bluuebunny/crossref_metadata_2025 huggingface dataset:
The cyclization of peptides and depsipeptides
Authors: Davies John S.
Published: August 2003

Constricting the peptide backbone into a more defined conformational form through cyclization is an activity evolved in nature and in synthetic work, the latter straddling only the most recent decades. The resulting conformational constraints increase the probability of an optimum response with bio‐receptors. The purpose of this review is to highlight developments that have proved to be reasonably efficient in the macrocyclization of linear precursors into cyclic peptides and depsipeptides. Copyright © 2003 European Peptide Society and John Wiley & Sons, Ltd.
One‐particle density matrix functional for correlation in molecular systems
Authors: Piris Mario , Otto Peter
Published: August 2003

Based on the analysis of the general properties for the one‐ and two‐particle reduced density matrices, a new natural orbital functional is obtained. It is shown that by partitioning the two‐particle reduced density matrix in an antisymmeterized product of one‐particle reduced density matrices and a correction Γc we can derive a corrected Hartree–Fock theory. The spin structure of the correction term from the improved Bardeen–Cooper–Schrieffer theory is considered to take into account the correlation between pairs of electrons with antiparallel spins. The analysis affords a nonidempotent condition for the one‐particle reduced density matrix. Test calculations of the correlation energy and the dipole moment of several molecules in the ground state demonstrate the reliability of the formalism. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem 94: 317–323, 2003
Professional influence: the effects of investment banks on clients' acquisition financing and performance
Authors: Hayward Mathew L. A.
Published: August 2003

This study examines the conditions in which professional firms use client engagements to get clients to subsequently hire them. The central thesis is that professional firms derive power from their specialized expertise and lead clients towards complex problems that apply the expertise. In particular, relative to cash‐financed acquisitions, stock‐financed acquisitions more intensively apply investment banks' expertise. Consistent with expectations, results from a sample of 404 acquisitions show that firms are more likely to hire banks on stock‐financed acquisitions when they have previously used banks. Evidence also suggests that clients that hire banks on such acquisitions are prone to adverse performance from them. Overall, these results suggest that professional firms lead clients to complex solutions with problematic outcomes. Copyright © 2003 John Wiley & Sons, Ltd.
An empirical examination of transaction‐ and firm‐level influences on the vertical boundaries of the firm
Authors: Leiblein Michael J. , Miller Douglas J.
Published: August 2003

A large literature has successfully employed transaction cost economic theory to describe how exchange conditions affect the optimal form of organization. However, this approach has historically not accounted for the influence of firm‐specific attributes on the governance decision. This paper develops a model based on insights from transaction cost economics, the resource‐based view, and real options theory to examine how transaction‐level characteristics, firm‐specific capabilities, and product‐market scope influence the governance of production. Empirical evidence derived from analysis of 469 make‐or‐buy decisions involving 117 semiconductor firms indicates that decisions regarding the governance of production activities are strongly influenced by both transaction‐ and firm‐level effects. Copyright © 2003 John Wiley & Sons, Ltd.
Software product line migration and deployment
Authors: Faust D , Verhoef C
Published: August 2003

We describe a method to migrate multiple instances of a successful single information system to a product line. The deployed product line is able to deal with the variants evolved over time in a cost‐effective manner. We proposed and used federated architectures that partition the software into so‐called genericity layers. We argue that federated architectures are at the heart of product lines, and we provide compelling arguments as to why federated architectures are a sound weapon in today's corporate strategy: they enable smooth enterprise integration and rapid change. We support our arguments with a real‐world case: we successfully migrated a large global transaction and settlement system with many site‐specific variations to a product line with a federated architecture. Moreover, we measured the success rate of this architectural modification effort by showing that the annual direct cost savings are of the order of millions of dollars during the deployment of the product line. Copyright © 2003 John Wiley & Sons, Ltd.
Explaining code for publication
Authors: Thimbleby Harold
Published: August 2003

The computer science literature discusses code and algorithms extensively, but not always reliably. Tool support can help ensure integrity between code and explanation so that published papers are more reliable.

A versatile, lightweight tool to support explaining code for publication is justified, described and compared with alternatives. The tool works with Java, C and similar languages, and provides support for publishing explanations of real code in LATEX, XML, HTML, etc. Copyright © 2003 John Wiley & Sons, Ltd.
Gabapentin actions on Kir3 currents and N‐type Ca2+ channels via GABAB receptors in hippocampal pyramidal cells
Authors: Bertrand Sandrine , Nouel Dominique , Morin France , Nagy Frédéric , Lacaille Jean‐Claude
Published: August 2003

