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The goal of our work is to discover dominant objects in a very general setting where only a single unlabeled image is given. This is far more challenge than typical co-localization or weakly-supervised localization tasks. To tackle this problem, we propose a simple but effective pattern mining-based method, called Object Location Mining (OLM), which exploits the advantages of data mining and feature representation of pre-trained convolutional neural networks (CNNs). Specifically, we first convert the feature maps from a pre-trained CNN model into a set of transactions, and then discovers frequent patterns from transaction database through pattern mining techniques. We observe that those discovered patterns, i.e., co-occurrence highlighted regions, typically hold appearance and spatial consistency. Motivated by this observation, we can easily discover and localize possible objects by merging relevant meaningful patterns. Extensive experiments on a variety of benchmarks demonstrate that OLM achieves competitive localization performance compared with the state-of-the-art methods. We also evaluate our approach compared with unsupervised saliency detection methods and achieves competitive results on seven benchmark datasets. Moreover, we conduct experiments on fine-grained classification to show that our proposed method can locate the entire object and parts accurately, which can benefit to improving the classification results significantly. [ABSTRACT FROM AUTHOR]

Film cooling is a commonly used thermal protection technology for turbine airfoils. However, due to the counter-rotating vortex pair (CVP) generated by the interaction between the cooling jet and the mainstream, the coolant gradually breaks away from the wall, which is particularly evident at high blowing ratios. For the sake of improving the film cooling effectiveness (FCE) under high inlet temperature conditions, a novel film cooling structure (SerrTrench-VSS) that combines serrated trench film holes with shark skin-inspired V-shaped surface (VSS) is proposed. The RANS method and realizable k - ε model are used for the simulations. The flow characteristics, adiabatic FCE, and resistance loss are analyzed in detail when the blowing ratio (BR) is 0.5–1.5 and then compared with the traditional cylindrical film hole and transverse trench film hole. In addition, the impact of VSS height on the cooling performance is investigated and the best height of the structure is determined. The results show that the SerrTrench-VSS has better FCE. The serrated trench can destroy the CVP and improve the spanwise spreading ability of the coolant. Also, the VSS can converge the cooling jet downstream of the film hole toward the centerline, thereby improving its extension ability along the flow direction. In the studied range of blowing ratio, the SerrTrench-VSS has the best FCE, and the spanwise-averaged FCE increases by up to 10.50% when BR = 0.5. The empirical correlations between the globally-averaged FCE and the height ratio within the range of the present study are also given. For the serrated trench, the cooling jet has the best spanwise spreading and flow extension ability when the VSS height is 0.5 D. The proposed novel film cooling structure (SerrTrench-VSS) can effectively improve the FCE and provide feasible means for the efficient cooling of a turbine blade under practical conditions. [Display omitted] • A V-shaped surface structure inspired by shark skin was proposed for film hole cooling. • It can concentrate the downstream cooling jet and inhibit the counter-rotating vortex pairs. • The best height of the V-shaped surface structure was determined. • The best cooling effectiveness can be obtained by combining a serrated trench with this structure. • The globally-averaged film cooling effectiveness and the height ratio were empirically correlated. [ABSTRACT FROM AUTHOR]

