their MA performance is studied for the first time. It is found that the highest reflection loss value of sample-wax containing 40% MoS 2 /Fe 3 O 4 is −42.57 dB at a thickness of 3.25 mm, and the bandwidth of RL values less than −10 dB can reach up to 12.73 GHz (from 5.27 to 18 GHz). Results obtained in this study open a new window for designing excellent MA materials for practical applications. [ABSTRACT FROM AUTHOR]

Modularized floating solar farms exhibit the potential to replace conventional steel-frame ones, effectively remedying hydroelastic issues of a very large floating structure through discrete modules with mechanical connections. However, the response of the discrete modules under cyclic wave loading has not been fully understood. This paper assesses the motion characteristics and expansibility of modularized floaters in waves, based on computational results from fluid–structural interaction simulations. A crucial factor, denoted as the ratio of frame length to wavelength R = L s / λ , is determined to predict the motions of a large floating solar system in head waves. Results indicate that the motion characteristics is predictable based on the R value. The empirical relationship between the R value and the motion of every unit in an array is analyzed. In particular, the results calculated from using the multiple-rigid-bodies method are also compared with those from using the single-large-hydroelastic-body method, and it was found that these two results are similar when R > 1. This similarity allows for predicting the multi-hinged bodies' behavior in waves through a simplified hydroelastic approach. Overall, this study reports insights that are useful for the design and optimization of modularized solar farms and can help address cyclic loading and motion concerns for long-term durability. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) nanomaterials have become a new class of microwave absorption (MA) materials due to their high specific surface area and peculiar electronic properties. In this study, MoS 2 /graphene 2D hybrid nanosheets with isomorphic hetero-structures are prepared by liquid exfoliation and hydrothermal reaction. Their chemical composition and morphology are characterized and their MA properties are also investigated comprehensively. The minimum reflection loss (RL) value of an absorber containing wax and 20 wt% MoS 2 /graphene hybrid nanosheets (MoS 2 /GN) is −55.3 dB at a thickness of only 1.6 mm. The largest effective absorption bandwidth is up to 5.6 GHz for an absorber containing wax and 15 wt% MoS 2 /GN at a thickness of 2.2 mm. The enhanced MA performance of MoS 2 /GN is attributed to the high electrical conductivity of graphene and the multiple MoS 2 /graphene interfaces in the heterogeneous structures. The results suggest that those light-weight MoS 2 /graphene hybrid nanosheets are very promising materials for electromagnetic wave absorbing, which can exhibit broad effective absorption bandwidth in the absorber containing low loadings of MA materials at a small thickness. Besides, the facile preparation of MoS 2 /graphene hybrid nanosheets reported in this work provides a feasible and effective approach in the synthesis of high-performance 2D MA nanomaterials. [ABSTRACT FROM AUTHOR]

Pathological cardiac hypertrophy is associated with the accumulation of lipid peroxidation-derived aldehydes such as 4-hydroxy- trans -2-nonenal (HNE) and acrolein in the heart. These aldehydes are metabolized via several pathways, of which aldose reductase (AR) represents a broad-specificity route for their elimination. We tested the hypothesis that by preventing aldehyde removal, AR deficiency accentuates the pathological effects of transverse aortic constriction (TAC). We found that the levels of AR in the heart were increased in mice subjected to TAC for 2 weeks. In comparison with wild-type (WT), AR-null mice showed lower ejection fraction, which was exacerbated 2 weeks after TAC. Levels of atrial natriuretic peptide and myosin heavy chain were higher in AR-null than in WT TAC hearts. Deficiency of AR decreased urinary levels of the acrolein metabolite, 3-hydroxypropylmercapturic acid. Deletion of AR did not affect the levels of the other aldehyde-metabolizing enzyme - aldehyde dehydrogenase 2 in the heart, or its urinary product - ( N -Acetyl-S-(2-carboxyethyl)- l -cystiene). AR-null hearts subjected to TAC showed increased accumulation of HNE- and acrolein-modified proteins, as well as increased AMPK phosphorylation and autophagy. Superfusion with HNE led to a greater increase in p62, LC3II formation, and GFP-LC3-II punctae formation in AR-null than WT cardiac myocytes. Pharmacological inactivation of JNK decreased HNE-induced autophagy in AR-null cardiac myocytes. Collectively, these results suggest that during hypertrophy the accumulation of lipid peroxidation derived aldehydes promotes pathological remodeling via excessive autophagy, and that metabolic detoxification of these aldehydes by AR may be essential for maintaining cardiac function during early stages of pressure overload. [ABSTRACT FROM AUTHOR]

