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BACKGROUND: The study of unstable atherosclerotic plaques is limited by the absence of ideal animal models to reproduce the plaque instability observed in humans. In this study, we attempted to develop a novel animal model for vulnerable atherosclerotic plaques using dehydrated ethanol lavage in rabbits fed a Western diet (WD). METHODS: A total of 30 New Zealand White (NZW) rabbits were randomized to 5 groups, including a control group with or without WD, a balloon injury with WD group, and an ethanol injury with or without WD group. Operations were conducted using the right common carotid artery as the target vessel. All animals were followed up for 3 months unless a vascular event occurred. Blood samples and carotid artery specimens were ultimately collected for analysis of atherogenesis. RESULTS: Compared to rabbits in which lesions were induced by balloon injury, those subjected to an ethanol lavage with high cholesterol diet showed progressive atherosclerotic lesions in all carotid artery segments, which were characterized by greater plaque burden, smaller minimum lumen area (MLA), and increased vulnerability as indicated by abundant macrophages, scattered smooth muscle cell (SMC) composition, higher matrix metalloproteinase-9 (MMP-9) expression in plaques, thinner fibrous cap thickness, and higher possibility of stroke event (50% vs. 0%). Meanwhile, the serum interleukin-1β (IL-1β) and monocyte chemoattractant protein-1 (MCP-1) levels in the ethanol injury group with a high-cholesterol diet were significantly higher than those in the balloon injury group after 3 months (all P

Bovine serum albumin (BSA) was induced to form cold-set gel by using glucono-δ-lactone (GDL) and sodium chloride (NaCl), and characteristics of the gel and its embedding potential to bioactive molecules were investigated. The results from texture analyzer indicated that hardness and springiness of BSA cold-set gel were improved by increasing GDL or NaCl, but the gel with lower concentration of GDL (1.0%) and NaCl (0.2 M) had better water holding capacity (WHC). GDL had a significant influence on storage modulus (G’) and loss modulus (G″) but it did not appear to be applicable to NaCl. Light transmittance at 500 nm and average particle size were used to characterize formation of BSA cold-set gel as pH values decreased, and the results suggested that BSA molecules had aggregated at the pH value of the gel point. Microstructure and fractal analysis from confocal laser scanning microscope (CLSM) further suggested that electrostatic and hydrophobic interaction played important roles in the formation of the cold-set gel and it could be deduced that structure and properties of the gel were closely related to the forces. BSA cold-set gel showed an excellent embedding performance to encapsulate bioactive molecules (used quercetin as representative), and achieved effective slow-release action, especially in simulated intestinal juice of pH 7.5. BSA cold-set gel may have important potential application in encapsulation, protection, delivery and controlled-release of some fragile bioactive components, so the research provides a theoretical basis for its application.

The biological responses of artificial biomaterials are affected strongly by its interfacial topography, especially from nano- to microscale. The structure controllability is essential for the design and synthesis of novel biomedical materials. Herein, the effect of soluble silk fibroin (SF) on the cathodic electrolytic deposition (ELD) behavior of octacalcium phosphate (OCP) coating is studied. It is observed that the addition of soluble SF does not change the inorganic phase of the coating (OCP), but it has a remarkable effect on the microstructure of the deposited coating. As a result, the OCP/SF composite coating possessed a micro/nano multilevel structure is finely constructed on titanium implant by using ELD technology. Such OCP/SF composite coating significantly promotes preosteoblast cells adhesion, spreading and proliferation. In general, effects have been made to produce an in-depth understanding of protein incorporated ELD technology to extend its application in the biomedical field. It provides a promising strategy to design and synthesize biomaterials with specific biomimetic structures and functions.

Sn-based N-doped carbon composites (Sn–CN) were simply fabricated via a one-pot thermal reaction. This experiment uses SnCl4·5H2O, resorcinol, formaldehyde and melamine as raw material. In order to...

The influences of solution cooling on the microstructures, mechanical properties and hot corrosion resistance of a nickel-based superalloy are researched. It is found that the mechanical properties and hot corrosion resistance are greatly influenced by the solution cooling methods including furnace-cooling (FC), water-cooling (WC) and air-cooling (AC). For the FC superalloy, large amount of coarse γ′′ (Ni3Nb) and γ′ (Ni3Al) phases precipitate from the matrix, and δ (Ni3Nb) phase preferentially precipitates on grain boundaries. Besides, compared with the WC and AC superalloys, the ultimate tensile strength, yield strength and micro-hardness of the FC superalloy are higher, but the elongation to fracture is lower. Additionally, the hot corrosion behavior can be well described by the sulfidation-oxidation model and the alkaline-base melting model. Furthermore, the FC superalloy has the best hot corrosion resistance among the three solution cooled superalloys

Purpose To establish an environment-induced dry eye model in rabbits using a controlled drying system (CDS). Methods Rabbits were randomly divided into two groups. The rabbits in the dry group were housed in the CDS, in which the relative humidity, airflow, and temperature were controlled at 22% ± 4%, 3 to 4 m/s, and 23°C to 25°C for 14 days. The rabbits in the control group were housed in a normal environment at the same time. A Schirmer test, fluorescein staining, and lissamine green staining were performed. On day 14, the eyeballs and lacrimal glands were processed for evaluating the corneal epithelial thickness, inflammatory cell infiltration index, goblet cell density, and expression of the MUC5AC protein and caspase-3 protein. The mRNA expression of the involved inflammatory genes was analyzed. Results The CDS was able to maintain a dry environment, in which the tear production decreased, and the ocular surface staining increased over time in the rabbits. In the dry group, the corneal epithelium became thinner, inflammatory cells were noted, goblet cells and MUC5AC proteins decreased, and the increased levels of caspase-3 proteins and inflammatory cytokines were observed in the ocular surface tissues and lacrimal glands. Conclusions This CDS could create a dry environment, in which the rabbits exhibited a pathological change in dry eye similar to that in humans. Translational relevance This model would be helpful in offering a platform to identify and test candidate therapies for environment-induced dry eye and to explore its underlying mechanisms.

