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Changes

Distribution by Scientific Domains
Medical Sciences34%
Life Sciences24%
Chemistry8%
Humanities and Social Sciences7%
Earth and Environmental Science6%
Business, Economics, Finance and Accounting5%
Polymers and Materials Science2%
Psychology2%
Engineering2%
5 Other Domains10%

Kinds of Changes

  • Gibb free energy change
  • abnormal change
  • abrupt change
  • abrupt climate change
  • absolute change
  • absorption change
  • abundance change
  • accompanying change
  • account change
  • accounting change
  • acid change
  • activity change
  • activity-dependent change
  • actual change
  • acute change
  • adaptive change
  • additional change
  • adverse change
  • affective change
  • affinity change
  • age change
  • age relate change
  • age-associated change
  • age-dependent change
  • age-related change
  • aging change
  • agrarian change
  • agricultural change
  • amino acid change
  • amplitude change
  • anatomic change
  • anatomical change
  • annual change
  • annual percent change
  • annual percentage change
  • anthropogenic change
  • anthropogenic climate change
  • anthropogenic environmental change
  • apoptotic change
  • apparent change
  • appreciable change
  • architectural change
  • area change
  • arterial change
  • assemblage change
  • atherosclerotic change
  • atrophic change
  • attitude change
  • attitudinal change
  • auditor change
  • autonomic change
  • average change
  • base change
  • base-level change
  • behavior change
  • behavioral change
  • behaviour change
  • behavioural change
  • beneficial change
  • biochemical change
  • biodiversity change
  • biological change
  • biomechanical change
  • blood flow change
  • blood pressure change
  • bmd change
  • bodily change
  • body change
  • body composition change
  • body mass change
  • body shape change
  • body weight change
  • bold change
  • bold signal change
  • bone change
  • bone level change
  • bone-level change
  • borderline change
  • bp change
  • brain change
  • broader change
  • ca2+ change
  • capacity change
  • cardiac change
  • cardiovascular change
  • cause change
  • cbf change
  • cbv change
  • cell change
  • cellular change
  • character change
  • characteristic change
  • chemical change
  • chemical shift change
  • chromatin change
  • chromosomal change
  • chronic change
  • circadian change
  • circulation change
  • circulatory change
  • clear cell change
  • clear change
  • climate change
  • climate-driven change
  • climatic change
  • clinical change
  • co2 change
  • coastal change
  • cognitive change
  • color change
  • colour change
  • common change
  • community change
  • community-level change
  • comparable change
  • comparing change
  • compensatory change
  • complex change
  • composition change
  • compositional change
  • concentration change
  • conceptual change
  • conclusion change
  • concomitant change
  • concurrent change
  • configurational change
  • conformation change
  • conformational change
  • consequent change
  • considerable change
  • consistent change
  • constant change
  • constitutional change
  • contemporary change
  • contextual change
  • continuous change
  • copy number change
  • corresponding change
  • cortical change
  • course change
  • cover change
  • critical change
  • cultural change
  • culture change
  • current change
  • curriculum change
  • cycle change
  • cyclic change
  • cyclical change
  • cystic change
  • cytokine change
  • cytoskeletal change
  • daily change
  • decadal change
  • definite change
  • degenerative change
  • democratic change
  • demographic change
  • density change
  • dependent change
  • design change
  • desired change
  • detectable change
  • detecting change
  • determine change
  • development change
  • developmental change
  • diagenetic change
  • diameter change
  • diel change
  • diet change
  • dietary change
  • different change
  • differential change
  • dimensional change
  • directional change
  • disc change
  • discernible change
  • discontinuous change
  • discrete change
  • distinct change
  • distribution change
  • diurnal change
  • diversity change
  • dividend change
  • dna change
  • dna copy number change
  • dosage change
  • dose change
  • dose-dependent change
  • dramatic change
  • drastic change
  • dressing change
  • dynamic change
  • dysplastic change
  • earliest change
  • early change
    		•
  • early structural change
  • ecg change
  • ecological change
  • economic change
  • ecosystem change
  • educational change
  • eeg change
  • effecting change
  • effects change
  • efficiency change
  • electrical change
  • electrocardiographic change
  • electrophysiologic change
  • electrophysiological change
  • elevation change
  • emg change
  • emotional change
  • emphysematous change
  • employment change
  • endocrine change
  • enduring change
  • energy change
  • enormous change
  • enthalpy change
  • entropy change
  • environment change
  • environmental change
  • epidermal change
  • epigenetic change
  • epithelial change
  • evolutionary change
  • exchange rate change
  • excitability change
  • exogenous change
  • expected change
  • expression change
  • expression level change
  • expressional change
  • extensive change
  • extreme change
  • facy change
  • family change
  • far-reaching change
  • fatty change
  • favorable change
  • favourable change
  • fertility change
  • few change
  • fibrocystic change
  • fibrotic change
  • field change
  • flavor change
  • floristic change
  • flow change
  • fluorescence change
  • flux change
  • focal change
  • fold change
  • forest change
  • fractional change
  • free energy change
  • frequency change
  • frequent change
  • function change
  • functional change
  • fundamental change
  • future change
  • future climate change
  • future environmental change
  • gene change
  • gene expression change
  • general change
  • generator change
  • genetic change
  • genomic change
  • geochemical change
  • geological change
  • geometric change
  • geometry change
  • global change
  • global climate change
  • global environmental change
  • governance change
  • gradient change
  • gradual change
  • great change
  • greater change
  • greatest change
  • gross change
  • group change
  • growth change
  • habitat change
  • haematological change
  • haemodynamic change
  • hba1c change
  • health behavior change
  • health change
  • heart rate change
  • heat capacity change
  • height change
  • hematological change
  • hemodynamic change
  • hemoglobin change
  • heritable change
  • high signal change
  • hippocampal change
  • histologic change
  • histological change
  • histomorphologic change
  • histopathologic change
  • histopathological change
  • historical change
  • history change
  • holocene climate change
  • holocene environmental change
  • hormonal change
  • hr change
  • hydrological change
  • hypertrophic change
  • image change
  • imaging change
  • immediate change
  • immune change
  • immunological change
  • impedance change
  • implementing change
  • important change
  • income change
  • incremental change
  • independent change
  • index change
  • indirect change
  • individual change
  • induced change
  • inflammatory change
  • influence change
  • insignificant change
  • institutional change
  • intense change
  • intensity change
  • interannual change
  • interest rate change
  • interesting change
  • interface change
  • internal change
  • interval change
  • intracellular change
  • intrinsic change
  • involving change
  • irreversible change
  • ischaemic change
  • ischemic change
  • karyotypic change
  • key change
  • label change
  • land cover change
  • land use change
  • land-cover change
  • land-use change
  • language change
  • large change
  • large conformational change
  • large-scale change
  • larger change
  • largest change
  • lasting change
  • late holocene environmental change
  • lateral change
  • latter change
  • legal change
  • legislative change
  • length change
  • level change
  • life change
  • life history change
  • lifestyle change
  • likely change
  • linear change
  • lipid change
  • little change
  • load change
  • local change
  • local conformational change
  • local structural change
  • localized change
  • long-lasting change
  • long-term change
  • long-term climate change
  • longer-term change
  • longitudinal change