Multiferroics have broad application prospects in various fields such as multi-layer ceramic capacitors and multifunctional devices owing to their high dielectric constants and coupled magnetic and ferroelectric properties at room temperature. In this study, cobalt ferrite (CFO)/barium calcium titanate (BCT) composite fibers are prepared from BCT and CFO sols by an electrospinning method, and are then oriented by magnetic fields and sintered at high temperatures. The effects of magnetic fields and CFO contents on the nanostructures and magnetoelectric properties of the composites are investigated. Strong coupling between magnetic and ferroelectric properties occurs in CFO/BCT composites with magnetic orientation. More interestingly, the dielectric constants of CFO/BCT composites with magnetic orientation are found to be enhanced (by ∼1.5–3.5 times) as compared with those of BCT and CFO/BCT without magnetic orientation. The boost of dielectric constants of magnetic-field orientated CFO/BCT is attributed to the magneto-electrical coupling between CFO and BCT, where the polar domains of BCT are pinned by the orientated CFO. Therefore, this work not only provides a novel and effective approach in enhancing the dielectric constants of ceramic ferroelectrics, which is of tremendous value for industrial applications, but also elucidates the interaction mechanisms between ferromagnetic phase and ferroelectric phase in multiferroic compounds. [ABSTRACT FROM AUTHOR]

In this work, a modified solvothermal method has been developed to synthesize few layers of tungsten disulfide-nanosheets(WS2-NS). Different types of surfactants were also employed in the modified solvothermal method with respect to the original procedure. As-prepared WS2 samples were characterized by XRD, TEM, and Raman spectrum. The results showed that the obtained WS2-NS were consisted of 1-10 atomic layers. Importantly, the effects of surfactant on the morphology formation of WS2-NS were investigated. A possible growth mechanism is presented to explain the formation of WS2-NS. [ABSTRACT FROM AUTHOR]

Redox-sensitive potassium channels consisting of the voltage-gated K + (K V ) channel pore subunit K V 1.5 regulate resting membrane potential and thereby contractility of vascular smooth muscle cells. Members of the K V 1 family associate with cytosolic auxiliary β subunits, which are members of the aldo-keto reductase (AKR) superfamily (AKR6A subfamily). The Kvβ subunits have been proposed to regulate Kv1 gating via pyridine nucleotide cofactor binding. However, the molecular identity of K V β subunits that associate with native K V 1.5 channels in the vasculature is unknown. Here, we examined mRNA and protein expression of K V β subunits and tested whether K V β isoforms interact with K V 1.5 channels in murine coronary arteries. We detected K V β1 (AKR6A3), K V β2 (AKR6A5) and K V β3 (AKR6A9) transcripts and K V β1 and K V β2 protein in left anterior descending coronary arteries by real time quantitative PCR and Western blot, respectively. In situ proximity ligation assays indicated abundant protein-protein interactions between K V 1.5/K V β1, K V 1.5/K V β2 and K V β1/β2 in coronary arterial myocytes. Confocal microscopy and membrane fractionation analyses suggest that arterial myocytes from K V β2-null mice have reduced abundance of sarcolemmal K V 1.5. Together, data suggest that in coronary arterial myocytes, K V 1.5 channels predominantly associate with K V β1 and K V β2 proteins and that K V β2 performs a chaperone function for K V 1.5 channels in arterial myocytes, thereby facilitating Kv1α trafficking and membrane localization. [ABSTRACT FROM AUTHOR]

