bluuebunny/crossref_metadata_2025_split huggingface dataset:
Photocontrol of Ca2+ complexation with an azacrown‐containing benzochromene
Authors: Ushakov E. N. , Nazarov V. B. , Fedorova O. A. , Gromov S. P. , Chebun'kova A. V. , Alfimov M. V. , Barigelletti F. 
Published: January 2005

AbstractThe new azacrown‐containing benzochromene 1a was synthesized in order to study the effect of its reversible photochromic reaction on complex formation with Ca2+ in acetonitrile. It was found that both the initial chromene 1a and its photoinduced merocyanine isomer 2a are able to form 1:1 complexes with Ca2+, in which the metal cation coordinates to the crown ether moiety. The complexation causes strong spectroscopic shifts and leads to an increase in the dark lifetime of 2a. The equilibrium constant for the 1:1 complexation decreases upon photoinduced ring‐opening reaction (log K = 4.9 and 4.1 for 1a and 2a, respectively). Copyright © 2003 John Wiley & Sons, Ltd.
Comparative actions of clomazone on β‐carotene levels and growth in rice (Oryza sativa) and watergrasses (Echinochloa spp)
Authors: TenBrook Patti L , Tjeerdema Ronald S 
Published: January 2005

AbstractSeedlings of rice, early watergrass (thiobencarb‐resistant and thiobencarb‐susceptible biotypes, R and S, respectively), and late watergrass (thiobencarb‐resistant and thiobencarb‐susceptible biotypes, R and S, respectively) were hydroponically exposed to clomazone at concentrations ranging from 0.08 to 7.9 µM. Whole‐plant growth (mg fresh wt) and β‐carotene concentrations (µg g−1 fresh wt) were measured after a 7‐day exposure period. For growth, the no observed effect concentrations (NOECs) were 7.9, 0.21, 0.21, 0.46 and 0.46 µM clomazone for rice, early watergrass (R), early watergrass (S), late watergrass (R) and late watergrass (S), respectively, while the concentrations causing 25% inhibition in response (IC25) were 5.6 (±1.6), 0.46 (±0.06), 0.42 (±0.08), 0.92 (±0.45) and 0.79 (±0.08) µM clomazone, respectively. Clomazone inhibits β‐carotene synthesis via inhibition of the non‐mevalonate isoprenoid synthetic pathway. For assessment of clomazone effects, β‐carotene levels proved to be a more sensitive toxicological endpoint than growth. For rice, early watergrass (R), early watergrass (S), late watergrass (R) and late watergrass (S), the β‐carotene NOECs were 0.21, <0.08, <0.08, 0.08 and 0.46 µM clomazone respectively, while IC25 values were 0.42 (±0.26), 0.08 (±0.02), 0.08 (±0.02), 0.33 (±0.09) and 0.54 (±0.15) µM, respectively. No evidence was found that the thiobencarb‐resistance mechanisms present in early and late watergrasses impart resistance to clomazone. Due to similar sensitivity between rice and late watergrass, use of clomazone in rice culture will require the use of a safening technique. Copyright © 2005 Society of Chemical Industry
Technical performance of some commercial glyphosate‐resistant crops
Authors: Pline‐Srnic Wendy 
Published: January 2005

AbstractGlyphosate‐resistant (GR) crops have been sold commercially in the USA since 1996. The use of glyphosate alone or with conventional pre‐ and post‐emergence herbicides with different modes of action gives growers many options for affordable, safe, easy, effective wide‐spectrum weed control. Despite the overwhelming popularity of this technology, technical issues have surfaced from time to time as US growers adopt these crops for use on their farms. The types of concern raised by growers vary from year to year depending on the crop and the environment, but include perceptions of increased sensitivity to diseases, increased fruit abortion, reduced pollination efficiency, increased sensitivity to environmental stress, and differences in yield and agronomic characteristics between transgenic and sister conventional varieties. Although several glyphosate‐resistant crops are commercially available, maize, soybean and cotton constitute the largest cultivated acreage and have likewise been associated with the highest number of technical concerns. Because glyphosate is rapidly translocated to and accumulates in metabolic sink tissues, reproductive tissues and roots are particularly vulnerable. Increased sensitivity to glyphosate in reproductive tissues has been documented in both glyphosate‐resistant cotton and maize, and results in reduced pollen production and viability, or increased fruit abortion. Glyphosate treatments have the potential to affect relationships between the GR crop, plant pathogens, plant pests and symbiotic micro‐organisms, although management practices can also have a large impact. Despite these potential technical concerns, this technology remains popular, and is a highly useful tool for weed control in modern crop production. Copyright © 2005 Society of Chemical Industry
Herbicide resistance in transgenic plants with mammalian P450 monooxygenase genes
Authors: Inui Hideyuki , Ohkawa Hideo 
Published: January 2005

