bluuebunny/crossref_metadata_2025 huggingface dataset:
Continuous and discontinuous phase transitions in hypergraph processes
Authors: Darling R. W. R. , Levin David A. , Norris James R.
Published: April 2004

Let V denote a set of N vertices. To construct a hypergraph process, create a new hyperedge at each event time of a Poisson process; the cardinality K of this hyperedge is random, with generating function ρ(x) =def∑ ρkxk, where P(K = k) = ρk; given K = k, the k vertices appearing in the new hyperedge are selected uniformly at random from V. Assume ρ1 + ρ2 > 0. Hyperedges of cardinality 1 are called patches, and serve as a way of selecting root vertices. Identifiable vertices are those which are reachable from these root vertices, in a strong sense which generalizes the notion of graph component. Hyperedges are called identifiable if all of their vertices are identifiable. We use “fluid limit” scaling: Hyperedges arrive at rate N, and we study structures of size O(1) and O(N). After division by N, numbers of identifiable vertices and hyperedges exhibit phase transitions, which may be continuous or discontinuous depending on the shape of the structure function − log(1 − x)/ρ′(x), x ∈ (0, 1). Both the case ρ1 > 0, and the case ρ1 = 0 < ρ2 are considered; for the latter, a single extraneous patch is added to mark the root vertex. Published 2004 Wiley Periodicals, Inc. Random Struct. Alg., 2004
Comparison between some common influence coefficient algorithms
Authors: Willis J. P. , Lachance G. R.
Published: April 2004

The quality of the results obtainable from a number of different algorithms available in modern manufacturers' software has been compared using data for a single sample of Ni–Fe–Cr, for considerations of space. The conclusions reached are based on similar comparisons using many samples of different compositions. The aim was to demonstrate that, when all criteria (variable theoretical influence coefficients; total concentration of all elements equals 100%; homogeneous, flat and infinitely thick samples) relating to emission theory are met, a number of valid mathematical expressions are available to the user. The mathematical expressions (algorithms) examined are Lucas‐Tooth and Price, Rasberry–Heinrich and Lachance–Traill, all using empirical influence coefficients; Claisse–Quintin and COLA using linear and hyperbolic variable theoretical influence coefficients, respectively; and Broll–Tertian, Rousseau, Lachance–Claisse and de Jongh, using variable theoretical influence coefficients based on fundamental parameters. The last four algorithms give exactly the same results, despite the fact that the ‘structures’ of the algorithms are all very different and that the magnitudes of the influence coefficients are also very different (except that the magnitudes and signs of influence coefficients are the same for the Broll–Tertian and Rousseau algorithms). If any of the four algorithms is used correctly, each will give acceptable results. Copyright © 2004 John Wiley & Sons, Ltd.
A new approach to correcting theoretical emitted intensities for absorption and enhancement effects
Authors: Willis J. P. , Lachance G. R.
Published: April 2004

This paper introduces the possibility of replacing the usual additive corrections for absorption and enhancement by multiplicative factors. The possibility of deriving simple multiplicative factors to correct for inter‐element matrix effects, namely $a_{s}'$ and $a_{s}''$, to correct for absorption of primary and secondary radiation, respectively, and enhancement ($e_{\rm s}^{*}$), is demonstrated. The use of the new coefficients, $a_{s}'$, $a_{s}''$ and $e_{\rm s}^{*}$, derived directly from mass attenuation coefficients, simplifies the understanding of, and allows the stepwise evaluation of, the excitation of theoretical emitted intensities in XRF spectrometry. The approach is especially useful in providing a more consistent definition of theoretical intensity emitted from an infinitely thick sample, as compared with the classical formalism involving the use of mass attenuation coefficients. The approach has proved particularly useful in the classroom. Copyright © 2004 John Wiley & Sons, Ltd.
Benthic littoral Polychaeta “Sedentaria” of Terra Nova Bay (Ross Sea, Antarctica)
Authors: Cantone G. , Di Pietro N.
Published: April 2004

The Polychaeta “Sedentaria” collected in Terra Nova Bay (Ross Sea) during the Second Italian Oceanographic Antarctic Expedition (1989–90) have been studied. A total of 1518 specimens have been examined and 43 species, belonging to 14 families, have been identified. A new species of Oweniidae, Myriochele antarctica and a new subspecies of Spionidae, Scolelepis eltaninae nudipalpa are described. Terebellidae was the most important family in number of species, Spionidae, Oweniidae and Orbiniidae in number of individuals. More than 60% of the species are endemic to Antarctic and sub-Antarctic areas.
Killing Kyoto
Authors: Walton David
Published: April 2004

Ignorance has never been an excuse in law, but politics clearly plays by different rules. By pretending that global warming simply isn't happening, President George W. Bush is clearly setting new standards for ostriches. Politicians all want to feature in the history books but Bush's ploy to be defender of the American people at all costs is positively breath-taking. Having provided lukewarm support for the Kyoto agreement before the election, to ensure he was not over-trumped by Al Gore, he has now apparently had a change of heart. It is hard to decide if this constitutes outright lying or simple everyday deceit. Apparently the 4000 scientists involved in the recent report by the Intergovernmental Panel on Climate Change and all those other countries that signed up to the Kyoto agreement must be wrong because the Bush advisors from the energy industry say that they are wrong. What world are these people living in?
A new species of Ammothea (Pycnogonida) and other pycnogonids from Livingston Island and surrounding waters (South Shetland Islands, Antarctica)
Authors: León Tomás Munilla
Published: April 2004

