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Outlier detection methods based on distance measure have been used in numerous applications due to their effectiveness and interpretability. However, distances among instances heavily depend on the feature space in which they reside. For an outlier, distances from it to the normal instances may be extremely close in one feature space, failing to separate them from each other, while this situation is reversed in another space. Meanwhile, the distance measure is sensitive to a few “marginal instances” (i.e., normal instances located very close to outliers in the feature space) during the estimation of whether a test instance is an outlier or not. In this article, we propose a robust multi-kernel nearest neighborhood (RMKN) method for outlier detection. Specifically, in the training phase, we only consider normal instances and transform them into a Polynomial kernel function weighted digraph to capture their geometric relationships in the original feature space. Then, we develop an objective function based on the weighted digraph to find a latent feature space via multi-kernel learning such that distances among normal instances in this latent feature space are as close as possible while preserving their original distributions. In the detecting phase, we design an outlying score based on the two-stage multi-kernel $k$k-nearest nearest neighbors to detect outliers. Extensive experiments with ten datasets show that RMKN is effective and robust.

Quaternary ammonium compounds (QACs) become emerging pollutants and their toxicities earn increasing attention. So far, their reproductive toxicities were poorly investigated, and their effects over generations were even less explored. In the present study, reproductive toxicities of two QACs, i.e., tetradecyltrimethylammonium chloride (TTAC) and tetradecyltrimethylammonium bromide (TTAB) were studied on Caenorhabditis eleganswith a consecutive exposure over four generations (from F1 to F4). The effects of TTAC on total and initial reproduction showed stimulation and inhibition, which oscillated from F1 to F4. The effects of TTAB on the total reproduction commonly showed stimulation over generations with the greatest stimulation in F2, and it inhibited the initial reproduction but stimulated the reproduction duration. Further exploration demonstrated that TTAC and TTAB significantly disturbed the levels of spermatocyte protein 8 (SPE8), sperm transmembrane protein 9 (SPE9), vitellogenin (Vg), major sperm protein (MSP) and ephrin receptor protein tyrosine kinase (VAB-1) and the expressions of vab-1, ceh-18, set-2, met-2and mes-4. Such disturbances demonstrated that both QACs impacted the reproductive processes viaoocyte meiosis, gonadal support and germline development. Notably, the effects of TTAC and TTAB in parents were connected with those in the offspring, which highlighted the roles of reproduction in connecting generations. In addition, different effects between TTAC and TTAB demonstrated the anionic influences on the QACs’ toxicities.

Antibiotics are emerging pollutants with pseudo-persistence. However, their reproductive toxicities over generations and underlying mechanisms were seldom explored. In the present study, reproductive effects of erythromycin(ERY) and sulfamethoxazole(SMZ) were studied on Caenorhabditis elegans(C. elegans) with multi-generational exposure from F1 to F4, and their effects in the non-direct exposed offspring of F1 and F4(T4 and T4’) were explored to investigate trans-generational outcomes. At high concentrations, ERY and SMZ inhibited the reproduction and the inhibition decreased with more generations’ exposure. At low concentrations, SMZ stimulated reproduction in T4, opposite to its inhibition in F1. Further analysis on ten enzymes and proteins in lipid and glucolipid metabolism showed that ERY commonly inhibited fatty acid synthetase(FAS) in F1 to F4, while ERY and SMZ showed stimulation and inhibition on other biochemicals. Integrated biomarker response(IBR) index values showed that ERY and SMZ stimulated the overall metabolism in F1, and the stimulation decreased and even altered to inhibition in later generations. When comparing multi- and trans-generational effects, ERY and SMZ at high concentration caused inhibition on reproduction in T4 and stimulation in T4’, which were opposite to those in F1 and F4.