Gabapentin is a clinically effective anticonvulsant with an unclear mechanism of action. It was described as a GABAB(1a,2) receptor subtype‐selective agonist, activating postsynaptic K+ currents and inhibiting postsynaptic Ca2+ channels in CA1 pyramidal cells, but without presynaptic actions. These activities appeared controversial and we therefore sought to further clarify gabapentin actions in rat hippocampal slices by characterizing K+ currents and Ca2+ channels targeted by gabapentin using whole‐cell recording and multiphoton Ca2+ imaging. 1) We found that gabapentin and baclofen induced inwardly rectifying K+ currents (KGbp and KBac, respectively), sensitive to Ba2+ and Cs+. 2) A constitutively active KIR current, independent of GABAB receptor activation and sensitive to Ba2+ and Cs+ was also present. 3) KGbp, KBac, and KIR currents showed some differences in sensitivity to Ba2+ and Cs+, indicating the possible activation of distinct Kir3 currents, independent of KIR, by gabapentin and baclofen. 4) Gabapentin inhibition of Ca2+ channels was abolished by ω‐conotoxin GVIA, but not by ω‐agatoxin IVA and nimodipine, indicating a predominant action of gabapentin on N‐type Ca2+ channels. 5) Gabapentin actions were linked to activation of pertussis toxin‐sensitive G‐proteins since N‐ethylmaleimide (NEM) blocked KGbp activation and Ca2+ channel inhibition by gabapentin. 6) Finally, gabapentin reduced epileptiform discharges in slices via GABAB receptor activation. The anticonvulsant actions of gabapentin in hippocampal cells may thus involve GABAB receptor coupling to G‐proteins and modulation of Kir3 and N‐type Ca2+ channels. Moreover, gabapentin and baclofen activation of GABAB receptors may couple to distinct cellular targets. Synapse 50:95–109, 2003. © 2003 Wiley‐Liss, Inc.
Pharmacokinetic and pharmacodynamic analyses, based on dopamine D2‐receptor occupancy of bromocriptine, of bromocriptine‐induced contralateral rotations in unilaterally 6‐OHDA‐lesioned rats
Authors: Atsumi Masako , Kawakami Junichi , Sugiyama Erika , Kotaki Hajime , Sawada Yasufumi , Sato Hitoshi , Yamada Yasuhiko , Iga Tatsuji
Published: August 2003

Bromocriptine is a selective agonist for dopamine D2‐receptors and is used in the treatment of Parkinson's disease. In this study, we performed pharmacokinetic and pharmacodynamic (PK/PD) analyses of the antiparkinsonian effect of bromocriptine and evaluated drug‐induced contralateral rotations in rats in which unilateral striatal lesions had been generated by microinjection of 6‐hydroxydopamine (6‐OHDA) into the medial forebrain bundle. The plasma concentration (Cp) and D2‐receptor occupancy (ΦD2) were quantitated by HPLC and with an in vivo back‐titration method using [3H]‐raclopride, respectively. Bromocriptine induced contralateral rotations (Erot) in a dose‐dependent manner following intraperitoneal administration in an animal model of Parkinson's disease. The Cp of bromocriptine peaked at 15–30 min after the administration and decreased time‐dependently, whereas the ΦD2 of bromocriptine increased gradually for 180 min after administration. The relationship between Cp and Erot exhibited an anticlockwise hysteresis, whereas the relationship between ΦD2 and Erot showed a linear correlation. These results suggest that in vivo ΦD2 is a good pharmacological indicator of the effect of a D2 agonist. Synapse 50:110–116, 2003. © 2003 Wiley‐Liss, Inc.
Reversal of pentylenetetrazol‐induced potentiation phenomenon by theta pulse stimulation in the CA1 region of rat hippocampal slices
Authors: Omrani Azar , Fathollahi Yaghoub
Published: August 2003

The effect of theta pulse stimulation (TPS) on pentylenetetrazol (PTZ)‐induced long‐term potentiation of population spikes was studied in the CA1 region of rat hippocampal slices. The field excitatory postsynaptic potential (fEPSP) and population spikes (PS) were recorded from strata radiatum and pyramidale, respectively, following stimulation of Schaffer collaterals. A transient PTZ application produced a long‐lasting enhancement of PS amplitude. A 3‐min episode of TPS delivered at test‐pulse intensity failed to reverse the PTZ potentiation. However, the same stimulation at a higher intensity produced complete reversal of the PTZ potentiation when delivered during the last minutes of PTZ application. Prior application of high‐intensity TPS also decreased the amount of PTZ potentiation, whereas it had no long‐lasting effect on baseline synaptic responses. High‐intensity TPS induced reversal was blocked by adenosine A1 receptor antagonist and, furthermore, was reduced by protein phosphatase 1 inhibitor. The results suggest that mechanism of PTZ‐induced LTP reversal involves activation of adenosine receptors and protein phosphatases. Synapse 50:83–94, 2003. © 2003 Wiley‐Liss, Inc.
Martin Associates Group
Authors: Martin John A. , Schindler Barry S.
Published: August 2003

Founded in 1953 in Los Angeles, California, by John A. ‘Jack’ Martin as his namesake with a core group of just three structural engineers, Martin Associates Group, Inc. today has a professional staff of over 450 disseminated throughout 16 offices extending from the Pacific Rim all the way to Missouri. The largest of these offices are in Los Angeles, Denver, and Las Vegas. The firm's engineers are licensed to practice in all 50 states and the province of Guam. Jack Martin is still actively involved in the day‐to‐day operations of all the offices as the CEO of the Martin Organization, while his son, John A. ‘Trailer’ Martin Jr has been with the firm for 33 years and has been the President of John A. Martin & Associates, Inc. for about the last 20 of those years. Copyright © 2003 John Wiley & Sons, Ltd.
Brandow & Johnston Associates
Authors: Brandow Gregg E.
Published: August 2003

This history of the structural engineering firm Brandow & Johnston Associates is a history of the founding principals and a legacy of projects from small to large, short to tall, and structurally simple to structurally challenging. Selected buildings have been chosen and presented because they were unique at the time of construction, impressive architecturally, or significant structurally. Copyright © 2003 John Wiley & Sons, Ltd.
AC Martin Partners
Authors: Martin David C. , Tahtakran Onik
Published: August 2003

