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To search for more high-performance crystalline proton conducting materials and to accelerate the related research progress, in this paper, a one-dimensional coordination polymer (CP), [Co(BBOT) 2 (H 2 O) 3 ·2H 2 O] n (1) (H 2 BBOT = N-benzoyl-N′-(4-benzoxy)thiourea) was firstly prepared by solvent volatilization approach. Subsequently, the thermal, H 2 O and chemical stabilities of the CP were tested and its high structural stability was confirmed. Furthermore, in 1 , a stable solid three-dimensional framework can be constructed by intermolecular H-bonds and stacking interactions between phenyl units. Then, utilizing the AC impedance determination, the dependence of the proton conductivity of this CP on temperature and humidity in the water vapor environment was explored and the positive correlation was verified. Excitingly, the optimized proton conductivity of this compound under specific test conditions (100 °C/98 % relative humidity) can be as high as 10−4 S/cm, being in the forefront of similar crystalline solid materials. Finally, according to the value of activation energy and the characteristics of crystal structure, we speculate on the proton conduction mechanism. Proton conductivity of a CP under variable humidity and temperatures was explored. Its highest proton conductivity can attain up to 10−4 S/cm, and its proton-conduction mechanism was speculated. [Display omitted] • One carboxylate-based Co(II) coordination polymer was prepared. • Its structure was characterized by single-crystal X-ray diffraction. • Its water-assisted proton conduction was explored. • The proton-conducting mechanism was speculated. [ABSTRACT FROM AUTHOR]

We study the following Brezis–Nirenberg problem of Kirchhoff type { − ( a + b ∫ Ω | ∇ u | 2 d x ) Δ u = λ | u | q − 2 u + δ | u | 2 u , in Ω , u = 0 , on ∂ Ω , where Ω ⊂ R 4 is a bounded domain with the smooth boundary ∂Ω, 2 ≤ q < 4 and a , b , λ , δ are positive parameters. We obtain some new existence and nonexistence results, depending on the values of the above parameters, which improve some known results. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we consider the following Schrödinger–Poisson system where potentials , ( , ), and is asymptotically linear at infinity. Working in a variational setting, we prove the existence and multiplicity of solutions for the system when λ is small and belong to different ranges. We also study the boundedness of the set of the solutions found, as , in the spirit of Ruiz (2006) [21]. [Copyright &y& Elsevier]

In this paper, we investigate the following Kirchhoff type problem: ( P α , β ) { ( α ∫ R N ( | ∇ u | 2 + u 2 ) d x + β ) ( − Δ u + u ) = | u | p − 2 u in R N , u ∈ H 1 ( R N ) , where N ≥ 1 , 2 < p < 2 ⁎ ( 2 ⁎ = 2 N / ( N − 2 ) if N ≥ 3 , 2 ⁎ = ∞ if N = 1 , 2 ) and α , β are two positive parameters. By studying the decomposition of the Nehari manifold to ( P α , β ) and using the scaling technique, we give a total description on the positive solutions to ( P α , β ) . We also make an observation on the sign-changing solutions to ( P α , β ) in the current paper. [ABSTRACT FROM AUTHOR]

Abstract: Alloyed Pt m Ag nanostructures (m being the atomic Pt/Ag ratio, m =0.03–1.0) supported on carbon black were prepared and comprehensively characterized by ultraviolet–visible spectroscopy, X-ray diffraction, and transmission electron microscopy techniques. Cyclic voltammetry (CV) and chronoamperometry studies of methanol electro-oxidation reaction (MOR) in alkaline electrolyte indicated that the catalytic activity and CO tolerance of Pt were improved remarkably by the co-presence of Ag. A volcano relationship between the activity and m was found for the Pt m Ag/C catalysts, and both the highest mass-specific activity and the highest intrinsic activity of Pt were reached at m =0.5. Interestingly, we also found that the catalytic activity of the Pt m Ag/C catalysts strongly depended on the high-potential limit of CV. When the Pt m Ag/C catalysts were cycled up to 0.5V (vs. saturated calomel electrode), which induced a significant redox process of Ag, they showed ca. 50 times higher catalytic activity than those not subjected to the Ag redox process (up to 0.1V). Our study clearly demonstrated that the Ag oxide played a crucial role in promoting the catalytic role of Pt for MOR in alkaline electrolyte. [Copyright &y& Elsevier]

