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Sample records for change response explains

  1. Loss in Executive Functioning Best Explains Changes in Pain Responsiveness in Patients with Dementia-Related Cognitive Decline

    Directory of Open Access Journals (Sweden)

    Miriam Kunz

    2015-01-01

    Full Text Available There is ample evidence that dementia changes the processing of pain. However, it is not known whether this change in pain processing is related to the general decline in cognitive functioning or whether it may be related to specific domains of cognitive functioning. With the present study we tried to answer this question. We assessed different cognitive domains (orientation, memory, abstract thinking/executive function, aphasia and apraxia, and information processing speed in 70 older patients with cognitive impairment (mild cognitive impairment up to moderate degrees of dementia. Pain responsiveness was assessed by measuring the nociceptive flexion reflex (NFR threshold and facial responses to noxious electrical stimulation. Using regression analyses, we assessed which domain of cognitive functioning best predicted variance in pain responsiveness. Variance in pain responsiveness (NFR and facial expressions was best explained by those items assessing executive functioning even when controlling for overall cognitive performance and memory functioning. The close association between executive functioning and pain responsiveness suggests that dementia-related neurodegeneration in prefrontal areas might result not only in reduced executive functioning but also in a loss of pain inhibitory potency, rendering the patient more vulnerable to pain. Our findings also suggest that pain assessment in dementia should be regularly completed by tests of cognitive functions.

  2. Changes in the Size of the Active Microbial Pool Explain Short-Term Soil Respiratory Responses to Temperature and Moisture.

    Science.gov (United States)

    Salazar-Villegas, Alejandro; Blagodatskaya, Evgenia; Dukes, Jeffrey S

    2016-01-01

    Heterotrophic respiration contributes a substantial fraction of the carbon flux from soil to atmosphere, and responds strongly to environmental conditions. However, the mechanisms through which short-term changes in environmental conditions affect microbial respiration still remain unclear. Microorganisms cope with adverse environmental conditions by transitioning into and out of dormancy, a state in which they minimize rates of metabolism and respiration. These transitions are poorly characterized in soil and are generally omitted from decomposition models. Most current approaches to model microbial control over soil CO2 production relate responses to total microbial biomass (TMB) and do not differentiate between microorganisms in active and dormant physiological states. Indeed, few data for active microbial biomass (AMB) exist with which to compare model output. Here, we tested the hypothesis that differences in soil microbial respiration rates across various environmental conditions are more closely related to differences in AMB (e.g., due to activation of dormant microorganisms) than in TMB. We measured basal respiration (SBR) of soil incubated for a week at two temperatures (24 and 33°C) and two moisture levels (10 and 20% soil dry weight [SDW]), and then determined TMB, AMB, microbial specific growth rate, and the lag time before microbial growth (t lag ) using the Substrate-Induced Growth Response (SIGR) method. As expected, SBR was more strongly correlated with AMB than with TMB. This relationship indicated that each g active biomass C contributed ~0.04 g CO2-C h(-1) of SBR. TMB responded very little to short-term changes in temperature and soil moisture and did not explain differences in SBR among the treatments. Maximum specific growth rate did not respond to environmental conditions, suggesting that the dominant microbial populations remained similar. However, warmer temperatures and increased soil moisture both reduced t lag , indicating that favorable

  3. Loss in Executive Functioning Best Explains Changes in Pain Responsiveness in Patients with Dementia-Related Cognitive Decline

    NARCIS (Netherlands)

    Kunz, Miriam; Mylius, Veit; Schepelmann, Karsten; Lautenbacher, Stefan

    2015-01-01

    There is ample evidence that dementia changes the processing of pain. However, it is not known whether this change in pain processing is related to the general decline in cognitive functioning or whether it may be related to specific domains of cognitive functioning. With the present study we tried

  4. Shifts in the microbial community structure explain the response of soil respiration to land-use change but not to climate warming

    DEFF Research Database (Denmark)

    Nazaries, Loïc; Tottey, William; Robinson, Lucinda;

    2015-01-01

    of this feedback response of Rs to global change. To identify the mechanisms of Rs response to land-use change and climate warming, we first investigated Rs from different land use types. Soil respiration was estimated seasonally from four different Scottish land uses: moorland, birch woodland, grassland and pine......Soil stores more carbon (C) than plants and atmosphere combined and it is vulnerable to increased microbial respiration under projected global changes including land-use change and future climate scenarios (mainly elevated temperature). Land-use change is known to have a direct impact on soil...... organic C and soil respiration (Rs) but the mechanisms that drive these changes remain debatable. Similarly, recent studies and simulation models predict that Rs will respond positively to projected climate warming. However, there are significant uncertainties in the magnitude and mechanisms...

  5. The strong selective sweep candidate gene ADRA2C does not explain domestication related changes in the stress response of chickens.

    Directory of Open Access Journals (Sweden)

    Magnus Elfwing

    Full Text Available Analysis of selective sweeps to pinpoint causative genomic regions involved in chicken domestication has revealed a strong selective sweep on chromosome 4 in layer chickens. The autoregulatory α-adrenergic receptor 2C (ADRA2C gene is the closest to the selective sweep and was proposed as an important gene in the domestication of layer chickens. The ADRA2C promoter region was also hypermethylated in comparison to the non-selected ancestor of all domesticated chicken breeds, the Red Junglefowl, further supporting its relevance. In mice the receptor is involved in the fight-or-flight response as it modulates epinephrine release from the adrenals. To investigate the involvement of ADRA2C in chicken domestication, we measured gene expression in the adrenals and radiolabeled receptor ligand in three brain regions comparing the domestic White Leghorn strain with the wild ancestor Red Junglefowl. In adrenals ADRA2C was twofold greater expressed than the related receptor gene ADRA2A, indicating that ADRA2C is the predominant modulator of epinephrine release but no strain differences were measured. In hypothalamus and amygdala, regions associated with the stress response, and in striatum, receptor binding pIC50 values ranged between 8.1-8.4, and the level was not influenced by the genotyped allele. Because chicken strains differ in morphology, physiology and behavior, differences attributed to a single gene may be lost in the noise caused by the heterogeneous genetic background. Therefore an F10 advanced intercross strain between White Leghorn and Red Junglefowl was used to investigate effects of ADRA2C alleles on fear related behaviors and fecundity. We did not find compelling genotype effects in open field, tonic immobility, aerial predator, associative learning or fecundity. Therefore we conclude that ADRA2C is probably not involved in the domestication of the stress response in chicken, and the strong selective sweep is probably caused by selection

  6. Individualistic sensitivities and exposure to climate change explain variation in species' distribution and abundance changes.

    Science.gov (United States)

    Palmer, Georgina; Hill, Jane K; Brereton, Tom M; Brooks, David R; Chapman, Jason W; Fox, Richard; Oliver, Tom H; Thomas, Chris D

    2015-10-01

    The responses of animals and plants to recent climate change vary greatly from species to species, but attempts to understand this variation have met with limited success. This has led to concerns that predictions of responses are inherently uncertain because of the complexity of interacting drivers and biotic interactions. However, we show for an exemplar group of 155 Lepidoptera species that about 60% of the variation among species in their abundance trends over the past four decades can be explained by species-specific exposure and sensitivity to climate change. Distribution changes were less well predicted, but nonetheless, up to 53% of the variation was explained. We found that species vary in their overall sensitivity to climate and respond to different components of the climate despite ostensibly experiencing the same climate changes. Hence, species have undergone different levels of population "forcing" (exposure), driving variation among species in their national-scale abundance and distribution trends. We conclude that variation in species' responses to recent climate change may be more predictable than previously recognized. PMID:26601276

  7. Explaining international co-authorship in global environmental change research

    Energy Technology Data Exchange (ETDEWEB)

    Jappe, A.

    2006-04-15

    This paper maps the domain of earth and environmental sciences (EES) and investigates the relationship between cognitive problem structures and internationalisation patterns, drawing on the concepts of systemic versus cumulative global environmental change (GEC) and mutual task dependence in scientific fields. We find that scientific output concentration and internationalisation are significantly higher in the systemic GEC fields of Meteorology and Atmospheric Sciences and Oceanography than in the cumulative GEC fields Ecology and Water Resources. The relationship is explained by stronger mutual task dependence in systemic GEC fields. In contrast, the portion of co-authorships with developing, emerging and transition countries among all international publications is larger for Water Resources than for the three other fields, consistent with the most pressing needs for STI capacity development in these countries. (orig.)

  8. Explaining drug policy: Towards an historical sociology of policy change.

    Science.gov (United States)

    Seddon, Toby

    2011-11-01

    The goal of seeking to understand the development over time of drug policies is a specific version of the more general intellectual project of finding ways of explaining social change. The latter has been a preoccupation of some of the greatest thinkers within the social sciences of the last 200 years, from Foucault all the way back to the three nineteenth-century pioneers, Marx, Durkheim and Weber. I describe this body of work as 'historical sociology'. In this paper, I outline how a particular approach to historical sociology can be fruitfully drawn upon to understand the development of drug policy, using by way of illustration the example of the analysis of a recent transformation in British drug policy: the rise of the criminal justice agenda. I conclude by arguing that by looking at developments in drug policy in this way, some new insights are opened up.

  9. Reinforcement learning and counterfactual reasoning explain adaptive behavior in a changing environment.

    Science.gov (United States)

    Zhang, Yunfeng; Paik, Jaehyon; Pirolli, Peter

    2015-04-01

    Animals routinely adapt to changes in the environment in order to survive. Though reinforcement learning may play a role in such adaptation, it is not clear that it is the only mechanism involved, as it is not well suited to producing rapid, relatively immediate changes in strategies in response to environmental changes. This research proposes that counterfactual reasoning might be an additional mechanism that facilitates change detection. An experiment is conducted in which a task state changes over time and the participants had to detect the changes in order to perform well and gain monetary rewards. A cognitive model is constructed that incorporates reinforcement learning with counterfactual reasoning to help quickly adjust the utility of task strategies in response to changes. The results show that the model can accurately explain human data and that counterfactual reasoning is key to reproducing the various effects observed in this change detection paradigm.

  10. Circuit architecture explains functional similarity of bacterial heat shock responses

    CERN Document Server

    Inoue, Masayo; Trusina, Ala

    2012-01-01

    Heat shock response is a stress response to temperature changes and a consecutive increase in amounts of unfolded proteins. To restore homeostasis, cells upregulate chaperones facilitating protein folding by means of transcription factors (TF). We here investigate two heat shock systems: one characteristic to gram negative bacteria, mediated by transcriptional activator sigma32 in E. coli, and another characteristic to gram positive bacteria, mediated by transcriptional repressor HrcA in L. lactis. We construct simple mathematical model of the two systems focusing on the negative feedbacks, where free chaperons suppress sigma32 activation in the former, while they activate HrcA repression in the latter. We demonstrate that both systems, in spite of the difference at the TF regulation level, are capable of showing very similar heat shock dynamics. We find that differences in regulation impose distinct constrains on chaperone-TF binding affinities: the binding constant of free sigma32 to chaperon DnaK, known to...

  11. Circuit architecture explains functional similarity of bacterial heat shock responses

    International Nuclear Information System (INIS)

    Heat shock response is a stress response to temperature changes and a consecutive increase in amounts of unfolded proteins. To restore homeostasis, cells upregulate chaperones facilitating protein folding by means of transcription factors (TFs). We here investigate two heat shock systems: one characteristic to gram negative bacteria, mediated by transcriptional activator σ32 in E. coli, and another characteristic to gram positive bacteria, mediated by transcriptional repressor HrcA in L. lactis. We construct simple mathematical models of the two systems focusing on the negative feedbacks, where free chaperones suppress σ32 activation in the former, while they activate HrcA repression in the latter. We demonstrate that both systems, in spite of the difference at the TF regulation level, are capable of showing very similar heat shock dynamics. We find that differences in regulation impose distinct constraints on chaperone–TF binding affinities: the binding constant of free σ32 to chaperone DnaK, known to be in 100 nM range, set the lower limit of amount of free chaperone that the system can sense the change at the heat shock, while the binding affinity of HrcA to chaperone GroE set the upper limit and have to be rather large extending into the micromolar range. (paper)

  12. Explaining changes in food safety institutions in Hong Kong

    OpenAIRE

    Poon, Ping-yeung; 潘炳揚

    2014-01-01

    This dissertation examines changes in Hong Kong’s food safety institutions using an historical institutional approach. Hong Kong has faced enormous challenges in food safety over the last two decades. The avian flu crisis in 1997 and the malachite green crisis in 2005 were the two most notable examples. Both crises were recipes for institutional change. There was drastic reform in 2000 to form a unified food safety authority, the Food and Environmental Hygiene Department, to replace the old l...

  13. Quaternary climate changes explain diversity among reptiles and amphibians

    DEFF Research Database (Denmark)

    Bastos Araujo, Miguel; Nogués-Bravo, David; Diniz-Filho, Alexandre F.;

    2008-01-01

    debated without reaching consensus. Here, we test the proposition that European species richness of reptiles and amphibians is driven by climate changes in the Quaternary. We find that climate stability between the Last Glacial Maximum (LGM) and the present day is a better predictor of species richness...

  14. Changes in yield variability of major crops for 1981–2010 explained by climate change

    International Nuclear Information System (INIS)

    While changes in temperature and precipitation extremes are evident, their influence on crop yield variability remains unclear. Here we present a global analysis detecting yield variability change and attributing it to recent climate change using spatially-explicit global data sets of historical yields and an agro-climatic index based on daily weather data. The agro-climatic index used here is the sum of effective global radiation intercepted by the crop canopy during the yield formation stage that includes thresholds for extreme temperatures and extreme soil moisture deficit. Results show that year-to-year variations in yields of maize, soybean, rice and wheat in 1981–2010 significantly decreased in 19%–33% of the global harvested area with varying extent of area by crop. However, in 9%–22% of harvested area, significant increase in yield variability was detected. Major crop-producing regions with increased yield variability include maize and soybean in Argentina and Northeast China, rice in Indonesia and Southern China, and wheat in Australia, France and Ukraine. Examples of relatively food-insecure regions with increased yield variability are maize in Kenya and Tanzania and rice in Bangladesh and Myanmar. On a global scale, over 21% of the yield variability change could be explained by the change in variability of the agro-climatic index. More specifically, the change in variability of temperatures exceeding the optimal range for yield formation was more important in explaining the yield variability change than other abiotic stresses, such as temperature below the optimal range for yield formation and soil water deficit. Our findings show that while a decrease in yield variability is the main trend worldwide across crops, yields in some regions of the world have become more unstable, suggesting the need for long-term global yield monitoring and a better understanding of the contributions of technology, management, policy and climate to ongoing yield

  15. Regional distribution shifts help explain local changes in wintering raptor abundance: implications for interpreting population trends.

    Directory of Open Access Journals (Sweden)

    Neil Paprocki

    Full Text Available Studies of multiple taxa across broad-scales suggest that species distributions are shifting poleward in response to global climate change. Recognizing the influence of distribution shifts on population indices will be an important part of interpreting trends within management units because current practice often assumes that changes in local populations reflect local habitat conditions. However, the individual- and population-level processes that drive distribution shifts may occur across a large, regional scale and have little to do with the habitats within the management unit. We examined the latitudinal center of abundance for the winter distributions of six western North America raptor species using Christmas Bird Counts from 1975-2011. Also, we considered whether population indices within western North America Bird Conservation Regions (BCRs were explained by distribution shifts. All six raptors had significant poleward shifts in their wintering distributions over time. Rough-legged Hawks (Buteo lagopus and Golden Eagles (Aquila chrysaetos showed the fastest rate of change, with 8.41 km yr(-1 and 7.74 km yr(-1 shifts, respectively. Raptors may be particularly responsive to warming winters because of variable migration tendencies, intraspecific competition for nesting sites that drives males to winter farther north, or both. Overall, 40% of BCR population trend models were improved by incorporating information about wintering distributions; however, support for the effect of distribution on BCR indices varied by species with Rough-legged Hawks showing the most evidence. These results emphasize the importance of understanding how regional distribution shifts influence local-scale population indices. If global climate change is altering distribution patterns, then trends within some management units may not reflect changes in local habitat conditions. The methods used to monitor and manage bird populations within local BCRs will fundamentally

  16. Regional Distribution Shifts Help Explain Local Changes in Wintering Raptor Abundance: Implications for Interpreting Population Trends

    Science.gov (United States)

    Paprocki, Neil; Heath, Julie A.; Novak, Stephen J.

    2014-01-01

    Studies of multiple taxa across broad-scales suggest that species distributions are shifting poleward in response to global climate change. Recognizing the influence of distribution shifts on population indices will be an important part of interpreting trends within management units because current practice often assumes that changes in local populations reflect local habitat conditions. However, the individual- and population-level processes that drive distribution shifts may occur across a large, regional scale and have little to do with the habitats within the management unit. We examined the latitudinal center of abundance for the winter distributions of six western North America raptor species using Christmas Bird Counts from 1975–2011. Also, we considered whether population indices within western North America Bird Conservation Regions (BCRs) were explained by distribution shifts. All six raptors had significant poleward shifts in their wintering distributions over time. Rough-legged Hawks (Buteo lagopus) and Golden Eagles (Aquila chrysaetos) showed the fastest rate of change, with 8.41 km yr−1 and 7.74 km yr−1 shifts, respectively. Raptors may be particularly responsive to warming winters because of variable migration tendencies, intraspecific competition for nesting sites that drives males to winter farther north, or both. Overall, 40% of BCR population trend models were improved by incorporating information about wintering distributions; however, support for the effect of distribution on BCR indices varied by species with Rough-legged Hawks showing the most evidence. These results emphasize the importance of understanding how regional distribution shifts influence local-scale population indices. If global climate change is altering distribution patterns, then trends within some management units may not reflect changes in local habitat conditions. The methods used to monitor and manage bird populations within local BCRs will fundamentally change as

  17. Individualistic sensitivities and exposure to climate change explain variation in species’ distribution and abundance changes

    OpenAIRE

    Palmer, Georgina; Hill, Jane K.; Brereton, Tom M.; Brooks, David R; Chapman, Jason W.; Fox, Richard; Oliver, Tom H.; Thomas, Chris D.

    2015-01-01

    The responses of animals and plants to recent climate change vary greatly from species to species, but attempts to understand this variation have met with limited success. This has led to concerns that predictions of responses are inherently uncertain because of the complexity of interacting drivers and biotic interactions. However, we show for an exemplar group of 155 Lepidoptera species that about 60% of the variation among species in their abundance trends over the past four decades can be...

  18. Linking Native and Invader Traits Explains Native Spider Population Responses to Plant Invasion.

    Science.gov (United States)

    Smith, Jennifer N; Emlen, Douglas J; Pearson, Dean E

    2016-01-01

    Theoretically, the functional traits of native species should determine how natives respond to invader-driven changes. To explore this idea, we simulated a large-scale plant invasion using dead spotted knapweed (Centaurea stoebe) stems to determine if native spiders' web-building behaviors could explain differences in spider population responses to structural changes arising from C. stoebe invasion. After two years, irregular web-spiders were >30 times more abundant and orb weavers were >23 times more abundant on simulated invasion plots compared to controls. Additionally, irregular web-spiders on simulated invasion plots built webs that were 4.4 times larger and 5.0 times more likely to capture prey, leading to >2-fold increases in recruitment. Orb-weavers showed no differences in web size or prey captures between treatments. Web-spider responses to simulated invasion mimicked patterns following natural invasions, confirming that C. stoebe's architecture is likely the primary attribute driving native spider responses to these invasions. Differences in spider responses were attributable to differences in web construction behaviors relative to historic web substrate constraints. Orb-weavers in this system constructed webs between multiple plants, so they were limited by the overall quantity of native substrates but not by the architecture of individual native plant species. Irregular web-spiders built their webs within individual plants and were greatly constrained by the diminutive architecture of native plant substrates, so they were limited both by quantity and quality of native substrates. Evaluating native species traits in the context of invader-driven change can explain invasion outcomes and help to identify factors limiting native populations. PMID:27082240

  19. Linking Native and Invader Traits Explains Native Spider Population Responses to Plant Invasion.

    Science.gov (United States)

    Smith, Jennifer N; Emlen, Douglas J; Pearson, Dean E

    2016-01-01

    Theoretically, the functional traits of native species should determine how natives respond to invader-driven changes. To explore this idea, we simulated a large-scale plant invasion using dead spotted knapweed (Centaurea stoebe) stems to determine if native spiders' web-building behaviors could explain differences in spider population responses to structural changes arising from C. stoebe invasion. After two years, irregular web-spiders were >30 times more abundant and orb weavers were >23 times more abundant on simulated invasion plots compared to controls. Additionally, irregular web-spiders on simulated invasion plots built webs that were 4.4 times larger and 5.0 times more likely to capture prey, leading to >2-fold increases in recruitment. Orb-weavers showed no differences in web size or prey captures between treatments. Web-spider responses to simulated invasion mimicked patterns following natural invasions, confirming that C. stoebe's architecture is likely the primary attribute driving native spider responses to these invasions. Differences in spider responses were attributable to differences in web construction behaviors relative to historic web substrate constraints. Orb-weavers in this system constructed webs between multiple plants, so they were limited by the overall quantity of native substrates but not by the architecture of individual native plant species. Irregular web-spiders built their webs within individual plants and were greatly constrained by the diminutive architecture of native plant substrates, so they were limited both by quantity and quality of native substrates. Evaluating native species traits in the context of invader-driven change can explain invasion outcomes and help to identify factors limiting native populations.

  20. Morphological change to birds over 120 years is not explained by thermal adaptation to climate change.

    Directory of Open Access Journals (Sweden)

    Volker Salewski

    Full Text Available Changes in morphology have been postulated as one of the responses of animals to global warming, with increasing ambient temperatures leading to decreasing body size. However, the results of previous studies are inconsistent. Problems related to the analyses of trends in body size may be related to the short-term nature of data sets, to the selection of surrogates for body size, to the appropriate models for data analyses, and to the interpretation as morphology may change in response to ecological drivers other than climate and irrespective of size. Using generalized additive models, we analysed trends in three morphological traits of 4529 specimens of eleven bird species collected between 1889 and 2010 in southern Germany and adjacent areas. Changes and trends in morphology over time were not consistent when all species and traits were considered. Six of the eleven species displayed a significant association of tarsus length with time but the direction of the association varied. Wing length decreased in the majority of species but there were few significant trends in wing pointedness. Few of the traits were significantly associated with mean ambient temperatures. We argue that although there are significant changes in morphology over time there is no consistent trend for decreasing body size and therefore no support for the hypothesis of decreasing body size because of climate change. Non-consistent trends of change in surrogates for size within species indicate that fluctuations are influenced by factors other than temperature, and that not all surrogates may represent size appropriately. Future analyses should carefully select measures of body size and consider alternative hypotheses for change.

  1. Explaining Change and Stability in Cross-Strait Relations: A Punctuated Equilibrium Model

    OpenAIRE

    Hu, WR

    2012-01-01

    Relations across the Taiwan Strait have experienced several cycles over the last 60 years. Tension and crisis seem to come and go, followed by periods of peace and stability. What explains the cyclical pattern of change and stability? How can we explain the sources of change and stability in the relationship? This article examines the last 60 years of cross-Strait relations in light of an interpretative framework of ‘punctuated equilibrium’. Cross-Strait relations are complex, consisting of a...

  2. How to explain socially responsible corporate actions institutionally: theoretical and methodological critique

    OpenAIRE

    Sorsa, Ville-Pekka

    2008-01-01

    There has been little theoretical debate of why companies behave in socially responsible ways whilst descriptive analysis of corporate social responsibility is flourishing. As result, there have been few methodological debates on how to study both what responsible actions are and why companies act accordingly. This methodological and theoretical essay discusses how institutional social theory has been and could be used in explaining socially responsible corporate behaviour. It is explor...

  3. Cenozoic Mammals and Climate Change: The Contrast between Coarse-Scale versus High-Resolution Studies Explained by Species Sorting

    Directory of Open Access Journals (Sweden)

    Donald Prothero

    2012-04-01

    Full Text Available Many paleontologists have noticed the broadly similar patterns between the changes in Cenozoic mammalian diversity and taxonomic dominance and climate changes. Yet detailed studies of fossil population samples with fine-scale temporal resolution during episodes of climate change like the Eocene-Oligocene transition in the White River Group, and the late Pleistocene at Rancho La Brea tar pits, demonstrates that most fossil mammal species are static and show no significant microevolutionary response to major climate changes. This mismatch between patterns seems best explained by species sorting. As the punctuated equilibrium model demonstrated, over long time spans most fossil species are stable and do not respond to climate change. Instead, change occurs at the next hierarchical level, with species sorting adding and subtracting to the total diversity pattern revealed by coarse-scale taxon counting, apparently responding to longer-term changes in climate as revealed by proxies like the oxygen isotope record.

  4. A Hierarchical Bayes Error Correction Model to Explain Dynamic Effects of Price Changes

    NARCIS (Netherlands)

    D. Fok (Dennis); R. Paap (Richard); C. Horváth (Csilla); Ph.H.B.F. Franses (Philip Hans)

    2005-01-01

    textabstractThe authors put forward a sales response model to explain the differences in immediate and dynamic effects of promotional prices and regular prices on sales. The model consists of a vector autoregression rewritten in error-correction format which allows to disentangle the immediate effec

  5. Living in the tide of change: explaining Japanese subjective health from the socio-demographic change

    OpenAIRE

    Hitokoto, Hidefumi; Tanaka-Matsumi, Junko

    2014-01-01

    Today, countries around the world are caught in the tide of change toward Gesellshaft, or individualistic socio-demographic condition. Recent investigations in Japan have suggested negative impacts of change on emotional and motivational aspects of the Japanese self (Norasakkunkit et al., 2012; Ogihara and Uchida, 2014). Building on previous findings, in Study 1, we measured socio-demographic change toward individualistic societal condition during 1990–2010—two decades marked by great economi...

  6. Living in the tide of change: explaining Japanese subjective health from the socio-demographic change.

    Science.gov (United States)

    Hitokoto, Hidefumi; Tanaka-Matsumi, Junko

    2014-01-01

    Today, countries around the world are caught in the tide of change toward Gesellshaft, or individualistic socio-demographic condition. Recent investigations in Japan have suggested negative impacts of change on emotional and motivational aspects of the Japanese self (Norasakkunkit et al., 2012; Ogihara and Uchida, 2014). Building on previous findings, in Study 1, we measured socio-demographic change toward individualistic societal condition during 1990-2010-two decades marked by great economic recession-at the levels of prefecture and city using archival data. In Study 2, we tested whether Japanese adults' general health, satisfaction with life, self-esteem, and perceived social support were negatively predicted by the change using social survey. Results of hierarchical linear modeling showed small but unique negative effects of the change on several health measures, suggesting that this change had an impact on health, above and beyond individual personality traits, and demographics. Additionally, interdependent happiness, the type of cultural happiness grounded in interdependence of the self (Hitokoto and Uchida, 2014), showed an independent positive relationship with all aspects of health examined. Implications for health studies in changing socio-demographic condition are discussed in the context of Japanese society after economic crisis. PMID:25400604

  7. An Integrated Model to Explain How Corporate Social Responsibility Affects Corporate Financial Performance

    OpenAIRE

    Chin-Shien Lin; Ruei-Yuan Chang; Van Thac Dang

    2015-01-01

    The effect of corporate social responsibility (CSR) on financial performance has important implications for enterprises, communities, and countries, and the significance of this issue cannot be ignored. Therefore, this paper proposes an integrated model to explain the influence of CSR on financial performance with intellectual capital as a mediator and industry type as a moderator. Empirical results indicate that intellectual capital mediates the relationship between CSR and financial perform...

  8. Explaining life history variation in a changing climate across a species' range

    DEFF Research Database (Denmark)

    Neuheimer, Anna B.; MacKenzie, Brian R.

    2014-01-01

    Timing of reproduction greatly influences offspring success and resulting population production. Explaining and predicting species' dynamics necessitates disentangling the intrinsic (genotypic) and extrinsic (climatic) factors controlling reproductive timing. Here we explore temporal and spatial...... changes in spawning time for 21 populations of Atlantic cod (Gadus morhua) across the species' range (40 degrees to 80 degrees N). We estimate spawning time using a physiologically relevant metric that includes information on fish thermal history (degree-days, DD). First, we estimate spawning DD among...

  9. Climate and terrain factors explaining streamflow response and recession in Australian catchments

    Directory of Open Access Journals (Sweden)

    A. I. J. M. van Dijk

    2010-01-01

    Full Text Available Daily streamflow data were analysed to assess which climate and terrain factors best explain streamflow response in 183 Australian catchments. Assessed descriptors of catchment response included the parameters of fitted baseflow models, and baseflow index (BFI, average quick flow and average baseflow derived by baseflow separation. The variation in response between catchments was compared with indicators of catchment climate, morphology, geology, soils and land use. Spatial coherence in the residual unexplained variation was investigated using semi-variogram techniques. A linear reservoir model (one parameter; recession coefficient produced baseflow estimates as good as those obtained using a non-linear reservoir (two parameters and for practical purposes was therefore considered an appropriate balance between simplicity and explanatory performance. About a third (27–34% of the spatial variation in recession coefficients and BFI was explained by catchment climate indicators, with another 53% of variation being spatially correlated over distances of 100–150 km, probably indicative of substrate characteristics not captured by the available soil and geology data. The shortest recession half-times occurred in the driest catchments and were attributed to intermittent occurrence of fast-draining (possibly perched groundwater. Most (70–84% of the variation in average baseflow and quick flow was explained by rainfall and climate characteristics; another 20% of variation was spatially correlated over distances of 300–700 km, possibly reflecting a combination of terrain and climate factors. It is concluded that catchment streamflow response can be predicted quite well on the basis of catchment climate alone. The prediction of baseflow recession response should be improved further if relevant substrate properties were identified and measured.

  10. Leaders as Corporate Responsibility Spokesperson: How Leaders Explain Liabilites Via Corporate Web Sites?

    Directory of Open Access Journals (Sweden)

    Burcu Öksüz

    2014-12-01

    Full Text Available The aim of this paper is to reveal the corporate social responsibility (CSR understandings of corporations from the leaders’ perspective and discuss how leaders define and explain CSR practices their organizations executed as spokesperson via social media channels of their organizations.  In this context, a content analysis aiming to display the ideas of Turkey’s top 250 corporations’ leaders (CEO, chairman of the board, general manager designated by Istanbul Chamber of Industry in 2013. The leader messages about different dimensions of CSR and CSR practices that are partaking in corporate web sites were examined. According to the results of the analysis, it is found that the leaders act as responsible leaders, and also the spokesperson of their corporations. In addition it is found out that responsible leaders included multiplexed information on different dimensions and various practices of CSR in their social media messages.

  11. Are low Danish fertility rates explained by changes in timing of births?

    DEFF Research Database (Denmark)

    Hvidtfeldt, Ulla A; Gerster, Mette; Knudsen, Lisbeth B;

    2010-01-01

    from the Danish Fertility of Women and Couples Dataset, 1980-2001. We evaluated fluctuations in period fertility rates by the tempo-adjusted TFR(') - a proposed variant of the conventional TFR(p) taking period changes in timing of births into account. Tempo-effects were given by the difference between......AIMS: The most commonly used indicator of fertility, the period total fertility rate (TFR(p)), tends to underestimate actual fertility when women delay childbearing. The objective of this study was to examine to which extent fluctuations in Danish fertility rates result from changes in timing...... of births and, thus, whether the conventional TFR(p) is a distorted indicator of fertility quantum. In addition, we investigated whether such changes in timing explained the observed regional differences in the TFR(p) in Denmark. METHODS: The study applied age-, period-, county-, and parity-specific data...

  12. Psychophysiological responses to auditory change.

    Science.gov (United States)

    Chuen, Lorraine; Sears, David; McAdams, Stephen

    2016-06-01

    A comprehensive characterization of autonomic and somatic responding within the auditory domain is currently lacking. We studied whether simple types of auditory change that occur frequently during music listening could elicit measurable changes in heart rate, skin conductance, respiration rate, and facial motor activity. Participants heard a rhythmically isochronous sequence consisting of a repeated standard tone, followed by a repeated target tone that changed in pitch, timbre, duration, intensity, or tempo, or that deviated momentarily from rhythmic isochrony. Changes in all parameters produced increases in heart rate. Skin conductance response magnitude was affected by changes in timbre, intensity, and tempo. Respiratory rate was sensitive to deviations from isochrony. Our findings suggest that music researchers interpreting physiological responses as emotional indices should consider acoustic factors that may influence physiology in the absence of induced emotions. PMID:26927928

  13. An Integrated Model to Explain How Corporate Social Responsibility Affects Corporate Financial Performance

    Directory of Open Access Journals (Sweden)

    Chin-Shien Lin

    2015-06-01

    Full Text Available The effect of corporate social responsibility (CSR on financial performance has important implications for enterprises, communities, and countries, and the significance of this issue cannot be ignored. Therefore, this paper proposes an integrated model to explain the influence of CSR on financial performance with intellectual capital as a mediator and industry type as a moderator. Empirical results indicate that intellectual capital mediates the relationship between CSR and financial performance, and industry type moderates the direct influence of CSR on financial performance. Such results have critical implications for both academia and practice.

  14. Phenotypic plasticity alone cannot explain climate-induced change in avian migration timing

    OpenAIRE

    Buskirk, Josh; Mulvihill, Robert S; Leberman, Robert C

    2012-01-01

    Recent climate change has been linked to shifts in the timing of life-cycle events in many organisms, but there is debate over the degree to which phenological changes are caused by evolved genetic responses of populations or by phenotypic plasticity of individuals. We estimated plasticity of spring arrival date in 27 species of bird that breed in the vicinity of an observatory in eastern North America. For 2441 individuals detected in multiple years, arrival occurred earlier during warm year...

  15. Alterations in gait speed and age do not fully explain the changes in gait mechanics associated with healthy older women.

    Science.gov (United States)

    Alcock, L; Vanicek, N; O'Brien, T D

    2013-04-01

    Older adults exhibit modified gait patterns compared to the young, adopting movement strategies in response to changes in musculoskeletal function. Investigating the functional mobility of older women is particularly important because of their increased life expectancy and greater falls risk compared to men. We explored the relationships between gait parameters and age in healthy older women whilst accounting for declining gait speeds. Kinematic and kinetic data were collected from thirty-nine women (60-83 years) whilst walking at a comfortable cadence. Regression analysis assessed the capacity of gait speed and age to explain the variance in gait associated with older age. Speed explained the majority of variance in many gait parameters. By including age in the regression, the total explained variance (R2) for foot clearance (70%), ankle plantarflexion angle (30%), peak ankle plantarflexor moment (58%), and hip power generation (56%) were significantly (pgait mechanics associated with older age and other contributing factors must exist. Losses of 1.2%/year in gait speed were predicted by age, exceeding previous predictions of -0.7%/year. Furthermore, the accumulation of apparently small decreases of 0.2 cm/year in peak foot-to-ground clearance has clinical implications and offers insight into the mechanisms by which gait becomes hazardous in older age.

  16. Changes in materials properties explain the effects of humidity on gecko adhesion.

    Science.gov (United States)

    Puthoff, Jonathan B; Prowse, Michael S; Wilkinson, Matt; Autumn, Kellar

    2010-11-01

    Geckos owe their remarkable stickiness to millions of dry setae on their toes, and the mechanism of adhesion in gecko setae has been the topic of scientific scrutiny for over two centuries. Previously, we demonstrated that van der Waals forces are sufficient for strong adhesion and friction in gecko setae, and that water-based capillary adhesion is not required. However, recent studies demonstrated that adhesion increases with relative humidity (RH) and proposed that surface hydration and capillary water bridge formation is important or even necessary. In this study, we confirmed a significant effect of RH on gecko adhesion, but rejected the capillary adhesion hypothesis. While contact forces of isolated tokay gecko setal arrays increased with humidity, the increase was similar on hydrophobic and hydrophilic surfaces, inconsistent with a capillary mechanism. Contact forces increased with RH even at high shear rates, where capillary bridge formation is too slow to affect adhesion. How then can a humidity-related increase in adhesion and friction be explained? The effect of RH on the mechanical properties of setal β-keratin has escaped consideration until now. We discovered that an increase in RH softens setae and increases viscoelastic damping, which increases adhesion. Changes in setal materials properties, not capillary forces, fully explain humidity-enhanced adhesion, and van der Waals forces remain the only empirically supported mechanism of adhesion in geckos. PMID:20952618

  17. A dynamic systems approach to psychotherapy: A meta-theoretical framework for explaining psychotherapy change processes.

    Science.gov (United States)

    Gelo, Omar Carlo Gioacchino; Salvatore, Sergio

    2016-07-01

    Notwithstanding the many methodological advances made in the field of psychotherapy research, at present a metatheoretical, school-independent framework to explain psychotherapy change processes taking into account their dynamic and complex nature is still lacking. Over the last years, several authors have suggested that a dynamic systems (DS) approach might provide such a framework. In the present paper, we review the main characteristics of a DS approach to psychotherapy. After an overview of the general principles of the DS approach, we describe the extent to which psychotherapy can be considered as a self-organizing open complex system, whose developmental change processes are described in terms of a dialectic dynamics between stability and change over time. Empirical evidence in support of this conceptualization is provided and discussed. Finally, we propose a research design strategy for the empirical investigation of psychotherapy from a DS approach, together with a research case example. We conclude that a DS approach may provide a metatheoretical, school-independent framework allowing us to constructively rethink and enhance the way we conceptualize and empirically investigate psychotherapy. (PsycINFO Database Record PMID:27177027

  18. A dynamic systems approach to psychotherapy: A meta-theoretical framework for explaining psychotherapy change processes.

    Science.gov (United States)

    Gelo, Omar Carlo Gioacchino; Salvatore, Sergio

    2016-07-01

    Notwithstanding the many methodological advances made in the field of psychotherapy research, at present a metatheoretical, school-independent framework to explain psychotherapy change processes taking into account their dynamic and complex nature is still lacking. Over the last years, several authors have suggested that a dynamic systems (DS) approach might provide such a framework. In the present paper, we review the main characteristics of a DS approach to psychotherapy. After an overview of the general principles of the DS approach, we describe the extent to which psychotherapy can be considered as a self-organizing open complex system, whose developmental change processes are described in terms of a dialectic dynamics between stability and change over time. Empirical evidence in support of this conceptualization is provided and discussed. Finally, we propose a research design strategy for the empirical investigation of psychotherapy from a DS approach, together with a research case example. We conclude that a DS approach may provide a metatheoretical, school-independent framework allowing us to constructively rethink and enhance the way we conceptualize and empirically investigate psychotherapy. (PsycINFO Database Record

  19. Working memory gating mechanisms explain developmental change in rule-guided behavior.

    Science.gov (United States)

    Unger, Kerstin; Ackerman, Laura; Chatham, Christopher H; Amso, Dima; Badre, David

    2016-10-01

    Cognitive control requires choosing contextual information to update into working memory (input gating), maintaining it there (maintenance) stable against distraction, and then choosing which subset of maintained information to use in guiding action (output gating). Recent work has raised the possibility that the development of rule-guided behavior, in the transition from childhood to adolescence, is linked specifically to changes in the gating components of working memory (Amso, Haas, McShane, & Badre, 2014). Given the importance of effective rule-guided behavior for decision making in this developmental transition, we used hierarchical rule tasks to probe the precise developmental dynamics of working memory gating. This mechanistic precision informs ongoing efforts to train cognitive control and working memory operations across typical and atypical development. The results of Experiment 1 verified that the development of rule-guided behavior is uniquely linked to increasing hierarchical complexity but not to increasing maintenance demands across 1st, 2nd, and 3rd order rule tasks. Experiment 2 then investigated whether this developmental trajectory in rule-guided behavior is best explained by change in input gating or output gating. Further, as input versus output gating also tend to correlate with a more proactive versus reactive control strategy in these tasks, we assessed developmental change in the degree to which these two processes were deployed efficiently given the task. Experiment 2 shows that the developmental change observed in Experiment 1 and in Amso et al. (2014) is likely a result of increased efficacy of output gating processes, as well as greater strategic efficiency in that adolescents opt for this costly process less often than children. PMID:27336178

  20. Delayed response and biosonar perception explain movement coordination in trawling bats.

    Science.gov (United States)

    Giuggioli, Luca; McKetterick, Thomas J; Holderied, Marc

    2015-03-01

    Animal coordinated movement interactions are commonly explained by assuming unspecified social forces of attraction, repulsion and alignment with parameters drawn from observed movement data. Here we propose and test a biologically realistic and quantifiable biosonar movement interaction mechanism for echolocating bats based on spatial perceptual bias, i.e. actual sound field, a reaction delay, and observed motor constraints in speed and acceleration. We found that foraging pairs of bats flying over a water surface swapped leader-follower roles and performed chases or coordinated manoeuvres by copying the heading a nearby individual has had up to 500 ms earlier. Our proposed mechanism based on the interplay between sensory-motor constraints and delayed alignment was able to recreate the observed spatial actor-reactor patterns. Remarkably, when we varied model parameters (response delay, hearing threshold and echolocation directionality) beyond those observed in nature, the spatio-temporal interaction patterns created by the model only recreated the observed interactions, i.e. chases, and best matched the observed spatial patterns for just those response delays, hearing thresholds and echolocation directionalities found to be used by bats. This supports the validity of our sensory ecology approach of movement coordination, where interacting bats localise each other by active echolocation rather than eavesdropping. PMID:25811627

  1. Delayed response and biosonar perception explain movement coordination in trawling bats.

    Directory of Open Access Journals (Sweden)

    Luca Giuggioli

    2015-03-01

    Full Text Available Animal coordinated movement interactions are commonly explained by assuming unspecified social forces of attraction, repulsion and alignment with parameters drawn from observed movement data. Here we propose and test a biologically realistic and quantifiable biosonar movement interaction mechanism for echolocating bats based on spatial perceptual bias, i.e. actual sound field, a reaction delay, and observed motor constraints in speed and acceleration. We found that foraging pairs of bats flying over a water surface swapped leader-follower roles and performed chases or coordinated manoeuvres by copying the heading a nearby individual has had up to 500 ms earlier. Our proposed mechanism based on the interplay between sensory-motor constraints and delayed alignment was able to recreate the observed spatial actor-reactor patterns. Remarkably, when we varied model parameters (response delay, hearing threshold and echolocation directionality beyond those observed in nature, the spatio-temporal interaction patterns created by the model only recreated the observed interactions, i.e. chases, and best matched the observed spatial patterns for just those response delays, hearing thresholds and echolocation directionalities found to be used by bats. This supports the validity of our sensory ecology approach of movement coordination, where interacting bats localise each other by active echolocation rather than eavesdropping.

  2. Silent Polymorphisms: Can the tRNA Population Explain Changes in Protein Properties?

    Science.gov (United States)

    Fernández-Calero, Tamara; Cabrera-Cabrera, Florencia; Ehrlich, Ricardo; Marín, Mónica

    2016-01-01

    Silent mutations are being intensively studied. We previously showed that the estrogen receptor alpha Ala87’s synonymous polymorphism affects its functional properties. Whereas a link has been clearly established between the effect of silent mutations, tRNA abundance and protein folding in prokaryotes, this connection remains controversial in eukaryotic systems. Although a synonymous polymorphism can affect mRNA structure or the interaction with specific ligands, it seems that the relative frequencies of isoacceptor tRNAs could play a key role in the protein-folding process, possibly through modulation of translation kinetics. Conformational changes could be subtle but enough to cause alterations in solubility, proteolysis profiles, functional parameters or intracellular targeting. Interestingly, recent advances describe dramatic changes in the tRNA population associated with proliferation, differentiation or response to chemical, physical or biological stress. In addition, several reports reveal changes in tRNAs’ posttranscriptional modifications in different physiological or pathological conditions. In consequence, since changes in the cell state imply quantitative and/or qualitative changes in the tRNA pool, they could increase the likelihood of protein conformational variants, related to a particular codon usage during translation, with consequences of diverse significance. These observations emphasize the importance of genetic code flexibility in the co-translational protein-folding process. PMID:26901226

  3. An insulin based model to explain changes and interactions in human breath-holding.

    Science.gov (United States)

    Dangmann, Rosita

    2015-06-01

    Until now oxygen was thought to be the leading factor of hypoxic conditions. Whereas now it appears that insulin is the key regulator of hypoxic conditions. Insulin seems to regulate the redox state of the organism and to determine the breakpoint of human breath-holding. This new hypoxia-insulin hypotheses might have major clinical relevance. Besides the clinical relevance, this hypothesis could explain, for the first time, why the training of the diaphragm, among other factors, results in an increase in breath-holding performance. Elite freedivers/apnea divers are able to reach static breath-holding times to over 6 min. Untrained persons exhibit an unpleasant feeling after more or less a minute. Breath-holding is stopped at the breakpoint. The partial oxygen pressure as well as the carbon dioxide pressure failed to directly influence the breakpoint in earlier studies. The factors that contribute to the breakpoint are still under debate. Under hypoxic conditions the organism needs more glucose, because it changes from the oxygen consuming pentose phosphate (36 ATP/glucose molecule) to the anaerobic glycolytic pathway (2ATP/glucose molecule). Hence insulin, as it promotes the absorption of glucose, is set in the center of interest regarding hypoxic conditions. This paper provides an insulin based model that could explain the changes and interactions in human breath-holding. The correlation between hypoxia and reactive oxygen species (ROS) and their influence on the sympathetic nerve system and hypoxia-inducible factor 1 alpha (HIF-1α) is dealt with. It reviews as well the direct interrelation of HIF-1α and insulin. The depression of insulin secretion through the vagus nerve activation via inspiration is discussed. Furthermore the paper describes the action of insulin on the carotid bodies and the diaphragm and therefore a possible role in respiration pattern. Freedivers that go over the breakpoint of breath-holding could exhibit seizures and thus the effect of

  4. How can one explain changes in the monthly pattern of suicide?

    CERN Document Server

    Roehner, Bertrand M

    2014-01-01

    The monthly pattern of suicides has remained a puzzle ever since it was discovered in the second half of the 19th century. In this paper we intend to "explain" not the pattern itself but rather its changes across countries and in the course of time. First, we show that the fairly common idea according to which this pattern is decaying in "modern" societies is not altogether true. For instance, around 2000, in well urbanized countries like South Korea or Spain this pattern was still as strong as it was in France (and other European countries) in the late 19th century. The method that we use in order to make some progress in our understanding is the time-honoured Cartesian approach of breaking up the problem under consideration "into as many parts as might be necessary to solve it". More specifically, we try two decompositions of monthly suicides: (i) according to suicide methods (ii) according to age-groups. The first decomposition points out the key-role of hanging and drowning. The second shows the crucial r...

  5. Permafrost carbon as a missing link to explain CO 2 changes during the last deglaciation

    Science.gov (United States)

    Crichton, K. A.; Bouttes, N.; Roche, D. M.; Chappellaz, J.; Krinner, G.

    2016-09-01

    The atmospheric concentration of CO2 increased from 190 to 280 ppm between the last glacial maximum 21,000 years ago and the pre-industrial era. This CO2 rise and its timing have been linked to changes in the Earth’s orbit, ice sheet configuration and volume, and ocean carbon storage. The ice-core record of δ13CO2 (refs ,) in the atmosphere can help to constrain the source of carbon, but previous modelling studies have failed to capture the evolution of δ13CO2 over this period. Here we show that simulations of the last deglaciation that include a permafrost carbon component can reproduce the ice core records between 21,000 and 10,000 years ago. We suggest that thawing permafrost, due to increasing summer insolation in the northern hemisphere, is the main source of CO2 rise between 17,500 and 15,000 years ago, a period sometimes referred to as the Mystery Interval. Together with a fresh water release into the North Atlantic, much of the CO2 variability associated with the Bølling-Allerod/Younger Dryas period ~15,000 to ~12,000 years ago can also be explained. In simulations of future warming we find that the permafrost carbon feedback increases global mean temperature by 10-40% relative to simulations without this feedback, with the magnitude of the increase dependent on the evolution of anthropogenic carbon emissions.

  6. Road user behaviour changes following a self-explaining roads intervention.

    Science.gov (United States)

    Mackie, Hamish W; Charlton, Samuel G; Baas, Peter H; Villasenor, Pablo C

    2013-01-01

    The self-explaining roads (SER) approach uses road designs that evoke correct expectations and driving behaviours from road users to create a safe and user-friendly road network. Following the implementation of an SER process and retrofitting of local and collector roads in a suburb within Auckland City, lower speeds on local roads and less variation in speed on both local and collector roads were achieved, along with a closer match between actual and perceived safe speeds. Preliminary analyses of crash data shows that the project has resulted in a 30% reduction crash numbers and an 86% reduction in crash costs per annum, since the road changes were completed. In order to further understand the outcomes from this project, a study was carried out to measure the effects of the SER intervention on the activity and behaviour of all road users. Video was collected over nine separate days, at nine different locations, both before and after SER construction. Road user behaviour categories were developed for all potential road users at different location types and then used to code the video data. Following SER construction, on local roads there was a relatively higher proportion of pedestrians, less uniformity in vehicle lane keeping and less indicating by motorists along with less through traffic, reflecting a more informal/low speed local road environment. Pedestrians were less constrained on local roads following SER construction, possibly reflecting a perceptually safer and more user-friendly environment. These behaviours were not generally evident on collector roads, a trend also shown by the previous study of speed changes. Given that one of the objectives of SER is to match road user behaviour with functionally different road categories, the road user behaviour differences demonstrated on different road types within the SER trial area provides further reinforcement of a successful SER trial.

  7. Climate change effects on enchytraeid performance in metal-polluted soils explained from changes in metal bioavailability and bioaccumulation.

    Science.gov (United States)

    González-Alcaraz, M Nazaret; van Gestel, Cornelis A M

    2015-10-01

    Climate change may alter physical, chemical and biological properties of ecosystems, affecting organisms but also the fate of chemical pollutants. This study aimed to find out how changes in climate conditions (air temperature, soil moisture content) affect the toxicity of metal-polluted soils to the soft-bodied soil organism Enchytraeus crypticus, linking enchytraeid performance with changes in soil available and body metal concentrations. Bioassays with E. crypticus were performed under different combinations of air temperature (20 and 25 °C) and soil moisture content (50% and 30% of the soil water holding capacity, WHC) in dilution series of three metal-polluted soils (mine tailing, forest and watercourse). After 21 d exposure, enchytraeid reproduction was determined, and soil available (extracted with 0.01 M CaCl2) and body Cd, Cu, Pb and Zn concentrations in surviving adults were determined. In general, Cd, Pb and Zn availability decreased upon incubation under the different climate scenarios. In the watercourse soil, with initially higher available metal concentrations (678 µg Cd kg(-1), 807 µg Pb kg(-1) and 31,020 µg Zn kg(-1)), decreases were greatest at 50% WHC probably due to metal immobilization as carbonates. Enchytraeid reproduction was negatively affected by higher available metal concentrations, with reductions up to 98% in the watercourse soil compared to the control soil at 30% WHC. Bioaccumulation of Cd, Pb and Zn was higher when drier conditions were combined with the higher temperature of 25 °C. Changes in metal bioavailability and bioaccumulation explained the toxicity of soil polluted by metal mine wastes to enchytraeids under changing environmental conditions. PMID:26162961

  8. Cerebrovascular responses during rowing: Do circadian rhythms explain morning and afternoon performance differences?

    Science.gov (United States)

    Faull, O K; Cotter, J D; Lucas, S J E

    2015-08-01

    The purpose of this study was to characterize cerebrovascular responses to rowing exercise, investigating whether their diurnal variation might explain performance differences across a day. Twelve male rowers completed incremental rowing exercise and a 2000-m ergometer time trial at 07:00 h and 16:00 h, 1 week apart, while middle cerebral artery velocity (MCAv), cerebral (prefrontal), and muscular (vastus lateralis) tissue oxygenation and hemoglobin volume (via near-infrared spectroscopy), heart rate, and pressure of end-tidal CO2 (PET CO2) were recorded. MCAv was 20-25% above resting levels (68 ± 12 cm/s) during submaximal and maximal exercise intensities, despite PET CO2 being reduced during maximal efforts (down ∼ 0.5-0.8 kPa); thus revealing a different perfusion profile to the inverted-U observed in other exercise modes. The afternoon time trial was 3.4 s faster (95% confidence interval 0.9-5.8 s) and mean power output 3.2% higher (337 vs 347 W; P = 0.04), in conjunction with similar exercise-induced elevations in MCAv (P = 0.60) and reductions in cerebral oxygenation (TOI) (P = 0.12). At the muscle, afternoon trials involved similar oxygen extraction (HHb volume and TOI) albeit from a relatively lower total Hb volume (P rowing performance was better in the afternoon, but not in conjunction with differences in MCAv or exercise-induced differences in cerebral oxygenation. PMID:24942089

  9. Explaining change over time in quality of life of adult patients with anorectal malformations or Hirschsprung's disease

    NARCIS (Netherlands)

    Hartman, EE; Oort, FJ; Visser, MR; Sprangers, MA; Hanneman, MJG; de Langen, ZJ; van Heurn, LWE; Rieu, PNMA; Madern, GC; van der Zee, DC; Looyaard, N; van Silfhout-Bezemer, M; Aronson, DC

    2006-01-01

    PURPOSE: The aim of this study was to examine changes in the quality of life of adult patients with anorectal malformations or Hirschsprung's disease over a three-year interval and to identify demographic, clinical, and psychosocial variables that explain possible quality-of-life changes. Understand

  10. How Well Do the Sticky Price Models Explain the Disaggregated Price Responses to Aggregate Technology and Monetary Policy Shocks?

    OpenAIRE

    Jouchi Nakajima; Nao Sudo; Takayuki Tsuruga

    2010-01-01

    This paper documents empirically and analyzes theoretically the responses of disaggregated prices to aggregate technology and monetary policy shocks. Based on the price data of US personal consumption expenditure, we find that disaggregated price responses have features across shocks and across sectors that are difficult to explain using standard multi-sector sticky price models. In terms of shocks, a substantial fraction of disaggregated prices initially rise in response to a contractionary ...

  11. Land Cover and Nutrient Loads Explain Changes in Enzymatic Processing of Stream Dissolved Organic Matter

    Science.gov (United States)

    Hosen, J. D.; Febria, C.; McDonough, O.; Palmer, M.

    2012-12-01

    Anthropogenic land use has been shown to alter organic matter composition as well as its processing, export, and retention in headwater streams. Human activities also increase stream nutrient loading and in turn organic matter processing by heterotrophic microbial communities. Using microbial extracellular enzyme activity (EEA) assays combined with dissolved organic matter (DOM) fluorescence spectroscopy, we investigated the interaction between catchment land use, nutrient limitation, heterotrophic microbial communities, and carbon processing in five forested and three urbanized Coastal Plain headwater streams (Maryland, USA). EEA measures microbial production of heterotrophic extracellular enzymes, including aminopeptidase, which facilitates the breakdown of organic nitrogen and phosphatase which facilitates breakdown of organic phosphate. DOM fluorescence spectroscopy enables rapid quantification of different organic matter fluorophores (e.g., amino acid-, humic acid-, and fulvic acid-like). Excitation-emission matrices (EEMs) of DOM fluorescence can be coupled with parallel factor analysis (PARAFAC) for detailed quantitative analysis. Samples were collected quarterly from May 2011 to July 2012 and characterized using both EEA and EEM. We show that significant differences in stream EEA are explained by DOM fluorescence, land cover, and inorganic nutrient inputs. Specifically, urbanized sites were characterized by relatively low ortho-phosphate concentrations, high inorganic nitrogen concentrations, high phosphatase EEA, and greater amino acid-like DOM fluorescence. Aminopeptidase activity increased with increasing amino acid-like DOM fluorescence (i.e., a labile form of DOM for microbes) in forested streams. By contrast aminopeptidase activity did not respond to increasing amino acid-like fluorescence in urbanized streams. This points to a difference in limitation in inorganic nutrients between stream types. Thus, we hypothesize that stream microbial communities

  12. Explaining geographic gradients in winter selection of landscapes by boreal caribou with implications under global changes in Eastern Canada.

    Directory of Open Access Journals (Sweden)

    Julien Beguin

    Full Text Available Many animal species exhibit broad-scale latitudinal or longitudinal gradients in their response to biotic and abiotic components of their habitat. Although knowing the underlying mechanism of these patterns can be critical to the development of sound measures for the preservation or recovery of endangered species, few studies have yet identified which processes drive the existence of geographical gradients in habitat selection. Using extensive spatial data of broad latitudinal and longitudinal extent, we tested three hypotheses that could explain the presence of geographical gradients in landscape selection of the endangered boreal woodland caribou (Rangifer tarandus caribou during winter in Eastern Canadian boreal forests: 1 climate-driven selection, which postulates that geographic gradients are surrogates for climatic gradients; 2 road-driven selection, which proposes that boreal caribou adjust their selection for certain habitat classes as a function of proximity to roads; and 3 an additive effect of both roads and climate. Our data strongly supported road-driven selection over climate influences. Thus, direct human alteration of landscapes drives boreal caribou distribution and should likely remain so until the climate changes sufficiently from present conditions. Boreal caribou avoided logged areas two-fold more strongly than burnt areas. Limiting the spread of road networks and accounting for the uneven impact of logging compared to wildfire should therefore be integral parts of any habitat management plan and conservation measures within the range of the endangered boreal caribou. The use of hierarchical spatial models allowed us to explore the distribution of spatially-structured errors in our models, which in turn provided valuable insights for generating alternative hypotheses about processes responsible for boreal caribou distribution.

  13. Explaining the changing institutional organisation of Dutch farms: the role of farmer's attitudes, advisory network and structural factors

    NARCIS (Netherlands)

    Jongeneel, R.A.; Polman, N.B.P.; Slangen, L.H.G.

    2005-01-01

    Although the family farm remains the dominant organisational form for farms there are changes in the legal mode of organisation. Applying the new institutional economics and economic organisation theory the different organisation modes are explained, mainly in terms of control and income rights. Imp

  14. Explaining policy change: the impact of the media, public opinion and political violence on urban budgets in England

    OpenAIRE

    Peter John

    2006-01-01

    This paper seeks to explain national government allocations of urban budgets in England, which changed dramatically over the 1966 to 2003 period. The paper sets out three perspectives on major policy change: partisan shifts, external shocks, and media-agenda punctuations, which link respectively to the literatures on the policy-opinion link, the impact of political violence on welfare policy outputs, and on the media and agenda-setting. After discussing descriptive statistics, the analysis us...

  15. Living in the tide of change: Explaining Japanese subjective health from the socio-demographic

    OpenAIRE

    Hidefumi eHitokoto; Junko eTanaka-Matsumi

    2014-01-01

    Today, countries around the world are caught in the tide of change towards Gesellshaft, or individualistic socio-demographic condition. Recent investigations in Japan have suggested negative impacts of change on emotional and motivational aspects of the Japanese self (Norasakkunkit, Uchida, and Toivonen, 2012; Ogihara and Uchida, 2014). Building on previous findings, in Study 1, we measured socio-demographic change towards individualistic societal condition during 1990 to 2010—two decades mar...

  16. Is the association of breastfeeding with child obesity explained by infant weight change?

    NARCIS (Netherlands)

    L. van Rossem (Lenie); E.M. Taveras (Elsie M.); M.W. Gillman (Matthew W.); K.P. Kleinman (Ken P.); S.L. Rifas-Shiman (Sheryl L.); H. Raat (Hein); E. Oken (Emily)

    2011-01-01

    textabstractObjective. Breastfeeding and infant weight change are both associated with adiposity. We examined the extent to which infant weight change mediates the association between breastfeeding and adiposity at age 3 years. Methods. We studied 884 children in a prospective cohort study. We deter

  17. Living in the tide of change: Explaining Japanese subjective health from the socio-demographic

    Directory of Open Access Journals (Sweden)

    Hidefumi eHitokoto

    2014-10-01

    Full Text Available Today, countries around the world are caught in the tide of change towards Gesellshaft, or individualistic socio-demographic condition. Recent investigations in Japan have suggested negative impacts of change on emotional and motivational aspects of the Japanese self (Norasakkunkit, Uchida, and Toivonen, 2012; Ogihara and Uchida, 2014. Building on previous findings, in Study 1, we measured socio-demographic change towards individualistic societal condition during 1990 to 2010—two decades marked by great economic recession—at the levels of prefecture and city using archival data. In Study 2, we tested whether Japanese adults’ general health, satisfaction with life, self-esteem, and perceived social support were negatively predicted by the change using social survey. Results of hierarchical linear modeling showed small but unique negative effects of the change on several health measures, suggesting that this change had an impact on health, above and beyond individual personality traits and demographics. Additionally, interdependent happiness, the type of cultural happiness grounded in interdependence of the self (Hitokoto and Uchida, 2014, showed an independent positive relationship with all aspects of health examined. Implications for health studies in changing socio-demographic condition are discussed in the context of Japanese society after economic crisis.

  18. Do Historical Changes in Parent?Child Relationships Explain Increases in Youth Conduct Problems?

    OpenAIRE

    Scott, Jacqueline; Gardner, Frances; Stephan, Collishaw; Maughan, Barbara; Pickles, Andrew

    2011-01-01

    The coincidence of historical trends in youth antisocial behavior and change in family demographics has led to speculation of a causal link, possibly mediated by declining quality of parenting and parent?child relationships. No study to date has directly assessed whether and how parenting and parent?child relationships have changed. Two national samples of English adolescents aged 16?17 years in 1986 (N=4,524 adolescents, 7,120 parents) and 2006 (N=716 adolescents, 734 parents) were compared ...

  19. With the alpha-cluster model to explain the change of separating energy

    Institute of Scientific and Technical Information of China (English)

    ZHANG Lun-Dong; GUO Jian-You; FANG Xiang-Zheng

    2009-01-01

    It was supposed that, the nucleus was composed of α -cluster, pn-pair, and nn-pair. The reciprocity of the α-cluster, pn-pair, and nn-pair caused the regular change of the separating energy to separate the nn-pair in the exotic nuclei. The regular change was that the separating energy was high behind low to separate the nn-pair in the light and exotic nuclei. This phenomenon must had more profound physical meaning.

  20. "Sharing is Caring": Corporate social responsibility awareness explaining the relationship of information flow with affective commitment

    NARCIS (Netherlands)

    C.L. ter Hoeven; J.W.M. Verhoeven

    2013-01-01

    Purpose - The effects of corporate social responsibility (CSR) communication on external stakeholders' perceptions and behaviours have been studied extensively; however, researchers have largely overlooked the effects of CSR communication on internal stakeholders. This study seeks to propose that, b

  1. Different damping responses explain vertical endpoint error differences between visual conditions.

    Science.gov (United States)

    Hondzinski, Jan M; Soebbing, Chelsea M; French, Allyson E; Winges, Sara A

    2016-06-01

    Upright people making goal-directed movements in dark environments often vertically undershoot remembered target locations when compared to performances in illuminated environments. In this study, we wanted to determine whether influences of the gravitational pull and/or type of muscle activation could explain differences in vertical endpoint precision between movements to visually remembered target locations with and without allocentric cues available. We also used a simple damping model for movement trajectories to describe potential differences in behavior between visual conditions. Subjects performed straight arm pointing movements to REAL target locations or remembered target locations in darkness (DARK) or normal room lighting (LIGHT). Performances were made from UPRIGHT and INVERTED (upside down) body orientations. Starting arm position (UP by the ear; DOWN on the thigh) also varied so that eccentric or concentric muscle contractions for arm flexion or extension movements occurred primarily along the earth-fixed vertical either with or against the gravitational pull. Effects of visual condition (LIGHT, DARK), body orientation (UPRIGHT, INVERTED), starting arm position (UP, DOWN), and target level (Near, Middle, Far) on elevation endpoint errors revealed that subject's errors in the DARK were more negative than those in the LIGHT. Errors correlated well with movement displacement to reveal the common vertical undershooting bias in darkness exacerbated by inverting the body or requiring greater movement excursions. Although influences of gravitational pull and muscle activation type could not explain differences between visual conditions, modeling revealed critically damped behavior in the DARK and under-damped behavior in the LIGHT to indicate muscle energy dissipation without vision. PMID:26821319

  2. Responsible Reaction To Climate Change

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    China calls for turning UNFCCC provisions into concrete actions Never before has climate change been as prominent on the public agenda as it is today.Its rele- vance was highlighted once again when more than 10,000 delegates from over 180 countries flocked to Bali early this month to discuss the topic.Environment officials as well as representatives from intergovernmental and nongovernmental organizations gath- ered on the Indonesian island on December 3-14 for the UN Climate Change Conference.

