bluuebunny/crossref_metadata_2025_split huggingface dataset:
One‐step production of CO‐ and CO2‐free hydrogen from biomass
Authors: Ishida Minoru , Otsuka Kiyoshi , Takenaka Sakae , Yamanaka Ichiro 
Published: February 2005

AbstractThe reaction between a biomass (cellulose, sucrose, glucose, starch, cotton, or Japanese paper) and NaOH in the presence of water vapor produced pure hydrogen without CO and CO2 at temperatures in the range 473–623K. The addition of Ni/Al2O3 or Rh/Al2O3 catalyst to cellulose enhanced the production of hydrogen at <573 K. The reaction between cellulose and NaOH can be written as: C6H10O5 + 12NaOH + H2O = 6Na2CO3 + 12H2. The reactivities of alkali metal hydroxides were: KOH > NaOH ≫ LiOH. Copyright © 2004 Society of Chemical Industry
Analysis of the kinetics of growth and lactic acid production for Lactobacillus helveticus growing on supplemented whey permeate
Authors: Amrane Abdeltif 
Published: February 2005

AbstractGrowth of Lactobacillus helveticus on supplemented whey permeate was divided into five phases: lag, exponential, deceleration, stationary and decline phases. Each phase was characterized by simple model kinetics. From this and by considering a partial association of lactic acid production with growth, with an additional term introduced to account for cessation of production when the carbon substrate became limiting, the lactic acid production was analytically deduced for each growth phase. For both growth and production data, on the whole culture, the calculated values were found to match experimental data. All the model parameters can be easily deduced from experimental data. The model allows therefore a fine analysis of growth and production kinetics. Copyright © 2005 Society of Chemical Industry
Hydrolysis of the amyloid β‐peptide (Aβ) 1–40 between Asp23–Val24 produces non‐aggregating fragments. An electrospray mass spectrometric study
Authors: Hosia Waltteri , Griffiths William J. , Johansson Jan 
Published: February 2005

AbstractThe aggregation of full‐length (residues 1–40) amyloid β‐peptide (Aβ) and fragments corresponding to residues 1–23 and 24–40 was studied by electrospray mass spectrometry, using gramicidin as a non‐aggregating reference. Following a lag period, Aβ(1–40) at 140 µM concentration aggregates with apparent first‐order kinetics. Under acidic conditions Aβ(1–40) undergoes spontaneous cleavage between Asp23–Val24 and to a lesser extent also at two other Asp–X motifs. Incubation in acidic H218O showed incorporation of 18O in fragment Aβ(1–23), confirming that the Asp23–Val24 peptide bond had been hydrolyzed. Incubation of synthetic Aβ(1–23) and Aβ(24–40) peptides with Aβ(1–40) showed that Aβ(24–40) remained in solution for several months, that Aβ(1–23) partly disappeared from solution, whereas Aβ(1–40) completely disappeared. Further, treatment of sedimentable aggregates formed after co‐incubation of the three peptides with hexafluoro‐2‐propanol or formic acid recovered the intensity of Aβ(1–40). These data support previous studies showing that the region of Aβ encompassing residues 16–24 is necessary for aggregation into amyloid fibrils. Copyright © 2005 John Wiley & Sons, Ltd.
Mass spectrometric analysis of head ganglia and neuroendocrine tissue of larval Galleria mellonella (Arthropoda, Insecta)
Authors: Huybrechts Jurgen , Verleyen Peter , Schoofs Liliane 
Published: February 2005

AbstractA brain–retrocerebral complex–subesophageal ganglion acidified methanolic extract of 100 larval Galleria mellonella (greater wax moth) was prepared for the isolation and identification of (neuro)peptides. To reduce sample complexity, the isolated peptides were roughly separated using a single, conventional chromatographic separation step. Subsequently, screening of these fractions with matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry in combination with nanoflow electrospray ionization quadrupole time‐of‐flight tandem mass spectrometry resulted in the identification of 12 lepidopteran peptides. None of these had been previously isolated or characterized within this species. VIFTPKLamide encoded by the diapause hormone–pheromone biosynthesis activating neuropeptide precursor was for the first time isolated and biochemically identified in a tissue extract, providing irrefutable evidence of its expression in larval nervous tissue. Another pentapeptide, AMVRFamide, with no resemblance to other lepidopteran peptides, was de novo sequenced and is most related to the neuropeptide F peptide family. Copyright © 2005 John Wiley & Sons, Ltd.
Model Reduction in Emulsion Polymerization Using Hybrid First Principles/Artificial Neural Networks Models, 2
Authors: Arzamendi Gurutze , d'Anjou Alicia , Graña Manuel , Leiza José R. , Asua José M. 
Published: February 2005

