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A variety of linear and side-chained p-nitrostilbene derivatives with various numbers of bromine atoms were prepared to survey the crystal structural properties, the photoluminescence, and heavy atom effect on the singlet oxygen generation by two-photo absorption (TPA). Single crystals of 4-nitro-4′-(4″-bromo-phenyl-methyl-oxy)-diphenylethylene (C2), 4-nitro-4′-(3″,5″-dibromo-phenyl-methyl-oxy)-diphenylethylene (C3), 4-nitro-4′-(2′,3″,4′,5″,6″-pentabromo-phenyl-methyl-oxy)-diphenylethylene (C4) were obtained, and the structural characteristics were analyzed by X-ray diffraction. One- and two-photon optical properties of the photosensitizers are shown dependence on the numbers of substituted bromine atoms. While TPA cross-sections of the photosensitizers are diminished more considerably, singlet oxygen quantum yields of the photosensitizers are enhanced at some extents by the substituted bromine atoms. Side-chained photosensitizers display correspondingly higher singlet oxygen quantum yields and larger TPA cross-sections than the molecules with single bromine-substituted aromatic segment. Molecular modeling was also performed to reveal the fundamental reasons of the experimental observation. Photooxidation reaction of singlet oxygen with some substrates was employed to confirm singlet oxygen generation under one- and two-photon irradiation. more...

A linear programming phase unwrapping method in dual-wavelength digital holography is proposed and verified experimentally. The proposed method uses the square of height difference as a convergence standard and theoretically gives the boundary condition in a searching process. A simulation was performed by unwrapping step structures at different levels of Gaussian noise. As a result, our method is capable of recovering the discontinuities accurately. It is robust and straightforward. In the experiment, a microelectromechanical systems sample and a cylindrical lens were measured separately. The testing results were in good agreement with true values. Moreover, the proposed method is applicable not only in digital holography but also in other dual-wavelength interferometric techniques. more...

Brusatol is a natural quassinoid that shows a potential therapeutic use in cancer models by the inhibition of Nuclear factor erythroid 2-related factor 2 (Nrf2) and is capable of inducing a variety of biological effects. The effects of Brusatol on oocyte meiosis has not been addressed. In this study, we investigated the impact of Brusatol treatment on mouse oocyte maturation and its possible mechanism. Our data demonstrated that Brusatol treatment disrupted oocyte maturation and spindle/chromosome organization by modulating Nrf2-Cyclin B1 pathway, as the influence of Brusatol was compensated by the addition of Nrf2 activation plasmid, and the mRNA and protein levels of Cyclin B1 were severely reduced in oocytes following Nrf2 decline. In summary, our data support a model that Brusatol, through the inhibition of Nrf2, modulate Cyclin B1 levels, consequently disturbing proper spindle assembly and chromosome condensation in meiotic oocytes. more...

Nowadays, stator current analysis used for detecting the incipient fault in squirrel cage motor has received much attention. However, in the case of interturn short circuit in stator, the traditional symmetrical component method has lost the precondition due to the harmonics and noise; the negative sequence component (NSC) is hard to be obtained accurately. For broken rotor bars, the new added fault feature blanked by fundamental component is also difficult to be discriminated in the current spectrum. To solve the above problems, a fundamental component extraction (FCE) method is proposed in this paper. On one hand, via the antisynchronous speed coordinate (ASC) transformation, NSC of extracted signals is transformed into the DC value. The amplitude of synthetic vector of NSC is used to evaluate the severity of stator fault. On the other hand, the extracted fundamental component can be filtered out to make the rotor fault feature emerge from the stator current spectrum. Experiment results indicate that this method is feasible and effective in both interturn short circuit and broken rotor bars fault diagnosis. Furthermore, only stator currents and voltage frequency are needed to be recorded, and this method is easy to implement. more...

The vibration signal of the motor bearing has strong nonstationary and nonlinear characteristics, and it is arduous to accurately recognize the degradation state of the motor bearing with traditional single time or frequency domain indexes. A hybrid domain feature extraction method based on distance evaluation technique (DET) is proposed to solve this problem. Firstly, the vibration signal of the motor bearing is decomposed by ensemble empirical mode decomposition (EEMD). The proper intrinsic mode function (IMF) component that is the most sensitive to the degradation of the motor bearing is selected according to the sensitive IMF selection algorithm based on the similarity evaluation. Then the distance evaluation factor of each characteristic parameter is calculated by the DET method. The differential method is used to extract sensitive characteristic parameters which compose the characteristic matrix. And then the extracted degradation characteristic matrix is used as the input of support vector machine (SVM) to identify the degradation state. Finally, It is demonstrated that the proposed hybrid domain feature extraction method has higher recognition accuracy and shorter recognition time by comparative analysis. The positive performance of the method is verified. more...

We conducted a meta-analysis to investigate the controversial association of CD147 expression with HCC prognosis and clinicopathological characteristics. Eight studies from PubMed (1966–2016), EMBASE (1980–2016), Cochrane Library (1996–2016), Web of Science (1945–2016), China National Knowledge Infrastructure (1982–2016), and Wanfang databases (1988–2016) were considered. The associations between CD147 expression and clinicopathological parameters and overall survival (OS) or DFS/RFS were reassessed using the meta-analysis for odds ratio (OR) or hazard ratio (HR) and 95% confidence interval (CI). CD147 expression was associated with DFS/RFS (HR = 3.26; 95% CI: 1.82–5.83; P<0.0001) but not with OS (HR = 1.35; 95% CI: 0.56–3.29; P=0.51). We also delved deeper into the association between median survival time and CD147 expression owing to significant heterogeneity and found significant differences between high and low CD147 expression groups with respect to median survival time. CD147 expression was closely associated with the TNM stage (OR = 0.18; 95% CI: 0.04–0.85; P=0.03) and venous invasion (OR = 6.29; 95% CI: 1.70–23.20; P=0.006). In contrast, there was no association between CD147 expression and tumor stage, cirrhosis, differentiation, lymph node metastasis, HBsAg, and serum AFP levels. Thus, CD147 expression is potentially closely related to HCC survival and associated clinicopathological parameters, paving the way for further research. more...

