bluuebunny/crossref_metadata_2025_split huggingface dataset:
Deficiency of a Plastidial Adenylate Kinase in Arabidopsis Results in Elevated Photosynthetic Amino Acid Biosynthesis and Enhanced Growth
Authors: Carrari Fernando , Coll-Garcia Danahe , Schauer Nicolas , Lytovchenko Anna , Palacios-Rojas Natalia , Balbo Ilse , Rosso Mario , Fernie Alisdair R. 
Published: December 2004

Abstract
An Arabidopsis (Arabidopsis thaliana) L. Heynh mutant deficient in an isoform of adenylate kinase (ADK; At2g37250) was isolated by reverse genetics. It contains a T-DNA insertion 377 bp downstream of the start point of transcription. The mutant lacks At2g37250 transcripts and has a mild reduction in total cellular ADK activity. Green fluorescent protein-fusion based cellular localization experiments, carried out with the full-length At2g37250, suggested a plastidial localization for this isoform. In keeping with this observation, organelle isolation experiments revealed that the loss in ADK activity was confined to the inner plastid. This plastid stroma ADK gene was found to be expressed tissue constitutively but at much higher levels in illuminated leaves. Phenotypic and biochemical analyses of the mutant revealed that it exhibited higher amino acid biosynthetic activity in the light and was characterized by an enhanced root growth. When the mutant was subjected to either continuous light or continuous dark, growth phenotypes were also observed in the shoots. While the levels of adenylates were not much altered in the leaves, the pattern of change observed in the roots was consistent with the inhibition of an ATP-consuming reaction. Taken together, these data suggest a role for the plastid stromal ADK in the coordination of metabolism and growth, but imply that the exact importance of this isoform is tissue dependent.
Prospects for Change? Structural, Cultural and Action Dimensions of the Careers of Pioneer Women Priests in the Church of England
Authors: Bagilhole Barbara 
Published: December 2004

Like other organizations the Church of England has adapted to the greater and increasing involvement of women in paid work and other parts of the public domain. However, this has been a gradual, strongly contested and painful process for the Church. In 1986, it allowed women to enter the lowest rank of the clerical profession as deacons, and after many years of hard and bitter struggle the vote was won in the General Synod to ordain women to the priesthood.1 The first women priests were ordained in 1994. This article reports a study of 31 of the most senior and experienced Church of England women priests from dioceses across the whole of England.Women entering previously male‐dominated, or male exclusive occupations as in the case of the priesthood, are necessarily engaged in a process of change. The women priests in this study were active agents for change, they wanted to change the organization, both structurally and culturally. This article examines the question of whether these women ‘pioneers’ in the Church of England stand any chance of changing the organization and the occupation, or whether and to what extent they are changed themselves by needing to ‘fit in’. It will look at the structural and cultural factors, which may inhibit their agency or support it.
What's Special About Banks?
Authors: Benston George J. 
Published: December 2004

AbstractI delineate six aspects of how banks have been “special” (although not unique) and then consider whether and to what extent these attributes are still relevant. These include efficiently produced products, importance for the development and growth of economies, international scope, role in economic instability and the conduct of monetary policy, early regulation by governments, and source of data for academic researchers and institutions. Despite changes in the environment and in the ways in which financial services are provided, banks still are special. However, their specialness for public policy concerns is now limited to frauds and deposit insurance. I suggest ways in which these concerns can be dealt with efficiently.
When Are Commercial Loans Secured?
Authors: Gonas John S. , Highfield Michael J. , Mullineaux Donald J. 
Published: December 2004

AbstractWe analyze the factors that influence the decision to secure a commercial loan. We find evidence that variables reflecting adverse selection, moral hazard, and the prospects for default all affect the likelihood a loan will be collateralized. We find no evidence in favor of the predictions of certain theoretical models that high‐quality firms signal by providing collateral. Our results also show that lenders with less risk protection in the form of equity capital are more likely to require collateral, but that banks themselves are less likely to secure loans than nonbanks. Certain loan characteristics also influence the collateralization decision.
Stem cell transplantation for chronic lymphocytic leukaemia
Authors: Paneesha S. , Milligan D. W. 
Published: December 2004