AbstractTransgenic potato and rice plants were generated by the introduction of human P450 species, CYP1A1, CYP2B6, CYP2C9 and CYP2C19, which metabolized a number of herbicides, insecticides and industrial chemicals. The transgenic potato plant T1977 co‐expressing CYP1A1, CYP2B6 and CYP2C19 genes showed remarkable cross‐resistance to several herbicides with different structures and modes of action due to metabolism of these herbicides by the P450 species expressed. The transgenic rice plant 2C9‐57R2 expressing CYP2C9 gene showed resistance to sulfonylureas, and the transgenic rice plant 2C19‐12R1 expressing CYP2C19 gene showed cross‐resistance to certain herbicides with different structures and modes of action. These transgenic plants appear to be useful for herbicide resistance as well as phytoremediation of environmental contaminants. Copyright © 2005 Society of Chemical Industry
Ultracold fermions with several flavors
Authors: Honerkamp C. 
Published: January 2005

AbstractUltracold atoms have attracted enormous interest recently, and Cooper pairing between fermionic alkali atoms may have been observed experimentally. Besides the demonstration of phenomena that we are acquainted with from solid state physics, ultracold atoms possibly exhibit interesting many‐body ground states that do not have straightforward counterparts in solid state physics. The hyperfine degree of freedom of the atoms in combination with optical lattices may allow for the approximate realization of fermionic SU(N) Hubbard models where N counts the number of trapped hyperfine states (‘flavors’). We analyze the ground states of this model on the two‐dimensional square lattice using one‐loop renormalization group and meanfield techniques. In the repulsive case for N > 6 and half band filling staggered flux order is found as the dominant instability, in agreement with the large‐N limit. In the attractive case and odd N a full Fermi surface coexists with a superfluid in the ground state. We describe how these unconventional paired states can be identified in the density response of the fermions. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ultracold atom superfluidity induced by the Feshbach resonance
Authors: Domański T. 
Published: January 2005

AbstractWe discuss the possible signatures of superfluidity induced by the Feshbach resonance in the ultracold gas of fermion atoms. Optically or magnetically trapped atoms such as 6Li or 40K are used in two hyperfine states where part of them is converted into the diatomic molecules. These fermion and boson entities get coupled in a presence of the external magnetic field. Eventually, at critical Tc, they simultaneously undergo transition to the superfluid state. Approaching this transition from above there appear various signatures manifesting a gradually emerging order parameter, but yet the long range coherence is not established due to the strong quantum fluctuations. Fermion atoms are characterized by the gapped excitation spectrum (pseudogap) up to temperature Tp (larger than Tc) while boson molecules exhibit collective features such as first sound showing up above a certain critical momentum q.crit (T) Upon lowering temperature to Tc this critical value shifts to zero and hence there appears the Goldstone mode signaling the symmetry broken superfluid state. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Anti‐allergic effect of Perilla frutescens and its active constituents
Authors: Makino Toshiaki , Furuta Yasuyuki , Wakushima Hannosuke , Fujii Hajime , Saito Ken‐ichi , Kano Yoshihiro 
Published: January 2005

AbstractThe leaves of Perilla frutescens Britton (Labiatae) are one of the most popular garnishes in Japan, used as an antidote for ﬁsh and crab meat allergy or as a food colorant. The present study was conducted to evaluate its anti‐allergic effect and to identify its active constituents using mice ear‐passive cutaneous anaphylaxis (PCA)‐reaction. 48 h after the cutaneous injection of anti‐ovalbumin serum into the ears of mice, ovalbumin and evansblue dye were intravenously injected. Perilla was extracted with boiling water, and intraperitoneally injected 15 min before ovalbumin‐treatment. Thirty min after ovalbumin‐treatment, the ears were removed and the colorant in the ear was colorimetrically quantitated. Perilla extract signiﬁcantly suppressed the PCA‐reaction, which was brought about by rosmarinic acid with a partial contribution from some macromolecular compounds. The anti‐allergic titer of rosmarinic acid was more effective than tranilast, which is a modern anti‐allergic drug. Perilla and rosmarinic acid are potentially promising agents for the treatment of allergic diseases. Copyright © 2003 John Wiley & Sons, Ltd.
Antinociceptive and antipyretic activities of Pongamia pinnata leaves
Authors: Srinivasan K. , Muruganandan S. , Lal J. , Chandra S. , Tandan S. K. , Raviprakash V. , Kumar D. 
Published: January 2005

