bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparing data mining methods on the VAERS database
Authors: Banks David , Woo Emily Jane , Burwen Dale R. , Perucci Phil , Braun M. Miles , Ball Robert
Published: June 2005

Purpose

Data mining may enhance traditional surveillance of vaccine adverse events by identifying events that are reported more commonly after administering one vaccine than other vaccines. Data mining methods find signals as the proportion of times a condition or group of conditions is reported soon after the administration of a vaccine; thus it is a relative proportion compared across vaccines, and not an absolute rate for the condition. The Vaccine Adverse Event Reporting System (VAERS) contains approximately 150 000 reports of adverse events that are possibly associated with vaccine administration.

Methods

We studied four data mining techniques: empirical Bayes geometric mean (EBGM), lower‐bound of the EBGM's 90% confidence interval (EB05), proportional reporting ratio (PRR), and screened PRR (SPRR). We applied these to the VAERS database and compared the agreement among methods and other performance properties, particularly focusing on the vaccine–event combinations with the highest numerical scores in the various methods.

Results

The vaccine–event combinations with the highest numerical scores varied substantially among the methods. Not all combinations representing known associations appeared in the top 100 vaccine–event pairs for all methods.

Conclusions

The four methods differ in their ranking of vaccine–COSTART pairs. A given method may be superior in certain situations but inferior in others. This paper examines the statistical relationships among the four estimators. Determining which method is best for public health will require additional analysis that focuses on the true alarm and false alarm rates using known vaccine–event associations. Evaluating the properties of these data mining methods will help determine the value of such methods in vaccine safety surveillance. Copyright © 2005 John Wiley & Sons, Ltd.
Products from solvolysis reactions that form (2‐phenylcyclopropyl)carbinyl cations
Authors: Chandrasena R. Esala P. , Aebisher David , Newcomb Martin
Published: June 2005

Products from solvolytic reactions that form the (2‐phenylcyclopropyl)carbinyl cation were determined. The majority of products (> 98%) derived from the 1‐phenyl‐3‐butenyl cation, consistent with reports by Wiberg and co‐workers. Small amounts of products derived from the 1‐phenyl‐1‐cyclopropylmethyl cation also were found; these products were previously predicted to be formed from reactions of the title cation. Although the 1‐phenyl‐1‐cyclopropylmethyl cation is considerably more stable than the 1‐phenyl‐3‐butenyl cation, it is not kinetically accessible under a variety of solvolytic conditions. Copyright © 2005 John Wiley & Sons, Ltd.
Kinetics and mechanism of the reaction of substituted benzyl chlorides with copper in dimethylformamide
Authors: Egorov Anatoly M. , Matyukhova Svetlana A. , Anisimov Alexander V.
Published: June 2005

The reaction of copper metal with various substituted benzyl chlorides in dimethylformamide was studied. The kinetic and thermodynamic parameters of the reaction was clarified. Hammett plots of log(k/k0) vs the substituent constant σ gave a good correlation (ρ = 0.43, Sρ = 0.05, r = 0.960). The structure of the organic group has little effect on the rate of reaction of substituted benzyl chlorides with copper. In the absence of atmospheric oxygen, the oxidative dissolution of copper proceeded via a single‐electron transfer mechanism with formation of 1,2‐diphenylethanes and copper(I) complexes. The stereochemistry and intermediate compound were also studied. The reaction mechanism is discussed. Copyright © 2005 John Wiley & Sons, Ltd.
Supramolecular assemblies of crown‐containing 4‐styrylpyridine in the presence of metal cations
Authors: Fedorov Y. V. , Fedorova O. A. , Andryukhina E. N. , Shepel N. E. , Mashura M. M. , Gromov S. P. , Kuzmina L. G. , Churakov A. V. , Howard J. A. K. , Marmois E. , Oberlé J. , Jonusauskas G. , Alfimov M. V.
Published: June 2005

Optical and x‐ray experiments showed the possibility of studying 4‐styrylpyridine with a 15‐crown‐5 ether fragment to bind metal cations through the participation of two centres: the crown ether moiety and the heterocyclic part. The metal cations studied can be divided into three groups. Alkaline earth metal cations form complexes with the crown ether centre, H+, Co2+ and Cd2+ prefer coordination with the N‐atom of heterocyclic part and Hg2+ cations form complexes through coordination with both binding centres. Copyright © 2005 John Wiley & Sons, Ltd.
A psbA mutation in Kochia scoparia (L) Schrad from railroad rights‐of‐way with resistance to diuron, tebuthiuron and metribuzin
Authors: Mengistu Lemma W , Christoffers Michael J , Lym Rodney G
Published: June 2005