AC Martin Partners, Inc. (ACMP) is an integrated architecture, engineering, and planning firm with a long‐standing tradition of creating environments that have had significant impacts upon their surroundings through craft, integrity, and social responsibility. This paper describes several of their projects. Copyright © 2003 John Wiley & Sons, Ltd.
Weidlinger Associates
Authors: Levy Matthys , Hart Gary C.
Published: August 2003

Selected buildings that were designed by the staff of the structural engineering firm Weidlinger Associates are presented for a structural engineering audience. In each case the significant structural engineering challenges are noted so that when the buildings are observed in person one can recognize challenges that were presented and met. Copyright © 2003 John Wiley & Sons, Ltd.
Depletion of SecDF‐YajC causes a decrease in the level of SecG: implication for their functional interaction
Authors: Kato Yoshihisa , Nishiyama Ken-ichi , Tokuda Hajime
Published: August 2003

SecA and an apparatus comprising SecYEG and SecDF‐YajC complexes catalyze protein translocation across the Escherichia coli membrane. SecDF‐YajC and SecG facilitate membrane insertion of SecA, which is the driving force for protein translocation. Here we report that SecDF‐YajC depletion together with SecG depletion nearly completely inhibits protein translocation both in vivo and in vitro, although SecDF‐YajC had been thought to be unnecessary for in vitro translocation. The level of SecG in membranes decreased to about half upon SecDF‐YajC depletion and recovered to a normal level when SecDF‐YajC was expressed. SecDF‐YajC inhibited disulfide bond formation between two SecG molecules possessing a single cysteine residue. These results suggest functional interaction between SecDF‐YajC and SecG.
Ion channels and bacterial infection: the case of β‐barrel pore‐forming protein toxins of Staphylococcus aureus
Authors: Menestrina G , Dalla Serra M , Comai M , Coraiola M , Viero G , Werner S , Colin D.A , Monteil H , Prévost G
Published: August 2003

Staphylococcus aureus strains causing human pathologies produce several toxins, including a pore‐forming protein family formed by the single‐component α‐hemolysin and the bicomponent leukocidins and γ‐hemolysins. The last comprise two protein elements, S and F, that co‐operatively form the active toxin. α‐Hemolysin is always expressed by S. aureus strains, whereas bicomponent leukotoxins are more specifically involved in a few diseases. X‐ray crystallography of the α‐hemolysin pore has shown it is a mushroom‐shaped, hollow heptamer, almost entirely consisting of β‐structure. Monomeric F subunits have a very similar core structure, except for the transmembrane stem domain which has to refold during pore formation. Large deletions in this domain abolished activity, whereas shorter deletions sometimes improved it, possibly by removing some of the interactions stabilizing the folded structure. Even before stem extension is completed, the formation of an oligomeric pre‐pore can trigger Ca2+‐mediated activation of some white cells, initiating an inflammatory response. Within the bicomponent toxins, γ‐hemolysins define three proteins (HlgA, HlgB, HlgC) that can generate two toxins: HlgA+HlgB and HlgC+HlgB. Like α‐hemolysin they form pores in planar bilayers with similar conductance, but opposite selectivity (cation instead of anion) for the presence of negative charges in the ion pathway. γ‐Hemolysin pores seem to be organized as α‐hemolysin, but should contain an even number of each component, alternating in a 1:1 stoichiometry.
Molecular profile of the unique species of traditional Chinese medicine, Chinese seahorse (Hippocampus kuda Bleeker)
Authors: Zhang Ning , Xu Bin , Mou Chunyan , Yang Wenli , Wei Jianwen , Lu Liang , Zhu Junjie , Du Jingchun , Wu Xiaokun , Ye Lanting , Fu Zhiyan , Lu Yang , Lin Jianghai , Sun Zizi , Su Jing , Dong Meiling , Xu Anlong
Published: August 2003

A cDNA library of male Chinese seahorse (Hippocampus kuda Bleeker) was constructed to investigate the molecular profile of seahorse as one of the most famous traditional Chinese medicine materials, and to reveal immunological and physiological mechanisms of seahorse as one of the most primitive vertebrates at molecular level. A total of 3372 expressed sequence tags (ESTs) consisting of 1911 unique genes (345 clusters and 1566 singletons) were examined in the present study. Identification of the genes related to immune system, paternal brooding and physiological regulation provides not only valuable insights into the molecular mechanism of immune system in teleost fish but also plausible explanations for pharmacological activities of Chinese seahorse. Furthermore, the occurrence of high prevalent C‐type lectins suggested that a lectin‐complement pathway might exert a more dominant function in the innate immune system of teleost than mammal. Carbohydrate recognition domain (CRD) without a collagen‐like region in the lectins of seahorse was likely an ancient characteristic of lectins similar to invertebrates.
Munc18‐2/syntaxin3 complexes are spatially separated from syntaxin3‐containing SNARE complexes
Authors: Pombo Isabel , Rivera Juan , Blank Ulrich
Published: August 2003

Exocytosis of mast cell granules requires a vesicular‐ and plasma membrane‐associated fusion machinery. We examined the distribution of SNARE membrane fusion and Munc18 accessory proteins in lipid rafts of RBL mast cells. SNAREs were found either excluded (syntaxin2), equally distributed between raft and non‐raft fractions (syntaxin4, VAMP‐8, VAMP‐2), or selectively enriched in rafts (syntaxin3, SNAP‐23). Syntaxin4‐binding Munc18‐3 was absent, whereas small amounts of the syntaxin3‐interacting partner Munc18‐2 consistently distributed into rafts. Cognate SNARE complexes of syntaxin3 with SNAP‐23 and VAMP‐8 were enriched in rafts, whereas Munc18‐2/syntaxin3 complexes were excluded. This demonstrates a spatial separation between these two types of complexes and suggests that Munc18‐2 acts in a step different from SNARE complex formation and fusion.
Mid-holocene climate change in Lake Bosumtwi, Ghana
Authors: Russell James , Talbot Michael R. , Haskell Brian J.
Published: August 2003