  • main change
  • major change
  • major conformational change
  • major morphological change
  • major policy change
  • major structural change
  • making change
    		•
  • malignant change
  • management change
  • many change
  • map change
  • marginal change
  • marked change
  • market change
  • mass change
  • matrix change
  • matter change
  • maturational change
  • maximal change
  • maximum change
  • mean change
  • mean percentage change
  • meaningful change
  • measurable change
  • measure change
  • measuring change
  • mechanical change
  • median change
  • medication change
  • medium change
  • membrane potential change
  • metabolic change
  • metabolite change
  • metaplastic change
  • methylation change
  • microscopic change
  • microstructural change
  • microstructure change
  • microvascular change
  • mild change
  • minimal change
  • minor change
  • missense change
  • mitochondrial change
  • moderate change
  • modest change
  • molecular change
  • monetary policy change
  • monitoring change
  • mood change
  • morphologic change
  • morphological change
  • morphology change
  • morphometric change
  • mri change
  • mrna change
  • mucosal change
  • multiple change
  • mutational change
  • myopathic change
  • nail change
  • name change
  • natural change
  • necrotic change
  • negative change
  • negligible change
  • neoplastic change
  • nervous system change
  • net change
  • neural change
  • neurobiological change
  • neurochemical change
  • neurodegenerative change
  • neuronal change
  • neuropathological change
  • neurophysiological change
  • neuroplastic change
  • night change
  • no change
  • non-linear change
  • non-significant change
  • normative change
  • notable change
  • noticeable change
  • novel change
  • nuclear change
  • nucleotide change
  • number change
  • numerical change
  • numerous change
  • nutritional change
  • observable change
  • observed change
  • obvious change
  • occupational change
  • ocular change
  • of change
  • ongoing change
  • ongoing climate change
  • only change
  • only minor change
  • only modest change
  • only slight change
  • only small change
  • ontogenetic change
  • operational change
  • opinion change
  • opposite change
  • optical change
  • organisational change
  • organizational change
  • orientation change
  • other change
  • output change
  • ownership change
  • oxidative change
  • oxygenation change
  • palaeoclimatic change
  • parallel change
  • parameter change
  • past change
  • past climate change
  • past environmental change
  • pathologic change
  • pathological change
  • pathophysiological change
  • pattern change
  • percent change
  • percentage change
  • performance change
  • perfusion change
  • period change
  • periodic change
  • permanent change
  • persistent change
  • personal change
  • personality change
  • ph change
  • pharmacokinetic change
  • phase change
  • phenological change
  • phenotype change
  • phenotypic change
  • physical change
  • physicochemical change
  • physiologic change
  • physiological change
  • pigmentary change
  • pigmentation change
  • plastic change
  • platelet shape change
  • pleistocene climate change
  • policy change
  • political change
  • population change
  • porosity change
  • position change
  • positional change
  • positive change
  • possible change
  • postnatal change
  • postoperative change
  • postural change
  • potential change
  • practical change
  • practice change
  • precipitation change
  • predictable change
  • predicted change
  • predicted climate change
  • predicting change
  • preference change
  • pressure change
  • price change
  • process change
  • productivity change
  • profile change
  • profound change
  • progressive change
  • projected change
  • projected climate change
  • proliferative change
  • prominent change
  • pronounced change
  • property change
  • proportional change
  • proposed change
  • protein change
  • protein conformational change
  • protein expression change
  • proteome change
  • psychological change
  • psychopathological change
  • qualitative change
  • quality change
  • quantitative change
  • quaternary climate change
  • radical change
  • radiographic change
  • radiological change
  • random change
  • range change
  • rapid change
  • rapid climate change
    		•
  • rapid evolutionary change
  • rate change
  • rating change
  • ratio change
  • reactive change
  • real change
  • recent change
  • recent climate change
  • recent policy change
  • redox change
  • reflex change
  • refractive index change
  • regime change
  • region-specific change
  • regional change
  • regional climate change
  • regressive change
  • regulatory change
  • relate change
  • relative change
  • relative sea-level change
  • relevant change
  • reliable change
  • religious change
  • remarkable change
  • repolarization change
  • reported change
  • resistance change
  • respiratory change
  • response change
  • result change
  • resultant change
  • resulting change
  • retinal change
  • reversible change
  • revolutionary change
  • rheological change
  • rhythmic change
  • role change
  • rural change
  • salinity change
  • same change
  • scale change
  • scattering change
  • score change
  • sea change
  • sea level change
  • sea-level change
  • seasonal change
  • secondary change
  • secondary structural change
  • secular change
  • segment change
  • selective change
  • sense change
  • sensitivity change
  • sensory change
  • sequence change
  • sequential change
  • sequential morphological change
  • serial change
  • several change
  • severe change
  • severe histopathological change
  • sex change
  • shape change
  • sharp change
  • shift change
  • short-term change
  • showed little change
  • showing change
  • signal change
  • signal intensity change
  • signaling change
  • significant change
  • significant colour change
  • significant conformational change
  • significant morphological change
  • significant structural change
  • similar change
  • simple change
  • simultaneous change
  • single nucleotide change
  • single-base change
  • site change
  • size change
  • skeletal change
  • skin change
  • slight change
  • slow change
  • slow conformational change
  • small change
  • small structural change
  • smaller change
  • social change
  • societal change
  • socio-economic change
  • socioeconomic change
  • soil change
  • spatial change
  • spatio-temporal change
  • spatiotemporal change
  • species change
  • species composition change
  • specific change
  • spectral change
  • spectroscopic change
  • spongiform change
  • spontaneous change
  • st change
  • st-segment change
  • state change
  • statistical change
  • status change
  • step change
  • storage change
  • strategic change
  • strategy change
  • stress change
  • striking change
  • stromal change
  • strong change
  • structural brain change
  • structural change
  • structure change
  • style change
  • subclinical change
  • subjective change
  • subsequent change
  • substantial change
  • substantive change
  • subtle change
  • subtle structural change
  • successional change
  • successive change
  • sudden change
  • surface change
  • sustainable change
  • symptom change
  • synaptic change
  • system change
  • systematic change
  • systemic change
  • tax change
  • technical change
  • technological change
  • temperature change
  • temperature-dependent change
  • temporal change
  • textural change
  • texture change
  • therapeutic change
  • thermal change
  • threshold change
  • time change
  • time course change
  • time-course change
  • time-dependent change
  • tissue change
  • tone change
  • tracking change
  • transcriptional change
  • transcriptome change
  • transformative change
  • transient change
  • treatment change
  • treatment-related change
  • tremendous change
  • ultrastructural change
  • underlying change
  • undesirable change
  • unexpected change
  • use change
  • value change
  • variety of change
  • various change
  • vascular change
  • vegetation change
  • velocity change
  • vertical change
  • very small change
  • viscosity change
  • visual change
  • volatility change
  • voltage change
  • volume change
  • volumetric change
  • wall change
  • water change
  • weight change
  • welfare change
  • white matter change
  • widespread change
  • work change
  • workplace change
  • year-to-year change

