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Facile fabrication of copper nanoclusters (CuNCs) with excellent fluorescence is desirable, but remains challenging and scarce for sensing applications in food. In this work, albumin egg (AE) stabilized CuNCs were prepared by a self-assembly templated method. The obtained fluorescent AE-CuNCs exhibited a strong emission at 412 nm upon excitation at 325 nm. Based on the absorption competition quenching mechanism, the AE-CuNCs fluorescent probe for Fe3+ was developed. The probe had good linearity (0.10–1000 µM) with R2 (0.986), low limits of detection (30 nM) and good selectivity. Furthermore, the iron content in noodles, biscuits, light soy sauce and bean sprouts was successfully determined by the fluorescent probe. Highlights: AE-CuNCs with excellent fluorescence were prepared by a templated method. The AE-CuNCs probe had good sensitivity and selectivity for Fe3+ duo to absorption competition quenching mechanism. The proposed AE-CuNCs probe was successfully applied to determine iron content from complex food samples. [ABSTRACT FROM AUTHOR]

The representation learning is the key to deep learning. As a special deep learning algorithm, the generalization performance of the multilayer extreme learning machine (ML-ELM) is influenced by the feature extraction capability of the extreme learning machine autoencoder (ELM-AE). But the ELM-AE does not consider class labels, and it is difficult for the ELM-AE to build the discriminative feature space in the classification tasks. Thus, to improve the class separability of abstract feature, the discriminant regularization is introduced into the ELM-AE and a new regularized ELM-AE called discriminative extreme learning machine autoencoder (DELM-AE) is proposed. And by stacking the ELM-AE for feature extraction and adopting the ELM for classifying, the multilayer discriminative extreme learning machine (ML-DELM) is proposed for classification tasks. The DELM-AE adds the discriminant regularization term to the loss function to reduce the distance between samples and their class centers in feature space. Compared with the ELM-AE and ML-ELM, the DELM-AE and ML-DELM indirectly utilizes the category information contained in the discriminant regularization term to guide the feature extraction. Empirical evaluations and experiments on various benchmark datasets show that feature representation learned by the DELM-AE is discriminative and sparse, and the generalization performance and structural sparsity of ML-DELM are comparable with the other state-of-the-art ML-ELM algorithms. [ABSTRACT FROM AUTHOR]

Pteris cretica L. var. nervosa is one of the most well-known Chinese medicines. Although it is widely used to treat jaundice hepatitis, the main ingredient for its treatment was not thoroughly explored until recently. Essentially, the purpose of this study is to find the monomer compound in Pteris cretica L. var. nervosa, which is most likely to be effective in treating liver injury. Through the model of LPS/D-gal-induced liver injury in mice, the best therapeutic site of the total extract was explored, the chemical components of the parts with the best therapeutic effect were separated, a total of 10 flavonoids were isolated, and the RAW264.7 cells induced by LPS were used as the experimental model to explore the preliminary anti-inflammatory activity of NO production in vitro. Finally, the anti-inflammatory activity and the highest content in this plant Luteolin-7-O-rutinoside (LUT) were selected, as the object of study in vivo. It was found that LUT could not only reduce alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, but also significantly reduce the release of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β), and inhibit PI3K/AKT/AMPK/NF-κB pathway. In addition, LUT can increase levels of SOD and GSH to reduce oxidative stress. It has an obvious therapeutic effect on acute liver injury induced by LPS/D-gal in mice. Therefore, infer LUT is a functional substance in Pteris cretica L. var. nervosa. [ABSTRACT FROM AUTHOR]

Microtubules play a crucial role during the establishment and maintenance of cell polarity. In fission yeast cells, the microtubule plus-end tracking proteins (+TIPs) (including the CLIP-170 homologue Tip1) regulate microtubule dynamics and also transport polarity factors to the cell cortex. Here, we show that the E3 ubiquitin ligase Dma1 plays an unexpected role in controlling polarized growth through ubiquitinating Tip1. Dma1 colocalizes with Tip1 to cortical sites at cell ends, and is required for ubiquitination of Tip1. Although the absence of dma1+ does not cause apparent polar growth defects in vegetatively growing cells, Dma1-mediated Tip1 ubiquitination is required to restrain polar growth upon DNA replication stress. This mechanism is distinct from the previously recognized calcineurin-dependent inhibition of polarized growth. In this work, we establish a link between Dma1-mediated Tip1 ubiquitination and DNA replication or DNA damage checkpoint-dependent inhibition of polarized growth in fission yeast. The microtubule plus-end tracking protein Tip1 regulates microtubule dynamics and polar growth in fission yeast. Here the authors link the ubiquitination of Tip1 by ubiquitin ligase Dma1 to polarized growth inhibition upon DNA replication stress. [ABSTRACT FROM AUTHOR]