AbstractSummary: A “series” hybrid model based on material balances and artificial neural networks to predict the evolution of weight average molecular weight, $\overline M _{\rm w}$, in semicontinuous emulsion polymerization with long chain branching kinetics is presented. The core of the model is composed by two artificial neural networks (ANNs) that calculate polymerization rate, Rp, and instantaneous weight‐average molecular weight, $\overline M _{{\rm winst}}$ from reactor process variables. The subsequent integration of the material balances allowed to obtain the time evolution of conversion and $\overline M _{\rm w}$, along the polymerization process. The accuracy of the proposed model under a wide range of conditions was assessed. The low computer‐time load makes the hybrid model suitable for optimization strategies.Effect of the monomer feed rate on $\overline M _{{\rm winst}}$.imageEffect of the monomer feed rate on $\overline M _{{\rm winst}}$.
A reduced‐size two‐layer bandpass filter
Authors: Djaiz Azzeddine , Denidni Tayeb A. 
Published: February 2005

AbstractIn this paper, a new design for a reduced‐size two‐layer bandpass filter is introduced. This filter is built using four resonators placed in two stacked microstrip layers. In this structure, each layer contains two resonators, and the coupling between the resonators in the upper layer and those in the lower one is achieved via two rectangular slots etched in a common ground plane placed between the two layers. Using this design, the size of the proposed filter can be significantly reduced. A design is fabricated and the measured results are described. These measurements demonstrate excellent agreement with the computer‐simulated predictions. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 44: 512–515, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20683
Parallel‐coupled phase‐matched multiring optical filters
Authors: Schwelb Otto , Frigyes István 
Published: February 2005

AbstractA periodic bandpass filter that is based on the phase‐matching principle and consists of several parallel‐coupled microrings is presented. The rings are identical in size; the coupling coefficients are chosen to provide maximally flat or equal ripple passband. Simulated filter characteristics exhibit steep roll‐off and large stopband rejection. Expressions are given to estimate the passband insertion loss and the stopband rejection level. The effects of loss and fabrication tolerances is examined. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 44: 536–540, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20689
An improved optically controlled phase shifter on Si wafer
Authors: Li H. P. , Chan Kam Tai 
Published: February 2005

AbstractThe transmission characteristics of an improved optically controlled microstrip interdigital gap structure on a high‐resistivity silicon substrate are reported. When irradiated with an optically controlled power as low as 8 mw, a maximum signal‐phase change of 37° is obtained while the signal amplitude remains nearly constant. The proposed device can potentially be used as an optically controlled phase shifter. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 44: 540–541, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20690
Use of electromagnetic band‐gap materials for RCS reduction
Authors: Collardey S. , Tarot A‐C. , Pouliguen P. , Mahdjoubi K. 
Published: February 2005

AbstractMost applications of electromagnetic band gap (EBG) concern antenna radiation or electromagnetic filters. In this paper, a metallic EBG structure is designed for stealth applications. We show how this structure allows us to reduce the radar cross section (RCS) of targets. An application of this kind of MEBG is the design of a radome allowing the reduction of antenna RCS. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 44: 546–550, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20693
Direct noise characterization of microwave FET using 50Ω noise figure and Y‐parameter measurements
Authors: De Dominicis Marco , Giannini Franco , Limiti Ernesto , Serino Antonio 
Published: February 2005

