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To address the issues of low ratio of evanescent field (γ) and high reflectivity between waveguide cross‐section and gas for the mid‐infrared waveguide sensors, we propose a chalcogenide (ChG) suspended waveguide with Ge28Sb12Se60 as the core layer and silica (SiO2) as the buffer layer. The SiO2 beneath the waveguide core ridge structure is removed to create suspended structure. The waveguide sensing performance is obtained using a 10% methane (CH4) sample. The fabricated waveguide exhibits a γ of 112%, which is a 10% improvement compared to a free‐space optical sensor with the same optical path length. The good agreement between the theoretical and experimental results of γ confirms the reliability of our theoretical investigation approach. The influences of fabrication error, environmental temperature, and pressure on sensing performances are discussed. This work provides theoretical guidance for designing waveguide structures with large γ, contributing to the further enhancement of on‐chip sensor performance. [ABSTRACT FROM AUTHOR]

This paper introduces a new thunderstorm identification algorithm called combinatorial 8‐connectivity method based on total lightning activity as observed by the Foshan total lightning location system. The influence of spatio‐temporal parameters on the outcome is presented. The evaluation method contains four criteria: the fitting area of lightning clusters, the area proportion of lightning clusters, the number of lightning clusters and the utilization rate of lightning events. It is found that the fitting area adopting grid cells with size 0.02°–0.05° remains constant around 4, 9, 16 and 25 times those using grid cells of 0.01° in size, respectively. The evaluation criteria change by less than 0.61 km2/min in area, less than 0.43%/min in area proportion, less than 1/min in number and less than 2.8% in utilization rate using 0.01° grid cell when the duration of time interval exceeds 6 min and the spatial gap between grid cells with lightning events is more than 2 gaps. Then, the evaluation results of the combined 8‐connectivity method are compared with the results of the connected‐component labeling method (8, 24, 48, 80 and 120‐connectivity method), and it is found that the performance of combined 8‐connectivity method is better to outline lightning cluster. The two methods have been applied to case analysis on 15 May 2014. Key Points: Due to the random distribution of total lightning data, a thunderstorm identification algorithm is introducedAn identification evaluation method is introduced to analyze the performance of different methodsAccording to the analysis of spatiotemporal parameters, stable spatiotemporal parameters are selected to identify lightning clusters [ABSTRACT FROM AUTHOR]

On‐chip waveguide spectroscopic sensors have attracted considerable attention due to its potential for large‐scale integration. However, existing waveguide gas sensors based on direct absorption spectroscopy (DAS) suffer from limited sensitivity and measurement range. Here waveguide‐based on‐chip photothermal spectroscopy (PTS) is demonstrated for gas detection with high sensitivity and large dynamic range. On‐chip photothermal field due to non‐radiation relaxation of gas molecules and the resulted photothermal phase modulation are analyzed. By selecting chalcogenide glass (ChG) as the core‐layer material and fabricating thermally‐isolated ChG‐on‐SU8 waveguide for thermal field accumulation, a twofold increase in photothermal phase modulation is achieved as compared to ChG‐on‐SiO2 waveguides. Different from the major concern of multi‐path etalon noise in DAS, piezoelectric transducer noise in the interferometer is identified as the main source in this PTS. For a fair comparison, acetylene (C2H2) detection experiments are conducted using PTS and DAS with a 2 cm‐long ChG‐on‐SU8 waveguide. A remarkable sensitivity of 4 parts‐per‐million (ppm) is achieved, which is 16 times better than that of DAS. The dynamic range extends over five orders of magnitude for PTS, ≈3 orders of magnitude larger than that of DAS. Such high performance opens the possibility of fully‐integrated chip‐level sensors for low‐power, light‐weight applications. [ABSTRACT FROM AUTHOR]

Soybean residue has caused pollution to the environment due to high output. Herein, in order to reutilization soybean residue, a novel soybean hulls residue based hierarchically porous carbon was prepared by one‐step carbonization‐activation, and its structure and micromorphology were characterized by SEM, FT‐IR, Raman, TEM, BET and XPS. Based on results of characterization, which illustrated typical hierarchically pore structure with pore sizes are 1000 nm, 300 nm and 1.4 nm. The specific surface area and total pore volume were corresponded to 1455.41 m2/g and 0.731 cm3/g, respectively. And the pore‐forming mechanism was discussed in raw materials is a pyrolysis process. Furthermore, it was found that adsorption capacity of dye could got to 625 mg/g in 30 min when the adsorbent was 0.05 g. In summary, the soybean hulls residue based hierarchically pore material with large surface area and rich in pore structure, which will exhibit excellent performance towards wastewater treatment. [ABSTRACT FROM AUTHOR]

Near‐infrared (NIR) organic photodetectors (OPDs) are competitive candidates for flexible electronics in biomedical imaging and optical communications applications. However, current OPDs still suffer from a low detectivity beyond 1000 nm and a high dark current at bias due to the lack of high‐performance narrow‐bandgap non‐fullerene acceptors (NFAs). In this study, spiro‐conjugated core donor (D) unit is adopted to construct NFAs, SPT‐4F and tSPT‐4F. Comparing with PT‐4F without spiro‐conjugation, the orthogonal spiro‐conjugated planes endow SPT‐4F and tSPT‐4F with more rigid conformation and thus superior intermolecular stacking, resulting in the enhanced absorption beyond 1000 nm. Impressively, tSPT‐4F based device gives the best performance with a dark current of 4.52 × 10−10 A cm−2 under reversed bias of −0.1 V, an external quantum efficiency (EQE) response over 48% at 1010 nm, a detectivity of 1.25 × 1013 Jones and a responsibility of 0.40 A W−1 at 1010 nm. To the best of the authors' knowledge, this is one of the best performed devices reported to date for binary NIR OPDs with response beyond 1000 nm. This study provides a feasible molecular design strategy to develop narrow‐bandgap NFAs with spiro‐conjugation for highly detective NIR OPDs. [ABSTRACT FROM AUTHOR]

