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Windy Craggy is an approximately 300 Mt Cu-Co-Au volcanogenic massive sulphide (VMS) deposit in northwestern British Columbia, Canada. The Windy Craggy deposit is hosted by the Middle Tats Volcanics (MTV), a Late Triassic volcano-sedimentary sequence of intercalated mafic pillowed to massive volcanic flows and sills and calcareous argillite that are part of the Alexander terrane. The host footwall and hangingwall flows and sills are predominantly alkalic basalts (Nb/Y > 0.70). MTV alkali basalts at Windy Craggy are enriched in light rare earth elements (LREEs) >100X chondrite compared to chondrite, have steep REE patterns [(La/Yb)cn = 7.1–25.4], and generally lack the Ta and Nb depletions relative to primitive mantle (e.g. [Nb/Th]pm = 0.68–1.94) characteristic of arc environments, although most have [Nb/La]pm < 1. By contrast, volcanic rocks away from the deposit (and regionally; Lower Tats Volcanics, LTV) as well as late dikes that cross-cut all lithologies including metamorphic and deformational fabrics are sub-alkalic tholeiitic to calc-alkaline basalts and basaltic andesites that are less enriched in the LREEs (10–100X chondrite), have less steep REE patterns [(La/Yb)cn = 0.41–10.6], and show well-developed Ta and Nb depletions (arc signatures; [Nb/Th]pm = 0.20–0.79), consistent with formation in an oceanic arc environment. The co-occurrence of tholeiitic/calc-alkaline arc rocks with alkalic rocks indicates that the LTV (former) and MTV (latter) formed from melts that were influenced to varying degrees by subducted oceanic crust, and likely formed within a back-arc basin setting formed on a rifted oceanic arc. There is no geochemical or isotopic evidence for major involvement of continental crust. The LTV basalts likely were produced by progressive depletion in the source by partial melting of mantle overlying the subducting oceanic crust. The presence of the MTV alkalic Windy Craggy rocks overlying the LTV is consistent with the presence of a slab-window, perhaps related to subduction of a spreading centre, which allowed more enriched magmas to reach the surface with only minimal interaction with subduction-modified mantle. The presence of this slab-window might have provided the mechanism for the generation of anomalously high heat flow close to the seafloor, which initiated and sustained vigorous, long-lived hydrothermal activity necessary for the precipitation of large accumulations of massive sulphide. To our knowledge, this is the first example of a large VMS deposit associated with a slab-window. [ABSTRACT FROM PUBLISHER]

Tectonics and climate are the major extrinsic upstream controls on both the external and internal architectures of fluvial channels. While the role of tectonics has been well-documented, the role of climate has received less attention. Because both tectonics and climate can produce similar stratigraphic architectures, the ability to recognize and differentiate these has major ramifications for the interpretation of fluvial stratigraphy. The Pennsylvanian to Permian succession of the Maritimes Basin complex on Cape Breton Island is ca 5 km thick, and is composed of predominantly non-marine strata deposited within a series of depocentres characterized by different subsidence regimes. Basins in the west are transtensional depocentres characterized by episodic fault movement. In contrast, basins in the east were formed during prolonged periods of passive thermal subsidence. The stratigraphy is composed of four second-order sequences (A to D), each 5 to 10 Myr in duration. These sequences are composed of amalgamated fluvial channel deposits that fine upwards into extensive mud-dominated floodplain deposits with isolated fluvial channel bodies. A spectrum of fluvial styles is recorded within the study area including perennial, perennial/intermittent and ephemeral. Four stratigraphic intervals (E1 to E4) are recognized in which the deposits of strongly seasonal perennial/intermittent fluvial deposits are predominant. These intervals, 2 to 6 Myr in duration, are correlated across the study area between basins with differing tectonic regimes and do not correlate with a particular position in second-order sequences. This suggests that climate exerted the dominant influence on the formation of these intervals and can be differentiated from tectonic imprints. While the tectonic regime of a particular basin exerted a fundamental control on the external architecture, a coherent record of climate change is recognized in the internal architecture of fluvial units. This study demonstrates that tectonic and climatic controls can be recognized and differentiated in vertical successions by evaluating the changes in fluvial architecture. [ABSTRACT FROM AUTHOR]

