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Two new triterpenoids, 2α,3β,16α,19α,23-pentahydroxyolean-12-en-28-oic acid (1) and 2α,3α,11α,21α,23-pentahydroxyurs-12-en-28-oic acid (2), were isolated from the aerial parts ofCallicarpa kwangtungensis. Their structures were elucidated by 1D and 2D analyses, as well as MS and IR spectra. [ABSTRACT FROM PUBLISHER]

This work focuses on an improved method that enables us to measurein situGaN film photoluminescence (PL) under Ar or N2plasma etching. Although the background signal is large and increases with bias voltage, the GaN PL can be obtained after subtraction of this background from the total luminescence. Moreover, after plasma etching, the intensities of the near-band-edge and the yellow luminescence decrease significantly. It is suggested that this behaviour is strongly related to the heavy plasma-induced damage, which includes non-radiative defects and deep-level defects, such as Ga vacancies and/or C impurities. [ABSTRACT FROM AUTHOR]

The present study examined sequence variations in three mitochondrial DNA (mtDNA) regions, namely, NADH dehydrogenase subunit 5 ( nad5), adenosine triphosphate subunit 6 ( atp6) and cytochrome c oxidase subunit 3 ( cox3), among Oesophagostomum asperum isolates from different regions in Shaanxi and Hunan provinces, China. The lengths for partial sequences of nad5 (p nad5), atp6 (p atp6) and cox3 (p cox3) were 427 bp, 381 bp and 337 bp, respectively. The intra-specific sequence variations among all O. asperum samples were 0-2.11%, 0-1.84% and 0-1.48% for p nad5, p atp6 and p cox3, respectively, while the inter-specific sequence differences among Oesophagostomum species in pig and small ruminants were 18-21.3% for p nad5, 18.3-24.5% for p atp6 and 10.6-13.7% for p cox3. A phylogenetic analysis based on combined sequences of three mtDNA fragments indicated that all O. asperum isolates were grouped in one solid clade, and the Oesophagostomum spp. from pig were located in another clade. However, these mtDNA fragments could not reveal genetic relationships of geographical isolates of O. asperum in China. These results provided valuable information for studying population genetics of Oesophagostomum spp., and for controlling Oesophagostomum infection in animals as well as humans. [ABSTRACT FROM AUTHOR]

1. The aurantio-obtusin's glucuronide was detected when aurantio-obtusin was incubated with human liver microsomes (HLMs). Recombinant UGT isoforms screening experiment showed that UGT1A8 was the major isoform contributed to the glucuronidation. 2. The metabolic profiles for aurantio-obtusin in liver microsomes from different species were similar, however, the intrinsic clearance values ( Vmax/ Km) among the species were: Monkey > Human > Rat > Rabbit > Dog > Pig > Mouse > Guinea pig. [ABSTRACT FROM AUTHOR]

Arsenic-bearing pyrite was used as an indicator to investigate microwave roasting behavior of pyrite concentrates. Appearance of the microwave roasted sample showed that the irradiation-induced transformation started from a small area of the crucible and gradually advanced to the remainder zone. X-ray diffraction (XRD) analysis showed that the arsenic contained in the pyrite was oxidized to As2O3, and that the pyrite was converted into pyrrhotite, hematite, and Fe3O4. The effect of the microwave power, the sample mass, and the microwave irradiation time on the roasting properties was also studied. The results showed that the mass loss ratio increased with the microwave power and the microwave roasting time. [ABSTRACT FROM AUTHOR]

The present study examined the variations in three mitochondrial (mt) DNA sequences, namely cytochrome b ( cytb), cytochrome c oxidase subunit 3 ( cox3) and NADH dehydrogenase subunit 5 ( nad5), among Baylisascaris schroederi isolates from the Qinling subspecies of the giant panda in Shaanxi province, northwestern China. No differences in length were detected in the three mt fragments from different isolates. The intra-specific sequence variations within all B. schroederi samples were 0-2.6% for p cytb, 0-1.8% for p cox3 and 0-2.1% for p nad5, while the inter-specific sequence differences among members of the genus Baylisascaris were 8.2-15.2%, 6.2-15.9% and 8.4-16.0% for p cytb, p cox3, p nad5, respectively. A phylogenetic analysis of the combined sequences of p cytb, p cox3 and p nad 5 showed that all B. schroederi samples in the present study were located in two large clusters, with one cluster containing samples from giant pandas in Sichuan province. These findings provide basic information for further study of molecular epidemiology and control of B. schroederi infection in the Qinling subspecies of the giant panda and throughout China. [ABSTRACT FROM AUTHOR]