A novel double‐slot subwavelength grating with high sensitivity and small size was presented for the detection of carbon dioxide (CO2). Compared with single‐slot structure, the proposed double‐slot structure reduces the influence of slot width on the transmission intensity and thus improves the sensor performance. For enabling selectivity and sensitivity, the gap of the grating is filled with polyhexamethylene biguanide (PHMB). The refractive index of PHMB decreases after the absorption of CO2 molecules, which changes the effective refractive index of the waveguide mode. For getting the highest sensitivity, the proposed sensor was numerically simulated and optimized. The limit of detection for CO2 can be as low as 6.3 parts per million (ppm), which is lower than other reported waveguide CO2 sensors based on PHMB. The proposed sensor is capable of atmospheric CO2 monitoring with an acceptable limit of detection. [ABSTRACT FROM AUTHOR]

Review: 118 refs. [ABSTRACT FROM AUTHOR]

Entitled 1,4-benzodiazepines are of particular interest in drug design. [ABSTRACT FROM AUTHOR]

Review: 46 refs. [ABSTRACT FROM AUTHOR]

Four diakylimidazolium ionic liquids, namely 1-alkyl-3-dodecylimidazolium bromides ([CCim]Br) with the same dodecyl long-chain tail (C) and the short alkyl side chain (C, n = 1-4), were synthesized, and their molecule structures were confirmed by ESI-MS, H-NMR and elemental analysis. The physicochemical properties of [CCim]Br ( n = 1-4) were determined by means of surface tension and fluorescence probe methods, respectively. It was found that elongation of the side chain length will bring about an enhancement of surface activity. Along with the side chain length increasing, the critical micelle concentration (CMC), surface tension at CMC ( γ), the maximum surface excess (Γ), micellar aggregation number ( N) and micellar microenvironment polarity of [CCim]Br decrease, while adsorption efficiency (p C), surface pressure at CMC (Π), the minimum molecular cross-sectional area ( A) at air-solution interfaces and CMC/ C ratio increase. [ABSTRACT FROM AUTHOR]

Abstract: Hyperglycolysis, observed within the penumbra zone during brain ischemia, was shown to be detrimental for tissue survival because of lactate accumulation and reactive oxygen species overproduction in clinical and experimental settings. Recently, mounting evidence suggests that glycolytic reprogramming and induced metabolic enzymes can fuel the activation of peripheral immune cells. However, the possible roles and details regarding hyperglycolysis in neuroinflammation during ischemia are relatively poorly understood. Here, we investigated whether overactivated glycolysis could activate microglia and identified the crucial regulators of neuroinflammatory responses in vitro and in vivo. Using BV 2 and primary microglial cultures, we found hyperglycolysis and induction of the key glycolytic enzyme hexokinase 2 (HK2) were essential for microglia‐mediated neuroinflammation under hypoxia. Mechanistically, HK2 up‐regulation led to accumulated acetyl‐coenzyme A, which accounted for the subsequent histone acetylation and transcriptional activation of interleukin (IL)‐1β. The inhibition and selective knockdown of HK2 in vivo significantly protected against ischemic brain injury by suppressing microglial activation and IL‐1β production in male Sprague–Dawley rats subjected to transient middle cerebral artery occlusion (MCAo) surgery. We provide novel insights for HK2 specifically serving as a neuroinflammatory determinant, thus explaining the neurotoxic effect of hyperglycolysis and indicating the possibility of selectively targeting HK2 as a therapeutic strategy in acute ischemic stroke. [ABSTRACT FROM AUTHOR]

Amphibious carbon dots (CDs) are prepared by a rapid microwave method; they emit strong yellow emission in H2O, CHCl3, and a polymer matrix. The CDs can be used as a colorimetric nanosensor for the discrimination of Cr(III) and Cr(VI) [ABSTRACT FROM AUTHOR]

In this paper, fluorescent carbon dots (CDs) loaded on silica (SiO2) spheres are synthesized by the one-pot hydrothermal route, and then folic acids (FA) are covalently conjugated on the surface of SiO2 spheres. The formed SiO2@CDs-FA composites can target specific tissues, e.g., cancer. The key of this method is the employment of (3-aminopropyl)trimethoxysilane as bridge joint, which not only serves as surface passivation agents allowing the large scale synthesis of CDs with high quantum yield, but also enables SiO2@CDs composites further covalent conjugation of FA. The resultant SiO2@CDs composites have many advantages such as easy separation and purification, highly stable, well water-soluble, and biocompatible. Moreover, the SiO2@CDs-FA could be used as fluorescent probes for biological imaging in vitro. The uptake of the SiO2@CDs-FA into HeLa cells is receptor-mediated endocytosis, which is confirmed by a comparative study using FR-negative 293T cells. Findings from this study suggest that the SiO2@CDs-FA composites could be used as a platform for cancer diagnosis studies in various biological systems. [ABSTRACT FROM AUTHOR]

Strawberry‐like and fluorescent SiO2@CDs composites are prepared by a facile hydrothermal route at gram scale by C. Wang, C. Zhang, and co‐workers in work described on page 944. The resulting composites have numerous advantages, including high stability, good biocompatibility, and easy purification. Moreover, composites further functionalized by folic acid (FA) can be used as probes for targeted labeling of cancer cells. [ABSTRACT FROM AUTHOR]