Mist-assisted film cooling has exhibited great potential for efficient cooling of a turbine vane due to the vaporization of water droplets flowing with the air. To further improve the film coverage and cooling effectiveness, it is necessary to find a structure that allows the coolant flow to expand laterally and inhibits the separation of the coolant jet from the wall. Therefore, we propose in this work to study the influence of serrate structure on the cooling performance of trenched holes by examining the flow and heat transfer characteristics of the mist/air mixture. As water evaporation is involved in this process, the dry-bulb temperature may not be suitable for evaluating the film cooling performance. Therefore, a wet-bulb-temperature-based film cooling effectiveness (WFCE) is proposed. The results show that the included angle of serrate plays a significant role in WFCE. In addition, the area-average WFCE of the trenched holes increases first and then decreases as the blowing ratio increases. The concentration of mist and the diameter of droplets are found to be crucial for significantly affecting the WFCE. The relationship between the film cooling effectiveness and the contribution of mist is explicated by empirical correlation with the mist concentration and droplet diameter. The empirical correlation, especially the exponential increasing trend with the square root of mist concentration at a constant droplet diameter, provides the basis for further theoretical analysis of the mechanism of cooling effectiveness improvement. Under the practical condition, it is also proved that the serrated transverse trench structure and the addition of mist to the coolant air can improve significantly the film cooling performance for the turbine vane. • Influence of serrate structure on mist/air film cooling performance of trenched holes is studied. • Wet-bulb-temperature-based film cooling effectiveness (WFCE) is proposed and evaluated. • WFCE increases linearly with droplet diameter when mist concentration is given. • WFCE increases exponentially with square root of mist concentration at constant droplet diameter. • The cooling strategy is proved for turbine vane under practical condition. [ABSTRACT FROM AUTHOR]

• A vane model including double-wall structure and air/mist mixture. • Average temperature of blade surface drops substantially by 156∼174 k. • Distribution of Nusselt number at internal wall of chamber. • Total pressure loss coefficient of vane under real working conditions. • Thermal performance factor is introduced to evaluate the cooling characteristics. This paper establishes a comprehensive vane model which includes a double-wall cooling structure, with a C3X vane as the prototype and the air added with droplets as the coolant. The temperature of the vane, the trajectory of the evaporating droplets, the water vapor mass fraction on the vane surface, the distribution of the Nusselt number at the internal wall of the chamber, and the total pressure loss coefficient of the vane are calculated subsequently under real working conditions. The thermal performance factor is also introduced to evaluate comprehensively the cooling characteristics. It shows that when the coolant is air, the average surface temperature of the vane with double-wall cooling structure drops by 35 K; when a 10% mass fraction of air is replaced by droplets, the average temperature of the vane surface drops substantially by 156∼174 K. At the same time, it is found that a smaller droplet is conducive to the performance improvement. This work reveals a promising method of vane cooling design by using the proposed structure with impingement/film cooling and air/mist mixture, although the double-wall can relatively increase the total pressure loss. The total pressure loss of a vane with a double-wall structure is increased by 10.54% compared to the traditional vane. It is proved that the double-wall cooling structure and the addition of mist to the coolant air can improve significantly the thermal performance factor. As the mist concentration varies, the area-average temperature, the globally-averaged Nusselt number, and the thermal performance factor vary significantly, while the total pressure loss changes slightly. The relationship between the dimensionless area-average temperature and the contribution of mist (in terms of mist concentration and droplet diameter) is explicated. [ABSTRACT FROM AUTHOR]

In this work, the influence of several lip structures on the effectiveness of film cooling and the flow fields of transverse trenched holes at different blowing ratios (BRs) ranging from 0.5 to 2.0 is numerically investigated, using the Reynolds averaged Navier Stokes method with the realizable k - ε turbulence model. The trenches include the traditional transverse trench, the bevel trenches, and the fillet trenches. It shows that the trenched holes produce weaker counter-rotating vortex pairs, which can enhance the effectiveness of film cooling compared with the standard cylindrical film hole. It demonstrates that the lip structures can improve the effectiveness of film cooling of the trenches at low BRs, but it has a negative effect at high BRs. It is found that the lower lip structures have less influence on the effectiveness of film cooling at different BRs than the upper lip structures. It is also found that the upper part of the fillet structure employs the Coanda effect to make the coolant flow close to the wall, thereby improving the effectiveness of film cooling; while the lower part of the fillet structure is conducive to converting the coolant flow into a vertical jet, thereby improving the effectiveness of film cooling at low BRs. [ABSTRACT FROM AUTHOR]

