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The development of efficient method to prepare poly(silyl ether)s (PSEs) is highly desirable. Herein, an environmentally sustainable copper-catalyzed dehydrocoupling polymerization was developed with good yields and high molecular weight (up to 48400 of Mn and up to 97% yield). Monomers of different types (AB type or AA and BB type) are suitable to afford PSEs. The PSEs show good thermal stability and low glass-transition temperature.

Aim: The present study aims to investigate the effect of flavonoids from stem and leaf of Scutellaria Baicalensis Georgi (SSF) on multi-sites phosphorylation of tau protein in the cerebral cortex and hippocampus of rats induced by okadaic acid (OA) and the regulative mechanism of the protein kinases. Methods: The model of AD-like memory impairment and neuronal injuries was established in male SD rats who were microinjected with OA (200 ng/kg) to establish a memory impairment model and screened for successful model rats by Morris water maze on day 21 after surgery. The successful model rats were continuously administered with intragastric infusion (ig) SSF 25, 50 and 100 mg/kg or Ginkgo biloba leaves flavonoids (GLF) 200 mg/kg for 36 d. The relative protein expressed levels of phosphorylated tau protein at sites of Ser199, Ser202, Ser214, Ser404 and Thr231, protein kinases (CDK5, PKA, pTyr216-GSK3β and pSer9-GSK3β) were detected by Western blotting. Results: The relative protein expressed levels of p-tau(Ser199), p-tau(Ser202), p-tau(Ser214), p-- tau(Ser404), p-tau(Thr231) and pTyr216-GSK3β were significantly increased in both cerebral cortex and hippocampus regions of the model rats subjected to intracerebroventricular injection of OA (P Conclusion: The results demonstrated that SSF could inhibit the hyperphosphorylation of tau in rats’ cerebral cortex and hippocampus induced by microinjection of OA, which may be related to the activities of protein kinase CDK5, PKA and GSK3β.

A facile method for kinetic resolution of [2.2]paracyclophane-derived cyclic N-sulfonylimines based on palladium-catalyzed addition of arylboronic acids was developed, giving two kinds of planar chiral [2.2]paracyclophane derivatives in excellent diastereoselectivities and up to 99% of enantioselectivities with high selectivity factors (s up to 128).

The precise synthesis of chiral poly(silyl ether)s remains a challenge, in contrast to the well-studied preparation of poly(silyl ether)s. Herein, an unprecedented approach for the synthesis of optically active poly(silyl ether)s with main-chain chirality has been developed via CuH-catalyzed hydrosilylation polymerization of diketones and silanes. The polymerization features low catalyst loading, mild condition, and broad substrate scope, including a wide range of aromatic diketones and heteroaromatic diketones with excellent yields and enantioselectivities (up to 98% yield and 99% ee). Thermal analysis indicated chiral poly(silyl ether)s exhibit good thermal properties. These enantiomerically enriched poly(silyl ether)s with good thermal stability have a promising application in chiral separation.

Partially biobased polysilylethers (PSEs) are synthesized via dehydrocoupling polymerization catalyzed by an anionic iridium complex. Different types (AB type or AA and BB type) of monomers are suitable. Levulinic acid (LA) and succinic acid (SA) have been ranked within the top 10 chemicals derived from biomass. BB type monomers (diols) derived from LA and SA have been applied to the synthesis of PSEs. The polymerization reactions employ an air-stable anionic iridium complex bearing a functional bipyridonate ligand as catalyst. Moderate to high yields of polymers with number-average molecular weights (Mn) up to 4.38 × 104 were obtained. A possible catalytic cycle via an Ir-H species is presented. Based on the results of kinetic experiments, apparent activation energy of polymerization in the temperature range of 0–10 °C is about 38.6 kJ/mol. The PSEs synthesized from AA and BB type monomers possess good thermal stability (T5 = 418 °C to 437 °C) and low glass-transition temperature (Tg = −49.6 °C).

ObjectiveEndometriosis is an estrogen-dependent chronic disease. The abnormal proliferation and invasion of ectopic stromal cells (ESCs) are important manifestations of endometriosis, and it is necessary to find safer and more effective treatments. Extracellular vesicles (EVs) derived from human umbilical cord mesenchymal stem cells (UC-MSCs) have been shown to be promising for the treatment of many diseases, except endometriosis. The main purpose of this study was to explore the effect of EVs derived from UC-MSCs on ESCs and evaluate the therapeutic value of EVs on endometriosis.Study DesignFollowing the successful culture and identification of UC-MSCs, we collected the medium of UC-MSCs and extracted EVs by ultracentrifugation. Then, 120 μg/mL EVs were used to stimulate ESCs, which were collected to evaluate cell proliferation and invasion and expression of the estrogen-related proteins steroidogenic factor-1 (SF-1), estrogen receptors β (ERβ), and aromatase.ResultsCompared with the control group treated with isodose phosphate buffered saline (PBS), 120 μg/mL EVs exposure significantly decreased the expression of cyclin D1 (mRNA: n = 6, P = 0.02; protein: n = 6, P = 0.000) and matrix metalloproteinase (MMP) 9 (mRNA: n = 6, P = 0.04; protein: n = 6, P = 0.000) of ESCs, which were consistent with Cell Counting Kit-8(CCK-8) results (day 0: NC: 0.29 ± 0.04, 120 μg/mL EVs: 0.28 ± 0.04; day 1: NC: 0.42 ± 0.08, 120 μg/mL EVs: 0.32 ± 0.01; day 2: NC: 0.64 ± 0.07, 120 μg/mL EVs: 0.50 ± 0.05, P = 0.000; day 3: NC: 0.82 ± 0.09, 120 μg/mL EVs: 0.65 ± 0.07, P = 0.000; day 4: NC: 0.95 ± 0.11, 120 μg/mL EVs: 0.76 ± 0.07, P = 0.012; n = 6) and Transwell experiments (n = 6, P = 0.000). In addition, the expression of SF-1 (encoded by NR5A1; mRNA: n = 6, P = 0.000; protein: n = 6, P = 0.000), ERβ (encoded by ESR2; mRNA: n = 6, P = 0.000; protein: n = 6, P = 0.000), and aromatase (encoded by CYP19A1; mRNA: n = 6, P = 0.04; protein: n = 6, P = 0.000) in ESCs decreased significantly.ConclusionTaken together, the results show that 120 μg/mL EVs derived from UC-MSCs can effectively inhibit the proliferation and invasion of ESCs, as well as their expression of SF-1, ERβ and aromatase, and thus may lead to the alleviation of endometriosis.

