bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of mutated transporters associated with antigen‐processing 2 on characteristic major histocompatibility complex binding peptides: analysis using electrospray ionization tandem mass spectrometry
Authors: Kageyama G. , Kawano S. , Kanagawa S. , Kondo S. , Sugita M. , Nakanishi T. , Shimizu A. , Kumagai S.
Published: April 2004

A novel allele of transporters associated with the antigen‐processing (TAP) 2 gene, TAP2*Bky2 (Val577), is significantly increased in Japanese patients with Sjögren's syndrome (SS), and has a strong association with SS‐A/Ro autoantibody production in SS and autoantibody including anti‐SS‐A/Ro and anti‐U1 RNP antibody in systemic lupus erythematosus (SLE). To determine the influence of this natural mutated TAP on peptides loaded onto MHC class I, we analyzed the repertoire of peptides loaded onto MHC class I on transfectants with TAP1 and TAP2 or mutated TAP2 by electrospray ionization tandem mass spectrometry (ESI‐MS/MS). After comparison of the peptide profiles we identified three peptides from only mutated TAP transfectants. Moreover, one of these peptides is derived from snRNP A, which is a target for anti‐U1 RNP antibody. To our knowledge this is the first report to show that the natural mutation of TAP2 changes the peptide profile loaded onto MHC class I molecules. Copyright © 2004 John Wiley & Sons, Ltd.
SPARE Parts: a C++ toolkit for string pattern recognition
Authors: Watson Bruce W. , Cleophas Loek
Published: April 2004

In this paper, we consider the design and implementation of SPARE Parts, a C++ toolkit for pattern matching. SPARE Parts (in particular, the 2003 version presented in this article) is the second generation string pattern matching toolkit by the authors. The toolkit, the first generic program for keyword pattern matching, contains implementations of the well‐known Knuth–Morris–Pratt, Boyer–Moore, Aho–Corasick and Commentz–Walter algorithms (and their variants).

The toolkit is freely available for non‐commercial use. Copyright © 2004 John Wiley & Sons, Ltd.
Abnormal cholinergic and GABAergic vascular innervation in the hypothalamic arcuate nucleus of obese tub/tub mice
Authors: Bäckberg Matilda , Meister Björn
Published: April 2004

Tubby and tubby‐like proteins (TULPs) are encoded by members of a small gene family. An autosomal recessive mutation in the mouse tub gene leads to blindness, deafness, and maturity‐onset obesity. The mechanisms by which the mutation causes the obesity syndrome has not been established. We compared obese tub/tub mice and their lean littermates in order to find abnormalities within the mediobasal hypothalamus, a region intimately associated with the regulation of body weight. Using an antiserum to the vesicular acetylcholine transporter (VAChT), a marker for cholinergic neurons, many unusually large VAChT‐immunoreactive (‐ir) nerve terminals, identified by colocalization with the synaptic vesicle protein synaptophysin, were demonstrated in the hypothalamic arcuate nucleus of obese tub/tub mice. Double‐labeling showed that VAChT‐ir nerve endings also contained glutamic acid decarboxylase (GAD), a marker for γ‐aminobutyric acid (GABA) neurons. The VAChT‐ and GAD‐ir nerve terminals were in close contact with blood vessels, identified with antisera to platelet endothelial cell adhesion molecule‐1 (PECAM; also called CD31), laminin, smooth muscle actin (SMA), and glucose transporter‐1 (GLUT1). Such large cholinergic and GABAergic nerve terminals surrounding blood vessels were not seen in the arcuate nucleus of lean tub/+ mice. The presence of abnormal cholinergic/GABAergic vascular innervation in the arcuate nucleus suggests that alterations in this region, which contains neurons that receive information from the periphery and which relays information about the energy status to other parts of the brain, may be central in the development of the obese phenotype in animals with an autosomal recessive mutation in the tub gene. Synapse 52:245–257, 2004. © 2004 Wiley‐Liss, Inc.
INO® – Oberflächentechnik im Internet. INO® – Surface – Technology in the WWW
Authors: Petrik Marko , Brand Jochen , Schiffmann Kirsten , Fetzer Hans‐Jochen , Gemmler Armin , Schwarz Stefan , Griepentrog Michael , Reiners Georg
Published: April 2004

In den letzten Jahren wurde eine Menge Forschungsarbeit auf dem Gebiet der Oberflächen‐ und Dünnschichttechnologie geleistet, oftmals gefördert durch staatliche Forschungsprogramme, wie zum Beispiel durch das Forschungsprogramm “OSTec”.

Aber die Übertragung dieser großen Menge Wissens in industrielle Anwendungen ist noch ein Problem, weil der Zugang zu diesem Wissen für die Öffentlichkeit oft mit Hindernissen verbunden ist. Es ist kaum möglich einen Überblick zu behalten über alle neuen Entwicklungen. Um dieses Problem zu lösen ist ein neues internetbasiertes Informationssystem entwickelt worden (www.schichttechnik.net).

