A tunable light-mixing liquid crystal lens-like cell (LCLC) is proposed to limit color shift and improve the viewing angle performance. The LCLC is attached on a collimated display, which is ...introduced to avoid the blue shift of OLED or phase difference of LCD. At voltage on-state, the incident light with low color shift is mixed by the LCLC to ensure the low color shift at different viewing angles, the brightness is also diffused to large viewing angles. At voltage off-state, the incident light is invariant after it is transmitted the LCLC. Using LCLC, display can meet more complex requirement owing to the tunable property of brightness distribution.
Catalytic hydrogenation or transfer hydrogenation of quinolines was thought to be a direct strategy to access dihydroquinolines. However, the challenge is to control the chemoselectivity and ...regioselectivity. Here we report an efficient partial transfer hydrogenation system operated by a cobalt-amido cooperative catalyst, which converts quinolines to 1,2-dihydroquinolines by the reaction with H
N·BH
at room temperature. This methodology enables the large scale synthesis of many 1,2-dihydroquinolines with a broad range of functional groups. Mechanistic studies demonstrate that the reduction of quinoline is controlled precisely by cobalt-amido cooperation to operate dihydrogen transfer from H
N·BH
to the N=C bond of the substrates.
In situ growing transition metals on N‐doped carbon by atomic doping produces a class of promising alternatives to replace Pt‐based catalysts for redox reactions, yet still suffer from unsatisfactory ...activity and durability in acidic and basic media. Herein, a simple synthetic strategy to fabricate an MnO modifying Co‐Nx/C catalyst with high activity and robust durability is presented. The interphase engineering well controls the Co and N species in the carbon matrix, affording the material with more pyridine N and graphite N; the interaction between Co‐Nx and MnO phase is also well discussed. Accordingly, the obtained Co‐Nx/C‐MnO catalyst exhibits excellent electrocatalytic properties towards oxygen reduction reaction, achieving a half‐wave potential of 0.87 and 0.66 V versus reversible hydrogen electrode in 0.1 m KOH and 0.1 m HClO4 solutions, as well as excellent durability with only −16.9 and −12.2 mV shift after 1000 cycles, respectively. This study provides insights into the design of noble‐metal‐free electrocatalysts from the perspective of active sites and catalyst carriers.
A simple two‐step solid‐phase method is illustrated to obtain the Co‐Nx/C‐MnO catalyst rich of active Co‐Nx moieties. It is unravelled that the Co dopant tunes the intrinsic valence state of Mn meanwhile the synergistic Mn‐Co‐Nx center attenuates the affinity of adsorbed species, thus facilitating oxygen reduction reaction (ORR) kinetics. Particularly, the acidic ORR stability of this catalyst is greatly enhanced by promoting the dissociation of intermediate OOH* and suppressing the H2O2 generation. This study provides a new idea for the design of high active and durable ORR catalysts for clean energy conversion.
Every year cervical cancer affects more than 300,000 people, and on average one woman is diagnosed with cervical cancer every minute. Early diagnosis and classification of cervical lesions greatly ...boosts up the chance of successful treatments of patients, and automated diagnosis and classification of cervical lesions from Papanicolaou (Pap) smear images have become highly demanded. To the authors' best knowledge, this is the first study of fully automated cervical lesions analysis on whole slide images (WSIs) of conventional Pap smear samples. The presented deep learning-based cervical lesions diagnosis system is demonstrated to be able to detect high grade squamous intraepithelial lesions (HSILs) or higher (squamous cell carcinoma; SQCC), which usually immediately indicate patients must be referred to colposcopy, but also to rapidly process WSIs in seconds for practical clinical usage. We evaluate this framework at scale on a dataset of 143 whole slide images, and the proposed method achieves a high precision 0.93, recall 0.90, F-measure 0.88, and Jaccard index 0.84, showing that the proposed system is capable of segmenting HSILs or higher (SQCC) with high precision and reaches sensitivity comparable to the referenced standard produced by pathologists. Based on Fisher's Least Significant Difference (LSD) test (P < 0.0001), the proposed method performs significantly better than the two state-of-the-art benchmark methods (U-Net and SegNet) in precision, F-Measure, Jaccard index. For the run time analysis, the proposed method takes only 210 seconds to process a WSI and is 20 times faster than U-Net and 19 times faster than SegNet, respectively. In summary, the proposed method is demonstrated to be able to both detect HSILs or higher (SQCC), which indicate patients for further treatments, including colposcopy and surgery to remove the lesion, and rapidly processing WSIs in seconds for practical clinical usages.
