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Photonic neuromorphic computing is a competitive paradigm to overcome the bottleneck of von Neumann architectures. Incoherent and coherent synaptic networks are two popular schemes realizing photonic weighting functions. Previous works have proved the distributed feedback (DFB) laser with an intracavity saturable absorber (DFB‐SA) can behavior like a spiking neuron. However, the compatibility with the incoherent synaptic architecture has not yet been demonstrated. Here the neuron‐like dynamics of a DFB‐SA laser subject to single‐wavelength and multiple‐wavelengths incoherent optical injections are experimentally demonstrated. The results show that, for the DFB‐SA laser subject to single‐wavelength incoherent injection, the neuron‐like dynamics including threshold, temporal integration, and refractory period are achieved. Besides, the range of injection wavelength that leads to a successful neuron‐like response is identified. For the DFB‐SA laser with four‐wavelength incoherent optical injection, the neuron‐like dynamics can also be achieved. In addition, the effect of wavelength interval is also considered. The logic XOR operation and Iris recognition tasks are successfully implemented. Furthermore, the feasibility of a cascaded system for the DFB‐SA lasers with four‐wavelengths incoherent optical injection is demonstrated. This work provides a feasible scheme for the system integration of photonic spiking neurons and incoherent synaptic networks. [ABSTRACT FROM AUTHOR]

Introduction: Diabetes has been recognized as an independent risk factor for periodontitis. Increasing evidences indicate that hyperglycemia aggravates inflammatory response of human periodontal ligament cells (hPDLCs). Carbon monoxide-releasing molecule-3 (CORM-3) is a water-soluble compound that can release carbon monoxide (CO) in a controllable manner. CORM-3 has been shown the anti-inflammatory effect in different cell lineages. Methods: We stimulated periodontal ligament cells with LPS and high glucose. The expression of inflammatory cytokine was detected by ELISA. RT-qPCR, Western blot and immunofluorescence were used to detect the expression of TLR2, TLR4, RAGE and the activation of NF-κB pathway. We performed silencing and overexpression treatment of RAGE targeting the role of RAGE. We performed the immunostaining of paraffin sections of the periodontitis model in diabetes rats. Results: The results showed that CORM-3 significantly inhibited the expression of inflammatory cytokine in hPDLCs stimulated with LPS and high glucose. CORM-3 also inhibited LPS and high glucose-induced expression of RAGE/NF-κB pathway and TLR2/TLR4/NF-κB pathway. Silence of RAGE resulted in significantly decreased expression of proteins above. Overexpression of RAGE significantly enhanced the expression of these factors. CORM-3 abrogated the effect of RAGE partially. In animal model, CORM-3 suppressed the inflammatory response of periodontal tissues in experimental periodontitis of diabetic rats. Discussion: Our research proved CORM-3 reduced the inflammatory response via RAGE/NF-κB pathway and TLR2/TLR4/NF-κB pathway in the process of high glucose exacerbated periodontitis. These findings demonstrated the role of RAGE in the process of high glucose exacerbated periodontitis and suggested that CORM3 be a potential therapeutic strategy for the treatment of diabetes patients with periodontitis. [ABSTRACT FROM AUTHOR]

Transcriptome analysis is important for interpreting the functional elements of the genome and revealing the molecular constituents of cells and tissues. Herein, differentially transcribed genes were identified by deep sequencing after zebrafish (Danio rerio) were exposed to β-diketone antibiotics (DKAs); 23,129 and 23,550 mapped genes were detected in control and treatment groups, a total of 3238 genes were differentially expressed between control and treatment groups. Of these genes, 328 genes (213 up- and 115 down-regulation) had significant differential expression (p < 0.05) and an expression ratio (control/treatment) of >2 or