    • Terms modified by Changes

  • change agent
  • change agreement
  • change attributable
  • change characteristic
  • change consistent
  • change decreased
  • change detection
  • change direction
  • change disease
  • change effects
  • change effort
  • change factor
  • change impact
  • change in pain intensity
  • change in pain score
    		•
  • change index
  • change indicative
  • change initiative
  • change intervention
  • change issues
  • change leading
  • change little
  • change management
  • change material
  • change mechanism
  • change mitigation
  • change model
  • change models
  • change necessary
  • change need
    		•
  • change nephrotic syndrome
  • change occurring
  • change only
  • change pattern
  • change perspective
  • change point
  • change policy
  • change process
  • change programme
  • change project
  • change projection
  • change questionnaire
  • change rate
  • change relate
  • change research
    		•
  • change scenario
  • change score
  • change secondary
  • change similar
  • change society
  • change strategy
  • change studies
  • change suggestive
  • change temperature
  • change theory
  • change underlying
  • change world

    • Selected Abstracts

    ORGANIZATIONAL PORTFOLIO THEORY: PERFORMANCE-DRIVEN ORGANIZATIONAL CHANGE

    CONTEMPORARY ECONOMIC POLICY, Issue 4 2000
    L DONALDSON
    The article outlines some of the main ideas of a new organizational theory: organizational portfolio theory. The literature has empirically established that organizations tend not to make needed adaptive changes until they suffer a crisis of low organizational performance. Organizational portfolio theory takes this idea and constructs a theory of the conditions under which organizational performance becomes low enough for adaptive organizational change to occur. The focus is on the interaction between organizational misfit and the other causes of organizational performance. To model these interactions use is made of the concepts of risk and portfolio. [source]

    MUSEUMS AS AGENTS FOR SOCIAL AND POLITICAL CHANGE,

    CURATOR THE MUSEUM JOURNAL, Issue 3 2001
    DAWN CASEY
    First page of article [source]

    NATURAL ENVIRONMENTAL CHANGE edited by A. M. Mannion, Routledge, London, 1999.