Based on a novel Mach–Zehnder point diffraction interferometer, a real-time method to determinate beam propagation factor M 2 of laser beams is presented. By using the proposed point diffraction interferometer, the intensity profile and wavefront of laser beam are completely extracted from a single interferogram in one-shot measurement. Knowing the complex field of laser beam yields the beam's propagation parameters such as beam propagation factor M 2 conform to the ISO standard method. The experimental method is simple, fast and operates without movable parts, which is allowed to investigate laser beams in conditions inaccessible using the existing method. more...

The solubilities of some polycyclic aromatic hydrocarbons (PAHs) in supercritical fluids were correlated and predicted using the compressed gas model and the reference solubilities. By introducing the reference solubilities, the compressed gas models combined with Peng–Robinson equation of state, Carnahan–Starling–van der Waals hard sphere equation of state and van der Waals one-parameter mixing rules can yield the overall averages of the average absolute relative deviations (AARDs) of 7.45% and 8.16% in solubility correlation for PAHs in supercritical fluids, respectively, which are much less than the values obtained using the compressed gas model combined with the corresponding equation of state and the sublimation pressures of the solutes. By introducing the reference solubilities, the calculated solubilities are not sensitive to the binary interaction parameters and the solubilities of PAHs in the corresponding supercritical fluid can be predicted with a specific binary interaction parameter. When using reference solubilities in the compressed gas model, the two equations of state provide comparable average AARDs in solubility prediction for PAHs in supercritical fluids, which are 14.00% and 14.19%, respectively. The introduction of reference solubilities into the compressed gas model provides a feasible and simple solubility prediction method for the compounds in supercritical fluids without using their sublimation pressures. Moreover, combined with the reference solubilities and the compressed gas model, the hard sphere equation of state provides a more simple method to predict the solubilities of solutes in supercritical fluids with only their solid molar volumes. more...

Laser Rapid Prototyping (LRP) can make the material accumulating by layer. And during the process, it has been known that shrinking stress may cause curl distortion. We have attempted to improve the processing speed and reduce the frequency of ON/OFF the laser. In this paper, we propose a new trajectory scan algorithm based on square lattice for Laser Rapid Prototyping (LRP). First, side-length of the square lattice is determined by the metal type and the material properties, and a set of regular square lattices is arranged based on the slices. Then, following the principles of not repeating and fewer breakpoints in solving Traveling Salesman Problem (TSP), the scanning sequence for each area is calculated. Therefore, a certain scan strategy can be determined, followed by the output of trajectory scan. We present the specific steps of the algorithm. The experiment proves the feasibility and superiority of the algorithm. more...

The purpose of this work is to promote an improvement of backbone networks in terms of availability and remote access. It especially focuses on network environments based on a hub and spoke topology. The significant findings indicate that data isolation, data encryption and encrypted dynamic routing information transmission are the main requirements for backbone network security. In addition, due to the importance of the backbone network, redundancy is also a necessary consideration for its availability, especially link and gateway redundancies. This report introduces a two-surface structure based on particular security protocols addressing backbone network security. The simulation of the proposed structure was carried out on GNS3, but a performance test on real devices is still needed for further research. more...

Background The p6 region of the HIV-1 structural precursor polyprotein, Gag, contains two motifs, P7TAP11 and L35YPLXSL41, designated as late (L) domain-1 and -2, respectively. These motifs bind the ESCRT-I factor Tsg101 and the ESCRT adaptor Alix, respectively, and are critical for efficient budding of virus particles from the plasma membrane. L domain-2 is thought to be functionally redundant to PTAP. To identify possible other functions of L domain-2, we examined this motif in dominant viruses that emerged in a group of 14 women who had detectable levels of HIV-1 in both plasma and genital tract despite a history of current or previous antiretroviral therapy. Results Remarkably, variants possessing mutations or rare polymorphisms in the highly conserved L domain-2 were identified in seven of these women. A mutation in a conserved residue (S40A) that does not reduce Gag interaction with Alix and therefore did not reduce budding efficiency was further investigated. This mutation causes a simultaneous change in the Pol reading frame but exhibits little deficiency in Gag processing and virion maturation. Whether introduced into the HIV-1 NL4-3 strain genome or a model protease (PR) precursor, S40A reduced production of mature PR. This same mutation also led to high level detection of two extended forms of PR that were fairly stable compared to the WT in the presence of IDV at various concentrations; one of the extended forms was effective in trans processing even at micromolar IDV. Conclusions Our results indicate that L domain-2, considered redundant in vitro, can undergo mutations in vivo that significantly alter PR function. These may contribute fitness benefits in both the absence and presence of PR inhibitor. Electronic supplementary material The online version of this article (doi:10.1186/s12977-016-0298-1) contains supplementary material, which is available to authorized users. more...

Acinetobacter baumannii has been becoming a great challenge to clinicians due to their resistance to almost all available antibiotics. In this study, we sequenced the genome from a multiple antibiotics resistant Acinetobacter baumannii stain which was named A. baumannii-1isolated from China by SMRT sequencing technology to explore its potential mechanisms to antibiotic resistance. We found that several mechanisms might contribute to the antibiotic resistance of Acinetobacter baumannii. Specifically, we found that SNP in genes associated with nucleotide excision repair and ABC transporter might contribute to its resistance to multiple antibiotics; we also found that specific genes associated with bacterial DNA integration and recombination, DNA-mediated transposition and response to antibiotics might contribute to its resistance to multiple antibiotics; Furthermore, specific genes associated with penicillin and cephalosporin biosynthetic pathway and specific genes associated with CHDL and MBL β-lactamase genes might contribute to its resistance to multiple antibiotics. Thus, the detailed mechanisms by which Acinetobacter baumannii show extensive resistance to multiple antibiotics are very complicated. Such a study might be helpful to develop new strategies to control Acinetobacter baumannii infection. more...

