bluuebunny/crossref_metadata_2025 huggingface dataset:
Meta-igneous granulite and ultramafic xenoliths from basalts of the Midland Valley of Scotland: petrology and mineralogy of the lower crust and upper mantle
Authors: Hunter Robert H. , Upton Brian G. J. , Aspen Peder
Published: November 2011

Ultramafic xenolith lithologies representative of the mantle beneath the Midland Valley of Scotland comprise magnesian peridotite (predominantly spinel lherzolite) and cumulate wehrlites and clinopyroxenites. The lherzolites are typical of the worldwide type I (Cr-diopside) xenolith suite; their textures and mineral chemistry record a complex thermal and deformational history. The petrographical and mineralogical features of the wehrlite-clinopyroxenite suite can be interpreted within the context of a sequence of cpx + ol ± sp cumulates that have undergone a protracted period of subsoli dus re-equilibration. Mineral compositions are similar to those of type II (Al-augite) ultramafic xenolith suites.

Although xenolith populations imply widespread lower crustal heterogeneity, meta-igneous basic granulites form a major component of this region beneath the Midland Valley. They are principally composed of pi + cpx + mt ± opx ± ap; a modal continuum exists from clinopyroxenite to anorthosite, skewed towards plagioclase-rich lithologies. Garnet is rare. Locally, evidence indicates re-equilibration from garnet granulite precursors. Rock densities range from c. 2·8 to c. 3·2 gm . cm−3, implying P-wave velocities in the range 6·5–7·5 km . s−1 consistent with the known seismic properties of the lower crustal layer beneath the Midland Valley. Phase relations are also consistent with equilibration of primary assemblages at depths of 20–35 km. Retrograde reactions indicate that portions of the crust may have had a complex pressure-temperature-time evolution. Major element compositions of the granulites are broadly basaltic, ranging from ne to hy normative with the mean corresponding to alkali olivine basalt. They are distinct, chemically, from basic granulites of the Lewisian complex of NW Scotland.
Crustal structure across the Caledonides from the ‘WINCH’ seismic reflection profile: influences on the evolution of the Midland Valley of Scotland
Authors: Hall J. , Brewer J. A. , Matthews D. H. , Warner M. R.
Published: November 2011

The Western Isles–North Channel (‘WINCH’) deep seismic reflection profile runs through the North Channel across the extension of the Midland Valley into the Firth of Clyde.

A variety of shallow Carboniferous and younger sedimentary basins dominates the upper crustal structure. The deep structure includes a reflective lower crust, bounded downwards by the Moho, and dipping ‘thrusts’. No margins to the Midland Valley are observed equivalent to the bounding faults on land. Thrusts below both the Highlands and the Southern Uplands have a variety of dip directions indicative of zig-zag crustal shortening of 100 km in the Highlands and 60 km in the Southern Uplands.

The Moho varies only a little in depth, despite the gross crustal deformation in the Caledonides. Isostatic recovery of the Moho on unlocking of collided crustal blocks may explain the formation of some sedimentary basins.
Geochemical evidence for the origins of igneous and sedimentary rocks of the Highland Border, Scotland
Authors: Robertson A. H. F. , Henderson W. G.
Published: November 2011

Narrow, intermittent, fault-bounded outcrops forming the largely Ordovician Highland Border Complex comprise terrigenous-derived turbidities, a dismembered ophiolite, and ophiolite-derived sediments.

New major- and trace-element analyses of the mafic igneous rocks confirm that two main groups exist. One, represented in outcrops the length of the Highland Boundary fault-zone, has a mostly MORB-like chemistry with some trace-element compositions conventionally pointing to genesis above a subduction zone. The other group, found more locally, has an alkalic ‘within-plate’ character. Amphibolites interpreted as ophiolitic ‘sole’ rocks are chemically similar to the MORB-type mafic extrusive rocks. X-ray diffraction of the sedimentary rocks reveals kaolinite to be widespread and this is attributed to tropical weathering of the Highland Border Complex beneath a (?mid-Devonian) unconformity surface. New major- and trace-element analyses show that the turbidities of the Highland Border Complex were derived from a terrigenous terrane similar to that which supplied the Dalradian Supergroup. Inter-lava sediments reflect varied terrigenous (distal turbidites), hydrothermal (iron oxide sediments), mafic extrusive (volcaniclastic silt) and biogenic (jaspers) provenances. The ophiolite-derived Highland Border Complex sediments also have a terrigenous component. Unlike, for example, the early Ordovician rocks of the South Mayo trough (Ireland), coeval differentiated volcanic material is not a significant component of the Complex.