It is a challenging issue to fully consider the radiation interaction among floating bodies in a large array configuration. It requires large computational efforts to resolve the interaction matrix of floaters oscillating independently with 6 degrees of freedom (DoF). Obviously, when the distance between 2 floaters is large enough, their interaction will gradually vanish. It inspires the present study to investigate a cut-off radius, outside which the hydrodynamic interaction can be ignored. It should be noted that the computational efficiency and accuracy is a pair of contradictions: a large cut-off radius is always accompanied by a high accuracy, but requires more computational efforts, and vice versa. The objective of the present study is to quantify the interaction effect and to find an optimal cut-off radius which could reduce the computational time while ensuring a satisfactory accuracy in engineering practice. Based on the potential flow theory, we calculated the hydrodynamic interaction among multiple rectangular boxes and eventually quantified the interaction effects determined by the oscillating frequency and separating distance. Some critical curves of various truncation errors (E t) were obtained, showing whether the hydrodynamic interaction effects can be neglected, were depicted. The results from two case studies showed that the present cut-off scheme could provide a very reliable prediction of the hydrodynamic responses of multiple floating bodies in an array, while the computational time was significantly saved. • A cut-off scheme is proposed to model large arrays of modularized floating structures. • The radiation interaction effects among multiple rectangular boxes are quantified. • Some critical curves showing the optimal cut-off radius are depicted. • Two cases are designed to examine the accuracy and efficiency of the proposed scheme. [ABSTRACT FROM AUTHOR]

The exact mechanism underlying hepatic steatosis in nonalcoholic fatty liver disease (NAFLD) is not clear. Clarifying the full repertoire of microRNAs (miRNAs) in NAFLD rat liver would enhance our understanding of NAFLD pathogenesis. In this study, miRNA expression levels were analyzed in liver tissue from NAFLD Wistar rats, with normal Wistar rats as negative controls. Small RNA libraries were constructed for each sample. A total of 173 conservative miRNAs and 68 potential miRNA candidates were identified. Significant differences in the expression levels of 101 conserved miRNAs were identified between the two groups. The results of GO annotation and KEGG pathway analysis revealed that some miRNAs were likely involved in the process of liver fat deposition. This study represents the first global miRNA profiling of NAFLD Wistar rat livers, and expands the miRNA repertoire for normal livers. Our findings suggest that miRNAs play important roles in liver fat deposition. [ABSTRACT FROM AUTHOR]

(K x Na 1 −x )NbO 3 (KNN) powders with sheet-like morphologies were successfully prepared by the hydrothermal synthesis route combined with subsequent heat-treatment processes. When the heat-treated temperature was 600 °C, the (K x Na 1− x ) NbO 3 (0.6≤ x ≤0.7) perovskite sheets were obtained in the KNN powders. The surface morphology and crystal structure of the KNN sheets were investigated by scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM), respectively. The KNN sheets were in a well-defined hexagonal shape with a thickness of about 100–200 nm and a diameter of 1.5–3 μm. The chemical structure of the KNN sheets was analyzed using Fourier Transform infrared spectroscopy (FTIR) and Raman spectroscopy. A growth mechanism for the sheet-like microstructures was discussed. [ABSTRACT FROM AUTHOR]

Monoclinic (K x Na 1− x )NbO 3 (0.05≤ x ≤0.15) rods were prepared successfully by the hydrothermal synthesis method combined with dissolution–precipitation and subsequent heat-treatment processes. At first, the primary precipitate of the niobate precursor was obtained using Nb 2 O 5 , KOH and NaOH as the initial reactants, and deionized water as the solvent for the hydrothermal synthesis. Interestingly, when the obtained precipitate was dissolved in 90 °C of deionized water and then the solution kept standing till ambient temperature, the secondary precipitate of rod-like niobate (K x Na 6− x )H 2 Nb 6 O 19 ·2H 2 O was formed. After centrifugation, washing, and the subsequent heat treatment of the secondary precipitate sample, the (K x Na 1− x )NbO 3 rods of 1–60 μm in length and 1–5 μm in width were finally prepared. The surface morphology and phase structure of the prouducts were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD), respectively, and the chemical composition of the prouducts were identified by means of energy-dispersive X-ray spectroscopy(EDS). Furthermore, fourier transform infrared spectroscopy (FT-IR) and high-resolution transmission electron microscopy (HRTEM) were employed to investigate the fine structures of the prouducts. This research provides a new approach for the preparation of one-dimensional (K x Na 1− x )NbO 3 material and template grains for the fabrication of lead-free textured alkali niobate piezoelectric ceramics. [ABSTRACT FROM AUTHOR]

