bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of brassinosteroids in the sub‐femtomolar range using dansyl‐3‐aminophenylboronate derivatization and electrospray mass spectrometry
Authors: Svatoš Aleš , Antonchick Andrey , Schneider Bernd 
Published: March 2004

AbstractA selective and sensitive electrospray ionization (ESI) mass spectrometry based method for detection of brassinosteroids (BS) in plant samples was developed. The limit of detection (LOD) was dramatically reduced over existing analytical methods using a microbore (1.00 mm) C18 column and chemical derivatization of free BS to dansyl‐3‐aminophenylboronates. The LOD in the selected‐ion monitoring (SIM) mode for derivatized BS was 125 attomole (signal‐to‐noise ratio 3). The practical utility of the method is documented in Arabidopsis thaliana plant transformation of castasterone to brassinolide using a deuterium‐labeled precursor. The method could be very useful for the detection of native BS in plant tissue and biosynthetic studies. Copyright © 2004 John Wiley & Sons, Ltd.
Iterative computation of marginally stable trajectories
Authors: Hiskens I. A. 
Published: March 2004

AbstractStability limits place restrictions on the economic operation of power systems. Calculation of these limits is therefore very important, but has traditionally been quite difficult. This paper proposes an iterative algorithm for determining parameter values that result in marginal stability of a system. (A system is marginally stable for a particular disturbance if the post‐disturbance trajectory lies on the stability boundary.) The algorithm is based on Gauss–Newton solution of a nonlinear least‐squares problem. Gradient information is provided by trajectory sensitivities. Copyright © 2004 John Wiley & Sons, Ltd.
Analytical Identification of Limb Structures for Translational Parallel Manipulators
Authors: Fang Yuefa , Tsai Lung‐Wen 
Published: March 2004

AbstractA systematic analytical method, based on the theory of screws, is presented for identification of limb structures of general and over‐constrained 3‐degree‐of‐freedom (DOF) translational parallel manipulators. Given a system of wrenches of constraint, the corresponding reciprocal basis screws are determined. Then, the joint screws of a limb are obtained by a linear combination of these basis screws. Feasible limbs that can be used for construction of translational platforms are enumerated according to the type of constraint and the number of joints making up the limbs. © 2004 Wiley Periodicals, Inc.
Mixing in time and space for lattice spin systems: A combinatorial view
Authors: Dyer Martin , Sinclair Alistair , Vigoda Eric , Weitz Dror 
Published: March 2004

AbstractThe paper considers spin systems on thed‐dimensional integer lattice ℤdwith nearest‐neighbor interactions. A sharp equivalence is proved between decay with distance of spin correlations (aspatialproperty of the equilibrium state) and rapid mixing of the Glauber dynamics (atemporalproperty of a Markov chain Monte Carlo algorithm). Specifically, we show that if the mixing time of the Glauber dynamics isO(nlogn) then spin correlations decay exponentially fast with distance. We also prove the converse implication for monotone systems, and for general systems we prove that exponential decay of correlations impliesO(nlogn) mixing time of a dynamics that updates sufficiently large blocks (rather than single sites). While the above equivalence was already known to hold in various forms, we give proofs that are purely combinatorial and avoid the functional analysis machinery employed in previous proofs. © 2004 Wiley Periodicals, Inc. Random Struct. Alg., 2004
Methodical aspects in the surface analysis of supported molybdena catalysts
Authors: Briand Laura E. , Tkachenko Olga P. , Guraya Monica , Wachs Israel E. , Grünert Wolfgang 
Published: March 2004

