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Recasting is the adult rephrasing of a child's immediately preceding utterance. It has been shown to have outstanding effects on promoting language development in autistic children. This study used lag sequential analysis to explore the impact of mothers' conversational styles on the communicative behavior of autistic children when using recasting. This study recruited 30 Chinese autistic children (aged 3–6 years) and their mothers. The utterances of the children and their mothers during 30‐min interactions were transcribed, coded, and analyzed. The mothers' conversational styles were determined by the percentages of child‐dominant, mother‐dominant, and equality styles. The results indicated that mothers' conversational styles were predominantly child‐dominant, differing from the expected mother‐dominant style that is typical in Eastern cultures and traditions. However, some mothers still demonstrated a significant proportion of mother‐dominant style in their conversation, while some exhibited a considerable amount of equality style. Moreover, mothers with a mainly child‐dominant style and minimal use of mother‐dominant and equality styles used recasting after the child's response, triggering the child to initiate new topics. Mothers with a child‐dominant style combined with prominent mother‐dominant features implemented untargeted self‐recasting, the children did not respond significantly. Mothers with a child‐dominant style combined with prominent equality features used recasting after the children responded, initiated, or expanded the conversation, which often facilitated the child's expansion of the conversation. These findings provide suggestions for designing parent‐mediated early language interventions for autistic children. Lay Summary: Conversational interaction styles of Chinese mothers and their autistic children were characterized by child‐dominant conversation. Mothers with different conversational styles applied recasting differently, with different effects on their children's language expansion behavior. These findings provide suggestions for designing parent‐mediated early language interventions for autistic children. [ABSTRACT FROM AUTHOR]

This study presents insights into the use of activated Al2O3 ${\text{Al}}_{2}{{\rm{O}}}_{3}$ catalysts to improve the energy efficiency of NOx ${\text{NO}}_{x}$ production in atmospheric pressure air plasma. The introduction of catalysts in the direct current glow discharge system reduces the energy cost of NOx ${\text{NO}}_{x}$ production by up to 45% at low gas flow rates. Notably, even when positioned away from the plasma zone, the catalyst enhanced NOx ${\text{NO}}_{x}$ production, suggesting a significant role for the catalytic activation of downstream neutral species. The study also introduced a novel approach involving an air plasma jet infused with floating catalyst powder. This method significantly increased energy efficiency at higher discharge currents, with an associated energy cost of 2.9 MJ/mol for NOx ${\text{NO}}_{x}$ production. [ABSTRACT FROM AUTHOR]

Reducing mechanical losses and suppressing self‐heating are critical characteristics for high‐power piezoelectric applications. For environmentally friendly Pb‐free piezoelectric ceramics, traditional acceptor doping or annealing treatments have successfully improved the mechanical quality factor (Qm) based on a ceramic matrix with a poor piezoelectric coefficient (d33<100 pC/N). Nevertheless, a ceramic with high Qm and d33 values has not been reported owing to the inverse relationship between Qm and d33. Herein, a novel hardening method called grain boundary diffusion is used to develop Pb‐free potassium sodium niobate ceramics, where Qm increased by more than two‐fold (from 51 to 132) and a high d33 value (d33 = 360 pC/N) is maintained. Significantly, d33 retained 98% of its initial value after 180 days, exhibiting improved aging stability. The established properties are associated with the formation of the core‐shell microstructure and the full gradient composition distribution using structural characterizations and phase‐field simulations, where the core maintains a high d33 and the shell provides a hardening effect. The novel hardening effect in piezoelectric materials, known as grain boundary diffusion hardening, highlights the enhancement of the mechanical quality factor with high piezoelectricity, providing a new paradigm for the design of functional materials. [ABSTRACT FROM AUTHOR]

Radiosensitizers hold great promise for enhanced cancer radiotherapeutics. However, apoptosis evasion of cancerous cells usually limits the efficiency of radiosensitive strategies. Herein, an in situ self‐assembled supramolecular antagonist is developed to reinforce the treatment outcome of radiotherapy by inhibiting tumor apoptosis evasion. The supramolecular antagonist is composed of self‐assembled peptide functionalized with apoptosis‐inducing peptide SmacN7 and alkaline phosphatase (ALP)‐responsive group. Upon reaching the tumor site, the supramolecular antagonist can in situ form membrane‐localized nanofibers triggered by ALP overexpressing in tumor cells, leading to enhanced cellular internalization. As a result, the cell‐permeable supramolecular antagonist effectively binds to the inhibitor of apoptosis proteins (IAPs) and eliminates their inhibitory effect on caspase activity, thereby remarkably blocking the apoptosis evasion of tumor cells and boosting the therapeutic efficacy of radiotherapy. Furthermore, in vivo studies confirm that treatment with in situ self‐assembled supramolecular antagonists can enhance radiation‐induced tumor destruction without perceptible systemic toxicity. This study offers a novel strategy of tumor apoptosis evasion inhibition to potentiate radiotherapy, which may be instructive to the development of advanced cancer therapies. [ABSTRACT FROM AUTHOR]

