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Background Bipolar disorder (BD) is a severe mental illness that affects more than 1% the world's population with high recurrence rates and a series of comorbidities. Cognitive dysfunction is an endophenotype of BD, but sex influences in cognitive impairment remains unclear. Method We evaluated the performance of 139 patients with first-diagnosed, drug-naive BD (44 males and 95 females) and 92 healthy controls (24 males and 68 females) using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) scale and the Stroop color–word test. Result Immediate memory, visuospatial/constructional ability, language, attention, delayed memory, total RBANS score, and Stroop color–word scores were significantly lower in patients with first-diagnosed, drug-naive BD than healthy participants. Thus, male patients had worse attention and delayed memory scores compared with female patients with BD. Importantly, a worse performance in visuospatial/constructional ability was negatively associated with the Young Mania Rating Scale score in male patients only. Conclusion Male patients with first-diagnosed, drug-naive bipolar disorder had worse cognitive dysfunction than female patients in attention and delayed memory. Cognitive deficits were correlated with mania severity only in male patients. These findings reveal the sexual dimorphism in the cognitive deficits of early BD patients with mild and moderated symptoms for further pathophysiological exploration.

Laminated ZrB2–SiC/SiCw (LZSw) was prepared via tap-casting and hot-pressing processes. The R-curve behavior of the ceramic materials was evaluated using indentation-strength method. The flexural strength and fracture toughness values of the materials were found to reach up to 607 MPa and 14.5 MPa·m1/2, respectively, when employing SiC whiskers as a strong interface. The indentation strength was observed to decrease upon an increase in the indentation load, and compared with the steep decreasing trend exhibited by the monolithic ZrB2–SiC (ZS20), LZSw showed a slow decreasing trend. LZSw showed a distinct upward trend in its R-curve, which was found to be dependent on the indentation collapse caused by its laminated structure and the increasing crack propagation path as a result of crack deflection and branching mechanisms.

To improve ablation resistance of graphite, SiC/ZrB2-SiC/ZrB2/SiC coating was prepared by pack cementation and CVD. SiC/ZrB2–SiC/ZrB2/SiC coating showed excellent ablation resistance, its mass and linear ablation rate were only 0.27 mg/s and 0.57 μm/s after ablation under oxyacetylene flame for 298 s. CVD ZrB2/SiC layer significantly improved the ablation resistance of SiC/ZrB2–SiC/ZrB2/SiC coating. During ablation, the surface temperature gradually increased until it stabilized around 2220 °C. The surface temperature response in different stages was affected by layered microstructure evolution and emissivity of different layers.

Recently, super-resolution methods pursue visual pleasant details attract more attention in academic circle. Unlike former accurate driving models, they leverage new losses measured the difference of features extracting from a pre-trained deep learning model. Moreover, the popular GANs structure are introduced to approach better outputs. In general, these new visual feeling promoting losses are constrained by the learning ability of model and effected by the weakness of GANs. In order to address these problems, we propose a novel SR method to generating abundant details. Based on former SR methods and texture generated models, we combine new model constructure and integrated loss function to achieve our goal. The new constructure derives from the very thought that more information from the LR input leads to more accurate results. The new integrated loss try to decrease the weakness of each one by corresponding loss.. Experiments show that our model achieves higher quality generations than former methods.

Women with bipolar disorder (BD) present a high prevalence of polycystic ovary syndrome (PCOS) and other reproductive disorders even before diagnosis or treatment of the disease. Postulations on the potential molecular mechanisms of comorbid PCOS in women with BD remain limited to influence of medications and need further extension.This review focuses on evidence suggesting that common metabolic and immune disorders may play an important role in the development of BD and PCOS.The literature covered in this review suggests that metabolic and immune disorders, including the dysfunction of the hypothalamic-pituitary-adrenal axis, chronic inflammatory state, gut microbial alterations, adipokine alterations and circadian rhythm disturbance, are observed in patients with BD and PCOS. Such disorders may be responsible for the increased prevalence of PCOS in the BD population and indicate a susceptibility gene overlap between the two diseases. Current evidence supports postulations of common metabolic and immune disorders as endophenotype in BD as well as in PCOS.Metabolic and immune disorders may be responsible for the comorbid PCOS in the BD population. The identification of hallmark metabolic and immune features common to these two diseases will contribute to the clarification of the effect of BD on the reproductive endocrine function and development of symptomatic treatments targeting the biomarkers of the two diseases.