This paper explores the exhibition spaces of the Mattress Factory Art Museum (MF) in Pittsburgh, Pennsylvania through my personal and theoretical interpretations. Included are an introduction to the museum and its history and a narrative of my first visit. I examine the MF's use of space and my sensorial experience of it, applying Michel de Certeau and Henri Lefebvre's spatial theories. Further, I view the MF as one large installation including its connected exhibition spaces and its archi-texture (Lefebvre, 1974/1991), which is comprised of its buildings' multiple historical functions and its immediate urban neighborhood surroundings. The MF's spatial practices in which its artists use room-size installations with unusual forms, sounds, and lighting effects in their work immerse visitors in a multi-sensorial, interactive, often exploratory experience in which they "engage" the artworks by their perceptions and responses, and their cultural background and experience. [ABSTRACT FROM AUTHOR]

The Erebus Glacier Tongue, a small floating glacier in southern McMurdo Sound, is one of the best-studied ice tongues in Antarctica. Despite this, its calving on the 27 February 2013 (UTC) was around 10 yr earlier than previously predicted. The calving was likely a result of ocean currents and the absence of fast ice. The subsequent trajectory of the newly created iceberg supports previous descriptions of the surface ocean circulation in southern McMurdo Sound. [ABSTRACT FROM AUTHOR]

India and China are two Asian emerging economies, the unprecedented growth of which have led many to argue that in the face of slowdown in growth of the North these emerging economies will act as the new growth drivers for the South. However, not much empirical evidence is available to support this argument. This article estimates the growth linkages between the developing Asia and the two Asian emerging economies in terms of co-integration and causation in their growth rates. Both short-term and long-term relationships are tested between growth of China and India with growth of the developing countries of Asia for the period 1970-2009. The issue of whether these countries can provide market for the South is also examined. The results show that whereas China has acted as a growth driver for the developing Asia, no empirical evidence of this is found for India.L'Inde et la Chine sont deux pays asiatiques émergents dont la croissance sans précédent laisse penser à beaucoup que, dans le contexte du ralentissement au Nord, ces économies émergentes agiront comme de nouveaux moteurs de croissance pour le Sud. Il existe cependant peu de preuves empiriques à l'appui de cette thèse. Cet article propose une estimation des liens de croissance entre l'Asie en développement et les deux économies asiatiques émergentes, en termes de co-intégration et de causalité entre leurs taux de croissance. Nous testons les liens, à court et à long terme, entre la croissance de la Chine et de l'Inde et celle des pays d'Asie en développement sur la période 1970-2009. La question de savoir si ces pays peuvent constituer un marché pour le Sud est également examinée. Les résultats montrent que la Chine joue effectivement le rôle de moteur de croissance pour l'Asie en développement, mais qu'il n'existe aucune preuve empirique que l'Inde joue le même rôle. [ABSTRACT FROM AUTHOR]

Over the past two decades, scholarship on call centres has grown with contributions from a range of disciplines including management science, urban studies, organisation studies and sociology. One aspect of call centres that has received only limited attention is their location or economic geography. This article contributes to the growing body of scholarship on call centres by investigating locational issues in the case of the developing economy of South Africa. The study highlights the critical importance for call centre location of access to labour, labour costs, public transport and availability of suitable premises. Current government incentives have little significance on location, a factor which underlies the strong concentration of call centres in South Africa's major cities, in particular Johannesburg and Cape Town. [ABSTRACT FROM AUTHOR]

The article discusses the gendered aspects of the Vietnam War, with a particular focus on survivors of the war living in the Thinh Tri commune in Northern Vietnam. According to the author, the trauma experienced by such communities in wartime is shaped both by existing sociocultural understandings of gender and the state's strategic use of gender roles. It is suggested that survivors' collective memory constitutes a counternarrative to Vietnamese national commemoration discourse surrounding the war. Details related to the corporeality of war and philosopher Giorgio Agamben's concept of bare life are presented. Other topics include sacrifice, suffering, and ethnography.

