Local Conditions (local + condition)

Distribution by Scientific Domains
Distribution within Life Sciences

Selected Abstracts

Recent trends from Canadian permafrost thermal monitoring network sites

Sharon L. Smith
Abstract The Geological Survey of Canada (GSC), in collaboration with other government partners, has been developing and maintaining a network of active-layer and permafrost thermal monitoring sites which contribute to the Canadian Permafrost Monitoring Network and the Global Terrestrial Network for Permafrost. Recent results from the thermal monitoring sites maintained by the GSC and other federal government agencies are presented. These results indicate that the response of permafrost temperature to recent climate change and variability varies across the Canadian permafrost region. Warming of shallow permafrost temperatures of between 0.3 and 0.6°C per decade has occurred since the mid- to late 1980s in the central and northern Mackenzie region in response to a general increase in air temperature. No significant warming (less than 0.1°C per decade) of permafrost is observed in the southern Mackenzie valley. Warming of shallow permafrost of between 1.0 and 4.0°C per decade is also observed in the eastern and high Arctic, but this mainly occurred in the late 1990s. These trends in permafrost temperature are consistent with trends in air temperature observed since the 1970s. Local conditions however, influence the response of the permafrost thermal regime to these changes in air temperature. Copyright © 2005 John Wiley & Sons, Ltd. [source]

Integration of environmental and host-derived signals with quorum sensing during plant,microbe interactions

J. A. Newton
Summary Many plant-associated microbes use secreted autoinducer molecules, including N -acylhomoserine lactones (AHLs), to regulate diverse behaviours in association with their population density (quorum sensing). Often, these responses are affected by environmental conditions, including the presence of other AHL-producing bacterial species. In addition, plant-derived metabolites, including products that arise as a direct result of the bacterial infection, may profoundly influence AHL-regulated behaviours. These plant products can interact directly and indirectly with the quorum-sensing network and can profoundly affect the quorum-sensing behaviour. Local conditions on a microscopic scale may affect signal molecule longevity, stability and accumulation, and this could be used to give information in addition to cell density. Furthermore, in many Gram-negative bacteria, AHL signalling is subservient to an additional two-component signalling system dependent upon homologues of GacS and GacA. The signal(s) to which GacS responds are not known, but recent research suggests that a self-produced ligand may be being detected. This review will focus on two well-studied examples of AHL-regulated plant-associated behaviour, Erwinia carotovora and Agrobacterium tumefaciens, to illustrate the complexity of such signalling networks. [source]

Introduction Strategies Put to the Test: Local Adaptation versus Heterosis

exogamia; introducciones multi-fuente; introducciones uni-fuente; Succisa pratensis Abstract:,Plant biodiversity has declined seriously because of both habitat deterioration and habitat fragmentation. As a result, many species have been forced into small, fragmented, and isolated populations and are believed to suffer from higher extinction risks. Genetic reinforcement and the establishment of new populations are now widely used to prevent extinction. However, the genetic background of transplants may seriously affect the long-term success of these populations because increased genetic variation may reduce the risk of inbreeding or lead to better performance by restored heterozygosity levels (heterosis). Introduced transplants, however, may be poorly adapted to the new local conditions. We tested the initial success of alternative introduction strategies. We evaluated the potential for inbreeding, heterosis, and/or local adaptation after introduction of artificial populations of Succisa pratensis. We introduced individuals from local and distant artificial populations that were created from either small or large populations. We created the artificial populations with the same census population size but varying effective population sizes by adjusting the relatedness of individuals. We analyzed the demographic consequences of inbreeding, heterosis, and/or local adaptation of these artificial populations. Reduced performance after selfing was manifested by a reduction in seed production, seed weight, germination, and flowering percentage. Seed production, seed weight, flowering percentage, and number of flowerheads were negatively affected by small population size. Local adaptation increased biomass and flowering percentage for local individuals. Seed weight and seed production exhibited significant heterosis. Our results demonstrate that threatened populations can benefit from introduction and genetic reinforcement of individuals from related populations. Significant differences among the artificial populations for several measured performance components suggest that introduction or reinforcement is best achieved through material from a local population or, when unavailable, from several large populations. Resumen:,La biodiversidad de plantas ha declinado seriamente tanto por el deterioro como la fragmentación de hábitats. Como resultado, muchas especies han sido relegadas a poblaciones pequeñas, fragmentadas y aisladas cuyos riesgos de extinción se piensa que son mayores. El reforzamiento genético y el establecimiento de poblaciones nuevas se utilizan ampliamente en la actualidad para prevenir la extinción. Sin embargo, los antecedentes genéticos de transplantes pueden afectar seriamente el éxito de estas poblaciones a largo plazo debido a que el incremento en la variación genética puede reducir el riesgo de endogamia o puede conducir a un mejor rendimiento por lograr niveles de heterocigosidad restaurados (heterosis). No obstante, los trasplantes introducidos pueden adaptarse deficientemente a las nuevas condiciones locales. Probamos el éxito inicial de estrategias de introducción alternativas. Evaluamos el potencial de endogamia, heterosis y/o adaptación local después de la introducción de poblaciones artificiales de Succisa pratensis. Introdujimos individuos de poblaciones locales y de poblaciones artificiales distantes que fueron creadas a partir de poblaciones tanto pequeñas como grandes. Las poblaciones artificiales fueron creadas con el mismo tamaño poblacional censal pero variaron en tamaños poblacionales efectivos al ajustar la parentela de los individuos. Analizamos las consecuencias demográficas de la endogamia, heterosis y/o adaptación local de estas poblaciones artificiales. Después de la autofecundación se manifestó una reducción en el rendimiento por reducción en la producción y peso de semillas y en el porcentaje de germinación y floración. La producción y peso de semillas, el porcentaje de floración y el número de botones florales fueron afectados negativamente por el tamaño poblacional pequeño. La adaptación local incrementó la biomasa y el porcentaje de floración en individuos locales. El peso y producción de semillas mostró heterosis significativa. Nuestros resultados demuestran que las poblaciones amenazadas pueden beneficiarse de la introducción y del reforzamiento genético de individuos de poblaciones emparentadas. Las diferencias significativas entre las poblaciones artificiales en varios de los componentes de rendimiento medidos sugiere que la introducción o reforzamiento se logra mejor con material de una población local o, cuando no disponible, con material de varias poblaciones grandes. [source]

