bluuebunny/crossref_metadata_2025_split huggingface dataset:
The importance of weather and agronomic factors for the overwinter survival of yellow rust (Puccinia striiformis) and subsequent disease risk in commercial wheat crops in England
Authors: Gladders P. , Langton S.D. , Barrie I.A. , Hardwick N.V. , Taylor M.C. , Paveley N.D. 
Published: May 2007

AbstractDisease survey data from 4475 randomly selected crops of wheat from England and Wales during 1985–2000 showed that yellow rust was most prevalent in 1988, 1989, 1990, 1998 and 1999. Disease severity on the upper two leaves was low as >95% crops had received foliar fungicides. Factors affecting the presence or absence (incidence) of yellow rust were investigated using random effects logistic regression (general linear mixed model). This enabled crop management (risk) variables for individual crops to be combined with meteorological variables measured at the county level. Two models are presented that analysed the effect of host genotype on incidence either solely through yellow rust resistance rating (Model 1) or by including both resistance rating (fixed effect) and cultivar (fitted as a random term) (Model 2). In both models, the percentage of crops with yellow rust decreased with cultivar disease resistance ratings ≥3, the occurrence of severe frosts (<−5°C), use of systemic seed treatment and application of foliar fungicide sprays. There were no significant effects (P < 0.05) of timing of fungicide sprays, previous cropping or summer weather. The use of risk variables associated with overwintering survival may help adjust fungicide inputs to seasonal risk.
Germination ecology of invasive alien Anthemis cotula helps it synchronise its successful recruitment with favourable habitat conditions
Authors: Rashid I. , Reshi Z. , Allaie R. R. , Wafai B. A. 
Published: May 2007

Abstract Anthemis cotula is a widespread invasive alien species in Kashmir Himalaya. Being a winter annual, the species reproduces entirely by achenes and synchrony between germination requirements of the species and the habitat conditions must be of critical importance in its invasiveness. To examine how the achenes of different ages respond to different environmental cues, two laboratory experiments were performed wherein effects of different nitrogen applications and growth hormones under continuous light and dark conditions were explored. Results show that the achenes are positively photoblastic and have requirement for after‐ripening. Nitrogen applied either as potassium nitrate or as thiourea significantly improved achene germination both under continuous light and dark conditions. Although kinetin (6‐furfurylaminopurine) did not influence achene germination, gibberellic acid (GA3) applied at 1.0 mM concentration had the most significant effect on the final percentage germination under both light and dark conditions. These results suggest that the achenes have an elaborate mechanism of sensing the habitat conditions that helps them to synchronise their germination with favourable environmental conditions – a strategy that aids the species in ensuring recruitment, survival and its spread in Kashmir Himalaya.
Nectar Production of Calliandra longipedicellata (Fabaceae: Mimosoideae), an Endemic Mexican Shrub with Multiple Potential Pollinators
Authors: Hernández‐Conrique David , Ornelas Juan Francisco , García‐Franco José G. , Vargas C. Fabián 
Published: May 2007

ABSTRACTThe nectar resource environment across which nectarivores forage may be patchy and variable. To understand the sources and consequences of such a variation, nectar production was investigated in Calliandra longipedicellata. Nectar was measured once a month throughout a 3‐mo winter season in two successive years at three sites. We also conducted diurnal and nocturnal field observations to describe visitation rates of floral visitors, and a pollinator exclusion experiment to evaluate diurnal and nocturnal pollination at the three sites. In all populations, nectar secretion was primarily nocturnal, although flowers produced some nectar during the day. Sugar production per flower varied significantly at both the seasonal and population levels, although nectar production rates and a well‐defined afternoon to morning production pattern were consistent across months, populations, and years. Average nectar production rates were high compared to other Calliandra species, and to most hummingbird‐ or hawkmoth‐pollinated plants in the region. Flowers were regularly visited by hawkmoths, bats, hummingbirds and various diurnal insects, and all populations had similar rates of visitation. Nocturnal insects had the highest overall visitation rates (three times as high as those by diurnal insects). Fruit production varied among pollination treatments and populations, and significant differences were found in fruit production when flowers exposed to both diurnal and nocturnal visitation were compared to flowers exposed only to diurnal visitation. Our results and the bright‐red staminal filaments of C. longipedicellata indicate lack of specialization for particular pollinators.
Saproflorivory: A Diverse Insect Community in Fallen Flowers of Lecythidaceae in French Guiana
Authors: Feinstein Julie , Mori Scott , Berkov Amy 
Published: May 2007

ABSTRACTWe investigated insects associated with flowerfalls from seven tree species belonging to the Brazil nut family (Lecythidaceae) in the lowland rain forest of French Guiana. Freshly fallen androecia were collected from the forest floor and incubated in rearing chambers. Over 1300 insects representing 21 families were collected from the caged flowers, including abundant Diptera and Coleoptera, five moth morphospecies and four species of lycaenid butterflies. These insects feed on androecia. We also documented the presence of predators and parasitoids, indicating an additional trophic level.
The Use of Seeds by a Twig‐Dwelling Ant on the Floor of a Tropical Rain Forest
Authors: Pizo Marco Aurélio 
Published: May 2007