Lead-free potassium sodium niobate (KNN) nanorods were synthesized by a modified sol-gel method with freshly homemade niobium hydroxide as niobium source, oxalic acid as chelator, ethanediol as esterifying agent, rochelle salt as potassium and sodium source. The as-synthesized KNN nanorods exhibited a orthorhombic structure with diameter of 150–500 nm and length of 1–2μm. The effects of the sintering temperature and heating rate on the crystal structure and morphology were examined respectively, and the growth process and mechanism were explained. The results showed that the crystalline structure of KNN nanorods was affected by the sintering temperature significantly and that the morphology was mainly affected by the heating rate. At a low heating rate the particles tended to grow into (001) oriented nanorods, while at a rapid heating rate the particles tended to be cube-like structures. In addition, relatively low sintering temperature was beneficial to grain growth along c axis direction due to the low growth energy of c axis in the orthorhombic system. [ABSTRACT FROM PUBLISHER]

Magnetite nanoparticles decorated CNTs/PANI multiphase heterostructures were prepared by polymerization of aniline monomer and an additional process of the coprecipitation of Fe and Fe. Scanning electron microscopy and transmission electron microscopy observation indicated that the monodispersed magnetite nanoparticles were uniformly decorated on the surface of CNTs/PANI. The formation of magnetite nanoparticles on CNTs/PANI was mainly through a preferentially position-selective precipitation process. More interestingly, a portion of FeO nanoparticles was found to form core-shell structures with PANI. The effects of different additional amounts of NHFe(SO)·6HO reactant on the magnetic properties and microwave absorbing performances of CNTs/PANI/FeO heterostructures were investigated. The CNTs/PANI/FeO multiphase heterostructures were proved to be superparamagnetic. The microwave absorption measurement showed that the CNTs/PANI/FeO samples under 1.5 g of NHFe(SO)·6HO condition exhibited much more effective absorption performance. These results suggested the novel CNTs/PANI/FeO multiphase heterostructures with PANI as the second phase may be potential candidate for microwave absorption systems. [ABSTRACT FROM AUTHOR]

Lead-free K0.5Na0.5NbO3(KNN) thin films were prepared on Pt (111) /Ti/SiO2/Si (100) substrates by a polyvinylpyrrolidone (PVP)-modified sol-gel method without any metal alkoxides. The effects of PVP on the crystallization, surface morphology and electrical properties were investigated. It was found that the introduction of PVP into the sol could reduce the annealing temperature, enhance the surface quality and improve the KNN film of (100) oriented growth. Compared with the pure non-PVP-modified KNN thin films, the dielectric and ferroelectric properties of the KNN films were significantly enhanced by adding PVP into the sol. In particular, the PVP-modified KNN films which were annealed at 550°C exhibited relatively saturated polarization-electric field (P-E) hysteresis loops with high remnant polarizationProf 22μC/cm2, dielectric constant of 280 and dielectric loss of 0.09, respectively, indicating promising lead-free piezoelectric film candidate for future applications. [ABSTRACT FROM AUTHOR]

Zn2GeO4–ZnO crystals with base diameter of approximately 400 nm and height of 400–800 nm were successfully prepared by a facile combustion oxidation at 960°C. No catalyst or carrier gases were used. XRD, SEM and SPM analysis revealed that Zn2GeO4and ZnO have grown to micro–nanometer screws–cone–like parasitic crystals, and they showed obvious surface traces of spiral growth. SPAM examination showed that the section fine lines reticular was contained in the inside of the as–prepared crystals. The spiral growth process were proposed. The photocatalytic activity experiment indicated that the photocatalytic activity of the Zn2GeO4–ZnO crystals was significantly higher than that of nano–tetrapod ZnO. [ABSTRACT FROM AUTHOR]