Es beinhaltet das gesammelte Wissen des “OSTec” – Programms der letzen 10 Jahre und die Daten von Produkten kommerzieller Beschichter. INO® macht das Wissen einer breiten Öffentlichkeit zugänglich.
Geoarchaeological evidence for multidecadal natural climatic variability and ancient Peruvian fisheries
Authors: Sandweiss Daniel H. , Maasch Kirk A. , Chai Fei , Andrus C.Fred T. , Reitz Elizabeth J.
Published: April 2004

Understanding the influence of natural climatic variability on modern fisheries is complicated by over a century of industrial fishing. Archaeological data provide unique opportunities for assessing precolonial and preindustrial fisheries. Records show that anchoveta-vs sardine-dominated fisheries correlate with 20th-century climate change in the Pacific Basin and are linked to multidecadal climatic variability. The “anchovy regime” is characterized by cooler conditions and lower frequency El Niño/Southern Oscillation (ENSO) events, while the “sardine regime” is associated with warmer conditions and higher frequency ENSO. Fish remains excavated at Lo Demás, an Inca-period (ca. A.D. 1480–1540) fishing site at 13°25′S on the Peruvian coast, document a shift from an anchoveta-to a sardine-dominated fishery at about A.D. 1500. This shift correlates with records for increasing ENSO frequency at the same time. Middle and late Holocene sites have archaeofish assemblages that also suggest regime changes. Here we show that changes in fish regimes can result from natural variability and we support the potential role of archaeological assemblages in tracking multidecadal climate change in the Pacific Basin throughout the Holocene (0–11,500 cal yr B.P.).
hNRAGE, a human neurotrophin receptor interacting MAGE homologue, regulates p53 transcriptional activity and inhibits cell proliferation
Authors: Wen Chuan-Jun , Xue Bin , Qin Wen-Xin , Yu Mingyan , Zhang Min-Yue , Zhao Dong-Hong , Gao Xiang , Gu Jian-Ren , Li Chao-Jun
Published: April 2004

hNRAGE, a neurotrophin receptor p75 interacting MAGE homologue, is cloned from a human placenta cDNA library. hNRAGE can inhibit the colony formation of and arrest cell proliferation at the G1/S and G2/M stages in hNRAGE overexpressing cells. Interestingly, hNRAGE also increases the p53 protein level as well as its phosphorylation (Ser392). Further studies demonstrated that hNRAGE does not affect the proliferation of mouse p53−/− embryonic fibroblasts, suggesting that p53 function is required for hNRAGE induced cell cycle arrest. Moreover, the cell cycle inhibiting protein p21WAF is induced by hNRAGE in a p53 dependent manner. The data provide original evidence that hNRAGE arrests cell growth through a p53 dependent pathway.
On the road to immortality: hTERT upregulation in cancer cells
Authors: Janknecht Ralf
Published: April 2004

Telomere attrition limits the replicative potential of most somatic cells. In contrast, tumor cells acquire immortality by continuous telomere maintenance which is predominantly due to the transcriptional upregulation of the limiting component of telomerase, hTERT (human telomerase reverse transcriptase). Recent findings have provided mechanistic insight into how oncogenic activation as well as derepression, often due to the inactivation of tumor suppressors, stimulate the hTERT promoter. Knowledge gained from the study of hTERT transcriptional regulation may prove instrumental in the development of cancer therapies directed at the suppression of telomerase activity in tumor cells.
Thapsigargin‐stimulated MAP kinase phosphorylation via CRAC channels and PLD activation: inhibitory action of docosahexaenoic acid
Authors: Denys Anne , Aires Virginie , Hichami Aziz , Khan Naim Akhtar
Published: April 2004

This study was conducted on human Jurkat T‐cells to investigate the role of depletion of intracellular Ca2+ stores in the phosphorylation of two mitogen‐activated protein kinases (MAPKs), i.e. extracellular signal‐regulated kinase (ERK) 1 and ERK2, and their modulation by a polyunsaturated fatty acid, docosahexaenoic acid (DHA). We observed that thapsigargin (TG) stimulated MAPK activation by store‐operated calcium (SOC) influx via opening of calcium release‐activated calcium (CRAC) channels as tyrphostin‐A9, a CRAC channel blocker, and two SOC influx inhibitors, econazole and SKF‐96365, diminished the action of the former. TG‐stimulated ERK1/ERK2 phosphorylation was also diminished in buffer containing EGTA, a calcium chelator, further suggesting the implication of calcium influx in MAPK activation in these cells. Moreover, TG stimulated the production of diacylglycerol (DAG) by activating phospholipase D (PLD) as propranolol (PROP) (a PLD inhibitor), but not U73122 (a phospholipase C inhibitor), inhibited TG‐evoked DAG production in these cells. DAG production and protein kinase C (PKC) activation were involved upstream of MAPK activation as PROP and GF109203X, a PKC inhibitor, abolished the action of TG on ERK1/ERK2 phosphorylation. Furthermore, DHA seems to act by inhibiting PKC activation as this fatty acid diminished TG‐ and phorbol 12‐myristate 13‐acetate‐induced ERK1/ERK2 phosphorylation in these cells. Together these results suggest that Ca2+ influx via CRAC channels is implicated in PLD/PKC/MAPK activation which may be a target of physiological agents such as DHA.
Loss of palsa mires in Europe and biological consequences
Authors: LUOTO MISKA , HEIKKINEN RISTO K. , CARTER TIMOTHY R.
Published: April 2004

Palsa mires are northern mire complexes with permanently frozen peat hummocks. These are degrading throughout their distribution range, probably because of regional climatic warming. This review of the current understanding of the geographical, climatic and biological characteristics of palsa mires focuses on Europe. Recent studies have reported a drastic decrease in the extent of palsa mires in Fennoscandia; in Finland, the distribution of palsas was formerly about three times that at present. With continued or accelerated warming, as predicted for high latitudes, further extensive degradation or the wholesale disappearance of palsa mires seems inevitable. Palsa mires are known to be biologically heterogeneous environments with a rich diversity of bird species, and they are listed as a priority habitat type by the European Union. However, their role as habitats for other organisms is still poorly understood. There is urgent need for research and monitoring to assess the ecological and biological consequences of the decline of palsa mires in Europe.
Is Viagra a viable conservation tool? Response to Hoover, 2003
Authors: VON HIPPEL WILLIAM , VON HIPPEL FRANK A.
Published: April 2004