Owing to the second-order fiber Bragg grating possessing narrower reflectivity bandwidth than first-order, an all-fiber spectroscopic filter with several second-order fiber Bragg gratings and optical fiber couplers in the visible region is designed to extract interest rotational Raman spectra. Considering the inference fringe visibility of inscribing fiber Bragg grating and the fiber core index dispersion effect, numerical simulations are made by the improved mathematical model based on an exponential photorefractive dynamic, and its simulative results show better agreement with the experimental data. We propose an all-fiber spectroscopic configuration, which could balance lidar sensitivity against signal-to-noise ratio for optimizing remote sensing performance by fiber Bragg gratings serially. Simulative results show that the thumb principle for fabricating second-order fiber Bragg grating is the increasing gratings length, and that this all-fiber spectroscope can achieve >70 dB suppression to elastic scattering and efficiently extract the rotational Raman signal for profiling atmospheric temperature. [ABSTRACT FROM AUTHOR]

The photoluminescence of n-type GaN thin films in an argon plasma condition has been studied byin situmeasurement. The characteristic near-band-edge (NBE) peak and yellow luminescence (YL) of GaN films are observed in the spectra. However, compared to the luminescence of GaN in air and in a vacuum, in the plasma of 80 W power, the NBE peak and YL intensity first increase dramatically and then decrease with extended time. The effects are attributed mainly to an increasing temperature induced by the plasma, but also to a lesser extent by damage to the film caused by the plasma. [ABSTRACT FROM PUBLISHER]

The single nucleotide polymorphism (SNP) rs16754 of the WT1 gene has been described as a possible prognostic marker in patients with acute myeloid leukemia (AML). However, the results in this field are not reproducible in different cohorts. In this study, we investigated WT1 mutations, expression levels and SNP rs16754 in a cohort of 122 adult patients with AML. As the major allele (65.6%) in a Chinese population, WT1GG was associated with younger age (≤ 60) and lower percentage of blasts than WT1GA/AA. Meanwhile, improved overall survival (OS, p = 0.035) and disease-free survival (DFS, p = 0.021) were observed in WT1GG compared with WT1GA/AA. We then found that WT1 mutation, occurring in 8% of patients with AML, did not predict clinical outcome. Finally, WT1 levels were higher in patients with WT1GG than in those with WT1GA/AA. However, high levels of WT1 (> median) predicted worse OS ( p = 0.015) and DFS ( p = 0.034) than low levels of WT1 (≤ median). However, further studies are required to elucidate the mechanism of why WT1GG, which was associated with higher median expression of WT1 that predicts worse OS and DFS compared to low expression of WT1, predicted better OS and DFS compared with WT1GA/AA. In summary, WT1 rs16754 and WT1 expression have a significant impact on clinical outcome in patients with AML. [ABSTRACT FROM AUTHOR]

The genetic variations in three mitochondrial DNA (mtDNA) regions, namely portion of cytochrome c oxidase subunit 1 (p cox1), NADH dehydrogenase subunit 1 (p nad1) and cytochrome b (p cytb), were examined for Dicrocoelium dendriticum samples isolated from different origins in Shaanxi Province, northwestern China. The intra-specific sequence differences within D. dendriticum samples were 0-0.52% for p cox1, 0-0.73% for p nad1 and 0-0.58% for p cytb. Phylogenetic analyses based on combined sequences of three mtDNA showed that all D. dendriticum samples were clustered together in same clade of Paragonimus westermani. But the phylogenetic trees could not reveal geographically genetic relationships of D. dendriticum isolates in this province. These findings will provide basic information for further study of molecular epidemiology and control of D. dendriticum infection in this province as well as in China. [ABSTRACT FROM AUTHOR]