AbstractIn the present study, the antinociceptive activity of a 70% ethanol extract of Pongamia pinnata leaves (PLE) was investigated in different models of pain in mice and rats. Further, PLE was also evaluated for its antipyretic activity in Brewer's yeast‐induced pyrexia in rats. Per os (p.o.) administration of the PLE (100–1000 mg/kg) produced signiﬁcant antinociceptive activity in the hotplate and tail ﬂick (central) as well as in acetic acid writhing and Randall‐Selitto (peripheral) nociceptive tests suggesting the involvement of both central and peripheral mechanisms in alleviating the pain response. In addition, PLE also exhibited a significant antipyretic response in Brewer's yeast‐induced pyrexia in rats. These results demonstrated that PLE possesses marked antinociceptive as well as antipyretic activities and thus scientiﬁcally validated its use in the treatment of pain and pyretic disorders. Copyright © 2003 John Wiley & Sons, Ltd.
Derivatisation for the characterisation of neutral oxosteroids by electrospray and matrix‐assisted laser desorption/ionisation tandem mass spectrometry: the Girard P derivative
Authors: Griffiths William J. , Liu Suya , Alvelius Gunvor , Sjövall Jan 
Published: January 2005

AbstractThe identification, quantification and localisation of steroids in biological fluids and tissues are subjects of considerable importance. Not only do steroids have classical hormonal properties via binding to nuclear receptors, they can also elicit cellular responses via interactions with other proteins. For mass spectrometric analysis, neutral steroids are not readily ionised by either electrospray (ES) or matrix‐assisted laser desorption/ionisation (MALDI). In this communication a derivatisation protocol is presented which allows for the rapid analysis of neutral oxosteroids by both ES and MALDI mass spectrometry. Neutral oxosteroids are derivatised to Girard P hydrazones. When analysed by tandem mass spectrometry the derivatised steroids fragment to give structurally informative spectra allowing subsequent steroid identification. The derivatisation method is simple, the reagents are commercially available, and reaction products are easily isolated from the reaction mixture. Analyte identification can be performed at the sub‐pg level. Copyright © 2003 John Wiley & Sons, Ltd.
Liquid chromatography/mass spectrometric analysis of explosives: RDX adduct ions
Authors: Gapeev Alexei , Sigman Michael , Yinon Jehuda 
Published: January 2005

AbstractIn liquid chromatography/mass spectrometry (LC/MS) of 1,3,5‐trinitro‐1,3,5‐triazacyclohexane (RDX), attachment of an anion to the analyte molecule is the major way of producing characteristic ions under electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) conditions. The formation of RDX cluster ions in LC/MS and the origin of the clustering agents have been studied. In order to determine whether the clustering anions originate from self‐decomposition of RDX in the source or from impurities in the mobile phase, isotopically labeled RDX (13C3‐RDX and 15N6‐RDX) and isotopically labeled glycolic acid, acetic acid, ammonium formate and formaldehyde have been used in order to establish the composition and formation route of RDX adduct ions produced in ESI and APCI sources. The results showed that, in ESI, self‐decomposition of RDX plays no role in adduct ion formation; rather, RDX clusters with formate, acetate, hydroxyacetate, and chloride anions present in the mobile phase as impurities at ppm levels. In APCI, part of the RDX molecules decompose yielding NO2− species which in turn cluster with a second RDX molecule producing abundant [M+NO2]− cluster ions. Copyright © 2003 John Wiley & Sons, Ltd.
Amount‐dependent isotopic fractionation during compound‐specific isotope analysis
Authors: Schmitt Jochen , Glaser Bruno , Zech Wolfgang 
Published: January 2005

AbstractThe performance of a gas chromatography‐combustion‐isotope ratio mass spectrometry system (GC‐C‐IRMS) with respect to the dependence of δ13C values on the amount of sample is presented. Particular attention is paid to the localization of the amount‐dependent isotopic fractionation within the system. Injection experiments with varying amounts of gases (CO2, n‐hexane, and toluene) revealed that neither the detector unit nor the combustion reactor, but rather the conditions in the split/splitless injector, contributed to this effect. Although optimization of injector parameters was performed and a reduction of this adverse effect from 3 to 1‰ was achieved, it was not possible to eliminate isotopic fractionation completely. Consequently, additional injector parameters have to be considered and adjusted to achieve injection conditions free of fractionation. For routine analysis of the compound‐specific δ13C analysis of different biomarkers in many environmental samples, perfect optimization may not always be reached. Therefore, in order to prevent systematic errors in the measured δ13C values due to different sample concentrations, it is suggested that correction for the remaining unknown amount‐dependent fractionation can be made by means of co‐analyzing standards of varying analyte concentrations and known δ13C values. Residual overall amount‐dependent isotope‐fractionation can thus be corrected mathematically. Copyright © 2003 John Wiley & Sons, Ltd.
Carotid and brachial intima-media thickness, arterial diameter and resistivity indices in aortic regurgitation
Authors: Kervancioglu S. , Davutoglu V. , Ozkur A. , Sezen Y. , Kervancioglu R. , Bayram M. M. 
Published: January 2005