  3. Explaining the relation between job insecurity and employee outcomes during organizational change: A multiple group comparison

    NARCIS (Netherlands)

    Schumacher, Désirée; Schreurs, Bert; van Emmerik, Hetty; de Witte, Hans

    2016-01-01

    We develop and test a mediation model linking job insecurity to affective commitment and psychosomatic complaints via two distinct theoretical mechanisms: fairness and energy depletion. Analyses were based on 6,268 Belgian bank employees facing organizational change. Results from structural equation

  4. 'Horrors of Holland': Explaining attitude change towards euthanasia and homosexuals in the Netherlands, 1970-1998

    NARCIS (Netherlands)

    Jaspers, E.; Lubbers, M.; Graaf, N.D. de

    2007-01-01

    In this article, we investigate changes in public opinion in the Netherlands toward two controversial issues: homosexuals and euthanasia. We find that a rapid decrease in opposition to both issues in the seventies and early eighties was followed by a period of a stable minority opposition. We identi

  5. Occupational Mobility in Members of the Labor Force: Explaining the Willingness to Change Occupations

    Science.gov (United States)

    Otto, Kathleen; Dette-Hagenmeyer, Dorothea E.; Dalbert, Claudia

    2010-01-01

    It has become a commonplace for people to move from one occupation to another during their career. The authors propose that work-related attitudes and person-related characteristics should be considered when examining the willingness to change occupations (WCOs). Consistent with our hypotheses, we found that high levels of work satisfaction,…

  6. Explaining Employees' Evaluations of Organizational Change with the Job-Demands Resources Model

    Science.gov (United States)

    van Emmerik, I. J. Hetty; Bakker, Arnold B.; Euwema, Martin C.

    2009-01-01

    Purpose: Departing from the Job Demands-Resources (JD-R) model, the paper examined the relationship between job demands and resources on the one hand, and employees' evaluations of organizational change on the other hand. Design/methodology/approach: Participants were 818 faculty members within six faculties of a Dutch university. Data were…

  7. Explaining Responses in Danish and Irish Banking to the Financial Crisis

    DEFF Research Database (Denmark)

    Kluth, Michael Friederich; Lynggaard, Kennet

    responsibility for sector losses and only later defined terms for industry contributions. In Denmark a negotiated settlement from the onset passed most of the risk associated to banking failures collectively to the sector. Bearing in mind that vital design decisions regarding national schemes were made...

  8. The association between parenting behavior and somatization in adolescents explained by physiological responses in adolescents

    NARCIS (Netherlands)

    Rousseau, Sofie; Grietens, Hans; Vanderfaeillie, Johan; Hoppenbrouwers, Karel; Wiersema, Jan R.; Baetens, Imke; Vos, Pieter; Van Leeuwen, Karla

    2014-01-01

    Introduction: This study adds to the knowledge on somatization in adolescents by exploring its relation with parenting behavior and the mediating/moderating role of physiological responses in adolescents to parenting behavior. Method: Eighteen adolescents with high and 18 adolescents with low somati

  9. Optimal feedback control successfully explains changes in neural modulations during experiments with brain-machine interfaces

    Directory of Open Access Journals (Sweden)

    Miriam eZacksenhouse

    2015-05-01

    Full Text Available Recent experiments with brain-machine-interfaces (BMIs indicate that the extent of neural modulations increased abruptly upon starting to operate the interface, and especially after the monkey stopped moving its hand. In contrast, neural modulations that are correlated with the kinematics of the movement remained relatively unchanged. Here we demonstrate that similar changes are produced by simulated neurons that encode the relevant signals generated by an optimal feedback controller during simulated BMI experiments. The optimal feedback controller relies on state estimation that integrates both visual and proprioceptive feedback with prior estimations from an internal model. The processing required for optimal state estimation and control were conducted in the state-space, and neural recording was simulated by modeling two populations of neurons that encode either only the estimated state or also the control signal. Spike counts were generated as realizations of doubly stochastic Poisson processes with linear tuning curves. The model successfully reconstructs the main features of the kinematics and neural activity during regular reaching movements. Most importantly, the activity of the simulated neurons successfully reproduces the observed changes in neural modulations upon switching to brain control. Further theoretical analysis and simulations indicate that increasing the process noise during normal reaching movement results in similar changes in neural modulations. Thus we conclude that the observed changes in neural modulations during BMI experiments can be attributed to increasing process noise associated with the imperfect BMI filter, and, more directly, to the resulting increase in the variance of the encoded signals associated with state estimation and the required control signal.

  10. Optimal feedback control successfully explains changes in neural modulations during experiments with brain-machine interfaces.

    Science.gov (United States)

    Benyamini, Miri; Zacksenhouse, Miriam

    2015-01-01

    Recent experiments with brain-machine-interfaces (BMIs) indicate that the extent of neural modulations increased abruptly upon starting to operate the interface, and especially after the monkey stopped moving its hand. In contrast, neural modulations that are correlated with the kinematics of the movement remained relatively unchanged. Here we demonstrate that similar changes are produced by simulated neurons that encode the relevant signals generated by an optimal feedback controller during simulated BMI experiments. The optimal feedback controller relies on state estimation that integrates both visual and proprioceptive feedback with prior estimations from an internal model. The processing required for optimal state estimation and control were conducted in the state-space, and neural recording was simulated by modeling two populations of neurons that encode either only the estimated state or also the control signal. Spike counts were generated as realizations of doubly stochastic Poisson processes with linear tuning curves. The model successfully reconstructs the main features of the kinematics and neural activity during regular reaching movements. Most importantly, the activity of the simulated neurons successfully reproduces the observed changes in neural modulations upon switching to brain control. Further theoretical analysis and simulations indicate that increasing the process noise during normal reaching movement results in similar changes in neural modulations. Thus, we conclude that the observed changes in neural modulations during BMI experiments can be attributed to increasing process noise associated with the imperfect BMI filter, and, more directly, to the resulting increase in the variance of the encoded signals associated with state estimation and the required control signal.

  11. THE RESOURCE-BASED VIEW OR STAKEHOLDER THEORY: WHICH BETTER EXPLAINS THE RELATIONSHIP BETWEEN CORPORATE SOCIAL RESPONSIBILITY AND FINANCIAL PERFORMANCE?

    OpenAIRE

    Agata Adamska; Tomasz j. Dabrowski; Anna Grygiel-Tomaszewska

    2016-01-01

    Stakeholder behavior and reputation are held to be the two main factors explaining the positive correlation between corporate social responsibility and financial performance. To date, however, researchers have not determined which of these factors is of greater significance. The results of this study indicate that the relative effects of stakeholder behavior and reputation are affected by market conditions. During a crisis, the former factor plays a greater role, while the latter becomes m...

  12. Macroecology of Environmental Change Response

    DEFF Research Database (Denmark)

    Jørgensen, Peter Søgaard

    for co-existence, minimizing local extinctions of coldadapted species during global warming. Effects on biodiversity of human-mediated environmental change feed back to human society by challenging food production, human health and environmental management. These challenges are caused by declines...... with climate change being proposed as one of the causes. The chapter investigates the evidence for recent increases in tropical precipitation and primary productivity to cause a recovery in migrant populations. It presents novel evidence for two dichotomies in the effect of such “re-greening”. Over yearly time...... in species that human societies depend on and due to rapid evolution in species that are considered pests and pathogens. Chapter VIII takes a step back and provides a multidisciplinary review of how biological knowledge of environmental change effects can be turned into solutions to minimize current global...

  13. Ecological response to global climatic change

    Science.gov (United States)

    Malanson, G.P.; Butler, D.R.; Walsh, S. J.

    2004-01-01

    Climate change and ecological change go hand in hand. Because we value our ecological environment, any change has the potential to be a problem. Geographers have been drawn to this challenge, and have been successful in addressing it, because the primary ecological response to climate changes in the past — the waxing and waning of the great ice sheets over the past 2 million years – was the changing geographic range of the biota. Plants and animals changed their location. Geographers have been deeply involved in documenting the changing biota of the past, and today we are called upon to help assess the possible responses to ongoing and future climatic change and, thus, their impacts. Assessing the potential responses is important for policy makers to judge the outcomes of action or inaction and also sets the stage for preparation for and mitigation of change.

  14. Changes in Habitat Structure May Explain Decrease in Reintroduced Mohor Gazelle Population in the Guembeul Fauna Reserve, Senegal

    OpenAIRE

    Eulalia Moreno; Abibou Sane; Jesús Benzal; Belén Ibáñez; Joaquín Sanz-Zuasti; Gerardo Espeso

    2012-01-01

    Simple Summary The reintroduction of plants and animals to the wild is an important technique to save endangered species from extinction. To perform post release monitoring is crucial to evaluate reintroduction outcomes. A Mohor gazelle reintroduction programme took place in Senegal in 1984. We attempt to explain why the size of the reintroduced gazelle population has diminished in recent years. We suggest that changes in habitat structure occurred over time and have very likely reduced the a...

  15. Sex-different response in growth traits to resource heterogeneity explains male-biased sex ratio

    Science.gov (United States)

    Matsushita, Michinari; Takao, Mikako; Makita, Akifumi

    2016-08-01

    In dioecious plants, differences in growth traits between sexes in a response to micro-environmental heterogeneity may affect sex ratio bias and spatial distributions. Here, we examined sex ratios, stem growth traits and spatial distribution patterns in the dioecious clonal shrub Aucuba japonica var. borealis, in stands with varying light intensities. We found that male stems were significantly more decumbent (lower height/length ratio) but female stems were upright (higher height/length ratio). Moreover, we found sex-different response in stem density (no. of stems per unit area) along a light intensity gradient; in males the stem density increased with increases in canopy openness, but not in females. The higher sensitivity of males in increasing stem density to light intensity correlated with male-biased sex ratio; fine-scale sex ratio was strongly male-biased as canopy openness increased. There were also differences between sexes in spatial distributions of stems. Spatial segregation of sexes and male patches occupying larger areas than female patches might result from vigorous growth of males under well-lit environments. In summary, females and males showed different growth responses to environmental variation, and this seemed to be one of possible causes for the sex-differential spatial distributions and locally biased sex ratios.

  16. Explaining stability and changes in school effectiveness by looking at changes in the functioning of school factors

    NARCIS (Netherlands)

    Creemers, Bert P. M.; Kyriakides, Leonidas

    2010-01-01

    This paper investigates the extent to which changes in the effectiveness status of schools can be related to changes in the functioning of school factors included in the dynamic model of educational effectiveness. The methods of a follow-up study were identical to those of a study conducted 4 years

  17. Human response to global change

    International Nuclear Information System (INIS)

    Alertness of the global climate and environment change triggered by the effects of the economy of waste of industrial modern society has been raised to governments and populations. World-wide agreements and protocols have been established; they will be improved for action in two major issues: limitation (elimination of CFC's use, reductions of CO2 emissions, increasing energy efficiency, etc.) and adaptation (socio economic impacts, human behaviour, enhancement of predictive models, etc.)

  18. Temporal changes of spatial soil moisture patterns: controlling factors explained with a multidisciplinary approach

    Science.gov (United States)

    Martini, Edoardo; Wollschläger, Ute; Kögler, Simon; Behrens, Thorsten; Dietrich, Peter; Reinstorf, Frido; Schmidt, Karsten; Weiler, Markus; Werban, Ulrike; Zacharias, Steffen

    2016-04-01

    different hydrologic conditions and the factors controlling the temporal variability of the ECa-soil moisture relationship. The approach provided valuable insight into the time-varying contribution of local and nonlocal factors to the characteristic spatial patterns of soil moisture and the transition mechanisms. The spatial organization of soil moisture was controlled by different processes in different soil horizons, and the topsoil's moisture did not mirror processes that take place within the soil profile. Results show that, for the Schäfertal hillslope site which is presumed to be representative for non-intensively managed soils with moderate clay content, local soil properties (e.g., soil texture and porosity) are the major control on the spatial pattern of ECa. In contrast, the ECa-soil moisture relationship is small and varies over time indicating that ECa is not a good proxy for soil moisture estimation at the investigated site.Occasionally observed stronger correlations between ECa and soil moisture may be explained by background dependencies of ECa to other state variables such as pore water electrical conductivity. The results will help to improve conceptual understanding for hydrological model studies at similar or smaller scales, and to transfer observation concepts and process understanding to larger or less instrumented sites, as well as to constrain the use of EMI-based ECa data for hydrological applications.

  19. Explaining technical change in a small country the Finnish national innovation system

    CERN Document Server

    Vuorinen, Pentti

    1994-01-01

    Technical change is produced by the interaction of a large number of technical, economic, social and institutional factors. One of the starting points is the concept of national innovation systems. The aim of this book is to take Finland as an example illustrating the challenges faced by small countries. The characteristics and performance of the Finnish national innovation system of the last couple of decades are analyzed. The Finnish experience is put in a broader context by comparing it with a few other countries. The development paths possible in the near future are assessed. According to the results, many problems remain despite favourable developments in several technology indicators. The rigidities of the social institutions created during the 1970s and 1980s seem to have become obstacles for economic and technological development. There are fairly large differences between the countries studied, and even between the culturally and historically close Nordic countries. However,Finland and Sweden seem to...

  20. Explaining the Survival of the Swedish Welfare State: Maintaining Political Support Through Incremental Change

    Directory of Open Access Journals (Sweden)

    Andreas Bergh

    2008-09-01

    Full Text Available Despite challenges and doomsday predictions, the Nordic welfare states with high taxes and public expenditure are still with us. This paper describes strategic choices for policy makers of the welfare state and uses the case of Sweden to argue that the high tax welfare state has survived several challenges through a process of incremental change, where the welfare state is modified in order to maintain political support from voters who would otherwise favor cutbacks. This gradual adaptation leads to heterogeneous universality characterized by flexibility, freedom of choice, and financial solutions that involve both public and private funding. While such policies may increase inequality, they play a crucial role in maintaining political support for high taxes and expenditures. Compared to likely counterfactual scenarios, this gradual adaptation may be the political strategy that minimizes inequality in the long run.

  1. Unique responsiveness of angiosperm stomata to elevated CO2 explained by calcium signalling.

    Directory of Open Access Journals (Sweden)

    Timothy J Brodribb

    Full Text Available Angiosperm and conifer tree species respond differently when exposed to elevated CO2, with angiosperms found to dynamically reduce water loss while conifers appear insensitive. Such distinct responses are likely to affect competition between these tree groups as atmospheric CO2 concentration rises. Seeking the mechanism behind this globally important phenomenon we targeted the Ca(2+-dependent signalling pathway, a mediator of stomatal closure in response to elevated CO2, as a possible explanation for the differentiation of stomatal behaviours. Sampling across the diversity of vascular plants including lycophytes, ferns, gymnosperms and angiosperms we show that only angiosperms possess the stomatal behaviour and prerequisite genetic coding, linked to Ca(2+-dependent stomatal signalling. We conclude that the evolution of Ca(2+-dependent stomatal signalling gives angiosperms adaptive benefits in terms of highly efficient water use, but that stomatal sensitivity to high CO2 may penalise angiosperm productivity relative to other plant groups in the current era of soaring atmospheric CO2.

  2. Explaining Large-Scale Policy Change in the Turkish Health Care System: Ideas, Institutions, and Political Actors.

    Science.gov (United States)

    Agartan, Tuba I

    2015-10-01

    Explaining policy change has been one of the major concerns of the health care politics and policy development literature. This article aims to explain the specific dynamics of large-scale reforms introduced within the framework of the Health Transformation Program in Turkey. It argues that confluence of the three streams - problem, policy, and politics - with the exceptional political will of the Justice and Development Party's (JDP) leaders opened up a window of opportunity for a large-scale policy change. The article also underscores the contribution of recent ideational perspectives that help explain "why" political actors in Turkey would focus on health care reform, given that there are a number of issues waiting to be addressed in the policy agenda. Examining how political actors framed problems and policies deepens our understanding of the content of the reform initiatives as well as the construction of the need to reform. The article builds on the insights of both the ideational and institutionalist perspectives when it argues that the interests, aspirations, and fears of the JDP, alongside the peculiar characteristics of the institutional context, have shaped its priorities and determination to carry out this reform initiative.

  3. The Welfare State as Crisis Manager: Explaining the Diversity of Policy Responses to Economic Crisis

    DEFF Research Database (Denmark)

    Starke, Peter; Kaasch, Alexandra; van Hooren, Franca

    Written during an ongoing period of global economic crisis, The Welfare State as a Crisis Manager examines the practice and potential of using social policy to cope with crises. Through an in-depth analysis of social policy reactions in the wake of international economic shocks in four different...... welfare states, over a 40-year period, the book reveals the ways in which expansion and retrenchment are shaped by domestic politics and existing welfare state institutions. Moreover, the study addresses the kind of policy change triggered by economic crisis. In contrast to conventional wisdom...... and previous scholarship, reactions tend to be characterised by incrementalism and 'crisis routines' rather than fundamental deviations from earlier policy patterns. For the first time, the study of domestic political dynamics following crisis is systematically embedded in the transnational policy debate...

  4. Morphological Responses Explain Tolerance of the Bamboo Yushania microphylla to Grazing

    Directory of Open Access Journals (Sweden)

    Kesang Wangchuk

    2014-01-01

    Full Text Available Mechanisms of tolerance of the bamboo Y. microphylla to ungulate herbivory were investigated by measuring above- and belowground morphogenetic traits and biomass allocation patterns of the bamboo Y. microphylla under grazed and ungrazed conditions in a Himalayan mixed conifer forest. Data were collected from 5 populations consisting of 10 ramets each in adjacent grazed and ungrazed plots. Compared with ungrazed ramets, the aboveground morphological modifications of grazed ramets were higher culm density, shorter and thinner culms, shorter internode, and shorter top leaf. The belowground morphological modifications for the grazed ramets were thinner rhizomes, lower rhizome biomass and dry matter, more nodes, and shorter internodes. Despite the lower biomass and dry matter, the root-to-shoot ratio was higher for grazed ramets. Results suggest that Y. microphylla subjected to herbivory shows aboveground overcompensation in terms of densification at the cost of belowground biomass, but at the same time maintains a higher proportion of belowground reserves, as compared to ungrazed conditions. These responses provide adequate evidence to conclude that Y. microphylla tolerates ungulate herbivory through above- and belowground morphological modifications.

  5. Formation of S0 galaxies through mergers: Explaining angular momentum and concentration change from spirals to S0s

    CERN Document Server

    Querejeta, Miguel; Tapia, Trinidad; Borlaff, Alejandro; van de Ven, Glenn; Lyubenova, Mariya; Martig, Marie; Falcón-Barroso, Jesús; Méndez-Abreu, Jairo

    2015-01-01

    The CALIFA team has recently found that the stellar angular momentum and concentration of late-type spiral galaxies are incompatible with those of lenticular galaxies (S0s), concluding that fading alone cannot satisfactorily explain the evolution from spirals into S0s. Here we explore whether major mergers can provide an alternative way to transform spirals into S0s by analysing the spiral-spiral major mergers from the GalMer database that lead to realistic, relaxed S0-like galaxies. We find that the change in stellar angular momentum and concentration can explain the differences in the $\\lambda_\\mathrm{Re}$--$R_{90}/R_{50}$ plane found by the CALIFA team. Major mergers thus offer a feasible explanation for the transformation of spirals into S0s.

  6. Streaming driven by sessile microbubbles: Explaining flow patterns and frequency response

    Science.gov (United States)

    Rallabandi, Bhargav; Wang, Cheng; Guo, Lin; Hilgenfeldt, Sascha

    2013-11-01

    Ultrasound excitation of bubbles drives powerful steady streaming flows which have found widespread applications in microfluidics, where bubbles are typically of semicircular cross section and attached to walls of the device (sessile). While bubble-driven streaming in bulk fluid is well understood, this practically relevant case presents additional complexity introduced by the wall and contact lines. We develop an asymptotic theory that takes into account the presence of the wall as well as the oscillation dynamics of the bubble, providing a complete description of the streaming flow as a function only of the driving frequency, the bubble size, and the physical properties of the fluid. We show that the coupling between different bubble oscillation modes sustains the experimentally observed streaming flow vortex pattern over a broad range of frequencies, greatly exceeding the widths of individual mode resonances. Above a threshold frequency, we predict, and observe in experiment, reversal of the flow direction. Our analytical theory can be used to guide the design of microfluidic devices, both in situations where robust flow patterns insensitive to parameter changes are desired (e.g. lab-on-a-chip sorters), and in cases where intentional modulation of the flow field appearance is key (e.g. efficient mixers). Current address: Department of Mechanical and Aerospace Engineering, Missouri University of Science and Technology.

  7. Responses to Change Helping People Make Transitions

    CERN Document Server

    (CCL), Center for Creative Leadership

    2011-01-01

    The ongoing state of many organizations is one of change. People who experience major change tend to exhibit one of four patterns of response: entrenched, overwhelmed, poser, or learner. As a leader, you need to understand the patterns of response that people express and to customize intervention strategies to help them make the transition. People can pass through a given response stage and move to one that is more effective--especially if you provide timely intervention and support. This guidebook will help you understand how people, including yourself, are responding to change and what you c

  8. Temperature and pressure effects on GFP mutants: explaining spectral changes by molecular dynamics simulations and TD-DFT calculations.

    Science.gov (United States)

    Jacchetti, Emanuela; Gabellieri, Edi; Cioni, Patrizia; Bizzarri, Ranieri; Nifosì, Riccardo

    2016-05-14

    By combining spectroscopic measurements under high pressure with molecular dynamics simulations and quantum mechanics calculations we investigate how sub-angstrom structural perturbations are able to tune protein function. We monitored the variations in fluorescence output of two green fluorescent protein mutants (termed Mut2 and Mut2Y, the latter containing the key T203Y mutation) subjected to pressures up to 600 MPa, at various temperatures in the 280-320 K range. By performing 150 ns molecular dynamics simulations of the protein structures at various pressures, we evidenced subtle changes in conformation and dynamics around the light-absorbing chromophore. Such changes explain the measured spectral tuning in the case of the sizable 120 cm(-1) red-shift observed for pressurized Mut2Y, but absent in Mut2. Previous work [Barstow et al., Proc. Natl. Acad. Sci. U. S. A., 2008, 105, 13362] on pressure effects on GFP also involved a T203Y mutant. On the basis of cryocooling X-ray crystallography, the pressure-induced fluorescence blue shift at low temperature (77 K) was attributed to key changes in relative conformation of the chromophore and Tyr203 phenol ring. At room temperature, however, a red shift was observed at high pressure, analogous to the one we observe in Mut2Y. Our investigation of structural variations in compressed Mut2Y also explains their result, bridging the gap between low-temperature and room-temperature high-pressure effects. PMID:27102429

  9. Dopamine-mediated learning and switching in cortico-striatal circuit explain behavioral changes in reinforcement learning.

    Directory of Open Access Journals (Sweden)

    Simon eHong

    2011-03-01

    Full Text Available The basal ganglia (BG are thought to play a crucial role in reinforcement learning. Central to the learning mechanism are dopamine D1 and D2 receptors located in the cortico-striatal synapses. However, it is still unclear how this dopamine-mediated synaptic plasticity is deployed and coordinated during reward-contingent behavioral changes. Here we propose a computational model of reinforcement learning that uses different thresholds of D1- and D2-mediated synaptic plasticity which are antagonized by dopamine-independent synaptic plasticity. A phasic increase in dopamine release caused by a larger-than-expected reward induces long-term potentiation (LTP in the direct pathway, whereas a phasic decrease in dopamine release caused by a smaller-than-expected reward induces a cessation of long-term depression (LTD, leading to LTP in the indirect pathway. This learning mechanism can explain the robust behavioral adaptation observed in a location-reward-value-association task where the animal makes shorter latency saccades to rewarding locations. The changes in saccade latency become quicker as the monkey becomes more experienced. This behavior can be explained by a switching mechanism which activates the cortico-striatal circuit selectively. Our model can also simulate the effects of D1 and D2 receptor blockade, and behavioral changes in Parkinson’s disease.

  10. Changing Families, Changing Responsibilities: Family Obligations Following Divorce and Remarriage.

    Science.gov (United States)

    Ganong, Lawrence H.; Coleman, Marilyn

    The high incidence of divorce and remarriage means that the structure of American families is changing. Drawing on 13 studies that explore intergenerational obligations, this book discusses the responsibilities of family members to one another after divorce and remarriage. Chapter 1, "Who Is Responsible for Dependent Family Members?," presents an…

  11. Developmental change in social responsibility during adolescence: An ecological perspective.

    Science.gov (United States)

    Wray-Lake, Laura; Syvertsen, Amy K; Flanagan, Constance A

    2016-01-01

    Social responsibility can be defined as a set of prosocial values representing personal commitments to contribute to community and society. Little is known about developmental change-and predictors of that change-in social responsibility during adolescence. The present study used an accelerated longitudinal research design to investigate the developmental trajectory of social responsibility values and ecological assets across family, school, community, and peer settings that predict these values. Data come from a 3-year study of 3,683 U.S. adolescents enrolled in upper-level elementary, middle, and high schools in rural, semiurban, and urban communities. Social responsibility values significantly decreased from age 9 to 16 before leveling off in later adolescence. Family compassion messages and democratic climate, school solidarity, community connectedness, and trusted friendship, positively predicted within-person change in adolescents' social responsibility values. These findings held after accounting for other individual-level and demographic factors and provide support for the role of ecological assets in adolescents' social responsibility development. In addition, fair society beliefs and volunteer experience had positive between- and within-person associations with social responsibility values. The manuscript discusses theoretical and practical implications of the conclusion that declines in ecological assets may partly explain age-related declines in social responsibility values. (PsycINFO Database Record

  12. Land-atmosphere coupling explains the link between pan evaporation and actual evapotranspiration trends in a changing climate

    NARCIS (Netherlands)

    Heerwaarden, van C.C.; Vilà-Guerau de Arellano, J.; Teuling, A.J.

    2010-01-01

    Decreasing trends in pan evaporation are widely observed across the world as a response of the climate system to changes in temperature, precipitation, incoming radiation and wind speed. Nevertheless, we only partially understand how trends in actual evapotranspiration are linked to those trends. He

  13. The response of glaciers to climate change

    NARCIS (Netherlands)

    Klok, Elisabeth Jantina

    2003-01-01

    The research described in this thesis addresses two aspects of the response of glaciers to climate change. The first aspect deals with the physical processes that govern the interaction between glaciers and climate change and was treated by (1) studying the spatial and temporal variation of the glac

  14. Modeling crop responses to environmental change

    Science.gov (United States)

    Rosenzweig, Cynthia

    1993-01-01

    Potential biophysical responses of crops to climate change are studied focusing on the primary environmental variables which define the limits to agricultural crop growth and production, and the principal methods for predicting climate change impacts on crop geography and production. It is concluded that the principal uncertainties in the prediction of the impacts of climate change on agriculture reside in the contribution of the direct effects of increasing CO2, in potential changes inclimate variability, and the effects of adjustments mechanisms in the context of climatic changes.

  15. Climate Change and Corporate Environmental Responsibility

    OpenAIRE

    Dewan Mahboob HOSSAIN; Chowdhury, M. Jahangir Alam

    2012-01-01

    Climate change, as an international environmental issue, is getting a lot of attention. The negative effects of climate change have become one of the most talked about issues among Governments, scientists, environmentalists and others. It is said that business activities are affecting the climate negatively. In order to minimize the negative effects of climate change, the activities of the businesses should be controlled and encouraged to perform in a socially responsible manner. The article ...

  16. Monitoring adaptive genetic responses to environmental change

    DEFF Research Database (Denmark)

    Hansen, M.M.; Olivieri, I.; Waller, D.M.;

    2012-01-01

    to use genetic monitoring to study adaptive responses via repeated analysis of the same populations over time, distinguishing between phenotypic and molecular genetics approaches. After describing monitoring designs, we develop explicit criteria for demonstrating adaptive responses, which include testing...... for selection and establishing clear links between genetic and environmental change. We then review a few exemplary studies that explore adaptive responses to climate change in Drosophila, selective responses to hunting and fishing, and contemporary evolution in Daphnia using resurrected resting eggs. We......% of the studies based on phenotypic variation did not test for selection as opposed to drift. These shortcomings can be addressed via improved experimental designs and statistical testing. We foresee monitoring of adaptive responses as a future valuable tool in conservation biology, for identifying populations...

  17. Sedimentary response to ocean gateway circulation changes

    Science.gov (United States)

    Heinze, Christoph; Crowley, Thomas J.

    1997-12-01

    Previous modeling studies suggested that changes in ocean gateways may have exerted a dramatic influence on the ocean circulation. In this pilot study we extend those results to examining the potential ramifications of circulation changes on the sedimentary record. A version of the Hamburg carbon cycle/sediment model is used in these sensitivity experiments. Results indicate that internal reorganization of the ocean circulation can potentially cause very large regional changes in lysocline depth (1500-3000 m) and opal deposition. These shifts are sometimes comparable in magnitude to those imposed by changes in external forcing (e.g., climate, sea level, and weathering). Comparisons of the model response with the geologic record indicate some significant levels of first-order agreement. This exercise suggests that opportunities now exist for physically based modeling of past sediment responses to circulation and climate changes.

  18. THE RESOURCE-BASED VIEW OR STAKEHOLDER THEORY: WHICH BETTER EXPLAINS THE RELATIONSHIP BETWEEN CORPORATE SOCIAL RESPONSIBILITY AND FINANCIAL PERFORMANCE?

    Directory of Open Access Journals (Sweden)

    Agata Adamska

    2016-04-01

    Full Text Available Stakeholder behavior and reputation are held to be the two main factors explaining the positive correlation between corporate social responsibility and financial performance. To date, however, researchers have not determined which of these factors is of greater significance. The results of this study indicate that the relative effects of stakeholder behavior and reputation are affected by market conditions. During a crisis, the former factor plays a greater role, while the latter becomes more prominent during the period of market recovery in the wake of a crisis. These findings have important practical ramifications as they provide guidance to companies on how to allocate their CSR budgets depending on the state of the economy to maximize their effect on the bottom line.

  19. Do changes in lymph node status distribution explain trends in survival of breast cancer patients in Denmark?

    DEFF Research Database (Denmark)

    Rostgaard, Klaus; Vaeth, Michael; Rootzén, Helle;

    2006-01-01

    We studied the impact on survival of changes in breast cancer patients' distribution by lymph node status at the time of diagnosis. Our study included breast cancer patients diagnosed from 1978 to 1994 in Denmark, where the treatment schemes for breast cancer patients were fairly stable, and wher...... distribution explained half of the improvement in 5-year relative survival, and seem to be the single most important cause behind the improved survival of breast cancer patients in Denmark.......We studied the impact on survival of changes in breast cancer patients' distribution by lymph node status at the time of diagnosis. Our study included breast cancer patients diagnosed from 1978 to 1994 in Denmark, where the treatment schemes for breast cancer patients were fairly stable, and where...... mammography screening was limited. We measured lymph node status by the proportion of positive lymph nodes of all excised lymph nodes, as assessed by a pathologist. This measure was available for two-thirds of the breast cancer patients. The outcome was 5-year relative survival. Changes in lymph node status...

  20. The high glycemic index diet was an independent predictor to explain changes in agouti-related protein in obese adolescents

    Directory of Open Access Journals (Sweden)

    Bárbara Dal Molin Netto

    2014-02-01

    Full Text Available The high glycemic index diet was an independent predictor to explain changes in agouti-related protein in obese adolescents. Background & Aims: The role of diet glycemic index (GI in the control of orexigenic and anorexigenic factors of the energy balance is still not clear. The present study aimed to assess whether the habitual diet, according to different GI foods, exerts influence on regulation of energy balance markers and the effects of interdisciplinary intervention in obese adolescents. Methods: A total of 55 obese adolescents, aged from 14 to 19 years, were submited to one year of interdisciplinary therapy and were divided in two groups, according to the predominant dietary pattern of food intake: high-GI group (H-GI; n = 29 and moderate/low-GI group (M/L-GI; n = 26. Results: The concentration of orexigenic factor AgRP (p < 0.01, visceral fat (p=0.04 and visceral/subcutaneous ratio (p = 0.03 were higher in the group of H-GI when compared with M/L-GI group. Moreover, the habitual consumption of H-GI foods was an independent predictor to explain changes in AgRP concentrations. After one year of interdisciplinary therapy, the adolescents presented significant reductions in body weight, total body fat (%, visceral and subcutaneous fat and HOMA-IR, as well as a significant increase of fat free mass (%. Conclusions: Our results may suggest that habitual H-GI diet could upregulate orexigenic pathways, contributing to vicious cycle between undesirable diets, deregulates energy balance and predispose to obesity. One the other hand, one year of interdisciplinary therapy can significant improves metabolic profile and central obesity in adolescents.

  1. Changing Faces: Suburban School Response to Demographic Change

    Science.gov (United States)

    Evans, Andrea E.

    2007-01-01

    As minority populations continue to grow, suburban school systems will bear a larger responsibility for educating students of color. Rapid demographic change may mean that students of color could walk into suburban schools ill prepared to address their academic and social needs. The focus of this study was to examine how and why several suburban…

  2. Response disinhibition may be explained as an extinction deficit in an animal model of attention-deficit/hyperactivity disorder (ADHD).

    Science.gov (United States)

    Johansen, Espen Borgå; Sagvolden, Terje

    2004-03-01

    Attention-deficit/hyperactivity disorder (ADHD) is a disorder affecting between 2 and 12% of grade-school children disturbing social, academic, and occupational functioning. Problems related to social adjustment and functioning and/or psychiatric problems will exist in 50-70% of adolescents and young adults diagnosed with ADHD as children. It has been suggested that altered reinforcement and extinction processes may cause the symptoms of ADHD. The present study investigated extinction processes in spontaneously hypertensive rats (SHR), possibly the best-validated animal model of ADHD. Extinction was tested after either a variable interval (VI) or a fixed interval (FI) schedule of reinforcement with and without the presence of a conditioned reinforcer (light in the water cubicle). The results indicate a slower extinction process in the SHR compared to the normal controls, especially during the initial transition from scheduled reinforcement to extinction. Also, more responses were retained in the SHR during the later part of extinction. The extinction deficit in the SHR may be linked to reinforcer unpredictability and the presence of conditioned reinforcers, and may explain response disinhibition seen in children with ADHD. PMID:15129781

  3. Dynamical feedback between circadian clock and sucrose availability explains adaptive response of starch metabolism to various photoperiods

    Directory of Open Access Journals (Sweden)

    Francois Gabriel Feugier

    2013-01-01

    Full Text Available Plants deal with resource management during all their life. During the day they feed on photosynthetic carbon, sucrose, while storing a part into starch for night use. Careful control of carbon partitioning, starch degradation and sucrose export rates is crucial to avoid carbon starvation, insuring optimal growth whatever the photoperiod. Efficient regulation of these key metabolic rates can give an evolutionary advantage to plants. Here we propose a model of adaptive starch metabolism in response to various photoperiods. We assume the three key metabolic rates to be circadian regulated in leaves and that their phases of oscillations are shifted in response to sucrose starvation. We performed gradient descents for various photoperiod conditions to find the corresponding optimal sets of phase shifts that minimize starvation. Results at convergence were all consistent with experimental data: i diurnal starch profile showed linear increase during the day and linear decrease at night; ii shorter photoperiod tended to increase starch synthesis speed while decreasing its degradation speed during the longer night; iii sudden early dusk showed slower starch degradation during the longer night. Profiles that best explained observations corresponded to circadian regulation of all rates. This theoretical study would establish a framework for future research on feedback between starch metabolism and circadian clock as well as plant productivity.

  4. A test of cognitive mediation in a 12-month physical activity workplace intervention: does it explain behaviour change in women?

    Directory of Open Access Journals (Sweden)

    Pickering Michael A

    2010-05-01

    small effect sizes. However, these mediating results were eliminated after adjusting for the multiple statistical tests. Conclusions The intervention did not change these mediators in any substantive way, and show a similar pattern to prior research where interventions generally do not result in a change in mediation of behavior change. It is important to report mediation results in randomized controlled trials whether the findings are null or positive. Future studies may wish to focus on more detailed dose-response issues between mediators and behavior, the inclusion of moderators that could affect individual change, or different mediator constructs at higher levels of measurement specificity. Continued work on innovative and more powerful PA intervention approaches are needed.

  5. Responsiveness and minimal clinically important change

    DEFF Research Database (Denmark)

    Christiansen, David Høyrup; Frost, Poul; Falla, Deborah;

    2015-01-01

    Study Design A prospective cohort study nested in a randomized controlled trial. Objectives To determine and compare responsiveness and minimal clinically important change of the modified Constant score (CS) and the Oxford Shoulder Score (OSS). Background The OSS and the CS are commonly used to a...

  6. Are Rorschach Responses Influenced by Society's Change?

    Science.gov (United States)

    Ames, Louise Bates

    1975-01-01

    Based on the general belief that people "normally" see male figures on Rorschach Card III and females on Card VII; to see the opposite, according to some, would indicate a confusing of sex roles. This study makes two comparisons: age and time changes of individual responses to these cards in different decades. (DEP)

  7. Climate Change: Ethics and Collective Responsibility

    Science.gov (United States)

    Peacock, K.; Brown, M. B.; Mann, M. E.; Lewandowsky, S.

    2014-12-01

    Climate change poses grave risks for societies and people all around the earth. Though details of the risks remain uncertain, they include accelerating sea level rise and ocean acidification, regional drought, floods and heat waves, crop failures and more: dangerous changes are already occurring, while GHG emissions continue to grow, ice melts, water expands, temperature rises, and weather patterns shift. Our roles as individuals and nations in producing the emissions of GHGs responsible for this episode of climate change, and the actions that could be taken to mitigate it, raise difficult ethical questions. When we are responsible for putting others in danger, we have a duty to mitigate that danger. But our sense of responsibility is diluted here: each individual act contributes only minutely to the overall risks, and the links between individual acts and the harms they produce are complex, indirect and involve many other agents. In these circumstances, our sense of personal responsibility is diminished and uncoordinated, individual responses to the risks become ineffective. We propose a view of the ethics of climate change that begins with the tragedy of the commons: Free use of a shared, indispensable resource can lead to catastrophe as the resource is overrun, and the destruction of the commons arises from choices that are individuallyrational, if each person's choice is made independently of others'. Finally, individuals often fail to make ethical choices when the links between individual actions and their negative outcomes are obscure, when individual choices are made separately and privately, and when special interests stand to gain from actions that are generally harmful. Philosophical work in ethics has emphasized the role of ethics in enabling cooperation between individuals and coordinating group responses to problems, while recent work on social rules has modeled them as generalized forbiddings, taught and enforced by 'blocking' behaviours which

  8. Social identity change in response to discrimination.

    Science.gov (United States)

    Perozzo, Cristina; de la Sablonnière, Roxane; Auger, Emilie; Caron-Diotte, Mathieu

    2016-09-01

    This study investigated the conditions under which discrimination can lead to social identity changes among members of a minority group. Both positive and negative relations between perceptions of discrimination and social identity have previously been reported. To explain the conflicting results and understand the complex reality of members of stigmatized groups, we argue that group-based emotions (e.g., group-based dissatisfaction) and ambiguity of discrimination cues (i.e., overt vs. ambiguous) need to be considered. We hypothesized that perceptions of discrimination would play a moderating role between group-based dissatisfaction and social identity change in a context of ambiguous, but not of overt, discrimination. The sample was comprised of 151 Arab Muslims living in the province of Quebec. Participants read fictitious newspaper articles portraying either overt (n = 76) or ambiguous (n = 75) discrimination towards in-group members. Results revealed that for participants in the overt discrimination condition, only group-based dissatisfaction was positively associated with social identity change. In contrast, for the participants in the ambiguous discrimination condition, those who perceived little discrimination and felt low group-based dissatisfaction reported a decrease in social identity. However, those who perceived low group discrimination and felt high group-based dissatisfaction reported a positive social identity change.

  9. Social identity change in response to discrimination.

    Science.gov (United States)

    Perozzo, Cristina; de la Sablonnière, Roxane; Auger, Emilie; Caron-Diotte, Mathieu

    2016-09-01

    This study investigated the conditions under which discrimination can lead to social identity changes among members of a minority group. Both positive and negative relations between perceptions of discrimination and social identity have previously been reported. To explain the conflicting results and understand the complex reality of members of stigmatized groups, we argue that group-based emotions (e.g., group-based dissatisfaction) and ambiguity of discrimination cues (i.e., overt vs. ambiguous) need to be considered. We hypothesized that perceptions of discrimination would play a moderating role between group-based dissatisfaction and social identity change in a context of ambiguous, but not of overt, discrimination. The sample was comprised of 151 Arab Muslims living in the province of Quebec. Participants read fictitious newspaper articles portraying either overt (n = 76) or ambiguous (n = 75) discrimination towards in-group members. Results revealed that for participants in the overt discrimination condition, only group-based dissatisfaction was positively associated with social identity change. In contrast, for the participants in the ambiguous discrimination condition, those who perceived little discrimination and felt low group-based dissatisfaction reported a decrease in social identity. However, those who perceived low group discrimination and felt high group-based dissatisfaction reported a positive social identity change. PMID:27242071

  10. An ethical response to climate change

    Directory of Open Access Journals (Sweden)

    Geoffrey William Lamberton

    2014-09-01

    Full Text Available This paper examines the ethical question of the responsibility of business organisations to respond to climate change. Ethical principles of ‘polluter pays‘, ‘historic culpability’ and ‘equitable distribution of the carbon budget’ are applied to the question of ‘should business respond to climate change’, using rights and utilitarian ethical analyses. An ethical argument is established for business organisations to decarbonise their production and distribution systems rather than delay action. Government policies required to remove barriers which are delaying a widespread and meaningful response by business to humankind’s greatest moral challenge together with the ethical implications are discussed.

  11. Changes in Habitat Structure May Explain Decrease in Reintroduced Mohor Gazelle Population in the Guembeul Fauna Reserve, Senegal

    Directory of Open Access Journals (Sweden)

    Eulalia Moreno

    2012-08-01

    Full Text Available Reintroduction is a widespread method for saving populations of endangered species from extinction. In spite of recent reviews, it is difficult to reach general conclusions about its value as a conservation tool, as authors are reluctant to publish unsuccessful results. The Mohor gazelle is a North African gazelle, extinct in the wild. Eight individuals were reintroduced in Senegal in 1984. The population grew progressively, albeit slowly, during the first 20 years after release, but then declined dramatically, until the population in 2009 was estimated at no more than 13–15 individuals. This study attempts to determine the likelihood of gazelle-habitat relationships to explain why the size of the gazelle population has diminished. Our results show that the Mohor gazelle in Guembeul is found in open habitats with less developed canopy where the grass is shorter, suggesting the possibility that changes in habitat structure have taken place during the time the gazelles have been in the Reserve, reducing the amount of suitable habitat. Reintroduction design usually concentrates on short-term factors that may affect survival of the released animals and their descendants (short-term achievement, while the key factors for assessing its success may be those that affect the long-term evolution of the population.

  12. Photosynthetic Light Responses May Explain Vertical Distribution of Hymenophyllaceae Species in a Temperate Rainforest of Southern Chile

    Science.gov (United States)

    Parra, María José; Acuña, Karina I.; Sierra-Almeida, Angela; Sanfuentes, Camila; Saldaña, Alfredo; Corcuera, Luis J.; Bravo, León A.

    2015-01-01

    Some epiphytic Hymenophyllaceae are restricted to lower parts of the host (1000 μmol photons m-2 s-1). Our aim was to study the photosynthetic light responses of two Hymenophyllaceae species in relation to their contrasting distribution. We determined light tolerance of Hymenoglossum cruentum and Hymenophyllum dentatum by measuring gas exchange, PSI and PSII light energy partitioning, NPQ components, and pigment contents. H. dentatum showed lower maximum photosynthesis rates (Amax) than H. cruentum, but the former species kept its net rates (An) near Amax across a wide light range. In contrast, in the latter one, An declined at PPFDs >60 μmol photons m-2 s-1. H. cruentum, the shadiest plant, showed higher chlorophyll contents than H. dentatum. Differences in energy partitioning at PSI and PSII were consistent with gas exchange results. H. dentatum exhibited a higher light compensation point of the partitioning of absorbed energy between photochemical Y(PSII) and non-photochemical Y(NPQ) processes. Hence, both species allocated energy mainly toward photochemistry instead of heat dissipation at their light saturation points. Above saturation, H. cruentum had higher heat dissipation than H. dentatum. PSI yield (YPSI) remained higher in H. dentatum than H. cruentum in a wider light range. In both species, the main cause of heat dissipation at PSI was a donor side limitation. An early dynamic photo-inhibition of PSII may have caused an over reduction of the Qa+ pool decreasing the efficiency of electron donation to PSI. In H. dentatum, a slight increase in heat dissipation due to acceptor side limitation of PSI was observed above 300 μmol photons m-2s-1. Differences in photosynthetic responses to light suggest that light tolerance and species plasticity could explain their contrasting vertical distribution. PMID:26699612

  13. Cortical Thickness Changes Associated with Photoparoxysmal Response

    DEFF Research Database (Denmark)

    Hanganu, Alexandru; Groppa, Stanislav A; Deuschl, Günther;

    2014-01-01

    Photoparoxysmal response (PPR) is an EEG trait of spike and spike-wave discharges in response to photic stimulation that is closely linked to idiopathic generalized epilepsy (IGE). In our previous studies we showed that PPR is associated with functional alterations in the occipital and frontal...... compared these groups with a group of PPR-negative-healthy-controls (HC, n = 17; 15.3 ± 3.6 years; 6 males). Our results revealed an increase of cortical thickness in the occipital, frontal and parietal cortices bilaterally in PPR-positive-subjects in comparison to HC. Moreover PPR...... the occipital lobe, frontoparietal regions and temporal lobe, which also show functional changes associated with PPR. Patients with epilepsy present changes in the temporal lobe and supplementary motor area....

  14. An ethical response to climate change

    OpenAIRE

    Geoffrey William Lamberton

    2014-01-01

    This paper examines the ethical question of the responsibility of business organisations to respond to climate change. Ethical principles of ‘polluter pays‘, ‘historic culpability’ and ‘equitable distribution of the carbon budget’ are applied to the question of ‘should business respond to climate change’, using rights and utilitarian ethical analyses. An ethical argument is established for business organisations to decarbonise their production and distribution systems rather than delay action...

  15. Changes in Vascular Plant Biodiversity in the Netherlands in the 20th Century Explained by their Climatic and other Environmental Characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Tamis, W.L.M.; Van der Meijden, R.; Udo de Haes, H.A. [Nationaal Herbarium Nederland/Leiden University Branch, P.O. Box 9514, 2300, RA, Leiden (Netherlands); Van ' t Zelfde, M. [Institute of Environmental Sciences, Leiden University, P.O. Box 9518, 2300, RA, Leiden (Netherlands)

    2005-09-01

    In the Netherlands nation-wide databases are available with about 10 million records of occurrences of vascular plant species in the 20th century on a scale of approximately 1 km{sup 2}. These data were analysed with a view to identifying relationships between changes in botanical biodiversity and climatic and other environmental factors. Prior to analysis the data were corrected for several major forms of survey bias. The records were broken down into three periods: 1902-1949, 1975-1984 and 1985-1999. Using multiple regression analysis, differences between successive periods were related to plant functional characteristics as explanatory variables. Between the periods 1902-1949 and 1975-1984 there were small but significant increases in the presence of both thermophilic ('warm') and psychrophilic ('cold') species. However, in the final decades of the 20th century there was a marked increase in thermophilic species only, coinciding with the marked increase in ambient temperature observed during this period, evidence at least of a rapid response of Dutch flora to climate change. Urbanisation was also examined as an alternative explanation for the increase in thermophilic plant species and was found to explain only 50% of the increased presence of such species in the final decades of the 20th century. Besides temperature-related effects, the most important change during the 20th century was a strong decline in oligotrophic and a marked increase in eutrophic plant species.

  16. Regional climate change and national responsibilities

    Science.gov (United States)

    Hansen, James; Sato, Makiko

    2016-03-01

    Global warming over the past several decades is now large enough that regional climate change is emerging above the noise of natural variability, especially in the summer at middle latitudes and year-round at low latitudes. Despite the small magnitude of warming relative to weather fluctuations, effects of the warming already have notable social and economic impacts. Global warming of 2 °C relative to preindustrial would shift the ‘bell curve’ defining temperature anomalies a factor of three larger than observed changes since the middle of the 20th century, with highly deleterious consequences. There is striking incongruity between the global distribution of nations principally responsible for fossil fuel CO2 emissions, known to be the main cause of climate change, and the regions suffering the greatest consequences from the warming, a fact with substantial implications for global energy and climate policies.

  17. Population variability complicates the accurate detection of climate change responses.

    Science.gov (United States)

    McCain, Christy; Szewczyk, Tim; Bracy Knight, Kevin

    2016-06-01

    The rush to assess species' responses to anthropogenic climate change (CC) has underestimated the importance of interannual population variability (PV). Researchers assume sampling rigor alone will lead to an accurate detection of response regardless of the underlying population fluctuations of the species under consideration. Using population simulations across a realistic, empirically based gradient in PV, we show that moderate to high PV can lead to opposite and biased conclusions about CC responses. Between pre- and post-CC sampling bouts of modeled populations as in resurvey studies, there is: (i) A 50% probability of erroneously detecting the opposite trend in population abundance change and nearly zero probability of detecting no change. (ii) Across multiple years of sampling, it is nearly impossible to accurately detect any directional shift in population sizes with even moderate PV. (iii) There is up to 50% probability of detecting a population extirpation when the species is present, but in very low natural abundances. (iv) Under scenarios of moderate to high PV across a species' range or at the range edges, there is a bias toward erroneous detection of range shifts or contractions. Essentially, the frequency and magnitude of population peaks and troughs greatly impact the accuracy of our CC response measurements. Species with moderate to high PV (many small vertebrates, invertebrates, and annual plants) may be inaccurate 'canaries in the coal mine' for CC without pertinent demographic analyses and additional repeat sampling. Variation in PV may explain some idiosyncrasies in CC responses detected so far and urgently needs more careful consideration in design and analysis of CC responses. PMID:26725404

  18. Ecological and methodological drivers of species’ distribution and phenology responses to climate change

    KAUST Repository

    Brown, Christopher J.

    2015-12-10

    Climate change is shifting species’ distribution and phenology. Ecological traits, such as mobility or reproductive mode, explain variation in observed rates of shift for some taxa. However, estimates of relationships between traits and climate responses could be influenced by how responses are measured. We compiled a global dataset of 651 published marine species’ responses to climate change, from 47 papers on distribution shifts and 32 papers on phenology change. We assessed the relative importance of two classes of predictors of the rate of change, ecological traits of the responding taxa and methodological approaches for quantifying biological responses. Methodological differences explained 22% of the variation in range shifts, more than the 7.8% of the variation explained by ecological traits. For phenology change, methodological approaches accounted for 4% of the variation in measurements, whereas 8% of the variation was explained by ecological traits. Our ability to predict responses from traits was hindered by poor representation of species from the tropics, where temperature isotherms are moving most rapidly. Thus, the mean rate of distribution change may be underestimated by this and other global syntheses. Our analyses indicate that methodological approaches should be explicitly considered when designing, analysing and comparing results among studies. To improve climate impact studies, we recommend that: (1) re-analyses of existing time-series state how the existing datasets may limit the inferences about possible climate responses; (2) qualitative comparisons of species’ responses across different studies be limited to studies with similar methodological approaches; (3) meta-analyses of climate responses include methodological attributes as covariates and; (4) that new time series be designed to include detection of early warnings of change or ecologically relevant change. Greater consideration of methodological attributes will improve the

  19. Novel competitors shape species' responses to climate change.

    Science.gov (United States)

    Alexander, Jake M; Diez, Jeffrey M; Levine, Jonathan M

    2015-09-24

    Understanding how species respond to climate change is critical for forecasting the future dynamics and distribution of pests, diseases and biological diversity. Although ecologists have long acknowledged species' direct physiological and demographic responses to climate, more recent work suggests that these direct responses can be overwhelmed by indirect effects mediated via other interacting community members. Theory suggests that some of the most dramatic impacts of community change will probably arise through the assembly of novel species combinations after asynchronous migrations with climate. Empirical tests of this prediction are rare, as existing work focuses on the effects of changing interactions between competitors that co-occur today. To explore how species' responses to climate warming depend on how their competitors migrate to track climate, we transplanted alpine plant species and intact plant communities along a climate gradient in the Swiss Alps. Here we show that when alpine plants were transplanted to warmer climates to simulate a migration failure, their performance was strongly reduced by novel competitors that could migrate upwards from lower elevation; these effects generally exceeded the impact of warming on competition with current competitors. In contrast, when we grew the focal plants under their current climate to simulate climate tracking, a shift in the competitive environment to novel high-elevation competitors had little to no effect. This asymmetry in the importance of changing competitor identity at the leading versus trailing range edges is best explained by the degree of functional similarity between current and novel competitors. We conclude that accounting for novel competitive interactions may be essential to predict species' responses to climate change accurately.

  20. Climate change and our responsibilities as chemists

    Directory of Open Access Journals (Sweden)

    Bassam Z. Shakhashiri

    2014-01-01

    Full Text Available For almost all of 4.5 billion years, natural forces have shaped Earth’s environment. But, during the past century, as a result of the Industrial Revolution, which has had enormous benefits for humans, the effects of human activities have become the main driver for climate change. The increase of atmospheric carbon dioxide caused by burning fossil fuels for energy to power the revolution causes an energy imbalance between incoming solar radiation and outgoing planetary emission. The imbalance is warming the planet and causing the atmosphere and oceans to warm, ice to melt, sea level to rise, and weather extremes to increase. In addition, dissolution of part of the carbon dioxide in the oceans is causing them to acidify, with possible negative effects on marine biota. As citizens of an interconnected global society and scientists who have the background to understand climate change, we have a responsibility first to understand the science. One resource that is available to help is the American Chemical Society Climate Science Toolkit, www.acs.org/climatescience. With this understanding our further responsibility as citizen scientists is to engage others in deliberative discussions on the science, to take actions ourselves to adapt to and mitigate human-caused climate change, and urge others to follow our example.

  1. Decoupling of soil C and N mineralization by labile C inputs explain high C sequestration rates in response to N fertilization

    Science.gov (United States)

    Bengtson, Per; Ehtesham, Emad

    2015-04-01

    During the last decade there have been an ongoing controversy regarding the extent to which N fertilization can increase C sequestration in forest ecosystems by stimulating primary production. There is also evidence that N fertilization commonly results in reduced soil respiration rates that cannot be fully explained by lower root respiration. Several hypotheses aimed at explaining the phenomenon have been proposed, but the mechanism remains elusive. The aim of this study was to examine if decreased decomposition and respiration of soil organic matter (SOM) in response to N fertilization can be explained by diminishing priming effects, and to determine to which extent priming of SOM decomposition is manifested as C or N mineralization under different loadings of labile C and N. We also aimed at determining if any changes that occur in response to N fertilization are long-term effects dependent on a shift in e.g. microbial community composition, or an immediate effect caused by increased N availability and decreased N mining. To achieve these aims we designed an experiment where the potential priming of microbial C and N mineralization was studied in a Norway spruce forest. SOM derived respiration, gross N mineralization and 13C-incorporation into microbial biomarker lipids (PLFA's) were measured 4 and 24 hours after addition of 13C-enriched glucose. Field treatments included control, N fertilization, and two levels of tree density. We also included a treatment where the control soil received inorganic N, at the same level as in the field N fertilization treatment, in addition to glucose. Glucose additions in most cases caused a significant reduction in microbial respiration of SOM, resulting in what is commonly referred to as "negative priming". In contrast, gross N mineralization rates generally increased in response to the glucose additions. Glucose additions, therefore, appeared to result in a decoupling of microbial respiration of SOM and gross N mineralization

  2. Resistance to change within heterogeneous response sequences.

    Science.gov (United States)

    Reid, Alliston K

    2009-07-01

    Three experiments investigated how instrumental and Pavlovian contingencies contribute to resistance to change (RTC) in different ordinal response positions within heterogeneous response sequences in pigeons. RTC in the initial and terminal response positions of a three-response sequence were compared in Experiment 1, which presented three colored key lights in succession in each trial; and in Experiment 2, which severely degraded Pavlovian contingencies by presenting the lights simultaneously at each ordinal position. Experiment 3 eliminated the instrumental contingency in a high-order sign-tracking procedure. When the instrumental contingency was in effect, RTC of the initial position was greater than the terminal position (Initial RTC > Terminal RTC) when the Pavlovian contingencies were strong and when they were degraded. When the instrumental contingency was eliminated, RTC patterns reversed, producing a graded pattern of RTC (Initial theory, conditioned reinforcement, and motivational control of instrumental conditioning) cannot account for these results. An alternative approach (a gradient model) shows that obtained measures of RTC in heterogeneous sequences may reflect a combination of three dissociable processes.

  3. Most stomatal closure in woody species under moderate drought can be explained by stomatal responses to leaf turgor.

    Science.gov (United States)

    Rodriguez-Dominguez, Celia M; Buckley, Thomas N; Egea, Gregorio; de Cires, Alfonso; Hernandez-Santana, Virginia; Martorell, Sebastia; Diaz-Espejo, Antonio

    2016-09-01

    Reduced stomatal conductance (gs ) during soil drought in angiosperms may result from effects of leaf turgor on stomata and/or factors that do not directly depend on leaf turgor, including root-derived abscisic acid (ABA) signals. To quantify the roles of leaf turgor-mediated and leaf turgor-independent mechanisms in gs decline during drought, we measured drought responses of gs and water relations in three woody species (almond, grapevine and olive) under a range of conditions designed to generate independent variation in leaf and root turgor, including diurnal variation in evaporative demand and changes in plant hydraulic conductance and leaf osmotic pressure. We then applied these data to a process-based gs model and used a novel method to partition observed declines in gs during drought into contributions from each parameter in the model. Soil drought reduced gs by 63-84% across species, and the model reproduced these changes well (r(2)  = 0.91, P drought. PMID:27255698

  4. Response of Sphagna to the changing environment

    Energy Technology Data Exchange (ETDEWEB)

    Vasander, H. [Helsinki Univ. (Finland). Dept. of Forest Ecology; Jauhiainen, J.; Silvola, J. [Joensuu Univ. (Finland). Dept. of Biology; Karsisto, M. [Finnish Forest Research Inst., Vantaa (Finland)

    1996-12-31

    During last decade, considerable interest has been focused to assess the influence of human activities on ecosystems. The increasing trend in the atmospheric concentration of CO{sub 2} has been predicted to continue till the next century and the amount of nitrogen deposition in the northern hemisphere has increased markedly. Substantial interest has been focused on predicting how these changes will affect on plants. Most boreal mire ecosystems are dominated by mosses of the genus Sphagnum, the litter of which constitutes the main component in the peat deposits and is an important CO{sub 2} sink via peat formation. Since virtually nothing was known about the growth response of peat mosses to elevated concentrations of CO{sub 2} and alerting changes in species composition were detected in the sensitive ombrotrophic mire vegetation under increased N deposition in central Europe, this study was established. Laboratory experiments focused on measurements of the patterns of growth, production and plant metabolism at increased CO{sub 2} and N deposition levels in peat moss species. Long term field experiments were established to study the growth response and spatial competition of two interacting Sphagnum species under the increased nitrogen deposition levels

  5. Macro-level drivers of multidimensional poverty in sub-Saharan Africa: Explaining change in the Human Poverty Index

    Directory of Open Access Journals (Sweden)

    Heath Prince

    2014-12-01

    Full Text Available Poverty is increasingly recognised as a multidimensional phenomenon in the development literature, encompassing not only income, but also a range of factors related to broadening an individual’s freedoms to live a life of their own choosing. Poverty so understood suggests that alternative approaches to poverty measurement reflecting this multidimensionality may point towards alternative policies for poverty alleviation. The imperative to reinforce pro-poor policy development in sub-Saharan Africa with evaluation findings that reflect improvements in well-being, rather than solely improvements in national economies, has become self-evident as, despite decades of market-led development policies, much of the subcontinent remains mired in deprivation. As recognised by the 2014 African Evaluation Association’s biannual conference, fresh thinking and new evaluation metrics are required in order to create policies that more effectively increase well-being. This article explores the factors that may account for changes in one metric of multidimensional poverty in developing countries, the United Nation Development Program’s Human Poverty Index (HPI, and will be primarily concerned with measuring the effects on the HPI of policies and activities that relate to, or are explicitly meant to encourage, economic growth, increased literacy and improved health. The study focuses on the outcomes of a panel data set, created for the purpose of this study, of HPI scores for a set of 47 sub-Saharan countries, between 1990 and 2010, and a range of indicators that the development literature and theory suggest should have an effect on income poverty, asking, what is the relationship between these indicators and multidimensional poverty? A parallel set of models has been developed to measure the response of household consumption expenditure to changes in economic growth and human capabilities indicators. All models are estimated using fixed effects estimators and

  6. Explaining global increases in water use efficiency: why have we overestimated responses to rising atmospheric CO(2 in natural forest ecosystems?