Kochia [Kochia scoparia (L) Schrad] has become resistant to many herbicides used in cropland and railroad rights‐of‐way in North Dakota and Minnesota. Kochia scoparia plants that had survived annual treatments with diuron and tebuthiuron were sampled along railroad rights‐of‐way in North Dakota and Minnesota. The samples were screened in the greenhouse for resistance to diuron, tebuthiuron, metribuzin and bromoxynil from 0.5× to 32× the recommended use rates. A resistant K scoparia accession (MN‐3R) was confirmed with resistance up to 16‐fold higher than recommended use rates for tebuthiuron and diuron and up to 4‐fold higher for metribuzin. However, the resistant K scoparia accession was susceptible to bromoxynil even at 50% of the recommended use rate. The herbicide binding region of the psbA gene fragment of eight resistant (R) and seven susceptible (S) K scoparia accessions was PCR‐amplified and sequenced for detection of mutations. The psbA gene of four R K scoparia accessions was mutated at residue 219 with substitution of isoleucine for valine (GenBank accession number AY251265). The seven S K scoparia accession sequences were wild‐type at this residue (GenBank accession number AY251266). The other four R accessions sequences showed a previously known triazine R mutation with substitution of glycine for serine at residue 264. All 15 K scoparia accessions were wild‐type at all other psbA residues within the region analyzed. Resistance to diuron, tebuthiuron and metribuzin among the railroad rights‐of‐way K scoparia is probably due to the mutation at residue 219 of the psbA gene in some plants, but due to the previously reported Ser264Gly substitution in other plants. Target‐site resistance associated with a change of valine to isoleucine at residue 219 of the psbA target‐site in weeds has previously been reported for Poa annua L selected in diuron‐treated grass seed fields, and for Amaranthus powelli S Wats selected in linuron‐treated carrot fields. This is the first report of the mutation in herbicide‐resistant K scoparia. Copyright © 2005 Society of Chemical Industry
Evaluation of phenylaminopyrimidines as antifungal protein kinase inhibitors
Authors: Pillonel Christian
Published: June 2005

The effects of diverse phenylaminopyrimidines (PAP), namely PAP‐pyridines (type A), PAP‐pyrazoles (type B) and PAP‐thiazoles (type C), on Neurospora crassa Shear & Dodge has been investigated. The results revealed that type A strongly inhibit the in vitro growth of N crassa, whereas types B and C are much less active. A significant correlation was observed between the Neurospora growth inhibition and the intrinsic activity of type A compounds on the cyclin‐dependent protein kinase p34CDC2 of starfish, suggesting that the target of phenylaminopyrimidines in fungi is a cyclin‐dependent protein kinase (CDK). The phenylaminopyrimidine‐binding CDKs Phoss (major band) and CDC2 (minor band) involved in phosphorus uptake, glycogen synthesis and the cell cycle were identified from N crassa by affinity chromatography on phenylaminopyrimidine–sepharose. Comparative experiments with different protein kinases revealed the importance of the side chain of phenylaminopyrimidines for their target selectivity. A type B compound was found to selectively inhibit the MAP‐kinase OS‐2 involved in the osmoregulatory pathway of Neurospora. Copyright © 2005 Society of Chemical Industry
Convergent solid‐phase synthesis of hirudin
Authors: Goulas Spyros , Gatos Dimitrios , Barlos Kleomenis
Published: June 2005

Hirudin variant 1 (HV1), a small protein consisting of 65 amino acids and three disulfide bonds, was synthesized by using Fmoc‐based convergent methods on 2‐chlorotrityl resin (CLTR). The linear sequence was assembled by the sequential condensation of 7 protected fragments, on the resin‐bound 55–65 fragment. The conditions of fragment assembly were carefully studied to determine the most efficient synthetic protocol. Crude reduced [Cys16, 28(Acm)]‐HV1 thus obtained was easily purified to homogeneity by RP‐HPLC. Disulfide bridges were successfully formed by a two‐step procedure, involving an oxidative folding step to form Cys6–Cys14 and Cys22–Cys39 linkages, followed by iodine oxidation to form the Cys16–Cys28 bond. The correct disulfide bond alignment was established by peptide mapping using Staphylococcus aureus V8 protease at pH 4.5. Copyright © 2005 European Peptide Society and John Wiley & Sons, Ltd.
Tunneling time for phonons: dependence on the system's size
Authors: Villegas Diosdado , de León‐Pérez Fernando , Pérez‐Alvarez Rolando
Published: June 2005

We discuss the physical conditions under which the tunneling time for long‐wavelength phonons through semiconductor heterostructures is independent of the system's size, i.e. the effect equivalent to the Hartman effect for electrons. An analysis of the vibrational energy stored in the system is shown to be relevant for this study. In fact, the phonon Hartman effect is explained on the basis of saturation of the stored vibrational energy. Both acoustic and optical phonons are considered. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electronic properties of double perovskite compounds
Authors: Carvajal E. , Navarro O. , Allub R. , Avignon M. , Alascio B.
Published: June 2005

The double perovskites family A2MM′O6 (A being an alkaline‐earth and M, M′ two different transition‐metal elements) is considered as a serious candidate for magnetoelectronic applications. It appears to be fundamental to understand the role of electronic parameters controlling the half‐metallic ground state and high Curie temperature Tc. In this respect it is very interesting that different members of the family present a variety of electronic and magnetic properties. Among them, Sr2FeMoO6 and Sr2FeReO6 are half‐metallic ferromagnets with fairly large Tc(≈450 K) while Sr2FeWO6 is known as an antiferromagnetic insulator with TN ≈ 37 K. As expected, a metal–insulator and magnetic transition has been reported in the substituted compounds Sr2FeMoxW1–xO6. To elucidate the origin of such different behavior in these Sr2FeMO6 double perovskites we consider a correlated electron picture with localized Fe‐spins (d5 configuration) and conduction electrons originating from M (M = Mo, Re or W) together with the double‐exchange type interaction taking place in the hybridized Fe–M t2g band and competing with the antiferromagnetic superexchange interactions between the Fe‐spins. We consider here only the ordered stucture in which Fe and M constitute two interpenetrating sublattices. Using a tight‐binding model and the renormalized perturbation expansion technique, we calculate the density of states and determine the behaviour of the critical temperature as a function of the band filling and the Fe–M charge transfer energy. This allows us to discuss the stability of the half‐metallic ferromagnetic state with increasing charge transfer energy. We will also discuss the electronic properties and the ferro‐antiferromagnetic transition in the substituted compounds like Sr2FeMoxW1–xO6, when disorder among Mo/W takes place in the M‐sublattice. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optical, electrical and structural characterization of CuInSe2 thin films
Authors: Calderón C. , Gordillo G. , Romero E. , Bolaños W. , Bartolo‐Pérez P.
Published: June 2005