The complete mitochondrial genome (mitogenome) of Quasipaa exilispinosa (Anura: Dicroglossidae) we sequenced can provide critical information for mitogenome evolution. This mitogenome with 17,046 bp long contains 13 protein-coding genes (PCGs), 22 transfer RNA genes, two ribosomal RNA genes, and one non-coding regions. The overall AT content of 58.6%. The data using Bayesian phylogenetic inference supports the close relationship with Q. spinosa from the genus Quasipaa. Our results will be helpful for detail study on phylogenetic relationships of the related taxa. [ABSTRACT FROM AUTHOR]

The complete mitochondrial genome of Putian Loquat longicorn (Anoplophora chinensis) was determined in this study. Its mitochondrial genome (15,871 bp) contains 13 protein-coding genes, 22 tRNA genes, two ribosomal RNA genes (12S rRNA and 16S rRNA), and one large non-coding region (D-loop region). Nine protein-coding genes and fourteen tRNA genes are encoded on the H strand, and the other four protein-coding genes, two rRNA genes, and eight tRNA genes are encoded on the L strand. The arrangement of genes is identical to all know Longhorn beetle mitochondrial genomes. The complete mitochondrial genome of the A. chinensis provides an important data set for further study on its classification. [ABSTRACT FROM AUTHOR]

16-Isopropyl-5, 9-dimethyltetracyclo [10.2.2.01, 10.04, 9] hexadec-15-ene-5, 14-dicarboxylic acid (1b) was prepared from rosin through a Diels–Alder addition reaction. Then, a group of Schiff bases derived from 1b was synthesised. Their structures were characterised by IR,1H-NMR, MS and elemental analysis. The antibacterial activities of these newly synthesised Schiff bases were also investigated. The results show that these compounds possess antibacterial activities against Staphylococcus aureus and Escherichia coli. Among them, compounds 5a, 5b and 5c, exhibit remarkable antibacterial activity against E. coli. [ABSTRACT FROM AUTHOR]

Drop-weight experiments are performed on a thin layer of cyclotetramethylene tetranitramine (HMX) explosive crystals. The drop-weight impact machine is equipped with high-speed photographic systems. Experimental results show the effects of drop heights, mass of particles, and distributed density on compaction, deformation, transparency, reaction violence, and burning propagation. The aim is to establish a link between mechanical and thermal responses for a single layer of granular explosives. Minimum input energy and adequate number of particles, as well as sufficient mutual interactions among particles in the granular explosive sample, are necessary prerequisites for hot spot ignition and growth to burning. The course of the response, instead of a simple “go” or “no go” criterion is emphasized as a critical consideration in ranking material sensitivity. [ABSTRACT FROM AUTHOR]

A small-size gas-tight optical measuring system for detection of ammonia nitrogen in water was prepared based on gas-phase ammonia induced color change of the sensing element that was made by loading bromothymol blue (BTB) in a transparent porous glass fiber membrane. The gas-tight optical measuring system consists of a gas-testing and a liquid-sample chamber connected with each other by means of tubes and a mini-pump that cycles the gas between the two chambers. A 625-nm light emitting diode (LED), a photodetector and a sensing element were mounted in the gas-testing chamber for optical response to ammonia gas released from the water in the liquid-sample chamber. Release of ammonia gas was realized by alkalinizing the water sample with NaOH. Owing to the amount accumulation of ammonia gas in the sealing system, the ammonia nitrogen detection limit of the device can be very low. A small concentration of ammonia nitrogen, as low as 0.05 mg/L, was detected. The two linear-response ranges from 0.05 mg/L to 0.26 mg/L and from 0.26 mg/L to 2.62 mg/L were obtained. A relative standard deviation of ≤1% was determined by multiple measurements of the same sample. [ABSTRACT FROM AUTHOR]