Lake Bosumtwi is one of the most widely studied palaeoclimate archives in West Africa. Results from numerous AMS 14C dates of samples from four piston cores from Lake Bosumtwi show that an abrupt sedimentary transition from a mid-Holocene sapropel to calcareous laminated muds occurred at about 3200 cal yr B.P. High-resolution analyses of the nitrogen isotopic composition of organic matter across this transition confirm its abrupt nature, and suggest that the change may signal a step toward increased aridity and intensified surface winds that affected western equatorial Africa from Ghana to the Congo basin. Northern and Eastern Africa experienced a similar abrupt shift toward aridity during the late Holocene, but at about 5000 cal yr B.P., a difference in timing that illustrates the regional nature of climate changes during the Holocene and the importance of feedback mechanisms in regulating Holocene climate variability. Furthermore, an abrupt change at about 3000 cal yr B.P. occurs at several sites adjacent to the tropical and subtropical Atlantic, which may hint at major changes in the surface temperatures of the tropical Atlantic and/or Pacific at this time.
Paleoecology of late-glacial terrestrial deposits with in situ conifers from the submerged continental shelf of western Canada
Authors: Lacourse Terri , Mathewes Rolf W. , Fedje Daryl W.
Published: August 2003

Extensive portions of the continental shelf off the coast of British Columbia were subaerially exposed during Late Wisconsinan deglaciation due to lowering of relative sea level by as much as 150 m. Paleoecological analyses were conducted at two sites on the emergent continental shelf where terrestrial surfaces with in situ conifers are preserved. The woody plant remains confirm that, during the latest period of subaerial exposure, terrestrial vegetation was established on the continental shelf. Microscopic identification of fossil wood, and analyses of pollen and plant macrofossils from the associated paleosols and overlying shallow pond sediments indicate that productive Pinus contorta-dominated communities with abundant Alnus crispa and ferns grew on the shelf adjacent to and on the Queen Charlotte Islands around 12,200 14C yr B.P. Dwarf shrubs including Salix and Empetrum, and herbaceous plants such as Heracleum lanatum and Hippuris vulgaris, were also important components of the shelf vegetation. Near northern Vancouver Island, mixed coniferous forests dominated by Pinus contorta with Picea, Tsuga spp., Alnus spp., and ferns occupied the shelf at 10,500 14C yr B.P.
New observations on the relative sea level and deglacial history of Greenland from Innaarsuit, Disko Bugt
Authors: Long Antony J. , Roberts David H. , Rasch Morten
Published: August 2003

Relative sea level (RSL) data derived from isolation basins at Innaarsuit, a site on the south shores of the large marine embayment of Disko Bugt, West Greenland, record rapid RSL fall from the marine limit (ca. 108 m) at 10,300–9900 cal yr B.P. to reach the present sea level at 3500 cal yr B.P. Since 2000 cal yr B.P., RSL rose ca. 3 m to the present. When compared with data from elsewhere in Disko Bugt, our results suggest that the embayment was deglaciated later and more quickly than previously thought, at or slightly before 10,300 cal yr B.P. The northern part of Disko Bugt experienced less rebound (ca. 10 m at 6000 cal yr B.P.) compared with areas to the south. Submergence during the late Holocene supports a model of crustal down-warping as a result of renewed ice-sheet growth during the neoglacial. There is little evidence for west to east differences in crustal rebound across the southern shores of Disko Bugt.
Oceanic conditions in the eastern equatorial Pacific during the onset of ENSO in the Holocene
Authors: Loubere Paul , Richaud Mathieu , Liu Zhengyu , Mekik Figen
Published: August 2003

Records from South America show that modern ENSO (El Nino-Southern Oscillation) did not exist 7000 cal yr B.P. and has developed progressively since then. There has been little information available on oceanic conditions in the eastern equatorial Pacific (EEP) to constrain explanations for ENSO onset. We report quantitative observations on thermocline and mixed-layer conditions in the EEP during ENSO start up. We found important changes in both the thermocline and the mixed layer, indicating increased upwelling of cooler waters since 7000 cal yr B.P. This resulted from change in the source and/or properties of waters supplying the Equatorial Undercurrent, which feeds upwelling along the equator and the Peru margin. Modeling shows that ENSO is sensitive to subsurface conditions in the eastern equatorial Pacific and that the changes in the thermocline we observed were driven by extratropical processes, giving these a role in conditioning the development of ENSO. This is in contrast to models that call for control of equatorial Pacific oceanography by tropical processes only. These infer stronger upwelling and cooler surface waters for the EEP during the mid-Holocene, which is not supported by our results.
Isolation and water-level fluctuations of Lake Kachishayoot, Northern Québec, Canada
Authors: Miousse Luc , Bhiry Najat , Lavoie Martin
Published: August 2003