Highlights: [•] The fabrication process of the PVA–Ag–GNS is very facile and inexpensive. [•] The PVA–Ag–GNS is biocompatible and highly NIR-SERS active, with the EF of 108. [•] DNA adsorbed on silver surface via the intra-annular nitrogen of the DNA bases. [•] DNA bases in DNA adsorbed with the silver surface is in the order T

Abstract: Porcine reproductive and respiratory syndrome virus (PRRSV) has recently caused catastrophic losses in swine industry worldwide. The commercial vaccines only provide a limited protection against PRRSV infection. At present, DNA vaccine is the focus on the new vaccines. The gene fragment (p28) coding for the molecular adjuvants complement protein C3d (mC3d) from BALB/c mouse was cloned and expressed as a fusion protein for its application in the vaccine study of mice. Three potential vaccines construct units were engineered to contain two, four and six copies of mC3d-p28 coding gene linked to the GP5 gene of PRRSV and one vaccine expressing GP5 alone (pcDNA3.1-GP5) was constructed. Subsequently, the vaccines’ abilities to elicit the humoral and cellular immune responses were investigated in mice. These results showed that significantly enhanced GP5-specific ELISA antibody, GP5-specific neutralizing antibody, IFN-γ level, and IL-4 level, could be induced in mice immunized with DNA construct units encoding the pcDNA3.1-C3d-p28.n-GP5 than those received DNA vaccine expressing GP5 alone (pcDNA3.1-GP5). Analysis of the immunogenicity of different repeats of mC3d-p28 revealed that mC3d-p28 had an enhancing effect on the immunogenicity of antigens, and that six or more repeats of mC3d-p28 may be necessary for efficient enhancement of antigen specific immune responses. This approach may provide a new strategy for the development of efficient vaccines against the PRRSV for pigs in the future. [ABSTRACT FROM AUTHOR]

Abstract: A highly selective naked-eye detection of ClO− is successfully established with probe 1 by taking advantage of the oxidation transformation of p-methoxyphenol into benzoquinone with ClO− and the ICT absorption within the electron donor–acceptor compound. The color of the solution of probe 1 was changed, obviously upon addition of ClO− and ClO− with concentration as low as 1.74μM can be analyzed in aqueous solution with probe 1. Moreover, the interferences of other anions can be neglected. [ABSTRACT FROM AUTHOR]

Abstract: Two new organic gelators 1 and 2 based on the silole (silacyclopentadiene) framework were designed with the end to develop switchable fluorescent organogels, by making use of the aggregation-induced emission (AIE) feature of silole derivatives. As for other silole derivatives, compounds 1 and 2 exhibited AIE behavior as indicated by the significant fluorescence enhancement by introducing water to the THF solutions. Compounds 1 and 2 can gel hexane, methylcyclohexane and heptane. Large fluorescence enhancement was observed for compounds 1 and 2 after gelation. Moreover, their fluorescence intensities can be changed reversibly accompanying the gel–solution transition through alternating cooling and heating. Therefore, thermally-driven fluorescence switches can be achieved with organogels based on 1 and 2. [Copyright &y& Elsevier]

Abstract: By combining the features of photochromic spiropyran and the host–guest inclusion complex between the adamantyl (AD) and β-cyclodextrin (β-CD) derivatives, we report a temperature-gated molecular fluorescence switch. [Copyright &y& Elsevier]