A polyoxomolybdate, [Cu2(pz)(Mo3O10)] n (pz = pyrazine) (1), has been synthesized hydrothermally and characterized by elemental analysis, IR, X-ray photoelectron spectra, and thermogravimetric analysis. Single-crystal X-ray diffraction demonstrates that 1 has a 3-D architecture constructed by combination of {Mo3O10} units and [Cu2(pz)]2+. All the terminal oxygen atoms of the polyoxomolybdate are coordinated by univalent copper. Pyrazine came from in situ decarboxylation of 2-pyrazinecarboxylic acid and Cu+ from the in situ reduction of Cu2+ during the hydrothermal synthesis. [ABSTRACT FROM PUBLISHER]

Objective: The current prospective randomized study was designed to evaluate the safety and efficacy of combined intrapleural cisplatin and OK-432 (picibanil) plus hyperthermotherapy in patients with malignant pleural effusion (MPE). Methods: A total of 358 patients with MPE due to end-stage malignancies were enrolled and randomly divided into two groups, A and B: the intrapleural combination of cisplatin and OK-432 with hyperthermotherapy (n == 179) or without hyperthermotherapy (n == 179), respectively. Mild toxicities such as nausea, vomiting or anorexia, bone marrow depression, and pyrexia were similar in both groups. Result: Patients in Group A (with hyperthermotherapy) showed a significantly higher overall response (93.4%%) compared to those in Group B (79.8%%, χ2 == 43.11, p < .05). The median survival time for patients in Group A and Group B were 8.9 and 6.2 months, respectively ( p > .05). After treatment, the quality of life scores were significantly increased in both groups as compared to prior treatment ( p < .05). Conclusion: In conclusion, our study suggests that combined intrapleural cisplatin and OK-432 followed by hyperthermotherapy are more effective in the control of MPE and improve patients' quality of life. [ABSTRACT FROM AUTHOR]

Two new xanthones, angustins A and B (1 and 2), were isolated from the aerial parts of Swertia angustifolia together with six known compounds (3–8). The structures of these two xanthones were elucidated by extensive analysis of the spectroscopic data. In addition, compounds 3 and 6–8 were isolated from this plant for the first time. [ABSTRACT FROM PUBLISHER]

The jet swell effect in the wet spinning of polyacrylonitrile (PAN) fiber was studied by optical microscopy and the jet swell ratio was obtained through directly measuring the diameter of the freely extruded fibers. For reflecting the actual drawing situation of the fibers in the coagulation process, the jet stretches were then corrected from the apparent values to the true values, and their effect on the cross-sectional morphology, internal structure, and orientation of the wet-spun PAN fibers was studied by optical microscopy, scanning electron microscopy, and X-ray diffraction, respectively. The results showed that jet stretch plays an important role in eliminating the adverse effects caused by the jet swell effect and affects the fiber structure; PAN fibers of uniform denier, dense and homogenous structure, and high orientation can only be obtained at a suitable jet stretch. [ABSTRACT FROM PUBLISHER]

Two new supramolecular compounds, [(H4aobtc)0.5(H2O)0.5] (1) and [(H3aobtc)(H2bipy)0.5] (2) (H4aobtc = azoxybenzene-3,3′,4,4′-tetracarboxylic acid), were synthesized and characterized. Compound 1 has a complicated three-dimensional hydrogen bonding network with 4-connected {33.62.7} topology. Compound 2 also shows a three-dimensional supramolecular motif with hexagonal topology. The result indicated that hydrogen bonding interactions from different molecular synthons take important roles in the formation of supramolecular architectures. [ABSTRACT FROM PUBLISHER]

A novel hyperbranched polyphosphate bisphenol-S ester (HPPES) flame retardant was prepared. The structure and thermal stability of the product were characterized. Polyamide 6 (PA6), HPPES and melamine pyrophosphate (MPP) were used to prepare flame retardant PA6 (FR-PA6) through melt blending. Limiting oxygen index (LOI), UL-94 vertical burning methods, thermogravimetric analysis (TGA), X-ray photoelectron spectroscope (XPS) and scanning electron microscope (SEM) were used to investigate the combustion properties, thermal degradation behaviours and char forming of FR-PA6. The results showed that synergistic effect between HPPES and MPP was present, which enhanced the char forming and flame retardance of PA6. [ABSTRACT FROM AUTHOR]