SummaryEarly results of autologous stem cell transplantation (ASCT) in chronic lymphocytic leukaemia (CLL) suggested a significant proportion of patients remained disease‐free for years, raising the possibility of cure. More recent studies have shown no evidence of a plateau in the survival curves indicating that, at best, ASCT may only prolong disease‐free survival. Problems remain over progenitor cell mobilization and one study has raised anxieties about post‐transplant myelodysplasia. The impact of ASCT in CLL will only be properly ascertained in a randomized clinical trial and this in underway in Europe. Initial results of conventional allogeneic transplantation (allo‐SCT) were very disappointing, with an unacceptably high mortality, but did show that cure was possible in some patients. The introduction of reduced intensity conditioning has limited the early transplant‐related mortality but it remains too early to determine what proportion of patients will be cured. In view of these uncertainties, is important that reduced intensity allo‐SCT for CLL is conducted in the context of a clinical trial. Finally, CLL is very heterogeneous condition and great deal more is becoming understood about the prognostic factors. These will become important in allowing patients and their physicians a choice in balancing the risks of various treatment options.
Sensitivity of adult T‐cell leukaemia lymphoma cells to tumour necrosis factor‐related apoptosis‐inducing ligand
Authors: Hasegawa H. , Yamada Y. , Harasawa H. , Tsuji T. , Murata K. , Sugahara K. , Tsuruda K. , Ikeda S. , Imaizumi Y. , Tomonaga M. , Masuda M. , Takasu N. , Kamihira S. 
Published: December 2004

SummaryTumour necrosis factor (TNF)‐related apoptosis‐inducing ligand (TRAIL) induces apoptosis in many transformed cells, but not in normal cells, and hence TRAIL has recently emerged as a novel anti‐cancer agent. Adult T‐cell leukaemia lymphoma (ATLL) is a neoplasm of T‐lymphocyte origin aetiologically associated with human T‐lymphotropic virus type 1 (HTLV‐I), and is resistant to standard anti‐cancer therapy. We thus characterized the sensitivity of ATLL cells to TRAIL in this study. Although most primary ATLL cells and cell lines expressed TRAIL death receptors on their surface, they showed only restricted sensitivity to TRAIL. Among the 10 ATLL cell lines examined, one was sensitive, but two had insufficient death‐receptor expression, two had an unknown resistant mechanism with abrogation of the death signal upstream of caspase‐8, and the remaining five showed attenuation of the signal in both extrinsic and intrinsic pathways by X‐linked inhibitor of apoptosis and Bcl‐2/Bcl‐xL respectively. Furthermore, the level of HTLV‐I tax expression was significantly correlated to TRAIL resistance. Interestingly, ATLL cells themselves expressed TRAIL on the cell surface. Constitutive production of TRAIL may offer resistance, thus allowing the development of TRAIL‐resistant ATLL cells. Consequently, the resistant mechanism in ATLL cells against TRAIL was assigned to multiple factors and was not explained by a definitive single agent.
Increased AF1q gene expression in high‐risk myelodysplastic syndrome
Authors: Tse William , Joachim Deeg H. , Stirewalt Derek , Appelbaum Frederick R. , Radich Jerald , Gooley Theodore 
Published: December 2004

SummaryThe AF1q gene is expressed in normal haematopoietic progenitors, but less so in differentiated blood cells. In 47 patients with myelodysplastic syndrome (MDS), AF1q copy numbers were 0–6·8 × 106/μg RNA compared with 1·5–2·4 × 105/μg RNA in normal marrow. AF1q levels correlated with international prognostic scoring system (IPSS) scores (P = 0·004) and the risk of post‐transplant relapse (P = 0·05). Among IPSS high‐risk patients, survival correlated inversely with AF1q levels (P = 0·04). Thus, AF1q levels correlate with high‐risk MDS and may provide a marker for risk stratification.
The influence of Mimulus ringens floral display size on pollinator visitation patterns
Authors: Mitchell R. J. , Karron J. D. , Holmquist K. G. , Bell J. M. 
Published: December 2004