Low back pain (LBP) is a leading cause of labour loss and disability worldwide, and it also imposes a severe economic burden on patients and society. Among symptomatic LBP, approximately 40% is caused by intervertebral disc degeneration (IDD). IDD is the pathological basis of many spinal degenerative diseases such as disc herniation and spinal stenosis. Currently, the therapeutic approaches for IDD mainly include conservative treatment and surgical treatment, neither of which can solve the problem from the root by terminating the degenerative process of the intervertebral disc (IVD). Therefore, further exploring the pathogenic mechanisms of IDD and adopting targeted therapeutic strategies is one of the current research hotspots. Among the complex pathophysiological processes and pathogenic mechanisms of IDD, oxidative stress is considered as the main pathogenic factor. The delicate balance between reactive oxygen species (ROS) and antioxidants is essential for maintaining the normal function and survival of IVD cells. Excessive ROS levels can cause damage to macromolecules such as nucleic acids, lipids, and proteins of cells, affect normal cellular activities and functions, and ultimately lead to cell senescence or death. This review discusses the potential role of oxidative stress in IDD to further understand the pathophysiological processes and pathogenic mechanisms of IDD and provides potential therapeutic strategies for the treatment of IDD. [ABSTRACT FROM AUTHOR]

Non‐invasive detection and precise localization of deep lesions have attracted significant attention for both fundamental and clinical studies. Optical modality techniques are promising with high sensitivity and molecular specificity, but are limited by shallow tissue penetration and the failure to accurately determine lesion depth. Here the authors report in vivo ratiometric surface‐enhanced transmission Raman spectroscopy (SETRS) for non‐invasive localization and perioperative surgery navigation of deep sentinel lymph nodes in live rats. The SETRS system uses ultrabright surface‐enhanced Raman spectroscopy (SERS) nanoparticles with a low detection limit of 10 pM and a home‐built photosafe transmission Raman spectroscopy setup. The ratiometric SETRS strategy is proposed based on the ratio of multiple Raman spectral peaks for obtaining lesion depth. Via this strategy, the depth of the phantom lesions in ex vivo rat tissues is precisely determined with a mean‐absolute‐percentage‐error of 11.8%, and the accurate localization of a 6‐mm‐deep rat popliteal lymph node is achieved. The feasibility of ratiometric SETRS allows the successful perioperative navigation of in vivo lymph node biopsy surgery in live rats under clinically safe laser irradiance. This study represents a significant step toward the clinical translation of TRS techniques, providing new insights for the design and implementation of in vivo SERS applications. [ABSTRACT FROM AUTHOR]

Noninvasive detection of deep lesions remains a long‐standing goal for clinical applications, with depth estimation of a single lesion in heterogeneous tissues being a key challenge. Currently, optical techniques are widely applied for lesion detection, but they face difficulties in achieving rapid and precise lesion depth estimation, particularly when the lesions are buried in thick heterogeneous tissues and the applied irradiance is below clinically maximum permissible exposure. Herein, we theoretically and experimentally demonstrate a universal method for depth prediction of phantom lesions labeled with surface‐enhanced Raman scattering nanotags in thick biological tissues using ratiometric transmission Raman spectroscopy (TRS). We begin by highlighting the linear relationship between the natural logarithm of Raman peak‐to‐peak ratio and the lesion depth and establishing a home‐built TRS system with the clinically safe irradiance. We achieve an accurate depth prediction for phantom lesions hidden in 6‐cm‐thick ex vivo homogeneous tissue with a root mean squared error (RMSE) as low as 2.42%. Additionally, we predict the depth of phantom lesions buried in 5‐cm‐thick ex vivo heterogeneous tissues with an RMSE of down to 8.35%. We also demonstrate the applicability of this method theoretically for highly heterogeneous tissues such as complex in vivo environments. This work provides a rapid, robust, and universal method to estimate the depth of lesions in complex biological samples, demonstrating the potential of ratiometric Raman spectroscopy for lesion localization in clinical applications. [ABSTRACT FROM AUTHOR]

SUMMARY: PROTEIN l‐ISOASPARTYL O‐METHYLTRANSFERASE (PIMT) affects seed vigor by repairing damaged proteins. While PIMT is capable of isoaspartyl (isoAsp) repair in all proteins, those proteins most susceptible to isoAsp formation have not been well characterized, and the mechanisms by which PIMT affects seed vigor remain largely unknown. Using co‐immunoprecipitation and LC‐MS/MS, we found that maize (Zea mays) PIMT2 (ZmPIMT2) interacted predominantly with both subunits of maize 3‐METHYLCROTONYL COA CARBOXYLASE (ZmMCC). ZmPIMT2 is specifically expressed in the maize embryo. Both mRNA and protein levels of ZmPIMT2 increased during seed maturation and declined during imbibition. Maize seed vigor was decreased in the zmpimt2 mutant line, while overexpression of ZmPIMT2 in maize and Arabidopsis thaliana increased seed vigor upon artificial aging. ZmPIMT2 was localized in the mitochondria, as determined by subcellular localization assays using maize protoplasts. ZmPIMT2 binding to ZmMCCα was confirmed by luciferase complementation tests in both tobacco (Nicotiana benthamiana) leaves and maize protoplasts. Knockdown of ZmMCCα decreased maize seed aging tolerance. Furthermore, overexpression of ZmPIMT2 decreased the accumulation of isoAsp of ZmMCCα protein in seed embryos that underwent accelerated aging treatment. Taken together, our results demonstrate that ZmPIMT2 binds ZmMCCα in mitochondria, repairs isoAsp damage, and positively affects maize seed vigor. Significance Statement: PROTEIN l‐ISOASPARTYL METHYLTRANSFERASE (PIMT) positively affects orthodox seed vigor, repairing abnormal protein isoaspartate (isoAsp) to Asp; however, how seed vigor is exactly affected remains unclear. Maize (Zea mays) mitochondrial 3‐METHYLCROTONYL COA CARBOXYLASE (ZmMCC) positively influences seed vigor, yet accrues isoAsp. ZmPIMT2, also mitochondrially localized, interacts with, and repairs, the isoAsp‐damaged ZmMCC. These results have led to a better understanding of the foundations of seed vigor. [ABSTRACT FROM AUTHOR]