• A new method of defining the velocity field in the coolant inlet is used to quantitatively investigate the effects of the coolant swirl intensity on the film cooling performance in the operating conditions of h series turbine vanes. • The critical value of the coolant vorticity to the transformation of film coverage is 20,000 /s. • When the coolant vorticity is 40,000 /s, the area-averaged film cooling effectiveness at the near field downstream of the film hole is 54 % higher than the non-swirling case. • With high blowing ratios and large vorticities, a stable flow field is formed, where the additional coolant vortex and induced vortex appear. • For high blowing ratios, with the increase of the vorticity, the momentum advantage of the coolant gradually transforms into the effectiveness advantage. Advanced H/J series heavy-duty gas turbines are widely equipped with film cooling to protect turbine blades. Previous studies have shown that coolant swirl has an important influence on film cooling performance. However, there are few studies on the quantitative analysis of the coolant swirl intensity because of the swirl generated by the specific structure, and most of the research was carried out at relatively low temperatures. In this paper, a new method of defining the velocity field in the coolant inlet is used to quantitatively investigate the coolant swirl intensity. A numerical study of the film cooling performance for the coolant jet with various swirl intensities is conducted in the operating conditions of H series turbine vanes. The effects of the blowing ratio and coolant vorticity on the vortex structure and mixing process of the flow field are investigated emphatically, and the mechanisms for the variation of the film cooling effectiveness are analyzed. The results show that the film cooling effectiveness is greatly improved with the swirling coolant jet at high blowing ratios. When Ω n =40,000 /s, the area-averaged (L = 5 D) film cooling effectiveness is 54 % higher than the non-swirling case. Ω n =20,000 /s is a critical value of the coolant vorticity. When Ω n >20,000 /s, the film coverage transforms significantly. Furthermore, the main vortical structures in a typical SJICF flow field with high blowing ratios and large vorticities are proposed. Compared with the non-swirling JICF, the additional coolant vortex and induced vortex appear in the SJICF. Under the influence of the two vortices, the coolant momentum is sacrificed for enhanced attachment to the wall resulting in the momentum advantage gradually transforming into the effectiveness advantage with the increase of the vorticity. [ABSTRACT FROM AUTHOR]

In this paper, a new multifunctional compound, 1,1′-(oxalylbis(4,1-phenylene))bis(1H-pyrrole-2,5-dione) (BVM), is grafted onto crosslinked polyethylene (XLPE) by radical-initiated grafting to play triple roles as a voltage stabilizer, space-charge inhibitor and crosslinking auxiliary and to achieve the purpose of comprehensively enhancing the DC dielectric properties of polymers while decreasing the type and number of additives. By analyzing the DC breakdown field strength, current density and space-charge distribution of the materials at different temperatures, it is demonstrated that BVM grafting can comprehensively and effectively enhance the electrical properties of the materials, with little dependence on temperature. The BVM molecule has two polar groups and an effective molecular structure that acts as a voltage stabilizer, thus enabling the introduction of dense, uniform, deeply trapped energy levels within the material to inhibit the space charge and to capture high-energy electrons to prevent damage to the material structure; however, the two functions do not affect each other. This is also consistent with first-principles calculations and quantum-chemical calculations. Gel content testing shows no effect on polymer crosslinking, even with a 27.8% reduction in the amount of the crosslinking agent di-isopropyl peroxide (DCP), which reduces the damage to the polymer's electrical resistance caused by the byproducts of DCP decomposition. Therefore, grafting multifunctional BVM compounds to improve the dielectric characteristics of polymers is a viable area of study in the development of high-voltage direct current (HVDC) cable materials. [ABSTRACT FROM AUTHOR]