Prognostic is a key step of the condition-based maintenance (CBM). In order to improve the predicting performance, a novel method for prognostic for the hydraulic pump is proposed in this paper. Based on the improvement of the traditional composite spectrum, the DCT-composite spectrum (DCS) fusion algorithm is initially presented to make fusion of multi-channel vibration signals. The DCS composite spectrum entropy is extracted as the feature. Furthermore, the modified echo state networks (ESN) model is established for prognostic using the extracted feature. The reservoir is updated and the elements of the neighboring matrix are redefined for improving predicting accuracy. Analysis of the application in the hydraulic pump degradation experiment demonstrates that the proposed algorithm is feasible and is meaningful for CBM. more...

In this paper, the solubilities of some solid n -alkanes in supercritical carbon dioxide were correlated and predicted using the Carnahan–Starling–van der Waals model with a density-dependent parameter of a 12 . It was found that the parameter values of a 12 for solid n -alkanes in CO 2 at different temperatures are equal at the crossover pressure of 24 MPa, and a 12 can be correlated with carbon number of the corresponding solid n -alkanes. At a given temperature, the linear fit of parameters a 12 versus the density of the solvent was used for solubility correlation, resulting in an average absolute average relative deviation of 11.82%, which is comparable with that of the Peng–Robinson equation of state combined with the van der Waals two-parameter mixing rule model. The regressed slope m and intercept n of the linear fit can also be correlated with the carbon number of solid n -alkanes. The solubilities of solid n -alkanes can be predicted with a 12 at the crossover pressure and slope m or with intercept n and slope m . more...

This paper presents experimental and theoretical investigations into excited-state intramolecular proton transfer (ESIPT) in new chromophores with hydroxyl and imino groups under one- and two-photon excitation. The results show that internal hydrogen bonding exhibits a remarkable influence on the maximum absorption wavelength of 2-[(4'-N,N-diethylaminodiphenylethylene-4-ylimino)methyl]phenol (C1) and 2-[(4'-methoxyl-diphenylethylene-4-ylimino)methyl]phenol (C3). Compounds C1 and C3 exhibit well-separated dual fluorescence emission bands under one- and two-photon excitation. The second fluorescence peaks of C1 and C3 are characterized by much larger Stokes shift than the first normal peaks (ca. 140 vs. 30 nm). 4-[(4'-N,N-Diethylaminodiphenylethylene-4-ylimino)methyl]phenol (C2) and 4-[(4'-methoxyldiphenylethylene-4-ylimino)methyl]phenol (C4) display single emission bands with small Stokes shifts (ca. 30 nm) in various solvents under one- and two-photon excitation. Furthermore, the first emission maxima of C1 and C3 are almost identical to the maximum fluorescence emission wavelengths of C2 and C4, respectively. These results show that C1 and C3 can undergo ESIPT via a reasonable six-membered ring, while there is no ESIPT in C2 and C4 under one- and two-photon excitation. Compounds C1 and C2 have larger two-photon absorption cross-sections under various near-infrared laser frequencies tuned from 700 to 880 nm. Molecular geometry optimization of the phototautomers (enol and keto) was performed to analyze the experimental results. The possibility of using these chromophores for metal ions as chemosensors of was thoroughly investigated. In DMF C3 exhibits excellent sensing responses to Zn(2+) and Fe(3+) ions through a greatly increased greatly and a largely reduced emission, respectively. In methanol disappearance of ESIPT emission with added Zn(2+) ions confirms its existence. The binding constants of C3 with Zn(2+) and Fe(3+) ions in DMF are also estimated. more...

Background and objective It has been proven that the insulin-like growth factor 1 receptor (IGF-1R) gene is an important regulator of many aspects of growth, differentiation, and development. The insulin-like growth factor 2 receptor (IGF-2R) gene is a negative mediator for carcinogenesis. The aim of this study is to investigate the relationship of IGF-1R+1013(G/A) and IGF-2R+1619(G/A) single nucleotide polymorphism (SNP) with platinum-based chemotherapy outcomes in advanced non-small cell lung cancer (NSCLC). Methods A total of 132 patients with NSCLC were routinely treated with platinum-based chemotherapy, and their clinical responses were evaluated after four cycles of chemotherapy. IGF-1R+1013(G/A) and IGF-2R+1619(G/A) were genotyped using polymerase chain reaction-restrictive fragment length polymorphism. The relationship between IGF-1R+1013(G/A) and IGF-2R+1619(G/A) genotypes and the clinical benefit rate, as well as the median survival time (MST), was analyzed. Results No significant association was found between IGF-1R+1013(G/A) and IGF-2R+1619(G/A) polymorphisms with clinical benefit (P>0.05). Further, we found that the two SNPs could not work together (P=0.975). The MST of patients with IGF-1R+1013(G/A) genotypes with A allele (GA+AA) was significantly shorter than that of GG genotype carriers (P=0.017). There was no significant difference in MST in patients with IGF-2R+1619(G/A) A allele (GA+AA) carrier and GG genotype carrier (P=0.575). The two SNPs showed a synergistic effect on MST. Patients who carried a mutant allele A of IGF-1R+1013(G/A) and a mutant allele A of IGF-2R+1619(G/A) had a MST of 12 months, which was significantly shorter than that of patients with other genotypes (P more...