A polyoxoniobate, [Cu(en)2]4{[Nb6O19H2]K(H2O)5}2 ⋅ (H2en) ⋅ 17H2O (en = ethylenediamine) (1), has been synthesized and characterized by elemental analysis, IR, XPS, TGA, and single-crystal X-ray diffraction. Compound 1 crystallizes in the triclinic system, space group P1, with a = 12.3533(16) Å, b = 12.7188(16) Å, c = 29.626(4) Å, α = 93.235(2)°, β = 96.094(1)°, γ = 106.098(2)°, V = 4429.0(10) Å3, Z = 2. The polyoxoanion is composed of a Lindqvist-type [Nb6O19H2]6- dimer bi-bridged via two K+. K+ is 10-coordinate with 10 oxygens, three from one [Nb6O19H2]6-, one from a terminal oxygen of another [Nb6O19H2]6- moiety, and the other six from water molecule. Adjacent dimeric polyoxoanions are linked to form an infinite 1-D chain via O-H ··· O hydrogen-bonding interactions which exist between the two water trimers and the dimeric polyoxoanions. [ABSTRACT FROM AUTHOR]

The Tibet Class and the Xinjiang Class in the interior regions are typical models of cross-cultural education. Studies targeted at the difficulties encountered by ethnic minority students during their interior-region (neidi) cross-cultural studies and the implementation of effective countermeasures to overcome such difficulties are urgently required to bring greater efficiency to the special ethnic minority education policy of managing schools in the interior regions. [ABSTRACT FROM AUTHOR]

The interactions between rutin and trypsin were investigated by UV-Vis absorption, CD, fluorescence, resonance light-scattering spectra, synchronous fluorescence, and three-dimensional fluorescence spectra techniques under physiological pH 7.40. Rutin effectively quenched the intrinsic fluorescence of trypsin via static quenching. The enthalpy change and entropy change were estimated to be -8.23 kJ·mol-1 and 53.66 J·mol-1·K-1 according to the van't Hoff equation. The process of binding rutin to trypsin was a spontaneous molecular interaction procedure. This result indicates that hydrophobic and electrostatic interactions played a major role in stabilizing the complex. The conformation of trypsin was discussed by CD, synchronous, and three-dimensional fluorescence techniques. [ABSTRACT FROM AUTHOR]

The protein and mRNA expression of focal adhesion plaque associated cytoskeletons, including talin, vinculin, paxillin, and tensin, was studied using immunofluorescence in combination with confocal laser scanning microscopy and fluorescent quantitative polymerase chain reaction in 41 matched samples of human normal colorectal mucosae, primary colorectal adenocarcinomas, and 19 separate lymph node metastases. All specimens showed expression. The results showed talin, vinculin, tensin, and paxillin expression were correlated with carcinogenesis, invasion, and metastasis of colorectal carcinoma (CRC). Talin, vinculin, and tensin underwent downregulation while paxillin went up. So these cytoskeletons may play bidirectional regulating roles during the progression of CRC. [ABSTRACT FROM AUTHOR]

A series of thiosemicarbazone derivatives of benzo-15-crown-5 were synthesized efficiently at room temperature using hydrogenchloride acid (HCl) as catalyst. Their anion recognition properties of a, b and c were studied, the result show they exhibit highly selective binding and sensing of F-, MeCO2- and n-C3H7CO2- in CH3CN (F- > n-C3H7CO2- > MeCO2- > > Cl-, Br- and I-). Especially receptor c shows different UV-Vis spectrum of F- from MeCO2-and C3H7CO2-, in addition to the color of the solution change from colorless to yellow upon the addition of F-, these two points make it suitable to be used as colorimetric anion sensor to identify fluoride anion from other halide anions and carboxylate anions by naked-eye. The connection between receptor and anion is by hydrogen bonding interactions, the binding ratio is 1:1, which have been confirmed by UV-vis inspection spectra in CH3CN and 1HMR in DMSO-d6. [ABSTRACT FROM AUTHOR]