No one existing model adequately explains all the available data. We favour an origin of the Complex in the Ordovician as a small Gulf of California-type marginal basin which was later tectonically emplaced in stages involving a long history of alternating extension, strike-slip and compression.
Constraints on genetic models for the Ballantrae complex, SW Scotland
Authors: Stone P.
Published: November 2011

The distribution of Arenig graptolite faunas and zones of differing metamorphic fades help to establish a polyphase imbrication history for the complex. A further complication is introduced by the presence within the imbricate stack of lava sequences of comparable age but with contrasting geochemical signatures of island-arc and oceanic island basalts, and oceanic island sequences of markedly different Arenig ages. Strike-slip mechanisms appear the most likely means of introducing such a disparate assortment of elements into the Ballantrae complex and an origin in a continental margin transform zone is preferred.
Metasomatism in the North Qôroq centre, South Greenland: cathodoluminescence and mineral chemistry of alkali feldspars
Authors: Rae D. A. , Chambers A. D.
Published: November 2011

The North Qôroq centre consists of a number of units of syenite, all undersaturated, with later units in sharp intrusive contact with earlier ones. Chemical and mineralogical characteristics have been determined by primary crystal-silicate liquid equilibria and also later, extensive, metasomatic alteration probably involving an alkali-rich aqueous phase. Cathodoluminescence studies on feldspars, the dominant phase present, reveal the development of red-luminescing albite in all the rocks affected by a late-stage fluid phase in contrast with the blue luminescence shown by unaltered perthites. Spectral and chemical investigation of the feldspars confirms earlier views that red luminescence is caused by Fe3+, an impurity in the feldspar structure, but also indicates that, for red luminescence to be seen, the blue luminescent peak must be greatly reduced or absent. The cause of the blue luminescence is less obvious but may well be related to an oxygen defect centre. Such a centre is apparently absent in red-luminescing albites and hence not formed during growth involving late-stage fluids. The fluids evolved from highly peralkaline, undersaturated magmas and metasomatised less evolved syenites forming feldspathoids, particularly sodalite. Once equilibrium had been attained the fluid behaved principally as a passive phase on its passage through the rocks, aiding the unmixing of the alkali feldspars.
The Peninsular Ranges Batholith: an insight into the evolution of the Cordilleran batholiths of southwestern North America
Authors: Silver L. T. , Chappell B. W.
Published: November 2011

The Peninsular Ranges Batholith of southern and Baja California is the largest segment of a Cretaceous magmatic arc that was once continuous from northern California to southern Baja California. In this batholith, the emplacement of igneous rocks took place during a single sequence of magmatic activity, unlike many of the other components of the Cordilleran batholiths which formed during successive separate magmatic episodes. Detailed radiometric dating has shown that it is a composite of two batholiths. A western batholith, which was more heterogeneous in composition, formed as a static magmatic arc between 140 and 105 Ma and was intrusive in part into related volcanic rocks. The eastern batholith formed as a laterally transgressing arc which moved away from those older rocks between 105 and 80 Ma, intruding metasedimentary rocks. Rocks of the batholith range from undersaturated gabbros through to felsic granites, but tonalite is the most abundant rock throughout. Perhaps better than elsewhere in the Cordillera, the batholith shows beautifully developed asymmetries in chemical and isotopic properties. The main gradients in chemical composition from W to E are found among the trace elements, with Ba, Sr, Nb and the light rare earth elements increasing by more than a factor of two, and P, Rb, Pb, Th, Zn and Ga showing smaller increases. Mg and the transition metals decrease strongly towards the E, with Sc, V and Cu falling to less than half of their value in the most westerly rocks. Oxygen becomes very systematically more enriched in18O from W to E and the Sr, Nd and Pb isotopic systems change progressively from mantle values in the W to a more evolved character on the eastern side of the batholith. In detail the petrogenesis of the Peninsular Ranges Batholith is not completely understood, but many general aspects of the origin are clear. The exposed rocks, particularly in the western batholith, closely resemble those of present day island arcs, although the most typical and average tonalitic composition is distinctly more felsic than the mean quartz diorite or mafic andesite composition of arcs. Chemical and isotopic properties of the western part of the batholith indicate that it formed as the root of a primitive island arc on oceanic lithosphere at a convergent plate margin. Further E, the plutonic rocks appear to have been derived by partial melting from deeper sources of broadly basaltic composition at subcrustal levels. The compositional systematics of the batholith do not reflect a simple mixing of various end-members but are a reflection of the differing character of the source regions laterally and vertically away from the pre-Cretaceous continental margin.
Isotope evidence for the origin of Andean granites
Authors: Pankhurst R. J. , Hole M. J. , Brook M.
Published: November 2011

The genesis of subduction-related magmas in the Andean region of South America and the Antarctic Peninsula is considered in relation to the Palaeozoic to Cenozoic granitoids belts which are thought to parallel palaeo-coastlines. Their Sr-Nd isotope systematics show a wide range of initial compositions (87Sr/86Sr0 0·7038 to >0·710; εNd, +4 to –10) requiring material input from both depleted mantle and continental crust. In local transects there are consistent trends with time of emplacement, from enriched (crustal) to depleted (mantle) sources, regardless of the sense of migration of magmatism (towards or away from the continent). These trends represent mixing between mantle-derived material and anatectic melts of the lower crust: in each case the crustal end-member reflects the age and isotopic composition of the local deep crustal basement (Precambrian in the easternmost Andes, Palaeozoic in the W and in the Antarctic Peninsula). The depleted end-member could be derived by melting within the subducted oceanic crust, the overlying mantle or previously crystallised mafic underplating. One of the most important factors controlling the mixing process is the angle of subduction, resulting in magma generation under variable tectonic conditions.
Crustal melting and granite genesis during the Himalayan collision orogenesis
Authors: France-Lanord Christian , Le Fort Patrick
Published: November 2011

This paper reviews the petrogenesis of Himalayan leucogranites (HHγ) on the basis of field, petrological and geochemical data collected over the last fifteen years. HHγ are intruded at the top of the 2 to 8km-thick High Himalayan Crystallines (HHC). These are metamorphosed (Ky to Sill) and present much evidence of partial melting. During the MCT thrusting, the already metamorphosed HHC were thrust on top of the weakly metamorphosed Midland Formations, inducing the main phase of Himalayan metamorphism. The genesis of HHγ and North Himalaya leucogranites (NHγ) associates thrusting along the MCT, propagation of inverted metamorphism, liberation of large quantities of fluid in the Midlands, and partial melting of the HHC.