    Directory of Open Access Journals (Sweden)

    Lucas C R Silva

    Full Text Available BACKGROUND: The analysis of tree-ring carbon isotope composition (δ(13C has been widely used to estimate spatio-temporal variations in intrinsic water use efficiency (iWUE of tree species. Numerous studies have reported widespread increases in iWUE coinciding with rising atmospheric CO(2 over the past century. While this could represent a coherent global response, the fact that increases of similar magnitude were observed across biomes with no apparent effect on tree growth raises the question of whether iWUE calculations reflect actual physiological responses to elevated CO(2 levels. METHODOLOGY/RESULTS: Here we use Monte Carlo simulations to test if an artifact of calculation could explain observed increases in iWUE. We show that highly significant positive relationships between iWUE and CO(2 occur even when simulated data (randomized δ(13C values spanning the observed range are used in place of actual tree-ring δ(13C measurements. From simulated data sets we calculated non-physiological changes in iWUE from 1900 to present and across a 4000 m altitudinal range. This generated results strikingly similar to those reported in recent studies encompassing 22 species from tropical, subtropical, temperate, boreal and mediterranean ecosystems. Only 6 of 49 surveyed case studies showed increases in iWUE significantly higher than predicted from random values. CONCLUSIONS/SIGNIFICANCE: Our results reveal that increases in iWUE estimated from tree-ring δ(13C occur independently of changes in (13C discrimination that characterize physiological responses to elevated CO(2. Due to a correlation with CO(2 concentration, which is used as an independent factor in the iWUE calculation, any tree-ring δ(13C data set would inevitably generate increasing iWUE over time. Therefore, although consistent, previously reported trends in iWUE do not necessarily reflect a coherent global response to rising atmospheric CO(2. We discuss the significance of these findings

  7. Response diversity determines the resilience of ecosystems to environmental change.

    Science.gov (United States)

    Mori, Akira S; Furukawa, Takuya; Sasaki, Takehiro

    2013-05-01

    A growing body of evidence highlights the importance of biodiversity for ecosystem stability and the maintenance of optimal ecosystem functionality. Conservation measures are thus essential to safeguard the ecosystem services that biodiversity provides and human society needs. Current anthropogenic threats may lead to detrimental (and perhaps irreversible) ecosystem degradation, providing strong motivation to evaluate the response of ecological communities to various anthropogenic pressures. In particular, ecosystem functions that sustain key ecosystem services should be identified and prioritized for conservation action. Traditional diversity measures (e.g. 'species richness') may not adequately capture the aspects of biodiversity most relevant to ecosystem stability and functionality, but several new concepts may be more appropriate. These include 'response diversity', describing the variation of responses to environmental change among species of a particular community. Response diversity may also be a key determinant of ecosystem resilience in the face of anthropogenic pressures and environmental uncertainty. However, current understanding of response diversity is poor, and we see an urgent need to disentangle the conceptual strands that pervade studies of the relationship between biodiversity and ecosystem functioning. Our review clarifies the links between response diversity and the maintenance of ecosystem functionality by focusing on the insurance hypothesis of biodiversity and the concept of functional redundancy. We provide a conceptual model to describe how loss of response diversity may cause ecosystem degradation through decreased ecosystem resilience. We explicitly explain how response diversity contributes to functional compensation and to spatio-temporal complementarity among species, leading to long-term maintenance of ecosystem multifunctionality. Recent quantitative studies suggest that traditional diversity measures may often be uncoupled from

  8. Explaining Convergence

    DEFF Research Database (Denmark)

    Ooi, Can-Seng

    however overshadows another important complementary – but under-theorized and tacit – strategy: the accreditation approach. This paper gives attention to the accreditation strategy while presenting the branding of Singapore as a tourist destination. By looking at the Formula One car races in Singapore......It is widely assumed that the practice of city branding attempts to frame the place in a unique manner, so that it will stand out globally. The assertion of uniqueness has become an institutionalized global practice for celebrating city identity. The emphasis on uniqueness in the place brand...... as vibrant, glamorous and trendy. So, this paper shows why city branding authorities are learning from each other and pursuing similar ways in place branding. This partly explains why cities are becoming more alike, rather than different....

  9. Changes in spirituality partly explain health-related quality of life outcomes after Mindfulness-Based Stress Reduction

    OpenAIRE

    Greeson, Jeffrey M.; Webber, Daniel M.; Smoski, Moria J.; Brantley, Jeffrey G.; Ekblad, Andrew G.; Suarez, Edward C.; Wolever, Ruth Quillian

    2011-01-01

    Mindfulness-Based Stress Reduction is a secular behavioral medicine program that has roots in meditative spiritual practices. Thus, spirituality may partly explain Mindfulness-Based Stress Reduction outcomes. Participants (N = 279; M (SD) age = 45(12); 75% women) completed an online survey before and after an 8-week Mindfulness-Based Stress Reduction program. Structural equation modeling was used to test the hypothesis that, following Mindfulness-Based Stress Reduction, the relationship betwe...

  10. Adaptation responses of crops to climate change

    Energy Technology Data Exchange (ETDEWEB)

    Seino, Hiroshi [National Inst. of Agro-Environmental Sciences, Tsukuba, Ibaraki (Japan)

    1993-12-31

    Appreciable global climatic responses to increasing levels of atmospheric CO{sub 2} and other trace gases are expected to take place over the next 50 to 80 years. Increasing atmospheric concentrations of carbon dioxide and other greenhouse gases are producing or will produce changes in the climate of the Earth. In particular, numerous efforts of climate modeling project very substantial increase of surface air temperature. In addition to a general warming of the atmosphere, the possibility of increased summer dryness in the continental mid-latitudes has been suggested on the basis of both historical analogues and some General Circulation Model (GCM) studies. There are three types of effect of climatic change on agriculture: (1) the physiological (direct) effect of elevated levels of atmospheric CO{sub 2} on crop plants and weeds, (2) the effect of changes in parameters of climate (e.g., temperature, precipitation, and solar radiation) on plants and animals, and (3) the effects of climate-related rises in sea-level on land use. The direct effects of elevated CO{sub 2} are on photosynthesis and respiration and thereby on growth, and there are additional effects of increased CO{sub 2} on development, yield quality and stomatal aperture and water use. A doubling of CO{sub 2} increases the instantaneous photosynthetic rate by 30% to 100%, depending on the other environmental conditions, and reduce water requirements of plants by reducing transpiration (per unit leaf area) through reductions in stomatal aperture. A doubling of CO{sub 2} causes partial stomatal closure on both C{sub 3} and C{sub 4} plants (approximately a 40% decrease in aperture). In many experiments this results in reductions of transpiration of about 23% to 46%. However. there is considerable uncertainty over the magnitude of this in natural conditions.

  11. A change in vaccine efficacy and duration of protection explains recent rises in pertussis incidence in the United States.

    Directory of Open Access Journals (Sweden)

    Manoj Gambhir

    2015-04-01

    Full Text Available Over the past ten years the incidence of pertussis in the United States (U.S. has risen steadily, with 2012 seeing the highest case number since 1955. There has also been a shift over the same time period in the age group reporting the largest number of cases (aside from infants, from adolescents to 7-11 year olds. We use epidemiological modelling and a large case incidence dataset to explain the upsurge. We investigate several hypotheses for the upsurge in pertussis cases by fitting a suite of dynamic epidemiological models to incidence data from the National Notifiable Disease Surveillance System (NNDSS between 1990-2009, as well as incidence data from a variety of sources from 1950-1989. We find that: the best-fitting model is one in which vaccine efficacy and duration of protection of the acellular pertussis (aP vaccine is lower than that of the whole-cell (wP vaccine, (efficacy of the first three doses 80% [95% CI: 78%, 82%] versus 90% [95% CI: 87%, 94%], increasing the rate at which disease is reported to NNDSS is not sufficient to explain the upsurge and 3 2010-2012 disease incidence is predicted well. In this study, we use all available U.S. surveillance data to: 1 fit a set of mathematical models and determine which best explains these data and 2 determine the epidemiological and vaccine-related parameter values of this model. We find evidence of a difference in efficacy and duration of protection between the two vaccine types, wP and aP (aP efficacy and duration lower than wP. Future refinement of the model presented here will allow for an exploration of alternative vaccination strategies such as different age-spacings, further booster doses, and cocooning.

  12. To Fire or to Hoard? Explaining Japan’s Labor Market Response in the Great Recession

    OpenAIRE

    Chad Steinberg; Masato Nakane

    2011-01-01

    The Great Recession pushed Japan’s unemployment rate to historic highs, but the increase has been small by international standards and small relative to the large output shock. This paper explores Japan’s cyclical labor market response to the global financial crisis. Our findings suggest that: (i) employment responsiveness has been historically low but rising over time with the increasing importance of the non-regular workforce; (ii) the labor market response was consistent with historical pa...

  13. Explaining trends in alcohol-related harms in Scotland 1991–2011 (II): policy, social norms, the alcohol market, clinical changes and a synthesis

    OpenAIRE

    McCartney, G.; Bouttell, J.; Craig, N.; Craig, P.; Graham, L; Lakha, F.; Lewsey, J.; McAdams, R; MacPherson, M; Minton, J.; Parkinson, J.; Robinson, M; Shipton, D.; Taulbut, M.; D. Walsh

    2016-01-01

    Objective This paper tests the extent to which differing trends in income, demographic change and the consequences of an earlier period of social, economic and political change might explain differences in the magnitude and trends in alcohol-related mortality between 1991 and 2011 in Scotland compared to England & Wales (E&W). Study design Comparative time trend analyses and arithmetic modelling. Methods Three approaches were utilised to compare Scotland with E&W:...

  14. Neither DNA hypomethylation nor changes in the kinetics of erythroid differentiation explain 5-azacytidine's ability to induce human fetal hemoglobin

    OpenAIRE

    Mabaera, Rodwell; Greene, Michael R.; Richardson, Christine A.; Conine, Sarah J; Kozul, Courtney D.; Lowrey, Christopher H.

    2008-01-01

    5-azacytidine (5-Aza) is a potent inducer of fetal hemoglobin (HbF) in people with β-thalassemia and sickle cell disease. Two models have been proposed to explain this activity. The first is based on the drug's ability to inhibit global DNA methylation, including the fetal globin genes, resulting in their activation. The second is based on 5-Aza's cytotoxicity and observations that HbF production is enhanced during marrow recovery. We tested these models using human primary cells in an in vit...

  15. Cenozoic Mammals and Climate Change: The Contrast between Coarse-Scale versus High-Resolution Studies Explained by Species Sorting

    OpenAIRE

    Donald Prothero

    2012-01-01

    Many paleontologists have noticed the broadly similar patterns between the changes in Cenozoic mammalian diversity and taxonomic dominance and climate changes. Yet detailed studies of fossil population samples with fine-scale temporal resolution during episodes of climate change like the Eocene-Oligocene transition in the White River Group, and the late Pleistocene at Rancho La Brea tar pits, demonstrates that most fossil mammal species are static and show no significant microevolutionary res...

  16. A fractal climate response function can explain global temperature trends of the modern era and the past millennium

    CERN Document Server

    van Hateren, J H

    2013-01-01

    A climate response function is introduced that consists of six exponential (low-pass) filters with weights depending as a power law on their e-folding times. The response of this function to the combined forcings of solar irradiance, greenhouse gases, and SO2-related aerosols is fitted simultaneously to reconstructed temperatures of the past millennium, the response to solar cycles, the response to the 1991 Pinatubo volcanic eruption, and the modern 1850-2010 temperature trend. The quite adequate fit produces a climate response function with an equilibrium response to doubling of CO2 concentration of 2.0 \\pm 0.3 ^{\\circ}C (mean \\pm standard error), of which about 50% is realized with e-folding times of 0.5 and 2 years, about 30% with e-folding times of 8 and 32 years, and about 20% with e-folding times of 128 and 512 years. The transient climate response (response after 70 years of 1% yearly rise of CO2 concentration) is 1.5 \\pm 0.2 ^{\\circ}C. The temperature rise from 1820-1950 can be attributed for about 70...

  17. Can observed ecosystem responses to elevated CO2 and N fertilisation be explained by optimal plant C allocation?

    Science.gov (United States)

    Stocker, Benjamin; Prentice, I. Colin

    2016-04-01

    The degree to which nitrogen availability limits the terrestrial C sink under rising CO2 is a key uncertainty in carbon cycle and climate change projections. Results from ecosystem manipulation studies and meta-analyses suggest that plant C allocation to roots adjusts dynamically under varying degrees of nitrogen availability and other soil fertility parameters. In addition, the ratio of biomass production to GPP appears to decline under nutrient scarcity. This reflects increasing plant C export into the soil and to symbionts (Cex) with decreasing nutrient availability. Cex is consumed by an array of soil organisms and may imply an improvement of nutrient availability to the plant. These concepts are left unaccounted for in Earth system models. We present a model for the coupled cycles of C and N in grassland ecosystems to explore optimal plant C allocation under rising CO2 and its implications for the ecosystem C balance. The model follows a balanced growth approach, accounting for the trade-offs between leaf versus root growth and Cex in balancing C fixation and N uptake. We further model a plant-controlled rate of biological N fixation (BNF) by assuming that Cex is consumed by N2-fixing processes if the ratio of Nup:Cex falls below the inverse of the C cost of N2-fixation. The model is applied at two temperate grassland sites (SwissFACE and BioCON), subjected to factorial treatments of elevated CO2 (FACE) and N fertilization. Preliminary simulation results indicate initially increased N limitation, evident by increased relative allocation to roots and Cex. Depending on the initial state of N availability, this implies a varying degree of aboveground growth enhancement, generally consistent with observed responses. On a longer time scale, ecosystems are progressively released from N limitation due tighter N cycling. Allowing for plant-controlled BNF implies a quicker release from N limitation and an adjustment to more open N cycling. In both cases, optimal plant

  18. Do Changes in Job Mobility Explain the Growth of Wage Inequality among Men in the United States, 1977-2005?

    Science.gov (United States)

    Mouw, Ted; Kalleberg, Arne L.

    2010-01-01

    To what extent did the increase in wage inequality among men in the United States over the past three decades result from job loss and/or employment instability? We propose a simple method for decomposing the change in wage inequality into components due to upward and downward between-employer mobility and within-employer wage changes using data…

  19. An interdependent analytic approach to explaining the evolution of NGOs, social movements, and biased government response to AIDS and tuberculosis in Brazil.

    Science.gov (United States)

    Gómez, Eduardo J

    2013-02-01

    The politics of government response to health epidemics is a new area of scholarly research. Nevertheless, to date scholars have not considered how social science theory can be used and interdependently linked to provide a more thorough discussion of civil societal and national government response to different types of health epidemics. Introducing what I call an interdependent analytic framework of government response to epidemics, this article illustrates how social science theories can be interdependently linked and applied to help explain the evolutionary role of interest groups and social movements in response to AIDS and tuberculosis in Brazil, and when and why the government eventually responded more aggressively to AIDS but not tuberculosis. Evidence from Brazil suggests that the policy influence of interest groups and social movements evolves over time and is more influential after the national government implements new policies; moreover, this response is triggered by the rise of international pressures and government reputation building, not civil society. I highlight new areas of research that the framework provides and provide examples of how this approach can help explain civil societal and biased government responses to different types of epidemics in other nations.

  20. ‘Horrors of Holland’ : Explaining attitude change toward euthanasia and homosexuals in The Netherlands, 1971-1998

    NARCIS (Netherlands)

    Jaspers, Eva; Lubbers, Marcel; Graaf, Nan Dirk de

    2007-01-01

    In this article, we investigate changes in public opinion in the Netherlands toward two controversial issues: homosexuals and euthanasia. We find that a rapid decrease in opposition to both issues in the seventies and early eighties was followed by a period of a stable minority opposition. We identi

  1. Identification of farmer characteristics and farm strategies explaining changes in environmental management and environmental and economic performance of dairy farms

    NARCIS (Netherlands)

    Ondersteijn, C.J.M.; Giesen, G.W.J.; Huirne, R.B.M.

    2003-01-01

    In 1998, the Mineral Accounting System (MINAS) was introduced in The Netherlands. MINAS penalises farms with a levy if the farm nutrient surpluses exceed a certain threshold. The threshold is strict, meaning that most farmers need to change their environmental management and performance to avoid hig

  2. A Systems Perspective on Responses to Climate Change

    Science.gov (United States)

    The science of climate change integrates many scientific fields to explain and predict the complex effects of greenhouse gas concentrations on the planet’s energy balance, weather patterns, and ecosystems as well as economic and social systems. A changing climate requires respons...

  3. Antarctic terrestrial ecosystems: responses to environmental change

    OpenAIRE

    Convey, Peter

    2006-01-01

    The consequences of climate change are exciting considerable concern worldwide. Parts of Antarctica are facing the most rapid rates of anthropogenic climate change currently seen on the planet. This paper sets out to introduce contemporary ecosystems of the Antarctic, and the factors that have influenced them and their biodiversity over evolutionary timescales. Contemporary climate change processes significant to terrestrial biota, and the biological consequences of these changes seen t...

  4. The Diffusion of Global Models of Appropriate Leadership Behavior: Explaining Changing Leadership Priorities of High Ranking Public Managers

    DEFF Research Database (Denmark)

    Hansen, Morten Balle

    , which emphasizes the importance of diffusion and translation of global models of legitimate behavior. The hypothesis is that certain globally legitimated notions of good leadership gradually became more widespread among municipal senior managers from the start of the 1990s to the end of the 2000s......The question posed is whether and how public senior managers’ perceptions of what is important in performing their roles have changed from the beginning of the 1990s to the end of the 2000s. The theoretical approach to the analysis is based on a macro-phenomenological institutional perspective....... The empirical analyses are based on multivariate regression analyses of survey data generated among Danish municipal senior managers in 1992, 2006 and 2008. The study clearly indicates that a change has taken place in leadership orientation among Danish municipal senior managers towards globally legitimated...

  5. Intimacy as a Concept: Explaining Social Change in the Context of Globalisation or Another Form of Ethnocentricism?

    OpenAIRE

    Lynn Jamieson

    2011-01-01

    This article focuses on intimacy in terms of its analytical potential for understanding social change without the one-nation blinkers sometimes referred to as 'methodological nationalism' and without Euro-North-American ethnocentrism. Extending from the concept of family practices, practices of intimacy are sketched and examples considered across cultures. The cultural celebration and use of the term 'intimacy' is not universal, but practices of intimacy are present in all cultures. The relat...

  6. Exploring models for the roles of health systems’ responsiveness and social determinants in explaining universal health coverage and health outcomes

    OpenAIRE

    Valentine, Nicole Britt; Bonsel, Gouke J.

    2016-01-01

    Background: Intersectoral perspectives of health are present in the rhetoric of the sustainable development goals. Yet its descriptions of systematic approaches for an intersectoral monitoring vision, joining determinants of health, and barriers or facilitators to accessing healthcare services are lacking.Objective: To explore models of associations between health outcomes and health service coverage, and health determinants and health systems responsiveness, and thereby to contribute to moni...

  7. A dampened land use change climate response towards the tropics

    NARCIS (Netherlands)

    Molen, van der M.K.; Hurk, van den B.J.J.M.; Hazeleger, W.

    2011-01-01

    In climate simulations we find a pronounced meridional (equator to pole) gradient of climate response to land cover change. Climate response approaches zero in the tropics, and increases towards the poles. The meridional gradient in climate response to land cover change results from damping feedback

  8. A response to Mimics of child abuse: Can choking explain abusive head trauma? [35 (2015) 33-37].

    Science.gov (United States)

    Galaznik, John G

    2016-04-01

    In the recently published article in this journal, "Mimics of Child Abuse: Can Choking Explain Abusive Head Trauma?",(1) the author chose to revisit a discussion prompted by a case report from 5 years ago which was inappropriate in his opinion. He went further to suggest that bringing an unvalidated mechanism of injury into the legal setting "obstructs justice", is a "further victimization of the child", and is a "travesty of justice".(1) Given the "Shaken Baby Syndrome: Rotational Cranial Injuries" has always been only an unvalidated hypothesis lacking experimental confirmation, the exploring of alternative injury mechanisms should be entirely appropriate. In 2010, the post publication discussion ended with a challenge to the American Academy of Pediatrics Committee on Child Abuse and Neglect (AAP COCAN) to either support the pure shaking mechanism with quality EBMS or eliminate any positive support for it from any official policy statement until the exact nature of each injury that pure abusive shaking has the potential to cause is clearly defined and supported with quality experimental research.(4) Since this is an area of acknowledged controversy by the AAP, it is appropriate to examine the evidence based experimental literature that has emerged over the last five years that is relevant to the abusive shaking hypothesis and the hypothesis of any primary brain-lethal hypoxic event leading to the findings of retinal hemorrhages, extra-axial bleeding, and brain injury when an infant presents to medical attention after an Acute/Apparent Life Threatening Event. In that light, this review was undertaken. PMID:26828828

  9. Why the 18.6 year tide cannot explain the change of sign observed in j2

    Directory of Open Access Journals (Sweden)

    F. Deleflie

    2003-01-01

    Full Text Available Recent studies show a change, starting in 1998, in the behavior of the variation of the dynamical flattening of the Earth (J2, supposed to be constant (secular, and mainly due to the post glacial rebound effect. In this paper, we study to what extent this behavior can be correlated or not with the 18.6 year tide: with more than twenty years of tracking data on LAGEOS-1, that is to say more than a period of 18.6 years, this effect can now be separated from the secular variation. We use our theory of mean orbital motion, dedicated to studies of the long period effects on the orbital motion. We build one single arc of LAGEOS-1 from 1980 to 2002, which provides a continuous description of the orbital parameters. This is the great originality of our approach. We focus our attention on the ascending node of LAGEOS-1, and we show that the change observed in j2 cannot be attributed to a statistical error due to a correlation, in short arcs results, between the secular variation of J2 and the 18.6 year tide. The proof is based on the adjustment of amplitudes and phases of the long period tides, and on the shape of the residuals.Key words. secular variation of J2, 18.6 year tide, mean orbital motione

  10. Changing CS Features Alters Evaluative Responses in Evaluative Conditioning

    Science.gov (United States)

    Unkelbach, Christian; Stahl, Christoph; Forderer, Sabine

    2012-01-01

    Evaluative conditioning (EC) refers to changes in people's evaluative responses toward initially neutral stimuli (CSs) by mere spatial and temporal contiguity with other positive or negative stimuli (USs). We investigate whether changing CS features from conditioning to evaluation also changes people's evaluative response toward these CSs. We used…

  11. Soil bacterial community responses to global changes

    DEFF Research Database (Denmark)

    Bergmark, Lasse

    the bacterial soil population. The thesis addresses the effects of different global change manipulations on the soil microbial community composition (climate change in Manuscript 1-4 and unconventional urban fertilizers in Manuscript 5-6). A special emphasis was put on combining molecular techniques like 454......’ of climate change manipulations on soil microorganisms and nutrient availability in a Danish heathland, where the samples were taken shortly after a prolonged pre-summer drought. The major findings in the study are that warming increased measures of fungi and bacteria and drought might shift/change...... overall importance for ecosystem function in soil is poorly understood. Global change factors may affect the diversity and functioning of soil prokaryotes and thereby ecosystem functioning. To gain a better understanding of the effects of global changes it is of fundamental importance to classify...

  12. Comment 5 - agricultural response to climate change

    International Nuclear Information System (INIS)

    The complex interrelationship between global climate change and agricultural production will become one of the most significant policy issues, in both developed and developing countries, in the first decades of the 21st century. Global and regional climate change will modify both agricultural production capacity and its location. And the intensity of agricultural production will contribute to environmental change at both the regional and global levels

  13. Vascular Steal Explains Early Paradoxical Blood Oxygen Level-Dependent Cerebrovascular Response in Brain Regions with Delayed Arterial Transit Times

    Directory of Open Access Journals (Sweden)

    Julien Poublanc

    2013-04-01

    Full Text Available Introduction: Blood oxygen level-dependent (BOLD magnetic resonance imaging (MRI during manipulation of inhaled carbon dioxide (CO2 can be used to measure cerebrovascular reactivity (CVR and map regions of exhausted cerebrovascular reserve. These regions exhibit a reduced or negative BOLD response to inhaled CO2. In this study, we sought to clarify the mechanism behind the negative BOLD response by investigating its time delay (TD. Dynamic susceptibility contrast (DSC MRI with the injection of a contrast agent was used as the gold standard in order to provide measurement of the blood arrival time to which CVR TD could be compared. We hypothesize that if negative BOLD responses are the result of a steal phenomenon, they should be synchronized with positive BOLD responses from healthy brain tissue, even though the blood arrival time would be delayed. Methods: On a 3-tesla MRI system, BOLD CVR and DSC images were collected in a group of 19 patients with steno-occlusive cerebrovascular disease. For each patient, we generated a CVR magnitude map by regressing the BOLD signal with the end-tidal partial pressure of CO2 (PETCO2, and a CVR TD map by extracting the time of maximum cross-correlation between the BOLD signal and PETCO2. In addition, a blood arrival time map was generated by fitting the DSC signal with a gamma variate function. ROI masks corresponding to varying degrees of reactivity were constructed. Within these masks, the mean CVR magnitude, CVR TD and DSC blood arrival time were extracted and averaged over the 19 patients. CVR magnitude and CVR TD were then plotted against DSC blood arrival time. Results: The results show that CVR magnitude is highly correlated to DSC blood arrival time. As expected, the most compromised tissues with the longest blood arrival time have the lowest (most negative CVR magnitude. However, CVR TD shows a noncontinuous relationship with DSC blood arrival time. CVR TD is well correlated to DSC blood arrival time

  14. Explaining Varying Asian Responses to China: Strategic Evolution in the Cases of Japan, Korea, and Thailand

    OpenAIRE

    FEI, John

    2012-01-01

    Domestic strategic preferences among state elites to prioritize economic and technological facets of national security have played a significant role in shaping the foreign policies of many Asian nations. This paper considers the role that elite preferences for economic and technological strength—preferences which are embedded and institutionalized in domestic political structures—played in shaping the security and economic policy responses of Japan, Korea, and Thailand towards China between ...

  15. Explaining Varying Asian Responses to China: Strategic Evolution in the Cases of Japan, Korea, and Thailand

    OpenAIRE

    FEI, John

    2012-01-01

    Domestic strategic preferences among state elites to prioritize economic and technological facets of national security have played a significant role in shaping the foreign policies of many Asian nations. This paper considers the role that elite preferences for economic and technological strength—preferences which are embedded and institutionalized in domestic political structures—played in shaping the security and economic policy responses of Japan, Korea, and Thailand towards Chi...

  16. Responsibility of Educational Institutions for Strategic Change

    Science.gov (United States)

    Rebolloso, Enrique; Fernandez-Ramirez, Baltasar; Canton, Pilar:

    2008-01-01

    The Spanish university is well into its nth reform process, this time for the purpose of improving its legibility for members of the European Union under the extended Bologna Process. The reform involves a structural change in plans of study, as well as a cultural change to the Europeanist discourse, which mixes mercantilist values and defence of…

  17. Successional change in phosphorus stoichiometry explains the inverse relationship between herbivory and lupin density on Mount St. Helens.

    Directory of Open Access Journals (Sweden)

    Jennifer L Apple

    Full Text Available BACKGROUND: The average nitrogen-to-phosphorus ratio (NratioP of insect herbivores is less than that of leaves, suggesting that P may mediate plant-insect interactions more often than appreciated. We investigated whether succession-related heterogeneity in N and P stoichiometry influences herbivore performance on N-fixing lupin (Lupinus lepidus colonizing primary successional volcanic surfaces, where the abundances of several specialist lepidopteran herbivores are inversely related to lupin density and are known to alter lupin colonization dynamics. We examined larval performance in response to leaf nutritional characteristics using gelechiid and pyralid leaf-tiers, and a noctuid leaf-cutter. METHODOLOGY/PRINCIPAL FINDINGS: We conducted four studies. First, growth of larvae raised on wild-collected leaves responded positively to leaf %P and negatively to leaf carbon (%C, but there was no effect of %N or quinolizidine alkaloids (QAs. Noctuid survival was also positively related to %P. Second, we raised gelechiid larvae on greenhouse-grown lupins with factorial manipulation of competitors and soil N and P. In the presence of competition, larval mass was highest at intermediate leaf NratioP and high %P. Third, survival of gelechiid larvae placed on lupins in high-density patches was greater when plant competitors were removed than on controls. Fourth, surveys of field-collected leaves in 2000, 2002, and 2003 indicated that both %P and %N were generally greater in plants from low-density areas. QAs in plants from low-density areas were equal to or higher than QAs in high-density areas. CONCLUSIONS/SIGNIFICANCE: Our results demonstrate that declines in lupin P content under competitive conditions are associated with decreased larval growth and survival sufficient to cause the observed negative relationship between herbivore abundance and host density. The results support the theoretical finding that declines in stoichiometric resource quality (caused

  18. Responses of large mammals to climate change.

    Science.gov (United States)

    Hetem, Robyn S; Fuller, Andrea; Maloney, Shane K; Mitchell, Duncan

    2014-01-01

    Most large terrestrial mammals, including the charismatic species so important for ecotourism, do not have the luxury of rapid micro-evolution or sufficient range shifts as strategies for adjusting to climate change. The rate of climate change is too fast for genetic adaptation to occur in mammals with longevities of decades, typical of large mammals, and landscape fragmentation and population by humans too widespread to allow spontaneous range shifts of large mammals, leaving only the expression of latent phenotypic plasticity to counter effects of climate change. The expression of phenotypic plasticity includes anatomical variation within the same species, changes in phenology, and employment of intrinsic physiological and behavioral capacity that can buffer an animal against the effects of climate change. Whether that buffer will be realized is unknown, because little is known about the efficacy of the expression of plasticity, particularly for large mammals. Future research in climate change biology requires measurement of physiological characteristics of many identified free-living individual animals for long periods, probably decades, to allow us to detect whether expression of phenotypic plasticity will be sufficient to cope with climate change. PMID:27583293

  19. Responses of large mammals to climate change.

    Science.gov (United States)

    Hetem, Robyn S; Fuller, Andrea; Maloney, Shane K; Mitchell, Duncan

    2014-01-01

    Most large terrestrial mammals, including the charismatic species so important for ecotourism, do not have the luxury of rapid micro-evolution or sufficient range shifts as strategies for adjusting to climate change. The rate of climate change is too fast for genetic adaptation to occur in mammals with longevities of decades, typical of large mammals, and landscape fragmentation and population by humans too widespread to allow spontaneous range shifts of large mammals, leaving only the expression of latent phenotypic plasticity to counter effects of climate change. The expression of phenotypic plasticity includes anatomical variation within the same species, changes in phenology, and employment of intrinsic physiological and behavioral capacity that can buffer an animal against the effects of climate change. Whether that buffer will be realized is unknown, because little is known about the efficacy of the expression of plasticity, particularly for large mammals. Future research in climate change biology requires measurement of physiological characteristics of many identified free-living individual animals for long periods, probably decades, to allow us to detect whether expression of phenotypic plasticity will be sufficient to cope with climate change.

  20. Postglacial climate changes and vegetation responses in northern Europe

    Energy Technology Data Exchange (ETDEWEB)

    Heikkilae, M.

    2010-07-01

    Postglacial climate changes and vegetation responses were studied using a combination of biological and physical indicators preserved in lake sediments. Low-frequency trends, high-frequency events and rapid shifts in temperature and moisture balance were probed using pollenbased quantitative temperature reconstructions and oxygen-isotopes from authigenic carbonate and aquatic cellulose, respectively. Pollen and plant macrofossils were employed to shed light on the presence and response rates of plant populations in response to climate changes, particularly focusing on common boreal and temperate tree species. Additional geochemical and isotopic tracers facilitated the interpretation of pollen- and oxygen-isotope data. The results show that the common boreal trees (Betula sp., Pinus sylvestris, Picea abies) were present in the Baltic region (approx55 deg N) during the Lateglacial, which contrasts with the traditional view of species refuge locations in the south-European peninsulas during the glacial/ interglacial cycles. The findings of this work are in agreement with recent paleoecological and genetic evidence suggesting that scattered populations of tree species persisted at higher latitudes, and that these taxa were likely limited to boreal trees. Moreover, the results demonstrate that stepwise changes in plant communities took place in concert with major climate fluctuations of the glacial/interglacial transition. Postglacial climate trends in northern Europe were characterized by rise, maxima and fall in temperatures and related changes in moisture balance. Following the deglaciation of the Northern Hemisphere and the early Holocene reorganization of the ice-ocean-atmosphere system, the long-term temperature trends followed gradually decreasing summer insolation. The early Holocene (approx11,700-8000 cal yr BP) was overall cool, moist and oceanic, although the earliest Holocene effective humidity may have been low particularly in the eastern part of northern

  1. Numerical experiments to explain multiscale hydrological responses to mountain pine beetle tree mortality in a headwater watershed

    Science.gov (United States)

    Penn, Colin A.; Bearup, Lindsay A.; Maxwell, Reed M.; Clow, David W.

    2016-04-01

    The effects of mountain pine beetle (MPB)-induced tree mortality on a headwater hydrologic system were investigated using an integrated physical modeling framework with a high-resolution computational grid. Simulations of MPB-affected and unaffected conditions, each with identical atmospheric forcing for a normal water year, were compared at multiple scales to evaluate the effects of scale on MPB-affected hydrologic systems. Individual locations within the larger model were shown to maintain hillslope-scale processes affecting snowpack dynamics, total evapotranspiration, and soil moisture that are comparable to several field-based studies and previous modeling work. Hillslope-scale analyses also highlight the influence of compensating changes in evapotranspiration and snow processes. Reduced transpiration in the Grey Phase of MPB-induced tree mortality was offset by increased late-summer evaporation, while overall snowpack dynamics were more dependent on elevation effects than MPB-induced tree mortality. At the watershed scale, unaffected areas obscured the magnitude of MPB effects. Annual water yield from the watershed increased during Grey Phase simulations by 11 percent; a difference that would be difficult to diagnose with long-term gage observations that are complicated by inter-annual climate variability. The effects on hydrology observed and simulated at the hillslope scale can be further damped at the watershed scale, which spans more life zones and a broader range of landscape properties. These scaling effects may change under extreme conditions, e.g., increased total MPB-affected area or a water year with above average snowpack.

  2. Numerical experiments to explain multiscale hydrological responses to mountain pine beetle tree mortality in a headwater watershed

    Science.gov (United States)

    Penn, Colin A.; Bearup, Lindsay A.; Maxwell, Reed M.; Clow, David W.

    2016-01-01

    The effects of mountain pine beetle (MPB)-induced tree mortality on a headwater hydrologic system were investigated using an integrated physical modeling framework with a high-resolution computational grid. Simulations of MPB-affected and unaffected conditions, each with identical atmospheric forcing for a normal water year, were compared at multiple scales to evaluate the effects of scale on MPB-affected hydrologic systems. Individual locations within the larger model were shown to maintain hillslope-scale processes affecting snowpack dynamics, total evapotranspiration, and soil moisture that are comparable to several field-based studies and previous modeling work. Hillslope-scale analyses also highlight the influence of compensating changes in evapotranspiration and snow processes. Reduced transpiration in the Grey Phase of MPB-induced tree mortality was offset by increased late-summer evaporation, while overall snowpack dynamics were more dependent on elevation effects than MPB-induced tree mortality. At the watershed scale, unaffected areas obscured the magnitude of MPB effects. Annual water yield from the watershed increased during Grey Phase simulations by 11 percent; a difference that would be difficult to diagnose with long-term gage observations that are complicated by inter-annual climate variability. The effects on hydrology observed and simulated at the hillslope scale can be further damped at the watershed scale, which spans more life zones and a broader range of landscape properties. These scaling effects may change under extreme conditions, e.g., increased total MPB-affected area or a water year with above average snowpack.

  3. Undocumented migration in response to climate change

    Science.gov (United States)

    Riosmena, Fernando; Hunter, Lori M.; Runfola, Daniel M.

    2016-01-01

    In the face of climate change induced economic uncertainty, households may employ migration as an adaptation strategy to diversify their livelihood portfolio through remittances. However, it is unclear whether such climate migration will be documented or undocumented. In this study we combine detailed migration histories with daily temperature and precipitation information for 214 weather stations to investigate whether climate change more strongly impacts undocumented or documented migration from 68 rural Mexican municipalities to the U.S. during the years 1986–1999. We employ two measures of climate change, the warm spell duration index (WSDI) and the precipitation during extremely wet days (R99PTOT). Results from multi-level event-history models demonstrate that climate-related international migration from rural Mexico was predominantly undocumented. We conclude that programs to facilitate climate change adaptation in rural Mexico may be more effective in reducing undocumented border crossings than increased border fortification.

  4. Multi-epitope Models Explain How Pre-existing Antibodies Affect the Generation of Broadly Protective Responses to Influenza

    Science.gov (United States)

    Zarnitsyna, Veronika I.; Lavine, Jennie; Ellebedy, Ali; Ahmed, Rafi; Antia, Rustom

    2016-01-01

    The development of next-generation influenza vaccines that elicit strain-transcendent immunity against both seasonal and pandemic viruses is a key public health goal. Targeting the evolutionarily conserved epitopes on the stem of influenza’s major surface molecule, hemagglutinin, is an appealing prospect, and novel vaccine formulations show promising results in animal model systems. However, studies in humans indicate that natural infection and vaccination result in limited boosting of antibodies to the stem of HA, and the level of stem-specific antibody elicited is insufficient to provide broad strain-transcendent immunity. Here, we use mathematical models of the humoral immune response to explore how pre-existing immunity affects the ability of vaccines to boost antibodies to the head and stem of HA in humans, and, in particular, how it leads to the apparent lack of boosting of broadly cross-reactive antibodies to the stem epitopes. We consider hypotheses where binding of antibody to an epitope: (i) results in more rapid clearance of the antigen; (ii) leads to the formation of antigen-antibody complexes which inhibit B cell activation through Fcγ receptor-mediated mechanism; and (iii) masks the epitope and prevents the stimulation and proliferation of specific B cells. We find that only epitope masking but not the former two mechanisms to be key in recapitulating patterns in data. We discuss the ramifications of our findings for the development of vaccines against both seasonal and pandemic influenza. PMID:27336297

  5. What Can Plasticity Contribute to Insect Responses to Climate Change?

    Science.gov (United States)

    Sgrò, Carla M; Terblanche, John S; Hoffmann, Ary A

    2016-01-01

    Plastic responses figure prominently in discussions on insect adaptation to climate change. Here we review the different types of plastic responses and whether they contribute much to adaptation. Under climate change, plastic responses involving diapause are often critical for population persistence, but key diapause responses under dry and hot conditions remain poorly understood. Climate variability can impose large fitness costs on insects showing diapause and other life cycle responses, threatening population persistence. In response to stressful climatic conditions, insects also undergo ontogenetic changes including hardening and acclimation. Environmental conditions experienced across developmental stages or by prior generations can influence hardening and acclimation, although evidence for the latter remains weak. Costs and constraints influence patterns of plasticity across insect clades, but they are poorly understood within field contexts. Plastic responses and their evolution should be considered when predicting vulnerability to climate change-but meaningful empirical data lag behind theory. PMID:26667379

  6. Population dynamical responses to climate change

    DEFF Research Database (Denmark)

    Forchhammer, Mads; Schmidt, Niels Martin; Høye, Toke Thomas;

    2008-01-01

    , the effects of climate change may potentially extend through any of these interactions. In this chapter, we focus on the extent to which evolutionarily distinct species at different trophic levels respond to similar changes in climate. By using a broad spectrum of statistically and ecologically founded...... and three out of five wader species, displayed significant direct density dependence. Only two species (sanderling and long-tailed skua) displayed dynamics characterised by delayed density dependence. The direct effects of previous winter's snow were related to over-wintering strategies of resident...... of arctic fox were not significantly related to changes in lemming abundance, both the stoat and the breeding of long-tailed skua were mainly related to lemming dynamics. The predator-prey system at Zackenberg differentiates from previously described systems in high-arctic Greenland, which, we suggest...

  7. Response Strategies for Curriculum Change in Engineering

    Science.gov (United States)

    Kolmos, Anette; Hadgraft, Roger G.; Holgaard, Jette Egelund

    2016-01-01

    During the last 25 years, there have been many calls for new engineering competencies and a corresponding gradual change in both curriculum and pedagogy in engineering education. This has been a global trend, in the US, Europe, Australia and now emerging in the rest of the world. Basically, there have been two main types of societal challenges…

  8. Soil fungal community responses to global changes

    DEFF Research Database (Denmark)

    Haugwitz, Merian Skouw

    composition of fungi, but the effects were generally limited to the litter layer and the uppermost humus layer (0-5 cm), which was unexpected considering the ecosystem had been manipulated for 18 years. Taken together the global change experiments altered the soil fungal communities and thereby highlight...

  9. Developmental Change in Social Responsibility during Adolescence: An Ecological Perspective

    Science.gov (United States)

    Wray-Lake, Laura; Syvertsen, Amy K.; Flanagan, Constance A.

    2016-01-01

    Social responsibility can be defined as a set of prosocial values representing personal commitments to contribute to community and society. Little is known about developmental change--and predictors of that change--in social responsibility during adolescence. The present study used an accelerated longitudinal research design to investigate the…

  10. Climate change and our responsibilities as chemists

    OpenAIRE

    Bassam Z. Shakhashiri; Jerry A. Bell

    2014-01-01

    For almost all of 4.5 billion years, natural forces have shaped Earth’s environment. But, during the past century, as a result of the Industrial Revolution, which has had enormous benefits for humans, the effects of human activities have become the main driver for climate change. The increase of atmospheric carbon dioxide caused by burning fossil fuels for energy to power the revolution causes an energy imbalance between incoming solar radiation and outgoing planetary emission. The imbalance ...

  11. Computer jargon explained

    CERN Document Server

    Enticknap, Nicholas

    2014-01-01

    Computer Jargon Explained is a feature in Computer Weekly publications that discusses 68 of the most commonly used technical computing terms. The book explains what the terms mean and why the terms are important to computer professionals. The text also discusses how the terms relate to the trends and developments that are driving the information technology industry. Computer jargon irritates non-computer people and in turn causes problems for computer people. The technology and the industry are changing so rapidly; it is very hard even for professionals to keep updated. Computer people do not

  12. Retirement responses to social security changes.

    Science.gov (United States)

    Gohmann, S F; Clark, R L

    1989-11-01

    Workers often retire at an age later than the age at which they accept Social Security benefits. This study employed a life-cycle model of individual utility to examine the effects of Social Security provisions on the timing of benefit acceptance and retirement. The behavioral responses of older workers are estimated with a two-equation logit model using data from the Retirement History Study. The results indicate that the legislated increase in the age of eligibility for full Social Security benefits beginning in the 21st century will have relatively small effects on the ages of retirement and benefit acceptance. The mandated decrease in the earnings test tax also is predicted to have only a small effect on the behavior of older persons.

  13. Can life history trade-offs explain the evolution of short stature in human pygmies? A response to Migliano et al. (2007).

    Science.gov (United States)

    Becker, Noémie S A; Verdu, Paul; Hewlett, Barry; Pavard, Samuel

    2010-02-01

    Walker et al. ["Growth rates and life histories in twenty-two small-scale societies," Am. J. Hum. Biol. 18:295-311 (2006)] used life history theory to develop an innovative explanation for human diversity in stature. Short stature could have been selected for in some human populations as a result of the advantage of an earlier growth cessation and earlier reproduction in a context of high mortality. Migliano et al. ["Life history trade-offs explain the evolution of human pygmies," Proc. Natl. Acad. Sci. USA 104:20,216-20,219 (2007)] recently published an important article that tested this hypothesis to explain short stature in human pygmy populations. However innovative this work may be, we believe that some of the data and results presented are controversial if not questionable. As problematic points we note (1) the use of an arbitrary threshold of height (155 cm) to categorize populations into pygmies and nonpygmies; (2) the use of demographic data from Philippine pygmy groups that have experienced dramatic cultural and environmental changes in the last 20 years, and (3) the use of demographic data concerning African pygmy groups because good systematic data on these groups are not available. Finally, we report here mathematical errors and loopholes in the optimization model developed by Migliano and colleagues. In this paper we suggest alternative trade-offs that can be used to explain Migliano's results on more reliable bases.

  14. The physician's response to climate change.

    Science.gov (United States)

    Sarfaty, Mona; Abouzaid, Safiya

    2009-05-01

    Climate change will have an effect on the health and well-being of the populations cared for by practicing physicians. The anticipated medical effects include heat- and cold-related deaths, cardiovascular illnesses, injuries and mental harms from extreme weather events, respiratory illnesses caused by poor air quality, infectious diseases that emanate from contaminated food, water, or spread of disease vectors, the injuries caused by natural disasters, and the mental harm associated with social disruption. Within several years, such medical problems are likely to reach the doorsteps of many physicians. In the face of this reality, physicians should assume their traditional roles as medical professionals, health educators, and community leaders. Clinicians provide individual health services to patients, some of whom will be especially vulnerable to the emerging health consequences of global warming. Physicians also work in academic medical institutions and hospitals that educate and provide continuing medical education to students, residents, and practitioners. The institutions also produce a measurable carbon footprint. Societies of physicians at national, state, and local levels can choose to use their well-developed avenues of communication to raise awareness of the key issues that are raised by climate change as well as other environmental concerns that have profound implications for human health and well-being. PMID:19418286

  15. The physician's response to climate change.

    Science.gov (United States)

    Sarfaty, Mona; Abouzaid, Safiya

    2009-05-01

    Climate change will have an effect on the health and well-being of the populations cared for by practicing physicians. The anticipated medical effects include heat- and cold-related deaths, cardiovascular illnesses, injuries and mental harms from extreme weather events, respiratory illnesses caused by poor air quality, infectious diseases that emanate from contaminated food, water, or spread of disease vectors, the injuries caused by natural disasters, and the mental harm associated with social disruption. Within several years, such medical problems are likely to reach the doorsteps of many physicians. In the face of this reality, physicians should assume their traditional roles as medical professionals, health educators, and community leaders. Clinicians provide individual health services to patients, some of whom will be especially vulnerable to the emerging health consequences of global warming. Physicians also work in academic medical institutions and hospitals that educate and provide continuing medical education to students, residents, and practitioners. The institutions also produce a measurable carbon footprint. Societies of physicians at national, state, and local levels can choose to use their well-developed avenues of communication to raise awareness of the key issues that are raised by climate change as well as other environmental concerns that have profound implications for human health and well-being.

  16. Exporter Price Response to Exchange Rate Changes

    DEFF Research Database (Denmark)

    Fosse, Henrik Barslund

    Firms exporting to foreign markets face a particular challenge: to price their exports in a foreign market when the exchange rate changes. This paper takes on pricing- to-market using a unique data set that covers rm level monthly trade at great detail. As opposed to annual trade ows, monthly trade...... ows bring us closer to the transaction level where rm decisions are actually made. I nd that the utilization of monthly data does add new information about the average level of pricing-to-market, and the di¤erences between long-run pricing-to-market and short-run pricing-to-market. Furthermore, I nd...... industry di¤erences in pricing-to-market in terms of the magnitude (zero to complete pricing-to-market) and the timing (when do rms changes prices), and that pricing-to-market is stronger on high-income markets. As discussed in detail in the paper, all results are in-line with predictions of several...

  17. Temperature extremes in Europe: mechanisms and responses to climatic change

    International Nuclear Information System (INIS)

    Europe witnessed a spate of record-breaking warm seasons during the 2000's. As illustrated by the devastating heat-wave of the summer 2003, these episodes induced strong societal and environmental impacts. Such occurrence of exceptional events over a relatively short time period raised up many questionings in the present context of climate change. In particular, can recent temperature extremes be considered as 'previews' of future climate conditions? Do they result from an increasing temperature variability? These questions constitute the main motivations of this thesis. Thus, our work aims to contribute to the understanding of physical mechanisms responsible for seasonal temperature extremes in Europe, in order to anticipate their future statistical characteristics. Involved processes are assessed by both statistical data-analysis of observations and climate projections and regional modeling experiments. First we show that while the inter-annual European temperature variability appears driven by disturbances in the North-Atlantic dynamics, the recent warming is likely to be dissociated with potential circulation changes. This inconsistency climaxes during the exceptionally mild autumn of 2006, whose temperature anomaly is only half explained by the atmospheric flow. Recent warm surface conditions in the North-Atlantic ocean seem to substantially contribute to the European warming in autumn-winter, through the establishment of advective and radiative processes. In spring-summer, since both advection by the westerlies and Atlantic warming are reduced, more local processes appear predominant (e.g. soil moisture, clouds, aerosols). Then the issue of future evolution of the relationship between North-Atlantic dynamics and European temperatures is addressed, based on climate projections of the International Panel on Climate Change. Multi-model analysis, using both flow-analogues and weather regimes methods, show that the inconsistency noticed over recent decades is

  18. Defining response capacity to enhance climate change policy

    International Nuclear Information System (INIS)

    Climate change adaptation and mitigation decisions made by governments are usually taken in different policy domains. At the individual level however, adaptation and mitigation activities are undertaken together as part of the management of risk and resources. We propose that a useful starting point to develop a national climate policy is to understand what societal response might mean in practice. First we frame the set of responses at the national policy level as a trade off between investment in the development and diffusion of new technology, and investment in encouraging and enabling society to change its behaviour and or adopt the new technology. We argue that these are the pertinent trade-offs, rather than those usually posited between climate change mitigation and adaptation. The preference for a policy response that focuses more on technological innovation rather than one that focuses on changing social behaviour will be influenced by the capacity of different societies to change their greenhouse gas emissions; by perceived vulnerability to climate impacts; and by capacity to modify social behaviour and physical environment. Starting with this complete vision of response options should enable policy makers to re-evaluate the risk environment and the set of response options available to them. From here, policy makers should consider who is responsible for making climate response decisions and when actions should be taken. Institutional arrangements dictate social and political acceptability of different policies, they structure worldviews, and they determine the provision of resources for investment in technological innovation and social change. The importance of focussing on the timing of the response is emphasised to maximise the potential for adjustments through social learning and institutional change at different policy scales. We argue that the ability to respond to climate change is both enabled and constrained by social and technological conditions

  19. Explaining continuity and change in international policies: issue linkage, venue change, and learning on policies for the river Scheldt estuary 1967 – 2005

    OpenAIRE

    Meijerink, S.V.

    2008-01-01

    This paper aims to assess the explanatory power and to explore the compatibility of three major accounts of policy continuity and change in cross-border policy domains: negotiation analysis (NA), the advocacy coalition framework (ACF), and the punctuated-equilibrium (PE) framework. These frameworks are used to analyze policies for the river Scheldt estuary between 1967 and 2005. The estuary of the river Scheldt is situated partly in the Belgian region of Flanders and partly in the Netherlands...

  20. Eco-theological Responses to Climate Change in Oceania

    DEFF Research Database (Denmark)

    Rubow, Cecilie; Bird, Cliff

    2016-01-01

    This paper explores eco-theological responses to climate change in Oceania. First, we review central texts in the contextual theological tradition in Oceania, focusing on recent responses to climate change. This points to a body of theological texts integrating climate change into a broader effort...... actors in the cultural modeling of climate change. We highlight the uniqueness of Christian narratives from the Pacific region, while alluding to the fact that literal interpretations of scriptures are influential in many other parts of the world too....

  1. Do competitors modulate rare plant response to precipitation change?

    Science.gov (United States)

    Levine, Jonathan M; McEachern, A Kathryn; Cowan, Clark

    2010-01-01

    Ecologists increasingly suspect that climate change will directly impact species physiology, demography, and phenology, but also indirectly affect these measures via changes to the surrounding community. Unfortunately, few studies examine both the direct and indirect pathways of impact. Doing so is important because altered competitive pressures can reduce or magnify the direct responses of a focal species to climate change. Here, we examine the effects of changing rainfall on three rare annual plant species in the presence and absence of competition on the California Channel Islands. We used rain-out shelters and hand watering to exclude and augment early, late, and season-long rainfall, spanning the wide range of precipitation change forecast for the region. In the absence of competition, droughts reduced the population growth rates of two of three focal annuals, while increased rainfall was only sometimes beneficial. As compared to the focal species, the dominant competitors were more sensitive to the precipitation treatments, benefiting from increased season-long precipitation and harmed by droughts. Importantly, the response of two of three competitors to the precipitation treatments tended to be positively correlated with those of the focal annuals. Although this leads to the expectation that increased competition will counter the direct benefits of favorable conditions, such indirect effects of precipitation change proved weak to nonexistent in our experiment. Competitors had little influence on the precipitation response of two focal species, due to their low sensitivity to competition and highly variable precipitation responses. Competition did affect how our third focal species responded to precipitation change, but this effect only approached significance, and whether it truly resulted from competitor response to precipitation change was unclear. Our work suggests that even when competitors respond to climate change, these responses may have little

  2. ADRENERGIC RESPONSES TO STRESS: TRANSCRIPTIONAL AND POST-TRANSCRIPTIONAL CHANGES

    OpenAIRE

    Wong, Dona L.; Tai, T. C.; Wong-Faull, David C.; Claycomb, Robert; Kvetnansky, Richard

    2008-01-01

    Stress effects on adrenergic responses in rats were examined in adrenal medulla, the primary source of circulating epinephrine (Epi). Irrespective of duration, immobilization (IMMO) increased adrenal corticosterone to the same extent. In contrast, epinephrine changed little, suggesting that Epi synthesis replenishes adrenal pools and sustains circulating levels for the heightened alertness and physiological changes required of the "flight or fight" response. IMMO also induced the epinephrine-...

  3. A comparison of the psychological refractory period and prioritized processing paradigms: Can the response-selection bottleneck model explain them both?

    Science.gov (United States)

    Miller, Jeff; Durst, Moritz

    2015-10-01

    Four experiments examined whether well-established phenomena from the psychological refractory period (PRP) paradigm are also observed in the prioritized processing paradigm, as would be expected from a common description of the 2 paradigms with the response selection bottleneck (RSB) model. Consistent with a generalization of the RSB model to the prioritized processing paradigm, Experiments 1 and 2 showed that this paradigm yields effects of SOA and stimulus discriminability analogous to those observed in the PRP paradigm. In Experiments 3 and 4, however, overall RTs and effect sizes differed between the PRP and prioritized processing paradigms in ways that are difficult to explain within the RSB model. Understanding the differences between these 2 paradigms offers considerable promise as a way to extend the RSB model beyond the domain of the PRP paradigm and to generalize our understanding of multitasking interference.

  4. Coccolithophore calcification response to past ocean acidification and climate change.

    Science.gov (United States)

    O'Dea, Sarah A; Gibbs, Samantha J; Bown, Paul R; Young, Jeremy R; Poulton, Alex J; Newsam, Cherry; Wilson, Paul A

    2014-11-17

    Anthropogenic carbon dioxide emissions are forcing rapid ocean chemistry changes and causing ocean acidification (OA), which is of particular significance for calcifying organisms, including planktonic coccolithophores. Detailed analysis of coccolithophore skeletons enables comparison of calcite production in modern and fossil cells in order to investigate biomineralization response of ancient coccolithophores to climate change. Here we show that the two dominant coccolithophore taxa across the Paleocene-Eocene Thermal Maximum (PETM) OA global warming event (~56 million years ago) exhibited morphological response to environmental change and both showed reduced calcification rates. However, only Coccolithus pelagicus exhibits a transient thinning of coccoliths, immediately before the PETM, that may have been OA-induced. Changing coccolith thickness may affect calcite production more significantly in the dominant modern species Emiliania huxleyi, but, overall, these PETM records indicate that the environmental factors that govern taxonomic composition and growth rate will most strongly influence coccolithophore calcification response to anthropogenic change.

  5. Climate Change Effects on Agriculture: Economic Responses to Biophysical Shocks

    Science.gov (United States)

    Nelson, Gerald C.; Valin, Hugo; Sands, Ronald D.; Havlik, Petr; Ahammad, Helal; Deryng, Delphine; Elliott, Joshua; Fujimori, Shinichiro; Hasegawa, Tomoko; Heyhoe, Edwina

    2014-01-01

    Agricultural production is sensitive to weather and thus directly affected by climate change. Plausible estimates of these climate change impacts require combined use of climate, crop, and economic models. Results from previous studies vary substantially due to differences in models, scenarios, and data. This paper is part of a collective effort to systematically integrate these three types of models. We focus on the economic component of the assessment, investigating how nine global economic models of agriculture represent endogenous responses to seven standardized climate change scenarios produced by two climate and five crop models. These responses include adjustments in yields, area, consumption, and international trade. We apply biophysical shocks derived from the Intergovernmental Panel on Climate Change's representative concentration pathway with end-of-century radiative forcing of 8.5 W/m(sup 2). The mean biophysical yield effect with no incremental CO2 fertilization is a 17% reduction globally by 2050 relative to a scenario with unchanging climate. Endogenous economic responses reduce yield loss to 11%, increase area of major crops by 11%, and reduce consumption by 3%. Agricultural production, cropland area, trade, and prices show the greatest degree of variability in response to climate change, and consumption the lowest. The sources of these differences include model structure and specification; in particular, model assumptions about ease of land use conversion, intensification, and trade. This study identifies where models disagree on the relative responses to climate shocks and highlights research activities needed to improve the representation of agricultural adaptation responses to climate change.

  6. Plant responses to soil heterogeneity and global environmental change

    OpenAIRE

    García-Palacios, Pablo; Maestre, Fernando T.; Bardgett, Richard D.; de Kroon, Hans

    2012-01-01

    Recent evidence suggests that soil nutrient heterogeneity, a ubiquitous feature of terrestrial ecosystems, modulates plant responses to ongoing global change (GC). However, we know little about the overall trends of such responses, the GC drivers involved, and the plant attributes affected.We synthesized literature to answer the question: Does soil heterogeneity significantly affect plant responses to main GC drivers, such as elevated atmospheric carbon dioxide concentration (CO2), nitrogen (...

  7. Forest Owners' Response to Climate Change: University Education Trumps Value Profile.

    Science.gov (United States)

    Blennow, Kristina; Persson, Johannes; Persson, Erik; Hanewinkel, Marc

    2016-01-01

    Do forest owners' levels of education or value profiles explain their responses to climate change? The cultural cognition thesis (CCT) has cast serious doubt on the familiar and often criticized "knowledge deficit" model, which says that laypeople are less concerned about climate change because they lack scientific knowledge. Advocates of CCT maintain that citizens with the highest degrees of scientific literacy and numeracy are not the most concerned about climate change. Rather, this is the group in which cultural polarization is greatest, and thus individuals with more limited scientific literacy and numeracy are more concerned about climate change under certain circumstances than those with higher scientific literacy and numeracy. The CCT predicts that cultural and other values will trump the positive effects of education on some forest owners' attitudes to climate change. Here, using survey data collected in 2010 from 766 private forest owners in Sweden and Germany, we provide the first evidence that perceptions of climate change risk are uncorrelated with, or sometimes positively correlated with, education level and can be explained without reference to cultural or other values. We conclude that the recent claim that advanced scientific literacy and numeracy polarizes perceptions of climate change risk is unsupported by the forest owner data. In neither of the two countries was university education found to reduce the perception of risk from climate change. Indeed in most cases university education increased the perception of risk. Even more importantly, the effect of university education was not dependent on the individuals' value profile. PMID:27223473

  8. Forest Owners' Response to Climate Change: University Education Trumps Value Profile.

    Directory of Open Access Journals (Sweden)

    Kristina Blennow

    Full Text Available Do forest owners' levels of education or value profiles explain their responses to climate change? The cultural cognition thesis (CCT has cast serious doubt on the familiar and often criticized "knowledge deficit" model, which says that laypeople are less concerned about climate change because they lack scientific knowledge. Advocates of CCT maintain that citizens with the highest degrees of scientific literacy and numeracy are not the most concerned about climate change. Rather, this is the group in which cultural polarization is greatest, and thus individuals with more limited scientific literacy and numeracy are more concerned about climate change under certain circumstances than those with higher scientific literacy and numeracy. The CCT predicts that cultural and other values will trump the positive effects of education on some forest owners' attitudes to climate change. Here, using survey data collected in 2010 from 766 private forest owners in Sweden and Germany, we provide the first evidence that perceptions of climate change risk are uncorrelated with, or sometimes positively correlated with, education level and can be explained without reference to cultural or other values. We conclude that the recent claim that advanced scientific literacy and numeracy polarizes perceptions of climate change risk is unsupported by the forest owner data. In neither of the two countries was university education found to reduce the perception of risk from climate change. Indeed in most cases university education increased the perception of risk. Even more importantly, the effect of university education was not dependent on the individuals' value profile.

  9. Forest Owners' Response to Climate Change: University Education Trumps Value Profile

    Science.gov (United States)

    Persson, Erik; Hanewinkel, Marc

    2016-01-01

    Do forest owners’ levels of education or value profiles explain their responses to climate change? The cultural cognition thesis (CCT) has cast serious doubt on the familiar and often criticized "knowledge deficit" model, which says that laypeople are less concerned about climate change because they lack scientific knowledge. Advocates of CCT maintain that citizens with the highest degrees of scientific literacy and numeracy are not the most concerned about climate change. Rather, this is the group in which cultural polarization is greatest, and thus individuals with more limited scientific literacy and numeracy are more concerned about climate change under certain circumstances than those with higher scientific literacy and numeracy. The CCT predicts that cultural and other values will trump the positive effects of education on some forest owners' attitudes to climate change. Here, using survey data collected in 2010 from 766 private forest owners in Sweden and Germany, we provide the first evidence that perceptions of climate change risk are uncorrelated with, or sometimes positively correlated with, education level and can be explained without reference to cultural or other values. We conclude that the recent claim that advanced scientific literacy and numeracy polarizes perceptions of climate change risk is unsupported by the forest owner data. In neither of the two countries was university education found to reduce the perception of risk from climate change. Indeed in most cases university education increased the perception of risk. Even more importantly, the effect of university education was not dependent on the individuals' value profile. PMID:27223473

  10. Forest Owners' Response to Climate Change: University Education Trumps Value Profile.

    Science.gov (United States)

    Blennow, Kristina; Persson, Johannes; Persson, Erik; Hanewinkel, Marc

    2016-01-01

    Do forest owners' levels of education or value profiles explain their responses to climate change? The cultural cognition thesis (CCT) has cast serious doubt on the familiar and often criticized "knowledge deficit" model, which says that laypeople are less concerned about climate change because they lack scientific knowledge. Advocates of CCT maintain that citizens with the highest degrees of scientific literacy and numeracy are not the most concerned about climate change. Rather, this is the group in which cultural polarization is greatest, and thus individuals with more limited scientific literacy and numeracy are more concerned about climate change under certain circumstances than those with higher scientific literacy and numeracy. The CCT predicts that cultural and other values will trump the positive effects of education on some forest owners' attitudes to climate change. Here, using survey data collected in 2010 from 766 private forest owners in Sweden and Germany, we provide the first evidence that perceptions of climate change risk are uncorrelated with, or sometimes positively correlated with, education level and can be explained without reference to cultural or other values. We conclude that the recent claim that advanced scientific literacy and numeracy polarizes perceptions of climate change risk is unsupported by the forest owner data. In neither of the two countries was university education found to reduce the perception of risk from climate change. Indeed in most cases university education increased the perception of risk. Even more importantly, the effect of university education was not dependent on the individuals' value profile.

  11. Climate change and mammals: evolutionary versus plastic responses.

    Science.gov (United States)

    Boutin, Stan; Lane, Jeffrey E

    2014-01-01

    Phenotypic plasticity and microevolution are the two primary means by which organisms respond adaptively to local conditions. While these mechanisms are not mutually exclusive, their relative magnitudes will influence both the rate of, and ability to sustain, phenotypic responses to climate change. We review accounts of recent phenotypic changes in wild mammal populations with the purpose of critically evaluating the following: (i) whether climate change has been identified as the causal mechanism producing the observed change; (ii) whether the change is adaptive; and (iii) the relative influences of evolution and/or phenotypic plasticity underlying the change. The available data for mammals are scant. We found twelve studies that report changes in phenology, body weight or litter size. In all cases, the observed response was primarily due to plasticity. Only one study (of advancing parturition dates in American red squirrels) provided convincing evidence of contemporary evolution. Subsequently, however, climate change has been shown to not be the causal mechanism underlying this shift. We also summarize studies that have shown evolutionary potential (i.e. the trait is heritable and/or under selection) in traits with putative associations with climate change and discuss future directions that need to be undertaken before a conclusive demonstration of plastic or evolutionary responses to climate change in wild mammals can be made. PMID:24454546

  12. Climate engineering research : A precautionary response to climate change?

    NARCIS (Netherlands)

    Reynolds, J.L.; Fleurke, F.M.