In 1998, we (von Hippel & von Hippel 1998) suggested that the advent of Viagra might take some of the market pressure off a variety of threatened species used to treat erectile dysfunction (ED) in traditional Chinese medicine (TCM). In 2002, we (von Hippel & von Hippel 2002) followed up this initial suggestion by providing a more complete analysis of the species that might benefit if TCM consumers switched to Viagra, and we also provided preliminary evidence that the harvest of a few species used in TCM may have already declined due to the availability of Viagra.
Risk coping strategies in tropical forests: floods, illnesses, and resource extraction
Authors: TAKASAKI YOSHITO , BARHAM BRADFORD L. , COOMES OLIVER T.
Published: April 2004

This paper examines coping strategies in response to covariate flood shocks and idiosyncratic health shocks among riverine peasant households in the Amazonian tropical forests. An assessment of coping strategies reveals that although precautionary savings (food stock and livestock) are important for both types of shocks, ex post labor supply responses in the form of upland cropping and resource extraction (fishing and non-timber forest product gathering) are more common to cope with the flood shock depending on local environments. A bivariate probit model examines what factors shape households' adoption decisions of gathering and fishing as a coping strategy. The analysis reveals an important insurance role of non-timber forest product gathering for the asset poor who have limited options for coping with flood risk. Targeted interventions and programs for the poor to promote sustainable forest resource use are discussed.
Rural poverty, household responses to shocks, and agricultural land use: panel results for El Salvador
Authors: RODRÍGUEZ-MEZA JORGE , SOUTHGATE DOUGLAS , GONZÁLEZ-VEGA CLAUDIO
Published: April 2004

This paper addresses factors influencing agricultural land use in rural households in El Salvador, with particular attention paid to the effects of income. Two linkages between the area a household farms and income per capita are critical. First, there is a precautionary demand for land that can be used for subsistence agriculture and this demand declines as income rises. Second, the area a household is able to farm goes up as income increases. Together, these two linkages imply that the relationship between agricultural land use and per capita income takes the shape of an Environmental Kuznets Curve (EKC).

Using panel data collected since 1995 in four biennial surveys of a nationally representative sample of rural households, we have analyzed agricultural land use at the household level. Evidence of an EKC relating farmed area to per capita income has been obtained. In addition, other factors influencing a household's use of natural resources have been examined.
BLACK HEARTS AND MONSTERS OF THE MIND: RACE AND IDENTITY IN ANTEBELLUM AMERICA
Authors: FREDRICKSON GEORGE M.
Published: April 2004

Bruce Dain, A Hideous Monster of the Mind: American Race Theory in the Early Republic (Cambridge, MA: Harvard University Press, 2002)

Patrick Rael, Black Identity and Black Protest in the Antebellum North (Chapel Hill, NC: University of North Carolina Press, 2002)

John Stauffer, The Black Hearts of Men: Radical Abolitionism and the Transformation of Race (Cambridge, MA: Harvard University Press, 2002)
JESUS MATTERS IN THE USA
Authors: HOLLINGER DAVID A.
Published: April 2004

Eugene McCarraher, Christian Critics: Religion and the Impasse in Modern American Social Thought (Ithaca, NY: Cornell University Press, 2000)

D. G. Hart, The Lost Soul of American Protestantism (Lanham, MD: Rowman & Littlefield, 2002)

William R. Hutchison, Religious Pluralism in America: The Contentious History of a Founding Ideal (New Haven, CT: Yale University Press, 2003)

John T. McGreevy, Catholicism and American Freedom: A History (New York: W. W. Norton, 2003)
Understanding and Improving NADPH‐Dependent Reactions by Nongrowing Escherichia coli Cells
Authors: Walton Adam Z. , Stewart Jon D.
Published: April 2004

We have shown that whole Escherichia coli cells overexpressing NADPH‐dependent cyclohexanone monooxygenase carry out a model Baeyer‐Villiger oxidation with high volumetric productivity (0.79 g ϵ‐caprolactone/L·h ) under nongrowing conditions (Walton, A. Z.; Stewart, J. D. Biotechnol. Prog. 2002, 18, 262–268). This is approximately 20‐fold higher than the space‐time yield for reactions that used growing cells of the same strain. Here, we show that the intracellular stability of cyclohexanone monooxygenase and the rate of substrate transport across the cell membrane were the key limitations on the overall reaction duration and rate, respectively. Directly measuring the levels of intracellular nicotinamide cofactors under bioprocess conditions suggested that E. coli cells could support even more efficient NADPH‐dependent bioconversions if a more suitable enzyme‐substrate pair were identified. This was demonstrated by reducing ethyl acetoacetate with whole cells of an E. coli strain that overexpressed an NADPH‐dependent, short‐chain dehydrogenase from bakerapos;s yeast ( Saccharomyces cerevisiae). Under glucose‐fed, nongrowing conditions, this reduction proceeded with a space‐time yield of 2.0 g/L·h and a final product titer of 15.8 g/L using a biocatalyst:substrate ratio (g/g) of only 0.37. These values are significantly higher than those obtained previously. Moreover, the stoichiometry linking ketone reduction and glucose consumption (2.3 ± 0.1) suggested that the citric acid cycle supplied the bulk of the intracellular NADPH under our process conditions. This information can be used to improve the efficiency of glucose utilization even further by metabolic engineering strategies that increase carbon flux through the pentose phosphate pathway.
A Facile and Efficient Method To Achieve LacZ Overproduction by the Expression Vector Carrying the Thermoregulated Promoter and Plasmid Copy Number
Authors: Chao Yun‐Peng , Wen Chih‐Sheng , Wang Jen‐You
Published: April 2004