The restricted compositions of the granites are close to minimum melt compositions; variations in the alkali ratio probably relate to the variable amount of B, F and H2O. The HHγ were issued from the migmatitic zone around 700°C and 800 MPa., and still emplaced some 10 to 15 km below the surface. This syn- to late-tectonic emplacement of the leucogranites lasted for more than 10 Ma according to isotopic ages (25 to 14 Ma).

O, Rb–Sr, Nd–Sm and Pb isotope studies corroborate the unambiguous filiation between the HHC and the leucogranites in central Nepal. They also imply that the plutons are generated as numerous poorly mixed batches of magma produced preferentially in specific zones of the source rock. δD values may be explained by infiltration of water from the Midlands in the melting zone, and/or by water degassing during crystallisation. The positive covariations between Sr-, Nd- and O-isotope ratios relate to the variations in the original sediment composition of the source gneisses. Whereas trace element characteristics often date back to the anatectic process, limited magmatic differentiation is recorded by the biotite. These granites are typical crustal products, keeping track of some of the pre-Himalayan evolution together with that of their own origin.
The fluid dynamics of crustal melting by injection of basaltic sills
Authors: Huppert Herbert E. , Stephen R. , Sparks J.
Published: November 2011

When basaltic magma is emplaced into continental crust, melting and generation of granitic magma can occur. We present experimental and theoretical investigations of the fluid dynamical and heat transfer processes at the roof and floor of a basaltic sill in which the wall rocks melt. At the floor, relatively low density crustal melt rises and mixes into the overlying magma, which would form hybrid andesitic magma. Below the roof the low-density melt forms a stable layer with negligible mixing between it and the underlying hotter, denser magma. Our calculations applied to basaltic sills in hot crust predict that sills from 10-1500 m thick require only 2-200 years to solidify, during which time large volumes of overlying layers of convecting silicic magma are formed. These time scales are very short compared with the lifetimes of large silicic magma systems of around 106 years, and also with the time scale of 107 years for thermal relaxation of the continental crust. An important feature of the process is that crystallisation and melting occur simultaneously, though in different spots of the source region. The granitic magmas formed are thus a mixture of igneous phenocrysts and lesser amounts of restite crystals. Several features of either plutonic or volcanic silicic systems can be explained without requiring large, high-level, long-lived magma chambers.
Relationships between silicic plutonism and volcanism: geochemical evidence
Authors: Macdonald R. , Smith R. L.
Published: November 2011

Field associations (voluminous ash flow deposits, rhyolitic stocks and dykes, ring complexes), evidence of repeated influxes of mafic magma, and thermal constraints indicate that many high-level silicic plutons (magma chambers) acted as open systems for considerable parts of their history. The long thermal lifetime, as well as other evidence from the volcanic record, suggests that some such systems reached a quasi-steady state in which magma input was balanced by magma output for times longer than those required for crystallisation. Reconstruction of the evolution of large, long-lived caldera-forming systems, such as that of the Jemez Mountains, New Mexico, indicates that many chambers have lost a highly fractionated silicic cap, in some cases cyclically. Crystallised plutons may contain no obvious record of this evolutionary phase.

Geochemical data from silicic ash flow deposits can be used to reconstruct the volcanic stage of pluton development. Many silicic systems, especially of alkaline affinity, apparently pass from a stage in which melt evolution is dominated by crystal-liquid processes to one in which other processes may also contribute to differentiation. Apparently, the transition is most readily achieved in volatile-rich, alkaline silicic systems emplaced in complex, ancient sialic crust of the cratons. Once established, the preservation of highly fractionated caps on magma chambers requires a balance between thermal input and cooling-induced crystallisation. If heat enters the system too quickly, the cap may get stirred into the dominant magma volume by convection. If heat input is too slow, the magma body will crystallise inward from the margins, and the plutonic-consolidation stage will begin.
Compositional zonation and cumulus processes in the Mount Mazama magma chamber, Crater Lake, Oregon
Authors: Druitt Timothy H. , Bacon Charles R.
Published: November 2011