    EARTH SURFACE PROCESSES AND LANDFORMS, Issue 8 2001
    No. of pages: 198.
    No abstract is available for this article. [source]

    CLIMATE CHANGE, LUDDITES AND UNNECESSARY DEATHS

    ECONOMIC AFFAIRS, Issue 1 2004
    Roger Bate
    No abstract is available for this article. [source]

    THE CONCEPT OF FUNDAMENTAL EDUCATIONAL CHANGE

    EDUCATIONAL THEORY, Issue 3 2007
    Leonard J Waks
    By distinguishing sharply between educational change at the organizational and the institutional levels, Waks shows that the mechanisms of change at these two levels are entirely different. He then establishes, by means of a conceptual argument, that fundamental educational change takes place not at the organizational, but rather at the institutional level. Along the way Waks takes Larry Cuban's influential conceptual framework regarding educational change as both a starting point and target of appraisal. [source]

    HARM REDUCTION IN THE UNITED STATES AT A MOMENT OF CHANGE: MOVING INNOVATION FROM GRASSROOTS TO MAINSTREAM?

    ADDICTION, Issue 9 2009
    JEAN-PAUL C. GRUND
    No abstract is available for this article. [source]

    [Commentary] TIME FOR A CHANGE OF PERSPECTIVE ON BEHAVIOUR CHANGE INTERVENTIONS?

    ADDICTION, Issue 6 2009
    JEAN ADAMS
    No abstract is available for this article. [source]

    A TEST OF THE NEUTRAL MODEL OF EXPRESSION CHANGE IN NATURAL POPULATIONS OF HOUSE MOUSE SUBSPECIES

    EVOLUTION, Issue 2 2010
    Fabian Staubach
    Changes in expression of genes are thought to contribute significantly to evolutionary divergence. To study the relative role of selection and neutrality in shaping expression changes, we analyzed 24 genes in three different tissues of the house mouse (Mus musculus). Samples from two natural populations of the subspecies M. m. domesticus and M. m. musculus were investigated using quantitative PCR assays and sequencing of the upstream region. We have developed an approach to quantify expression polymorphism within such populations and to disentangle technical from biological variation in the data. We found a correlation between expression polymorphism within populations and divergence between populations. Furthermore, we found a correlation between expression polymorphism and sequence polymorphism of the respective genes. These data are most easily interpreted within a framework of a predominantly neutral model of gene expression change, where only a fraction of the changes may have been driven by positive selection. Although most genes investigated were expressed in all three tissues analyzed, significant changes of expression levels occurred predominantly in a single tissue only. This adds to the notion that enhancer-specific effects or transregulatory effects can modulate the evolution of gene expression in a tissue-specific way. [source]

    EMPIRICAL COMPARISON OF G MATRIX TEST STATISTICS: FINDING BIOLOGICALLY RELEVANT CHANGE

    EVOLUTION, Issue 10 2009
    Brittny Calsbeek
    A central assumption of quantitative genetic theory is that the breeder's equation (R=GP,1S) accurately predicts the evolutionary response to selection. Recent studies highlight the fact that the additive genetic variance,covariance matrix (G) may change over time, rendering the breeder's equation incapable of predicting evolutionary change over more than a few generations. Although some consensus on whether G changes over time has been reached, multiple, often-incompatible methods for comparing G matrices are currently used. A major challenge of G matrix comparison is determining the biological relevance of observed change. Here, we develop a "selection skewers"G matrix comparison statistic that uses the breeder's equation to compare the response to selection given two G matrices while holding selection intensity constant. We present a bootstrap algorithm that determines the significance of G matrix differences using the selection skewers method, random skewers, Mantel's and Bartlett's tests, and eigenanalysis. We then compare these methods by applying the bootstrap to a dataset of laboratory populations of Tribolium castaneum. We find that the results of matrix comparison statistics are inconsistent based on differing a priori goals of each test, and that the selection skewers method is useful for identifying biologically relevant G matrix differences. [source]

    RESURRECTING THE ROLE OF TRANSCRIPTION FACTOR CHANGE IN DEVELOPMENTAL EVOLUTION

    EVOLUTION, Issue 9 2008
    Vincent J. Lynch
    A long-standing question in evolutionary and developmental biology concerns the relative contribution of cis- regulatory and protein changes to developmental evolution. Central to this argument is which mutations generate evolutionarily relevant phenotypic variation? A review of the growing body of evolutionary and developmental literature supports the notion that many developmentally relevant differences occur in the cis -regulatory regions of protein-coding genes, generally to the exclusion of changes in the protein-coding region of genes. However, accumulating experimental evidence demonstrates that many of the arguments against a role for proteins in the evolution of gene regulation, and the developmental evolution in general, are no longer supported and there is an increasing number of cases in which transcription factor protein changes have been demonstrated in evolution. Here, we review the evidence that cis- regulatory evolution is an important driver of phenotypic evolution and provide examples of protein-mediated developmental evolution. Finally, we present an argument that the evolution of proteins may play a more substantial, but thus far underestimated, role in developmental evolution. [source]

    THE CHANGE IN QUANTITATIVE GENETIC VARIATION WITH INBREEDING

    EVOLUTION, Issue 12 2006
    Josh Van Buskirk
    Abstract Inbreeding is known to reduce heterozygosity of neutral genetic markers, but its impact on quantitative genetic variation is debated. Theory predicts a linear decline in additive genetic variance (VA) with increasing inbreeding coefficient (F) when loci underlying the trait act additively, but a nonlinear hump-shaped relationship when dominance and epistasis are important. Predictions for heritability (h2) are similar, although the exact shape depends on the value of h2 in the absence of inbreeding. We located 22 published studies in which the level of genetic variation in [source]