Two novel chiral fluorescence calix[4]arenes functionalized at the lower rim with diphenylethylenediamine and thiourea units were synthesized and examined for their enantioselective recognition abilities by the fluorescence and 1H NMR spectra in DMSO. The results indicate that 1 and 2 both formed a 1:1 complex with amino alcohol and exhibit good enantioselective fluorescent responses for phenylglycinol (receptor 1 KL/KD = 4.85, ΔΔG0 = - 3.90 kJ mol- 1). [ABSTRACT FROM AUTHOR]

A series of novel 6-(aroxymethyl)-2-aryl-6,7-dihydropyrazolo[5,1-c][1,4] oxazin-4-one derivatives was synthesized from ethyl 3-aryl-1H-pyrazole-5-carboxylate and 2-aryloxymethylepoxide by a microwave-assisted, one-step method in good yields. The microwave-assisted reaction of ethyl 3-aryl-1H-pyrazole-5-carboxylate and 2-aryloxymethylepoxide proceeds with higher regioselectivity and is more economical and environmentally friendly in contrast to the normal intramolecular esterification route. A tandem mechanism of the reaction was proposed. [ABSTRACT FROM AUTHOR]

The reaction of 1,3-bis(pyridyl-4-ylthio)propan-2-one with Cu(ClO4)2 · 6H2O gave a new complex {[Cu2(4PDS)2(ox)(H2O)4](ClO4)2}n (4PDS = 4,4'-dipyridyldisulfide, ox = oxalate), with 4PDS and ox being created by the Cu(II)-assisted oxidation of 1,3-bis(pyridyl-4-ylthio)propan-2-one. The complex determined by X-ray crystallography is a 1D polymer, in which metallacycles formed by two 4PDS and two Cu(II) ions are further bridged through ox anions. It crystallizes in the orthorhombic system, space group Fddd, with lattice parameters a = 15.106(2), b = 23.667(4), c = 27.637(3) Å and Z = 8. [ABSTRACT FROM AUTHOR]

Phase behavior of aqueous mixed surfactants, 1,3‐propanediyl bis(dodecyl dimethylammonium bromide) and sodium dodecyl sulfonate, has been studied at 318.15 K. The influence of added sodium halides (NaF, NaCl, and NaBr) has been investigated. For those systems studied, only one aqueous two‐phase region is formed in which cationic gemini surfactant is in excess. Different salt effects on the densities of the concentrated phases in aqueous two‐phase systems were observed for the three sodium halides. Density experiments indicate that contributions of various ions and water to the density of the solutions are near additive. Whether the concentrated phases in aqueous two‐phase systems are the bottom phases with higher densities or not are dependent on the different counterion binding ability and on the different contribution to the density of the three halides. [ABSTRACT FROM AUTHOR]

Yimeng scorpion is a specific geographical indication breed of Yimeng Mountain area in China. The complete mitochondrial genome sequence of Yimeng scorpion was determined for the first time (Accession number MN597087). It is mitochondrial genome (14,840 bp) contains 13 protein-coding genes, 21tRNA genes, 2 ribosomal RNA genes and one large non-coding region (a possible control region). Moreover, tRNA-ASP-loss was observed from the Yimeng scorpion mitochondrial genome. The mitochondrial genome sequence of the Yimeng scorpion enriches data resource for further research on genetic mechanism and classification. [ABSTRACT FROM AUTHOR]

In this study, the effect of suppression on phosphate liberation from eutrophic lake sediment by using fly ash and ordinary Portland cement (OPC) was investigated by small scale experiment. A system including sediment, lake water, and several kinds of capping materials was designed to clarify the suppression of phosphate liberation from sediment under the anaerobic condition. The suppression efficiencies of fly ash, OPC and glass bead used as control material were also determined, and these effects were discussed. The suppression efficiency of glass bead was 44.4%, and those of fly ash and OPC were 84.4%, 94.9%, respectively. The suppression by fly ash and OPC was mainly carried out by the adsorption effect, in addition to the covering effect. The suppression efficiency depended on the amounts of the material used, and about 90% of liberated phosphate was suppressed by fly ash of 10.0 Kg m -2 , and OPC of 6.0 Kg m -2 . The concentrations of heavy metals, such as mercury, cadmium, lead, copper, zinc, chromium, silver, arsenic and nickel, in fly ash and OPC were lower than those in the environmental materials. And it was considered that the concentrations of heavy metals in fly ash and OPC were too low to influence the ecosystem in natural water region. [ABSTRACT FROM AUTHOR]