Structural, optical and electrical properties of polycrystalline p‐type CuInSe2 (CIS) thin films, grown by a process including a chemical reaction between Cu and InxSey thin films deposited sequentially by evaporation, followed by annealing in a Se environment, were studied through XRD (X‐ray diffraction), transmittance and Hall voltage measurements. The conditions to grow CIS thin films in the α phase of the chalcopyrite structure were found through a parameter study. CIS films with these characteristics are usually used for the fabrication of high efficiency solar cells. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Study of electrical transport properties of ZnO thin films used as front contact of solar cells
Authors: Calderón C. , Gordillo G. , Olarte J.
Published: June 2005

This work is focused on the study of possible mechanisms affecting the electrical transport properties of ZnO thin films. The films were deposited using the reactive evaporation technique, obtaining transmittances greater than 80% and resistivities of the order of 8 × 10–4 Ω cm without using extrinsic doping. This films are suitable for transparent front contact of solar cells.

Measurements of resistivity and Hall coefficient, as a function of temperature, were performed on the films. The interpretation of these results was done with the help of a theoretical calculation of the carrier mobility as a function of the temperature. Several scattering mechanisms affecting the electrical transport in the temperature range studied (90 K–680 K) were found. The most important are processes occurring in the grain boundaries and interactions of free carriers with ionized impurities. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Phase‐glass scaling near the coherence transition in granular HoBa2Cu3O7–δ superconducting thin films
Authors: Roa‐Rojas J. , Landínez Téllez D. A. , Prieto P.
Published: June 2005

Systematic measurements of electrical magnetoconductivity near the coherence transition of granular HoBa2Cu3O7–δ thin films are reported. Experiments performed in magnetic fields ranging from 0 to 2500 Oe reveal that close to the coherence transition temperature Tc0(H), the correlation length scales as a power law of temperature with a thermal‐dependent critical exponent, ν. In low external fields the corresponding value of ν is consistent with the two‐dimensional phase‐glass model, which is in the same dynamical universality class of the so‐called vortex‐glass model. At applied fields H > 1000 Oe, the vortex dynamics becomes stronger and the coherence transition is not observed. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Li2O at high pressures: structural properties, phase‐transition, and phonons
Authors: Kunc K. , Loa I. , Grzechnik A. , Syassen K.
Published: June 2005

A structural phase transition in Li2O, from the anti‐fluorite to the anti‐cotunnite structure, is evidenced by angle‐dispersive synchrotron X‐ray powder diffraction and supported by ab initio calculations. The equations of state E(V), P(V) and the enthalpies H(P) are determined, for both phases, using total‐energy calculations based on the Projector Augmented Waves method. The calculations supply the value of the transition pressure at T = 0 and in the ‘ideal conditions’ and provide detailed information on all 9 structural parameters describing the anti‐cotunnite structure of Li2O at various pressures. We also report Raman frequencies, calculated for both phases and measured in the anti‐fluorite phase, so as to provide a tool for monitoring the approach and the progress of the transformation. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the detailed mechanism of the burn‐in in GaInP/GaAs HBTs
Authors: Cabrera‐Arenas V. , Mimila‐Arroyo J.
Published: June 2005

The evolution of the base current of GaInP/GaAs Heterojunction Bipolar Transistors (HBTs) is studied as a function of the stressing current during the burn‐in. It is found that the base current decreases in an exponential way with the involved time constants depending themselves on the stressing current in a way proportional to I–2. Such behaviour is explained considering two independent recombination centres that are deactivated during the stressing by the capture of two electrons. These two recombination centres might be H+ and the quasi complex Si+–H+ which capture two electrons each becoming H− and SiH. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Thermally Driven Interfacial Dynamics of Metal/Oxide Bilayer Nanoribbons
Authors: Law Matt , Zhang Xiao Feng , Yu Rong , Kuykendall Tevye , Yang Peidong
Published: June 2005

Solid–solid interfacial processes greatly affect the performance of electronic and composite materials, but probing the dynamics of buried interfaces is challenging and often involves lengthy or invasive sample preparation. We show that bilayer nanoribbons—made here of tin dioxide and copper—are convenient structures for observing as‐made interfaces as they respond to changing temperature in a transmission electron microscope (TEM). At low temperatures (<200 °C), differential thermal expansion causes the bilayers to bend when heated or cooled, with the motion determined by the extent of Cu–SnO2 epitaxy. At higher temperatures, we are able to watch—in real time and with nanometer resolution—a progression of grain growth, interdiffusion, island formation, solid‐state chemical reactions, and melting. This novel TEM geometry is readily applicable to other nanoribbon/coating combinations and is well suited to observing interfacial phenomena driven thermally or by the application of mechanical, electrical, or magnetic forces.
Genetic Counseling Outcomes: Perceived Risk and Distress After Counseling for Hereditary Colorectal Cancer
Authors: Codori Ann‐Marie , Waldeck Tracy , Petersen Gloria M. , Miglioretti Diana , Trimbath Jill D. , Tillery Miriam A.
Published: June 2005