The 6845 ± 50 BP climactic eruption of Mount Mazama discharged 47 ± 9 km3of vertically zoned calc-alkaline magma, affording a virtually complete section through the chamber. Evidence for two andesitic parents with different trace-element (particularly Sr) and water contents is preserved in the ejecta. Prior to eruption, a dominant volume of rhyodacite was underlain successively by high-Sr andesite, high-Sr crystal mushes, and low-Sr crystal mushes. Intergranular liquids in the high-Sr magmas were probably richer in water than those in the low-Sr magmas. Thermal continuity throughout the ejecta favours eruption from a single, zoned reservoir. Insight into chamber development is given by preclimactic rhyodacitic lavas and tephra erupted between about 30,000 BP and the climactic eruption. The oldest of these lavas, contaminated derivatives of low-Sr magma, contain crystal-poor magmatic inclusions of low-Sr andesite; the youngest has inclusions of high-Sr andesite and, like rhyodacitic pumice in the climactic ejecta, is hybrid magma containing an admixed high-Sr component. A model for steady-state growth of the chamber is inferred whereby repeated recharge, first by low-Sr then high-Sr andesite (± basalt), builds up a cumulate succession, while derivative liquid fractionates convectively, segregates, and mixes with an incrementally growing silicic volume. The magma chamber at Mount Mazama may provide insight into the evolution of some granitoid plutons.
Late Ordovician–early Silurian destruction of the Iapetus Ocean: Newfoundland, British Isles and Scandinavia—a discussion
Authors: Pickering Kevin T. , Bassett Michael G. , Siveter David J.
Published: November 2011

The available data from Newfoundland, the British Isles and Scandinavia suggest that by late Ordovician–early Silurian times the ocean separating Laurentia from Eastern Avalonia and Baltica had partly closed with the consumption of intervening oceanic crust. Marine seaways, however, persisted until the middle or late Silurian. Phases of crustal transtension and transpression, predominantly under a major sinistral shear couple, occurred throughout the Silurian and early Devonian until the remnant Iapetus Ocean was completely destroyed. The most appropriate Recent plate tectonic models for Silurian sedimentation between Eastern Avalonia and Laurentia are probably the deep-marine foreland basins between Timor and the northern Australian margin, or between Taiwan and mainland China.
Geology, geochemistry and geochronology of a taconic batholith, southwestern Newfoundland
Authors: Dunning G. R. , Wilton D. H. C. , Herd R. K.
Published: November 2011

Foliated to massive hornblende and biotite-bearing tonalite, trondhjemite and granodiorite comprise a terrane of batholithic dimensions in southwestern to central Newfoundland. These rocks intrude and include Ordovician ophiolite fragments and metasedimentary rocks of Fleur de Lys type, and are cut by a suite of Silurian gabbro-diorite and norite and Siluro-Devonian (?) granite intrusions.

A U/Pb (zircon, sphene) age of 456 ± 3 Ma (2σ) and a K/Ar (hornblende) age of 455 ± 14 Ma (previously reported) for a representative least-deformed tonalite of the Southwest Brook Complex indicate that it crystallised and cooled in Caradoc time. A less precise U/Pb (zircon) age of 428 ± 41 Ma (2σ) is measured for tonalitic Cape Ray Granite in southern Newfoundland. On discrimination diagrams which use Rb, Nb and Y contents to infer tectonic setting, these rocks fall in the field of volcanic arc granites. The occurrence of zircon cores with average ages of 1430 + 18/–17 and 1541 ± 173 Ma (2σ) also indicate that the magmas formed in part by partial melting of Proterozoic crust, or sediments derived from such crust. It is suggested that the tonalitic magmas were generated during the Taconic Orogeny in an arc: continent collision zone at the ancient margin of eastern North America.

Tonalitic rocks in western Newfoundland broadly correlative in age and chemistry with the batholith include the Burlington Granodiorite and Hungry Mountain Complex, as well as allochthonous slices of foliated tonalite emplaced over Ordovician platform carbonates W of Grand Lake.
Milankovitch and albedo forcing of the tropical monsoons: a comparison of geological evidence and numerical simulations for 9000 yBP
Authors: Street-Perrott F. A. , Mitchell J. F. B. , Marchand D. S. , Brunner J. S.
Published: November 2011

Lake-level and palaeoecological evidence from Africa, Arabia and southern Asia for 9000 yBP suggests an intensification and increased poleward penetration of the northern monsoons. The vegetation belts shifted north by 4–6° latitude on the south side of the Sahara. In contrast, the monsoon over southern Africa was weaker than today. Calculations based on the new palaeogeographical map of Mali by Petit-Maireet al.(1988) indicated that the areaaveraged surface albedo decreased by 0·10–0·14 in the zone 16–24°N and that total annual precipitation increased by 150–320 mm north of the inland delta of the Niger (20–24° 15′N). Experiments with atmospheric general-circulation models suggest that this asymmetrical pattern of anomalies in the strength of the tropical monsoons can be explained in broad terms by the different orbital configuration of the Earth at 9000 yBP. Here, we describe a hitherto unpublished sensitivity experiment with the low-resolution (5° × 7·5°) version of the U.K. Meteorological Office 11-layer model, in which the albedo over Africa and Arabia between 15 and 30°N was reduced by between 0·04 and 0·06 to simulate the increase in vegetation cover at 9000 yBP. The results indicate that the surface-albedo change provides a significant positive feedback enhancing the direct climatic effects of Milankovitch forcing in the tropics.
Petrochemistry of late Palaeozoic alkali lamprophyre dykes from N Scotland
Authors: Baxter A. N.
Published: November 2011

The lower Carboniferous–late Permian dyke swarms of the Scottish Highlands and Islands comprise a mild-strongly alkaline basic series of dolerites, camptonites and monchiquites. Differentiation within the suite was largely controlled by olivine + clinopyroxene fractionation. Major and trace element data indicate that dolerites and camptonites chemically overlap, their mineralogical contrasts resulting from differential loss of an H2O, CO2-rich fluid phase during ascent. By contrast most monchiquites have high Mg-values and are relatively primitive compositions, some being near-primary magmas which have risen rapidly from mantle levels with little chemical modification.

