bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of the toxicity of 17 essential oils against Choristoneura rosaceana (Lepidoptera: Tortricidae) and Trichoplusia ni (Lepidoptera: Noctuidae)
Authors: Machial Cristina M , Shikano Ikkei , Smirle Michael , Bradbury Roderick , Isman Murray B 
Published: July 2010

AbstractBACKGROUND: The obliquebanded leafroller, Choristoneura rosaceana Harris, and the cabbage looper, Trichoplusia ni Hübner, are serious fruit and vegetable pests requiring multiple insecticide applications per year. To reduce non‐target exposure to hazardous insecticides and to curb resistance development, alternative controls are required. Accordingly, a selection of 17 essential oils was screened against both lepidopteran pests, and the influence of azinphos‐methyl resistance on essential oil toxicity to C. rosaceana was studied.RESULTS: Of the 17 essential oils screened, patchouli oil (Pogostemon cablin Benth.) and thyme oil (Thymus vulgaris L.) were selected for further testing against C. rosaceana, whereas patchouli oil, garlic oil (Allium sativum L.) and lemongrass oil (Cymopogon nardus L.) were selected for further testing against T. ni. LC50 and LD50 values confirmed that patchouli oil was the most toxic to C. rosaceana larvae, with LC50 = 2.8 µL mL−1 and LD50 = 8.0 µg insect−1. Garlic oil was the most toxic oil to T. ni larvae with LC50 = 3.3 µL mL−1 and LD50 = 22.7 µg insect−1, followed by patchouli oil and lemongrass oil. Azinphos‐methyl‐resistant leafrollers were 1.5‐fold more tolerant to patchouli oil and 2.0‐fold more tolerant to thyme oil.CONCLUSIONS: Based on these results, patchouli oil and other essential oils have sufficient efficacy to be considered as components of an essential oil‐based insecticide that targets these lepidopteran pests. Copyright © 2010 Crown in the right of Canada. Published by John Wiley & Sons, Ltd
Multifunctionalised benzoxazinones in the systems Oryza sativa–Echinochloa crus‐galli and Triticum aestivum–Avena fatua as natural‐product‐based herbicide leads
Authors: Macías Francisco A , Chinchilla Nuria , Arroyo Elena , Varela Rosa M , Molinillo José MG , Marín David 
Published: July 2010

AbstractBACKGROUND: Fifteen novel derivatives of D‐DIBOA, including aromatic ring modifications and the addition of side chains in positions C‐2 and N‐4, had previously been synthesised and their phytotoxicity on standard target species (STS) evaluated. This strategy combined steric, electronic, solubility and lipophilicity requirements to achieve the maximum phytotoxic activity. An evaluation of the bioactivity of these compounds on the systems Oryza sativa–Echinochloa crus‐galli and Triticum aestivum–Avena fatua is reported here.RESULTS: All compounds showed inhibition profiles on the two species Echinochloa crus‐galli (L.) Beauv. and Avena fatua L. The most marked effects were caused by 6F‐4Pr‐D‐DIBOA, 6F‐4Val‐D‐DIBOA, 6Cl‐4Pr‐D‐DIBOA and 6Cl‐4Val‐D‐DIBOA. The IC50 values for the systems Echinochloa crus‐galli–Oryza sativa and Avena fatua–Triticum aestivum for all compounds were compared. The compound that showed the greatest selectivity for the system Echinochloa crus‐galli–Oryza sativa was 8Cl‐4Pr‐D‐DIBOA, which was 15 times more selective than the commercial herbicide propanil (Cotanil‐35). With regard to the system Avena fatua–Triticum aestivum, the compounds that showed the highest selectivities were 8Cl‐4Val‐D‐DIBOA and 6F‐4Pr‐D‐DIBOA. The results obtained for 6F‐4Pr‐D‐DIBOA are of great interest because of the high phytotoxicity to Avena fatua (IC50 = 6 µM, r2 = 0.9616).CONCLUSION: The in vitro phytotoxicity profiles and selectivities shown by the compounds described here make them candidates for higher‐level studies. 8Cl‐4Pr‐D‐DIBOA for the system Echinochloa crus‐galli‐Oryza sativa and 6F‐4Pr‐D‐DIBOA for Avena fatua‐Triticum aestivum were the most interesting compounds. Copyright © 2010 Society of Chemical Industry
Electronic and thermal transport properties of Mg2Sn crystals containing finely dispersed eutectic structures
Authors: Chen H. Y. , Savvides N. , Dasgupta T. , Stiewe C. , Mueller E. 
Published: July 2010