Two novel metal–organic frameworks, formulated as [Mn(CIP−)2] (1) and [Ag(CIP−)] (2) (HCIP = 4-(4-carboxylphenyl)-2,6-di(4-imidazol-1-yl)phenyl)pyridine), were solvothermally synthesized based on a pyridyl-imidazole-carboxyl multifunctional ligand. The single-crystal X-ray diffraction analysis shows that complex 1 is a 3D microporous framework with uncoordinated imidazole groups, and complex 2 is a 2D + 2D → 2D 3-fold parallel interpenetrated network. Complex 1 exhibited excellent CO2 selective absorption over N2 and CH4. IAST calculations revealed that the selectivities of 1 for the CO2/CH4 (50 : 50) and CO2/N2 (15 : 85) mixtures were 8.0 and 117 at 273 K under 1 bar, respectively. Moreover, the luminescence investigations displayed that complex 2 is an excellent MOF-based multiresponsive fluorescent probe for Fe3+, CrO42−/Cr2O72− and the pesticide 2,6-Dich-4-nitroaniline, with high selectivity and sensitivity. Notably, complex 2 exhibited a highly sensitive sensing ability (5.2 × 104 M−1) and a low detection limit (1.7 × 10−7 M) for 2,6-Dich-4-nitroaniline. To the best of our knowledge, this is the first Ag-MOF-based fluorescent sensor that can simultaneously detect metal ions, inorganic anions and pesticides.

Tuning the emissive color changes of lanthanide (Ln) complexes is an important and appealing project for promoting the applications of Ln-complexes. A solvothermal reaction of 4-cyano-3-methylbenzoic acid (HL) and Ln(NO3)3·6H2O affords three isostructural Ln-complexes [Eu(L)3(H2O)2]n (1-Ln) (Ln = Eu, Gd and Tb) with one-dimensional chain structures. 1-Eu and 1-Tb show bright red and green emissions with absolute quantum yields of 3.06% and 11.96%, respectively, and the energy transfer was analyzed in detail through combined calculations. Interestingly, a series of heterometallic doped 1-TbxEu1-x coordination polymers were also obtained by mixing different ratios of Eu3+ and Tb3+ ions, which possess continuous luminescent color changes from green to yellow, orange and red. In addition, 1-Eu exhibits high quenching efficiency and low detection limit (∼10-4 M) for the simultaneous sensing of MnO4-, CrO42- and Cr2O72- ions in water.

The aim of the present study was to determine whether the effects and underlying mechanisms of ticagrelor in a rat model of sepsis-induced acute kidney injury (AKI) were mediated via the CD62P pathway. A total of 15 rats were randomly assigned to the following groups: Normal, sham, cecal ligation and puncture (CLP), CLP + clinical dose of ticagrelor (CCD) and CLP + loading dose of ticagrelor (CLD). Ticagrelor was administered 12 h before modeling, immediately after modeling, and 12 h after modeling at a dose of 8.6 and 46.42 mg/kg in the CCD and CLD groups, respectively. Rats in the normal, sham and CLP groups were treated with the same volume of distilled water. Serum creatinine (SCr), CD62P and interleukin-1β (IL-1β) levels, myeloperoxidase (MPO) activity in the renal tissue and the apoptosis rate of renal cells were increased in the CLP group, compared with in the normal and sham groups (P