In this paper, a 3D sandwich structured hybrid of gold nanoparticles (AuNPs) decorated MnO2/graphene (GP)-carbon nanotubes (CNTs) was prepared via three steps, and the resultant AuNPs/MnO2/GP-CNTs hybrids was characterized by field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX) detector and X-ray diffraction (XRD) spectrum, respectively. In this structure, the peeled GP nanosheets from CNTs work as linkers with CNTs to form 3D scaffold for facilitating fast electron conduction. The MnO2 nanoparticles well distributed on the GP-CNTs scaffold have excellent electrocatalytic activities towards H2O2, serving as active materials for fabricating electrochemical H2O2 sensors. AuNPs (

Background Klebsiella pneumonia (KP) and carbapenem-resistant Klebsiella pneumonia (CRKP) lung infections significantly increase the morbidity and mortality of pneumonia. Recent studies have shown that baculoviral IAP repeat-containing 3 (Birc3) plays an important role in the prevention and treatment of pneumonia. However, the role of Birc3 in CRKP-induced pneumonia has not been widely reported. Methods In vivo, we successfully established a mouse model of pneumonia induced by KP and CRKP. In vitro, we established a macrophage model treated with KP and CRKP. The phagocytosis of macrophages treated with CRKP was measured by Flow cytometry and coated plate counting. STRING and Co-IP assays were used to predict and verify the relationship between Birc3 and toll-like receptor 4 (TLR4) or myeloid differentiation factor 88 (Myd88). HE staining was used to detect the lung pathological changes of anti-Birc3 IgG inhibited CRKP-induced inflammatory cells. The levels of inflammatory factors and proteins were detected by ELISA and Western blot, respectively. Results The phagocytic ability of macrophages was reduced, and the cytokine storm was enhanced in CRKP treated Raw264.7 cells. Macrophages treated with CRKP impaired phagocytosis. Birc3 could interact with TLR4 and MyD88. Anti-Birc3 IgG inhibited CRKP-induced inflammatory cell lung infiltration. In addition, mice treated with anti-Birc3 IgG improved the CRKP-induced inflammatory cell lung infiltration, bacterial spread, and cytokine storm by inhibiting the Birc3/TLR4/Myd88 signaling pathway. Conclusion The results suggest that Birc3 may serve as a target for the treatment of bacterial infection and lung inflammation in CRKP-induced pneumonia.

Port city is an important part of marine economic activities, whose development contributes to the connection of economic and environment between home and abroad. Sustainability of port cities not only can enhance the competitiveness of port cities, but also affects the city development process and characteristics. Therefore, it is pivotal to evaluate sustainability of port cities in advance. However, existing research on sustainable port cities is quite limited. And most of them are limited to the qualitative perspective, with little quantitative analysis. Therefore, this paper adopts a novel hybrid model THPD to evaluate sustainable port cities, expanding sustainability theories by taking port cities as research object. 21 port cities in China are selected for quantitative study. The results display that the sustainable level of port cities in China is at a medium level. The weaknesses and critical factors are varied, which points out the improvement direction for sustainable port cities.

Realizing the coordinated development of regional emission reduction and low-carbon transportation has become a hot issue concerned by governments worldwide. Using data from 30 provinces of China’s transport sector, this paper investigates and evaluates the regional differences of carbon emission intensity (CEI). Additionally, we employ the extended STIRPAT (stochastic impacts by regression on population, affluence and technology) and GTWR (geographically and temporally weighted regression) model to reveal the influence of driving factors on CEI from spatial-temporal perspectives. The results indicate the following: (1) CEI tends to decrease and presents a pattern of low in the southeast and high in the northwest in space. (2) The eastern region has the greatest degree of regional difference, and the central region has the smallest. The major reason for the widening of the overall differences in China is the within-group differences in the three geographical regions. (3) CEI in China’s transport sector has regional characteristics, and the effect of urbanization, energy structure, population scale and industrial structure on CEI vary among the regions. Energy intensity occupies a pivotal position among all the driving factors and poses a positive impact on the CEI of transport sector.