The acquisition of multidrug resistance in nosocomial pathogens such as Serratia marcescens has been reported in the absence of antibiotic selection pressure. The broad antimicrobial spectrum of aminoglycosides and their synergistic antimicrobial effect in association with other drugs (such as β-lactams and fluoroquinolones) suggest the possible use of these antibiotics as a therapy for life-threatening infections. One of the most important mechanisms of aminoglycoside resistance is posttranscriptional methylation of 16S rRNA conferred by methyltransferases. To date, 10 kinds of 16S rRNA methyltransferase genes (armA, rmtA, rmtB, rmtC, rmtD, rmtE, rmtF, rmtG, rmtH, and npmA), whose products confer high-level resistance to aminoglycosides, have been reported in various Enterobacteriaceae strains [1]. The rmtB gene was first identified in S. marcescens in Japan, but has not been reported in S. marcescens elsewhere [2]. In the present study, we described an isolate of S. marcescens harboring rmtB, together with quinolone resistance genes and various β-lactamase genes, for the first time in China. A strain of S. marcescens, designated GN1384, was isolated from the urine of a 81-yr-old male patient who suffered from urinary tract infections in September 2009 and was admitted to the second hospital of Hefei, China. Species identification was performed with the Vitek2 system (bioMerieux, Marcy l'Etoile, France) and confirmed with API 20E (bioMerieux). The minimum inhibitory concentrations (MICs) of various antibiotics were determined by using the agar dilution method, and susceptibility data were interpreted by using the Clinical and Laboratory Standards Institute guidelines [3]. The isolate showed a multiple drug resistant pattern, including some β-lactams, all the aminoglycosides, and fluoroquinolones (Table 1). Table 1 Characteristics of clinical isolate S. marcescens GN1384 and its transconjugant Then, genomic and plasmid DNA of strain GN1384 was extracted. Using primers described previously, we identified the resistance genotype of this strain by detecting the following resistance determinants through PCR, based on the above resistance phenotypes: 16S rRNA methyltransferase genes (armA, rmtA, rmtB, rmtC, rmtD, rmtE, and npmA); plasmid-mediated quinolone resistance determinants (qnrA, qnrB, qnrS, qnrC, qnrD, aac (6')-Ib-cr, and qepA); chromosome mutations associated with fluoroquinolone resistance (gyrA, parC, and parE); and genes coding for β-lactamases (TEM, CTX-M, SHV, OXA-1) [4,5,6,7]. The positive amplicons were subsequently sequenced, and the results indicated the presence of rmtB, aac(6')-Ib-cr, blaCTX-M-14, blaTEM-1, and blaOXA-1. In addition, two amino acid changes (Ser83Leu and Asp87Asn) in GyrA and five amino acid changes (Thr57Ser, Ser80Ile, Ala129Ser, Val131Leu, and Gly134Ser) in ParC were observed. Conjugation experiments were performed with Escherichia coli J53 as the recipient, as previously described [8]. The transconjugants were selected on agar plates containing sodium azide (100 mg/L) supplemented with amikacin (128 mg/L). Conjugation experiments showed that aac(6')-Ib-cr, blaTEM-1, blaCTX-M-14, and blaOXA-1 were cotransferred with rmtB to the recipient. The MIC results revealed that it simultaneously exhibited an elevated level of resistance to β-lactams, aminoglycosides, and fluoroquinolones (Table 1). The extremely high MICs of all aminoglycosides tested against the multidrug-resistant S. marcescens were likely due to the presence of the rmtB gene. In contrast to the rmtB plasmid isolated by Doi et al. [2], the plasmid bearing rmtB in our study was self-transferable, as observed by Bogaerts et al. [9]. In accordance with a previous study, the close linkage between 16S rRNA methyltransferase and β-lactamase as well as plasmid-mediated quinolone resistance determinants revealed the significant relationship of these genes amongst Enterobacteriaceae [10]. It was also observed that the plasmid-mediated quinolone resistance gene together with the mutations in gyrA and parC contributed to the high-level quinolone resistance in S. marcescens GN1384. Further studies are required to assess the genetic environment of these genes and the role of these new substitutions in resistance to fluoroquinolones. The continuous and widespread use of aminoglycosides, fluoroquinolones, and β-lactams in human or animal infection is the major driving force leading to these sophisticated resistance gene linkages. The dissemination of these linked genes by horizontal transfer simultaneously is very worrisome, and continuous monitoring should be reinforced. more...

The outbreak of carbapenem-resistant Klebsiella pneumoniae is a serious public health problem, especially in the neonatal intensive care unit (NICU).Fifteen K. pneumoniae strains were isolated from 7 neonates during June 3 to 28, 2017 in an NICU. Antimicrobial susceptibility was determined by the Vitek 2 system and microbroth dilution method. Multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE) were used to analyze the genetic relatedness of the isolates. Whole-genome sequencing and gene function analysis were performed to investigate pathogenicity and drug resistance and screen genomic islands.Three clones of K. pneumoniae were identified from 7 neonates: 7 strains of ST37, 7 of novel ST3006, and 1 of ST1224. Gene sequencing showed that the kpn1343 (ST37) strain harbored 12 resistance genes (OXA-33, TEM-1, SHV-11, AAC (6')-IId, AAC (3)-IIa, AAC (6')-Ib-cr, catB3, arr-3, sul1, oqxB, oqxA, CRP, and catB3) and included 15 genomic islands and 205 reduced virulence genes. The kpn1344 (ST3006) strain harbored 4 antibiotic-resistant genes (TEM-1, CTX-M-3, vgaC, and CRP) and included 19 genomic islands and 209 reduced virulence genes. MLST and PFGE showed that 15 strains of K. pneumoniae were divided into 3 groups with a high level of homology. ST1224 (kpn1362) was isolated on June 28, 2017, which was 10 days after the last isolate (kpn1359, June 18, 2017); thus, we speculated that ST1224 was not the clone that caused the outbreak.This co-outbreak of K. pneumoniae involved 2 clones: ST37 and ST3006. ST37 carried the multidrug-resistant genes, such as OXA-33, TEM-1, and SHV-11, and ST3006 was a novel K. pneumoniae ST typing. Whole-genome sequencing may be an effective method for screening bacterial-resistant genes and their functions. more...