Fluoroquinolones (FQs) and tetracyclines (TCs), the two β-diketone antibiotics (DKAs), are two frequently detected pollutants in the environment; however, little data are available on their combined toxicity to zebrafish (Danio rerio). This study reports that toxicologic effects of combined DKA (FQs-TCs) exposure on zebrafish were comparable with or slightly less than those of TCs alone, showing that TCs played a major toxicologic role in the mixtures. The effects of FQs, TCs, and DKAs on malformation rates of zebrafish were dose dependent, with EC50 values of 481.3, 16.4, and 135.1 mg/L, respectively. According to the combined effects of DKAs on zebrafish hatching, mortality, and malformation rates, the interaction between FQs and TCs was shown to be antagonistic based on three assessment methods: Toxic Unit, Additional Index, and Mixture Toxic Index. The 1.56 mg/L TC and 9.38 mg/L DKA treatments resulted in higher zebrafish basal swimming rate compared with the control group at 120 hours postfertilization (hpf). in both light and light-to-dark photoperiod experiments. Under conditions of no obvious abnormality in cardiac development, the heart beats were decreased significantly because of DKA exposure, such as decreasing by ∼20% at 150 mg/L DKAs. Transmission electron microscopy observation of myocytes from DKA-exposed hearts displayed prominent interruptions and myofibrillar disorganization of the normal parallel alignment of thick and thin filaments, and partial edematous and dissolved membranes of cell nuclear tissues. At 90 mg/L DKAs, the transcriptional levels of the acta1a, myl7, and gle1b genes, related to heart development and skeletal muscle formation, were significantly changed. This is consistent with the swimming behavior and histopathologic results obtained by transmission electron microscopy. In summary, the toxicity of the combined DKAs to zebrafish was comparable with or less than that of TCs alone and had the ability to impair individual behaviors that are of great importance in the assessment of their ecologic fitness. © 2014 Wiley Periodicals, Inc. Environ Toxicol 31: 736-750, 2016.

Herein, we developed a novel integrated apparatus to perform phase separation based on magnetic-stirring, salt-induced, liquid-liquid microextraction for determination of five fluoroquinolones in animal-based foods by HPLC analysis. The novel integrated apparatus consisted of three simple HDPE (high density polyethylene) parts that were used to separate the solvent from the aqueous solution prior to retrieving the extractant. The extraction parameters were optimized using the response surface method based on central composite design: 791 μL of acetone solvent, 2.5 g of Na2SO4, pH 1.7, 3.0 min of stir time, and 5.5 min centrifugation. The limits of detection were 0.07-0.53 μg kg(-1) and recoveries were 91.6-105.0% for the five fluoroquinolones from milk, eggs and honey. This method is easily constructed from inexpensive materials, extraction efficiency is high, and the approach is compatible with HPLC analysis. Thus, it has excellent prospects for sample pre-treatment and analysis of fluoroquinolones in animal-based foods.

The removal efficiency of Cu(2+) by Spirulina platensis (strain FACHB-834), in viable and heat-inactivated forms, was investigated in the presence and absence of linear alkylbenzene sulfonate (LAS). When the initial Cu(2+) concentration was in the range of 0.5-1.5 mg · L(-1) , a slight increase in growth rate of FACHB-834 was observed. In contrast, when Cu(2+) or LAS concentrations were at or higher than 2.0 or 6.0 mg · L(-1) , respectively, the growth of FACHB-834 was inhibited and displayed yellowing and fragmentation of filaments. The presence of LAS improved Cu(2+) removal by ~20%, and accelerated attainment of Cu(2+) retention equilibrium. For the 2- mg · L(-1) Cu(2+) treatments, retention equilibrium occurred within 2 d and showed maximum Cu(2+) removal of 1.83 mg · L(-1) . In the presence of LAS, the ratio of extracellular bound Cu(2+) to intracellular Cu(2+) taken up by the cells was lower (1.05-2.26) than corresponding ratios (2.46-7.85) in the absence of LAS. The percentages of extracellular bound Cu(2+) to total Cu(2+) removal (both bound and taken up by cells) in the presence of LAS ranged from 51.2% to 69.3%, which was lower than their corresponding percentages (71.1%-88.7%) in the absence of LAS. LAS promoted biologically active transport of the extracellular bound form of Cu(2+) into the cell. In contrast, the addition of LAS did not increase the maximum removal efficiency of Cu(2+) (61.4% ± 5.6%) by heat-inactivated cells compared to that of living cells (59.6% ± 6.0%). These results provide a theoretical foundation for designing bioremediation strategies using FACHB-834 for use in surface waters contaminated by both heavy metals and LAS.