The tunable photoluminescent materials has drawn extensive attention in recent years. The position of the substituents tuned the luminescent materials are one of attractive methods. Herein, we present a feasible and facile strategy to achieve a 4-amino-1,2,4-1H-triazole-based organic materials. A set of compounds based on 4-amino-4H-1,2,4-triazole group, namely, x,x'-(4-amino-4H-1,2,4-triazole-3,5-diyl)dianiline [x ​= ​2 (1), x ​= ​3 (2), x ​= ​4 (3)] (the formulas are C14H14N6, C14H14N6 and C14H16N6O for compounds 1–3, respectively), were obtained. The title compounds 1–3 have been characterized by IR, UV–Vis, element analysis (EA), single crystal X-ray diffraction, and powder X-ray diffraction (PXRD). In these compounds, a plenty of hydrogen bonds (C/N–H⋯O/N) and C–H … π can be obviously found. The order of the packing interactions is represented as the following: 2 ​> ​3>1. The Hirshfeld surface analyses reveal that the contribution order of the H⋯H bond contacts in compounds 1–3 is listed: 2 ​> ​3>1, which is in a good agreement with that of the stacking interactions. The solid-state luminescent spectra of 1–3 show that the emission maxima are observed at 404, 377 and 457 ​nm, respectively, where the order of the peaks is represented as 3 ​> ​1>2. The Hirshfeld surface analyses show that the contribution order of the C⋯H/H⋯C close contacts is listed: 3 ​> ​1>2, which is in a good accordance with that of the fluorescent maxima.

Graphene, whose structure is composed of a single-atom-thick sheet of sp2-hybridized carbon atom, provides large specific surface area, excellent mechanical and chemical properties. In this paper, reduced graphene oxide/carbon nanotube (rGO/CNT) composite, which had superior electrochemical performance, was synthesized via a facile, handy and cheap method. Electrochemical tests showed that rGO/CNT composite that the weight ratio of graphene oxide (GO) to CNTs is 7.5 to 1 exhibited the specific capacitance was 346.84 F/g at the current density of 2 A/g in 1 M H2SO4. The good performance of rGO/CNT composite was ascribed to huge surface area of rGO and homogeneous distribution of CNT, which prevented the aggregation of rGO sheets, increased the path of electron circulation and speeded up the electrolyte penetrating into the materials. Therefore, rGO/CNT composite had great potential on supercapacitors.

A set of compounds based on 4-amino-4H-1,2,4-triazole group, namely, 4,4′-(4-amino-4H-1,2,4-triazole-3,5-diyl)dibenzoic acid (1), 4,4′-(4-amino-4H-1,2,4-triazole-3,5-diyl)dianiline (2), 4,4′-(4-amino-4H-1,2,4-triazole-3,5-diyl)diphenol (3), were obtained through reacting different aromatic nitrile and hydrazine under the solvothermal conditions, respectively. The title compounds 1–3 have been characterized by IR, UV–Vis, 1H NMR, 13C NMR, element analysis (EA), single crystal X-ray diffraction, and powder X-ray diffraction (PXRD). In these compounds, a plenty of hydrogen bonds (C/N–H⋯O/N) and C H∙∙∙π can be obviously obtained, through which a three-dimensional framework will be constructed. The solid-state luminescent spectra of 1–3 show that the emission maxima are observed at 398, 464 and 402 nm, respectively. The order of maximal peaks is 1

The grain growth behaviors of a nickel-based superalloy after full recrystallization are investigated by hot compression test plus annealing treatment. Electron backscattered diffraction technology (EBSD) is utilized to analyze the grain boundary features. It is found that the annealing parameters greatly affect the average grain size, and annealing twin boundaries, including ∑3, ∑9, and ∑27 boundaries. The fully-recrystallized grains can rapidly grow up at relatively high annealing temperatures with the increase of annealing time. Meanwhile, large fractions of annealing twin boundaries form at the initial stage of annealing treatment. However, with the further increase of annealing time, the content of annealing twins slightly drops due to the migration of grain boundaries or twin boundaries. When the annealing temperature is increased, the shape of annealing twin is apparently lengthened while the number of annealing twin sharply decreases. In addition, the kinetics model for grain growth after full recrystallization is established and validated by the experimental observations.

A set of compounds based on 4-amino-4H-1,2,4-triazole group, namely, x,x'-(4-amino-4H-1,2,4-triazole-3,5-diyl) diphenol [x ​= ​2 (1), x ​= ​3 (2), x ​= ​4 (3)], were obtained through reacting a set of cyano-phenol and hydrazine under the solvothermal conditions, respectively. The title compounds 1–3 have been characterized by IR, element analysis (EA), single crystal X-ray diffraction, and powder X-ray diffraction (PXRD). A lot of hydrogen bonds (C/N/O–H⋯O/N) and C–H … π can be clearly observed in these compounds. It surprisedly occurs the presence of trans- and cis-conformation for compounds 3. The increasing order of the dihedral angles between the phenyl and triazole-yl rings is 1 ​ ​2>3. The luminescent maximal peaks decrease with the diminution of hydroxylic steric effects. The Hirshfeld surface analyses reveal that the contribution order of the O⋯H/H⋯O contacts in compounds 1–3 is listed: 1 ​