The Costly Business of Trust

Mark Cosson
This article provides a framework for analysing trust-based projects which can be used as a diagnostic tool to design more effective policy interventions, particularly addressing the problem of meeting users' needs for which many microfinance schemes have come under criticism. Two microfinance projects in Mexico are used to illustrate how a system of trust is built, the role of trust-brokers, and the policy of subsidising trust-building projects. The aim is to provide a tool capable of identifying crucial actors in trust systems and the nature of the linkages between them, so that trust can be effectively operationalised to improve projects' effectiveness and suitability to local conditions. [source]


EVOLUTION, Issue 7 2007
Mathieu Perret
The geographical pattern of speciation and the relationship between floral variation and species ranges were investigated in the tribe Sinningieae (Gesneriaceae), which is found mainly in the Atlantic forests of Brazil. Geographical distribution data recorded on a grid system of 0.5 × 0.5 degree intervals and a near-complete species-level phylogenetic tree of Sinningieae inferred from a simultaneous analysis of seven DNA regions were used to address the role of geographical isolation in speciation. Geographical range overlaps between sister lineages were measured across all nodes in the phylogenetic tree and analyzed in relation to relative ages estimated from branch lengths. Although there are several cases of species sympatry in Sinningieae, patterns of sympatry between sister taxa support the predominance of allopatric speciation. The pattern of sympatry between sister taxa is consistent with range shifts following allopatric speciation, except in one clade, in which the overlapping distribution of recent sister species indicates speciation within a restricted geographical area and involving changes in pollinators and habitats. The relationship between floral divergence and regional sympatry was also examined by analyzing floral contrasts, phenological overlap, and the degree of sympatry between sister clades. Morphological contrast between flowers is not increased in sympatry and phenological divergence is more apparent between allopatric clades than between sympatric clades. Therefore, our results failed to indicate a tendency for sympatric taxa to minimize morphological and phenological overlap (geographic exclusion and/or character displacement hypotheses). Instead, they point toward adaptation in phenology to local conditions and buildup of sympatries at random with respect to flower morphology. Additional studies at a lower geographical scale are needed to identify truely coexisting species and the components of their reproductive isolation. [source]

Evolutionary ecology, sexual conflict, and behavioral differentiation among baboon populations

Peter Henzi
Abstract A central assumption of baboon socio-ecological models is that all populations have the same capacity to react to different environments. The burden of our argument is that this assumption needs to be reconsidered. Data suggest not only that hamadryas, but chacma as well, differ in interesting ways from the stock baboon model that has been derived, in the main, from earlier work on anubis and cynocephalus. Although environmental factors are behind these differences, much of their influence is a consequence of their effect on restricted ancestral populations, where selection for appropriate responses to the social challenges set by local conditions now constrains the nature of individual responses to contemporary environments. Available genetic evidence suggess a southern African origin for Papio at a time when climatic conditions were certainly no better than they are now and when temperatures, if nothing else, were probably lower. In light of this, a reconstruction of how climate has structured the sexual conflict between males and female charcma, which itself hinges on infanticide, can help explain not only the East African pattern, but also how the apparently anomalous hamadryas pattern has been derived. [source]

Eco-phenotypic growth in juvenile smooth marron, Cherax cainii (Decapoda: Parastacidae)

Abstract, The smooth marron, Cherax cainii Austin, now occurs in regions of Western Australia that are warmer and drier than those of the natural distribution. Animals sourced along a south to north geographical axis decrease in body mass per unit length. Juveniles reared from gravid females sourced from four sites along this axis were raised in common laboratory conditions for 14 weeks. No differences between sites were observed in body mass, standardised for length, indicating that in situ differences are a phenotypic response to local conditions. [source]

The relative importance of local conditions and regional processes in structuring aquatic plant communities