Abstract: An expressed sequence tag (EST) sequencing project has produced over 15,000 partial cDNA sequences from the equine pathogen Sarcocystis neurona. While many of the sequences are clear homologues of previously characterized genes, a significant number of the S. neurona ESTs do not exhibit similarity to anything in the extensive sequence databases that have been generated. In an effort to characterize parasite proteins that are novel to S. neurona, a seemingly unique gene was selected for further investigation based on its abundant representation in the collection of ESTs and the predicted presence of a signal peptide and glycolipid anchor addition on the encoded protein. The gene was expressed in E. coli, and monospecific polyclonal antiserum against the recombinant protein was produced by immunization of a rabbit. Characterization of the native protein in S. neurona merozoites and schizonts revealed that it is a low molecular weight surface protein that is expressed throughout intracellular development of the parasite. The protein was designated Surface Protein 1 (SPR1) to reflect its display on the outer surface of merozoites and to distinguish it from the ubiquitous SAG/SRS surface antigens of the heteroxenous Coccidia. Interestingly, infection assays in the presence of the polyclonal antiserum suggested that SnSPR1 plays some role in attachment and/or invasion of host cells by S. neurona merozoites. The work described herein represents a general template for selecting and characterizing the various unidentified gene sequences that are plentiful in the EST databases for S. neurona and other apicomplexans. Furthermore, this study illustrates the value of investigating these novel sequences since it can offer new candidates for diagnostic or vaccine development while also providing greater insight into the biology of these parasites. [Copyright &y& Elsevier]

Abstract: A new derivative of 4-(N,N-dimethylamino)benzonitrile (DMABN) (compound 1) with TTF unit is reported. Compound 1 exhibits dual fluorescence, and moreover the dual fluorescence behavior can be modulated by reversible oxidation and reduction of TTF unit of 1 either chemically or electrochemically. Accordingly, a new molecular fluorescence switch is realized by coupling the features of TTF and DMABN. [Copyright &y& Elsevier]

Abstract: A new binaphthalene (R)-1 with two substituted TTF and trichloroquinone units is reported. Both absorption and ESR spectral studies show that electron transfer occurs between TTF and trichloroquinone units of (R)-1 in the presence of metal ions (Pb2+, Sc3+, Zn2+, and Ca2+). We also propose a possible mechanism for this electron transfer process. But, the CD spectral change of (R)-1 in the presence of metal ions is rather small. [Copyright &y& Elsevier]

Abstract: DMABN (4-N,N-dimethylaminobenzonitrile) derivatives 1 and 2 were designed as new ratiometric fluorescent sensors for saccharides and fluoride ion (F−), respectively, based on the TICT (twisted intramolecular charge transfer) mechanism. [Copyright &y& Elsevier]

Abstract: A new TTF–perylene diimide dyad 1 with a pentaoxa-heptadecane chain as the spacer was synthesized and characterized. Absorption and fluorescent spectral studies of dyad 1 and reference compounds 2 and 3 indicate that aggregation of dyad 1 and compound 2 occurs in the presence of metal ions. Such metal-ions-induced aggregation is likely due to the synergic action of the coordination of metal ions with the oligoethylene glycol unit and the π–π stacking of the perylene diimide unit. [Copyright &y& Elsevier]

Abstract: Sarcocystis neurona is an apicomplexan parasite that is the major cause of equine protozoal myeloencephalitis (EPM). The biology of this pathogen remains poorly understood in part due to unavailability of molecular genetic tools. Hence, with an objective to develop DNA transfection capabilities for S. neurona, the 5′ flanking region of the SnSAG1 gene was isolated from a genomic library and used to construct expression plasmids. In transient assays, the reporter molecules β-galactosidase (β-gal) and yellow fluorescent protein (YFP) could be detected in electroporated S. neurona, thereby confirming the feasibility of transgene expression in this organism. Stable transformation of S. neurona was achieved using a mutant dihydrofolate reductase thymidylate synthase (DHFR-TS) gene of Toxoplasma gondii that confers resistance to pyrimethamine. This selection system was used to create transgenic S. neurona that stably express β-gal and YFP. As shown in this study, these transgenic clones can be useful for analyzing growth rate of parasites in vitro and for assessing drug sensitivities. More importantly, the DNA transfection methods described herein should greatly facilitate studies examining intracellular parasitism by this important coccidian pathogen. [Copyright &y& Elsevier]