The present study was designed to develop a novel method for identifying significant pathways associated with human hypertrophic cardiomyopathy (HCM), based on gene co-expression analysis. The microarray dataset associated with HCM (E-GEOD-36961) was obtained from the European Molecular Biology Laboratory-European Bioinformatics Institute database. Informative pathways were selected based on the Reactome pathway database and screening treatments. An empirical Bayes method was utilized to construct co-expression networks for informative pathways, and a weight value was assigned to each pathway. Differential pathways were extracted based on weight threshold, which was calculated using a random model. In order to assess whether the co-expression method was feasible, it was compared with traditional pathway enrichment analysis of differentially expressed genes, which were identified using the significance analysis of microarrays package. A total of 1,074 informative pathways were screened out for subsequent investigations and their weight values were also obtained. According to the threshold of weight value of 0.01057, 447 differential pathways, including folding of actin by chaperonin containing T-complex protein 1 (CCT)/T-complex protein 1 ring complex (TRiC), purine ribonucleoside monophosphate biosynthesis and ubiquinol biosynthesis, were obtained. Compared with traditional pathway enrichment analysis, the number of pathways obtained from the co-expression approach was increased. The results of the present study demonstrated that this method may be useful to predict marker pathways for HCM. The pathways of folding of actin by CCT/TRiC and purine ribonucleoside monophosphate biosynthesis may provide evidence of the underlying molecular mechanisms of HCM, and offer novel therapeutic directions for HCM.

Pak choi ( Brassica rapa subsp. chinensis ) is a leafy vegetable that is widely available in Asia and consumed in rising quantities in Europe. Pak choi contains high levels of secondary plant metabolites, such as carotenoids, chlorophylls, glucosinolates, phenolic compounds, and vitamin K, which are beneficial for humans if consumed on a regular basis. The evaluation of the genotype-induced variation of secondary plant metabolites revealed that the cultivar ‘Amur’ contained the highest concentration of secondary plant metabolites. Furthermore, steaming retained more chlorophylls, glucosinolates, phenolic acids and flavonoid compounds than boiling. In contrast, both domestic cooking methods – boiling, and steaming – reduced the formation of glucosinolate breakdown products, especially the undesired epithionitriles and nitriles but less of the health-beneficial isothiocyanates.

Rationale and Objectives Using lower tube voltage can reduce the exposure to radiation and the dose of contrast agent. However, lower tube voltage is often linked to more noise and poor image quality, which create a need for more effective technology to resolve this problem. To explore the feasibility of coronary computed tomographic angiography (CCTA) in patients with obesity at low tube voltage (100 kV) and low contrast agent concentration (270 mg/mL) using iterative reconstruction. Materials and Methods A total of 48 patients with body mass index greater than 30 kg/m 2 were included and randomly divided into two groups. Group A received a traditional protocol (iopromide 370 mg/mL + 120 kV); group B received a protocol with low tube voltage (100 kV), low contrast agent concentration (270 mg/mL), and iterative reconstruction. The effective dose (ED), average attenuation values, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), the figure of merit (FOM), image quality scores, and the total iodine intake were compared. Results No significant differences in average CT attenuations, SNR, CNR, and subjective scores were noticed between the two groups ( P > 0.05), whereas the FOM of group B was significantly higher than that of group A. Effective radiation dose, total iodine, and iodine injection rate in group B were lower than those of group A ( P 0.01). Conclusions In patients with obesity, isotonic contrast agent with low iodine concentration and low-dose CCTA were feasible. Substantial reduction in radiation dose and the iodine intake could be achieved without compromising the image quality.

Three complexes, [3RBzIQl]2[Cu(mnt)2] (mnt2− = maleonitriledithiolate; [3RBzIQl]+ = 1-(3′-R-benzyl)isoquinolinium, R = Cl (1), I (2) or NO2 (3)), have been prepared and characterized by spectroscopic and physicochemical methods as well as by X-ray crystallography. The [Cu(mnt)2]2− anions formed a 1D chain in complex 1, a dimer in 2 and a sheet structure in 3 through C···N and/or N···N interactions. The neighboring dimers of the cations arranged in a boat-type pattern stack into columns through weak π···π, Cl···π or O···π, C–H···π interactions. The anions and cations stack together into a columnar structure with a ···A–CC–A–CC–A··· sequence. The magnetic susceptibilities measured in the temperature range 2.0–300 K reveal that complex 1 undergoes a change from weak ferromagnetic to antiferromagnetic exchange around 132 K, while 2 shows antiferromagnetic behavior and 3 shows a weak ferromagnetic interaction when the temperature is lowered.

Hot deformation behaviors of two pre-treated nickel-based superalloys are investigated over wide ranges of strain rate and temperature. Based on the theory of dynamic material model (DMM), the processing maps are developed and correlated with the deformed microstructures. The effects of pre-treatment, including water-cooling and furnace-cooling pre-treatments, on the hot deformation behavior and processing maps are discussed in detail. It is found that the hot deformation behavior and processing map of the aged superalloy are sensitive to pre-treatment. The peak stress of the aged superalloy after furnace-cooling pre-treatment is larger than that after water-cooling pre-treatment. Considering the coupled effects of deformation temperature, strain and strain rate, the phenomenological constitutive models of two pre-treated nickel-based superalloys are established. Meanwhile, the flow instability domains of the aged superalloy after furnace-cooling pre-treatment are narrower than those after water-cooling pre-treatment. At the true strain of 0.6, the flow instability domain of the aged superalloy after water-cooling pre-treatment is (920–1010 °C, 0.1–1s−1), while that after furnace-cooling pre-treatment is (930–970 °C, 0.1–1s−1). Additionally, the dynamic recrystallized grain size of the studied superalloy after furnace-cooling pre-treatment is smaller than that after water-cooling pre-treatment.

