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As simple and ubiquitous redox-active organic molecules, quinones participate in diverse electron transfer processes in chemistry and biological systems for energy transformation and signal transduction. We introduce here a practical exercise to study the redox potentials of benzoquinone and its two derivatives by combining the electrochemistry method with quantum chemistry computation. The practical reduction potentials of three quinones were measured by cyclic voltammetry experiment. Quantum chemistry computation, on the other hand, provided theoretical Gibbs free energy change and reduction potentials of the three quinones, which were found to be in line with the experimental results. Detailed thermodynamic energy analysis based on the computation results revealed that the reduction Gibbs free energy changes of the three quinones were mainly contributed from the electronic energies change of the molecules, while thermal energy and entropy played a relatively minor role. The energy levels of the lowest unoccupied molecular orbital (LUMO) of the three quinones, which were modulated by substituent groups and conjugation structures, were further identified as the main origin of the reduction potential. This experiment provides practical and theoretical training on the fundamental ideas involved in major courses like thermodynamics, quantum chemistry, electrochemistry, and organic chemistry, and promotes students to find the tie between macroscopic redox properties of chemicals and their microscopic molecular structures, a key topic in chemistry education.

Photochemistry to prepare platinum nanoparticles (Pt NPs) is an essential way to control Pt NPs catalyst size distribution. This article reports a series of morphologically controlled syntheses of Pt NPs loaded on modified carbon nanotube (Pt-CNTs). In the synthesis, Polyethylene glycol (PEG) participates in reactions both as a reducing agent and a stabilizer. Visible light irradiation was adopted as a kinetic controlling approach. Typical 4-nitrophenol (4-NP) reduction was adopted to probe the catalytic performances. Characterizations prove that visible light irradiation is an effective way to control the reaction process. In the optimized reaction conditions, i.e., when the ratio PEG:H2O is 1:9, and the pH is 10, the as-prepared Pt NPs are consequently in a very narrow sized distribution with an average diameter of 1.29 nm. The Pt-CNTs present a high reaction rate constant of 0.624 min-1 in the catalytic reduction of 4-NP. All the research results are beneficial for exploring more green chemistry and facile photochemical approaches in the controlled preparation of Pt nanocatalysts.

The Al-Si-Cu-Mg-Ni alloy is a commonly used piston alloy. In this work, different amounts of phosphorus modifier and Al-2P (Al-2%P) master alloy modifier were added to the original alloy. The ultra...

In this work, we report a family of co-halogenated two-dimensional hybrid perovskites (2DHPs) based on phenethylammonium lead halogen ((PEA)2Pb(Cl/Br)4) in which the organic cation-site (PEA) is substituted with halogen at the para-site, namely the formation of 4-halophenethylamine (X-p-PEA) (X = Cl, Br; p: para-site). The organic cations are regulated by introducing halogen ions at the para-site of the benzene ring to promote the structural distortion of the lead halide octahedral inorganic layer. Furthermore, (X-p-PEA) causes a shift in the energy band distribution of 2DHPs. In this case, the photoluminescence competition of free excitons (FEs) and self-trapped excitons (STEs) changes the microscopic relaxation process of excitons. In addition, we found that (Br-p-PEA) can increase the photoluminescence quantum yield (PLQY). At the same time, we regulate the halogen-site of perovskites from lead-chloride perovskites (LCPs) to lead bromine perovskites (LBPs), achieving emission from white light to blue light. Therefore, the co-halogenation regulation strategy of organic cation-site and halogen-site can effectively regulate the photoluminescence wavelength and improve the PLQY. This is of great significance for the development of perovskite materials with specific optoelectronic applications.

Nitrile-functionalized anticancer drugs have drawn wide attention. However, the water solubility and side-effects of the drugs reduce their effectiveness in cancer therapy. In this paper, three novel para-, meta- and ortho-linked nitrile-containing water solubility copper(II) porphyrin complexes have been synthesized. Then the relationship between the structure and anticancer performance of the three complexes were investigated. When the complexes have an effect on the cancer cells (A549, H1975, HepG2 and T47D) and normal cell (Hs578 Bst), they demonstrate effective anticancer activity and biocompatibility; the para-nitrile functionalized complex p-CuP can selectively act on H1975 cells, with the lowest IC50 (6.09 μM); the anticancer effect of water-soluble porphyrin ligands (p-L, m-L and o-L) is augmented by coordinate to copper ion(II). Furthermore, DNA binding and flow cytometry methods were applied to research their mechanism, and the results show that these complexes could intercalate DNA and the effect of p-CuP is the best, so there is DNA binding in the anticancer mechanism, also accompanied by mitochondrial dysfunction and arresting cell cycle. In addition, Density Functional Theory (DFT) calculation analyses were carried out for the cationic porphyrin ligands and complexes, using the method with a B3LYP level of theory with the 6-31G(d) and LanL2DZ basis sets, which further proved the biological activities of the target compounds.

Ferulic acid and its derivative γ-oryzanol are common in Rice. They have the same molecular skeleton with some sunscreens that used commonly, but there were no reports on them as rice UV protection. In this work, UV absorption and fluorescence emission spectrum are performed to measure ferulic acid and γ-oryzanol effect of fighting with ultraviolet irradiation. We demonstrated that both ferulic acid and γ-oryzanol have good absorption intensity at UVA, UVB and UVC regions, with superior photostability. Furthermore, the optimized molecular conformation and potential energy surfaces (PES) in ground and excited states are obtained by using the time-dependent density functional theory (TD-DFT) method. From the calculation results, it can conclude that their S1 states decay to the S0 state via internal conversion (IC) process at the S1/S0 conical intersection (CI) point of PES followed by trans–cis photoisomerization. For the first time, we elucidated the mechanism of UV protection for ferulic acid and γ-oryzanol as UV protection in rice from our excited state non-adiabatic dynamics.

Numerous studies have shown that the inhaled general anesthetic sevoflurane imposes toxicity on the central nervous system during the developmental period but the underlying mechanisms remain unclear. Neuropeptide Y (NPY) was reported to have important neuroprotective effects, which can attenuate neuronal loss under pathological conditions. However, the effects of NPY on sevoflurane-induced hippocampal neuronal apoptosis have not been investigated. In this study, postnatal day 7 (PND7) Sprague-Dawley rats and primary cultured cells separated from hippocampi were exposed to sevoflurane (2.4% for 4 h) and the NPY expression levels after treatment were analyzed. Furthermore, neuronal apoptosis assay was conducted via immunofluorescence staining of cleaved caspase-3 and flow cytometry after exogenous NPY administration to PND7 rats as well as cultured hippocampal neurons to elucidate the role of NPY in sevoflurane-induced neurotoxicity. Our results showed the level of NPY gradually decreased within 24 h after sevoflurane exposure in both the hippocampus of PND7 rats and cultured hippocampal neurons, but not in cultured astrocytes. In the exogenous NPY pretreatment study, the proportion of cleaved caspase-3 positive cells in the CA1 region of the hippocampus was increased significantly at 24 h after sevoflurane treatment, while NPY pretreatment could reduce it. Similarly, NPY could also reverse the apoptogenic effect of sevoflurane on cultured neurons. Herein, our results showed that sevoflurane caused a significant decrease in NPY expression, whereas exogenous NPY supplementation could reduce sevoflurane-induced hippocampal neuronal apoptosis both in vivo and in vitro.