    2013-01-01

    In the face of dire forecasts for anthropogenic climate change, climate engineering is increasingly discussed as a possible additional set of responses to reduce climate change’s threat. These proposals have been controversial, in part because they – like climate change itself – pose uncertain risks

  13. A Speeded Item Response Model with Gradual Process Change

    Science.gov (United States)

    Goegebeur, Yuri; De Boeck, Paul; Wollack, James A.; Cohen, Allan S.

    2008-01-01

    An item response theory model for dealing with test speededness is proposed. The model consists of two random processes, a problem solving process and a random guessing process, with the random guessing gradually taking over from the problem solving process. The involved change point and change rate are considered random parameters in order to…

  14. The Evolution of Accounting Theory in Response to Market Changes

    OpenAIRE

    Edwin Quinn Jr.

    2014-01-01

    The purpose of the study is to exam the evolution of accounting theory as a response to changes in the market. The social context of business has changed the historical context of accounting and this study will analyze the relations of to better understand why accounting standards have achieved their present state of evolution.

  15. Corporate responses to climate change: the role of partnerships

    NARCIS (Netherlands)

    A. Kolk; J. Pinkse; L. Hull van Houten

    2010-01-01

    This chapter relates to the NWO-funded research project "‘Getting down to business’: Economic responses to climate change," which studied the (potential) contribution of business to climate change mitigation and adaptation. After an introductory overview of the overall project and its main findings,

  16. Carbon Dynamics in Heathlands in Response to a Changing Climate

    DEFF Research Database (Denmark)

    Nielsen, Pia Lund

    Climate is changing, and more adverse changes are expected in the future. Changes, caused by continuously rising atmospheric concentrations of greenhouse gasses as CO2, will affect ecosystem processes and functions in the future and hence the cycling of carbon. The vaste amount of studies have...... focused on effects of climate change on aboveground biomass, less have been conducted on belowground biomass, and the thesis is one of few studies comprising both above- and belowground biomass and take interactions of climate change factors into account. To follow the fate of carbon in the ecosystem we...... no persistent changes over the years. Responses of aboveground and belowground biomass were coupled, and Deschampsia flexuosa showed high ability to adapt to treatments. As the major response was observed belowground, I further studied decomposition of fine roots. Fine roots of Deschampsia flexuosa from deep...

  17. Responsible Climate Change Adaptation : Exploring, analysing and evaluating public and private responsibilities for urban adaptation to climate change

    OpenAIRE

    Mees, Heleen

    2014-01-01

    Cities are vulnerable to climate change. To deal with climate change, city governments and private actors such as businesses and citizens need to adapt to its effects, such as sea level rise, storm surges, intense rainfall and heatwaves. However, adaptation planning and action is often hampered when the relevant public and private actors have only vague and ambiguous responsibilities. Some exploration on the issue of public and private responsibilities has been undertaken in the literature, b...

  18. Shrinking body size as an ecological response to climate change

    Science.gov (United States)

    Sheridan, Jennifer A.; Bickford, David

    2011-11-01

    Determining how climate change will affect global ecology and ecosystem services is one of the next important frontiers in environmental science. Many species already exhibit smaller sizes as a result of climate change and many others are likely to shrink in response to continued climate change, following fundamental ecological and metabolic rules. This could negatively impact both crop plants and protein sources such as fish that are important for human nutrition. Furthermore, heterogeneity in response is likely to upset ecosystem balances. We discuss future research directions to better understand the trend and help ameliorate the trophic cascades and loss of biodiversity that will probably result from continued decreases in organism size.

  19. Phylogenetic responses of forest trees to global change.

    Directory of Open Access Journals (Sweden)

    John K Senior

    Full Text Available In a rapidly changing biosphere, approaches to understanding the ecology and evolution of forest species will be critical to predict and mitigate the effects of anthropogenic global change on forest ecosystems. Utilizing 26 forest species in a factorial experiment with two levels each of atmospheric CO2 and soil nitrogen, we examined the hypothesis that phylogeny would influence plant performance in response to elevated CO2 and nitrogen fertilization. We found highly idiosyncratic responses at the species level. However, significant, among-genetic lineage responses were present across a molecularly determined phylogeny, indicating that past evolutionary history may have an important role in the response of whole genetic lineages to future global change. These data imply that some genetic lineages will perform well and that others will not, depending upon the environmental context.

  20. Plant community responses to simultaneous changes in temperature, nitrogen availability, and invasion.

    Directory of Open Access Journals (Sweden)

    Elise S Gornish

    Full Text Available Increasing rates of change in climate have been observed across the planet and have contributed to the ongoing range shifts observed for many species. Although ecologists are now using a variety of approaches to study how much and through what mechanisms increasing temperature and nutrient pollution may influence the invasions inherent in range shifts, accurate predictions are still lacking.In this study, we conducted a factorial experiment, simultaneously manipulating warming, nitrogen addition and introduction of Pityopsis aspera, to determine how range-shifting species affect a plant community. We quantified the resident community using ordination scores, then used structural equation modeling to examine hypotheses related to how plants respond to a network of experimental treatments and environmental variables. Variation in soil pH explained plant community response to nitrogen addition in the absence of invasion. However, in the presence of invasion, the direct effect of nitrogen on the community was negligible and soil moisture was important for explaining nitrogen effects. We did not find effects of warming on the native plant community in the absence of invasion. In the presence of invasion, however, warming had negative effects on functional richness directly and invasion and herbivory explained the overall positive effect of warming on the plant community.This work highlights the variation in the biotic and abiotic factors responsible for explaining independent and collective climate change effects over a short time scale. Future work should consider the complex and non-additive relationships among factors of climate change and invasion in order to capture more ecologically relevant features of our changing environment.

  1. Opiate-induced changes in brain adenosine levels and narcotic drug responses.

    Science.gov (United States)

    Wu, M; Sahbaie, P; Zheng, M; Lobato, R; Boison, D; Clark, J D; Peltz, G

    2013-01-01

    We have very little information about the metabolomic changes that mediate neurobehavioral responses, including addiction. It was possible that opioid-induced metabolomic changes in brain could mediate some of the pharmacodynamic effects of opioids. To investigate this, opiate-induced brain metabolomic responses were profiled using a semi-targeted method in C57BL/6 and 129Sv1 mice, which exhibit extreme differences in their tendency to become opiate dependent. Escalating morphine doses (10-40 mg/kg) administered over a 4-day period selectively induced a twofold decrease (pOpiate-induced changes in brain adenosine levels may explain many important neurobehavioral features associated with opiate addiction and withdrawal.

  2. Responsibility for private sector adaptation to climate change

    Directory of Open Access Journals (Sweden)

    Tina Schneider

    2014-06-01

    Full Text Available The Intergovernmental Panel on Climate Change (2007 indicates that vulnerable industries should adapt to the increasing likelihood of extreme weather events along with slowly shifting mean annual temperatures and precipitation patterns, to prevent major damages or periods of inoperability in the future. Most articles in the literature on business management frame organizational adaptation to climate change as a private action. This makes adaptation the sole responsibility of a company, for its sole benefit, and overlooks the fact that some companies provide critical goods and services such a food, water, electricity, and medical care, that are so vital to society that even a short-term setback in operations could put public security at risk. This raises the following questions: (1 Who is responsible for climate change adaptation by private-sector suppliers of critical infrastructure? (2 How can those who are identified to be responsible, actually be held to assume their responsibility for adapting to climate change? These questions will be addressed through a comprehensive review of the literature on business management, complemented by a review of specialized literature on public management. This review leads to several conclusions. Even though tasks that formerly belonged to the state have been taken over by private companies, the state still holds ultimate responsibility in the event of failure of private-sector owned utilities, insofar as they are “critical infrastructure.” Therefore, it remains the state’s responsibility to foster adaptation to climate change with appropriate action. In theory, effective ways of assuming this responsibility, while enabling critical infrastructure providers the flexibility adapt to climate change, would be to delegate adaptation to an agency, or to conduct negotiations with stakeholders. In view of this theory, Germany will be used as a case study to demonstrate how private-sector critical

  3. Complex response of the forest nitrogen cycle to climate change.

    Science.gov (United States)

    Bernal, Susana; Hedin, Lars O; Likens, Gene E; Gerber, Stefan; Buso, Don C

    2012-02-28

    Climate exerts a powerful influence on biological processes, but the effects of climate change on ecosystem nutrient flux and cycling are poorly resolved. Although rare, long-term records offer a unique opportunity to disentangle effects of climate from other anthropogenic influences. Here, we examine the longest and most complete record of watershed nutrient and climate dynamics available worldwide, which was collected at the Hubbard Brook Experimental Forest in the northeastern United States. We used empirical analyses and model calculations to distinguish between effects of climate change and past perturbations on the forest nitrogen (N) cycle. We find that climate alone cannot explain the occurrence of a dramatic >90% drop in watershed nitrate export over the past 46 y, despite longer growing seasons and higher soil temperatures. The strongest climate influence was an increase in soil temperature accompanied by a shift in paths of soil water flow within the watershed, but this effect explained, at best, only ∼40% of the nitrate decline. In contrast, at least 50-60% of the observed change in the N export could be explained by the long-lasting effect of forest cutting in the early 1900s on the N cycle of the soil and vegetation pools. Our analysis shows that historic events can obscure the influence of modern day stresses on the N cycle, even when analyses have the advantage of being informed by 0.5-century-long datasets. These findings raise fundamental questions about interpretations of long-term trends as a baseline for understanding how climate change influences complex ecosystems. PMID:22331889

  4. Response-reinforcer relations and resistance to change.

    Science.gov (United States)

    Podlesnik, Christopher A; Shahan, Timothy A

    2008-01-01

    Behavioral momentum theory suggests that the relation between a response and a reinforcer (i.e., response-reinforcer relation) governs response rates and the relation between a stimulus and a reinforcer (i.e., stimulus-reinforcer relation) governs resistance to change. The present experiments compared the effects degrading response-reinforcer relations with response-independent or delayed reinforcers on resistance to change in conditions with equal stimulus-reinforcer relations. In Experiment 1, pigeons responded on equal variable-interval schedules of immediate reinforcement in three components of a multiple schedule. Additional response-independent reinforcers were available in one component and additional delayed reinforcers were available in another component. The results showed that resistance to disruption was greater in the components with added reinforcers than without them (i.e., better stimulus-reinforcer relations), but did not differ for the components with added response-independent and delayed reinforcement. In Experiment 2, a component presenting immediate reinforcement alternated with either a component that arranged equal rates of reinforcement with a proportion of those reinforcers being response independent or a component with a proportion of the reinforcers being delayed. Results showed that resistance to disruption tended to be either similar across components or slightly lower when response-reinforcer relations were degraded with either response-independent or delayed reinforcers. These findings suggest that degrading response-reinforcer relations can impact resistance to change, but that impact does not depend on the specific method and is small relative to the effects of the stimulus-reinforcer relation. PMID:17706897

  5. Response-reinforcer relations and resistance to change.

    Science.gov (United States)

    Podlesnik, Christopher A; Shahan, Timothy A

    2008-01-01

    Behavioral momentum theory suggests that the relation between a response and a reinforcer (i.e., response-reinforcer relation) governs response rates and the relation between a stimulus and a reinforcer (i.e., stimulus-reinforcer relation) governs resistance to change. The present experiments compared the effects degrading response-reinforcer relations with response-independent or delayed reinforcers on resistance to change in conditions with equal stimulus-reinforcer relations. In Experiment 1, pigeons responded on equal variable-interval schedules of immediate reinforcement in three components of a multiple schedule. Additional response-independent reinforcers were available in one component and additional delayed reinforcers were available in another component. The results showed that resistance to disruption was greater in the components with added reinforcers than without them (i.e., better stimulus-reinforcer relations), but did not differ for the components with added response-independent and delayed reinforcement. In Experiment 2, a component presenting immediate reinforcement alternated with either a component that arranged equal rates of reinforcement with a proportion of those reinforcers being response independent or a component with a proportion of the reinforcers being delayed. Results showed that resistance to disruption tended to be either similar across components or slightly lower when response-reinforcer relations were degraded with either response-independent or delayed reinforcers. These findings suggest that degrading response-reinforcer relations can impact resistance to change, but that impact does not depend on the specific method and is small relative to the effects of the stimulus-reinforcer relation.

  6. Global Change and Regional Landscape Response and Desertification in Siberia

    Institute of Scientific and Technical Information of China (English)

    V.M. PLYUSNIN; L.V. DANKO

    2011-01-01

    Climate changes and associated natural and anthropogenic processes have manifested themselves particularly clearly during the last two decades.The study of consequences of these changes has become one of the central scientific,social and political issues of our time (Pilot 2000;UNEP 2007).The study of the regional response of landscapes of Siberia to global changes is one of the fundamental tasks,aimed at ensuring the sustainable development of Siberian regions both at present time and in the future.Because in the 21 st century we should expect strong changes the humidity regime,accompanying the global warming (CCD 1994).

  7. Methane emission through ebullition from an estuarine mudflat: 1. A conceptual model to explain tidal forcing based on effective stress changes

    Science.gov (United States)

    Chen, Xi; Slater, Lee

    2016-06-01

    Ebullition is an important pathway for transport of methane (CH4) to the atmosphere in wetlands. Water level changes have been suggested to trigger ebullition, especially in tidally flooded areas, although the controlling mechanisms remain uncertain. Bubble transport in submerged sediment represents a multiphase, dynamic interaction between gaseous and solid phases under the modulation of a liquid phase. An unvegetated sediment monolith was retrieved from an estuarine mudflat area at a tidal marsh site and maintained in a saturated state. Laboratory measurements on the mud monolith confirmed that not only ebbing tides, but also flooding tides could trigger ebullition releases of gas bubbles. We develop a Changing Stress for Simulating Ebullition (CSSE) model to describe mechanisms controlling bubble expansion in response to water level changes to unify these observations. Decreases in water level are assumed to lower the effective stress surrounding isolated trapped gas bubbles, driving upward transport via bubble expansion and deformation, with associated fracturing of overlying sediments. Increases in relative permittivity suggest that additional water invades macropores, with associated pore expansion, during the initial stage of increases in water level. We propose that subsequent matrix expansion under lowered effective stress on rising tides also leads to fracture propagation and bubble release. Our findings demonstrate the importance of effective stress changes in triggering ebullition from mudflat areas in tidal wetlands, modulated by the mechanical properties of shallow soft sediments.

  8. Prepulse inhibition of auditory change-related cortical responses

    Directory of Open Access Journals (Sweden)

    Inui Koji

    2012-10-01

    Full Text Available Abstract Background Prepulse inhibition (PPI of the startle response is an important tool to investigate the biology of schizophrenia. PPI is usually observed by use of a startle reflex such as blinking following an intense sound. A similar phenomenon has not been reported for cortical responses. Results In 12 healthy subjects, change-related cortical activity in response to an abrupt increase of sound pressure by 5 dB above the background of 65 dB SPL (test stimulus was measured using magnetoencephalography. The test stimulus evoked a clear cortical response peaking at around 130 ms (Change-N1m. In Experiment 1, effects of the intensity of a prepulse (0.5 ~ 5 dB on the test response were examined using a paired stimulation paradigm. In Experiment 2, effects of the interval between the prepulse and test stimulus were examined using interstimulus intervals (ISIs of 50 ~ 350 ms. When the test stimulus was preceded by the prepulse, the Change-N1m was more strongly inhibited by a stronger prepulse (Experiment 1 and a shorter ISI prepulse (Experiment 2. In addition, the amplitude of the test Change-N1m correlated positively with both the amplitude of the prepulse-evoked response and the degree of inhibition, suggesting that subjects who are more sensitive to the auditory change are more strongly inhibited by the prepulse. Conclusions Since Change-N1m is easy to measure and control, it would be a valuable tool to investigate mechanisms of sensory gating or the biology of certain mental diseases such as schizophrenia.

  9. Contrasting responses of urban and rural surface energy budgets to heat waves explain synergies between urban heat islands and heat waves

    International Nuclear Information System (INIS)

    Heat waves (HWs) are projected to become more frequent and last longer over most land areas in the late 21st century, which raises serious public health concerns. Urban residents face higher health risks due to synergies between HWs and urban heat islands (UHIs) (i.e., UHIs are higher under HW conditions). However, the responses of urban and rural surface energy budgets to HWs are still largely unknown. This study analyzes observations from two flux towers in Beijing, China and reveals significant differences between the responses of urban and rural (cropland) ecosystems to HWs. It is found that UHIs increase significantly during HWs, especially during the nighttime, implying synergies between HWs and UHIs. Results indicate that the urban site receives more incoming shortwave radiation and longwave radiation due to HWs as compared to the rural site, resulting in a larger radiative energy input into the urban surface energy budget. Changes in turbulent heat fluxes also diverge strongly for the urban site and the rural site: latent heat fluxes increase more significantly at the rural site due to abundant available water, while sensible heat fluxes and possibly heat storage increase more at the urban site. These comparisons suggest that the contrasting responses of urban and rural surface energy budgets to HWs are responsible for the synergies between HWs and UHIs. As a result, urban mitigation and adaption strategies such as the use of green roofs and white roofs are needed in order to mitigate the impact of these synergies. (letter)

  10. Contrasting responses of urban and rural surface energy budgets to heat waves explain synergies between urban heat islands and heat waves

    Science.gov (United States)

    Li, Dan; Sun, Ting; Liu, Maofeng; Yang, Long; Wang, Linlin; Gao, Zhiqiu

    2015-05-01

    Heat waves (HWs) are projected to become more frequent and last longer over most land areas in the late 21st century, which raises serious public health concerns. Urban residents face higher health risks due to synergies between HWs and urban heat islands (UHIs) (i.e., UHIs are higher under HW conditions). However, the responses of urban and rural surface energy budgets to HWs are still largely unknown. This study analyzes observations from two flux towers in Beijing, China and reveals significant differences between the responses of urban and rural (cropland) ecosystems to HWs. It is found that UHIs increase significantly during HWs, especially during the nighttime, implying synergies between HWs and UHIs. Results indicate that the urban site receives more incoming shortwave radiation and longwave radiation due to HWs as compared to the rural site, resulting in a larger radiative energy input into the urban surface energy budget. Changes in turbulent heat fluxes also diverge strongly for the urban site and the rural site: latent heat fluxes increase more significantly at the rural site due to abundant available water, while sensible heat fluxes and possibly heat storage increase more at the urban site. These comparisons suggest that the contrasting responses of urban and rural surface energy budgets to HWs are responsible for the synergies between HWs and UHIs. As a result, urban mitigation and adaption strategies such as the use of green roofs and white roofs are needed in order to mitigate the impact of these synergies.

  11. Market effects of changes in consumers' social responsibility

    OpenAIRE

    García Gallego, Aurora; Georgantzis, Nikolaos

    2009-01-01

    In a duopoly model of vertical differentiation, we study market equilibrium and the resulting social welfare following an increase in the consumer's willingness to pay (WTP) for products sold by socially responsible manufacturers. Different types of such changes emerge depending on their effects on consumer heterogeneity. We show that, in most cases, increases in the consumers' social consciousness yield higher profits to socially responsible firms and may lead to higher levels of social welf...

  12. Belowground responses to elevation in a changing cloud forest.

    Science.gov (United States)

    Looby, Caitlin I; Maltz, Mia R; Treseder, Kathleen K

    2016-04-01

    Few studies have investigated how soil fungal communities respond to elevation, especially within TMCF (tropical montane cloud forests). We used an elevation gradient in a TMCF in Costa Rica to determine how soil properties, processes, and community composition of fungi change in response to elevation and across seasons. As elevation increased, soil temperature and soil pH decreased, while soil moisture and soil C:N ratios increased with elevation. Responses of these properties varied seasonally. Fungal abundance increased with elevation during wet and dry seasons. Fungal community composition shifted in response to elevation, and to a lesser extent by season. These shifts were accompanied by varying responses of important fungal functional groups during the wet season and the relative abundance of certain fungal phyla. We suggest that elevation and the responses of certain fungal functional groups may be structuring fungal communities along this elevation gradient. TMCF are ecosystems that are rapidly changing due to climate change. Our study suggests that these changes may affect how fungal communities are structured. PMID:27066220

  13. Adaptive thermoregulation in endotherms may alter responses to climate change.

    Science.gov (United States)

    Boyles, Justin G; Seebacher, Frank; Smit, Ben; McKechnie, Andrew E

    2011-11-01

    Climate change is one of the major issues facing natural populations and thus a focus of recent research has been to predict the responses of organisms to these changes. Models are becoming more complex and now commonly include physiological traits of the organisms of interest. However, endothermic species have received less attention than have ectotherms in these mechanistic models. Further, it is not clear whether responses of endotherms to climate change are modified by variation in thermoregulatory characteristics associated with phenotypic plasticity and/or adaptation to past selective pressures. Here, we review the empirical data on thermal adaptation and acclimatization in endotherms and discuss how those factors may be important in models of responses to climate change. We begin with a discussion of why thermoregulation and thermal sensitivity at high body temperatures should be co-adapted. Importantly, we show that there is, in fact, considerable variation in the ability of endotherms to tolerate high body temperatures and/or high environmental temperatures, but a better understanding of this variation will likely be critical for predicting responses to future climatic scenarios. Next, we discuss why variation in thermoregulatory characteristics should be considered when modeling the effects of climate change on heterothermic endotherms. Finally, we review some biophysical and biochemical factors that will limit adaptation and acclimation in endotherms. We consider both long-term, directional climate change and short-term (but increasingly common) anomalies in climate such as extreme heat waves and we suggest areas of important future research relating to both our basic understanding of endothermic thermoregulation and the responses of endotherms to climate change.

  14. A probabilistic model of ecosystem response to climate change

    International Nuclear Information System (INIS)

    Anthropogenic activities are leading to rapid changes in land cover and emissions of greenhouse gases into the atmosphere. These changes can bring about climate change typified by average global temperatures rising by 1--5 C over the next century. Climate change of this magnitude is likely to alter the distribution of terrestrial ecosystems on a large scale. Options available for dealing with such change are abatement of emissions, adaptation, and geoengineering. The integrated assessment of climate change demands that frameworks be developed where all the elements of the climate problem are present (from economic activity to climate change and its impacts on market and non-market goods and services). Integrated climate assessment requires multiple impact metrics and multi-attribute utility functions to simulate the response of different key actors/decision-makers to the actual physical impacts (rather than a dollar value) of the climate-damage vs. policy-cost debate. This necessitates direct modeling of ecosystem impacts of climate change. The authors have developed a probabilistic model of ecosystem response to global change. This model differs from previous efforts in that it is statistically estimated using actual ecosystem and climate data yielding a joint multivariate probability of prevalence for each ecosystem, given climatic conditions. The authors expect this approach to permit simulation of inertia and competition which have, so far, been absent in transfer models of continental-scale ecosystem response to global change. Thus, although the probability of one ecotype will dominate others at a given point, others would have the possibility of establishing an early foothold

  15. Behaviour and climate change : consumer perceptions of responsibility.

    OpenAIRE

    Wells, V.K.; Ponting, C.; Peattie, K.

    2011-01-01

    This paper explores the under-researched notion of consumer responsibility, a potentially significant influence on consumer behaviour that marketers and policymakers may be able to harness as they attempt to respond to environmental challenges such as climate change. The paper uses data derived from a commercially motivated survey (n = 1513) to explore domestic consumption behaviours most closely associated with the issue of disruptive climate change. A measure of 'General Environmental Respo...

  16. Public health responses to climate change health impacts in Indonesia.

    Science.gov (United States)

    Wirawan, I Made Ady

    2010-01-01

    Although climate change is a global concern, there are particular considerations for Indonesia as an archipelagic nation. These include the vulnerability of people living in small islands and coastal areas to rising sea levels; the expansion of the important mosquito-borne diseases, particularly malaria and dengue, into areas that lack of immunity; and the increase in water-borne diseases and malnutrition. This article proposes a set of public health responses to climate change health impacts in Indonesia. Some important principles and practices in public health are highlighted, to develop effective public health approaches to climate change in Indonesia. PMID:20032032

  17. Individual and Collective Responsiveness to Climate Change: A Response to Dwyer

    Directory of Open Access Journals (Sweden)

    Macpherson, Cheryl C

    2016-01-01

    Full Text Available James Dwyer’s story about a fictional GAIA Commission highlighted unresolved concerns about the scope of bioethics, specifically regarding the global distribution of, and responsibility for, the health impacts of climate change. This commentary discusses the potential impact of an individual on greenhouse gas emissions and the importance of engaging institutional responses in order to have meaningful impacts.

  18. On the response of valley glaciers to climatic change

    NARCIS (Netherlands)

    Oerlemans, J.

    1989-01-01

    In many cases the response of a glacier to changing climatic conditions is complicated due to the large number of feedback loops that play a role. Examples are: ice thickness - mass balance feedback, nonlinearities arising from complicated geometry, dependence of ablation on glacier geometry, coupli

  19. Idiosyncratic responses of high Arctic plants to changing snow regimes.

    Science.gov (United States)

    Rumpf, Sabine B; Semenchuk, Philipp R; Dullinger, Stefan; Cooper, Elisabeth J

    2014-01-01

    The Arctic is one of the ecosystems most affected by climate change; in particular, winter temperatures and precipitation are predicted to increase with consequent changes to snow cover depth and duration. Whether the snow-free period will be shortened or prolonged depends on the extent and temporal patterns of the temperature and precipitation rise; resulting changes will likely affect plant growth with cascading effects throughout the ecosystem. We experimentally manipulated snow regimes using snow fences and shoveling and assessed aboveground size of eight common high arctic plant species weekly throughout the summer. We demonstrated that plant growth responded to snow regime, and that air temperature sum during the snow free period was the best predictor for plant size. The majority of our studied species showed periodic growth; increases in plant size stopped after certain cumulative temperatures were obtained. Plants in early snow-free treatments without additional spring warming were smaller than controls. Response to deeper snow with later melt-out varied between species and categorizing responses by growth forms or habitat associations did not reveal generic trends. We therefore stress the importance of examining responses at the species level, since generalized predictions of aboveground growth responses to changing snow regimes cannot be made.

  20. Idiosyncratic responses of high Arctic plants to changing snow regimes.

    Directory of Open Access Journals (Sweden)

    Sabine B Rumpf

    Full Text Available The Arctic is one of the ecosystems most affected by climate change; in particular, winter temperatures and precipitation are predicted to increase with consequent changes to snow cover depth and duration. Whether the snow-free period will be shortened or prolonged depends on the extent and temporal patterns of the temperature and precipitation rise; resulting changes will likely affect plant growth with cascading effects throughout the ecosystem. We experimentally manipulated snow regimes using snow fences and shoveling and assessed aboveground size of eight common high arctic plant species weekly throughout the summer. We demonstrated that plant growth responded to snow regime, and that air temperature sum during the snow free period was the best predictor for plant size. The majority of our studied species showed periodic growth; increases in plant size stopped after certain cumulative temperatures were obtained. Plants in early snow-free treatments without additional spring warming were smaller than controls. Response to deeper snow with later melt-out varied between species and categorizing responses by growth forms or habitat associations did not reveal generic trends. We therefore stress the importance of examining responses at the species level, since generalized predictions of aboveground growth responses to changing snow regimes cannot be made.

  1. RESPONSE AND FEEDBACKS OF FOREST ECOSYSTEMS TO GLOBAL CLIMATE CHANGE

    Science.gov (United States)

    The accumulation of greenhouse gases in the atmosphere over the past century is projected to cause a warming of the Earth. Climate Change predictions vary by region and terrestrial biosphere response, and feedbacks will be ecosystem specific. Forests play a major role in the Eart...

  2. RESPONSES AND FEEDBACK TO GLOBAL FORESTS TO CLIMATE CHANGE

    Science.gov (United States)

    The accumulation of greenhouse gases in the atmosphere over the past century is projected to cause a warming of the Earth. limate change predictions vary by region and terrestrial biosphere response and feedbacks will be ecosystem specific. orests play a major role in the earth's...

  3. Do familiarity and expectations change perception? Drivers’ glances and response to changes

    NARCIS (Netherlands)

    Martens, M.H.; Fox, M.

    2007-01-01

    The present study shows that repeated exposure to a road environment changes eye movement behaviour. In addition, repeated exposure may result in inadequate responses to unexpected changes in the road environment. Participants drove a low-cost simulator while their eye movements were recorded. With

  4. Thermal sensation and thermophysiological responses with metabolic step-changes

    DEFF Research Database (Denmark)

    Goto, Tomonobu; Toftum, Jørn; deDear, Richard;

    2006-01-01

    This study investigated the effect on thermal perception and thermophysiological variables of controlled metabolic excursions of various intensities and durations. Twenty-four subjects alternately were seated on a chair or exercised by walking on a treadmill at a temperature predicted to be neutral...... at sedentary activity. In a second experimental series, subjects alternated between rest and exercise as well as between exercise at different intensities at two temperature levels. Measurements comprised skin and oesophageal temperatures, heart rate and subjective responses. Thermal sensation started to rise...... or decline immediately (within one minute) after a change of activity, which means that even moderate activity changes of short duration affect thermal perceptions of humans. After approximately 15-20 min under constant activity subjective thermal responses approximated the steady-state response...

  5. Explaining Simulations Through Self Explaining Agents

    OpenAIRE

    Maaike Harbers; John-Jules Meyer; Karel Van den Bosch

    2010-01-01

    Several strategies are used to explain emergent interaction patterns in agent-based simulations. A distinction can be made between simulations in which the agents just behave in a reactive way, and simulations involving agents with also pro-active (goal-directed) behavior. Pro-active behavior is more variable and harder to predict than reactive behavior, and therefore it might be harder to explain. However, the approach presented in this paper tries to make advantage of the agents' pro-active...

  6. Long-term ecophysiological responses to climate change

    DEFF Research Database (Denmark)

    Boesgaard, Kristine Stove; Ro-Poulsen, Helge

    Plant physiology is affected by climate change. Acclimations of photosynthetic processes are induced by short-term changes in climatic conditions. Further acclimation can be caused by longterm adjustments to climate change due to ecosystem-feedbacks. The aim of this PhD was to investigate plant...... are stable upon a wide range of seasonal and inter-annual variation. Longterm ecosystem adjustments after 6 years of treatments did not cause further physiological acclimation in either Deschampsia or Calluna. The study indicates robustness of the Danish heathland ecosystem to moderate climate change....... physiological responses to climate change in a seasonal and long-term perspective. The effects of elevated CO2, passive night time warming and periodic summer drought as single factor and in combination, on plant physiology were investigated in the long-term multifactorial field experiment CLIMAITE in a Danish...

  7. Baroreflex Responses to Acute Changes in Blood Volume in Humans

    Science.gov (United States)

    Thompson, Cynthia A.; Tatro, Dana L.; Ludwig, David A.; Convertino, Victor A.

    1990-01-01

    To test the hypothesis that acute changes in plasma volume affect the stimulus-response relations of high- and low- pressure baroreflexes, eight men (27-44 yr old) underwent measurements for carotid-cardiac and cardiopulmonary baro- reflex responses under the following three volemic conditions: hypovolemic, normovolemic, and hypervolemic. The stimulus- response relation of the carotid-cardiac response curve was generated using a neck cuff device, which delivered pressure changes between +40 and -65 mmHg in continuous steps of 15 mmHg. The stimulus-response relationships of the cardiopulmonary baroreflex were studied by measurements of Forearm Vascular Resistance (FVR) and Peripheral Venotis Pressure (PVP) during low levels of lower body negative pressure (O to -20 mmHg). Altered vascular volume had no effect on response relations of the carotid-cardiac baroreflex but did alter the gain of the cardiopulmonary baroreflex (-7.93 q 1.71, -4.36 q 1.38, and -2.56 q 1.59 peripheral resistance units/mmHg for hypovolemic, normovolemic, and hypervolemic, respectively) independent of shifts in baseline FVR and PVP. These results indicate greater demand for vasoconstriction for equal reductions in venous pressure during progressive hypovolemia; this condition may compromise the capacity to provide adequate peripheral resistance during severe orthostatic stress. Fluid loading before reentry after spaceflight may act to restore vasoconstrictive capacity of the cardiopulnionary baroreflex but may not be an effective countermeasure against potential post- flight impairment of the carotid-cardiac baroreflex.

  8. Studies on climate change problems and response measures in China

    International Nuclear Information System (INIS)

    Climate has substantial influence on the development of human society. At the same time, the global climate is being affected by human activities. Since industrial revolution large amount of CO2 and other greenhouse gases have been emitted to the atmosphere, causing significant change in its composition. It is recognized that this change might be sufficient to cause change in global climate. Because of the importance of climate change issues, the Chinese government pays great attention to them. As climate change concerns almost all aspects of the social and economic development, in order to coordinate ministries and agencies of the government in their efforts to deal with climate change problems, the Coordinating Group on Climate Change under the Environmental Protection Committee of the State Council was established in February 1990. There are four working groups under the Coordinating Group, working on scientific assessment, impact assessment and response strategies, economic implication and international convention matters of climate change. A number of research and technological development projects related to climate change issues have been organized, including bilateral cooperation projects and projects supported by GEF, UNEP, UNDP, the World Bank, the Asian Development Bank and other international organizations. (EG) 11 refs

  9. Leaf Stomatal Responses to Vapour Pressure Deficit Under Current and CO2- Enriched Atmosphere Explained by the Economics of gas Exchange

    Science.gov (United States)

    Palmroth, S.; Katul, G. G.; Oren, R.

    2008-12-01

    Climate models predict that warming caused by increasing atmospheric greenhouse gases will not be accompanied with a change in atmospheric relative humidity (RH) but will cause an exponential increase in vapor pressure deficit (D). Predictions of water cycling in future climates are sensitive to the response of stomatal conductance (g) to all these changes. In currently used ecosystem models, the simulation of CO2 and water vapor exchange through stomata is typically based on empirical or semi-empirical stomatal responses to environmental stimuli. Depending on the formulation, stomata respond to either D or RH and, consequently, g predicted under future climate scenarios will greatly differ. In difference to the semi- empirical formulations of g, the tradeoffs between leaf-level carbon gain in photosynthesis and water loss in transpiration can be analyzed using the economics of gas exchange. First presented by Cowan (1977) and Cowan and Farquhar (1977; hereafter CF77) and reformulated by Berninger and Hari (1993; hereafter BH93), the cost (water loss) to benefit (carbon gain) analysis was framed as an economic optimization where the daily carbon gain is maximized for a given loss of water. While the assumptions on the form of the underlying functions differ between CF77 and BH93, we show that the optimal solutions can be made identical where the solution is independent of the time scale of flux integration. The stomatal control over gas exchange is described through a concept of invariant 'cost of water', without a priori specification of stomatal response to D or atmospheric CO2. The expressions are "emergent properties" of the optimization theory. These emergent responses are compared with data from studies from a wide range of conditions and are shown to be consistent with (1) the onset of an apparent "feed-forward" mechanism, (2) the sensitivity of stomatal conductance to D, and (3) the nonlinear variation in intercellular CO2 concentration with increasing D

  10. Stratospheric Response to Intraseasonal Changes in Incoming Solar Radiation

    Science.gov (United States)

    Garfinkel, Chaim; silverman, vered; harnik, nili; Erlich, caryn

    2016-04-01

    Superposed epoch analysis of meteorological reanalysis data is used to demonstrate a significant connection between intraseasonal solar variability and temperatures in the stratosphere. Decreasing solar flux leads to a cooling of the tropical upper stratosphere above 7hPa, while increasing solar flux leads to a warming of the tropical upper stratosphere above 7hPa, after a lag of approximately six to ten days. Late winter (February-March) Arctic stratospheric temperatures also change in response to changing incoming solar flux in a manner consistent with that seen on the 11 year timescale: ten to thirty days after the start of decreasing solar flux, the polar cap warms during the easterly phase of the Quasi-Biennal Oscillation. In contrast, cooling is present after decreasing solar flux during the westerly phase of the Quasi-Biennal Oscillation (though it is less robust than the warming during the easterly phase). The estimated composite mean changes in Northern Hemisphere upper stratospheric (~ 5hPa) polar temperatures exceed 8K, and are potentially a source of intraseasonal predictability for the surface. These changes in polar temperature are consistent with the changes in wave driving entering the stratosphere. Garfinkel, C.I., V. Silverman, N. Harnik, C. Erlich, Y. Riz (2015), Stratospheric Response to Intraseasonal Changes in Incoming Solar Radiation, J. Geophys. Res. Atmos., 120, 7648-7660. doi: 10.1002/2015JD023244.

  11. A climate response function explaining most of the variation in the forest floor needle mass and the needle decomposition in pine forests across Europe

    DEFF Research Database (Denmark)

    Kurz-Besson, C.; Coûteaux, M.M.; Berg, Bjørn;

    2006-01-01

    and a recalcitrant one. NF was correlated with actual evapotranspiration (AET) whereas the decomposition parameters (decomposition rate of the decomposable fraction, first year mass loss, forest floor needle mass, age of the most-decomposed category) were related to a combined response function to climate (CRF......The forest floor needle mass and the decomposition rates of pine needle litter in a European climate transect were studied in order to estimate the impact of climate change on forest soil carbon sequestration. Eight pine forests preserved from fire were selected along a climatic latitudinal...... gradient from 40° to 60° N, from Spain and Portugal to Sweden. The forest floor (Oi and Oe layers) was sorted into five categories of increasing decomposition level according to morphological criteria. The needle mass loss in each category was determined using a linear mass density method. The needle...

  12. Baroreflex Responses to Acute Changes in Blood Volume in Humans

    Science.gov (United States)

    Thompson, Cynthia A.; Tatro, Dana L.; Ludwig, David A.; Convertino, Victor A.

    1990-01-01

    To test the hypothesis that acute changes in plasma volume affect the stimulus-response relations of high- and low- pressure baroreflexes, eight men (27-44 yr old) underwent measurements for carotid-cardiac and cardiopulmonary baro-reflex responses under the following three volemic conditions: hypovolemic, normovolemic, and hypervolemic. The stimulus- response relation of the carotid-cardiac response curve was generated using a neck cuff device, which delivered pressure changes between +40 and -65 mmHg in continuous steps of 15 mmHg. The stimulus-response relationship, of the cardio-pulmonary baroreflex were studied by measurements of Forearm Vascular Resistance (FVR) and Peripheral Venous Pressure (PVP) during low levels of lower body negative pressure (O to -20 mmHg). The results indicate greater demand for vasoconstriction for equal reductions in venous pressure during progressive hypovolemia; this condition may compromise the capacity to provide adequate peripheral resistance during severe orthostatic stress. Fluid loading before reentry after spaceflight may act to restore vasoconstrictive capacity of the cardiopulmonary baroreflex but may not be an effective countermeasure against potential post- flight impairment of the carotid-cardiac baroreflex.

  13. Dynamic brain mapping of behavior change: tracking response initiation and inhibition to changes in reinforcement rate.

    Science.gov (United States)

    Schlund, Michael W; Magee, Sandy; Hudgins, Caleb D

    2012-10-01

    Adaptive behavior change is supported by executive control processes distributed throughout a prefrontal-striatal-parietal network. Yet, the temporal dynamics of regions in the network have not been characterized. Using functional magnetic resonance imaging (fMRI), we tracked changes brain activation while subjects initiated and inhibited responding in accordance with changes in reinforcement rate. During imaging, subjects completed a free-operant task that involved repeated transitions between fixed-ratio reinforcement and extinction (RF:EXT), where reinforcement rate decreased and responding was inhibited, and between extinction and fixed-ratio reinforcement (EXT:RF), where reinforcement rate increased and responding was initiated. Our whole-brain temporal assessment revealed that transitions which required initiating and inhibiting responding prompted positive phasic responses in a prefrontal-parietal network, the insula and thalamus. However, response initiation prompted by an increase in reinforcement rate during the EXT:RF transition elicited positive phasic responses in reward-sensitive striatal regions. Furthermore, response inhibition prompted by a decrease in reinforcement rate during the RF:EXT transition elicited negative phasic responses in ventral frontal regions sensitive to value and contingency. Our findings highlight the temporal dynamics of a brain network that supports behavioral changes (initiation and inhibition) resulting from changes in local reinforcement rates.

  14. Physician response to fee changes with multiple payers.

    Science.gov (United States)

    McGuire, T G; Pauly, M V

    1991-01-01

    This paper develops a general model of physician behavior with demand inducement encompassing the two benchmark cases of profit maximization and target-income behavior. It is shown that when income effects are absent, physicians maximize profits, and when income effects are very strong, physicians seek a target income. The model is used to derive own and cross-price expressions for the response of physicians to fee changes in the realistic context of more than one payer under the alternative behavior assumptions of profit maximization and target income behavior. The implications for public and private fee policy, and empirical research on physician response to fees, are discussed. PMID:10117011

  15. Key ecological responses to nitrogen are altered by climate change

    Science.gov (United States)

    Greaver, T.L.; Clark, C.M.; Compton, J.E.; Vallano, D.; Talhelm, A. F.; Weaver, C.P.; Band, L.E.; Baron, J. S.; Davidson, E.A.; Tague, C.L.; Felker-Quinn, E.; Lynch, J.A.; Herrick, J.D.; Liu, L.; Goodale, C.L.; Novak, K. J.; Haeuber, R. A.

    2016-01-01

    Climate change and anthropogenic nitrogen deposition are both important ecological threats. Evaluating their cumulative effects provides a more holistic view of ecosystem vulnerability to human activities, which would better inform policy decisions aimed to protect the sustainability of ecosystems. Our knowledge of the cumulative effects of these stressors is growing, but we lack an integrated understanding. In this Review, we describe how climate change alters key processes in terrestrial and freshwater ecosystems related to nitrogen cycling and availability, and the response of ecosystems to nitrogen addition in terms of carbon cycling, acidification and biodiversity.

  16. Western Mountain Initiative: predicting ecosystem responses to climate change

    Science.gov (United States)

    Baron, Jill S.; Peterson, David L.; Wilson, J.T.

    2008-01-01

    Mountain ecosystems of the western United States provide irreplaceable goods and services such as water, timber, biodiversity, and recreational opportunities, but their responses to climatic changes are complex and not well understood. The Western Mountain Initiative (WMI), a collaboration between USGS and U.S. Forest Service scientists, catalyzes assessment and synthesis of the effects of disturbance and climate change across western mountain areas, focusing on national parks and surrounding national forests. The WMI takes an ecosystem approach to science, integrating research across science disciplines at scales ranging from field studies to global trends.

  17. Climate change in the oceans: Human impacts and responses

    Science.gov (United States)

    Allison, Edward H.; Bassett, Hannah R.

    2015-11-01

    Although it has far-reaching consequences for humanity, attention to climate change impacts on the ocean lags behind concern for impacts on the atmosphere and land. Understanding these impacts, as well as society’s diverse perspectives and multiscale responses to the changing oceans, requires a correspondingly diverse body of scholarship in the physical, biological, and social sciences and humanities. This can ensure that a plurality of values and viewpoints is reflected in the research that informs climate policy and may enable the concerns of maritime societies and economic sectors to be heard in key adaptation and mitigation discussions.

  18. Climate change in the oceans: Human impacts and responses.

    Science.gov (United States)

    Allison, Edward H; Bassett, Hannah R

    2015-11-13

    Although it has far-reaching consequences for humanity, attention to climate change impacts on the ocean lags behind concern for impacts on the atmosphere and land. Understanding these impacts, as well as society's diverse perspectives and multiscale responses to the changing oceans, requires a correspondingly diverse body of scholarship in the physical, biological, and social sciences and humanities. This can ensure that a plurality of values and viewpoints is reflected in the research that informs climate policy and may enable the concerns of maritime societies and economic sectors to be heard in key adaptation and mitigation discussions. PMID:26564848

  19. Key ecological responses to nitrogen are altered by climate change

    Science.gov (United States)

    Greaver, T. L.; Clark, C. M.; Compton, J. E.; Vallano, D.; Talhelm, A. F.; Weaver, C. P.; Band, L. E.; Baron, J. S.; Davidson, E. A.; Tague, C. L.; Felker-Quinn, E.; Lynch, J. A.; Herrick, J. D.; Liu, L.; Goodale, C. L.; Novak, K. J.; Haeuber, R. A.

    2016-09-01

    Climate change and anthropogenic nitrogen deposition are both important ecological threats. Evaluating their cumulative effects provides a more holistic view of ecosystem vulnerability to human activities, which would better inform policy decisions aimed to protect the sustainability of ecosystems. Our knowledge of the cumulative effects of these stressors is growing, but we lack an integrated understanding. In this Review, we describe how climate change alters key processes in terrestrial and freshwater ecosystems related to nitrogen cycling and availability, and the response of ecosystems to nitrogen addition in terms of carbon cycling, acidification and biodiversity.

  20. Warming Experiments Underpredict Plant Phenological Responses to Climate Change

    Science.gov (United States)

    Wolkovich, E. M.; Cook, B. I.; Allen, J. M.; Crimmins, T. M.; Betancourt, J. L.; Travers, S. E.; Pau, S.; Regetz, J.; Davies, T. J.; Kraft, N. J. B.; Ault, T. R.; Bolmgren, K.; Mazer, S. J.; McCabe, G. J.; McGill, B. J.; Parmesan, C.; Salamin, N.; Schwartz, M. D.; Cleland, E. E.

    2012-01-01

    Warming experiments are increasingly relied on to estimate plant responses to global climate change. For experiments to provide meaningful predictions of future responses, they should reflect the empirical record of responses to temperature variability and recent warming, including advances in the timing of flowering and leafing. We compared phenology (the timing of recurring life history events) in observational studies and warming experiments spanning four continents and 1,634 plant species using a common measure of temperature sensitivity (change in days per degree Celsius). We show that warming experiments underpredict advances in the timing of flowering and leafing by 8.5-fold and 4.0-fold, respectively, compared with long-term observations. For species that were common to both study types, the experimental results did not match the observational data in sign or magnitude. The observational data also showed that species that flower earliest in the spring have the highest temperature sensitivities, but this trend was not reflected in the experimental data. These significant mismatches seem to be unrelated to the study length or to the degree of manipulated warming in experiments. The discrepancy between experiments and observations, however, could arise from complex interactions among multiple drivers in the observational data, or it could arise from remediable artefacts in the experiments that result in lower irradiance and drier soils, thus dampening the phenological responses to manipulated warming. Our results introduce uncertainty into ecosystem models that are informed solely by experiments and suggest that responses to climate change that are predicted using such models should be re-evaluated.

  1. Warming experiments underpredict plant phenological responses to climate change

    Science.gov (United States)

    Wolkovich, Elizabeth M.; Cook, Benjamin I.; Allen, Jenica M.; Crimmins, Theresa M.; Betancourt, Julio L.; Travers, Steven E.; Pau, Stephanie; Regetz, James; Davies, T. Jonathan; Kraft, Nathan J.B.; Ault, Toby R.; Bolmgren, Kjell; Mazer, Susan J.; McCabe, Gregory J.; McGill, Brian J.; Parmesan, Camille; Salamin, Nicolas; Schwartz, Mark D.; Cleland, Elsa E.

    2012-01-01

    Warming experiments are increasingly relied on to estimate plant responses to global climate change. For experiments to provide meaningful predictions of future responses, they should reflect the empirical record of responses to temperature variability and recent warming, including advances in the timing of flowering and leafing. We compared phenology (the timing of recurring life history events) in observational studies and warming experiments spanning four continents and 1,634 plant species using a common measure of temperature sensitivity (change in days per degree Celsius). We show that warming experiments underpredict advances in the timing of flowering and leafing by 8.5-fold and 4.0-fold, respectively, compared with long-term observations. For species that were common to both study types, the experimental results did not match the observational data in sign or magnitude. The observational data also showed that species that flower earliest in the spring have the highest temperature sensitivities, but this trend was not reflected in the experimental data. These significant mismatches seem to be unrelated to the study length or to the degree of manipulated warming in experiments. The discrepancy between experiments and observations, however, could arise from complex interactions among multiple drivers in the observational data, or it could arise from remediable artefacts in the experiments that result in lower irradiance and drier soils, thus dampening the phenological responses to manipulated warming. Our results introduce uncertainty into ecosystem models that are informed solely by experiments and suggest that responses to climate change that are predicted using such models should be re-evaluated.

  2. Changes in macrophage phenotype as the immune response evolves

    OpenAIRE

    Lichtnekert, Julia; Kawakami, Takahisa; Parks, William C.; Duffield, Jeremy S.

    2013-01-01

    Mononuclear phagocytic cells, including macrophages and dendritic cells, are widely distributed throughout our organs where they perform important homeostatic, surveillance and regenerative tasks. In response to infection or injury, the composition and number of mononuclear phagocytic cells changes remarkably, in part due to the recruitment of inflammatory monocytes from bone marrow. In infection or injury, macrophages and dendritic cells perform important innate and adaptive immune roles fro...

  3. Deciphering transcriptional regulations coordinating the response to environmental changes

    OpenAIRE

    Acuña, Vicente; Aravena, Andrés; Guziolowski, Carito; Eveillard, Damien; Siegel, Anne; Maass, Alejandro

    2016-01-01

    Background Gene co-expression evidenced as a response to environmental changes has shown that transcriptional activity is coordinated, which pinpoints the role of transcriptional regulatory networks (TRNs). Nevertheless, the prediction of TRNs based on the affinity of transcription factors (TFs) with binding sites (BSs) generally produces an over-estimation of the observable TF/BS relations within the network and therefore many of the predicted relations are spurious. Results We present Lomba...

  4. Crop yield response to climate change varies with cropping intensity

    OpenAIRE

    Challinor, AJ; Parkes, B.; Ramirez-Villegas, J.

    2015-01-01

    Projections of the response of crop yield to climate change at different spatial scales are known to vary. However, understanding of the causes of systematic differences across scale is limited. Here, we hypothesize that heterogeneous cropping intensity is one source of scale dependency. Analysis of observed global data and regional crop modelling demonstrate that areas of high vs. low cropping intensity can have systematically different yields, in both observations and simulations. Analysis ...

  5. Policy Responses to Climate Change in Southeast Asia

    OpenAIRE

    Toth, F.L.

    1992-01-01

    This report presents an overview of and summarizes the general conclusions from a UNEP project conducted in Southeast Asia to identify socio-economic impacts of and policy responses to climate change. A series of agricultural crops, river basins, and coastal areas were selected in order to study the biophysical impacts, which were then traced through to the most heavily affected economic activities and social groups. Policy exercises were conducted in Malaysia and Indonesia to present the re...

  6. Explaining simulations through self explaining agents

    NARCIS (Netherlands)

    Harbers, M.; Bosch, K. van den; Meyer, J.J.C.

    2010-01-01

    Several strategies are used to explain emergent interaction patterns in agent-based simulations. A distinction can be made between simulations in which the agents just behave in a reactive way, and simulations involving agents with also pro-active (goal-directed) behavior. Pro-active behavior is mor

  7. Explaining Simulations through Self Explaining Agents

    NARCIS (Netherlands)

    Harbers, M.; Dignum, F.; Bosch, K. van den; Meyer, J.J.C.

    2008-01-01

    Several strategies are used to explain emergent interaction patterns in agent-based simulations. A distinction can be made between simulations in which the agents just behave in a reactive way, and simulations involving agents with also pro-active (goal-directed) behavior. Pro-active behavior is mor

  8. Exploring the universal ecological responses to climate change in a univoltine butterfly.

    Science.gov (United States)

    Fenberg, Phillip B; Self, Angela; Stewart, John R; Wilson, Rebecca J; Brooks, Stephen J

    2016-05-01

    Animals with distinct life stages are often exposed to different temperatures during each stage. Thus, how temperature affects these life stages should be considered for broadly understanding the ecological consequences of climate warming on such species. For example, temperature variation during particular life stages may affect respective change in body size, phenology and geographic range, which have been identified as the "universal" ecological responses to climate change. While each of these responses has been separately documented across a number of species, it is not known whether each response occurs together within a species. The influence of temperature during particular life stages may help explain each of these ecological responses to climate change. Our goal was to determine if monthly temperature variation during particular life stages of a butterfly species can predict respective changes in body size and phenology. We also refer to the literature to assess if temperature variability during the adult stage influences range change over time. Using historical museum collections paired with monthly temperature records, we show that changes in body size and phenology of the univoltine butterfly, Hesperia comma, are partly dependent upon temporal variation in summer temperatures during key stages of their life cycle. June temperatures, which are likely to affect growth rate of the final larval instar, are important for predicting adult body size (for males only; showing a positive relationship with temperature). July temperatures, which are likely to influence the pupal stage, are important for predicting the timing of adult emergence (showing a negative relationship with temperature). Previous studies show that August temperatures, which act on the adult stage, are linked to range change. Our study highlights the importance of considering temperature variation during each life stage over historic time-scales for understanding intraspecific response to

  9. Exploring the universal ecological responses to climate change in a univoltine butterfly.

    Science.gov (United States)

    Fenberg, Phillip B; Self, Angela; Stewart, John R; Wilson, Rebecca J; Brooks, Stephen J

    2016-05-01

    Animals with distinct life stages are often exposed to different temperatures during each stage. Thus, how temperature affects these life stages should be considered for broadly understanding the ecological consequences of climate warming on such species. For example, temperature variation during particular life stages may affect respective change in body size, phenology and geographic range, which have been identified as the "universal" ecological responses to climate change. While each of these responses has been separately documented across a number of species, it is not known whether each response occurs together within a species. The influence of temperature during particular life stages may help explain each of these ecological responses to climate change. Our goal was to determine if monthly temperature variation during particular life stages of a butterfly species can predict respective changes in body size and phenology. We also refer to the literature to assess if temperature variability during the adult stage influences range change over time. Using historical museum collections paired with monthly temperature records, we show that changes in body size and phenology of the univoltine butterfly, Hesperia comma, are partly dependent upon temporal variation in summer temperatures during key stages of their life cycle. June temperatures, which are likely to affect growth rate of the final larval instar, are important for predicting adult body size (for males only; showing a positive relationship with temperature). July temperatures, which are likely to influence the pupal stage, are important for predicting the timing of adult emergence (showing a negative relationship with temperature). Previous studies show that August temperatures, which act on the adult stage, are linked to range change. Our study highlights the importance of considering temperature variation during each life stage over historic time-scales for understanding intraspecific response to

  10. Improving models to predict phenological responses to global change

    Energy Technology Data Exchange (ETDEWEB)

    Richardson, Andrew D. [Harvard College, Cambridge, MA (United States)

    2015-11-25

    The term phenology describes both the seasonal rhythms of plants and animals, and the study of these rhythms. Plant phenological processes, including, for example, when leaves emerge in the spring and change color in the autumn, are highly responsive to variation in weather (e.g. a warm vs. cold spring) as well as longer-term changes in climate (e.g. warming trends and changes in the timing and amount of rainfall). We conducted a study to investigate the phenological response of northern peatland communities to global change. Field work was conducted at the SPRUCE experiment in northern Minnesota, where we installed 10 digital cameras. Imagery from the cameras is being used to track shifts in plant phenology driven by elevated carbon dioxide and elevated temperature in the different SPRUCE experimental treatments. Camera imagery and derived products (“greenness”) is being posted in near-real time on a publicly available web page (http://phenocam.sr.unh.edu/webcam/gallery/). The images will provide a permanent visual record of the progression of the experiment over the next 10 years. Integrated with other measurements collected as part of the SPRUCE program, this study is providing insight into the degree to which phenology may mediate future shifts in carbon uptake and storage by peatland ecosystems. In the future, these data will be used to develop improved models of vegetation phenology, which will be tested against ground observations collected by a local collaborator.

  11. The demographic response to Holocene climate change in the Sahara

    Science.gov (United States)

    Manning, Katie; Timpson, Adrian

    2014-10-01

    The timing and development of Holocene human occupation in the now hyperarid Sahara has major implications for understanding links between climate change, demography and cultural adaptation. Here we use summed probability distributions from 3287 calibrated 14C dates from 1011 archaeological sites to demonstrate a major and rapid demographic shift between 10,500 and 5500 years BP. This event corresponds with the African Humid Period (AHP) and is sub-continental in scale, indicating climate as the prime factor driving broad-scale population dynamics in northern Africa. Furthermore, by providing a high temporal resolution proxy for effective carrying capacity our population curve offers an independent estimate of environmental change in northern Africa, indicating a temporal delay in the terrestrial response to atmospheric climate change. These results highlight the degree to which human demography is a function of environment at the appropriate scale of observation in both time and space and sheds important new light on the social response to global environmental change.

  12. Strain-specific responses of Emiliania huxleyi to changing seawater carbonate chemistry

    Directory of Open Access Journals (Sweden)

    P. Ziveri

    2009-04-01

    Full Text Available Four strains of the coccolithophore Emiliania huxleyi (RCC1212, RCC1216, RCC1238, RCC1256 were grown in dilute batch culture at four CO2 levels ranging from ~200 μatm to ~1200 μatm. Growth rate, particulate organic carbon content, and particulate inorganic carbon content were measured, and organic and inorganic carbon production calculated. The four strains did not show a uniform response to carbonate chemistry changes in any of the analysed parameters and none of the four strains displayed a response pattern previously described for this species. We conclude that the sensitivity of different strains of E. huxleyi to acidification differs substantially and that this likely has a genetic basis. We propose that this can explain apparently contradictory results reported in the literature.

  13. Hydrological Responses to Land-Use Change Scenarios under Constant and Changed Climatic Conditions.

    Science.gov (United States)

    Zhang, Ling; Nan, Zhuotong; Yu, Wenjun; Ge, Yingchun

    2016-02-01

    This study quantified the hydrological responses to land-use change scenarios in the upper and middle Heihe River basin (HRB), northwest China, under constant and changed climatic conditions by combining a land-use/cover change model (dynamic conversion of land use and its effects, Dyna-CLUE) and a hydrological model (soil and water assessment tool, SWAT). Five land-use change scenarios, i.e., historical trend (HT), ecological protection (EP), strict ecological protection (SEP), economic development (ED), and rapid economic development (RED) scenarios, were established. Under constant climatic condition, hydrological variations are only induced by land-use changes in different scenarios. The changes in mean streamflow at the outlets of the upper and the middle HRB are not pronounced, although the different scenarios produce different outcomes. However, more pronounced changes are observed on a subbasin level. The frequency of extreme flood is projected to decrease under the SEP scenario, while under the other scenarios, no changes can be found. Two emission scenarios (A1B and B1) of three general circulation models (HadCM3, CGCM3, and CCSM3) were employed to generate future possible climatic conditions. Under changed climatic condition, hydrological variations are induced by the combination of land-use and climatic changes. The results indicate that the impacts of land-use changes become secondary when the changed climatic conditions have been considered. The frequencies of extreme flood and drought are projected to decrease and increase, respectively, under all climate scenarios. Although some agreements can be reached, pronounced difference of hydrological responses can be observed for different climate scenarios of different GCMs.

  14. Hydrological Responses to Land-Use Change Scenarios under Constant and Changed Climatic Conditions

    Science.gov (United States)

    Zhang, Ling; Nan, Zhuotong; Yu, Wenjun; Ge, Yingchun

    2016-02-01

    This study quantified the hydrological responses to land-use change scenarios in the upper and middle Heihe River basin (HRB), northwest China, under constant and changed climatic conditions by combining a land-use/cover change model (dynamic conversion of land use and its effects, Dyna-CLUE) and a hydrological model (soil and water assessment tool, SWAT). Five land-use change scenarios, i.e., historical trend (HT), ecological protection (EP), strict ecological protection (SEP), economic development (ED), and rapid economic development (RED) scenarios, were established. Under constant climatic condition, hydrological variations are only induced by land-use changes in different scenarios. The changes in mean streamflow at the outlets of the upper and the middle HRB are not pronounced, although the different scenarios produce different outcomes. However, more pronounced changes are observed on a subbasin level. The frequency of extreme flood is projected to decrease under the SEP scenario, while under the other scenarios, no changes can be found. Two emission scenarios (A1B and B1) of three general circulation models (HadCM3, CGCM3, and CCSM3) were employed to generate future possible climatic conditions. Under changed climatic condition, hydrological variations are induced by the combination of land-use and climatic changes. The results indicate that the impacts of land-use changes become secondary when the changed climatic conditions have been considered. The frequencies of extreme flood and drought are projected to decrease and increase, respectively, under all climate scenarios. Although some agreements can be reached, pronounced difference of hydrological responses can be observed for different climate scenarios of different GCMs.

  15. Changes in muscle spindle firing in response to length changes of neighboring muscles.

    Science.gov (United States)

    Smilde, Hiltsje A; Vincent, Jake A; Baan, Guus C; Nardelli, Paul; Lodder, Johannes C; Mansvelder, Huibert D; Cope, Tim C; Maas, Huub

    2016-06-01

    Skeletal muscle force can be transmitted to the skeleton, not only via its tendons of origin and insertion but also through connective tissues linking the muscle belly to surrounding structures. Through such epimuscular myofascial connections, length changes of a muscle may cause length changes within an adjacent muscle and hence, affect muscle spindles. The aim of the present study was to investigate the effects of epimuscular myofascial forces on feedback from muscle spindles in triceps surae muscles of the rat. We hypothesized that within an intact muscle compartment, muscle spindles not only signal length changes of the muscle in which they are located but can also sense length changes that occur as a result of changing the length of synergistic muscles. Action potentials from single afferents were measured intra-axonally in response to ramp-hold release (RHR) stretches of an agonistic muscle at different lengths of its synergist, as well as in response to synergist RHRs. A decrease in force threshold was found for both soleus (SO) and lateral gastrocnemius afferents, along with an increase in length threshold for SO afferents. In addition, muscle spindle firing could be evoked by RHRs of the synergistic muscle. We conclude that muscle spindles not only signal length changes of the muscle in which they are located but also local length changes that occur as a result of changing the length and relative position of synergistic muscles.

  16. Response of Mycorrhizal Diversity to Current Climatic Changes

    Directory of Open Access Journals (Sweden)

    Stephen E. Williams

    2011-01-01

    Full Text Available Form and function of mycorrhizas as well as tracing the presence of the mycorrhizal fungi through the geological time scale are herein first addressed. Then mycorrhizas and plant fitness, succession, mycorrhizas and ecosystem function, and mycorrhizal resiliency are introduced. From this, four hypotheses are drawn: (1 mycorrhizal diversity evolved in response to changes in Global Climate Change (GCC environmental drivers, (2 mycorrhizal diversity will be modified by present changes in GCC environmental drivers, (3 mycorrhizal changes in response to ecological drivers of GCC will in turn modify plant, community, and ecosystem responses to the same, and (4 Mycorrhizas will continue to evolve in response to present and future changes in GCC factors. The drivers of climate change examined here are: CO2 enrichment, temperature rise, altered precipitation, increased N-deposition, habitat fragmentation, and biotic invasion increase. These impact the soil-rhizosphere, plant and fungal physiology and/or ecosystem(s directly and indirectly. Direct effects include changes in resource availability and change in distribution of mycorrhizas. Indirect effects include changes in below ground allocation of C to roots and changes in plant species distribution. GCC ecological drivers have been partitioned into four putative time frames: (1 Immediate (1–2 years impacts, associated with ecosystem fragmentation and habitat loss realized through loss of plant-hosts and disturbance of the soil; (2 Short-term (3–10 year impacts, resultant of biotic invasions of exotic mycorrhizal fungi, plants and pests, diseases and other abiotic perturbations; (3 Intermediate-term (11–20 year impacts, of cumulative and additive effects of increased N (and S deposition, soil acidification and other pollutants; and (4 Long-term (21–50+ year impacts, where increased temperatures and CO2 will destabilize global rainfall patterns, soil properties and plant ecosystem resilience. Due

  17. School Social Workers as Response to Intervention Change Champions

    Directory of Open Access Journals (Sweden)

    Deneca Winfrey Avant

    2016-02-01

    Full Text Available School social workers (SSWs are known for serving students with social, emotional, and academic needs. Implementing Response to Intervention (RTI/Multi-Tiered System of Supports (MTSS is one avenue in which SSWs play an integral role by guiding the development and implementation of student interventions. RTI/MTSS requires substantive and multifaceted system changes that involve more than simply adopting new approaches. This paradigm shift brings change which may not be desired or easily accepted by school systems. However, developing collaborative relationships and using effective leadership strategies throughout the RTI/MTSS transformation can be a pathway to success. A survey of 192 SSWs in Illinois revealed the challenges that SSWs experienced as the process of implementing RTI/MTSS transformed them into change leaders. This revelation was viewed as an opportunity to closely align social and emotional practices with students’ academic achievement.