This study presents a multiobjective energy management to optimize the renewable microgrid operation while satisfying a demand response and various operation constraints. With regard to energy cost minimization, pollutant emission reduction for better utilization of the renewable energy resources, such as wind and solar, as a competitive objective is proposed. Moreover, for maximizing the renewable microgrid operators, demand response benefits satisfying the load demand constraints amongst other operation constraints are incorporated into the operations of the renewable microgrid. The overall problem is formulated as a mixed-integer nonlinear constraint multiobjective optimization problem with different equality and inequality constraints. In this paper, an improved decomposition based multiobjective evolutionary algorithm is presented for optimal operation of the renewable microgrid with renewable energy sources and various devices such as diesel generators, micro-turbines, fuel cells, and battery energy storage. To improve the optimization process, differential evolution (DE) and the niche guided mating selection strategy are incorporated. Meanwhile, decomposition-based multiobjective evolutionary algorithm-DE is extended to tackle the constrained optimization problem. Finally, the proposed algorithm is applied in a renewable microgrid, and its superior performance is compared with the conventional evolutionary algorithms such as the multiobjective genetic algorithm and the original decomposition based multiobjective evolutionary algorithm.This study presents a multiobjective energy management to optimize the renewable microgrid operation while satisfying a demand response and various operation constraints. With regard to energy cost minimization, pollutant emission reduction for better utilization of the renewable energy resources, such as wind and solar, as a competitive objective is proposed. Moreover, for maximizing the renewable microgrid operators, demand response benefits satisfying the load demand constraints amongst other operation constraints are incorporated into the operations of the renewable microgrid. The overall problem is formulated as a mixed-integer nonlinear constraint multiobjective optimization problem with different equality and inequality constraints. In this paper, an improved decomposition based multiobjective evolutionary algorithm is presented for optimal operation of the renewable microgrid with renewable energy sources and various devices such as diesel generators, micro-turbines, fuel cells, and battery energy... more...

This paper presents a range of novel new branched conjugated dyes containing benzophenone moiety. As compared with those of 4-(p-benzoyl-styrene)yl-4'-(styrene)yl-triphenylamine (C1) and 4-(p-benzoyl-styrene)yl-4'-3,4,5-trimethoxyl-styrene)yl-triphenylamine (C2), the maximal linear absorption and emission wavelength of 4-(p-benzoyl-styrene)yl-4'-(p'-nitro-styrene)yl-triphenylamine (C3) displays red-shifted remarkably, While the fluorescence quantum yields of C3 are lower than those of C1 and C2 in various solvents. The fluorescence lifetimes of the derivatives were measured, and radiative and non-radiative transition constants of the derivatives were calculated. Two-photon absorption (TPA) optical data of the derivatives were measured by Ti:sapphire femtosecond laser tuning from 720 to 880 nm at intervals of 20 nm. TPA induced fluorescence emission of C3 is red-shifted with respected to that of C1 and C2. TPA cross sections of C3 are larger than those of C1 and C2 in various excited laser frequencies. TPA cross section of C2 and C3 are much larger than those of 3,4,5-(trimethoxylstyrene)yl-triphenylamine (C4) and 4-(p-nitrostyrene)yl-triphenylamine (C5) respectively under various near-IR Ti:sapphire femtosecond laser wavelength. C1 and C2 show similar one- and two- photon optical nature. Geometry optimization with ab initio method confirms that C3 has different electron density distribution, the energy levels in frontier orbitals, the dipole moment changes, the absorption and emission spectroscopy from those of C1 and C2. The cyclic voltammograms of the derivatives were detected in methylene chloride at various scan rates, and the energy of frontier orbials were estimated further from the redox potentials. more...

In this paper, we described the synthesis and characterization of new diphenylethylene bearing imino group. We concentrated particularly on the investigation of the possibility of the excited state intramolecular charge transfer (ESIPT) of the new dyes experimentally and theoretically. The absorption and fluorescence spectroscopy of the dyes were determined in various solvents. The results showed that the maximal absorption wavelength of 2-[(4′-N,N-dimethylamino-diphenylethylene-4-ylimino)methyl]phenol (C1) and 4-[(4′-N,N-dimethylamino-diphenylethylene-4-ylimino)methyl]phenol (C2) exhibited almost independence on the solvent polarity. While as contrast, the maximal fluorescence wavelength of the dyes showed somewhat dependence on the solvent polarity. In particular, C1 displayed well-separated dual fluorescence spectroscopy. The second fluorescence peak was characterized with an "abnormal" fluorescence emission wavelength in aprotic solvents with large Stokes shift (ca. 140 nm in THF), which was much more than normal Stokes shift (ca. 30 nm in THF). This emission spectroscopy could be assigned to ESIPT emission. On the other hand, the ESIPT fluorescence of C1 was much reduced or lost in the protic solvents. While, only normal fluorescence emission was detected in various solvents. Although the absorption maxima of C1 exhibited about 10 nm red-shift with respect to those of C2, the normal fluorescence maxima of C1 and C2 were almost identical in various solvents. These results suggested that C1 could undergo ESIPT, but C2 was not able to proceed ESIPT. The molecular geometry optimization of phototautomers in the ground electronic state (S0) was carried out with HF method (Hartree-Fock) and at DFT level (Density Functional Theory) using B3LYP both, while the CIS was employed to optimize the geometries of the first singlet excited state (S1) of the phototautomers of C1 and C2 respectively. The properties of the ground state and the excited state of the phototautomers of C1 and C2, including the geometrical parameter, the energy, the frontier orbits, the Mulliken charge and the dipole moment change were performed and compared completely. The data were analyzed further based on our experimental results. Furthermore, the absorption and fluorescence spectra were calculated in theory and compared with the measured ones. The rate constant of internal proton transfer (9.831×1011 s−1) of C1 was much lower than that of salicylidene methylamine (C3, 2.045×1015 s−1), which was a typical Schiff base compound and was well demonstrated to undergo ESIPT easily under photoexcitation. more...

This paper presents the investigation of tuning the color and photoluminescence of a range of triphenylamine- based derivatives with various substituent groups. The ultraviolet/visible absorption and fluorescence spectroscopy of the derivatives showed remarkable difference. The molecular geometry optimization demonstrated that the properties of the ground state and the excited state of the compounds have a close relationship with the substituent groups. Therefore, it is possible to tune the color and photoluminescence of the derivatives at molecular level. The cyclic voltammograms of these compounds were detected in methylene chloride at various scan rates. The thermal stabilities of the compounds were analyzed with the different scanning calorimetry and the thermogravimetry. more...