AbstractA fast and accurate method to determine the noise parameters of microwave FETs, based on a new expression of the device noise figure as a function of the Y‐parameters and two equivalent noise temperatures, is presented. The method requires only the measured small‐signal parameters and 50Ω noise figure, thus avoiding the extraction of the small‐signal equivalent circuit. It is particularly suitable for noise characterization of coplanar devices. Good agreement with the results of more conventional methods is demonstrated in a wide frequency range. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 44: 565–569, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20698
Electromagnetic simulations of metallic materials using the mapped fourier PSTD algorithm
Authors: Gao Xiang , Mirotznik Mark S. , Prather Dennis W. 
Published: February 2005

AbstractPreviously, the regular Fourier pseudospectral time‐domain (PSTD) algorithm was recognized as mainly applicable to simulations of low‐contrast dielectric materials. In this paper, we discuss the difficulties in simulating high‐contrast and particularly metallic materials using the Fourier PSTD method. To overcome these difficulties, we use a nonuniform grid obtained from a specially designed mapping curve that can reduce the Gibbs phenomenon in the mapped space. The convergence property of this technique is then examined. We show dramatic improvements compared with regular Fourier PSTD and finite‐difference time‐domain (FDTD) methods on a uniform grid. As an example application, we apply our method to the modeling of the 2D scattering of a chrome‐projection lithography mask. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 44: 569–575, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20699
Enhanced microstrip coupled‐line bandpass filter by means of EBG structures on the middle layer for spurious suppression
Authors: Weng Min‐Hung , Huang Tsung‐Hui , Hung Cheng‐Yuan 
Published: February 2005

AbstractIn this paper, a microstrip parallel‐coupled bandpass filter based on electromagnetic bandgap (EBG) structures to achieve spurious suppression is presented. The EBG loops of the middle layer add an extra stopband‐rejection mode to the 2nd and 3rd harmonics of the filter with attenuation losses of over than −30 dB, without affecting the center frequency and insertion loss of the originally designed filter. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 44: 575–577, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20700
Mutual coupling in finite microstrip patch arrays
Authors: Xi Y. P. , Fang D. G. , Sun Y. X. , Chow Y. L. 
Published: February 2005

AbstractKnowledge of the mutual interaction between antenna elements is of great importance for the design of practical antenna arrays, especially for phased arrays and ultra‐low side‐lobe arrays. In this paper, to fully take into consideration the mutual coupling in an array environment, a mutual‐impedance formula based on synthetic asymptote and variable separation [1] is used in an existing correction procedure in order to speed up the computation for microstrip patch arrays. The simulation results show that the performance of the finite microstrip patch arrays can be successfully predicted. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 44: 577–581, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20701
NMR study of quinolizidine alkaloids: relative configurations, conformations
Authors: Le Phuong Mai , Martin Marie‐Thérèse , Van Hung Nguyen , Guénard Daniel , Sévenet Thierry , Platzer Nicole 
Published: February 2005

AbstractExtracts of fruits and leaves of Connarus paniculatus afford six quinolizidine alkaloids which were identified as piptanthine, 18‐epipiptanthine, ormosanine, homoormosanine, podopetaline (monohydrochloride) and homopodopetaline on the basis of high‐field NMR studies. 1D and 2D NMR experiments provide complete assignments of the 1H and 13C spectra. In conjunction with detection of nuclear Overhauser effects (NOESY), these results allow detailed structure characterization including determination of relative configurations for the chiral sites and conformational analysis. Exchange phenomena involving nitrogen inversion were detected. Copyright © 2005 John Wiley & Sons, Ltd.
Synthesis and second‐order nonlinear optical properties of multifunctional polysiloxanes with sulfonyl‐based chromophores
Authors: Hua Jianli , Li Zhen , Long Kai , Qin Jingui , Li Shaojun , Ye Cheng , Lu Zuhong 
Published: February 2005

