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I2-promoted synthesis of BIMPYs.

This report presents an analytical approach to the natural frequency analysis of a porous beam consisting of a host porous layer reinforced with graphene platelets (GPLs), namely GPL-reinforced porous core, and two piezoelectric outer layers. In the modelling, symmetric distributions of both porosity and GPLs in the core are supposed. The effective mechanical properties of the GPL-reinforced porous core are estimated by Halpin–Tsai model and the rule of mixture. The electric potential in each piezoelectric layer is assumed to vary linearly across its thickness. Two types of electrical boundary conditions, which are open- and closed-circuits, are considered for the free surfaces of the piezoelectric layers. Parabolic shear deformation beam theory associated with Hamilton’s principle is adopted to derive the governing equations of the free vibration. Afterwards these equations are solved analytically by Navier’s solution. Comparative and comprehensive studies are carried out to examine the accuracy and effects of parameters and conditions, such as GPL weight fraction, porosity coefficient, and electrical boundary conditions on the natural frequencies of the beam.

This paper presents static analysis and response of smart piezoelectric porous beams by mesh-free approach. The beam consists of a functionally graded porous core reinforced with graphene platelets (GPLs) and two piezoelectric face layers. The effective material properties of the core vary smoothly through the thickness direction, and they are estimated based upon Halpin–Tsai micromechanical model. The electric potential is assumed to vary linearly across the thickness of the piezoelectric layers. Polynomial basis function-based C1-Hermite interpolation for all displacement and electric potential variables of the problem is proposed for the mesh-free method to discretize the equilibrium equations. Parametric studies are carried out to investigate the effects of material parameters and boundary conditions on the deflection and stresses of the beam subjected to mechanical and/or electrical load(s). Furthermore, the study also highlights the piezoelectric effect on the static bending control of the proposed beam.

Aims: Synthesis of 1,4-Dihydropyridines (1,4-DHP) using heterogeneous catalyst under mild condition Objective: Our objective is to explore new applications of non-metal heterogeneous catalysts in the synthesis of 1,4-DHP derivatives in a greener and more efficient approach. Method: A greener and more efficient method for the synthesis of 1,4-DHPs and an asymmetric 1,4-DHP (Felodipine drug) was successfully developed in high yields using a heterogeneous SBA-15-SO3H catalyst. Result: A series of symmetric 1,4-DHP and an asymmetric 1,4-DHP (Felodipine drug) were successfully prepared in high yields using a heterogeneous SBA-15-SO3H catalyst. Conclusion: The catalyst, SBA-15-SO3H, exhibited an efficient catalyst activity for the synthesis of 1,4-DHP derivatives in high yields from the aldehyde, β-ketoester, and NH4OAc as a nitrogen source under mild conditions and short reaction time. Bronsted acid sites of this solid catalyst were figured out to play a key role in this transformation. Interestingly, our catalyst is air-stable and can be recycled at least 5 times without losing catalytic activity.

This paper aims to present thermo-electrical free vibration characteristics of functionally graded material (FGM) sandwich beam placed on the two-parameter elastic foundation. The beam is constructed of a foam core, two middle FGM layers, and two outer piezoelectric layers. It is assumed that the beam is subjected to a constant voltage and a uniform/linear temperature distribution. Physical properties of the core and two middle layers vary smoothly through the thickness according to the cosine and power-law forms, respectively. Lagrange equations in conjunction with the Reddy third-order beam theory is employed to derive the governing equations of motion. A simple polynomial trial function-based Ritz method is adopted for the approximation of the displacement field to obtain the vibration response. The correctness of the study is verified by comparisons with other authors’ published results. Influences of geometry parameters, material property distribution, applied voltage, elastic foundation, temperature distribution, temperature change, porosity coefficient, span-to-height ratio, and boundary conditions are investigated through parametric studies.