The free vibration of Duffing oscillator with time-delayed fractional-order Proportional-Integral-Derivative (FOPID) controller based on displacement feedback is studied. The second-order approximate analytical solution is obtained by KBM asymptotic method. The effects of the parameters in FOPID controller on the dynamical properties are characterized by some equivalent parameters. The correctness of the approximate analytical results is verified by the numerical results. The effects of the time-delayed FOPID controller with displacement feedback on control performances of Duffing oscillator are analyzed in detail by time response, and the stability conditions of zero solution and periodic motions are also presented. Finally, the control performances on Duffing oscillator with large damping are further analyzed. And the results show that one could take the advantage of time delay, when the parameters of time-delayed FOPID controller are chosen reasonably.

The aqueous NiOOH nanosheets were synthesized using a hydrothermal method via a surfactant template under mild reaction conditions. The as-prepared products were characterized by atomic force microscopy (AFM), X-ray diffraction (XRD) and scanning electron microscopy (SEM), the results of which indicated that ultrathin and porous NiOOH nanosheets with a thickness of only several nanometers have been obtained. The obtained NiOOH nanosheets were subsequently assembled on electrochemically pretreated glassy carbon (EPGC) electrode through a simple physical bath deposition method to form NiOOH/EPGC electrode. SEM, energy dispersive X-ray spectroscopy (EDX) and electrochemical impedance spectroscopy (EIS) proved the successful assembly of NiOOH on EPGC surface. The effective deposition of NiOOH electrocatalyst on electrode is believed to result from the higher surface area and higher surface concentration of C O functional groups existing on EPGC surface. Glucose and methanol were selected as model molecules to investigate the electrocatalytic performance of NiOOH/EPGC electrode. The electrochemical experiments revealed that a favorable activity of the NiOOH/EPGC electrode toward electrooxidation of glucose and methanol has been found. The present NiOOH/EPGC based amperometric sensor exhibited a rapid and highly sensitive response to glucose and methanol, which might find promising applications in medical applications, biological fuel cells and food industries.

The rice weevil Sitophilus oryzae (L.) is an important pest of stored sorghum ( Sorghum bicolor L. Moench). Quantitative trait loci (QTL) associated with rice weevil resistance was analyzed using a F 10 recombinant inbred line (RIL) population derived from the cross 654 (susceptible) × LTR108 (resistant). Grain weight losses (GWL), flour production (FP), and percentage kernels damaged (PKD) were evaluated across two trails. A total of 21 QTLs for GWL, FP, and PKD were identified. The phenotypic variation explained by individual QTL varied from 4.14% to 15.51%. Both parents contributed resistance alleles. Several main effect QTLs affecting GWL, FP, and PKD were mapped to the same regions on chromosome 2. The identification of genomic regions associated with rice weevil resistance will be useful to understand the resistance mechanism and improve rice weevil resistance of sorghum by marker-aided approaches.

Daisy-like hexagonal WO3 and rose-like monoclinic WO3 hierarchical structures were fabricated via facile hydrothermal technic in this work. The acetone sensing properties of the products were evaluated in detail. The results reveal that the hexagonal daisy-like WO3 sensor exhibits high sensitivity, good selectivity, rapid response/recovery, and remarkable repeatability to acetone (0.2∼200 ppm) at 260 °C. The outstanding sensing performance is attributed to the synergistic effects of the dominant (002) facets and the intracrystalline tunnel structure of hexagonal phase. The morphology formation mechanism and the acetone sensing mechanism are discussed. This work has practical significance for environmental monitoring of acetone as well as for breath diagnosis of diabetes.