Summary

Pollinators visiting large floral displays may probe several flowers in sequence, leading to geitonogamous (among‐flower) self‐pollination. To investigate the relationship between floral display size and patterns of pollinator movement, we studied foraging by several pollinator species in four replicate arrays of Mimulus ringens (Scrophulariaceae). In each array displays were trimmed to two, four, eight and 16 flowers per plant.
Bees preferred large displays, and probed more flowers in sequence on large than on small displays. However, the proportion of available flowers probed decreased with display, resulting in nearly equal floral visitation rates across treatments.
Because pollinators probed more flowers in sequence on large displays, plants with numerous flowers should experience more geitonogamous self‐pollination than plants with small displays.
In all four treatments, pollinators frequently visited only one flower before leaving the plant. As the first flower probed on a plant cannot receive geitonogamous pollen, this potentially reduces selfing rates for those flowers, compared to flowers probed late in a long visitation sequence on a plant. Such differences among flowers in pollination history should increase variation in geitonogamous self‐pollination among fruits within plants.
The three most abundant pollinator species differed significantly in behaviours that could influence plant mating patterns, including number of flowers probed per plant; interplant movement distances; and grooming. Variation in foraging patterns was also evident among individuals within species. These subtle differences in response should affect the pollination services provided to plants.
Integrated plant temperature measurement using heat‐sensitive paint and colour image analysis
Authors: Smith W. K. , Brodersen C. R. , Hancock T. E. , Johnson D. M. 
Published: December 2004

Summary

Despite the fundamental importance of temperature to a variety of physiological processes, such as photosynthesis and transpiration in plants, accurately quantifying and integrating differences in surface temperatures is often difficult, if not impossible.
An inexpensive, user‐friendly technique is now available whereby plants and animals can be air‐brushed with a non‐toxic, heat‐sensitive paint that will generate six or more distinguishable colours across a temperature range of ≈5 °C and a resolution of <1 °C. These temperature‐indicating colours can then be photographed and evaluated quantitatively using image analysis software.
Compared to a more traditional temperature measurement technique (thermocouples), this method resulted in a mean surface temperature of up 5·1 °C warmer than the mean thermocouple temperature, as well as a computed 45% difference in transpirational water loss for a single leaf, multiple leaves on a shoot, and leaves within a crown.
Variation in rate of nectar production depends on floral display size: a pollinator manipulation hypothesis
Authors: Biernaskie J. M. , Cartar R. V. 
Published: December 2004

Summary

Pollinators typically visit more flowers on plants with larger floral displays, which should present such attractive plants with significant pollen transport losses.
Many‐flowered plants with hermaphrodite flowers might reduce the costs of attractiveness by encouraging fewer sequential flower visits by pollinators. One mechanism that accomplishes this is to produce variable nectar rewards, which will cause risk‐averse foragers to leave the plant after visiting fewer flowers.
We test the prediction that within‐plant variability in nectar production rate increases with the relative number of open flowers on a plant. A field survey of nine herbaceous angiosperm species native to Alberta, Canada revealed a significant positive correlation between nectar variability (measured as standard deviation) and the size of the floral display within species. This relationship existed over and above the null expectation of a positive correlation between mean and SD.
Our results suggest that multiflowered plants might maximize the male fitness returns associated with a plant's attraction status (determined by relative display size), by taking advantage of risk‐averse foraging by their pollinators.
Sub‐basalt decoupled walkaway VSP imaging
Authors: Droujinine Alexander 
Published: December 2004

ABSTRACTWalkaway vertical seismic profile (VSP) data acquired in basalt‐covered areas can be used to improve knowledge of the sub‐basalt structure. A synthetic example and a case study from the North Atlantic (UK) show that elastic two‐way downward‐continuation migration combined with the stationary‐phase principle is well suited to the processing of VSP data. Vector data are processed using decoupled elastic migration algorithms in both isotropic and anisotropic media. To illustrate the value of decoupled imaging equations, conventional PP imaging is carried out on the enhanced VSP data and compared with the decoupled scheme. Decoupled vector migration operates directly on the displacement vector, and uses various wave modes. Downgoing waves are migrated to image basalt lava flows and measure their anisotropy. Upgoing waves are used for high‐resolution sub‐basalt imaging.
Residual dip moveout in VTI media
Authors: Alkhalifah Tariq , De Hoop Maarten V. 
Published: December 2004

