bluuebunny/crossref_metadata_2025_split huggingface dataset:
Laddering
Authors: Rugg G. , McGeorge P. 
Published: May 2007

Abstract: There is still a need for new knowledge elicitation techniques and tools. Laddering is a technique which has a long history in a wide range of disciplines and which has proved extremely useful in knowledge elicitation. There have, however, been few attempts to describe and survey the technique per se. This paper describes the technique, its background, its use, analysis, and automation, with particular reference to knowledge elicitation. The advantages and disadvantages of the technique are described. It is concluded that laddering is a valuable technique which could be used in a wide range of settings.
A generic, object‐oriented case‐knowledge representation scheme, and its integration into a wider information management scenario
Authors: Dubitzky Werner , Bell David , Hughes John 
Published: May 2007

Abstract:A knowledge base management system (KBMS) realises a combination of techniques found in database management systems and knowledge‐based systems. At the data model and knowledge representation level, many systems of this kind constitute a marriage of the relational data model and the rule‐based reasoning. Experience has shown that either approach is restricted in the way it can express the demanding information and knowledge structures required for applications like decision support systems. Two new technologies offer an exciting new integrated approach to knowledge management. Object‐oriented database management systems (OODBMS) provide an object model that supports powerful abstraction mechanisms to facilitate the modelling of highly structured information. Whereas case‐based reasoning (CBR) systems are knowledge bases which organise their capabilities around a memory of past cases and the notion of similarity. Both types of system are built upon two fundamental concepts: 1) the retrieval of entities with potentially complex structure, called objects in the former, and cases in the latter type of system; 2) the organisation of those entities in collections with common characteristics. In an OODBMS such collections are termed extents, and in CBR they are usually called categories. In either system, the conceptual meta notion to represent both, objects as well as extents, and cases as well as categories, is the class.Revolving around a Conceptual Case Class and extending a standard object model, this paper proposes a novel and general approach to represent case‐knowledge and to build KBMSs. The work presented here is a spin‐off of the design of an object query language within the ESPRIT project Lynx.
Evidence for an Association of the Dopamine D5 Receptor Gene on Age at Onset of Attention Deficit Hyperactivity Disorder
Authors: Lasky‐Su J. , Biederman J. , Laird N. , Tsuang M. , Doyle A. E. , Smoller J. W. , Lange C. , Faraone S. V. 
Published: May 2007

SummaryThe purpose of this study was to determine whether the single nucleotide polymorphisms (SNPs) within candidate genes for attention deficit hyperactivity disorder (ADHD) are associated with the age at onset for ADHD. One hundred and forty‐three SNPs were genotyped across five candidate genes (DRD5,SLC6A3,HTR1B,SNAP25,DRD4) for ADHD in 229 families with at least one affected offspring. SNPs with the highest estimated power to detect an association with age at onset were selected for each candidate gene, using a power‐based screening procedure that does not compromise the nominal significance level. A time‐to‐onset analysis for family‐based samples was performed on these SNPs to determine if an association exists with age at onset for ADHD. Seven consecutive SNPs surrounding the D5 dopamine receptor gene (DRD5), were associated with the age at onset for ADHD; FDR adjusted q‐values ranged from 0.008 to 0.023. This analysis indicates that individuals with the risk genotype develop ADHD earlier than individuals with any other genotype. A haplotype analysis across the 6 significant SNPs that were in linkage disequilibrium with one another,CTCATA, was also found to be significant (p‐value = 0.02). We did not observe significant associations with age at onset for the other candidate loci tested. Although definitive conclusions await independent replication, these results suggest that a variant inDRD5may affect age at onset for ADHD.
A comparative study of proteasomal inhibition and apoptosis induced in N27 mesencephalic cells by dopamine and MG132
Authors: Zafar Khan Shoeb , Inayat‐Hussain Salmaan H. , Ross David 
Published: May 2007

