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Conventional assays for identifying polymorphism of aldehyde dehydrogenase 2 (ALDH2) gene (rs671) are based on electrophoresis, fluorescence-labeled probes or sequencing, which are laborious and expensive. Herein, we proposed a visualized detection of ALDH2 genotype by PCR-based serial invasive reaction coupled with gold nanoparticle probe (GNP) assembling, in which target DNAs were firstly amplified by PCR, and then the alleles on the amplicons were identified by serial invasive reaction, and finally the genotyping results could be read out with naked eyes by observing the color changes caused by GNP assembling. If the allele-specific invasive probe matched the target sequence, the hairpin probe could be cleaved into two parts by Flap endonuclease 1 (FEN1). As a result, the GNPs could not be aggregated by the hairpin probe, keeping the solution red. Otherwise, the intact hairpin probe caused the aggregation of GNPs, leading to the color change from red to purple or clear. Therefore, the genotyping result could be read out with naked eyes by observing the color changes of the reaction. As low as 80 pg of genomic DNA could be accurately genotyped, and the genotyping results of 207 clinical samples were consistent with that of pyrosequencing, indicating that the proposed method has great potential in genotyping of personalized medicine-related single nucleotide polymorphism.

Fractional-order nonlinear multi-agent systems with distributed and input delays are considered, in which the topology of multi-agent system corresponds to a directed weighted graph or an undirected weighted graph. Several algebraic conditions on leader-following consensus are presented by using fractional-order Razumikhin approach and algebraic graph theory. Finally, we present two numerical examples to illustrate those conditions proposed are feasible and convenient to evaluate consensus.

This article considers fractional coupled networks with discrete and distributed delays, an algebraic criterion on global synchronization is derived by using fractional Razumikhin approach and matrix inequalities. Furthermore, two types of special fractional delayed networks are also investigated and several simple sufficient conditions on global synchronization are presented, respectively. Finally, two numerical examples are provided to demonstrate the validity of our theoretical results.

This paper deals with global synchronization of fractional complex networks with non-delayed and delayed couplings. Applying fractional Razumikhin theorem, a simple quadratic Lyapunov function is constructed and two linear matrix inequality (LMI) criteria on global synchronization are proposed. It is very convenient and efficient to check synchronization of the presented network models by using our proposed method. Finally, numerical simulations are given to show the efficiency of the obtained results.

Forty-seven surface pollen samples and 141 vegetation quadrats were investigated in the Lhasa Valley in order to assess the relationships between local modern pollen assemblages and vegetation and climate. The regional climatic data for each sample are mean annual precipitation (Pann), mean annual temperature (Tann), summer temperature (Tsummer), actual evapotranspiration (AET), potential evapotranspiration (PET), and moisture index (MI), estimated by co-kriging using meteorological data from 16 climate stations in or near the Lhasa Valley. Cluster analysis, principal components analysis (PCA), Procrustes analysis, and co-correspondence analysis (Co-CA) were used to evaluate the relationship between modern pollen assemblages and contemporary vegetation. Linear regression was used to examine the relationships between pollen ratios (Artemisia/Chenopodiaceae (A/C), Artemisia/Cyperaceae (A/Cy), Artemisia + Chenopodiaceae/Cyperaceae (AC/Cy)), aridity pollen index, total arboreal pollen (AP), and the climatic variables. Cluster analysis and PCA results are generally consistent, and differentiate between pollen assemblages from arid conditions and those from more humid conditions. However, the PCA results distinguish pollen assemblages from shrubland slightly more clearly than the cluster analysis does. The PCA results show a general agreement between the modern pollen assemblages and contemporary vegetation types, but pollen assemblages from coniferous (Juniperus) woodland cannot be distinguished from shrub grassland, meadow, or shrub meadow pollen assemblages in the PCA results. Both Procrustes analysis and associated permutation tests and Co-CA show a strong statistically significant relationship between modern pollen and vegetation composition. Analysis of the relationship between the climatic variables and vegetation types suggests that humidity (Pann and MI) is the main variable related to the vegetation types within the restricted areas of the Lhasa Valley. Neither the A/C ratio nor the aridity pollen index is a reliable aridity indicator in the Lhasa Valley. The AP sum may be a weak precipitation indicator, whereas the A/Cy and AC/Cy ratios appear to be robust indicators of precipitation, aridity, and temperature at the scale of the Lhasa Valley.

In this paper, the asymptotical stability of Riemann–Liouville fractional neutral systems is investigated. Applying Lyapunov direct method, we present new sufficient conditions on asymptotical stability in terms of linear matrix inequality (LMI) which can be easily solved. The advantage of our employed method is that one may directly calculate integer-order derivatives of the Lyapunov functions. Finally, two simple examples are given to show that the proposed method is computationally flexible and efficient.