Covalent organic framework (COF)–decorated magnetic nanoparticles (Fe3O4@DhaTab) with core–shell structure have been synthesized by one-pot method. The prepared Fe3O4@DhaTab was well characterized, and parameters of magnetic solid-phase extraction (MSPE) for parabens were also investigated in detail. Under optimized conditions, the adsorbent dosage was only 3 mg and extraction time was 10 min. The developed Fe3O4@DhaTab-based MSPE-HPLC analysis method offered good linearity (0.01–20 μg mL−1) with R2 (0.999) and low limits of detection (3.3–6.5 μg L−1) using UV detector at 254 nm. The proposed method was applied to determine four parabens in environmental water samples with recoveries in the range 64.0–105% and relative standard deviations of 0.16–7.8%. The adsorption mechanism was explored and indicated that porous DhaTab shell provided π-π, hydrophobic, and hydrogen bonding interactions in the MSPE process. The results revealed the potential of magnetic-functionalized COFs in determination of environmental contaminants. [ABSTRACT FROM AUTHOR]

Auto-encoders are unsupervised deep learning models, which try to learn hidden representations to reconstruct the inputs. While the learned representations are suitable for applications related to unsupervised reconstruction, they may not be optimal for classification. In this paper, we propose a supervised auto-encoder (SupAE) with an addition classification layer on the representation layer to jointly predict targets and reconstruct inputs, so it can learn discriminative features specifically for classification tasks. We stack several SupAE and apply a greedy layer-by-layer training approach to learn the stacked supervised auto-encoder (SSupAE). Then an adaptive weighted majority voting algorithm is proposed to fuse the prediction results of SupAE and the SSupAE, because each individual SupAE and the final SSupAE can both get the posterior probability information of samples belong to each class, we introduce Shannon entropy to measure the classification ability for different samples based on the posterior probability information, and assign high weight to sample with low entropy, thus more reasonable weights are assigned to different samples adaptively. Finally, we fuse the different results of classification layer with the proposed adaptive weighted majority voting algorithm to get the final recognition results. Experimental results on several classification datasets show that our model can learn discriminative features and improve the classification performance significantly. [ABSTRACT FROM AUTHOR]

The intuitionistic fuzzy set (IFS), as a generation of Zadeh's fuzzy set, can express and process uncertainty much better. Similarity measures between IFSs are used to indicate the similarity degree between the information carried by IFSs. Although several similarity measures for IFSs have been proposed in previous studies, some of them cannot satisfy the axioms of similarity, or provide counterintuitive cases. In this paper, we first review several widely used similarity measures and then propose a new similarity measures. As the consistency of two IFSs, the proposed similarity measure is defined based on the direct operation on the membership function, non-membership function, hesitation function and the upper bound of membership function of two IFS, rather than based on the distance measure or the relationship of membership and non-membership functions. It proves that the proposed similarity measure satisfies the properties of the axiomatic definition for similarity measures. Comparison between the previous similarity measures and the proposed similarity measure indicates that the proposed similarity measure does not provide any counterintuitive cases. Moreover, it is demonstrated that the proposed similarity measure is capable of discriminating difference between patterns. Experiments on medical diagnosis and cluster analysis are carried out to illustrate the applicability of the proposed similarity measure in practice. [ABSTRACT FROM AUTHOR]

Single-molecule magnets (SMMs) are regarded as promising candidates for ultrahigh-density storage, quantum information processing and molecular spintronics. It is a crucial challenge for chemists to modulate magnetic dynamics of SMMs. Here, we successfully synthesized two 3d-4f polynuclear compounds [Co2Dy(TTTTCl)2(MeOH)]NO3·3MeOH (1) and [Co2Dy(TTTTCl)2 (MeOH)][Co(HTTTTCl)](NO3)2·2.5MeOH·2H2O (2), where H3TTTTCl=2,2′,2′′-(((nitrilotris(ethane-2,1-diyl)) tris(azanediyl)) tris(methylene))tris-(4-chlorophenol). On applying the approach by co-crystallization of bulky diamagnetic moiety, the effective energy barrier enhances from 401 K (1) to 536 K (2), which are both among the highest d-f heterometallic SMMs. [ABSTRACT FROM AUTHOR]