Summary 1. The structure of biological communities reflects the influence of both local environmental conditions and processes such as dispersal that create patterns in species' distribution across a region. 2. We extend explicit tests of the relative importance of local environmental conditions and regional spatial processes to aquatic plants, a group traditionally thought to be little limited by dispersal. We used partial canonical correspondence analysis and partial Mantel tests to analyse data from 98 lakes and ponds across Connecticut (northeastern United States). 3. We found that aquatic plant community structure reflects the influence of local conditions (pH, conductivity, water clarity, lake area, maximum depth) as well as regional processes. 4. Only 27% of variation in a presence/absence matrix was explained by environmental conditions and spatial processes such as dispersal. Of the total explained, 45% was related to environmental conditions and 40% to spatial processes. 5. Jaccard similarity declined with Euclidean distance between lakes, even after accounting for the increasing difference in environmental conditions, suggesting that dispersal limitation may influence community composition in the region. 6. The distribution of distances among lakes where species occurred was associated with dispersal-related functional traits, providing additional evidence that dispersal ability varies among species in ways that affect community composition. 7. Although environmental and spatial variables explained a significant amount of variation in community structure, a substantial amount of stochasticity also affects these communities, probably associated with unpredictable colonisation and persistence of the plants. [source]

Transfer or adapt business practices internationally?

Some answers from Southeast Asia
International organizations have long been torn between transferring their existing practices into new locations or adapting to local conditions. A major miscalculation can have extremely negative consequences for companies as they expand internationally. An examination of business practices in the Theravada Buddhist countries of Southeast Asia illustrates how breaking down business practices into their strategic, tactical, and operational levels may provide a useful guide for setting up initial operations in a foreign environment. It is proposed that strategic principles can be transferred but strategic practices should adapt to local conditions; tactical-level business practices will generally need to adapt to the local environment, while it is likely that best practices at the operational level can be transferred across international borders with little need to adapt to local conditions. © 2010 Wiley Periodicals, Inc. [source]

Southern African social movements at the 2007 Nairobi World Social Forum

Abstract How relevant is the anti-globalization movement to the ideas and activities of social movements seeking to achieve economic justice and greater democratic accountability in southern Africa? Case study research in four southern African countries (Zimbabwe, Zambia, Malawi and Swaziland) indicates that, while aspects of the anti-globalization approach resonate with civil society and social movement actors (for example, an emphasis on mass participation and the internationalization of campaigning), the global social justice movement frequently displays the characteristics of globalization. These include: unaccountable decision-making; profound (yet largely unacknowledged) inequality of access to resources; and an imposed and uniform organizational form that fails to consider local conditions. The World Social Forum (WSF) held in Nairobi in January 2007 provided many southern African social movement actors with their first opportunity to participate in the global manifestation of the anti-globalization movement. The authors interviewed social movement activists across southern Africa before and during the Nairobi WSF about their experiences of the anti-globalization movement and the Social Forum. An assessment of the effectiveness of this participation leads to the conclusion that the WSF is severely limited in its capacity to provide an effective forum for these actors to express their grievances and aspirations. However, hosting national social forums, their precise form adapted to reflect widely varied conditions in southern African states that are affected by globalization in diverse ways, appears to provide an important new form of mobilization that draws on particular elements of anti-globalization praxis. [source]

Development Zones, Foreign Investment, and Global City Formation in Shanghai*

ABSTRACT The rapid economic ascent of China and the increasing integration of the world economy in the past two decades have made metropolises in China such as Shanghai and Beijing emerging global cities. Foreign investment is a central force underlying the emergence and transformation of the Chinese metropolises into global cities. This is especially true in Shanghai, which has experienced massive infusion of foreign investment. Varied forms of foreign investment or development zones have been created to promote foreign investment inflows, yet remain under-studied. This paper analyzes structure, performance, and underlying factors of development zones in Shanghai, and discusses the implications for global city-formation; it unfolds the variations among development zones, and illustrates the significant role of the state and local conditions. As the literature on global cities dwells primarily on the experiences of advanced economies, this paper further contributes to a better understanding of the dynamics of emerging global cities in the developing world. [source]

Quantifying diffuse pathways for overland flow between the roads and streams of the mountain ash forests of central Victoria Australia

Patrick N. J. Lane
Abstract Limiting connectivity between road runoff sources and stream networks is crucial for preservation of water quality in forested environments. Where flow is non-eroding, the length of hillslope available to accommodate volumes of discharged water is the key to restricting connectivity. Hairsine et al. (2002, Hydrological Processes16: 2311,2327) proposed a probabilistic model of diffuse overland flow that predicted the hillslope lengths required to infiltrate road discharge, based on the concept of volume to breakthrough (Vbt). This paper extends this analysis to a different forest environment with the aim of testing the portability of the Hairsine et al. (2002) model. The volume of flow required to travel overland to a distance of 5 and 10 m (Vbt5 and Vbt10) from drainage outlets was measured in deep, highly conductive mountain soils in the Upper Tyers catchment, Victoria, Australia. Rainfall, hydraulic conductivity and soil depths contrasted markedly with those in the Hairsine et al. (2002) study, and represent an extreme in Australian forests. Statistical analyses revealed the population of Vbt5 to be indistinguishable from that observed by Hairsine et al. (2002), indicating the model is valid for a range of forest soils. There was no significant correlation of sediment plume length with site characteristics such as slope, width of flow, or existence of incised pathways. It is suggested there are universal properties of pathways draining tracks and roads, with bioturbation acting to restore available pore spaces filled by antecedent plumes. Drain discharge design criteria may be developed for local conditions using the Hairsine et al. (2002) model, providing a robust tool for protection of water quality in the siting of new forest roads, and maintenance of exiting roads and tracks. Copyright © 2006 John Wiley & Sons, Ltd. [source]