A series of piperazine derivatives containing bis‐isoxazole were successfully synthesized by the reaction between piperazine and substituted isoxazole derivatives under the optimal reaction condition. The structures of all products were confirmed by IR, HRMS, 1H and 13C NMR. The antibacterial activities of all products against Mycobacteria smegmatis in vitro were tested using rifampin as a positive control. Two compounds presented wonderful anti‐mycobacterium activity, and their minimum inhibitory concentrations were respectively 2.60±1.11 μmol/mL and 4.35±0.00 μmol/mL, which indicated that they can be regarded as candidates for development of anti‐TB drugs. [ABSTRACT FROM AUTHOR]

An efficient and convenient synthesis of 2‐substituted benzimidazoles catalyzed by magnetic Fe3O4 supported by modified bentonite (MB) was developed. Herein, a separable, magnetic catalyst Fe3O4/MB was successfully prepared on the basis of exploring Fe3O4 synthesis by co‐precipitation method. Fe3O4 was obtained in 96.09 % yield using sweet orange oil as a reducing and protecting agent. The result showed that the sweet orange oil played a crucial role in the preparation of Fe3O4. Fe3O4 and Fe3O4/MB were characterized by powder XRD, SEM, EDX, XPS and BET, and were further applied to catalyze the synthesis of 2‐substituted benzimidazoles. The applicability of the substrate was investigated on the basis of optimizing the reaction conditions. As a consequence, 2‐substituted benzimidazoles were obtained in 37.01–91.68 % yield. It suggested that Fe3O4/MB was an environmentally friendly and low‐cost catalyst possessing good catalytic activity, broader substrate adaptability and excellent recyclability. It is a promising catalyst in industrial production. [ABSTRACT FROM AUTHOR]

An efficient synthesis of 3‐methyl‐4‐(arylmethylene)isoxazol‐5(4H)‐ones are developed via cyclocondensation in 84–94 % yields starting from aromatic aldehydes, hydroxylamine with ethyl acetoacetate vitamin B1 is catalyzed under ultrasound radiation, and are characterized by HR‐MS, FT‐IR and 1H and 13C NMR spectroscopy. The reaction has simple operation, metal‐free catalysis, acid or base free catalysis. As a green catalyst, vitamin B1 is found to possess favorable catalytic activity and reusability for the condensation reaction. 5‐(2‐Hydroxy‐3‐methoxybenzylidene)‐3‐methylisoxazol‐5(4H)‐one as a metal ion fluorescent probe, has excellent selectivity to Sr2+ and exhibits obvious discoloration. Fe2+ quenches the fluorescence of the ligand 3‐methyl‐4‐(2,3,4‐trihydroxybenzylidene)isoxazol‐5(4H)‐one, and exhibits an obvious color change. [ABSTRACT FROM AUTHOR]

Niobate‐based lead‐free piezoceramics have attracted wide attention due to their excellent piezoelectric properties. Although the temperature sensitivity of piezoelectricity or strain in one sample has been solved to a certain extent, how to simultaneously improve the temperature stability of both in one sample is still an issue. Herein, by constructing multilayer composite ceramics and doping Ho element, both improved piezoelectric and strain temperature stability (the variations are below 3% under 30–100 °C) are achieved, showing great property advantage compared with previous reports. Different from the compositionally graded composite ceramic design, the Ho doping can not only increase orthorhombic‐tetragonal phase transition temperature (TO‐T) and then create the condition for the formation of successive phase transition, but also stabilize the oriented domain state. Therefore, the excellent temperature stability of both piezoelectricity and strain can be attributed to the multistep phase transition induced by the multilayer design, the fine regulation of TO‐T interval by the optimization of lamination combination, and the stabilized polarization induced by Ho doping. The new strategy for solving both piezoelectric and strain temperature sensitivity can further promote the commercial application of potassium sodium niobate‐based lead‐free piezoelectric ceramics. [ABSTRACT FROM AUTHOR]

The detection of deep‐seated lesions is of great significance for biomedical applications. However, due to the strong photon absorption and scattering of biological tissues, it is challenging to realize in vivo deep optical detections, particularly for those using the safe laser irradiance below clinical maximum permissible exposure (MPE). In this work, the combination of ultra‐bright surface‐enhanced Raman scattering (SERS) nanotags and transmission Raman spectroscopy (TRS) is reported to achieve the non‐invasive and photosafe detection of "phantom" lesions deeply hidden in biological tissues, under the guidance of theoretical calculations showing the importance of SERS nanotags' brightness and the expansion of laser beam size. Using a home‐built TRS system with a laser power density of 0.264 W cm−2 (below the MPE criteria), we successfully demonstrated the detection of SERS nanotags through up to 14‐cm‐thick ex vivo porcine tissues, as well as in vivo imaging of "phantom" lesions labeled by SERS nanotags in a 1.5‐cm‐thick unshaved mouse under MPE. This work highlights the potential of transmission Raman‐guided identification and non‐invasive imaging toward clinically photosafe cancer diagnoses. [ABSTRACT FROM AUTHOR]