This study explores the efficacy and mechanism by which octreotide (OCT) alleviates paraquat (PQ)-induced pancreatic injury. Twenty-four adult male rats were randomly divided into three groups: the normal control (NC), PQ poisoning, and OCT treatment groups. The PQ-induced pancreatic injury rat model was established by administering PQ (120 mg/kg). Treatment group rats received OCT (8 μg/kg body weight) every 8 h by subcutaneous injection, 1 h after PQ administration. Rats were euthanized 24 h after PQ injection. Serum amylase, lipase, tumor necrosis factor-α, and interleukin-6 levels were markedly increased in the PQ group versus the NC group. In pancreatic tissue, PQ poisoning drastically induced necrosis and increased inflammatory cytokine and oxidative stress marker levels. Compared with the PQ group, OCT reduced pancreatic damage and histological scores, serum amylase, lipase, and inflammatory cytokine levels, as well as oxidative stress. OCT demonstrates protective effects against PQ-induced pancreatic damage through anti-inflammatory and antioxidant actions.

This paper presented an electrochemical aptasensor for dopamine detection with high sensitivity and selectivity. The electrochemical signal was amplified by electrochemical-chemical redox cycling with tris(2-carboxyethyl)phosphine (TCEP) as the reducing reagent. Specifically, dopamine captured by the aptamer-covered gold nanoparticles-modified carbon glass electrode was cycled by TCEP after its electrochemical oxidization, enabling an increase in the anodic current. Because of the high specificity and strong binding affinity of aptamer to dopamine, the sensor is fairly selective in not responding to common interferences. The results of chronoamperometry indicated that this aptasensor allowed for the detection of dopamine in a linear concentration range of 5 nM to 0.5 μM. The detection limit was estimated to be 1.8 nM. Additionally, the aptasensor was successfully applied to determine dopamine spiked in the serum sample and gave recoveries ranging from 94.6 to 107.2%. This work would also be valuable for development of new types of electrochemical sensors for determination of other electroactive substances by marrying specific receptors and effective reducing or oxidizing reagents.

In this study, highly efficient visible-light-driven Ag3PO4/MoS2 composite photocatalysts with different weight ratios of MoS2 were prepared via the ethanol-water mixed solvents precipitation method and characterized by ICP, XRD, HRTEM, FE-SEM, BET, XPS, UV–vis DRS and PL analysis. Under visible-light irradiation, Ag3PO4/MoS2 composites exhibit excellent photocatalytic activity towards the degradation of organic pollutants in aqueous solution. The optimal composite with 0.648 wt% MoS2 content exhibits the highest photocatalytic activity, which can degrade almost all MB under visible-light irradiation within 60 min. Recycling experiments confirmed that the Ag3PO4/MoS2 catalysts had superior cycle performance and stability. The photocatalytic activity enhancement of Ag3PO4/MoS2 photocatalysts can be mainly ascribed to the efficient separation of photogenerated charge carriers and the stronger oxidation and reduction ability through a Z-scheme system composed of Ag3PO4, Ag and MoS2, in which Ag particles act as the charge separation center. The high photocatalytic stability is due to the successful inhibition of the photocorrosion of Ag3PO4 by transferring the photogenerated electrons of Ag3PO4 to MoS2. The evidence of the Z-scheme photocatalytic mechanism of the composite photocatalysts could be obtained from the active species trapping experiments and the photoluminescence technique.

Soluble amyloid-β oligomer (AβO) is believed to be a reliable molecular biomarker for the diagnosis of Alzheimer's disease (AD) because of its high toxicity for neuronal synapse and higher concentration level in cerebrospinal fluid sample from AD patient than from control individual. At present, it is critical to develop a simple method for AβO detection with low cost as well as high sensitivity and selectivity. In this work, we reported an antibody-free electrochemical method for the detection of AβO based on the specific interaction between AβO and PrP(95–110) peptide, a segment of cellular prion protein. Specifically, cysteine-containing PrP(95–110) peptide was first immobilized on a gold electrode for the capture of AβO. Then, alkaline phosphatase-conjugated PrP(95–110) was used for the recognition of the captured AβO and the generation of electroactive species. Furthermore, an “outer-sphere to inner-sphere” electrochemical–chemical–chemical (ECC) redox cycling using ferrocene methanol as the redox mediator was employed to enhance the detection sensitivity. As a result, a detection limit of 3 pM for equivalent monomer was achieved. The amenability of this method to AβO analysis in a biological matrix was demonstrated by assays of AβO in serum samples.