Long-term investigations of the snow cover in a subalpine semi-forested catchment

Manfred Stähli
Abstract To improve spring runoff forecasts from subalpine catchments, detailed spatial simulations of the snow cover in this landscape is obligatory. For more than 30 years, the Swiss Federal Research Institute WSL has been conducting extensive snow cover observations in the subalpine watershed Alptal (central Switzerland). This paper summarizes the conclusions from past snow studies in the Alptal valley and presents an analysis of 14 snow courses located at different exposures and altitudes, partly in open areas and partly in forest. The long-term performance of a physically based numerical snow,vegetation,atmosphere model (COUP) was tested with these snow-course measurements. One single parameter set with meteorological input variables corrected to the prevailing local conditions resulted in a convincing snow water equivalent (SWE) simulation at most sites and for various winters with a wide range of snow conditions. The snow interception approach used in this study was able to explain the forest effect on the SWE as observed on paired snow courses. Finally, we demonstrated for a meadow and a forest site that a successful simulation of the snowpack yields appropriate melt rates. Copyright © 2006 John Wiley & Sons, Ltd. [source]

,Distribution of oxygen-18 and deuterium in river waters across the United States

Carol Kendall
Abstract Reconstruction of continental palaeoclimate and palaeohydrology is currently hampered by limited information about isotopic patterns in the modern hydrologic cycle. To remedy this situation and to provide baseline data for other isotope hydrology studies, more than 4800, depth- and width-integrated, stream samples from 391 selected sites within the USGS National Stream Quality Accounting Network (NASQAN) and Hydrologic Benchmark Network (HBN) were analysed for ,18O and ,2H (http://water.usgs.gov/pubs/ofr/ofr00-160/pdf/ofr00-160.pdf). Each site was sampled bimonthly or quarterly for 2·5 to 3 years between 1984 and 1987. The ability of this dataset to serve as a proxy for the isotopic composition of modern precipitation in the USA is supported by the excellent agreement between the river dataset and the isotopic compositions of adjacent precipitation monitoring sites, the strong spatial coherence of the distributions of ,18O and ,2H, the good correlations of the isotopic compositions with climatic parameters, and the good agreement between the ,national' meteoric water line (MWL) generated from unweighted analyses of samples from the 48 contiguous states of ,2H=8·11,18O+8·99 (r2=0·98) and the unweighted global MWL of sites from the Global Network for Isotopes in Precipitation (GNIP) of the International Atomic Energy Agency and the World Meteorological Organization (WMO) of ,2H=8·17,18O+10·35. The national MWL is composed of water samples that arise in diverse local conditions where the local meteoric water lines (LMWLs) usually have much lower slopes. Adjacent sites often have similar LMWLs, allowing the datasets to be combined into regional MWLs. The slopes of regional MWLs probably reflect the humidity of the local air mass, which imparts a distinctive evaporative isotopic signature to rainfall and hence to stream samples. Deuterium excess values range from 6 to 15, in the eastern half of the USA, along the northwest coast and on the Colorado Plateau. In the rest of the USA, these values range from ,2 to 6,, with strong spatial correlations with regional aridity. The river samples have successfully integrated the spatial variability in the meteorological cycle and provide the best available dataset on the spatial distributions of ,18O and ,2H values of meteoric waters in the USA. Published in 2001 by John Wiley & Sons, Ltd. [source]

Privatization and the allure of franchising: a Zambian feasibility study,

John L. Fiedler
Abstract Efforts to privatize portions of the health sector have proven more difficult to implement than had been anticipated previously. One common bottleneck encountered has been the traditional organizational structure of the private sector, with its plethora of independent, single physician practices. The atomistic nature of the sector has rendered many privatization efforts difficult, slow and costly,in terms of both organizational development and administration. In many parts of Africa, in particular, the shortages of human and social capital, and the fragile nature of legal institutions, undermine the appeal of privatization. The private sector is left with inefficiencies, high prices and costs, and a reduced effective demand. The result is the simultaneous existence of excess capacity and unmet need. One potential method to improve the efficiency of the private sector, and thereby enhance the likelihood of successful privatization, is to transfer managerial technology,via franchising,from models that have proven successful elsewhere. This paper presents a feasibility analysis of franchizing the successful Bolivian PROSALUD system's management package to Zambia. The assessment, based on PROSALUD's financial model, demonstrates that technology transfer requires careful adaptation to local conditions and, in this instance, would still require significant external assistance. Copyright © 2003 John Wiley & Sons, Ltd. [source]

Service quality in hospital wards with different nursing organization: nurses' ratings