AbstractDopamine (DA) and its metabolites have been implicated in the pathogenesis of Parkinson’s disease. DA can produce reactive‐oxygen species and DA‐derived quinones such as aminochrome can induce proteasomal inhibition. We therefore examined the ability of DA and MG132 to induce apoptosis and proteasomal inhibition in N27 rat dopaminergic cells. DA (0–500 μmol/L, 0–24 h) and MG132 (0–5 μmol/L, 0–24 h) treated N27 cells resulted in time‐ and concentration‐dependent apoptosis. To better define DA and MG132‐induced apoptosis, the activation of initiator caspases 2 and caspase 9 and the executioner caspase 3 was investigated. Activation of caspase 2, caspase 9, and caspase 3 occurred early and prior to cell death. In addition, N‐acetylcysteine (NAC) blocked DA but not MG132‐induced apoptosis and mitochondrial membrane potential loss. NAC can react with both reactive‐oxygen and quinoid metabolites and its inhibitory activity suggests a role for reactive species in DA‐induced apoptosis. Proteasomal inhibition was detected after DA treatment in N27 cells which occurred prior to cell death and was abrogated by NAC. Our results implicate DA‐derived reactive species in proteasomal inhibition and caspase‐dependent apoptosis in N27 cells. The ability of endogenous DA‐derived metabolites to induce proteasomal inhibition and apoptosis may contribute to the selective loss of dopaminergic neurons in Parkinson’s disease.
Glutamine uptake by System A transporters maintains neurotransmitter GABA synthesis and inhibitory synaptic transmission
Authors: Fricke Molly N. , Jones‐Davis Dorothy M. , Mathews Gregory C. 
Published: May 2007

AbstractGABA synthesis is necessary to maintain synaptic vesicle filling, and key proteins in its biosynthetic pathways may play a role in regulating inhibitory synaptic stability and strength. GABAergic neurons require a source of precursor glutamate, possibly from glutamine, although it is controversial whether glutamine contributes to the synaptic pool of GABA. Here we report that inhibition of System A glutamine transporters with α‐(methyl‐amino) isobutyric acid rapidly reduced the amplitude of inhibitory post‐synaptic currents and miniature inhibitory post‐synaptic currents (mIPSCs) recorded in rat hippocampal area cornu ammonis 1 (CA1) pyramidal neurons, indicating that synaptic vesicle content of GABA was reduced. After inhibiting astrocytic glutamine synthesis by either blocking glutamate transporters or the glutamine synthetic enzyme, the effect of α‐(methyl‐amino) isobutyric acid on mIPSC amplitudes was abolished. Exogenous glutamine did not affect mIPSC amplitudes, suggesting that the neuronal transporters are normally saturated. Our findings demonstrate that a constitutive supply of glutamine is provided by astrocytes to inhibitory neurons to maintain vesicle filling. Therefore, glutamine transporters, like those for glutamate, are potential regulators of inhibitory synaptic strength. However, in contrast to glutamate, extracellular glutamine levels are normally high. Therefore, we propose a supportive role for glutamine, even under resting conditions, to maintain GABA vesicle filling.
Peristerite compositions in quartzofeldspathic schists, Franz Josef‐Fox Glacier Area, New Zealand
Authors: GRAPES RODNEY , OTSUKI MASAYUKI 
Published: May 2007

Plagioclase compositions vary from An0.1–2.5 to An32 with increasing grade in chlorite zone to oligoclase zone quartzofeldspathic schists, Franz Josef‐Fox Glacier area, Southern Alps, New Zealand. This change is interrupted by the peristerite composition gap in rocks transitional between greenschist and amphibolite facies grade. Oligoclase (An20‐24) and albite (An0.1–0.5) are found in biotite zone schists below the garnet isograd. With increasing grade, the plagioclase compositions outline the peristerite gap, which is asymmetric and narrows to compositions of An12 and An6 near the top of the garnet zone. In any one sample, oligoclase is the stable mineral in mica‐rich layers above the garnet isograd, whereas albite and oligoclase exist in apparent textural equilibrium in adjacent quartz‐plagioclase layers. The initial appearance of oligoclase in both layers results from the breakdown of epidote and possibly sphene. Carbonate is restricted to the quartz‐plagioclase rich layers and probably accounts for the more sodic composition of oligoclase in these layers. The formation of more Ca‐rich albite and more Na‐rich oligoclase near the upper limit of the garnet zone coincides with the disappearance of carbonate and closure of the peristerite gap. Garnet appears to have only a localized effect on Ca‐enrichment of plagioclase in mica‐rich layers within the garnet zone. The Na‐content of white mica increases sympathetically with increasing Ca‐content of oligoclase and metamorphic grade.Comparison of the peristerite gap in the Franz Josef‐Fox Glacier schists and schists of the same bulk composition in the Haast River area, 80 km to the S, indicates that oligoclase appears and epidote disappears at lower temperatures, and that the composition gap between coexisting albite and oligoclase is narrower in the Franz Josef‐Fox Glacier area. It is suggested that a higher thermal gradient (38‐40°C/km) and variations in Si/Al ordering during growth of the plagioclases between the two areas may account for these differences. In the Alpine schists the peristerite gap exists over a temperature and pressure interval of about 370‐515°C and 5.5‐7 kbar (550‐700 MPa) PH2O.
A tectonic model for the metamorphic evolution of the Basal Gneiss Complex, Western South Norway
Authors: CUTHBERT S. J. , HARVEY M. A. , CARSWELL D. A. 
Published: May 2007