The popularity of renewable energy distributed generation has increased for environmental and convenient concerns. However, the occurrence of the above situation will cause the communication resources of the microgrid to be rapidly consumed to maintain the frequency stability of the system. In this work, a novel event‐triggered scheme is developed to ameliorate the present communication networks of island microgrid with communication delay. Combining the newly constructed Lyapunov–Krasovskii functional and the convex combinatorial method, the asymptotic stability of a typical microgrid is demonstrated. Moreover, taking dynamic switching system into account, the two‐part proof is completed independently. Then, a positive inter‐execution time lower bound is implemented to guarantee that there is no Zeno behaviour. Finally, the numerical simulation results are compared with other sampling methods in different scenarios. It indicates that the proposed scheme is superior to other types of scheme in frequency response performance and communication burden. [ABSTRACT FROM AUTHOR]

Under global warming, the frequent occurrence of Eurasian extreme cold events in the Northern Hemisphere in recent years has attracted widespread attention. Winter Eurasia near‐surface anticyclone activities are closely related to low temperatures. This study uses a new objective anticyclone identification algorithm based on a Mask region‐based convolutional neural network (Mask R‐CNN) to detect long‐term winter Eurasian anticyclone activities. We found that most tracks of Eurasian anticyclones (30.5%) pass Siberia in winter. Anticyclone tracks over Siberia can be well separated into the eastward moving type, the northwest–southeast type, and the local type, with distinct associated circulation patterns. The energy dispersions of upstream Rossby waves have an important influence on the movement, maintenance and intensification of the three types. In association with anticyclones intensifying in Siberia, surface air temperatures in the mid‐latitudes of Eurasia, especially Siberia, are significantly lower. In particular, the local type is the most active (56.1%) and is significantly correlated with the winter temperature anomaly in most areas of East Asia. Further research indicates that the preceding autumn sea ice condition in the Barents Sea can be used as a precursor factor to modulate the local type anticyclone activity and winter temperature anomaly in East Asia. In years of less ice, a quasi‐meridional wave activity flux originating from the Barents Sea is more active, and the centre SLP of the local type anticyclone is higher with more cold air mass carried, which in turn results in colder weather in Siberia, the Mongolian Plateau and East Asia. [ABSTRACT FROM AUTHOR]

Upscaling efficient and stable perovskite materials is vital for metal halide perovskite solar cells (PSCs) and additive engineering contributes a lot to making high‐quality PSCs. While the recent examples involved mixing dimethylammonium (DMA) cation has been employed for the fabrication of all‐inorganic perovskites with improved efficiency and stability, the role of DMA cation in hybrid perovskite (formamidinium lead triiodide, denoted as FAPbI3) remains inconclusive. Herein, DMA cations are substituted for FA sites of Cs0.12FA0.88PbI3 for printable triple mesoscopic PSCs and shed lights on the roles and mechanism of DMA in the perovskite. It is found that a small amount of DMA is doped into the perovskite lattices, meanwhile, an intermediate compound DMAPbI3 is formed and exists at grain boundaries, which improves the crystallinity of perovskite films and reduces nonradiative recombination through a passivation role. With these benefits, the best‐performing printable PSC attained a power conversion efficiency of 17.46%. Unencapsulated devices maintained over 96% of the initial efficiencies in ambient condition for 960 h and 95% of the initial efficiencies after 360 h under continuous thermal aging at 85 °C in N2 atmosphere. [ABSTRACT FROM AUTHOR]

When the correlation of wind power output among wind farms is not considered, the integrated stochastic characteristics of wind power will not be captured accurately. Using this inaccurate feature may lead to an impractical even a failing result of unit commitment (UC). Therefore, this paper proposes a multiple correlations model for wind power forecast errors (WPFEs), and to capture this multiple correlation feature in UC problem, a two‐stage chance‐constrained interval UC (CIUC) model is proposed. First, an analytical expression of multiple correlations, including spatial, temporal and conditional correlations, is presented to improve the description accuracy of stochastic WPFEs. To strike a balance between risk and operational cost, a chance‐constrained decision method is developed to optimize the time‐varying interval of wind power output in the first stage. Subsequently, an interval UC model is established to determine the optimal operational schedule in the second stage. Finally, the proposed CIUC model is solved using a solution strategy that combines column‐and‐constraint generation and sample average approximation. The effectiveness and practicality of the proposed method are verified via the numerical results for IEEE 39‐bus and 118‐bus systems. [ABSTRACT FROM AUTHOR]

Applying metal–organic framework (MOF) materials to perovskite solar cells (PSCs) is an innovative and promising direction in the current photovoltaic field, especially in low‐cost carbon‐based PSCs without hole transport layer. Herein, a novel mesoporous anatase TiO2 nanocrystalline with pie morphology, large specific surface area (SSA), and outstanding wettability is successfully prepared by sintering the NH2‐MIL‐125 at 500 °C for 6 h. The TiO2 derived from NH2‐MIL‐125 possesses excellent penetration and crystallinity of perovskite in the electron transporting layer (ETL), and exhibits appropriate work function which matches relatively better with the conduction band of perovskite. Meanwhile, the power conversion efficiencies (PCEs) of the two PSC devices based on the as‐prepared TiO2 are 13.49% and 12.55%, respectively. Moreover, both of these devices exhibit good stability. [ABSTRACT FROM AUTHOR]