Rationale: In 2017, the U.S. Centers for Disease Control and Prevention (CDC) developed a new surveillance definition of sepsis, the adult sepsis event (ASE), to better track sepsis epidemiology. The ASE requires evidence of acute organ dysfunction and defines baseline organ function pragmatically as the best in-hospital value. This approach may undercount sepsis if new organ dysfunction does not resolve by discharge. Objectives: To understand how sepsis identification and outcomes differ when using the best laboratory values during hospitalization versus methods that use historical lookbacks to define baseline organ function. Methods: We identified all patients hospitalized at 138 Veterans Affairs hospitals (2013–2018) admitted via the emergency department with two or more systemic inflammatory response criteria, were treated with antibiotics within 48 hours (i.e., had potential infection), and completed 4+ days of antibiotics (i.e., had suspected infection). We considered the following three approaches to defining baseline renal, hematologic, and liver function: the best values during hospitalization (as in the Centers for Disease Control and Prevention’s ASE), the best values during hospitalization plus the prior 90 days (3-mo baseline), and the best values during hospitalization plus the prior 180 days (6-mo baseline). We determined how many patients met the criteria for sepsis by each approach, and then compared characteristics and outcomes of sepsis hospitalizations between the three approaches. Results: Among 608,128 hospitalizations with potential infection, 72.1%, 68.5%, and 58.4% had creatinine, platelet, and total bilirubin measured, respectively, in the prior 3 months. A total of 86.0%, 82.6%, and 74.8%, respectively, had these labs in the prior 6 months. Using the hospital baseline, 100,568 hospitalizations met criteria for community-acquired sepsis. By contrast, 111,983 and 117,435 met criteria for sepsis using the 3- and 6-month baselines, for a relative increase of 11% and 17%, respectively. Patient characteristics were similar across the three approaches. In-hospital mortality was 7.2%, 7.0%, and 6.8% for sepsis hospitalizations identified using the hospital, 3-month baseline, and 6-month baseline. The 30-day mortality was 12.5%, 12.7%, and 12.5%, respectively. Conclusions: Among veterans hospitalized with potential infection, the majority had laboratory values in the prior 6 months. Using 3- and 6-month lookbacks to define baseline organ function resulted in an 11% and 17% relative increase, respectively, in the number of sepsis hospitalizations identified.

ObjectiveTo assess the effects of 17β-estradiol (E2) on proliferation, apoptosis, and protein expressions of fibroblasts at different concentrations and time intervals to reveal the mechanism of E2 in the treatment of pelvic organ prolapse (POP).Study DesignThe uterosacral ligament fibroblasts were collected from seven POP patients for primary culture of fibroblasts. The culture media containing 0, 10-6, 10-7, 10-8, and 10-9 mol/L E2 were used for 24, 48, 72, and 96 h.Main Outcome MeasuresThe cells were collected for cell counting kit-8 (CCK-8), apoptosis, quantitative reverse transcription polymerase chain reaction (qRT-PCR), and Western blotting assays.ResultsCompared with the control group, in the values of fibroblasts cultured in 10-8 mol/L E2 for 72 h, the proliferation, mRNA and protein expression of Mitofusin-2 (Mfn2) separately increased (P < 0.05), decreased (P-8 mol/L E2 group.ConclusionsE2 can inhibit the progress of POP by inhibiting the expression level of Mfn2, as well as promoting expression of procollagens and proliferation of fibroblasts. This effect is time- and concentration-dependent. Only when the estrogen concentration reaches 10-8 mol/L, the therapeutic effect is the greatest after 72 h.

The pathway of adiponectin (ADPN)/fibroblast growth factor 9 (FGF9) was recently thought as a key role in the development of depression. ADPN is crucially regulated by peroxisome proliferator-activated receptor-gamma (PPAR-γ). Natural material carnosic acid (CA) has been applied for therapeutics of mental disorders. To evaluate the antidepressive effect of CA in stress-treated mice and define whether its effects is involved in the regulation of ADPN/FGF9 pathway. In vivo study, the levels of ADPN and FGF9 in both serum and hippocampus tissues, the expressions of ADPN receptor 2 (AdipoR2) in hippocampus and PPAR-γ in abdominal adipose, as well as the pathological changes of hippocampus were determined in 28-day period of chronic unpredictable mild stress (CUMS)-induced depression model of male ICR (Institute of Cancer Research) mice or adipo−/− mice. In vitro study, the level of ADPN and the mRNA expressions of both ADPN and PPAR-γ were determined in mouse 3T3-L1 preadipocytes. In vivo study, treatment with CA (50 or 100 mg/kg per day) for 21 days markedly suppressed depressive-like behaviors, the elevating levels of FGF9 and decreasing levels of ADPN in both serum and hippocampus tissues, the downregulating protein and mRNA expressions of AdipoR2 in hippocampus and PPAR-γ in abdominal adipose, as well as the pathological injury of hippocampus induced by CUMS in male ICR mice. The antidepressive effects of CA were markedly attenuated in male CUMS-treated adipo−/− mice. In vitro study, incubation with CA (3–30 μmol/L) for 24 h could concentration-dependently upregulate the mRNA expressions of both PPAR-γ and ADPN as well as increase the level of ADPN. The experiments using PPAR-γ-specific inhibitor GW9662 and transient transfection with mutated PPAR-γ-binding site promotor constructs showed that the activation of PPAR-γ mediated CA-induced ADPN expression in adipocytes. CA could significantly improve stress-induced depressive disorder, which may be related to regulating the dysfunction of ADPN-FGF9 pathway via activating PPAR-γ in adipocytes.

The solvothermal reaction of CdCl2 or CuCl2 with a pyridine-pyrazole bifunctional ligand 3,5‑diethyl‑4‑(4‑pyridyl)‑pyrazole (Hdeppz) under different solvents afforded two coordination polymers [Cd(Hdeppz)2(Cl)2]n (1) and [Cu4ICuII(deppz)4(Cl)2]n (2), respectively. Owing to different coordinated modes of Hdeppz and metal ions, 1 and 2 display different grid layer structures. In 1, the neutral Hdeppz ligand behaves as a linear linker to connect two Cd2+ ions, while 2 contains not only the Y-shaped deppz linker but also the mixed valence of Cu+ and Cu2+ ions. Meanwhile, an uncommon Cu4(pz)4 metallocyclic unit is formed in 2, and which further produces an unprecedented (CuIICl2CuI4)n supramolecular chain by Cu···Cl interactions. The strong solid-state blue-green luminescence was also observed in 1.

