bluuebunny/crossref_metadata_2025 huggingface dataset:
Structures of CsEuBr3 and its degradation product Cs2EuBr5·10H2O
Authors: Ehrenberg Helmut , Fuess Hartmut , Hesse Sabine , Zimmermann Jörg , von Seggern Heinz , Knapp Michael
Published: March 2007

CsEuBr3, caesium europium tribromide, crystallizes in an orthorhombic perovskite-type structure with an a
−
a
−
c
+ octahedral tilting scheme (GdFeO3 type). CsEuBr3 is unstable in air and one of the degradation products was identified as Cs2EuBr5·10H2O by single-crystal X-ray analysis and synchrotron powder diffraction. The Eu3+ ions on twofold rotational axes are coordinated by nine water molecules, and each water O atom is linked to two Br atoms by hydrogen bonds. The tricapped trigonal [EuO9] prisms are separated from each other by infinite {Cs2Br5·H2O} chains; the description Eu(OH2)9Cs2Br5(OH2) might therefore be more appropriate. The oxidation of Eu2+ to Eu3+ during the degradation of CsEuBr3 is further confirmed by changes in the magnetic properties from the as-prepared material into the degraded product.
Unravelling the chemical basis of the bathochromic shift in the lobster carapace; new crystal structures of unbound astaxanthin, canthaxanthin and zeaxanthin
Authors: Bartalucci Giuditta , Coppin Jennifer , Fisher Stuart , Hall Gillian , Helliwell John R. , Helliwell Madeleine , Liaaen-Jensen Synnøve
Published: March 2007

The crystal structures of the unbound carotenoids, synthetic astaxanthin (3S,3′S:3R,3′S:3R,3′R in a 1:2:1 ratio), canthaxanthin and (3R,3′S, meso)-zeaxanthin are compared with each other and the protein bound astaxanthin molecule in the carotenoprotein, β-crustacyanin. Three new crystal forms of astaxanthin have been obtained, using different crystallization conditions, comprising a chloroform solvate, a pyridine solvate and an unsolvated form. In each structure, the astaxanthin molecules, which are similar to one another, are centrosymmetric and adopt the 6-s-cis conformation; the end rings are bent out of the plane of the polyene chain by angles of −42.6 (5), −48.9 (5) and −50.4 (3)°, respectively, and are disordered, showing the presence of both R and S configurations (in a 1:1 ratio). In the crystal packing of the chloroform and pyridine solvates, the astaxanthin molecules show pair-wise end-to-end intermolecular hydrogen bonding of the adjacent 3-hydroxyl and 4-keto oxygens, whereas in the unsolvated crystal form, the hydrogen-bonding interaction is intermolecular. In addition, there are intermolecular C—H hydrogen bonds in all three structures. The canthaxanthin structure, measured at 100 and 293 K, also adopts the 6-s-cis conformation, but with disorder of one end ring only. The rotation of the end rings out of the plane of the polyene chains (ca −50 ° for each structure) is similar to that of astaxanthin. A number of possible C—H hydrogen bonds to the keto O atoms are also observed. (3R,3′S, meso)-zeaxanthin is centrosymmetric with a C5—C6—C7—C8 torsion angle of −74.9 (3)°; the molecules show pair-wise hydrogen bonding between the hydroxyl O atoms. In addition, for all the crystal structures the polyene chains were arranged one above the other, with intermolecular distances of 3.61–3.79 Å, indicating the presence of π-stacking interactions. Overall, these six crystal structures provide an ensemble of experimentally derived results that allow several key parameters, thought to influence colour tuning of the bathochromic shift of astaxanthin in crustacyanin, to be varied. The fact that the colour of each of the six crystals remains red, rather than turning blue, is therefore especially significant.
Octahedral As in M
+ arsenates – architecture and seven new members
Authors: Schwendtner Karolina , Kolitsch Uwe
Published: March 2007

Arsenates with arsenic in octahedral coordination are very rare. The present paper provides an overview of all known M
+ arsenates(V) containing octahedrally coordinated arsenic (M
+ = Li, Na, K, Rb, Cs, Ag) and the crystal structures (determined from single-crystal X-ray diffraction data) of the following seven new hydrothermally synthesized members belonging to six different structure types, four of which are novel: LiH2As3O9, LiH3As2O7, NaHAs2O6-type KHAs2O6, KH3As4O12 and isotypic RbH3As4O12, CsAs3O8 and NaH2As3O9-type AgH2As3O9. The main building unit of these compounds is usually an As4O14 cluster of two edge-sharing AsO6 octahedra sharing two apical corners each with two AsO4 tetrahedra. The different connectivity between these clusters defines the different structure types. The novel CsAs3O8 structure, based on a derivative of the As4O14 cluster, is the most condensed of all these M
+ arsenates, with an O/As ratio of only 2.67 compared with values of 2.75–3.5 for the remaining members. This is achieved through polymerization of the cluster derivatives to infinite chains of edge-sharing AsO6 octahedra. The [4]As/[6]As ratio drops to only 0.5. All but two of the protonated title compounds show protonated AsO6 octahedra. Hydrogen bonds range from very strong to weak. An analysis of bond-length distribution and average bond lengths in AsO6 octahedra in inorganic compounds leads to an overall mean As—O distance for all known AsO6 octahedra (with R factors < 0.072) of 1.830 (2) Å.
Structure and hydrogen bonding in 2,4-dihydroxybenzoic acid at 90, 100, 110 and 150 K; a theoretical and single-crystal X-ray diffraction study
Authors: Parkin Andrew , Adam Martin , Cooper Richard I. , Middlemiss Derek S. , Wilson Chick C.
Published: March 2007