Purpose: To evaluate signs of atherosclerosis in carotid and brachial arteries in patients with aortic regurgitation (AR). Material and Methods: The sonograms of 33 patients (24 M and 9 F, 16-67 years old) with pure AR and 20 control subjects (15 M and 5 F, 19-49 years old) were evaluated. Patients with AR and control subjects completed a questionnaire with SMART risk score based on pre-existing vascular disease and risk factors. AR patients and control subjects were assessed for intima-media thickness (IMT) of common carotid artery (CCA), IMT of brachial artery (BA), CCA diameter, and resistivity index (RI) of CCA and RI of internal carotid artery (ICA). Results: There was no significant difference in the cardiovascular risk score between the patients with AR and control subjects. All measured parameters were statistically significantly greater in AR patients than in control subjects with P values 0.0233 for CCA IMT, 0.0034 for BA IMT, 0.0429 for CCA diameter, &lt;0.0001 for CCA RI, and 0.0002 for ICA RI. Conclusion: AR is associated with signs generally considered to represent atherosclerosis, such as increased CCA and BA IMT, CCA diameter, and CCA and ICA RI.
The Dof Transcription Factor OBP3 Modulates Phytochrome and Cryptochrome Signaling in Arabidopsis
Authors: Ward Jason M. , Cufr Carie A. , Denzel Megan A. , Neff Michael M. 
Published: January 2005

AbstractPlants perceive subtle changes in light quality and quantity through a set of photoreceptors, including phytochromes and cryptochromes. Upon perception, these photoreceptors initiate signal transduction pathways leading to photomorphogenic changes in development. Using activation-tagging mutagenesis to identify novel light-signaling components, we have isolated a gain-of-function mutant, sob1-D (suppressor of phytochrome B-4 [phyB-4] dominant), which suppresses the long-hypocotyl phenotype of the phyB missense allele, phyB-4. The sob1-D mutant phenotype is caused by the overexpression of a Dof (DNA binding with one finger) transcription factor, OBF4 Binding Protein 3 (OBP3). A translational fusion between OBP3 and green fluorescent protein is nuclear localized in onion (Allium cepa) cells. Tissue-specific accumulation of an OBP3:OBP3-β-glucuronidase translational fusion is regulated by light in Arabidopsis thaliana. Hypocotyls of transgenic lines with reduced OBP3 expression are less responsive to red light. This aberrant phenotype in red light requires functional phyB, suggesting that OBP3 is a positive regulator of phyB-mediated inhibition of hypocotyl elongation. Furthermore, these partial-loss-of-function lines have larger cotyledons. This light-dependent cotyledon phenotype is most dramatic in blue light and requires functional cryptochrome 1 (cry1), indicating that OBP3 is a negative regulator of cry1-mediated cotyledon expansion. These results suggest a model where OBP3 is a component in both phyB and cry1 signaling pathways, acting as a positive and negative regulator, respectively. An alternate, though not mutually exclusive, model places OBP3 as a general inhibitor of tissue expansion with phyB and cry1, differentially modulating OBP3's role in this response.
Characterization of the Arabidopsisclb6Mutant Illustrates the Importance of Posttranscriptional Regulation of the Methyl-d-Erythritol 4-Phosphate Pathway
Authors: Guevara-García Arturo , San Román Carolina , Arroyo Analilia , Cortés María Elena , de la Luz Gutiérrez-Nava María , León Patricia 
Published: January 2005