AbstractThe electronic and thermal transport properties of Mg2Sn crystals prepared by radio‐frequency (RF) induction melting, were investigated in the temperature range 10−700 K to study the effect of adding excess silver to the melt on the microstructure and thermoelectric properties. As the Ag‐content increases the amount of silver incorporated at doping sites tends to saturate so that the carrier concentration increases asymptotically to 6.3 × 1019 cm−3. The excess amount of silver reacts with magnesium to form a fine MgAg + Mg2Sn eutectic structure. The temperature dependence of the carrier mobility varies from ∼T−1.5 for the heavily doped samples in the extrinsic range to ∼T−2.8 for the undoped sample in the intrinsic range. From electrical conductivity and Hall measurements on the undoped samples we find the energy gap to be 0.36−0.38 eV. Doped samples show broad Seebeck peaks of 150−210 µV K−1 at T = 350−550 K. The thermal conductivity decreases sharply as the addition of Ag is increased, and reaches a minimum value of κ = 3.4 W m−1 K−1 at 450 − 500 K for the doped sample containing a uniformly distributed eutectic phase, leading to a maximum figure of merit ZTmax = 0.30.
Examples for the integration of self‐organized nanowires for functional devices by a fracture approach
Authors: Gedamu Dawit , Jebril Seid , Schuchardt Arnim , Elbahri Mady , Wille Sebastian , Kumar Mishra Yogendra , Adelung Rainer 
Published: July 2010

AbstractSimple and versatile methods to form nanowires on microchips are of interest for fundamental research and hold the potentials for an industrial fabrication. In this review article, one of these methods based on thin film fracture will be described introducing the experimental parameters and the potential for research. The advantages of the utilization of thin film cracks as a template for the nanowire formation are numerous: nanowire generation ready with contacts, a wide ranging freedom in the choice of materials, influence on the internal structure of the nanowire or the precise positioning on a microchip. A detailed discussion about the fabrication steps and some preliminary experiments revealing the possibilities of the fracture approach will be given for obtained metallic, semiconducting and anodized nanowires. In contrast to their macroscopic counterparts, the conductivity through the nanowires is entirely different. The influence of the surrounding gas atmospheres and the application of electrical fields demonstrate the applicability of these nanowires fabricated by using such a fracture approach.magnified image
Perspective scanning electron microscopy micrograph of Au nanowires fabricated by thin film fracture approach between Au contact lines. The wires form a zigzag pattern on the thermally oxidized layer substrate on a silicon chip.
Polarization switching of the optical gain in semipolar InGaN quantum wells
Authors: Scheibenzuber W. G. , Schwarz U. T. 
Published: July 2010

AbstractWe investigate the influence of polarization switching on the optical gain of semipolar InGaN quantum wells (QWs) depending on indium content and charge carrier concentration using self‐consistent 6 × 6 k·p‐band structure calculations. The semipolar planes considered here are the $(11\bar {2}2)$‐ and the $(20\bar {2}1)$‐plane. In contrast to the $(20\bar {2}1)$‐plane, the dominant polarization of the optical gain in a QW on the $(11\bar {2}2)$‐plane can depend on both the indium content and the charge carrier concentration, as reported from experiments. These effects are explained by a detailed analysis of the wave function composition of the topmost valence bands in a semipolar QW.
Frequency dependent power efficiency of a nanostructured surface plasmon coupler
Authors: Ghoshal Amitabh , Kik Pieter G. 
Published: July 2010