Background: Salmonids are popular sport fishes, and as such have been subjected to widespread stocking throughout western North America. Historically, stocking was done with little regard for genetic variation among populations and has resulted in genetic mixing among species and subspecies in many areas, thus putting the genetic integrity of native salmonid populations at risk and creating a need to assess the genetic constitution of native salmonid populations. Cutthroat trout is a salmonid species with pronounced geographic structure (there are 10 extant subspecies) and a recent history of hybridization with introduced rainbow trout in many populations. Genetic admixture has also occurred among cutthroat trout subspecies in areas where introductions have brought two or more subspecies into contact. Consequently, management agencies have increased their efforts to evaluate the genetic composition of cutthroat trout populations to identify populations that remain uncompromised and manage them accordingly, but additional genetic markers are needed to do so effectively. Here we used genome reduction, MID-barcoding, and 454-pyrosequencing to discover single nucleotide polymorphisms that differentiate cutthroat trout subspecies and can be used as a rapid, cost-effective method to characterize the genetic composition of cutthroat trout populations. Results: Thirty cutthroat and six rainbow trout individuals were subjected to genome reduction and next-generation sequencing. A total of 1,499,670 reads averaging 379 base pairs in length were generated by 454- pyrosequencing, resulting in 569,060,077 total base pairs sequenced. A total of 43,558 putative SNPs were identified, and of those, 125 SNP primers were developed that successfully amplified 96 cutthroat trout and rainbow trout individuals. These SNP loci were able to differentiate most cutthroat trout subspecies using distance methods and Structure analyses. Conclusions: Genomic and bioinformatic protocols were successfully implemented to identify 125 nuclear SNPs that are capable of differentiating most subspecies of cutthroat trout from one another. The ability to use this suite of SNPs to identify individuals of unknown genetic background to subspecies can be a valuable tool for management agencies in their efforts to evaluate the genetic structure of cutthroat trout populations prior to constructing and implementing conservation plans. [ABSTRACT FROM AUTHOR]

This paper analyzes the possibilities and challenges of Fair Trade certification as a movement seeking to improve the well-being of small-scale coffee growers and coffee laborers in the global South. Six months of fieldwork was conducted in 2005–2006 to study the roles of a wide range of farmers, laborers, cooperative administrators, and export companies in Fair Trade coffee production and trade in Nicaragua. The results of our evaluation of the ability of Fair Trade to meet its objectives indicate that Fair Trade’s opportunities to provide a significant price premium for participating farmers largely depend on world coffee prices in mainstream markets. While Fair Trade has promoted premiums for social development for participating producers and strengthened the institutional capacities of the cooperatives involved, its ability to enhance significantly the working conditions of hired coffee laborers remains limited. [ABSTRACT FROM AUTHOR]

Studies have demonstrated the impact of battlefield outcomes on financial markets in the case of the US Civil War and other existential struggles. But many wars (such as Vietnam and Iraq) have been wars of choice. In these wars, military victories have not necessarily led to peace. Investigation of the market impact of battlefield and diplomatic events in the context of a war of choice offers the opportunity to distinguish the market's interest in peace as distinct from victory; and, the usefulness of identifying events from the study of history as an adjunct to the empirical identification of break-points. [ABSTRACT FROM AUTHOR]

We estimated demographic parameters and harvest risks for polar bears ( Ursus maritimus) inhabiting the Gulf of Boothia, Nunavut, from 1976 to 2000. We computed survival and abundance from capture–recapture and recovery data (630 marks) using a Burnham joint live–dead model implemented in program MARK. Annual mean total survival (including harvest) was 0.889 ± 0.179 (&xmacr;± 1 SE) for cubs, 0.883 ± 0.087 for subadults (ages 1–4), 0.919 ± 0.044 for adult females, and 0.917 ± 0.041 for adult males. Abundance in the last 3 yr of study was 1,592 ± 361 bears. Mean size of newborn litters was 1.648 ± 0.098 cubs. By age 7, 0.97 ± 0.30 of available females were producing litters. Harvest averaged 38.4 ± 4.2 bears/year in the last 5 yr of study; however, the 2002–2007 kill averaged 56.4 bears/yr. We used a harvested Population Viability Analysis (PVA) to examine impacts of increasing rates of harvest. We estimated the current population growth rate, λ H, to be 1.025 ± 0.032. Although this suggests the population is growing, progressive environmental changes may require more frequent population inventory studies to maintain the same levels of harvest risk. [ABSTRACT FROM AUTHOR]

Reindeer husbandry represents a major land use in the Barents region, and has been predicted to be adversely affected by climate change. This paper considers the likely response of reindeer husbandry to changes both in climate and in socio-economic circumstances in the four countries of the Barents region from 1990 to 2080. Key natural factors include vegetation distribution, and a range of meteorological variables including temperature, wind, snow cover and freezing of rivers. The potential impact of these factors is evaluated quantitatively using the tolerable windows method, the results of which indicate a general but spatially non-uniform decline in the suitability of the region for reindeer husbandry. Relevant socio-economic factors include regional patterns of politics, management and knowledge. A focus on herders' own perceptions of environmental change and flexibility of response, derived particularly from study sites in Russia, suggests that models of vulnerability to climate change should be tempered by paying greater attention to changes in socio-economic factors. When compared with the potential effect of changing these socioeconomic factors, the vulnerability of reindeer husbandry to projected climate change appears to be comparatively small. [ABSTRACT FROM AUTHOR]