A novel metal–organic framework with the formula [Zn3(DDB)(DPE)]·H2O (1) (H5DDB = 3,5-di(2′,4′-dicarboxylphenyl)benzoic acid and DPE = 1,2-di(4-pyridyl)ethylene) has been solvothermally synthesized by employing a rigid carboxylate ligand H5DDB to assemble with Zn(II) ions in the presence of a flexible bis(pyridyl) linker DPE. The Zn-MOF is a 3D framework with six-nuclear clusters and possesses remarkable water stability and pH stability. Interestingly, complex 1 can sensitively and selectively sense Fe(III), Cr(III), Cr(VI), Mn(VII) and the pesticide 2,6-Dich-4-NA with low detection limits in aqueous solution. Moreover, complex 1 also exhibits selectivity for 2,6-Dich-4-NA detection in real samples including carrot, grape and nectarine extracts, and its detection ability is almost unchanged in the presence of the surfactant sodium dodecyl sulfate (SDS). The possible mechanisms of luminescence quenching have been explained by the weak affinity of nitrogen atoms, resonance energy transfer, and photoinduced electron transfer. To our knowledge, this is the first example of a MOF-based multiresponsive fluorescent probe for the simultaneous detection of Fe(III), Cr(III/VI), Mn(VII) and the pesticide 2,6-Dich-4-NA in aqueous solution.

Three isostructural lanthanide metal–organic frameworks (Ln-MOFs), {[Ln2(BDPO)1.5(DMA)3(H2O)]·5H2O }n (1-Ln, Ln = Eu, Gd, and Tb) were constructed by a less-investigated large delocalized π-electron conjugated ligand N,N′-bis(3,5-dicarboxyphenyl)-oxalamide (H4BDPO). 1-Ln reveals unprecedented trinodal (4,4,6)-connected networks based on binuclear cluster units and planar BDPO linkers. Density functional theory (DFT) and time dependent-DFT calculations were performed on the ground and excited states to provide insight into geometries, the frontier molecular orbitals, and singlet and triplet state energies of H4BDPO ligand. 1-Eu and 1-Tb exhibit strong typical red and green emission of Eu3+ and Tb3+ ions, respectively, originating from the highly efficient energy transfer from BDPO to metal centers, as demonstrated by the comparison of triplet excited energies of ligands and metal ions. Importantly, by doping different concentrations of Eu3+ and Tb3+ ions, a series of dichromatic doped 1-EuxTb1-x MOFs were ...

The pre-reduced Bayan Obo ferroniobium (FeNb) ore concentrate block was taken as raw materials for studying the physical properties of niobium-enriched slag and changes in niobium recovery rate. In addition, the dephosphorization rate of the slag under different melting-separation conditions was investigated using the melting-separation test. The research results demonstrate that (i) the niobium recovery rate and dephosphorization rate of the slag decrease with the increase in melting-separation temperature; (ii) the niobium recovery rate of the slag initially increases and then decreases with increase in basicity and time; and (iii) the dephosphorization rate of the slag increases with the increase in basicity and time. When the test was performed under the conditions of basicity of 0.6–0.7, time of 7–10 min, and temperature of 1400–1450 °C, the niobium recovery rate and dephosphorization rate are over 96% and 95%, respectively. By scanning electron microscopy, it is observed that niobium mainly exists in the form of calcium and titanium silicate within the slag phase, with uneven distribution.

CuO / Zn 0.384 Cd 0.616 S was prepared by an impregnation method, and its structure and optical properties were characterized using X-ray diffraction, scanning electron microscopy, ultraviolet–visible diffuse-reflectance spectroscopy and X-ray photoelectron spectroscopy and their photocatalytic activity were evaluated based on photocatalytic degradation of methyl orange (MO) solution under visible light. The effects on photocatalytic degradation of the catalyst amount, MO concentration and pH were investigated. And the mechanism for enhancing the photocatalytic activity was also discussed. The results indicated that 0.5 wt% CuO / Zn 0.384 Cd 0.616 S showed the highest photocatalytic activity among the prepared samples. The mechanism for the degradation of MO occurring on the CuO/Zn 0.384 Cd 0.616 S surface differs from that on Zn x Cd 1− x S surfaces. The catalytic reaction under visible-light irradiation followed pseudo-first-order kinetics.

As a kind of material possessing thermal stability, biocompatibility and degradability, polysilylethers (PSEs) have potential applications. Different catalytic systems have been developed for the synthesis of PSEs. However, the resulted PSEs have similar structure, which is unfavorable for adjusting its properties. We herein synthesized a series of novel PSEs with pendant Si H groups via cobalt-catalyzed selective dehydrocoupling polymerization. Various diols and prochiral silanes are suitable for this method. This novel PSEs could also be obtained via a Co-catalyzed one-pot two-step process. Furthermore, asymmetric dehydrocoupling polymerization was studied and high-Mn PSE was obtained. After the cleavage of PSE by methyl magnesium iodide, chiral silane was obtained with high yield and moderate enantioselectivity.