The incidence of ischemic stroke in patients with diabetes is increasing. While brachial-ankle pulse wave velocity (BaPWV) and ankle-brachial index (ABI) are known to be associated with ischemic cardiovascular and cerebrovascular diseases, whether these measures predict the risk of ischemic cerebrovascular disease in diabetic patients remains unclear. 117 patients with type 2 diabetes were enrolled in this study. According to the results of head magnetic resonance imaging, the patients were divided into a diabetes-only group (n = 55) and a diabetes and ischemic stroke group (n = 62). We then performed ABI and BaPWV examinations for all patients. Compared with the diabetes-only group, we found decreased ABI and increased BaPWV in the diabetes and ischemic stroke group. Multivariate logistic regression analyses revealed that BaPWV and ABI were risk factors for ischemic stroke in patients with type 2 diabetes. Our findings indicate that decreased ABI and increased BaPWV are objective indicators of increased risk of ischemic stroke in patients with type 2 diabetes.

Two new molecular solids, [4FBzIQl][Ni(mnt)2](1) and [4FBzIQl]2[Cu(mnt)2](2) ([4FBzIQl]+ = [1-(4′-fluorobenzyl)isoquinolinium; mnt2− = maleonitriledithiolate) have been obtained by complexing of the [M(mnt)2]n− (M = Ni(III) or Cu(II), n = 1 or 2) anion with [4FBzIQl]+ cation. Single-crystal structural analysis reveals that both molecular metals crystallize in the triclinic space group P-1. The [Ni(mnt)2]− anions of 1 form a column by short C⋯N and C⋯C interactions between the cyano groups of the anions, while two adjacent [Cu(mnt)2]2− anions of 2 form a dimer through S⋯S interaction. The neighboring cations form a dimer or 2D layered structure through C H⋯F hydrogen bonds, F⋯F interactions, and π⋯π stack interactions. The anions and cations stack alternately into a 1D column through C H⋯N, π⋯π or/and C H⋯S, C HCu interactions. Magnetic susceptibility measurements in the temperature range 2–300 K reveal that 1 exhibits a characteristic of two spin-gaps around 103.8 K and 7.5 K, respectively, while 2 shows a change of magnetic exchange from weak ferromagnetic to antiferromagnetic interaction around 43.9 K when the temperature is lowered.

Investigating the ratcheting behavior of magnesium alloys is significant for the structure’s reliable design. The uniaxial ratcheting behavior of AZ31B magnesium alloy is studied by the asymmetric cyclic stress-controlled experiments at room temperature. A modified kinematic hardening model is established to describe the uniaxial ratcheting behavior of the studied alloy. In the modified model, the material parameter m i is improved as an exponential function of the maximum equivalent stress. The modified model can be used to predict the ratcheting strain evolution of the studied alloy under the single-step and multi-step asymmetric stress-controlled cyclic loadings. Additionally, due to the significant effect of twinning on the plastic deformation of magnesium alloy, the relationship between the material parameter m i and the linear density of twins is discussed. It is found that there is a linear relationship between the material parameter m i and the linear density of twins induced by the cyclic loadings.

Three molecular solids, [2RBzIQl]2[Cu(mnt)2] (mnt2− = maleonitriledithiolate; [2RBzIQl]+ = 1-(2′-R-benzyl) isoquinolinium, R = F(1), Cl(2) and Br(3)), have been prepared and systemically investigated. The crystal structural analysis reveals that three molecular metals crystallize in the monoclinic with space group P21/c, and the [2RBzIQl]+ cations stack into an one-dimensional column through C H⋯π, π⋯π and C H⋯X (X = F or Cl) interactions while the [Cu(mnt)2]2− anions in 1 and 2 form a dimer by the side-to-side S⋯S, N⋯N and S⋯N interactions. The anions (A) and cations (C) are arranged alternatively into one 1D column for 1 and 2 and two 1D columns for 3 with a ⋯A CC A CC A⋯ sequence though C H⋯S, C H⋯π, C H⋯N or/and C H⋯Cu hydrogen bonds, and weak X⋯N (X = F, Cl), Br⋯S, Cu⋯N or/and π⋯π interactions. The magnetic susceptibilities measured in the temperature range 2.0–300 K reveal that 1 shows an antiferromagnetic behavior, while 2 and 3 exhibit a change of magnetic exchange from weak ferromagnetic to antiferromagnetic around 48 K upon the temperature is lowered.

A field experiment was conducted to study the effect of biochar amendment (0, 2.5, 5, 10, 20, 30 and 40 t·ha− 1) on rapeseed and sweet potato yields, aggregate particle size distribution, aggregate stability, soil organic carbon, total N content and C:N ratio in soil water stable aggregate under a rapeseed–sweet potato rotation system in upland red soil in Jiangxi Province of southern, China. The results were as follows: compared with control treatment (CK), when the amount of biochar was 40 t·ha− 1, rapeseed and sweet potato yields were increased by 36.02% and 53.77% respectively; the soil water stable aggregate (> 0.25 mm) in the 0–15 cm soil layer had a remarkable increase than other treatments, especially the macroaggregate with particle size larger than > 2 mm. In the rapeseed harvest season, the mean weight diameter of soil water stable aggregate was enhanced by 28.02% compared to CK with the application rate of biochar being 40 t·ha− 1. A significant increment in soil organic carbon, total N and C:N ratio was observed in the > 2 mm, 2–0.5 mm, 0.5–0.25 mm and