Summary
The effect of non‐thermal treatment on the solubility and structural properties of rice bran protein was investigated. It was shown that the non‐thermal treatment significantly improved the ...solubility of rice bran protein, in which, HHP and US increased it by 76.69% and 136.75%, respectively. The structural analysis showed that the non‐thermal treatment reduced the β‐sheet content and increased the content of free sulfhydryl groups on the surface, indicating that the inter‐chain hydrogen and disulfide bonds of rice bran protein were broken and the protein structure shifted from order to disorder. And the internal chromogenic groups of the protein were exposed and tended to the hydrophilic environment, indicating the exposure of hydrophilic groups. This study provides a theoretical basis for non‐thermal modification of rice bran protein and its processing and utilisation.
Effect of HHP and US treatment on solubility and structure of rice bran protein.
Genetic correlations between quantitative traits measured in many breeding programs are pervasive. These correlations indicate that measurements of one trait carry information on other traits. ...Current single-trait (univariate) genomic selection does not take advantage of this information. Multivariate genomic selection on multiple traits could accomplish this but has been little explored and tested in practical breeding programs. In this study, three multivariate linear models (i.e., GBLUP, BayesA, and BayesCπ) were presented and compared to univariate models using simulated and real quantitative traits controlled by different genetic architectures. We also extended BayesA with fixed hyperparameters to a full hierarchical model that estimated hyperparameters and BayesCπ to impute missing phenotypes. We found that optimal marker-effect variance priors depended on the genetic architecture of the trait so that estimating them was beneficial. We showed that the prediction accuracy for a low-heritability trait could be significantly increased by multivariate genomic selection when a correlated high-heritability trait was available. Further, multiple-trait genomic selection had higher prediction accuracy than single-trait genomic selection when phenotypes are not available on all individuals and traits. Additional factors affecting the performance of multiple-trait genomic selection were explored.
In this work, we have developed an electrochemical aptasensor for high-sensitivity determination of carcinoembryonic antigen (CEA) based on lead ion (Pb2+)-dependent DNAzyme-assisted signal ...amplification and graphene quantum dot-ionic liquid-nafion (GQDs-IL-NF) composite film. We designed hairpin DNA containing CEA-specific aptamers and DNAzyme chains. In the presence of CEA, hairpin DNA recognized the target and performed a DNAzyme-assisted signal amplification reaction to yield a large number of single-stranded DNA. The GQDs-IL-NF composite film was immobilized on the glassy carbon electrode for the interaction with single-stranded DNA through noncovalent π-π stacking interaction. Therefore, the methylene blue-labeled substrate DNA (MB-substrate) was fixed on the electrode and exhibited an initial electrochemical signal. Under optimal conditions, the response current change was proportional to the concentration of CEA, demonstrating a wide linear range from 0.5fgmL−1 to 0.5ngmL−1, with a low detection limit of 0.34fgmL−1. Furthermore, the proposed aptasensor was successfully applied in determining CEA in serum samples, showing its superior prospects in clinical diagnosis.
•Pb2+dependent DNAzyme electrochemical biosensor for carcinoembryonic antigen detection was developed.•The graphene quantum dots-ionic liquid-nafion composite film was fabricated on electrode for the first time.•The target-aptamer complex recycling led to continuous cleavage of substrate chain and amplified electrochemical signal.•The method has been applied in human serum, with high selectivity and good recovery.