This study combines different methods, including grain size, macrofossil, and pollen analyses, to reconstruct paleogeographical and paleoclimatological conditions for periods before, during, and after the isolation of a small lake (Lake Kachishayoot) in northern Québec. After the retreat of the Laurentide Ice Sheet around 800014C yr B.P., the area was submerged by the Tyrrell Sea. The transition from marine to lacustrine environment occurred about 5400 yr B.P. Two major periods of water-level fluctuations were inferred from organic and mineral sediments: a high water level that occurred after 3200 yr B.P. and a low water level that started before 2200 yr B.P. Our chronological data for the first period are consistent with those from nearby Lac des Pluviers and from other lakes in east central Canada and in the northeastern United States. During the low-water-level period, however, there is no evidence for minor fluctuations, whereas other lakes in northern Québec and east-central Canada underwent several brief lowerings. Long-term changes in atmospheric circulation caused by changing global boundary conditions likely explained long-term water-level fluctuations of Lake Kachishayoot.
Duplexes of 21‐nucleotide RNAs mediate RNA interference in differentiated mouse ES cells
Authors: Zou Gang‐Ming , Wu Wei , Chen Jianjun , Rowley Janet D.
Published: August 2003

RNA interference (RNAi) is a novel phenomenon that can induce post‐transcriptional gene silencing (PTGS) both in animals and plants. RNAi is effective in suppressing specific gene expression in the early mouse embryonic cells and in undifferentiated embryonic stem (ES) cells. In this study, we demonstrate that dsRNA is effective in inducing PTGS in differentiated ES cells: CD34+ embryoid body (EB) cells, as confirmed by western blot and immunocytochemical staining. PU.1 is a key transcription factor in myeloid differentiation. Undifferentiated ES cells do not express PU.1; however it is expressed when ES cells differentiate into EBs. PU.1 could be suppressed by the specific PU.1 dsRNA, but not non‐specific Lamin A/C dsRNA, in the CD34+ EB cells when they were induced to myeloid differentiation in the presence of GM‐CSF and IL‐3. As a consequence, the level of expression of CD115 (M‐CSF receptor), one of the downstream genes regulated by PU.1 is decreased in PU.1 dsRNA treated CD34+ EB cells, but not in Lamin A/C dsRNA treated cells. To explore this phenomenon in other myeloid gene, we also found that C/EBPα gene could be knocked down by C/EBPα dsRNA. Our finding demonstrates that RNAi is effective in inhibiting specific gene expression in differentiated ES cells. RNAi offers a new methodology for study of hematopoietic regulation using ES cell differentiation.
Mesial temporal lobe epilepsy: A pathological replay of developmental mechanisms?
Authors: Cohen Ivan , Navarro Vincent , Le Duigou Caroline , Miles Richard
Published: August 2003

Focal epilepsies of the mesial temporal lobe are often associated with a hippocampal sclerosis. Changes in Cl homeostasis and GABAergic signalling in downstream regions, may contribute to the human pathology. A review of changes in cellular and synaptic function and connectivity after de‐afferentation suggests this epileptic syndrome may involve a pathological replay of developmental mechanisms.
Clinical trials update from the European Society of Cardiology Heart Failure meeting: COMET, COMPANION, Tezosentan and SHAPE
Authors: Coletta Alison P. , Clark Andrew L. , Seymour Anne‐Marie L. , Cleland John G.F.
Published: August 2003

This article continues a series of reports on recent research developments in the field of heart failure. Key presentations made at the European Society of Cardiology Heart Failure Update meeting, held in Strasbourg, France are described. The COMET study showed a 17% relative risk reduction in all‐cause mortality with carvedilol compared with metoprolol tartrate. The COMPANION study, as previously reported, showed encouraging results for the use of cardiac resynchronisation and implantable defibrillator therapy in patients with heart failure, but further evidence is awaited. The results of a study on tezosentan suggest that lower doses of this endothelin antagonist may be clinically more effective with fewer adverse effects compared with higher doses. The SHAPE survey of heart failure awareness in Europe identified a need for further heart failure education amongst the public, patients, their carers and primary care physicians.
Reformed epistemology and Christian apologetics
Authors: SUDDUTH MICHAEL
Published: August 2003

It is a widely held viewpoint in Christian apologetics that in addition to defending Christian theism against objections (negative apologetics), apologists should also present arguments in support of the truth of theism and Christianity (positive apologetics). In contemporary philosophy of religion, the Reformed epistemology movement has often been criticized on the grounds that it falls considerably short of satisfying the positive side of this two-tiered approach to Christian apologetics. Reformed epistemology is said to constitute or entail an inadequate apologetic methodology since it rejects positive apologetics or at least favours negative over positive apologetics. In this paper I argue that this common objection fails on two grounds. First, while the arguments of Reformed epistemology are relevant and useful to apologetics, neither Reformed epistemology nor its epistemological project should be identified with a distinct school or method of apologetics. Secondly, while certain claims of Reformed epistemology seem to imply a rejection of positive apologetics, or at least a preference for negative or positive apologetics, I argue that no such conclusion follows. In fact, although unimpressed by particular versions of natural theology and positive apologetics, Reformed epistemologists have provided criticisms of each that can constructively shape future approaches to the apologetic employment of natural theology and Christian evidences.
Monthly variability in surface pCO2 and net air‐sea CO2 flux in the Arabian Sea
Authors: Sarma V. V. S. S.
Published: August 2003