AbstractTwo new polysiloxanes (P1 and P2) with a high density of sulfonyl‐based chromophores were prepared by a new two‐step method. Poly[methyl‐3‐(9‐carbazolyl)propyl siloxane] was partially formulated by the standard Vilsmeier reaction, and formyl groups of high reactivity were condensed with cyanoacetylated chromophores; this yielded polysiloxanes P1 and P2 in almost complete conversions. Their structures were verified with 1H NMR, IR, and ultraviolet–visible spectra. P1 and P2 exhibited good solubility in common organic solvents and were thermally stable. The maximum absorptions appeared at about 452 and 390 nm for P1 and P2, respectively, in tetrahydrofuran; they were blueshifted about 42 and 8 nm, respectively, in comparison with those of the corresponding chromophores with a nitro acceptor and resulted in a wider transparency window. The P1 values of the nonlinear optical coefficient (d33), measured by in situ second harmonic generation, was 16.2 pm/V. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1317–1324, 2005
Cationic organoiron polyelectrolyte three‐arm stars
Authors: Abd‐El‐Aziz Alaa S. , Carruthers Sarrah A. , Todd Erin K. , Afifi Tarek H. , Gavina Jennilee M. A. 
Published: February 2005

AbstractWith nucleophilic aromatic substitution and ester condensation reactions, several new first‐generation dendrimers and star‐shaped molecules containing cationic cyclopentadienyl iron moieties were prepared. Although the solubility of the organoiron star‐shaped molecules with ether bridges in polar solvents was found to decrease with an increase in the size of the molecule, the addition of ester linkages resulted in a sharp decrease in the solubility, regardless of the size. The thermal behavior of these molecules was examined with differential scanning calorimetry and thermogravimetric analysis. The glass‐transition temperatures (Tg's) of these star‐shaped molecules ranged from 123 to 170 °C. However, the addition of the ester functionality allowed for an increase in the Tg's to 151–194 °C. The star‐shaped molecules were thermally stable up to 200 °C, above which a loss of the cationic cyclopentadienyl iron moieties occurred. Degradation of the ester chains started at 321 °C, and degradation of the ether chains started at 408 °C. Electrochemical studies of the ether star‐shaped molecules showed a reduction of the 18‐electron iron centers to 19‐electron centers. This redox system was reversible at low temperatures, whereas it was irreversible at room temperature. Moreover, an increase in the number of metal moieties caused an overlap and broadening of the redox wave. Viscosity studies showed a polyelectrolyte effect for the organoiron star‐shaped molecules. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1382–1396, 2005
Economic and herbicide use impacts of glyphosate‐resistant crops
Authors: Gianessi Leonard P 
Published: February 2005

AbstractMore than 95% of United States maize, cotton, soybean and sugarbeet acres are treated with herbicides for weed control. These products are used to improve the economic profitability of crop production for farmers. Since their introduction in 1996, over 75 million acres of genetically engineered glyphosate‐resistant crops have been planted, making up 80% of soybean acres and 70% of cotton acres in the USA. These genetically engineered crops have been adopted by farmers because they are perceived to offer greater economic benefits than conventional crop and herbicide programs. The adoption of glyphosate‐resistant crops has saved US farmers $1.2 billion associated with the costs of conventional herbicide purchases, application, tillage and hand weeding. With the adoption of glyphosate‐resistant sugarbeets on currently planted sugarbeet acres, US growers could potentially save an additional $93 million. The adoption of glyphosate‐resistant crops by US agriculture has reduced herbicide use by 37.5 million lbs, although the adoption of glyphosate‐resistant sugarbeets would dampen this reduction by 1 million lbs. Copyright © 2005 Society of Chemical Industry
PERIODIC PEAKONS AND CALOGERO–FRANÇOISE FLOWS
Authors: Beals R. , Sattinger D. H. , Szmigielski J. 
Published: February 2005

It has long been known that a number of periodic completely integrable systems are associated to hyperelliptic curves, for which the Abel map linearizes the flow (at least in part). We show that this is true for a relatively recent such system: the periodic discrete reduction of the shallow water equation derived by Camassa and Holm. The associated spectral problem has the same form and evolves in the same way as the spectral problem for a family of finite-dimensional non-periodic Hamiltonian flows introduced by Calogero and Françoise. We adapt the Weyl function method used earlier by us to solve the peakon problem to give an explicit solution to both the periodic discrete Camassa–Holm system and the (non-periodic) Calogero–Françoise system in terms of theta functions. AMS 2000 Mathematics subject classification: Primary 35Q51; 37J35; 35Q53
Reduced response of insecticide-resistant aphids and attraction of parasitoids to aphid alarm pheromone; a potential fitness trade-off
Authors: Foster S.P. , Denholm I. , Thompson R. , Poppy G.M. , Powell W. 
Published: February 2005