    THE PHYLOGENETIC PATTERN OF SPECIATION AND WING PATTERN CHANGE IN NEOTROPICAL ITHOMIA BUTTERFLIES (LEPIDOPTERA: NYMPHALIDAE)

    EVOLUTION, Issue 7 2006
    Chris D. Jiggins
    Abstract Species level phylogenetic hypotheses can be used to explore patterns of divergence and speciation. In the tropics, speciation is commonly attributed to either vicariance, perhaps within climate-induced forest refugia, or ecological speciation caused by niche adaptation. Mimetic butterflies have been used to identify forest refugia as well as in studies of ecological speciation, so they are ideal for discriminating between these two models. The genus Ithomia contains 24 species of warningly colored mimetic butterflies found in South and Central America, and here we use a phylogenetic hypothesis based on seven genes for 23 species to investigate speciation in this group. The history of wing color pattern evolution in the genus was reconstructed using both parsimony and likelihood. The ancestral pattern for the group was almost certainly a transparent butterfly, and there is strong evidence for convergent evolution due to mimicry. A punctuationist model of pattern evolution was a significantly better fit to the data than a gradualist model, demonstrating that pattern changes above the species level were associated with cladogenesis and supporting a model of ecological speciation driven by mimicry adaptation. However, there was only one case of sister species unambiguously differing in pattern, suggesting that some recent speciation events have occurred without pattern shifts. The pattern of geographic overlap between clades over time shows that closely related species are mostly sympatric or, in one case, parapatric. This is consistent with modes of speciation with ongoing gene flow, although rapid range changes following allopatric speciation could give a similar pattern. Patterns of lineage accumulation through time differed significantly from that expected at random, and show that most of the extant species were present by the beginning of the Pleistocene at the latest. Hence Pleistocene refugia are unlikely to have played a major role in Ithomia diversification. [source]

    ADAPTIVE CHANGE IN THE RESOURCE-EXPLOITATION TRAITS OF A GENERALIST CONSUMER: THE CEOLUTION AND COEXISTENCE OF GENERALISTS AND SPECIALISTS

    EVOLUTION, Issue 3 2006
    Peter A. Abrams
    Abstract Mathematical models of consumer-resource systems are used to explore the evolution of traits related to resource acquisition in a generalist consumer species that is capable of exploiting two resources. The analysis focuses on whether evolution of traits determining the capture rates of two resources by a consumer species produce one generalist, two specialists, or all three types, when all types are characterized by a common fitness function. In systems with a stable equilibrium, evolution produces one generalist or two specialists, depending on the second derivative of the trade-off relationship. When there are sustained population fluctuations, the nature of the trade-off between the consumer's capture rates of the two resources still plays a key role in determining the evolutionary outcome. If the trade-off is described by a choice variable between zero and one that is raised to a power n, polymorphic states are possible when n > 1, which implies a positive second derivative of the curve. These states are either dimorphism, with two relatively specialized consumer types, or trimorphism, with a single generalist type and two specialists. Both endogenously driven consumer-resource cycles, and fluctuations driven by an environmental variable affecting resource growth are considered. Trimorphic evolutionary outcomes are relatively common in the case of endogenous cycles. In contrast to a previous study, these trimorphisms can often evolve even when new lineages are constrained to have phenotypes very similar to existing lineages. Exogenous cycles driven by environmental variation in resource growth rates appear to be much less likely to produce a mixture of generalists and specialists than are endogenous consumer-resource cycles. [source]

    EPISTASIS AND THE TEMPORAL CHANGE IN THE ADDITIVE VARIANCE-COVARIANCE MATRIX INDUCED BY DRIFT

    EVOLUTION, Issue 8 2004
    Carlos López-Fanjul
    Abstract The effect of population bottlenecks on the components of the genetic covariance generated by two neutral independent epistatic loci has been studied theoretically (additive, covA; dominance, covD; additive-by-additive, covAA; additive-by-dominance, covAD; and dominance-by-dominance, covDD). The additive-by-additive model and a more general model covering all possible types of marginal gene action at the single-locus level (additive/dominance epistatic model) were considered. The covariance components in an infinitely large panmictic population (ancestral components) were compared with their expected values at equilibrium over replicates randomly derived from the base population, after t consecutive bottlenecks of equal size N (derived components). Formulae were obtained in terms of the allele frequencies and effects at each locus, the corresponding epistatic effects and the inbreeding coefficient Ft. These expressions show that the contribution of nonadditive loci to the derived additive covariance (covAt) does not linearly decrease with inbreeding, as in the pure additive case, and may initially increase or even change sign in specific situations. Numerical examples were also analyzed, restricted for simplicity to the case of all covariance components being positive. For additive-by-additive epistasis, the condition covAt > covA only holds for high frequencies of the allele decreasing the metric traits at each locus (negative allele) if epistasis is weak, or for intermediate allele frequencies if it is strong. For the additive/dominance epistatic model, however, covAt > covA applies for low frequencies of the negative alleles at one or both loci and mild epistasis, but this result can be progressively extended to intermediate frequencies as epistasis becomes stronger. Without epistasis the same qualitative results were found, indicating that marginal dominance induced by epistasis can be considered as the primary cause of an increase of the additive covariance after bottlenecks. For all models, the magnitude of the ratio covAt/covA was inversely related to N and t. [source]