This paper presented comprehensive theoretical investigation of excited state intramolecular proton transfer (ESIPT) of four new large Schiff base derivatives with extended conjugated chromophores. The properties of the ground state and the excited state of phototautomers of C1 to C4 [C1: 2-(4′-nitro-stilbene-4-ylimino)methylphenol; C2: 2-(4′-cyano-stilbene-4-ylimino)methylphenol; C3: 2-(4′-methoxyl-stilbene-4-ylimino)methylphenol; C4: 2-(4′-N,N-diethylamino-stilbene-4-ylimino)methylphenol], which included geometrical parameter, energy, rate constant, frontier orbit, Mulliken charge, dipole moment change, were studied by DFT (density functional theory), CIS (configuration interaction singles-excitation), TDDFT (time-dependent DFT) methods to analyze the effects of chromophore part on the occurrence of ESIPT and the role of substituent groups. The structural parameter calculation showed that the shorter RHN and larger ROH from enol to enol* form, and less twisted configuration in the excited state implied that these molecules could undergo ESIPT as excitation. Stable transition states and a low energy barrier were observed for C1 to C4. This suggested that chromophore part increased some difficulty to undergo ESIPT for these molecules, while the possibility of occurrence of ESIPT was quite high. The negative ΔE* (−9.808 and −9.163 kJ/mol) of C1 and C2 and positive ΔE* (0.599 and 1.029 kJ/mol) of C3 and C4 indicated that withdrawing substituent groups were favorable for the occurrence of ESIPT. The reaction rate constants of proton transfer of these compounds were calculated in the S0 and S1 states respectively, and the high rate constants of these compounds were observed at S1 state. C1 even reached at 1.45×1015 s−1 in the excited state, which is much closed to 2.05×1015 s−1 of the parent moiety (salicylidene methylamine). Electron-donating and electron-withdrawing substituent groups had different effects on the electron density distribution of frontier orbits and Mulliken charges of the atoms, resulting in different dipole moment changes in enol*keto* process. These differences in turn suggested that C1 and C2 had more ability to undergo ESIPT than C3 and C4. The ultraviolet/visible absorption spectra, normal fluorescence emission spectra and ESIPT fluorescence emission spectra of these compounds were predicted in theory. more...

In this article, we presented novel nitro-stilbene derivatives with one or two benzophenone groups as photoinitiators via multi-steps synthesis. The ultraviolet/visible spectroscopy and the emission spectroscopy of the compounds were determined in various solvents. The results showed that the ultraviolet/visible absorption spectroscopy of the derivatives with benzophenone moiety displayed overlap effects of nitro-stilbene and benzophenone parts. In non-polar solvents, the derivatives exhibited strong emission, while they displayed weak emission in modest and strong polar solvents. Dyes-linked benzopheonone groups displayed stronger fluorescence emission than simple chromophore parent molecules. Visible-light photoinitiating effects of the derivatives were investigated extensively. Methyl methacrylate could be photoinitiated efficiently by the derivatives with benzophenone moieties at very low concentration, even at 1 x 10(-5) mol/L. While the photopolymerization efficiency of styrene initiated by the derivatives was lower than that of methyl methacrylate. Our results showed that the dye-linked photoinitators had more efficient photoinitiating than the simple mixture of dye and photoinitator. Furthermore, the derivative with two benzophenone groups displayed more excellent photoiniatiating effects than the derivative with one benzophenone group. Thermodynamics driving for the occurrence of visible-light photoinduced intramolecular electron transfer from chromophore part to benzophenone part was evaluated. Benzopinacol moiety produced in photoreaction was confirmed by nuclear magnetic resonant spectroscopy. Thermal stability of the derivatives was analyzed. more...

Suitable chemical strategy is a useful approach on the tuning color and photoluminescence of organic dyes. This paper presented tuning novel branched p-nitro-stilbene derivatives efficiently with a new chemical strategy through variation of chemical bridged bond. Linking bonds played significant effects on the absorption and fluorescence spectroscopy of the branched p-nitro-stilbene derivatives. A change from "D-pi-A" to "A-pi-A" chemical structural characteristics occurred for the branched p-nitro-stilbene derivatives as ester bond was attached. This led to not only large hypsochromic shift of the maximal absorption wavelength of the branched p-nitro-stilbene derivatives, but considerable reduction of the fluorescence intensity. While in contrast, the branched p-nitro-stilbene derivatives with ether bond exhibited longer wavelength absorption and much stronger fluorescence emission in modest polar solvent. The cyclic voltammograms of these branched p-nitro-stilbene derivatives were determined. Different electrochemistry processes were observed for the branched p-nitro-stilbene derivatives with various linking bonds. The energies of frontier orbital of the branched p-nitro-stilbene derivatives were estimated from their corresponding redox potentials. Molecular geometry optimization of the branched p-nitro-stilbene derivatives was performed, and the electron density distribution of frontier orbital was analyzed. Thermal stabilities of these branched nitro-stilbene derivatives were investigated via the analysis of the differential scanning calorimetry (DSC) and thermograving (TGA) curves. This paper presented strong evidences that the absorption and fluorescence spectroscopy of the branched stilbene derivatives could be mediated efficiently by chemical strategy. more...

In this paper, we presented four novel visible light photoinitiating systems, which employed nitro-stilbenzene derivatives as photoinitiators. Visible light photopolymerization of these systems was studied completely. The results showed that the chemical structures of the photoinitiators, photoinduced electron transfer approach, solvent polarity, and monomers played significant effects on the visible light photopolymerization. The electrochemistry of nitro-stilbenzene was dramatically influenced by the linking benzophenone moiety. The cyclic voltammograms of four photoinitiators were determined and discussed. We further estimated the thermodriving force for electron transfer between nitro-stilbenzene and benzophenone. Thermal stabilities of new photoinitators were determined by the analysis of differential scanning calorimetry (DSC) and thermogravimetry (TG) in this paper. Copyright © 2009 John Wiley & Sons, Ltd. more...