AbstractSupported molybdena catalysts, with TiO2, CeO2 and Al2O3 supports, were studied by XPS and ISS. It was found that reliable results are obtained only when samples are calcined and transferred into the ultrahigh vacuum system without further contact with the ambient atmosphere (‘in situ calcination’). This applies also to catalysts that were previously calcined but had been stored in the ambient atmosphere. Supported Mo oxide becomes reduced under x‐ray irradiation during extended XPS data acquisition. A slight decrease of the Mo/support cation intensity ratio as a consequence of this reduction was detected by ISS in MoO3/TiO2 and MoO3/CeO2, therefore ISS analysis should be performed on freshly calcined samples without prior extended exposure to x‐rays. Because ISS spectra change rapidly due to sputtering, a correct analysis of the surface properties of the supported Mo catalyst requires extrapolation of the trend to the start of the experiment. It was established by this methodology that the surface of a 7% MoO3/TiO2 catalyst (5.3 Mo nm−2) is completely covered by a monolayer of Mo oxide species, and no Ti cation is exposed. In a submonolayer MoO3/CeO2 catalyst the exposed support could be detected, as expected, whereas in an MoO3/Al2O3 catalyst with an Mo oxide loading equal to the monolayer coverage a slight exposure of the Al support cation also was noted probably because of the high curvature of the smaller Al2O3 particles. Copyright © 2004 John Wiley & Sons, Ltd.
High‐energy monochromated Cu Kα1 x‐ray source for electron spectroscopy of materials: initial results
Authors: Beamson G. , Haines S. R. , Moslemzadeh N. , Tsakiropoulos P. , Weightman P. , Watts J. F. 
Published: March 2004

AbstractThe construction of an x‐ray source for high‐energy XPS studies, based on Cu Kα1 radiation (hν = 8047.8 eV), is described. This source has been fitted to a Scienta ESCA300 electron spectrometer and initial results for pure iron, chromium and stainless steel are presented. The Fe 1 s and Cr 1 s core levels (at ∼7112 and 5989 eV binding energy, respectively) are readily observed at good resolution along with their KLL Auger series. It is concluded that the new source shows much promise for investigation of the electronic structure of ferrous and other alloys of scientific and technological importance. Copyright © 2004 John Wiley & Sons, Ltd.
Upregulation of striatal adenosine A2A receptor mRNA in 6‐hydroxydopamine‐lesioned rats intermittently treated with L‐DOPA
Authors: Tomiyama Masahiko , Kimura Tamaki , Maeda Tetsuya , Tanaka Hiroyasu , Kannari Kazuya , Baba Masayuki 
Published: March 2004

AbstractTo determine whether the adenosine A2A receptor might play a role in L‐DOPA‐induced dyskinesia in Parkinson's disease, we analyzed changes in the expression of A2A receptor mRNA in response to intermittent treatment with L‐DOPA in rats with dopaminergic denervation by 6‐hydroxydopamine (OHDA) infusion into the medial forebrain bundle. Intermittent treatment with L‐DOPA increased A2A receptor mRNA levels in the dopamine‐depleted striatum of 6‐OHDA‐lesioned rats exhibiting behavioral sensitization to L‐DOPA. These results suggest that A2A receptor activation is associated with the development of motor complications induced by L‐DOPA treatment. Synapse 52:218–222, 2004. © 2004 Wiley‐Liss, Inc.
Electron microscopic dual labeling of high‐affinity neurotensin and dopamine D2 receptors in the rat nucleus accumbens shell
Authors: Delle Donne Karen T. , Chan June , Boudin Helene , Pélaprat Didier , Rostène William , Pickel Virginia M. 
Published: March 2004

AbstractThe dopamine D2 receptor (D2R) in the nucleus accumbens (NAc) shell is implicated in schizophrenia and in psychostimulant‐induced drug‐seeking behavior, both of which are affected by activation of the functionally opposed high‐affinity neurotensin receptor (NTS1). To determine the functionally relevant sites, we examined the dual electron microscopic immunocytochemical localization of D2R and NTS1 in the NAc shell of rat brain. Immunolabeling for each receptor was seen in association with cytoplasmic organelles, or more rarely, on the plasma membrane of both axonal and somatodendritic profiles. Some of the axonal and many of the dendritic processes colocalized the two receptors. The dually labeled axon terminals often formed symmetric synapses or appositional contacts with unlabeled dendritic profiles. The morphology of these terminals suggests that they contain either inhibitory amino acids or dopamine. Other axonal profiles expressing exclusively NTS1 or D2R were without synaptic specializations or formed asymmetric, excitatory‐type synapses mainly on unlabeled dendritic spines. In addition, however, several D2R‐immunoreactive terminals were observed presynaptic to dendrites containing NTS1. The somatodendritic profiles immunolabeled for NTS1 and/or D2R had morphological features typical of inhibitory spiny projection neurons in the NAc. These results suggest that activation of NTS1 and D2R can dually modulate transmitter release from the same or separate phenotypically distinct axon terminals in the NAc shell. These presynaptic receptors as well as the postsynaptic NTS1 distribution in neurons that also contain or receive input from terminals containing D2R may mediate the opposing actions of neurotensin and dopamine in the NAc. Synapse 52:176–187, 2004. © 2004 Wiley‐Liss, Inc.
Does ultrasound examination when the cervix is unfavorable improve the prediction of failed labor induction?
Authors: Roman H. , Verspyck E. , Vercoustre L. , Degre S. , Col J. Y. , Firmin J. M. , Caron P. , Marpeau L. 
Published: March 2004