Quinoline derivatives are important moieties in bioactive molecules and advanced materials. However, an efficient strategy to synthesize quinoline derivatives remains challenging. Herein, we describe an efficient and practical method for the synthesis of quinolines by Cu-catalyzed cyclization of 2-amino benzyl alcohol with ketones (or secondary alcohols) via an acceptorless dehydrogenation pathway. Interestingly, a range of highly functionalized quinolines is prepared in good yields using low catalyst loading under relatively mild conditions. Furthermore, density functional theory (DFT) calculations are carried out to investigate mechanistic insights for the acceptorless dehydrogenation pathway.

Two efficient and practical approaches are reported for the synthesis of β- and δ-carbolines from 3,4-dibromopyridine. The synthesis is based on site-selective Cu-catalyzed double C–N coupling reactions and subsequent annulations by twofold Pd-catalyzed C–N coupling with amines.

An efficient Cu-catalyzed synthesis of carbazole derivatives is reported, which proceeds by double C–N coupling reactions of 2,2′-dibromobiphenyl and amines in the presence of air. The reaction is robust, proceeds in high yields, and tolerates a series of amines including neutral, electron-rich, electron-deficient aromatic amines and aliphatic amines.

A feeding trial was carried out to examine the effects of adding chestnut (Castanea sativa) polyphenols (CSP) on the growth, skin mucus and serum immune parameters of Nile tilapia (Oreochromis niloticus). Five experimental diets with inclusion levels of 0, 1, 2, 4, and 8 g kg−1 of CSP were fed to Nile tilapia fingerlings (12.77 ± 0.17 g fish−1) during an eight-week trial. Fish were analyzed on the fourth and eighth week to determine the influences of CSP on growth, skin mucus, and serum immune parameters. Challenging test versus Streptococcus agalactiae was evaluated at the end of the trial. Fish fed with CSP enriched diets displayed a significant increase (P ≤ 0.05) in growth and a decline in feed conversion ratio (P ≤ 0.05). Similarly, skin mucus and serum immune parameters were significantly increased (P ≤ 0.05) in fish fed CSP with respect to the control. The effects were already evident four weeks after the CSP administration. The disease protection test displayed that the fish's survival rate was significantly higher (P

A point interpolation meshfree method based on polynomial basic function is employed to analyze static behavior of sandwich beams with functionally graded face sheets and porous core whose mechanical properties vary continuously in the depth-direction. Transverse shear deformation is taken into account with the context of third-order beam theory which satisfies the vanishing of shear stress at the top and bottom surfaces. The equilibrium equations are derived from the principle of virtual work. Polynomial basic function is employed to construct shape functions and approximate the displacement field of computational domain. The accuracy of the computational method is confirmed by comparisons of computed results with those available in the literature. The convergence rate and effect of nodal distribution on the accuracy are examined in details. Numerical examples are performed to investigate the effects of span-to-height ratio, face sheet-core-face sheet thickness ratio, material volume fraction index, porosity coefficient, as well as different boundary conditions on transverse displacement, axial and shear stresses of the beams.

Doppler-guided transanal hemorrhoidal dearterialization (THD) was considered a less invasive and innovative method to treat hemorrhoidal disease, but it may impact the anal area during dearterialization and mucopexy. Thus, this study aimed to assess any changes in anorectal manometry of grade III and IV hemorrhoidal patients following THD treatment. This prospective observational study was conducted with patients who had grades III and IV hemorrhoidal disease. The patients were treated using THD at the Department of Surgery in the National Hospital of Traditional Medicine (Hanoi, Vietnam) between June 2012 and December 2013. Anorectal manometry was performed prior to THD and again between 6 and 12 months following the procedure. A total of 40 patients were enrolled in the study, including 32 with grade III hemorrhoids and 8 with grade IV hemorrhoids. The proportion of male patients (65%) was higher than that of female patients (35%), and the majority of patients (82.5%) were > 40 years old. The mean duration of symptoms prior to treatment was 12.3 years. The mean length of the anal sphincter was unchanged before and after THD (3.64 ± 0.40 cm prior to treatment vs. 3.66 ± 0.48 cm following treatment; p = 0.57). Significant differences in treatment-related changes were detected for all anorectal manometric measurements except maximum squeezing pressure (p