Hard-inert materials such as diamond, silicon carbide, gallium nitride, and sapphire are difficult to obtain from the smooth and damage-free surfaces efficiently required by semiconductor field. Therefore, this study proposed a chemical kinetics model to evaluate the material removal rate of diamond in chemical mechanical polishing process and to investigate the material removal mechanism by examining the surface information with optical microscopy, surface profilometry, and atomic force microscopy as well as X-ray photoelectron spectroscopy. The theoretical and experimental results show that chemical and mechanical synergic effect may promote the diamond oxidation reaction in chemical kinetics. The material removal rate is acceptable when the mechanical activation coefficient is smaller than 0.48. The 2.5 μm B4C abrasives, the polishing temperature of 50 °C, and the polishing pressure of 266.7 MPa are optimal parameters for diamond polishing with potassium ferrate slurry. It provides the highest material removal rate of 0.055 mg/h, the best surface finish (about Ra 0.5 nm) and surface quality (no surface scratches or pits). It then discusses how mechanical stress may promote the chemical oxidation of oxidant and diamond by forming "C-O," "C=O," and "O=C-OH" on diamond surface. The study concludes that chemical kinetics mechanism is effective for the investigation of the synergic effect in chemical mechanical polishing hard-inert materials. [ABSTRACT FROM AUTHOR]

This paper addresses the combination of unreliable evidence sources which provide uncertain information in the form of basic probability assignment (BPA) functions. We proposed a novel evidence combination rule based on credibility and non-specificity of belief functions. Following a review of all existing non-specificity measures in evidence theory, a non-specificity measure for evidence theory is discussed. It is claimed that the non-specificity degree of a BPA is related to its ability of pointing to one and only one element. Based on the difference between the largest belief grades and other belief grades, a non-specificity measure is defined. Properties of the proposed non-specificity measure are put forward and proved mathematically. Illustrative examples are employed to show the properties of non-specificity measure. After providing a procedure for the evaluation of evidence credibility, we propose a novel evidence combination rule. Numerical example and application in target identification are applied to demonstrate the performance of our proposed evidence combination rule. [ABSTRACT FROM AUTHOR]

Uncertainty measure can supply a new viewpoint for analyzing knowledge conveyed by an Atanassov's intuitionistic fuzzy set (AIFS). So uncertainty measurement is a key topic in AIFS theory, analogous to the role of entropy in probability theory. After reviewing the existing measures of uncertainty (entropy) for AIFSs, we argue that the existing measures of uncertainty cannot capture all facets of uncertainty associated with an AIFS. Then we point out and justify that there are at least three kinds of uncertainty for an AIFS, namely non-specificity, fuzziness, and intuitionism. We provide formal measures of non-specificity, fuzziness, and intuitionism, together with their properties and proofs. Properties of the proposed non-specificity measure are especially investigated. Finally, a general uncertainty measure consisting of these three uncertainties is presented. Illustrative examples show that the proposed uncertainty measure is consistent with intuitive cognize, and it is more sensitive to changes of AIFSs. Moreover, the proposed uncertainty measure can also discriminate uncertainty hiding in classical sets. Thus, it provides an alternative way to construct unified uncertainty measures. [ABSTRACT FROM AUTHOR]

A high-order Lagrangian cell-centered conservative gas dynamics scheme is presented on unstructured meshes. A high-order piecewise pressure of the cell is introduced. With the high-order piecewise pressure of the cell, the high-order spatial discretization fluxes are constructed. The time discretization of the spatial fluxes is performed by means of the Taylor expansions of the spatial discretization fluxes. The vertex velocities are evaluated in a consistent manner due to an original solver located at the nodes by means of momentum conservation. Many numerical tests are presented to demonstrate the robustness and the accuracy of the scheme. [ABSTRACT FROM AUTHOR]

This paper presents a Lagrangian cell-centered conservative gas dynamics scheme. The piecewise constant pressures of cells arising from the current time sub-cell densities and the current time isentropic speed of sound are introduced. Multipling the initial cell density by the initial sub-cell volumes obtains the sub-cell Lagrangian masses, and dividing the masses by the current time sub-cell volumes gets the current time subcell densities. By the current time piecewise constant pressures of cells, a scheme that conserves the momentum and total energy is constructed. The vertex velocities and the numerical fluxes through the cell interfaces are computed in a consistent manner due to an original solver located at the nodes. The numerical tests are presented, which are representative for compressible flows and demonstrate the robustness and accuracy of the Lagrangian cell-centered conservative scheme. [ABSTRACT FROM AUTHOR]