In order to study the relationship between nutrient pollutants and suspended sediments (SS) in the upper reaches of the Yangtze River and two tributaries, water samples were collected from September 1, 2010 to September 30, 2011 at the Zhutuo, Cuntang, Beibei, Wulong, Qingxichang, Wanxian, and Fengjie cross-sections. In the laboratory, the SS concentration and the concentration of SS whose particle size was smaller than 0.02 mm were measured. The phosphorus (P), nitrogen (N), and permanganate index (CODMn) concentrations in the natural water sample, the settled water sample, and two types of filtered water samples obtained through filter membranes with pore sizes of 0.02 mm and 0.45 μm were monitored synchronously. The results show that there are strong relationships between the P and CODMn concentrations and the SS concentration. P mainly exists in particulate form, while N mainly exists in dissolved form. SS whose particle size is smaller than 0.02 mm accounts for a high proportion of sediments in the Yangtze River and has a strong effect on water quality. At the seven cross-sections, the amounts of P, N, and CODMn in particulate form in the wet season are higher than in the dry season and the adsorption amounts of P, N, and CODMn per unit mass of sediment are higher in the dry season than in the wet season.

A silver-mediated decarboxylative C-S cross-coupling reaction of aliphatic carboxylic acid is described. This reaction occurs smoothly under mild conditions and shows good tolerance of functional groups. It provides an alternative approach for the synthesis of alkyl aryl sulfides.

ObjectiveTo investigate the alteration of plasma levels of omentin-1 and visfatin in elderly patients with coronary heart disease (CHD) and heart failure.MethodsPlasma omentin-1 and visfatin levels were measured in 90 subjects (29 stable angina pectoris (SAP) cases, 30 unstable angina pectoris (UAP) cases and 31 age- and sex-matched healthy controls (age ≥ 60 years) by enzyme-linked immunosorbent assay methods. According to the New York Heart Association classification, 59 CHDs were divided into three groups: functional I class, 11 cases; functional II/III class, 36 cases; and functional IV class, 12 cases.ResultsThe plasma level of omentin-1 in CHD patients was significantly lower than that of the control group. Omentin-1in SAP group and UAP group were significantly lower compared to the control group (there was no statistical significance between UAP group and SAP group; P >0.05). The plasma level of visfatin in CHD patients was significantly higher than that of the control group. Similarly, visfatin in SAP group and UAP group were all significantly higher compared to the control group, while there was no statistical significance between UAP group, and SAP group. The plasma omentin-1 level was negatively correlated with SBP (r=-0.264, P

Neuronal apoptosis mediated by the mitochondrial apoptosis pathway is an important pathological process in cerebral ischemia-reperfusion injury. 14,15-EET, an intermediate metabolite of arachidonic acid, can promote cell survival during ischemia/reperfusion. However, whether the mitochondrial apoptotic pathway is involved this survival mechanism is not fully understood. In this study, we observed that infarct size in ischemia-reperfusion injury was reduced in sEH gene knockout mice. In addition, Caspase 3 activation, cytochrome C release and AIF nuclear translocation were also inhibited. In this study, 14,15-EET pretreatment reduced neuronal apoptosis in the oxygen-glucose deprivation and re-oxygenation group in vitro. The mitochondrial apoptosis pathway was also inhibited, as evidenced by AIF translocation from the mitochondria to nucleus and the reduction in the expressions of cleaved-caspase 3 and cytochrome C in the cytoplasm. 14,15-EET could reduce neuronal apoptosis through upregulation of the ratio of Bcl-2 (anti-apoptotic protein) to Bax (apoptosis protein) and inhibition of Bax aggregation onto mitochondria. PI3K/AKT pathway is also probably involved in the reduction of neuronal apoptosis by EET. Our study suggests that 14,15-EET could suppress neuronal apoptosis and reduce infarct volume through the mitochondrial apoptotic pathway. Furthermore, the PI3K/AKT pathway also appears to be involved in the neuroprotection against ischemia-reperfusion by 14,15-EET.

A 10-week feeding experiment was conducted to evaluate the effects of dietary protein to lipid ratios (P/L) on growth, intestinal digestive enzyme activities and body composition in juvenile rice field eel (Monopterus albus) (initial mean body weight of 65.76 ± 1.07 g, mean ± SEM). Nine test diets were formulated in a 3 × 3 factorial design to contain three protein levels (350, 400 and 450 g kg−1) for each of three lipid levels (40, 80 and 120 g kg−1), respectively. Each diet was randomly assigned to triplicate groups of 60 fish per net cage (1.5 × 2.0 × 1.5 m). Results showed the survival was above 96 % and was not affected by dietary treatments. Fish fed the diet with 450 g kg−1 protein and 40 g kg−1 lipid showed the best weight gain (WG) (103.95 %) and feed conversion ratio (1.60) (P

An experiment was conducted to determine how photosynthesis was affected in Zizania latifolia Turcz. plants by infection of the endophytic smut fungus Ustilago esculenta. The results showed that U. esculenta infection induced a decreased plant height, but significantly increased above-ground biomass production as compared to control plants. Infected plants also exhibited higher Pn and chlorophyll content. In U. esculenta mycelia-sporidial infected plants, Pn, Gs and E generally were higher than those in sporidial infected plants. Compared to control plants, infected plants showed a higher light saturation point (LSP), apparent quantum yield (AQY) but a lower light compensation point (LCP). All leaves at different positions in infected plants showed higher Pn than control plants. The highest Pn was observed in the 4th leaf of infected plants, while it was the 3rd leaf in control plants. Infected plants generally showed relatively higher chlorophyll a fluorescence parameters in ΦPSII, ETR and qP than control plants. Maximum carboxylation rate of Rubisco (Vc, max) and maximum rate of RuBP regeneration (Jmax) were also elevated during U. esculenta infection. Our results revealed that promotion of photosynthetic efficiency was therefore probably mainly due to effects on non-stomatal processes by U. esculenta infection.

