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The Barbier reaction is generally regarded as a one-pot Grignard reaction. Here, the Grignard reaction of cinnamaldehyde is demonstrated to give a 1,2-addition product, while the Barbier reaction of cinnamaldehyde yields a macromolecule with interesting aggregation-induced emission type non-conjugated luminescence properties, which indicates that the Barbier reaction cannot be regarded as a one-pot Grignard reaction.

The Barbier reaction, a classical name reaction for carbon-carbon bond formation, has played important roles in organic chemistry for over 120 years. The introduction of the Barbier reaction into polymer chemistry for the development of a novel Barbier polymerization, expands the methodology, monomer, chemical structure and property libraries of polymerization, aggregation-induced emission (AIE) and non-traditional intrinsic luminescence (NTIL). This mini review focuses on Barbier polymerization, including the brief introduction of the history and importance of polymerization methods design and the achievements of Barbier polymerization from molecular design strategies, functionalities and properties. An outlook of Barbier polymerization is also proposed. This mini review on Barbier polymerization therefore may cause inspirations to scientists in different fields.

The developments of the living alkene polymerization method have achieved great progress and enabled the precise synthesis of important polyalkenes with controlled molecular weight, molecular weight distribution, and architecture through an anionic, cationic or radical strategy. However, it is still challenging to develop a living alkene polymerization method through an all-in-one strategy where anionic and radical characteristics are merged into one polymerization species. Here, a versatile living polymerization method is reported by introducing a well-established all-in-one covalent-anionic-radical Barbier strategy into a living polymerization. Through this living covalent-anionic-radical Barbier polymerization (Barbier CARP), narrow distributed polystyrenes, with

International audience; In this paper, the stability problem of a class of deterministic car-following systems with uniformly distributed delays is addressed with a particular focus on the effects induced by the delay parameters on the stability. To perform such an analysis, the frequency-sweeping approach introduced recently by the authors will be adopted. The corresponding results are easy to derive and to implement. As a byproduct of the analysis, the complete characterization of the delay intervals guaranteeing stability is explicitly derived. Two case studies with different network topology types (linear and ring configurations) are studied in detail. The stability problem of car-following systems under consideration is a specific consensus problem of multi-agent systems. Such examples allow illustrating the approach as well as the positive effect of using uniformly distributed delay in the modeling (compared with the commonly-used pointwise delay). The derived results show that the approach is effective and may be adopted to more general consensus problems for multi-agent systems.

International audience; The proportional-integral-derivative (PID) controller design for time-delay systems is a classical problem. We consider a general case where the three controller gains (k P , k I , and k D ) and the delay (τ) are all treated as free parameters. Our objective is to characterize the stability set in the parameter space of (k P ; k I ; k D ; τ). The problem is very involved due to the theoretical difficulties. In this paper, we introduce a MATLAB-based toolbox, called PID-Design-Delay toolbox. It is developed based on some recently-reported theoretical results, by which the problem can be systematically solved. The user is only required to input the necessary information via the graphical user interface (GUI) and then the stability analysis may be automatically fulfilled by the toolbox.

Non-small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) wild-type is intrinsic resistance to EGFR-tyrosine kinase inhibitors (TKIs). In this study, we assessed whether the combination of bisdemethoxycurcumin (BDMC) and icotinib could surmount primary EGFR-TKI resistance in NSCLC cells and investigated its molecular mechanism. Results showed that the combination of BDMC and icotinib produced potently synergistic growth inhibitory effect on primary EGFR-TKI-resistant NSCLC cell lines H460 (EGFR wild-type and K-ras mutation) and H1781 (EGFR wild-type and Her2 mutation). Compared with BDMC or icotinib alone, the two drug combination induced more significant apoptosis and autophagy via suppressing EGFR activity and interaction of Sp1 and HDCA1/HDCA2, which was accompanied by accumulation of reactive oxygen species (ROS), induction of DNA damage, and inhibition of cell migration and invasion. ROS inhibitor (NAC) and autophagy inhibitors (CQ or 3-MA) partially reversed BDMC plus icotinib-induced growth inhibitory effect on the NSCLC cells. Meanwhile, co-treatment with NAC attenuated the two drug combination-induced autophagy, apoptosis, DNA damage and decrease of cell migration and invasion ability. Also, 3-MA or CQ can abate the combination treatment-induced apoptosis and DNA damage, suggesting that there is crosstalk between different signaling pathways in the effect produced by the combination treatment. Our data indicate that BMDC has the potential to improve the treatment of primary EGFR-TKI resistant NISCLC that cannot be controlled with single-target agent, such as icotinib.