  18. Predicting the Response of Electricity Load to Climate Change

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, Patrick [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Colman, Jesse [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kalendra, Eric [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2015-07-28

    Our purpose is to develop a methodology to quantify the impact of climate change on electric loads in the United States. We perform simple linear regression, assisted by geospatial smoothing, on paired temperature and load time-series to estimate the heating- and coolinginduced sensitivity to temperature across 300 transmission zones and 16 seasonal and diurnal time periods. The estimated load sensitivities can be coupled with climate scenarios to quantify the potential impact of climate change on load, with a primary application being long-term electricity scenarios. The method allows regional and seasonal differences in climate and load response to be reflected in the electricity scenarios. While the immediate product of this analysis was designed to mesh with the spatial and temporal resolution of a specific electricity model to enable climate change scenarios and analysis with that model, we also propose that the process could be applied for other models and purposes.

  19. RESPONSIBILITY TO PROTECT. QUALITATIVE CHANGE IN UNDERSTANDING SOVEREIGNTY?

    Directory of Open Access Journals (Sweden)

    Tomasz Lewandowski

    2014-08-01

    Full Text Available Purpose – This article analyzes and evaluates a conceptual switch in contemporary understanding of sovereignty under constitutional and international law. It mainly focuses on sovereignty as responsibility as provided by the concept of responsibility to protect. Design/methodology/approach – Article answers this question in three parts. Firstly, it elaborates on traditional understanding of sovereignty as a state oriented concept. Secondly, it discusses the concept of responsibility to protect and how it challenges a state centered sovereignty. It concludes with assessing sovereignty as responsibility and consequences of such approach. Findings – Sovereignty as responsibility has a dual character. Firstly, it is the government's responsibility for the well being of people it represents. Secondly, it is the responsibility of international community to protect populations from mass atrocities based on the idea of subsidiarity and international solidarity. While underlining the normative character of the former the article questions (at least now its existence in case of the latter. Article leads to conclusion that sovereignty continues to evolve as the foundation for the entire international system and that protection of human rights only reinforces its quality and value. Research limitations/implications – The main research limitation is a dubious character of responsibility to protect. Due to the controversial state practice it is difficult to assess its current normative character. This limits the research on the qualitative change of sovereignty and its impact on international relations. Practical implications – Article underlines that any action taken by members of international community while protecting endangered population must follow international and constitutional norms. This would clarify the state practice and opinio iuris which are the conditions to establish the customary character of responsibility to protect

  20. All or none cell responses of Ca2+-dependent K channels elicited by calcium or lead in human red cells can be explained by heterogeneity of agonist distribution

    International Nuclear Information System (INIS)

    We have studied the all or none cell response of Ca2+-dependent K+ channels to added Ca in human red cells depleted of ATP by incubation with iodoacetate and inosine. A procedure was used which allows separation and differential analysis of responding and nonresponding cells. Responding (H for heavy) cells incubated in medium containing 5 mM K lose KCl and water and increase their density to the point of sinking on diethylphthalate (specific gravity = 1.12) on centrifugation. Nonresponding (L for light) cells do not lose KCl at all. There is no intermediate behavior. Increasing the Ca concentration in the medium increases the fraction of cells which become H. No differences in the sensitivity to Ca2+ of the individual K+ channels were detected in inside-out vesicles prepared either from H or from L cells. The Ca content of H cells was higher than that of L cells. Cells depleted of ATP by incubation with iodoacetate and inosine sustain pump-leak Ca fluxes of about 15 mumol/liter cells per hour. ATP seems to be resynthesized in these cells at the expense of cell 2,3-diphosphoglycerate stores at a rate of about 150 mumol/liter cells per hour. Inhibition of 2,3-diphosphoglycerate phosphatase by tetrathionate increased 6-8 times the measured rate of uptake of external 45Ca. This was accompanied by an increase in the fraction of H cells. All or none cell responses of Ca2+-dependent K channels have also been evidenced in intact human red cells on addition of Pb. They have the same characteristics as those in responding and nonresponding cells. The detailed study of the kinetics of Pb-induced shrinkage of red cells suspended in medium containing 5 mM K showed that changes of Pb concentration changed not only the fraction of H cells but also the rate of shrinkage of responding cells. H cells generated by Pb treatment contained significantly more lead than L cells

  1. The More Things Change, the More They Stay the Same? Prior Achievement Fails to Explain Gender Inequality in Entry into Stem College Majors over Time

    Science.gov (United States)

    Riegle-Crumb, Catherine; King, Barbara; Grodsky, Eric; Muller, Chandra

    2012-01-01

    This article investigates the empirical basis for often-repeated arguments that gender differences in entrance into science, technology, engineering, and mathematics (STEM) majors are largely explained by disparities in prior achievement. Analyses use data from three national cohorts of college matriculates across three decades to consider…

  2. Longitudinal Changes in Depressive Circuitry in Response to Neuromodulation Therapy

    Science.gov (United States)

    Pathak, Yagna; Salami, Oludamilola; Baillet, Sylvain; Li, Zhimin; Butson, Christopher R.

    2016-01-01

    Background: Major depressive disorder (MDD) is a public health problem worldwide. There is increasing interest in using non-invasive therapies such as repetitive transcranial magnetic stimulation (rTMS) to treat MDD. However, the changes induced by rTMS on neural circuits remain poorly characterized. The present study aims to test whether the brain regions previously targeted by deep brain stimulation (DBS) in the treatment of MDD respond to rTMS, and whether functional connectivity (FC) measures can predict clinical response. Methods: rTMS (20 sessions) was administered to five MDD patients at the left-dorsolateral prefrontal cortex (L-DLPFC) over 4 weeks. Magnetoencephalography (MEG) recordings and Montgomery-Asberg depression rating scale (MADRS) assessments were acquired before, during and after treatment. Our primary measures, obtained with MEG source imaging, were changes in power spectral density (PSD) and changes in FC as measured using coherence. Results: Of the five patients, four met the clinical response criterion (40% or greater decrease in MADRS) after 4 weeks of treatment. An increase in gamma power at the L-DLPFC was correlated with improvement in symptoms. We also found that increases in delta band connectivity between L-DLPFC/amygdala and L-DLPFC/pregenual anterior cingulate cortex (pACC), and decreases in gamma band connectivity between L-DLPFC/subgenual anterior cingulate cortex (sACC), were correlated with improvements in depressive symptoms. Conclusions: Our results suggest that non-invasive intervention techniques, such as rTMS, modulate the ongoing activity of depressive circuits targeted for DBS, and that MEG can capture these changes. Gamma oscillations may originate from GABA-mediated inhibition, which increases synchronization of large neuronal populations, possibly leading to increased long-range FC. We postulate that responses to rTMS could provide valuable insights into early evaluation of patient candidates for DBS surgery. PMID

  3. Responses of northern forest plants to atmospheric changes

    Energy Technology Data Exchange (ETDEWEB)

    Laine, K.; Huttunen, S.; Kauppi, M.; Ohtonen, R.; Laehdesmaeki, P. [Oulu Univ. (Finland). Dept. of Biology

    1996-12-31

    This research programme has been under way since 1990 to study the long-term synergistic effects of air pollutants and changing climatic conditions on the northern forest ecosystem and to increase the knowledge of climatic change and its consequences for the fragile northern nature. Ecological, physiological, morphological and biochemical methods have been used to study the responses of forest trees, dwarf shrubs, lichens and soil biology to environmental changes. The research programme is divided into four subprojects concentrating on different ecosystem levels. The subprojects are: (1) life, growth and survival strategies of northern dwarf shrubs under the pressure of a changing environment, (2) forest trees under the impact of air pollutants, increasing CO{sub 2} and UV-B, (3) susceptibility of lichens to air pollution and climatic change and (4) impact of elevated atmospheric CO{sub 2} and O{sub 3} on soil biology with special reference to carbon allocation and N fixation in symbiotic systems. This report summarizes the results of short-term experiments which showed many ecological and physiological changes in almost all elements of the northern boreal forests. These species-level measurements focused on the key species of the northern boreal forest, which have been thought to be useful in large-scale ecosystem experiments and modelling. The results will also facilitate the further studies on the patterns of plant species distribution and northern ecosystem function with respect to the environmental parameters that are expected to change along with global change (e.g. temperature, airchemistry, UV-B, snow condition)

  4. Changes in spatiotemporal patterns of hydrological response after partial deforestation

    Science.gov (United States)

    Wiekenkamp, Inge; Huisman, Johan Alexander; Reemt Bogena, Heye; Lin, Henry; Drüe, Clemens; Vereecken, Harry

    2016-04-01

    Predicting the effects of land use change on hydrology can be extremely challenging. It requires looking beyond the current structure and functioning of hydrological systems to predict how the system is influenced in a changed setting. Although the hydrological effects of land use change have been studied extensively, only few high resolution datasets are available to accurately describe, model and predict detailed changes in spatiotemporal patterns of hydrological fluxes and states due to land use change. The TERENO test site Wüstebach provides a unique monitoring setup to measure the major components of the water balance (evapotranspiration, discharge, precipitation) and the spatiotemporal distribution of soil moisture before and after a partial deforestation. Here, we present 5 years of measured hydrological data, including soil moisture and water budget component data 3 years before and 2 years after the partial deforestation. A data-driven investigation was used to understand changes and related feedback mechanisms in spatiotemporal hydrological response patterns. The effects of deforestation on soil moisture and evapotranspiration were analyzed by comparing states and fluxes for the control and the deforested area. The effects on discharge characteristics were analyzed using discharge metrics, including baseflow separation, peakflow rates and time to peak. Changes in preferential flow occurrence were identified using a sensor response time analysis of soil moisture measurements before and after the deforestation where preferential flow was identified as a non-sequential sequence of sensor response times within the soil. As expected from earlier studies, the partial deforestation caused a decrease in evapotranspiration and an increase in discharge. A closer look at the high resolution datasets however reveals new insights in the intra-annual variability of the water balance components. The overall decrease in evapotranspiration caused a large increase in soil

  5. Using Item Response Theory to Assess Changes in Student Performance Based on Changes in Question Wording

    Science.gov (United States)

    Schurmeier, Kimberly D.; Atwood, Charles H.; Shepler, Carrie G.; Lautenschlager, Gary J.

    2010-01-01

    Five years of longitudinal data for general chemistry student assessments at the University of Georgia have been analyzed using item response theory (IRT). Our analysis indicates that minor changes in question wording on exams can make significant differences in student performance on assessment questions. This analysis encompasses data from over…

  6. Trends and responses to global change of China's arid regions

    Institute of Scientific and Technical Information of China (English)

    Weixi YANG

    2009-01-01

    Ⅰ analyzed and elaborated the trends in and responses to global change in arid regions of China, from the perspective of nine variables, i.e., temperature, precipitation, river runoff, melting glaciers, water level of lakes, wind power and evaporation, vegetation, oases, and desertification. The climate and hydrology data Ⅰ citedrepresent many years of observations. Ⅰ conclude that, since the 1980s, the climate in arid regions of China has clearly changed with rising temperatures and precipitation in most areas. Wind power and the number of galestorm days have continuously decreased, which resulted in an improvement of humid conditions and increases in river discharge and water levels of lakes. Simultaneously, vegetation also has improved and the process of deserti-fication has essentially been arrested. Although there are some unfavorable developments, such as decreased river flows or flow interruptions and downstream oases have suffered from degradation, these incidental cases should not distract our attention from the generally favorable trends during the middle and late 20th century. These discordant phenomena are not consequences of climate change but rather of unsuitable human activities. Despitea substantial increase in precipitation, the level of the original precipitation was so small that any increase in precipitation was still small. As a result, none of the fundamental conditions such as a scarcity of water resources and precipitation nor the landscape of drought-ridden deserts in the arid regions will change. The vulnerability of the eco-environmental system in the arid regions will not change fundamentally either in the near future.

  7. Farmer's response to changing climate in North East India

    Science.gov (United States)

    De, Utpal Kumar

    2015-02-01

    Diversification of land use in the cultivation of various crops provides an alternative way to moderate the climate risk. By choosing alternative crops that are resilient to various weather parameters, farmers can reduce the crop damage and achieve optimum output from their limited land resources. Apart from other adaptation measures, crop diversity can reflect farmers' response towards changing climate uncertainty. This paper tries to examine the changing climatic condition through spatio-temporal variation of two important weather variables (precipitation and temperature) in the largest North-East Indian state, Assam, since 1950. It is examined by the variation in crop diversification index. We have used (1) Herfindahl Index for measuring degree of diversification and (2) locational quotient for measuring the changes in the regional crop concentration. The results show that, in almost all the districts, crop specialization has been taking place slowly and that happened mostly in the last phase of our study. The hilly and backward districts recorded more diversification but towards lower value crops. It goes against the normal feature of crop diversification where farmers diversify in favour of high value crops. Employing ordinary least squares method and/or Fixed Effect model, irrigation is found to have significant impact on crop diversification; while the flood plain zones and hill zones are found to have better progress in this regard, which has been due to the survival necessity of poor farmers living the zone. Thus crop diversity does not reflect very significant response from the farmers' side towards changing weather factors (except rainfall) though they have significant impact on the productivity of various crops, and thus profitability. The study thus suggests the necessity for rapid and suitable diversification as alternative climate change mitigation in the long run.

  8. Global precipitation response to changing external forcings since 1870

    Directory of Open Access Journals (Sweden)

    A. Bichet

    2011-03-01

    Full Text Available Predicting and adapting to changes in the hydrological cycle is one of the major challenges for the twenty-first century. To better estimate how it will respond to future changes in climate forcings, it is crucial to understand how it has evolved in the past and why. In our study, we use an atmospheric global climate model with prescribed sea surface temperatures (SSTs to investigate how changing external climate forcings have affected global land temperature and precipitation in the period 1870–2005. We show that prescribed SSTs (encapsulating other forcings are the dominant forcing driving the decadal variability of land temperature and precipitation since 1870. On top of this SSTs forcing, we also find that the atmosphere-only response to increasing aerosol emissions is a reduction in global land temperature and precipitation by up to 0.4 °C and 30 mm year−1, respectively, between about 1930 and 2000. Similarly, the atmosphere-only response to increasing greenhouse gas concentrations is an increase in global land temperature and precipitation by up to 0.25 °C and 10 mm year−1, respectively, between about 1950 and 2000. Finally, our results also suggest that between about 1950 and 1970, increasing aerosol emissions had a larger impact on the hydrological cycle than increasing greenhouse gases concentrations.

  9. Soil Microbial Community Responses to Long-Term Global Change Factors in a California Grassland

    Science.gov (United States)

    Qin, K.; Peay, K.

    2015-12-01

    Soil fungal and bacterial communities act as mediators of terrestrial carbon and nutrient cycling, and interact with the aboveground plant community as both pathogens and mutualists. However, these soil microbial communities are sensitive to changes in their environment. A better understanding of the response of soil microbial communities to global change may help to predict future soil microbial diversity, and assist in creating more comprehensive models of terrestrial carbon and nutrient cycles. This study examines the effects of four global change factors (increased temperature, increased variability in precipitation, nitrogen deposition, and CO2 enrichment) on soil microbial communities at the Jasper Ridge Global Change Experiment (JRGCE), a full-factorial global change manipulative experiment on three hectares of California grassland. While similar studies have examined the effects of global change on soil microbial communities, few have manipulated more factors or been longer in duration than the JRGCE, which began field treatments in 1998. We find that nitrogen deposition, CO2 enrichment, and increased variability in precipitation significantly affect the structure of both fungal and bacterial communities, and explain more of the variation in the community structures than do local soil chemistry or aboveground plant community. Fungal richness is correlated positively with soil nitrogen content and negatively with soil water content. Arbuscular mycorrhizal fungi (AMF), which associate closely with herbaceous plants' roots and assist in nutrient uptake, decrease in both richness and relative abundance in elevated CO2 treatments.

  10. Slow Wetland Response to Hydrological Change: Press Response or Regime Shift?

    Science.gov (United States)

    Gell, P.; Kattel, G.

    2015-12-01

    Lakes vary in response to minor disturbances and, where stabilising feedbacks exist, tend to return to a particular stable state. If the disturbance is strong enough the stabilising forces may be overcome and the lake passes a threshold whereby it shifts into a new state controlled by a new suite of negative feedbacks. A typical switch in state is thought to occur in shallow lake systems whereby a pulse of sediment or nutrients may drive an increase in phytoplankton impacting the light regime. This impacts negatively on submerged plants which results in greater entrainment of benthic sediments and release of buried nutrients. These strengthen the competitive advantage of phytoplankton and entrench the lake in a new state. Multiple diatom-based sedimentary records of change in wetlands in the lower River Murray, Australia, have revealed assemblage turnover following river regulation and the impoundment of the estuary. Typically, benthic and epiphytic flora have yielded to planktonic and disturbance taxa indicative the loss of aquatic plants and a decline in the light regime consistent with regime shift theory. This evidence is supported by changes in the remains of macrophytes, cladocerans and stable isotopes which reveal the loss of plants and the shift to a pelagic system. However, rather than exhibiting flickering before changing abruptly, these systems have changed gradually over several decades. It could be argued that this represents a slow response to a threshold change. Alternatively, it is merely an ongoing response to the persistent pressure exerted by increased fluxes of sediments and nutrients.

  11. Changes in macrophage phenotype as the immune response evolves

    Science.gov (United States)

    Lichtnekert, Julia; Kawakami, Takahisa; Parks, William C.; Duffield, Jeremy S.

    2013-01-01

    Mononuclear phagocytic cells, including macrophages and dendritic cells, are widely distributed throughout our organs where they perform important homeostatic, surveillance and regenerative tasks. In response to infection or injury, the composition and number of mononuclear phagocytic cells changes remarkably, in part due to the recruitment of inflammatory monocytes from bone marrow. In infection or injury, macrophages and dendritic cells perform important innate and adaptive immune roles from the initial insult through repair and regeneration of the tissue and resolution of inflammation. Evidence from mouse models of disease has shown increasing complexity and subtlety to the mononuclear phagocytic system, which will be reviewed here. New studies show that in addition to monocytes, the resident populations of mononuclear phagocytes expand in disease states and play distinct but important roles in the immune response. Finally, new insights into these functionally diverse cells are now translating into therapeutics to treat human disease. PMID:23747023

  12. Rotor response for transient unbalance changes in a nonlinear simulation

    Science.gov (United States)

    Hine, M. J.; Landis, C. E.; Beatty, R. F.

    1985-01-01

    Transient unbalance shifts were determined not to excite a rotor instability in the high pressure turbomachinery of the Space Shuttle Main Engine using the current rotor dynamic models. Sudden unbalance changes of relatively small magnitudes during fast-speed ramps showed stable nonsynchronous motion depending on the resultant unbalance distribution at subsequent high speed dwells. Transient moment unbalance may initiate a limit cycle subsynchronous response that shortly decays, but a persistent subsynchronous with large amplitudes was never achieved. These limit cycle subsynchronous amplitudes appear to be minimized with lower unbalance magnitudes, which indicates improved rotor balancing would sustain synchronous motion only. The transient unbalance phenomenon was determined to be an explanation for synchronous response shifts often observed during engine tests.

  13. Climate Change and the Concept of Shared Responsibility

    DEFF Research Database (Denmark)

    Martinsen, Franziska; Seibt, Johanna

    2013-01-01

    the spatial to the temporal dimension of such wide-scope results of individual actions. This shift from ‘global ethics’ to ‘intergenerational ethics’ and, in particular, ‘climate ethics’ requires some new analytical concepts, however. In this paper we provide a definition of wide-scope responsibility geared...... to articulate our moral concerns about emergent effects in complex systems, such as climate change. Working from Iris Marion Young’s “social connection model of responsibility”, we present a notion of shared ecological responsibility with global and intergenerational scope. We show that our account...... is not affected by the so-called non-identity objection to intergenerational ethics. Since we work from an action-theoretic rather than normative perspective, our account is ‘ethically parametrized’ in the sense that it can be combined with different conceptions of structural and intergenerational justice...

  14. Responses of vegetation growth to climate change in china

    Science.gov (United States)

    Li, Z.; Zhou, T.

    2015-04-01

    Global warming-related climate changes have significantly impacted the growth of terrestrial vegetation. Quantifying the spatiotemporal characteristic of the vegetation's response to climate is crucial for assessing the potential impacts of climate change on vegetation. In this study, we employed the normalized difference vegetation index (NDVI) and the standardized precipitation evapotranspiration index (SPEI) that was calculated for various time scales (1 to 12 months) from monthly records of mean temperature and precipitation totals using 511 meteorological stations in China to study the response of vegetation types to droughts. We separated the NDVI into 12 time series (one per month) and also used the SPEI of 12 droughts time scales to make the correlation. The results showed that the differences exist in various vegetation types. For needle-leaved forest, broadleaf forest and shrubland, they responded to droughts at long time scales (9 to 12 months). For grassland, meadow and cultivated vegetation, they responded to droughts at short time scales (1 to 5months). The positive correlations were mostly found in arid and sub-arid environments where soil water was a primary constraining factor for plant growth, and the negative correlations always existed in humid environments where temperature and radiation played significant roles in vegetation growth. Further spatial analysis indicated that the positive correlations were primarily found in northern China, especially in northwestern China, which is a region that always has water deficit, and the negative correlations were found in southern China, especially in southeastern China, that is a region has water surplus most of the year. The disclosed patterns of spatiotemporal responses to droughts are important for studying the impact of climate change to vegetation growth.

  15. Genomic counter-stress changes induced by the relaxation response.

    Directory of Open Access Journals (Sweden)

    Jeffery A Dusek

    Full Text Available BACKGROUND: Mind-body practices that elicit the relaxation response (RR have been used worldwide for millennia to prevent and treat disease. The RR is characterized by decreased oxygen consumption, increased exhaled nitric oxide, and reduced psychological distress. It is believed to be the counterpart of the stress response that exhibits a distinct pattern of physiology and transcriptional profile. We hypothesized that RR elicitation results in characteristic gene expression changes that can be used to measure physiological responses elicited by the RR in an unbiased fashion. METHODS/PRINCIPAL FINDINGS: We assessed whole blood transcriptional profiles in 19 healthy, long-term practitioners of daily RR practice (group M, 19 healthy controls (group N(1, and 20 N(1 individuals who completed 8 weeks of RR training (group N(2. 2209 genes were differentially expressed in group M relative to group N(1 (p<0.05 and 1561 genes in group N(2 compared to group N(1 (p<0.05. Importantly, 433 (p<10(-10 of 2209 and 1561 differentially expressed genes were shared among long-term (M and short-term practitioners (N(2. Gene ontology and gene set enrichment analyses revealed significant alterations in cellular metabolism, oxidative phosphorylation, generation of reactive oxygen species and response to oxidative stress in long-term and short-term practitioners of daily RR practice that may counteract cellular damage related to chronic psychological stress. A significant number of genes and pathways were confirmed in an independent validation set containing 5 N(1 controls, 5 N(2 short-term and 6 M long-term practitioners. CONCLUSIONS/SIGNIFICANCE: This study provides the first compelling evidence that the RR elicits specific gene expression changes in short-term and long-term practitioners. Our results suggest consistent and constitutive changes in gene expression resulting from RR may relate to long term physiological effects. Our study may stimulate new

  16. A Novel Tropical Dry Forests: A Response to Environmental Change.

    Science.gov (United States)

    Lugo, A. E.; Molina, S.

    2015-12-01

    Dry Forest environments are favorable to human settlement and activities, leading to deforestation, agricultural enterprises, land degradation, and abandonment. As a result, tropical dry forests are vulnerable and experience a high rate of cover loss, which often requires restoration activities. We have studied the natural regeneration of dry forests in Puerto Rico following a variety of human activities including farming, cattle pasturing, charcoal production, and human dwellings. Our results show a high level of forest resilience to anthropogenic disturbances but also a change of species composition relative to undisturbed native forests. This novelty of forest composition represents a natural response to environmental changes induced by human activity and pre-adapts forests to conditions in the Anthropocene.

  17. Climate Change Responsibility and China's Endeavor

    Institute of Scientific and Technical Information of China (English)

    Xu Huaqing; Yu Shengmin

    2011-01-01

    The problem of climate change is a global challenge. It is closely associated with social development and human survival, and it has a significant impact to all countries on energy develop- ment, economic competitiveness, technological innovation, and way of life. In recent years, with the rapid economic development in China, there is a rumor that the rapid growth of China's carbon dioxide emission offset the efforts of the international community in reducing emissions, and China should bear the international responsibility corresponding to its significant role in greenhouse gas emission, which obviously are unfair and not objective. As this paper reveals, "China environment responsibility" that is the socalled "China environment threat" or theories, China has made a positive contribution to addressing the climate change in the past and China will still be the backbone on the protection of global climate in the future.

  18. Investigation of rice proteomic change in response to microgravity

    Science.gov (United States)

    Sun, Weining

    Gravity is one of the environmental factors that control development and growth of plants. Plant cells which are not part of specialized tissues such as the root columella can also sense gravity. Space environment, such as space shuttle missions, space labortories and space stations, etc. provide unique oppotunities to study the microgravity response of plant. During the Shenzhou 8 mission in November 2011, we cultured rice cali on the spaceship and the samples were fixed 4 days after launch. The flying samples in the static position (micro g, mug) and in the centrifuge which provide 1 g force to mimic the 1 g gravity in space, were recovered and the proteome changes were analyzed by iTRAQ. In total, 4840 proteins were identified, including 2085 proteins with function annotation by GO analysis. 431 proteins were changed >1.5 fold in space µg /ground group, including 179 up-regulated proteins and down-regulated 252 proteins. 321 proteins were changed >1.5 fold in space muµg / space 1 g group, among which 205 proteins were the same differentially expressed proteins responsive to microgravity. Enrichment of the differnetially expressed proteins by GO analysis showed that the ARF GTPase activity regulation proteins were enriched when compared the space µg with space 1 g sample, whereas the nucleic acid binding and DNA damage repairing proteins were enriched when compared the space µg and ground sample. Microscopic comparison of the rice cali showed that the space grown cells are more uniformed in size and proliferation, suggesting that cell proliferation pattern was changed in space microgravity conditions.

  19. Terrestrial ecosystem responses to global change: A research strategy

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-09-01

    Uncertainty about the magnitude of global change effects on terrestrial ecosystems and consequent feedbacks to the atmosphere impedes sound policy planning at regional, national, and global scales. A strategy to reduce these uncertainties must include a substantial increase in funding for large-scale ecosystem experiments and a careful prioritization of research efforts. Prioritization criteria should be based on the magnitude of potential changes in environmental properties of concern to society, including productivity; biodiversity; the storage and cycling of carbon, water, and nutrients; and sensitivity of specific ecosystems to environmental change. A research strategy is proposed that builds on existing knowledge of ecosystem responses to global change by (1) expanding the spatial and temporal scale of experimental ecosystem manipulations to include processes known to occur at large scales and over long time periods; (2) quantifying poorly understood linkages among processes through the use of experiments that manipulate multiple interacting environmental factors over a broader range of relevant conditions than did past experiments; and (3) prioritizing ecosystems for major experimental manipulations on the basis of potential positive and negative impacts on ecosystem properties and processes of intrinsic and/or utilitarian value to humans and on feedbacks of terrestrial ecosystems to the atmosphere.

  20. Financial market response to extreme events indicating climatic change

    Science.gov (United States)

    Anttila-Hughes, J. K.

    2016-05-01

    A variety of recent extreme climatic events are considered to be strong evidence that the climate is warming, but these incremental advances in certainty often seem ignored by non-scientists. I identify two unusual types of events that are considered to be evidence of climate change, announcements by NASA that the global annual average temperature has set a new record, and the sudden collapse of major polar ice shelves, and then conduct an event study to test whether news of these events changes investors' valuation of energy companies, a subset of firms whose future performance is closely tied to climate change. I find evidence that both classes of events have influenced energy stock prices since the 1990s, with record temperature announcements on average associated with negative returns and ice shelf collapses associated with positive returns. I identify a variety of plausible mechanisms that may be driving these differential responses, discuss implications for energy markets' views on long-term regulatory risk, and conclude that investors not only pay attention to scientifically significant climate events, but discriminate between signals carrying different information about the nature of climatic change.

  1. Interpreting physiological responses to environmental change through gene expression profiling.

    Science.gov (United States)

    Gracey, Andrew Y

    2007-05-01

    Identification of differentially expressed genes in response to environmental change offers insights into the roles of the transcriptome in the regulation of physiological responses. A variety of methods are now available to implement large-scale gene expression screens, and each method has specific advantages and disadvantages. Construction of custom cDNA microarrays remains the most popular route to implement expression screens in the non-model organisms favored by comparative physiologists, and we highlight some factors that should be considered when embarking along this path. Using a carp cDNA microarray, we have undertaken a broad, system-wide gene expression screen to investigate the physiological mechanisms underlying cold and hypoxia acclimation. This dataset provides a starting point from which to explore a range of specific mechanistic hypotheses at all levels of organization, from individual biochemical pathways to the level of the whole organism. We demonstrate the utility of two data analysis methods, Gene Ontology profiling and rank-based statistical methods, to summarize the probable physiological function of acclimation-induced gene expression changes, and to prioritize specific genes as candidates for further study. PMID:17449823

  2. Explaining the policy impact of the 1991 and 2000 firework blasts in the Netherlands by the core of six policy change models

    OpenAIRE

    Bressers, Hans Th.A.; Lulofs, K.R.D.

    2007-01-01

    This paper presents an analysis of the aftermaths of two firework-blasts from a policy change perspective. The causes of both disasters were completely identical. Both disasters were extensively investigated and findings disseminated. After a 1991 explosion hardly any change in policy occurred while in comparison the 2000 explosion caused gigantic changes, external safety as policy issue developed and became top priority very fast. In this perspective our cases can be considered extreme cases...

  3. Calcification response to climate change in the Pliocene?

    Directory of Open Access Journals (Sweden)

    C. V. Davis

    2013-04-01

    Full Text Available As a result of anthropogenic pCO2 increases future oceans are growing warmer and lower in pH and oxygen, conditions that are likely to impact planktic communities. Past intervals of elevated and changing pCO2 and temperatures can offer a glimpse into the response of marine calcifying plankton to changes in surface oceans under conditions similar to those projected for the future. Here we present new records of planktic foraminiferal and coccolith calcification from Deep Sea Drilling Project Site 607 (mid North Atlantic and Ocean Drilling Program Site 999 (Caribbean Sea from the Pliocene, the last time that pCO2 was similar to today, and extending through a global cooling event into the Intensification of Northern Hemisphere Glaciation (3.3 to 2.6 million years ago. Test weights of both surface-dwelling foraminifera Globigerina bulloides and thermocline-dwelling foraminifera Globorotalia puncticulata vary, with a potential link to regional temperature variation in the North Atlantic, whereas in the tropics Globigerinoides ruber test weight remains stable. In contrast, reticulofenestrid coccoliths show a narrowing size range and a decline in the largest lith diameters over this interval. Our results suggest no major changes in plankton calcification during the high pCO2 Pliocene or during the transition into an icehouse world.

  4. Soil carbon responses to environmental change across temporal scales

    Science.gov (United States)

    Sierra, Carlos; Müller, Markus; Metzler, Holger

    2016-04-01

    Different biotic and abiotic factors modify the rates of soil carbon cycling at a variety of temporal scales, posing challenges in determining appropriate model abstractions to represent soil carbon dynamics in the context of global environmental change. Although a large variety of models of soil organic matter dynamics have been proposed previously, it is difficult to compare different model structures and their scale of application. We present here a mathematical framework that can be used to synthesize models with different structure, i.e. number of distinctive pools, their cycling rates and their connection. This framework can also be used to identify the scale of operability of a model and how carbon stocks and respiration fluxes would respond to external perturbations. In this contribution, we present the main concepts behind our mathematical framework and how through eigenvalue analyses we can identify the scale of operability of a model. We also present an analysis of the potential sensitivity of soil carbon stocks to changes in temperature and moisture, and identify regions with larger sensitivities to climate change. Although different models provide very diverse responses, we predict larger sensitivities of soil C stocks in humid tropical regions to increases in temperature and decreases in soil moisture.

  5. Professional relations in sport healthcare: workplace responses to organisational change.

    Science.gov (United States)

    Malcolm, Dominic; Scott, Andrea

    2011-02-01

    This article examines the impact of organisational changes in UK elite sport on the professional relations among and between different healthcare providers. The article describes the processes by which demand for elite sport healthcare has increased in the UK. It further charts the subsequent response within medicine and physiotherapy and, in particular, the institutionalisation of sport-specific sub-disciplines through the introduction of specialist qualifications. Drawing on semi-structured interviews with 14 doctors and 14 physiotherapists, the article argues that organisational changes have led to intra-professional tensions within both professional groups but in qualitatively different forms reflecting the organisational traditions and professional identities of the respective disciplines. Organisational changes promoting multi-disciplinary healthcare teams have also fostered an environment conducive to high levels of inter-professional cooperation though significant elements of inter-professional conflict remain. This study illustrates how intra-professional relations are affected by specialisation, how legitimation discourses are used by different professions, and how intra- and inter-professional conflict and cooperation should be seen as highly interdependent processes. PMID:21183266

  6. Proteome Analysis of Borrelia burgdorferi Response to Environmental Change

    Energy Technology Data Exchange (ETDEWEB)

    Angel, Thomas E.; Luft, Benjamin J.; Yang, Xiaohua; Nicora, Carrie D.; Camp, David G.; Jacobs, Jon M.; Smith, Richard D.

    2010-11-02

    We examined global changes in protein expression in the B31 strain of Borrelia burgdorferi, in response to two environmental cues (pH and temperature) chosen for their reported similarity to those encountered at different stages of the organism’s life cycle. Multidimensional nano-liquid chromatographic separations coupled with tandem mass spectrometry were used to examine the array of proteins (i.e., the proteome) of B. burgdorferi for different pH and temperature culture conditions. Changes in pH and temperature elicited in vitro adaptations of this spirochete known to cause Lyme disease and led to alterations in protein expression that are associated with increased microbial pathogenesis. We identified 1031 proteins that represent 59% of the annotated genome of B. burgdorferi and elucidated a core proteome of 414 proteins that were present in all environmental conditions investigated. Observed changes in protein abundances indicated varied replicon usage, as well as proteome functional distributions between the in vitro cell culture conditions. Surprisingly, the pH and temperature conditions that mimicked B. burgdorferi residing in the gut of a fed tick showed a marked reduction in protein diversity. Additionally, the results provide us with leading candidates for exploring how B. burgdorferi adapts to and is able to survive in a wide variety of environmental conditions and lay a foundation for planned in situ studies of B. burgdorferi isolated from the tick midgut and infected animals.

  7. Two decades of change in European general practice service profiles: conditions explaining the developments in 28 countries between 1993 and 2012.

    NARCIS (Netherlands)

    Schäfer, W.L.A.; Boerma, W.G.W.; Spreeuwenberg, P.; Schellevis, F.G.; Groenewegen, P.P.

    2016-01-01

    Objective: Evidence regarding the benefits of strong primary care has influenced health policy and practice. This study focuses on changes in the breadth of services provided by general practitioners (GPs) in Europe between 1993 and 2012 and offers possible explanations for these changes. Design: Da

  8. Can genes play a role in explaining frequent job changes? An examination of gene-environment interaction from human capital theory.

    Science.gov (United States)

    Chi, Wei; Li, Wen-Dong; Wang, Nan; Song, Zhaoli

    2016-07-01

    This study examined how a dopamine genetic marker, DRD4 7 Repeat allele, interacted with early life environmental factors (i.e., family socioeconomic status, and neighborhood poverty) to influence job change frequency in adulthood using a national representative sample from the United States. The dopamine gene played a moderating role in the relationship between early life environments and later job change behaviors, which was meditated through educational achievement. In particular, higher family socioeconomic status was associated with higher educational achievement, and thereafter higher frequency of voluntary job changes and lower frequency of involuntary job changes; such relationships were stronger (i.e., more positive or negative) for individuals with more DRD4 7R alleles. In contrast, higher neighborhood poverty was associated with lower educational achievement, and thereafter lower frequency of voluntary job change and higher frequency of involuntary job change; such relationships were again stronger (i.e., more positive or negative) for individuals with more DRD4 7R alleles. The results demonstrated that molecular genetics using DNA information, along with early life environmental factors, can bring new insights to enhance our understanding of job change frequency in individuals' early career development. (PsycINFO Database Record PMID:27077527

  9. Phenological response to climate change in China: a meta-analysis.

    Science.gov (United States)

    Ge, Quansheng; Wang, Huanjiong; Rutishauser, This; Dai, Junhu

    2015-01-01

    The change in the phenology of plants or animals reflects the response of living systems to climate change. Numerous studies have reported a consistent earlier spring phenophases in many parts of middle and high latitudes reflecting increasing temperatures with the exception of China. A systematic analysis of Chinese phenological response could complement the assessment of climate change impact for the whole Northern Hemisphere. Here, we analyze 1263 phenological time series (1960-2011, with 20+ years data) of 112 species extracted from 48 studies across 145 sites in China. Taxonomic groups include trees, shrubs, herbs, birds, amphibians and insects. Results demonstrate that 90.8% of the spring/summer phenophases time series show earlier trends and 69.0% of the autumn phenophases records show later trends. For spring/summer phenophases, the mean advance across all the taxonomic groups was 2.75 days decade(-1) ranging between 2.11 and 6.11 days decade(-1) for insects and amphibians, respectively. Herbs and amphibians show significantly stronger advancement than trees, shrubs and insect. The response of phenophases of different taxonomic groups in autumn is more complex: trees, shrubs, herbs and insects show a delay between 1.93 and 4.84 days decade(-1), while other groups reveal an advancement ranging from 1.10 to 2.11 days decade(-1) . For woody plants (including trees and shrubs), the stronger shifts toward earlier spring/summer were detected from the data series starting from more recent decades (1980s-2000s). The geographic factors (latitude, longitude and altitude) could only explain 9% and 3% of the overall variance in spring/summer and autumn phenological trends, respectively. The rate of change in spring/summer phenophase of woody plants (1960s-2000s) generally matches measured local warming across 49 sites in China (R=-0.33, P<0.05). PMID:24895088

  10. Time-lag effects of global vegetation responses to climate change.

    Science.gov (United States)

    Wu, Donghai; Zhao, Xiang; Liang, Shunlin; Zhou, Tao; Huang, Kaicheng; Tang, Bijian; Zhao, Wenqian

    2015-09-01

    Climate conditions significantly affect vegetation growth in terrestrial ecosystems. Due to the spatial heterogeneity of ecosystems, the vegetation responses to climate vary considerably with the diverse spatial patterns and the time-lag effects, which are the most important mechanism of climate-vegetation interactive effects. Extensive studies focused on large-scale vegetation-climate interactions use the simultaneous meteorological and vegetation indicators to develop models; however, the time-lag effects are less considered, which tends to increase uncertainty. In this study, we aim to quantitatively determine the time-lag effects of global vegetation responses to different climatic factors using the GIMMS3g NDVI time series and the CRU temperature, precipitation, and solar radiation datasets. First, this study analyzed the time-lag effects of global vegetation responses to different climatic factors. Then, a multiple linear regression model and partial correlation model were established to statistically analyze the roles of different climatic factors on vegetation responses, from which the primary climate-driving factors for different vegetation types were determined. The results showed that (i) both the time-lag effects of the vegetation responses and the major climate-driving factors that significantly affect vegetation growth varied significantly at the global scale, which was related to the diverse vegetation and climate characteristics; (ii) regarding the time-lag effects, the climatic factors explained 64% variation of the global vegetation growth, which was 11% relatively higher than the model ignoring the time-lag effects; (iii) for the area with a significant change trend (for the period 1982-2008) in the global GIMMS3g NDVI (P effects is quite important for better predicting and evaluating the vegetation dynamics under the background of global climate change.

  11. Correlative changes in life-history variables in response to environmental change in a model organism.

    Science.gov (United States)

    Smallegange, Isabel M; Deere, Jacques A; Coulson, Tim

    2014-06-01

    Global change alters the environment, including increases in the frequency of (un)favorable events and shifts in environmental noise color. However, how these changes impact the dynamics of populations, and whether these can be predicted accurately has been largely unexamined. Here we combine recently developed population modeling approaches and theory in stochastic demography to explore how life history, morphology, and average fitness respond to changes in the frequency of favorable environmental conditions and in the color of environmental noise in a model organism (an acarid mite). We predict that different life-history variables respond correlatively to changes in the environment, and we identify different life-history variables, including lifetime reproductive success, as indicators of average fitness and life-history speed across stochastic environments. Depending on the shape of adult survival rate, generation time can be used as an indicator of the response of populations to stochastic change, as in the deterministic case. This work is a useful step toward understanding population dynamics in stochastic environments, including how stochastic change may shape the evolution of life histories.

  12. Multimedia Modeling System Response to Regional Land Management Change

    Science.gov (United States)

    Cooter, E. J.

    2015-12-01

    A multi-media system of nitrogen and co-pollutant models describing critical physical and chemical processes that cascade synergistically and competitively through the environment, the economy and society has been developed at the USEPA Office of Research and Development. It is populated with linked or fully coupled models that address nutrient research questions such as, "How might future policy, climate or land cover change in the Mississippi River Basin affect Nitrogen and Phosphorous loadings to the Gulf of Mexico" or, "What are the management implications of regional-scale land management changes for the sustainability of air, land and water quality?" This second question requires explicit consideration of economic (e.g. sector prices) and societal (e.g. land management) factors. Metrics that illustrate biosphere-atmosphere interactions such as atmospheric PM2.5 concentrations, atmospheric N loading to surface water, soil organic N and N percolation to groundwater are calculated. An example application has been completed that is driven by a coupled agricultural and energy sector model scenario. The economic scenario assumes that by 2022 there is: 1) no detectable change in weather patterns relative to 2002; 2) a concentration of stover processing facilities in the Upper Midwest; 3) increasing offshore Pacific and Atlantic marine transportation; and 4) increasing corn, soybean and wheat production that meets future demand for food, feed and energy feedstocks. This production goal is reached without adding or removing agricultural land area whose extent is defined by the National Land Cover Dataset (NLCD) 2002v2011 classes 81 and 82. This goal does require, however, crop shifts and agricultural management changes. The multi-media system response over our U.S. 12km rectangular grid resolution analysis suggests that there are regions of potential environmental and health costs, as well as large areas that could experience unanticipated environmental and health

  13. Everglades Plant Community Response to 20th Century Hydrologic Changes

    Science.gov (United States)

    Willard, D. A.; Bernhardt, C. E.; Holmes, C. W.; Weimer, L. M.

    2002-05-01

    Pollen records in sediment cores from sites in the historic Everglades allowed us to document the natural variability of the ecosystem over the past 2,000 years and contrast it to 20th century changes in wetland plant communities. The natural system included extensive water-lily sloughs, sawgrass ridges, and scattered tree islands extending from Lake Okeechobee southward through Shark River Slough. Between ~1000 AD and 1200 AD, weedy species such as Amaranthus (water hemp) became more abundant, indicating decreased annual rainfall, shorter hydroperiods, and shallower water depths during this time. After ~1200 AD, vegetation returned to its pre-1000 AD composition. During the 20th century, two phases of hydrologic alteration occurred. Completed by 1930, the first phase included construction of the Hoover Dike, canals linking Lake Okeechobee to the Atlantic Ocean, and the Tamiami Trail. Reconstructions of plant communities indicate that these changes shortened hydroperiods and lowered water depths throughout the Everglades. The extent of water-lily slough communities decreased, and tree islands became larger in Shark River Slough. The second phase resulted from construction of canals and levees in the 1950s, creating three Water Conservation Areas. The response of plant communities to these changes varied widely depending on location in the Everglades. In Loxahatchee NWR, weedy and short-hydroperiod plant species became more abundant in marshes, and species composition of tree islands changed. In Water Conservation Area 2A, cattail replaced sawgrass in marshes with high nutrient influx; the ridge and slough structure of the marshes was replaced by more homogeneous sawgrass marshes; sustained high water levels for more than a decade resulted in loss of tree islands that had existed for more than 1,000 years. In Everglades National Park, the extent of slough vegetation decreased further. Near Florida Bay, the rate of mangrove intrusion into fresh-water marshes

  14. Neotropical vegetation responses to Younger Dryas climates as analogs for future climate change scenarios and lessons for conservation

    Science.gov (United States)

    Rull, V.; Vegas-Vilarrúbia, T.; Montoya, E.

    2015-05-01

    The Younger Dryas (YD) climatic reversal (12.86-11.65 cal ky BP), especially the warming initiated at ∼12.6 cal ky BP, and the associated vegetation changes have been proposed as past analogs to forecast the potential vegetation responses to future global warming. In this paper, we applied this model to highland and midland Neotropical localities. We used pollen analysis of lake sediments to record vegetation responses to YD climatic changes, which are reconstructed from independent paleoclimatic proxies such as the Mg/Ca ratio on foraminiferal tests and Equilibrium Line Altitude (ELA) for paleotemperature, and grayscale density and Titanium content for paleoprecipitation. Paleoclimatic reconstructions at both highlands and midlands showed a clear YD signal with a conspicuous warming extending into the early Holocene. A small percentage of taxa resulted to be sensitive to these YD climate changes. Response lags were negligible at the resolution of the study. However, changes in the sensitive taxa were relevant enough to determine changes in biodiversity and taxonomic composition. Highland vegetation experienced mainly intra-community reorganizations, whereas midland vegetation underwent major changes leading to community substitutions. This was explained in terms of threshold-crossing non-linear responses in which the coupling of climatic and other forcings (fire) was proposed as the main driving mechanism. Paleoecology provides meaningful insights on the responses of highland and midland Neotropical vegetation to the YD climatic reversal. Biotic responses at both individual (species) and collective (assemblage) levels showed patterns and processes of vegetation change useful to understand its ecological dynamics, as well as the mechanisms and external drivers involved. The use of paleoecological methods to document the biotic responses to the YD climate shifts can be useful to help forecasting the potential consequences of future global warming. Due to its quasi

  15. Modelling hydrological responses of Nerbioi River Basin to Climate Change

    Science.gov (United States)

    Mendizabal, Maddalen; Moncho, Roberto; Chust, Guillem; Torp, Peter

    2010-05-01

    Future climate change will affect aquatic systems on various pathways. Regarding the hydrological cycle, which is a very important pathway, changes in hydrometeorological variables (air temperature, precipitation, evapotranspiration) in first order impact discharges. The fourth report assessment of the Intergovernmental Panel for Climate Change indicates there is evidence that the recent warming of the climate system would result in more frequent extreme precipitation events, increased winter flood likelihoods, increased and widespread melting of snow and ice, longer and more widespread droughts, and rising sea level. Available research and climate model outputs indicate a range of hydrological impacts with likely to very likely probabilities (67 to 99%). For example, it is likely that up to 20% of the world population will live in areas where river flood potential could increase by the 2080s. In Spain, within the Atlantic basin, the hydrological variability will increase in the future due to the intensification of the positive phase of the North Atlantic Oscillation (NAO) index. This might cause flood frequency decreases, but its magnitude does not decrease. The generation of flood, its duration and magnitude are closely linked to changes in winter precipitation. The climatic conditions and relief of the Iberian Peninsula favour the generation of floods. In Spain, floods had historically strong socio-economic impacts, with more than 1525 victims in the past five decades. This upward trend of hydrological variability is expected to remain in the coming decades (medium uncertainty) when the intensification of the positive phase of the NAO index (MMA, 2006) is considered. In order to adapt or minimize climate change impacts in water resources, it is necessary to use climate projections as well as hydrological modelling tools. The main objective of this paper is to evaluate and assess the hydrological response to climate changes in flow conditions in Nerbioi river

  16. Biogeochemical responses of shallow coastal lagoons to Climate Change

    Science.gov (United States)

    Brito, A.; Newton, A.; Tett, P.; Fernandes, T.

    2009-04-01

    carefully monitored so that appropriate responses can be timely to mitigate the impacts from global change. References: Eisenreich, S.J. (2005). Climate Change and the European Water Dimension - A report to the European Water Directors. Institute for Environment and Sustainability, European Comission-Joint Research Centre. Ispra, Italy. 253pp. Kerr, R. (2008). Global warming throws some curves in the Atlantic Ocean. Science, 322, 515. IPCC (2007). Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Solomon, S., Qin, D., Manning, M., Chen, Z., Marquis, M., Averyt, K., Tignor, M., Miller, H. (eds.)]. Cambridge University Press. Cambridge, United Kingdom and New York, NY, USA, 996pp. Lloret, J., Marín, A., Marín-Guirao, L. (2008). Is coastal lagoon eutrophication likely to be aggravated by global climate change? Estuarine, Coastal and Shelf Science, 78, 403-412. Snoussi, M., Ouchani, T., Niazi, S. (2008). Vulnerability assessment of the impact of sea-level rise and flooding on the Moroccan coast: The case of the Mediterranean eastern zone. Estuarine, Coastal and Shelf Science, 77, 206-213.

  17. Resilient controls for ordering uncertain prospects change and response

    CERN Document Server

    Pham, Khanh D

    2014-01-01

    Providing readers with a detailed examination of resilient controls in risk-averse decision, this monograph is aimed toward researchers and graduate students in applied mathematics and electrical engineering with a systems-theoretic concentration. This work contains a timely and responsive evaluation of reforms on the use of asymmetry or skewness pertaining to the restrictive family of quadratic costs that have been appeared in various scholarly forums.  Additionally, the book includes a discussion of the current and ongoing efforts in the usage of risk, dynamic game decision optimization and disturbance mitigation techniques with output feedback measurements tailored toward the worst-case scenarios. This work encompasses some of the current changes across uncertainty quantification, stochastic control communities, and the creative efforts that are being made to increase the understanding of resilient controls. Specific considerations are made in this book for the application of decision theory to resilient ...

  18. The Gaia Commission: Climate Change and Moral Responsibility

    Directory of Open Access Journals (Sweden)

    Dwyer, James

    2014-11-01

    Full Text Available This short story is set in the future. In it, Francis, a retired professor of bioethics, is scheduled to appear before the Gaia Commission to account for his carbon emissions. Because his carbon emissions contributed to climate change, which harmed people and destroyed ecosystems, he is charged with recklessness, negligence, and indifference. He seems to have lived a modest and responsible life, except for the carbon emissions that he generated by flying long distances to attend ethics conferences and to give lectures. The narrator of the story is assigned to defend Francis before the Gaia Commission, so he contacts Francis to learn more about the case and to prepare a defense. The two of them examine Francis’ conduct and thinking. This fictional account raises ethical issues for all of us who have high carbon footprints, but especially for those of us who work in bioethics.

  19. Methods explained: Index numbers

    OpenAIRE

    Peter Goodridge

    2007-01-01

    Attempts to explain the subtle differences in the methodologies used to construct index numbers.Many of the statistics produced by the Office for National Statistics,particularly economic statistics, are published in the form ofindices. However, there are a number of different forms of indices and this article attempts to explain the subtle differences in themethodologies used to construct them, and also factors that feed into the choice of which type of index to use. Hypothetical examplesare...

  20. Dynamic regulation of partner abundance mediates response of reef coral symbioses to environmental change.

    Science.gov (United States)

    Cunning, R; Vaughan, N; Gillette, P; Capo, T R; Matté, J L; Baker, A C

    2015-05-01

    Regulating partner abunclance may allow symmotic organisms to mediate interaction outcomes, facilitating adaptive responses to environmental change. To explore the capacity for-adaptive regulation in an ecologically important endosymbiosis, we studied the population dynamics of symbiotic algae in reef-building corals under different abiotic contexts. We found high natural variability in symbiont abundance in corals across reefs, but this variability converged to different symbiont-specific abundances when colonies were maintained under constant conditions. When conditions changed seasonally, symbiont abundance readjusted to new equilibria. We explain these patterns using an a priori model of symbiotic costs and benefits to the coral host, which shows that the observed changes in symbiont abundance are consistent with the maximization of interaction benefit under different environmental conditions. These results indicate that, while regulating symbiont abundance helps hosts sustain maximum benefit in a dynamic environment, spatiotemporal variation in abiotic factors creates a broad range of symbiont abundances (and interaction outcomes) among corals that may account for observed natural variability in performance (e.g., growth rate) and stress tolerance (e.g., bleaching susceptibility). This cost or benefit framework provides a new perspective on the dynamic regulation of reef coral symbioses and illustrates that the dependence of interaction outcomes on biotic and abiotic contexts may be important in understanding how diverse mutualisms respond to environmental change. PMID:26236853

  1. Idiosyncratic responses of grizzly bear habitat to climate change based on projected food resource changes.

    Science.gov (United States)

    Roberts, David R; Nielsen, Scott E; Stenhouse, Gordon B

    2014-07-01

    Climate change vulnerability assessments for species of conservation concern often use species distribution and ecological niche modeling to project changes in habitat. One of many assumptions of these approaches is that food web dependencies are consistent in time and environmental space. Species at higher trophic levels that rely on the availability of species at lower trophic levels as food may be sensitive to extinction cascades initiated by changes in the habitat of key food resources. Here we assess climate change vulnerability for Ursus arctos (grizzly bears) in the southern Canadian Rocky Mountains using projected changes to 17 of the most commonly consumed plant food items. We used presence-absence information from 7088 field plots to estimate ecological niches and to project changes in future distributions of each species. Model projections indicated idiosyncratic responses among food items. Many food items persisted or even increased, although several species were found to be vulnerable based on declines or geographic shifts in suitable habitat. These included Hedysarum alpinum (alpine sweet vetch), a critical spring and autumn root-digging resource when little else is available. Potential habitat loss was also identified for three fruiting species of lower importance to bears: Empetrum nigrum (crowberry), Vaccinium scoparium (grouseberry), and Fragaria virginiana (strawberry). A general trend towards uphill migration of bear foods may result in higher vulnerability to bear populations at low elevations, which are also those that are most likely to have human-bear conflict problems. Regardless, a wide diet breadth of grizzly bears, as well as wide environmental niches of most food items, make climate change a much lower threat to grizzly bears than other bear species such as polar bears and panda bears. We cannot exclude, however, future alterations in human behavior and land use resulting from climate change that may reduce survival rates. PMID:25154102

  2. Idiosyncratic responses of grizzly bear habitat to climate change based on projected food resource changes.

    Science.gov (United States)

    Roberts, David R; Nielsen, Scott E; Stenhouse, Gordon B

    2014-07-01

    Climate change vulnerability assessments for species of conservation concern often use species distribution and ecological niche modeling to project changes in habitat. One of many assumptions of these approaches is that food web dependencies are consistent in time and environmental space. Species at higher trophic levels that rely on the availability of species at lower trophic levels as food may be sensitive to extinction cascades initiated by changes in the habitat of key food resources. Here we assess climate change vulnerability for Ursus arctos (grizzly bears) in the southern Canadian Rocky Mountains using projected changes to 17 of the most commonly consumed plant food items. We used presence-absence information from 7088 field plots to estimate ecological niches and to project changes in future distributions of each species. Model projections indicated idiosyncratic responses among food items. Many food items persisted or even increased, although several species were found to be vulnerable based on declines or geographic shifts in suitable habitat. These included Hedysarum alpinum (alpine sweet vetch), a critical spring and autumn root-digging resource when little else is available. Potential habitat loss was also identified for three fruiting species of lower importance to bears: Empetrum nigrum (crowberry), Vaccinium scoparium (grouseberry), and Fragaria virginiana (strawberry). A general trend towards uphill migration of bear foods may result in higher vulnerability to bear populations at low elevations, which are also those that are most likely to have human-bear conflict problems. Regardless, a wide diet breadth of grizzly bears, as well as wide environmental niches of most food items, make climate change a much lower threat to grizzly bears than other bear species such as polar bears and panda bears. We cannot exclude, however, future alterations in human behavior and land use resulting from climate change that may reduce survival rates.

  3. Two-stage processing of sounds explains behavioral performance variations due to changes in stimulus contrast and selective attention: an MEG study.

    Directory of Open Access Journals (Sweden)

    Jaakko Kauramäki

    Full Text Available Selectively attending to task-relevant sounds whilst ignoring background noise is one of the most amazing feats performed by the human brain. Here, we studied the underlying neural mechanisms by recording magnetoencephalographic (MEG responses of 14 healthy human subjects while they performed a near-threshold auditory discrimination task vs. a visual control task of similar difficulty. The auditory stimuli consisted of notch-filtered continuous noise masker sounds, and of 1020-Hz target tones occasionally (p = 0.1 replacing 1000-Hz standard tones of 300-ms duration that were embedded at the center of the notches, the widths of which were parametrically varied. As a control for masker effects, tone-evoked responses were additionally recorded without masker sound. Selective attention to tones significantly increased the amplitude of the onset M100 response at ~100 ms to the standard tones during presence of the masker sounds especially with notches narrower than the critical band. Further, attention modulated sustained response most clearly at 300-400 ms time range from sound onset, with narrower notches than in case of the M100, thus selectively reducing the masker-induced suppression of the tone-evoked response. Our results show evidence of a multiple-stage filtering mechanism of sensory input in the human auditory cortex: 1 one at early (~100 ms latencies bilaterally in posterior parts of the secondary auditory areas, and 2 adaptive filtering of attended sounds from task-irrelevant background masker at longer latency (~300 ms in more medial auditory cortical regions, predominantly in the left hemisphere, enhancing processing of near-threshold sounds.

  4. Variant rs1801157 in the 3'UTR of SDF-1ß does not explain variability of healthy-donor G-CSF responsiveness.

    Directory of Open Access Journals (Sweden)

    Miriam Schulz

    Full Text Available The genetics responsible for the inter-individually variable G-CSF responsiveness remain elusive. A single nucleotide polymorphism (SNP in the 3'UTR of CXCL12, rs1801157, was implicated in X4-tropic HiV susceptibility and later, in two small studies, in G-CSR responsiveness in patients and donors. The position of the SNP in the 3'UTR together with in-silico predictions suggested differential binding of micro-RNA941 as an underlying mechanism. In a cohort of 515 healthy stem cell donors we attempted to reproduce the correlation of the CXCL12 3'UTR SNP and mobilization responses and tested the role of miR941 in this context. The SNP was distributed with the expected frequency. Mobilization efficiency for CD34+ cells in WT, heterozygous and homozygous SNP individuals was indistinguishable, even after controlling for gender. miR941 expression in non-hematopoietic bone marrow cells was undetectable and miR941 did not interact with the 3' UTR of CXCL12. Proposed effects of the SNP rs1801157 on G-CSF responsiveness cannot be confirmed in a larger cohort.

  5. Explaining the erectile responses of rapists to rape stories: the contributions of sexual activity, non-consent, and violence with injury.

    Science.gov (United States)

    Harris, Grant T; Lalumière, Martin L; Seto, Michael C; Rice, Marnie E; Chaplin, Terry C

    2012-02-01

    In phallometric research, rapists have a unique pattern of erectile responses to stimuli depicting sexual activities involving coercion and violence. In this study, we attempted to determine the cues that control rapists' erectile responses to rape stories in the laboratory. A total of 12 rapists and 14 non-rapists were exposed to recorded audio scenarios that systematically varied with regard to the presence or absence of three orthogonally varied elements: sexual activity and nudity, violence and injury, and expression of non-consent. As expected from prior research, an index computed by subtracting participants' greatest mean responses to stories describing mutually consenting sexual activity from their greatest mean responses to stories describing rape was much higher among rapists than non-rapists. Both groups showed larger responses when stories involved sexual activity and nudity, but neither group exhibited a preference for cues of violence and serious injury, or for cues of non-consent. The element that produced the larger group difference, however, was the presence or absence of active consent. The results indicated that a sexual interest in (or indifference to) non-consent is at least as central to accounting for the unique sexual orientation of rapists as is sexual responding to violence and injury. PMID:22415328

  6. Venezuelan policies and responses on climate change and natural hazards

    Science.gov (United States)

    Caponi, Claudio; Rosales, Anibal

    1992-06-01

    Venezuela is an intertropical country which has the fortune not to suffer the severities of natural hazards which are usual in other countries of this region. It is a developing country, whose economy is heavily dependent on oil production and exports. Its greenhouse gas emissions are relatively low, but it is expected that the planned industrialization development will bring an associated increase in emissions. As a nation, Venezuela has a highly developed environmental consciousness. The Ministry of environment, the first in Latin America, was created in 1977, and has been the main contributor to the national policy of Disaster Prevention and Reduction. As in many developing countries actions and responses in this regard have been rather limited in scope, and even though legislation has been developed, many problems arise for its enforcement. Several local warning systems, civil defense procedures, and infrastructural protection measures are operational, however they have not been designed, revised, or planned taking into consideration the potential impacts of climate change. Presently Venezuela is an active participant state in the negotiation for a framework convention on climate change. That is a very difficult negotiation for our country. Here we have to conciliate enviromental principles with national economic interests. The elements of our position in this contex are presented in this statement.

  7. Stationary monitoring of glacier response to climate change in China

    Science.gov (United States)

    Ren, Jiawen; Li, Zhongqin; Qin, Xiang; He, Yuanqing; He, Xiaobo; Li, Huilin

    2016-04-01

    At present, there are about 48571 glaciers with a total area of about 51.8×103 km2 and a volume of about 5.6×103 km3 in China. They are distributed widely in the high mountains in and surrounding the Tibetan Plateau and other high mountains such as Tianshan, Altay and Pamir. In view of differences in climatic conditions and glacier types, stationary monitoring of the glacier variations has been ongoing in different regions in order to investigate the glacier response to climate change. The monitoring results show that all the monitoring glaciers have been in retreat during the past decades and especially since 1990's the retreat rate has an accelerating trend. The accumulative mass balance is much negative and has a large annual variability for the monsoonal maritime glaciers in comparison with the continental and sub-continental glaciers. Under climate warming background, the acceleration of glacier melting is mainly attributed to rise in air temperature, ice temperature augment and albedo reduction of glacier surface. Particularly, the albedo reduction has a positive feedback effect on the glacier melting. Based on long term observation of glacier variations and physical properties, a simple dynamics model is coupled with mass balance modeling to make a projection of a typical glacier change in future. The primary modeling results suggest that the glacier will continue in shrinkage until vanishing within 50-90 years.

  8. Adaptation responses to climate change differ between global megacities

    Science.gov (United States)

    Georgeson, Lucien; Maslin, Mark; Poessinouw, Martyn; Howard, Steve

    2016-06-01

    Urban areas are increasingly at risk from climate change, with negative impacts predicted for human health, the economy and ecosystems. These risks require responses from cities to improve their resilience. Policymakers need to understand current adaptation spend to plan comprehensively and effectively. Through the measurement of spend in the newly defined `adaptation economy', we analyse current climate change adaptation efforts in ten megacities. In all cases, the adaptation economy remains a small part of the overall economy, representing a maximum of 0.33% of a city's gross domestic product (here referred to as GDPc). Differences in total spend are significant between cities in developed, emerging and developing countries, ranging from #15 million to #1,600 million. Comparing key subsectors, we demonstrate the differences in adaptation profiles. Developing cities have higher proportional spend on health and agriculture, whereas developed cities have higher spend on energy and water. Spend per capita and percentage of GDPc comparisons more clearly show disparities between cities. Developing country cities spend half the proportion of GDPc and significantly less per capita, suggesting that adaptation spend is driven by wealth rather than the number of vulnerable people. This indicates that current adaptation activities are insufficient in major population centres in developing and emerging economies.