The methanol oxidation reaction (MOR) has recently gained a lot of attention due to its application in fuel cells and electrochemical sensors. To enhance the MOR, noble metal nanoparticles should be homogeneously dispersed on the electrode surface with the aid of one suitable support. In this work, 4-aminothiophenol (4-ATP) molecules which contain simultaneously amine and thiol groups were electro-grafted onto the electrode surface to provide anchoring sites, limit aggregation and ensure good dispersion of metal nanoparticles. The results showed a high density of platinum nanoparticles (PtNPs) with an average size of 25 nm on the glassy electrode modified with a 4-ATP supporting layer. Consequently, the MOR was improved by 2.1 times with the aid of the grafted 4-ATP layer. The electrochemical sensor based on PtNPs/4-ATP/GCE is able to detect MeOH in a linear range from 1.26 to 21.42 mM with a detection limit of 1.21 mM.

A series of 5-aryl-5H-pyrido[2',1':2,3]imidazo[4,5-b]indoles was successfully prepared in good yields by a practical four-step strategy. In this procedure, the key step was demonstrated to be the domino Pd-and Cu-catalyzed C–N coupling reactions of 3-bromo-2-(2-bromophenyl)imidazo[1,2-a]pyridine with amines.

We establish a relationship between the two important central lines of the triangle, the Euler line and the Brocard axis, in a configuration with an arbitrary rectangle and a random point. The classical Cartesian coordinate system method shows its strength in these theorems. Along with that, some related problems on rectangles and a random point are proposed with similar solutions using Cartesian coordinate system., Comment: 14 pages, 10 figures

Background The majority of infectious diseases of cultured fish is caused by bacteria. Rapid identification of bacterial pathogens is necessary for immediate management. The present study developed a custom Main Spectra Profile (MSP) database and validate the method using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) for rapid identification of fish bacterial pathogens. Streptococcus agalactiae, Streptococcus iniae, Aeromonas hydrophila, Aeromonas veronii, and Edwardsiella tarda obtained from diseased fish were used as representative bacterial pathogens in this study. Bacterial peptides were extracted to create a Main Spectra Profile (MSP), and the MSPs of each bacterial species was added into the MALDI Biotyper database. Fifteen additional isolates of each bacterial species were tested to validate the utilized technique. Results The MSPs of all field isolates were clearly distinguishable, and the MSPs of the same species were clustered together. The identification methodology was validated with 75 bacterial isolates. The reliability and specificity of the method were determined with MALDI Biotyper log score values and matching results with 16 s rDNA sequencing. The species identification using the public MALDI Biotyper library (Bruker MALDI Biotyper) showed unreliable results (log score 2.115, and a 100% matching result. Conclusion This study demonstrates an effective identification of fish bacterial pathogens when a complete custom-made MSP database is applied. Further applications require a broad, well-established database to accommodate prudent identification of many fish bacterial pathogens by MALDI-TOF MS.

• The Ga 1-x Mn x As/InGaAs layer exhibits a strong sensitivity to the magnetic field and temperature.

A highly efficient copper(II) catalyst system for alkylation of indoles with alcohols via hydrogen borrowing method has been developed to afford C3-alkylated indoles in good to excellent yields. Cu(OAc)2 in the combination with dppm ligand has been found to be the most suitable catalyst system for this alkylation reaction.

Bis(3-indolyl)methanes (BIM) are important and present in the structure of many alkaloid and bioactive compounds (anti-inflammatory, anticancer, antiobesity, antimicrobial, etc.). Herein, we have reported an air stable and convenient Cu(OAc)2 catalyst for alkylation of indoles with alcohols to give bis(3-indolyl)methanes in very good yields.