Based on the design concept of 'strong horizontal joint and weak vertical joint', an energy‐dissipating fabricated shear wall structure system with a steel damper is proposed. The wall limbs were connected using the damper to realize the rapid assembly and improve the seismic performance of the fabricated shear wall structure. Four fabricated shear wall specimens and one cast‐in‐place comparison specimen were prepared, and a low‐cycle repeated load test was carried out under an axial compression ratio of 0.1. Results show that the fabricated shear wall structure features slightly reduced bearing capacity but obviously improved ductility, and the energy dissipation of the damper improves the seismic performance of the structure. The damper can dissipate energy rapidly, reduce the damage degree of the wall limbs and work stably, suggesting its good performance as a connector. [ABSTRACT FROM AUTHOR]

Surface defects, which mediate nonradiative recombination, are detrimental to both the photovoltaic performance and stability of perovskite solar cells (PSCs). Improving photovoltage and fill factor (FF) in screen‐printed mesoporous PSCs is a major challenge for approaching the power conversion efficiency (PCE) of the planar configured devices. Herein, a novel bifacial passivation strategy which simultaneously suppresses deep trap states within TiO2 and perovskite through interaction between functional groups and defects is demonstrated for fully printable mesoscopic PSCs. The application of monoethanolamine (MEA) treatment to TiO2 surface not only reduces the energy barrier between TiO2 and perovskite for accelerating the charge transfer but also passivates the uncoordinated Pb defects on the perovskite interface. Due to the synergistic effect of charge extraction promotion and trap passivation, the fabricated PSCs deliver a champion PCE of 15.5% with an enhanced Voc of 0.94 V and FF of 70.4% compared with PSCs without MEA passivation, and the device maintains 97% of its topmost PCE after 240 h under constant simulated solar illumination in air atmosphere. This investigation helps exploit new approaches for defect passivation to further improve both the efficiency and stability of printable mesoscopic PSCs. [ABSTRACT FROM AUTHOR]

Finding a global optimal solution to the distribution network reconfiguration (DNR) problem in a short time is a challenging task. This study proposes a real‐time online data‐driven DNR (3DNR) method. Power loss minimisation, lowest bus voltage maximisation and reliability maximisation are taken as objectives. First, in this study, a methodology combining heuristic algorithm and metaheuristic algorithm to solve DNR is proposed. Then a set of data that satisfies the data drive model requirements is obtained. Next, the improved convolution neural network is used to train the data set of DNR. Unlike the state‐of‐art methods, the proposed 3DNR can realise the real‐time online reconfiguration without power flow calculation. The feasibility and effectiveness of the proposed method are demonstrated on IEEE‐34, IEEE‐123, and a practical distribution system in Taiwan. [ABSTRACT FROM AUTHOR]

Due to the remarkable properties of gold nanoparticles (AuNPs), they have been extensively employed as a potential tool for the diagnosis and treatment of cancers. While the conventional drug delivery system fails to efficiently deliver the chemotherapeutics due to the complexity of tumor microenvironment, people have been seeking alternative nanoparticulate strategy to improve the tumor specificity, the therapeutic index as wells as the pharmacokinetic profile. The nontoxic and nonimmunogenic nature, the high permeability, and superior retention effect of AuNPs provide additional benefits by enabling easy penetration and accumulation of drugs at the tumor sites. Here in this review, we focused on discussing the recent advances regarding the design of acid‐responsive AuNPs as well as their applications in drug/gene delivery and imaging in cancer diagnosis and therapy. Particularly, we highlighted the size switch strategies used in the development of acid‐responsive AuNPs. This article is categorized under:Diagnostic Tools > in vivo Nanodiagnostics and ImagingTherapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease [ABSTRACT FROM AUTHOR]

Summary: Raffinose is thought to play an important role in plant tolerance of abiotic stress. We report here that maize HEAT SHOCK FACTOR A2 (ZmHSFA2) and HEAT SHOCK BINDING PROTEIN 2 (ZmHSBP2) physically interact with each other and antagonistically modulate expression of GALACTINOL SYNTHASE2 (ZmGOLS2) and raffinose biosynthesis in transformed maize protoplasts and Arabidopsis plants. Overexpression of ZmHSFA2 in Arabidopsis increased the expression of Arabidopsis AtGOLS1, AtGOLS2 and AtRS5 (RAFFINOSE SYNTHASE), increased the raffinose content in leaves and enhanced plant heat stress tolerance. Contrary to ZmHSFA2, overexpression of ZmHSBP2 in Arabidopsis decreased expression of AtGOLS1, AtGOLS2 and AtRS5, decreased the raffinose content in leaves and reduced plant heat stress tolerance. ZmHSFA2 and ZmHSBP2 also interact with their Arabidopsis counterparts AtHSBP and AtHSFA2 as determined using bimolecular fluorescence complementation assays. Furthermore, endogenous ZmHSBP2 and Rluc, controlled by the ZmHSBP2 promoter, are transcriptionally activated by ZmHSFA2 and inhibited by ZmHSBP2 in maize protoplasts. These findings provide insights into the transcriptional regulation of raffinose biosynthetic genes, and the tolerance their product confers to plant heat stress. Significance Statement: Supraoptimal temperature is a major threat to plant productivity and survival. We found that maize HEAT SHOCK FACTOR A2 (HSFA2) and HEAT SHOCK BINDING PROTEIN 2 (HSBP2) antagonistically modulate expression of the GALACTINOL SYNTHASE gene in maize protoplast cells, and regulate both raffinose biosynthesis and plant heat stress tolerance in Arabidopsis. In addition, ZmHSBP2 is transcriptionally activated by ZmHSFA2 and inhibited by its own protein ZmHSBP2, elucidating control of protective oligosaccharide production in response to this abiotic stress. [ABSTRACT FROM AUTHOR]