The synthesis, characterization and spectroscopy of a range of novel substituted p-nitro-stilbene derivatives with different bridging bonds were presented. The molecular structure characterization was carried out with 1H NMR, 13C NMR and elemental analysis. The ultraviolet/visible spectroscopy and photoluminescence of the compounds were investigated in various solvents. The maximal absorption wavelength of the nitro-stilbene derivatives with an ether bond exhibited approximate 30 to 40 nm bathochromic shift compared to that of nitro-stilbene dyes with an ester bond. Furthermore, the nitro-stilbene derivatives with an ether bond displayed obvious photoluminescence, while the nitro-stilbene derivatives with an ester bond showed weak fluorescence emission. The detection of the cyclic voltammograms of the nitro-stilbene derivatives showed that the nitro-stilbene compounds with different linking bonds exhibited different redox proceses at various scan rates. The theroretical calculations of HOMO and LUMO energy of nitro-stilbene derivatives showed that the energy gaps between HOMO and LUMO of 3 and 4 were lower than those of 1 and 2. The electron density of the frontier orbitals of nitro-stilbene derivatives was observed to be affacted by the linking bonds, which thus made it possible to tune the spectroscopy of these dyes with chemical strategy. The differential scanning calorimetry and thermogravimetry showed that the thermal stabilities of these dyes were not much affected by the linking bond. The results presented in this paper would be great interest in development of ideal nitro-stilbene derivatives for special purposes. more...

Novel nitro-azobenzene dyes bearing one or two benzophenone branches were proposed and synthesized to improve their photophysical and photochemical properties. The new dyes exhibited double UV/visible bands, and they displayed weak fluorescence emission as excited at 350 nm. Single crystal X-ray diffraction data showed that two phenyl rings of azobenzene was almost coplanar, and the benzophenone part was neither coplanar nor linear connection with azobenzene via ether bridged bond, which have good fit with molecular geometry optimization calculation results. The cyclic voltammeric results of nitro-azobenzene dyes were firstly reported in this paper, which demonstrated that the electrochemical properties of nitro-azobenzene dyes was altered by the substitution of benzophenone part. Thermal stabilities of the new dyes were studied by the analysis of differential scanning calorimetry (DSC) and thermograving (TG) in this paper. Efficient visible-light photoinitiating polymerization of methyl methacrylate (MMA) by the novel nitro-azobenzene dyes was presented and discussed. more...

Background and objective Livin is a novel inhibitor of apoptosis protein (IAP), recent studies showed it overexpresses in a variety of carcinomas including lung cancer and contributes much to the cancerous development. The objective of this study is to explore the expression of livin in tissues of lung cancer and its relationshipwith histological types, chemotherapy, Lymph node metastasis and to study its correlation with the expression of pro-caspase3 as well. Methods Expressions of Livin and caspase3 were detected by Western blot assay in lung cancer tissues as well as in controls. Results Livin was expressed in 15 of 27 lung cancer, significantly more than those in lung para-cancerous (1/5) or benign disease lung tissues (2/12) (P 0.05). Conclusion Livin are differently expressed in different histological types of lung cancer; High levels of livin expression do not relate to chemotherapy, lymph node metastasis (P >0.05). The levels of livin tends to be positively associated with those of accordingly pro-caspase3, it is presumed that livin could bind pro-caspase3 and suppress its activation. more...

Objective To study the expressions of two isoforms of Livin in tissues of lung cancer and their relations to histological types and chemotherapy, and to study their correlations to the expression of caspase-3 as well. more...

A new method to correlate and estimate the solubility of fatty acids, alcohols, esters and triglycerides in supercritical CO2 is proposed. This method is based on the idea of molecular connectivity indices and Chrastil's equation. The Chrastil's equation was used to correlate the solubility of solutes in supercritical CO2 and the parameters in Chrastil's equation were expressed as the linear functions of the solutes’ molecular connectivity indices. This method proves to be simple because only knowledge on the chemical structure of the solute is needed. The results showed that the correlation coefficient was higher than 0.9662 in the correlation and the solubility can be predicted on an order-of-magnitude basis. more...

A new supercritical fluid extraction (SFE) pretreatment method for determination of tripterine in Tripterygium wilfordii Hook. F with high performance liquid chromatography is proposed in this paper. The optimized conditions of SFE were set as follows: n‐butanol was selected as cosolvent and the ratio of n‐butanol to the material was 1.0 mL/g material; the extraction temperature and pressure were 40°C and 35 MPa, respectively. The static and dynamic extraction times were both 15 min. Recovery of tripterine from SFE varied from 90.5 to 103.2% for samples with different content levels. During the validation of the method, the linearity and precision, stability, limit of detection and quantification were also determined, all of which satisfied the analytical requirements. Comparison of SFE with conventional soxhlet extraction shows SFE is more efficient in the extraction of tripterine, as it needs less organic solvent and extraction time. Besides, it does not need a further cleanup procedure before ... more...

Based on multiple embedding theory, traditional multi-scale entropy is optimized by local characteristic-scale decomposition (LCD) and fast kurtogram (FK) which can be called LFK for short. In the improved method, the vibration signal of rolling bearing is decomposed by LCD and the two component signals whose cross correlation coefficient with the original signal is bigger than others are selected. FK is applied for filtering the reserved component signal and highlighting the fault feature. Multivariate multi-scale entropy is extracted from the processed signal to characterize the degradation state of rolling bearings. Compared with multi-scale entropy of the original signal, multivariate multi-scale entropy has a better performance. more...