In this work, the electronic excited states of hypoxanthine in solution such as water and acetonitrile are investigated by the time-dependent density functional theory (TDDFT) method. We demonstrated for the first time that the intermolecular excited-state electron transfer (ESET) from solvents to the hypoxanthine through excited-state intermolecular hydrogen-bonds cluster exhibits obvious site-selectivity. Excited-state electron transfer could only occur at the N7 site of hypoxanthine molecule in water solution, while that is the N9 site in acetonitrile. Potential energy surfaces for different electronic states of hypoxanthine with and without the influence of the excited-state hydrogen bonding cluster are also discussed. Site-selective ESET is proposed to induce the internal conversion of hypoxanthine from S2 state to S1 at a conical intersection, which is responsible for the ultrashort lifetime of hypoxanthine in excited state in solution. These results pave a novel way to understand the photophysical and photochemical behaviors of DNA bases and their derivatives in solution phase.

Attapulgite (ATP) and its organically modified products have been investigated for potential applications in environmental remediation. In this work, a variety of modifiers with different functional groups, including saturated sodium chloride solution (NaCl), cetyltrimethyl ammonium bromide (CTAB) and humic acid (HA), were used to treat attapulgite clay firstly, and then with the modified ATP as adsorbent and acrylamide (AAm) as monomer, polyacrylamide/modified attapulgite (PAAm/modified ATP) composite hydrogel which could adsorb heavy metal ions Ni(II) and organic pollutants phenol were synthesized. The structure of the raw ATP and modified ATP was specified with Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and Transmission electron microscope (TEM). The experiments indicated that the modified ATP and composite hydrogel possessed good adsorption properties for Ni(II) ions and phenol. The adsorption capacity of PAAm/HA-ATP hydrogel for Ni(II) was as high as 64.3 mg/g, which was 194.9% of pure hydrogel. The adsorption isotherm of HA-modified ATP (HA-ATP) and adsorption kinetics of PAAm/HA-ATP composite hydrogel was particularly concerned. The adsorption isotherm equation fitted well on the Langmuir model and R

In this study, Ag and Cu2O nanoparticles modified flower-like ZnO nanostructures have been successfully synthesized by stepwise method, and the photocatalytic properties were investigated in detail. High-resolution transmission electron microscopy, X-ray diffractions analysis, X-ray photoelectron spectroscopy and scanning electron microscopy were used to analyze the samples. Meanwhile, the derived nanoparticles’ structured and morphologic characters were analyzed by Brunauer–Emmett–Teller. The results have shown that the 3D flower-like ZnO microspheres were composed of 2D ZnO nanosheets decorated Ag and Cu2O and exhibiting flower-like Ag@Cu2O/ZnO architectures. We studied the optical absorption (UV–vis) as well as emission (PL) characters of the specimen and the outcomes suggested more superior photocatalytic characteristics for cuprous oxide and silver co-doped zinc oxide sample compared to other samples. Electron Paramagnetic Resonance test results show that there are mainly ⋅ O 2 − , h + and O H • free radicals in the process of CR degradation. A Radical-trapping test indicated that of ⋅ O 2 − and h + was more effective than O H • in the degradation of CR.

PVDF-g-PAA-CDs composite membrane with stable fluorescence was prepared by grafting carbon dots (CDs) onto the surface of PVDF-g-PAA membrane through amidation reaction for the first time. The results of Transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and fluorescence properties clearly showed the formation of CDs with a strong blue fluorescence under UV light, which was ascribed to the influence of surface functional groups or edge defects. The effect of CDs on the surface composition, morphology, hydrophilicity and pure water flux of PVDF-g-PAA-CDs composite membranes was investigated. Consistent with CDs, PVDF-g-PAA-CD composite membrane also exhibits photoluminescence behavior that is dependent on excitation. The addition of CDs gives the composite membrane a significant fluorescence quenching effect on Cu2+, Hg2+ and Fe3+ without being affected by K+, Na+, Cl−. This may be because the complexation of Cu2+, Hg2+ and Fe3+ with coordination bonds such as -NH2 and -COOH on CDs surface can accelerate the extinction of electron/hole non-radiative recombination through effective electron or energy transfer, leading to fluorescence quenching of CDs on the surface of PVDF-g-PAA-CD composite membrane. Furthermore, the optical detection limit of the respective metal ion is found to be 1 nmol/L for Cu2+ and Hg2+ and 1 μmol/L for Fe3+ by studying the changes in fluorescence spectra of PVDF-g-PAA-CD composite membrane. In summary, PVDF-g-PAA-CDs fluorescent composite membrane has the advantages of fast, stable, environmentally friendly, simple, and inexpensive as a solid platform for heavy metal ion detection, and has great potential in the field of water purification.

Background: N6-Methyladenosine (m6A) methylation is the most prevalent internal posttranscriptional modification on mammalian mRNA. But its role in neuromyelitis optica spectrum disorders (NMOSD) is not known.Aims: To explore the mechanism of m6A in NMOSD patients.Methods: This study assessed the m6A methylation levels in blood from two groups: NMOSD patients and healthy controls. Methylated RNA immunoprecipitation Sequencing (MeRIP-seq) and RNA-seq were performed to assess differences in m6A methylation between NMOSD patients and healthy controls. Ultra-high performance liquid chromatography coupled with triple quadruple mass spectrometry (UPLC-QQQ-MS) method was performed to check m6A level. Differential m6A methylation genes were validated by MeRIP-qPCR.Results: Compared with that in the control group, the total m6A level was decreased in the NMOSD group. Genes with upregulated methylation were primarily enriched in processes associated with RNA splicing, mRNA processing, and innate immune response, while genes with downregulated methylation were enriched in processes associated with the regulation of transcription, DNA-templating, and the positive regulation of I-kappa B kinase/NF-kappa B signalling.Conclusion: These findings demonstrate that differential m6A methylation may act on functional genes to regulate immune homeostasis in NMOSD.

1. The influence of glucose oxidase (GOD) supplementation on growth, gut inflammation and its compensatory effects in broilers was investigated before and after heat stress.2. Before heat stress, one-day-old broilers were divided into two groups: the control (CON) and GOD (100 g/t complete feed) groups. On d 21, the CON group was equally divided into CON1 and CON2 groups, and heat stress (35°C) was applied to the CON2 and GOD groups for 8 h/day to the end of the study, d 27 of age. The chickens were either killed before heat stress and 2 d after heat stress for the determination of cytokines in the liver and ileum, serum antioxidant enzymes and ileal microbiota. Growth performance was determined before and 7 d after heat stress.3. The GOD decreased Clostridiales and Enterobacteriaceae families of bacteria and increased ileal nuclear factor-κB, interleukin-1β, and interferon-γ (P

This paper presents the visible light-assisted synthesis of surfactant-free Pt nanoparticles (Pt-NPs) supported on multi-walled carbon nanotubes (MWCNTs) at ambient condition. Transmission electron microscopy (TEM) images indicate that Pt-NPs with high density and relative small in size (about 2 nm) were monodispersed on the surface of MWCNTs. The characterizations of Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), X-ray diffractometer (XRD) and ultraviolet–visible spectroscopy (UV–Vis) prove that visible light irradiation significantly affect the species distribution of [PtCl4]2− precursor in the hydrolysis and then promote hydrolysate Pt oxides loading on MWCNTs. The loading process decides the morphology of Pt-NPs rather than the following precursor reduction, which does not change the morphology but only the valance state of platinum. The catalytic activity of Pt/MWCNTs was tested in subsequent methanol electrochemical reactions and 4-nitrophenol (4-NP) reduction.