Cisplatin can cause a variety of DNA crosslink lesions including intra-strand and inter-strand crosslinks (ICLs), which are associated with the sensitivity of cancer cells to cisplatin. Here, we aimed to assess the contribution of the Fanconi anemia (FA), homologous recombination (HR) and nucleotide excision repair (NER) pathways to cisplatin resistance in non-small cell lung cancer (NSCLC)-derived cells. The expression of FA, HR and NER pathway-associated genes was assessed by RT-qPCR and Western blotting. siRNAs were used to knock down the expression of these genes. CCK-8 and flow cytometry assays were used to assess the viability and apoptotic rate of NSCLC-derived cells, respectively. Immunofluorescence and alkaline comet assays were used to assess the repair of ICLs. We found that acquired cisplatin-resistant NSCLC-derived A549/DR cells exhibited markedly enhanced FA and HR repair pathway capacities compared to its parental A549 cells and another independent NSCLC-derived cell line, Calu-1, which possesses a moderate innate resistance to cisplatin. siRNA-mediated silencing of the FA-associated genes FANCL and RAD18 and the HR-associated genes BRCA1 and BRCA2 significantly potentiated the sensitivity of A549/DR cells to cisplatin compared to A549 and Calu-1 cells, suggesting that the acquired cisplatin resistance in A549/DR cells may be attributed to enhanced FA and HR pathway capacities responsible for ICL repair. Although we found that expression knockdown of the NER-associated genes XPA and ERCC1 sensitized the three NSCLC-derived cell lines to cisplatin, the sensitization effect was more significant in Calu-1 cells than in A549 and A549/DR cells, implying that the innate cisplatin resistance in Calu-1 cells may result from an increased NER activity. Our results indicate that the functional status of DNA repair pathways determine the sensitivity of NSCLC cells to cisplatin. Direct targeting of the pathway that is involved in cisplatin resistance may be an effective strategy to surmount cisplatin resistance in NSCLC.

For the majority of patients with advanced non-small cell lung cancer (NSCLC), the standard of care remains platinum-based chemotherapy. However, cisplatin resistance is a big obstacle to the treatment, and elucidation of its mechanism is warranted. In this study, we showed that there was no difference in intracellular uptake of cisplatin or the removal of platinum-DNA adducts between a cisplatin-resistant NSCLC cell line (A549/DR) and a cisplatin-sensitive NSCLC cell line (A549). However, the capacity to repair DNA interstrand crosslinks (ICLs) and double-strand breaks (DSBs) was significantly enhanced in the A549/DR cell line compared to 3 cisplatin-sensitive cell lines. We found that the protein and mRNA expression levels of Pol η, a Y-family translesion synthesis (TLS) polymerase, were markedly increased upon cisplatin exposure in A549/DR cells compared with A549 cells. Furthermore, intracellular co-localization of Pol η and proliferation cell nuclear antigen (PCNA) induced by cisplatin or cisplatin plus gemcitabine treatment was inhibited by depleting ataxia telangiectasia mutated and Rad-3-related (ATR). Pol η depletion by siRNA sensitized A549/DR cells to cisplatin; co-depletion of Pol η and ATR further increased A549/DR cell death induced by cisplatin or cisplatin plus gemcitabine compared to depletion of Pol η or ATR alone, concomitant with inhibition of DNA ICL and DSB repair and accumulation of DNA damage. No additional sensitization effect of co-depleting Pol η and ATR was observed in A549 cells. These results demonstrate that co-inhibition of Pol η and ATR reverses the drug resistance of cisplatin-resistant NSCLC cells by blocking the repair of DNA ICLs and DSBs induced by cisplatin or cisplatin plus gemcitabine.

PET-Ti composites have already been preliminarily used in the medical area due to the benefit of moderate biocompatibility of PET and the excellent mechanical properties of Ti. The connection of these materials always utilizes various technologies. Comparing to other methods, laser joining has the ability to achieve a clean weld and heat up materials in a spatially localized area only the material parts to be welded. This article describes how pulse shape, peak power and pulse-width affect the welding quality. And, make a conclusion that pulsed laser shapes, no matter with ramped-down waveform or ramped-up waveform, can be used to minimize the degradation of PET causes the decrease of gas bubbles that influence the bond strength and width.