Fifty-nine species of pycnogonids belonging to sixteen genera and eight families were collected during a cruise near Livingston Island and surrounding waters, from depths between 0 and 1019 m. The new species Ammothea bentartica is described fully, illustrated and compared with similar species. The family Nymphonidae had both the greatest number of species (20) and number of specimens (67% of 1201). The most abundant species were Nymphon charcoti and N. australe. Nymphon paucidens and Pallenopsis buphtalmus were collected for a second time. The collections increased the geographical distribution of five species and the depth range of seven species. This collection appears typical of the West Antarctic zone.
The occurrence of the copepods Stephos longipes (Calanoida) and Drescheriella glacialis (Harpacticoida) in summer sea ice in the Weddell Sea, Antarctica
Authors: Schnack-Schiel Sigrid B. , Thomas David N. , Haas Christian , Dieckmann Gerhard S. , Alheit Ruth
Published: April 2004

In January to March 1997, a RV Polarstern cruise that transected the Weddell Sea resulted in samples being taken in thick pack ice in the south-eastern Weddell Sea and then along the marginal ice edge towards the Antarctic Peninsula. Several ice types were thus sampled over a wide geographic area during late summer/early autumn. Common features of the first warm period was the occurrence of surface ponds, and that many floes had quasi-continuous horizontal gaps, underlying a layer of ice and metamorphic snow. With the onset of cold air temperatures in late February the gaps rapidly refroze. The calanoid copepod Stephos longipes occurred in all habitats encountered and showed highest numbers in the surface ice in summer, in the gap water during both seasons and in the refrozen gap water in autumn. Nauplii outnumbered copepodids in the surface ice and refrozen gap water, while in the gap water copepodids, mainly stages CI–CIII in summer and CII–CIV in autumn, comprised about 70% of the total population. The harpacticoid species Drescheriella glacialis did not occur in all habitats and was missing in surface ponds and new ice. Nauplii of D. glacialis were rarely found in gap water, but predominated in the refrozen gaps.
Publishing and the Scientific Community
Authors: Walton David W. H.
Published: April 2004

Publishing is changing rapidly, as is the management of much of the scientific community world wide. Unfortunately there are features of both that should give considerable cause for alarm if one cares to look forward a few years. Let's begin with the remarkable consolidation of wonership in scientific publishing culminating in the latest move - the acquisition of Harcourt by Reed Elsevier- which has been investigated by the Competition Commission in the UK as being potentially against the public interest. Those who buy Reed Elsevier journals at present will know that their subscription rates are some of the highest in the world. It is not obvious that scientists will see any benefit from this takeover. Indeed, what will happen to the provision of information to working scientists as library budgets decline everywhere? Is increasingly expensive equipment for experimental use really more important than the literature? Governments will say that the Web will meet scientists needs to which my reply is that much of its content is uncontrolled rubbish and it certainly does not replace the quality controlled material available in the journals. So our first conclusion for the future could be that consolidation of ownership of journals is bad for science and unless, there is a significant change in library funding, many commercial journals are likely to price themselves out of the general market, leaving only those published by learned societies or charities at an affordable level. Bad news.
Limnology and biology of saline lakes in the Rauer Islands, eastern Antarctica
Authors: Hodgson D. A. , Vyverman W. , Sabbe K.
Published: April 2004

The Rauer Islands contain more than fifty shallow lakes and small ephemeral ponds. Despite their proximity to the Vestfold Hills - one of the most diverse and intensively studied lake districts of eastern Antarctica - the lakes of the Rauer Islands have remained undescribed. In this study the physical and chemical limnology and biology of ten lakes is presented and their species-environment relationships explored using multivariate statistics. Analyses of chemical and biological data indicate that the Rauer Islands form a distinct limnological province amongst the lakes of the Prydz Bay oases. Salinities range from hypo- to hyper-saline with an ionic order close to that of seawater. Deviance from this order indicates either an earlier origin for some of the most hypersaline lakes when compared with the Vestfold Hills, more rapid evaporation vs precipitation or differences in the sources of ions resulting from isostatic history. With fluctuating salinities, winter water temperatures below –10°C, seasonal ice and slush formation, desiccation and high levels of solar radiation, the lacustrine environment presents considerable abiotic challenges for biological survival. Results indicate that there is little or no planktonic flora in the lakes and no zooplankton were encountered. Despite this, analyses of pigments, diatoms and other micro-algae revealed an active and diverse benthic biota characterized by filamentous cyanobacteria with interstitial algae. Thirty-eight diatom taxa, and a selection of Chlorophyta and Xanthophyta were detected amongst the cyanobacteria. Clusters in the diatom data correspond to salinity. Further analyses of the relationships between the biota and their environment revealed some of the strategies employed for survival. In particular, the synthesis of scytonemin was detected. This pigment is known to function as an extracellular UV sunscreen which protects cyanobacterial cells against damage by ultraviolet radiation. These results support the hypothesis that environmental extremes and biogeographical isolation control the biology of these lakes.
Variation in breeding success in Wilson's storm petrels: influence of environmental factors
Authors: Quillfeldt Petra
Published: April 2004