  9. Downward Wave Coupling Changes in Response to Future Climate Change, Two Way Atmosphere/Ocean Coupling and QBO

    Science.gov (United States)

    Wellyanto Lubis, Sandro; Matthes, Katja; Harnik, Nili; Omrani, Nour-Eddine

    2014-05-01

    Wave reflection in the stratosphere can impact the troposphere via a well-defined, high latitude meridional waveguide that is bounded above by a vertical reflecting surface. Such wave reflection is known as downward wave coupling (DWC). Recent studies have shown that stratospheric ozone affects DWC, affecting wave propagation and subsequent wave-mean flow interaction in the Southern Hemisphere. However the factors controlling DWC in the Northern Hemisphere are still unclear. There is new evidence that the frequency of Major Stratospheric Warming (MSW) is significantly influenced by the QBO and two-way ocean/ atmosphere interaction. However the resulting impact on DWC has thus far not been investigated. Here we examine the impact of future climate change, two way atmosphere/ ocean coupling, and the QBO on wave geometry and DWC using different CESM-WACCM model experiments. A transient simulation of present and future climate (1955-2099), with green house gases (GHG) and ozone depleting substances (ODS) following the RCP 8.5 scenario, shows the largest reduction in the DWC over last few decades of the simulation. This reduction is associated with an absence of the vertical reflecting surface and statistically insignificant downward wave reflection. Comparison to an experiment with GHG/ODS fixed at 1960s levels, shows no indication of DWC-changes. The lack of a DWC response is associated with insignificant changes of the background wind states, whose vertical structure directly impacts the DWC. The comparison of this experiment with simulations with and without QBO nudging shows that the QBO strengthens the DWC. This can be explained by the fact that our nonQBO simulation has a permanent, strong QBO-like east phase, which dampens the DWC. Comparison of experiments with dynamically-coupled and fixed SSTs shows that the background zonal wind is strengthened significantly when the ocean/atmosphere interaction is removed. However, no apparent strengthening of DWC is seen

  10. Pathways of change explaining the effect of smoke-free legislation on smoking cessation in the Netherlands: an application of the international tobacco control conceptual model

    NARCIS (Netherlands)

    G.E. Nagelhout; H. de Vries; G.T. Fong; M.J.J.M. Candel; J.F. Thrasher; B. van den Putte; M.E. Thompson; K.M. Cummings; M.C. Willemsen

    2012-01-01

    Introduction: This study aims to test the pathways of change from individual exposure to smoke-free legislation on smoking cessation, as hypothesized in the International Tobacco Control (ITC) Conceptual Model. Methods: A nationally representative sample of Dutch smokers aged 15 years and older was

  11. Can Recent Global Changes Explain the Dramatic Range Contraction of an Endangered Semi-Aquatic Mammal Species in the French Pyrenees?

    Science.gov (United States)

    Charbonnel, Anaïs; Laffaille, Pascal; Biffi, Marjorie; Blanc, Frédéric; Maire, Anthony; Némoz, Mélanie; Sanchez-Perez, José Miguel; Sauvage, Sabine

    2016-01-01

    Species distribution models (SDMs) are the main tool to predict global change impacts on species ranges. Climate change alone is frequently considered, but in freshwater ecosystems, hydrology is a key driver of the ecology of aquatic species. At large scale, hydrology is however rarely accounted for, owing to the lack of detailed stream flow data. In this study, we developed an integrated modelling approach to simulate stream flow using the hydrological Soil and Water Assessment Tool (SWAT). Simulated stream flow was subsequently included as an input variable in SDMs along with topographic, hydrographic, climatic and land-cover descriptors. SDMs were applied to two temporally-distinct surveys of the distribution of the endangered Pyrenean desman (Galemys pyrenaicus) in the French Pyrenees: a historical one conducted from 1985 to 1992 and a current one carried out between 2011 and 2013. The model calibrated on historical data was also forecasted onto the current period to assess its ability to describe the distributional change of the Pyrenean desman that has been modelled in the recent years. First, we found that hydrological and climatic variables were the ones influencing the most the distribution of this species for both periods, emphasizing the importance of taking into account hydrology when SDMs are applied to aquatic species. Secondly, our results highlighted a strong range contraction of the Pyrenean desman in the French Pyrenees over the last 25 years. Given that this range contraction was under-estimated when the historical model was forecasted onto current conditions, this finding suggests that other drivers may be interacting with climate, hydrology and land-use changes. Our results imply major concerns for the conservation of this endemic semi-aquatic mammal since changes in climate and hydrology are expected to become more intense in the future. PMID:27467269

  12. Abundance changes and habitat availability drive species' responses to climate change

    Science.gov (United States)

    Mair, Louise; Hill, Jane K.; Fox, Richard; Botham, Marc; Brereton, Tom; Thomas, Chris D.

    2014-02-01

    There is little consensus as to why there is so much variation in the rates at which different species' geographic ranges expand in response to climate warming. Here we show that the relative importance of species' abundance trends and habitat availability for British butterfly species vary over time. Species with high habitat availability expanded more rapidly from the 1970s to mid-1990s, when abundances were generally stable, whereas habitat availability effects were confined to the subset of species with stable abundances from the mid-1990s to 2009, when abundance trends were generally declining. This suggests that stable (or positive) abundance trends are a prerequisite for range expansion. Given that species' abundance trends vary over time for non-climatic as well as climatic reasons, assessment of abundance trends will help improve predictions of species' responses to climate change, and help us to understand the likely success of different conservation strategies for facilitating their expansions.

  13. Peptide motifs of the single dominantly expressed class I molecule explain the striking MHC-determined response to Rous sarcoma virus in chickens

    DEFF Research Database (Denmark)

    Wallny, Hans-Joachim; Avila, David; Hunt, Lawrence G.;

    2006-01-01

    are consistent with the peptides binding to models of the class I molecule encoded by the abundant cDNA. Finally, having shown for three haplotypes that there is a single dominantly expressed class I molecule at the level of RNA, protein, and antigenic peptide, we show that the motifs can explain the striking......Compared with the MHC of typical mammals, the chicken MHC is smaller and simpler, with only two class I genes found in the B12 haplotype. We make five points to show that there is a single-dominantly expressed class I molecule that can have a strong effect on MHC function. First, we find only one cDNA...... for two MHC haplotypes (B14 and B15) and cDNAs corresponding to two genes for the other six (B2, B4, B6, B12, B19, and B21). Second, we find, for the B4, B12, and B15 haplotypes, that one cDNA is at least 10-fold more abundant than the other. Third, we use 2D gel electrophoresis of class I molecules from...

  14. Gut response induced by weaning in piglet features marked changes in immune and inflammatory response.

    Science.gov (United States)

    Bomba, Lorenzo; Minuti, Andrea; Moisá, Sonia J; Trevisi, Erminio; Eufemi, Elisa; Lizier, Michela; Chegdani, Fatima; Lucchini, Franco; Rzepus, Marcin; Prandini, Aldo; Rossi, Filippo; Mazza, Raffaele; Bertoni, Giuseppe; Loor, Juan J; Ajmone-Marsan, Paolo

    2014-12-01

    At weaning, piglets are exposed to many stressors, such as separation from the sow, mixing with other litters, end of lactational immunity, and a change in their environment and gut microbiota. The sudden change of feeding regime after weaning causes morphological and histological changes in the small intestine which are critical for the immature digestive system. Sixteen female piglets were studied to assess the effect of sorbic acid supplementation on the small intestine tissue transcriptome. At weaning day (T0, piglet age 28 days), four piglets were sacrificed and ileal tissue samples collected. The remaining 12 piglets were weighed and randomly assigned to different postweaning (T5, piglet age 33 days) diets. Diet A (n = 6) contained 5 g/kg of sorbic acid. In diet B (n = 6), the organic acids were replaced by barley flour. Total RNA was isolated and then hybridized to CombiMatrix CustomArray™ 90-K platform microarrays, screening about 30 K genes. Even though diet had no detectable effect on the transcriptome during the first 5 days after weaning, results highlighted some of the response mechanisms to the stress of weaning occurring in the piglet gut. A total of 205 differentially expressed genes were used for functional analysis using the bioinformatics tools BLAST2GO, Ingenuity Pathway Analysis 8.0, and Dynamic Impact Approach (DIA). Bioinformatic analysis revealed that apoptosis, RIG-I-like, and NOD-like receptor signaling were altered as a result of weaning. Interferons and caspases gene families were the most activated after weaning in response to piglets to multiple stressors. Results suggest that immune and inflammatory responses were activated and likely are a cause of small intestine atrophy as revealed by a decrease in villus height and villus/crypt ratio.

  15. Fungal-mediated mortality explains the different effects of dung leachates on the germination response of grazing increaser and decreaser species

    Science.gov (United States)

    Carmona, Carlos P.; Navarro, Elena; Peco, Begoña

    2016-01-01

    Depending on their response to grazing, grassland species can be categorized as grazing increasers or decreasers. Grazing by livestock includes several different activities that can impact species differently. Recent evidence suggest that one of these actions, dung deposition, can reduce the germinative performance of decreaser species, thus favouring increasers. The present study tested the hypothesis that decreased germinative success of decreaser species is caused by a greater activity of fungal pathogens under the influence of dung leachates. We performed a phytotron experiment analysing the germination and fungal infections of fourteen species from Mediterranean grasslands. Species were grouped into phylogenetically-related pairs, composed of an increaser and a decreaser species. Seeds of each species were germinated under four different treatments (control, dung leachate addition, fungicide addition and dung leachate and fungicide addition), and the differences in germination percentage, germination speed and infection rate between each increaser species and its decreaser counterpart were analysed. Decreaser species were more affected by mortality than increaser ones, and these differences were higher under the presence of dung leachates. The differences in germinative performance after excluding the effect of seed mortality did not differ between treatments, showing that the main mechanism by which dung leachates favour increaser species is through increased mortality of the seeds of decreaser species. Drastic reductions in the number of dead seeds in the treatments including fungicide addition further revealed that fungal pathogens are responsible for these differences between species with different grazing response. The different vulnerabilities of increaser and decreaser species to the increased activity of fungal pathogens under the presence of dung leachates seems the main reason behind the differential effect of these leachates on species with

  16. A streamflow routing approach to address temporal change in streamflow response

    Science.gov (United States)

    Åkesson, Anna; Wörman, Anders

    2015-04-01

    Temporal variation in the statistical characteristics of the discharge time-series can be noticed in several Swedish catchments where discharge has been measured for a long time period (~100 years). As the trend and its magnitude, can be different in catchments with geographic proximity, the investigated hypothesis is that the temporal change is, at least to some extent, caused by changes in the properties of the stream network. As changing the hydraulic mechanisms within the stream network will have a profound effect on the streamflow response, the primary emphasis in this study is on how stream network structure (distribution and topology of stream reaches) has changed over time. The study is performed by setting up a distributed routing model for the stream network in its present geographic distribution as well as for distribution which has been obtained from historic maps that has been digitized. The travel time distribution through the stream network in the past and present case can thus be used as a descriptor to partly explain how the streamflow response has changed temporally. By use of a distributed routing model based in hydromechanical relationships of energy and momentum, applied to a stream network, velocities are derived at quasi-stationary conditions for a range of discharges, reflecting the prevailing hydraulic mechanisms within stream networks. In the proposed methodology; backwater effects are also included as the downstream boundary conditions (water levels and velocity) are used when determining the slope of the energy line. The results from the distributed routing model are primarily used to interpret the temporal variation in the statistical characteristics of the discharge time-series. Also, the results from the distributed routing modelling can be used as physically based parameters for the streamflow component of a hydrologic model, as the routing model gives rise to a catchment-specific, unambiguous relationship between mean travel time

  17. Explaining the Interpretive Mind.

    Science.gov (United States)

    Brockmeier, Jens

    1996-01-01

    Examines two prominent positions in the epistemological foundations of psychology--Piaget's causal explanatory claims and Vygotsky's interpretive understanding; contends that they need to be placed in their wider philosophical contexts. Argues that the danger of causally explaining cultural practices through which human beings construct and…

  18. The wireless internet explained

    CERN Document Server

    Rhoton, John

    2001-01-01

    The Wireless Internet Explained covers the full spectrum of wireless technologies from a wide range of vendors, including initiatives by Microsoft and Compaq. The Wireless Internet Explained takes a practical look at wireless technology. Rhoton explains the concepts behind the physics, and provides an overview that clarifies the convoluted set of standards heaped together under the umbrella of wireless. It then expands on these technical foundations to give a panorama of the increasingly crowded landscape of wireless product offerings. When it comes to actual implementation the book gives abundant down-to-earth advice on topics ranging from the selection and deployment of mobile devices to the extremely sensitive subject of security.Written by an expert on Internet messaging, the author of Digital Press''s successful Programmer''s Guide to Internet Mail and X.400 and SMTP: Battle of the E-mail Protocols, The Wireless Internet Explained describes and evaluates the current state of the fast-growing and crucial...

  19. Structural differences between rye and wheat breads but not total fiber content may explain the lower postprandial insulin response to rye bread

    DEFF Research Database (Denmark)

    Juntunen, Katri S; Laaksonen, David E; Autio, Karin;

    2003-01-01

    -fiber rye bread; each bread provided 50 g available carbohydrate and was served with breakfast. Plasma glucose, insulin, glucose-dependent insulinotropic polypeptide, glucagon-like peptide 1, and serum C-peptide were measured in fasting and 8 postprandial blood samples. In vitro starch hydrolysis...... breads were found. Glucose and glucagon-like peptide 1 responses to the rye breads were not significantly different from those to the control, except at 150 and 180 min. In vitro starch hydrolysis was slower in all rye breads than in the control, and the structure of continuous matrix and starch granules...

  20. Respiratory Changes in Response to Cognitive Load: A Systematic Review.

    Science.gov (United States)

    Grassmann, Mariel; Vlemincx, Elke; von Leupoldt, Andreas; Mittelstädt, Justin M; Van den Bergh, Omer

    2016-01-01

    When people focus attention or carry out a demanding task, their breathing changes. But which parameters of respiration vary exactly and can respiration reliably be used as an index of cognitive load? These questions are addressed in the present systematic review of empirical studies investigating respiratory behavior in response to cognitive load. Most reviewed studies were restricted to time and volume parameters while less established, yet meaningful parameters such as respiratory variability have rarely been investigated. The available results show that respiratory behavior generally reflects cognitive processing and that distinct parameters differ in sensitivity: While mentally demanding episodes are clearly marked by faster breathing and higher minute ventilation, respiratory amplitude appears to remain rather stable. The present findings further indicate that total variability in respiratory rate is not systematically affected by cognitive load whereas the correlated fraction decreases. In addition, we found that cognitive load may lead to overbreathing as indicated by decreased end-tidal CO2 but is also accompanied by elevated oxygen consumption and CO2 release. However, additional research is needed to validate the findings on respiratory variability and gas exchange measures. We conclude by outlining recommendations for future research to increase the current understanding of respiration under cognitive load. PMID:27403347

  1. Geochemically induced shifts in catabolic energy yields explain past ecological changes of diffuse vents in the East Pacific Rise 9°50'N area

    Directory of Open Access Journals (Sweden)

    Hentscher Michael

    2012-01-01

    Full Text Available Abstract The East Pacific Rise (EPR at 9°50'N hosts a hydrothermal vent field (Bio9 where the change in fluid chemistry is believed to have caused the demise of a tubeworm colony. We test this hypothesis and expand on it by providing a thermodynamic perspective in calculating free energies for a range of catabolic reactions from published compositional data. The energy calculations show that there was excess H2S in the fluids and that oxygen was the limiting reactant from 1991 to 1997. Energy levels are generally high, although they declined in that time span. In 1997, sulfide availability decreased substantially and H2S was the limiting reactant. Energy availability dropped by a factor of 10 to 20 from what it had been between 1991 and 1995. The perishing of the tubeworm colonies began in 1995 and coincided with the timing of energy decrease for sulfide oxidizers. In the same time interval, energy availability for iron oxidizers increased by a factor of 6 to 8, and, in 1997, there was 25 times more energy per transferred electron in iron oxidation than in sulfide oxidation. This change coincides with a massive spread of red staining (putative colonization by Fe-oxidizing bacteria between 1995 and 1997. For a different cluster of vents from the EPR 9°50'N area (Tube Worm Pillar, thermodynamic modeling is used to examine changes in subseafloor catabolic metabolism between 1992 and 2000. These reactions are deduced from deviations in diffuse fluid compositions from conservative behavior of redox-sensitive species. We show that hydrogen is significantly reduced relative to values expected from conservative mixing. While H2 concentrations of the hydrothermal endmember fluids were constant between 1992 and 1995, the affinities for hydrogenotrophic reactions in the diffuse fluids decreased by a factor of 15 and then remained constant between 1995 and 2000. Previously, these fluids have been shown to support subseafloor methanogenesis. Our

  2. Responses of Grassland and Forest to Temperature and Precipitation Changes in Northeast China

    Institute of Scientific and Technical Information of China (English)

    PENG Jing; DONG Wenjie; YUAN Wenping; ZHANG Yong

    2012-01-01

    Using the Normalized Difference Vegetation Index (NDVI) as an indicator of vegetation growth,we explored the characteristics and differences in the response to drought of five vegetation biomes in Northeast China,including typical steppe,desert steppe,meadow steppe,deciduous coniferous forest and deciduous broad-leaved forest during the period 1982 2009.The results indicate that growing season precipitation may be the primary vegetation growth-limiting factor in grasslands.More than 70% of the temporal variations in NDVI can be explained by the amount of precipitation during the growing season in typical and desert steppes.During the same period,the mean temperature in the growing season could explain nearly 43% of the variations in the mean growing season NDVI and is therefore a dominant growth-limiting factor for forest ecosystems.Therefore,the NDVI trends differ largely due to differences in the vegetation growth-limiting factors of the different vegetation biomes.The NDVI responses to droughts vary in magnitude and direction and depend on the drought-affected areas of the five vegetation types.Specifically,the changes in NDVI are consistent with the variations in precipitation for grassland ecosystems.A lack of precipitation resulted in decreases in NDVI,thereby reducing vegetation growth in these regions.Conversely,increasing precipitation decreased the NDVI of forest ecosystems.The results also suggest that grasslands under arid and semi-arid environments may be more sensitive to drought than forests under humid environments.Among grassland ecosystems,desert steppe was most sensitive to drought,followed by typical steppe; meadow steppe was the least sensitive.

  3. Relaxation response induces temporal transcriptome changes in energy metabolism, insulin secretion and inflammatory pathways.

    Directory of Open Access Journals (Sweden)

    Manoj K Bhasin

    Full Text Available The relaxation response (RR is the counterpart of the stress response. Millennia-old practices evoking the RR include meditation, yoga and repetitive prayer. Although RR elicitation is an effective therapeutic intervention that counteracts the adverse clinical effects of stress in disorders including hypertension, anxiety, insomnia and aging, the underlying molecular mechanisms that explain these clinical benefits remain undetermined. To assess rapid time-dependent (temporal genomic changes during one session of RR practice among healthy practitioners with years of RR practice and also in novices before and after 8 weeks of RR training, we measured the transcriptome in peripheral blood prior to, immediately after, and 15 minutes after listening to an RR-eliciting or a health education CD. Both short-term and long-term practitioners evoked significant temporal gene expression changes with greater significance in the latter as compared to novices. RR practice enhanced expression of genes associated with energy metabolism, mitochondrial function, insulin secretion and telomere maintenance, and reduced expression of genes linked to inflammatory response and stress-related pathways. Interactive network analyses of RR-affected pathways identified mitochondrial ATP synthase and insulin (INS as top upregulated critical molecules (focus hubs and NF-κB pathway genes as top downregulated focus hubs. Our results for the first time indicate that RR elicitation, particularly after long-term practice, may evoke its downstream health benefits by improving mitochondrial energy production and utilization and thus promoting mitochondrial resiliency through upregulation of ATPase and insulin function. Mitochondrial resiliency might also be promoted by RR-induced downregulation of NF-κB-associated upstream and downstream targets that mitigates stress.

  4. Relaxation response induces temporal transcriptome changes in energy metabolism, insulin secretion and inflammatory pathways.

    Science.gov (United States)

    Bhasin, Manoj K; Dusek, Jeffery A; Chang, Bei-Hung; Joseph, Marie G; Denninger, John W; Fricchione, Gregory L; Benson, Herbert; Libermann, Towia A

    2013-01-01

    The relaxation response (RR) is the counterpart of the stress response. Millennia-old practices evoking the RR include meditation, yoga and repetitive prayer. Although RR elicitation is an effective therapeutic intervention that counteracts the adverse clinical effects of stress in disorders including hypertension, anxiety, insomnia and aging, the underlying molecular mechanisms that explain these clinical benefits remain undetermined. To assess rapid time-dependent (temporal) genomic changes during one session of RR practice among healthy practitioners with years of RR practice and also in novices before and after 8 weeks of RR training, we measured the transcriptome in peripheral blood prior to, immediately after, and 15 minutes after listening to an RR-eliciting or a health education CD. Both short-term and long-term practitioners evoked significant temporal gene expression changes with greater significance in the latter as compared to novices. RR practice enhanced expression of genes associated with energy metabolism, mitochondrial function, insulin secretion and telomere maintenance, and reduced expression of genes linked to inflammatory response and stress-related pathways. Interactive network analyses of RR-affected pathways identified mitochondrial ATP synthase and insulin (INS) as top upregulated critical molecules (focus hubs) and NF-κB pathway genes as top downregulated focus hubs. Our results for the first time indicate that RR elicitation, particularly after long-term practice, may evoke its downstream health benefits by improving mitochondrial energy production and utilization and thus promoting mitochondrial resiliency through upregulation of ATPase and insulin function. Mitochondrial resiliency might also be promoted by RR-induced downregulation of NF-κB-associated upstream and downstream targets that mitigates stress. PMID:23650531

  5. Modelling contrasting responses of wetland productivity to changes in water table depth

    Directory of Open Access Journals (Sweden)

    R. F. Grant

    2012-11-01

    declined with increasing WTD in a year with a shallow water table, but rose in a year with a deeper one. The model thus provided an integrated set of hypotheses for explaining site-specific and sometimes contrasting responses of wetland productivity to changes in WTD as found in different field experiments.

  6. Modelling contrasting responses of wetland productivity to changes in water table depth

    Directory of Open Access Journals (Sweden)

    R. F. Grant

    2012-05-01

    declined with increasing WTD in a year with a shallow water table, but rose in a year with a deeper one. The model thus provided an integrated set of hypotheses for explaining site-specific and sometimes contrasting responses of wetland productivity to changes in WTD as found in different field experiments.

  7. Modelling Contrasting Responses of Wetland Productivity to Changes in Water Table Depth

    Science.gov (United States)

    Grant, R. F.; Desai, A. R.; Sulman, B. N.

    2012-12-01

    set of hypotheses for explaining site-specific and sometimes contrasting responses of wetland productivity to changes in WTD as found in different field experiments.

  8. Terrestrial Ecosystem Responses to Global Change: A Research Strategy

    Energy Technology Data Exchange (ETDEWEB)

    Ecosystems Working Group,

    1998-09-23

    Uncertainty about the magnitude of global change effects on terrestrial ecosystems and consequent feedbacks to the atmosphere impedes sound policy planning at regional, national, and global scales. A strategy to reduce these uncertainties must include a substantial increase in funding for large-scale ecosystem experiments and a careful prioritization of research efforts. Prioritization criteria should be based on the magnitude of potential changes in environmental properties of concern to society, including productivity; biodiversity; the storage and cycling of carbon, water, and nutrients; and sensitivity of specific ecosystems to environmental change. A research strategy is proposed that builds on existing knowledge of ecosystem responses to global change by (1) expanding the spatial and temporal scale of experimental ecosystem manipulations to include processes known to occur at large scales and over long time periods; (2) quantifying poorly understood linkages among processes through the use of experiments that manipulate multiple interacting environmental factors over a broader range of relevant conditions than did past experiments; and (3) prioritizing ecosystems for major experimental manipulations on the basis of potential positive and negative impacts on ecosystem properties and processes of intrinsic and/or utilitarian value to humans and on feedbacks of terrestrial ecosystems to the atmosphere. Models and experiments are equally important for developing process-level understanding into a predictive capability. To support both the development and testing of mechanistic ecosystem models, a two-tiered design of ecosystem experiments should be used. This design should include both (1) large-scale manipulative experiments for comprehensive testing of integrated ecosystem models and (2) multifactor, multilevel experiments for parameterization of process models across the critical range of interacting environmental factors (CO{sub 2}, temperature, water

  9. Can Science `explain' Consciousness ?

    OpenAIRE

    Samal, M. K.

    2000-01-01

    Consciousness is the process by which one attributes `meaning' to the world. Considering F$\\phi$llesdal's definition of `meaning' as the joint product of all `evidence' that is available to those who `communicate', we conclude that science can, not only reduce all the {\\em evidence} to a Basic Entity (we call BE), but also can `explain' consciousness once a suitable definition for {\\em communication} is found that exploits the quantum superposition principle to incorporate the fuzzyness of ou...

  10. Phenotypic variation in Aicardi-Goutières syndrome explained by cell-specific IFN-stimulated gene response and cytokine release.

    Science.gov (United States)

    Cuadrado, Eloy; Michailidou, Iliana; van Bodegraven, Emma J; Jansen, Machiel H; Sluijs, Jacqueline A; Geerts, Dirk; Couraud, Pierre-Olivier; De Filippis, Lidia; Vescovi, Angelo L; Kuijpers, Taco W; Hol, Elly M

    2015-04-15

    Aicardi-Goutières syndrome (AGS) is a monogenic inflammatory encephalopathy caused by mutations in TREX1, RNASEH2A, RNASEH2B, RNASEH2C, SAMHD1, ADAR1, or MDA5. Mutations in those genes affect normal RNA/DNA intracellular metabolism and detection, triggering an autoimmune response with an increase in cerebral IFN-α production by astrocytes. Microangiopathy and vascular disease also contribute to the neuropathology in AGS. In this study, we report that AGS gene silencing of TREX1, SAMHD1, RNASEH2A, and ADAR1 by short hairpin RNAs in human neural stem cell-derived astrocytes, human primary astrocytes, and brain-derived endothelial cells leads to an antiviral status of these cells compared with nontarget short hairpin RNA-treated cells. We observed a distinct activation of the IFN-stimulated gene signature with a substantial increase in the release of proinflammatory cytokines (IL-6) and chemokines (CXCL10 and CCL5). A differential impact of AGS gene silencing was noted; silencing TREX1 gave rise to the most dramatic in both cell types. Our findings fit well with the observation that patients carrying mutations in TREX1 experience an earlier onset and fatal outcome. We provide in the present study, to our knowledge for the first time, insight into how astrocytic and endothelial activation of antiviral status may differentially lead to cerebral pathology, suggesting a rational link between proinflammatory mediators and disease severity in AGS.

  11. Hydrogen isotope response to changing salinity and rainfall in Australian mangroves.

    Science.gov (United States)

    Ladd, S Nemiah; Sachs, Julian P

    2015-12-01

    Hydrogen isotope ratios ((2) H/(1) H, δ(2) H) of leaf waxes covary with those in precipitation and are therefore a useful paleohydrologic proxy. Mangroves are an exception to this relationship because their δ(2) H values are also influenced by salinity. The mechanisms underlying this response were investigated by measuring leaf lipid δ(2) H and leaf and xylem water δ(2) H and δ(18) O values from three mangrove species over 9.5 months in a subtropical Australian estuary. Net (2) H/(1) H fractionation between surface water and leaf lipids decreased by 0.5-1.0‰ ppt(-1) for n-alkanes and 0.4-0.8‰ ppt(-1) for isoprenoids. Xylem water was (2) H depleted relative to surface water, reflecting (2) H discrimination of 4-10‰ during water uptake at all salinities and opportunistic uptake of freshwater at high salinity. However, leaf water (2) H enrichment relative to estuary water was insensitive to salinity and identical for all species. Therefore, variations in leaf and xylem water δ(2) H values cannot explain the salinity-dependent (2) H depletion in leaf lipids, nor the 30‰ range in leaf lipid δ(2) H values among species. Biochemical changes in direct response to salt stress, such as increased compatible solute production or preferential use of stored carbohydrates, and/or the timing of lipid production and subsequent turnover rates, are more likely causes.

  12. A New Computational Model for Neuro-Glio-Vascular Coupling: Astrocyte Activation Can Explain Cerebral Blood Flow Nonlinear Response to Interictal Events.

    Science.gov (United States)

    Blanchard, Solenna; Saillet, Sandrine; Ivanov, Anton; Benquet, Pascal; Bénar, Christian-George; Pélégrini-Issac, Mélanie; Benali, Habib; Wendling, Fabrice

    2016-01-01

    Developing a clear understanding of the relationship between cerebral blood flow (CBF) response and neuronal activity is of significant importance because CBF increase is essential to the health of neurons, for instance through oxygen supply. This relationship can be investigated by analyzing multimodal (fMRI, PET, laser Doppler…) recordings. However, the important number of intermediate (non-observable) variables involved in the underlying neurovascular coupling makes the discovery of mechanisms all the more difficult from the sole multimodal data. We present a new computational model developed at the population scale (voxel) with physiologically relevant but simple equations to facilitate the interpretation of regional multimodal recordings. This model links neuronal activity to regional CBF dynamics through neuro-glio-vascular coupling. This coupling involves a population of glial cells called astrocytes via their role in neurotransmitter (glutamate and GABA) recycling and their impact on neighboring vessels. In epilepsy, neuronal networks generate epileptiform discharges, leading to variations in astrocytic and CBF dynamics. In this study, we took advantage of these large variations in neuronal activity magnitude to test the capacity of our model to reproduce experimental data. We compared simulations from our model with isolated epileptiform events, which were obtained in vivo by simultaneous local field potential and laser Doppler recordings in rats after local bicuculline injection. We showed a predominant neuronal contribution for low level discharges and a significant astrocytic contribution for higher level discharges. Besides, neuronal contribution to CBF was linear while astrocytic contribution was nonlinear. Results thus indicate that the relationship between neuronal activity and CBF magnitudes can be nonlinear for isolated events and that this nonlinearity is due to astrocytic activity, highlighting the importance of astrocytes in the

  13. A New Computational Model for Neuro-Glio-Vascular Coupling: Astrocyte Activation Can Explain Cerebral Blood Flow Nonlinear Response to Interictal Events.

    Directory of Open Access Journals (Sweden)

    Solenna Blanchard

    Full Text Available Developing a clear understanding of the relationship between cerebral blood flow (CBF response and neuronal activity is of significant importance because CBF increase is essential to the health of neurons, for instance through oxygen supply. This relationship can be investigated by analyzing multimodal (fMRI, PET, laser Doppler… recordings. However, the important number of intermediate (non-observable variables involved in the underlying neurovascular coupling makes the discovery of mechanisms all the more difficult from the sole multimodal data. We present a new computational model developed at the population scale (voxel with physiologically relevant but simple equations to facilitate the interpretation of regional multimodal recordings. This model links neuronal activity to regional CBF dynamics through neuro-glio-vascular coupling. This coupling involves a population of glial cells called astrocytes via their role in neurotransmitter (glutamate and GABA recycling and their impact on neighboring vessels. In epilepsy, neuronal networks generate epileptiform discharges, leading to variations in astrocytic and CBF dynamics. In this study, we took advantage of these large variations in neuronal activity magnitude to test the capacity of our model to reproduce experimental data. We compared simulations from our model with isolated epileptiform events, which were obtained in vivo by simultaneous local field potential and laser Doppler recordings in rats after local bicuculline injection. We showed a predominant neuronal contribution for low level discharges and a significant astrocytic contribution for higher level discharges. Besides, neuronal contribution to CBF was linear while astrocytic contribution was nonlinear. Results thus indicate that the relationship between neuronal activity and CBF magnitudes can be nonlinear for isolated events and that this nonlinearity is due to astrocytic activity, highlighting the importance of astrocytes in

  14. Extension Agrometeorology as the Answer to Stakeholder Realities: Response Farming and the Consequences of Climate Change

    Directory of Open Access Journals (Sweden)

    Durton Nanja

    2013-08-01

    Full Text Available Extension agrometeorology is applied in agrometeorological extension work to advice and serve farmers. In agrometeorology, response farming has been developed decades ago. Climate change complicates response farming, but does not alter it. This paper reports on new operationalization of that response farming in new educational commitments in agroclimatology. It is explained how “Science Field Shops” are an example in Indonesia. This was based on a thorough analysis of what climate change means for farmers in Asia. For Africa, we report on eying the training of agrometeorological extension trainers (“product intermediaries” in West Africa, based on a thorough analysis of what climate change means for farmers in Africa. We also compare experience with reaching farmers in South Africa and farmer communities in Zambia, as new forms of supporting response farming, all under conditions of a changing climate. The paper, for the first time, connects results from four different programs the senior author is taking part in. There is first and foremost the need for training material to make it possible for the product intermediaries to participate in training extension intermediaries. This should, particularly, bring new knowledge to farmers. With what is presently available and with new approaches, climate extension should be developed and tested with farmers in ways that improve farmer preparedness and decision making.

  15. Processes of community development and responses of ecosystems to climate change

    Energy Technology Data Exchange (ETDEWEB)

    Redente, E.F.

    1990-01-01

    Plant community development is a dynamic process that results from the responses of those organisms present at the site to a constantly fluctuating environment created by the interaction of variations in climatic, edaphic, and biotic factors imposed on the physio-geographic matrix of the site. Too often, this process of community development is studied only in relation to primary producers. Our studies are based on the premise that plant community development is closely linked to the coupling of decomposers with primary producers through direct and indirect mutualistic interactions. Therefore, plant community development is a process that can be explained only by understanding the simultaneous and closely interdependent development of primary producer and decomposer subsystem. To increase our understanding of these development relationships, our studies are investigating changes in composition, structure, and activity of soil microflora and fauna; quantity, quality, and decomposition rate of litter; and nutrient availability levels in the soil, and relating these changes to plant community development patterns within a semiarid shrubland ecosystem. 34 refs., 2 figs., 7 tabs.

  16. A Long Term View of Forest Response to Environmental Change: 25 Years of Studying Harvard Forest

    Science.gov (United States)

    Munger, J. W.; Wofsy, S. C.; Lindaas, J.; David, F.; David, O.

    2014-12-01

    Forests influence the budgets of greenhouse gases, and understanding how they will respond to environmental change is critical to accurately predicting future GHG trends. The time scale for climate change is long and forest growth is slow, thus very long measurement periods are required to observe meaningful forest response. We established an eddy flux tower within a mixed forest stand dominated by red oak and red maple at the Harvard Forest LTER site in 1989 where CO2, H2O and energy fluxes together with meteorological observations have been measured continuously. An array of plots for biometric measurements was established in 1993. Flux measurement at an adjacent hemlock stand began in 2000. Records of land use and disturbance and vegetation plot data extend back to 1907. The combined suite of measurements merges observations of instantaneous ecosystem responses to environmental forcing with details of vegetation dynamics and forest growth that represent the emergent properties relevant to long-term ecosystem change. Both the deciduous stand and hemlock stand are accumulating biomass. Each has added over 20 Mg-C ha-1 as woody biomass in trees >10cm dbh since 1990, even though the hemlock stand is older. Net carbon exchange shows enhanced uptake in early spring and late fall months in response to warmer temperatures and likely an increase in evergreen foliage at the deciduous site. Net carbon uptake efficiency at the deciduous stand has increased over time as well as indicated by peak NEE under optimum light conditions. The trend is only partly explained by variation in mean leaf area index and cannot be directly attributed to climate response. The combination of longer growing season and increased uptake efficiency yields a general trend of increasing annual NEE (Fig. 1). However, significant excursions in the trend highlight the sensitivity of forest carbon stocks. The pulse of high annual carbon uptake (peak 6 Mg-C ha-1y-1 in 2008) from 2000-2008 is only

  17. Seasonal changes in human immune responses to malaria

    DEFF Research Database (Denmark)

    Hviid, L; Theander, T G

    1993-01-01

    to apparent immune depression. However, recent data have shown that seasonal variation in cellular immune responses may occur even in the absence of detectable porositaemia. Here, Lars Hviid and Thor G. Theonder review the seasonal variation in human immune responses to malaria, and discuss its possible...

  18. From SRI to ESG: The Changing World of Responsible Investing

    Science.gov (United States)

    Caplan, Lauren; Griswold, John S.; Jarvis, William F.

    2013-01-01

    Thoughtful investment professionals continue to debate whether a portfolio's long-term performance can be enhanced by including environmental, social, and governance (ESG) considerations in the security selection process, but responsible investing is more than a passing trend. The terms socially-responsible investing, mission-related investing,…

  19. Explaining embodied cognition results.

    Science.gov (United States)

    Lakoff, George

    2012-10-01

    From the late 1950s until 1975, cognition was understood mainly as disembodied symbol manipulation in cognitive psychology, linguistics, artificial intelligence, and the nascent field of Cognitive Science. The idea of embodied cognition entered the field of Cognitive Linguistics at its beginning in 1975. Since then, cognitive linguists, working with neuroscientists, computer scientists, and experimental psychologists, have been developing a neural theory of thought and language (NTTL). Central to NTTL are the following ideas: (a) we think with our brains, that is, thought is physical and is carried out by functional neural circuitry; (b) what makes thought meaningful are the ways those neural circuits are connected to the body and characterize embodied experience; (c) so-called abstract ideas are embodied in this way as well, as is language. Experimental results in embodied cognition are seen not only as confirming NTTL but also explained via NTTL, mostly via the neural theory of conceptual metaphor. Left behind more than three decades ago is the old idea that cognition uses the abstract manipulation of disembodied symbols that are meaningless in themselves but that somehow constitute internal "representations of external reality" without serious mediation by the body and brain. This article uniquely explains the connections between embodied cognition results since that time and results from cognitive linguistics, experimental psychology, computational modeling, and neuroscience.

  20. Modeling dynamics of tundra plant communities on the Yamal Peninsula, Russia, in response to climate change and grazing pressure

    International Nuclear Information System (INIS)

    Understanding the responses of the arctic tundra biome to a changing climate requires knowledge of the complex interactions among the climate, soils and biological system. This study investigates the individual and interaction effects of climate change and reindeer grazing across a variety of climate zones and soil texture types on tundra vegetation community dynamics using an arctic vegetation model that incorporates the reindeer diet, where grazing is a function of both foliar nitrogen concentration and reindeer forage preference. We found that grazing is important, in addition to the latitudinal climate gradient, in controlling tundra plant community composition, explaining about 13% of the total variance in model simulations for all arctic tundra subzones. The decrease in biomass of lichen, deciduous shrub and graminoid plant functional types caused by grazing is potentially dampened by climate warming. Moss biomass had a nonlinear response to increased grazing intensity, and such responses were stronger when warming was present. Our results suggest that evergreen shrubs may benefit from increased grazing intensity due to their low palatability, yet a growth rate sensitivity analysis suggests that changes in nutrient uptake rates may result in different shrub responses to grazing pressure. Heavy grazing caused plant communities to shift from shrub tundra toward moss, graminoid-dominated tundra in subzones C and D when evergreen shrub growth rates were decreased in the model. The response of moss, lichen and forbs to warming varied across the different subzones. Initial vegetation responses to climate change during transient warming are different from the long term equilibrium responses due to shifts in the controlling mechanisms (nutrient limitation versus competition) within tundra plant communities.

  1. Modeling dynamics of tundra plant communities on the Yamal Peninsula, Russia, in response to climate change and grazing pressure

    Science.gov (United States)

    Yu, Q.; Epstein, H. E.; Walker, D. A.; Frost, G. V.; Forbes, B. C.

    2011-10-01

    Understanding the responses of the arctic tundra biome to a changing climate requires knowledge of the complex interactions among the climate, soils and biological system. This study investigates the individual and interaction effects of climate change and reindeer grazing across a variety of climate zones and soil texture types on tundra vegetation community dynamics using an arctic vegetation model that incorporates the reindeer diet, where grazing is a function of both foliar nitrogen concentration and reindeer forage preference. We found that grazing is important, in addition to the latitudinal climate gradient, in controlling tundra plant community composition, explaining about 13% of the total variance in model simulations for all arctic tundra subzones. The decrease in biomass of lichen, deciduous shrub and graminoid plant functional types caused by grazing is potentially dampened by climate warming. Moss biomass had a nonlinear response to increased grazing intensity, and such responses were stronger when warming was present. Our results suggest that evergreen shrubs may benefit from increased grazing intensity due to their low palatability, yet a growth rate sensitivity analysis suggests that changes in nutrient uptake rates may result in different shrub responses to grazing pressure. Heavy grazing caused plant communities to shift from shrub tundra toward moss, graminoid-dominated tundra in subzones C and D when evergreen shrub growth rates were decreased in the model. The response of moss, lichen and forbs to warming varied across the different subzones. Initial vegetation responses to climate change during transient warming are different from the long term equilibrium responses due to shifts in the controlling mechanisms (nutrient limitation versus competition) within tundra plant communities.

  2. 77 FR 76034 - National Water Program 2012 Strategy: Response to Climate Change

    Science.gov (United States)

    2012-12-26

    ... mission, the National Water Program will need to adapt to already observed and projected climatic changes... AGENCY National Water Program 2012 Strategy: Response to Climate Change AGENCY: Environmental Protection... publishing the final ``National Water Program 2012 Strategy: Response to Climate Change'' (2012...

  3. Trends in Global Vegetation Activity and Climatic Drivers Indicate a Decoupled Response to Climate Change.

    Directory of Open Access Journals (Sweden)

    Antonius G T Schut

    Full Text Available Detailed understanding of a possible decoupling between climatic drivers of plant productivity and the response of ecosystems vegetation is required. We compared trends in six NDVI metrics (1982-2010 derived from the GIMMS3g dataset with modelled biomass productivity and assessed uncertainty in trend estimates. Annual total biomass weight (TBW was calculated with the LINPAC model. Trends were determined using a simple linear regression, a Thiel-Sen medium slope and a piecewise regression (PWR with two segments. Values of NDVI metrics were related to Net Primary Production (MODIS-NPP and TBW per biome and land-use type. The simple linear and Thiel-Sen trends did not differ much whereas PWR increased the fraction of explained variation, depending on the NDVI metric considered. A positive trend in TBW indicating more favorable climatic conditions was found for 24% of pixels on land, and for 5% a negative trend. A decoupled trend, indicating positive TBW trends and monotonic negative or segmented and negative NDVI trends, was observed for 17-36% of all productive areas depending on the NDVI metric used. For only 1-2% of all pixels in productive areas, a diverging and greening trend was found despite a strong negative trend in TBW. The choice of NDVI metric used strongly affected outcomes on regional scales and differences in the fraction of explained variation in MODIS-NPP between biomes were large, and a combination of NDVI metrics is recommended for global studies. We have found an increasing difference between trends in climatic drivers and observed NDVI for large parts of the globe. Our findings suggest that future scenarios must consider impacts of constraints on plant growth such as extremes in weather and nutrient availability to predict changes in NPP and CO2 sequestration capacity.

  4. Explaining the Evolution of Poverty

    DEFF Research Database (Denmark)

    Arndt, Channing; Hussain, Azhar; Jones, Edward Samuel;

    2012-01-01

    We provide a comprehensive approach for analyzing the evolution of poverty using Mozambique as a case study. Bringing together data from disparate sources, we develop a novel “back-casting” framework that links a dynamic computable general equilibrium model to a micro-simulation poverty module....... This framework provides a new approach to explaining and decomposing the evolution of poverty, as well as to examining rigorously the coherence between poverty, economic growth, and inequality outcomes. Finally, various simple but useful and rarely-applied approaches to considering regional changes in poverty...

  5. Glacial erosion changes internal mountain structure, responses to plate tectonics

    OpenAIRE

    Trulove, Susan

    2008-01-01

    Intense glacial erosion has not only carved the surface of the highest coastal mountain range on earth, the spectacular St. Elias range in Alaska, but has elicited a structural response from deep within the mountain.

  6. European phenological response to climate change matches the warming pattern

    NARCIS (Netherlands)

    Menzel, A.; Sparks, T.; Estrella, N.; Koch, E.; Aasa, A.; Ahas, R.; Alm-Kübler, K.; Bissolli, P.; Braslavska, O.; Briede, A.; Chmielewski, F.M.; Crepinsek, Z.; Curnel, Y.; Dahl, A.; Defila, C.; Donnelly, A.; Filella, Y.; Jatczak, K.; Mage, F.; Mestre, A.; Nordli, O.; Penuelas, J.; Pirinen, P.; Remisova, V.; Scheifinger, H.; Striz, M.; Susnik, A.; Vliet, van A.J.H.; Wielgolaski, F.E.; Zach, S.; Zust, A.

    2006-01-01

    Global climate change impacts can already be tracked in many physical and biological systems; in particular, terrestrial ecosystems provide a consistent picture of observed changes. One of the preferred indicators is phenology, the science of natural recurring events, as their recorded dates provide

  7. Climate change effects on agriculture: Economic responses to biophysical shocks

    NARCIS (Netherlands)

    Nelson, G.C.; Valin, H.; Sands, R.D.; Havlik, P.; Ahammad, H.; Deryng, D.; Elliott, J.; Fujimori, S.; Hasegawa, T.; Heyhoe, E.; Kyle, P.; Lampe, von M.; Lotze-Campen, H.; Croz, d' D.M.; Meijl, van H.; Mensbrugghe, van der D.; Muller, C.; Popp, A.; Robertson, R.; Robinson, S.; Schmid, E.; Schmitz, C.; Tabeau, A.A.; Willenbockel, D.

    2014-01-01

    Agricultural production is sensitive to weather and thus directly affected by climate change. Plausible estimates of these climate change impacts require combined use of climate, crop, and economic models. Results from previous studies vary substantially due to differences in models, scenarios, and

  8. Matlab for engineers explained

    CERN Document Server

    Gustafsson, Fredrik

    2003-01-01

    This book is written for students at bachelor and master programs and has four different purposes, which split the book into four parts: 1. To teach first or early year undergraduate engineering students basic knowledge in technical computations and programming using MATLAB. The first part starts from first principles and is therefore well suited both for readers with prior exposure to MATLAB but lacking a solid foundational knowledge of the capabilities of the system and readers not having any previous experience with MATLAB. The foundational knowledge gained from these interactive guided tours of the system will hopefully be sufficient for an effective utilization of MATLAB in the engineering profession, in education and in research. 2. To explain the foundations of more advanced use of MATLAB using the facilities added the last couple of years, such as extended data structures, object orientation and advanced graphics. 3. To give an introduction to the use of MATLAB in typical undergraduate courses in elec...

  9. Does Viewing Explain Doing?

    DEFF Research Database (Denmark)

    Hald, Gert Martin; Kuyper, Lisette; Adam, Philippe C G;

    2013-01-01

    INTRODUCTION: Concerns have been voiced that the use of sexually explicit materials (SEMs) may adversely affect sexual behaviors, particularly in young people. Previous studies have generally found significant associations between SEM consumption and the sexual behaviors investigated. However, mo......, Kuyper L, Adam PCG, and de Wit JBF. Does viewing explain doing? Assessing the association between sexually explicit materials use and sexual behaviors in a large sample of Dutch adolescents and young adults. J Sex Med **;**:**-**.......INTRODUCTION: Concerns have been voiced that the use of sexually explicit materials (SEMs) may adversely affect sexual behaviors, particularly in young people. Previous studies have generally found significant associations between SEM consumption and the sexual behaviors investigated. However, most...... of these studies have focused on sexual behaviors related to sexually transmitted infections or sexual aggression and/or failed to adequately control for relevant covariates. Thus, research more thoroughly investigating the association between SEM consumption and a broader range of sexual behaviors is needed. AIMS...

  10. Explaining wartime rape.

    Science.gov (United States)

    Gottschall, Jonathan

    2004-05-01

    In the years since the first reports of mass rapes in the Yugoslavian wars of secession and the genocidal massacres in Rwanda, feminist activists and scholars, human rights organizations, journalists, and social scientists have dedicated unprecedented efforts to document, explain, and seek solutions for the phenomenon of wartime rape. While contributors to this literature agree on much, there is no consensus on causal factors. This paper provides a brief overview of the literature on wartime rape in historical and ethnographical societies and a critical analysis of the four leading explanations for its root causes: the feminist theory, the cultural pathology theory, the strategic rape theory, and the biosocial theory. The paper concludes that the biosocial theory is the only one capable of bringing all the phenomena associated with wartime rape into a single explanatory context.

  11. International Legal Mechanisms Of Responsibility For The Harm To Climate Leading To Change Of The State Territory Formation

    Directory of Open Access Journals (Sweden)

    Sergey D. Belockiy

    2014-09-01

    Full Text Available In the present article author analyzed question international legal responsibility of state’s for harm done by the climatic changes caused by the emission of greenhouse gases in the course of activity in the power sphere, leading to flooding of the state territories formation. Such mechanisms are based on a number of international legal acts, from which the documents of the system UN FCCC play a key role, including both FCCC, and the Kyoto Protocol and the decisions made within the Conference of parties. At the same time there is a number of problems, unresolved within the modern international law, namely mechanisms of such responsibility realization and proof of connection existence between emissions of greenhouse gases by this state and flooding of other state territory which in principle have to lead to the responsibility occurrence. Author explains that this moment is especially important because international law doesn't forbid emissions of greenhouse gases itself. Besides, recently perspectives of climate changes began to be considered as a threat to peace and safety, what makes it possibility of implement other then UN FCCC mechanisms. Author notes that, for example, they are considered by the UN Security Council. In the conclusion author makes a statement that at this stage of development of international law we deal with a forming mechanism of the state’s international legal responsibility for the harm done by the climate changes caused by factors, including emission of greenhouse gases in the course of activity in the power sphere.

  12. A replicated climate change field experiment reveals rapid evolutionary response in an ecologically important soil invertebrate.

    Science.gov (United States)

    Bataillon, Thomas; Galtier, Nicolas; Bernard, Aurelien; Cryer, Nicolai; Faivre, Nicolas; Santoni, Sylvain; Severac, Dany; Mikkelsen, Teis N; Larsen, Klaus S; Beier, Claus; Sørensen, Jesper G; Holmstrup, Martin; Ehlers, Bodil K

    2016-07-01

    Whether species can respond evolutionarily to current climate change is crucial for the persistence of many species. Yet, very few studies have examined genetic responses to climate change in manipulated experiments carried out in natural field conditions. We examined the evolutionary response to climate change in a common annelid worm using a controlled replicated experiment where climatic conditions were manipulated in a natural setting. Analyzing the transcribed genome of 15 local populations, we found that about 12% of the genetic polymorphisms exhibit differences in allele frequencies associated to changes in soil temperature and soil moisture. This shows an evolutionary response to realistic climate change happening over short-time scale, and calls for incorporating evolution into models predicting future response of species to climate change. It also shows that designed climate change experiments coupled with genome sequencing offer great potential to test for the occurrence (or lack) of an evolutionary response. PMID:27109012

  13. Simulated annual changes in plant functional types and their responses to climate change on the northern Tibetan Plateau

    Science.gov (United States)

    Cuo, Lan; Zhang, Yongxin; Piao, Shilong; Gao, Yanhong

    2016-06-01

    Changes in plant functional types (PFTs) have important implications for both climate and water resources. Still, little is known about whether and how PFTs have changed over the past decades on the northern Tibetan Plateau (NTP) where several of the top largest rivers in the world are originated. Also, the relative importance of atmospheric conditions vs. soil physical conditions in affecting PFTs is unknown on the NTP. In this study, we used the improved Lund-Potsdam-Jena Dynamic Global Vegetation Model to investigate PFT changes through examining the changes in foliar projective coverages (FPCs) during 1957-2009 and their responses to changes in root zone soil temperature, soil moisture, air temperature, precipitation and CO2 concentrations. The results show spatially heterogeneous changes in FPCs across the NTP during 1957-2009, with 34 % (13 %) of the region showing increasing (decreasing) trends. Dominant drivers responsible for the observed FPC changes vary with regions and vegetation types, but overall, precipitation is the major factor in determining FPC changes on the NTP with positive impacts. Soil temperature increase exhibits small but negative impacts on FPCs. Different responses of individual FPCs to regionally varying climate change result in spatially heterogeneous patterns of vegetation changes on the NTP. The implication of the study is that fresh water resources in one of the world's largest and most important headwater basins and the onset and intensity of Asian monsoon circulations could be affected because of the changes in FPCs on the NTP.

  14. Explaining Social Exclusion

    NARCIS (Netherlands)

    Gerda Jehoel-Gijsbers; Cok Vrooman

    2007-01-01

    Although social exclusion has become a key issue on the European policy agenda in recent years, both the social phenomena the term refers to and the best way to monitor these remain unclear. In response to this, we developed a conceptual model for social exclusion and a methodology for its empirical

  15. An Insurance-Led Response to Climate Change

    CERN Document Server

    Webster, Anthony J

    2015-01-01

    Climate change is widely expected to increase weather related damage and the insurance claims that result from it. This has the undesirable consequence of increasing insurance costs, in a way that is independent of a customer's contribution to the causes of climate change. This is unfortunate because insurance provides a financial mechanism that mitigates some of the consequences of climate change, allowing damage from increasingly frequent events to be repaired. We observe that the insurance industry could reclaim any increase in claims due to climate change, by increasing the insurance premiums on energy producers for example, without needing government intervention or a new tax. We argue that this insurance-led levy must acknowledge both present carbon emissions and a modern industry's carbon inheritance, that is, to recognise that fossil-fuel driven industrial growth has provided the innovations and conditions needed for modern civilisation to exist and develop. The increases in premiums would initially b...

  16. Joint science academies' statement:Global response to climate change

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ Climate change is real There will always be uncertainty in understanding a system as complex as the world's climate. However there is now strong evidence that significant global warming is occurring1.

  17. Management of the company responses to market changes

    Directory of Open Access Journals (Sweden)

    N.O. Derzhak

    2011-10-01

    Full Text Available The kinds of reactions of enterprise to changes on market, the peculiarities of choice of method of corresponding management solution and instruments for successful marketing activity are considered.

  18. Why responses to dramatic climate change are important?

    Institute of Scientific and Technical Information of China (English)

    Anders Pape Mφller

    2011-01-01

    @@ Climate change is proceeding at an unprecedented pace with global temperatures and sea-levels setting new records almost every year (IPCC, 2007).While these changes are worrisome due to effects on all biological systems and hence also on humans, even more problematic changes may be in the waiting, because not only is the climate changing, but it is also becoming more extreme.Extreme temperatures, rainfall, droughts, storms and fires are already becoming more common with severe consequences for humans, their crops and domestic animals and all wild organisms.For example, the severe heat wave in 2003 caused an excess mortality of 2,600 humans in France alone (INSERM, 2003), and primary production was suppressed across Europe (Ciais et al.2004).

  19. Fisheries management responses to climate change in the Baltic Sea

    DEFF Research Database (Denmark)

    Thøgersen, Thomas Talund; Hoff, Ayoe; Frost, Hans S.

    2015-01-01

    plan may be needed. Therefore, this paper investigates the economic impacts of managing the cod, sprat and herring stocks in the eastern Baltic Sea, given on-going climate change, which is known to affect cod recruitment negatively. It is shown that climate change may have severe biological...... scenarios in which the economic consequences of different management objectives for the fishing fleets are assessed through a dynamic multi-species and multi-fleet bio-economic assessment model that include both species interactions and climate change.......The long term management plan for cod in the eastern Baltic Sea was introduced in 2007 to ensure the full reproductive capacity of cod and an economically viable fishing industry. If these goals are to be fulfilled under changing environmental conditions, a readjustment of the current management...

  20. El Cambio Conceptual en Psicología: ¿Cómo Explicar la Novedad Cognoscitiva? Conceptual Change in Psychology of Development: ¿How to Explain Cognitive Novelty?

    Directory of Open Access Journals (Sweden)

    José Antonio Castorina

    2006-11-01

    Full Text Available Este trabajo examina críticamente la teoría del Bootstrapping, formulada por Susan Carey para explicar el cambio conceptual en la psicología del desarrollo. En primer lugar, se exponen los resultados de sus investigaciones sobre el conocimiento biológico de los niños, luego se analiza la utilización de la filosofía de la ciencia en sus estudios; a continuación se establecen las modalidades del cambio conceptual. Más tarde, se presenta centralmente la dinámica del proceso de bootstrapping para las ideas biológicas y se la extiende a la adquisición de los números enteros. Finalmente, se evalúa el alcance y el significado del bootstrapping respecto de la psicología cognitiva y la dialéctica piagetiana.The aim of this paper is to critically review the theory of Bootstrappping as stated by Susan Carey in order to explain conceptual change in psychology of development. The first section explains the results of her research on biological theories of childhood, then, the use of philosophy of science in her investigations. Next, the various forms of conceptual change are assessed. Subsequently, the paper particularly presents the dynamics of bootstrapping process for biological ideas and its extent to the acquisition of whole numbers. Finally, the importance and meaning of bootstrapping is analyzed with regard to cognitive psychology and Piagetian dialectics.

  1. Adaptive responses to environmental changes in Lake Victoria cichlids

    OpenAIRE

    Rijssel, Jacobus Cornelis van (Jacco)

    2014-01-01

    Lake Victoria cichlids show the fastest vertebrate adaptive radiation known which is why they function as a model organism to study evolution. In the past 40 years, Lake Victoria experienced severe environmental changes including the boom of the introduced, predatory Nile perch and eutrophication. Both environmental changes resulted in a decline of haplochromine cichlid species and numbers during the 1980s. However, during the 1990s and 2000s, some haplochromine species recovered. With the us...

  2. Precipitation Response to Land Cover Changes in the Netherlands

    Science.gov (United States)

    Daniels, E.; Lenderink, G.; Hutjes, R. W. A.; Holtslag, A. A.

    2015-12-01

    Precipitation has increased by 25% over the last century in the Netherlands. In this period, conversion of peat areas into grassland, expansion of urban areas, and the creation of new land in Lake Ijssel were the largest land cover changes. Both station data analysis (Daniels et al. 2014) and high-resolution (2.5 km) simulations with the atmospheric Weather Research and Forecasting (WRF) model suggest that the observed increase in precipitation is not due to these land cover changes. Instead, the change from historical (1900) to present (2000) land cover decreases precipitation in WRF (Figure). However, WRF seems to be very sensitive to changes in evapotranspiration. The creation of new land and the expansion of urban areas are similar from a moisture perspective, since they locally decrease evapotranspiration, and therefore affect the soil moisture-precipitation feedback mechanism. In our simulations, the resulting feedback is always positive, as a reduction in evapotranspiration causes a reduction of precipitation. There is a difference between urban areas and land in WRF however. Over urban areas, the planetary boundary layer (PBL) height increases more than the lifting condensation level (LCL), and the potential to trigger precipitation hereby increases. This in turn decreases the strength, but not sign, of the soil moisture-precipitation feedback. WRF is therefore unable to reproduce the observed precipitation enhancement downwind of urban areas. In all, it seems the sensitivity of WRF to changes in surface moisture might be too high and this questions the applicability of the model to investigate land cover changes. Daniels, E. E., G. Lenderink, R. W. A. Hutjes, and A. A. M. Holtslag, 2014: Spatial precipitation patterns and trends in The Netherlands during 1951-2009. International Journal of Climatology, 34, 1773-1784. Figure: Composite summer precipitation (mm) based on 19 single day cases (a), showing the decreases resulting from changing present to

  3. Responsible Climate Change Adaptation : Exploring, analysing and evaluating public and private responsibilities for urban adaptation to climate change

    NARCIS (Netherlands)

    Mees, Heleen

    2014-01-01

    Cities are vulnerable to climate change. To deal with climate change, city governments and private actors such as businesses and citizens need to adapt to its effects, such as sea level rise, storm surges, intense rainfall and heatwaves. However, adaptation planning and action is often hampered when

  4. Climate change and the importance of empowering citizens : Science teachers' beliefs about educational response in Nepal

    OpenAIRE

    Maharjan, Ramesh

    2013-01-01

    Educational response to climate change is one of the measures to prepare people to combat climate change. This thesis explores the lived experiences of secondary Science teachers from Kathmandu Valley on the perception of climate change, the way they handled climate change issues in the classroom setting, the problems and challenges they came across in climate change communication in the classrooms and the relevance of existing secondary Science curriculum in relation to climate change. The t...

  5. Agroecology: Implications for plant response to climate change

    Science.gov (United States)

    Agricultural ecosystems (agroecosystems) represent the balance between the physiological responses of plants and plant canopies and the energy exchanges. Rising temperature and increasing CO2 coupled with an increase in variability of precipitation will create a complex set of interactions on plant ...

  6. Corporate social responsibility as an agent for social change

    DEFF Research Database (Denmark)

    Justenlund, Anders; Rebelo, Sofia

    2012-01-01

    The intention of this paper is to provide a specific understanding of corporate social responsibility with a particular focus in social issues in relation to human resource development. The understanding of CSR is used to create a theoretical analytical framework that should provide researchers...

  7. A replicated climate change field experiment reveals rapid evolutionary response in an ecologically important soil invertebrate

    DEFF Research Database (Denmark)

    Bataillon, Thomas; Galtier, Nicolas; Bernard, Aurelien;

    2016-01-01

    associated to changes in soil temperature and soil moisture. This shows an evolutionaryresponse to realistic climate change happening over short-time scale, and calls for incorporating evolution into modelspredicting future response of species to climate change. It also shows that designed climate change...

  8. Explaining competitive reaction effects

    NARCIS (Netherlands)

    Leeflang, P.S.H.; Wittink, D.R.

    2001-01-01

    Changes in promotional expenditure decisions for a brand, as in other marketing decisions, should be based on the expected impact on purchase and consumption behavior as well as on the likely reactions by competitors. Purchase behavior may be predicted from estimated demand functions. Competitive re

  9. [Gigantism: a mystery explained].

    Science.gov (United States)

    Beckers, Alb

    2002-01-01

    Acromegaly was first described by Pierre Marie in 1886. Some years later, it became clear that acromegaly and gigantism share the same etiology: GH hypersecretion due to a pituitary adenoma, induces gigantism if already present during puberty, or an acromegalic if it appears only during the adulthood. During the XXth century, the disease has been well described and is now well controlled with several treatments. Recently, genetic alterations responsible for the disease have been elucidated. PMID:12371275

  10. Response and potential of agroforestry crops under global change

    Energy Technology Data Exchange (ETDEWEB)

    Calfapietra, C., E-mail: carlo.calfapietra@ibaf.cnr.i [Institute of Agro-Environmental and Forest Biology (IBAF), National Research Council (CNR), Via Salaria km 29300, 00015 Monterotondo Scalo, Roma (Italy); Gielen, B. [University of Antwerpen, Campus Drie Eiken, Department of Biology, Research Group of Plant and Vegetation Ecology, Universiteitsplein 1, B-2610 Wilrijk (Belgium); Karnosky, D. [Michigan Technological University, 1400 Townsend Drive, Houghton, MI 49931 (United States); Ceulemans, R. [University of Antwerpen, Campus Drie Eiken, Department of Biology, Research Group of Plant and Vegetation Ecology, Universiteitsplein 1, B-2610 Wilrijk (Belgium); Scarascia Mugnozza, G. [Department of Agronomy, Forestry and Land Use (DAF), Agricultural Research Council of Italy (CRA), Via del Caravita 7/a 00186 Roma (Italy)

    2010-04-15

    The use of agroforestry crops is a promising tool for reducing atmospheric carbon dioxide concentration through fossil fuel substitution. In particular, plantations characterised by high yields such as short rotation forestry (SRF) are becoming popular worldwide for biomass production and their role acknowledged in the Kyoto Protocol. While their contribution to climate change mitigation is being investigated, the impact of climate change itself on growth and productivity of these plantations needs particular attention, since their management might need to be modified accordingly. Besides the benefits deriving from the establishment of millions of hectares of these plantations, there is a risk of increased release into the atmosphere of volatile organic compounds (VOC) emitted in large amounts by most of the species commonly used. These hydrocarbons are known to play a crucial role in tropospheric ozone formation. This might represent a negative feedback, especially in regions already characterized by elevated ozone level. - Growth and management of agroforestry plantations will be influenced by climate change.