ABSTRACTThe role of Pheidole praeses, a twig‐nesting ant inhabiting the floor of the Brazilian Atlantic forest, as potential secondary seed disperser was investigated. A total of 901 seeds (20 morphospecies) were retrieved from 50 nests, most of them intact and able to germinate. Considering the abundance of Pheidole species and the evidence pointing to their potential as seed dispersers, these ants may be important determinants of the recruitment of small‐seeded plants in tropical forests.Abstract in Portugese is available at http://www.blackwell‐synergy.com/loi/btp.
Impact of Coastal Land Reclamation on Ground Water Level and the Sea Water Interface
Authors: Guo Haipeng , Jiao Jiu Jimmy 
Published: May 2007

AbstractLand reclamation in coastal areas may have a significant effect on local ground water systems. Steady‐state analytic solutions based on Dupuit and Ghyben‐Herzberg assumptions are derived to evaluate this effect. Two situations are considered, both with ground water flow resulting from precipitation recharge: the coastal aquifer of an extensive landmass and an island. The results show that after reclamation, the water table rises and the salt water‐fresh water interface moves seaward. The degree of these changes depends on the extent of reclamation and the hydraulic conductivity of the fill material. For the island situation, the reclamation displaces the ground water divide and changes the ground water conditions in the entire island. An unintended advantage of the reclamation is an increase of fresh ground water resource because the reclaimed land can be an additional aquifer and rain recharge takes place over a larger area.
Hydrologic Significance of Carbon Monoxide Concentrations in Ground Water
Authors: Chapelle Francis H. , Bradley Paul M. 
Published: May 2007

AbstractDissolved carbon monoxide (CO) is present in ground water produced from a variety of aquifer systems at concentrations ranging from 0.2 to 20 nanomoles per liter (0.0056 to 0.56 μg/L). In two shallow aquifers, one an unconsolidated coastal plain aquifer in Kings Bay, Georgia, and the other a fractured‐bedrock aquifer in West Trenton, New Jersey, long‐term monitoring showed that CO concentrations varied over time by as much as a factor of 10. Field and laboratory evidence suggests that the delivery of dissolved oxygen to the soil zone and underlying aquifers by periodic recharge events stimulates oxic metabolism and produces transiently high CO concentrations. In between recharge events, the aquifers become anoxic and more substrate limited, CO is consumed as a carbon source, and CO concentrations decrease. According to this model, CO concentrations provide a transient record of oxic metabolism affecting ground water systems after dissolved oxygen has been fully consumed. Because the delivery of oxygen affects the fate and transport of natural and anthropogenic contaminants in ground water, CO concentration changes may be useful for identifying predominantly anoxic ground water systems subject to periodic oxic or microaerophilic conditions.
Comparison of Flowpaths to a Well and Spring in a Karst Aquifer
Authors: Toran Laura , Herman Ellen K. , White William B. 
Published: May 2007

AbstractThe permeability of some karst aquifers consists of networks of poorly integrated conduits and dissolution‐widened fractures. The flow includes conduit flow, especially during storm recharge, but lacks the focused recharge into single master conduits that occurs in more highly developed karst systems. The proportions of conduit and dispersed flow are difficult to quantify in such systems. This study examines the flowpaths in a small karst watershed, based on comparing the physical and chemical response to storm flow at both a spring and a well. By conducting continuous monitoring at both locations, a better understanding of the flowpaths in a poorly integrated network was obtained. A more permeable flowpath to the spring leads to faster storm response and lower ion concentrations. The flowpath to and from the well is more complicated. The higher ion content and slower storm response suggest slower, more dispersed flowpaths. However, the well has greater variation in ion chemistry. Periodic recharge may dilute well concentrations due to faster (conduit or fracture) flowpaths. Although karst systems such as this are difficult to characterize, applying a variety of geochemical and physical monitoring techniques at multiple locations illustrates that the flowpaths can vary in both space and time.
Extinction Depth and Evapotranspiration from Ground Water under Selected Land Covers
Authors: Shah Nirjhar , Nachabe Mahmood , Ross Mark 
Published: May 2007

AbstractIn many landscapes, vegetation extracts water from both the unsaturated and the saturated zones. The partitioning of evapotranspiration (ET) into vadose zone evapotranspiration and ground water evapotranspiration (GWET) is complex because it depends on land cover and subsurface characteristics. Traditionally, the GWET fraction is assumed to decay with increasing depth to the water table (DTWT), attaining a value of 0 at what is termed the extinction depth. A simple assumption of linear decay with depth is often used but has never been rigorously examined using unsaturated‐saturated flow simulations. Furthermore, it is not well understood how to relate extinction depths to characteristics of land cover and soil texture. In this work, variable saturation flow theory is used to simulate GWET for three land covers and a range of soil properties under drying soil conditions. For a water table within half a meter of the land surface, nearly all ET is extracted from ground water due to the close hydraulic connection between the unsaturated and the saturated zones. For deep‐rooted vegetation, the decoupling of ground water and vadose zone was found to begin at water table depths between 30 and 100 cm, depending on the soil texture. The decline of ET with DTWT is better simulated by an exponential decay function than the commonly used linear decay. A comparison with field data is consistent with the findings of this study. Tables are provided to vary the extinction depth for heterogeneous landscapes with different vegetation cover and soil properties.
Using UCODE_2005 and PHREEQC To Determine Thermodynamic Constants from Experimental Data
Authors: Skold Magnus E. , Thyne Geoffrey D. , McCray John E. 
Published: May 2007