Guided waves can propagate from flat plates to curved structures and carry structural health information. In this paper, an ultrasonic guided wave inspection method is proposed for detecting damages in curved parts made of carbon fibre reinforced plastics (CFRPs), such as hat-stringer-stiffened panel. By collecting full wavefield information, we obtain the standing wave information formed by the interaction between guided waves and damage. The interaction mechanism between guided waves and damage is simulated through finite element simulation, and the wavefield curvature imaging algorithm is used to generate a damage image in the curved area. Furthermore, a specimen with delamination damages is fabricated, and full wavefield information is collected through a scanning laser Doppler vibrometer (SLDV). We then use the proposed imaging algorithm to detect delamination damages of different sizes. The experimental results were consistent with the simulation results, confirming the effectiveness of the proposed method. Notably, the technology combines the advantages of guided waves and SLDV, which can obtain full wavefield information without contact, including damage-related characteristics. This work provides a convenient and comprehensive method for collecting wavefield information on complex curved CFRP parts for structural health monitoring, which would significantly improve quality control for CFRP components in various fields.

Vanadium (V)-based oxides with a high theoretical capacity are an alternative anode for lithium-ion (Li+) batteries, but they are still limited by the poor conductivity, large volume change and low active material mass loading. Herein, a three-dimensional (3D) continuous C/CuVO3@Cu composite anode with high copper (II) metavanadate (IV) (CuVO3) mass loading is synthesized by the combination of high-energy ball milling, non-solvent-induced phase separation and heat treatment. The copper (Cu) framework can enhance electron/ion conductivity in coordination with amorphous carbon (C). Furthermore, the macropore channels in the copper framework can provide buffer space for the volume expansion of active material copper (II) metavanadate (IV) during lithiation/delithiation. As a result, this 3D continuous C/CuVO3@Cu composite anode achieves a high copper (II) metavanadate (IV) mass loading of about 3.8 mg/cm2, delivering a reversible capacity of 479 mAh/g at 100 mA/g after 120 cycles. More importantly, a long life span is achieved with a reversible capacity of 268 mAh/g even after 1700 cycles at a high current density of 1000 mA/g, demonstrating excellent cycle performance. This work provides a way to develop 3D continuous composite material anodes with extraordinary electrochemistry performance for next-generation energy-storage devices.

An interrupted Pummerer reaction of PhICl2and sulfoxides was found to in situ generate reactive organosulfenyl chloride, which enabled the intramolecular electrophilic cyclization of 2-alkynylanilines, generating 3-sulfenylated indole with a good to excellent yield under metal-free conditions. One striking feature of the approach is that sulfoxide regeneration can be realized via the oxidation of the formed sulfides by the generated hypervalent iodine species.

This report described that a series of 4‐chalcogenylated isoxazoles were readily synthesized from the one‐pot reaction of alkynone Z‐O‐methyloximes with (dichloroiodo)benzene (PhICl2) and diorganyl disulfides/diselenides under metal‐free conditions. The reaction process was enabled by the electrophilic organosulfenyl chloride (RSCl) or selenenyl chloride (RSeCl) species, which were generated in situfrom the reaction of PhICl2and diorganyl disulfides/diselenides. The striking feature of the approach is the in‐situformation of the electrophilic RSCl or RSeCl species, thus markedly decreasing the total usage of electrophiles when compared with the existing methods. This method exhibited a good functional groups tolerance for both alkynone Z‐O‐methyloximes and diorganyl disulfides/diselenides and the reaction could proceed at room temperature under ambient atmosphere within a short time to afford a series of functionalized isoxazoles in moderate to excellent yields. 4‐Chalcogenylated isoxazoles were readily synthesizedfrom the one‐pot reaction of alkynone Z‐O‐methyloximes with PhICl2and diorganyl disulfides/diselenides under metal‐free conditions. This intramolecular cyclization/chalcogenylation process was postulated to be enabled by the electrophilic organosulfenyl chloride (RSCl) or selenenyl chloride (RSeCl) species, generated in situfrom the reaction of PhICl2and diorganyl disulfides/diselenides.