AbstractSurface plasmon (SP) excitation on an extended thin metal film via a miniature nanoparticle‐enhanced grating coupler is studied experimentally using leakage radiation spectroscopy. A universally applicable method for determining the efficiency of free‐space SP excitation is developed, and the efficiency of the coupler is determined. Two distinct grating excitation modes are observed, as well as a particle‐mediated excitation mode. The maximum observed coupling efficiency of the structure was approximately 3.5% at 615 nm and 670 nm, corresponding to the two grating modes of the structure. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
New features on the fragmentation patterns of homoisoflavonoids in Ophiopogon japonicus by high‐performance liquid chromatography/diode‐array detection/electrospray ionization with multi‐stage tandem mass spectrometry
Authors: Qi Jin , Xu Deran , Zhou Yi‐Feng , Qin Min‐Jian , Yu Bo‐Yang 
Published: July 2010

AbstractHomoisoflavonoids, a special class of flavonoids, are mainly distributed in the Liliaceae family and have various biological activities. Previously, very little research has been reported on the gas‐phase fragmentation patterns of homoisoflavonoids by electrospray ionization mass spectrometry. In this paper, we report the use of high‐performance liquid chromatography with a diode‐array detector (HPLC‐DAD) and electrospray ionization multi‐stage tandem mass spectrometry (ESI‐MSn) to study the fragmentation behavior of 11 homoisoflavonoid standards and to analyze homoisoflavonoids in Ophiopogon japonicus. In total, 28 homoisoflavonoids (including seven novel constituents) were characterized. The deprotonated [MH]− molecules of the homoisoflavonoids containing a saturated C2C3 bond afforded the A or B product ion (base peak) according to whether the B‐ring was substituted with a hydroxyl group. For the homoisoflavonoids containing a C‐2C‐3 double bond, the product ions (A or C ion) were created from the precursor [MH]− ion as the base peak when the B‐ring was substituted with a hydroxyl group. The homoisoflavonoids carrying a formyl group in the A‐ring readily eliminated one molecule of CO to form the product ion [M + HCO]− (base peak) irrespective whether the C‐2C‐3 bond was saturated or not. This product ion afforded the [MHCOB‐ringCH2 + H]− ion by cleavage of the C3C9 bond. This latter product ion always appeared in tandem mass (MS/MS) spectra of type I homoisoflavonoids. The common features of flavonoids observed during the gas‐phase fragmentation mechanisms were the loss of the following groups: 15 Da (CH3), 18 Da (H2O), 28 Da (CO), 44 Da (CO2) and 46 Da (CH2O2). A retro‐Diels‐Alder (RDA)‐like cleavage was also observed for the homoisoflavonoids. The different gas‐phase fragmentation routes were characterized for the deprotonated molecules obtained from the various homoisoflavonoids and collision‐induced dissociation (CID) fragmentation differences were noted for the different locations of the various substituents. In conclusion, we can say that this study allowed us to structurally elucidate and identify homoisoflavonoids distributed in related plants and their complex prescriptions. Copyright © 2010 John Wiley & Sons, Ltd.
Studies on the non‐covalent interactions between cyclodextrins and aryl alkanol piperazine derivatives by mass spectrometry and fluorescence spectroscopy
Authors: Chu Yan‐Qiu , Dai Xin‐Hua , Jiang Dan , Jiang Gong‐Yu , Fang Xiang , Ding Chuan‐Fan 
Published: July 2010