Ingeborg S. Sjetne
Abstract Title.,Service quality in hospital wards with different nursing organization: nurses' ratings. Aim., This paper is a report of a study to assess: (1) the relations between nursing organization models in hospital wards and nurses' perception of the quality of patient care and dimensions of the practice environment, and (2) if these relations were modified by variations in local conditions at the ward level. Background., Previous literature is inconclusive concerning what model of nursing organization maximizes the quality of nursing services. Method., A cross-sectional survey was carried out in a representative sample of Norwegian hospital wards in 2005. Intra-ward organization models were classified as: (1) Team leader (n = 30), characterized by extensive responsibilities for team leaders, (2) Primary nurse (n = 18), with extensive responsibilities for named nurses, and (3) Hybrid (n = 37), (1) and (2) combined. We prepared multilevel regression models using scales describing quality of patient care, learning climate, job satisfaction, and relationships with physicians as dependent variables. As independent variables, we used variables representing local ward conditions. Results., Eighty-seven wards and 1137 nurses (55% response rate) provided complete data. The ward level proportion of variance ranged from 0·10 (job satisfaction) to 0·22 (relationships with physicians). The univariate effect of organization models on quality ratings was not statistically significant. Introducing local ward conditions led to a statistically significant effect of primary nurse organization on relationships with physicians, and to a substantial proportional reduction in ward level variance, ranging from 32% (quality of patient care) to 24% (learning climate). Conclusion., Caution is needed about using service quality arguments when considering the possible benefits and drawbacks of different organizational models. [source]

Spatial relationships between intensive land cover and residual plant species diversity in temperate farmed landscapes

Summary 1In temperate farmed landscapes conservation policies increasingly emphasize large-scale reductions in land-use intensity. Yet despite a managed reversion to more favourable abiotic conditions, depleted regional species pools may prevent the re-assembly of target communities. 2Using national-scale survey data recorded across Great Britain in 1998, we investigated the extent to which grassland indicator plant species persisted on potential refuge habitats across a spatial gradient of intensive land cover in lowland 1-km squares. These habitats comprised road verges, field boundaries, watercourse banks and small biotope fragments. Intensive land cover comprised built land, arable and improved grassland. 3The rate of reduction in indicator species richness across the intensive land cover gradient was significantly lower in all potential refuge features than in surrounding fields and larger areas of habitat. 4The best refuge locations were watercourse banks and small biotopes. In both cases, indicator species richness was higher than adjacent fields at the lowest intensive land cover and stayed higher as intensive land cover increased. 5However, as intensive land cover increased, plant traits associated with higher nutrient availability were more prominently represented among indicator species. 6Although richer assemblages of indicator species persisted on refuge features, population sizes are likely to be small, because of species,area effects, and also vulnerable to nutrient surpluses and reduced or inappropriate disturbance. 7Synthesis and applications. Across the British lowlands, linear landscape features and small habitat fragments can provide limited safe havens for unimproved grassland plant species. However, the identity of refuge features and their species richness and composition are likely to vary with local conditions. Three activities are therefore paramount in assessing their role in larger scale extensification schemes: (i) development of rapid ways of assessing the plant diversity and distribution of refuge features in local areas; (ii) quantification of the risks posed to the viability of residual source populations through implementation of different options for incorporating them into extensification schemes; (iii) maximization of scheme performance by targeting landscapes with sufficient residual diversity to enable increases in population size of the target species in the medium term. [source]

Effects of climate and local aridity on the latitudinal and habitat distribution of Arvicanthis niloticus and Arvicanthis ansorgei (Rodentia, Murinae) in Mali

B. Sicard
Abstract Introduction, The genus Arvicanthis (Lesson 1842) (Rodentia: Murinae), usually referred to as the unstriped grass rat, is mainly distributed in savanna and grassland habitats of Sub-Saharan Africa. Among the four chromosomal forms of Arvicanthis recently differentiated in Western and Central Africa, the one with a diploid chromosomal number (2n) of 62 and an autosomal fundamental number (NFa) of 62 or 64 is ascribed to Arvicanthis niloticus (Demarest 1822), while the one with 2n = 62 and a NFa between 74 and 76 is referred to A. ansorgei (Thomas 1910). Despite the broad area of sympatry recently uncovered along the inner delta of the Niger river in Mali [details in Volobouev et al. (2002) Cytogenetics and Genome Research, 96, 250,260], the distribution of the two species is largely parapatric and follows the latitudinal patterns of the West-African biogeographical domains, which are related to the latitudinal patterns of annual rainfall in this region. Here, we analyse the suggestion that the two species show specific adaptations to differences in climate aridity. Methods, Karyologically screened animals were sampled in 19 localities in seasonally flooded regions located along the ,Niger' river in Mali and extending from 1100 to 200 mm of mean annual rainfall. The analysis of trapping success (TS) data allowed us to investigate the respective effects of climate (i.e. annual rainfall) and local (i.e. duration of the green herbaceous vegetation) aridity on the latitudinal and habitat distribution of the two species. Conclusions, The broad zone of sympatry was found to correspond to a northward expansion of the recognized distribution area of A. ansorgei. TS values indicated that the two species responded very differently to climatic and local conditions of aridity. Arvicanthis ansorgei decreased in TS as regional conditions became more arid; a similar trend was also observed within regions where habitat occupancy decreased with local aridity. The higher TS observed in the most humid habitat relative to the others persisted throughout the latitudinal rainfall gradient. In contrast, TS of A. niloticus increased with latitudinal aridity. This species was present in more arid habitats than A. ansorgei from 1000 mm down to 400 mm of mean annual rainfall where a shift to the most humid habitat occurred. These opposite trends in TS distribution between species suggest that A. ansorgei is less adapted than A. niloticus to arid environments at both a regional and habitat level; thus, A. ansorgei would be able to invade dry regions only along the extensive floodplains bordering the inner delta of the ,Niger' river. Several biological traits that may be involved in limiting the southward distribution of A. niloticus are discussed. [source]