HREE-buffered incompatible element profiles imply a garnet–lherzolite source, which must underlie the lithospheric mantle region represented by spinel lherzolite xenoliths found in some monchiquites.C. 0·5–2·0% partial melting can account for the gross incompatible element variation in the suite, but relative fluctuations in K, Ba, Rb, Sr, P and Zr imply chemical heterogeneity controlled either by refractory mantle accessory phases or by modification of magmas during ascent through variably metasomatised lithospheric mantle.
Geodynamic significance of post-Variscan intrusive and extrusive potassic magmatism in SW England
Authors: Leat P. T. , Thompson R. N. , Morrison M. A. , Hendry G. L. , Trayhorn S. C.
Published: November 2011

Post-Variscan magmatism in SW England involved the synchronous emplacement of basaltic and potassic lavas, minette dykes and the Cornubian granite batholith at c. 290 Ma. The basaltic and potassic rocks have high contents of Ni and Cr, which suggest that both are not excessively fractionated. The basaltic lavas are moderately enriched in LREE and LIL elements relative to HREE, whereas the chemically-varied potassic lavas are more strongly enriched in LREE and LIL elements, with notable depletions in Nb, Ta and Ti relative to LREE. These features are consistent with the view that these rocks are subduction-related. Possibly the potassic rocks were derived from an ultimate source in lithosphere subducted or downthrust during the Variscan orogeny. The source of the basaltic rocks was probably in the asthenosphere. The minette dykes are chemically similar to the potassic lavas, suggesting that they are genetically related. Most dykes occur in a zone up to 25 km wide around the margin of the granite batholith, in a “shadow-zone” relationship. The granite batholith (c. 48,000 km3) is moderately enriched in Th and HFS elements, but is strongly enriched in Rb. Rb-Th relationships indicate an origin for the granite by fractionation from potassic magma in addition to melting of crust.
The evolution of ecological tolerance in prokaryotes
Authors: Knoll Andrew H. , Bauld John
Published: November 2011

The ecological ranges of Archaeobacteria and Eubacteria are constrained by a requirement for liquid water and the physico-chemical stability limits of biomolecules, but within this broad envelope, prokaryotes have evolved adaptations that permit them to tolerate a remarkable spectrum of habitats. Laboratory experiments indicate that prokaryotes can adapt rapidly to novel environmental conditions, yet geological studies suggest early diversification and long-term stasis within the prokaryotic kingdoms. These apparently contradictory perspectives can be reconciled by understanding that, in general, rates and patterns of prokaryotic evolution reflect the developmental history of the Earth's surface environments. Our understanding of modern microbial ecology provides a lens through which our accumulating knowledge of physiology, molecular phylogeny and the Earth's history can be integrated and focussed on the phenomenon of prokaryotic evolution.
What, if anything, is a brackish-water fauna?
Authors: Barnes R. S. K.
Published: November 2011

The nature of the fauna of brackish-water environments is reviewed. It is concluded that: (a) a specific brackish-water macrofauna does not exist; (b) in salinities of >c. 5-8‰ the fauna is one that also occurs in soft sediments under fully marine conditions when circumstances (possibly the absence of competing species) permit; (c) in salinities of <c. 5‰ the fauna is essentially a freshwater one; and (d) inability to cope physiologically with brackish water is not a factor of major importance in limiting species diversity in these habitats, except in the vicinity of 5‰ salinity. Caution is therefore advised in assigning brackish status to past environments on the basis of their preserved fauna.
Physiological constraints on living and fossil brachiopods
Authors: Curry Gordon B. , Ansell A. D. , James M. , Peck L.
Published: November 2011

Ash-free-dry-weight determinations for a representative range of living brachiopod genera have revealed that a consistently high proportion of total organic mass is contained within the shell, partly as the organic matrix for biomineralisation and partly as minute extensions of the mantle tissues (caeca) housed within hollow endopunctae permeating the shell. On average 40% to 50% of the total organic mass of both articulate and inarticulate brachiopods is situated within the shell. This is true even for a rhynchonellid brachiopod which does not possess endopunctae, but which has a more dense protein matrix in its shell. The effectively hidden constituent of brachiopod tissue mass which is included in this component has often been overlooked, and as a result total metabolic tissue mass has been underestimated. This throws into question some previous interpretations of brachiopod respiratory and metabolic data.

The oxygen consumption rates of several living brachiopods have been measured, and when respiring tissue in caeca in the shell is taken into consideration, it is clear that brachiopod metabolic rates are low when compared with other marine invertebrates (e.g. between 10% and 50% of the oxygen uptake of comparable gastropods and bivalve molluscs held in similar conditions). This low rate cannot be attributed to a slower pumping rate by the brachiopod lophophore, as has been suggested, because the rate of water movement is comparable to that across the bivalve gill.