On the basis of the runaway‐replication vector, an expression plasmid was developed to achieve tight regulation as well as high‐level expression of cloned genes by thermal control of the promoter together with the plasmid copy number. To demonstrate the feasibility of this approach, the lacZ gene was fused with the heat‐inducible promoter on the vector, and the result showed that protein production levels in the Escherichia coli strain harboring the recombinant plasmid could be varied in response to various degrees of heat shock. The maximal soluble LacZ ranging between 45 000 and 50 000 Miller units was obtained as the recombinant strain received a 30 → 40 °C stepwise upshift, and it accounted for a 450‐fold amplification over an uninduced level. Further analyses by SDS‐PAGE indicated the maximal protein production (including soluble and insoluble forms) in the bacteria reaching approximately 30% total cell protein. In addition, two approaches were demonstrated to be very useful in enhancing the total soluble LacZ production on a fermenter scale. One was to shuttle the culture between two fermenters connected in series and set at different temperatures. The other resorted to the use of two‐step temperature alteration in a batch fermenter, namely, raising the temperature to 40 °C for a certain period of time followed by reducing the temperature to 37 °C. Overall, it illustrates the remarkable features of the expression system with stringent regulation, high‐level production capacity, facile induction, and high stability, and the usefulness of this system for recombinant protein productions is promising.
Catalytic Properties of d‐Amino Acid Oxidase in Cephalosporin C Bioconversion: A Comparison between Proteins from Different Sources
Authors: Pollegioni Loredano , Caldinelli Laura , Molla Gianluca , Sacchi Silvia , Pilone Mirella S.
Published: April 2004

Lacking an efficient process to produce 7‐aminocephalosporanic acid from cephalosporin C in a single step, d‐amino acid oxidase (DAAO) is of foremost importance in the industrial, two‐step process used for this purpose. We report a detailed study on the catalytic properties of the three available DAAOs, namely, a mammalian DAAO and two others from yeast ( Rhodotorula gracilisand Trigonopsis variabilis). In comparing the kinetic parameters determined for the three DAAOs, with both cephalosporin C and d‐alanine as substrate, the catalytic efficiency of the two enzymes from microorganism is at least 2 orders of magnitude higher than that of pig kidney DAAO. Furthermore, the mammalian enzyme is more sensitive to product inhibition (from hydrogen peroxide and glutaryl‐7‐aminocephalosporanic acid). Therefore, enzymes from microorganisms appear to be by far more suitable catalysts for bioconversion, although some different minor differences are present between them (e.g., a higher activity of the R. gracilisenzyme when the bioconversion is carried out at saturating oxygen concentration). The mammalian DAAO, even being a poor catalyst, is more stable with respect to temperature than the R. gracilis enzyme in the free form. In any case, for industrial purposes DAAO is used only in the immobilized form where a strong enzyme stabilization occurs.
Maximizing Recovery of Native Protein from Aggregates by Optimizing Pressure Treatment
Authors: Lefebvre Brian G. , Gage Matthew J. , Robinson Anne Skaja
Published: April 2004

Recovering native protein from aggregates is a common obstacle in the production of recombinant proteins. Recent reports have shown that hydrostatic pressure is an attractive alternative to traditional denature‐and‐dilute techniques, both in terms of yield and process simplicity. To determine the effect of process variables, we subjected tailspike aggregates to a variety of pressure‐treatment conditions. Maximum native tailspike yields were obtained with only short pressure incubations (<5 min) at 240 MPa. However, some tailspike aggregates were resistant to pressure, despite multiple cycles of pressure. Extending the postpressure incubation time to 4 days improved the yield of native protein from aggregates from 19.4 ± 0.9 to 47.4 ± 19.6 μg/mL (approximately 78% yield of native trimer from nonaggregate material). The nearly exclusive conversion of monomer to trimer over the time scale of days, when combined with previous kinetic data, allows for the identification of three postpressure kinetic phases: a rapid phase consisting of structured dimer conversion to trimer (30 min), an intermediate phase consisting of monomer conversion to aggregate (100 min), and a slow phase consisting of conversion of monomer to trimer (days). Optimizing the production of structured dimer can yield the highest level of folded protein. Typical refolding additives, such as glycerol, or low‐temperature incubation did not improve yields.
Incorporation of 3T3‐L1 Cells To Mimic Bioaccumulation in a Microscale Cell Culture Analog Device for Toxicity Studies
Authors: Viravaidya Kwanchanok , Shuler Michael L.
Published: April 2004

Deficiencies in the early ADMET (absorption, distribution, metabolism, elimination, and toxicity) information on drug candidates extract a significant economic penalty on pharmaceutical firms. We have developed a microscale cell culture analog (μCCA) device that can potentially provide better, faster, and more efficient prediction of human and animal responses to a wide range of chemicals. The system described in this paper is a simple four‐chamber μCCA (“lung”–“liver”–“fat”–“other tissue”) designed on the basis of a physiologically based pharmacokinetics (PBPK) model of a rat. Cultures of L2, HepG2/C3A, and differentiated 3T3‐L1 adipocytes were selected to mimic the key functions of the lung, liver, and fat compartments, respectively. Here, we have demonstrated the application of the μCCA system to study bioaccumulation, distribution, and toxicity of selected compounds. Results from the bioaccumulation study reveal that hydrophobic compounds such as fluoranthene preferentially accumulated in the fat chamber. Only a small amount of fluoranthene was observed in the liver and lung chambers. In addition, the presence of the differentiated 3T3‐L1 adipocytes in the μCCA device significantly reduced naphthalene and naphthoquinone‐induced glutathione (GSH) depletion. These findings suggest the potential utilization of the μCCA system to assess ADMET characteristics of the compound of interest prior to animal or human trials.
Hydrolysis of Nonstarch Carbohydrates of Wheat‐Starch Effluent for Ethanol Production
Authors: Palmarola‐Adrados Beatriz , Juhász Tamás , Galbe Mats , Zacchi Guido
Published: April 2004