Abstract: A putative nucleoside triphosphate hydrolase (NTPase) gene was identified in a database of expressed sequence tags (ESTs) from the apicomplexan parasite Sarcocystis neurona. Analysis of culture-derived S. neurona merozoites demonstrated a dithiol-dependent NTPase activity, consistent with the presence of a homologue to the TgNTPases of Toxoplasma gondii. A complete cDNA was obtained for the S. neurona gene and the predicted amino acid sequence shared 38% identity with the two TgNTPase isoforms from T. gondii. Based on the obvious homology, the S. neurona protein was designated SnNTP1. The SnNTP1 cDNA encodes a polypeptide of 714 amino acids with a predicted 22-residue signal peptide and an estimated mature molecular mass of 70kDa. Southern blot analysis of the SnNTP1 locus revealed that the gene exists as a single copy in the S. neurona genome, unlike the multiple gene copies that have been observed in T. gondii and Neospora caninum. Analyses of the SnNTP1 protein demonstrated that it is soluble and secreted into the culture medium by extracellular merozoites. Surprisingly, indirect immunofluorescence analysis of intracellular S. neurona revealed apical localisation of SnNTP1 and temporal expression characteristics that are comparable with the microneme protein SnMIC10. The absence of SnNTP1 during much of endopolygeny implies that this protein does not serve a function during intracellular growth and development of S. neurona schizonts. Instead, SnNTP1 may play a role in events that occur during or proximal to merozoite egress from and/or invasion into cells. [Copyright &y& Elsevier]

Abstract: Compound 1 containing two nitronyl nitroxide units bridged by tetra(ethyleneoxy) was designed and synthesized for sensing metal ions, by taking the features of nitronyl nitroxides: a chromophore showing absorption in visible range, reversible oxidation/reduction and coordination to metal ions. The absorption spectrum of 1 was altered markedly upon mixing with a few rare earth metal ions and some transition metal ions. Moreover, the oxidation potential of 1 was shifted to more positive range in the presence of metal ions including Pb2+, Ba2+, and Ca2+. Thus, compound 1 can sense metal ions both spectroscopically and electrochemically. [Copyright &y& Elsevier]

Abstract: Strong pyrene excimer emission was observed for a new pyrene–thymine dyad that can be easily synthesized in the presence of Hg2+ ion. But, the enhancement of pyrene excimer emission was not detected in the presence of other metal ions. As a result, this new pyrene–thymine dyad is suited for use as a sensitive and selective “turn on” fluorescent chemosensor for Hg(II) ion. [Copyright &y& Elsevier]

Abstract: Two new helical Cu(II) coordination polymers, [Cu(2,2′-bpy)(Hsgly)]Cl·2H2O(H2sgly= N-(2-hydroxylbenzyl)glycine) (1) and [Cu(2,2′-bpy)(Hsala)](NO3)·2H2O(H2sala= N-(2-hydroxylbenzyl)-l-alanine) (2) were synthesized. Single crystal X-ray diffraction analysis indicated that both complexes showed helical chains arrangement of Cu(II) centers bridged by carboxyl groups. The magnetic measurements showed complex 1 exhibited ferromagnetic interaction while there was no interaction between the Cu(II) centers in complex 2. [Copyright &y& Elsevier]

Abstract: The fluorescence of a pyrene-arylmaleimide dyad and its Diels–Alder adduct can be thermally modulated through reversible Diels–Alder reaction of arylmaleimide unit with furan. Moreover, the fluorescence intensities of the Diels–Alder adduct of dyad 1 with furan vary linearly with the temperatures of the corresponding solutions, demonstrating that these molecules are interesting compounds for studies of fluorescent molecular thermometers. [Copyright &y& Elsevier]

The fluorescence of pyrene can be quenched by spiropyran (SP) due to the intermolecular photoinduced electron transfer (PET). However, the fluorescence of the ensemble solution of pyrene (PY) and SP restores nearly to the initial value of the pure solution of PY after the consecutive actions of Fe(ClO4)3 and UV light. This is owing to the fact that the open form of spiropyan can be coordinated to ferric ion, and as a result the reversible photo-control of the intermolecular PET reaction from SP to the excited PY can be realized under light irradiation in the presence of ferric ion. [Copyright &y& Elsevier]