To fabricate hydrophilic and anti-fouling PVDF ultrafiltration membrane, a kind of tailor-made symmetrical amphiphilic triblock copolymer, polyacryloylmorpholine-b-poly (methyl methacrylate)-b-polyacryloylmorpholine (PACMO-b-PMMA-b-PACMO, termed as PAMA), was prepared via RAFT polymerization and employed as an in situ surface segregation modifier. FTIR, 1H NMR, and GPC were used to verify the well-defined chemical structure of PAMA. The hydrophilic PACMO segments of PAMA were enriched on the surface of membrane skin and interior pores as confirmed by ATR-FTIR, XPS, EDX, and water contact angle tests, endowing the blend membranes with outstanding hydrophilicity. The different cross-sectional and surface morphologies of the PVDF/PAMA blend membranes indicated that the introduction of PAMA modifiers could manipulate membrane structure due to their strong pore-forming ability. Compared with the pure PVDF membrane, PVDF/PAMA blend membranes showed higher permeability for water (28.1 times higher), excellent rejection for bovine serum albumin (up to 98.3%), and enhanced fouling resistance with a higher flux recovery ratio (up to 98.1%). Therefore, the approach of in situ surface segregation employed the RAFT mediated well-defined amphiphilic PAMA triblock copolymer modifiers for the preparation of anti-fouling PVDF membranes showed a great potential in water purification.

A novel near-infrared-emitting aza-BODIPY-based fluorescent probe with two tellurium atoms at two upper benzyl rings has been prepared and explored for its fluorescent sensing properties towards hypochlorous acid/hypochorite (HClO/ClO−), which showed high selectivity and absolutely fluorescent “turn-on” phenomenon at 738 nm. The fluorescence of this probe was sufficiently quenched due to photoindued electron transfer by two tellurium atoms. Upon exposure to HClO/ClO−, a strong near-infrared emission at 738 nm appeared with fluorescence quantum yields changing from 0 to 0.11. This remarkable fluorescence change was ascribed to the oxidation of both electron-rich tellurium atoms. The detection limit of this probe towards HClO/ClO− was calculated to 0.09 μM in acetonitrile aqueous solution by the linear fluorescence change at 738 nm in the HClO/ClO−-concentration range of 0–30 μM. Interestingly, this probe was found to be applicable in a broad pH range (2–10). Meanwhile, the oxidized probe could be further responsive to biothiols with substantial fluorescence disappearance. The bioimaging experiments in RAW264.7 cells showed the appearance of intracellular near-infrared fluorescence after addition of HClO/ClO− and PMA, and the fluorescence could also be reversed to be silenced by further introduction of GSH, confirming its potential application for exogenous and endogenous detection of HClO/ClO− in living cells.

Members of Thermococcales harbor a number of genes encoding putative aminotransferase class III enzymes. Here, we characterized the TK1211 protein from the hyperthermophilic archaeon Thermococcus kodakarensis. The TK1211 gene was expressed in T. kodakarensis under the control of the strong, constitutive promoter of the cell surface glycoprotein gene TK0895 (Pcsg). The purified protein did not display aminotransferase activity but exhibited racemase activity. An examination of most amino acids indicated that the enzyme was a racemase with relatively high activity toward Leu and Met. Kinetic analysis indicated that Leu was the most preferred substrate. A TK1211 gene disruption strain (ΔTK1211) was constructed and grown on minimal medium supplemented with l- or d-Leu or l- or d-Met. The wild-type T. kodakarensis is not able to synthesize Leu and displays Leu auxotrophy, providing a direct means to examine the Leu racemase activity of the TK1211 protein in vivo. When we replaced l-Leu with d-Leu in the medium, the host strain with an intact TK1211 gene displayed an extended lag phase but displayed cell yield similar to that observed in medium with l-Leu. In contrast, the ΔTK1211 strain displayed growth in medium with l-Leu but could not grow with d-Leu. The results indicate that TK1211 encodes a Leu racemase that is active in T. kodakarensis cells and that no other protein exhibits this activity, at least to an extent that can support growth. Growth experiments with l- or d-Met also confirmed the Met racemase activity of the TK1211 protein in T. kodakarensis. IMPORTANCE Phylogenetic analysis of aminotransferase class III proteins from all domains of life reveals numerous groups of protein sequences. One of these groups includes a large number of sequences from Thermococcales species and can be divided into four subgroups. Representatives of three of these subgroups have been characterized in detail. This study reveals that a representative from the remaining uncharacterized subgroup is an amino acid racemase with preference toward Leu and Met. Taken together with results of previous studies on enzymes from Pyrococcus horikoshii and Thermococcus kodakarensis, members of the four subgroups now can be presumed to function as a broad-substrate-specificity amino acid racemase (subgroup 1), alanine/serine racemase (subgroup 2), ornithine ω-aminotransferase (subgroup 3), or Leu/Met racemase (subgroup 4).

Background Stem cell transplantation has been reported as one of the promising strategies to treat retinal degenerative diseases. But, the application and the role of retina stem cells (RSCs) in the treatment of patients with retinal degenerative diseases have not been fully revealed. This study aimed to investigate the potential role of transplantation of the embryo-derived RSCs into the vitreous cavity in repairing the damaged retina in mice. Methods RSCs were isolated from Kunming mice E17 embryonic retina and ciliary body tissues, and labeled with 5-bromo-2’-deoxyuridin (BrdU). Retinal optic nerve crush injury was induced in left eyes in male Kunming mice by ring clamping the optic nerve. The 6th -generation of BrdU-labeled RSCs were transplanted into the damaged retina by the intravitreal injection, and saline injected eyes were used as the control. Hematoxylin and eosin histological staining, and BrdU, Nestin and Pax6 immunostaining were performed. Electroretinogram (ERG) was used for assessing the electrical activity of the retina. Results Embryo-derived RSCs were identified by the positive stains of Pax6 and Nestin. BrdU incorporation was detected in the majority of RSCs. The damaged retina showed cellular nuclear disintegration and fragmentation in the retinal tissue which progressed over the periods of clamping time, and decreased amplitudes of a and b waves in ERG. In the damaged retina with RSCs transplantation, the positive staining for BrdU, Pax6 and Nestin were revealed on the retinal surface. Notably, RSCs migrated into the retinal ganglion cell layer and inner nuclear. Transplanted RSCs significantly elevated the amplitudes of a waves in retina injured eyes. Conclusions Embryonic RSCs have similar characteristics to neural stem cells. Transplantation of RSCs by intravitreal injection would be able to repair the damaged retina.