A review of currently available information relevant to the Basal Gneiss Complex (BGC) of Western South Norway, combined with the authors’own observations, leads to the following conclusions.1. Most of the BGC consists of Proterozoic crystalline rocks and probably subordinate Lower Palaeozoic cover.2. The last major deformation of these rocks was during the Caledonian orogeny and involved large‐scale thrusting, recumbent folding and doming. The structural development of the BGC is closely tied in with that of the Caledonian allochthon.3. The whole eclogite‐bearing part of the BGC has suffered a high pressure metamorphism with conditions of between 550°C, 12.5 kbar (Sunnfjord) and about 750°C, 20 kbar (Møre og Romsdal) at the metamorphic climax.4. This metamorphism was of Caledonian age, probably rather early in the Caledonian tectonic history of the BGC and is considered to have been a rather transient event.By setting these conclusions in a framework provided by geophysical evidence for the deep structure of the crust in southern Norway we have constructed a geotectonic model to explain the recorded metamorphic history of the BGC. It is suggested that considerable crustal thickening was caused by imbrication of the Baltic plate margin during continental collision with the Greenland plate. This resulted in high pressure metamorphism in the resulting nappe stack. Progradation of the suture caused underthrusting of the Baltic foreland below the eclogite‐bearing terrain causing it to emerge at the Earth's surface, aided by tectonic stripping and erosion.Application of isostacy equations to the model shows that eclogites can be formed by in‐situ metamorphism in crustal rocks and reappear at the land surface above a normal thickness of crust in a single orogenic episode of approximately 65‐70 Ma duration.
Deformation and metamorphism in the Bard area of the Sesia Lanzo Zone, Western Alps, during subduction and uplift
Authors: WILLIAMS P. F. , COMPAGNONI R. 
Published: May 2007

The structure, microstructure and petrology of a small area close to the village of Bard in Val d'Aosta (Italy) has been studied in detail. The area lies across the contact between the Gneiss Minuti (GM) and the Eclogitic Micaschist (EMS) Complexes of the Lower element of the Sesia portion of the Sesia‐Lanzo Zone (Western Alps). Both complexes have undergone high‐pressure metamorphism, but the metamorphic assemblages indicate a sudden increase in pressure in going across the contact from the GM to the EMS. Therefore, we interpret the contact as a thrust dividing the lower element of the Sesia into two sub‐elements. This interpretation is supported by structural evidence.The early Alpine (90‐70 Ma) metamorphic history is best preserved in the EMS and is one of increasing pressure associated with thrusting. The maximum P/T recorded in the EMS is >1500 MPa (>15kbar) and 550°C and in the GM is < 1500‐1300 MPa (< 15‐13 kbar) and 500‐550°C. We suggest that the rocks were probably in an active Benioff zone during this time.From then on the histories of the GM and EMS are the same. Deformation continued and the thrust and thrust slices were folded during decreasing pressure. We interpret the first postthrusting deformation in terms of uplift associated with continued shortening of the crust and underplating after the Benioff zone had become inactive and a new Benioff zone had developed further to the north‐west.A still later deformation and the Lepontine metamorphism (38 Ma) are related to continued uplift. Much of this deformation is characterized by structures indicative of vertical shortening and lateral spreading as the mountains rose above the general level of the surface.
Petrology of pelitic schists in the oligoclase‐biotite zone of the Sanbagawa metamorphic terrain, Japan: phase equilibria in the highest grade zone of a high‐pressure intermediate type of metamorphic belt
Authors: ENAMI M. 
Published: May 2007