To improve the treatment of helminthiasis, filariasis, and colorectal cancer, albendazole-associated chitosan nanoparticles (ABZ-CS-NPs) were prepared using the emulsion crosslinking volatile technique with contained sodium tripolyphosphate as the crosslinking agent and Poloxamer 188 as the auxiliary solvent. The structural characteristics of the NPs were determined using X-ray diffraction to analyze the interaction between CS and the drug. The NPs were then evaluated in terms of their physicochemical characteristics, drug release behavior, in vivo pharmacokinetic parameters, and biodistribution in animal studies. ABZ-loaded NPs with a uniformly spherical particle sizes (157.8 ± 2.82 nm) showed efficient drug loading, encapsulated efficiency, and high physical stability. The drug release from ABZ-CS-NPs was extended over several periods. Kinetic models were then fitted to determine the release mechanisms. ABZ and its metabolite albendazole sulfoxide (ABZSX) were analyzed in rats with mebendazole as the internal standard using reversed-phase high-performance liquid chromatography. Compared with the ABZ suspension groups, the relative bioavailability values of ABZ and ABZSX were 146.05 and 222.15%, respectively. In addition, the plasma concentration versus time curve is consistent with that of the two compartment models in the plasma concentration versus time curve. The results indicate that the ABZ-loaded NPs are promising novel ABZ candidates for passive diffusion in the treatment of hydatid cysts in the liver via oral administration.

The deterioration behavior of cement-fly ash composite binder materials exposed to elevated temperature was studied in the present investigation. With the temperature continuous rising, the surface microstructure evolution of cement-fly ash composite materials was observed in a real-time mode. And the pore structure of the hardened paste undergoing high temperatures was investigated by mercury intrusion porosimetry (MIP) test. The results showed that thermal cracking of hardened paste developed continuously from the surface to the interior and hydration products decomposed gradually with the increase of temperature. Both the processes make the pores of the hardened pastes become coarser as well as the significant increase of the porosity, hence leading to worse deterioration of the microstructure and decline of the strength. The experimental results showed that the morphological effect and micro-aggregate effect of fly ash could improve the microstructure of cement-fly ash composite materials effectively, and the active effect of fly ash reduced the content of calcium hydroxide in the paste significantly. Both of them make contributions to the high temperature resistance of cement-fly ash composite materials.

Tetrabutyl ammonium fluoride (TBAF) was found to be capable of catalyzing the intramolecular hydroalkoxylation of 6-hydroxyhex-2-ynoates and 7-hydroxyhept-2-ynoates. The reaction could be used to prepare 2,5-substituted THF rings and 2,6-substituted THP rings.

Three new metal-organic copper(II) complexes, [Cu(H2PZTC)2]n·2nH2O (1), [Cu(HPZTC)·2H2O]n·2nH2O (2), and Cu2[(PZHD)(OH)(H2O)2]n (3) (H3PZTC = pyrazine-2,3,5-tricarboxylic acid, PZHD 3� = 2-hydroxypyrazine-3,5-dicarboxylate), have been synthesized from Cu(II)/H3PZTC system under different synthetic conditions, and characterized by single-crystal X-ray diffraction, elemental analysis, IR spectroscopy and thermogravimetric analysis. In complexes 1 and 2, H3PZTC ligands loose one and two protons, which were

A novel DNA biosensor system on silica microspheres as solid carriers which based on the fluorescence resonance energy transfer (FRET) was presented in this work when CdTe quantum dots (QDs) were as energy donors and Au nanoparticles (AuNPs) were as energy accepters. Compared with the fluorescent intensity of CdTe QDs, the fluorescent intensity of DNA biosensors decreased extremely, which indicated that the FRET occurred between CdTe QDs and AuNPs. The biosensor system would have a certain degree recovery of fluorescence when the complementary single stranded DNA was introduced into this system. The DNA detection results indicated that this novel fluorescent DNA probe system could recognize the existence of complementary target DNA or not.

Glutin-urea system was used in alumina gelcasting. And alumina suspension with 53vol% solid loading was prepared. Urea was decomposed by using urease therefore it was possible that hydrogen bond could be rebuilt. Alumina greenbodies with 8.26MPa bending-strength were prepared when the dose of urease was 20 iu per milimole urea.

A novel DNA biosensor based on layer-by-layer self-assembled multi-walled carbon nanotubes (MWNTs) functionalized with a mercapto group (SH-MWNTs) and gold nano-particles (GNPs) was presented, where anthraquinone-2-sulfonic acid sodium salt (AQMS) was used as hybridization indicator. The differential pulse voltammetry responses demonstrated that this DNA/GNPs/SH-MWCNTs/Au biosensor was enabled to specifically detect the single-base mismatch DNA sequence in phosphate buffer solution with pH 7.4 containing 0.3 mol/L Na+ and 1.0 mmol/L AQMS. The result showed that when the target DNA concentration was 1.0×10-10 to 1.6×10-5 mol/L, the cathodic peak current of Au electrode system with AQMS as indicator was linearly related to complementary NDA concentration, and the detection limit was about 3.82×10-11 mol/L and had good stability and specificity.