ABSTRACTDip‐moveout (DMO) correction is often applied to common‐offset sections of seismic data using a homogeneous isotropic medium assumption, which results in a fast execution. Velocity‐residual DMO is developed to correct for the medium‐treatment limitation of the fast DMO. For reasonable‐sized velocity perturbations, the residual DMO operator is small, and thus is an efficient means of applying a conventional Kirchhoff approach. However, the shape of the residual DMO operator is complicated and may form caustics. We use the Fourier domain for the operator development part of the residual DMO, while performing the convolution with common‐offset data in the space–time domain. Since the application is based on an integral (Kirchhoff) method, this residual DMO preserves all the flexibility features of an integral DMO. An application to synthetic and real data demonstrates effectiveness of the velocity‐residual DMO in data processing and velocity analysis.
Climate change and cereal aphids: the relative effects of increasing CO2 and temperature on aphid population dynamics
Authors: Newman Jonathan A. 
Published: December 2004

AbstractExperimental evidence regarding the responses of cereal aphids to rising atmospheric CO2 has been ambiguous. Some studies suggest increased population sizes under future CO2 levels, others suggest decreased population sizes, and still others suggest little or no difference. Recently, Newman et al. (2003) constructed a general mathematical model of the aphid–grass interaction to investigate whether or not we should, in fact, expect a general aphid response to rising CO2. They concluded that aphid populations are likely to be larger under future CO2 concentrations if soil N levels are high, the aphid species' nitrogen requirement is low and the aphid species' density‐dependent response in winged morph production is weak. In that model, and in field experiments, CO2 concentration influences aphid population dynamics through the effect it has on plant quality. However, future CO2 concentrations are also likely to be accompanied by higher ambient temperatures, a combination that has received little focus to date. In the present paper, the Newman et al. model is used to consider the combined effects of increased CO2 concentrations and temperature on aphid population sizes. It is concluded that, when both factors are elevated, aphid population dynamics will be more similar to current ambient conditions than expected from the results of experiments studying either factor alone. This result has important implications for future experimentation.
Common birds facing global changes: what makes a species at risk?
Authors: Julliard Romain , Jiguet Frédéric , Couvet Denis 
Published: December 2004

AbstractClimate change, habitat degradation, and direct exploitation are thought to threaten biodiversity. But what makes some species more sensitive to global change than others? Approaches to this question have relied on comparing the fate of contrasting groups of species. However, if some ecological parameter affects the fate of species faced with global change, species response should vary smoothly along the parameter gradient. Thus, grouping species into few, often two, discrete classes weakens the approach. Using data from the common breeding bird survey in France – a large set of species with much variability with respect to the variables considered – we show that a quantitative measure of habitat specialization and of latitudinal distribution both predict recent 13 year trends of population abundance among 77 terrestrial species: the more northerly distributed and the more specialized a species is, the sharper its decline. On the other hand, neither hunting status, migrating strategy nor body mass predicted population growth rate variation among common bird species. Overall, these results are qualitatively very similar to the equivalent relationships found among the British butterfly populations. This constitutes additional evidence that biodiversity in Western Europe is under the double negative influence of climate change and land use change.
Differential effects of elevated CO2 on acorn density, weight, germination, and predation among three oak species in a scrub‐oak forest
Authors: Stiling Peter , Moon Daniel , Hymus Graham , Drake Bert 
Published: December 2004