We reported a new approach for the immobilization of acetylcholinesterase (AChE) on glass carbon electrode by employing ferrocene (Fc)-phenylalanine (denoted as Fc-F) hydrogels. To demonstrate the application of the modified electrode, chlorpyrifos, an AChE inhibitor, was determined. Specifically, with the addition of substrate acetylthiocholine, the enzymatic conversion from acetylthiocholine to thiocholine by AChE proceeded. The AChE/Fc-F modified electrode exhibited good electro-catalytic performance for the oxidation of the enzymatically produced thiocholine. In this process, the oxidized forms of Fc (Fc+) in the hydrogels were reduced by thiocholine, resulting in an increase in the anodic current of Fc. Based on the inhibition of the AChE activity, chlorpyrifos was determined with a detection limit of 3 nM. Analytical merits (e.g. stability, dynamic range, reproducibility, detection level, selectivity and regeneration) were also evaluated.

A sandwich strategy for highly sensitive DNA analysis has been proposed by measuring the hindered diffusion flux of Fe(CN) 6 3− caused by DNA hybridization in nanopores of a porous anodic alumina (PAA) membrane. The flux of Fe(CN) 6 3− passing through the PAA nanopores is recorded using an electrochemical detector made with Au film sputtered on one face of PAA membrane. To achieve target DNA analysis, the PAA membranes are functionalized with capture DNA and followed by the hybridization event that gives rise to the pore blocking due to the synergetic effect of steric and electrostatic repulsion in the confined nanopores. Both of these two effects can be amplified by using 12-nm Au nanoparticle tags labeled with single strand DNA to perform a sandwich assay, which further amplified detection signals evidenced from the decreased flux of Fe(CN) 6 3− . Based on this strategy, the proposed DNA biosensor gives a detection limit of 1 pM. This thin piece of membrane sensor, coupled with the simple electrochemical system, fast response and high sensitivity, show potentials to be successfully used for bioanalysis.

l-Ascorbic acid 2-phosphate (AAP) is an optimal substrate for alkaline phosphatase (ALP) in electrochemical bioassays because of its low cost, good water solubility, less electrode passivation and high signal-to-background ratio. However, developing of electrochemical sensors with AAP as the enzyme substrate on self-assembled monolayer (SAM)-covered electrode is limited because the insulating SAM hinders the electron transfer between the electrode and ascorbic acid (AA, the enzymatic product of AAP). In this work, we first reported a strategy for developing AAP-based electrochemical biosensors on SAM-covered gold electrode. The method is based on AA-triggered “outer-sphere to inner-sphere” electrochemical–chemical–chemical (ECC) redox cycling with ferrocenecarboxylic acid (FcA) as the redox mediator. Specifically, AA produced from AAP facilitated the regeneration of FcA from its electrochemical-oxidation product (referred to as FcA+ in the text), leading to an increase in the anodic current of FcA. Electrochemically inert tris(2-carboxyethyl)phosphine (TCEP) was used as a chemical reducing reagent to regenerate AA from its oxidation product, thus amplifying the electrochemical signal. The applications and performances of the proposed method were demonstrated in the competitive assays of β-amyloid (Aβ) peptides. The theoretical simplicity and high sensitivity indicated that our work would be valuable for developing simple and sensitive electrochemical biosensors.