AbstractObjectiveTo compare the Bishop score, ultrasound cervical parameters and fetal fibronectin assessment for predicting failed labor induction when the cervix is unfavorable.MethodA prospective observational study was performed in 106 consecutive pregnant women with a Bishop score ≤5 undergoing labor induction. Assessment of fetal fibronectin and ultrasound measurement of cervical length, cervical wedging and cervical lip areas were performed. The relationship between these parameters and failure of labor induction was determined.ResultsFailure of labor induction was defined as failure to reach a cervical dilatation of ≥5 cm, and it occurred in 16 patients (15.1%). Induction failure was associated with low Bishop scores before (P = 0.004) and 6 h after the start of induction (P = 0.007), increased clinical cervical length (P = 0.02) and increased ultrasound anterior cervical lip area (P = 0.04). The logistic regression model identified the Bishop score before induction (odds ratio = 2.25; 95% CI, 1.30–3.91; P = 0.003) and the clinical cervical length (odds ratio = 3.95; 95% CI, 1.3–11.7; P = 0.01) as being independent predictors of failed induction. To predict an induction failure, the best Bishop score cut‐off value was 4, with a sensitivity of 87.5%, a specificity of 45.6%, a likelihood ratio of 1.58, a positive predictive value of 22.2% and a negative predictive value of 95.4%.ConclusionCompared with the Bishop score, cervical length by ultrasound is not a better predictor for the outcome of labor induction in an unfavorable cervix. Nevertheless, the Bishop score appears to be of poor predictive value for failed induction of labor. Copyright © 2004 ISUOG. Published by John Wiley & Sons, Ltd.
Mickey Mouse and Milton: book publishing in the humanities
Authors: Cronin Blaise , La Barre Kathryn 
Published: March 2004

ABSTRACTWe report the results of a survey of tenure and promotion criteria in university departments of literature and language in the US. It is clear that the publication of a scholarly monograph remains a conditio sine qua non for the awarding of tenure. We analyze the language of institutional guidelines and standards: these range from the highly concrete to the intentionally vague.
The role of China's English‐language scientific journals in scientific communication
Authors: Ren Shengli , Rousseau Ronald 
Published: March 2004

ABSTRACTBetween 1929 and 2002 over 200 English‐language scientific journals were founded in China. The number of China's English edition journals in each discipline is, however, not correlated to the corresponding output of China's articles listed in the ISI's Science Citation Index. Clearly, the goal of these journals is to be internationally recognized. It is shown that this goal is rarely achieved. We think that lack of good‐quality papers, low international visibility and a citation ‘Matthew effect’ are the main causes for the small role played by China's English‐language journals.
The response of internal dynamics to hydrophobic core mutations in the SH3 domain from the Fyn tyrosine kinase
Authors: Mittermaier Anthony , Kay Lewis E. 
Published: March 2004

AbstractWe have used 15N‐ and 2H‐NMR spin relaxation experiments to study the response of backbone and side‐chain dynamics when a leucine or valine is substituted for a completely buried phenylalanine residue in the SH3 domain from the Fyn tyrosine kinase. Several residues show differences in the time scales and temperature dependences of internal motions when data for the three proteins are compared. Changes were also observed in the magnitude of dynamics, with the valine, and to a lesser extent leucine mutant, showing enhanced flexibility compared to the wild‐type (WT) protein. The motions of many of the same amide and methyl groups are affected by both mutations, identifying a set of loci where dynamics are sensitive to interactions involving the targeted side chain. These results show that contacts within the hydrophobic core affect many aspects of internal mobility throughout the Fyn SH3 domain.
Similar active sites in lysostaphins and D‐Ala‐D‐Ala metallopeptidases
Authors: Bochtler Matthias , Odintsov Sergey G. , Marcyjaniak Malgorzata , Sabala Izabela 
Published: March 2004