Creep-aging forming, combining both the aging treatment and forming process, has recently drawn much attention of researchers. In this study, the effects of creep-aging processing on the corrosion resistance of an Al–Zn–Mg–Cu alloy are studied. Results show that the corrosion resistance of the studied Al–Zn–Mg–Cu alloy is sensitive to creep-aging processing parameters (creep-aging temperature and applied stress). With the increase of creep-aging temperature, the corrosion resistance first increases and then decreases. Increasing the applied stress can deteriorate the electrochemical corrosion resistance and improve the exfoliation corrosion resistance. The creep-aging processing can change the size and distribution of precipitates in the aluminum matrix, which significantly affects the corrosion resistance. The discontinuous grain boundary precipitates and narrow precipitate-free zones can enhance the corrosion resistance.

The backward Lagrangian stochastic (BLS) model and open-path tunable diode laser (OPTDL) analyzer were used to monitor ammonia (NH3) emissions from urea applied to winter wheat in the North China Plain. The high-temporal resolution measurements of ammonia concentrations provided an opportunity for estimating the diel patterns of ammonia emissions, as well as valuable information about the factors that influence NH3 emissions. The results showed both large diel variability and daily variability in NH3 volatilization, with NH3 emissions highest during the daytime. The diel pattern of ammonia volatilization depended mainly on the diel variation of wind speed and soil temperature, while the overall pattern of NH3 loss was strongly affected by soil moisture content, soil NH4 +-N concentration, wind speed and soil temperature. At the end of the measurement period, the cumulative NH3 loss was 12.21–16.43 kg N ha−1, calculated based on different time scale average Q BLS. Due to sensitivity of the OPTDL analyzer, the estimated total ammonia loss was still doubtful in this study.

The dynamic recrystallization (DRX) behavior of a typical nickel-based superalloy is investigated by the hot compression tests. Based on the conventional DRX kinetics model, the volume fractions of DRX are firstly estimated. Results show that there is an obvious deviation between the experimental and predicted volume fractions of DRX when the forming temperature is below 980 °C, which is induced by the slow dynamic recrystallization rate under low forming temperatures. Therefore, the segmented models are proposed to describe the kinetics of DRX for the studied superalloy. Comparisons between the experimental and predicted results indicate that the proposed segmented models can give an accurate and precise estimation of the volume fractions of DRX for the studied superalloy. In addition, the optical observation of the deformed microstructure confirms that the dynamically recrystallized grain size can be well characterized by a power function of Zener–Hollumon parameter.

Due to their excellent properties, nickel-based superalloys are extensively used in critical parts of modern aero engine and gas turbine. The hot deformation behaviors of a typical nickel-based superalloy are investigated by hot compression tests with strain rate of (0.001–1) s−1 and forming temperature of (920–1040) °C. Results show that the flow stress is sensitive to the forming temperature and strain rate. With the increase of forming temperature or the decrease of strain rate, the flow stress decreases significantly. Under the high forming temperature and low strain rate, the flow stress–strain curves show the obvious dynamic recrystallization. Based on the stress–dislocation relation and kinetics of dynamic recrystallization, a two-stage constitutive model is developed to predict the flow stress of the studied nickel-based superalloy. Comparisons between the predicted and measured flow stress indicate that the established physically-based constitutive model can accurately characterize the hot deformation behaviors for the studied nickel-based superalloy.

A viable method—open-path tunable diode laser absorption spectroscopy (OPTDL) in conjunction with a backward Lagrangian stochastic (bLS) dispersion model—has been used for micrometeorological monitoring of ammonia fluxes. In this technique, the gas concentration measured with the OPTDL sensor is used to infer the surface emission rate with the aid of dispersion model calculations. On the basis of numerous assessment experiments and field trials, several beneficial strategies for using the OPTDL technique properly to monitor atmospheric NH3 concentrations in the field have been summarized. Theoretically, the location of the concentration measurement can be anywhere in the emission plume, but in practice, the concentration measurement position must be carefully selected to avoid making measurements which are on the periphery of the downwind plume or are affected by obstructions. To obtain accurate estimates, periods with low friction velocity or extreme atmospheric stability, where Monin–Obukhov similarity theory-based relationships are invalid, or unrepresentative estimates due to unsuitable wind direction, should be excluded. A validation experiment showed that there was no significant difference between the ammonia emission rates obtained by the micrometeorological mass balance method and those obtained by the bLS model combined with the OPTDL technique. This study also indicated the potential of the bLS and OPTDL technique for investigation of diurnal emission patterns and environmental influences.

A backward Lagrangian stochastic (BLS) model for estimating ammonia emission in the field, utilizing data from ammonia concentration measurements by the open-path tunable diode laser method, was assessed by comparing it with the benchmark provided by simultaneous monitoring by the micrometeorological mass balance (MMB) technique. The results indicated that after rejecting data with u* ≤ 0.15 m s−1 or |L| < 10 m, the ammonia emissions derived by the BLS model were very similar to those by MMB (regression gradient = 0.966, R2 = 0.959). The BLS model was also compared with the static chamber (SC) method of monitoring changes in gas concentration (enrichment/depletion) over time; it was found that these methods yielded significantly different results for both diurnal ammonia fluctuations and total ammonia loss. The results also showed that the mean time had little effect on the accuracy of the BLS method, but a short averaging time was preferable when investigating diurnal change of ammonia emissions.