Genetic counseling may turn risk information into cancer prevention behavior by modifying health beliefs and cancer‐related distress. We assessed the effect of genetic counseling on these factors in 101 adult first‐degree‐relatives of colorectal cancer patients from families with known or suspected hereditary nonpolyposis colorectal cancer. Before counseling and once afterward, subjects completed self‐report measures of perceived lifetime risk and cancer‐distress. Most persons overestimated their cancer risk, and higher perceived risk was associated with believing that colorectal cancer cannot be prevented. Individual perceived risk changed after counseling, although mean perceived risk was unchanged. After adjusting for baseline risk, older persons and those with higher estimated objective cancer risk had larger postcounseling decreases. Distress after counseling was positively correlated with baseline distress and anxiety symptoms, and inversely correlated with tolerance for ambiguity. The findings suggest counseling interventions that should increase the likelihood of screening and offer hypotheses for future research.
Emotional Responses to APO E Genotype Disclosure for Alzheimer Disease
Authors: Romero Linda J. , Garry Philip J. , Schuyler Mark , Bennahum David A. , Qualls Clifford , Ballinger Lori , Kelly Velma , Schmitt Cheryl , Skipper Betty , Ortiz Irene E. , Rhyne Robert L.
Published: June 2005

The purpose of our study is to assess the emotional responses to disclosing APO E genotype to asymptomatic older adults at increased risk for Alzheimer disease (AD). This is a longitudinal cohort study of volunteer subjects who were aged 50 years or over, asymptomatic for (AD), had a family history of AD, passed a psychological assessment, and participated in pre‐ and post‐test genetic counseling and three follow‐up visits over 10 months. We analyzed responses by three emotional constructs: depressed, worried, and relieved. Three hundred and twenty‐eight subjects were screened, 76 received their APO E genotype. When emotional responses occurred it was immediate, between baseline and the 1 month follow‐up. Emotional reactions did not change significantly past 1 month. Our results suggest that for emotionally stable persons, disclosing results of their APO E genotype, high risk subjects did not report more depression or worry and low risk subjects felt relieved by knowing the results. Future studies should evaluate the risks of disclosure to family members involved in the diagnostic work‐up of a relative and include subjects from a broader range of emotional stability and socioeconomic background.
A Practical Account of Autonomy: Why Genetic Counseling is Especially Well Suited to the Facilitation of Informed Autonomous Decision Making
Authors: Hodgson Jan , Spriggs Merle
Published: June 2005

In genetic counseling, facilitation of autonomous decision‐making is seen as a primary aim and respect for autonomy is used to justify a nondirective counseling approach whereby clients are free to make their own choices after being given all necessary information. However in the genetic counseling literature, autonomy as a concept appears to be interpreted variably and often narrowly. We offer a practical account of autonomy that is coherent, consistent and philosophically defensible for the genetic counseling setting. At the same time we demonstrate how nondirective counseling may serve to frustrate rather than facilitate client autonomy. We suggest that promoting purposeful dialogue rather than counseling that is nondirective is more conducive to client autonomy.
NSGC Foundations—Then, Now, and Tomorrow
Authors: Ormond Kelly
Published: June 2005

This 2004 Presidential Address was presented at the annual education conference of the National Society of Genetic Counselors in Washington DC on October 9, 2004.
Measurement Analogies: Comparisons of Behavioral And Physical Measures
Authors: Luce R. Duncan
Published: June 2005

Two examples of behavioral measurement are explored—utility theory and a global psychophysical theory of intensity—that closely parallel the foundations of classical physical measurement in several ways. First, the qualitative attribute in question can be manipulated in two independent ways. Second, each method of manipulation is axiomatized and each leads to a measure of the attribute that, because they are order preserving, must be strictly monotonically related. Third, a law-like constraint, somewhat akin to the distribution property underlying, e.g., mass measurement, links the two types of manipulation. Fourth, given the numerical measures that result from each manipulation, the linking law between them can be recast as a functional equation that establishes the connection between the two measures of the same attribute. Fifth, a major difference from most physical measurement is that the resulting measures are themselves mathematical functions of underlying physical variables—of money and probability in the utility case and of physical intensity and numerical proportions in the psychophysical case. Axiomatizing these functions, although still problematic, appears to lead to interesting results and to limit the degrees of freedom in the representations.
The Good State: in praise of ‘classical’ internationalism
Authors: LAWLER PETER
Published: June 2005

The end of the Cold War has seen Western internationalism migrate from the margins to the centre of International Relations theory and practice. As a consequence the modest ambitions of what we might now call ‘classical internationalism’ have come under challenge from more thoroughly cosmopolitan varieties from both the right and left of the mainstream Western political spectrum whose commonalities, moreover, are arguably becoming as prominent as their differences. This article attempts to recover the classical internationalist project and, more specifically, the understanding of statehood that underpins it. Some observations on the distinctions and tensions between varieties of contemporary internationalist and cosmopolitan thinking about international politics are followed by a critique of a pervasive scholarly disinterest in the varieties of Western internationalist states. These two exercises form the backdrop to advocacy of the idea of ‘the Good State’ as a response to dominant forms of contemporary Western cosmopolitanism and their critics.
Generalising the international
Authors: EDKINS JENNY , ZEHFUSS MAJA
Published: June 2005