Stimuli-response organic solid-state luminescence switching materials are attracting increasing interest due to their smart photophysical properties. In this study, a morpholine-modified naphthalic anhydride derivative, 4-(4-morpholinyl)naphthalic anhydride (MBC), was synthesized and studied. Its two crystal polymorphs, MBC-G and MBC-O, were obtained under different crystallization conditions. These two distinct crystals show significantly different solid-state luminescence behaviors: a green emission at 535 nm for MBC-G, and an orange emission at 572 nm for MBC-O. Upon fiercely grinding the MBC-G crystal or melting and then quickly cooling it, a phase transition occurs from MBC-G to MBC-O, accompanied by a fluorescence change from green to orange. The reverse transformation from MBC-O to MBC-G can be achieved by recrystallization. The X-ray single crystal structures show that the green emission should be attributed to molecular J-aggregation in the crystal packing, and the orange emission may originate from molecular H-aggregation. This switchable color nature gives MBC the promising candidate for potential smart anti-counterfeiting and light-emitting materials.

High alcohol-producing Klebsiella pneumoniae (HiAlc Kpn) in the gut microbiota had been demonstrated to be the causative agent of fatty liver disease (FLD). However, the catabolic pathways for alcohol production in vivo remain unclear. Here, we characterized the genome of HiAlc and medium alcohol-producing (MedAlc) Kpn and constructed an adh (an essential gene encoding alcohol dehydrogenase) knock-out HiAlc Kpn W14 strain (W14Δadh) using CRISPR-Cas9 system. Subsequently, we established the mouse model via gavage administration of HiAlc Kpn W14 and W14 Δadh strains, respectively. Proteome and metabolome analysis showed that 10 proteins and six major metabolites involved in the 2,3-butanediol fermentation pathway exhibited at least a three-fold change or greater during intestinal growth. Compared with HiAlc Kpn W14-fed mice, W14Δadh-fed mice with weak alcohol-producing ability did not show apparent pathological changes at 4 weeks, although some steatotic hepatocytes were observed at 12 weeks. Our data demonstrated that carbohydrate substances are catabolized to produce alcohol and 2,3-butanediol via the 2,3-butanediol fermentation pathway in HiAlc Kpn, which could be a promising clinical diagnostic marker. The production of high amounts of endogenous alcohol is responsible for the observed steatosis effects in hepatocytes in vivo.

In recent years, α-glucosidase inhibitors (AGIs) have played a significant role in the treatment of type II diabetes (T2D), so it is necessary to develop a reliable and sensitive method to find new AGIs. Herein, we establish a novel method based on fluorescent carbon nitride nanoparticles (CNNPs) for the sensitive detection of the activity of α-glucosidase (α-glu) and the screening of its inhibitors. A CNNP-based fluorescent probe is synthesized from green raw materials, urea and lysine, by a one-pot method. In the presence of α-glu, the substrate 4-nitrophenyl-α-D-glucopyranoside (pNPG) is hydrolyzed to generate 4-nitrophenol (pNP), leading to the fluorescence (FL) quenching of CNNPs due to the inner filter effect (IFE). On the other hand, the activity of α-glu is inhibited after the addition of AGIs, which turns on the FL of CNNPs. In this way, the detection of α-glu activity and the screening of AGIs are achieved. The linear range is 1.25–10.00 U L−1 with a limit of detection as low as 0.17 U L−1 and the IC50 values of two typical inhibitors (gallic acid and acarbose) are 813 μM and 465 μM, respectively. The CNNP probe is further applied for the determination of α-glu activity in human serum samples with satisfactory results.

In this work, we have first demonstrated that the potassium cation doping effect on photoluminescence (PL) regulation of CH3NH3PbBr3 (CH3NH3+=MA+) colloidal perovskite quantum dots (QDs) is significantly different from the other alkali cation doping effects. The PL intensity will be generally enhanced with the increase doping amounts of other alkali cations. Herein, we have unveiled that the PL of the potassium-doped perovskite QDs is initially prompted by the potassium ions doping and then inhibited with further growing doping amount of the potassium ions. Furthermore, we have also demonstrated that the PL inhibition phenomenon is ascribed as quick trapping of redundant photogenerated electrons by the trap states after huge amount doping besides defect passivation and octahedral structure distortion induced by the initial doping. At the same time, the specific excited state transient absorption and the lifetime of MAxK1-xPbBr3 also confirm that the radiation recombination process is enhanced via defect passivation and lattice distortion, which is induced by moderate potassium cations doping. In addition, the PL of colloidal perovskite quantum dots can be adjusted from orange to cyan within the wavelength range of 300 nm − 600 nm and exhibit better stability.

Currently, the early disease screening is still the most effective way to increase the survival rate of the HIV/HCV infected patients. However, the trace analysis remains a great challenge for early disease screening. Herein, a novel silver nanocluster (AgNCs) is in situ generated and served as fluorescence probes for the ultrasensitive HIV/HCV DNA detection by combing Exo III-assisted target recycling amplification (ERA) with rolling circle amplification (RCA). As an important key element of this sensor, the padlock probes (PLP) of RCA are exquisitely designed to compose of a guanine-rich (G-rich) region. Target DNA firstly hybridizes with the stem segment of the hairpin DNA (hp-DNA) and triggered the Exo III digestion, which releases and recycles the target and generate numerous ssDNA fragments. The generated ssDNA fragments act as ligation probes, which hybridize with PLP to trigger the RCA process, generating numerous periodically repeated cytosine-rich (C-rich) units. In the presence of NaBH4 and AgNO3, numerous AgNCs are in situ generated, thereby producing a strong fluorescent signal. Under optimal conditions, an ultrasensitive DNA machine is constructed for the detection of HIV DNA with a detection limit of 1.4 fM and a linear range of 10 fM to 100 pM. More fascinatingly, this DNA machine could intelligently distinguish multiple virus DNAs by the construction of analog AND and OR logic circuits.

Design and engineering of highly efficient emitting materials with assembly-induced luminescence, such as room-temperature phosphorescence (RTP) and aggregation-induced emission (AIE), have stimulated extensive efforts. Here, we propose a new strategy to obtain size-controlled Eu3+-complex nanoparticles (Eu-NPs) with self-assembly-induced luminescence (SAIL) characteristics without encapsulation or hybridization. Compared with previous RTP or AIE materials, the SAIL phenomena of increased luminescence intensity and lifetime in aqueous solution for the proposed Eu-NPs are due to the combined effect of self-assembly in confining the molecular motion and shielding the water quenching. As proof of concept, we also show that this system can be further applied in bioimaging, temperature measurement and HClO sensing. The SAIL activity of the rare-earth (RE) system proposed here offers a further step forward on the roadmap for the development of RE light conversion systems and their integration in bioimaging and therapy applications., In this work, a new strategy was proposed to obtain size-controlled Eu3+-complex nanoparticles (Eu-NPs) with self-assembly induced luminescence (SAIL) characteristics without encapsulation or hybridization. And the SAIL activity of the rare-earth (RE) system proposed here offers a further step forward on the roadmap for the development of RE light conversion and their integration in bioimaging and therapy applications.