Although facies models of braided, meandering and anastomosing rivers have provided the cornerstones of fluvial sedimentology for several decades, the depositional processes and external controls on sheetflow fluvial systems remain poorly understood. Sheetflow fluvial systems represent a volumetrically significant part of the non-marine sedimentary record and documented here are the lithofacies, depositional processes and possible roles of rapid subsidence and arid climate in generating a sheetflow-dominated fluvial system in the Cenozoic hinterland of the central Andes. A 6500 m thick succession comprising the Late Eocene–Oligocene Potoco Formation is exposed continuously for >100 km along the eastern limb of the Corque syncline in the high Altiplano plateau of Bolivia. Fluvial sandstone and mudstone units were deposited over an extensive region (>10 000 km2) with remarkably few incised channels or stacked-channel complexes. The Potoco succession provides an exceptional example of rapid production of accommodation sustained over a prolonged period of time in a non-marine setting (>0·45 mm year−1 for 14 Myr). The lower ≈4000 m of the succession coarsens upward and consists of fine-grained to medium-grained sandstone, mudstone and gypsum deposits with palaeocurrent indicators demonstrating eastward transport. The upper 2500 m also coarsens upward, but contains mostly fine-grained to medium-grained sandstone that exhibits westward palaeoflow. Three facies associations were identified from the Potoco Formation and are interpreted to represent different depositional environments in a sheetflow-dominated system. (i) Playa lake deposits confined to the lower 750 m are composed of interbedded gypsum, gypsiferous mudstone and sandstone. (ii) Floodplain deposits occur throughout the succession and include laterally extensive (>200 m) laminated to massive mudstone and horizontally stratified and ripple cross-stratified sandstone. Pedogenic alteration and root casts are common. (iii) Poorly confined channel and unconfined sheet sandstone deposits include laterally continuous beds (50 to >200 m) that are defined primarily by horizontally stratified and ripple cross-stratified sandstone encased in mudstone-rich floodplain deposits. The ubiquitous thin-sheet geometry and spatial distribution of individual facies within channel sandstone and floodplain deposits suggest that confined to unconfined, episodic (flash) flood events were the primary mode of deposition. The laterally extensive deposition and possible distributary nature of this sheetflow-dominated system are attributed to fluvial fan conditions in an arid to semi-arid, possibly seasonal, environment. High rates of sediment accumulation and tectonic subsidence during early Andean orogenesis may have favoured the development and long-term maintenance of a sheetflow system rather than a braided, meandering or anastomosing fluvial style. It is suggested here that rapidly produced accommodation space and a relatively arid, seasonal climate are critical conditions promoting the generation of sheetflow-dominated fluvial systems. [ABSTRACT FROM AUTHOR]

In this article, I trace the efforts of a development team working to promote a Canadian approach to natural resources management in the Russian North. These development workers used two communication strategies related to time and history to render Canadian knowledge mobile and applicable to a new location: (1) imagining today's Russian North as equivalent to the Canadian northern past and (2) reframing and idealising the Canadian past and present to make the governance export less discursively ‘messy’ for an outside audience. The relative failure of these communicative strategies points to the need for richer dialogue in efforts to move knowledge cross-culturally. [ABSTRACT FROM AUTHOR]

This study highlights regional variation in the composition of iron-smelting slag produced in England prior to the medieval period and attempts to link slag composition to the type of ore smelted. For many sites, the slag compositions were consistent with the use of limonite ore, but there is evidence that siderite ore was smelted at sites in Sussex in the late Iron Age/Romano-British periods. A compositional comparison of smelting slags and slag inclusions in Iron Age currency bars, using data from Hedges and Salter (1979 ), illustrates the potential of smelting slag compositional data in provenance studies of early iron objects. [ABSTRACT FROM AUTHOR]