Modern gas turbines use high-performance ribs to improve internal cooling performance. In this study, the aerothermal performance of a bio-inspired truncated rib arrangement with stepped length and height variations, proposed in our previous work, is systematically studied using the numerical simulation method and the rib structures are optimized using the response surface methodology. A square channel model is employed to simulate the flow of actual turbine blade, and the rhombus-patterned ribs are placed on the two channel sidewalls. The studied structural parameters include the length variation rate, height variation rate, and pitch distance. It is found that as the rib height decreases, heat transfer is enhanced while the pressure drop is decreased. In general, however, as the variation rates of height and length increase, both the heat transfer coefficient and flow loss increase. The correlations between the thermal performance factor and the three structural parameters are obtained from thirteen cases of aerothermal performance analysis, and the optimal structure of rhombus-patterned ribs is further obtained: Δ l / l 1 = 0.333, Δ e / e 1 = 0.167, and p / e 1 = 2.000. The geometric layout optimization of the novel ribs is important for providing higher thermal performance of the internal channel and hence efficient cooling of the turbine blades. • Rhombus-patterned rib structures are optimized to enhance turbine blade aerothermal performance. • The response surface methodology is used for optimizing the structural parameters. • The optimized parameters include length variation rate, height variation rate, and pitch distance. • The relationship between the thermal performance factor and these parameters are correlated. • The rhombus-patterned ribs are also suitable for application in many heat exchange devices. [ABSTRACT FROM AUTHOR]

This paper addresses semi-supervised semantic segmentation by exploiting a small set of images with pixel-level annotations (strong supervisions) and a large set of images with only image-level annotations (weak supervisions). Most existing approaches aim to generate accurate pixel-level labels from weak supervisions. However, we observe that those generated labels still inevitably contain noisy labels. Motivated by this observation, we present a novel perspective and formulate this task as a problem of learning with pixel-level label noise. Existing noisy label methods, nevertheless, mainly aim at image-level tasks, which can not capture the relationship between neighboring labels in one image. Therefore, we propose a graph-based label noise detection and correction framework to deal with pixel-level noisy labels. In particular, for the generated pixel-level noisy labels from weak supervisions by Class Activation Map (CAM), we train a clean segmentation model with strong supervisions to detect the clean labels from these noisy labels according to the cross-entropy loss. Then, we adopt a superpixel-based graph to represent the relations of spatial adjacency and semantic similarity between pixels in one image. Finally we correct the noisy labels using a Graph Attention Network (GAT) supervised by detected clean labels. We comprehensively conduct experiments on PASCAL VOC 2012, PASCAL-Context, MS-COCO and Cityscapes datasets. The experimental results show that our proposed semi-supervised method achieves the state-of-the-art performances and even outperforms the fully-supervised models on PASCAL VOC 2012 and MS-COCO datasets in some cases. [ABSTRACT FROM AUTHOR]

A field sampling method based on magnetic core–shell silica nanoparticles was developed for field sampling and the enrichment of low concentrations of pesticides in aqueous samples. The magnetic nanoparticles could be easily extracted from water samples by a custom-made magnetic nanoparticle collector. The recovery of 15 mg of magnetic particles from a 500 mL water sample was 90.8%. Mixtures of seven pesticides spiked into pure water and pond water were used as marker samples to evaluate the field sampling method. The average recoveries at three levels of spiking were in the range 60.0–104.7% with relative standard deviations <7.1%. The proposed method has good linearity with a correlation coefficient >0.9990 in the concentration range 0.5–15 μg L−1. The results of the analysis of a sample of poisoned pond water indicate that this method is fast, convenient and efficient for the field sampling and enrichment of pesticides in aqueous samples. [ABSTRACT FROM AUTHOR]

• A novel double-wall with composite swirl/film cooling structure was proposed. • The structure exhibited outstanding overall cooling effectiveness (OCE) in the simulated range. • The cooling performance at high blowing ratios were obtained and the OCE was sensitive to bi. • The empirical correlations obtained by nonlinear fitting were in good agreement with the simulations. • It provided a guidance for developing advanced gas turbine blades double-wall cooling structures. A novel double-wall with composite swirl/film cooling structure is proposed in this work to enhance the cooling effectiveness of contemporary gas turbine blades. The influence of different shaped chambers and Biot numbers on the overall cooling effectiveness (OCE) are investigated by Reynolds time-averaged Navier-Stokes simulations and conjugate heat transfer analysis. The results suggest that the proposed composite cooling configuration exhibits outstanding OCE in the simulated range. When the R m is 1.00 and the Biot number is 0.11, the OCE of the composite structure is improved by 8.92 % over the conventional double-wall structure, and the distribution is more uniform. In addition, the optimal flow and cooling performance of the composite swirl/film cooling structure at high R m conditions are obtained. The OCE is very sensitive to the variation of the Biot number. Finally, the empirical correlations obtained by the multivariate nonlinear regression fitting method are in good agreement with the simulations, with errors within 10 %. The results also provide important guidance for the development of advanced gas turbine blades double-wall cooling structures. [ABSTRACT FROM AUTHOR]