Schizophyllum commune (SC) is widely consumed by Chinese, especially in southern part of China. The aim of the present study was to assess the extract of SC on vascular tone and the mechanisms involved. Experiments were performed on aorta of 18-week-old male Sprague-Dawley rats. Dried SC was extracted with 50% ethanol, 90% ethanol and deionized water, respectively. The effects of SC on the isometric tension of rat aortic rings were measured. Protein expression for the endothelial nitric oxide synthase (eNOS) was also determined in the primarily cultured rat aortic arterial endothelial cells (RAECs). The results showed that the water extract of SC induced a marked relaxation in aortic rings with or without endothelium. After the pretreatments of N(ω)-nitro-l-arginine methyl ester, indomethacin, RP-cAMP, and methylene blue, the SC-induced relaxation was significantly decreased. In addition, the contraction due to Ca(2+) influx and intracellular Ca(2+) release was also inhibited by SC. Furthermore, expression of the eNOS protein was significantly elevated in RAECs after treatment of SC. In conclusion, the water extract of SC induces an endothelium-dependent and -independent relaxation in rat aorta. The relaxing effect of SC involves the modulation of NO-cGMP-dependent pathways, PGI2-cAMP-depedent pathways, Ca(2+) influx though calcium channels and intracellular Ca(2+) release.

Branched polyethylenimine (PEI) was covalently linked to graphene oxide (GO) pre-modified on glassy carbon (GC) electrode (PEI/GO/GC) via an amide bond with 1-ethyl-3-[3-dimethylaminopropyl]carbodiimide/N-hydroxysulfosuccinimide (EDC/NHS) chemistry, and gold nanoparticles was then assembled on the surface of the PEI/GO/GC electrode (Au-PEI/GO/GC) by the electro-reduction of absorbed AuCl4− through electrostatic interaction. The Au-PEI/GO/GC electrode exhibited high electrocatalytic activity toward nitrite oxidation and hydrogen peroxide (H2O2) reduction. The analytical performances of the Au-PEI/GO/GC electrode demonstrated low detection limit, wider linear range, and good stability for the determination of nitrite and H2O2, which make it a promising candidate for amperometric nitrite or enzymeless H2O2 sensor.

In order to control the conductivity and oxygen functional groups in GO, GO modified glassy carbon (GC) electrodes were pretreated by electrochemical reduction at different potential and were investigated by Raman spectroscopy. The resulting GO/GC electrodes were presented for the electroanalysis of catechol (CC), hydroquinone (HQ), and L -methionine ( L -Met). It was found that simultaneous determination of the dihydroxybenzene isomers could be achieved and the over-potential of L -Met was significantly decreased at the as-prepared GO/GC electrodes. In addition, GO/GC electrodes pretreated at different potential exhibited various electro-catalytic activities. The role of conductivity and residual oxygen-containing functional groups on the electro-catalytic activity was discussed. The results shows that sometimes neither GO nor completely reduced GO demonstrates the best properties in electroanalysis. The optimal conditions can be obtained by electro-reduction at different potential.

In the present paper, we demonstrated a facile one-step and effective electrochemical strategy to synthesize graphene/NiO nanocomposites, which represents a new type of graphene/transition metal complex heterostructure. For the electrochemical deposition at the potential range of −1.2 to 0 V, graphite oxide (GO) was electrochemically reduced to graphene, accompanied by the simultaneous formation of NiO with a nanoparticle morphology. The obtained nanocomposites were characterized by scanning electron microscopy and electrochemical techniques. It was found that a large amount of NiO nanoparticles with diameter of 100–200 nm were uniformly grown on both sides of graphene nanosheets. Electrochemical experiments indicated that the composite film had a large surface area and enhanced electron-transfer rate compared with only NiO nanoparticles, due to an efficient electrical network through NiO nanoparticles direct anchoring on the surface of graphene. Moreover, as a model, glucose and methanol were selected as small molecules to investigate the electrocatalytic properties of the nanocomposites. The results showed that an enhanced electrocatalytic performance of the nanocomposites was obtained. The nanocomposites based sensor exhibited a rapid and highly sensitive response to glucose and methanol, which might find promising applications in medical applications, biological fuel cells and food industries.