A new polymorph of 2,4-dihydroxybenzoic acid is reported. The structure was characterized by multiple-temperature X-ray diffraction and solid-state DFT computations. The material shows a geometric pattern of hydrogen bonding consistent with cooperativity between the intermolecular carboxylic acid dimer and intramolecular hydrogen bonds. The presence of proton disorder within this hydrogen-bond system, which would support such a cooperative model, was not fully ruled out by the initial X-ray studies. However, solid-state calculations on the three possible end-point tautomers indicate that the dominant crystallographically observed configuration is substantially lower in energy than the other tautomers (by at least 9 kJ mol−1), indicating that no disorder should be expected. It is therefore concluded that no disorder is observed either in the intra- or intermolecular hydrogen bonds of the title compound and that the cooperativity between the hydrogen bonds is not present within the temperature range studied.
Order and disorder among the layered double hydroxides: combined Rietveld and DIFFaX approach
Authors: Radha A. V. , Kamath P. Vishnu , Shivakumara C.
Published: March 2007

A combined approach using the Rietveld technique of structure refinement and DIFFaX simulations of the powder patterns enables us to not only arrive at the complete structure of the layered double hydroxides (LDHs), but also classify and quantify the nature of structural disorder. Hydrolysis of urea dissolved in mixed-metal salt solutions containing a divalent metal (Mg2+, Co2+) with Al3+ results in the homogeneous precipitation of the corresponding LDH. The products obtained are highly crystalline enabling a complete structure determination including subsequent refinement by the Rietveld method. In contrast, the LDH of Ni2+ with Al3+ crystallizes with the incorporation of stacking faults. A combined Rietveld–DIFFaX approach shows that even `crystalline' samples of this LDH incorporate up to 9% of stacking faults, which are not eliminated even at elevated temperatures (473 K). These studies have implications for the order, disorder and `crystallinity' of layered phases in general and metal hydroxides in particular.
Synthesis and structural characterization of BaV4O9
Authors: Reeswinkel Thomas , Prinz Sebastian , Sparta Karine M. , Roth Georg
Published: March 2007

The new spin ½ V4+ barium oxovanadate BaV4O9 was synthesized and studied by means of single-crystal X-ray diffraction. Its room-temperature structure is monoclinic, space group P2/c. We discuss the temperature evolution of the crystal structure and thermal expansion tensor of the material between 293 and 100 K.
Tremor As a Cause of Pseudoatrial Flutter
Authors: Vanerio Gabriel
Published: March 2007

Muscle tremors mimicking atrial or ventricular arrhythmias are unusual. If present, however, misdiagnosis and consequently inappropriate treatments are possible. The authors present a patient with Parkinson's disease who was referred for evaluation of the need for oral anticoagulation because of persistent atrial flutter.
Community structure or function: effects of environmental stress on benthic macroinvertebrates at different spatial scales
Authors: FELD CHRISTIAN K. , HERING DANIEL
Published: March 2007

1. This study investigated the relation of benthic macroinvertebrates to environmental gradients in Central European lowland rivers. Taxonomic structure (taxa) and functional composition (metrics) were related to gradients at four different spatial scales (ecoregion, catchment, reach and site). The environmental variables at the catchment‐, reach‐ and site scales reflected the intensity of human impact: catchment and floodplain land use, riparian and floodplain degradation, flow regulation and river bank and bed modification.

2. Field surveys and GIS yielded 130 parameters characterising the hydromorphology and land use of 75 river sections in Sweden, the Netherlands, Germany and Poland. Two hundred and forty‐four macroinvertebrate taxa and 84 derived community metrics and biotic indices such as functional guilds, diversity and composition measures were included in the analysis.

3. Canonical Correspondence Analysis (CCA) and Redundancy Analysis (RDA) showed that hydromorphological and land use variables explained 11.4%, 22.1% and 15.8% of the taxa variance at the catchment (‘macro’), reach (‘meso’) and site (‘micro’) scales, respectively, compared with 14.9%, 33.2% and 21.5% of the variance associated with the derived metrics. Ecoregion and season accounted for 10.9% and 20.5% of the variance of the taxonomic structure and functional composition, respectively.

4. Partial CCA (pCCA) and RDA (pRDA) showed that the unique variance explained was slightly higher for taxa than for metrics. By contrast, the joint variance explained for metrics was much higher at all spatial scales and largest at the reach scale. Environmental variables explained 46.8% of metric variance and 32.4% of taxonomic structure.

5. Canonical Correspondence Analysis and RDA identified clear environmental gradients along the two main ordination axes, namely, land use and hydromorphological degradation. The impact of catchment land use on benthic macroinvertebrates was mainly revealed by the proportion of urban areas. At the reach scale, riparian and floodplain attributes (bank fixation, riparian wooded vegetation, shading) and the proportion of large woody debris were strong predictors of the taxonomic structure and functional composition of benthic macroinvertebrates. At the site scale, artificial substrata indicated human impact, particularly the proportion of macro‐ and mesolithal used for bank enforcement (rip–rap).