AbstractMuch research on the effects of elevated CO2 on forest trees has focused on quantitative changes in photosynthesis, secondary chemistry, and plant biomass. However, plant fitness responses to rising CO2 should also include quantitative measures of reproduction, since most forest systems are recruitment limited. Until now, it has proved very difficult to grow forest trees to sexual maturity in a CO2‐enriched environment. This paper is the first of its kind to address the effects of elevated CO2 on the reproduction of hardwood trees in a natural forest. Beginning in 1996, scrub‐oak vegetation, predominantly three species of scrub‐oaks, Quercus myrtifolia, Q. chapmanii, and Q. geminata, were grown inside eight chambers with elevated CO2 (704 parts per million (ppm)) and eight with ambient CO2 (379 ppm) at Kennedy Space Center, Florida. In elevated CO2, acorn production increased significantly for the dominant species Q. myrtifolia and for Q. chapmanii, but it did not increase for the subdominant, Q. geminata. Acorn weight, germination rate, and predation by weevils were unaffected by CO2. Thus, recruitment of some forest tree species into the Florida scrub‐oak community is likely to be accelerated in an atmosphere of increased CO2. However, because the acceleration of recruitment differs among species, over the long term, Q. myrtifolia and Q. chapmanii will be favored over Q. geminata and this is likely to change patterns of species diversity.
Simulated chronic NO3− deposition reduces soil respiration in northern hardwood forests
Authors: Burton Andrew J. , Pregitzer Kurt S. , Crawford Jeffrey N. , Zogg Gregory P. , Zak Donald R. 
Published: December 2004

AbstractChronic N additions to forest ecosystems can enhance soil N availability, potentially leading to reduced C allocation to root systems. This in turn could decrease soil CO2 efflux. We measured soil respiration during the first, fifth, sixth and eighth years of simulated atmospheric NO3− deposition (3 g N m−2 yr−1) to four sugar maple‐dominated northern hardwood forests in Michigan to assess these possibilities. During the first year, soil respiration rates were slightly, but not significantly, higher in the NO3−‐amended plots. In all subsequent measurement years, soil respiration rates from NO3−‐amended soils were significantly depressed. Soil temperature and soil matric potential were measured concurrently with soil respiration and used to develop regression relationships for predicting soil respiration rates. Estimates of growing season and annual soil CO2 efflux made using these relationships indicate that these C fluxes were depressed by 15% in the eighth year of chronic NO3− additions. The decrease in soil respiration was not due to reduced C allocation to roots, as root respiration rates, root biomass, and root turnover were not significantly affected by N additions. Aboveground litter also was unchanged by the 8 years of treatment. Of the remaining potential causes for the decline in soil CO2 efflux, reduced microbial respiration appears to be the most likely possibility. Documented reductions in microbial biomass and the activities of extracellular enzymes used for litter degradation on the NO3−‐amended plots are consistent with this explanation.
Uncertainty analysis of soil organic carbon stock change in Canadian cropland from 1991 to 2001
Authors: VandenBygaart A. J. , Gregorich E. G. , Angers D. A. , Stoklas U. F. 
Published: December 2004

AbstractNational estimates of changes in the amount of soil organic carbon (SOC) in cropland requires an assessment of uncertainty for accounting and reporting under the United Nations Framework Convention on Climate Change (UNFCCC) and the Kyoto Protocol. Canada has data sets on SOC stocks in croplands, historical changes in SOC levels due to management practices, and historical changes in the area of land devoted to certain soil management practices. We conducted an analysis of uncertainty of the change in SOC levels due to management practices in Canada from 1991 to 2001 using Monte Carlo analysis and a simple model. Probability distribution functions were determined for each of the inputs of the model, enabling us to assess the uncertainty for the output. The storage rate of SOC in cropland soils of Canada for the 10‐year period ranged from 3.2 to 8.3 Mt C yr−1 at 95% confidence, with a mean of 5.7 Mt C yr−1. Approximately 67% (about 3.8 Mt C yr−1) of the increase in SOC storage in Canada occurred in Saskatchewan where the cropland area under no‐till increased from 10% to 35%, and the area of summer‐fallow declined from 43% to 20% during the study period. The large uncertainty in the effect of no‐till on SOC stock changes in the Gray‐Brown Luvisols of Ontario contributed most to the variance in the model output. If trends in agricultural management continue for the next 10‐year census period, the estimated SOC storage would comprise between 7% and 19% of the gap required to achieve the 6% reduction in 1990 greenhouse gas emission levels for Canada under the Kyoto Protocol.