The main determinant of crop yield is seed yield. In Arabidopsi, many of the genes that regulate seed number are involved in gametophyte and zygote development, and their overexpression cannot increase seed number. However, several mutants with enhanced brassinosteroid (BR) and cytokinin (CK) signals show increased seed number per silique (SNS). Here, we studied the crosstalk between BR and CK signals in regulating SNS through crossing BR- and CK-related mutants. Compared with the mutants ckx3 ckx5 and bzr1-1D , the triple mutant ckx3 ckx5 bzr1-1D with enhanced BR and CK signals formed elongated placentae and showed increased ovule initiation and SNS, indicating that BR and CK synergistically up-regulate SNS. Although BR enhanced the CK signal and CK enhanced the BR signal, while CK partially rescued the phenotypes of BR deficient- and -insensitive mutants, BR could not rescue the phenotypes of CK-deficient mutants. This suggested that CK functions downstream of BR in regulating SNS and that BR regulates SNS through CK-mediated or CK-independent pathways. Comparative transcriptome analyses of ckx3 ckx5 , bzr1-1D , and ckx3 ckx5 bzr1-1D identified known and new genes involved in ovule initiation. The BR-induced transcription factor BZR1 was found to directly interact with the B-type regulator of CK, ARR1, and this interaction enhanced the ability of ARR1 to target and induce genes related to ovule development. Our results demonstrate that BR and CK synergistically increase SNS through co-regulating downstream genes involved in ovule identity and initiation. The genes involved in this process have potential applications in enhancing crop yield.

In order to understand how Late Mesoproterozoic to Early Neoproterozoic orogenic belts evolved during the assembly and rifting of the supercontinent Rodinia, we have carried out detailed studies on the geochemical compositions of Early Neoproterozoic crust across the Jiangnan orogen (JO) which connects the Yangtze and Cathaysia blocks on the northwestern margin of Rodinia. A gradual geochemical variation is recognized from east to west, based on comparisons of whole-rock Nd isotopes, U–Pb age spectra of detrital zircons, and Hf isotopes in magmatic zircons and detrital zircons from the Neoproterozoic granitoids and metasedimentary basement sequences in the JO. LA-ICP-MS U–Pb dating of detrital zircons from the sediments and magmatic zircons from interlayered volcanic rocks suggests that the folded basement sequences formed within the span 860–825 Ma, implying the final amalgamation of the Yangtze and Cathaysia blocks occurred no older than ca 825 Ma. The 950–820 Ma detrital zircons strongly dominate in the eastern basement sequences, and most of them show moderately to highly positive ɛHf(t). In contrast, many of the Early Neoproterozoic detrital zircons in the western JO have moderately negative ɛHf(t) and more older (>1.0 Ga) detrital zircons were found in this area. We suggest that the metasedimentary basement sequences in the JO were deposited in retro-arc foreland basins which originally evolved from back-arc basins, and the change of provenance controlled the variation in crustal geochemistry of crust across the JO. Sediments in the eastern basement sequences have been sourced mainly from the juvenile subduction-related igneous rocks to the east, with a few from the central Yangtze Block, whereas those in the western JO may have been located far from arc terranes to the east and thus received more older recycled detritus from the southern part of the South China Block. Moreover, the Hf isotopes of the detrital zircons imply episodic crustal growth in the provenance of the JO metasedimentary basement sequences, with age peaks at 1.0–0.8 Ga, 1.75–1.50 Ga and 2.60–2.45 Ga. The early crust in South China may have been formed mainly at around 3.8 Ga ago, and contains some Hadean components (ca 4.1 Ga).

A kind of chiral azobenzene amphiphile, N -[4-(4-dodecyloxyphenylazo)benzoyl]- l -glutamic acid (C 12 -Azo- l -Glu; as shown in Fig. 1), was synthesized and the self-organization properties on solid substrates were investigated. C 12 -Azo- l -Glu underwent a reversible trans – cis photoisomerization in dilute solution. While the photoisomerization was suppressed on solid substrate because of the H-aggregation, indicating the formation of compact film. When C 12 -Azo- l -Glu was cast from ethanol solution onto the hydrophilic surface of mica, a stable flat-layered structure formed spontaneously in large scale. High-resolution images allowed the identification of the relative orientation of molecular rows in the ordered thin film and the crystal lattice of mica. A molecular packing model of the layered structure was proposed. There was a template effect of mica to the self-organization process. Hydrogen bonding, π–π interaction and the chiral center in the molecule played the important roles in the self-organization process. The cooperative competitive effect between them led to the highly ordered structure.