A (polysaccharide‐rich) waste stream derived from a combined starch and ethanol factory was investigated regarding hydrolysis of the nonstarch carbohydrates for ethanol production. The material was characterized and processed to yield the maximum amount of sugars. The starch fraction was hydrolyzed with amylolytic enzymes, and the resulting fibrous material was separated by filtration. This material, denoted starch‐free fibers (SFF), was subjected to heat treatment followed by enzymatic hydrolysis to recover the other major carbohydrate components, namely, cellulose and hemicellulose, in monomeric form. Heat treatment in a microwave oven efficiently solubilized a fraction of these polysaccharides and made the material more accessible to the cellulolytic and hemicellulolytic enzymes used in the subsequent enzymatic hydrolysis. The maximum sugar yield after enzymatic hydrolysis, achieved with pretreatment at 170 °C for 40 min, was 34.1 g per 100 g SFF, comprising 12.8 g glucose, 13.9 g xylose and 7.4 g arabinose, corresponding to 66%, 71% and 51% of the theoretical, respectively.
Determination of Viable Yeast Cells by Gravitational Field‐Flow Fractionation with Fluorescence Detection
Authors: Sanz R. , Galceran M. T. , Puignou L.
Published: April 2004

Vinification processing is largely related to yeast performance and depends on the initial cell viability. To optimize the quality of wine fermentation, control of the yeast quality is mandatory. The present paper describes a new method using gravitational field flow fractionation (GrFFF) with fluorescence detection for the determination of yeast cell viability before the fermentation process. A GrFFF calibration procedure was developed using commercial yeast to prepare standards of viable cells and propidium iodide (PI) as fluorescent probe for nonviable cells. The suitability of the new method was tested with several commercial yeast strains with a g/L content ranging from 1 to 3. The validation of the method was performed by comparing GrFFF viability values with those obtained using Coulter counter and flow cytometry techniques.
The Importance of the Keyword-Generation Method in Keyword Mnemonics
Authors: Campos Alfredo , Amor Angeles , González María Angeles
Published: April 2004

Abstract. Keyword mnemonics is under certain conditions an effective approach for learning foreign-language vocabulary. It appears to be effective for words with high image vividness but not for words with low image vividness. In this study, two experiments were performed to assess the efficacy of a new keyword-generation procedure (peer generation). In Experiment 1, a sample of 363 high-school students was randomly divided into four groups. The subjects were required to learn L1 equivalents of a list of 16 Latin words (8 with high image vividness, 8 with low image vividness), using a) the rote method, or the keyword method with b) keywords and images generated and supplied by the experimenter, c) keywords and images generated by themselves, or d) keywords and images previously generated by peers (i.e., subjects with similar sociodemographic characteristics). Recall was tested immediately and one week later. For high-vividness words, recall was significantly better in the keyword groups than the rote method group. For low-vividness words, learning method had no significant effect. Experiment 2 was basically identical, except that the word lists comprised 32 words (16 high-vividness, 16 low-vividness). In this experiment, the peer-generated-keyword group showed significantly better recall of high-vividness words than the rote method groups and the subject generated keyword group; again, however, learning method had no significant effect on recall of low-vividness words.
Generation, transport, and preservation of the alkenone‐based U37K′ sea surface temperature index in the water column and sediments of the Cariaco Basin (Venezuela)
Authors: Goni Miguel A. , Woodworth Mark P. , Aceves Heather L. , Thunell Robert C. , Tappa Eric , Black David , Müller‐Karger Frank , Astor Yrene , Varela Ramon
Published: April 2004

Alkenone fluxes in the water column of the Cariaco Basin ranged from 12 to 20 μg m−2 d−1 and were inversely related to upwelling strength. The U37K′ ratios of sinking particles varied from 0.78 to 0.96 and exhibited seasonal changes that were coherent with a 7°C variation in sea surface temperature (SST). The correlation between SST and U37K′ ratios closely overlapped with the calibration of Prahl et al. [1988]. Alkenone burial fluxes in Cariaco Basin sediments varied markedly over the past ∼6000 years, ranging from 0.2 to 5 μg m−2 d−1. The U37K′ ratios of surface sediments indicate SST was higher (26.3°C) during the last 50 years of deposition than in the previous 300 years (∼25°C), signaling an upwelling decrease in the latter part of the twentieth century. The lowest U37K′‐derived temperatures (∼25°C) were measured in sediments deposited during the little ice age (LIA). These compositions, coupled with relatively low alkenone fluxes (≤2 μg m−2 d−1), are consistent with conditions of enhanced upwelling, decreased SST and reduced haptophyte production. The highest U37K′‐derived SST estimates (over 26.5°C) were measured during the Medieval Warm Period (MWP) and suggest reduced upwelling at this time. Prior to the MWP, the alkenone record indicates temperatures of ∼26°C and burial fluxes of ∼2 μg m−2 d−1. These compositions indicate stronger upwelling conditions during the Holocene relative to the last 50 years and the MWP but annual SSTs above those estimated for the LIA.
Auroral ion acceleration in dispersive Alfvén waves
Authors: Chaston C. C. , Bonnell J. W. , Carlson C. W. , McFadden J. P. , Ergun R. E. , Strangeway R. J. , Lund E. J.
Published: April 2004