  11. Greenhouse gas emissions considered responsible for climate change: Environmental indicators

    International Nuclear Information System (INIS)

    This paper concerns the more significant environmental indicators related to the emissions of radiatively and chemically/photochemically active trace gases. Reference is made to the preliminary work of the Intergovernmental Panel on Climate Change (IPCC) and to the proposals made in the framework of the international negotiation on climate change. Aiming to contribute to the definition of a national strategy for the reduction of greenhouse gases emissions, this paper proposes a possible application of the indicators. The calculation of the indicators is based on the emission estimate performed by ENEA (Italian National Agency for Energy, New Technologies and the Environment) for the Report on the State of the Environment edited by the Italian Ministry of the Environment. Finally, the paper suggests an application of such indicators for the international negotiation, in the framework of the Italian proposal for the Convention on climate change

  12. Developing consensus in response to regulatory change: a survival strategy

    International Nuclear Information System (INIS)

    For several years now, the nuclear industry has implemented basic regulatory guides and pursued evolving incremental changes by de facto execution of US Nuclear Regulatory Commission codes or in anticipation of them. The purpose of this paper is to describe a consensus-building process recently employed by industry representatives to respond to changes to 10CFR55, Operator's Licenses and Conforming Amendment. This process resulted from the necessity for industry stakeholders to evaluate the impact of pending regulatory change. It also highlighted the need for more dialogue in the industry and the potential of expanding links with academic representatives. In addition, the paper reports participants; documentation of unnecessary regulatory constraint and vagueness of new terminology and requirements

  13. Biodiversity and global change. Adaptative responses to global change: results and prospective. IFB-GICC restitution colloquium

    International Nuclear Information System (INIS)

    Global change is the consequence of the worldwide human print on ecology. The uncontrolled use of fossil fuels, the urbanization, the intensifying of agriculture, the homogenization of life styles and cultures, the homogenization of fauna and vegetation, the commercial trades, the bio-invasions, the over-exploitation of resources and the emergence of new economic powers (China, India, Brazil..) represent an adaptative dynamics of interactions which affects the overall biosphere and the adaptative capacities and the future of all species. Biodiversity is an ecological and societal insurance against the risks and uncertainties linked with global change. The French institute of biodiversity (IFB) has created a working group in charge of a study on global change and biodiversity, in particular in terms of: speed and acceleration of processes, interaction between the different organization levels of the world of living, scale changes, and adaptative capacities. 38 projects with an interdisciplinary approach have been retained by the IFB and the Ministry of ecology and sustainable development. The conclusion of these projects were presented at this restitution colloquium and are summarized in this document. The presentations are organized in 7 sessions dealing with: global changes and adaptation mechanisms; functional responses to global changes; spatial responses to global changes; temporal responses to global changes; selective answers to global changes; available tools and ecological services; scenarios and projections. (J.S.)

  14. Climate change compromises the immune response of maize

    Science.gov (United States)

    Maize is by quantity the most important C4 cereal crop in the US; however, future climate changes are expected to increase maize susceptibility to mycotoxigenic fungal pathogens and reduce productivity. While rising atmospheric [CO2] is a driving force behind the warmer temperatures and drought, whi...

  15. Soil management challenges in response to climatic change

    Science.gov (United States)

    Agriculture has tremendous potential to help solve global food, feed, fiber, and bioenergy challenges and respond to changing climatic conditions provided we do not compromise our soil, water and air resources. This presentation will examine soil management, defined by the Soil Science Society of Am...

  16. Psychological responses to the proximity of climate change

    Science.gov (United States)

    Brügger, Adrian; Dessai, Suraje; Devine-Wright, Patrick; Morton, Thomas A.; Pidgeon, Nicholas F.

    2015-12-01

    A frequent suggestion to increase individuals' willingness to take action on climate change and to support relevant policies is to highlight its proximal consequences, that is, those that are close in space and time. But previous studies that have tested this proximizing approach have not revealed the expected positive effects on individual action and support for addressing climate change. We present three lines of psychological reasoning that provide compelling arguments as to why highlighting proximal impacts of climate change might not be as effective a way to increase individual mitigation and adaptation efforts as is often assumed. Our contextualization of the proximizing approach within established psychological research suggests that, depending on the particular theoretical perspective one takes on this issue, and on specific individual characteristics suggested by these perspectives, proximizing can bring about the intended positive effects, can have no (visible) effect or can even backfire. Thus, the effects of proximizing are much more complex than is commonly assumed. Revealing this complexity contributes to a refined theoretical understanding of the role that psychological distance plays in the context of climate change and opens up further avenues for future research and for interventions.

  17. Plant molecular stress responses face climate change. Trends in Plants

    NARCIS (Netherlands)

    Ahuja, I.; Vos, de R.C.H.; Bones, A.M.; Hall, R.D.

    2010-01-01

    Environmental stress factors such as drought, elevated temperature, salinity and rising CO2 affect plant growth and pose a growing threat to sustainable agriculture. This has become a hot issue due to concerns about the effects of climate change on plant resources, biodiversity and global food secur

  18. Biological response to climate change on a tropical mountain

    Science.gov (United States)

    Pounds, J. Alan; Fogden, Michael P. L.; Campbell, John H.

    1999-04-01

    Recent warming has caused changes in species distribution and abundance, but the extent of the effects is unclear. Here we investigate whether such changes in highland forests at Monteverde, Costa Rica, are related to the increase in air temperatures that followed a step-like warming of tropical oceans in 1976 (refs4, 5). Twenty of 50 species of anurans (frogs and toads) in a 30-km2 study area, including the locally endemic golden toad (Bufo periglenes), disappeared following synchronous population crashes in 1987 (refs 6-8). Our results indicate that these crashes probably belong to a constellation of demographic changes that have altered communities of birds, reptiles and amphibians in the area and are linked to recent warming. The changes are all associated with patterns of dry-season mist frequency, which is negatively correlated with sea surface temperatures in the equatorial Pacific and has declined dramatically since the mid-1970s. The biological and climatic patterns suggest that atmospheric warming has raised the average altitude at the base of the orographic cloud bank, as predicted by the lifting-cloud-base hypothesis,.

  19. The responses of agriculture in Europe to climate change

    DEFF Research Database (Denmark)

    Bindi, Marco; Olesen, Jørgen E

    2011-01-01

    and in the south of European Russia. The consequences on the European agricultural ecosystems are likely to vary widely depending on the cropping system being investigated (i.e. cereals vs. forage crops vs. perennial horticulture), the region and the likely climate changes. In northern Europe, increases in yield...

  20. Dynamic response of desert wetlands to abrupt climate change.

    Science.gov (United States)

    Springer, Kathleen B; Manker, Craig R; Pigati, Jeffrey S

    2015-11-24

    Desert wetlands are keystone ecosystems in arid environments and are preserved in the geologic record as groundwater discharge (GWD) deposits. GWD deposits are inherently discontinuous and stratigraphically complex, which has limited our understanding of how desert wetlands responded to past episodes of rapid climate change. Previous studies have shown that wetlands responded to climate change on glacial to interglacial timescales, but their sensitivity to short-lived climate perturbations is largely unknown. Here, we show that GWD deposits in the Las Vegas Valley (southern Nevada, United States) provide a detailed and nearly complete record of dynamic hydrologic changes during the past 35 ka (thousands of calibrated (14)C years before present), including cycles of wetland expansion and contraction that correlate tightly with climatic oscillations recorded in the Greenland ice cores. Cessation of discharge associated with rapid warming events resulted in the collapse of entire wetland systems in the Las Vegas Valley at multiple times during the late Quaternary. On average, drought-like conditions, as recorded by widespread erosion and the formation of desert soils, lasted for a few centuries. This record illustrates the vulnerability of desert wetland flora and fauna to abrupt climate change. It also shows that GWD deposits can be used to reconstruct paleohydrologic conditions at millennial to submillennial timescales and informs conservation efforts aimed at protecting these fragile ecosystems in the face of anthropogenic warming.

  1. Business responses to climate change : identifying emergent strategies

    NARCIS (Netherlands)

    A. Kolk; J. Pinkse

    2005-01-01

    In the absence of sufficient support for the Kyoto Protocol, the international policy arena on climate change is far removed from being a 'level playing field'. Companies thus face much uncertainty about the competitive effects of the Protocol and (upcoming) regulatory measures. This means that the

  2. Social media disruptive change in healthcare : responses of healthcare providers

    NARCIS (Netherlands)

    Smailhodzic, Edin; Boonstra, Albert; Langley, David

    2016-01-01

    Social media represent specific types of technologies that are end-user driven and end-users are able to drive disruptive change giving little time to organizations to react. With rapid and powerful emergence of social media communities in healthcare, this sector is faced with new and alternative av

  3. The evolution of multinationals' responses to climate change

    NARCIS (Netherlands)

    A. Kolk; J. Pinkse

    2005-01-01

    Climate change is one of the environmental issues that has increasingly attracted business attention in the course of the 1990s. While public and policy interest started already in the late 1980s, leading to a first international agreement at the Rio-conference in 1992, the main driver for corporate

  4. The History of Germany's Response to Climate Change.

    Science.gov (United States)

    Cavender, Jeannine; Jager, Jill

    1993-01-01

    Traces the history of the German climate change debate in the last 50 years and discusses the forces and events that shaped it. Examines the way in which scientists, the government, industry, nongovernmental organizations, and the media entered into and influenced the debate. (54 references) (MDH)

  5. Dynamic response of desert wetlands to abrupt climate change.

    Science.gov (United States)

    Springer, Kathleen B; Manker, Craig R; Pigati, Jeffrey S

    2015-11-24

    Desert wetlands are keystone ecosystems in arid environments and are preserved in the geologic record as groundwater discharge (GWD) deposits. GWD deposits are inherently discontinuous and stratigraphically complex, which has limited our understanding of how desert wetlands responded to past episodes of rapid climate change. Previous studies have shown that wetlands responded to climate change on glacial to interglacial timescales, but their sensitivity to short-lived climate perturbations is largely unknown. Here, we show that GWD deposits in the Las Vegas Valley (southern Nevada, United States) provide a detailed and nearly complete record of dynamic hydrologic changes during the past 35 ka (thousands of calibrated (14)C years before present), including cycles of wetland expansion and contraction that correlate tightly with climatic oscillations recorded in the Greenland ice cores. Cessation of discharge associated with rapid warming events resulted in the collapse of entire wetland systems in the Las Vegas Valley at multiple times during the late Quaternary. On average, drought-like conditions, as recorded by widespread erosion and the formation of desert soils, lasted for a few centuries. This record illustrates the vulnerability of desert wetland flora and fauna to abrupt climate change. It also shows that GWD deposits can be used to reconstruct paleohydrologic conditions at millennial to submillennial timescales and informs conservation efforts aimed at protecting these fragile ecosystems in the face of anthropogenic warming. PMID:26554007

  6. Socially Responsible Investment and Pro-social Change

    OpenAIRE

    Martha Starr

    2007-01-01

    Socially responsible investment (SRI) refers to investing in companies based on financial and social performance, where the latter includes such concerns as the environment, sweatshop labor, and animal testing. This paper argues that SRI strongly resembles pro-social behaviors and social dynamics found in experimental settings. The role of fairness-related sanctioning is emphasized, wherein companies that treat their various stakeholders “fairly” are screened into SRI portfolios, while those ...

  7. Changes in serum cytokines in response to musculoskeletal surgical trauma

    OpenAIRE

    Reikeras, Olav; Borgen, Pål; Reseland, Janne E; Lyngstadaas, Staale P

    2014-01-01

    Background Trauma induces local and subsequent systemic inflammatory reactions, and when the cytokine production is deregulated, a systemic inflammatory response syndrome with a potentially lethal outcome can occur. The understanding of the physiological mechanism of the cytokine network would be useful to better comprehend pathological conditions. Methods We analysed a panel of 30 cytokines in the serum of 20 patients operated with total hip replacement. Cytokine release was assessed postope...

  8. The scaling law of climate change and its relevance to assessing (palaeo)biological responses

    Science.gov (United States)

    Kiessling, Wolfgang; Eichenseer, Kilian

    2014-05-01

    It is often argued that current rates of climate change are unprecedented in the geological past. At the same time, the magnitudes of change were often much greater in deep time than they are in history. The most severe global warming in the Phanerozoic, with dramatic consequences for life, probably occurred across the Permian-Triassic (P-T) boundary when an increase of tropical water temperatures of 15° C has been observed to occur over a timespan 0.8 myr (Sun et al. 2012), whereas global ocean warming over the last 50 years was 0.35° C (Burrows et al. 2011). When transforming these data into rates of change the P-T rate was roughly 370 times smaller than the current rate. We argue that the smaller rates of change inferred from geological proxy records are due to a scaling effect, that is, rates of climate change generally decrease with timespan of observation. We compiled from the published literature data on measured or inferred temperature changes and the timespans over which these changes were assessed. Our compilation currently comprises 120 values and covers timespans from 20 to 107 years. A log-log plot of timespan versus rate of temperature change depicts a highly significant correlation (r2 = 0.95) of a power-law relationship with an exponent of -0.87. Warming trends show a slightly lower exponent (-0.84) than cooling trends (-0.89) but the explained variance is better for the scaling of warming trends. Importantly, the scaled warming trend across the P-T boundary is higher than the current rates of warming. Similar scaling effects are well explored for sediment accumulation rates (Sadler 1981) and evolutionary rates (Gingerich 1993). These have been interpreted as being due to breaks in sedimentation and periods of stasis or transient reversals, respectively. In case of climate change, transient reversals in general trends are the most likely explanation for the scaling relationship. Even relatively rapid intervals of warming, such as the Pleistocene

  9. Assessing land use and cover change effects on hydrological response in the river C

    Science.gov (United States)

    Nunes, A.

    2009-04-01

    Assessing the impacts of land use change, especially the role of vegetation, on hydrological response from the plot to the catchment scale has become one of the widespread issues of scientific concern,in recent decades. The continuous expansion of urban areas, the dramatic changes in land-cover and land-use patterns and the climate change which have taken place on a global scale explain this increasing interest. Although scientists have long recognized that changes in land use and land cover are important factors affecting water circulation and the spatial-temporal variations in the distribution of water resources, little is known about the quantitative relation between land use/coverage characteristics and runoff generation or processes. Therefore, a better understanding of how land-use changes impact watershed hydrological processes will become a crucial issue for the planning, management, and sustainable development of water resources. In the past decades, abandonment of marginal agricultural land has been a widespread phenomenon in Portugal, as well as in many other countries of Europe, especially in the Mediterranean countries. The abandonment of arable land typically leads to natural succession and to the development of shrub and woodland. Shrubs like Cytisus spp.usually establish in study area. A Quercus pyrenaica Willd. wood generally appears after a long time, about 3 or 4 decades. The general aim of this work is to analyse the temporal evolution of water supplies in a Côa basins (located between 41°00'' N and 40°15'' N and 7°15'' W and 6°55'' W Greenwich)and relate its behaviour with changes undergone by the plant cover and by the main climatic variables (temperatures and precipitation). To achieve this goal, dynamics on the land use and land cover were estimated after the second half of the 20th century. The hydrological response under different land uses and plant covers were monitored during 2005 and 2006, using small permanently establish bounded

  10. Phenological responses to climate change and their trait-induced differences

    Science.gov (United States)

    Ziello, Chiara; Estella, Nicole; Menzel, Annette

    2010-05-01

    On the basis of an extensive plant phenological dataset which involves phenological stations distributed all over Europe (from Spain to Russia, from the Alps to the Scandinavian Peninsula), we assess those differences in temporal trends related to Plant Functional Types (PFTs, i.e. woodiness), ecological traits (i.e. dates of flowering) and functional traits (i.e. pollination mode). We analyze differences in the sensitivity of different flowering stages to these traits. We focus on different substages such as beginning of flowering, full flowering, end of flowering because flowering seems to be so far one of the stages most affected by climate change. An increasing risk of pollinosis is one of the most likely expected consequences of climate change, and the detection of differences in responses of wind-pollinated plants with respect to other vegetation categories is important also to understand the impact of increasing temperatures on the behavior of allergenic plants. Wind-pollinated plants can be considered as representative of allergenic species because anemophilous species include those ones with the highest capability of causing allergy-related diseases in human subjects (e.g. the birch family, some cultivated and spontaneous grasses). Our main results indicate that, during the last three decades, wind-pollinated plants are advancing more than insect-pollinated ones, moreover showing a significant linear dependence of trends on phenodates. The tendency towards an earlier onset of flowering of anemophilous species could be explained due to the fact that all the considered species are angiosperms. For this plant division, anemophily is a condition derived from entomophily, and likely developed as a response to adverse or changing environmental conditions. So, it could be possible to look at them as species somehow predisposed to a more rapid adaptation process. On the other hand, this behavior could also be caused by the direct dependence on temperature of these

  11. Resistance to Change of Responding Maintained by Unsignaled Delays to Reinforcement: A Response-Bout Analysis

    Science.gov (United States)

    Podlesnik, Christopher A.; Jimenez-Gomez, Corina; Ward, Ryan D.; Shahan, Timothy A.

    2006-01-01

    Previous experiments have shown that unsignaled delayed reinforcement decreases response rates and resistance to change. However, the effects of different delays to reinforcement on underlying response structure have not been investigated in conjunction with tests of resistance to change. In the present experiment, pigeons responded on a…

  12. Business Responses to Climate Change. Identifying Emergent Strategies

    Energy Technology Data Exchange (ETDEWEB)

    Kolk, A.; Pinkse, J. [Business School, University of Amsterdam, Amsterdam (Netherlands)

    2005-07-01

    Companies face much uncertainty about the competitive effects of the recently adopted Kyoto Protocol on global climate change and the current and future regulations that may emerge from it. Companies have considerable discretion to explore different market strategies to address global warming and reduce greenhouse gas emissions. This article examines these strategic options by reviewing the market-oriented actions that are currently being taken by 136 large companies that are part of the Global 500. There are six different market strategies that companies use to address climate change and that consist of different combinations of the market components available to managers. Managers can choose between more emphasis on improvements in their business activities through innovation or employ compensatory approaches such as emissions trading. They can either act by themselves or work with other companies, NGOs, or (local) governments.

  13. Response and potential of agroforestry crops under global change.

    Science.gov (United States)

    Calfapietra, C; Gielen, B; Karnosky, D; Ceulemans, R; Scarascia Mugnozza, G

    2010-04-01

    The use of agroforestry crops is a promising tool for reducing atmospheric carbon dioxide concentration through fossil fuel substitution. In particular, plantations characterised by high yields such as short rotation forestry (SRF) are becoming popular worldwide for biomass production and their role acknowledged in the Kyoto Protocol. While their contribution to climate change mitigation is being investigated, the impact of climate change itself on growth and productivity of these plantations needs particular attention, since their management might need to be modified accordingly. Besides the benefits deriving from the establishment of millions of hectares of these plantations, there is a risk of increased release into the atmosphere of volatile organic compounds (VOC) emitted in large amounts by most of the species commonly used. These hydrocarbons are known to play a crucial role in tropospheric ozone formation. This might represent a negative feedback, especially in regions already characterized by elevated ozone level.

  14. 21st century change in ocean response to climate forcing

    CERN Document Server

    Marčelja, Stjepan

    2015-01-01

    Modeling globally averaged information on climate forcing from the land surface temperature data, the sea surface temperatures (SST) and the empirically determined relationship between the changes in SST and the turbulent diffusion of heat into the upper ocean demonstrates a consistent link. The modeling is accurate throughout the 20th century despite the different phases of the Interdecadal Pacific Oscillation (IPO) or the strong divergence between land and ocean surface warming. It only fails during the last 15 years when SST drops well below the trend. The finding reinforces the view that slower global warming over the previous 15 years is not a caused by a negative phase of the IPO or by the variations in the upper ocean (top 700 m) warming but results from a change in the ocean behavior leading to increased heat transfer into the deeper ocean.

  15. Climate change: Problems of limits and policy responses

    International Nuclear Information System (INIS)

    Present emission rates of carbon dioxide (CO2) and the other principle greenhouse gases (radiatively important gases (RIG's)) - methane, nitrous oxide, and chlorofluorocarbons - exceed the capacity of the oceanic, terrestrial, and tropospheric sinks to absorb them. Consequently, their concentrations in the troposphere are increasing and will continue to increase so long as emissions exceed sink capacities. It is assumed that an indefinitely persistent gap between emissions and sinks of RIG's implies indefinite global warming and related changes in regional climates. The high monetary and environmental costs that would be imposed by global warming are discussed along with the changes in energy policy that are needed to insure that these high costs will not be past on to future generations

  16. Corporate Response to Climate Change: What do Stakeholders Expect?

    Directory of Open Access Journals (Sweden)

    M.S.V. Prasad

    2008-09-01

    Full Text Available This paper examines different perceptions on climate change management and disclosuresfrom the viewpoint of stakeholders in Indian Corporations. The paper shows how climatechange strategies and disclosures at different organizational levels can be linked to thesocietal and competitive contexts that companies face, embedded in a stakeholder view.Companies are divided according to certain attributes - location, geographical spread,industry, degree of vertical integration and diversification, companies prioritizing particularstakeholder groups, and their climate change strategies and disclosures including internalmeasures, supply-chain measures and/or market-based measures that move beyond the supplychain are analyzed.This paper attempts to illustrate how institutional, resource-based, supply chain andstakeholder views are all important to characterize and understand corporate strategicresponses to a sustainability issue.

  17. Implications of and possible responses to climate change

    OpenAIRE

    Kahiluoto, Helena; Rötter, Reimund

    2009-01-01

    Climate change is expected to worsen food insecurity and seriously undermines rural development prospects. It makes it harder to achieve the Millenium Development Goals and ensure a sustainable future beyond 2015. Findings from the recent 4th assessment report of IPCC, Working Group II indicate that already towards 2050 with respect to food crops yield losses between 10 and 30 % can be expected as compared to current conditions in large parts of Africa, including Western, Eastern and southern...

  18. Complex response of the forest nitrogen cycle to climate change

    OpenAIRE

    Bernal, Susana; Hedin, L. O.; Likens, G. E.; Gerber, S; D. Buso

    2012-01-01

    Climate exerts a powerful influence on biological processes, but the effects of climate change on ecosystem nutrient flux and cycling are poorly resolved. Although rare, long-term records offer a unique opportunity to disentangle effects of climate from other anthropogenic influences. Here, we examine the longest and most complete record of watershed nutrient and climate dynamics available worldwide, which was collected at the Hubbard Brook Experimental Forest in the northeastern United State...

  19. 21st century change in ocean response to climate forcing

    OpenAIRE

    Marčelja, Stjepan

    2015-01-01

    Modeling globally averaged information on climate forcing from the land surface temperature data, the sea surface temperatures (SST) and the empirically determined relationship between the changes in SST and the turbulent diffusion of heat into the upper ocean demonstrates a consistent link. The modeling is accurate throughout the 20th century despite the different phases of the Interdecadal Pacific Oscillation (IPO) or the strong divergence between land and ocean surface warming. It only fai...

  20. Social capital and resilience in rural areas: responses to change

    OpenAIRE

    Beekman, G.; Heide, van der, D.; Heijman, W.J.M.; Schouten, M.A.H.

    2009-01-01

    In this paper we give an overview of the leading thoughts in current literature concerning social capital and its effects on rural resilience. Studying social resilience of rural areas is relevant in the emergence of global change. We demonstrate that social capital can either contribute to social resilience, or restrict it, depending on the nature of social capital. As the “restrictive” type of social capital generally prevails in rural areas, social resilience tends to be weaker here, than ...

  1. Watch your Workers Win. Changing Job Demands and HRM Responses

    OpenAIRE

    Haywood, Luke

    2011-01-01

    ED EPS; International audience; This paper considers how the demand for non-material aspects of jobs evolves over changing wealth levels and how firms may want to react. We first consider the importance of non-material job aspects in general before turning to two specifc human resource practices: flexible working hour arrangements and employer pension provision. In order to estimate the effect of wealth on job preferences without confounding it with the potential effect of job preferences on ...

  2. CHANGE IN BLOOD GELSOLIN CONCENTRATION IN RESPONSE TO PHYSICAL EXERCISE

    OpenAIRE

    Yu, C.-C.; Żendzian-Piotrowska, M.; Charmas, M.; Długołęcka, B.; Baranowski, M.; Górski, J.; Bucki, R.

    2013-01-01

    Plasma gelsolin (pGSN) produced by muscle is an abundant protein of extracellular fluids capable of severing actin filaments and eliminating actin from the circulation. Additionally, pGSN modulates the cellular effects of some bioactive lipids. In this study we test the hypothesis that hormonal and metabolic adaptations to exercise are associated with changes in gelsolin concentration in blood. Plasma samples were collected from twenty healthy males recruited from untrained (UT, n=10) and end...

  3. Coastal Aquifer Response to Environmental Change - Implications for Future Projections

    Science.gov (United States)

    Post, V.

    2014-12-01

    Coastal aquifers are important resources for water supply, and are increasingly stressed by population increase and the growing water demand for irrigation and other uses. Concern exists that these current pressures will be compunded by the adverse impacts of future environmental change, in particular sea-level rise. Numerous studies have investigated the effect of the expected sea-level rise durring the 21st century on the salintiy distribution in coastal groundwater systems. In many of these studies, the predicted changes due to an increase in sea level are typically seen as a departure from a steady-state situation. But many other studies have provided abundant evidence that groundwater systems in coastal areas are not in equilibrium with the present-day boundary conditions, i.e., coastline configuration and climate. This is borne out by, for example, the salinity distribution of groundwater, which does not obey the classical configuration of an intruded wedge of seawater extending inland from the coastline. This paper will argue that coastal aquifers systems are in a continuous state of transition. The relevance of future environmental change within the context of long-term trends will be discussed and exemplified by case studies of coastal aquifers in different parts of the world. It will be argued that the conceptualization of coastal groundwater systems, and in particular the connection between their onshore and offshore parts, is a major source of uncertainty in studies that aim to quantify the impact of sea-level rise on coastal groundwater resources.

  4. Simulation of microbubble response to ambient pressure changes

    DEFF Research Database (Denmark)

    Andersen, Klaus Scheldrup; Jensen, Jørgen Arendt

    2008-01-01

    The theory on microbubbles clearly indicates a relation between the ambient pressure and the acoustic behavior of the bubble. The purpose of this study was to optimize the sensitivity of ambient pressure measurements, using the subharmonic component, through microbubble response simulations....... The behaviour of two different contrast agents was investigated as a function of driving pulse and ambient overpressure, pov. Simulations of Levovist using a rectangular driving pulse show an almost linear reduction in the subharmonic component as pov is increased. For a 20 cycles driving pulse, a reduction...... is not completely linear as a function of the ambient pressure....

  5. Transcriptome Changes in Hirschfeldia incana in Response to Lead Exposure.

    Science.gov (United States)

    Auguy, Florence; Fahr, Mouna; Moulin, Patricia; El Mzibri, Mohamed; Smouni, Abdelaziz; Filali-Maltouf, Abdelkarim; Béna, Gilles; Doumas, Patrick

    2015-01-01

    Hirschfeldia incana, a pseudometallophyte belonging to the Brassicaceae family and widespread in the Mediterranean region, was selected for its ability to grow on soils contaminated by lead (Pb). The global comparison of gene expression using microarrays between a plant susceptible to Pb (Arabidopsis thaliana) and a Pb tolerant plant (H. incana) enabled the identification of a set of specific genes expressed in response to lead exposure. Three groups of genes were particularly over-represented by the Pb exposure in the biological processes categorized as photosynthesis, cell wall, and metal handling. Each of these gene groups was shown to be directly involved in tolerance or in protection mechanisms to the phytotoxicity associated with Pb. Among these genes, we demonstrated that MT2b, a metallothionein gene, was involved in lead accumulation, confirming the important role of metallothioneins in the accumulation and the distribution of Pb in leaves. On the other hand, several genes involved in biosynthesis of ABA were shown to be up-regulated in the roots and shoots of H. incana treated with Pb, suggesting that ABA-mediated signaling is a possible mechanism in response to Pb treatment in H. incana. This latest finding is an important research direction for future studies.

  6. Transcriptome changes in Hirschfeldia incana in response to lead exposure

    Directory of Open Access Journals (Sweden)

    Florence eAuguy

    2016-01-01

    Full Text Available Hirschfeldia incana, a pseudometallophyte belonging to the Brassicaceae family and widespread in the Mediterranean region, was selected for its ability to grow on soils contaminated by lead (Pb .The global comparison of gene expression using microarrays between a plant susceptible to Pb (Arabidopsis thaliana and a Pb tolerant plant (Hirschfeldia incana enabled the identification of a set of specific genes expressed in response to lead exposure. Three groups of genes were particularly over-represented by the Pb exposure in the biological processes categorized as photosynthesis, cell wall and metal handling. Each of these gene groups was shown to be directly involved in tolerance or in protection mechanisms to the phytotoxicity associated with Pb. Among these genes, we demonstrated that MT2b, a metallothionein gene, was involved in lead accumulation, confirming the important role of metallothioneins in the accumulation and the distribution of Pb in leaves. On the other hand, several genes involved in biosynthesis of ABA were shown to be up-regulated in the roots and shoots of H. incana treated with Pb, suggesting that ABA-mediated signaling is a possible mechanism in response to Pb treatment in H. incana. This latest finding is an important research direction for future studies.

  7. The greenhouse gas exchange responses of methane and nitrous oxide to forest change in Europe

    OpenAIRE

    Gundersen, P.; Christiansen, J. R.; G. Alberti; N. Brüggemann; Castaldi, S.; Gasche, R.; Kitzler, B.; L. Klemedtsson; R. Lobo-do-Vale; Moldan, F.; Rütting, T; Schleppi, P.; Weslien, P.; S. Zechmeister-Boltenstern

    2012-01-01

    Climate change and air pollution, interact with altering forest management and land-use change to produce short and long-term changes to forest in Europe. The impact of these changes on the forest greenhouse gas (GHG) balance is currently difficult to predict. To improve the mechanistic understanding of the ongoing changes, we studied the response of GHG (N2O, CH4) exchange from forest soils at twelve experimental or natural gradient forest...

  8. Response of European yews to climate change: a review

    Directory of Open Access Journals (Sweden)

    Peter Thomas

    2015-12-01

    Full Text Available Aim of study: Being the longest-lived of all European trees, capable of living significantly over 2,000 years, yew is highly likely to be negatively affected by climate change; this paper explores the changes in distribution and abundance. Main results: Yew is unlikely to migrate north due to its slow rate of invasion, its disjunct soil needs and an inability to cope with the expected rate of climate change. It will, however, retreat from the southern end of its range in Spain due to increased evapotranspiration allied to reduced rainfall. In the south, increased drought will be exacerbated by extreme drought and increased fire frequency. In drier areas at the northern edge of its range, yew will decline where growing on well-drained limestone outcrops with little shelter from the sun (increased evaporation and reduced water availability due to limited root spread.  On wetter northern sites, yew should find better climatic conditions but will be slow to invade new areas due to poorer reproduction affected by reduced pollen production, population fragmentation and limited seed movement. Overall, without our intervention, yew will survive by inertia in the short-term but eventual become extinct in most areas. Of equal concern will be the loss of old veteran individuals and associated biodiversity. Research highlights: There is an urgent need for interventionist management for both old and young trees, relieving the stress on old veteran trees, and planting and maintaining seedlings through vulnerable young age. A list of management priorities is given.Keywords: Yew; Taxus baccata; Temperature; Precipitation; Seedlings; Bioclimate envelope; Species range.

  9. Beyond a warming fingerprint: individualistic biogeographic responses to heterogeneous climate change in California

    Science.gov (United States)

    Rapacciuolo, Giovanni; Maher, Sean P; Schneider, Adam C; Hammond, Talisin T; Jabis, Meredith D; Walsh, Rachel E; Iknayan, Kelly J; Walden, Genevieve K; Oldfather, Meagan F; Ackerly, David D; Beissinger, Steven R

    2014-01-01

    Understanding recent biogeographic responses to climate change is fundamental for improving our predictions of likely future responses and guiding conservation planning at both local and global scales. Studies of observed biogeographic responses to 20th century climate change have principally examined effects related to ubiquitous increases in temperature – collectively termed a warming fingerprint. Although the importance of changes in other aspects of climate – particularly precipitation and water availability – is widely acknowledged from a theoretical standpoint and supported by paleontological evidence, we lack a practical understanding of how these changes interact with temperature to drive biogeographic responses. Further complicating matters, differences in life history and ecological attributes may lead species to respond differently to the same changes in climate. Here, we examine whether recent biogeographic patterns across California are consistent with a warming fingerprint. We describe how various components of climate have changed regionally in California during the 20th century and review empirical evidence of biogeographic responses to these changes, particularly elevational range shifts. Many responses to climate change do not appear to be consistent with a warming fingerprint, with downslope shifts in elevation being as common as upslope shifts across a number of taxa and many demographic and community responses being inconsistent with upslope shifts. We identify a number of potential direct and indirect mechanisms for these responses, including the influence of aspects of climate change other than temperature (e.g., the shifting seasonal balance of energy and water availability), differences in each taxon's sensitivity to climate change, trophic interactions, and land-use change. Finally, we highlight the need to move beyond a warming fingerprint in studies of biogeographic responses by considering a more multifaceted view of climate

  10. Biodiversity of Arctic marine ecosystems and responses to climate change

    DEFF Research Database (Denmark)

    Michel, C.; Bluhm, B.; Gallucci, V.;

    2012-01-01

    . These changes have important impacts on the chemical and biological processes that are at the root of marine food webs, influencing their structure, function and biodiversity. Here we summarise current knowledge on the biodiversity of Arctic marine ecosystems and provide an overview of fundamental factors...... that structure ecosystem biodiversity in the Arctic Ocean. We also discuss climateassociated effects on the biodiversity of Arctic marine ecosystems and discuss implications for the functioning of Arctic marine food webs. Based on the complexity and regional character of Arctic ecosystem reponses...

  11. Explaining governance outcomes

    DEFF Research Database (Denmark)

    Fawcett, Paul; Daugbjerg, Carsten

    2012-01-01

    as overarching measures of how governance outcomes vary between different governance arrangements. This provides the basis for a broader discussion of how these outcomes are conditioned by both a network’s structural characteristics and the way in which it is managed.......This article focuses on two sets of literature that have developed out of a shared concern with networks: the network governance school, which has been engaged in a set of macro-level questions about the extent to which networks are changing the nature of state–society relations; and the policy...... between vertical coordination on the state–society axis and horizontal coordination on the interest integration axis. This produces a typology of governance arrangements, which are evaluated according to the level of input and output legitimacy that they are likely to generate, two criteria that are taken...

  12. Explaining Poverty Evolution

    DEFF Research Database (Denmark)

    Arndt, Channing; Hussain, Mohammad Azhar; Jones, Edward Samuel;

    Measuring poverty remains a complex and contentious issue. This is particularly true in sub-Saharan Africa where poverty rates are higher, information bases typically weaker, and the underlying determinants of welfare relatively volatile. This paper employs recently collected data on household...... consumption in Mozambique to examine the evolution of consumption poverty with focus on the period 2002/03 to 2008/09. The paper contributes in four areas. First, the period in question was characterized by major movements in international commodity prices. Mozambique provides an illuminating case study...... of the implications of these world commodity price changes for living standards of poor people. Second, a novel ‘backcasting’ approach using a computable general equilibrium model of Mozambique, linked to a poverty module is introduced. Third, the backcasting approach is also employed to rigorously examine...

  13. Explaining the Effects of Government Spending Shocks

    OpenAIRE

    Zubairy, Sarah

    2010-01-01

    The objective of this paper is to identify and explain effects of a government spending shock. After accounting for large military events, I find that in response to a structural unanticipated government spending shock, output, hours, consumption and wages all rise, whereas investment falls on impact. I construct and estimate a dynamic general equilibrium model featuring deep habit formation and show that it successfully explains these effects. In particular, deep habits give rise to count...

  14. A Direct Manipulation Language for Explaining Algorithms

    OpenAIRE

    Scott, Jeremy; Guo, Philip J.; Davis, Randall

    2014-01-01

    Instructors typically explain algorithms in computer science by tracing their behavior, often on blackboards, sometimes with algorithm visualizations. Using blackboards can be tedious because they do not facilitate manipulation of the drawing, while visualizations often operate at the wrong level of abstraction or must be laboriously hand-coded for each algorithm. In response, we present a direct manipulation (DM) language for explaining algorithms by manipulating visualized data structures. ...

  15. Exploratory study of general practitioners' orientations to general practice and responses to change.

    OpenAIRE

    Petchey, R

    1994-01-01

    BACKGROUND. Research into general practitioners' responses to the changes in the health service has focused on the quantifiable dimensions of workload, stress, job satisfaction and mental health. AIM. This study set out to investigate general practitioners' practice orientations and responses to change. METHOD. The study was undertaken in 1992. 'Young principals' who had attended MSD Foundation regional courses were invited by letter to reflect on recent change in general practice and to give...

  16. Explaining immigrants’ moves into homeownership

    DEFF Research Database (Denmark)

    Andersen, Hans Skifter

    In the paper is examined the reasons for when and why immigrants in Greater Copenhagen move into homeownership after their 25th year based on data from the years 1990 to 2008 compared to residents with a Danish background. As for natives homeownership to a large extent is dependent on income......, employment and family situation, and actual changes, but the importance of these factors differ from Danes. Different immigrant groups have a somewhat lower propensity to move into homeownership than Danes, which only to some extent can be explained by differences in income, education and employment. Living...... in social housing and in multi-ethnic neighbourhoods reduces the probability of moving into homeownership. But there are still some unexplained reasons for lower homeownership rate among immigrants. A probable hypothesis is that immigrants are more uncertain about their future employment and income...

  17. Sustainable occupational responses to climate change through lifestyle choices.

    Science.gov (United States)

    Hocking, Clare; Kroksmark, Ulla

    2013-03-01

    Abstract Occupational therapists and occupational scientists are increasingly aware of the relationship between occupation and global climate change, with some working to raise awareness of the issues and others proposing that an occupational perspective can make a valuable contribution to understanding and addressing the issues. In this discussion paper the United Nations Global Survey on Sustainable Lifestyles ( 1 ), which reports young adults' beliefs about everyday occupations that have a substantial impact on the environment (food, housekeeping, and transportation) is introduced. The authors argue that the survey findings are a valuable resource for occupational therapists who are concerned about global climate change and work with young adults (age 18-35), providing valuable insights into their concerns and preferences in relation to sustainability. To illustrate the insights contained in the reports, findings from four countries are presented: New Zealand and Sweden, the authors' countries of origin, and the Philippines and Lebanon which have people living in New Zealand and Sweden. Application to individual and community-based interventions to promote more sustainable lifestyles is suggested, along with studies to examine the perspectives of young adults with a disability, as their concerns and sustainability preferences might differ due to the barriers that limit their participation in educational and vocational occupations.

  18. Marl Prairie Vegetation Response to 20th Century Hydrologic Change

    Science.gov (United States)

    Bernhardt, Christopher E.; Willard, Debra A.

    2007-01-01

    We conducted geochronologic and pollen analyses from sediment cores collected in solution holes within marl prairies of Big Cypress National Preserve to reconstruct vegetation patterns of the last few centuries and evaluate the stability and longevity of marl prairies within the greater Everglades ecosystem. Based on radiocarbon dating and pollen biostratigraphy, these cores contain sediments deposited during the last ~300 years and provide evidence for plant community composition before and after 20th century water management practices altered flow patterns throughout the Everglades. Pollen evidence indicates that pre-20th century vegetation at the sites consisted of sawgrass marshes in a peat-accumulating environment; these assemblages indicate moderate hydroperiods and water depths, comparable to those in modern sawgrass marshes of Everglades National Park. During the 20th century, vegetation changed to grass-dominated marl prairies, and calcitic sediments were deposited, indicating shortening of hydroperiods and occurrence of extended dry periods at the site. These data suggest that the presence of marl prairies at these sites is a 20th century phenomenon, resulting from hydrologic changes associated with water management practices.

  19. Thermospheric Neutral Density Responses to Changes in IMF Sector Polarity

    Science.gov (United States)

    Kwak, Y.; Kim, K.; Forbes, J.; Lee, S.

    2008-12-01

    The thermospheric density is important not only for satellite orbital tracking, but also in understanding the thermosphere-ionosphere coupling process as well. Thermospheric density variations are controlled by various sources such as Joule/particle heating, Lorentz force, thermal expansion, upwelling and horizontal wind circulation. These sources are directly or indirectly associated with the direction and/or strength of the interplanetary magnetic field (IMF). That is, there is an intimate relationship between IMF variation and thermospheric density variation. In order to examine how thermospheric density variations are influenced on the orientation and/or strength of the IMF, we used total mass density around 400 km, derived from the high- accuracy accelerometer on board the Challenging Minisatellite Payload (CHAMP) spacecraft, in 2003 when the IMF exhibited a well-defined sector polarity change with a ~27-day periodicity; directed toward the Sun (i.e., +Bx and -By) and away the Sun (-Bx and +By). It has been known that the IMF By in GSE coordinates makes a positive or negative IMF Bz offset in GSM coordinate. We discuss whether the thermospheric total mass density from CHAMP changes with the IMF sector polarity.

  20. Changes in Production Potential in China in Response to Climate Change from 1960 to 2010

    OpenAIRE

    Luo Liu; Xi Chen; Xinliang Xu; Yong Wang; Shuang Li; Ying Fu

    2014-01-01

    From the Global Agro-Ecological Zone (GAEZ) model, changes in the three climate factors (temperature, precipitation, and solar radiation) over the past five decades showed different trends and that production potential was impacted significantly by the geographic heterogeneity of climate change. An increase of approximately 1.58 million tons/decade in production potential correlated with climate change. Regions with increased production potential were located mainly in the Northeast China Pla...

  1. Plasticity and genetic adaptation mediate amphibian and reptile responses to climate change.

    Science.gov (United States)

    Urban, Mark C; Richardson, Jonathan L; Freidenfelds, Nicole A

    2014-01-01

    Phenotypic plasticity and genetic adaptation are predicted to mitigate some of the negative biotic consequences of climate change. Here, we evaluate evidence for plastic and evolutionary responses to climate variation in amphibians and reptiles via a literature review and meta-analysis. We included studies that either document phenotypic changes through time or space. Plasticity had a clear and ubiquitous role in promoting phenotypic changes in response to climate variation. For adaptive evolution, we found no direct evidence for evolution of amphibians or reptiles in response to climate change over time. However, we found many studies that documented adaptive responses to climate along spatial gradients. Plasticity provided a mixture of adaptive and maladaptive responses to climate change, highlighting that plasticity frequently, but not always, could ameliorate climate change. Based on our review, we advocate for more experiments that survey genetic changes through time in response to climate change. Overall, plastic and genetic variation in amphibians and reptiles could buffer some of the formidable threats from climate change, but large uncertainties remain owing to limited data.

  2. Our response to climate change requires nuclear power

    International Nuclear Information System (INIS)

    Australian politicians and environmental activists who reject nuclear power as the pivotal technology to combat climate change stand compromised before the court of international scientific opinion and informed global realism. The content of their rhetoric on nuclear matters comprises pseudo-science, innuendo and ideological prejudice communicated through the politics of fear and risk. The recent report of the United Nations Intergovernmental Panel on Climate Change (IPCC) calls for urgent major reductions in greenhouse gas emissions, without which the natural feedback mechanisms that control global temperatures might be overwhelmed. It points out that presently human activity produces around 23.6 billion tonnes of carbon dioxide per annum, about one half of which can be absorbed by soil and ocean. However this capacity is being rapidly destroyed by rising soil and ocean surface temperatures. The report points out that if global warming cannot be kept between manageable limits, it could lead to the destruction of the Great Barrier Reef and the Amazon rainforest, and lead to the forced migration of hundreds of millions of people from equatorial regions and the loss of vast tracts of land as ice caps melt and sea levels rise. For many scientists and engineers concerned with energy and environmental issues it is a matter of deep regret that, the IPCC meetings at Kyoto and Paris have not explicitly endorsed the central role, which could be played by nuclear energy in combating greenhouse gas production and climate change. The environmental benefits from switching to nuclear fuels are striking. The IPCC delegates attending Kyoto in 1997 must have known that light and air-conditioning for the modern International Convention Centre were obtained from an electricity grid supplied partly from a network of 54 nuclear power stations. The greenhouse gas emissions saved by the use of this network and the uranium fuel cycle is around 287 million tonnes of carbon dioxide per

  3. Response of neutral boundary-layers to changes of roughness

    DEFF Research Database (Denmark)

    Sempreviva, Anna Maria; Larsen, Søren Ejling; Mortensen, Niels Gylling;

    1990-01-01

    stratification, and the surface roughness is the main parameter. The analysis of wind data and two simple models, a surface layer and a planetary boundary layer (PBL) model, are described. Results from both models are discussed and compared with data analysis. Model parameters have been evaluated and the model......When air blows across a change in surface roughness, an internal boundary layer (IBL) develops within which the wind adapts to the new surface. This process is well described for short fetches, > 1 km. However, few data exist for large fetches on how the IBL grows to become a new equilibrium...... boundary layer where again the drag laws can be used to estimate the surface wind. To study this problem, data have been sampled for two years from four 30-m meteorological masts placed from 0 to 30 km inland from the North Sea coast of Jutland in Denmark. The present analysis is limited to neutral...

  4. The response of soil processes to climate change

    DEFF Research Database (Denmark)

    Emmett, B.A.; Beier, C.; Estiarte, M.;

    2004-01-01

    to drought were observed. Across the environmental gradient and below soil temperatures of 20degreesC at a depth of 5-10 cm, a mean Q(10) of 4.1 in respiration rates was observed although this varied from 2.4 to 7.0 between sites. Highest Q(10), values were observed in Spain and the UK and were therefore...... by soil moisture rather than temperature. When water was neither limiting or in excess, a Q(10) of 1.5 was observed for net N mineralization rates. These data suggest that key soil processes will be differentially affected by predicted changes in rainfall pattern and temperature and the net effect...

  5. Addressing language barriers: building response capacity for a changing nation.

    Science.gov (United States)

    Partida, Yolanda

    2007-11-01

    The absence of universally available language services is a national healthcare system failure, the burden of which is suffered by patients with limited English proficiency and their healthcare providers. Conceptualizing mandatory provision of language access as an unfair, unfunded mandate ignores massive and fundamental social changes taking place. Overcoming language barriers is essential to safe, quality health care. This paper, informed by the experience of Hablamos Juntos, a national demonstration project funded by the Robert Wood Johnson Foundation, argues that national and health industry investments are needed to develop population-based approaches supported by communication and information technology, and that these investments may prove useful to improving healthcare communication for English-speaking patients as well. PMID:17957423

  6. Explaining MRI examinations DVD

    International Nuclear Information System (INIS)

    When conducting MRI examinations, there are various things to be careful of. There is often stress related to the MRI examinations, so in order to perform an examination safely and smoothly, sufficient explanation must be given. An explanation of what to do and what not to do during an examination should be outlined in a brochure given to patients before the examination. There may be many patients who have misgivings about their MRI examinations, so to reduce their anxiousness and deepen their understanding of MRI examinations and to improve the safety and effiency of MRI examinations,; we created a DVD about MRI examinations. We gathered MRI-related safety information and instructions, and assessed the effect that the information might have on patients. We started a workgroup for a project to plan and record a video according to the Storyboard. When editing, we reviewed the length of each segment, the amount of information on screen, and the overall length of the DVD. We discussed the issue within the workgroup and had hospital approval. It was possible for us to complete it without depending on the supplier and the cost was kept to a minimum. Finally, we decided on a viewing location. We asked a hospital volunteers to see a complete DVD and we evaluated their responses by questionnaires. As the result, their understanding and anxieties related to MRI examinations were alleviated, as expected. Their anxiety seemed to be eased. Patients also seemed to have a deeper understanding of MRI examinations having seen an examination being conducted. (author)

  7. The response of Lake Tahoe to climate change

    Science.gov (United States)

    Sahoo, G.B.; Schladow, S.G.; Reuter, J.E.; Coats, R.; Dettinger, M.; Riverson, J.; Wolfe, B.; Costa-Cabral, M.

    2013-01-01

    Meteorology is the driving force for lake internal heating, cooling, mixing, and circulation. Thus continued global warming will affect the lake thermal properties, water level, internal nutrient loading, nutrient cycling, food-web characteristics, fish-habitat, aquatic ecosystem, and other important features of lake limnology. Using a 1-D numerical model - the Lake Clarity Model (LCM) - together with the down-scaled climatic data of the two emissions scenarios (B1 and A2) of the Geophysical Fluid Dynamics Laboratory (GFDL) Global Circulation Model, we found that Lake Tahoe will likely cease to mix to the bottom after about 2060 for A2 scenario, with an annual mixing depth of less than 200 m as the most common value. Deep mixing, which currently occurs on average every 3-4 years, will (under the GFDL B1 scenario) occur only four times during 2061 to 2098. When the lake fails to completely mix, the bottom waters are not replenished with dissolved oxygen and eventually dissolved oxygen at these depths will be depleted to zero. When this occurs, soluble reactive phosphorus (SRP) and ammonium-nitrogen (both biostimulatory) are released from the deep sediments and contribute approximately 51 % and 14 % of the total SRP and dissolved inorganic nitrogen load, respectively. The lake model suggests that climate change will drive the lake surface level down below the natural rim after 2085 for the GFDL A2 but not the GFDL B1 scenario. The results indicate that continued climate changes could pose serious threats to the characteristics of the Lake that are most highly valued. Future water quality planning must take these results into account.

  8. Polar ionospheric responses to solar wind IMF changes

    Directory of Open Access Journals (Sweden)

    Y. Zhang

    Full Text Available Auroral and airglow emissions over Eureka (89° CGM during the 1997-98 winter show striking variations in relation to solar wind IMF changes. The period January 19 to 22, 1998, was chosen for detailed study, as the IMF was particularly strong and variable. During most of the period, Bz was northward and polar arcs were observed. Several overpasses by DMSP satellites during the four day period provided a clear picture of the particle precipitation producing the polar arcs. The spectral character of these events indicated excitation by electrons of average energy 300 to 500 eV. Only occasionally were electrons of average energy up to ~1 keV observed and these appeared transitory from the ground optical data. It is noted that polar arcs appear after sudden changes in IMF By, suggesting IMF control over arc initiation. When By is positive there is arc motion from dawn to dusk, while By is negative the motion is consistently dusk to dawn. F-region (anti-sunward convections were monitored through the period from 630.0 nm emissions. The convection speed was low (100-150 m/s when Bz was northward but increased to 500 m/s after Bz turned southward on January 20.

    Key words: Atmospheric composition and structure (airglow and aurora - Ionosphere (particle precipitation - Magnetospheric Physics (polar cap phenomena

  9. Developmental changes in ERP responses to spatial frequencies.

    Directory of Open Access Journals (Sweden)

    Carlijn van den Boomen

    Full Text Available Social interaction starts with perception of other persons. One of the first steps in perception is processing of basic information such as spatial frequencies (SF, which represent details and global information. However, although behavioural perception of SF is well investigated, the developmental trajectory of the temporal characteristics of SF processing is not yet well understood. The speed of processing of this basic visual information is crucial, as it determines the speed and possibly accuracy of subsequent visual and social processes. The current study investigated developmental changes in the temporal characteristics of selective processing of high SF (HSF; details versus low SF (LSF; global. To this end, brain activity was measured using EEG in 108 children aged 3-15 years, while HSF or LSF grating stimuli were presented. Interest was in the temporal characteristics of brain activity related to LSF and HSF processing, specifically at early (N80 or later (P1 or N2 peaks in brain activity. Analyses revealed that from 7-8 years onwards HSF but not LSF stimuli evoked an N80 peak. In younger children, aged 3-8 years, the visual manipulation mainly affected the visual N2 peak. Selective processing of HSF versus LSF thus occurs at a rather late time-point (N2 peak in young children. Although behavioural research previously showed that 3-6 year-olds can perceive detailed information, the current results point out that selective processing of HSF versus LSF is still delayed in these children. The delayed processing in younger children could impede the use of LSF and HSF for emotional face processing. Thus, the current study is a starting point for understanding changes in basic visual processing which underlie social development.

  10. Dealing with Social Change: The Mormon Church's Response to Change in Women's Roles.

    Science.gov (United States)

    Iannaccone, Laurence R.; Miles, Carrie A.

    1990-01-01

    After two decades of resistance, the Mormon church has begun accommodating change in women's roles. Accommodation increases participation among younger and less experienced members but decreases participation among older and more experienced members, suggesting that successful churches must balance accommodation and resistance to social change.…

  11. Contrasting urban and rural heat stress responses to climate change

    Science.gov (United States)

    Fischer, E. M.; Oleson, K. W.; Lawrence, D. M.

    2012-02-01

    Hot temperatures in combination with high humidity cause human discomfort and may increase morbidity and mortality. A global climate model with an embedded urban model is used to explore the urban-rural contrast in the wet-bulb globe temperature, a heat stress index accounting for temperature and humidity. Wet-bulb globe temperatures are calculated at each model time step to resolve the heat stress diurnal cycle. The model simulates substantially higher heat stress in urban areas compared to neighbouring rural areas. Urban humidity deficit only weakly offsets the enhanced heat stress due to the large night-time urban heat island. The urban-rural contrast in heat stress is most pronounced at night and over mid-latitudes and subtropics. During heatwaves, the urban heat stress amplification is particularly pronounced. Heat stress strongly increases with doubled CO2 concentrations over both urban and rural surfaces. The tropics experience the greatest increase in number of high-heat-stress nights, despite a relatively weak ˜2°C warming. Given the lack of a distinct annual cycle and high relative humidity, the modest tropical warming leads to exceedance of the present-day record levels during more than half of the year in tropical regions, where adaptive capacity is often low. While the absolute urban and rural heat stress response to 2 × CO2 is similar, the occurrence of nights with extremely high heat stress increases more in cities than surrounding rural areas.

  12. Watershed scale impacts of bioenergy, landscape changes, and ecosystem response

    Science.gov (United States)

    Chaubey, Indrajeet; Cibin, Raj; Chiang, Li-Chi

    2013-04-01

    In recent years, high US gasoline prices and national security concerns have prompted a renewed interest in alternative fuel sources to meet increasing energy demands, particularly by the transportation sector. Food and animal feed crops, such as corn and soybean, sugarcane, residue from these crops, and cellulosic perennial crops grown specifically to produce bioenergy (e.g. switchgrass, Miscanthus, mixed grasses), and fast growing trees (e.g. hybrid poplar) are expected to provide the majority of the biofeedstock for energy production. One of the grand challenges in supplying large quantities of grain-based and lignocellulosic materials for the production of biofuels is ensuring that they are produced in environmentally sustainable and economically viable manner. Feedstock selection will vary geographically based on regional adaptability, productivity, and reliability. Changes in land use and management practices related to biofeedstock production may have potential impacts on water quantity and quality, sediments, and pesticides and nutrient losses, and these impacts may be exacerbated by climate variability and change. We have made many improvements in the currently available biophysical models (e.g. Soil and Water Assessment Tool or SWAT model) to evaluate sustainability of energy crop production. We have utilized the improved model to evaluate impacts of both annual (e.g. corn) and perennial bioenergy crops (e.g. Miscanthus and switchgrass at) on hydrology and water quality under the following plausible bioenergy crop production scenarios: (1) at highly erodible areas; (2) at agriculturally marginal areas; (3) at pasture areas; (4) crop residue (corn stover) removal; and (5) combinations of above scenarios. Overall results indicated improvement in water quality with introduction of perennial energy crops. Stream flow at the watershed outlet was reduced under energy crop production scenarios and ranged between 0.3% and 5% across scenarios. Erosion and sediment

  13. Response of winter fine particulate matter concentrations to emission and meteorology changes in North China

    Science.gov (United States)

    Gao, Meng; Carmichael, Gregory R.; Saide, Pablo E.; Lu, Zifeng; Yu, Man; Streets, David G.; Wang, Zifa

    2016-09-01

    The winter haze is a growing problem in North China, but the causes are not well understood. The chemistry version of the Weather Research and Forecasting model (WRF-Chem) was applied in North China to examine how PM2.5 concentrations change in response to changes in emissions (sulfur dioxide (SO2), black carbon (BC), organic carbon (OC), ammonia (NH3), and nitrogen oxides (NOx)), as well as meteorology (temperature, relative humidity (RH), and wind speeds) changes in winter. From 1960 to 2010, the dramatic changes in emissions lead to +260 % increases in sulfate, +320 % increases in nitrate, +300 % increases in ammonium, +160 % increases in BC, and +50 % increases in OC. The responses of PM2.5 to individual emission species indicate that the simultaneous increases in SO2, NH3, and NOx emissions dominated the increases in PM2.5 concentrations. PM2.5 shows more notable increases in response to changes in SO2 and NH3 as compared to increases in response to changes in NOx emissions. In addition, OC also accounts for a large fraction in PM2.5 changes. These results provide some implications for haze pollution control. The responses of PM2.5 concentrations to temperature increases are dominated by changes in wind fields and mixing heights. PM2.5 shows relatively smaller changes in response to temperature increases and RH decreases compared to changes in response to changes in wind speed and aerosol feedbacks. From 1960 to 2010, aerosol feedbacks have been significantly enhanced due to higher aerosol loadings. The discussions in this study indicate that dramatic changes in emissions are the main cause of increasing haze events in North China, and long-term trends in atmospheric circulations may be another important cause since PM2.5 is shown to be substantially affected by wind speed and aerosol feedbacks. More studies are necessary to get a better understanding of the aerosol-circulation interactions.

  14. Tourists’ Environmentally Responsible Behavior in Response to Climate Change and Tourist Experiences in Nature-Based Tourism

    Directory of Open Access Journals (Sweden)

    Ju Hyoung Han

    2016-07-01

    Full Text Available Nature-based tourism destinations—locations in which economic viability and environmental responsibility are sought—are sensitive to climate change and its effects on important environmental components of the tourism areas. To meet the dual roles, it is important for destination marketers and resources managers to provide quality experiences for tourists and to induce tourists’ environmentally responsible behavior in such destinations. This study documents the importance of perceptions toward climate change and tourist experiences in determining tourists’ environmentally responsible behavior while enjoying holidays at nature-based tourism destinations in Jeju Island, South Korea. Two hundred and eleven Korean and 204 Chinese tourists marked dominant tourist arrivals to the island, and responded to the survey questionnaire. Results showed that perceptions toward climate change and tourist experiences affect Korean tourists’ environmentally responsible behavior intentions, whereas tourist experiences—not perceptions toward climate change—only significantly affect Chinese tourists’ behavior intention. In a nature-based tourism context under the pressure of climate change and adverse environmental effects as consequences of tourism activities, resources managers and destination marketers need to develop environmental campaigns or informative tourist programs to formulate environmentally responsible behavior as well as to increase tourist quality experiences among domestic and international tourists.

  15. Integrating human responses to climate change into conservation vulnerability assessments and adaptation planning.

    Science.gov (United States)

    Maxwell, Sean L; Venter, Oscar; Jones, Kendall R; Watson, James E M

    2015-10-01

    The impact of climate change on biodiversity is now evident, with the direct impacts of changing temperature and rainfall patterns and increases in the magnitude and frequency of extreme events on species distribution, populations, and overall ecosystem function being increasingly publicized. Changes in the climate system are also affecting human communities, and a range of human responses across terrestrial and marine realms have been witnessed, including altered agricultural activities, shifting fishing efforts, and human migration. Failing to account for the human responses to climate change is likely to compromise climate-smart conservation efforts. Here, we use a well-established conservation planning framework to show how integrating human responses to climate change into both species- and site-based vulnerability assessments and adaptation plans is possible. By explicitly taking into account human responses, conservation practitioners will improve their evaluation of species and ecosystem vulnerability, and will be better able to deliver win-wins for human- and biodiversity-focused climate adaptation.

  16. Non-linearity dynamics in ecosystem response to climate change: Case studies and policy implications

    Science.gov (United States)

    Burkett, V.R.; Wilcox, D.A.; Stottlemyer, R.; Barrow, W.; Fagre, D.; Baron, J.; Nielsen, J.L.; Allen, C.D.; Peterson, D.L.; Ruggerone, G.; Doyle, T.

    2005-01-01

    Many biological, hydrological, and geological processes are interactively linked in ecosystems. These ecological phenomena normally vary within bounded ranges, but rapid, nonlinear changes to markedly different conditions can be triggered by even small differences if threshold values are exceeded. Intrinsic and extrinsic ecological thresholds can lead to effects that cascade among systems, precluding accurate modeling and prediction of system response to climate change. Ten case studies from North America illustrate how changes in climate cna lead to rapid, threshold-type responses within ecological communities; the case studies also highlight the role of human activities that alter the rate or direction of system response to climate change. Understanding and anticipating nonlinear dynamics are important aspects of adaptation planning since responses of biological resources to changes in the physical climate system are not necessarily proportional and sometimes, as in the case of complex ecological systems, inherently nonlinear.

  17. Advances on the Responses of Root Dynamics to Increased Atmospheric CO2 and Global Climate Change

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Plant roots dynamics responses to elevated atmospheric CO2 concentration, increased temperature and changed precipitation can be a key link between plant growth and long-term changes in soil organic matter and ecosystem carbon balance. This paper reviews some experiments and hypotheses developed in this area, which mainly include plant fine roots growth, root turnover, root respiration and other root dynamics responses to elevated CO2 and global climate change. Some recent new methods of studying root systems were also discussed and summarized. It holds herein that the assemblage of information about root turnover patterns, root respiration and other dynamic responses to elevated atmospheric CO2 and global climatic change can help to better understand and explore some new research areas. In this paper, some research challenges in the plant root responses to the elevated CO2 and other environmental factors during global climate change were also demonstrated.