The interfacial-dependent self-organization of a chiral amino acid amphiphile was observed on various substrates with different surface hydrophobicity. Three kinds of organizations are induced at different substrates, which appear as helical aggregates on hydrophobic surface (e.g. highly oriented pyrolytic graphite), molecular flat layer on hydrophilic surface, (e.g. mica) and a transition state between them on silicon wafer. The strength of the interactions between the helical aggregates formed in solution and the substrate is the key factor to the self-organization of the chiral molecule. The results reported here provide insight into how the surface hydrophobicity of substrates affects the self-organization of chiral molecules.

Holographic gratings were optically recorded by two beams from a He–Ne laser operating at 632.8 nm in poly (methyl methacrylate) (PMMA) film containing push–pull azo dye. The holographic characteristics of the recorded gratings were dependent on the polarization direction of the recording beams and the relationship between the diffractive signals and the power density of recording beams was investigated. The formation of holographic gratings accompanied by 532 nm (double-frequency of Nd:YAG laser) irradiation was studied in detail. It was found that the effect of 532 nm laser to the holographic grating lay in two aspects. The acceleration effect of 532 nm laser to the formation of holographic grating is predominant when the power density of 532 nm laser is low. While at relatively high power density of 532 nm laser, the erasure is the main factor to the holographic grating. Moreover, the holographic grating was probed by 532 nm laser at low power density and the dependence of the first order diffractive signal on the recording beam power density was also presented.

An azobenzene derivative 4-hydroxy-3′-trifluoromethyl-azobenzene (FAzoH) was synthesized and the physisorbed monolayers of the molecule at the liquid/solid interface were investigated by scanning tunneling microscopy (STM). The acquired STM images exhibit the molecular packing of the monolayers of FAzoH in trans conformation. Following the UV light (365 nm) induced trans–cis isomerization, stable domains of pure cis isomers have been identified by STM. The results suggest that a strong hydrogen bonds network existing in the monolayer stabilizes the domains of the cis isomer.

Topography and electric property of the physisorbed monolayer of an azobenzene derivative, 4,4′-dihexyloxy-2-hydroxy-azobenzene (Azo), at the liquid/graphite interface were investigated by scanning tunneling microscopy (STM). The STM observations show that the azobenzene derivative can form an ordered row-like structure at the interface and the periodicity of the row is 3.0 nm, corresponding to the length of the molecule. Electric property of this organic tunnel junction at the liquid/graphite interface was examined by the measurement of the current–voltage (I–V) curve. The I–V curve is asymmetric for positive and negative voltages, indicating the rectifying behavior of the adlayer.

Azobenzene-containing liquid crystal, 2-hydroxy-4-hexyloxy-4′-hexyloxy azobenzene (AB), was synthesized and used to produce LB films. The surface pressure vs surface area isotherm showed that the liquid crystal molecules formed a stable multilayer on the water subphase owing to the self-assembly for their much smaller area per molecule with 0.1 nm 2 at π =0 and 0.07 nm 2 at collapse point. This spontaneous behavior was also confirmed by small angle X-ray diffraction for a ‘horizontally once-transferred’ LB film. The ‘vertically multi-transferred’ LB film also exhibited the same ordered layer structure with the long spacing of the multilayer about 2.0 nm. Polarized FTIR spectra were used to measure the orientation of liquid crystal molecules in LB films with a tilt angle of 60° and 48° (corresponding to azobenzene moiety and hydrocarbon chain, respectively), which is well in accordance with the result of X-ray diffraction. The result from UV–vis absorption spectra revealed that the AB molecule formed H-aggregation in LB films.

Oligomer-polymaleic acid octadecanol esters (PMAO) with different ratios between carboxylic groups and hydrocarbon chains stabilized CdS nanoparticles were produced in the form of reversed micelles. The PMAO-capped CdS nanoparticles were transferred from the air–water interface onto CaF 2 and silicon substrates. Surface pressure–area isotherms gave the information that both the two kinds of pure PMAO and PMAO-capped CdS could form stable monolayers on the water subphase. From the area occupied by average molecular unit (0.24 and 0.11 nm 2 ), it was concluded that the size of two kinds of PMAO-capped CdS nanoparticles was different. The results of UV-vis spectra gave us information that the diameter of CdS nanoparticles could be controlled to less than 2 nm. The measurement of Fourier transform infrared spectroscopy (FTIR) confirmed the formation of CdS. The average tilt angle of hydrocarbon chains revealed by polarized IR spectra was 50 and 60°, respectively. The long spacing of the multilayer of PMAO-capped CdS determined by small angle X-ray diffraction was 6.3 and 4.8 nm, which also maintained the conclusion that the ratio between carboxylic groups and hydrocarbon chains effect the size of reversed micelles.