Ironically, since 11 September 2001, world politics seems to have taken a turn towards certainty. This article is an intervention that demonstrates how the illusion of the sovereign state in an insecure and anarchic international system is sustained and how it might be challenged. It does so through a Derridean analysis of Hedley Bull's The Anarchical Society. The article examines how International Relations (IR) thinking works; it teases out the implications of our reading of Bull's work and proposes that what we call generalising the international could lead to an alternative analysis of world politics, one that retains an openness to the future and to politics.
Nesprins: intracellular scaffolds that maintain cell architecture and coordinate cell function?
Authors: Warren Derek T. , Zhang Qiuping , Weissberg Peter L , Shanahan Catherine M.
Published: June 2005

Nesprins are a recently discovered family of ubiquitously expressed intracellular proteins. Through alternative transcriptional initiation, termination and splicing, two genes – nesprin-1 and nesprin-2 (also known as syne-1 and syne-2) – give rise to many protein isoforms that vary markedly in size. The largest of these isoforms comprise a C-terminal transmembrane domain (the KLS domain) linked by a spectrin-repeat rod domain to an N-terminal paired, actin-binding, calponin-homology domain. This structure suggests that they are well suited to orchestrate signalling between cell membranes and the cytoskeleton. Other isoforms have variable lengths of this rod domain linked to either end of the protein. Smaller isoforms with the KLS domain are localised at the inner nuclear membrane, where they bind lamin A/C and emerin. Larger nesprin isoforms link the outer nuclear membrane with intracellular organelles and the actin cytoskeleton and are thought to regulate nuclear anchorage and organelle migration. Thus, nesprins might have a variety of fundamental roles in cells, particularly muscle cells where they are highly expressed. We speculate that nesprin mutations might contribute to a broad range of human disease syndromes, including laminopathies.
Measurements of ozone concentrations on a commercial vessel in the marine boundary layer over the northern North Pacific Ocean
Authors: Watanabe Koichi , Nojiri Yukihiro , Kariya Shigeru
Published: June 2005

The O3 concentration in the marine boundary layer over the northern North Pacific Ocean was measured on a commercial vessel. No significant longitudinal gradient was seen over the area between 170°E and 135°W. A spring O3 maximum and summer minimum were observed. A diurnal cycle of O3 was found, with a high nighttime concentration and a low daytime concentration. Throughout the year an O3 decrease was clearly observed just after sunrise, which is known as sunrise ozone destruction (SOD). SOD may act as an important O3 sink in the marine boundary layer. Dramatic O3 destruction (2.5–3 ppb hour−1) just after sunrise was found in spring 2001. The cause of this phenomenon is discussed.
Dynamics of the Saturnian inner magnetosphere: First inferences from the Cassini magnetometers about small‐scale plasma transport in the magnetosphere
Authors: André N. , Dougherty M. K. , Russell C. T. , Leisner J. S. , Khurana K. K.
Published: June 2005

The Cassini magnetometers reveal a very dynamic plasmadisc within the inner Saturnian magnetosphere during the first three orbits of the Cassini orbital tour. This corotation‐dominated region is known to contain various neutral and plasma populations and Voyager spacecraft observations suggest important radial transport processes redistribute the locally created plasma out to the remote magnetospheric regions, by a mechanism yet to be identified. In this work we report on anomalous magnetic field signatures in the inner regions of the magnetosphere (inside of 8 Saturn radii) that may participate in the radial transport and that seem to be consistent with signatures of interchanging flux tubes. These unusual events are characterized by sharp boundaries and abrupt changes of the magnetic pressure, consisting of depressions or enhancements of the field magnitude. They present some similarities with previously identified signatures of interchanging flux tubes in the Io torus, allowing the interesting possibility of carrying out a comparative study of these two environments.
Decoupling marine export production from new production
Authors: Plattner Gian‐Kasper , Gruber Nicolas , Frenzel Hartmut , McWilliams James C.
Published: June 2005

We investigate the relationship between annually integrated new and export production for the central Californian marine upwelling system using an eddy‐resolving coupled physical‐ecosystem‐biogeochemical model. We find that when averaged over the annual cycle lateral transport leads to a substantial spatial decoupling of export from new production, with a length‐scale of decoupling on the order of 300 km. The decoupling is largely caused by mean horizontal fluxes induced by persistent meso‐ and submesoscale circulation structures and to a lesser degree by the mean lateral offshore transport induced by Ekman transport. This indicates that the concept of numerically equal new and export production has to be used with great care, particularly in dynamic oceanic environments.
New positron emission tomography tracer [11C]carvedilol reveals P‐glycoprotein modulation kinetics
Authors: Bart Joost , Dijkers Eli C F , Wegman Theodora D , de Vries Elisabeth G E , van der Graaf Winette T A , Groen Harry J M , Vaalburg Willem , Willemsen Antoon T M , Hendrikse N Harry
Published: June 2005

Imaging of P‐glycoprotein (P‐gp) function in the blood–brain barrier (BBB) may support development of strategies, which will improve drug delivery to the brain. [11C]verapamil has been developed as a positron emission tomography (PET) tracer, to image P‐gp function in vivo. Ideally, for the purpose of brain imaging, tracers should have a log P between 0.9 and 2.5. The β‐receptor antagonist carvedilol is a P‐gp substrate with a log P=2.0, and can be labeled with [11C]. The aim of this study was to determine whether the P‐gp substrate [11C]carvedilol can be used as a PET tracer for visualisation and quantification of the P‐gp function in the BBB.