Removal of heavy metals and cyanide from gold mine wastewater

Mike A. Acheampong
Abstract This paper reviews the technology and biotechnology to remove heavy metals (such as copper, arsenic, lead and zinc) and cyanide from contaminated wastewater. The paper places special emphasis on gold mine wastewater and the use of low cost materials as sorbent. Various biological as well as physicochemical treatment processes are discussed and compared on the basis of costs, energy requirement, removal efficiency, limitations and advantages. Sorption using natural plant materials, industrial and agricultural waste has been demonstrated to have the potential to replace conventional methods for the removal of heavy metals because of its cost effectiveness, efficiency and the local availability of these materials as biosorbent. The parameters affecting sorption, such as initial ion concentration, pH, sorbent dosage, particle size and temperature, are discussed. The overall treatment cost of metal and cyanide contaminated wastewater depends on the process employed and the local conditions. In general, technical applicability, cost-effectiveness and plant simplicity are the key factors in selecting the most suitable treatment method. Copyright © 2010 Society of Chemical Industry [source]

Regional variability of climate,growth relationships in Pinus cembra high elevation forests in the Alps

Summary 1The tree-ring growth response of stone pine (Pinus cembra L.) to climatic variability was studied in the Alps. The aims were (i) to assess tree-ring growth patterns at different spatial-temporal scales; (ii) to identify the climate parameters that explain most of the variability in radial growth at different time domains; and (iii) to study past and current trends in radial growth and climate,growth relationships at different locations. 2High- and low-frequency stone pine chronologies were compiled for 30 treeline sites on the French and Italian Alps. We used gridded climate data computed from 200 years of instrumental records from an extensive Alpine network. Climate,growth relationships were computed with bootstrap correlation functions and their stationarity and consistency over time assessed with moving correlation. 3No spatial patterns were detected in stone pine chronology statistics despite the regional clustering observed in tree-ring series and climate responses. This can be attributed to (i) local weather variability; (ii) different biophysical conditions caused by soil moisture, solar radiation, snowmelt dynamics and growing season length; and (iii) forest stand history and age structure, the expression of long-term land use and disturbances. 4The exceptionally long-term climate records allowed significant stone pine growth response changes to be assessed at both annual and decadal time scales. Winter conditions and spring,summer temperatures mainly affected the growing season length, in addition to site carbon and water balance. Most of these limiting factors varied spatially and temporally along the latitudinal and longitudinal gradients in response to the corresponding changes in local conditions. 5Our results show evidence of a clear response variability of Pinus cembra to climate limiting factors, at both spatial and temporal scale. Such knowledge extended to other species and regions will provide better estimates of the effect of climate variability on species distribution and dynamics within global change scenarios and more accurate past climate reconstruction and forest ecosystem modelling. [source]

Evaluation of window flight traps for effectiveness at monitoring dead wood-associated beetles: the effect of ethanol lure under contrasting environmental conditions

C. Bouget
Abstract 1,Subsequent to the diversity of saproxylic beetles being proposed as a management tool in forestry, more explicit knowledge about the efficiency and selective properties of beetle sampling methods is needed. 2,We compared saproxylic beetle assemblages caught by alcohol-baited or unbaited window traps in different forest contexts. Considering that trap attractiveness depends on kairomone concentrations, we appraised whether the trap efficiency was influenced by trap environment (openness and local supply of fresh dead wood). 3,Saproxylic beetles were sampled using 48 cross-vane window flight traps, arranged in paired designs (alcohol-baited/unbaited), in eight ancient and eight recent gaps (open stands), and eight closed-canopy control stands in an upland beech forest in the French Pyrenees. 4,Baited traps were more efficient than unbaited traps in terms of abundance and richness in our deciduous forests. The ethanol lure did not have any repellent effect on the individual response of saproxylic taxa. 5,The influence of local environmental conditions on trap attractiveness was observed. Openness had a significant moderate effect on species richness. Trap attractiveness was slightly reduced in the alcohol-saturated environment of recent gaps probably due to a disruption by local fresh dead-wood concentrations of the kairomonal response of saproxylic beetles to baited traps (,alcohol disruption'). 6,Because the ethanol lure enhanced the probability of species detection, it may be useful in early-warning surveillance, monitoring and control of wood borers, despite slight influences of local conditions on baited trap efficiency. [source]

Offering Incentives for New Development: The Role of City Social Status, Politics, and Local Growth Experiences

Paul G. Lewis
The propensity of municipal governments to offer incentives for new development is empirically examined, drawing upon both the literature on local economic development policy and studies of local residential restrictions. The data are from a 1998 mail survey of city managers in California in which officials assessed the likelihood that their local governments would offer financial assistance or zoning changes to various types of new business and residential land uses in their communities. Multivariate analysis indicates that local conditions resulting from past growth patterns,commuting times, job/population balance, and housing affordability,play an important role in shaping respondents' assessments as to whether their cities are likely to grant incentives. Such factors deserve an important role in explaining local government growth orientations, alongside measures of community status, political institutions, and the strength of progrowth coalitions. [source]

Are cattle, sheep, and goats endangered species?