AbstractThe non‐covalent complexes of α‐ and β‐cyclodextrins (α‐, β‐CDs) with two aryl alkanol piperazine derivatives (Pipe I and Pipe II) have been studied by electrospray ionization mass spectrometry (ESI‐MS) and fluorescence spectroscopy. The ESI‐MS experimental results demonstrated that Pipe I can conjugate to β‐CD and form 1:1 or 1:2 stoichiometric non‐covalent complexes, and Pipe II can only form 1:1 complexes with α‐ or β‐CD. Fluorescence spectra indicated that the fluorescence intensities of Pipe I and Pipe II can be enhanced by increasing the content of β‐CD. The mass spectrometric titration experiments showed that the dissociation constants Kd1 were 5.77 and 9.52 × 10−4 mol L−1 for the complexes of α‐CD with Pipe I and Pipe II, respectively, revealing that the binding of α‐CD‐Pipe I was stronger than α‐CD‐Pipe II. The Kd1 and Kd2 values were 9.81 × 10−4 mol L−1 and 1.11 × 10−7 (mol L−1)2 for 1:1 and 1:2 complexes of Pipe I with β‐CD, respectively. The Kd values obtained from fluorescence spectroscopy were in agreement with those from ESI‐MS titration. Copyright © 2010 John Wiley & Sons, Ltd.
Chemical dephosphorylation for identification of multiply phosphorylated peptides and phosphorylation site determination
Authors: Kyono Yutaka , Sugiyama Naoyuki , Tomita Masaru , Ishihama Yasushi 
Published: July 2010

AbstractWe have developed a novel strategy to improve the efficiency of identification of multiply phosphorylated peptides isolated by hydroxy acid modified metal oxide chromatography (HAMMOC). This strategy consists of alkali‐induced chemical dephosphorylation (beta‐elimination reaction) of phosphopeptides isolated by HAMMOC prior to analysis by liquid chromatography/mass spectrometry (LC/MS). This approach identified 1.9‐fold more multiply phosphorylated peptides than the conventional approach without beta‐elimination from a digested mixture of three standard phosphoproteins. In addition, the accuracy of phosphorylation site determination in synthetic phosphopeptides was significantly improved. Finally, we applied this approach to a cell lysate. By combining this dephosphorylation approach with the conventional approach, we successfully identified 1649 unique phosphopeptides, including 325 multiply phosphorylated phosphopeptides, from 200 µg of cultured Arabidopsis cells. These results indicate that chemical dephosphorylation prior to LC/MS analysis increases the efficiency of identification of multiply phosphorylated peptides, as well as the accuracy of phosphorylation site determination. Copyright © 2010 John Wiley & Sons, Ltd.
An online method combining a Gasbench II with continuous flow isotope ratio mass spectrometry to determine the content and isotopic compositions of minor amounts of carbonate in silicate rocks
Authors: Zha Xiang‐Ping , Zhao Yan‐Yan , Zheng Yong‐Fei 
Published: July 2010

AbstractAn online method using continuous flow isotope ratio mass spectrometry (CF‐IRMS) interfaced with a Gasbench II device was established to analyze carbon and oxygen isotopic compositions and to estimate the content of minor amounts of carbonate in silicate rocks. The mixtures of standard materials and high‐purity quartz are firstly used to calibrate different quantities of carbonate in silicates. The results suggest that the accuracy and precision of the online analysis are both better than those obtained using an offline method. There is a positive correlation between the carbonate weight and the Mass44 ion beam intensity (or peak area). When the weight of carbonate in the mixtures is greater than 70 µg (equal to ∼1800 mV Mass44 ion beam intensity), the δ13C and δ18O values of samples usually have accuracy and precision of ±0.1‰ and ±0.2‰ (1σ), respectively. If the weight is less than 70 µg, some limitations (e.g., not perfectly linear) are encountered that significantly reduce the accuracy and precision. The measured δ18O values are systematically lower than the true values by −0.3 to −0.7‰; the lower the carbonate content, the lower the measured δ18O value. For samples with lower carbonate content, the required phosphoric acid doses are higher and more oxygen isotope exchanges with the water in the phosphoric acid. To guarantee accurate results with high precision, multiple analyses of in‐house standards and an artificial MERCK sample with δ13C values from −35.58 to 1.61‰ and δ18O from 6.04 to 18.96‰ were analyzed simultaneously with the unknown sample. This enables correction of the measured raw data for the natural sample based on multiple‐point normalization. The results indicate that the method can be successfully applied to a range of natural rocks. Copyright © 2010 John Wiley & Sons, Ltd.
Fast trypsin digestion of proteins on a cross‐linked [Os(dmebpy)2Cl]+/2+‐derivatized copolymer of acrylamide and vinylimidazole column
Authors: Zhou Jie 
Published: July 2010