Geometric structures, electronic properties, and stabilities of small Zrn and Zr (n = 2–10) clusters have been investigated using density functional theory with effective core potential LanL2DZ basis set. For both neutral and charged systems, several isomers and different multiplicities were studied to determine the lowest energy structures. Many most stable states with high symmetry were found for small Zrn clusters. The most stable structures and symmetries of Zr clusters are the same as the neutral ones except n = 4 and 7. We found that the clusters with n > 3 possess highly compact structures. The clusters are inclined to form the caged-liked geometry containing pentagonal structures for n > 8, which is in favor of energy. From the formation energy and second-order energy difference, we obtained that 2-, 5-, 7-atoms of neutral and 4-, 7-atoms cationic clusters are the magic numbers. Furthermore, the highest occupied molecular orbital-lowest unoccupied molecular orbital gaps display that the Zr3, Zr6, Zr, and Zr are more stable in chemical stability. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2011

A three-state, multiion kinetic model was proposed to enable the conduction properties of the mammalian channel ClC-0 to be well characterized. Using this rate-theory based model, the current-voltage and conductance-concentration relations were obtained. The five parameters needed were determined by fitting the data of conduction experiments of the wild-type ClC-0 and its K519C mutant. The model was then tested against available calculation and simulation data, and the energy differences between distinct chloride-occupancy states computed agreed with an independent calculation on the binding free energies solved by using the Poisson-Boltzmann equation. The average ion number of conduction and the ion passing duration calculated closely resembled the values obtained from Brownian dynamics simulations. According to the model, the decrease of conductance caused by mutating residue K519 to C519 can be attributed to the effect of K519C mutation on translocation rate constants. Our study sets up a theoretical model for ion permeation and conductance in ClC-0. It provides a starting point for experimentalists to test the three-state model, and would help in understanding the conduction mechanism of ClC-0.

Synthesis of porous titania via mechanical activation of natural ilmenite and subsequent simultaneous dissolution and hydrolysis in dilute solutions of sulfuric acid was investigated by scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), N2 adsorption/desorption measurements, energy-dispersive X-ray spectrometry (EDX) and thermogravimetric analysis (TG). This is a novel template-free approach for synthesis of microporous, mesoporous and micro–mesoporous TiO2 materials. Effects of sulfuric acid concentration and calcination temperature on physicochemical properties of the TiO2 materials were examined systematically. The results show that both the factors considerably affected the porosity of the materials. In a 15% acid solution a microporous TiO2 hydrolysate with BET surface area 109.3 m2/g was prepared. With a 10% H2SO4, we obtained a more pure micro/mesopore TiO2 hydrolysate with BET area of 257.6 m2/g. Calcining the hydrolysate at ⩾500 °C led to the formation of a mesopore TiO2. The mesoporous TiO2 generated at 600 °C still has a BET area of 92.1 m2/g. The high thermal stability is probably related to the presence of H2SO4 in the channel walls of hydrolysate. The XRD analysis indicated all the TiO2 materials prepared in this study being rutile. The mechanism for formation of the porous rutile TiO2 is mainly via in situ hydrolysis and precipitation of the dissolved titanium on the un-reacted ilmenite surface, where H2SO4 may play a very important role.

In order to understand the mechanisms of alcohol-induced neuroapoptosis through the ceramide pathway, sphingomyelin synthase 2 knockout (SMS2-/-) mice were used to make the prenatal alcohol exposure model, and the role of ceramide regulation on alcohol-induced neuroapoptosis was studied in the offspring. Initially the levels of serum sphingomyelin (SM) were detected with enzymatic method in P0 pups after alcohol exposure in parents. Then the apoptosis of mossy cells in the offspring hippocampus was investigated after prenatal alcohol exposure with immunohistochemistry and TUNEL assay. Finally the expression of activated Caspase 8 and activated Caspase 3 in the offspring hippocampus was detected with Western blot analysis. Our results showed that SM levels were down-regulated in a dose-dependent manner (p

A silver-mediated decarboxylative C–S cross-coupling reaction of aliphatic carboxylic acid is described. This reaction occurs smoothly under mild conditions and shows good tolerance of functional groups. It provides an alternative approach for the synthesis of alkyl aryl sulfides.

A highly sensitive and selective fluorogenic probe for fluoride ion, fluorescein di-tert-butyldimethylsilyl ether (FTBS), was designed and synthesized. FTBS was a colorless, non-fluorescent compound and was synthesized via the one-step reaction of fluorescein with tert-butyldimethylsilyl chloride. Upon incubation with fluoride ion in DMF-water solution (7 : 3, V/V), the Si-O bond of FTBS was cleaved, causing a large increase in fluorescence intensity and thereby allowing a selective detection of fluoride ion. The fluorescence increase is linearly with fluoride concentration in the range 0.1-2.0 mumol L(-1) with a detection limit of 0.041 mumol L(-1) (3sigma). The excellent selective signaling behavior of the proposed probe was found to originate from the high affinity of silicon toward fluoride ion. The method has been successfully applied to the fluoride determination in multi-trace elements injection and toothpaste samples, and the results are agreed well with those obtained by the fluoride-ion selective electrode method.