Sodium metal has been widely studied in the field of batteries due to its high theoretical specific capacity (∼1,166 mAh/g), low redox potential (-2.71 V compared to standard hydrogen electrode), and low-cost advantages. However, problems such as unstable solid electrolyte interface (SEI), uncontrolled dendrite growth, and side reactions between solid-liquid interfaces have hindered the practical application of sodium metal anodes (SMAs). Currently, lots of strategies have been developed to achieve stabilized sodium metal anodes. Among these strategies, modified metal current collectors (MCCs) stand out due to their unique role in accommodating volumetric fluctuations with superior structure, lowering the energy barrier for sodium nucleation, and providing guided uniform sodium deposition. In this review, we first introduced three common metal-based current collectors applied to SMAs. Then, we summarized strategies to improve sodium deposition behavior by optimally engineering the surface of MCCs, including surface loading, surface structural design, and surface engineering for functional modification. We have followed the latest research progress and summarized surface optimization cases on different MCCs and their applications in battery systems.

The nitrile group is an important functional group widely found in both pharmaceutical agents and natural products. More than 30 nitrile-containing pharmaceuticals have been approved by the FDA for the management of a broad range of clinical conditions in the last few decades. Incorporation of a nitrile group into lead compounds has gradually become a promising strategy in rational drug design as it can bring additional benefits including enhanced binding affinity to the target, improved pharmacokinetic profile of parent drugs, and reduced drug resistance. This paper reviews the existing drugs with a nitrile moiety that have been approved or in clinical trials, involving their targets, molecular mechanism of pharmacology and SAR studies, and classifies them into different categories based on their clinical usages.

Silicon (Si) possesses high theoretical lithium-ion (Li+)-storage capability but is still limited to a huge volume change in the charging–discharging process and has poor conductivity, which hinders its application. Here, the authors report a novel three-dimensional (3D) continuous porous silicon/copper (Cu) composite film through non-solvent-induced phase separation and heat treatment. The composite film inherits the developed 3D channels of copper with a proper pore size (1–5 μm), while the silicon particles can evenly adhere onto the 3D copper current collector tightly by heat treatment. It provides a reversible capacity of up to 2054.9 mAh/g after 150 cycles under a current of 0.05 C and exhibits a good rate capability (609.9 mAh/g at a high rate of 1 C) when used as an electrode. Naturally, the 3D porous architecture could not only shorten the electron/ion transmission path but also induce space-confined silicon, which provides a stable space for the volume expansion/contraction of silicon to restrict pulverization. This strategy provides ideas for the development of high-energy-density electrodes for next-generation energy-storage systems.

Antibiotics have recently gained attention because they are emerging environmental pollutants with obesogenic properties. In this study, Drosophila melanogasterwere exposed to sulfamethoxazole (SMX), a sulfonamide antibiotic, and the effects were measured on circadian rhythm (represented by the eclosion rhythm), lipid metabolism, and microbiota. Circadian rhythm disorder was considered due to its connection with lipid metabolism and microbiota in association with obesity. SMX decreased the proportion of adult flies that eclosed in the morning (AM adults) and increased the proportion of PM adults. Moreover, SMX increased the body weight of PM adults, indicating that SMX exposure caused dysrhythmia in eclosion together with obesity. In measurements of key metabolites and metabolic enzymes, SMX exposure stimulated 3 indices in AM adults and 10 indices in PM adults. In AMP-activated protein kinase and insulin/IGF-1 signaling pathways, SMX upregulated six genes in AM adults and nine genes in PM adults. Finally, microbiota analysis demonstrated that SMX increased the Firmicutes/Bacteroides ratios (F/B) by 79.6- and 5.8-fold compared to concurrent controls in AM and PM adults. Collectively, these results suggest that SMX showed obesogenic effects accompanied with dysrhythmia and disturbances in lipid metabolism and microbiota. Further studies on the intrinsic connection are needed.