The Arctic climate is changing. Permafrost is warming, hydrological processes are changing and biological and social systems are also evolving in response to these changing conditions. Knowing how the structure and function of arctic terrestrial ecosystems are responding to recent and persistent climate change is paramount to understanding the future state of the Earth system and how humans will need to adapt. Our holistic review presents a broad array of evidence that illustrates convincingly; the Arctic is undergoing a system-wide response to an altered climatic state. New extreme and seasonal surface climatic conditions are being experienced, a range of biophysical states and processes influenced by the threshold and phase change of freezing point are being altered, hydrological and biogeochemical cycles are shifting, and more regularly human sub-systems are being affected. Importantly, the patterns, magnitude and mechanisms of change have sometimes been unpredictable or difficult to isolate due to compounding factors. In almost every discipline represented, we show how the biocomplexity of the Arctic system has highlighted and challenged a paucity of integrated scientific knowledge, the lack of sustained observational and experimental time series, and the technical and logistic constraints of researching the Arctic environment. This study supports ongoing efforts to strengthen the interdisciplinarity of arctic system science and improve the coupling of large scale experimental manipulation with sustained time series observations by incorporating and integrating novel technologies, remote sensing and modeling. [ABSTRACT FROM AUTHOR]

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Abstract: A general mathematical model for population dispersal featuring long range taxis is presented and exemplified by the dispersal episode of the Africanized honey bees (Apis mellifera adansonii) throughout the American Continent. The mathematical model is a discrete-time and nonlocal model represented by an integrodifference recursion. A new taxis concept is defined and introduced into the mathematical model by an appropriate modification of the redistribution kernel. The model is capable of predicting the natural barrier for the expansion of the Africanized honey bees in the southern part of the Continent due to low winter temperatures. It also describes a sensitive expansion velocity with respect to the quality of resources, which can explain the AHB’s astounding spread rate, by using two different kinds of population dynamics strategies, one for a resourceful environment and the other for poor regions. [Copyright &y& Elsevier]

The article presents discovery of carp, Cyprinus carpio, in the already stressed fishery of Lake Naivasha in Kenya. The lake originally contained endemic fish species. To enhance the fish production, a new fish species was introduced into Lake Naivasha. This fish species, Carp is capable to exploit benthic chironomid larvae and oligochaetes. The feeding method of carp puts bottom material into suspension. Carp could be beneficial in consuming juvenile crayfish populations and aquatic macrophytes. The species is tolerant of a degraded aquatic environment and capable of spawning.

We analyzed long-term records of ice thickness on the Piscataquis River in central Maine and air temperature in Maine to determine whether there were temporal trends that were associated with climate warming. The trend in ice thickness was compared and correlated with regional time series of winter air temperature, heating degree days (HDD), date of river ice-out, seasonal center-of-volume date (SCVD) (date on which half of the stream runoff volume during the period 1 Jan. to 31 May has occurred), water temperature, and lake ice-out date. All of these variables except lake ice-out date showed significant temporal trends during the 20th century. Average ice thickness around 28 February decreased by about 23 cm from 1912 to 2001. Over the period 1900 to 1999, winter air temperature increased by 1.7 °C and HDD decreased by about 7.5%. Final ice-out date on the Piscataquis River occurred earlier (advanced), by 0.21 days yr−1 over the period 1931 to 2002, and the SCVD advanced by 0.11 days yr−1 over the period 1903 to 2001. Ice thickness was significantly correlated (P-value <0.01) with winter air temperature, HDD, river ice-out, and SCVD. These systematic temporal trends in multiple hydrologic indicator variables indicate a coherent response to climate forcing. [ABSTRACT FROM AUTHOR]

Population estimates are rarely constructed for ecological regions. The recent establishment of a Desert Knowledge Cooperative Research Centre (CRC) generates a need for such estimates. This paper obliges by presenting Indigenous and total population projections for the Australian desert to 2016. The desert is found to be a region of relatively low population growth in national terms, contrary to the experience of many other parts of non-metropolitan Australia where population decline is prevalent. Also noted is the markedly different growth observed for the Indigenous and non-Indigenous components of the desert population, with the former projected to increase much more rapidly over time. It is likely that virtually all of the increase in the desert population over the next 15 years will arise from natural increase among Indigenous peoples. As a consequence, the Indigenous share of the regional population is projected to rise from 20 per cent in 2001 to 24 per cent by 2016, with attendant consequences for social and economic policy. [ABSTRACT FROM AUTHOR]