Recent studies on biogeochemical cycling of carbon in the Arabian Sea, by Joint Global Ocean Flux Study (JGOFS), revealed that the Arabian Sea is a perennial source of carbon dioxide to the atmosphere. The surface pCO2 is governed by physical processes such as water mass transports, upwelling and winter convective mixing, and associated biological processes. Hence surface pCO2 distribution showed significant seasonal and spatial variability. As a result, it is difficult to extrapolate observed data to the entire basin to assess basin‐wide fluxes of CO2 to the atmosphere. On the basis of the data collected during Indian, U.S. JGOFS, and Indian Land‐Ocean Interactions in the Coastal Zone process study programs in the Arabian Sea, multiple regression equations were developed on a seasonal basis to compute dissolved inorganic carbon (DIC) from surface temperature, salinity, and chlorophyll as constraints. Total alkalinity (TA) was computed from surface salinity. On the basis of satellite derived chlorophyll (Coastal Zone Color Scanner) and Levitus surface temperature and salinity climatology, surface TA and DIC were constructed at 1° × 1° grids. Using carbonate dissociation constants, pCO2 levels were computed. The results show the southwest coast of India occupied with very low‐pCO2 waters because of inflow from Bay of Bengal low‐saline water mass during NE monsoon (December–February). On the other hand, this area is occupied with pCO2‐rich (>500 μatm) waters during SW monsoon (June–August) because of coastal upwelling. The highest pCO2 (>700 μatm) were found along the west coast of the Arabian Sea driven by strong upwelling. In the open ocean, higher pCO2 levels were observed in the north (north of 15°N) compared to the southern Arabian Sea round the year, with values higher than those in the atmosphere even in the south. Though no strong physical forcing occurs during spring intermonsoon (March–May), surface pCO2 levels were higher than in the atmosphere. The air‐sea flux of CO2 was found to be high during SW monsoon throughout the Arabian Sea. The west coast of the Arabian Sea releases higher quantities of CO2 to the atmosphere per unit area followed by the northern and eastern Arabian Sea. As a whole, the Arabian Sea (north of 10°N) releases about 90 TgC yr−1 to the atmosphere.
Sr‐Nd‐Pb composition of Mesozoic Pacific oceanic crust (Site 1149 and 801, ODP Leg 185): Implications for alteration of ocean crust and the input into the Izu‐Bonin‐Mariana subduction system
Authors: Hauff Folkmar , Hoernle Kaj , Schmidt Angelika
Published: August 2003

We report Sr, Nd and Pb isotopic compositions of sediments and variably altered igneous rocks from ODP Site 801 (Marianas) and ODP Site 1149 (Izu‐Bonin). These Sites provide the most complete drilled ocean crust sections located in front of the Mariana and Izu‐Bonin trenches and characterize the unmodified isotopic input into these subduction zones. The subducted ocean crust belongs to the oldest (130–167 Ma) in situ Pacific Ocean crust and thus has end‐member character with respect to alteration and sediment load. The lithostratigraphic division of sedimentary units at Site 1149 into clays, cherts, lower clays and carbonates with clay is reflected on isotope correlation diagrams. The Pb isotope data of the sediments show much greater variation than previously reported from this region. Particularly noteworthy are zeolite‐bearing clays and clay bearing carbonates from the lower Units that have Pb isotopic compositions identical to the Izu Volcanic Front. The basaltic basement samples display variable 87Sr/86Sr ratios at near constant 143Nd/144Nd ratios, indicating mixing with seawater derived Sr. Most basaltic samples from Site 1149 and 801 exhibit highly variable 206Pb/204Pb (17.88–20.00) at near constant 207Pb/204Pb and 208Pb/204Pb ratios. Three samples from Site 801 display the most extreme 206Pb/204Pb (23.70–26.86) and 207Pb/204Pb (15.73–15.83) ratios ever measured in altered MORB reflecting an increase of 238U/204Pb ratios (μ), most likely through addition of seawater derived U. Initial Pb isotopes of most samples overlap with the age corrected field of the Pacific MORB source, thus the increase in μ took place shortly after formation of the crust in most samples. According to our new isotope data the radiogenic end‐member of the Izu arc volcanic rocks could either represent Pb from the lower sediment column released from the slab by delayed dewatering or an integrated slab fluid in which 90–95% of the Pb comes from the basaltic crust and 5–10% of the Pb from the sediments. The Pb isotope systematics of the Mariana arc output suggest two component mixing. Both components appear to be input derived with the radiogenic component represented by average Site 801 sediment and the unradiogenic component generated by mixing of ∼80% unaltered crust with ∼20% highly altered crust.
Predicting the mean Bz magnitude, revisited
Authors: Keating C. F. , Jager N. O.
Published: August 2003

Keating et al. [2001] showed that a boxcar average of the Bz magnitude varied in a cyclic pattern with an approximate correlation to the solar sunspot cycle. They then proposed that the McNish‐Lincoln technique, used to forecast sunspot numbers, could also be used to make a forecast of future activity of the mean Bz magnitude. Using this method, they made predictions concerning future mean Bz activity. In this paper, we wish to reexamine these predictions and compare them to actual events. There was a problem with the data in the first paper that we have corrected. We will show that even with this error the observations and premises of the first paper are correct. Applying the McNish‐Lincoln technique to the current data indicates the average magnitude of Bz will decline over the next few years as the current solar cycle goes through its declining phase. These results will aid us in anticipating the average interplanetary magnetic field activity over the near‐term and assist in making appropriate long‐term decisions concerning systems that are vulnerable to solar storms.
Arc‐parallel flow within the mantle wedge: Evidence from the accreted Talkeetna arc, south central Alaska
Authors: Mehl Luc , Hacker Bradley R. , Hirth Greg , Kelemen Peter B.
Published: August 2003