Observations from the FAST satellite are used to create a model for dispersive Alfvén waves above the auroral oval. Using this model, it is shown how these waves may accelerate ionospheric ions transverse to the geomagnetic field and cause ion outflow. The model waves grow from ionospheric conductivity variations due to auroral electron precipitation and resonate in the cavity between the ionosphere and the peak in the Alfvén speed that occurs at altitudes of ∼1 Earth radius (Re). By tracing ions in the model wave field, it is demonstrated that for transverse wave amplitudes (E⊥) satisfying E⊥/Bo < Ωi/k⊥ (where Bo is the geomagnetic field strength, k⊥ is the perpendicular wave number, and Ωi is the ion gyrofrequency) the ion motion in the wave field is coherent and the ions may become trapped in the transverse wave potential. In Alfvén waves having two‐dimensional structure transverse to Bo, these ions may be accelerated up to a transverse energy that provides an ion gyrodiameter roughly equivalent to the perpendicular scale or wavelength (λ⊥) of the wave. Alternatively, when E⊥/Bo > Ωi/k⊥ the ion motion may become stochastic allowing acceleration to energies exceeding that prescribed by λ⊥. The transversely accelerated ions in both the coherent and stochastic cases flow upward from the ionosphere under the influence of the mirror force to altitudes of 1 Earth radii over timescales as small as a few seconds to minutes with energies in the keV range. Ions accelerated by these means may account for the intense outflowing ion fluxes observed in Alfvén waves above the auroral oval.
Sawtooth oscillations directly driven by solar wind dynamic pressure enhancements
Authors: Lee D.‐Y. , Lyons L. R. , Yumoto K.
Published: April 2004

We have examined four well‐defined events of sawtooth oscillations in energetic particle flux and magnetic field at geosynchronous orbit. During all four events, nearly simultaneous energetic particle flux enhancements and magnetic field variations occurred at all MLTs for each sawtooth cycle. Geomagnetic H component data at low to middle latitude also show a global H increase simultaneously with the geosynchronous responses at all MLTs, and the northern and southern PC indices generally show increases at each sawtooth cycle. All these are what is expected if solar wind pressure enhancements impacted the magnetosphere at times appropriate to have caused the onset of each sawtooth cycle. By directly checking the solar wind data, we find that there indeed exists a series of solar wind dynamic pressure enhancements for each sawtooth event. In identifying these pressure enhancements, we have found that the relative change in the dynamic pressure is important, particularly when the magnitude of the dynamic pressure is small and that even a modest dynamic pressure enhancement can result in significant changes in the magnetosphere when the IMF stays strongly southward for a long interval. We show that each cycle of the sawtooth oscillation can be reasonably associated in timing with a corresponding solar wind dynamic pressure enhancement. On the basis of this association and the global, simultaneous geosynchronous and ground responses, we suggest that the sawtooth oscillations studied in this paper are directly driven by series of solar wind pressure enhancements and are not a repetitive internal magnetospheric response to sustained enhanced solar wind energy input.
Glacial ventilation rates for the deep Pacific Ocean
Authors: Broecker Wallace S. , Clark Elizabeth , Hajdas Irena , Bonani Georges
Published: April 2004

A key constraint in attempts to reconstruct the patterns and rates of the ocean's thermohaline circulation during the last glacial period is the difference between the 14C to C ratio in surface and deep water. While imperfect, it is our best index of past deep‐sea ventilation rates. In this paper we review published ventilation rate estimates based on the measured radiocarbon age difference between coexisting benthic and planktic foraminifera from glacial‐age Pacific sediments. We also present new results from a series of eastern equatorial Pacific sediment cores. The conclusion is that the scatter in these results is so large that the apparent 14C age of glacial deep Pacific water could lie anywhere between double and half today's. Further, it is not clear what is responsible for the wide scatter in the radiocarbon results.
On the receiving cross section of an antenna in infinite linear and planar arrays
Authors: Craeye C. , Arts M.
Published: April 2004

A rigorous derivation is given for the receiving cross section of an antenna located in infinite linear and planar arrays. For linear arrays the result involves the active input impedance and the azimuthal directivity of the array. For planar arrays it depends on the active input impedance and on geometrical parameters of the array. The expression of the receiving cross section of an element can be used to derive the generally accepted expression for the active element pattern without, however, making use of intuitive arguments. Results are first presented for conditions without grating lobes; they are then generalized to conditions where grating lobes enter the visible space.
Bathymetry of Mariana trench‐arc system and formation of the Challenger Deep as a consequence of weak plate coupling
Authors: Gvirtzman Zohar , Stern Robert J.
Published: April 2004