AbstractSpecific peptidases exist for nearly every amide linkage in peptidoglycan. In several cases, families of peptidoglycan hydrolases with different specificities turned out to be related. Here we show that lysostaphin‐type peptidases and D‐Ala‐D‐Ala metallopeptidases have similar active sites and share a core folding motif in otherwise highly divergent folds. The central Zn2+ is tetrahedrally coordinated by two histidines, an aspartate, and a water molecule. The Zn2+ chelating residues occur in the order histidine, aspartate, histidine in all sequences and contact the metal via the Nε, the Oδ, and the Nδ, respectively. The identity of the other active‐site residues varies, but in all enzymes of known structure except for VanX, a conserved histidine is present two residues upstream of the second histidine ligand to the Zn2+. As the same arrangement of active‐site residues is also found in the N‐terminal, cryptic peptidase domain of sonic hedgehog, we propose that this arrangement of active‐site residues be called the “LAS” arrangement, because it is present in lysostaphin‐type enzymes, D‐Ala‐D‐Ala metallopeptidases, and in the cryptic peptidase in the N‐domain of sonic hedgehog.
NMR structure of the noncytotoxic α‐sarcin mutant Δ(7‐22): The importance of the native conformation of peripheral loops for activity
Authors: García‐Mayoral Ma Flor , García‐Ortega Lucia , Lillo Ma Pilar , Santoro Jorge , Martínez Del Pozo Álvaro , Gavilanes José G. , Rico Manuel , Bruix Marta 
Published: March 2004

AbstractThe deletion mutant Δ(7‐22) of α‐sarcin, unlike its wild‐type protein counterpart, lacks the specific ability to degrade rRNA in intact ribosomes and exhibits an increased unspecific ribonuclease activity and decreased interaction with lipid vesicles. In trying to shed light on these differences, we report here on the three‐dimensional structure of the Δ(7‐22) α‐sarcin mutant using NMR methods. We also evaluated its dynamic properties on the basis of theoretical models and measured its correlation time (6.2 nsec) by time‐resolved fluorescence anisotropy. The global fold characteristic of ribotoxins is preserved in the mutant. The most significant differences with respect to the α‐sarcin structure are concentrated in (1) loop 2, (2) loop 3, which adopts a new orientation, and (3) loop 5, which shows multiple conformations and an altered dynamics. The interactions between loop 5 and the N‐terminal hairpin are lost in the mutant, producing increased solvent accessibility of the active‐site residues. The degree of solvent exposure of the catalytic His 137 is similar to that shown by His 92 in RNase T1. Additionally, the calculated order parameters of residues belonging to loop 5 in the mutant correspond to an internal dynamic behavior more similar to RNase T1 than α‐sarcin. On the other hand, changes in the relative orientation of loop 3 move the lysine‐rich region 111–114, crucial for substrate recognition, away from the active site. All of the structural and dynamic data presented here reveal that the mutant is a hybrid of ribotoxins and noncytotoxic ribonucleases, consistent with its biological properties.
Comparison of sun protection factors determined by an in vivo and different in vitro methodologies: a study with 58 different commercially available sunscreen products
Authors: Heinrich U. , Tronnier H. , Kockott D. , Kuckuk R. , Heise H. M. 
Published: March 2004