An online fringe projection profilometry (OFPP) based on scale-invariant feature transform (SIFT) is proposed. Both rotary and linear models are discussed. First, the captured images are enhanced by “retinex” theory for better contrast and an improved reprojection technique is carried out to rectify pixel size while keeping the right aspect ratio. Then the SIFT algorithm with random sample consensus algorithm is used to match feature points between frames. In this process, quick response code is innovatively adopted as a feature pattern as well as object modulation. The characteristic parameters, which include rotation angle in rotary OFPP and rectilinear displacement in linear OFPP, are calculated by a vector-based solution. Moreover, a statistical filter is applied to obtain more accurate values. The equivalent aligned fringe patterns are then extracted from each frame. The equal step algorithm, advanced iterative algorithm, and principal component analysis are eligible for phase retrieval according to whether the object moving direction accords with the fringe direction or not. The three-dimensional profile of the moving object can finally be reconstructed. Numerical simulations and experimental results verified the validity and feasibility of the proposed method. Published version more...

A new approach for large field of view measurement using the Shack-Hartmann wavefront sensor (SHWS) is proposed. The object to be measured is divided into several subaperture units. Each unit is measured using the SHWS and a new algorithm is applied to stitch these units. Both theoretical principle and experimental verification are provided in this paper. A comparison between the present global optimization stitching scheme with the conventional sequential stitching method highlights the benefits of the new system. Experimental validation of the SHWS stitching algorithm is carried out by using a coated mirror. Comparison is made with a phase shifting interferometer and good agreement is found. Lastly, a new methodology for large aperture measurement of optical components is provided. Published version more...

To solve the problem that there were non-sensitive features and over-high dimensions in the feature set of fault diagnosis, a new feature extraction method based on sensitive feature selection and nonlinear feature fusion for rolling element bearing fault diagnosis was proposed. CDET was utilized to choose features sensitive to fault severity from the high dimensional feature set, and weighted the selected sensitive features by their sensitive degree. The weighted sensitive feature subset was compressed with LPP to reduce its dimensions and get the compressed more sensitive feature subset, which can enhance the discrimination between all classes by improving the between-class scatter and within-class scatter for fault classification. Compared with the classification result of the original high dimensional feature set based on direct LPP without feature selection, the classification result of the proposed method has the advantages of higher compactness and higher computational efficiency. more...

New azulene derivatives containing resonantly electron withdrawing formyl and resonantly electron donating fluorine substituents on the seven- as well as the five-member ring have been prepared. Systematic color changes as a result of perturbation of HOMO, LUMO, and LUMO + 1 energies were discussed. Corresponding excited-state properties related to S2-fluorescence were determined. more...

A novel quantitative 3D imaging system of silicon microstr uctures using InfraRed Transport of Intensity Equation (IR-TIE) is proposed in this paper. By reco rding the intensity at multiple planes and using FFT or DCT based TIE solver, fast and accurate phase retrieval for both un iform and non-uniform intens ity distributions is proposed. Numerical simulation and experiments confirm the accuracy and reliability of the proposed method. The application of IR-TIE for inspection of micro-patterns in visibly opaque media using 1310 nm light source is demonstrated. For comparison, micro-patterns are also inspected by the contact scanning mode Taylor Hobson system. Quantitative agreement suggests the possibility of using IR-TIE for phase imaging of silicon wafers. Keywords: infrared imaging; phase retrieval; defocuse d intensity; transport of intensity equation 1. INTRODUCTION Silicon wafers are wildly used in ultra- large-scale integration (ULSI) and micr o-electro-mechanical system (MEMS), in quality control process it’s very important to assess the yielding microstructure etched on or inside the wafer. The conventional mechanical probe processes may cause substrate scratch, moreover it costs more time due to mechanical movements. Non-invasive phase imaging techniques has gained more attractions. There are several main types of quantitative phase imaging (QPI): off-axis, phase-shifting, co mmon-path and white-light where TIE can be considered of the fourth category [1]. This technique is based on the theoretical formalism developed by Teague [2]. TIE imaging relies on the derivatives of the wave equation in the paraxial approximation. It works under coherent illumination (usual laser) also capable with partially coherent field. Direct phase retrieval from intensity measurements using the TIE has begun to enter the actual application [3, 4]. Infrared (NIR) imaging plays a big role in non-destructive testing in medicine, aerospace and semiconductor industries. For silicon wafers normally visible light cannot pass through, whereas it’s transparent in IR range. Existing 3D IR visualization systems are mainly based on interferometric methods such as optical coherence tomography (OCT) or time consuming measurement processes as in the case of IR confocal microscopy. In this paper we seek to develop a novel type of method for quan titative 3D IR imaging. Our new system can be an alternative for subsurface meas urement applications such as non-destr uctive testing and medical imaging (eye biomedical diagnostic). This prototype is non-interferometric and inexpensive compared to existing solutions. Additionally, by using tunable lens [5] (electrically monitored) the system is capable for real time imaging at millisecond temporal resolution which broadened the spectrum of possible applications. With the vigorous development of the high-precision imaging industry, the whole setup can be mounted on a commercial inverted bright-field microscope [6], it lays the foundation for functionalization and industrialization. more...

Antimicrobial treatment of multidrug-resistant Acinetobacter baumannii (MDR-AB) infections continues to pose significant challenges. With limited options, clinicians have been pushed towards using unorthodox combinations of licensed antibiotics. Although daptomycin/colistin combination appears to be a promising treatment option based on in vitro data, further preclinical work is needed. In this study, the A. baumannii-Galleria mellonella system was employed to study the in vivo efficacy of this combination in order to determine whether it should be explored further for the treatment of MDR-AB infections. The antimicrobial activity of colistin alone and in combination with daptomycin was assessed versus an A. baumannii type strain (ATCC 19606) and a MDR-AB clinical strain (GN2231) isolated in Anhui, China. Synergy studies were performed using the microtitre plate chequerboard assay and time-kill methodology. The in vivo activity of daptomycin/colistin combination was assessed using a G. mellonella larvae model. The combination of daptomycin and colistin was bactericidal against both strains tested. In chequerboard assays, daptomycin was highly active against A. baumannii when combined with colistin [fractional inhibitory concentration index (FICI) of more...