The experiment adopted the method of cultivating Hydrilla verticillata and algae in coexistence systems to study the inhibitory effect of Hydrilla verticillata on planktonic algae in eutrophic water. The results showed that allelopathic and competition of nutrition inhibitory effect were both affect the inhibition of Hydrilla verticillata on planktonic algae at initial concentration of 105 cells·mL-1, and the highest inhibition ratio on was 79% at undernutrition condition; opposite, allelopathic inhibitory effect played a major role at nutritional sufficiency, the highest inhibition ratio was 39%. Hydrilla verticillata played a role of “promoting with low biomass while inhibiting with high biomass” on planktonic algae, the optimal biological dosage of Hydrilla verticillata on inhibiting planktonic algae at initial concentration of 105 cells·mL-1 was 12g·L-1. Hydrilla verticillata allproduced inhibitory effect on planktonic algae at different initial concentrations, and the greater the initial concentration of planktonic algae, the higher the inhibition ratio of Hydrilla verticillata on planktonic algae.

The mechanisms underlying tolerance to B-toxicity in plants are still controversial. Our previous studies indicated that B-toxicity is mainly limited to leaves in Citrus and that alternations of cell-wall structure in vascular bundles are involved in tolerance to B-toxicity. Here, miRNAs and their expression patterns were first identified in B-treated Citrus sinensis (tolerant) and C. grandis (intolerant) leaves via high-throughput sequencing. Candidate miRNAs were then verified with molecular and anatomical approaches. The results showed that 51 miRNAs in C. grandis and 20 miRNAs in C. sinensis were differentially expressed after B-toxic treatment. MiR395a and miR397a were the most significantly up-regulated miRNAs in B-toxic C. grandis leaves, but both were down-regulated in B-toxic C. sinensis leaves. Four auxin response factor genes and two laccase (LAC) genes were confirmed through 5′-RACE to be real targets of miR160a and miR397a, respectively. Up-regulation of LAC4 resulted in secondary deposition of cell-wall polysaccharides in vessel elements of C. sinensis, whereas down-regulation of both LAC17 and LAC4, led to poorly developed vessel elements in C. grandis. Our findings demonstrated that miR397a plays a pivotal role in woody Citrus tolerance to B-toxicity by targeting LAC17 and LAC4, both of which are responsible for secondary cell-wall synthesis.

Phosphate-manganese, tannic acid and vanadium conversion coatings were proposed as an effective pre-treatment layer between electroless Ni-P coating and AZ91D magnesium alloy substrate to replace the traditional chromate plus HF pre-treatment. The electrochemical results show that the chrome-free coatings plus electroless Ni-P coating on the magnesium alloy has the lowest corrosion current density and most positive corrosion potential compared with chromate plus electroless Ni-P coating on the magnesium alloy. These proposed pre-treatment layers on the substrate reduce the corrosion of magnesium during plating process, and reduce the potential difference between the matrix and the second phase. Thus, an electroless Ni-P coating with fine crystalline and dense structure was obtained, with preferential phosphorus content, low porosity, good corrosion-resistance and strengthened adhesion than the chromate plus electroless Ni-P.

2-Phenylethanol (2PE) is a prominent scent compound released from flowers of Damask roses (Rosa×damascena) and some hybrid roses (Rosa 'Hoh-Jun' and Rosa 'Yves Piaget'). 2PE is biosynthesized from l-phenylalanine (l-Phe) via the intermediate phenylacetaldehyde (PAld) by two key enzymes, aromatic amino acid decarboxylase (AADC) and phenylacetaldehyde reductase (PAR). Here we describe substrate specificity and cofactor preference in addition to molecular characterization of rose-PAR and recombinant PAR from R.×damascena. The deduced amino acid sequence of the full-length cDNA encoded a protein exhibiting 77% and 75% identity with Solanum lycopersicum PAR1 and 2, respectively. The transcripts of PAR were higher in petals than calyxes and leaves and peaking at the unfurling stage 4. Recombinant PAR and rose-PAR catalyzed reduction of PAld to 2PE using NADPH as the preferred cofactor. Reductase activity of rose-PAR and recombinant PAR were higher for aromatic and aliphatic aldehydes than for keto-carbonyl groups. Both PARs showed that (S)-[4-(2)H] NADPH was preferentially used over the (R)-[4-(2)H] isomer to give [1-(2)H]-2PE from PAld, indicating that PAR can be classified as short-chain dehydrogenase reductase (SDR).

The hepatoprotective potential of a protein-enriched fraction (PEF) isolated from the maggots of housefly (Musca domestica) was evaluated in rats against carbon tetrachloride (CCl4)-induced acute hepatic damage. Activities of serum aspartate aminotransferase and alanine aminotransferase increased by 4- and 13-fold induced by CCl4, were significantly inhibited by pretreatment with 50, 100 and 200 mg PEF/kg. The formation of malondialdehyde was also significantly decreased in PEF-treated group compared with CCl4-treated group. The treatments with PEF also elevated total protein levels significantly. These results were further supplemented by histopathological examination of liver sections. Hyperplasia of kupffer cells was observed after treatment with PEF (100 and 200 mg/kg). We conclude that PEF is effective in this model of liver damage.