AbstractFast digestion of proteins was observed when they were loaded together with trypsin onto the cross‐linked [Os(dmebpy)2Cl]+/2+‐derivatized copolymer of acrylamide and vinylimidazole column. The insoluble Os‐complexed polymer particles were packed into an electrospray tip to monitor peptides eluted during loading, washing and elution periods with a mass spectrometer. The proteolytic cleavage of proteins was observed immediately when the mixture of trypsin and substrates in 0.2 mM ammonium bicarbonate 50:50 H2O/acetonitrile reached the column tip, and continued through the loading period. Some tryptic peptides were released from the column during the loading and following washing periods. The others still stayed on the column until the low pH elution buffer reached the column. If a protein was first loaded onto the column, no tryptic peptides of the protein were observed when trypsin was loaded later for the on‐column digestion. Only the autolysis peptides of trypsin were observed. On‐column digestion of 100 fmol myoglobin was successfully detected with a low sensitivity quadrupole mass spectrometer. A hybrid Os‐polymer/C18 column tip was constructed for the online trypsin digestion of proteins in the aqueous buffers and the following trapping and elution of peptides from the C18 column. The digestion of reduced and alkylated bovine serum albumin and human transferrin in 2.5 mM ammonium bicarbonate and 0.2 M urea buffer was observed on the column, with more peptide coverage than conventional 4 h in‐solution digestion at 37°C. Control experiments without the Os‐polymer in the column tip excluded the spontaneous in‐solution digestion of proteins in the short time window of buffer delivery onto the column, indirectly confirming the contribution of Os‐polymer on the fast trypsin digestion. Copyright © 2010 John Wiley & Sons, Ltd.
Hierarchical scheme for liquid chromatography/multi‐stage spectrometric identification of 3,4,5‐triacyl chlorogenic acids in green Robusta coffee beans
Authors: Jaiswal Rakesh , Kuhnert Nikolai 
Published: July 2010

AbstractLiquid chromatography/multi‐stage spectrometry (LC/MSn) (n = 2–4) has been used to detect and characterize in green Robusta coffee beans eight quantitatively minor triacyl chlorogenic acids with seven of them not previously reported in nature. These comprise 3,4,5‐tricaffeoylquinic acid (Mr 678); 3,5‐dicaffeoyl‐4‐feruloylquinic acid, 3‐feruloyl‐4,5‐dicaffeoylquinic acid and 3,4‐dicaffeoyl‐5‐feruloylquinic acid (Mr 692); 3‐caffeoyl‐4,5‐diferuloylquinic acid and 3,4‐diferuloyl‐5‐caffeoylquinic acid (Mr 706); and 3,4‐dicaffeoyl‐5‐sinapoylquinic acid and 3‐sinapoyl‐4,5‐dicaffeoylquinic acid (Mr 722). Structures have been assigned on the basis of LC/MSn patterns of fragmentation. A new hierarchical key for the identification of triacyl quinic acids is presented, based on previously established rules of fragmentation. Fifty‐two chlorogenic acids have now been characterized in green Robusta coffee beans. In this study five samples of green Robusta coffee beans and fifteen samples of Arabica coffee beans were analyzed with triacyl chlorogenic acids only found in Robusta coffee bean extracts. These triacyl chlorogenic acids could be considered as useful phytochemical markers for the identification of Robusta coffee beans. Copyright © 2010 John Wiley & Sons, Ltd.
The snake for visualizing and for counting clusters in multivariate data
Authors: Petrie Adam , Willemain Thomas R. 
Published: July 2010