Levels of drug resistance of Plasmodium falciparum strains against antimalarials have increased in Laos. In several studies, chloroquine (CQ) resistance has been associated with point mutations in the Pfcrt and pfmdr genes, and sulphadoxine/pyrimethamine (S/P) resistance with point mutations in the genes of dihydrofolate reductase (DHFR) and dihydropteroate synthetase (DHPS). We combined a study of these molecular markers with an in vivo antimalarial drug sensitivity study in Attapeu province in the south of Lao PDR. We treated 100 patients with either CQ, S/P or a combination of both. In the CQ group, Pfcrt mutations showed a very high sensitivity (100%) but a low specificity (12.5%) to predict resistance. The combination of mutations in the Pfcrt and pfmdr genes was highly specific and had a positive predictive value of 100%. Mutations in the DHPS gene showed a high correlation with the development of resistance. The prevalence of mutations in the DHFR gene, especially codon 108 Asn, was predictive with high sensitivity (100%) but low specificity. Isolates derived from patients treated with a combination of both drugs showed a high correlation between the mutation in codon 437 of DHPS gene and in vivo-resistance (odds ratio 16.00, CI). The study provides evidence for the existence of antimalarial drug resistance in the south of Lao PDR, and offers a molecular method to predict resistance. [ABSTRACT FROM AUTHOR]

Focuses on the criticism of strategies for their inability to resolve economic development dilemmas in Africa. Requirement for developing countries to appease capital demands; Experience of economic marginalisation in sub-Saharan Africa.

This article features the transcription, translation, and analysis of two primordial titles, written in the Mixtec and Nahuatl languages, and a large map. Two indigenous communities in the Valley of Oaxaca attempted to lay claim to disputed territory by presenting these competing "titles," ostensibly written in the 1520s, to Spanish authorities in the 1690s. The titles present each community's account of the Spanish Conquest of Oaxaca and subsequent colonial events. We consider how the documents shed light on Mixtec and Nahua ethnic identity and historical memory in the Valley of Oaxaca in the late colonial period. [ABSTRACT FROM AUTHOR]

Point mutations in the dihydrofolate reductase (DHFR) and dihydropteroate synthase (DHPS) genes of Plasmodium falciparum can lead to an increasing resistance of P. falciparum to pyrimethamine/sulphadoxine. We examined the prevalence of these mutations in 36 samples from Colombia. Analysed by polymerase chain reaction (PCR) for infection with P. falciparum, 25 (69%) tested positive. These positive isolates were tested further for point mutations in the genes of DHFR (codons 16, 51, 59, 108 and 164) and DHPS (codons 436, 437, 540, 581 and 613) by nested PCR and following mutation-specific restriction enzyme digestion. Gene mutations occurred in both the DHFR and DHPS gene of the Colombian isolates, suggesting that resistance to antifolate drugs exists or may develop soon in Colombia. [ABSTRACT FROM AUTHOR]

Discusses the structural and chemical composition of copper and tin ingots from the Late Bronze Age shipwreck of Kas/Uluburun, found at the southern coast of Anatolia. Production of ingots from raw copper smelted in a furnace and remelted in a crucible; Poor quality of the copper ingots; Heavy corrosion of tin ingots; Presence of trace elements in the metal.

The permafrost regions currently occupy about one quarter of the Earth's land area.Climate-change scenarios indicate that global warming will be amplified in the polarregions, and could lead to a large reduction in the geographic extent of permafrost.Development of natural resources, transportation networks, and human infrastructurein the high northern latitudes has been extensive during the second half of the twentiethcentury. In areas underlain by ice-rich permafrost, infrastructure could be damagedseverely by thaw-induced settlement of the ground surface accompanying climatechange. Permafrost near the current southern margin of its extent is degrading, andthis process may involve a northward shift in the southern boundary of permafrostby hundreds of kilometers throughout much of northern North America and Eurasia.A long-term increase in summer temperatures in the high northern latitudes couldalso result in significant increases in the thickness of the seasonally thawed layerabove permafrost, with negative impacts on human infrastructure located on ice-richterrain. Experiments involving general circulation model scenarios of global climatechange, a mathematical solution for the thickness of the active layer, and digitalrepresentations of permafrost distribution and ice content indicates potential forsevere disruption of human infrastructure in the permafrost regions in response toanthropogenic climate change. A series of hazard zonation maps depicts generalizedpatterns of susceptibility to thaw subsidence. Areas of greatest hazard potential includecoastlines on the Arctic Ocean and parts of Alaska, Canada, and Siberia in whichsubstantial development has occurred in recent decades. [ABSTRACT FROM AUTHOR]