AbstractResponse to the alarm pheromone, (E)-β-farnesene, produced by many species of aphids, was assessed in laboratory bioassays using an aphid pest, Myzus persicae (Sulzer), and its primary endoparasitoid, Diaeretiella rapae (McIntosh). This was done in three separate studies, the first investigating responses of a large number of M. persicae clones carrying different combinations of metabolic (carboxylesterase) and target site (kdr) insecticide resistance mechanisms, and the other two investigating the responses of young virgin female adult parasitoids. In M. persicae, both insecticide resistance mechanisms were associated with reduced repellence suggesting that each has a pleiotropic effect on aphid behaviour. In contrast, D. rapae females were attracted to the alarm pheromone source. The implications of this apparent fitness trade-off for the evolution and dynamics of insecticide resistance, and the potential for using beneficial insects to combat resistance development are discussed.
Analysis of spatial patterns at a geographical scale over north-western Europe from point-referenced aphid count data
Authors: Cocu N. , Conrad K. , Harrington R. , Rounsevell M.D.A. 
Published: February 2005

AbstractThe spatial analysis by distance indices (SADIE) technique was developed to evaluate the spatial pattern of point-referenced count data as well as the spatial association between two sets of data sharing the same point locations. This paper presents an analysis of spatial patterns in aphid count data and the association of these data with climate across north-west Europe. The paper tests the applicability of the technique to large geographical areas. Aggregation and cluster indices were calculated for the total annual abundance of the peach–potato aphid Myzus persicae (Sulzer) and for the annual mean rainfall and temperature at aphid monitoring sites. Association indices demonstrated the stability in time of aphid spatial structures and the correlation between aphid density and climate patterns. Groups of relatively large numbers of aphids, termed patches, and groups of relatively small numbers of aphids, termed gaps, were located and their mean size estimated. The aphid patterns were quite stable in time and the spatial patterns of temperature and rainfall were weakly associated with M. persicae annual abundance. Similarities were observed between the results of SADIE and those from the more widely used technique of spatial autocorrelation (SAC). However, the SADIE association index has the advantage of quantifying the possible associations between aphid data and the factors that determine population distribution. Thus, high temperature and low rainfall were identified as environmental factors that were positively associated with aphid abundance across north-west Europe.
The life cycle of Henneguya nuesslini Schuberg & Schröder, 1905 (Myxozoa) involves a triactinomyxon‐type actinospore
Authors: Kallert D M , Eszterbauer E , El‐Matbouli M , Erséus C , Haas W 
Published: February 2005

AbstractThe life cycle of the histozoic myxozoan parasite Henneguya nuesslini was investigated in two salmonid host species. Naïve brown trout, Salmo trutta, and brook trout, Salvelinus fontinalis, were experimentally infected in two trials by triactinomyxon type actinospores from naturally infected Tubifex tubifex. In exposed common carp, Cyprinus carpio, no myxospore production was detected. The parasite formed cysts with mature myxospores in the connective tissue of the fish 102 days post‐exposure. The morphology of both actinosporean and myxosporean stages was described by light microscopy and a 1417‐bp fragment of the 18S rDNA gene was sequenced. Sequence analysis confirmed the absolute congruence of the two developmental stages and assisted in determining species identity. Host range, tissue specificity and myxospore measurements provided sufficiently distinctive features to confirm species validity and were thus crucial for identification. The triactinomyxon spores had 16 secondary germ cells, unique dimensions, a very opaque sporoplasm matrix and three conspicuously protruding, pyriform polar capsules. This is the first record of a Henneguya sp. life cycle with a triactinomyxon‐type actinospore, which suggests a close relationship with the Myxobolus group and a polyphyletic origin of the genus Henneguya.