Abstract For about 10 000 years, farmers have been managing cattle, sheep, and goats in a sustainable way, leading to animals that are well adapted to the local conditions. About 200 years ago, the situation started to change dramatically, with the rise of the concept of breed. All animals from the same breed began to be selected for the same phenotypic characteristics, and reproduction among breeds was seriously reduced. This corresponded to a strong fragmentation of the initial populations. A few decades ago, the selection pressures were increased again in order to further improve productivity, without enough emphasis on the preservation of the overall genetic diversity. The efficiency of modern selection methods successfully increased the production, but with a dramatic loss of genetic variability. Many industrial breeds now suffer from inbreeding, with effective population sizes falling below 50. With the development of these industrial breeds came economic pressure on farmers to abandon their traditional breeds, and many of these have recently become extinct as a result. This means that genetic resources in cattle, sheep, and goats are highly endangered, particularly in developed countries. It is therefore important to take measures that promote a sustainable management of these genetic resources; first, by in situ preservation of endangered breeds; second, by using selection programmes to restore the genetic diversity of industrial breeds; and finally, by protecting the wild relatives that might provide useful genetic resources. [source]

A culture of threat: Right-wing extremism and negative identity formation in German youth

Wolfgang Edelstein
The specific case of Eastern Germany is illustrative of a more general framework for how identity formation, family processes, and humiliation, alienation, and deprivation are linked to local conditions or situational contexts. [source]

Seasonal and spatial patterns of population density in the marine macroalga Mazzaella splendens (Gigartinales, Rhodophyta)

Leonard James Dyck
SUMMARY Insight into demographic processes that operate at larger spatial scales can be achieved through studying local populations when a particular species of interest is examined over time, by many investigators, in a variety of locations. On the west coast of North America, Mazzaella splendens (Setchell et Gardner) Fredericq is such a species of interest. A synthesis of local demographic studies of M. splendens from the late 1960s to the present reveals a pattern that is potentially common to the larger natural populations. This is the pattern: population density is high in summer and low in winter for both alternate free-living life history phases of M. splendens. The magnitude of this seasonal change decreases in increasingly wave-exposed habitats. In wave-sheltered habitats there is a seasonal alternation from summer haploid to winter diploid dominance. This alternation gradually changes to constant diploid dominance as wave exposure in the habitat increases. Changes in population density are primarily a function of appearances and disappearances of perennating basal crusts (genets), as modules are produced or lost, rather than differential module production by genets of one phase over those of the other. To test the generality of this pattern, we examined seasonal changes in density, in local populations of M. splendens, in both a wave-sheltered and a wave-exposed habitat at Second Beach, Barkley Sound. Greater seasonal fluctuation in population density at wave-sheltered, compared to wave-exposed habitats is supported as a pattern potentially common to the natural populations of M. splendens. A change from summer haploid dominance in wave-sheltered areas to summer diploid dominance in wave-exposed areas is similarly supported. All changes in population density were the result of appearances and disappearances of genets rather than differential module production by haploid versus diploid basal crusts, also consistent with previous observations. A seasonal alternation in phase dominance, however, was absent from the wave-sheltered site at Second Beach, Barkley Sound for 3 consecutive years. Seasonal alternation in phase dominance of M. splendens appears dependent on local conditions and is not common to all natural populations. [source]

Physiological distribution of placental growth factor and soluble Flt-1 in early pregnancy

George Makrydimas
Abstract Objective To examine the distribution of placental growth factor (PlGF), vascular endothelial growth factor (VEGF) and soluble VEGF receptor-1 (sFlt-1) in maternal and embryonic fluid compartments in early pregnancy. Method The concentrations of PlGF, VEGF and sFlt-1 were measured in coelomic fluid and maternal serum from 16 singleton pregnancies at 7.0,9.3 weeks. In six cases, amniotic fluid was also examined. Results The median concentration of PlGF was 14.1 (range 8.9,27.6) pg/mL in maternal serum, 13.9 (range 9.5,31.4) pg/mL in coelomic fluid and 8.9 (range 3.9,15.3) pg/mL in amniotic fluid. The concentration of PlGF increased between 7.0 and 9.3 weeks in maternal serum (p = 0.001) and decreased in coelomic and amniotic fluid (p = 0.001). The median concentration of sFlt-1 was 8561 (range 6724-10 673) pg/mL in coelomic fluid, 523 (range 244,986) pg/mL in maternal serum, 30 (range 12,83) pg/mL in amniotic fluid (p = 0.0001), and it did not change significantly with gestation. VEGF was undetectable in most of the samples, and therefore, no further analysis was performed. Conclusion PlGF and sFlt-1 are present in the maternal and fetal fluid compartments in very early pregnancy, and their distribution is consistent with their site of production and the local conditions of transport. Copyright © 2008 John Wiley & Sons, Ltd. [source]

How green is the valley?