6. Our study revealed the importance of benthic macroinvertebrate functional measures (functional guilds, composition and abundance measures, sensitivity and tolerance measures, diversity measures) for detecting the impact of hydromorphological stress at different spatial scales.
Erythropoietin/erythropoietin receptor system is involved in angiogenesis in human neuroblastoma
Authors: Ribatti D , Poliani P L , Longo V , Mangieri D , Nico B , Vacca A
Published: March 2007

Aims:  Previous studies have shown that increased vascularity is associated with tumour progression in human neuroblastoma (NB). The involvement of erythropoietin (Epo) in tumour angiogenesis has also been reported. The aim of this study was to correlate microvascular density and Epo/Epo‐receptor (EpoR) expression in endothelial and tumour cells to the clinical stage of NB.

Methods and results:  Specimens of NB obtained from 20 patients were investigated immunohistochemically by using anti‐CD31, anti‐Epo and anti‐EpoR antibodies. The extent of angiogenesis was found to be up‐regulated in advanced disease. In keeping with this observation, Epo/EpoR expression in tumour and endothelial cells, respectively, was also highly correlated with the extent of angiogenesis and higher clinical stage.

Conclusions:  The correlation of Epo/EpoR expression with angiogenesis and tumour progression suggests the presence of a loop in the Epo–EpoR system. Epo is secreted by tumour cells and affects vascular endothelial cells via its receptor, promoting tumour angiogenesis in a paracrine manner. Data suggest that Epo represents an important mediator in NB angiogenesis. Understanding the mechanisms of NB angiogenesis provides the basis for a rational approach to the development of antiangiogenic therapy in patients affected by NB.
S100A1: a powerful marker to differentiate chromophobe renal cell carcinoma from renal oncocytoma
Authors: Li G , Barthelemy A , Feng G , Gentil‐Perret A , Peoc'h M , Genin C , Tostain J
Published: March 2007

Aims:  The common subtypes of renal tumours are conventional, papillary, chromophobe carcinoma and oncocytoma. The morphological differentiation between chromophobe carcinoma and oncocytoma may be difficult. The aim was to evaluate S100A1 as a new marker for the differentiation of the two subtypes.

Methods and results:  Thirty‐nine tumour samples [nine clear cell renal cell carcinomas (RCCs), six papillary RCCs, nine chromophobe RCCs and 15 oncocytomas] were studied. The protein expression of S100A1 was evaluated by immunohistochemistry. The gene expression of S100A1 was analysed by reverse transcriptase‐polymerase chain reaction. Nine oncocytomas showed strong immunoreactivity for S100A1. Four oncocytomas were scored as moderate and one as weak reactivity. In total, 14/15 (93%) of oncocytomas were considered to be immunopositive. In contrast, all nine chromophobe RCCs were considered to be immunonegative. There was a significant difference in the positive percentages of staining of S100A1 between these two subtypes (P < 0.01). S100A1 immunoreactivity was observed in 6/9 clear cell and 4/6 papillary carcinomas. The results of S100A1 gene expression corresponded well with the results of immunohistochemistry.

Conclusion:  S100A1 may be a potentially powerful marker to differentiate the chromophobe RCC from renal oncocytoma.
Lewis X oligosaccharides targeting to DC‐SIGN enhanced antigen‐specific immune response
Authors: Wang Jingxue , Zhang Yongmin , Wei Jing , Zhang Xiaoping , Zhang Bei , Zhu Zhenyuan , Zou Wei , Wang Yiqin , Mou Zhirong , Ni Bin , Wu Yuzhang
Published: March 2007

Dendritic cell‐specific intercellular‐adhesion‐molecule‐grabbing non‐integrin (DC‐SIGN) is a potential target receptor for vaccination purposes. In the present study, we employed Lewis X (Lex) oligosaccharides, which mimic natural ligands, to target ovalbumin (OVA) to human dendritic cells (DCs) via DC‐SIGN, to investigate the effect of this DC‐SIGN‐targeting strategy on the OVA‐specific immune response. We demonstrated that Lex oligosaccharides could enhance the OVA‐specific immune response as determined by enzyme‐linked immunospot assay (ELISPOT), intracellular interferon‐γ staining and 51Cr‐release assay. An almost 300‐fold lower dose of Lex‐OVA induced balanced interferon‐γ‐secreting cells compared to OVA alone. Furthermore, secretion of interleukin‐10, a reported mediator of immune suppression related to DC‐SIGN, was not increased by Lex‐OVA, either alone or together with sCD40L‐stimulated groups. A blocking antibody against DC‐SIGN (12507) reduced the numbers of interferon‐γ‐secreting cells during Lex‐OVA stimulation, yet it did not prevent Lex oligosaccharides from promoting the secretion of interleukin‐10 that was induced by ultra‐pure lipopolysaccharide. These results suggested that the strategy of DC‐SIGN targeting mediated by Lex oligosaccharides could promote a T‐cell response. This DC‐targeting may imply a novel vaccination strategy.
Reliability of pollen ratios for environmental reconstructions on the Tibetan Plateau
Authors: Herzschuh Ulrike
Published: March 2007

Aim  Pollen ratios are widely used to gain palaeovegetation and palaeoclimatic information from fossil pollen spectra, although their applicability has seldom been tested with modern pollen data. I used a data set of 113 lake‐surface sediments from the eastern Tibetan Plateau to test the reliability of several pollen ratios.

Location  The lake‐surface pollen spectra cover a wide range of vegetation types (temperate desert, temperate steppe, alpine desert, alpine steppe, high‐alpine meadow, sub‐alpine shrub, coniferous and mixed forest) and climatic conditions (mean July temperature, TJuly: 4.0–17.4°C; mean annual precipitation, Pann: 104–670 mm).

Methods  Lake‐surface sediments were analysed palynologically, and several pollen ratios were calculated. These ratios were interpreted with respect to vegetation and climatic conditions.