    MANAGEMENT ACCOUNTING CHANGE AND NEW PUBLIC MANAGEMENT IN LOCAL GOVERNMENT: A REASSESSMENT OF AMBITIONS AND RESULTS , AN INSTITUTIONALIST APPROACH TO ACCOUNTING CHANGE IN THE DUTCH PUBLIC SECTOR

    FINANCIAL ACCOUNTABILITY & MANAGEMENT, Issue 3 2008
    Henk J. Ter Bogt
    Dutch municipalities and provinces, denoted here as local government, have seen a succession of changes in their management accounting systems and have also introduced other changes related to New Public Management (NPM) in the last twenty years. This paper examines accounting changes, such as the introduction of accrual accounting, output and outcome budgets and performance measurement, from an institutionalist point of view. The paper presents experiences of 23 politicians and professional managers with the various changes over a period of fifteen to twenty years. The interviewees, just like various researchers in the field of NPM, were critical of the accounting changes and their effects. However, several of them also made clear that, seen over the long run, the changes did have some effects that they liked and seem to be in line with the ,ideals' presented in NPM literature. The paper suggests that an institutionalist perspective is helpful for studying change processes in organizations and for observing factors and developments that might not be noticed when a more functional and short-term perspective is adopted. [source]

    INTEGRATED LANDSCAPE ANALYSES OF CHANGE OF MIOMBO WOODLAND IN TANZANIA AND ITS IMPLICATION FOR ENVIRONMENT AND HUMAN LIVELIHOOD

    GEOGRAFISKA ANNALER SERIES A: PHYSICAL GEOGRAPHY, Issue 1 2009
    LENNART STRÖMQUIST
    ABSTRACT. Landscapes bear witness to past and present natural and societal processes influencing the environment and human livelihoods. By analysing landscape change at different spatial scales over time the effects on the environment and human livelihoods of various external and internal driving forces of change can be studied. This paper presents such an analysis of miombo woodland surrounding the Mkata plains in central Tanzania. The rich natural landscape diversity of the study area in combination with its historical and political development makes it an ideal observation ground for this kind of study. The paper focuses on long-term physical and biological changes, mainly based on satellite information but also on field studies and a review of documents and literature. The miombo woodlands are highly dynamic semi-arid ecosystems found on a number of nutrient-poor soil groups. Most of the woodlands are related to an old, low-relief geomorphology of erosion surfaces with relatively deep and leached soils, or to a lesser extent also on escarpments and steep Inselberg slopes with poor soils. Each period in the past has cast its footprints on the landscape development and its potential for a sustainable future use. On a regional level there has been a continual decrease in forest area over time. Expansion of agriculture around planned villages, implemented during the 1970s, in some cases equals the loss of forest area (Mikumi-Ulaya), whilst in other areas (Kitulangalo), the pre-independence loss of woodland was small; the agricultural area was almost the same during the period 1975,1999, despite the fact that forests have been lost at an almost constant rate over the same period. Illegal logging and charcoal production are likely causes because of the proximity to the main highway running through the area. Contrasting to the general regional pattern are the conditions in a traditional village (Ihombwe), with low immigration of people and a maintained knowledge of the resource potential of the forest with regards to edible plants and animals. In this area the local community has control of the forest resources in a Forest Reserve, within which the woody vegetation has increased in spite of an expansion of agriculture on other types of village land. The mapping procedure has shown that factors such as access to transport and lack of local control have caused greater deforestation of certain areas than during the colonial period. Planned villages have furthermore continued to expand over forest areas well after their implementation, rapidly increasing the landscape fragmentation. One possible way to maintain landscape and biodiversity values is by the sustainable use of traditional resources, based on local knowledge of their management as illustrated by the little change observed in the traditionally used area. [source]

    THE RESPONSE OF PARTIALLY DEBRIS-COVERED VALLEY GLACIERS TO CLIMATE CHANGE: THE EXAMPLE OF THE PASTERZE GLACIER (AUSTRIA) IN THE PERIOD 1964 TO 2006

    GEOGRAFISKA ANNALER SERIES A: PHYSICAL GEOGRAPHY, Issue 4 2008
    ANDREAS KELLERER-PIRKLBAUER
    ABSTRACT. Long-term observations of partly debris-covered glaciers have allowed us to assess the impact of supra-glacial debris on volumetric changes. In this paper, the behaviour of the partially debris-covered, 3.6 km2 tongue of Pasterze Glacier (47°05,N, 12°44,E) was studied in the context of ongoing climate changes. The right part of the glacier tongue is covered by a continuous supra-glacial debris mantle with variable thicknesses (a few centimetres to about 1 m). For the period 1964,2000 three digital elevation models (1964, 1981, 2000) and related debris-cover distributions were analysed. These datasets were compared with long-term series of glaciological field data (displacement, elevation change, glacier terminus behaviour) from the 1960s to 2006. Differences between the debriscovered and the clean ice parts were emphasised. Results show that volumetric losses increased by 2.3 times between the periods 1964,1981 and 1981,2000 with significant regional variations at the glacier tongue. Such variations are controlled by the glacier emergence velocity pattern, existence and thickness of supra-glacial debris, direct solar radiation, counter-radiation from the valley sides and their changes over time. The downward-increasing debris thickness is counteracting to a compensational stage against the common decrease of ablation with elevation. A continuous debris cover not less than 15 cm in thickness reduces ablation rates by 30,35%. No relationship exists between glacier retreat rates and summer air temperatures. Substantial and varying differences of the two different terminus parts occurred. Our findings clearly underline the importance of supra-glacial debris on mass balance and glacier tongue morphology. [source]