The oligoclase‐biotite zone of the Bessi area, central Shikoku is characterized by sodic plagioclase (XCa= 0.10–0.28)‐bearing assemblages in pelitic schists, and represents the highest‐grade zone of the Sanbagawa metamorphic terrain. Mineral assemblages in pelitic schists of this zone, all with quartz, sodic plagioclase, muscovite and clinozoisite (or zoisite), are garnet + biotite + chlorite + paragonite, garnet + biotite + hornblende + chlorite, and partial assemblages of these two types. Correlations between mineral compositions, mineral assemblages and mineral stability data assuming PH2O = Psolid suggests that metamorphic conditions of this zone are about 610 ± 25°C and 10 ± 1 kbar.Based upon a comparative study of mineralogy and chemistry of pelitic schists in the oligoclase‐biotite zone of the Sanbagawa terrain with those in the New Caledonia omphacite zone as an example of a typical high‐pressure type of metamorphic belt and with those in a generalized‘upper staurolite zone’as an example of a medium‐pressure type of metamorphic belt, progressive assemblages within these three zones can be related by reactions such as:
Cordierite‐bearing schists and gneisses from Timor, eastern Indonesia: P‐T conditions of metamorphism and tectonic implications
Authors: BROWN MICHAEL , EARLE MICHAEL M. 
Published: May 2007

In the Boi Massif of Western Timor the Mutis Complex, which is equivalent to the Lolotoi Complex of East Timor, is composed of two lithostratigraphical components: various basement schists and gneisses; and the dismembered remnants of an ophiolite. Cordierite‐bearing pelitic schists and gneisses carry an early mineral assemblage of biotite + garnet + plagioclase + Al‐silicate, but contain no prograde muscovite; sillimanite occurs in a textural mode which suggests that it replaced and pseudomorphed kyanite at an early stage and some specimens of pelitic schist contain tiny kyanite relics in plagioclase. Textural relations between, and mineral chemistries of, ferro‐magnesian phases in these pelitic chists and gneisses suggest that two discontinuous reactions and additional continuous compositional changes have been overstepped, possibly with concomitant anatexis, as a result of decrease in Pload during high temperature metamorphism. The simplified reactions are: garnet and/or biotite + sillimanite + quartz + cordierite + hercynite + ilmenite + excess components. P‐T conditions during the development of the early mineral assemblage in the pelitic gneisses are estimated to have been P + 10 kbar and T > 750°C, based upon the plagioclase‐garnet‐Al‐silicate‐quartz geobarometer and the garnet‐biotite geothermometer. P‐T conditions during the subsequent development of cordierite‐bearing mineral assemblages in the pelitic gneisses are estimated to have been P + 5 kbar and T + 700°C with XH2O < 0.5, based upon the Fe content of cordierite occurring in the assemblage quartz + plagioclase + sillimanite + biotite + garnet + cordierite coexisting with melt.Final equilibration between some of the phases suggests that conditions dropped to P > 2.3 kbar and T > 600°C. A similar exhumation P‐T path is suggested for the pelitic schists with early metamorphic conditions of P > 6.2 kbar and T > 745°C and subsequent development of cordierite under conditions in the range P = 3‐4 kbar and T = 600‐700°C. The tectonic implications of these P‐T estimates are discussed and it is concluded that the P‐T path followed by these rocks was caused by decompression during rifting and synmetamorphic ophiolite emplacement resulting from processes during the initiation and development of a convergent plate junction located in Southeast Asia during late Jurassic to Cretaceous time.
Contrasting textures in metamorphic and anatectic migmatites: an example from the Scottish Caledonides
Authors: McLELLAN E. L. 
Published: May 2007