Ordered mesoporous carbon (OMC) is considered to be a prospective carbon-based material for microwave absorption because of its abundant well-ordered mesoporous structures, high specific surface area, numerous active sites, and facile preparation process. However, its development has been seriously hindered by its poor impedance-matching characteristic. Herein, silica-modified OMC composites with a designable impedance-matching transition layer are successfully fabricated via a self-assembly method and succeeding calcination treatment. In addition, the silica in OMC@SiO

Natural UV photoprotection plays a vital role in physiological protection. It has been reported that UVC radiation can make resveratrol (RSV) and piceatannol (PIC) accumulate in grape skin. In this work, we demonstrated that RSV and PIC could significantly absorb UVA and UVB, and confirmed their satisfactory photostability. Furthermore, we clarified the UV photoprotection mechanism of typical stilbenoids of RSV and PIC for the first time by using combined femtosecond transient absorption (FTA) spectroscopy and time-dependent density functional theory (TD-DFT) calculations. RSV and PIC can be photoexcited to the excited state after UVA and UVB absorption. Subsequently, the photoisomerized RSV and PIC quickly relax to the ground state via nonadiabatic transition from the S1 state at a conical intersection (CI) position between potential energy surfaces (PESs) of S1 and S0 states. This ultrafast trans-cis photoisomerization will take place within a few tens of picoseconds. As a result, the UV energy absorbed by RSV and PIC could be dissipated by an ultrafast nonadiabatic photoisomerization process.

The hydrolysis of K2[PtCl4] under visible light, the equilibrium, morphology, and size of Pt NPs combined with CDs, the valence states of Pt element and the bonding of Pt NPs with CDs, the influence of different kinds of cyclodextrin (α, β, γ-CDs), the acidity of the solution, and the visible light color on the catalytic ability of Pt NPs were all researched by typical approaches. All results prove visible light irradiation is effectively playing a key role in the reaction process to form Pt NPs in a very narrow size distribution. pH = 9, β-CDs, and purple visible light are the optimized reaction conditions. The Pt-CDs present a high rate constant of 0.88 min−1 in the catalytic reduction of 4-NP. This research is beneficial for expanding photochemical approaches from ultraviolet light to visible light, which is more of green chemistry, low cost, and facile.

In this work, the modified poly (vinylidene fluoride) (PVDF) membranes provided an excellent hydrophilicity and the antifouling properties were fabricated via surface modification by 2-N-propyl sulfonated chitosan (PCS). Without sophisticated and environmentally hazardous operation, PCS was synthesized through ring-opening polymerization and immobilized onto the coated PVDF membrane surface in aqueous acetic acid solution and Tris-HCl buffer dopamine solution, respectively, while polydopamine (PDA) serving as a precursor coating layer. The modified membranes showed inferior BSA adsorption resulting from the construction of hydration layer via hydrogen bond between hydrophilic groups in PCS on membrane surface and water molecules. Due to the excellent hydrophilicity (39°) and minimal irreversible fouling (8.2%) of modified membrane, the water flux recovery rate up to 90.4% was easily attached after two cycles, which is 45% increasing of the PVDF membrane without modification. Additionally, the physic structure of PVDF membranes does not cause damage during surface modification.

This study was done to isolate novel antioxidant peptides from Chinese chestnut protein (CCP) hydrolysed with alcalase. A series of purification steps including ultrafiltration, gel filtration chromatography, anion exchange chromatography, and reverse-phase high-performance liquid chromatography were used to purify the CCP. ABTS radical scavenging capacity was assessed to evaluate antioxidant activity. Five antioxidant peptides, VYTE, TKGQ, MMLQK, TPAIS, and VSAFLA, with molecular weights of 590.20, 592.17, 745.29, 647.20, and 606.34 Da, respectively, were obtained from the most active fractions and characterized using nano-liquid chromatography electrospray ionisation-tandem mass spectrometry. VYTE and VSAFLA showed the highest ABTS radical scavenging capacity with IC50 values of 0.13 ± 0.01 and 0.28 ± 0.04 mg/mL, respectively (P

In this study, the preventative effects of Lactobacillus plantarum YS-3 (LP-YS3) on colitis were studied using an in vitro animal experiment. Oxazolone was administered to BALB/c mice to induce colitis, and the preventive effects of LP-YS3 were determined using serum- and tissue-related indexes. The mice treated with LP-YS3 showed a significant decrease (p

Poly(N-acryoyl morpholine) (PACMO), a promising antifouling surface modifier, has many desirable properties including high hydrophilicity, chemical stability, and excellent hemocompatibility. Considering the intrinsic hydrophobic property of most polymer membranes, surface modification by hydrogen bonding self-assembly has garnered intense interest. In this work, a hydrophobic poly(vinylidene fluoride) (PVDF) membrane surface was first dip-coated a polydopamine (PDA) coating and then followed by immobilization of PAMCO via hydrogen-bonded interactions between PACMO and PDA. The mechanism of foulants deposition onto the membrane surface was quantitatively assessed by extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory. The hydrophilic PACMO layer modified PVDF membranes exhibited a simultaneously enhanced permeability, rejection and antifouling property in protein filtration and oil/water emulsion filtration, and humic acid filtration, respectively. Moreover, the as-prepared membranes had prominent long-term stability even in harsh conditions due to strong hydrogen-bonded interactions between PACMO and PDA. This work provided a practical strategy for hydrophilizing membrane surfaces by hydrogen bonding self-assembly.

Porphyrin and its derivatives have become the second-generation photosensitizers for photodynamic therapy (PDT). Three water-soluble porphyrins containing halogen atoms (F, Cl, Br) were synthesized by N-pyridyl substituted alkylation reaction. We found that P3 has the highest singlet oxygen generation capacity and the results of density functional theory (DFT) further support this result. MTT assay was used to study cytotoxicity, which proved that P1-P3 have good phototoxicity and high selectivity. Fluorescence imaging and intracellular reactive oxygen species illustrate cell apoptosis and reactive oxygen species (ROS) production. High ROS production, excellent phototoxicity ensure that photosensitizers become potential candidates for PDT drugs.

Hydrophilic polymer brushes on membrane surfaces can alleviate fouling during the separation of oil/water emulsions; the charged moieties on the polymer brushes presumably interact with charged surfactants and weaken the membrane fouling behaviour. However, the oil-repellence mechanism of nonionic polymer brushes has not been thoroughly examined. In this study, a nonionic poly(N-acryloyl morpholine)-brush-grafted-poly(vinylidene fluoride) membrane (PVDF-g-PACMO) was fabricated via surface-initiated atom transfer radical polymerisation (ATRP) to separate various surfactant-stabilised emulsions. PVDF-g-PACMO membranes with high hydrophilicity and high permeation were successfully fabricated by controlling the duration of ATRP. Furthermore, fouling models of oil/water emulsions stabilised by anionic, nonionic, and cationic surfactants were examined. Multicycle filtration experiments revealed that the anionic surfactant-stabilised emulsions severely fouled the similarly charged PVDF-g-PACMO membranes owing to electrostatic repulsion, whereas the nonionic and cationic surfactant-stabilised emulsions exhibited reduced irreversible fouling. In particular, an unusual relief in irreversible membrane fouling was observed with respect to the cationic surfactant-stabilised emulsions, presumably because of strong demulsification and steric effects (surfactant barrier), which repelled the penetration of oil droplets into the internal pores and averted pore blockage. These observations suggest that oppositely charged surface potentials of the PVDF-g-PACMO membranes compared to that of the oil/water emulsions assist in mitigating irreversible fouling. The mechanisms examined herein described the relationship between the surface properties of the oil/water emulsions and the tendency for irreversible fouling, thereby providing valuable guidance for sustainable separation of oil/water emulsions.