p-Aminophenol (p-AP) redox cycling using chemical reductants is one strategy for developing sensitive electrochemical sensors. However, most of the reported reductants are only used on indium-tin oxide (ITO) electrodes but not gold electrodes due to the high background current caused by the oxidation reaction of the reductants on the highly electrocatalytic gold electrodes. Therefore, new strategies and/or reductants are in demand for expanding the application of p-AP redox cycling on gold electrodes. In this work, we compared the performances of several reductants in p-AP redox cycling on self-assembled monolayers (SAMs)-modified gold electrodes. Among the tested reagents, nicotinamide adenine dinucleotide (NADH), tris(2-carboxyethyl)phosphine (TCEP) and cysteamine were demonstrated to be suitable for p-AP redox cycling on the alkanethiol-modified gold electrodes because of their low background current. The rate of chemical reaction between reductants and p-quinone imine (QI, the electrochemically oxidized product of p-AP) increases in the order of NADH

In the present study, a biosensor was prepared using the water-soluble sulfonated graphene with the aim of achieving the selective and sensitive determination of dopamine (DA) in the presence of ascorbic acid (AA) and uric acid (UA). The aromatic π–π stacking and electrostatic attraction between positively charged DA and negatively charged sulfonated graphene can accelerate the electron transfer whereas weakening AA and UA oxidation on the sulfonated graphene-modified electrode. Fourier transform infrared spectra (FTIR), energy dispersive X-ray spectroscopy (EDX), atomic force microscopy (AFM) and scanning electron microscopy (SEM) were used to characterize the successful synthesis of sulfonated graphene sheets. Differential pulse voltammetry was used for electrochemical detection, the separation of the oxidation peak potentials for AA-DA, DA-UA and UA-AA was about 227 mV, 125 mV and 352 mV, which allowed selectively determining DA. A broad linear range, low detection limit, along with good ability to suppress the background current from large excess ascorbic acid (AA) and uric acid (UA) were obtained. The as-prepared sulfonated graphene sheets exhibited superior performance over conventional negatively charged Nafion films, such as flexible film thickness, unique nanostructure, excellent anti-interference ability, high sensitivity and selectivity. The proposed method was used to detect DA in real hydrochloride injection sample, human urine and serum samples with satisfactory recovery results.

It would be interesting if a signcryption scheme in the standard model could be made certificateless. One of the interesting attempts is due to Liu et al. [Z. Liu, Y. Hu, X. Zhang, H. Ma, Certificateless signcryption scheme in the standard model, Information Sciences 180 (3) (2010) 452-464]. In this paper, we provide a cryptanalysis on this scheme by depicting two kinds of subtle public key replacement attacks against it. Our analysis reveals that it does not meet the basic requirements of confidentiality and non-repudiation.

Carbodiimide provides one of the most popular and versatile methods for the covalent attachment of proteins, nucleic acids and small-molecule organic compounds to self-assembled monolayers (SAMs). In this work, we investigated the carbodiimide-mediated amine coupling reaction on SAMs with cyclic voltammetry. The negatively charged 11-mercaptoundecanoic acid (MUA) SAMs on gold electrodes hindered access of the [Fe(CN)6]3−/4− redox probe to the electrode surface. Once the carboxyl groups of MUA were activated by carbodiimide to form O-acylisourea intermediates, the electrostatic interaction between the positively charged intermediates and the negatively charged [Fe(CN)6]3−/4− probes decreased the electron-transfer resistance, resulting in the occurrence of reduction and oxidation reactions of the probe. Hydrolysis and aminolysis of the intermediates induced the loss of the positively charged carbodiimide moieties, causing non-conductive SAMs. Moreover, when the carboxyl groups were converted to amine-reactive N-hydroxysulfosuccinimide (NHSS) ester intermediates, the negatively charged NHSS esters separated from the negatively charged [Fe(CN)6]3−/4− probes and formed a barrier for the electron transfer. The introduction of positively charged amine groups through the amine coupling reaction between an NHSS ester and ethanediamine would facilitate the electron transfer again. With this method, the activity of carbodiimide-mediated activation and acylation reactions and the stability of the resulting O-acylisourea/NHSS ester intermediates in an aqueous system were addressed. The effects of the solution pH and amine concentration on these reactions were also investigated. We believe that the results will be valuable for the immobilization of biomolecules and the fabrication of biosensors.