• Impact of double rows on air/mist film cooling is studied for the first time. • Sellers prediction model is appropriately modified for double rows. • Modified sellers method is proved to be more suitable for air/mist film cooling. • Air/mist film cooling effectiveness is accurately correlated by the modified model. Improving the multi-row film cooling effectiveness of turbine vanes and blades is becoming increasingly important, and the configuration design of the multi-row holes is becoming increasingly complex. This paper presents a simulation study of the air/mist film cooling characteristics on double-row-hole flat plates and makes predictions about spanwise-averaged cooling effectiveness using a modified Sellers superposition method. The effects of blowing ratio, row spacing, row arrangement, droplet diameter, and mist mass ratio on film cooling are systematically investigated. It is found that the injected mist improves the film cooling effectiveness under all operating conditions for the coolant air. The air/mist cooling is particularly effective at a blowing ratio of 1.25 or a row spacing of 5 D with the staggered two-row holes. The improvement in cooling effectiveness increases with increasing mass ratio or decreasing droplet diameter of the mist. Furthermore, the spanwise-averaged cooling effectiveness can be accurately predicted by modifying the classical Sellers superposition model. This study lays the foundation for accurately predicting the distribution of air/mist film cooling effectiveness of turbine vanes and blades, and helps to promote the development of practical air/mist film cooling technology. [ABSTRACT FROM AUTHOR]

The horizontal features of vehicle bottom and the vertical features of both sides of vehicle are selected, and the local features of gray scale and its gradient and variation, which are less affected by global gray scale, are extracted. The horizontal and vertical features of vehicle are fused respectively by applying weighted evidence theory, and the weight of each feature is adjusted according to different light intensity. For improving the realtimeness of identification, artificial fish swarm algorithm is applied, and a vehicle identification module is added to enhance the guiding ability of artificial fishes. Based on search results and further judgment by symmetric feature, the accurate positioning of front vehicle is realized. Experiment results show that the technique proposed can accurately identify front vehicles under different lighting conditions with good adaptability, accuracy and realtimeness. [ABSTRACT FROM AUTHOR]

Objectives: This study investigated the antibacterial, cytotoxicity, and mechanical properties of a dental adhesive modified with quaternary ammonium monomer ((2-acryloyloxyethyl)dimethyldodecylammonium bromide) and cross-linker (bis(2-acryloyloxyethyl)methyldodecylammonium bromide). Materials and methods: Monomer (M), cross-linker (C), or a combination of these (M + C) were incorporated into adhesive Adper Single Bond Plus (SB) in 5, 10, or 25% (as wt%). A colony-forming unit and MTT assays were used to evaluate antibacterial properties against Streptococcus mutans and cell viability. Resin-dentin beams (0.9 ± 0.1 mm2) were evaluated for micro-tensile bond strength (μTBS) after 24 h, 6 months, and 3 years. Hourglass specimens were evaluated for ultimate tensile strength (UTS) after 24 h, 1 week, and 6 months. Micro-hardness measurements after softening in ethanol were taken as an indirect assessment of the polymer cross-linking density. Kruskal-Wallis, one-way ANOVA, two-way ANOVA, and Student's t test were used for analysis of the antibacterial, cytotoxicity, μTBS, UTS, and hardness data, all with a significance level of p < 0.05. Results: 10%M and 25%M demonstrated a significant reduction in S. mutans relative to SB (p < 0.001). No differences in cytotoxicity were detected for any of the groups. After 6 months, no changes in μTBS were shown for any of the groups. After 3 years, all groups evidenced a significant decrease in μTBS (p < 0.05) except 5%M, 5%C, and 5%M + 5%C. All groups demonstrated either stable or significantly increased UTS after 6 months. Except for the cross-linker groups, a significant decrease in micro-hardness was shown for all groups after softening in ethanol (p < 0.05). Conclusions: A 5–10% of monomer may render the resin antibacterial without a compromise to its mechanical and bonding properties. Clinical relevance: Biomodification of a resin adhesive with an antibacterial monomer and cross-linker may help improve the life span of adhesive restorations. [ABSTRACT FROM AUTHOR]