Rana zhenhaiensis is a species of frog within the family Ranidae. In this study, its complete mitochondrial genome was characterized by high-throughput sequencing technology. It is 19,205 bp long with an overall AT content of 55.2% and includes 13 protein-coding genes (PCGs), 22 tRNA genes, 2 rRNA genes, and 1 control region. Besides, a 26-bp-long origin of L-strand replication (OL) is present between tRNA-Asn and tRNA-Cys. Our findings will be useful for the detailed study of mitogenome evolution and the phylogenetic relationships of the genus Rana and related taxa. [ABSTRACT FROM AUTHOR]

9a-(3-Azabicyclo[3,3,1]nonanyl)-2'-cyclopentyl-2'-hydroxy-2'-phenylacetate (1) was synthesized and its enantiomers were obtained by the optical resolution of racemates with the chiral host N- p -toluenesulfonylglutamic acid. Optical pure 1 was also effective diastereoselective synthesized using benzaldehye as steric hindrance agent from the chiral starting material, ( S ) or ( R )-mandelic acid. The structure of the title compound was first elucidated by X-ray analysis. [ABSTRACT FROM AUTHOR]

The problem of boundary feedback stabilization of rotating Timoshenko beam, arising from control of flexible robot arms, is studied in this paper. First, under gain adaptive direct strain feedback controls, a counterexample is given to show that the corresponding closed loop system is not asymptotically stable, which is contrary to traditional conjecture. The counterexample given in this paper also exemplifies an interesting result: certain two two-order linear partial differential equations with five homogeneous boundary conditions have non-trivial solutions. Then, with an additional boundary feedback control, the related energy of the closed loop system is proved to be strongly stable, or more precisely, the configuration of the beam can be exponentially stabilized with some suitable non-linear boundary feedback controls with adaptive gain. [ABSTRACT FROM AUTHOR]

Thee fabrication is reported of a simple, compact, and stable refractive index (RI)-independent temperature sensor based on a soft glass fiber (SGF) interferometer. Because the SGF has a high thermal expansion coefficient and a high RI, it is sensitive to temperature change but not sensitive to the RI change of liquids with lower RI. It thus can be used to detect the temperature change of aqueous solutions accurately. As an example, a temperature sensor with a temperature sensitivity of ∼17 pm/°C and a negligible RI sensitivity of only about −1 nm/RIU (RI unit) in the range 1.32–1.43 is demonstrated. In addition, our SGF interferometer has potential applications and advantages in detecting liquids such as liquid crystals with higher RI. [ABSTRACT FROM PUBLISHER]

In this paper, the complete mitochondrial (mt) genome ofSipunculus nuduscollected from the coast of southeast China was determined. The complete mt genome was 15,376 bp in length, including 13 protein-coding genes, 2 rRNA genes, 23 tRNA genes, and a putative control region (CR). The overall base composition of the H-strand is 29.25% A, 28.78% T, 27.19% C, and 14.78% G, with an AT content of 58.03%. The mt DNA of ChineseS. nudusshared 73.6% and 60.2% identities with that of FrenchS. nudus(GenBank accession number: FJ42,2961) and ChinesePhascolosoma esculenta(GenBank accession number: EF58,3817), respectively. [ABSTRACT FROM AUTHOR]

Dynamic response of a dual-frequency liquid crystal (DFLC) based near infrared phase modulator is investigated through numerical simulations and experiments. The relationships between the optical response times and various voltage driving conditions are studied. An optical phase retarder operating at 1.55 μm wavelength is demonstrated by using our homemade high figure-of-merit DFLC mixture. To improve the response time, both dual- frequency addressing and high voltage overdrive methods are employed. The obtained optical rising and decay times are reduced to less than 0.5 ms for a 2π phase change. The optical transition curves simulated with finite element method show good agreement with our experimental results. [ABSTRACT FROM AUTHOR]