Results  The arboreal pollen sum (AP) was highest in samples from forested areas and was significantly correlated with Pann (r2 = 0.44). In non‐forested areas, samples from large lakes and from lakes surrounded by sparse vegetation had increased AP values, suggesting that AP is a useful vegetation density indicator. Artemisia/Chenopodiaceae (A/C) ratios were lowest in desert areas and were positively correlated with Pann (r2 = 0.25). The aridity pollen index was inappropriate for inferring (palaeo‐)climatic information from samples on the eastern Tibetan Plateau as it had no significant correlation with the environmental factors. Artemisia/Cyperaceae (A/Cy) ratios had a significant correlation with TJuly (r2 = 0.23), but only a weak correlation with Pann, which indicates that the A/Cy ratio is applicable as a temperature indicator. Furthermore, it is a valuable tool for the differentiation of high‐alpine meadow from steppe vegetation.

Main conclusions  AP sum, A/C ratio and A/Cy ratio are useful tools for qualitative and semi‐quantitative palaeoenvironmental reconstruction on the Tibetan Plateau; however, the results obtained should not be interpreted quantitatively.
Phylogeography and population structure of the saker falcon (Falco cherrug) and the influence of hybridization: mitochondrial and microsatellite data
Authors: NITTINGER FRANZISKA , GAMAUF ANITA , PINSKER WILHELM , WINK MICHAEL , HARING ELISABETH
Published: March 2007

Microsatellite as well as sequence analysis of the mitochondrial control region were applied to infer phylogeography and population genetic structure of the saker falcon (Falco cherrug). Furthermore, we compared the patterns of mitochondrial haplotypes with the variation of microsatellite alleles among the species of the hierofalcon complex (F. cherrug, Falco rusticolus, Falco biarmicus, Falco jugger) to test hypotheses on population history. Historical samples from museum specimens of F. cherrug were analysed together with samples from contemporary populations to investigate possible influences of hybrid falcons escaped from falconry on the genetic composition. In the mitochondrial DNA analysis, none of the four species represents a monophyletic group. Moreover, there are no clearly defined groups of haplotypes corresponding to taxonomic entities. In the microsatellite analysis most of the variation is shared between species and no clear differentiation by private alleles is found. Yet, with a Bayesian clustering method based on allele frequencies, a differentiation of F. cherrug, F. rusticolus and two geographic groups of F. biarmicus was detected. Results from both nuclear and mitochondrial markers are compatible with the previously postulated ‘Out of Africa’ hypothesis assuming an African origin of the hierofalcons. From an ancestral African population, F. cherrug, F. rusticolus and F. jugger split off in separate waves of immigration into Eurasia and South Asia. A combination of evolutionary processes, including incomplete lineage sorting as well as hybridization, may be responsible for the currently observed genetic patterns in hierofalcons.
Invasion of European pine stands by a North American forest pathogen and its hybridization with a native interfertile taxon
Authors: GONTHIER P. , NICOLOTTI G. , LINZER R. , GUGLIELMO F. , GARBELOTTO M.
Published: March 2007

It was recently reported that North American (NA) individuals of the forest pathogen Heterobasidion annosum were found in a single pine stand near Rome, in association with the movement of US troops during World War II. Here, we report on some aspects of the invasion biology of this pathogen in Italian coastal pinewoods, and on its interaction with native (EU) Heterobasidion populations. Spores of Heterobasidion were sampled using woody traps in pine stands along 280 km of coast around Rome. DNA of single‐spore colonies was characterized by two sets of nuclear and one set of mitochondrial taxon‐specific polymerase chain reaction primers. NA spores were found not only in a single site, but in many locations over a wide geographic area. Invasion occurred at an estimated rate of 1.3 km/year through invasion corridors provided by single trees, and not necessarily by sizable patches of forests. Within the 100‐km long range of expansion, the NA taxon was dominant in all pure pine stands. Because abundance of the EU taxon is low and identical among stands within and outside the area invaded by NA individuals, we infer that the exotic population has invaded habitats mostly unoccupied by the native species. Discrepancy between a mitochondrial and a nuclear marker occurred in 3.8% of spores from one site, a mixed oak‐pine forest where both taxa were equally represented. Combined phylogenetic analyses on nuclear and mitochondrial loci confirmed these isolates were recombinant. The finding of hybrids indicates that genetic interaction between NA and EU Heterobasidion taxa is occurring as a result of their current sympatry.
Exploring the neurophysiological basis of chest wall allodynia induced by experimental oesophageal acidification – evidence of central sensitization1
Authors: Willert R. P. , Delaney C. , Kelly K. , Sharma A. , Aziz Q. , Hobson A. R.
Published: March 2007