β-Diketone antibiotics (DKAs) can produce chronic toxicity in aquatic ecosystems due to their pseudo-persistent in the environment. In this study, after long-term DKA exposure to zebrafish (Danio rerio), 47 protein spots had greater than 2-fold differential expression as compared to the control; there were 26 positive proteins with 14 up-regulated and 12 down-regulated. The main functions of the differentially expressed proteins were related to signal transduction mechanisms and the cytoskeleton. Of the 26 target genes, 11 genes were consistent between their transcriptional and translational levels. Low dose DKA exposure (4.69 and 9.38 mg/L) stimulated spontaneous movement in zebrafish. Changes in both creatine kinase activity and creatine concentration showed a similar trend to zebrafish activity. There was no obvious change in SV-BA after DKA exposure, while a reduction of heart rate was concomitant with increasing DKA concentrations. DKAs also induced severe histopathological changes in zebrafish heart tissue, such as dissolution of cristae and vacuolation of mitochondria. These results demonstrated that trace-level DKA exposure affects a variety of cellular and biological processes in zebrafish.

Mortality of gastric cancer is the second in cancer-associated deaths due to the lack of specific symptoms at an early stage, and thus, early detection of gastric cancer is receiving more attention. Nowadays, volatile organic compound (VOC) indicators have been found to be helpful for screening a variety of cancers. Meanwhile, hybrid VOC indicators, namely, VOCs derived from both human breath and body fluids, provide more information about health status. Nevertheless, details of VOCs in body fluid (e.g. saliva) are still unclear and tracking of these VOCs remains a challenge. In this research, 10 kinds of VOCs released from the saliva were reported to be potential indicators for gastric cancer prewarning. To track these potential indicators with high specificity, a surface-enhanced Raman scattering (SERS) sensor based on a thin layer of MIL-100 (Fe) shell-wrapped Au nanostars (Au-star) was developed, and part of the aforementioned VOC indicators (e.g., 2-butanone, eucalyptol, and isopropanol) were found to be selectively detected by the sensor. These pilot results indicate a bright future for the proposed strategy for disease screening and the design of future high-performance SERS sensors. [ABSTRACT FROM AUTHOR]

Visual obstacle avoidance is widely applied to unmanned aerial vehicles (UAVs) and mobile robot fields. A simple system architecture, low power consumption, optimized processing, and real‐time performance are extremely needed due to the limited payload of some mini UAVs. To address these issues, an obstacle avoidance system harnessing the rate encoding features of a photonic spiking neuron based on a Fabry–Pérot (FP) laser is proposed, which simulates the monocular vision. Here, time to collision is used to describe the distance of obstacles. The experimental results show that the FP laser excites ultra‐fast spike responses in real time for the following cases, facilitating the generation of control commands by motor neurons to realize accurate decision‐making. Four cases of mobile obstacle avoidance scenarios, including "Constant velocity approach", "Approach and retreat", "The motion state involving stays", and "Approach with different velocities", and obstacle avoidance problems with multiple stationary obstacles appearing simultaneously are experimentally analyzed. The system exhibits a spike response rate of up to 5 GHz. This work proves the feasibility of applying the ultra‐fast photonic obstacle avoidance system to UAVs and other fields in the future and highlights the potential of photonic neuromorphic processor platforms. [ABSTRACT FROM AUTHOR]

Here, we report a RhI3-catalyzed intramolecular carboamination reaction to access polysubstituted indoles. The protocol features a broad substrate scope (>20 examples), good functional-group compatibility, and a low catalyst loading (5 mol% Rh). Good to excellent yields (up to 98%) were obtained. An unprecedented C–N bond-cleavage mode via a six-membered transition state σ-bond metathesis mechanism was proposed based on control experiments. A series of C3-allylated indole derivatives were accessed, proving that the system provides an alternative catalytic route to polysubstituted indoles. [ABSTRACT FROM AUTHOR]