A composite optical waveguide (OWG) composed of a 10-18nm thick titanium dioxide (TiO(2)) film sputtered on a conventional K(+)-doped optical waveguide was first applied to detect transient absorption of organic dyes in ultrathin polymer films upon excitation with ns laser. The thickness of the TiO(2) film considerably affected the relative sensitivity of the composite OWG. The composite OWG with 10nm thick TiO(2) gave much stronger transient absorption for 30-415nm thick polymer films containing organic dyes than that with 18nm TiO(2). Transient absorption of phthalocyanine and spiropyran in 20-135nm thick polymer films was detected 3-20 times more sensitively by the composite OWG with 10nm TiO(2) than the conventional K(+)-doped OWG which showed a 150-fold sensitivity as compared with the usual normal incidence method. The relative sensitivity of the composite waveguide was also affected by the thickness and refractive index of polymers.

The reaction of heteroaroyl-substituted heterocyclic ketene aminals with 2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl azide was investigated and a series of potential bioactive compounds, 1-glucopyranosyl-4-heterocyclic-5-heteroaryl-1,2,3-triazoles, were obtained in good yields. Both the reaction rate and the yield were strongly affected by the heteroaryl and heterocyclic groups. In order to improve their water solubility, the deprotection of 1-glucopyranosyl-4-heterocyclic-5-heteroaryl-1,2,3-triazole was carried out. © 2002 Wiley Periodicals, Inc. Heteroatom Chem 13:242–247, 2002; Published online in Wiley Interscience (www.interscience.wiley.com). DOI 10.1002/hc.10023

Two-step stress-aging tests, as well as pre-treatment plus stress-aging experiments, are performed on a 7075 aluminum (Al–Zn–Mg–Cu) alloy. Influences of stress-aging parameters on mechanical behavior and fracture mechanism are investigated through uniaxial tensile test and fracture morphology analysis. It is revealed that the stress-aging dramatically influences the mechanical properties and fracture characteristics of the studied alloy, which is contributed to the sensitivity of microstructures to stress-aging. When the alloy undergoes two-step stress-aging, the ultimate tensile strength and yield strength first increase and then decrease with the increased first step stress-aging temperature, while the elongation first decreases and then increases. For the retrogression pre-treated plus stress-aged alloy, the yield strength first increases and then drops with the increased retrogression pre-treatment time, while the ultimate tensile strength almost remains stable. Furthermore, the elongation continuously increases with the increased retrogression pre-treatment time. The observation of fracture morphology indicates that the dimple-type intergranular fracture is the main fracture mechanism for the two-step stress-aged and retrogression pre-treated plus stress-aged alloys.

Two new soluble bifunctional polymeric ligands ( R , R )- 4 and ( R , R )- 5 have been prepared via the direct condensation reaction of ( R )-3,3′-diformyl-1,1′-bi-2-naphthol ( R )- 1 with ( R )-5,5′-diamino BINAP ( R )- 2 and with ( R )-5,5′-diamino BINAPO ( R )- 3 , respectively. The different types of catalytic centers, BINOL and BINAP or BINAPO, were alternatively organized in a regular chiral polymer chain. Both polymeric ligands were found to be effective in the addition of diethylzinc to benzaldehyde either in the presence or in the absence of Ti(OPr i ) 4 with different enantioselectivities. ( R , R )- 4 /Ti(IV) catalyst, which showed similar efficiency to the parent catalyst BINOL/Ti(IV), was more enantioselective than ( R , R )- 5 /Ti(IV). ( R , R )- 4 was also found to be highly effective in the Ru(II)-catalyzed asymmetric hydrogenation of 2-arylacrylic acids. The results demonstrated that the use of the co-polymer catalyst rather than a mixture of monomer catalysts not only simplified the recycling of the catalyst, but also improved the enantioselectivity and/or the activity in some cases.

Novel dendritic chiral BINOL ligands have been synthesized through coupling of MOM-protected 3,3′-dihydroxymethyl-binaphthol with Frechet-type polyether benzyl bromide dendrons followed by deprotection of the MOM groups using TsOH. These dendritic chiral BINOL ligands were found to be effective in the enantioselective addition of diethylzinc to benzaldehyde both in the presence and absence of Ti(O-iso-Pr)4. The enantioselectivity decreased with increasing generation in both cases. In the latter case, the dendritic chiral BINOL ligands showed much higher catalytic activity and enantioselectivity than BINOL.

A new type of chiral dendritic ligands with 2,2′-bis(diphenylphosphino)-1,1′-binaphthyl (BINAP) located at the focal point of the dendrimer has been synthesized through the condensation reaction of 5-amino BINAP and Frechet-type poly (aryl ether) dendrons with carboxyl groups as the linker in high reaction yields, respectively. The ruthenium complexes of these dendritic ligands were found to be very efficient catalysts in asymmetric hydrogenation of 2-phenylacryclic acids as well as facile catalyst recycling.

A new type of amphiphilic PEG-bound BINAP ligand was synthesized through polycondensation of 5,5′-diamino BINAP ( 1 ), polyethylene glycol and terephthalyol chloride in the presence of pyridine. It was proven that ruthenium complex based on the new polymeric ligand was an effective catalyst for the asymmetric hydrogenation of prochiral α,β-unsaturated carboxylic acids in both ethyl acetate/water two-phase and in methanolic solvent systems. The activity and/or enantioselectivity in two-phase systems were observed to be higher than that in ethyl acetate or methanol–water homogeneous systems. The replacement of water with ethylene glycol increased the activity and enantioselectivity. The activity of the new catalyst was shown to be about 30 times higher in the two-phase hydrogenation of 2-(6′-methoxy-2′-naphthyl)-acrylic acid than the Ru(BINAP-4SO 3 Na) catalyst without the long hydrophilic polymer chain, which illustrated the importance of the amphiphilic structure of the polymeric ligand.