The Challenger Deep in the southernmost Mariana Trench (western Pacific Ocean) is the deepest point on the Earth's surface (10,920 m below sea level). Its location within a subduction trench, where one plate bends and descends below another, is not surprising. However, why is it located in the southernmost Mariana Trench and not at its central part, where the rate of subduction is higher, where the lithosphere is the oldest (and densest) on the Earth, and where the subducted lithosphere pulling down is the longest in the Earth (∼1000 km or more according to seismic tomography)? We suggest that although subduction rate and slab age generally control trench depth, the width of the plate‐coupling zone is more important. Beneath the central Marianas the subducted slab is attached to the upper plate along a 150‐km‐wide surface that holds the shallow portion of the subducted plate nearly horizontal, in spite of its great load and, thus, counters trench deepening. In contrast, along the south Mariana Trench the subducted length of the lithosphere is much shorter, but its attachment to the upper plate is only along a relatively narrow, 50‐km‐wide, surface. In addition, a tear in the slab beneath this region helps it to sink rapidly through the mantle, and this combination of circumstances allows the slab to steepen and form the deepest trench on the Earth. In a wider perspective, the interrelations shown here between trench deepening, ridge shallowing, slab steepening, and forearc narrowing may shed light on other subduction zones located near edges of rapidly steepening slabs.
A stochastic partial transport model for mixed‐size sediment: Application to assessment of fractional mobility
Authors: Wu Fu‐Chun , Yang Kuo‐Hsin
Published: April 2004

In this study we incorporate the existing concept of fractional mobility into a stochastic framework for modeling the partial transport of mixed‐size sediment. The model predicts the fractional transport rates with parameters such as the long‐run moving probability, mean particle velocity, and fractional mobility, all varying with the dimensionless effective shear stress. Movement of bed load particles is treated as a random combination of single‐step motions described by the pseudo four‐state continuous‐time Markov process whose long‐run moving probability can be evaluated with the instantaneous entrainment probability and ratio of mean single‐step holding time. A most updated version of entrainment probability taking into account both the rolling and lifting modes is adopted; the ratio of mean holding time is determined with a physically based relation derived experimentally. Two types of experiments are performed in this study: the colored bed experiments are carried out to observe the fractional mobility and partial transport; the plain bed experiments are conducted to observe the single‐step bed load motions and mean particle velocity. The proposed model is widely tested with laboratory and field data pertaining to both partial and full transport conditions, and reasonably good agreement between the predicted and observed results is demonstrated. The model is then applied to evaluate the fractional mobility and explore the influence of sand content. The results reveal that the relation between fractional mobility and dimensionless effective shear stress is well approximated by the cumulative lognormal distribution, with its mean and standard deviation linearly decreasing with sand content for the range <0.34. The results imply that the existence of fine‐grained sand in the gravel‐sand mixture is favorable to the mobilization of sediment. At higher sand content the condition of partial transport exists within a narrower range of flows such that full transport is easier to achieve. The present study is the first to investigate the effect of sand content on the fractional mobility, thus providing new insights into the process of partial transport.
Type‐curve estimation of statistical heterogeneity
Authors: Neuman Shlomo P. , Guadagnini Alberto , Riva Monica
Published: April 2004

The analysis of pumping tests has traditionally relied on analytical solutions of groundwater flow equations in relatively simple domains, consisting of one or at most a few units having uniform hydraulic properties. Recently, attention has been shifting toward methods and solutions that would allow one to characterize subsurface heterogeneities in greater detail. On one hand, geostatistical inverse methods are being used to assess the spatial variability of parameters, such as permeability and porosity, on the basis of multiple cross‐hole pressure interference tests. On the other hand, analytical solutions are being developed to describe the mean and variance (first and second statistical moments) of flow to a well in a randomly heterogeneous medium. We explore numerically the feasibility of using a simple graphical approach (without numerical inversion) to estimate the geometric mean, integral scale, and variance of local log transmissivity on the basis of quasi steady state head data when a randomly heterogeneous confined aquifer is pumped at a constant rate. By local log transmissivity we mean a function varying randomly over horizontal distances that are small in comparison with a characteristic spacing between pumping and observation wells during a test. Experimental evidence and hydrogeologic scaling theory suggest that such a function would tend to exhibit an integral scale well below the maximum well spacing. This is in contrast to equivalent transmissivities derived from pumping tests by treating the aquifer as being locally uniform (on the scale of each test), which tend to exhibit regional‐scale spatial correlations. We show that whereas the mean and integral scale of local log transmissivity can be estimated reasonably well based on theoretical ensemble mean variations of head and drawdown with radial distance from a pumping well, estimating the log transmissivity variance is more difficult. We obtain reasonable estimates of the latter based on theoretical variation of the standard deviation of circumferentially averaged drawdown about its mean.
Status quo analysis of the Flathead River conflict
Authors: Li Kevin W. , Kilgour D. Marc , Hipel Keith W.
Published: April 2004

Status quo analysis algorithms developed within the paradigm of the graph model for conflict resolution are applied to an international river basin conflict involving the United States and Canada to assess the likeliness of various compromise resolutions. The conflict arose because the state of Montana feared that further expansion of the Sage Creek Coal Company facilities in Canada would pollute the Flathead River, which flows from British Columbia to Montana. Significant insights not generally available from a static stability analysis are obtained about potential resolutions of the conflict under study and about how decision makers' interactions may direct the conflict to distinct resolutions. Analyses also show how political considerations may affect a particular decision maker's choice, thereby influencing the evolution of the conflict.
Interaction of a novel dihydropyridine K+ channel opener, A‐312110, with recombinant sulphonylurea receptors and KATP channels: comparison with the cyanoguanidine P1075
Authors: Felsch Holger , Lange Ulf , Hambrock Annette , Löffler‐Walz Cornelia , Russ Ulrich , Carroll William A , Gopalakrishnan Murali , Quast Ulrich
Published: April 2004

ATP‐sensitive K+ channels (KATP channels) are composed of pore‐forming subunits (Kir6.x) and of regulatory subunits, the sulphonylurea receptors (SURx). Synthetic openers of KATP channels form a chemically heterogeneous class of compounds that are of interest in several therapeutic areas. We have investigated the interaction of a novel dihydropyridine opener, A‐312110 ((9R)‐9‐(4‐fluoro‐3‐iodophenyl)‐2,3,5,9‐tetrahydro‐4H‐pyrano[3,4‐b]thieno [2,3‐e]pyridin‐8(7H)‐one‐1,1‐dioxide), with SURs and Kir6/SUR channels in comparison to the cyanoguanidine opener P1075.