    A 2000-YEAR CONTEXT FOR MODERN CLIMATE CHANGE

    GEOGRAFISKA ANNALER SERIES A: PHYSICAL GEOGRAPHY, Issue 1 2005
    K.A. MAASCH
    ABSTRACT. Although considerable attention has been paid to the record of temperature change over the last few centuries, the range and rate of change of atmospheric circulation and hydrology remain elusive. Here, eight latitudinally well-distributed (pole-equator-pole), highly resolved (annual to decadal) climate proxy records are presented that demonstrate major changes in these variables over the last 2000 years. A comparison between atmospheric 14C and these changes in climate demonstrates a first-order relationship between a variable Sun and climate. The relationship is seen on a global scale. [source]

    "OUR HOME IS DROWNING": IÑUPIAT STORYTELLING AND CLIMATE CHANGE IN POINT HOPE, ALASKA,

    GEOGRAPHICAL REVIEW, Issue 4 2008
    CHIE SAKAKIBARA
    ABSTRACT. Contemporary storytelling among the IÑupiat of Point Hope, Alaska, is a means of coping with the unpredictable future that climate change poses. Arctic climate change impacts IÑupiat lifeways on a cultural level by threatening their homeland, their sense of place, and their respect for the bowhead whale that is the basis of their cultural identity. What I found during my fieldwork was that traditional storytelling processed environmental changes as a way of maintaining a connection to a disappearing place. In this article I describe how environmental change is culturally manifest through tales of the supernatural, particularly spirit beings or ghosts. The types of IÑupiat stories and modes of telling them reveal people's uncertainty about the future. Examining how people perceive the loss of their homeland, I argue that IÑupiat storytelling both reveals and is a response to a changing physical and spiritual landscape. [source]

    ALPINE AREAS IN THE COLORADO FRONT RANGE AS MONITORS OF CLIMATE CHANGE AND ECOSYSTEM RESPONSE,

    GEOGRAPHICAL REVIEW, Issue 2 2002
    MARK W. WILLIAMS
    ABSTRACT. The presence of a seasonal snowpack in alpine environments can amplify climate signals. A conceptual model is developed for the response of alpine ecosystems in temperate, midlatitude areas to changes in energy, chemicals, and water, based on a case study from Green Lakes Valley,Niwot Ridge, a headwater catchment in the Colorado Front Range. A linear regression shows the increase in annual precipitation of about 300 millimeters from 1951 to 1996 to be significant. Most of the precipitation increase has occurred since 1967. The annual deposition of inorganic nitrogen in wetfall at the Niwot Ridge National Atmospheric Deposition Program site roughly doubled between 1985,1988 and 1989,1992. Storage and release of strong acid anions, such as those from the seasonal snowpack in an ionic pulse, have resulted in episodic acidification of surface waters. These biochemical changes alter the quantity and quality of organic matter in high-elevation catchments of the Rocky Mountains. Affecting the bottom of the food chain, the increase in nitrogen deposition may be partly responsible for the current decline of bighorn sheep in the Rocky Mountains. [source]

    HALF A CENTURY OF CROPLAND CHANGE,

    GEOGRAPHICAL REVIEW, Issue 3 2001
    JOHN FRASER HART
    ABSTRACT. The census concept of total cropland is a better measure of effective agricultural land than is total farmland, which includes extensive areas of woodland owned by farmers. The cropland area of the United States dropped from 478 million acres in 1949 to 431 million acres in 1997, for a net loss of less than 1 million acres, or roughly one-fifth of 1 percent, per year. In the midwestern agricultural heartland most counties changed less than 5 percent in the half-century, and more counties gained than lost. The West was a crazy quilt of change, and in the East most counties lost more than 10 percent. Major metropolitan counties lost a few percentage points more than did adjacent areas, but at a lower rate per capita than the nation as a whole. Most of the loss of cropland was in marginal agricultural counties with soils of low inherent fertility and topography unsuited to modern farm machinery. The loss of cropland to suburban encroachment may be cause for intense local concern, but attempts to thwart development cannot be justified on grounds of a net national loss of good cropland. [source]

    MAKING SENSE OF CONCEPTUAL CHANGE

    HISTORY AND THEORY, Issue 3 2008
    JOUNI-MATTI KUUKKANEN
    ABSTRACT Arthur Lovejoy's history of unit-ideas and the history of concepts are often criticized for being historically insensitive forms of history-writing. Critics claim that one cannot find invariable ideas or concepts in several contexts or times in history without resorting to some distortion. One popular reaction is to reject the history of ideas and concepts altogether, and take linguistic entities as the main theoretical units. Another reaction is to try to make ideas or concepts context-sensitive and to see their histories as dynamic processes of transformation. The main argument in this paper is that we cannot abandon ideas or concepts as theoretical notions if we want to write an intelligible history of thought. They are needed for the categorization and classification of thinking, and in communication with contemporaries. Further, the criterion needed to subsume historical concepts under a general concept cannot be determined merely on the basis of their family resemblances, which allows variation without an end, since talk of the same concepts implies that they share something in common. I suggest that a concept in history should be seen to be composed of two components: the core of a concept and the margin of a concept. On the basis of this, we can develop a vocabulary for talking about conceptual changes. The main idea is that conceptual continuity requires the stability of the core of the concept, but not necessarily that of the margin, which is something that enables a description of context-specific features. If the core changes, we ought to see it as a conceptual replacement. [source]