A series of potential bioactive compounds, 1-glucosyl-4-heterocyclyl-5-(p-substituted-phenyl)-1,2,3-triazoles , were synthesized. Highly stereoselective products were obtained in good yield. Primary activity screening showed that this type of N-glucosylic compound possessed antitumour and antiviral activities.

The solid state photochemical reaction of indole with 1,4-naphthoquinone yielded 5H-dinaphtho[2,3-a:-2′,3′-c]carbazole-6,11,12,17-tetrone (1) in addition to 2-(3-indolyl)-1,4-naphthoquinone (2) which was also the only product in the solution photoreaction. Solventless thermochemical reactions of indole with phenanthrenequinone in the presence or absence of zinc chloride gave 10-(1H-indol-3-yl)-9-phenanfhrenol (3) and 9,10-dihydro-9-(1H-indol-3-yl)-10-(3H-indol-3-ylidene)-9-phenanthrenol (4) or 10,10-di-1H-indol-3-yl-9(10H)-phenanthrenone (5), respectively. All of these products were only obtained in trace amount in corresponding solution reactions, and are different from the adduct 10-hydroxy-10-(1H-indol-3-yl)-9(10H)-phenanthrenone (6) obtained in the solution photoreaction. A possible mechanism for formation of 4 and 5 is described in terms of electron pair donor/acceptor complexation.

A K+ ion-exchanged glass optical waveguide (OWG) was combined with an Ag+ ion-exchanged glass OWG on one substrate by tapered velocity coupling to obtain a low loss and highly sensitive ion-exchanged OWG system. The relative sensitivity of the Ag+-doped region was more than 1000 times per unit length (the reference here being spectroscopic measurements with normal incidence of monitoring light). The attenuation of the guided light was 3—5 dB cm−1 at the highly sensitive part. Stability against heat and against UV-irradiation were investigated also.

Food safety is of extreme importance to human health. Vanillin and ethyl vanillin are the widely used food additives and spices in foods, beverages, cosmetics and drugs. The objective of the present work was to evaluate the impact of vanillin and ethyl vanillin on the activities of CYP2C9, CYP2E1, CYP3A4, CYP2B6 and CYP1A2 in human liver microsomes (HLM) in vitro, and impact on the activities of CYP1A2, CYP2C, CYP3A and CYP2E1 in rat liver microsomes (RLM) in vivo. The in vitro results demonstrated that vanillin and ethyl vanillin had no significant effect on the activity of five human CYP450 enzymes with concentration ranged from 8 to 128 μM. However, after rats were orally administered vanillin or ethyl vanillin once a day for seven consecutive days, CYP2E1 activity was increased and CYP1A2 activity was decreased in RLM. The in vivo results revealed that drug interaction between vanillin/ethyl vanillin and the CYP2E1/CYP1A2-metabolizing drugs might be possible, and also suggested that the application of the above additives in foods and drugs should not be unlimited so as to avoid the adverse interaction.

Antioxidant activity of the chitosan from the larvae of Musca domestica L. was evaluated in two different reactive oxygen species assays, and inhibitory effects against seven fungi were also tested. The results showed that the chitosan had scavenging activity for hydroxyl and superoxide radicals which were similar to that of ascorbic acid. Also the chitosan exhibited excellent antifungal activity, especially in the low concentration, it could significantly inhibit the growth of Rhizopus stolonifer. Besides, antiviral results demonstrated that the chitosan could effectively inhibit the infection of AcMNPV and BmNPV. These results suggested that the chitosan from the larvae of housefly could be effectively used as a natural antioxidant to protect the human body from free radicals and retard the progress of many chronic diseases. Furthermore, the chitosan with antiviral and antifungal activity might provide useful information for antiviral breeding technology of economic insect and development of plant pathological control.

A K+-doped glass optical waveguide (OWG) and an Ag+-doped glass OWG were combined on one substrate using tapered velocity couplers to realize OWG systems for surface spectroscopy with high sensitivity and low loss. The high sensitivity part (Ag+-doped region) was more than 1000 times sensitive compared with optical measurements with normal incidence of monitoring light.

In this paper, the space variability of soil total phosphorus and available phosphorus at the depths of 0-12 cm ,12-20cm ,20-30cm in the Taihu Lake region of rice soil was examined by using traditional statistics with geoststistics methods. The results showed that: total phosphorus content was reduce while the depths increasd, and available phosphorus content was first increased and then decreased with the depth increased. All three soil phosphorus coefficient of variation (57.53% -85.28%) far higher than the coefficient of variation available P (42.43% -64.42%), the semi-variable function of the variance variation C0 / (C0 + C) higher than 0.25, it indicate they have middle and weak correlation space and similar distance spatial structure .

The solid state photochemical reaction of indole with 1,4-naphthoquinone yielded 5H-dinaphtho[2,3-a:-2′,3′-c]carbazole-6,11,12,17-tetrone (1) in addition to 2-(3-indolyl)-1,4-naphthoquinone (2) which was also the only product in the solution photoreaction. Solventless thermochemical reactions of indole with phenanthrenequinone in the presence or absence of zinc chloride gave 10-(1H-indol-3-yl)-9-phenanfhrenol (3) and 9,10-dihydro-9-(1H-indol-3-yl)-10-(3H-indol-3-ylidene)-9-phenanthrenol (4) or 10,10-di-1H-indol-3-yl-9(10H)-phenanthrenone (5), respectively. All of these products were only obtained in trace amount in corresponding solution reactions, and are different from the adduct 10-hydroxy-10-(1H-indol-3-yl)-9(10H)-phenanthrenone (6) obtained in the solution photoreaction. A possible mechanism for formation of 4 and 5 is described in terms of electron pair donor/acceptor complexation.