• We propose a novel Hybrid CNN architecture to address the problem of sketch recognition. • S-Net extracts shape features, which is invariant for sketch rotation and transformation. • Hybrid CNN achieves state-of-the-art on sketch classification and sketch-based image retrieval tasks. • The classification accuracy is 84.42% and 82.74% on TU-Berlin and SketchX datasets, respectively. • The MAP of SBIR is 57.4% and 28.74% on SketchX and Flickr15K-Large datasets, respectively. With the popularity of touch-screen devices, it is becoming increasingly important to understand users' free-hand sketches in computer vision and human-computer interaction. Most of existing sketch recognition methods employ the similar strategies used in image recognition, relying on appearance information represented by hand-crafted features or deep features from convolutional neural networks. We believe that sketch recognition can benefit from learning both appearance and shape representation. In this paper, we propose a novel architecture, named Hybrid CNN, which is composed of A-Net and S-Net. They describe appearance information and shape information, respectively. Hybrid CNN is then comprehensively evaluated in the sketch classification and retrieval tasks on different datasets, including TU-Berlin, Sketchy and Flickr15k. Experimental results demonstrate that the Hybrid CNN achieves competitive accuracy compared with the state-of-the-art methods. [ABSTRACT FROM AUTHOR]

A rapid and sensitive gas chromatography with mass spectrometry method for the determination of venlafaxine in rat plasma has been developed and applied to a drug-drug interaction study of fluoxetine on pharmacokinetics of venlafaxine in rats. Rat plasma was spiked with 2% aqueous ammonia before subjected to preactivated C18 solid-phase extraction columns and eluted with methanol. No endogenous interferences were observed under optimal condition. The calibration curve was linear ( R2 = 0.9994) in the range of 10-1000 ng/mL. The quantification limit of venlafaxine in rat plasma was 10 ng/mL. The accuracy was in the range of 85-110%, and the extraction recovery was no less than 50%. Both the intra- and interday precision were 5.0-10.7%. The concentration-time curve showed that plasma concentrations of the coadministration group (group B) were higher than that of single dose group (group A). Both values of Cmax (0.069 mg/L) and AUC0→∞ (0.291 mg h/L) in group B were statistically greater than that of Cmax (0.046 mg/L) and AUC0→∞ (0.181 mg·h/L) in group A ( P < 0.05). The results indicated that a significant effect of fluoxetine was shown on the pharmacokinetics of venlafaxine, suggesting that drug-drug interactions are of concern for the treatment of depression with the combined use of venlafaxine and fluoxetine. [ABSTRACT FROM AUTHOR]