This paper offers a critique of politically dominant Eurocentric notions of culture and nature in Australia. In particular, it interrogates Eurocentric concepts of animals, wildlife and management, and seeks to unsettle these concepts by considering some of the diverse ways in which indigenous people in Australia know country, animals and wilderness. Using the metaphor of Eurocentric ontology in a hall of mirrors, the paper argues that Eurocentric claims of universalism for naturalised discourses that assume the adequacy of a nature–culture binary form a very fragile circular argument. Self-justifying the imposition and assertion of Eurocentric concepts and practices is a mechanistic reflection of the particular terms of reference set by Eurocentric knowledges and a denial of multiple ways of knowing. The dangers this presents are illustrated by examining how concepts and practices underlying wildlife management have self-justified (continuing) colonising processes in Australia. Finally, the paper attempts to open up spaces that address these dangers. Situated engagement is introduced as an approach which could shatter the hall of mirrors—by clearly embodying and emplacing all thought and action, universalised boundaries can be recognised and breached and new possibilities imagined and realised. [ABSTRACT FROM AUTHOR]

The increasing resistance of Plasmodium falciparum in the treatment of uncomplicated malaria with pyrimethamine/sulphadoxine has been associated in several studies with the occurrence of point mutations in the genes of dihydrofolate reductase (DHFR) and dihydropteroate synthetase (DHPS). In this study, the prevalence of these mutations was examined in samples from south-east Mauritania, where atypically strong rainfalls in 1998 and 1999 led to a severe outbreak of falciparum malaria. We analysed 386 samples by polymerase chain reaction (PCR) for infection with P. falciparum, of which 162 (41.97%) were positive. These isolates were examined for point mutations in the genes of DHFR (codons 16, 51, 59, 108 and 164) and DHPS (codons 436, 437, 540, 581 and 613) by nested PCR and subsequent mutation-specific restriction enzyme digest. We found a low overall prevalence of DHFR gene mutations (up to 18.6% of isolates), but a high overall prevalence of DHPS gene mutations (up to 49.1% of isolates). Thus, emerging resistance to antifolate drugs may be expected to develop soon in the investigated area. This study demonstrates the utility of simple, relatively rapid and inexpensive molecular methods and their application in surveillance programmes. Testing for prevalence of point mutations conferring antifolate resistance might help to identify the developing of drug resistance at a very early stage. [ABSTRACT FROM AUTHOR]

In an illustration of a model evaluation methodology, a multivariate reduced form model is developed to evaluate the sensitivity of a land surface model to changes in atmospheric forcing. The reduced form model is constructed in terms of a set of ten integrative response metrics, including the timing of spring snow melt, sensible and latent heat fluxes in summer, and soil temperature. The responses are evaluated as a function of a selected set of six atmospheric forcing perturbations which are varied simultaneously, and hence each may be thought of as a six-dimensional response surface. The sensitivities of the land surface model are interdependent and in some cases illustrate a physically plausible feedback process. The important predictors of land surface response in a changing climate are the atmospheric temperature and downwelling longwave radiation. Scenarios characterized by warming and drying produce a large relative response compared to warm, moist scenarios. The insensitivity of the model to increases in precipitation and atmospheric humidity is expected to change in applications to coupled models, since these parameters are also strongly implicated, through the representation of clouds, in the simulation of both longwave and shortwave radiation. [ABSTRACT FROM AUTHOR]

Physiological traits related to water transport were studied in Rhizophora mangle (red mangrove) growing in coastal and estuarine sites in Hawaii. The magnitude of xylem pressure potential (Px), the vulnerability of xylem to cavitation, the frequency of embolized vessels in situ, and the capacity of R. mangle to repair embolized vessels were evaluated with conventional and recently developed techniques. The osmotic potential of the interstitial soil water (πsw) surrounding the roots of R. mangle was c. –2.6±5.52×10–3 and –0.4±6.13×10–3 MPa in the coastal and estuarine sites, respectively. Midday covered (non-transpiring) leaf water potentials (ΨL) determined with a pressure chamber were 0.6–0.8 MPa more positive than those of exposed, freely-transpiring leaves, and osmotic potential of the xylem sap (πx) ranged from –0.1 to –0.3 MPa. Consequently, estimated midday values of Px (calculated by subtracting πx from covered ΨL) were about 1 MPa more positive than ΨL determined on freely transpiring leaves. The differences in ΨL between covered and transpiring leaves were linearly related to the transpiration rates. The slope of this relationship was steeper for the coastal site, suggesting that the hydraulic resistance was larger in leaves of coastal R. mangle plants. This was confirmed by both hydraulic conductivity measurements on stem segments and high-pressure flowmeter studies made on excised leafy twigs. Based on two independent criteria, loss of hydraulic conductivity and proportions of gas- and liquid-filled vessels in cryo-scanning electron microscope (cryo-SEM) images, the xylem of R. mangle plants growing at the estuarine site was found to be more vulnerable to cavitation than that of plants growing at the coastal site. However, the cryo-SEM analyses suggested that cavitation occurred more readily in intact plants than in excised branches that were air-dried in the laboratory. Cryo-SEM analyses also revealed that, in both sites, the proportion of gas-filled vessels was 20–30% greater at midday than at dawn or during the late afternoon. Refilling of cavitated vessels thus occurred during the late afternoon when considerable tension was present in neighboring vessels. These results and results from pressure-volume relationships suggest that R. mangle adjusts hydraulic properties of the water-transport system, as well as the leaf osmotic potential, in concert with the environmental growing conditions. [ABSTRACT FROM AUTHOR]