The climatic and sea ice conditions of the Southern Ocean are highly variable within and between years, and a better understanding of the influence of climatic conditions on the various parts of the marine food chain is needed. This paper summarizes data on breeding success of a krill-dependent predator, the Wilson's storm petrel Oceanites oceanicus, in a colony on King George Island, South Shetland Islands, Antarctica, over four breeding seasons from 1995/1996 to 1999/2000. The seasons differed greatly in environmental conditions and in the resulting food availability which was reflected in inter- and intra-annual variations in feeding frequency. The breeding success was consequently variable. Starvation, the main cause of chick mortality in three out of four breeding seasons was associated with reduced sea ice cover in winter, which is known to depress food availability in the following breeding season. Food delivery rates also depended on the prevailing winds, which drive the transport of zooplankton-rich water masses. Snowstorms caused additional chick mortality in two out of four seasons when nest burrows became blocked. Implications for the use of Wilson's storm petrels for monitoring of krill are considered.
Winter distribution and abundance of crabeater seals off George V Land, East Antarctica
Authors: McMahon Clive , Hindell Mark , Dorr Tony , Massom Robert A.
Published: April 2004

This study is the first to describe the winter distribution of crabeater seals (Lobodon carcinophagus) in East Antarctica. The study was conducted in the Mertz Glacier Polynya region from July to August 1999. In total 89 crabeater seals were seen in 26 groups which ranged in size from 1 to 35 animals (mean = 3.2). The mean observed haulout density along a 200 m wide strip transect was 0.108 seals per km2, or 0.042 groups per km2. Crabeater seals were not uniformly distributed in the polynya but selected areas of stable ice over shallow (< 1000 m) waters. We used a generalized linear model to assess the relationship of seal distribution to the physical attributes of sea ice concentration, thickness, and ocean depth. We found that ice thickness and ocean depth were the most important determinants of seal distribution. Crabeater seals occurred in areas where the ice affords them a stable haulout platform while allowing them access to Antarctic krill that live directly beneath the ice.
Crystal and Molecular Structure and Biological Activity of Z)-(Benzoyloxymethyl-NNO-azoxy)methane
Authors: Tate Max E. , Delaere Ian M. , Jones Graham P. , Seawright Alan A. , Tiekink Edward R. T.
Published: April 2004

Characterization of
(benzoyloxymethyl-NNO-azoxy)methane,
from benzoylation of the cycasin aglycone methylazoxymethanol, commonly
referred to as MAM, is reported. Crystal structure analysis shows that the
azoxy substituents have the Z configuration. Crystals
are monoclinic, space group
P21/c,
a 7·436(2), b
8·771(2), c 14·640(1) Å, β
90·73(1)°, Z 4; the structure was refined to
final R 0·048 by using 1171 reflections with
I ≥ 3·0σ(I ). Subcutaneous injection of
(Z)-(benzoyloxymethyl-NNO-azoxy)methane
in mice showed liver changes typical of the corresponding MAM acetate-induced
hepatotoxicity. This permits correlation of hepatotoxic effects with the
Z configuration of the aglycone. Histological
examination of the brain and spinal cord revealed no significant changes at a
dosage of 52· 6 mg/kg.
Assessment of Double-Barrelled Heck Cyclizations as a Means for Construction of the 14-Phenyl-8,9-dihydro- 6H-[1]benzopyrano[4′,3′:4,5]pyrrolo[2,1-a]isoquinolin- 6-one Core Associated with Certain Members of the Lamellarin Class of Marine Natural Product
Authors: Banwell Martin G. , Hockless David C. R. , Flynn Bernard L. , Longmore Robert W. , Rae David
Published: April 2004

The 1,2,4-trisubstituted pyrrole (4), which is readily prepared from pyrrole
itself, undergoes double- barrelled Heck cyclizations to give,
inter alia, compounds (3) and (17) for which crystal
structures have been determined. Product (3) constitutes the core associated
with several key members, e.g. (1) and (2), of the lamellarin class of marine
alkaloid.
The Preparation of a Mixed-Ligand Cobalt(III) Complex of DPPZ and Ethylenediamine: Crystal Structures of [Co(en)2(DPPZ)] (ClO4)3.0·5H2O, [Co(en)2(bpy)]Br(ClO4)2 and [Co(en)2(phen)] Br3
Authors: Funston Alison M. , Gable Robert W. , McFadyen W. David , Tregloan Peter A.
Published: April 2004

The complex [Co(en)2(DPPZ)]
(ClO4)3 (3) has been synthesized,
and the crystal structures of this complex and those of
[Co(en)2(bpy)]
Br(ClO4)2 (1) and
[Co(en)2(phen)] Br3 (2)
have been determined. Crystal data for (1): M 614 .
13, monoclinic, space group
C2/c (No. 15),
a 16 . 7834(16), b 16 .
308(3), c 8 . 3167(15) Å,
β 104 . 932(11)°, V
2199 . 4(6) Å, F(000) 1240,
Z 4, Dc 1 . 855 g
cm−3, µ 2 . 895
cm−1 , Mo Kα (graphite monochromatized)
radiation, γ 0 . 71073 Å, T 293(1) K.
Crystal data for (2): M 599 . 07, triclinic, space
group P1 (No. 2), a 7 .
7113(11), b 10 . 633(2), c 12
. 9884(18) Å, α 85 . 745(15), b 78
. 258(11), γ 74 . 967(16)°, V 1006
. 7(3) Å, F(000) 588, Z
2, Dc 1 . 976 g
cm−3, µ6 . 819
cm−1 , MoKα (graphite monochromatized)
radiation, γ 0 . 71073 Å, T 293(1) K.
Crystal data for (3): M 773 . 44, monoclinic, space
group P
21/c (No. 14),
a 20 . 296(2), b 9 .
6197(11), c 15 . 725(2) Å,
β 92 . 850(10)°, V
3066 . 4(6) Å, F(000) 1579,
Z 4, Dc 1
. 675 g cm−3 , µ
0 . 898 cm−1 , MoKα(graphite
monochromatized) radiation, γ 0 . 71073 Å,
T 293(1) K. In all three complexes the cobalt is in the
usual octahedral environment, with the cations being linked by hydrogen bonds
between the amine hydrogens and the anions into extended
structures.
Negative selection of semimature CD4
+
8
-
HSA
+
thymocytes requires the BH3-only protein Bim but is independent of death receptor signaling
Authors: Villunger Andreas , Marsden Vanessa S. , Zhan Yifan , Erlacher Miriam , Lew Andrew M. , Bouillet Philippe , Berzins Stuart , Godfrey Dale I. , Heath William R. , Strasser Andreas
Published: April 2004