Tetrad novel Cu-complex containing multifarious meso-10,15,20-Tris (N-methyl-2′-pyridyl)-5-(4′- X- acylhydrazone) porphyrin ligands, where X respectively referred to salicylaldehyde ( Cu-P1 ), o-Vanillin ( Cu-P2 ), pyridine-2-carboxaldehyde ( Cu-P3 ) and acetone ( Cu-P4 ), have been successfully isolated and well characterized. Multiple physicochemical approaches reveal the complex Cu-P4 with preferable binding affinity than its analogues due to smaller molecular dimension. Moreover, the mechanism of the anti-neoplasm action of these conjugates have been appraised via MTT assay, manifesting all of them possess superior cytotoxicity towards A549 (non-small cell lung cancer) and HepG2 (liver hepatocellular carcinoma cells) but weak cell toxicity for Hs 578Bst (human normal breast cells) which might be boiled down to porphyrin derivatives could enrich around malignant neoplasms. The flow cytometric analysis illustrates that delegate compound Cu-P4 induced cell death predominantly through late apoptosis and arrested S phase cells.

Porphyrin sensitizers have attracted great attention due to their admirable performance in dye-sensitized solar cell (DSSC). In this work, three antenna zinc porphyrins ZnPi (i = 1–3) and anchored porphyrin ZnPA have been designed, synthesized, and characterized. The antenna molecules ZnPi adhere on to the anchored porphyrin ZnPA via metal–ligand axial coordination self-assembly, and then the ZnPA bonding to nanostructured TiO2 to prepared ZnPi(i = 1–3)-ZnPA based DSSCs. Optical performance analysis showed that the devices based on self-assemblies exhibited obviously enhanced light-harvesting ability than the monomer anchor molecule ZnPA. The photovoltaic results showed that, compared with the ZnPA-sensitized solar cell, the ZnPi(i = 1–3)-ZnPA-sensitized solar cells have higher short - circuit photocurrent density (Jsc). However, the open circuit voltage (Voc) of the self-assembled porphyrin-sensitized solar cells are lower than the ZnPA-sensitized solar cell, this is because of the increase of charge recombination rate of the self-assembled porphyrin-sensitized solar cells on the electrode. As a result, the devices based ZnPi (i = 1–3)-ZnPA exhibited enhanced photoelectric conversion efficiency (PCE) than monomer ZnPA-sensitized solar cell. Especially for the ZnP3-ZnPA-sensitized solar cell with a optimal PCE is 3.44%, indicating that the trifluoromethyl substituent of the antenna molecule ZnP3 porphyrin was a more suitable group. Additionally, density functional theory (DFT) calculations are used to further verify the test results of the assembled sensitized solar cells. Therefore, our new method, metal-ligand self-assembly strategy provides new ideas for the high-performance DSSC.

In this work, ZnO nanorods (ZnO NRs) with different sizes were hydrothermally grown on the surface of Whatman filter paper for the fabrication of a microfluidic paper-based device (μPAD) for the simultaneous detection of glucose and uric acid. As dual enzymatic reaction was employed for the colorimetric detection in this μPAD, the presence of ZnO NRs promoted the enzyme immobilization thus significantly enhancing the colorimetric signal. The coffee ring effect was effectively conquered by the uniform distribution of ZnO NR as well as a specialized double-layered μPAD design. Meanwhile, two color indicators with distinct colors were used to provide complementary results to better quantify the concentration of the analytes by naked eye. As a result, two linear calibration curves were obtained for the detection of glucose (0.01–10 mmol L−1) and uric acid (0.01–5 mmol L−1), along with a LOD of 3 μmol L−1 for glucose and 4 μmol L−1 for uric acid, respectively. The practical usefulness of the proposed μPAD was further validated by the simultaneous analysis of glucose and uric acid in serum samples and urine samples.

Defatted walnut meal protein was hydrolyzed using alcalase to yield tyrosinase inhibitory peptides. After separation by ultrafiltration and Sephadex G-25, the fraction with the highest tyrosinase inhibitory activity was identified using liquid chromatography-tandem mass spectrometry and 606 peptides were obtained. Then, molecular docking was used to screen for tyrosinase inhibitory peptides and to clarify the theoretical interaction mechanism between the peptides and tyrosinase. A peptide with the sequence Phe-Pro-Tyr (FPY, MW: 425.2 Da) was identified and the synthesized peptide inhibited tyrosine monophenolase and diphenolase with IC50 values of 1.11 ± 0.05 and 3.22 ± 0.09 mM, respectively. The inhibition of tyrosinase by FPY was competitive and reversible. Good stability of FPY toward digestion was observed in an in vitro gastrointestinal digestion simulation experiment. These results indicated that FPY can be used as a potential tyrosinase inhibitor in the food, medicine, and cosmetics industries.

Ethnopharmacological relevance The Dang-Gui-Si-Ni (DGSN) decoction as a classic prescription has been widely used for thousands of years in the clinical practice of traditional Chinese medicine (TCM). Especially in recent years, the potential efficacy of TCM for the treatment of Raynaud's syndrome has attracted great attention as there are still no specific remedies for this disease. However, the active constituents and underlying mechanisms responsible for the therapeutic benefits are not well understood, which makes it difficult to ensure quality control or to design research and drug development strategies. To identify the potential pharmacodynamic ingredients (PPIs) of TCM will help to achieve suitable process control procedures for industrial production and large-scale manufacturing. Aim of the study In the present study, we propose a multi-dimensional qualitative analysis method combining water-decoction spectra, in-vitro intestinal absorption spectra, in-vivo plasma spectra, and molecular docking of components to quickly identify the PPIs for the DGSN decoction of TCM. Materials and methods Water-based decoctions of DGSN were prepared in accordance with the clinical use registered in ancient books. Ultra-high-performance liquid chromatography-quadrupole-time of flight mass spectrometry (UHPLC-Q/TOF-MS) coupled with computerized modelling activity screening was used to quickly identify the PPIs of the DGSN decoction. Bioactive compounds absorbed in vitro were identified using the everted intestinal sac model from rats and compounds absorbed in vivo were confirmed in portal vein blood samples obtained following oral administration in rats. Molecular docking validation experiments were adopted to predict the binding activity to coagulation factors I, II, VII, X, and IX. The active components were further confirmed by pharmacodynamics analysis. The anticoagulant activity of the DGSN decoction was verified using rat models. Results Thirty-one compounds were identified in the DGSN decoction. According to the in vivo experiments, 22 compounds that could be absorbed in vivo were detected by the everted intestinal sac model in rats. This model greatly reduces the scope of PPIs and is easy to perform. Ten compounds were detected in the portal vein blood in rats. The compounds detected in plasma provide stronger evidence supporting the PPIs. Molecular docking in vitro experiments indicated that 7 compounds exhibited better binding activity with coagulation factors I, II, VII, X, and IX. The animal experiments confirmed that the DGSN decoction could improve the microcirculation, providing indirect proof of anticoagulant activity suggested by the molecular docking studies. Finally, based on the multi-dimensional methods, 9 potential compounds present in the DGSN decoction were identified as PPIs (i.e., ferulic acid, paeoniflorin, albiflorin, chlorogenic acid, cryptochlorogenic acid, liquiritin, liquiritin apioside, cinnamaldehyde and glycyrrhizic acid). Conclusion Overall, this study combined the water-decoction spectra, intestinal absorption spectra in vitro, plasma spectra in vivo, and molecular docking studies to establish a multi-dimensional qualitative analysis method of the DGSN decoction. Meanwhile, 9 compounds in DGSN decoction were identified as PPIs using this method, and are proposed for application as quality standards for complex TCM prescriptions.