Around the world, the data assimilation framework has been reported to be of great interest for weather forecasting, oceanography modeling and for shallow water flows particularly for flood model. For flood model this method is a power full tool to identify time-independent parameters (e.g. Manning coefficients and initial conditions) and time-dependent parameters (e.g. inflow). This paper demonstrates the efficiency of the method to identify time-dependent parameter: inflow discharge with a real complex case Red River. Firstly, we briefly discuss about current methods for determining flow rate which encompasses the new technologies, then present the ability to recover flow rate of this method. For the case of very long time series, a temporal strategy with time overlapping is suggested to decrease the amount of memory required. In addition, some different aspects of data assimilation are covered from this case.

A highly selective and efficient method for the synthesis of 5-trifluoromethylated and 5-perfluoroalkylated pyrazoles has been developed which relies on the cyclization of hydrazine dianions with ethyl perfluorocarboxylates. The pyrazoles prepared were evaluated as potential inhibitors of alkaline phosphatases, namely human tissue non-specific alkaline phosphatase (h-TNAP) and tissue specific intestinal alkaline phosphatase (IAP). Most pyrazole derivatives inhibited h-IAP more markedly than h-TNAP and had minor effects on nucleotide pyrophosphatase/phosphodiesterases. Therefore, the compounds appear as potential selective inhibitors of h-IAP.

Two concise and efficient approaches were developed for the synthesis of α- and δ-carboline derivatives. The success of the synthesis relies on site-selective Suzuki-Miyaura reactions of 1-chloro-2-bromopyridine or 2,3-dibromopyridine with 2-bromophenylboronic acid and subsequent cyclization with amines which proceeds by twofold Pd-catalyzed C-N coupling reactions.

A miniaturised array of supercritical angle fluorescence (SAF) micro-optics embedded in a microfluidic chamber was fabricated by injection moulding. The fabricated chip could enhance the fluorescence signal around 46 times compared to a conventional microscope. Collection of the fluorescence signal from the SAF array is almost independent of the numerical aperture, and the limit of detection was improved 36-fold using a simple and inexpensive optical detection system.

Solid-phase PCR (SP-PCR) has become increasingly popular for molecular diagnosis and there have been a few attempts to incorporate SP-PCR into lab-on-a-chip (LOC) devices. However, their applicability for on-line diagnosis is hindered by the lack of sensitive and portable on-chip optical detection technology. In this paper, we addressed this challenge by combining the SP-PCR with super critical angle fluorescence (SAF) microlens array embedded in a microchip. We fabricated miniaturized SAF microlens array as part of a microfluidic chamber in thermoplastic material and performed multiplexed SP-PCR directly on top of the SAF microlens array. Attribute to the high fluorescence collection efficiency of the SAF microlens array, the SP-PCR assay on the LOC platform demonstrated a high sensitivity of 1.6 copies/µL, comparable to off-chip detection using conventional laser scanner. The combination of SP-PCR and SAF microlens array allows for on-chip highly sensitive and multiplexed pathogen detection with low-cost and compact optical components. The LOC platform would be widely used as a high-throughput biosensor to analyze food, clinical and environmental samples.

5,7-Dihydropyrido[3,2-b:5,6-b′]diindoles were prepared by a highly efficient two-step synthesis that involved a site-selective Suzuki coupling reaction of 2,3,5,6-tetrabromopyridine and a subsequent Pd-catalyzed cyclization that proceeded through a twofold C–N coupling reaction with aromatic and aliphatic amines. With the exception of the parent molecule, which was described in a patent without any characterization data, the 5,7-dihydropyrido[3,2-b:5,6-b′]diindoles are a new chemical entity. Their electrochemical and photochemical properties were investigated. These pyridodiindoles show promising fluorescence properties with good quantum yields and interesting electrochemical behavior. The optical and electronical properties were analyzed and explained by using DFT calculations.