Cellular [11C]carvedilol accumulation in GLC4, GLC4/P‐gp, and GLC4/Adr cells increased three‐fold in the GLC4/P‐gp cells after pretreatment with cyclosporin A (CsA) whereas no effect of MK571 could be determined in the GLC4/Adr cells.

Ex vivo [11C]carvedilol biodistribution studies showed that [11C]carvedilol uptake in the brain was increased by CsA. [11C]carvedilol uptake in other organs was not affected by CsA.

Autoradiography studies of rat brains showed that [11C]carvedilol was homogeneously distributed over the brain and that pretreatment with CsA increased [11C]carvedilol uptake.

In vivo PET experiments were performed with and without P‐gp modulation by CsA. P‐gp mediated transport was quantified by Logan analysis of the PET data, calculating the distribution volume (DV) of [11C]carvedilol in the brain. Logan analysis resulted in excellent fits, revealing that [11C]carvedilol is not trapped in the brain. Brain DV of [11C]carvedilol showed a dose‐dependent increase of maximal three‐fold after CsA pretreatment. Above 15 mg kg−1, no change in DV was found. Compared to [11C]verapamil less CsA was needed to reach maximal DV, suggesting that [11C]carvedilol kinetics is a more sensitive tool to in vivo measure P‐gp function.

British Journal of Pharmacology (2005) 145, 1045–1051. doi:10.1038/sj.bjp.0706283
Effect of oral administration of zanapezil (TAK‐147) for 21 days on acetylcholine and monoamines levels in the ventral hippocampus of freely moving rats
Authors: Hatip‐Al‐Khatib Izzettin , Iwasaki Katsunori , Yoshimitsu Yoshitaka , Arai Takashi , Egashira Nobuaki , Mishima Kenichi , Ikeda Tomoaki , Fujiwara Michihiro
Published: June 2005

Zanapezil (TAK‐147 (3‐[1benzylpiperdin‐4‐yl]‐1‐(2,3,4,5‐tetrahydro‐1 H‐1‐benzazepin‐8‐yl) propan‐1‐one fumarate)) is a selective acetylcholine (ACh) esterase inhibitor under investigation as a drug for Alzheimer's disease (AD) treatment.

In this study, the effects of TAK‐147 at 2 mg kg−1 p.o. for 21 days, compared to donepezil (E2020), on the levels of ACh, catecolamines and indoleamines were investigated in the ventral hippocampus (VH) of freely moving rats by microdialysis‐high‐performance liquid chromatography.

The results revealed that the VH contains 92.05±21.97 fmol 20 μl−1 ACh and the following monoamines levels (pg 30 μl−1), norepinephrine (NE) 1.92±0.39, epinephrine (Epi) 1.91±0.183, 3‐methoxy‐4‐hydroxyphenylglycol (MHPG) 11.53±3.22, normetanephrine 3.26±0.61, dopamine (DA) 0.77±0.23, 3,4‐dihydroxyphenylacetic acid (DOPAC) 3.37±1.01, homovanillic acid (4‐hydroxy‐3‐methoxyphenylacetic acid; HVA) 4.04±0.93, 3‐methoxytyramine 0.64±0.13, serotonin (5‐HT) 0.73±0.16 and 5‐hydroxyindoleacetic acid (5‐HIAA) 313.15±18.42.

On the 21st day and prior to the last dose, TAK‐147 increased ACh, Epi, DA and 5‐HT, whereas E2020 increased MHPG, Epi and DA. Following the last dose, TAK‐147 increased NE, whereas E2020 increased NE, ACh and 5‐HT in addition to their effects prior to the last dose. TAK‐147 decreased HVA : DA ratio, but only marginally decreased DOPAC : DA and 5‐HIAA : 5‐HT ratios. On the other hand, E2020 decreased ratios of HVA : DA, DOPAC : DA (prior to the last dose), and 5‐HIAA : 5‐HT (90–180 min after the last dose). Both drugs decreased MHPG : NE only at 180 min after the last dose. The results also showed that TAK‐147 increased Epi : NE ratio prior to and for 120 min following the last dose, whereas E2020 increased the ratio only before the last dose. The present results show that TAK‐147 at a subthreshold dose could differentially increase ACh and 5‐HT, compared to MHPG increased by E2020. The last dose of each drug could extend their effects to other monoamines.

The increase of the monoamines levels, in addition to that on the ACh, and decrease of their oxidation could be of value in the treatment of the AD, other dementic diseases and the cohort neurological disorders depending on the type of the monoamine underlying the disorder.

British Journal of Pharmacology (2005) 145, 1035–1044. doi:10.1038/sj.bjp.0706288
Dual regulation of myofilament Ca2+ sensitivity by levosimendan in normal and acidotic conditions in aequorin‐loaded canine ventricular myocardium
Authors: Takahashi Reiko , Endoh Masao
Published: June 2005

Experiments were carried out in canine ventricular trabeculae loaded with aequorin to investigate the effects of levosimendan {(R)‐([4‐(1,4,5,6‐tetrahydro‐4‐methyl‐6‐oxo‐3‐pyridazinyl)phenyl]‐hydrazono)‐propanedinitrile} on contractile force and Ca2+ transients in normal and acidotic conditions.