    FROM MANAGEMENT TO VISION: ISSUES FOR BRITISH CHURCHES NEGOTIATING DECLINE AND CHANGE,

    INTERNATIONAL REVIEW OF MISSION, Issue 364 2003
    Simon Barrow
    First page of article [source]

    CLIMATE CHANGE: Copenhagen Summit

    AFRICA RESEARCH BULLETIN: ECONOMIC, FINANCIAL AND TECHNICAL SERIES, Issue 12 2010
    Article first published online: 9 FEB 2010
    No abstract is available for this article. [source]

    CLIMATE CHANGE: Ministerial Conference

    AFRICA RESEARCH BULLETIN: ECONOMIC, FINANCIAL AND TECHNICAL SERIES, Issue 12 2009
    Article first published online: 6 FEB 200
    No abstract is available for this article. [source]

    PARADIGM OF CHANGE (YI ?) IN CLASSICAL CHINESE PHILOSOPHY: PART I

    JOURNAL OF CHINESE PHILOSOPHY, Issue 4 2009
    CHUNG-YING CHENG
    [source]

    RIGHTING THE NAMES OF CHANGE

    JOURNAL OF CHINESE PHILOSOPHY, Issue 1 2009
    C. WESLEY DEMARCO
    [source]

    ORGANIZATIONAL CHANGE, SKILL FORMATION, HUMAN CAPITAL MEASUREMENT: EVIDENCE FROM ITALIAN MANUFACTURING FIRMS

    JOURNAL OF ECONOMIC SURVEYS, Issue 2 2010
    Gilberto Antonelli
    Abstract This paper emphasizes the role of labour demand as a determinant of human capital formation. After a section in which the alternative conceptions on the functioning of labour markets are presented and different ways of measuring human capital are compared, an applied analysis is carried out in which we provide a labour-demand-oriented measure of human capital, as defined by the amount of specific skills firms generate through work-based training (WBT) activities. By merging three rich firm-level datasets, we estimate the impact of a set of variables supposed to affect both the propensity to invest in WBT and the intensity of training within the Italian manufacturing industry over the period 2001,2005. Special attention is devoted to the variables characterizing within-firm organization of knowledge, organizational change and the formation of competence pipelines: among them, innovation, internationalization commitment, out-sourcing and new hirings. The estimates show that the effect of innovation on WBT is higher when the introduction of new technologies is supported by organizational innovations. When looking at the nature of WBT, we investigate the different determinants of the firms' propensity to provide both in-house and outside training. We measure training intensity in terms, respectively, of the number of provided training activities, private and total training costs and share of trainees. [source]

    CHARACTERISTICS OF CHAMBER TEMPERATURE CHANGE DURING VACUUM COOLING

    JOURNAL OF FOOD PROCESS ENGINEERING, Issue 2 2009
    RUI ZHAO
    ABSTRACT In order to investigate the dynamic changing pattern of the chamber temperature with chamber pressure during vacuum cooling, 10 repeated experiments were conducted to evaluate the time-dependent temperature and pressure in the vacuum chamber during vacuum cooling of water. Water was chosen in the experiment as it is the main component of most foods. The results showed that the temperature in the vacuum chamber significantly depended on variation in pressure at different pumping stages. The temperature changes in the chamber generally followed a certain pattern. In the early stage of vacuum cooling, the chamber temperature dropped very quickly (0.26 K/s), while at the end of vacuum cooling, it increased rapidly (0.22 K/s), and was about 11.8 K higher than the ambient temperature when the vacuum was released with ambient air flowing back to the chamber. PRACTICAL APPLICATIONS Vacuum cooling is a rapid cooling method for the food industry; further understanding of the vacuum cooling mechanism can help to control and improve this cooling process. Temperature changing pattern and distribution affects the quality of the food product in vacuum cooling process. As the main component of most foods is water, it is necessary to investigate the dynamic temperature changing pattern and distribution with vacuum pressure during vacuum cooling of water so that the information obtained could be used as a reference for vacuum cooling of food products. [source]

    KINETICS of QUALITY CHANGE DURING COOKING and FRYING of POTATOES: PART I. TEXTURE

    JOURNAL OF FOOD PROCESS ENGINEERING, Issue 4 2003
    F. NOURIAN
    ABSTRACT Kinetics of texture change during cooking and frying of potatoes were evaluated in this study. Potatoes were cut into cylinders (diameter × height: 20 mm × 20 mm for cooking, and 10 mm × 20 mm for frying) and cooked in a temperature controlled water bath at 80,100C or fried in a commercial fryer at 160,190C for selected times. the cooked samples were water cooled while the fried samples were air cooled immediately after the treatment. Test samples were then subjected to a single cycle compression test in a computer interfaced Universal Testing Machine and three textural properties (hardness, stiffness and firmness) were derived from the resulting force-deformation curves. Texture parameters of cooked potatoes decreased with progress of cooking time and the rate of texture changes associated with each temperature was found to be consistent with two pseudo first-order kinetic mechanisms, one more rapid than the other. Textural values of fried potatoes were found to increase with frying time and also followed a first order kinetic model. Temperature sensitivity of rate constants was adequately described by Arrhenius and z-value models. [source]