Nitrogen excretion rates have also been measured for a few living brachiopods, allowing a comparison with rates of oxygen consumption and providing an indication of the metabolic substrates used. These data on oxygen: nitrogen ratios suggest that one Antarctic brachiopod utilises exclusively protein as a metabolic substrate, while a temperate latitude species uses mainly protein during winter but lipids and carbohydrates during summer months. Histological observations, particularly of Terebratulina retusa from temperate waters, show that a specialised tissue layer in the brachiopod outer mantle epithelium proximal to the shell may be the site of storage of the protein that is metabolised during winter, and of carbohydrate mobilised during gonadal development in summer. The caeca have also been suggested as sites of storage of metabolites, and the possible relationships between these areas of mantle are discussed. It seems that the ability to store nutrients in the mantle, combined with flexibility of substrate utilisation and an inherently low metabolic rate, have been important factors in brachiopod evolution.
Applying the ecosystem services concept to poverty alleviation: the need to disaggregate human well-being
Authors: DAW TIM , BROWN KATRINA , ROSENDO SERGIO , POMEROY ROBERT
Published: November 2011

The concept of ecosystem services (ES), the benefits humans derive from ecosystems, is increasingly applied to environmental conservation, human well-being and poverty alleviation, and to inform the development of interventions. Payments for ecosystem services (PES) implicitly recognize the unequal distribution of the costs and benefits of maintaining ES, through monetary compensation from ‘winners’ to ‘losers’. Some research into PES has examined how such schemes affect poverty, while other literature addresses trade-offs between different ES. However, much evolving ES literature adopts an aggregated perspective of humans and their well-being, which can disregard critical issues for poverty alleviation. This paper identifies four issues with examples from coastal ES in developing countries. First, different groups derive well-being benefits from different ES, creating winners and losers as ES, change. Second, dynamic mechanisms of access determine who can benefit. Third, individuals' contexts and needs determine how ES contribute to well-being. Fourth, aggregated analyses may neglect crucial poverty alleviation mechanisms such as cash-based livelihoods. To inform the development of ES interventions that contribute to poverty alleviation, disaggregated analysis is needed that focuses on who derives which benefits from ecosystems, and how such benefits contribute to the well-being of the poor. These issues present challenges in data availability and selection of how and at which scales to disaggregate. Disaggregation can be applied spatially, but should also include social groupings, such as gender, age and ethnicity, and is most important where inequality is greatest. Existing tools, such as stakeholder analysis and equity weights, can improve the relevance of ES research to poverty alleviation.
Evaluating the environmental impact of payments for ecosystem services in Coatepec (Mexico) using remote sensing and on-site interviews
Authors: SCULLION JASON , THOMAS CRAIG W. , VOGT KRISTINA A. , PÉREZ-MAQUEO OCTAVIO , LOGSDON MILES G.
Published: November 2011

Over the last decade, hundreds of payments for ecosystem services (PES) programmes have been initiated around the world, but evidence of their environmental benefits remains limited. In this study, two PES programmes operating in the municipality of Coatepec (Mexico) were evaluated to assess their effectiveness in protecting the region's endangered upland forests. Landsat satellite data were analysed to assess changes in forest cover before and after programme implementation using a difference-in-differences estimator. Additionally, surveys and interviews were conducted with local residents and a subset of PES programme participants to evaluate the programmes’ social and environmental impacts, particularly the effect of the programmes on landowner behaviour. The remote-sensing data show that deforestation was substantially lower on properties receiving PES payments compared to properties not enrolled in the programmes, but the programmes did not prevent the net loss of forests within Coatepec. Moreover, the on-site interviews suggest that the payments may have had little impact on deforestation rates, and that other factors contributed to the conservation of forests in PES properties. These findings suggest that risk-targeted payments, robust monitoring and enforcement programmes, and additional conservation initiatives should be included in all PES schemes to ensure environmental effectiveness.
From racecourse to People's Park and People's Square: historical transformation and symbolic significance
Authors: YUEZHI XIONG
Published: November 2011

Horse racing ended in Shanghai in 1945, but the public continued for a long time to make its opinion heard on the prohibition of horse racing and on the changing function of the racecourse. In 1951, the dust settled, and the racecourse became People's Park and People's Square. This article describes the ever changing symbolic significance of the racecourse that has played out against a backdrop of changing racecourse functions and varying intellectual currents. Initially, it was a relatively simple place of leisure. It later became a gambling arena where people were cheated of their money and sometimes murdered, a place where Chinese suffered discrimination, and a stage on which imperialism flaunted its military might. It had, in short, become a diabolic symbol of a multitude of evils. The call to change the racecourse merged powerfully with the struggle to oppose imperialism, regain the settlement and struggle towards civilization and democracy. In spite of changes in the ruling party and the replacement of one regime by another, a remarkable ideological and intellectual continuity persisted from the 1930s to the 1950s.
Fleeing from firestorms: government, cities, native place associations and refugees in the Anti-Japanese War of Resistance
Authors: LINCOLN TOBY
Published: November 2011

This article explores the refugee experiences of three communities in Shanghai during the Japanese invasion of China in 1937. Social and political organizations worked together in different ways to send people safely back to different parts of China. I argue that this shows how migrant identities were trans-local and that urban identity in the first half of the twentieth century in China was never wholly confined within one city. Rather, networks of individuals and institutions worked together to handle the crisis caused by one of the most devastating invasions of World War II.
Assessing Therapeutic Competence in Cognitive Therapy for Social Phobia: Psychometric Properties of the Cognitive Therapy Competence Scale for Social Phobia (CTCS-SP)
Authors: von Consbruch Katrin , Clark David M. , Stangier Ulrich
Published: November 2011