In this work, we presented a theoretical investigation of single-triplet excited state transition process by the energy gap (ΔEST) and spin-orbit coupling (SOC) for a series of novel designed anthraquinone compounds in solution. The molecular conformation, steady-state spectra and molecular orbitals were performed by quantum chemistry calculations to investigate the substituent effects on the ΔEST and SOC and single-triplet state transition process. The molecular conformation gradually change from the planar of the ground state to torsion, which reduced the orbital overlap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO). It was further demonstrated that the ΔEST and SOC remarkably depend on substituents with different conjugation and the presence of benzene in the donor units in solution. The change of ΔEST from 1.80 eV to 0.70 eV and SOC from 0.495 cm−1 to 5.127 cm−1. Furthermore, it was confirmed that the presence of benzene ring and the enhancement of conjugation in the donor substituent can reduce the ΔEST and enhance the SOC in different anthraquinone compounds. This work paves a way for an understanding of the single-triplet excited state transition process controlled by ΔEST and SOC characters of these kinds of anthraquinone compounds in solution.

Quercetin, a naturally occurring flavonoid, has been reported to exert antidepressant effects, however, the underlying mechanisms are still uncertain. Recent studies have demonstrated that Forkhead box transcription factor G1 (FoxG1) regulates the process of adult hippocampal neurogenesis (AHN) and exerts neuroprotective effects. In this study, we explored whether quercetin plays an anti-depressant role via regulation of FoxG1 signaling in mice and revealed the potential mechanisms. To explore the antidepressant effects of quercetin, mice were subjected to behavioral tests after a chronic unpredictable mild stress (CUMS) exposure. We found that chronic quercetin treatment (15 mg/kg, 30 mg/kg) obviously restored the weight loss of mice caused by CUMS and alleviated CUMS-induced depression-like behaviors, such as increased sucrose consumption, improved locomotor activity and shorten immobility time. In addition, to clarify the relationship between quercetin and AHN, we detected neurogenesis markers in the dentate gyrus (DG) of the hippocampus. Furthermore, FoxG1-siRNA was employed and then stimulated with quercetin to further investigate the mechanism by which FoxG1 participates in the antidepressant effects of quercetin. Our results indicate that chronic quercetin treatment dramatically increased the number of doublecortin (DCX)-positive and BrdU/NeuN-double positive cells. Besides, the expression levels of FoxG1, p-CREB and Brain-derived neurotrophic factor (BDNF) were also enhanced by quercetin in the DG. Strikingly, quercetin failed to reverse the levels of p-CREB and BDNF after FoxG1-siRNA was performed in SH-SY5Y cells and Neural Progenitor Cells (NPCs). Our results thus far suggest that quercetin might exert antidepressant effects via promotion of AHN by FoxG1/CREB/ BDNF signaling pathway.

The molecular structures of 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), were calculated by using time-dependent density functional theory (TDDFT) model with M062X method with 6-311G (d, p) basis set. In this work, the ABTS were theoretically investigated from the geometric structure, the energy levels of the lowest unoccupied molecular orbital (LUMO) and the highest occupied molecular orbital (HOMO), the energy level gap ΔEHOMO-LUMO of the molecular ground state, excited stated properties and the electronic absorption spectra of different oxidation states. We studied the energy levels of LUMO and HOMO of ABTS in different oxidation states. Frontier molecular orbital analysis can provide insight into the nature of excited states. ABTS was synthesized from N-ethylamine by total synthesis. Then, we measured the UV-Vis spectra of ABTS before and after being oxidized by K2S2O8. The calculated electronic structures and photochemical properties of different oxidation state of ABTS were in accordance with the experimental result. This work demonstrates the relationship between the electronic structures and photochemistry of different oxidation states ABTS hence paves the way for the rationally synthesis and deepen understanding of the photophysical properties of ABTS materials.

Temperature-sensitive poly(vinylidene fluoride)-graft-poly(N-isopropylacrylamide)(PVDF-g-PNIPAAm) copolymer was synthesized and its flat membranes were prepared through phase inversion method with ...

Nonionic polymers (i.e., poly(ethylene glycol) (PEG), poly(vinyl alcohol) (PVA), poly(N-vinyl pyrrolidone) (PVP), and poly(N-acryoyl morpholine) (PACMO)) have been reported as promising antifouling materials for membrane surface modification. Better understanding of similarity and difference for the nonionic polymers in terms of hydration capability and antifouling property will benefit the design and development of antifouling surfaces. Herein, two simple and scalable methods yielded composite coatings on the hydrophobic polymer membrane surfaces: (i) a codeposition of polydopamine (PDA) with PEG (or PVA) (labeled as MPDA-PEG and MPDA-PVA), and (ii) a sequential deposition featuring dopamine polymerization followed by the self-assembly of PVP (or PACMO) (labeled as MPDA-PVP and MPDA-PACMO) via hydrogen-bonded interactions. The results suggested that hydrophilicity and surface free energy of all modified membranes were significantly enhanced after introducing PDA and nonionic polymers. The order of improved initial water flux of these modified membranes was MPDA-PEG > MPDA-PVP ≈ MPDA-PVA > MPDA-PACMO. It was appeared that the codeposited membranes (MPDA-PEG and MPDA-PVA membrane) with excellent hydration capability and permeability had better antifouling property. However, antifouling property and durability were remarked for the sequentially deposited membranes (MPDA-PVP and MPDA-PACMO membrane) in comparison to the codeposited membranes as evaluated in protein filtration, oil/water emulsion filtration, and humic acid filtration. The hydration capability of hydrogen-bonded PDA-PVP (or PDA-PACMO) coating endows the sequentially deposited membranes with robust and comprehensive performance. This work systematically demonstrates that coating architecture is a vital role in the design of the nonionic polymer modified membranes.

The floatability of solid particles on the water surface governs many natural phenomena and industrial processes including film flotation and froth flotation separation of coal and valuable minerals. For many years, the contact angle (CA) has been postulated as the key factor in determining the particle floatability. Indeed, the maximum force (tenacity) supporting the flotation of fine spheres was conjectured to occur when the apical angle of the contact circle is equal to the contact angle. In this paper, the model predictions are reviewed and compared with experimental results. It is shown that CA can be affected by many physical and chemical factors such as surface roughness and chemical heterogeneity and can have a range of values known as the CA hysteresis. This multiple-valued CA invalidates the available theories on the floatability of spheres. Even the intuitive replacement of CA by the advancing (maximum) CA in the classical theories can be wrong. A few new examples are also reviewed and analyzed to demonstrate the significance of CA variation in controlling the particle floatability. They include the pinning of the contact line at the sharp edge, known as the Gibbs inequality condition, and the nearby interaction among floating particles, known as lateral inter-particle interaction. It is concluded that our quantitative understanding of the floatability of real particles being irregular and heterogeneous both morphologically and chemically is still far from being satisfactory.