Residual mantle exposures in the accreted Talkeetna arc, Alaska, provide the first rock analog for the arc‐parallel flow that is inferred from seismic anisotropy at several modern arcs. The peridotites exposed at the base of the Jurassic Talkeetna arc have a Moho‐parallel foliation and indicate dislocation creep of olivine at temperatures of ∼1000° to >1100°C. Slip occurred chiefly on the (001)[100] slip system, which has only rarely been observed to be the dominant slip system in olivine. Stretching lineations and olivine [100] slip directions are subparallel to the long axis of the Talkeetna arc for over 200 km, indicating that mantle flow was parallel to the arc axis. The alignment of the olivine [100] axes yields a calculated S wave anisotropy with the fast polarization direction parallel to the arc. Thus (1) the fast polarization directions observed parallel to some modern arcs now have an exposed geological analog; (2) arc‐parallel fast polarization directions can be caused by anisotropic peridotites and do not require the presence of fracture zones, fluid‐filled pockets, or glide on the (010)[001] H2O‐induced slip system; (3) seismic anisotropy beneath modern arcs may be due to slip on (001)[100] with a horizontal foliation rather than slip on (010)[100] with a vertical foliation; and (4) the observed dominance of the (001)[100] slip system may be due to high H2O concentrations, suggesting that strain in the oceanic upper mantle may be accommodated dominantly by (001)[100] olivine slip.
Water mass modification over the continental shelf north of Ronne Ice Shelf, Antarctica
Authors: Nicholls K. W. , Padman L. , Schröder M. , Woodgate R. A. , Jenkins A. , Østerhus S.
Published: August 2003

We use new data from the southern Weddell Sea continental shelf to describe water mass conversion processes in a formation region for cold and dense precursors of Antarctic Bottom Water. The cruises took place in early 1995, 1998, and 1999, and the time series obtained from moored instruments were up to 30 months in length, starting in 1995. We obtained new bathymetric data that greatly improve our definition of the Ronne Depression, which is now shown to be limited to the southwestern continental shelf and so cannot act as a conduit to northward flow from Ronne Ice Front. Large‐scale intrusions of Modified Warm Deep Water (MWDW) onto the continental shelf occur along much of the shelf break, although there is only one location where the MWDW extends as far south as Ronne Ice Front. High‐Salinity Shelf Water (HSSW) produced during the winter months dominates the continental shelf in the west. During summer, Ice Shelf Water (ISW) exits the subice cavity on the eastern side of the Ronne Depression, flows northwest along the ice front, and reenters the cavity at the ice front's western limit. During winter the ISW is not observed in the Ronne Depression north of the ice front. The flow of HSSW into the subice cavity via the Ronne Depression is estimated to be 0.9 ± 0.3 Sv. When combined with inflows along the remainder of Ronne Ice Front (reported elsewhere), sufficient heat is transported beneath the ice shelf to power an average basal melt rate of 0.34 ± 0.1 m yr−1.
Paris emission inventory diagnostics from ESQUIF airborne measurements and a chemistry transport model
Authors: Vautard R. , Martin D. , Beekmann M. , Drobinski P. , Friedrich R. , Jaubertie A. , Kley D. , Lattuati M. , Moral P. , Neininger B. , Theloke J.
Published: August 2003

During the Atmospheric Pollution Over the Paris Area (ESQUIF) experiment a series of airborne measurements were collected in the vicinity of the city of Paris during smog episodes. They are used in combination with an air quality photochemical model in order to diagnose uncertainties in the current emission inventory. Diagnostics are made by comparing simulated with observed concentrations for nitrogen oxides, carbon monoxide, and primary hydrocarbons, taking into account the chemistry and transport processes of these compounds. An emphasis is put on the uncertainty of the results, taking into account the finiteness of the measurement samples, possible errors in the model transport, and chemistry and measurement errors. We examine, in particular, possible sources of bias in the model. For instance, we show that boundary layer depth is underestimated by at most 30% on average. However, sensitivity experiments showed that these model biases, taken individually, cannot alter the qualitative aspects of our results. Only a conspiracy of these biases could possibly shift all our diagnostics toward significantly different results. There is reasonable consistency between simulated and measured concentrations. NOy simulations agree with measured concentrations to within 35%; CO concentrations agree to within a factor of 2. There are significant underestimations and overestimations in some individual primary hydrocarbons. However, the total mass and reactivity of the measured hydrocarbon mixture, which accounts for only about half of the total emitted mass, agree with modeled values to within an estimated uncertainty of 40%. The analysis of results provides clues for improving emission inventories. It is found, for instance, that temperature dependence, which is not considered here, can be a key factor and that hydrocarbon emissions from solvent use may suffer from inaccurate totals or speciation. Another source of uncertainties may be the temporal or spatial distributions of solvent activities.
Linewidths and line intensity measurements in the weak 3A2(000) ← 1A1(000) band of ozone by pulsed cavity ringdown spectroscopy
Authors: Wachsmuth Uwe , Abel Bernd
Published: August 2003