The Upper Devonian to Lower Carboniferous Skrinkle Sandstones of the Pembroke Peninsula are predominantly continental deposits from the post-Caledonian synrift succession at the southern margin of the Upper Palaeozoic Welsh Landmass. The lower part of the Sandstones record deposition in the 30 × 10 km Tenby–Angle fault block, from which a 6- to 68-m-thick interval is described and interpreted as a lacustrine deposit succeeded by a high-energy sandy braidplain succession. The lacustrine deposit is dominated by red mudstones and ripple cross-laminated sandstones. Interbedded quartzose sandstones form a coarsening-upward sequence from the red mudstones in the basin centre, suggesting a deltaic origin, and a smooth-fronted braidplain delta model is proposed. The sequence introduces the braidplain succession, composed of groups of horizontal/low-angle laminated and trough cross-bedded sandstones. These are compared with recent ephemeral stream and sheetflood sediments and their characteristics used to depict a system of mutually erosive sheetflood and channel bodies, the latter produced during the rising and falling stages of flood events, which alternate to produce a thick multistorey sandstone. Palaeocurrent data indicate an axial drainage system from the north-west, running parallel to the main faults of the area. This is supported by the maturity and sandy nature of the sediments. Basin closure towards the south and the postulated Bristol Channel Landmass is inferred. [ABSTRACT FROM AUTHOR]

How is the concept of sustainable development represented in major U.S. newspapers? Are academic and activists' critiques part of the media message? Using a systematic qualitative analysis, the author examines the themes and sources of newspaper articles from 1987 to 1997. Sustainable development is presented almost exclusively within an economic growth paradigm that assumes that economic growth, technology, and northern expertise are the most effective way to achieve development. The activists and academics that are used as sources do not present alternatives to the dominant development discourse. Instead, the few alternatives that are presented are by the authors of commentaries who are not identified with environmental activist groups. [ABSTRACT FROM AUTHOR]

The Gabčíkovo Water Project (GWP), a major construction of damming and canalizing on the upper part of the middle Danube was completed and put into operation in October 1992. It destroyed most of the 230 km² of wetlands. Two-thirds of the wetlands are becoming dry, discontinuous or severely changed which will ultimately destroy the original ecosystem and lead to a decline in biological diversity. Based upon detailed knowledge of the limnology and fish biology of this section of the Danube River the effects of the GWP were predicted as early as 1964. All the recent post-construction impact studies of the GWP report few negative effects and so the planners and builders defend the project. It is difficult to believe that all sides in the current GWP legal controversy have overlooked the most important point. Any effects immediately after construction are purely transitory. A large body of published empirical and theoretical information clearly shows that the mostly negative effects of such large water projects become apparent only several years or decades after construction. The value of the destroyed wetland and river floodplain is at least US $520 million per year, and clearly incriminates the VV (Vodohospodárska výstavba) of fraudulent representation of `benefits'. The enormous flood of devious publications glorifying the work of the VV in recent years should be interpreted as a cover up for the bad conscience of the builders. The International Court of Justice in the Hague delivered its judgement on the GWP case on 25 September 1997. There were no winners in this case as both Slovakia and Hungary were said to have acted inappropriately: it was illegal for Hungary to stop its part on the project according to the treaty of 1977, and Slovakia had no right to put Gabčíkovo into operation unilaterally. As the Court dealt little with the social, environmental and economic aspects of the GWP, the true losers became the inland delta of the Danube, the last large wetland of Europe, and the local inhabitants. [ABSTRACT FROM AUTHOR]