  18. Ultrastructural changes of Saccharomyces cerevisiae in response to ethanol stress.

    Science.gov (United States)

    Ma, Manli; Han, Pei; Zhang, Ruimin; Li, Hao

    2013-09-01

    In the fermentative process using Saccharomyces cerevisiae to produce bioethanol, the performance of cells is often compromised by the accumulation of ethanol. However, the mechanism of how S. cerevisiae responds against ethanol stress remains elusive. In the current study, S. cerevisiae cells were cultured in YPD (yeast extract - peptone - dextrose) medium containing various concentrations of ethanol (0%, 2.5%, 5%, 7.5%, 10%, and 15% (v/v)). Compared with the control group without ethanol, the mean cell volume of S. cerevisiae decreased significantly in the presence of 7.5% and 10% ethanol after incubation for 16 h (P < 0.05), and in the presence of 15% ethanol at all 3 sampling time points (1, 8, and 16 h) (P < 0.05). The exposure of S. cerevisiae cells to ethanol also led to an increase in malonyldialdehyde content (P < 0.05) and a decrease in sulfhydryl group content (P < 0.05). Moreover, the observations through transmission electron microscopy enabled us to relate ultrastructural changes elicited by ethanol with the cellular stress physiology. Under ethanol stress, the integrity of the cell membrane was compromised. The swelling or distortion of mitochondria together with the occurrence of a single and large vacuole was correlated with the addition of ethanol. These results suggested that the cell membrane is one of the targets of ethanol, and the degeneration of mitochondria promoted the accumulation of intracellular reactive oxygen species.

  19. Response of Arctic marine microalgae to changes of salinity

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    An algal assemblage collected from the bottom of floe in the Greenland Sea was batchcultured at 1 ± 1℃ and 10 salinity gradients varied from 4.0 to 90.8 for 19 d. The growth for both the algal community and individual populations was characterized by an initial lag phase of six days followed by positive growth. Maximum growth rates were obtained as 0.19/d for the algal community and 0.32 to 0.39 d- 1 for individual populations for the whole experiment period, which mostly occurred at the lower salinities. The competition between the algal species and the evolution of the algal assemblages under the salinity changes was checked. After 14-d culture, the dominating algae in the lower salinities were centric diatoms, pennate diatoms and phytoflagellates, while ones in the higher salinities almost belonged to pennate diatoms. It is suggested that the sea ice algal community from the Greenland Sea prefer lower salinities to higher ones, and the decrease in salinity in small ranges could stimulate the growth of sea ice algae.

  20. Energy systems and climate change: Approaches to formulating responses

    International Nuclear Information System (INIS)

    A method is presented for computing the direct and indirect radiative forcings of emissions of carbon dioxide, nitrous oxide and methane and comparing them in terms of their carbon-equivalent radiative forcing potential as a common unit. Examples illustrate application of the method in comparisons of the carbon-equivalent emissions from coal-, oil- and natural gas-based electricity and combined heat and power production assuming near-, medium- and long-term perspectives. The second article provides a systematic approach to calculating the net cost of avoiding greenhouse-gas emissions by adopting individual supply- and demand-side fuel switching and energy efficiency measures instead of proceeding down business as usual energy paths. Individual measures are grouped and ranked to form scenario packages for total and average costs of avoided carbon equivalent emissions. Examples are presented for Sweden, the United States and the state of Karnataka, India. A key finding is that there appears to exist significant emission avoiding potential that can be exploited at a net economic benefit to society. This potential is insufficient, however, to stabilize atmospheric concentrations of the greenhouse gases. The suggestion that changes can be made to energy systems leading to significant levels of avoided carbon dioxide emissions at little or no cost to society has been refuted by economic theoreticians, whose writings warn that policies aimed at avoiding greenhouse gas emissions will incur exorbitant costs. A case study of the potential to use ethanol produced from sugar cane as a transportation fuel in Thailand is used to illustrate an integrated approach to evaluating components of alternative energy systems

  1. Evolutionary history of lagomorphs in response to global environmental change.

    Directory of Open Access Journals (Sweden)

    Deyan Ge

    Full Text Available Although species within Lagomorpha are derived from a common ancestor, the distribution range and body size of its two extant groups, ochotonids and leporids, are quite differentiated. It is unclear what has driven their disparate evolutionary history. In this study, we compile and update all fossil records of Lagomorpha for the first time, to trace the evolutionary processes and infer their evolutionary history using mitochondrial genes, body length and distribution of extant species. We also compare the forage selection of extant species, which offers an insight into their future prospects. The earliest lagomorphs originated in Asia and later diversified in different continents. Within ochotonids, more than 20 genera occupied the period from the early Miocene to middle Miocene, whereas most of them became extinct during the transition from the Miocene to Pliocene. The peak diversity of the leporids occurred during the Miocene to Pliocene transition, while their diversity dramatically decreased in the late Quaternary. Mantel tests identified a positive correlation between body length and phylogenetic distance of lagomorphs. The body length of extant ochotonids shows a normal distribution, while the body length of extant leporids displays a non-normal pattern. We also find that the forage selection of extant pikas features a strong preference for C(3 plants, while for the diet of leporids, more than 16% of plant species are identified as C(4 (31% species are from Poaceae. The ability of several leporid species to consume C(4 plants is likely to result in their size increase and range expansion, most notably in Lepus. Expansion of C(4 plants in the late Miocene, the so-called 'nature's green revolution', induced by global environmental change, is suggested to be one of the major 'ecological opportunities', which probably drove large-scale extinction and range contraction of ochotonids, but inversely promoted diversification and range expansion of

  2. Response-time evidence for mixed memory states in a sequential-presentation change-detection task.

    Science.gov (United States)

    Nosofsky, Robert M; Donkin, Chris

    2016-02-01

    Response-time (RT) and choice-probability data were obtained in a rapid visual sequential-presentation change-detection task in which memory set size, study-test lag, and objective change probabilities were manipulated. False "change" judgments increased dramatically with increasing lag, consistent with the idea that study items with long lags were ejected from a discrete-slots buffer. Error RTs were nearly invariant with set size and lag, consistent with the idea that the errors were produced by a stimulus-independent guessing process. The patterns of error and RT data could not be explained in terms of encoding limitations, but were consistent with the hypothesis that long retention lags produced a zero-stimulus-information state that required guessing. Formal modeling of the change-detection RT and error data pointed toward a hybrid model of visual working memory. The hybrid model assumed mixed states involving a combination of memory and guessing, but with higher memory resolution for items with shorter retention lags. The work raises new questions concerning the nature of the memory representations that are produced across the closely related tasks of change detection and visual memory search.

  3. Measuring Labour Supply Responses to Tax Changes by Use of Exogenous Tax Reforms

    DEFF Research Database (Denmark)

    Graversen, Ebbe Krogh

    1996-01-01

    -in-difference (DID) estimator and a suitable modified parametric DID estimator are used to estimate the labour supply responses and calculate labour supply elasticities with respect to marg inal tax rates and wage rates net of taxes. Finally, we simulate the effect of the fully implemented Danish 1994/1998 tax......This paper estimates average labour supply responses to tax changes for women in Denmark using the tax reform in 1987 as a natural experiment to identify the responsiveness to tax changes. Both changes in the participation rate and in worki ng hous are considered. A nonparametric difference...

  4. Issues in evaluation of ecosystem change in response to global change

    Energy Technology Data Exchange (ETDEWEB)

    Dowlatabadi, H.; Shevliakova, E.; Kandlikar, M.

    1994-12-31

    Uncertainty analysis of our integrated climate assessment model has revealed the importance of obtaining better market and non-market impacts. Improving market and non-market damage assessments has necessitated advances in the theoretical and applied dimensions of the problem. The assessment of climate change impacts on ecosystems provides a severe test for the new ideas being put forward. This paper provides a brief overview of, (i) the challenges inherent in modeling ecosystem dynamics; (ii) the problem of selecting an appropriate metric of change; and, (iii) the thorny issue of how to place a monetary value on market and non-market impacts. We focus on two central issues in estimation of impacts: (i) before climate change, are the systems being impacted (both ecological and economic) in equilibrium? and (ii) how quickly do ecological and related economic systems adapt to change? In addition, we attempt to be comprehensive in laying out the magnitude of the challenge ahead.

  5. Changes in terpene production and emission in response to climate change and eutrophication

    OpenAIRE

    Blanch Roure, Josep-Salvador

    2011-01-01

    80% of Volatile Organic Compounds (VOCs) that are emitted every year to the atmosphere come from biogenic sources (BVOCs), where many different families are included, such as isoprenoids. The production and emission of those compounds is influenced by environmental variables such as light and temperature. Those environmental variables will be affected by global change which has been predicted for the next decades. The main objective of this thesis was to study the effect of global change, ...

  6. The need to promote behaviour change at the cultural level: one factor explaining the limited impact of the MEMA kwa Vijana adolescent sexual health intervention in rural Tanzania. A process evaluation

    Directory of Open Access Journals (Sweden)

    Wight Daniel

    2012-09-01

    Full Text Available Abstract Background Few of the many behavioral sexual health interventions in Africa have been rigorously evaluated. Where biological outcomes have been measured, improvements have rarely been found. One of the most rigorous trials was of the multi-component MEMA kwa Vijana adolescent sexual health programme, which showed improvements in knowledge and reported attitudes and behaviour, but none in biological outcomes. This paper attempts to explain these outcomes by reviewing the process evaluation findings, particularly in terms of contextual factors. Methods A large-scale, primarily qualitative process evaluation based mainly on participant observation identified the principal contextual barriers and facilitators of behavioural change. Results The contextual barriers involved four interrelated socio-structural factors: culture (i.e. shared practices and systems of belief, economic circumstances, social status, and gender. At an individual level they appeared to operate through the constructs of the theories underlying MEMA kwa Vijana - Social Cognitive Theory and the Theory of Reasoned Action – but the intervention was unable to substantially modify these individual-level constructs, apart from knowledge. Conclusion The process evaluation suggests that one important reason for this failure is that the intervention did not operate sufficiently at a structural level, particularly in regard to culture. Recently most structural interventions have focused on gender or/and economics. Complementing these with a cultural approach could address the belief systems that justify and perpetuate gender and economic inequalities, as well as other barriers to behaviour change.

  7. Atmospheric response to Indian Ocean Dipole forcing: changes of Southeast China winter precipitation under global warming

    Science.gov (United States)

    Zhang, Ling; Sielmann, Frank; Fraedrich, Klaus; Zhi, Xiefei

    2016-05-01

    To investigate the relationship between autumn Indian Ocean Dipole (IOD) events and the subsequent winter precipitation in Southeast China (SEC), observed fields of monthly precipitation, sea surface temperature (SST) and atmospheric circulation are subjected to a running and a maximum correlation analysis. The results show a significant change of the relevance of IOD for the early modulation of SEC winter precipitation in the 1980s. After 1980, positive correlations suggest prolonged atmospheric responses to IOD forcing, which are linked to an abnormal moisture supply initiated in autumn and extended into the subsequent winter. Under global warming two modulating factors are relevant: (1) an increase of the static stability has been observed suppressing vertical heat and momentum transports; (2) a positive (mid-level) cloud-radiation feedback jointly with the associated latent heating (apparent moisture sink Q2) explains the prolongation of positive as well as negative SST anomalies by conserving the heating (apparent heat source Q1) in the coupled atmosphere-ocean system. During the positive IOD events in fall (after 1980) the dipole heating anomalies in the middle and lower troposphere over the tropical Indian Ocean are prolonged to winter by a positive mid-level cloud-radiative feedback with latent heat release. Subsequently, thermal adaptation leads to an anticyclonic anomaly over Eastern India overlying the anomalous cooling SST of the tropical Eastern Indian Ocean enhancing the moisture flow from the tropical Indian Ocean through the Bay of Bengal into South China, following the northwestern boundary of the anticyclonic circulation anomaly over east India, thereby favoring abundant precipitation in SEC.

  8. The importance of phylogeny to the study of phenological response to global climate change

    OpenAIRE

    Davis, Charles C.; Willis, Charles G.; Primack, Richard B.; Miller-Rushing, Abraham J.

    2010-01-01

    Climate change has resulted in major changes in the phenology—i.e. the timing of seasonal activities, such as flowering and bird migration—of some species but not others. These differential responses have been shown to result in ecological mismatches that can have negative fitness consequences. However, the ways in which climate change has shaped changes in biodiversity within and across communities are not well understood. Here, we build on our previous results that established a link betwee...

  9. Agricultural Producer Responses to Weather and Surface Water Variability: Implications for Climate Change

    OpenAIRE

    Manning, Dale T; Goemans, Chris; Maas, Alex

    2015-01-01

    Climate change is predicted to bring increased temperatures and changes in water availability across the United States. Understanding the responsiveness of irrigated agriculture to changes in available water, both supplemental, and natural, is critical to evaluating the potential impacts of climage change as well as measuring the benefit of new water supply development. Despite representing only half the value of total agricultural sales in the US, previous literature has mostly focused on dr...

  10. Responses of Terrestrial Ecosystems’ Net Primary Productivity to Future Regional Climate Change in China

    OpenAIRE

    Dongsheng Zhao; Shaohong Wu; Yunhe Yin

    2013-01-01

    The impact of regional climate change on net primary productivity (NPP) is an important aspect in the study of ecosystems' response to global climate change. China's ecosystems are very sensitive to climate change owing to the influence of the East Asian monsoon. The Lund-Potsdam-Jena Dynamic Global Vegetation Model for China (LPJ-CN), a global dynamical vegetation model developed for China's terrestrial ecosystems, was applied in this study to simulate the NPP changes affected by future clim...

  11. Prefrontal Single-Neuron Responses after Changes in Task Contingencies during Trace Eyeblink Conditioning in Rabbits.

    Science.gov (United States)

    Siegel, Jennifer J

    2016-01-01

    A number of studies indicate that the medial prefrontal cortex (mPFC) plays a role in mediating the expression of behavioral responses during tasks that require flexible changes in behavior. During trace eyeblink conditioning, evidence suggests that the mPFC provides the cerebellum with a persistent input to bridge the temporal gap between conditioned and unconditioned stimuli. Therefore, the mPFC is in a position to directly mediate the expression of trace conditioned responses. However, it is unknown whether persistent neural responses are associated with the flexible expression of behavior when task contingencies are changed during trace eyeblink conditioning. To investigate this, single-unit activity was recorded in the mPFC of rabbits during extinction and reacquisition of trace eyeblink conditioning, and during training to a different conditional stimulus. Persistent responses remained unchanged after full extinction, and also did not change during reacquisition training. During training to a different tone, however, the generalization of persistent responses to the new stimulus was associated with an animal's performance-when persistent responses generalized to the new tone, performance was high (>50% response rate). When persistent responses decreased to baseline rates, performance was poor (rate). The data suggest that persistent mPFC responses do not appear to mediate flexible changes in the expression of the original learning, but do appear to play a role in the generalization of that learning when the task is modified. PMID:27517083

  12. Morphological variation in salamanders and their potential response to climate change.

    Science.gov (United States)

    Ficetola, Gentile Francesco; Colleoni, Emiliano; Renaud, Julien; Scali, Stefano; Padoa-Schioppa, Emilio; Thuiller, Wilfried

    2016-06-01

    Despite the recognition that some species might quickly adapt to new conditions under climate change, demonstrating and predicting such a fundamental response is challenging. Morphological variations in response to climate may be caused by evolutionary changes or phenotypic plasticity, or both, but teasing apart these processes is difficult. Here, we built on the number of thoracic vertebrae (NTV) in ectothermic vertebrates, a known genetically based feature, to establish a link with body size and evaluate how climate change might affect the future morphological response of this group of species. First, we show that in old-world salamanders, NTV variation is strongly related to changes in body size. Secondly, using 22 salamander species as a case study, we found support for relationships between the spatial variation in selected bioclimatic variables and NTV for most of species. For 44% of species, precipitation and aridity were the predominant drivers of geographical variation of the NTV. Temperature features were dominant for 31% of species, while for 19% temperature and precipitation played a comparable role. This two-step analysis demonstrates that ectothermic vertebrates may evolve in response to climate change by modifying the number of thoracic vertebrae. These findings allow to develop scenarios for potential morphological evolution under future climate change and to identify areas and species in which the most marked evolutionary responses are expected. Resistance to climate change estimated from species distribution models was positively related to present-day species morphological response, suggesting that the ability of morphological evolution may play a role for species' persistence under climate change. The possibility that present-day capacity for local adaptation might help the resistance response to climate change can be integrated into analyses of the impact of global changes and should also be considered when planning management actions favouring

  13. Does an understanding of ecosystems responses to rainfall pulses improve predictions of responses of drylands to climate change?

    Science.gov (United States)

    Drylands will experience more intense and frequent droughts and floods. Ten-year field experiments manipulating the amount and variability of precipitation suggest that we cannot predict responses of drylands to climate change based on pulse experimentation. Long-term drought experiments showed no e...

  14. Changes in fatty acid branching and unsaturation of Streptomyces griseus and Brevibacterium fermentans as a response to growth temperature.

    OpenAIRE

    Suutari, M; Laakso, S

    1992-01-01

    Streptomyces griseus showed three different modes of changing fatty acids in response to temperature change. In Brevibacterium fermentans, two such responses were found. The responses involved changes in fatty acid branching, unsaturation, or chain length, depending on growth temperature range. Changes in unsaturation of branched-chain acids were characteristic at low growth temperatures.

  15. Assessing Land Management Changes and Population Dynamics in Central Burkina Faso in Response to Climate Change.

    Science.gov (United States)

    Kabore Bontogho, P. E.; Boubacar, I.; Afouda, A.; Joerg, H.

    2015-12-01

    Assessing landscape and population's dynamics at watershed level contribute to address anthropogenic aspect of climate change issue owing to the close link between LULC and climate changes. The objective of this study is to explore the dependencies of population to land management changes in Massili basin (2612 km²) located in central Burkina Faso. A set of three satellite scenes was acquired for the years 1990 (Landsat 7 ETM), 2002 (Landsat 7 ETM+) and 2013 (Landsat 8 OLI/TIRS) from the Global Land Cover Facility's (GLCF) website. Census data were provided by the National institute of statistics and demographic (INSD). The satellites images were classified using object-oriented classification method which was supported by historic maps and field data. Those were collected in order to allow for class definition, verification and accuracy assessments. Based on the developed land use maps, change analysis was carried out using post classification comparison in GIS. Finally, derived land use changes were compared with census data in order to explore links between population dynamics and the land use changes. It was found in 1990 that Massili watershed LULC was dominated by Tree/shrub savannah (69%, 1802.28 km2 ), Farm/Fallow was representing 22%, Gallery forest (4%), Settlement (3%), Barre soil (1%), Water bodies (1%). In 2002, the major landscape was Farm (54%). Tree/Shrub savannas were reduced to 36% while the Gallery Forest was decreased to1% of the basin area. The situation has also slightly changed in 2013 with an increase of the area devoted to farm/fallow and settlement at a rate of 3% and Gallery forest has increased to 4%. The changes in land use are in agreement with a notable increase in population. The analysis of census data showed that the number of inhabitants increased from 338 inhabitants per km2 in 1990 to 1150 inhabitants per km2 in 2013. As shown by statistical analysis (Kendall correlation tau=0.9), there is a close relation between both dynamics.

  16. Is Dealing with Climate Change a Corporation’s Responsibility? A Social Contract Perspective

    Science.gov (United States)

    Unsworth, Kerrie L.; Russell, Sally V.; Davis, Matthew C.

    2016-01-01

    In this paper, we argue that individuals – as members of society – play an important role in the expectations of whether or not companies are responsible for addressing environmental issues, and whether or not governments should regulate them. From this perspective of corporate social responsibility as a social contract we report the results of a survey of 1066 individuals. The aim of the survey was to assess participants’ belief in anthropogenic climate change, free-market ideology, and beliefs around who is responsible for dealing with climate change. Results showed that both climate change views and free market ideology have a strong effect on beliefs that companies are responsible for dealing with climate change and on support for regulatory policy to that end. Furthermore, we found that free market ideology is a barrier in the support of corporate regulatory policy. The implications of these findings for research, policy, and practice are discussed.

  17. Is Dealing with Climate Change a Corporation’s Responsibility? A Social Contract Perspective

    Science.gov (United States)

    Unsworth, Kerrie L.; Russell, Sally V.; Davis, Matthew C.

    2016-01-01

    In this paper, we argue that individuals – as members of society – play an important role in the expectations of whether or not companies are responsible for addressing environmental issues, and whether or not governments should regulate them. From this perspective of corporate social responsibility as a social contract we report the results of a survey of 1066 individuals. The aim of the survey was to assess participants’ belief in anthropogenic climate change, free-market ideology, and beliefs around who is responsible for dealing with climate change. Results showed that both climate change views and free market ideology have a strong effect on beliefs that companies are responsible for dealing with climate change and on support for regulatory policy to that end. Furthermore, we found that free market ideology is a barrier in the support of corporate regulatory policy. The implications of these findings for research, policy, and practice are discussed. PMID:27588009

  18. Is Dealing with Climate Change a Corporation's Responsibility? A Social Contract Perspective.

    Science.gov (United States)

    Unsworth, Kerrie L; Russell, Sally V; Davis, Matthew C

    2016-01-01

    In this paper, we argue that individuals - as members of society - play an important role in the expectations of whether or not companies are responsible for addressing environmental issues, and whether or not governments should regulate them. From this perspective of corporate social responsibility as a social contract we report the results of a survey of 1066 individuals. The aim of the survey was to assess participants' belief in anthropogenic climate change, free-market ideology, and beliefs around who is responsible for dealing with climate change. Results showed that both climate change views and free market ideology have a strong effect on beliefs that companies are responsible for dealing with climate change and on support for regulatory policy to that end. Furthermore, we found that free market ideology is a barrier in the support of corporate regulatory policy. The implications of these findings for research, policy, and practice are discussed. PMID:27588009

  19. Is Dealing with Climate Change a Corporation's Responsibility? A Social Contract Perspective.

    Science.gov (United States)

    Unsworth, Kerrie L; Russell, Sally V; Davis, Matthew C

    2016-01-01

    In this paper, we argue that individuals - as members of society - play an important role in the expectations of whether or not companies are responsible for addressing environmental issues, and whether or not governments should regulate them. From this perspective of corporate social responsibility as a social contract we report the results of a survey of 1066 individuals. The aim of the survey was to assess participants' belief in anthropogenic climate change, free-market ideology, and beliefs around who is responsible for dealing with climate change. Results showed that both climate change views and free market ideology have a strong effect on beliefs that companies are responsible for dealing with climate change and on support for regulatory policy to that end. Furthermore, we found that free market ideology is a barrier in the support of corporate regulatory policy. The implications of these findings for research, policy, and practice are discussed.

  20. Speech motor learning changes the neural response to both auditory and somatosensory signals

    Science.gov (United States)

    Ito, Takayuki; Coppola, Joshua H.; Ostry, David J.

    2016-01-01

    In the present paper, we present evidence for the idea that speech motor learning is accompanied by changes to the neural coding of both auditory and somatosensory stimuli. Participants in our experiments undergo adaptation to altered auditory feedback, an experimental model of speech motor learning which like visuo-motor adaptation in limb movement, requires that participants change their speech movements and associated somatosensory inputs to correct for systematic real-time changes to auditory feedback. We measure the sensory effects of adaptation by examining changes to auditory and somatosensory event-related responses. We find that adaptation results in progressive changes to speech acoustical outputs that serve to correct for the perturbation. We also observe changes in both auditory and somatosensory event-related responses that are correlated with the magnitude of adaptation. These results indicate that sensory change occurs in conjunction with the processes involved in speech motor adaptation. PMID:27181603

  1. Responsible investors acting on climate change. Investors acting on climate change. Climate: Investors take action

    International Nuclear Information System (INIS)

    Some investors are willing to lower the carbon emission financed by their investment, recognizing that climate change has financial impacts. At first they measure the carbon footprint of their portfolio, than initiate shareholder engagement actions at oil and gas companies, publish list of exclusion composed of the most carbon-intensive companies and ask for ex fossil fuels indices. In June 2015, Novethic launches the first actualisation of its study released on February 2015 on the mobilisation of investors on climate change over the whole 2015 year. The trend is gaining momentum since more than 200 additional investors publicly disclosed commitments to integrate climate risk into their investment and management practices. In September 2015, for its second update of the report on how investors are taking action on climate change, more than 800 entities were screened. As a key result, investor's actions gain momentum: approaches are growing in number and becoming more expert, divestments are widespread in Europe, and green investments promises are more ambitious. The last edition of November 2015 highlights and scans an exclusive panel of 960 investors worth Euro 30 trillion of assets who have made steps forward to tackle climate change. During the last 8 months, their number has almost increased twofold. This document brings together the first edition of Novethic's study and its three updates

  2. Teachers' Response to Curriculum Change: Balancing External and Internal Change Forces

    Science.gov (United States)

    Mellegård, Ingebjørg; Pettersen, Karin Dahlberg

    2016-01-01

    The present study investigates teachers' perceptions of curriculum change targeting the expanded freedom teachers were given as curriculum developers in the implementation process of the 2006 school reform in Norway. The new curriculum marks a distinct shift, moving from a content-driven to a learning outcomes-driven curriculum. Policy makers…

  3. Abundance changes and habitat availability drive species’ responses to climate change

    OpenAIRE

    Mair, L; Hill, J. K.; Fox, R; Botham , M; Brereton, T; Thomas, C. D.

    2014-01-01

    There is little consensus as to why there is so much variation in the rates at which different species’ geographic ranges expand in response to climate warming[1,2]. Here, we show for British butterfly species that the relative importance of species’ abundance trends and habitat availability vary over time. Species with high habitat availability expanded more rapidly from the 1970s to mid-1990s, when abundances were generally stable, whereas habitat availability effects were confined to the ...

  4. Importance of the glucocorticoid stress response in a changing world: theory, hypotheses and perspectives.

    Science.gov (United States)

    Angelier, Frédéric; Wingfield, John C

    2013-09-01

    In this perspective paper, we emphasize the importance that integrative mechanisms, and especially the GC (glucocorticoid) stress response, can play in the ability of vertebrates to cope with ongoing global change. The GC stress response is an essential mediator of allostasis (i.e., the responses of an organism to a perturbation) that aims at maintaining stability (homeostasis) despite changing conditions. The GC stress response is a complex mechanism that depends on several physiological components and aims at promoting immediate survival at the expense of other life-history components (e.g., reproduction) when a labile perturbation factor (LPF) occurs. Importantly, this mechanism is somewhat flexible and its degree of activation can be adjusted to the fitness costs and benefits that result from the GC stress response. Therefore, this GC stress response mediates life-history decisions and is involved in the regulation of important life-history trade-offs. By inducing abrupt and rapid changes in the regime of LPFs, we believe that global change can affect the efficiency of the GC stress response to maintain homeostasis and to appropriately regulate these trades-offs. This dysfunction may result in an important mismatch between new LPFs and the associated GC stress response and, thus, in the inability of vertebrates to cope with a changing world. In that context, it is essential to better understand how the GC stress response can be adjusted to new LPFs through micro-evolution, phenotypic plasticity and phenotypic flexibility (habituation and sensitization). This paper sets up a theoretical framework, hypotheses and new perspectives that will allow testing and better understanding how the GC stress response can help or constrain individuals, populations and species to adjust to ongoing global change.

  5. Traits underpinning desiccation resistance explain distribution patterns of terrestrial isopods.

    Science.gov (United States)

    Dias, André T C; Krab, Eveline J; Mariën, Janine; Zimmer, Martin; Cornelissen, Johannes H C; Ellers, Jacintha; Wardle, David A; Berg, Matty P

    2013-07-01

    Predicted changes in soil water availability regimes with climate and land-use change will impact the community of functionally important soil organisms, such as macro-detritivores. Identifying and quantifying the functional traits that underlie interspecific differences in desiccation resistance will enhance our ability to predict both macro-detritivore community responses to changing water regimes and the consequences of the associated species shifts for organic matter turnover. Using path analysis, we tested (1) how interspecific differences in desiccation resistance among 22 northwestern European terrestrial isopod species could be explained by three underlying traits measured under standard laboratory conditions, namely, body ventral surface area, water loss rate and fatal water loss; (2) whether these relationships were robust to contrasting experimental conditions and to the phylogenetic relatedness effects being excluded; (3) whether desiccation resistance and hypothesized underlying traits could explain species distribution patterns in relation to site water availability. Water loss rate and (secondarily) fatal water loss together explained 90% of the interspecific variation in desiccation resistance. Our path model indicated that body surface area affects desiccation resistance only indirectly via changes in water loss rate. Our results also show that soil moisture determines isopod species distributions by filtering them according to traits underpinning desiccation resistance. These findings reveal that it is possible to use functional traits measured under standard conditions to predict soil biota responses to water availability in the field over broad spatial scales. Taken together, our results demonstrate an increasing need to generate mechanistic models to predict the effect of global changes on functionally important organisms. PMID:23224790

  6. Soil erosion under climate change: simulatingthe response of temperature and rainfall changes in three UK catchments

    Science.gov (United States)

    Ciampalini, Rossano; Walker-Springett, Kate J.; Constantine, José Antonio; Hales, Tristram C.

    2015-04-01

    Soil erosion by water cost in environmental damages across the Great Britain is estimated in over £200m (2014 GBP) each year and could increase for the effect of climate change. Assessing the potential for increased climate-driven soil erosion, due to the several water processes involved (e.g., infiltration excess, return flow, direct precipitation onto saturated soil),is recognizedas a complex task. Climate change can have a positive and direct effect on soil erosionsuch the case of increasing rainfall in amount and intensity, or an indirect effect through the variation of the atmospheric CO2 level, which can improve plant productivityandwater infiltration capacity of soil reducing the likelihood of soil erosion. Changes in vegetation patterns and typologies with a different protection effect can lead also the soil system to dramatic changes in soil erosion rates, potentially amplifying or ameliorating the direct effects of climate change.Climate, vegetation and soil erosion are thus connected and several feedback effects could be accounted in the study of global change. Understanding these interactions may be a primary goal for clarifying the impact of global change on soil erosion and its consequences on related soil functions such as water and organic carbon storage support to vegetation and agricultural production. In this research, focused on three UK catchments (i.e. Conwy, 627 km2, Wales; Ehen, 225 km2, England; and Dee, 2100 km2, Scotland), we simulated soil erosionapplying SRES climatic scenarios(IPCC, 2000) for different CO2 emission levels. We modelled using Pesera "The Pan European Soil Erosion Risk Assessment" (Kirkby et al., 2004), a model for vegetation growing and soil erosion evaluation at regional scale. For each catchment,we realised a sensitivity - analysis - like test investigating different increments in temperature and rainfall, then, we compared the results of the SRES scenarios with the issues of the parametric sensitivity analysis. The

  7. TREFEX: Trend Estimation and Change Detection in the Response of MOX Gas Sensors

    Directory of Open Access Journals (Sweden)

    Marco Trincavelli

    2013-06-01

    Full Text Available Many applications of metal oxide gas sensors can benefit from reliable algorithms to detect significant changes in the sensor response. Significant changes indicate a change in the emission modality of a distant gas source and occur due to a sudden change of concentration or exposure to a different compound. As a consequence of turbulent gas transport and the relatively slow response and recovery times of metal oxide sensors, their response in open sampling configuration exhibits strong fluctuations that interfere with the changes of interest. In this paper we introduce TREFEX, a novel change point detection algorithm, especially designed for metal oxide gas sensors in an open sampling system. TREFEX models the response of MOX sensors as a piecewise exponential signal and considers the junctions between consecutive exponentials as change points. We formulate non-linear trend filtering and change point detection as a parameter-free convex optimization problem for single sensors and sensor arrays. We evaluate the performance of the TREFEX algorithm experimentally for different metal oxide sensors and several gas emission profiles. A comparison with the previously proposed GLR method shows a clearly superior performance of the TREFEX algorithm both in detection performance and in estimating the change time.

  8. Characterization and modeling of neutron induced transient response changes in Si:As IBC detectors

    International Nuclear Information System (INIS)

    The authors have conducted an analysis of the temporal response of an IBC detector in the presence of neutron generated compensating acceptor states under typical operating conditions. In this paper a model is presented which describes the observed transient response changes in the regime dominated by dielectric relaxation

  9. The Response of US College Enrollment to Unexpected Changes in Macroeconomic Activity

    Science.gov (United States)

    Ewing, Kris M.; Beckert, Kim A.; Ewing, Bradley T.

    2010-01-01

    This paper estimates the extent and magnitude of US college and university enrollment responses to unanticipated changes in macroeconomic activity. In particular, we consider the relationship between enrollment, economic growth, and inflation. A time series analysis known as a vector autoregression is estimated and impulse response functions are…

  10. Visualizing Changes in Pretest and Post-Test Student Responses with Consistency Plots

    Science.gov (United States)

    Wittmann, Michael C.; Black, Katrina E.

    2014-01-01

    Tabular presentations of student data often hide information about the switches in responses by individual students over the course of a semester. We extend unpublished work by Kanim on "escalator diagrams," which show changes in student responses from correct to incorrect (and vice versa) while representing pre- and postinstruction…

  11. Natural variation in stomatal responses to environmental changes among Arabidopsis thaliana ecotypes.

    Directory of Open Access Journals (Sweden)

    Sho Takahashi

    Full Text Available Stomata are small pores surrounded by guard cells that regulate gas exchange between plants and the atmosphere. Guard cells integrate multiple environmental signals and control the aperture width to ensure appropriate stomatal function for plant survival. Leaf temperature can be used as an indirect indicator of stomatal conductance to environmental signals. In this study, leaf thermal imaging of 374 Arabidopsis ecotypes was performed to assess their stomatal responses to changes in environmental CO2 concentrations. We identified three ecotypes, Köln (Kl-4, Gabelstein (Ga-0, and Chisdra (Chi-1, that have particularly low responsiveness to changes in CO2 concentrations. We next investigated stomatal responses to other environmental signals in these selected ecotypes, with Col-0 as the reference. The stomatal responses to light were also reduced in the three selected ecotypes when compared with Col-0. In contrast, their stomatal responses to changes in humidity were similar to those of Col-0. Of note, the responses to abscisic acid, a plant hormone involved in the adaptation of plants to reduced water availability, were not entirely consistent with the responses to humidity. This study demonstrates that the stomatal responses to CO2 and light share closely associated signaling mechanisms that are not generally correlated with humidity signaling pathways in these ecotypes. The results might reflect differences between ecotypes in intrinsic response mechanisms to environmental signals.

  12. Natural variation in stomatal responses to environmental changes among Arabidopsis thaliana ecotypes.

    Science.gov (United States)

    Takahashi, Sho; Monda, Keina; Negi, Juntaro; Konishi, Fumitaka; Ishikawa, Shinobu; Hashimoto-Sugimoto, Mimi; Goto, Nobuharu; Iba, Koh

    2015-01-01

    Stomata are small pores surrounded by guard cells that regulate gas exchange between plants and the atmosphere. Guard cells integrate multiple environmental signals and control the aperture width to ensure appropriate stomatal function for plant survival. Leaf temperature can be used as an indirect indicator of stomatal conductance to environmental signals. In this study, leaf thermal imaging of 374 Arabidopsis ecotypes was performed to assess their stomatal responses to changes in environmental CO2 concentrations. We identified three ecotypes, Köln (Kl-4), Gabelstein (Ga-0), and Chisdra (Chi-1), that have particularly low responsiveness to changes in CO2 concentrations. We next investigated stomatal responses to other environmental signals in these selected ecotypes, with Col-0 as the reference. The stomatal responses to light were also reduced in the three selected ecotypes when compared with Col-0. In contrast, their stomatal responses to changes in humidity were similar to those of Col-0. Of note, the responses to abscisic acid, a plant hormone involved in the adaptation of plants to reduced water availability, were not entirely consistent with the responses to humidity. This study demonstrates that the stomatal responses to CO2 and light share closely associated signaling mechanisms that are not generally correlated with humidity signaling pathways in these ecotypes. The results might reflect differences between ecotypes in intrinsic response mechanisms to environmental signals. PMID:25706630

  13. Elucidaton of DNA methylation changes in response to ionizng radiation induced double strand breaks

    Energy Technology Data Exchange (ETDEWEB)

    Herrlitz, Maren Linda

    2014-07-04

    Recent studies indicate that epigenetic modifications like DNA methylation are involved in the DNA damage response to ionizing radiation (IR). In this doctoral thesis DNA methylation changes after treatment with IR within one replication cycle time frame (≤ 24 hours) were investigated and a decrease in DNA methylation at short times after IR was observed. This fast decrease cannot be explained by a passive, replication-dependent mechanism due to reduced DNMT (DNA methyltransferase) expression. Rather it is conceivable that changing the enzymatic activity of enzymes may lead to changes in DNA methylation as a response to IR. In this context especially TET (ten eleven translocation) enzymes might play a role. These oxidize Methylcytosine (5mC) to Hydroxymethylcytosine (5hmC) and further to formylcytosine (5fC) and carboxylcytosine (5caC), being eventually replaced by cytosine via base excision repair (BER) mechanism. For the analysis of a TET-dependent DNA demethylation an appropriate experimental cellular system was established. Therefore, global 5mC levels, TET2 expression levels and 5hmC levels in different cell lines were investigated. An anti-correlation between 5mC levels and TET2 expression was shown for all cell lines, while 5hmC and 5mC levels were correlated only in a part of the investigated cell lines and no correlation between 5hmC and TET2 expression was observed. NIH/3T3 cells, showing no TET2 expression, were chosen for experiments in which the catalytic domain of TET2 (TET2CD-GFP) was overexpressed. Using two different techniques (immunofluorescence and ELISA-based colorimetric analysis), an increase in 5hmC abundance was demonstrated as a response to TET2CD-GFP overexpression, indicating that ectopically expressed TET2 is active. Similar results were obtained when TET2CD-GFP was overexpressed in U-2 OS cells, which have a high expression level of TET2. TET2CD-GFP overexpression also led to its accumulation in nucleoli. Whether this observation

  14. Developing Industry-Special Education's Joint Response To Changing Demographics in the Workforce. Final Project Report.

    Science.gov (United States)

    Clark, Donald M.

    This paper examines changing demographics in the American work force during the 1990s and implications for the economy, for America's ability to compete globally, and for industry and education. In response to these workplace and demographic changes, the National Association for Industry-Education Cooperation utilized the technique of networking…

  15. Developments in corporate responses to climate change within the past decade

    OpenAIRE

    Kolk, A.

    2008-01-01

    This chapter provides an overview of the research on business and climate change in the past decade as carried out by the author, with a particular focus on multinational companies. It covers a synopsis of policy developments, companies’ political and market responses to climate change, as indicates areas for future research.

  16. Maximized PUFA measurements improve insight in changes in fatty acid composition in response to temperature

    NARCIS (Netherlands)

    Dooremalen, van C.; Pel, R.; Ellers, J.

    2009-01-01

    A general mechanism underlying the response of ectotherms to environmental changes often involves changes in fatty acid composition. Theory predicts that a decrease in temperature causes an increase in unsaturation of fatty acids, with an important role for long-chain poly-unsaturated fatty acids (P

  17. Body size and activity times mediate mammalian responses to climate change.

    Science.gov (United States)

    McCain, Christy M; King, Sarah R B

    2014-06-01

    Model predictions of extinction risks from anthropogenic climate change are dire, but still overly simplistic. To reliably predict at-risk species we need to know which species are currently responding, which are not, and what traits are mediating the responses. For mammals, we have yet to identify overarching physiological, behavioral, or biogeographic traits determining species' responses to climate change, but they must exist. To date, 73 mammal species in North America and eight additional species worldwide have been assessed for responses to climate change, including local extirpations, range contractions and shifts, decreased abundance, phenological shifts, morphological or genetic changes. Only 52% of those species have responded as expected, 7% responded opposite to expectations, and the remaining 41% have not responded. Which mammals are and are not responding to climate change is mediated predominantly by body size and activity times (phylogenetic multivariate logistic regressions, P climate change than a shrew. Obligate diurnal and nocturnal mammals are more than twice as likely to respond as mammals with flexible activity times (P climate change in some analyses, whereas hibernation, heterothermy, burrowing, nesting, and study location did not influence responses. These results indicate that some mammal species can behaviorally escape climate change whereas others cannot, analogous to paleontology's climate sheltering hypothesis. Including body size and activity flexibility traits into future extinction risk forecasts should substantially improve their predictive utility for conservation and management. PMID:24449019

  18. Shoreline Response to Rapid 20th Century Sea-Level Change along the Iranian Caspian Coast

    NARCIS (Netherlands)

    Kakroodi, A.A.; Kroonenberg, S.B.; Goorabi, A.; Yamani, M.

    2013-01-01

    The Caspian Sea, the largest lake in the world, is characterized by rapid sea-level changes. This provides a real physical model of coastal response to rapid sea-level change in a period of just a few years, which might take a millennium along oceanic coasts. Between 1929 and 1995, the Caspian sea l

  19. Extrinsic and Intrinsic Responses to Environmental Change: Insights from Terrestrial Paleoecological Archives

    Science.gov (United States)

    Seddon, A. W. R.; Mackay, A. W.

    2015-12-01

    Current understanding of ecological behaviour indicates that systems can experience sudden and abrupt changes in state, driven either by a large external change in environmental conditions (extrinsically forced), or the result of a set local feedbacks and site-specific interactions (intrinsically mediated responses). Responses mediated by intrinsic processes are notoriously diffi- cult to predict, they can occur as slow environmental variables gradually erode the resilience of the system eventually resulting in threshold transitions between alternative stable states. Finding ways to identify, model and predict such complex ecosystem behavior has been identified as a priority research challenge for both ecology and paleoecology. The paleoecological record can play a role in understanding the processes behind abrupt ecological change because it enables the reconstruction of processes occurring over decadal-centennial timescales or longer. Therefore, paleoecological data can be used to identify the existence of ecological thresholds and to investigate the environmental processes that can lead to loss of resilience and abrupt transitions between alternate states. In addition, incidences of abrupt vegetation changes in the past can serve as palaeoecological model systems; analogues of abrupt dynamics which can be used to test theories surrounding ecological responses to climate change. Here, I present examples from a range of terrestrial ecosystems (Holocene environmental changes from a coastal lagoon in the Galapagos Islands; Northern European vegetation changes since the last deglaciation; the North American hemlock decline) demonstrating evidence of abrupt ecosystem change. For each system I present a set of statistical techniques tailored to distin- guish between extrinsic versus intrinsically mediated ecological responses. Examples are provided from both single sites (i.e. landscape scale) and multiple sites (regional-continental scale). These techniques provide a

  20. Surface elevation change and vegetation distribution dynamics in a subtropical coastal wetland: Implications for coastal wetland response to climate change

    Science.gov (United States)

    Rogers, Kerrylee; Saintilan, Neil; Woodroffe, Colin D.

    2014-08-01

    The response of coastal wetlands to sea-level rise is receiving global attention and observed changes in the distribution of mangrove and salt marsh are increasingly associated with global climate change, particularly sea-level and temperature rise, and potentially elevated carbon dioxide. Processes operating over smaller-spatial scales, such as rainfall variability and nutrient enrichment are also proposed as possible short-term drivers of changes in the distribution of mangrove and salt marsh. We consider the response of mangrove and salt marsh in a subtropical estuary to changes in environmental variables over a 12 year period by comparing rates of surface elevation change and vegetation distribution dynamics to hydrological and climatic variables, specifically water level and rainfall. This period of analysis captured inter-annual variability in sea level and rainfall associated with different phases of the El Niño Southern Oscillation (ENSO). We found that the mangrove and salt marsh trend of increasing elevation was primarily controlled by position within the tidal prism, in this case defined by inundation depth and distance to the tidal channel. Rainfall was not a primary driver of elevation trends in mangrove and salt marsh, but rainfall and water level variability did influence variability in elevation over the study period, though cross-correlation of these factors confounds identification of a single process driving this variability. These results highlight the scale-dependence of coastal wetland vegetation distribution dynamics; the longer-term trend of surface elevation increase and mangrove encroachment of salt marsh correlated with global sea-level trends, while short-term variability in surface elevation was related to local variability in water level and rainfall. Rates of surface elevation increase were found to lag behind rates of water level change within the Tweed River, which may facilitate further expansion of mangrove into salt marsh. This

  1. Landscape Ecological Risk Responses to Land Use Change in the Luanhe River Basin, China

    OpenAIRE

    Ying Li; Suiliang Huang

    2015-01-01

    Land use change has large effects on natural ecosystems, which is considered to be the main factor in eco-environment change. We analyzed the future characters of land use change by the CLUE-S model and explored landscape ecological risk responses to land use change by the landscape ecological risk index method. Using the Luanhe River Basin as a case study, we simulated future land use change from 2010 to 2030 under 3 scenarios (i.e., trend, high economic growth, and ecological security), and...

  2. High-time resolution conjugate SuperDARN radar observations of the dayside convection response to changes in IMF By

    Directory of Open Access Journals (Sweden)

    J. -P. Villain

    Full Text Available We present data from conjugate SuperDARN radars describing the high-latitude ionosphere's response to changes in the direction of IMF By during a period of steady IMF Bz southward and Bx positive. During this interval, the radars were operating in a special mode which gave high-time resolution data (30 s sampling period on three adjacent beams with a full scan every 3 min. The location of the radars around magnetic local noon at the time of the event allowed detailed observations of the variations in the ionospheric convection patterns close to the cusp region as IMF By varied. A significant time delay was observed in the ionospheric response to the IMF By changes between the two hemispheres. This is explained as being partially a consequence of the location of the dominant merging region on the magnetopause, which is ~8-12RE closer to the northern ionosphere than to the southern ionosphere (along the magnetic field line due to the dipole tilt of the magnetosphere and the orientation of the IMF. This interpretation supports the anti-parallel merging hypothesis and highlights the importance of the IMF Bx component in solar wind-magnetosphere coupling.Key words: Ionosphere (plasma convection - Magnetospheric physics (magnetopause, cusp, and boundary layers; solar wind - magnetosphere interactions

  3. Seasonal Changes in the Marine Production Cycles in Response to Changes in Arctic Sea Ice and Upper Ocean Circulation

    Science.gov (United States)

    Spitz, Y. H.; Ashjian, C. J.; Campbell, R. G.; Steele, M.; Zhang, J.

    2011-12-01

    Significant seasonal changes in arctic sea ice have been observed in recent years, characterized by unprecedented summer melt-back. As summer sea ice extent shrinks to record low levels, the peripheral seas of the Arctic Ocean are exposed much earlier to atmospheric surface heat flux, resulting in longer and warmer summers with more oceanic heat absorption. The changing seasonality in the arctic ice/ocean system will alter the timing, magnitude, duration, and pattern of marine production cycles by disrupting key trophic linkages and feedbacks in planktonic food webs. We are using a coupled pan-arctic Biology/Ice/Ocean Modeling and Assimilation System (BIOMAS) to investigate the changes in the patterns of seasonality in the arctic physical and biological system. Focus on specific regions of the Arctic, such as the Chukchi Sea, the Beaufort Sea and the adjacent central Arctic, reveals that changes in the timing of the spring bloom, its duration and the response of the secondary producers vary regionally. The major changes are, however, characterized by an earlier phytoplankton bloom and a slight increase of the biomass. In addition, the largest response in the secondary producers is seen in the magnitude of the microzooplankton concentration as well as in the period (early summer to late fall) over which the microzooplankton is present.

  4. Inbreeding and experience affect response to climate change by endangered woodpeckers.

    OpenAIRE

    Schiegg, Karin; Pasinelli, Gilberto; Walters, Jeffrey R.; Daniels, Susan J

    2002-01-01

    In recent decades, female red-cockaded woodpeckers (Picoides borealis) have laid eggs increasingly earlier in response to a changing climate, as has been observed in several other bird species breeding at north temperate latitudes. Within each year, females that lay earlier are more productive than females that lay later. However, inexperienced females, experienced females who change mates and inbred birds have not adjusted to the changing climate by laying earlier, and have suffered reproduc...

  5. Sexual selection predicts advancement of avian spring migration in response to climate change

    OpenAIRE

    Spottiswoode, Claire N.; Tøttrup, Anders P.; Coppack, Timothy

    2006-01-01

    Global warming has led to earlier spring arrival of migratory birds, but the extent of this advancement varies greatly among species, and it remains uncertain to what degree these changes are phenotypically plastic responses or microevolutionary adaptations to changing environmental conditions. We suggest that sexual selection could help to understand this variation, since early spring arrival of males is favoured by female choice. Climate change could weaken the strength of natural selection...

  6. The palaeolimnological record of regime shifts in lakes in response to climate change

    OpenAIRE

    Randsalu Wendrup, Linda

    2013-01-01

    Regime shifts in lake ecosystems can occur in response to both abrupt and continuous climate change, and the imprints they leave in palaeolimnological records allow us to investigate and better understand patterns and processes governing ecological changes on geological time scales. This thesis aims at investigating palaeolimnological records of regime shifts in lakes during the Holocene to explore how lake ecosystems responded to climate changes and anthropogenic activities and to identify t...

  7. Policies, Actions and Effects for China s Forestry Response to Global Climate Change

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Climate change is a great concern of various countries, the public and science community, and forest plays an important role in mitigating climate change. The paper made a comprehensive analysis regarding the policy selections of China to promote forestry response to the global climate change, and elaborated the concrete actions and achievements in this regard. Policy selections include: 1) Reinforce tree planting and afforestation, increase the forested area and enhance the capacity of carbon sequestration...

  8. Change in response time of stroke patients and controls during rehabilitation.

    Science.gov (United States)

    Korner-Bitensky, N; Mayo, N E; Kaizer, F

    1990-02-01

    In this study we investigated motor response times of stroke patients at admission to a rehabilitation hospital and again after 6 wk of hospitalization. A prospective comparative study was carried out on 164 stroke patients; 48 hospitalized patients served as controls. Mean motor response times to visual stimuli presented in the left and right visual fields and to centrally presented stimuli were studied. The principle finding was that stroke patients improved significantly in their response times from initial to final evaluation. While at initial assessment they performed significantly more slowly than controls, by final assessment the response times of the two groups did not differ. Visual hemineglect influenced change in response time differentially depending on side of lesion: right hemisphere lesion patients with neglect improved, whereas left hemisphere lesion patients with neglect actually deteriorated. The presence of depression influenced right hemisphere lesion patients' response times and change in response times but it did not have any influence for left hemisphere lesion patients. The findings that response time generally improved during rehabilitation has important implications for the treatment of individuals with brain injury. It will be important to identify therapeutic practices which will be effective in the remediation of response time for all patients. Ultimately the goal of intervening in slow response time is to improve performance of functional activities which are influenced by an individual's ability to respond to visual stimuli.

  9. Change In Minimum Temperature As A Response To Land Cover Change In South Florida

    Science.gov (United States)

    Kandel, H. P.; Melesse, A. M.

    2012-12-01

    Replacement of higher evapotranspirative surface materials such as water and vegetation cover by other materials such as buildings, roads, and pavements increases the Bowen's ratio from about 0.5-2.0 in rural to about ≈ 5.0 in urban areas resulting in higher surface and near surface atmospheric temperatures in the urban areas (Taha, 1997). This effect is intensified by low emissivity surfaces of the urban covers storing more heat energy during day time, but emitting less during night compared to the energy emitted by rural covers causing higher night time temperatures in urban centers, an effect called Urban Heat Island (UHI). South Florida has undergone tremendous land cover change from its pre-drainage vegetated and wetlands to post drainage agricultural and urban lands, especially after late 20th century. The objective of this study was to simultaneously analyze the land use/ land cover change and the rural/ urban minimum temperatures in south Florida for the period representing pre and post drainage states. The result shows urban sprawl increased from 8% at the beginning of the analysis period to about 14% at the end. Green vegetated areas, shrubs, and forests are found to be declined. The minimum temperature is found increased as maximum as 2°F in the urbanized stations, which remained constant or shows negligible increase in rural stations. The study dictates further micro level scrutiny in order to reach a conclusion on the development of UHI in south Florida. Key words: Bowen's ratio, emissivity, urban heat island

  10. Chromatin changes in response to drought, salinity, heat, and cold stresses in plants

    Directory of Open Access Journals (Sweden)

    Jong-Myong eKim

    2015-03-01

    Full Text Available Chromatin regulation is essential to regulate genes and genome activities. In plants, the alteration of histone modification and DNA methylation are coordinated with changes in the expression of stress-responsive genes to adapt to environmental changes. Several chromatin regulators have been shown to be involved in the regulation of stress-responsive gene networks under abiotic stress conditions. Specific histone modification sites and the histone modifiers that regulate key stress-responsive genes have been identified by genetic and biochemical approaches, revealing the importance of chromatin regulation in plant stress responses. Recent studies have also suggested that histone modification plays an important role in plant stress memory. In this review, we summarize recent progress on the regulation and alteration of histone modification (acetylation, methylation, phosphorylation, and SUMOylation in response to the abiotic stresses, drought, high-salinity, heat, and cold in plants.

  11. Assessing insect responses to climate change: What are we testing for? Where should we be heading?

    Directory of Open Access Journals (Sweden)

    Nigel R. Andrew

    2013-02-01

    Full Text Available To understand how researchers are tackling globally important issues, it is crucial to identify whether current research is comprehensive enough to make substantive predictions about general responses. We examined how research on climate change affecting insects is being assessed, what factors are being tested and the localities of studies, from 1703 papers published between 1985 and August 2012. Most published research (64% is generated from Europe and North America and being dedicated to core data analysis, with 29% of the studies analysed dedicated to Lepidoptera and 22% Diptera: which are well above their contribution to the currently identified insect species richness (estimated at 13% and 17% respectively. Research publications on Coleoptera fall well short of their proportional contribution (19% of publications but 39% of insect species identified, and to a lesser extent so do Hemiptera, and Hymenoptera. Species specific responses to changes in temperature by assessing distribution/range shifts or changes in abundance were the most commonly used methods of assessing the impact of climate change on insects. Research on insects and climate change to date is dominated by manuscripts assessing butterflies in Europe, insects of economic and/or environmental concern in forestry, agriculture, and model organisms. The research on understanding how insects will respond to a rapidly changing climate is still in its infancy, but the current trends of publications give a good basis for how we are attempting to assess insect responses. In particular, there is a crucial need for broader studies of ecological, behavioural, physiological and life history responses to be addressed across a greater range of geographic locations, particularly Asia, Africa and Australasia, and in areas of high human population growth and habitat modification. It is still too early in our understanding of taxa responses to climate change to know if charismatic taxa, such as

  12. Delayed Response of Lake Area Change to Climate Change in Siling Co Lake, Tibetan Plateau, from 2003 to 2013.

    Science.gov (United States)

    Yi, Guihua; Zhang, Tingbin

    2015-10-30

    The Tibetan Plateau is a key area for research on global environmental changes. During the past 50 years, the climate in the Siling Co lake area has become continuously warmer and wetter, which may have further caused the increase in Siling Co lake area. Based on the Siling Co lake area (2003 to 2013) and climate data acquired from the Xainza and Baingoin meteorological stations (covering 1966 to 2013), we analyzed the delayed responses of lake area changes to climate changes through grey relational analysis. The following results were obtained: (1) The Siling Co lake area exhibited a rapid expansion trend from 2003 to 2013. The lake area increased to 2318 km², with a growth ratio of 14.6% and an annual growth rate of 26.84 km²·year(-1); (2) The rate of air temperature increase was different in the different seasons. The rate in the cold season was about 0.41 °C per ten years and 0.32 °C in hot season. Precipitation evidently increased, with a change rate of 17.70 mm per ten years in the hot season and a slight increase with a change rate of 2.36 mm per ten years in the cold season. Pan evaporation exhibited evidently decreasing trends in both the hot and cold seasons, with rates of -33.35 and -14.84 mm per ten years, respectively; (3) An evident delayed response of lake area change to climate change is observed, with a delay time of approximately one to two years.

  13. Measuring and explaining house price developments

    NARCIS (Netherlands)

    De Vries, P.

    2010-01-01

    This study discusses ways of measuring and explaining the development of house prices. The goal of the research underpinning this dissertation was to develop a methodological framework for studying these developments. This framework relates, first, to correcting for changes in the composition of dwe

  14. Measuring and explaining house price developments

    NARCIS (Netherlands)

    De Vries, P.

    2010-01-01

    This study discusses ways of measuring and explaining the development of house prices. The goal of the research underpinning this dissertation was to develop a methodological framework for studying these developments. This framework relates, first, to correcting for changes in the composition of swe

  15. Rapid genetic divergence in response to 15 years of simulated climate change.

    Science.gov (United States)

    Ravenscroft, Catherine H; Whitlock, Raj; Fridley, Jason D

    2015-11-01

    Genetic diversity may play an important role in allowing individual species to resist climate change, by permitting evolutionary responses. Our understanding of the potential for such responses to climate change remains limited, and very few experimental tests have been carried out within intact ecosystems. Here, we use amplified fragment length polymorphism (AFLP) data to assess genetic divergence and test for signatures of evolutionary change driven by long-term simulated climate change applied to natural grassland at Buxton Climate Change Impacts Laboratory (BCCIL). Experimental climate treatments were applied to grassland plots for 15 years using a replicated and spatially blocked design and included warming, drought and precipitation treatments. We detected significant genetic differentiation between climate change treatments and control plots in two coexisting perennial plant study species (Festuca ovina and Plantago lanceolata). Outlier analyses revealed a consistent signature of selection associated with experimental climate treatments at individual AFLP loci in P. lanceolata, but not in F. ovina. Average background differentiation at putatively neutral AFLP loci was close to zero, and genomewide genetic structure was associated neither with species abundance changes (demography) nor with plant community-level responses to long-term climate treatments. Our results demonstrate genetic divergence in response to a suite of climatic environments in reproductively mature populations of two perennial plant species and are consistent with an evolutionary response to climatic selection in P. lanceolata. These genetic changes have occurred in parallel with impacts on plant community structure and may have contributed to the persistence of individual species through 15 years of simulated climate change at BCCIL. PMID:26311135

  16. Responses to climate and economic risks and opportunities across national and ecological boundaries: changing household strategies on the Mongolian plateau

    International Nuclear Information System (INIS)

    Climate changes on the Mongolian Plateau are creating new challenges for the households and communities of the region. Much of the existing research on household choices in response to climate variability and change focuses on environmental risks and stresses. In contrast, our analysis highlights the importance of taking into account environmental and economic opportunities in explaining household adaptation choices. We surveyed over 750 households arrayed along an ecological gradient and matched across the national border in Mongolia and the Inner Mongolia Autonomous Region, China, asking what changes in livelihoods strategies households made over the last ten years, and analyzed these choices in two broad categories of options: diversification and livestock management. We combined these data with remotely sensed information about vegetation growth and self-reported exposure to price fluctuations. Our statistical results showed that households experiencing lower ecological and economic variability, higher average levels of vegetation growth, and with greater levels of material wealth, were often those that undertook more actions to improve their conditions in the face of variability. The findings have implications both for how interventions aimed at supporting ongoing choices might be targeted and for theory construction related to social adaptation. (letter)

  17. Responses to climate and economic risks and opportunities across national and ecological boundaries: changing household strategies on the Mongolian plateau.

    Science.gov (United States)

    Brown, Daniel G; Agrawal, Arun; Sass, Daniel A; Wang, Jun; Hua, Jin; Xie, Yichun

    2013-01-01

    Climate changes on the Mongolian Plateau are creating new challenges for the households and communities of the region. Much of the existing research on household choices in response to climate variability and change focuses on environmental risks and stresses. In contrast, our analysis highlights the importance of taking into account environmental and economic opportunities in explaining household adaptation choices. We surveyed over 750 households arrayed along an ecological gradient and matched across the national border in Mongolia and the Inner Mongolia Autonomous Region, China, asking what changes in livelihoods strategies households made over the last ten years, and analyzed these choices in two broad categories of options: diversification and livestock management. We combined these data with remotely sensed information about vegetation growth and self-reported exposure to price fluctuations. Our statistical results showed that households experiencing lower ecological and economic variability, higher average levels of vegetation growth, and with greater levels of material wealth, were often those that undertook more actions to improve their conditions in the face of variability. The findings have implications both for how interventions aimed at supporting ongoing choices might be targeted and for theory construction related to social adaptation.

  18. Responses to climate and economic risks and opportunities across national and ecological boundaries: changing household strategies on the Mongolian plateau

    Science.gov (United States)

    Brown, Daniel G.; Agrawal, Arun; Sass, Daniel A.; Wang, Jun; Hua, Jin; Xie, Yichun

    2013-12-01

    Climate changes on the Mongolian Plateau are creating new challenges for the households and communities of the region. Much of the existing research on household choices in response to climate variability and change focuses on environmental risks and stresses. In contrast, our analysis highlights the importance of taking into account environmental and economic opportunities in explaining household adaptation choices. We surveyed over 750 households arrayed along an ecological gradient and matched across the national border in Mongolia and the Inner Mongolia Autonomous Region, China, asking what changes in livelihoods strategies households made over the last ten years, and analyzed these choices in two broad categories of options: diversification and livestock management. We combined these data with remotely sensed information about vegetation growth and self-reported exposure to price fluctuations. Our statistical results showed that households experiencing lower ecological and economic variability, higher average levels of vegetation growth, and with greater levels of material wealth, were often those that undertook more actions to improve their conditions in the face of variability. The findings have implications both for how interventions aimed at supporting ongoing choices might be targeted and for theory construction related to social adaptation.

  19. Productivity changes in the Mediterranean Sea for the 21st century in response to changes in the regional atmospheric forcing

    Directory of Open Access Journals (Sweden)

    Diego M Macias

    2015-10-01

    Full Text Available The Mediterranean Sea is considered as a hotspot for climate change because of its location in the temperate region and because it is a semi-enclosed basin surrounded by highly populated and developed countries. Some expected changes include an increase in air temperature and changes in the periodicity and spatial distribution of rainfall. Alongside, demographic and politics changes will alter freshwater quantity and quality. All these changes will have an impact on the ecological status of marine ecosystems in the basin. We use a 3D hydrodynamic-biogeochemical coupled model of the entire Mediterranean Sea to explore potential changes in primary productivity (mean values and spatial distribution under two emission scenarios (rcp4.5 and rcp8.5.To isolate the effects of changes in atmospheric conditions alone, in this ensemble of simulations rivers conditions (water flow and nutrient concentrations are kept unchanged and equal to its climatological values for the last 10 years. Despite the significant warming trend, the mean integrated primary production rate in the entire basin remains almost unchanged. However characteristic spatial differences are consistently found in the different simulations. The western basin becomes more oligotrophic associated to a surface density decrease (increase stratification because of the influence of the Atlantic waters which prevents surface salinity to increase. In the eastern basin, on the contrary, all model runs simulates an increase in surface production linked to a density increase (less stratification because of the increasing evaporation rate. The simulations presented here demonstrate the basic response patterns of the Mediterranean Sea ecosystem to changing climatological conditions. Although unlikely, they could be considered as a ‘baseline’ of expected consequences of climatic changes on marine conditions in the Mediterranean.

  20. Predictors of technical adoption and behavioural change to transport energy-saving measures in response to climate change

    International Nuclear Information System (INIS)

    Energy conservation can be achieved through the adoption of technical measures or the changing of one's behaviour. A survey of 201 Malaysian public personnel was conducted to examine the predictors of these two types of transport energy-saving measures in response to climate change. The results indicated that there were significant differences in the relative acceptability of both behavioural measures with respect to gender, level of education, income, knowledge of climate change and attitude. Gender, knowledge of causes of climate change and personal norm were predictors for the acceptability of technical measures, while perceived efficacy and personal norm were the factors that influenced the acceptability of behavioural measures. The results also indicated that distinctions ought to be made between technology adoption and behaviour modifications that require lifestyle changes when assessing pro-environmental intent behaviour. The implications for theory and practice are discussed. - Highlights: • A survey was conducted to examine acceptability of transport energy-saving measures. • Gender, knowledge of causes, efficacy and personal norm are predictors of technical measures. • Personal norm and perceived efficacy influenced acceptability of behavioural change. • Both measures are strongly correlated to psychological factors than to socio-demographic variables