The concentration–response curve for the positive inotropic effect (PIE) of levosimendan was bell‐shaped, that is, it declined markedly at 10−4 M after achieving the maximum at 10−5 M in normal (pHo=7.4) and acidotic conditions (pHo=6.6).

The positive inotropic effect (PIE) of levosimendan up to 10−5 M was associated with an increase in Ca2+ transients and a shift of the relationship of Ca2+ transients and force to the left of that of elevation of [Ca2+]o.

Levosimendan at 10−4 M elicited a negative inotropic effect (NIE) in association with a further increase in Ca2+ transients, and during washout Ca2+ transients increased further, while the force was abolished before both signals recovered to the control.

In acidotic conditions, the relationship of Ca2+ transients and force during the application of levosimendan in normal conditions was essentially unaltered, whereas the PIE was suppressed due to attenuation of the increase in Ca2+ transients.

In summary, in intact canine ventricular myocardium, levosimendan elicits a dual inotropic effect: at lower concentrations, it induces a PIE by a combination of increases in Ca2+ transients and Ca2+ sensitivity, while at higher concentrations it elicits an NIE due to a decrease in Ca2+ sensitivity. Acidosis inhibits the PIE of levosimendan due to suppression of the increase in Ca2+ transients in response to the compound.

British Journal of Pharmacology (2005) 145, 1143–1152. doi:10.1038/sj.bjp.0706292
Intrinsic inhibitory innervation of the stomach
Authors: Huizinga Jan D , Dixit Devika , Zarate Natalia
Published: June 2005

British Journal of Pharmacology (2005) 146, 163–164. doi:10.1038/sj.bjp.0706294
Reply to Huizinga et al.
Authors: Currò Diego
Published: June 2005

British Journal of Pharmacology (2005) 146, 164. doi:10.1038/sj.bjp.0706296
Extended quantization condition for constructive and destructive interferences and trajectories dominating molecular vibrational eigenstates
Authors: Ushiyama Hiroshi , Takatsuka Kazuo
Published: June 2005

The role of destructive quantum interference in semiclassical quantization of molecular vibrational states is studied. This aspect is crucial for correct quantization, since failure in the appropriate treatment of destructive interference quite often results in many spurious peaks and broad background to hide the true peaks. We first study the time-Fourier transform of the autocorrelation function without performing summation over the trajectories. The resultant quantity, the prespectrum which is a function of individual classical trajectories, provides a clear view about how destructive interference among the trajectories should function. It turns out that the prespectrum is oscillatory but never a random noise. On the contrary, it bears a systematic and regular structure, which is sometimes characterized in terms of very sharp and high peaks in the energy space of the sampled classical trajectories. We have found an extended quantization condition that is responsible for generating these peaks in the prespectrum, which we call the prior quantization condition. Integration of the prespectrum over the trajectory space is supposed to give “zero” (practically a small value of the order of the Planck constant) at a noneigenvalue energy, which is actually a materialization of the destructive interference. Besides, certain finite peaks in the prespectrum survive after the integration to form the true spikes (eigenvalues) in the final spectrum, if they satisfy an additional resonance condition. For these resonance components, the prior quantization condition is reduced to the Einstein–Brillouin–Keller quantization condition. Based on these analyses, we propose a rather conventional filtering technique to efficiently handle tedious computation for destructive interference, and numerically verify that it works well even for multidimensional chaotic systems. This filtering technique is further utilized to extract a few trajectories that dominate an eigenstate of molecular vibration.
Polarizability response in polar solvents: Molecular-dynamics simulations of acetonitrile and chloroform
Authors: Elola M. Dolores , Ladanyi Branka M.
Published: June 2005

The relaxation of the many-body polarizability in liquid acetonitrile and chloroform at room temperature was studied by molecular-dynamics simulations. The collective polarizability induced by intermolecular interactions was included using first- and all-orders dipole-induced-dipole models and calculated considering both molecule-centered and distributed site polarizabilities. The anisotropic response was analyzed using a separation scheme that allows a decomposition of the total response in terms of orientational and collision-induced effects. We found the method effective in approximately separating the contributions of these relaxation mechanisms, although the orientational-collision-induced interference makes a non-negligible contribution to the total response. In both liquids the main contribution to the anisotropic response is due to orientational dynamics, but intermolecular collision-induced (or translational) effects are important, especially at short times. We found that higher-order interaction-induced effects were essentially negligible for both liquids. Larger differences were found between the center-center and site-site models, with the latter showing faster polarizability relaxation and better agreement with experiment. Isotropic and anisotropic spectra were computed from the corresponding time correlation functions. The lowest-frequency contributions are largely supressed in the isotropic spectra and their overall shape is similar to the purely collision-induced contribution to the anisotropic spectra, but with an amplitude which is smaller by a factor of ∼5 in acetonitrile and ∼3 in chloroform.
Molecular applications of the intermediate Hamiltonian Fock-space coupled-cluster method for calculation of excitation energies
Authors: Musiał Monika , Meissner Leszek , Kucharski Stanisław A. , Bartlett Rodney J.
Published: June 2005