The activation of P2×4R activates microglia, opens the ion channels on the cell membrane (mainly calcium influx), activates intracellular related signal pathways in microglia (such as AKT, JNK), releases various injurious factors (such as TNF-a, IL-18, IL-10), induces and promotes nerve cell damage (such as neurons, astrocytes), and causes pain. While the application of P2 × 4 receptor-related antagonists (such as 5-BDBD and NP-1815-PX) can inhibit the activity of P2 × 4R, reduce its over-expression, decrease the release of injury factors, and relieve pain. Neuropathic pain (NPP) is a common symptom of most diseases in clinic, which seriously affects the mental health of patients and brings certain pain to patients. Due to its pathological mechanism is very complicated, and thus, its treatment has been one of the challenges in the field of medicine. Therefore, exploring the pathogenesis and treatment approach of NPP has aroused the interest of many researchers. ATP is an important energy information substance, which participates in the signal transmission in the body. The P2 × 4 receptor (P2 × 4R) is dependent on ATP ligand-gated cationic channel receptor, which can be activated by ATP and plays an important role in the transmission of information in the nervous system and the formation of pain. In this paper, we provide a comprehensive review of the structure and function of the P2 × 4R gene. We also discuss the pathogenesis of NPP and the intrinsic relationship between P2 × 4R and NPP. Moreover, we explore the pharmacological properties of P2 × 4R antagonists or inhibitors used as targeted therapies for NPP. [ABSTRACT FROM AUTHOR]

To detect pathogenic Yersinia enterocolitica in meat, a lateral flow immunochromatographic strip targeting on virulence gene ail was developed, which was based on recombinase polymerase amplification (RPA) and quantum dot nanobeads (QDNBs). Under optimal conditions, the minimum detection limit of the strip was 9.6 × 103 CFU/mL, with a standard curve equation of y = 0.144x - 0.5098 (R2 = 0.9863), and the detection times including the RPA reaction at hand temperature (35–36.5 °C), could be controlled in 10 min. When testing spiked sample, the recoveries (%) of Yersinia enterocolitica at 9.6 × 104 CFU/mL were 44.27 ± 2.08 and 45.31 ± 3.12 in beef and pork samples and was 107.55 ± 1.30 in chicken samples. When testing 15 actual samples, only one pork sample was tested positive, consistent with polymerase chain reaction (PCR) results. The strips are body temperature-triggered and rapidly visualized, suitable for rapid field detection of pathogenic Yersinia enterocolitica. [Display omitted] • An immunochromatographic strip was developed to detect Yersinia enterocolitica. • Using antibody conjugated quantum dot nanobeads as fluorescence reporters. • The genome was amplified by recombinase polymerase amplification. • The LOD was 9.6 × 103 CFU/mL with y = 0.144x - 0.5098 (R2 = 0.9863). [ABSTRACT FROM AUTHOR]

Abstract Ga 2 O 3 is a promising candidate for high power, high voltage devices. In this work, the band structure of the pure β -Ga 2 O 3 and the impact of orbital coupling on the Mn doped β -Ga 2 O 3 electronic structure are analyzed based on density functional theory. The Mn dopant induces impurity bands near the band edge, resulting in the decrease of the band gap of the Ga 2 O 3. When the Mn dopants only substitute the octahedrally coordinated Ga atoms, the doped systems possess the most stable structure and the ferromagnetism, the Monte Carlo simulation predicts that the Curie temperature is 421 K. The room temperature ferromagnetism can be ascribed to the strong p - d coupling and the delocalization of O-2 p orbital. The oxygen vacancy and gallium vacancy can induce the deep donor level and acceptor level into the band gap, respectively. Due to the valence change of Mn dopant, the Mn dopant undergoes a transition from donor to acceptor when the substrate obtains more carriers. Our results not only explain the observed electronic and magnetic properties in experiment, but also provide a theoretical model for designing high performance Ga 2 O 3 based devices. Highlights • The impurity bands introduced by Mn dopant can reduce the band gap of β -Ga 2 O 3. • The Monte Carlo simulation predicts that the Curie temperature is 412 K due to the p - d coupling in Mn doped Ga 2 O 3. • The Mn dopant, Ga vacancy and O vacancy can modulate the conductivity of the Ga 2 O 3. [ABSTRACT FROM AUTHOR]