During the past several decades, hypervalent iodine reagents have been widely used in various organic transformations. Specifically, these exclusive classes of reagents have been extensively used for the construction of carbon-carbon bonds. This review aims to cover all the reactions involving the construction of carbon-carbon bonds mediated by hypervalent iodine reagents, providing references and highlights for synthetic chemists who are interested in hypervalent iodine chemistry.

A novel Cu-SnO2anode material derived from Cu6Sn5alloy, retaining high conductivity of Cu and high theoretical capacity of SnO2with a facile synthesizing process by oxidation and reduction method. The novel Cu structure penetrates in the composite particles inducing high conductivity and space-confined SnO2, which restrict the pulverization of SnO2during lithiation/delithiation process.

The decorated copper and oxygen vacancies were simultaneously induced in Cu-Mn bimetallic oxides by phase separation and hydrogen etching, which synergistically promote an efficient sodium ion storage mechanism.

The high theoretical capacity of germanium (Ge) is considerably restricted in practical applications due to the low conductivity and large volume variation range. The complex preparation process will further hinder the development of Ge anodes in lithium-ion batteries. In this paper, the Ge/Cu3Ge/GeO2composites with a continuous channel structure are composed of conductive Cu3Ge and high-capacity GeO2dispersed in a Ge matrix, which were prepared by melt spinning, de-alloying, and oxidation in easy massive production. The optimized sample of D-Cu2Ge8-600 showed excellent cycling performance with a specific capacity of 875.7 mAh g–1after 500 cycles at a current density of 0.1 A g–1. D-Cu2Ge8-600 also presents outstanding electrochemical performance in a full cell composed of commercial LiCoO2. The high lithium storage performance is inextricably attributed to that Cu3Ge and GeO2allow Ge nanoparticles to be uniformly dispersed in a continuous channel structure providing volume space. Among them, the Cu3Ge phase acts as a conductive network. Concurrently, GeO2improves the specific capacity of the whole electrode material. The easily prepared composites on a large scale could provide a novel route for future practical applications of Si- and Ge-based anode materials.

A highly substituent-dependent rearrangement allows for the novel and SOCl2-induced divergent synthesis of 3-methylthioquinolin-2-ones and 3-methylthiospiro[4.5]trienones through intramolecular electrophilic cyclization of N-aryl propyamides. DMSO acts as both solvent and sulfur source, and use of DMSO-h6/d6enables the incorporation of SCH3or SCD3moieties to the 3-position of the heterocyclic framework. Different para-substituents trigger divergent reaction pathways leading to the formation of quinolin-2-ones for mild substituents and spiro[4,5]trienones for both electron-withdrawing and -donating substituents, respectively. On the basis of both computational and experimental results, a new mechanism has been put forward that accounts for the exclusive spirolization/defluorination process and the surprising substituent effects.

A metal-free sulfenylation/spirocyclization of indolyl-ynones realized by organosulfenyl chloride, generated in situfrom the reaction of disulfides and PhICl2, is presented. This cascade one-pot process enables a chemoselective synthesis of diverse sulfenylated spiroindolenines depending on the substituent pattern at the two-position of indolyl-ynones.

Increased understanding of the functions of lactate has suggested a close relationship between lactate homeostasis and normal brain activity because of its importance as an energy source and signaling molecule. Here we show that lactate levels affect adult hippocampal neurogenesis. Cerebrovascular-specific deletion of PTEN causes learning and memory deficits and disrupts adult neurogenesis with accompanying lactate accumulation. Consistently, administering lactate to wild-type animals impairs adult hippocampal neurogenesis. The endothelial PTEN/Akt pathway increases monocarboxylic acid transporter 1 (MCT1) expression to enhance lactate transport across the brain endothelium. Moreover, cerebrovascular overexpression of MCT1 or deletion of Akt1 restores MCT1 expression, decreases lactate levels, and normalizes hippocampal neurogenesis and cognitive function in PTEN mutant mice. Together, these findings delineate how the brain endothelium maintains lactate homeostasis and contributes to adult hippocampal neurogenesis and cognitive functions.