Two new charge-transfer (CT) salts: (ET)2·SO3CF3 and (ET)·ClO4 were prepared by chemical oxidation of ET with AgSO3CF3 and AgClO4, respectively. Their crystal structures were determined: monoclinic system, Cc, a=35.239(7) A˚, b=6.5440(13) A˚, c=14.646(3) A˚, β=110.26(3)°, V=3168.5(11) A˚3 for (ET)2·SO3CF3; monoclinic system, C2/c, a=15.981(3) A˚, b=10.627(2) A˚, c=11.495(2) A˚, β=120.61(3)°, V=1680.2(6) A˚3 for (ET)·ClO4. Electrical conductivity measurements indicate that (ET)2·SO3CF3 shows semi-conducting behaviour with room temperature conductivity of 0.29 S cm−1, while (ET)·ClO4 is an insulator. [Copyright &y& Elsevier]

Quinoline and N-methyl quinolinium-substituted nitronyl nitroxides 1 and 2 were prepared, and their crystal structures were determined. Thermal variance of their molar magnetic susceptibilities was measured with SQUID, and the results indicated that they both showed antiferromagnetic behavior. Atomic spin density in 1 and 2 was calculated with ab initio method, and magneto-structural correlation was discussed. [Copyright &y& Elsevier]

The fluorescence of pyrenemethylamine hydrochloride was reversibly modulated by light in the presence of spiropyran. The results demonstrated the signal communication through proton transfer between one three-state molecular switch based on spiropyran and one fluorescence molecular switch. [Copyright &y& Elsevier]

Three donor–acceptor–donor triads 1–3 consisting of tetrathiafulvalene units attached to perylene diimides by flexible and rigid spacers were synthesized and characterized. UV/vis spectroscopic and cyclic voltammetric results indicate that they all show negligible intramolecular charge transfer interaction in their ground states. As compared to the reference compound 21, triads 1–3 display reduced fluorescence and their fluorescence lifetimes are shortened, which is probably owing to the photoinduced electron transfer interactions between the PI units and TTF units. The different photophysical behaviors between 1 and 2 (and 3) might be due to their difference in the spatial separation of TTF and PI units. It is preliminarily found that the steric hindrance of the groups attached to TTF units can affect their photostability. [Copyright &y& Elsevier]

Electron donors with two and four pyridine groups 1–6 were synthesized and characterized. Their oxidation potentials were determined with cyclic voltammetry. A 3D supramolecular complex was formed between 3 and chloranilic acid (CA), and the crystal structure of this neutral complex was determined. Conducting LB films with room temperature conductivity up to 1.1×10−3 S cm−1 were prepared from electron donors 1 and 4. [Copyright &y& Elsevier]

Carbon-based materials/metal hydroxide composite materials are one type of the most promising electrode materials for improving the performance of supercapacitors. They have the advantages of low cost, controllable morphology, high theoretical capacity, and excellent stability. In this study, nickel hydroxide nanosheets were grown vertically on the surface of carbon nanotubes (Ni(OH)2@CNTs) by a wet chemical method at low temperatures. The unique spatial configuration provides a larger specific surface area and exposes more electrochemically active sites, which is more conducive to improving electrochemical performance. The prominent conductivity of carbon nanotubes can quickly transfer electrons and improve the electrochemical cycling stability of the composite. The Ni(OH)2@CNTs composite exhibits excellent electrochemical performance with a specific capacitance of 1234 F g−1 at a current density of 1 A g−1 under a three-electrode system. In addition, an asymmetric supercapacitor (ASC) assembled using Ni(OH)2@CNTs as a cathode material shows an energy density of 65.63 W h kg−1 at a power density of 752.39 W kg−1 and a capacity retention rate of 85.9% after 10 000 cycles at a current density of 2 A g−1. The results indicate that Ni(OH)2@CNTs has prospects for application as a cathode material in high-performance supercapacitors. [ABSTRACT FROM AUTHOR]