In this study, a new type of two-dimensional (2D) hybrid heterostructure was demonstrated by electrostatic assembling the anionic sulfonated graphene sheets (SGS) and positively charged gold nanoparticles (GNPs). In this strategy, water-dispersible sulfonated graphene dispersions were synthesized by covalently binding sulfonic acid groups in reduced graphene oxide. Then, the negative charge of SGS was strong enough to drive the formation of the 2D nanomaterials with positively charged GNPs through electrostatic interaction. Furthermore, we utilized the as-prepared GNPs/SGS nanocomposites as the electrochemical enhanced material for H2O2 sensing (as the model analyte). The GNPs/SGS-modified glassy carbon electrode showed improved electrochemical catalytic ability toward electrochemical reaction of H2O2, and thus a rapid response, wide linear range and low detection limit were obtained using the chronoamperometry technique. This work might find promising applications in developing a new type of enzymeless biosensor.

In this paper, the role of the plasma membrane (PM) H + -ATPase in extracellular calmodulin (CaM)-promoted pollen germination and in tube growth of Arabidopsis thaliana was investigated. Pollen germination, pollen tube growth rate, free cytosolic Ca 2+ concentration ([Ca 2+ ] cyt ) and Ca 2+ channel activity in the PM of pollen cells were measured. In response to fusicoccin or CaM treatment, in vitro pollen germination and pollen tube growth rate, [Ca 2+ ] cyt and activity of a hyperpolarization-activated Ca 2+ -permeable channel increased. Sodium vanadate inhibited the promotion of these parameters by extracellular CaM. The results suggest that H + -ATPase may be involved in extracellular CaM-regulated pollen germination and in tube growth by modulation of the hyperpolarization-activated Ca 2+ channel in the PM of A. thaliana pollen cells.

A narrow leaf mutant was obtained after T-DNA transformation conducted on a rice variety Zhonghua 11. Several abnormal morphological characteristics, including semi-dwarf, delayed flowering time, narrow and inward rolling leaves, and lower seed-setting, were observed. The rate of net photosynthesis (under saturate light) of flag leaves in the mutant was significantly lower than that of the wild type. Moreover, the leaf transpiration rate and stomatal conductance in the mutant flag leaf were lower than those of the wild type at the grain filling stage. It was found that the mutant phenotype was not caused by the T-DNA insertion. Genetic analysis showed that the mutant was controlled by a single recessive gene, designated as nal3(t). A genetic linkage map was constructed using a large F2 mapping population derived from a cross between nal3(t) and an indica variety Longtefu B with 6 polymorphic markers on chromosome 12 identified from 366 SSR markers by the BAS method. Gene nal3(t) was mapped between the markers RM7018 and RM3331. Fine mapping of nal3(t) locus was conducted with 22 newly developed STS markers based on the sequence diversity around the region harboring nal3(t) between Nipponbare and 93–11, and nal3(t) was finally mapped to a 136-kb region between the STS markers NS10 and RH12-8.

Simultaneous determination of o-, m-, and p-dihydroxybenzene isomers were investigated by voltammetry based on the single-wall carbon nanotube (SWNT) electrode. The SWNT electrode exhibited strong and stable recognition ability toward dihydroxybenzene isomers. The oxidation peak potential difference between hydroquinone and catechol was 111 mV, catechol and resorcinol 399 mV, which indicated that the o-, m- and p-dihydroxybenzene could be identify entirely at the SWNT electrode. The peak currents of dihydroxybenzene isomers increased linearly with increasing the dihydroxybenzene isomer contents. The proposed method can be applied to simultaneous determination of dihydroxybenzene isomers.

The catecholamine release-inhibitory peptide catestatin is an endogenous nicotinic cholinergic antagonist that can inhibit secretion of catecholamine from chromaffin cells and adrenergic neurons. Therefore it can inhibit sympathetic nerve activity. Previous studies have shown that catestatin have a