Abstract.A method for the quantitative analysis of the spatial relations of minerals is described. Dispersed distributions are formed by annealing and destroyed in post‐tectonic migmatization. Aggregate distributions characterize solid‐state differentiation, whereas leucosomes formed in systems of high fluid:rock ratio (in the examples studied, anatectic melts) show random distributions.Quantitative textural analysis can be used to indicate whether migmatization was post‐tectonic or earlier, though caution is necessary if post‐migmatite cooling is slow or if there is some minor deformation. More importantly, it can be used to discriminate melt‐present from melt‐absent leucosomes; this is exemplified by a suite of metamorphic and anatectic migmatites from the Scottish Caledonides.The textural evolution of anatexites with increasing melt percentage is traced. Initial feldspar porphyroblastesis occurs by Ostwald ripening via grain boundary melts; subsequently ophthalmites develop with fabrics and chemistry inherited from the palaeosome. At greater than 30% melt these inherited fabrics are wholly destroyed. Deformation prompts segregation into melanosome and leucosome; resultant leucosomes contain no inherited crystals. The scale of anatectic systems is fixed at the point at which segregation begins; ophthalmites provide evidence for melt and crystal transfer beyond original palaeosome boundaries. In contrast, metamorphic migmatites are necessarily small‐scale systems because of diffusive constraints, and melanosomes are invariably produced.
Mineral parageneses in metamorphic rocks exposed along Tailuko Gorge, Central Mountain Range, Taiwan*
Authors: ERNST W. G. 
Published: May 2007

Field, petrographic and microprobe investigations of metaclastic rocks, calcareous schists, marbles, chloritic calcareous meta‐volcanic units and schists/paragneisses which crop out along the eastern portion of the Central East‐West Cross Island Highway in Taiwan demonstrate that metamorphic intensity gradually increases eastward. The lower greenschist facies Slate Formation on the W contains completely recrystallized, pure albitic plagioclase, but at least some of the white micas (± chlorites) probably represent relict detrital flakes. Neo‐blastic biotite and epidote occur sporadically in the Pihou(?) Formation, and increase dramatically eastward; concomitantly the abundance of carbonaceous matter decreases to zero in the eastern Tailuko zone, and the amount of chlorite + white mica diminishes somewhat. Epidote becomes more aluminous at higher metamorphic grade. Eastward, phengites change progressively to more muscovitic compositions as the proportion of biotite increases.A close approach to chemical equilibrium for the pre‐Cenozoic, complexly deformed metamorphic basement assemblages is suggested by regular, systematic, major and minor element partitioning between analysed coexisting phases. Fractionation is less pronounced on the E, reflecting higher temperatures. Estimated physical conditions of recrystallization with αH2O and αCO2 moderate, are: T > 325 ± 75°C, P > 3 kbar (W); T > 425 ± 75°C, P > 4kbar(E).The gradual eastward increase in metamorphic intensity from the Slate Formation through the Pihou(?) Formation and the three Tailuko zones, as well as the relict precursor textures in the pre‐Cenozoic layered basement rocks indicate that the observed paragenetic sequence could represent a synchronous Neogene recrystallization event, probably accompanying the Plio‐Pleistocene collision of the Asiatic continental margin and the Luzon (Coastal Range) andesitic arc.
A new geobarometer for the assemblage biotite‐muscovite‐chlorite‐quartz
Authors: POWELL ROGER , EVANS JANE A. 
Published: May 2007

The equilibrium thermodynamics of the reaction:And the equilibrium constant is composed of activities formulated using ideal mixing on sites. Consideration is given to the evaluation of uncertainties in pressures calculated using the geobarometer. Preliminary testing suggests that the geobarometer has considerable potential. Much wider testing is now required.
Reaction pathways during the progressive deformation of a blueschist metabasite: the role of chemical disequilibrium and restricted range equilibrium
Authors: RIDLEY JOHN , DIXON JOHN E. 
Published: May 2007

Abstract
There are discrete masses of un‐deformed metabasite within the blueschist series of the island of Syros. Greece. Around the margins of these masses are zonal sequences through rocks showing intracrystalline deformation but without a geometric fabric, to rocks with discrete and anastomosing shear zones, and finally to penetratively foliated rocks with isolated relics of the original undeformed texture. Textural relics suggest that this spatial sequence is at least qualitatively also a temporal sequence.This progressive shear zone deformation took place concurrently with a glaucophane‐epidote to eclogite reaction. The reaction pathways in the rocks that underwent the shear zone deformation can be compared with those in rocks of a similar composition that suffered a longer deformation history and show no relics of an undeformed parent. Although the final assemblages are in both cases the same, the pathways are different. These differences are in part related to reactions promoted by the change from local to bulk equilibrium on the onset of deformation in the rocks. They are also related to the crystallization and later breakdown during the sequence of progressive equilibration of a metastable phase, in this case an impure glaucophane.