T cell receptor/CD3 ligation induces apoptosis in semimature CD4
+
8
-
HSA
+
thymocytes, and this helps establish immunological tolerance and constitutes one of the safeguards against autoimmune disease. We analyzed several knockout and transgenic mouse lines and found that T cell receptor/CD3-ligation-induced killing of semimature thymocytes occurred independently of Fas and “death receptor” signaling in general but required the proapoptotic BH3-only protein Bim and could be inhibited by Bcl-2. Loss of Apaf-1 or caspase-9, which act downstream of the Bcl-2 family protein family, provided only minor protection, indicating that the “apoptosome” functions as an amplifier rather than as an essential initiator of this death program. These results reveal the mechanisms of apoptosis in negative selection of semimature thymocytes and have implications for immunological tolerance and autoimmunity.
Sensory neuron-specific receptor activation elicits central and peripheral nociceptive effects in rats
Authors: Grazzini Eric , Puma Carole , Roy Marie-Odile , Yu Xiao Hong , O'Donnell Dajan , Schmidt Ralf , Dautrey Sophie , Ducharme Julie , Perkins Martin , Panetta Rosemarie , Laird Jennifer M. A. , Ahmad Sultan , Lembo Paola M. C.
Published: April 2004

The sensory neuron-specific G protein coupled receptors (SNSRs) have been described as a family of receptors whose expression in small diameter sensory neurons in the trigeminal and dorsal root ganglia suggests an implication in nociception. To date, the physiological function(s) of SNSRs remain unknown. Hence, the aim of the present study was to determine the effects of rat SNSR1 activation on nociception in rats. The pharmacological characterization of rat SNSR1 was initially performed
in vitro
to identify a specific ligand, which could be used subsequently in the rat for physiological testing. Among all ligands tested, γ2-MSH was the most potent at activating rat SNSR1. Structure–activity relationship studies revealed that the active moiety recognized by rat SNSR1 was the C-terminal part of γ2-MSH. The radiolabeled C-terminal part of γ2-MSH, γ2-MSH-6–12, bound with high affinity to membranes derived from rat skin and spinal cord, demonstrating the presence of receptor protein at both the proximal and distal terminals of dorsal root ganglia. To investigate the physiological role of SNSR, specific ligands to rat SNSR1 were tested in behavioral assays of pain sensitivity in rats. Selective rat SNSR1 agonists produced spontaneous pain behavior, enhanced heat and mechanical sensitivity when injected intradermally, and heat hypersensitivity when injected centrally, consistent with the localization of rat SNSR1 protein at central and peripheral sites. Together, these results clearly indicate that the SNSR1 plays a role in nociception and may provide novel therapeutic opportunities for analgesia.
Survival of largemouth bass, bluegill and channel catfish embryos after electroshocking
Authors: Henry T. B. , Grizzle J. M.
Published: April 2004

Survival to hatching was determined after electroshocking embryos of largemouth bass Micropterus salmoides, bluegill Lepomis macrochirus and channel catfish Ictalurus punctatus. Embryos at different developmental stages were exposed for 20 s to homogeneous electric fields (4–16 V cm−1) of direct current (DC) or 60 or 120 Hz pulsed direct current (PDC) in water of 100 μS cm−1 ambient conductivity. For all species, DC reduced survival of embryos at developmental stages before, during, or soon after epiboly; but survival did not differ from controls during later developmental stages. Survival of largemouth bass and bluegill was not reduced by 60 or 120 Hz PDC except for bluegill exposed at 12 h post‐fertilization. Channel catfish embryo survival was <5% when exposed to 60 or 120 Hz PDC at 8 h post‐fertilization, survival improved for embryos exposed at 67 h to 60 Hz but not to 120 Hz, and all embryos survived exposure to PDC at 150 h post‐fertilization. Exposure durations as short as 5 s resulted in <10% survival of largemouth bass during sensitive stages. All bluegill embryos aged 22 h post‐fertilization hatched prematurely after exposure to 16 V cm−1 DC, but survival was not affected. The use of PDC for electroshocking near largemouth bass and bluegill nests could reduce the negative effects on survival of these species; however, PDC can reduce survival of channel catfish embryos.
Validation of the periodicity of increment formation in the otoliths of a cichlid fish from Lake Tanganyika, East Africa
Authors: Egger B. , Meekan M. , Salzburger W. , Mwape L. , Makasa L. , Shapola R. , Sturmbauer C.
Published: April 2004