The phytic acid-coated titanium (IP6/Ti) electrode was prepared through a simple drop-drying process, with an aim of improving electrocatalytic activity toward the hydrogen evolution reaction (HER). Scanning electron microscope and X-ray photoelectron spectroscopy showed that the IP6 coated the substrate surface uniformly and completely. Evaluation of the electrode activity was carried out in 1.0 M NaOH by linear polarization, electrochemical impedance spectroscopy (EIS) and chronopotentiometry. The kinetic parameters obtained from Tafel curves reveal that the IP6 coating can enhance the exchange current density of the HER by 489 times compared to the bare Ti, and reduce the HER activation energy by nearly 50%. The EIS data prove that the charge transfer resistance of the HER was considerably reduced due to the IP6 coating, with a decrease in real surface area of the electrode. The catalytic effect of IP6 is due to an improvement in the charge transfer kinetics of the HER. This work indicates that IP6 may be a potent candidate as a catalyst for hydrogen energy production.

Measuring shape of bubbles is very important in many industrial processes, because that its behavior in the fluid is closely related to its morphology. Phase microscopy imaging (PMI) method is one of the best useful methods in this field. In the paper, considering on PMI idea, it is put out a new method which improves an ordinary light microscope into a dual function that can do both PMI and its ordinary microscopy function. Its optical structure is designed by using Mach-Zehnder interferometer method which can be added on the platform of ordinary microscope. A glass hole (bubble) is used as a sample to do phase microscopy imaging via the improved device. The results of the experiment and theory show that the phase distribution of bubble is closely related to the shape of it, which is very useful to detect the bubble’s behavior in the flow field. Besides bubbles, the improved microscope can be also used to observe the phase body such as cells.

With the development of DPM (digital phase microscopy) and FCM (flow cytometry), techniques of cell recognition are getting more and more applications in many fields. Researches on the information from cells are very important to these techniques. In this paper, focusing on the technique of analyzing light scattering information and its relation with the morphological structures of the leucocytes and erythrocytes have been done. Based on the VirtualLab simulation techniques, the light scattering images of amplitude, phase and polarization of these typical cells have been obtained. It is found that the amplitude, phase and polarization of these cells are closely related to their morphological structures by analyzing the images, which is very useful to identify biological cells.

Acquisition of data from both in situ spectroscopy detection and online chromatography-like separation is important for studying complex electrochemical reactions. The present work provides an example of combination of thin-layer spectral and electrophoretic electrochemistry, both based on thin-layer electrolysis. Two thin-layer electrochemical cells were used to investigate the electro-oxidation of solid ellagic acid at different potentials, in acidic, physiological, and alkaline buffer media. UV-vis spectra and cyclic voltabsorptograms of the oxidation products were recorded in situ without interference from the solid reactant. Four oxidation products, depending upon the buffer pH and the applied potential, were separated and detected by electrophoretic electrochemistry. The major products possess redox stability, possibly with a diquinonemethide structure. The minor product is considered as an o-quinone derivative with a lactone-ring-opening, which can be reduced or further oxidized at appropriate potentials. A consecutive-parallel reaction mechanism is proposed for the formation of four products of ellagic acid in different pH media, which enriches the knowledge about the oxidation pathway and antioxidant property of this biologically active polyphenol compound.

The increasing popularity of cloud service is leading people to concentrate more on cloud storage than traditional storage. However, cloud storage confronts many challenges, especially, the security of the out-sourced data (the data that is not stored/retrieved from the tenants own servers). Security not only can keep the data from attacking but also can recover the original data after attack efficiently. Thus, to address the security issue, we proposed a new distributed and data fragmentation model of cloud storage named DDFM (Distributed and Data Fragmentation Model). DDFM aims to provide tenants a secured and integrated cloud storage service with layer-to-layer protection strategy. The layer-to-layer protection strategy of our model includes three main algorithms: the Authentication and Authorization Management Algorithm based on OpenID and OAuth, the Data Fragment Algorithm based on Granular Computing and the Haystack File Storage Algorithm. Considering tenants' security requirement our model DDFM based on these algorithms provided a better decision of cloud storage architecture for our tenants. Furthermore, DDFM can defense most of the network threats and provide a secured way for the third-party applications to access sensitive information that stored on the cloud storage.