Abstract  In somatic models of central sensitisation (CS) allodynia develops following changes to somatic A‐β fibres, allowing these afferents which normally only process innocuous sensations to encode pain. The aim of this study was to determine whether somatic allodynia induced by visceral sensitisation occurs via N‐Methyl‐D‐Aspartate (NMDA) receptor mediated changes to the neurophysiological characteristics of somatic A‐β fibres. Twelve healthy subjects had oesophageal, chest wall and foot pain thresholds (PT) to electrical stimulation measured, and chest wall evoked potentials (CEP) recorded before and 30 minutes after distal oesophageal acidification on 2 separate visits. Intravenous ketamine (an NMDA receptor antagonist) or saline was given 30 minutes post acid with repeated oesophageal and chest wall PT measurements and CEP recordings. Distal oesophageal acidification reduced PT to electrical stimulation on the anterior chest wall (37 ± 10mA v 29 ± 7mA p = 0.01) and proximal oesophagus (46 ± 10mA v 33 ± 11mA p = 0.001) but not the foot (37 ± 25mA v 39 ± 23mA p = 0.12). The induction of chest wall somatic allodynia was accompanied by a reduction in the latency of the P1 (36 ± 3ms to 30 ± 4ms p = 0.016) and P2 (87 ± 7 ms to v 76 ± 7ms p = 0.049) components of the CEP. NMDA receptor antagonism reversed both visceral and somatic pain hypersensitivity but did not affect CEP latencies. These data provide objective neurophysiological evidence that CS contributes to the development of somatic allodynia following visceral sensitisation.
Transcription Levels of Endothelin‐1 and Endothelin Receptors are Associated with Age and Leaflet Location in Porcine Mitral Valves
Authors: Pedersen L. G. , Offenberg H. , Moesgaard S. G. , Thomsen P. D. , Pedersen H. D. , Olsen L. H.
Published: March 2007

The aim of the study was to investigate the expression levels of endothelin‐1 (ET‐1) and ETAand ETBreceptors (ETA‐R and ETB‐R) in porcine mitral valves and associate the transcription levels to age, leaflet location and deposition of mucopolysaccharides (MPS). Tissue samples from the chordal and inter‐chordal insertion area of the anterior mitral valve leaflet from 11 sows (≥2 years of age) and 10 slaughter pigs (approximately 6 months old) were obtained and the relative gene expression levels of ET‐1, ETA‐R and ETB‐R measured by semi‐quantitative real‐time PCR. A separate tissue sample was taken for histopathological grading of MPS deposition. The transcription levels of ET‐1 (P < 0.0001) and ETA‐R (P < 0.0004) were significantly higher in leaflets from the sows compared with slaughter pigs. The gene expression of ETB‐R was not associated to age (P = 0.38), but increased in chordal insertion areas compared with inter‐chordal areas (P = 0.01). The expression of ET‐1 and ETA‐R mRNA did not differ significantly between the two leaflet locations. The valve leaflets from sows had a significantly increased degree of MPS deposition compared with slaughter pigs upon histological examination (P = 0.04). In conclusion, an age‐related valvular degeneration is observed in porcine mitral valve leaflets and ET‐1 is suggested to be involved through action of both ETAand ETBreceptors.
Development of a Microarray for Studying Porcine Cytokine Production in Blood Mononuclear Cells and Intestinal Biopsies
Authors: Andersson M. , Berg M. , Fossum C. , Jensen‐Waern M.
Published: March 2007

A microarray for demonstration of a limited number of porcine cytokines was initiated. Polymerase chain reaction (PCR) products were synthesized for four house‐keeping genes, cyclophilin, β‐actin, hypoxanthine phosphoribosyltransferase (HPRT) and glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH), and the following cytokines: interleukin (IL)‐1β, IL‐4, IL‐6, IL‐8, IL‐10, IL‐12 p35, IL‐12 p40, IL‐18, interferon (IFN)‐α, IFN‐β, IFN‐γ, tumour necrosis factor (TNF)‐α, macrophage inhibition factor (MIF) and granulocyte/macrophage colony‐stimulating factor (GM‐CSF). Cytokine production was induced by incubation of porcine peripheral blood mononuclear cells (PBMC) with Concanavalin A (ConA) or oligodeoxynucleotide (ODN) 2216. RNA was isolated after 6 or 24 h from stimulated cells or unstimulated control cells and from intestinal biopsies. Cytokine expression was analysed using a 3‐DNA Array 350TM labelling kit from Genisphere. Data were normalized using external control genes and analysed with the genepix pro 5.0 software. All the cytokines could be induced in PBMC and expressed on the array and the cytokines IL‐6 and IFN‐α were also analysed at protein level. All but one cytokine were expressed in samples from intestinal biopsies. Densitometric analyses of PCR products of the house‐keeping genes were performed to validate the results from the microarray. Thus, this microarray will enable analyses of the cytokine profile during local and systemic infections in the pig.
Direct Measurements of Nitric Oxide Release in Relation to Expression of Endothelial Nitric Oxide Synthase in Isolated Porcine Mitral Valves
Authors: Moesgaard S. G. , Olsen L. H. , Aasted B. , Viuff B. M. , Pedersen L. G. , Pedersen H. D. , Harrison A. P.
Published: March 2007

The aim of this study was to measure the direct release of nitric oxide (NO) from the porcine mitral valve using a NO microelectrode. Furthermore, the expression and localization of endothelial nitric oxide synthase (eNOS) in the mitral valve was studied using immunohistochemistry, Western blotting and RT‐PCR. Results show that bradykinin increases NO release from mitral valves (ΔBradykinin: 33.71 ± 10.41 nm NO, P < 0.001, n = 10), whereas N‐nitro‐l‐arginine methyl esther (l‐NAME) decreases NO release when compared with basal level (Δl‐NAME: 82.69 ± 15.66 nm NO, P < 0.005, n = 4). Both protein and mRNA expression of eNOS in mitral valves and in isolated valvular endothelial cells suggest that the NO release is mainly associated with the mitral valve endothelium. It is concluded that direct NO release from porcine mitral valves coincides with eNOS expression. This study documents useful techniques for investigations into the role of local NO release in mitral valve diseases.
Pseudotumor of the omentum with a fishbone nucleus
Authors: Yamamoto Takatsugu , Hirohashi Kazuhiro , Iwasaki Hiroto , Kubo Shoji , Tanaka Yoshinori , Yamasaki Keiichi , Koh Masae , Uenishi Takahiro , Ogawa Masao , Sakabe Katsu , Tanaka Shogo , Shuto Taichi , Tanaka Hiromu
Published: March 2007