Two‐dimensional layered MoSe2 has been proved to be promising electrocatalyst toward hydrogen evolution reaction (HER), although the typical disadvantages of poor conductivity and limited density of active sites in 2H‐phase restrict further development. Here, a clear evidence is presented in partially‐crystallized 2H‐MoS2xSe2(1‐x) nanosheets (NS) to demonstrate that: i) in both 2H‐ and 1T‐phase, single factor such as phase, conductivity, or defects will not determine or restrict the catalytic activity in MoSe2, and ii) synergistic tuning at least two factors will greatly enhance the overall HER performance than single factor no matter in 2H‐ or 1T‐MoSe2 crystal structures. The enhanced catalytic activity with η10=136 mV vs RHE, and a Tafel slope of 50 mV dec−1 are achieved in the optimized 2H‐MoS0.2Se1.8‐160 NS, which is the best among pure MoSSe materials without heterogeneous atom doping to our knowledge. In addition, 2H‐MoS0.2Se1.8/rGO anodes exhibit a stable reversible capacity of 396 mA h g−1 after 100 cycles at 0.5 A g−1. These discoveries provide a unique opportunity to comprehensively understand the single factor or multi‐factors mechanism for HER, which serves as the general design and modulation principles for further synthesize and applications of MoSe2‐based materials toward HER and other catalytic applications. [ABSTRACT FROM AUTHOR]

ABSTRACT: To develop colorless and soluble polyimide films, cis‐hydrogenated bisphenol A (cis‐HBPA) was successfully separated from HBPA isomers, and two novel monomers containing cis‐HBPA unit, 4,4′‐(4,4′‐isopropenylbicyclohexyloxy) diphthalic anhydride (HBPADA) and 4,4′‐(4,4′‐isopropenylbicyclohexyloxy) dianiline (f) were designed and synthesized. PI–(1 – 5) were achieved from HBPADA and five kinds of aromatic diamines and PI – 6 from HBPADA and semiaromatic diamine f via a two‐step thermal imidization. All the polyimides could afford flexible, tough, and transparent films with transparency as high as 86% at 450 nm. Surprisingly, the polyimides containing cis‐HBPA unit exhibited excellent solubility not only in polar solvents such as N, N‐dimethylacetamide, but also in low boiling solvents such as chloroform and dichloromethane. Additionally, analogues aromatic PI – 7 derived from 4,4′‐(hexafluoroisopropylidene)‐diphthalic anhydride (6FDA) and 2,2‐bis(4‐aminophenyl)hexafluoropropane (e) was obtained for comparison with PI–(1 – 6) on aspects of thermal, mechanical, soluble, optical, electrical, and morphological properties. The structure‐property relationships of PI–(1 – 7) were investigated in detail. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 2115–2128 [ABSTRACT FROM AUTHOR]

ABSTRACT: To carry out suspension polymerization of styrene in the presence of carbon black, an effective method was introduced to modify carbon black using nitric acid for oxygen treatment. The surface modification of carbon black with oxidation was confirmed by Fourier transform infrared spectroscopy, thermogravimetric analysis, and scanning electron microscopy (SEM), which demonstrated that the chemical structure of carbon black has clearly changed. Compared with pristine carbon black (CB), SEM illustrates that the aggregation phenomenon of modified carbon black (MCB) was clearly weakened. After modification, the aggregation and inhibition effects of MCB on the polymerization of polystyrene/modified CB (PS/MCB) composite particles are obviously weakened. The lipophilicity of CB after modification was also increased during the synthesis of PS/MCB. The oxidized CB was successfully dispersed by polystyrene using in situ suspension polymerization. The dispersion and dosage of MCB in PS/MCB composite particles was greatly improved over that of CB in PS/CB composite particles. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46387. [ABSTRACT FROM AUTHOR]

Graphene platelets reinforced zirconia ( GPLs/ZrO2) composites were prepared by spark plasma sintering in the present work. The effects of GPLs content on the densification route, microstructure feather, mechanical properties, and aging behaviors of such composites were investigated. In spite of the impeding effect of GPLs, high relative density of 98% was achieved for the composites owing to the uniform dispersion of GPLs. The addition of GPLs contributed to enhanced fracture toughness of the composites; when the added content was 1.0 wt.%, its fracture toughness reached up to 8.6 MPa·m1/2. Also, aging behavior of the GPLs/ZrO2 composites was investigated at 134°C for 24 hours. The monolithic ZrO2 ceramic and GPLs/ZrO2 composites presented residual ratio of 55% and 72% in fracture toughness, respectively. Thus, the incorporation of GPLs inhibited phase transformation from tetragonal phase to monoclinic phase of zirconia. [ABSTRACT FROM AUTHOR]