In this article, a significant aspect of Brønsted groups in the preparation of HPA/Al-SBA-15 catalyst by immobilising heteropoly acid H3PW12O40 (HPA) to mesoporous Al-SBA-15 support was studied. The crucial factors affected the preparation such as functional groups formed on the support, the use of HPA type for the immobilisation (commercial catalyst or in-situ synthetic HPA), and Si/Al molar ratio of Al-SBA-15 were systematically investigated. The prepared catalysts were tested their performance in polar reagent reactions (fructone synthesis was chosen as an example) to show the effect of HPA after the immobilisaton. Here we tested the HPA content (by Energy-dispersive X-ray method), acidity (by temperature-programmed desorption of ammonia method) and the ethyl acetoacetate conversion in fructone synthesis to prove this concept. The other characterisation methods such as small angle x-ray scattering, Fourier-transform infrared spectroscopy, specific surface area and pore volume also showed the properties change of materials before and after HPA immobilisation. It was shown that the HPA/Al-SBA-15 sample prepared by using HPA commercial catalyst and NH4 + ion-exchanged Brønsted groups of mesoporous Al-SBA-15 support (Si/Al molar ratio of 15) showed the highest acidity and catalytic activity (ethyl acetoacetate conversion of 93.49 wt%) in comparison to HPA commercial catalyst as well as to the other catalysts. In addition, this catalyst also showed good catalytic stability after five reaction cycles with slightly reduction of activity, suggesting the prospect of employing HPA/Al-SBA-15 catalyst for organic synthesis of polar compounds.

Two efficient and practical approaches are reported for the synthesis of β- and γ-carboline derivatives from 3,4-dibromopyridine as a common starting material. The β-carbolines were prepared by site-selective Pd-catalyzed C–C coupling with o-bromophenylboronic acid and subsequent cyclization by double C–N coupling with amines. γ-Carbolines were prepared from the same starting material by C–N coupling with anilines and subsequent annulation by domino C–C/C–N coupling with o-bromophenylboronic acid.

The AMR (anisotropic magnetoresistance) and PHR (planar Hall resistance) contribution was analyzed for fabricated ring type sensor junctions in single and multiring bridge sensors, and their field sensitivity was examined. The voltage profile, i.e. the sum of AMR and PHR effects, reveal anti-symmetric behavior with the magnetic field with small offsets due to the self-balancing of ring arm resistances, but the voltage variations for the external field are additive for all junction components. The field sensitivity of the resistance for a single ring sensor is 9.5 m Ω / Oe , and its value monotonously increased to 102.6 m Ω / Oe for 17 rings with an enhanced active area.

In this study, we successfully synthesized monodisperse magnetite nanoparticles (NPs) (Fe3O4) by sonochemical method using mono (ethylene glycol) (MEG) as a modifier of the reaction environment and found that MEG could be a good candidate to prevent oxidation and toxicity in sonochemical synthesis. The microstructure and size distribution of the Fe3O4 NPs were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM) respectively. It revealed that the NPs prepared by MEG assisted sonochemical method show a smaller average size and better monodispersity compared to conventional sonochemical method. Due the the reduced average size and uniform size distribution nature of the NPs, it also showed good superparamagnetic properties with very low coercivity less than 0.5 Oe.

We have investigated a surfactant-assisted sonochemical approach to produce monodisperse Fe₃O₄ nanoparticles (NPs). The non-ionic surfactant Igepal CO-520 (Poly(oxyethylene)(5) nonylphenyl ether) has been used for the preparation of NPs and the effects on the NP size, size distribution, and magnetic properties have been studied. The Fe₃O₄ NPs were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and vibrating sample magnetometry (VSM). The results reveal that the NPs prepared by a Igepal CO-520-assisted sonochemical method exhibit a narrow range of size distributions and a high monodispersity compared to the NPs from the conventional sonochemical method. The analysis of NPs prepared in the presence of the surfactant suggested that it could be used not only as a protector to prevent the oxidation of Fe (Ⅱ), but also as a controller to vary the size of the NPs.