Background: There has been considerable acknowledgement in treatment outcome research that, although the assessment of treatment integrity is essential in many respects, it requires great effort as well as resources and is therefore often neglected. Aims: In order to fill this gap, the Cognitive Therapy Competence Scale for Social Phobia (CTCS-SP) was developed, based on the Cognitive Therapy Scale, to measure therapist competence in delivering cognitive therapy for social phobia. The aim of the present study was to investigate interrater reliability, internal consistency and retest reliability of the scale. Method: Raters evaluated therapist competence from 161 videotaped sessions (98 patients) selected from 234 cognitive treatments within a multi-centre study. Results: Interrater-reliability was found to be high for the overall score (ICC = .81) and moderate for individual items (ICC = .62–.92). Internal consistency and retest reliability were also found to be high (Cronbach's alpha = .89; (ICCretest = .86). Conclusions: The results indicate that the CTCS-SP is highly reliable. As even individual items yield satisfactory reliability, the scale can be used in various fields of research, including the measurement of changes in skill acquisition and the impact of competence on outcome criteria.
Remote laser‐induced breakdown spectroscopy (LIBS) for lunar exploration
Authors: Lasue J. , Wiens R. C. , Clegg S. M. , Vaniman D. T. , Joy K. H. , Humphries S. , Mezzacappa A. , Melikechi N. , McInroy R. E. , Bender S.
Published: November 2011

Laser‐induced breakdown spectroscopy (LIBS) is an active analytical technique that makes use of a laser pulse to analyze materials of interest at a distance by creating a plasma, which emits photons at characteristic emission line wavelengths. We validate the technique for planetary exploration under vacuum conditions. We review the capability and advantages of the LIBS technique for lunar regolith analysis at 1.5 m distance from a lunar rover, and we characterize its potential for the detection of resources for future exploration, such as the determination of regolith water content. The limits of detection determined for the major elements (typically <1 wt %) help to determine regolith parent material such as feldspathic highland rocks, rocks from the ancient magmatic high magnesian suite (Mg‐suite), Fe‐rich mare basalts or potassium, rare earth element, and phosphorus‐rich (KREEP‐rich) samples. Compositional parameters commonly used to classify lunar regoliths such as TiO2, Al2O3, and K2O abundances are readily determined by LIBS. Certain elements support regolith analysis: For example, Ba and Zr can be used to confirm KREEP‐like composition, while quantifying the Ni and Co content can be used to infer the amount of meteoritic material. Finally, it is shown that the ice content of lunar soil produces strong H emissions with the LIBS techniques at the 25 wt % H2O level, while measurements on altered basalts give a limit of detection of about 1 wt % for H2O content. This demonstrates that the 5.6 wt % water content detected by the recent LCROSS experiment should be easily detectable and quantifiable by LIBS analysis.
A simple 1‐D radiative‐convective atmospheric model designed for integration into coupled models of magma ocean planets
Authors: Marcq E.
Published: November 2011

In order to understand the early history of telluric interiors and atmospheres during the ocean magma stage, a coupled interior‐atmosphere‐escape model is being developed. This paper describes the atmospheric part and its first preliminary results. A unidimensional, radiative‐convective, H2O‐CO2 atmosphere is modeled following a vertical T(z) profile similar to Kasting (1988) and Abe and Matsui (1988). Opacities in the thermal IR are then computed using a k‐correlated code (KSPECTRUM), tabulated continuum opacities for H2O‐H2O and CO2‐CO2 absorption, and water or sulphuric acid clouds in the moist convective zone (whenever present). The first results show the existence of two regimes depending on the relative value of the surface temperature Ts compared to a threshold temperature Tc depending on the total gaseous inventory. For Ts < Tc, efficient blanketing results in a cool upper atmosphere, a cloud cover, and a long lifetime for the underneath magma ocean with a net thermal IR flux between 200 and 280 Wm−2. For Ts > Tc, the blanketing is not efficient enough to prevent large radiative heat loss to space through a hot, cloudless atmosphere. Our current calculations may underestimate the thermal flux in the case of hot surfaces with little gaseous content in the atmosphere.
One‐Year Results of the Think Health! Study of Weight Management in Primary Care Practices
Authors: Kumanyika Shiriki K. , Fassbender Jennifer E. , Sarwer David B. , Phipps Etienne , Allison Kelly C. , Localio Russell , Morales Knashawn H. , Wesby Lisa , Harralson Tina , Kessler Ronni , Tan‐Torres Susan , Han Xiaoyan , Tsai Adam G. , Wadden Thomas A.
Published: November 2011