Tetracycline was used as a chemical tag in a mark‐recapture study to examine the pattern of increment formation in the otoliths ofTropheus moorii, a rock‐dwelling cichlid from Lake Tanganyika. A total of 256 fish were captured by divers and injected with tetracycline. Of these, nine were recaptured after either 1 or 2 years at liberty and eight retained tags within their otoliths. Comparison of the number of growth increments formed after the tag and the time at liberty demonstrated that increments were deposited on an annual basis in the otoliths of this species. Furthermore, there was a strong relationship between otolith mass and age suggesting that otoliths grew at a predictable rate throughout the life of the fish. Validation of an annual pattern of increment deposition allowed age and growth information to be derived from otoliths. This showed thatT. mooriigrew rapidly to attain adult size by 3 years of age. Males grew faster than females and also attained a larger size than females (8·74v. 7·91 cmLSrespectively). The longevity of some of these small freshwater fish was surprising; the oldest individual had an age of 10 years, while the average age of adults was 4 years.
Effects of central administration of arginine vasotocin on monoaminergic neurotransmitters and energy metabolism of rainbow trout brain
Authors: Sangiao‐Alvarellos S. , Lapido M. , Miguez J. M. , Soengas J. L.
Published: April 2004

In a first set of experiments, intracerebroventricular (ICV) treatment of 1 μl 100 g−1 body mass of Cortland saline containing different doses (1–20 nmol μl−1) of arginine vasotocin (AVT) produced after 180 min dose‐dependent changes in levels of brain neurotransmitters in several brain regions and pituitary of rainbow trout Oncorhynchus mykiss. Thus, an enhancement of serotonergic and dopaminergic activity, together with a decreased noradrenergic activity, were observed both in the hypothalamus and pituitary of AVT‐treated fish. In the other brain regions assessed, only increased serotonergic activity in the optic lobes, and decreased dopaminergic activity in the telencephalon of AVT‐treated fish were noticed. Changes observed in monoamine levels resemble those observed during osmotic adaptation of euryhaline fishes. In a second set of experiments, fish were ICV injected with AVT as described above to assess changes in several variables of brain energy metabolism. The results obtained show a dose‐dependent enhancement of brain glycogenolytic potential in the brain of AVT‐treated fish, that again resemble the changes observed in euryhaline fishes during osmotic acclimation.
Implementation of concurrent red blood cell and platelet collection by apheresis in a university haemapheresis unit
Authors: Moog R.
Published: April 2004

summary The present study analyses the number of concurrently collected red blood cell (RBC) units in plateletpheresis donors and the reasons why donors were deferred from multicomponent collection. Donors undergoing concurrent collection of RBCs and platelets (PLTs) were retrospectively evaluated for haemoglobin values and the reasons for deferral over a period of 1 year. A total of 404 RBC units were concurrently collected with PLTs. An average of 1·8 RBC units per year was collected from each donor. The baseline haemoglobin values were almost equal for the RBC donations. An RBC unit was not collected in 190 aphereses. Most frequent reasons for the noncollection of an RBC product were a donation interval of less than 3 months (20·5%), haematoma and blood flow problems (18·9%) and low pre‐haemoglobin values (17·4%). Donor eligibility has to be taken into account to optimize concurrent RBC collection in plateletpheresis.
A novel blood group B subgroup: serological and genetic studies
Authors: Estalote A. C. , Palatnik M. , Chester M. A. , Olsson M. L. , Sant'Anna Gomes B. M.
Published: April 2004

summary A discrepancy in the ABO blood groups between a newborn child and her parents was identified. Serological and DNA investigative techniques were performed. A weak variant of B (Bw) was detected on the erythrocytes of the child, her grandmother and great‐uncle. Adsorption–elution studies showed that their erythrocytes adsorb and yield anti‐B on elution. The Bw antigenic strength of the A1Bw cells of her mother and maternal aunt was reduced when compared to that of the A2Bw from another family member. Only one of 15 different anti‐B sera agglutinated the A1Bw erythrocytes. Agglutinin anti‐B that reacted strongly with normal B erythrocytes and did not agglutinate the Bw cells, was found in the sera of the A1Bw individuals. The Bw serum glycosyltransferase could not convert O cells into B cells and no B substance was found in saliva. All family members with the Bw/ABw phenotypes were heterozygous for a B allele and DNA sequencing revealed a novel missense mutation in exon 7 of the B allele (556A > G), resulting in M186V. This substitution changes a highly conserved region of the enzyme, proposed to be a disordered loop near the enzyme cleft, and is expected to diminish the enzyme's activity, leading to this Bw phenotype.
Pharmacokinetics and safety of recombinant anti‐RhD in healthy RhD‐negative male volunteers
Authors: Bichler J. , Spycher M. O. , Amstutz H.‐P. , Andresen I. , Gaede K. , Miescher S.
Published: April 2004

summary In this first‐in‐man study, we assessed the pharmacokinetics, safety and tolerability of MonoRho, a human recombinant monoclonal anti‐RhD immunoglobulin G1 (IgG1) antibody. Eighteen RhD‐negative healthy male volunteers were randomized in two groups to receive a single administration of 300 µg of MonoRho either intravenously or intramuscularly. There were no symptoms of allergic or anaphylactic type reaction in any subject, and there was no evidence of any MonoRho‐related changes in laboratory safety parameters. None of the subjects mounted a detectable immune response to MonoRho. Serum samples were obtained up to 91 days after injection to measure anti‐D IgG concentrations by flow cytometry. After intramuscular administration of MonoRho, anti‐D IgG concentrations gradually increased reaching peak levels after a mean of 3·4 days. After 3 weeks, the mean anti‐D IgG concentrations after intravenous and intramuscular administration became virtually equal to each other and remained so thereafter. In both the treatment groups, the mean elimination half‐life was about 18 days and thus similar to that described for plasma‐derived anti‐D IgG. The bioavailability of MonoRho after intramuscular administration was estimated as 46%. The excellent tolerability and safety of MonoRho as well as its expected elimination half‐life supports the continued clinical development of this compound.
Attachment to a National Money: Evidence on Currency Holding at Different Levels of Development
Authors: Jefferson Philip N. , O'Connell Stephen A.
Published: April 2004