Foreign direct investment in two Norwegian industrial towns
Since the early 1900s, foreign direct investments (FDIs) have greatly affected Norwegian society, especially peripheral communities. This article analyses how transnational corporations (TNCs) use territory down to the local level, and how this complex relationship between firms and spaces is shaped by attributes related to the TNC and the characteristics of the local economy. An extensive literature discusses different types of effects and spillovers, such as vertical supply linkages and spin-offs, but theoretical explanations of outcomes are more difficult. The literature links positive as well as negative outcomes to local conditions and to the investment motives of the entity making the FDI, but says little about how these vary with types of business, communities and national economies, and how these interactions generate different outcomes. We conclude that FDIs have different abilities to transform an area. We argue that FDI can trigger path-dependent dependency when it is dominated by economic capital and path-dependent development when it consists of a balance of economic capital, social networks and knowledge. This variation in the effects of FDI is illustrated by an empirical analysis of two industrial towns in Western Norway, one with natural resources and the other with intangible technology resources. Depuis le début des années 1900, les investissements directs à l'étranger (IDE) ont grandement marqué la société norvégienne, notamment dans les communautés périphériques. Cet article présente une analyse de la façon dont les entreprises transnationales (ETN) exploitent le territoire y compris le niveau local. Il tente aussi d'expliquer comment la relation complexe entre les entreprises et les espaces dépend des attributs propres aux ETN et des caractéristiques de l'économie locale. Un courant important de la littérature étudie les nombreuses incidences et répercussions des ETN, comme les relations d'offre verticale et les effets indirects. Cependant, les discussions qui s'ensuivent présentent généralement peu d'explications d'ordre théorique concernant les résultats. La littérature associe les résultats positifs ou négatifs directement aux conditions locales et aux motivations qui poussent une entreprise à placer ses capitaux dans un IDE. Elle aborde à peine la question sur comment les résultats peuvent varier selon les types d'entreprises, de communautés et d'économies nationales, et comment ces interactions produisent des résultats différents. En conclusion, nous rappelons que les IDE disposent de plusieurs possibilités de transformer un milieu. Un investissement peut produire une dépendance au sentier qui accentue la soumission quand le capital économique domine, et une dépendance au sentier qui accentue le développement quand il offre un équilibre entre le capital économique, les réseaux sociaux et le savoir. Une analyse empirique permet de relever cette variation qui caractérise les incidences des IDE. Elle porte sur deux villes moyennes industrielles situées dans la partie occidentale de la Norvège. La première est riche en ressources naturelles tandis que l'autre est dotée de ressources technologiques intangibles. [source]


This paper investigates the impact of overseas subsidiaries' R&D activities on the productivity growth of parent firms using firm-level data for Japanese multinational enterprises. Based on survey responses, we classify each overseas subsidiary's R&D as either ,innovative R&D,' which we hypothesize is likely to lead to the acquisition of foreign knowledge, or ,adaptive R&D,' which is more likely to lead to adaptation to local conditions. We find that overseas innovative R&D raises the parent firm's productivity growth, while adaptive R&D has no such effect. In addition, overseas innovative R&D does not improve the rate of return on home R&D. [source]

Atmospheric tides over the Pyrenees: observational study and numerical simulation

J. Díaz de Argandoña
Abstract Barometric tides around the Pyrenees mountain range are analyzed by means of synoptic surface-station data recorded during one year, surface data from the Pyrenees Experiment (PYREX) and the CRA/LA Very High Frequency (VHF) wind profiler installed in the north of the range. Tides are decomposed into their diurnal and semi-diurnal components. Diurnal tides show a strong non-migrating component and are very dependent on local conditions. Semi-diurnal tides are more homogeneous and present a north,south asymmetry, also noted in the Alps. This cross-range asymmetry could be related to some interference effect caused by the mountain range in the migrating semi-diurnal tide wave. The asymmetry of the diurnal component presents a very strong seasonal variation, probably related to local diabatic effects. A three-month long simulation has been carried out with the National Center for Atmospheric Research's Weather Research and Forecasting (WRF) limited-area model to try to reproduce the tide structure. The validation of the results with wind-profiler data shows reasonable agreement with the observed diurnal tide and poorer results for the semi-diurnal component. At surface level, however, the model reproduces some of the features of the observed semi-diurnal tide, and especially the cross-range asymmetry. Copyright © 2010 Royal Meteorological Society [source]


Miriam S. Chaiken
Anthropologists have long recognized the value of community participation in development planning and project implementation, and this paper discusses a new strategy to engage communities to monitor conditions of food insecurity and vulnerability, and to develop strategies for mitigation against shocks. Community based early warning programs (CEWS) complement existing hunger early warning systems that rely on satellite and agroclimatic data by collecting and monitoring data in rural communities. These strategies build on existing community awareness of local conditions, provide support for locally identified mitigation activities, and foster community participation. Examples from programs in Mozambique illustrate the potential of the CEWS strategies for effecting sustainable change and combating chronic food insecurity and vulnerability. [source]