A 23‐year‐old Japanese man was admitted with a chief complaint of abdominal pain. He was previously healthy, and his past medical history was unremarkable. Local tenderness and rebound tenderness at McBurney’s point were elicited. Abdominal roentgenography was non‐diagnostic. Ultrasonography and computed tomography showed a tumor with a central core. Based on a diagnosis of appendicitis with omental inflammation or an omental tumor, laparotomy performed. Intraoperatively, no site of gastrointestinal perforation was detected; however, a 5‐cm omental granuloma was identified that proved to have a fishbone nucleus on pathological examination. The postoperative course was uneventful, and upper gastrointestinal endoscopy and barium enema were unremarkable. A large solitary omental pseudotumor is rare, and the clinical course in this case was atypical compared with the usual course of intestinal perforation by a foreign body and formation of an intra‐abdominal granuloma.
Association of a single nucleotide polymorphism in Wnt10bgene with bone mineral density
Authors: Usui Takahiko , Urano Tomohiko , Shiraki Masataka , Ouchi Yasuyoshi , Inoue Satoshi
Published: March 2007

Background:  Wnt signaling pathway regulates bone mineral density (BMD) through the lipoprotein receptor‐related protein (LRP)5, a receptor of this signaling. Recently, we and several groups have shown that genetic variations at the LRP5 gene locus are associated with osteoporosis. These data suggest that genetic variations in Wnt signaling genes may affect the pathogenesis of osteoporosis. To explore whether the Wnt signaling molecules are involved in the maturation of osteoblasts, we analyzed the expression levels of Wnt signaling genes, including LRP5, LRP6 and Wnt10b, in rat primary osteoblasts. Then, we studied an association of a single nucleotide polymorphism (SNP) in Wnt10b gene with BMD.

Methods:  Expression levels of LRP5, LRP6 and Wnt10b mRNA were analyzed during the culture course of rat primary osteoblasts by real‐time reverse transcription polymerase chain reaction (RT‐PCR). Association of the Wnt10b gene polymorphism at 1059C/T (His353His), that is the only coding SNP found in J‐SNP database with BMD, was examined in 221 postmenopausal Japanese women.

Results:  LRP5, LRP6 and Wnt10b mRNA were detected during the differentiation of rat primary osteoblasts. As an association study of the SNP in the Wnt10b gene, the subjects without the T allele (CC; n = 59) had significantly higher total body and lumbar BMD than the subjects bearing at least one T allele (TT + TC; n = 162) (total body, P = 0.0091; lumber spine, P = 0.0052).

Conclusion:  Wnt10b mRNA was expressed and regulated in rat primary osteoblasts. A genetic variation at the Wnt10b gene locus is associated with BMD, suggesting an involvement of the Wnt10b gene in the bone metabolism. SNP of Wnt signaling genes would serve to facilitate early diagnosis, treatment and prevention of osteoporosis.
ECONOMETRIC MODELS OF ASYMMETRIC PRICE TRANSMISSION
Authors: Frey Giliola , Manera Matteo
Published: March 2007

Abstract In this paper, we review the existing empirical literature on price asymmetries in commodities, providing a way to classify and compare different studies that are highly heterogeneous in terms of econometric models, type of asymmetries and empirical findings. Relative to the previous literature, this paper is novel in several respects. First, it presents a detailed and updated survey of the existing empirical contributions on price asymmetries in the transmission mechanism linking input prices to output prices. Second, this paper presents an extension of the traditional distinction between long‐run and short‐run asymmetries to new categories of asymmetries, such as: contemporaneous impact, distributed lag effect, cumulated impact, reaction time, equilibrium and momentum equilibrium adjustment path, regime effect, regime equilibrium adjustment path. Each empirical study is then critically discussed in the light of this new classification of asymmetries. Third, this paper evaluates the relative merits of the most popular econometric models for price asymmetries, namely autoregressive distributed lags, partial adjustments, error correction models, regime switching and vector autoregressive models. Finally, we use the meta‐regression analysis to investigate whether the results of asymmetry tests are not model‐invariant and find which additional factors systematically influence the rejection of the null hypothesis of symmetric price adjustment. The main results of our survey can be summarized as follows: (i) each econometric model is specialized to capture a subset of asymmetries; (ii) each asymmetry is better investigated by a subset of econometric models; (iii) the general significance of the F test for asymmetric price transmission depends mainly on characteristics of the data, dynamic specification of the econometric model, and market characteristics. Overall, our empirical findings confirm that asymmetry, in all its forms, is very likely to occur in a wide range of markets and econometric models.
Examining the Relationships Between Monitoring and Incentives in Corporate Governance*
Authors: Rutherford Matthew A. , Buchholtz Ann K. , Brown Jill A.
Published: March 2007

abstract  Agency theory focuses on monitoring and incentives as two solutions to agency problems. Prior research suggests that monitoring and incentives may act either as substitutes or as complements, and that the context of the agency relationship plays a major role in determining the direction of the relationship between them. In a corporate governance setting, we contend that board information and boards' usage of CEO control mechanisms are best viewed as complements. Thus, we hypothesize that boards' information gathering behaviour will be positively related to boards' usage of CEO control mechanisms. Using primary and secondary data from 149 US firms, we find that increases in boards' information gathering are associated with increases in boards' usage of managerial controls. These findings suggest that information and managerial control mechanisms act as complements in the governance context, and that boards take a variety of actions to protect the interests of shareholders.
Disability Support Pension Recipients: Who Gets Off (and Stays Off) Payments?
Authors: Cai Lixin , Vu Ha , Wilkins Roger
Published: March 2007