OBJECTIVE To determine serum bile acid (BA) and fatty acid (FA) profiles in Chinese children with non-alcoholic fatty liver disease (NAFLD). METHODS A total 76 children aged 4–17 years were categorized into three groups according to the presence and absence of as well as the severity of NAFLD, that is, non-NAFLD (control), mild and moderate to severe NAFLD groups, respectively, based on their liver ultrasonography findings. Serum BA and FA profiles were quantified separately by mass spectrometry and gas chromatography. General linear models were performed to assess the differences among the groups. RESULTS After adjusted for potential confounders, children with NAFLD had higher levels of chenodeoxycholic acid (CDCA), unconjugated primary BAs (CDCA + cholic acid) but lower levels of deoxycholic acid (DCA), taurodeoxycholic acid (TDCA), glycodeoxycholic acid (GDCA), total DCA (DCA + TDCA + GDCA), glycolithocholic acid (GLCA) and total lithocholic acid (GLCA + taurolithocholic acid) than children without NAFLD. As for FAs, children with mild and moderate to severe NAFLD had higher levels of n-7 monounsaturated FA. CONCLUSIONS Circulating BA and FA profiles may change in children with NAFLD. Further studies are needed to determine their associations and to understand the underlying mechanism of action.

In this paper, UV-resistant polypropylene (PP) fibers were prepared with a simple and versatile strategy. The PP fiber was firstly coated a polydopamine (PDA) layer by simply dipping the fiber into an alkaline dopamine solution. Then, the titania (TiO2) nanoparticles were chemically bound to the PDA layer through the reduction capacity of catechol groups in PDA, endowing the fibers with excellent UV-resistant properties. The surface chemical composition of modified fibers was confirmed by attenuated total reflectance fourier transform infrared (ATR-FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). The surface morphology and the crystalline structure of the modified fibers were studied by scanning electron microscopy (SEM) and X-ray diffraction (XRD) respectively. Thermo stability was characterized by thermogravimetry analysis. Besides, the mechanical and UV protection properties were further investigated through monofilament tensile and the UV transmittance test. The results showed that the PDA and TiO2 were successfully coated on fiber surface. Comprared to the pristine fiber, the modified fiber exhibited better thermal stability. Particularly, the as-prepared PP-PDA-TiO2 fibers could strongly resist the UV rays with no change in mechanical properties.

The poly(vinylidene fluoride) (PVDF)/chitin (CH) blend membranes were prepared by the immersion phase inversion method using N,N-dimethylacetamide (DMAc)/lithium chloride (LiCl) as the co-solvent. It was found that blending CH with PVDF allowed membranes to have a better hydrophilicity, penetrability, antifouling and antibacterial performance. In order to improve the performance of PVDF/CH blend membranes further, water/ethanoic acid (HAc) solutions with different compositions were employed as coagulation baths. The effects of HAc volume percentage in coagulation baths on the surface composition, morphology, wettability, water flux, antifouling and antibacterial property of PVDF/CH membrane were investigated. The results indicated that the content of CH on the surface of the membrane increased with the increase of HAc concentration in coagulation baths, which contributed to an improvement of hydrophilicity. The increasing HAc content in coagulation baths also led to a change from finger-like pores to sponge-like pores and a decrease of porosity for PVDF/CH blend membranes. When increasing HAc concentration, the antifouling performance of the blend membranes was improved. Meanwhile, the amidogen of CH on PVDF/CH membrane surfaces could suppress the growth of bacteria, and the blend membrane showed an improved antibacterial performance with the volume ratio of HAc increasing.

Ethanol's aversive property may limit it's use, but the underlying mechanisms are no well-understood. Emerging evidence suggests a critical role for the lateral habenula (LHb) in the aversive response to various drugs, including ethanol. We previously showed that ethanol enhances glutamatergic transmission and stimulates LHb neurons. GABAergic transmission, a major target of ethanol in many brain regions, also tightly regulates LHb activity. This study assessed the action of ethanol on LHb GABAergic transmission in rat brain slices. Application of ethanol accelerated spontaneous action potential firing of LHb neurons, and LHb activity was increased by the GABAA receptor antagonist gabazine, and ethanol-induced acceleration of LHb firing was further increased by gabazine. Additionally, ethanol potentiated GABAergic transmission (inhibitory postsynaptic currents, IPSCs) with an EC50 of 1.5 mM. Ethanol-induced potentiation of IPSCs was increased by a GABAB receptor antagonist; it was mimicked by dopamine, dopamine receptor agonists, and dopamine reuptake blocker, and was completely prevented by reserpine, which depletes store of catecholamine. Moreover, ethanol-induced potentiation of IPSCs involved cAMP signaling. Finally, ethanol enhanced simultaneously glutamatergic and GABAergic transmissions to the majority of LHb neurons: the potentiation of the former being greater than that of the latter, the net effect was increased firing. Since LHb excitation may contribute to aversion, ethanol-induced potentiation of GABAergic inhibition tends to reduce aversion.

Ultrahigh molecular weight polyethylene (UHMWPE) fibers exhibit excellent mechanical property, but their low surface activity limits the application in many fields. In this work, an efficient method was used to improve the surface activity and adhesion property of UHMWPE fibers. The amine functionalized UHMWPE fibers were prepared by the combination of bio-inspired polydopamine (PDA) and grafted hexamethylene diamine (HMDA). The chemical structure of UHMWPE fibers was characterized by X-ray photoelectron spectroscopy and attenuated total reflectance Fourier transform infrared spectroscopy. The surface morphologies and mechanical property of the fibers were investigated by scanning electron microscopy and tensile testing respectively. In addition, a single-fiber pull-out test was carried out to investigate the adhesion property of the fibers with epoxy resin matrix. The results showed that PDA was coated on the surface of UHMWPE fibers and then HMDA was successfully grafted on the PDA layers. The excellent mechanical property of UHMWPE fibers had no obvious change. Compared with the pristine UHMWPE fibers, the interfacial shear strength of the PDA coated UHMWPE fibers with the epoxy resin matrix improved by 28.3%, while the IFSS of the HMDA grafted UHMWPE fibers had an increase of 82.7%. Copyright © 2017 John Wiley & Sons, Ltd.

Polarization-beam-splitters with both broadband operation window and high extinction ratio are highly desirable in optical communication systems. In this paper, a compact noncascaded-directional-couplers PBS with an ultrahigh extinction ratio and low excess loss is proposed. The PBS utilizes an asymmetrical directional coupling structure consisted of a TE-pass-polarizer waveguide and a TE- and TM-pass waveguide. The simulation results show that the extinction ratio is up to 35.41 dB and the excess loss is only 0.11 dB around the central wavelength 1550 nm for both polarizations (TE and TM). Meanwhile, when the extinction ratio is 30, 25, and 20 dB, the corresponding bandwidth is 72, 145, and 188 nm, respectively. Also, the EL is 1 and 0.5 dB in a bandwidth of ∼73 and ∼48 nm, respectively. A fabrication tolerance of ±10 nm for the waveguide width is also achieved.