Pulsed cavity ringdown spectroscopy in the near‐infrared spectral range was employed to measure linewidths of the 3A2(000) ← 1A1(000) band of ozone in direct comparison with intracavity laser absorption spectroscopy. It is demonstrated that also for a small ratio, V, which is the ratio of the absorption linewidth and the laser bandwidth, correct linewidths can be determined from a forward modeling of the experimental line profiles, taking explicitly into account the laser bandwidth and the cavity modes. The obtained linewidths have been compared with those measured by intracavity laser absorption spectroscopy and found to agree quantitatively within experimental error. Linewidths as a function of pressure have been analyzed to obtain pressure‐broadening coefficients and the effective linewidth at zero pressure, which is a measure for the excited state lifetimes of the ozone in the excited triplet states. The observed linewidths are a direct observable for the intramolecular dynamics in the low‐lying excited 3A2 triplet state of ozone. In any case, the observed lifetimes for the excited 3A2(000) state in the range between 20 and 130 picoseconds (ps) rule out metastability of this state. Beyond linewidth measurements we have also refined the spectroscopic parameters of this electronically excited state and determined the integrated absorption of the corresponding 3A2(000) ← 1A1(000) transition.
Asian aerosol transport to Alaska during ACE‐Asia
Authors: Cahill Catherine F.
Published: August 2003

Aerosols were collected at Adak Island, Alaska, one of the southernmost Aleutian Islands, and the Poker Flat Research Range, 30 km northeast of Fairbanks, Alaska, during the 2001 Aerosol Characterization Experiment‐Asia Intensive Field Phase (March through April 2001). The size‐ and time‐resolved aerosols were collected using three‐stage DRUM aerosol sampling systems and analyzed for 42 elements between sodium and lead using synchrotron X‐ray fluorescence. The results of these elemental analyses and back trajectory calculations clearly demonstrate the transport of Asian aerosols into Alaska and the sub‐Arctic. In addition, the aerosols at Adak Island demonstrate that northern Europe and Russia are contributing to the aerosol composition, loading, and deposition over the North Pacific Ocean. The peak concentration of large (1.15 to 2.5 μm in aerodynamic diameter) soil aerosols at Poker Flat is 15% of that observed at Adak Island. If it is assumed that the same air mass is sampled at both sites and that deposition is the only aerosol removal mechanism, then this implies a large deposition of crustal elements to the marine and terrestrial ecosystems along the transport path. However, the observed concentration difference could be influenced by differences in transport path, the layered nature of Asian aerosol transport, and different vertical mixing properties over Adak Island and Poker Flat. Future work will examine the relative impacts of the above processes on the observed soil element concentrations.
Simulation of atmospheric nucleation mode: A comparison of nucleation models and size distribution representations
Authors: Korhonen H. , Lehtinen K. E. J. , Pirjola L. , Napari I. , Vehkamäki H. , Noppel M. , Kulmala M.
Published: August 2003

Atmospheric particle formation and growth were investigated using different nucleation models and size distribution representations. Nucleation was modeled using recently developed parameterizations for binary nucleation of water and sulphuric acid and ternary nucleation of water, sulphuric acid, and ammonia. A comparison with older nucleation parameterizations, combined with full aerosol dynamics, demonstrated that the difference in nucleation rate (1–2 orders of magnitude) is clearly reflected in the resulting total particle concentration. A comparison of binary and ternary nucleation schemes showed that above 240 K the ternary nucleation rate exceeds the binary by over 10 orders of magnitude, indicating that in most cases, at lower tropospheric conditions, only ternary nucleation can be relevant. In addition, the performance of aerosol dynamics models applying either a multimodal monodisperse or a fixed sectional size distribution representation was evaluated against a molecular resolution model, which follows the changes in the nucleation mode particle size distribution molecule by molecule. Regarding total number concentration, the sectional method converged to the molecular resolution approach when increasing the number of size sections. With strong condensational growth, however, numerical diffusion problems were evident. Overall, the performance of the sectional method with low number of sections was not satisfactory. The monodisperse method gave very good results, at least in terms of total number, when the background modes were set to match the condensation sinks of respective lognormal modes. On the basis of our study the multimodal monodisperse method seems to be a possible candidate when selecting the size distribution approach for large‐scale atmospheric models.
F2 region maximum electron density height predictions for South American latitudes
Authors: Ezquer R. G. , Scidá L. , Mansilla G. A. , Mosert M. , Herrera M. F.
Published: August 2003

Values of the F2 region maximum electron density height (hmF2) calculated using ground ionosonde data at South American latitudes are used to check the validity of the International Reference Ionosphere (IRI) to predict this variable. With this in mind we compare hmF2 predictions given by the model when measurements of critical frequency of F2 region and propagation parameter M(3000)F2 were used as input parameter in IRI (hmF2IRI‐Exp), against those obtained using the standard International Radio Consultative Committee (CCIR) option (hmF2IRI‐CCIR). In this paper we used hmF2IRI‐Exp values because hmF2 measurements were not available for the considered cases. Moreover, a comparison of the measured M(3000)F2 values with the CCIR predictions have been done. The results show that, in general, the standard predictions follow the diurnal tendency observed in the hmF2IRI‐Exp values. At low latitudes the hmF2IRI‐Exp values show oscillations not reproduced by the standard option. Cases with disagreements for 24 hours have been observed at high latitudes. Other cases with good agreement have been also obtained. The results suggest that, in general, the standard option of the model gives good hmF2 predictions at South American latitudes. Few cases showed deviation between 15 and 25%. As we expected, the obtained results suggest that the deviation between predicted and measured M(3000)F2 values is the main contribution for the deviation between hmF2IRI‐CCIR and hmF2IRI‐Exp. The comparison with the results obtained in previous work shows that the IRI performance in predicting M(3000)F2 and hmF2 is better than in predicting foF2.