The intermediate Hamiltonian Fock-space coupled-cluster (FS-CC) method with singles and doubles is applied to calculate vertical excitation energies (EEs) for some molecular systems. The calculations are performed for several small molecules, such as H2O, N2, and CO, and for larger systems, such as C2H4, C4H6, and C6H6. Due to the intermediate Hamiltonian formulation, which provides a robust computational scheme for solving the FS-CC equations, and the efficient factorization strategy, relatively large basis sets and model spaces are employed permitting a comparison of the calculated vertical EEs with the experimental data.
Extrapolated intermediate Hamiltonian coupled-cluster approach: Theory and pilot application to electron affinities of alkali atoms
Authors: Eliav Ephraim , Vilkas Marius J. , Ishikawa Yasuyuki , Kaldor Uzi
Published: June 2005

The intermediate Hamiltonian (IH) coupled-cluster method makes possible the use of very large model spaces in coupled-cluster calculations without running into intruder states. This is achieved at the cost of approximating some of the IH matrix elements, which are not taken at their rigorous effective Hamiltonian (EH) value. The extrapolated intermediate Hamiltonian (XIH) approach proposed here uses a parametrized IH and extrapolates it to the full EH, with model spaces larger by several orders of magnitude than those possible in EH coupled-cluster methods. The flexibility and resistance to intruders of the IH approach are thus combined with the accuracy of full EH. Various extrapolation schemes are described. A pilot application to the electron affinities (EAs) of alkali atoms is presented, where converged EH results are obtained by XIH for model spaces of ∼20000 determinants; direct EH calculations converge only for a one-dimensional model space. Including quantum electrodynamic effects, the average XIH error for the EAs is 0.6meV and the largest error is 1.6meV. A new reference estimate for the EA of Fr is proposed at 486±2meV.
Investigating the breakup dynamics of dihydrogen sulfide ions recombining with electrons
Authors: Hellberg Fredrik , Zhaunerchyk Vitali , Ehlerding Anneli , Geppert Wolf D. , Larsson Mats , Thomas Richard D. , Bannister Mark E. , Bahati Eric , Vane C. Randy , Österdahl Fabian , Hlavenka Petr , af Ugglas Magnus
Published: June 2005

This paper presents results concerning measurements of the dissociative recombination (DR) of dihydrogen sulfide ions. In combination with the ion storage ring CRYRING an imaging technique was used to investigate the breakup dynamics of the three-body channel in the DR of SD2+32. The two energetically available product channels S(P3)+2D(S2) and S(D1)+2D(S2) were both populated, with a branching fraction of the ground-state channel of 0.6(0.1). Information about the angle between the two deuterium atoms upon dissociation was obtained together with information about how the available kinetic energy was distributed between the two light fragments. The recombination cross sections as functions of energy in the interval of 1 meV to 0.3 eV in the center-of-mass frame are presented for SH2+34. The thermal rate coefficient for the DR of SH2+34 was determined to be (4.8±1.0)×10−7(T∕300)−0.72±0.1cm3s−1 over this interval.
Determining the vibrational pattern via overtone cold spectra: C–H methyl stretches of propyne
Authors: Portnov Alex , Bespechansky Evgeny , Ganot Yuval , Rosenwaks Salman , Bar Ilana
Published: June 2005

Vibrationally mediated photodissociation and photoacoustic (PA) spectroscopy were employed for studying the intramolecular dynamics of propyne initially excited to the first through fourth overtone of methyl C–H stretching modes. Room-temperature PA and jet-cooled action spectra, monitoring the absorption of the parent and the yield of the ensuing H photofragments, respectively, were obtained. The PA spectra exhibit mainly broad features, while the action spectra, due to inhomogeneous structure reduction, expose multiple peaks of recognizable shapes in the differing overtone manifolds. Symmetric rotor simulations of the band contours of the action spectra allowed retrieving of band origins and linewidths. The linewidths of the bands in each manifold enabled estimates for energy redistribution times out of the corresponding states to the bath states, the times ranging from 18±6ps for two quanta of C–H excitation to subpicosecond for five quanta. The data were also analyzed in terms of a normal-mode model and a joint local-/normal-mode model. These models enabled determination of harmonic frequencies, anharmonicities, and interaction parameters reproducing the observed data in all monitored regions and provided spectral assignments. The measured Doppler profiles were well fitted by Gaussians with widths suggesting low average translational energies for the released H photofragments. These low energies and their similarities to those for dissociation of propyne isotopomers preexcited to acetylenic C–H stretches were ascribed to an indirect dissociation process occurring after internal conversion to the ground electronic state and isomerization to allene.
Photoelectron spectroscopy of the [glycine∙(H2O)1,2]− clusters: Sequential hydration shifts and observation of isomers
Authors: Diken Eric G. , Headrick Jeffrey M. , Johnson Mark A.
Published: June 2005

The electron binding energies of the small hydrated amino acid anions, [glycine∙(H2O)1,2]−, are determined using photoelectron spectroscopy. The vertical electron detachment energies (VDEs) are found to increase by approximately 0.12 eV with each additional water molecule such that the higher electron binding isomer of the dihydrate is rather robust, with a VDE value of 0.33 eV. A weak binding isomer of the dihydrate is also recovered, however, with a VDE value (0.14 eV) lower than that of the monohydrate. Unlike the situation in the smaller (n⩽13) water cluster anions, the [Gly∙(H2O)n⩾6]− clusters are observed to photodissociate via water monomer evaporation upon photoexcitation in the O–H stretching region. We discuss this observation in the context of the mechanism responsible for the previously observed [S. Xu, M. Nilles, and K. H. Bowen, Jr., J. Chem. Phys. 119, 10696 (2003)] sudden onset in the cluster formation at [Gly∙(H2O)5]−.