Most governments issue and maintain a national money stock. Their reasons for doing so include national identity, deficit finance, and policy independence. Against this background, the authors examine agents’ attachment to national currencies as revealed in the pattern of currency holding across countries and over time. The econometric evidence suggests that economic theory can enhance our understanding of these patterns. In a sample of more than 130 countries from 1960 to 1998, the most defensible reduced‐form estimates impute some explanatory power to the various stages of financial development. Along with expected inflation and worldwide financial innovation, this factor provides a partial explanation of currency use around the world. Much variation in currency use across countries over time remains unexplained, however. This suggests that economists’ understanding of the attachment to national currencies is far from complete.
Swidden Agriculture in Developing Countries
Authors: Batabyal Amitrajeet A. , Beladi Hamid
Published: April 2004

Small farmers in many tropical developing countries practice swidden agriculture. A key aspect of swidden agriculture is the time period during which the land is left fallow. This paper uses a new ecological–economic approach to study the fallow period and to determine the optimal length of this period in swidden agriculture. The authors first construct a theoretical model of a parcel of forest land that has been cleared for swidden agriculture. It is then shown how the dynamic and the stochastic properties of this cleared land can be used to derive two objective functions for a small farmer that are ecologically meaningful. Finally, using these two objectives, a probabilistic approach to the determination of the optimal length of the fallow period is discussed. In this approach, the focus of the small farmer is on maintaining the ecological and the economic sustainability of swidden agriculture on the cleared parcel of forest land (CPFL).
Reforming Food Subsidy Schemes: Estimating the Gains from Self‐targeting in India
Authors: Dutta Bhaskar , Ramaswami Bharat
Published: April 2004

The paper uses the theoretical framework of the theory of tax reform to analyze whether a “small” change in an existing food subsidy program can be both welfare‐improving and revenue‐neutral. It shows how existing econometric methods can be adapted to estimate demand parameters even when household‐level data exhibit little price variation because the government controls food prices. The methodology is used to estimate welfare changes from shifting a rupee of subsidy on existing commodities to coarse cereals in the Indian public distribution system.
Influence of a threonine residue in the S2 ligand binding domain in determining agonist potency and deactivation rate of recombinant NR1a/NR2D NMDA receptors
Authors: Chen Philip E. , Johnston Alexander R. , Mok M. H. Selina , Schoepfer Ralf , Wyllie David J. A.
Published: April 2004

NR1/NR2D NMDA receptors display unusually slow deactivation kinetics which may be critical for their role as extrasynaptic receptors. A threonine to alanine point mutation has been inserted at amino acid position 692 of the NR2D subunit (T692A). Recombinant NR1a/NR2D(T692A) NMDA receptors have been expressed in Xenopus laevis oocytes and their pharmacological and single‐channel properties examined using two‐electrode voltage‐clamp and patch‐clamp recording techniques. Glutamate dose–response curves from NR1a/NR2D(T692A) receptor channels produced an approximately 1600‐fold reduction in glutamate potency compared to wild‐type NR1a/NR2D receptors. There was no change in Hill slopes or gross reduction in mean maximal currents recorded in oocytes expressing either wild‐type or mutant receptors. The mutation did not affect the potency of the co‐agonist glycine. The shifts in potency produced by NR2D(T692A) containing receptors when activated by other glutamate‐site agonists such as aspartate or NMDA were 30‐ to 60‐fold compared to wild‐type. Single‐channel conductance levels of NR1a/NR2D(T692A) mutant receptors were indistinguishable from wild‐type NR2D‐containing channels. Additionally NR1a/NR2D(T692A) receptors showed the transitional asymmetry that is characteristic of NR2D‐containing NMDA receptors. Rapid applications of glutamate on outside‐out patches containing NR1a/NR2D(T692A) receptors produced macroscopic current deactivations that were about 60‐fold faster than wild‐type NR1a/NR2D receptors. Our results suggest that this conserved threonine residue plays a crucial role in ligand binding to NMDA NR2 receptor subunits and supports the idea that the slow decay kinetics associated with NR1a/NR2D NMDA receptors can be explained by the slow dissociation of glutamate from this NMDA receptor subtype.
KIT expression in fetal, normal adult, and neoplastic renal tissues
Authors: Miliaras D , Karasavvidou F , Papanikolaou A , Sioutopoulou D
Published: April 2004

Background:KIT is a transmembrane tyrosine kinase receptor, expressed in high amounts in various normal cells. In addition, c-kit mutation or activation is a major pathogenetic event in certain tumours (such as gastrointestinal stromal tumours). There are only limited data in the literature on the expression of KIT in normal and neoplastic renal tissues.

Aims:To investigate KIT expression in normal and neoplastic renal tissues.

Methods:KIT expression was evaluated by means of immunohistochemistry in paraffin wax embedded sections from 67 tissue samples.