Compared are two approaches for the biotinylation of poly( N-isopropylacrylamide- co-vinylacetic acid) microgels, 300-nm diameter, water swollen particles with a corona of carboxyl groups. The biotinylated microgels are a platform for bioactive water-based ink. Streptavidin binding was measured as a function of biotin density, and the results were interpreted with a new model that predicts the minimum local density of biotins required to capture a streptavidin. An amino-polyethylene glycol derivative of biotin gave higher biotin contents than a biotin hydrazide. However, the streptavidin content versus biotin content results for both biotin derivatives fell on the same master curve with maximum biotin coverage of 0.11 mg of bound streptavidin per milligram of biotinylated microgel. Exclusion experiments showed that streptavidin was too big to penetrate the cross-linked microgel structure; thus, the conjugated streptavidin was restricted to the microgel surface. The colloidal stability of the microgels was preserved, and the biotinylated products showed good hydrolytic stability. [ABSTRACT FROM AUTHOR]

A monosomic addition line of Aegilops tauschii chromosome 1D in Triticum durum cv. PBW114 was produced in 1990. This line was self-pollinated and maintained for several generations while following the presence of chromosome 1D carrying the gene for red glume color. Cytological analysis indicated that two of the three derivative lines had substitution of chromosome 1D for 1A and another had substitution of chromosome 1D for 1B. One of these lines carried a pair of small chromosomes in addition to the 1D chromosome. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of the derived lines showed the presence of high-molecular-weight (HMW) glutenin encoded by the Glu-D1 locus. The small chromosome found in one of the lines had nearly regular pairing and transmission to daughter nuclei. Fluorescent in situ hybridization (FISH) and analysis of molecular markers indicated that the small chromosome was derived from the short arm of chromosome 1A and carried the Glu-A3 locus. Microsatellite mapping based on the deletion bin map revealed that the small chromosome had terminal deletions on both the terminal and centromeric sides. The line with the small chromosome showed improvement of the sodium dodecyl sulfate (SDS)-sedimentation value as compared to parent durum. However, the increase in SDS-sedimentation value was more significant in the substitution line of chromosome 1D for 1A without the small chromosome. These facts suggest a negative effect of the Glu-A3 locus on dough strength. The sequence of the Glu-D1 locus from these lines showed that the HMW glutenin subunits were Ae. tauschii specific 2t + T2, which were previously found to be associated with poor rheological properties and bread loaf volume in synthetic hexaploid wheat by other workers. Thus, the significant improvement in the SDS-sedimentation value of the substitution line of 1D for 1A suggests that the absence of the negative effect of chromosome 1A on quality is more important than the presence of Glu-D1 of Ae. tauschii. [ABSTRACT FROM AUTHOR]

Abstract  Genomic constitutions of three taxa of Hystrix Moench, H. patula, H. duthiei ssp. duthiei and H. duthiei ssp. longearistata, were examined by meiotic pairing behavior and genomic in-situ hybridization. Meiotic pairing in hybrids of H. patula × Pseudoroegneria spicata (St), H. patula × Elymus wawawaiensis (StH), H. patula × H. duthiei ssp. longearistata, H. patula × Psathyrostachys huashanica (Ns h ), H. duthiei ssp. duthiei × Psa. huashanica, H. duthiei ssp. longearistata × Psa. huashanica, Leymus multicaulis (NsXm) × H. duthiei ssp. longearistata averaged 6.53, 12.83, 1.32, 0.29, 5.18, 5.11 and 10.47 bivalents per cell, respectively. The results indicate that H. patula has the StH genome and H. duthiei ssp. duthiei and H. duthiei ssp. longearistata have the NsXm genome. Results of genomic in-situ hybridization analysis strongly supported the chromosome pairing data; therefore it is concluded that the type species of Hystrix, H. patula, should be included in Elymus, and that H. duthiei ssp. duthiei and H. duthiei ssp. longearistata should be transferred to Leymus. [ABSTRACT FROM AUTHOR]

We study the effects of outsiders' threat and consecutive offers in the two-person bargaining model of Shaked and Sutton (1984). In our first model, there are no outsiders and the firm can make two consecutive offers for every given number of periods. Our first model has the same unique equilibrium as in Shaked and Sutton (1984). In our second model, the firm can switch between rival partners but cannot change the alternating proposing sequence. Our second model has the same perfect equilibrium as in Rubinstein (1982). So the key factor that leads to the equilibrium of Shaked and Sutton (1984) is the possibility of firm's consecutive offers, not the outsiders' threat. [ABSTRACT FROM AUTHOR]

The excitability of individual dendritic branches is a plastic property of neurons. We found that experience in an enriched environment increased propagation of dendritic Na+ spikes in a subset of individual dendritic branches in rat hippocampal CA1 pyramidal neurons and that this effect was mainly mediated by localized downregulation of A-type K+ channel function. Thus, dendritic plasticity might be used to store recent experience in individual branches of the dendritic arbor. [ABSTRACT FROM AUTHOR]