The planar Hall effect (PHE) sensor with a junction size of 3 μm × 3 μm for a single micro-bead detection has been fabricated successfully using a typical spin-valve thin film Ta(5)/NiFe(16)/Cu(1.2)/NiFe(2)/IrMn(15)/Ta(5) nm. The PHE sensor exhibits a sensitivity of about 7.2 μV Oe−1 in the magnetic field range of ±7 Oe approximately. We have performed an experiment to illustrated the possibility of single micro-bead detection by using a PHE sensor. A single micro-bead of 2.8 μm diameter size is secluded from 0.1% dilute solution of the Dynabeads® M-280 dropped on the sensor surface and is located on the sensor junction by using a micro magnetic needle. The comparison of the PHE voltage profiles in the field range from 0 to 20 Oe in the absence and presence of a single micro-bead identifies a single Dynabeads® M-280, the maximal signal change as large as ΔV ∼ 1.1 μV can be obtained at the field ∼6.6 Oe. The results are well described in terms of the reversal of a basic single domain structure.

We have investigated the planar Hall effect (PHE) in three multilayer structures such as a bilayer, a spin-valve and a weak exchange bias coupling bilayer structure introduced a very thin Cu spacer layer between the antiferromagnetic and ferromagnetic layers. These thin films are Ta(3)/NiFe(10)/IrMn(10)/Ta(3) (nm), Ta(3)/NiFe(10)/Cu(1.2)/NiFe(2)/IrMn(10)/Ta(3) (nm), and Ta(3)/NiFe(10)/Cu(0.2)/IrMn(10)/Ta(3) (nm), respectively. The active layers in all three structures were kept constant. The field-sensitivity of the fabricated PHE sensors obtained for the respected structures are about 1.6 muV middot Oe-1, 5 muV middot Oe-1, and 12 muV middot Oe-1, respectively. The results suggest that the sensor based on a weak exchange bias coupling structure has the highest field-sensitivity compared with the others. The proposed weak exchange bias coupling structure emphasizes for the development of the PHE sensor materials.

Planar Hall effect (PHE) sensors with the junction size of 50 mum times 50 mum were fabricated successfully by using spin-valve thin films Ta(5)/NiFe(x) /Cu(1.2)/NiFe(2)/IrMn(15)/Ta(5) (nm) with x = 4, 8, 10, 12, 16. The magnetic field sensitivity of the PHE sensors increases with increasing thickness of ferromagnetic (FM) free layer. The sensitivity of about 95.5 m Omega/(kA/m) can be obtained when the thickness of the FM-free layer increases up to 16 nm. The enhancement of sensitivity is explained by the shunt current from other layers. The PHE profiles are well described in terms of the Stoner-Wohlfarth energy model. The detection of magnetic micro-beads label Dynabeadsreg M-280 is demonstrated and the results revealed that the sensor is feasible for high-resolution biosensor applications.

This paper deals with the planar Hall effect (PHE) of Ta(5)/NiFe(tF)/Cu(1.2)/NiFe(tP)/IrMn(15)/Ta(5) (nm) spin-valve structures. Experimental investigations are performed for 50 mumtimes50 mum junctions with various thicknesses of free layer (tF = 4, 8, 10, 12, 16, 26 nm) and pinned layer (tP = 1, 2, 6, 8, 9, 12 nm). The results show that the thicker free layers, the higher PHE signal is observed. In addition, the thicker pinned layers lower PHE signal. The highest PHE sensitivity S of 196 muV/(kA/m) is obtained in the spin-valve configuration with tF = 26 nm and tP = 1 nm. The results are discussed in terms of the spin twist as well as to the coherent rotation of the magnetization in the individual ferromagnetic layers. This optimization is rather promising for the spintronic biochip developments.

Recently, planar Hall effect (PHE) has been widely pursued due to its application potential for biosensors. Planar Hall sensor is based on the anisotropy magnetoresistance and exhibits many advantages, such as large signal-to-noise ratio at low frequencies and high sensitivity at low applied field. The planar Hall resistance (PHR) curve in multilayer thin films with spinvalve structure has pre-eminent sensitivity when compared to single layer and bilayer thin films. In this work, we report a model for PHR calculation that includes the behaviour of single domain basic structure in the external magnetic field. Our results show a qualitative dependence between PHR curves and the angle (β) between the exchange biased field direction and the easy axis of the free layer. As the β increases the sensitivity of the PHR curves also increases. Further, it is shown that our calculation helps to determine the exchange biased field direction.