ABSTRACT Tuning the secondary structure of polypeptide is an effective strategy to modulate the assembly behaviors of polypeptide-based copolymers. In this study, ring-opening polymerization of l-alanine (Ala) and γ-benzyl- l-glutamate (BLG) N-carboxyanhydrides was adopted using mPEG-NH2 as the initiator to prepare mPEG-poly( l-alanine-co-γ-benzyl- l-glutamate) (PEAB) copolymers with various Ala to BLG ratios. 1H NMR spectra and GPC test confirmed their well-defined chemical structures. FT-IR spectra indicated that at the powder state, all copolymers adopted both β-sheet and α -helical conformations. With the content of PBLG increased, the crystallization temperature and melting points of PEAB copolymers first rose then fell indicated by DSC curves. The self-assembly of PEAB copolymers in dilute aqueous solution studied by DLS, TEM and circular dichroism spectra showed that PEAB copolymers self-assembled into nanostructures with diverse morphologies and sizes due to distinct polypeptide conformations. Rheological analysis indicated that the alteration of the polypeptide composition can effectively modulate the modulus of PEAB assemblies in concentrated solutions. In all, copolymerization of two hydrophobic amino acid N-carboxyanhydrides into the polypeptide block maybe an effective approach for modulating the assembly properties of PEGylated polypeptide. Besides, nanosilver-encapsulated PEA or PEAB hydrogel showed promising antibacterial effect against Staphylococcus aureus and Bacillus subtillis. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 1512-1523 [ABSTRACT FROM AUTHOR]

2D transition metal dichalcogenide (TMD) materials have been recognized as active platforms for surface-enhanced Raman spectroscopy (SERS). Here, the effect of crystal structure (phase) transition is shown, which leads to altered electronic structures of TMD materials, on the Raman enhancement. Using thermally evaporated copper phthalocyanine, solution soaked rhodamine 6G, and crystal violet as typical probe molecules, it is found that a phase transition from 2H- to 1T-phase can significantly increase the Raman enhancement effect on MoX2 (X = S, Se) monolayers through a predominantly chemical mechanism. First-principle density functional theory calculations indicate that the significant enhancement of the Raman signals on metallic 1T-MoX2 can be attributed to the facilitated electron transfer from the Fermi energy level of metallic 1T-MoX2 to the highest occupied molecular orbital level of the probe molecules, which is more efficient than the process from the top of valence band of semiconducting 2H-MoX2. This study not only reveals the origin of the Raman enhancement and identifies 1T-MoSe2 and 1T-MoS2 as potential Raman enhancement substrates, but also paves the way for designing new 2D SERS substrates via phase-transition engineering. [ABSTRACT FROM AUTHOR]

The increase of bacterial resistance demands rapid and accurate diagnosis of bacterial infections. Biosurface-induced supramolecular assembly for diagnosis and therapy has received little attention in detecting bacterial infections. Herein we present a dual fluorescent-nuclear probe based on self-assembly of vancomycin (Van) on Gram-positive bacteria for imaging bacterial infection. A Van- and rhodamine-modified peptide derivative (Rho-FF-Van), as the imaging agent, binds to the terminal peptide of the methicillin-resistant staphylococcus aureus (MRSA) and self-assembles to form nanoaggregates on the surface of MRSA. In an in vivo myositis model, Rho-FF-Van results in a significant increased fluorescence signal at the MRSA infected site. Radiolabeled with iodine-125, Rho-FF-Van shows strong radioactive signal in the MRSA-infected lungs in a murine model. This novel dual fluorescent and nuclear probe promises a new way for in vivo imaging of bacterial infections. [ABSTRACT FROM AUTHOR]

Aims/Introduction The aims of the present study were to evaluate the diagnostic value of fasting plasma glucose, 2-h postload plasma glucose and glycosylated hemoglobin (HbA1c) measurements in the screening of diabetes and prediabetes, and to determine the cut-off point of HbA1c in the diagnosis of diabetes and prediabetes in a Chinese population. Materials and Methods A total of 7,611 individuals aged 40 years or older, who did not have a prior history of diabetes, were randomly selected in the Changchun area. For each participant, a questionnaire was completed, and a physical examination and an oral glucose tolerance test were carried out. The values of fasting plasma glucose, 2-h postload plasma glucose and HbA1c were compared by area under the receiver operating characteristic curves. The Youden index was used to identify the optimal cut-off point of HbA1c in the diagnosis of diabetes and prediabetes. Results The prevalence of newly diagnosed diabetes and prediabetes was 12.71% and 29.39%, respectively. In participants with newly diagnosed diabetes, the area under the receiver operating characteristic curve was 0.8368 for fasting plasma glucose, 0.9330 for 2-h postload plasma glucose and 0.8064 for HbA1c; whereas for prediabetes, these values were 0.8022, 0.9288 and 0.6895, respectively. In addition, an HbA1c threshold of 6.3% showed the highest Youden index (0.4799) for detecting diabetes; furthermore, an HbA1c threshold of 5.8% showed the highest Youden index (0.2866) for detecting prediabetes. Conclusions HbA1c ≥6.3% (45 mmol/mol) and between 5.8% and 6.2% (40-44 mmol/mol) were the optimal cut-off values for the diagnosis of diabetes and prediabetes, respectively, in a Chinese population. [ABSTRACT FROM AUTHOR]