The photovoltaic behaviors of hemin and its organized assembly prepared by Langmuir–Blodgett (LB) technique were studied by surface photovoltage spectroscopy (SPS) and electric field induced surface photovoltage spectroscopy (FEISPS). The SPS of the hemin powder exhibited a strong response originated from the Soret band and a weak response from the Q band. After hemin and the mixture of hemin and n -octadecylamine (ODA) were deposited onto ITO glasses as the thin films by LB technique, the photovoltaic responses became very weak in the whole UV-vis region when no external bias was applied. As the positive external electric field was applied, both pure hemin and the mixture of hemin and ODA LB films showed a strong photovoltaic response at 340 nm.

C v is used in this paper to describe the variation in inhomogeneity of spatial and temporal distribution of precursors. The inhomogeneous variation in the spatial and temporal distribution of the anomalies in water radon and electromagnetic waves before M s≈6 earthquakes in northern North China is analyzed in detail. Results show that before a moderate to strong earthquake, the distribution of anomalies in water radon and electromagnetic waves changes inhomogeneously, i.e., C v increases significantly. The inhomogeneity in spatial distribution of short-to-imminent precursors increases before a strong earthquake, which may relates to the enhancement of crustal strain field. The research will not only help us to know more about the process of seismogeny and to improve practical earthquake prediction, but also blaze a new way to do earthquake prediction with present precursor data.

Mutations in ClC channel proteins may cause serious functional changes and even diseases. The function of ClC proteins mainly manifests as Cl(-) transport, which is related to the binding free energies of chloride ions. Therefore, the influence of a mutation on ClC function can be studied by investigating the mutational effect on the binding free energies of chloride ions. The present study provides quantitative and systematic investigations on the influences of residue mutations on the electrostatic binding free energies in Escherichia coli ClC (EcClC) proteins, using all-atom molecular dynamics simulations. It was found that the change of the electrostatic binding free energy decreases linearly with the increase of the residue-chloride ion distance for a mutation. This work reveals how changes in the charge of a mutated residue and in the distance between the mutated residue and the binding site govern the variations in the electrostatic binding free energies and therefore influence the transport of chloride ions and conduction in EcClC. This work would facilitate our understanding of the mutational effects on transport of chloride ions and functions of ClC proteins and provide a guideline to estimate which residue mutations will have great influences on ClC functions.

The intramolecular hydroalkylation of ynoates (I) and (VI) leads to formation of cyclic enol ethers which are reduced to 2,5-substituted tetrahydrofurans and 2,6-substituted tetrahydropyrans.

A new method of determination total phosphorus in water based on nanoTiO2/C-K2S2O8 co-existed system photo-electrocatalytic oxidation graphite modified electrode has been described. TiO2/C electrode, which graphite surrounded by titanium dioxide, was prepared by sol-gel, dipping and coating process. The surface morphology of TiO2 coated on the graphite was characterized by scanning electron microscopy (SEM). The results indicate that the diameters of TiO2 particles rank from some nanometers to dozens. Meanwhile, TiO2/C was applied to decompose phosphine carboxylic acid copolymer (PCAC) by photo-electrocatalytic oxidation method. The optimum parameters determined by our experiments are as follows: the decomposition time is 10 min, the applied anode voltage is 8 V, the concentration of oxidant K2S2O8 is 0.02mol/L, alkaline solution has benefit to the decomposition of PCAC and the optimum pH is 8.5. This method is proved to be a better way to decompose organic phosphorous compared to national standard method by precision, recovery and comparison experiments.

A series of 2,6-bis(p-dihexylaminostyryl)anthracence derivatives having phenyl, styryl, and phenylethynyl groups at 9,10-positions (1-4) have been synthesized and their two-photon cross-sections were determined. Overall, the wavelengths of the longest wavelength absorption band and emission spectra increase with increase in the conjugation length and the electron withdrawing ability of the 9,10-substituents. All compounds show two-photon cross sections in the range of 740-3940 GM at 780-960 nm, which increase significantly by the donor and acceptor groups at 9,10-positions. In addition, Ph and phenylethynyl groups are better when compared to the styryl group at the 9,10-positions in terms of the two-photon action cross section. From a practical perspective, 1a, 2a-c, and 4b showed significant two-photon action cross-section and are most useful for applications that use two-photon excited fluorescence.

Surface photovoltage spectroscopy (SPS) was chosen to study the photovoltaic behavior of horseradish peroxidase (HRP), hemin and immobilized hemin (poly(NIPAAm/MBA/hemin)). Different photovoltaic behaviors were observed in these three systems. In air, similar SPS curves were found for HRP and poly(NIPAAm/MBA/hemin) with different response intensities. However, poly(NIPAAm/MBA/hemin) showed a wider changing range upon increasing the positive and negative bias to 1.0 V. The SPS of hemin showed a total different behavior when an external positive potential was applied. In vacuum, clearly different photovoltaic behaviors were found. Moreover, the response value decreased when HRP was exposed to O2, the SPS intensity was different from that in air, and could be altered by changing the external biases. On the other hand, the SPS could not be changed before and after poly(NIPAAm/MBA/hemin) was exposed to O2. These differences may result from different chemical microenvironments for hemin in HRP versus that in poly(NIPAAm/MBA/hemin). It could be concluded that H2O and O2 were important factors affecting the photovoltage response in HRP, but only H2O played this important role in poly(NIPAAm/MBA/hemin).