A highly selective and efficient method for the synthesis of 5-trifluoromethylated and 5-perfluoroalkylated pyrazoles has been developed which relies on the cyclization of hydrazine dianions with ethyl perfluorocarboxylates. The pyrazoles prepared were evaluated as potential inhibitors of alkaline phosphatases, namely human tissue non-specific alkaline phosphatase (h-TNAP) and tissue specific intestinal alkaline phosphatase (IAP). Most pyrazole derivatives inhibited h-IAP more markedly than h-TNAP and had minor effects on nucleotide pyrophosphatase/phosphodiesterases. Therefore, the compounds appear as potential selective inhibitors of h-IAP.

Two concise and efficient approaches were developed for the synthesis of α- and δ-carboline derivatives. The success of the synthesis relies on site-selective Suzuki–Miyaura reactions of 1-chloro-2-bromopyridine or 2,3-dibromopyridine with 2-bromophenylboronic acid and subsequent cyclization with amines which proceeds by twofold Pd-catalyzed C–N coupling reactions.

5,7-Dihydropyrido[3,2-b:5,6-b′]diindoles were prepared by a highly efficient two-step synthesis that involved a site-selective Suzuki coupling reaction of 2,3,5,6-tetrabromopyridine and a subsequent Pd-catalyzed cyclization that proceeded through a twofold C–N coupling reaction with aromatic and aliphatic amines. With the exception of the parent molecule, which was described in a patent without any characterization data, the 5,7-dihydropyrido[3,2-b:5,6-b′]diindoles are a new chemical entity. Their electrochemical and photochemical properties were investigated. These pyridodiindoles show promising fluorescence properties with good quantum yields and interesting electrochemical behavior. The optical and electronical properties were analyzed and explained by using DFT calculations.

A series of 5,10-dihydroindolo[3,2-b]indoles was successfully prepared by an efficient two-step strategy based on site-selective Pd-catalyzed cross-coupling reaction with N-methyl-2,3-dibromoindole and subsequent cyclization by two-fold Pd-catalyzed C–N coupling with amines. The products show a strong fluorescence.

Foodborne disease is a major public health threat worldwide. Salmonellosis, an infectious disease caused by Salmonella spp., is one of the most common foodborne diseases. Isolation and identification of Salmonella by conventional bacterial culture or molecular-based methods are time consuming andusually take a few hours to days to complete. In response to the demand for rapid on line or at site detection of pathogens, in this study, we describe for the first time an eight-chamber lab-on-a-chip (LOC) system with integrated magnetic beads-based sample preparation and loop-mediated isothermalamplification (LAMP) for rapid and quantitative detection of Salmonella spp. in food samples. The whole diagnostic procedures including DNA isolation, isothermal amplification, and real-time detection were accomplished in a single chamber. Up to eight samples could be handled simultaneously and the system was capable to detect Salmonella at concentration of 50 cells per test within 40 min. The simple design, together with high level of integration, isothermal amplification, and quantitative analysis of multiple samples in short time will greatly enhance the practical applicability of the LOC system for rapid on-site screening of Salmonella for applications in food safety control, environmental surveillance, and clinical diagnostics.

A series of indolo[2,3-b]quinoxaline derivatives were efficiently synthesized from 2,3-dibromoquinoxaline by two pathways. A one-pot approach using Pd-catalyzed two-fold C–N coupling and C–H activation reactions gave indolo[2,3-b]quinoxaline derivatives in good yields, but with limited substrate scope. In addition, a two-step approach to indolo[2,3-b]quinoxalines was developed which is based on Pd-catalyzed Suzuki coupling reactions and subsequent annulation by Pd-catalyzed two-fold C–N coupling with aromatic and aliphatic amines. The electrochemical and photochemical properties of indolo[2,3-b]quinoxaline derivatives were investigated. These studies show that 6-(4-methoxyphenyl)-6H-indolo[2,3-b]quinoxaline showed the highest HOMO energy level and lowest band gap.