Hydroxyapatite ( HAp) hollow microspheres with hierarchically porous structure and nanorice-like architecture units were synthesized by the composite-hydroxide approach. NH4 H2 PO4 was first reacted with hydroxides to form a hydroxide-insoluble M3 PO4 (the term M represents either Na or K). The diffusing M3 PO4 at the liquid-solid interface then reacted with the Ca( OH)2, forming insoluble HAp hollow spheres by Kirkendall process. Results show that when reaction time is increased from 3 to 12 h, the average diameter of the microspheres increased from 2.64 to 4.16 μm. In addition, the size homogeneity of the hollow microspheres was improved gradually due to Ostwald ripening. The prepared hollow microspheres were treated by ultrasound, and nanorice-like component units with a large mass of mesopores (<10 nm) were displayed. These prepared HAp hollow microspheres might be expected to apply to ion adsorption and drug delivery. [ABSTRACT FROM AUTHOR]

Oligodendroglial injury is a pathological hallmark of many human white matter diseases, including multiple sclerosis (MS) and periventricular leukomalacia (PVL). Critical regulatory mechanisms of oligodendroglia destruction, however, remain incompletely understood. Ceramide, a bioactive sphingolipid pivotal to sphingolipid metabolism pathways, regulates cell death in response to diverse stimuli and has been implicated in neurodegenerative disorders. We report here that ceramide accumulates in reactive astrocytes in active lesions of MS and PVL, as well as in animal models of demyelination. Serine palmitoyltransferase, the rate-limiting enzyme for ceramide de novo biosynthesis, was consistently upregulated in reactive astrocytes in the cuprizone mouse model of demyelination. Mass spectrometry confirmed the upregulation of specific ceramides during demyelination, and revealed a concomitant increase of sphingosine and a suppression of sphingosine-1-phosphate, a potent signaling molecule with key roles in cell survival and mitogenesis. Importantly, this altered sphingolipid metabolism during demyelination was restored upon active remyelination. In culture, ceramide acted synergistically with tumor necrosis factor, leading to apoptotic death of oligodendroglia in an astrocyte-dependent manner. Taken together, our findings implicate that disturbed sphingolipid pathways in reactive astrocytes may indirectly contribute to oligodendroglial injury in cerebral white matter disorders. [ABSTRACT FROM AUTHOR]

Oxidative injury to premyelinating oligodendrocytes (preOLs) in developing white matter has been implicated in the pathogenesis of periventricular leukomalacia, the lesion underlying most cases of cerebral palsy in premature infants. In this study, we investigated the pathways of OL death induced by intracellular glutathione (GSH) depletion. We found that the lipoxygenase (LOX) inhibitors AA-861 and BMD-122 (N-benzyl-N-hydroxy-5-phenylpentamide; BHPP), but not the cyclooxygenase (COX) inhibitor indomethacin, fully protected the cells from GSH depletion caused by cystine deprivation. Arachidonic acid (AA), the substrate for 12-LOX, potentiated the toxicity of mild cystine deprivation and at higher concentration was itself toxic. This toxicity was also blocked by 12-LOX inhibitors. Consistent with a role for 12-LOX in the cell death pathway, 12-LOX activity increased following cystine deprivation in OLs. Blocking 12-LOX with AA-861 effectively inhibited the accumulation of reactive oxygen species (ROS) induced by cystine deprivation. These data suggest that, in OLs, intracellular GSH depletion leads to activation of 12-LOX, ROS accumulation and cell death. Mature OLs were more resistant than preOLs to cystine deprivation. The difference in sensitivity was not due to a difference in 12-LOX activity but rather appeared to be related to the presence of stronger antioxidant defense mechanisms in mature OLs. These results suggest that 12-LOX activation plays a key role in oxidative stress-induced OL death. [ABSTRACT FROM AUTHOR]

We investigated the mechanism of 3-morpholinosyndnomine (SIN-1) neurotoxicity in nearly pure neuronal cultures. In a simple saline solution, SIN-1 neurotoxicity was found to be mediated by peroxynitrite and independent of glutamate receptor activation[Y. Zhang&P.A. Rosenberg (2002)Eur. J. Neurosci,16, 1015–1024]. To further study the mechanism of peroxynitrite toxicity to neurons we investigated the role of caspases and poly (ADP-ribose) polymerase (PARP) in this model system. Ac-Tyr-Val-Ala-Asp-chloromethyl ketone (Ac-YVAD-cmk), a specific caspase-1 inhibitor, completely blocked neurotoxicity as well as ATP depletion induced by SIN-1. However, a caspase-3 inhibitor and a pan-caspase inhibitor were both without effect. These results suggested that the protection of Ac-YVAD-cmk might not be due to its inhibition of caspase-1. Indeed, Western blot analysis and assay of caspase activity indicated that caspase activation was not involved in SIN-1 toxicity. Ac-YVAD-cmk also completely blockedin vitroprotein nitration induced by SIN-1 or peroxynitrite, suggesting that Ac-YVAD-cmk may interact with peroxynitrite directly. Similarly, although activation of PARP is thought to be a major cause of peroxynitrite-induced ATP depletion, and two PARP inhibitors, 1,5-dihydroxyisoquinoline (DHQ) and 3-aminobenzamide (3-AB), completely prevented ATP depletion and neurotoxicity induced by SIN-1, SIN-1 did not increase poly (ADP-ribosyl)ation and PARP activity. Furthermore, DHQ and 3-AB completely preventedin vitroprotein nitration induced by peroxynitrite, indicating that DHQ and 3-AB directly interact with peroxynitrite. Taken together, these results suggest that in the model system used here peroxynitrite neurotoxicity is independent of caspase and PARP activation, and therefore implicate a novel mechanism. [ABSTRACT FROM AUTHOR]