In the presence of 1 mM MgATP, A‐312110 bound to SUR2A (the SUR in cardiac and skeletal muscle) and to SUR2B (smooth muscle) with Ki values of 14 and 18 nM; the corresponding values for P1075 were 16 and 9 nM, respectively. Decreasing the MgATP concentration reduced the affinity of A312110 binding to SUR2A significantly more than that to SUR2B; for P1075, the converse was true. At SUR1 (pancreatic β‐cell), both openers showed little binding up to 100 μM.

In the presence of MgATP, both openers inhibited [3H]glibenclamide binding to the SUR2 subtypes in a biphasic manner. In the absence of MgATP, the high‐affinity component of the inhibition curves was absent.

In inside‐out patches, the two openers activated the Kir6.2/SUR2A and Kir6.2/SUR2B channels with similar potency (∼50 nM). Both were almost 2 × more efficacious in opening the Kir6.2/SUR2B than the Kir6.2/SUR2A channel.

The results show that the novel dihydropyridine A‐312110 is a potent KATP channel opener with binding and channel‐opening properties similar to those of P1075.

British Journal of Pharmacology (2004) 141, 1098–1105. doi:10.1038/sj.bjp.0705718
4‐Bromo‐2,5‐dimethoxyphenethylamine (2C‐B) and structurally related phenylethylamines are potent 5‐HT2A receptor antagonists in Xenopus laevis oocytes
Authors: Villalobos Claudio A , Bull Paulina , Sáez Patricio , Cassels Bruce K , Huidobro‐Toro J Pablo
Published: April 2004

We recently described that several 2‐(2,5‐dimethoxy‐4‐substituted phenyl)ethylamines (PEAs), including 4‐I=2C‐I, 4‐Br=2C‐B, and 4‐CH3=2C‐D analogs, are partial agonists at 5‐HT2C receptors, and show low or even negligible intrinsic efficacy at 5‐HT2A receptors. These results raised the proposal that these drugs may act as 5‐HT2 antagonists.

To test this hypothesis, Xenopus laevis oocytes were microinjected with the rat clones for 5‐HT2A or 5‐HT2C receptors. The above‐mentioned PEAs and its 4‐H analog (2C‐H) blocked the 5‐HT‐induced currents at 5‐HT2A, but not at the 5‐HT2C receptor, revealing 5‐HT2 receptor subtype selectivity. The 5‐HT2A receptor antagonism required a 2‐min preincubation to attain maximum inhibition.

All PEAs tested shifted the 5‐HT concentration–response curves to the right and downward. Their potencies varied with the nature of the C(4) substituent; the relative rank order of their 5‐HT2A receptor antagonist potency was 2C‐I>2C‐B>2C‐D>2C‐H.

The present results demonstrate that in X. laevis oocytes, a series of 2,5‐dimethoxy‐4‐substituted PEAs blocked the 5‐HT2A but not the 5‐HT2C receptor‐mediated responses. As an alternative hypothesis, we suggest that the psychostimulant activity of the PEAs may not be exclusively associated with partial or full 5‐HT2A receptor agonism.

British Journal of Pharmacology (2004) 141, 1167–1174. doi:10.1038/sj.bjp.0705722
Spectroscopic investigation of nonbonding interactions of group-14 atoms with rare gases: The SnAr van der Waals complex
Authors: Tao Chong , Dagdigian Paul J.
Published: April 2004

The laser fluorescence excitation spectra of the SnAr van der Waals complex, in the vicinity of the individual fine-structure lines of the Sn 5s25p6s 3P0 ← 5s25p2 3P atomic resonance transition in the spectral region 317–270 nm are reported. Excited-state (v′,0) progressions of bands built upon the individual J′← J″ fine-structure atomic lines were observed. Because the collisional spin–orbit relaxation was slow, transitions were observed out of the lower SnAr states built upon all the J″ atomic asymptotes. The spectra were interpreted through model potential energy curves based on the isoelectronic SiAr system. Lower bounds to the dissociation energies of all lower SnAr states were determined. The binding energies of the group-13, and -14-atom–argon complexes and the effect of the spin–orbit interaction on moderating nonbonding interactions are discussed.
Analytic evaluation of nonadiabatic coupling terms at the MR-CI level. I. Formalism
Authors: Lischka Hans , Dallos Michal , Szalay Péter G. , Yarkony David R. , Shepard Ron
Published: April 2004

An efficient and general method for the analytic computation of the nonandiabatic coupling vector at the multireference configuration interaction (MR-CI) level is presented. This method is based on a previously developed formalism for analytic MR-CI gradients adapted to the use for the computation of nonadiabatic coupling terms. As was the case for the analytic energy gradients, very general, separate choices of invariant orbital subspaces at the multiconfiguration self-consistent field and MR-CI levels are possible, allowing flexible selections of MR-CI wave functions. The computational cost for the calculation of the nonadiabatic coupling vector at the MR-CI level is far below the cost for the energy calculation. In this paper the formalism of the method is presented and in the following paper [Dallos et al., J. Chem. Phys. 120, 7330 (2004)] applications concerning the optimization of minima on the crossing seam are described.