Antidepressant drugs are widely used in the treatment of different psychiatric disorders, as well as in conjunction with antipsychotics for the treatment of major depressive disorder. In this study, a simple and rapid ultrasound-assisted low-density solvent dispersive liquid–liquid microextraction (UA-LDS-DLLME) method was developed for the simultaneous determination of 12 new antidepressants (norfluoxetine, fluoxetine, fluvoxamine, agomelatine, mirtazapine, moclobemide, melitracen, N-desmethylmirtazapine, maprotiline, sertraline, citalopram, paroxetine) and 2 antipsychotics (clozapine and haloperidol) in human whole blood by gas chromatography–mass spectrometry (GC–MS). Different parameters affecting the UA-LDS-DLLME were optimized and the optimal conditions were as follows: 100 μL of toluene as extraction solvent, extraction pH 12 and 3 min of ultrasound stirring. Good linearity ( R 2 ≥ 0.991) was obtained at the concentration range of 15–1500 ng/mL for norfluoxetine, fluoxetine, fluvoxamine, melitracen, maprotiline and citalopram, and 5–500 ng/mL for agomelatine, mirtazapine, moclobemide, N-desmethylmirtazapine, sertraline, paroxetine, clozapine and haloperidol. The intra-day and inter-day precision were all less than 10%, and accuracy of intra-day and inter-day were in the range of −12.7% to 7.9% and −13.9 to 11.8%, respectively. The extraction recoveries of most analytes were more than 60%. The UA-LDS-DLLME/GC–MS method was demonstrated with acceptable precision, accuracy and good specificity for the simultaneous determination of 12 antidepressants and 2 antipsychotics, and has been successfully applied in a real case. [ABSTRACT FROM AUTHOR]

Magnetic mesoporous carbon composites incorporating hydrophilic metallic nanoparticles were synthesized from resol, ZrO(NO), ferric acetylacetonate, and triblock copolymer F127. The method involves a multi-component co-assembly strategy associated with direct carbonization. The resulting carbon material is shown to be useful as a metal oxide affinity chromatography (MOAC) material for enrichment of phosphopeptides owing to its large mesoporous (4.8 nm) surface area (442 m g), large pore volume (0.37 cm g) and excellent hydrophilicity. The metallic iron and ferric oxide particles modified on the mesoporous carbon exert a magnetic force and, in combination with the metallic zirconia, is a viable MOAC material for enrichment of low-abundance phosphopeptides. Because of metal chelation between metallic nanoparticles and the phosphate groups of phosphopeptides, the zirconia/magnetic mesoporous carbon displays high selectivity even at a phosphopeptide/nonphosphopeptide molar ratio of 1:500. As little as 1.5 fmol of phosphopeptides become detectable. The MOAC was successfully applied to the identification by MALDI-TOF MS of phosphopeptides in human serum and nonfat milk. [ABSTRACT FROM AUTHOR]

Sulfite and sulfide share several similarities in terms of chemical properties, such as nucleophilic and reducing reactivities. Therefore, they may disturb the detection of each other. In order to discriminate between these two kinds of sulfur-containing species, a new probe TSSP-N3 was developed, in which para-azidobenzenyl ketone was covalently incorporated to a coumarin fluorophore linked by a C=C double bond. Sulfite and sulfide can respectively react with the C=C double bond and the azido group to give different products, consequently, they can be differentially identified by UV-vis and fluorescence spectroscopy as well as by the naked eye. Selectivity and competition results reveal that TSSP-N3 is a good candidate for the detection of sulfide and sulfite. The bioimaging experiment demonstrates the potential of the TSSP-N3 probe for the differential imaging of sulfide and sulfite in living cells. [ABSTRACT FROM AUTHOR]

This study was designed to develop a sensitive and reliable RP-HPLC method for the separation of aerial parts ofJologbo. Different extraction methods were used and compared to obtain the maximum number of constituents. Different chromatographic conditions were optimized to achieve optimum separation. A total of 98 peaks were obtained in the optimized separation method. Seasonal variation and difference in chemical composition among aerial parts of the plant were evaluated. Significant difference in the chemical composition was observed and statistical data processing supported the results. The correlation coefficient and vector cosine were calculated by chemometric analysis to evaluate peak retention times, peak areas, and peak heights between various batches (using selected peaks) which showed good repeatability. Gallic and protocatechuic acids were identified from the plant and their intra-day and inter-day repeatability values were calculated and convincing results were obtained. [ABSTRACT FROM AUTHOR]