We use Centrelink payment records on Disability Support Pension (DSP) recipients over the period 1995 to 2002 to investigate individual transitions off payments. Our findings are consistent with the existence of a close correspondence between disability benefit receipt and labour market outcomes: entry to DSP via unemployment benefits is associated with substantially reduced prospects of exiting DSP, while employment during the DSP spell is associated with not only an increased probability of exiting DSP, but also more success in staying off payments once an exit has been made. A further finding of our analysis is that persons who exit DSP due to take‐up of employment have a relatively high rate of return to payments compared with persons who exit for other reasons, and indeed exhibit a high propensity to cycle off and on payments.
Advisers and Decisions 1976*
Authors: Kemp David
Published: March 2007

On 13 December 1975 the Liberal‐Country party coalition led by Malcolm Fraser conclusively won a double dissolution election with large majorities in the Senate and House of Representatives. The following year, 1976, was a year of policy debates – debates about economic policy, foreign policy, family policy, health policy (especially Medibank), uranium and the environment, human rights and Aboriginal land policy in particular. They were, in reality, political struggles over the direction of the country and the ideas and philosophy that would govern the course of policy. At the core of government there was an epic battle between the Prime Minister and the government's senior advisers in the Treasury, the Department of Foreign Affairs, and the Department of the Prime Minister and Cabinet. Significant battles over foreign policy were modest compared with struggles over economic policy and the quest to control inflation. Debate came to a head with a devaluation of the dollar in the face of official advice. Among the consequences were division of the Treasury and creation of the Department of Finance, greater independence of the Reserve Bank and a confirmation of the need for elected leaders to have their own political staffs.
The Development of Competitive Industries: The Role of State Government Actors
Authors: Wickham Mark
Published: March 2007

Despite widespread adoption of Porter's Industrial Cluster Theory as a policy development framework by federal and state governments over the past decade, Australia remains significantly below the OECD average in terms of its industries' economic contributions to real wealth creation (Brown 2000; OECD 1998). The major cause cited for this relatively poor performance has been inability of key government officials to implement effective industry policy that simultaneously avoids de facto protectionism and distortion of competition. This article provides an insight into the key policy decisions undertaken by the Tasmanian state government that coincided with development of an internationally successful shipbuilding industry in that state. As such, this article provides a reflection on policy initiatives that may be valuable for government officials elsewhere.
Interacting with Consumer Advocates
Authors: Field Chris
Published: March 2007

This article explores the role of consumer advocacy. Those involved in public policy formation and administration – regulators, governments and other public policy makers – share an interest in effective consumer advocacy. Those who make our laws, as well as those who are custodians of its adjudication, compliance, monitoring and enforcement, share a common position with many consumer advocates – they all work to advance the long‐term interests of consumers.
Case Study: Improving Customer Service at the NSW Registry of Births, Deaths and Marriages
Authors: Curry Gregory
Published: March 2007

The NSW Registry of Births, Deaths and Marriages met the challenge of increased customer demand by changing its approach to managing and allocating its resources. The Registry cut customer waiting times by 90% while dealing with 12% higher demand. This article shows how a public sector organisation can provide the level of customer service expected by the 21st century community without compromising its core business. The Registry used statistical and management tools to engage staff. The changes made were incremental, but achieved remarkable gains in performance.
Understanding Solitude: Young Children's Attitudes and Responses Toward Hypothetical Socially Withdrawn Peers
Authors: Coplan Robert J. , Girardi Alberta , Findlay Leanne C. , Frohlick Sherri L.
Published: March 2007

The goal of the present study was to explore young children's attitudes and responses to different forms of social withdrawal by eliciting responses to hypothetical vignettes. Participants included 137 children (49 boys, 88 girls) in kindergarten and grade 1 classes (Mage = 75.94 months, SD = 9.03) in Ottawa, Canada. Parents rated child characteristics, including shyness, unsociability and aggression. Children were also interviewed individually and presented with a series of hypothetical vignettes describing the behaviors of shy, unsociable, aggressive and socially competent children. In response to each vignette, children were asked a series of questions designed to assess their perceptions, attitudes and responses toward each child behavior. Results suggested that young children made surprisingly sophisticated distinctions between shyness and unsociability, demonstrating differences in terms of attributions of behavioral intent, liking and sympathetic responses. In addition, unsociable children evidenced a distinct pattern of responses to hypothetical peers. These findings add to the growing body of research distinguishing different forms of social withdrawal, and shed some light as to why unsociability in early childhood may not be so benign.
Victimization Within Mutually Antipathetic Peer Relationships
Authors: Card Noel A. , Hodges Ernest V. E.
Published: March 2007

Children's victimization experiences within relationships characterized by mutual animosity were examined among 210 6th‐ and 7th‐grade boys and girls. Participants reported that a greater proportion of mutual antipathies, relative to other peers, victimized them. Moreover, the receipt of victimization within antipathetic relationships was greater when the partner in the relationship was aggressive, physically strong, non‐victimized and had low levels of internalizing problems. Perceptions of victimization and levels of maladjustment were also found to be more strongly associated with victimization from mutual antipathies than with victimization from other peers. Together, these findings highlight the importance of studying victimization in the context of antipathetic relationships and contribute to an emerging literature on the developmental significance of these relationships.
Differential Treatment and Communicative Interactions: Why the Character of Social Interaction is Important
Authors: NIELSEN VIBEKE LEHMANN
Published: March 2007