AbstractThe biosynthesis of isopentenyl diphosphate and dimethylallyl diphosphate, the two building blocks for isoprenoid biosynthesis, occurs by two independent pathways in plants. The mevalonic pathway operates in the cytoplasm, and the methyl-d-erythritol 4-phosphate (MEP) pathway operates in plastids. Plastidic isoprenoids play essential roles in plant growth and development. Plants must regulate the biosynthesis of isoprenoids to fulfill metabolic requirements in specific tissues and developmental conditions. The regulatory events that modulate the plant MEP pathway are not well understood. In this article, we demonstrate that the CHLOROPLAST BIOGENESIS6 (CLB6) gene, previously shown to be required for chloroplast development, encodes 1-hydroxy-2-methyl-butenyl 4-diphosphate reductase, the last-acting enzyme of the MEP pathway. Comparative analysis of the expression levels of all MEP pathway gene transcripts and proteins in the clb6-1 mutant background revealed that posttranscriptional control modulates the levels of different proteins in this central pathway. Posttranscriptional regulation was also found during seedling development and during fosmidomycin inhibition of the pathway. Our results show that the first enzyme of the pathway, 1-deoxy-d-xylulose 5-phosphate synthase, is feedback regulated in response to the interruption of the flow of metabolites through the MEP pathway.
A Threshold Autoregressive Model for Wholesale Electricity Prices
Authors: Ricky Rambharat B. , Brockwell Anthony E. , Seppi Duane J. 
Published: January 2005

Summary
We introduce a discrete time model for electricity prices which accounts for both transitory spikes and temperature effects. The model allows for different rates of mean reversion: one for weather events, one around price jumps and another for the remainder of the process. We estimate the model by using a Markov chain Monte Carlo approach with 3 years of daily data from Allegheny County, Pennsylvania. We show that our model outperforms existing stochastic jump diffusion models for this data set. Results also demonstrate the importance of model parameters corresponding to both the temperature effect and the multilevel mean reversion rate.
Reactive oxygen species mediate abnormal contractile response to sympathetic nerve stimulation and noradrenaline in the vas deferens of chronically diabetic rats: effects of in vivo treatment with antioxidants
Authors: Güneş A. , Ceylan A. , Sarıoǧlu Y. , Stefek M. , Bauer V. , Karasu Ç. ,   The Antioxidants in Diabetes‐induced Complications (ADIC) Study Group
Published: January 2005

AbstractPrevious studies suggest that a link exists between increased oxidative stress and diabetic neuropathy. Moreover, antioxidants may protect neurones from the degenerative effects of reactive oxygen species. In our study, we used streptozotocin (STZ)‐diabetic rats in a 8‐month chronic diabetes model to study the effects of in vivo treatment with stobadine (ST), a pyridoindole antioxidant, and vitamin E. STZ‐diabetic rats were treated with ST (24.7 mg/kg/day), vitamin E (d,l‐alpha‐tocopheryl acetate, 400–500 IU/kg/day) or ST plus vitamin E through an intra‐oral catheter for a 8‐month period beginning 10 days after STZ injection. Blood glucose and HbA1c levels were increased in diabetic rats by about 400 and 100%, respectively. Antioxidant treatment significantly decreased haemoglobin glycosylation (P < 0.05). We also determined the effects of chronic diabetes on sympathetic neurotransmission by measuring the contractility of isolated vas deferens. Furthermore, we investigated contractions elicited by electrical field stimulation (EFS) (1–64 Hz) which were significantly decreased in diabetic rats when compared with control rats. Treatment with ST or vitamin E alone partly enhanced the amplitude of the contractions induced by EFS, but a combination of ST and vitamin E treatment showed no additional effects. Contractile response of the vas deferens to exogenous noradrenaline, was increased in diabetic rats when compared with control rats. While the addition of vitamin E alone had no effect, ST completely returned noradrenaline‐induced contractions to basal levels. The tension induced by 120 mm KCl was not statistically different among the experimental groups. In normal rats, EFS‐induced contractions were significantly inhibited by pyrogallol (10−4 m), a free‐radical generator. Percentage inhibition of pyrogallol on EFS (32 Hz)‐induced contractions in ring sections was 48 ± 5.8 in control, 75 ± 5.5 in untreated‐diabetic, 54 ± 2.7 in ST‐treated diabetic, and 58 ± 4.7 in vitamin E‐treated diabetic rats. Combining both ST and vitamin E treatment had the same effects as each antioxidant alone with a percent inhibition of 48 ± 6.8. These results are consistent with the degenerative changes seen in sympathetic nerves and the abnormal function observed in chronically diabetic rats, leading to a decrease in EFS response and an increase in response to adrenergic agonists in the vas deferens. Furthermore, we demonstrated that reactive oxygen species are responsible for impaired sympathetic neurotransmission and abnormal function of diabetic vas deferens, and that a combination of antioxidants may be better for the therapy of reproductive system disabilities in male diabetics.