Abstract In the probabilistic seismic performance assessment of structures, intensity measures (IMs) represent seismic characteristics and variations. Traditional fragility analysis method based on ...the assumption of linear regression requires selecting an optimal IM as input variable. By introducing machine learning (ML) techniques, nonparametric fragility analysis theoretically allows for considering all potential IMs as inputs. Nevertheless, to reduce input dimensionality and improve training efficiency, the feature selection of IMs remains imperative. This paper proposes a method to select optimal ground motion IMs for data‐driven surrogate modeling of structures. Specifically, the elastic net algorithm is employed to select the optimal multiple IMs based on the coefficient of determination and regression coefficient, differing from the efficiency and practicality emphasized in the traditional method. Using the optimal multiple IMs as input variables, several ML techniques are employed to construct surrogate models for seismic damage assessment of structures, thereby developing fragility functions, that is, the conditional probability of exceeding a damaged state given seismic intensity. A 3‐span, 6‐storey, reinforced concrete frame is utilized to illustrate the proposed methodology. The predictive performance of all ML models with the optimal multiple IMs outperforms that of the models with the commonly used IM (e.g., peak ground acceleration, PGA ) as sole input and all candidate IMs as inputs. Additionally, the surrogate models with the optimal multiple IMs enable a more comprehensive seismic fragility modeling of structures under two or more IMs simultaneously, such as the fragility surface under spectral acceleration at 1.0s ( Sa ‐1.0s) and velocity spectrum intensity ( VSI ).
Developing universal stimuli‐responsive materials capable of emitting a broad spectrum of colors is highly desirable. Herein, we deliberately grafted a conformation‐adaptable organic chromophore into ...the established coordination space of a flexible metal–organic framework (MOF). In terms of the coupled structural transformations and the space confinement, the chromophore in the MOF matrix underwent well‐regulated conformational changes under physical and chemical stimuli, simultaneously displaying thermo‐, piezo‐, and solvato‐fluoro‐chromism with color tunability over the visible range. Owing to the resilient nature and the reduced dimensionality of the selected coordination space, all three color modulations behaved in a sensitive and self‐reversible manner, each following a linear correlation of the emission maximum with stimulus. Single‐crystal X‐ray diffraction of the variable‐temperature structures and solvent‐inclusion crystals elucidated the intricate color varying mechanisms.
A smart luminescent material was constructed by anchoring an organic chromophore into the 2D coordination space of a flexible metal–organic framework. Thermo‐, piezo‐, and solvato‐fluoro‐chromisms were simultaneously achieved within a single material, featuring dynamic full‐color tunability, excellent reversibility, and linear sensor response.
Colloidal all‐inorganic perovskites nanocrystals (NCs) have emerged as a promising material for display and lighting due to their excellent optical properties. However, blue emissive NCs usually ...suffer from low photoluminescence quantum yields (PLQYs) and poor stability, rendering them the bottleneck for full‐color all‐perovskite optoelectronic applications. Herein, a facile approach is reported to enhance the emission efficiency and stability of blue emissive perovskite nano‐structures via surface passivation with potassium bromide. By adding potassium oleate and excess PbBr2 to the perovskite precursor solutions, potassium bromide‐passivated (KBr‐passivated) blue‐emitting (≈450 nm) CsPbBr3 nanoplatelets (NPLs) is successfully synthesized with a respectably high PLQY of 87%. In sharp contrast to most reported perovskite NPLs, no shifting in emission wavelength is observed in these passivated NPLs even after prolonged exposures to intense irradiations and elevated temperature, clearly revealing their excellent photo‐ and thermal‐stabilities. The enhancements are attributed to the formation of K‐Br bonding on the surface which suppresses ion migration and formation of Br‐vacancies, thus improving both the PL emission and stability of CsPbBr3 NPLs. Furthermore, all‐perovskite white light‐emitting diodes (WLEDs) are successfully constructed, suggesting that the proposed KBr‐passivated strategy can promote the development of the perovskite family for a wider range of optoelectronic applications.
High‐quality blue‐emitting CsPbBr3 nanoplatelets (NPLs) are synthesized via a facile potassium bromide‐enriched surface passivation. The resultant blue‐emitting (≈450 nm) CsPbBr3 NPLs show a high PLQY of 87% with excellent thermal stability and photostability. Furthermore, white light LEDs based on the mixture perovskite materials including the blue‐emitting NPLs are constructed, demonstrating a wide color gamut.
PDF