Regulatory studies have traditionally focused on external political and administrative factors when explaining the behavior of regulatory inspectors. This is, however, only one part of the story about regulatory behavior. To understand the behavior of street‐level bureaucrats such as regulatory inspectors, it is essential to look not only at external political and administrative factors but also at the very interaction between the bureaucrat and the client. By focusing on differential treatment of regulated firms by inspectors and the explanatory power of the interaction between inspector and firm, the article shows that variation in the level of communication between inspector and regulatee helps to explain variation in regulatory leniency. The higher the level of communication, the more lenient is the inspector.
An ‘art’, not a ‘science’? Central bank management in Portugal under the gold standard, 1863–871
Authors: REIS JAIME
Published: March 2007

As long as Portugal was on the gold standard, the Bank of Portugal sought to help stabilize the currency at the exchange rate to which the country was committed. Because it was subject to political and other non‐economic constraints, the bank carried out discount rate interventions sparingly, although in accordance with what could be termed the contemporary ‘science’ of central banking. Consequently, it had to intervene frequently in the currency markets, usually in covert fashion, in order to conciliate the needs of convertibility with this less than orthodox stance towards the gold standard. This article also shows how the bank was able to keep on repeatedly infringing the ‘rules of the game’ with success for almost 30 years, and raises the question of the sustainability of such a state of affairs.
A Comparison of Alternative Non‐parametric Estimators of the Short Rate Diffusion Coefficient
Authors: Renò Roberto , Roma Antonio , Schaefer Stephen
Published: March 2007

In this paper we discuss the estimation of the diffusion coefficient in one‐factor models for the short rate via non‐parametric methods. We test the estimators proposed by Ait‐Sahalia (1996), Stanton (1997) and Bandi and Phillips (2003) on Monte Carlo simulations of the Vasicek and CIR model. We show that the Ait‐Sahalia estimator is not applicable for values of the mean reversion coefficient typically displayed by interest rate data, while the Stanton and Bandi–Phillips estimators perform better. Each of the three estimators depends crucially on the choice of the bandwidth parameter. Our analysis shows that the estimators give different results for both the data set analysed by Ait‐Sahalia (1996) and by Stanton (1997). Finally we show that the data sets used by Ait‐Sahalia and Stanton are inherently different and, in particular, that very short‐term data exhibit characteristics which are inconsistent with a diffusion.
Estimating the Term Structure of Credit Spreads on Euro‐denominated Corporate Bonds
Authors: Terazzan Ombretta
Published: March 2007

In this paper, we estimate the term structure of credit spreads on Euro‐denominated corporate bonds with a modified version of the Duffee (1999) intensity‐based model. The empirical analysis considers monthly observations for a sample of investment‐grade euro‐denominated corporate bonds analysed for rating classes. The model is estimated with a maximum likelihood – Kalman filter approach over different sample periods ranging from January 1999 to August 2006. The estimation results, in general, support the application of the theoretical model to the euro‐denominated bond market and exhibit some interesting characteristics of this relatively recent market.
Recasting the City into City‐Regions: Place Promotion, Competitiveness Benchmarking and the Quest for Urban Supremacy
Authors: GREENE FRANCIS J. , TRACEY PAUL , COWLING MARC
Published: March 2007

ABSTRACT This essay critically examines twenty‐two studies designed to measure the competitiveness of cities and city‐regions. We suggest that while this research may show statistical correlations between different dimensions of competitiveness, there is little in the way of causation. More fundamentally, our main point is to question the utility of such studies. Regional disparities in terms of wealth and living standards are well known; simply recasting the spatial scale to the city or the city‐region does not change the underlying fundamentals of regional performance.
Integrating Firm Dynamics into the Shift‐Share Framework
Authors: FOTOPOULOS GEORGIOS
Published: March 2007

ABSTRACT  This article integrates firm birth and death data into a shift‐share analysis framework. The proposed methodology can be used when data availability does not allow for the direct association of employment changes to business demographics at the regional level. It may be also used as an exploratory step before any explanatory econometric work is undertaken as a means of identifying classes of potential control variables. Applying the method to Greek data suggests that firm‐size heterogeneity should not be ignored, that local conditions matter more than regional economic structure, and that the latter are asymmetrical across sectors when it comes to the effects of business demographics on regional employment or output growth.
Exploring Access and Equity in Higher Education: Policy and Performance in a Comparative Perspective
Authors: Clancy Patrick , Goastellec Gaële
Published: March 2007

A comparative analysis of how access and equity are defined and how policies have evolved reveals a number of commonalities and differences between countries. The overall trend is a movement from the priority given to ‘inherited merit’ in the admission process through a commitment to formal equality, towards the application of some modes of affirmative action for selected under‐represented groups. This overall convergence, which is accompanied by a growing appreciation of the complexity of social identities, is complemented by significant national specificity in respect of the social categories which are used to define social diversity. In the absence of appropriate comparative measures of participation a Higher Education Participation Index is developed to facilitate cross‐country comparisons. A review of current attempts to measure equity in access to higher education points to the need to develop a programme of comparative research which focuses on the social characteristics of students who are currently enrolled in higher education.