Results:Eight of eight fetal kidneys, and 10 of 10 normal adult kidneys revealed cytoplasmic staining of renal tubules. The three cases of renal dysplasia studied expressed KIT in their normal and aberrant tubules. Two of 13 conventional renal cell carcinomas (RCCs), two of seven papillary type RCCs, four of seven chromophobe type RCCs, none of six nephroblastomas, seven of seven oncocytomas, two of two mesoblastic nephromas, and two of four angiomyolipomas were positive.

Conclusion:KIT is expressed in normal fetal and adult renal tubules, and in a subset of renal tumours. The expression of KIT in these renal tumours may prove to have diagnostic relevance and/or therapeutic implications.
SURROGATE ANALYSIS OF MULTICHANNEL DATA WITH FREQUENCY DEPENDANT TIME LAG
Authors: DOLAN KEVIN T.
Published: April 2004

Recently a new technique for generating linear surrogates of multichannel data was introduced. This technique, referred to as the coherent digitally filtered surrogate method, preserves both the individual power spectra, and the coherence function, of the original data. This method is somewhat limited in that it can only be applied to multichannel data in which the cross-spectrum is real. We present here an alteration to this algorithm that can be used to test any linear-correlation model, with arbitrary complex cross-spectra. This is of particular interest for experiments in which two channels are coupled with some time lag, and it is necessary to determine if the coupling is linear. We also demonstrate that this algorithm can be used along with the synchronization to provide a much better estimate for the degree of phase-locking between two signals than the coherence analysis techniques traditionally used in neuroscience.
Scaffold topography alters intracellular calcium dynamics in cultured cardiomyocyte networks
Authors: Yin Lihong , Bien Harold , Entcheva Emilia
Published: April 2004

Structural and functional changes ensue in cardiac cell networks when cells are guided by three-dimensional scaffold topography. We report enhanced synchronous pacemaking activity in association with slow diastolic rise in intracellular Ca2+concentration ([Ca2+]i) in cell networks grown on microgrooved scaffolds. Topography-driven changes in cardiac electromechanics were characterized by the frequency dependence of [Ca2+]iin syncytial structures formed of ventricular myocytes cultured on microgrooved elastic scaffolds (G). Cells were electrically paced at 0.5–5 Hz, and [Ca2+]iwas determined using microscale ratiometric (fura 2) fluorescence. Compared with flat (F) controls, the G networks exhibited elevated diastolic [Ca2+]iat higher frequencies, increased systolic [Ca2+]iacross the entire frequency range, and steeper restitution of Ca2+transient half-width ( n = 15 and 7 for G and F, respectively, P < 0.02). Significant differences in the frequency response of force-related parameters were also found, e.g., overall larger total area under the Ca2+transients and faster adaptation of relaxation time to pacing rate ( P < 0.02). Altered [Ca2+]idynamics were paralleled by higher occurrence of spontaneous Ca2+release and increased sarcoplasmic reticulum load ( P < 0.02), indirectly assessed by caffeine-triggered release. Electromechanical instabilities, i.e., Ca2+and voltage alternans, were more often observed in G samples. Taken together, these findings 1) represent some of the first functional electromechanical data for this in vitro system and 2) demonstrate direct influence of the microstructure on cardiac function and susceptibility to arrhythmias via Ca2+-dependent mechanisms. Overall, our results substantiate the idea of guiding cellular phenotype by cellular microenvironment, e.g., scaffold design in the context of tissue engineering.
Determination of the Location and Magnitude of Synaptic Conductance Changes in Spinal Motoneurons by Impedance Measurements
Authors: Maltenfort Mitchell G. , Phillips Carrie A. , McCurdy Martha L. , Hamm Thomas M.
Published: April 2004

The relation between impedance change and the location and magnitude of a tonic synaptic conductance was examined in compartmental motoneuron models based on previously published data. The dependency of motoneuron impedance on system time constant (τ), electrotonic length (L), and dendritic-to-somatic conductance ratio (ρ) was examined, showing that the relation between impedance phase and ρ differed markedly between models with uniform and nonuniform membrane resistivity. Dendritic synaptic conductances decreased impedance magnitude at low frequencies; at higher frequencies, impedance magnitude increased. The frequency at which the change in impedance magnitude reversed from a decrease to an increase—the reversal frequency, Fr—was a good estimator of electrotonic synaptic location. A measure of the average normalized impedance change at frequencies less than Fr, cuΔZ, estimated relative synaptic conductance. Fr and cuΔZ provided useful estimates of synaptic location and conductance in models with nonuniform (step, sigmoidal) and uniform membrane resistivity. Fr also provided good estimates of spatial synaptic location on the equivalent cable in both step and sigmoidal models. Variability in relations between Fr, cuΔZ, and conductance location and magnitude between neurons was reduced by normalization with ρ and τ. The effects on Fr and cuΔZ of noise in experimental recordings, different synaptic distributions, and voltage-dependent conductances were also assessed. This study indicates that location and conductance of tonic dendritic conductances can be estimated from Fr, cuΔZ, and basic electrotonic motoneuron parameters with the exercise of suitable precautions.
When is Vestibular Information Important During Walking?
Authors: Bent Leah R. , Inglis J. Timothy , McFadyen Bradford J.
Published: April 2004