AbstractWe introduce the ‘snake’, a new tool for the visualization and exploration of a multivariate dataset. The snake connects each data point along a single short path. Using techniques from the Traveling Salesman Problem (TSP), it is possible to find such a path in polynomial (nearly quadratic) computational time. A plot of the individual segment lengths versus their position along the path transforms the original multidimensional dataset into a one‐dimensional ‘time‐series’ of interpoint distances. The snake traces the local structure of a datacloud, so this visualization is most useful for detecting density fluctuations: regions of high density appear as many consecutive short segments, while regions of low density appear as many consecutive long segments. Dips in the time series reveal the presence of clustering and can be used to count the number of modes in the datacloud. We illustrate the technique on a variety of artificial and real‐world datasets. Copyright © 2010 Wiley Periodicals, Inc. Statistical Analysis and Data Mining 3: 236‐252, 2010
Two‐way Gaussian mixture models for high dimensional classification
Authors: Qiao Mu , Li Jia 
Published: July 2010

AbstractMixture discriminant analysis (MDA) has gained applications in a wide range of engineering and scientific fields. In this article, under the paradigm of MDA, we propose a two‐way Gaussian mixture model for classifying high dimensional data. This model regularizes the mixture component means by dividing variables into groups and then constraining the parameters for the variables in the same group to be identical. The grouping of the variables is not pre‐determined, but optimized as part of model estimation. A dimension reduction property for a two‐way mixture of distributions from a general exponential family is proved. Estimation methods for the two‐way Gaussian mixture with or without missing data are derived. Experiments on several real data sets show that the parsimonious two‐way mixture often outperforms a mixture model without variable grouping; and as a byproduct, significant dimension reduction is achieved. Copyright © 2010 Wiley Periodicals, Inc. Statistical Analysis and Data Mining 3: 259‐271, 2010
Adhesion of Ag atoms to In surface magic clusters on Si(111)‐7 × 7 studied by UHV‐TEM/STM
Authors: Tanaka Miyoko , Teraoka Atsushi , Shimojo Masayuki 
Published: July 2010

AbstractSurface magic clusters (SMCs) of In on Si(111)‐7 × 7 surfaces and adhesion of subsequently deposited Ag atoms to them, were observed and analyzed by scanning tunneling microscopy (STM), transmission electron microscopy (TEM) and electron energy loss spectroscopy (EELS). Formation of In SMCs on faulted halves of 7 × 7 unit cells was confirmed by both STM images and transmission diffraction patterns. By subsequent Ag deposition, adhesion of Ag atoms onto preexisting In SMCs was observed. Corresponding diffraction pattern suggests that Ag atoms captured in the In SMCs have characteristic atomic structure which is different from known Ag‐In alloy phase. The changes in EELS spectrum are also discussed. Copyright © 2010 John Wiley & Sons, Ltd.
Biocompatibility, Biodistribution, and Drug‐Delivery Efficiency of Mesoporous Silica Nanoparticles for Cancer Therapy in Animals
Authors: Lu Jie , Liong Monty , Li Zongxi , Zink Jeffrey I. , Tamanoi Fuyuhiko 
Published: July 2010

AbstractMesoporous silica nanoparticles (MSNs) are a promising material for drug delivery. In this Full Paper, MSNs are first shown to be well tolerated, as demonstrated by serological, hematological, and histopathological examinations of blood samples and mouse tissues after MSN injection. Biodistribution studies using human cancer xenografts are carried out with in vivo imaging and fluorescent microscopy imaging, as well as with inductively coupled plasma mass spectroscopy. The results show that MSNs preferentially accumulate in tumors. Finally, the drug‐delivery capability of MSNs is demonstrated by following tumor growth in mice treated with camptothecin‐loaded MSNs. These results indicate that MSNs are biocompatible, preferentially accumulate in tumors, and effectively deliver drugs to the tumors and suppress tumor growth.