SynopsisAn extensive study on the sun protection factors (SPF) of sun care products was carried out using the COLIPA (The European Cosmetic Toiletry and Perfumery Association) method, which relates to in vivo experiments. Furthermore, in vitro methods were tested with sunscreen formulations that were prepared as films on surface‐roughened plates of polymethyl methacrylate (PMMA). One of the in vitro methods, i.e. using the sunscreen tester, has been recently developed, whereas the second has been defined by a pure spectroscopic approach, which is based on spectral transmission measurements of sunscreen films. Altogether 58 different sunscreen formulations, with manufacturer declared SPF values ranging from 4 to 60 and currently available on the European market, were investigated. The quality of correlations with results from the individual products based on the different in vitro methods versus the COLIPA values that were considered as generally accepted standard values was assessed. In this context, also variations because of sample preparation and spectral measurement were discussed. For sunscreen products with in vivo SPF values larger 25, the spectral transmittance within the UVA/UVB range is rapidly decreasing, which is experienced even for products with reduced amounts reaching 0.5 mg cm−2 and still leading to unsatisfactory correlation of the spectroscopically derived SPF values versus the results from the alternative assays. Opposite to these small amounts, a sunscreen product spread of 2 mg cm−2 is standard for the in vivo COLIPA method, whereas an area‐normalized amount of 1 mg cm−2 is currently routinely used for the sunscreen tester method. Furthermore, an overview of the individual product characteristics, such as their specific critical wavelengths and their UVA/UVB ratios is provided; both parameters can also be calculated from the spectral absorbances of the standardized sunscreen films.
Serious adverse events in the Australian National Evaluation of Pharmacotherapies for Opioid Dependence (NEPOD)
Authors: Digiusto E. , Shakeshaft A. , Ritter A. , O'Brien S. , Mattick R. P. ,   the NEPOD Research Group
Published: March 2004

ABSTRACTAims  The study estimated serious adverse event (SAE) rates among entrants to pharmacotherapies for opioid dependence, during treatment and after leaving treatment.Design  A longitudinal study based on data from 12 trials included in the Australian National Evaluation of Pharmacotherapies for Opioid Dependence (NEPOD).Participants and settings  A total of 1244 heroin users and methadone patients treated in hospital, community and GP settings.Intervention  Six trials included detoxification; all included treatment with methadone, buprenorphine, levo‐alpha‐acetyl‐methadol (LAAM) or naltrexone.Findings  During 394 person‐years of observation, 79 SAEs of 28 types were recorded. Naltrexone participants experienced 39 overdoses per 100 person‐years after leaving treatment (44% occurred within 2 weeks after stopping naltrexone). This was eight times the rate recorded among participants who left agonist treatment. Rates of all other SAEs were similar during treatment versus out of treatment, for both naltrexone‐treated and agonist‐treated participants. Five deaths occurred, all among participants who had left treatment, at a rate of six per 100 person‐years. Total SAE rates during naltrexone and agonist treatments were similar (20, 14 per 100 person‐years, respectively). Total SAE and death rates observed among participants who had left treatment were three and 19 times the corresponding rates during treatment.Conclusions  Individuals who leave pharmacotherapies for opioid dependence experience higher overdose and death rates compared with those in treatment. This may be due partly to a participant self‐selection effect rather than entirely to pharmacotherapy being protective. Clinicians should alert naltrexone treatment patients in particular about heroin overdose risks. Duty of care may extend beyond cessation of dosing.
The Japanese Society of Alcohol‐Related Problems
Authors: Maruyama Katsuya , Higuchi Susumu 
Published: March 2004

ABSTRACTThis paper presents an outline of the Japanese Society of Alcohol‐Related Problems. The precursor of the Society was the Japan Alcoholism Treatment Research Group, inaugurated in 1979, by merging two local research groups in the Tokyo and Osaka areas, both of which were exclusive gatherings of psychiatrists associated with alcoholism clinics. The Research Group developed into the Society in 1992, as the number of participants including those from other medical professions increased yearly, and the subjects of the group widened to include all addictive behaviours. In reflecting the process of establishment, it is unique in many aspects as a scientific society. The Society is not a science‐orientated body for presentation of new research findings. The main programme of the annual meeting is therefore a set of symposia in which members participate and discuss clinical and/or social problems arising from dependency on alcohol or drugs. Perhaps because of its content, the annual meeting is attended each year by the largest number of participants among all the societies in Japan concerned with alcohol and drugs. For the next several years, the Society's activities will be directed at (1) establishment of guidelines for early identification of and intervention in alcohol‐related problems; (2) expansion of its membership to include those in related fields of medicine and non‐medical professions; (3) improvement of the system of journal publication; and (4) creation of a system for timely adequate response to social problems associated with drugs and alcohol.