Locomotion relies on vision, somatosensory input, and vestibular information. Both vision and somatosensory signals have been shown to be phase dependently modulated during locomotion; however, the regulation of vestibular information has not been investigated in humans. By delivering galvanic vestibular stimulation (GVS) to subjects at either heel contact, mid-stance, or toe-off, it was possible to investigate when vestibular information was important during the gait cycle. The results indicated a difference in the vestibular regulation of upper versus lower body control. Upper body responses to GVS applied at different times did not differ in magnitude for the head ( P = 0.2383), trunk ( P = 0.1473), or pelvis ( P = 0.1732) showing a similar dependence on vestibular information for upper body alignment across the gait cycle. In contrast, foot placement was dependent on the time when stimulation was delivered. Changes in foot placement were significantly larger at heel contact (during the double support phase) than when stimulation was delivered at mid-stance (in the single support phase of the gait cycle; P = 0.0193). These latter results demonstrate, for the first time, evidence of phase-dependent modulation of vestibular information during human walking.
Integral representation of the solutions to Heun′s biconfluentequation
Authors: Belmehdi S. , Chehab J.-P.
Published: April 2004

First, we trace the genesis of the canonical form of Heun′s
biconfluent equation. Second, we present a method which allows us
to find an integral expression as a solution to our
equation, and finally, using the properties of Meijer
G‐functions, we give an integral representation of a
fundamental system of solutions to the biconfluent equation.
Automatic Discrimination of Abnormal SubjectsUsing the Visual Evoked Potential Spectral Components
Authors: Sivakumar R. , Ravindran G.
Published: April 2004

Study of visual evoked potential (VEP) is one of the utilized
methods in clinical diagnosis of ophthalmology and neurological
disorders. The automatic detection of VEP spectral components is
an important tool in the diagnosis of mental activity. This paper
presents a novel computational approach using feedforward neural
network to identify abnormal subjects from changes in spectral
components. The output vector from the feedforward neural network
is based on the VEP spectral components. The software was
developed to identify mental state from the VEP spectral
components using Matlab software package. Using this approach, it
is possible to perform real‐time abnormality identification
accurately on personal computers.
Deep Vein Thrombosis Resolution Is Modulated by Monocyte CXCR2-Mediated Activity in a Mouse Model
Authors: Henke Peter K. , Varga Andrea , De Sumit , Deatrick C. Barry , Eliason Jonathon , Arenberg Douglas A. , Sukheepod Pasu , Thanaporn Porama , Kunkel Steven L. , Upchurch Gilbert R. , Wakefield Thomas W.
Published: April 2004

Objective—To determine the role of CXCR2, the receptor for cysteine-X-cysteine (CXC) chemokines, and its primary effector cell, the neutrophil (PMN), on deep venous thrombosis (DVT) resolution.

Methods and Results—DVT in BALB/c, anti-CXCR2 antibody-treated, and BALB/c CXCR2−/−mice were created by infrarenal inferior vena cava (IVC) ligation and the thrombus harvested at various time points over 21 days. The CXCR2−/−mice had significantly larger thrombi at early time points (days 2 to 8), and significantly decreased intrathrombus PMNs, monocytes, and neovascularization as compared with controls. Thrombus KC/CXCL1 was significantly higher at 2 days in CXCR2−/−thrombi as measured by enzyme-linked immunosorbent assay. Fibrin content was significantly higher, with less uPA gene expression at 4 days in CXCR2−/−thrombi. Late fibrotic maturation of the thrombus was delayed in the CXCR2−/−mice, with significantly decreased 8 day MMP-2 activity, whereas MMP-9 activity was elevated as compared with controls. Similar impairment in DVT resolution was found at 8 days with anti-CXCR2 inhibition. However, systemic neutropenia, unlike CXCR2 deletion, did not increase the thrombus size as compared with controls.

Conclusions—Normal DVT resolution involves CXCR2-mediated neovascularization, collagen turnover, and fibrinolysis, and it is probably primarily monocyte-dependent.
Blood Pressure Differences Between Northern and Southern Chinese: Role of Dietary Factors
Authors: Zhao Liancheng , Stamler Jeremiah , Yan Lijing L. , Zhou Beifan , Wu Yangfeng , Liu Kiang , Daviglus Martha L. , Dennis Barbara H. , Elliott Paul , Ueshima Hirotsugu , Yang Jun , Zhu Liguang , Guo Dongshuang
Published: April 2004

Blood pressure and prevalence of high blood pressure are greater for northern than southern Chinese. Reasons for these differences are unclear. Relationships of north–south blood pressure differences with multiple dietary factors were investigated in 839 Chinese participants, International Study on Macronutrients and Blood Pressure (INTERMAP), 561 northern, 278 southern, aged 40 to 59 years. Daily nutrient intakes were determined from four 24-hour dietary recalls and 2 timed 24-hour urine collections. Average systolic/diastolic pressure levels were 7.4/6.9 mm Hg higher for northern than southern participants. Southern participants had lower body mass index, sodium intake, sodium/potassium ratio, and higher intake of calcium, magnesium, phosphorus, and vitamins A and C. Considered singly, with control for age and gender, several dietary variables (eg, body mass index, urinary sodium/potassium ratio, urinary sodium, dietary phosphorus, and magnesium) reduced north–south blood pressure differences by ≥10%. Controlled for age and gender, nondietary variables had little effect on north–south blood pressure differences. With inclusion in regression models of multiple dietary variables (sodium, potassium, magnesium or phosphorus, body mass index), north–south blood pressure differences became much smaller (systolic −1.1, diastolic 1.6 mm Hg) and statistically nonsignificant. In conclusion, multiple dietary factors accounted importantly for north–south blood pressure differences. Efforts are needed to improve nutrition in China, especially in the north, as well as in other populations including those in the United States, for prevention and control of adverse blood pressure levels and major adult cardiovascular disease.