The Think Health! study evaluated a behavioral weight loss program adapted from the Diabetes Prevention Program (DPP) lifestyle intervention to assist primary care providers (PCPs) and auxiliary staff acting as lifestyle coaches (LCs) in offering weight loss counseling to their patients. In a randomized trial conducted at five clinical sites, study participants were randomly assigned in a 1:1 ratio within each site to either “Basic Plus” (n= 137), which offered PCP counseling every 4 months plus monthly LC visits during the first year of treatment, or “Basic” (n= 124), which offered only PCP counseling every 4 months. Participants were primarily (84%) female, 65% African American, 16% Hispanic American, and 19% white. In the 72% of participants in each treatment group with a 12‐month weight measurement, mean (95% CI) 1‐year weight changes (kg) were −1.61 (−2.68, −0.53) in Basic Plus and −0.62 (−1.45, 0.20) in Basic (difference: 0.98 (−0.36, 2.33);P= 0.15). Results were similar in model‐based estimates using all available weight data for randomized participants, adjusting for potential confounders. More Basic Plus (22.5%) than Basic (10.2%) participants lost ≥5% of their baseline weight (P= 0.022). In a descriptive, nonrandomized analysis that also considered incomplete visit attendance, mean weight change was −3.3 kg in Basic Plus participants who attended ≥5 LC visits vs. + 0.53 kg in those attending <5 LC visits. We conclude that the Basic Plus approach of moderate‐intensity counseling by PCPs and their staff can facilitate modest weight loss, with clinically significant weight loss in high program attenders.
The Regulatory Status of Gum Arabic
Authors: Phillips G.O.
Published: November 2011

The traditional approval for the use of gum arabic in food has been as a “food additive”. In Europe this has been subject to the ever-evolving Directives of the European Parliament and Council on Food Additives. Internationally, it is the Compendium of Food Additive Specification issued by the FAO/WHO which sets the criteria and these do not of necessity adopt the same definitions. Over the years there have been anomalies and changes due in the main to the action of various pressure groups championing their individual points of view.
Sustainable Development in Africa - Research and Development Openings
Authors: Jaouen I. , Berepion B. , Bernadi E. , Malhiac C. , Grisel M.
Published: November 2011

Alland & Robert is a French company established in 1884 that has been dedicated to natural gums from the very start. With three locations including two production plants, this company has an annual global production of 8,000 tons with a total capacity of 11,000 tons. Alland & Robert is involved in gum acacia collection in Africa mainly in Senegal, Mali and Chad and is committed to developing a relationship of confidence with different local companies situated in these countries.
Gum Collection and Collectors’ Choice of Selling Outlet in Senegal
Authors: Mujawamariya G. , D'Haese M. , Burger K.
Published: November 2011

Gum arabic, the main product of Acacia senegal, is used in various industries (food, pharmaceutical, painting, etc). It is traded in local markets for processing and consumption within producing countries but mainly for the purpose of exportation as a non-timber forest product. Senegal is among the small gum producing countries in Africa, Sudan being the world's largest producer. In the late 1950's, Senegal's exports accounted for more than 10 percent of the world exports.
Rheological Properties of Gum Arabic Solution: the Effect of Arabinogalactan Protein Complex (AGP)
Authors: Li X. , Zhang H. , Fang Y. , Al-Assaf S. , Phillips G.O. , Nishinari K.
Published: November 2011

Gum arabic solution is generally regarded as a Newtonian liquid with an anomalous low viscosity. However, recent research on the rheological properties of gum arabic in water has shown that it is not simply Newtonian. In this work, rheological properties of gum arabic solutions were investigated, with emphasis on its non-Newtonian behaviour of shear thinning and thixotropy, and interpreted based on molecular association in the solution. It was found that the arabinogalactan protein complex (AGP) in gum arabic might be the main source of molecular association though it only represents about 10% of the total gum. The occurrence of AGP micelles endowed the gum arabic solution with non-Newtonian behaviour of shear thinning and thixotropy. This fact was evidenced by using single-walled carbon nanotubes (SWNTs) to trap AGP. The non-Newtonian behavior of gum arabic solution vanished after AGP was removed from the solution.
Effect of AGP on Emulsifying Stability of Gum Arabic
Authors: Nishino M. , Katayama T. , Sakata M. , Al-Assaf S. , Phillips G.O.
Published: November 2011

Gum arabic (Acacia senegal) is an important natural oil-in-water emulsifier, which is widely used in the food industry. However, emulsification performance of natural gum arabic greatly varies depending on origin, production area, tree age, the weather and changes in arabinogalactan protein (AGP) content during storage. The correlation between AGP components and emulsifying stability has been studied in detail using natural gum arabic. Molecular weight and AGP content were analysed using GPC-MALLS (Gel permeation chromatography – multi-angle laser light scattering) and emulsifying stability was evaluated by measuring the particle size of test emulsions after accelerated storage. AGP content of natural gum arabic varies greatly. Gum arabic with a higher AGP content has a higher emulsifying stability, whereas gum arabic with a lower AGP content has a lower emulsifying stability. It is very important for emulsion users to have access to a supply of high performance natural gum arabic with a higher and consistent AGP content.
Interactions of Bacteria and Fungi at the Surface
Authors: Dworniczek* E. , Franiczek R. , Nawrot U. , Gościniak G.
Published: November 2011

The increased life span of humans and the dynamic development of Biomaterials' industry have led to widespread use of implants in modern medicine. Microorganisms, mostly opportunistic flora,are able to adapt perfectly to the changing environment of their host. Bacteria, once regarded as non-pathogenic, successfully bind to artificial surfaces resulting in diseases that are difficult to treat. The Chapter discusses the process of microbial adhesion to the surfaces. It provides the brief description of the most important infections of humans, which result from the microbial colonization of implanted biomaterials. This adhesion is characterized in the context of physicochemical and biological interactions between microorganism and the surface. We describe the effects of environmental factors and the contribution of bacterial/fungal cell structures on microbial adhesion. Finally, the Chapter presents the most important aspects of interactions between bacteria and charged surfaces.