Abstract: Egg allergy is an important public health and safety concern, so quantification and administration of food or vaccines containing ovalbumin (OVA) are urgently needed. This study aimed to establish a rapid and sensitive magnetic particles–chemiluminescence enzyme immunoassay (MPs–CLEIA) for the determination of OVA. The proposed method was developed on the basis of a double antibodies sandwich immunoreaction and luminol–H2O2 chemiluminescence system. The MPs served as both the solid phase and separator, the anti-OVA MPs-coated polyclonal antibodies (pAbs) were used as capturing antibody, and the horseradish peroxidase (HRP)-labeled monoclonal antibody (mAb) was taken as detecting antibody. The parameters of the method were evaluated and optimized. The established MPs–CLEIA method had a linear range from 0.31 to 100ng/ml with a detection limit of 0.24ng/ml. The assays showed low reactivities and less than 5% of intraassay and interassay coefficients of variation (CVs), and the average recoveries were between 92 and 97%. Furthermore, the developed method was applied in real samples analysis successfully, and the correlation coefficient with the commercially available OVA kit was 0.9976. Moreover, it was more rapid and sensitive compared with the other methods for testing OVA. [Copyright &y& Elsevier]

Abstract: A lateral flow immunochromatographic (LFIC) test strip based on a colloidal gold–monoclonal antibody (McAb) conjugate was developed for on-site rapid detection of okadaic acid (OA) in shellfish. It applies a competitive format using an immobilized toxin conjugate and free toxin present in samples. The McAb against OA was conjugated with 20-nm colloidal gold as detector reagent. The toxin in the sample competed with the immobilized toxin to bind to the gold conjugated with McAb. The colloidal gold/McAb/toxin mobile complex was not captured by OA–bovine serum albumin (BSA) on the test line, but it was captured by goat anti-mouse immunoglobulin G (IgG) on the control line. The color density of the test line correlated with the concentration of toxin in the range of 10–50ngml−1. The qualitative detection limit of 150μgkg−1 sample was close to the European Union (EU) regulatory limit (160μgkg−1). Therefore, these strips were able to directly and qualitatively estimate the consuming safety of shellfish. They require no equipment because of available visual results, and they screened numerous samples within 10min. The results were further confirmed by high-performance liquid chromatography tandem mass spectrometry (HPLC–MS/MS). As a food safety screening tool, the test strips are convenient and useful to rapidly on-site test the presence of OA in shellfish products. [Copyright &y& Elsevier]

Abstract: Glioma is a highly invasive, rapidly spreading form of brain cancer that is resistant to surgical and medical treatment. The recent progresses made in intracellular and ion channels of glioma cells provide a potential new approach for biochemical therapy of brain tumor. In this paper, we reviewed clinical data on chemotherapy by temozolomide and results from new studies on voltage-gated potassium channels, large-conductance Ca2+-activated K+ channels, volume-activated chloride channels, glioma-specific chloride channel and their modulators. These new findings may represent future directions for brain tumor studies and treatment. [Copyright &y& Elsevier]

New myricetin-pentadienone hybrids with anti-inflammatory was discovered which could significantly decreased production of NO, IL-6 and TNF-α LPS-stimulated. Preliminary mechanism indicated that it could inhibit thioredoxin reductase expression, resulting in inhibiting of cell signaling pathway. • New myricetin-pentadienone hybrids were synthesized. • Compounds showed anti-inflammatory activity against IL-6、NO and TNF-α. • Preliminary mechanisms of anti-inflammatory action were discovered. Some important pro-inflammatory cytokines such as interleukin-6, tumor necrosis factor-α and nitric oxide are thought to play key roles in the destruction of cartilage and bone tissue in joints affected by rheumatoid arthritis. In the present study, a series of new myricetin-pentadienone hybrids were designed and synthesized. Majority of them effectively inhibited the expressions liposaccharide-induced secretion of IL-6, TNF-α and NO in RAW264.7. The most prominent compound 5o could significantly decrease production of above inflammatory factors with IC 50 values of 5.22 µM, 8.22 µM and 9.31 µM, respectively. Preliminary mechanism studies indicated that it could inhibit the expression of thioredoxin reductase, resulting in inhibiting of cell signaling pathway nuclear factor (N-κB) and mitogen-activated protein kinases. Significantly, compound 5o was found to effectively inhibit Freund's complete adjuvant induced rat adjuvant arthritis in vivo. [ABSTRACT FROM AUTHOR]