AbstractThis article presents a method for estimating chemical thermodynamic constants from experimental data using the two computer programs UCODE_2005 and PHREEQC. As an example, the conditional stability constant for lead (Pb) complexation by a remediation agent (carboxymethyl‐β‐cyclodextrin) is estimated, but the method can be applied to estimate other thermodynamic parameters such as sorption constants and degradation rate constants. Advantages of this technique include estimation of uncertainties associated with estimated parameters, evaluation of information content of observations, statistical evaluation of the appropriateness of the conceptual model, and statistical‐based comparison of different models.
Carbon Sequestration in Agriculture: EU and US Perspectives La séquestration du carbone en agriculture: perspectives pour l'Europe et les Etats Unis CO2‐Sequestrierung in der Landwirtschaft: Perspektiven für die EU und die USA
Authors: Young Linda M. , Weersink Alfons , Fulton Murray , Deaton B. James 
Published: May 2007

summaryCarbon Sequestration in Agriculture: EU and US PerspectivesBoth the European Union and the United States are defining the role that agricultural soil sequestration of carbon will play in their overall strategies to reduce greenhouse gas emissions. These decisions have important ramifications, as recent research indicates that soil sequestration of carbon may have the potential to reduce the need for reductions in greenhouse gas emissions. The EU ratified the Kyoto Protocol in 2002, but chose not to use soil sequestration of carbon in its strategy to address climate change, and has excluded it from the EU's new carbon market. The EU's strategy can be explained by uncertainties surrounding soil sequestration and by the importance of its international leadership on climate change. In contrast, the United States has not ratified the KP, but is encouraging the use of soil carbon sequestration on a modest level, through its agricultural policy and research. There is some trading taking place using soil sequestration in the weak US market for carbon, partially due to US freedom from international protocols on this method of greenhouse gas reduction. As both the science and international protocols for carbon sequestration advance, the EU may reconsider the use of agricultural sequestration of carbon as a means for achieving its Kyoto Protocol commitments.
Rural Development Group Politics: A Hidden Cost? Des coûts cachés dans l'économie politique des groupes de développement rural? Die Gruppenpolitik zur Entwicklung des ländlichen Raums: Versteckte Kosten?
Authors: McAreavey Ruth 
Published: May 2007

summaryRural Development Group Politics: A Hidden Cost?I challenge the popular notion of European rural development group dynamics and argue for a better understanding of the role of micro‐politics as a means of enhancing the performance of these groups. The views are research based and have relevance to the broader rural development and regeneration sector. Micro‐politics involves knowledge, power, trust, perceptions, understanding, social networks, values and traits that arise as a result of individuals interacting within a group whilst working on a shared goal, such as rural development. The monetary and time costs to a community of failing to address micro‐politics and nurture positive group relations are considerable. These include time spent in unproductive meetings and poorly prioritized—and ultimately unsuccessful—funding applications as a result of failure to agree priorities. Successful groups rely on individuals interacting in a way that achieves a greater social good. Mutual trust amongst the actors lies at the heart of effective group activity. Effective management of micro‐politics requires steps to nurture a culture of mutual trust to ensure that rural development actors co‐operate rather than play destructive games with one another. A case study example of a relatively straightforward approach illustrates how this might be done in practice.
Non‐metallic grid for radiographic measurement
Authors: Krithika Arumbakkam C. , Kandaswamy Deivanayagam , Velmurugan Natanasabapathy , Krishna Velayudham Gopi 
Published: May 2007

AbstractThe purpose of this paper is to suggest an easier, non‐metallic radiographic grid system for measuring the working length and radiographic size of pathologic areas during endodontic diagnosis and prognosis determination.
Anti-oxidative systems in rat skeletal muscle after acute physical exercise
Authors: Bachur José Alexandre , Garcia Sérgio Britto , Vannucchi Hélio , Jordao Alceu Afonso , Chiarello Paula Garcia , Zucoloto Sérgio 
Published: May 2007

The objective of this study was to analyze the oxidative stress of skeletal muscle of sedentary rats at the morphological and biochemical level, due to acute physical effort performed at different intensities and during different periods of time. Forty-two male sedentary Wistar rats were divided into two groups, group A (swimming for 50 min) and group B (swimming for 100 min), which were further subdivided into 3 different exercise intensities, non-weight bearing (subgroup I), 3% weight load (subgroup II), and 5% weighted load (subgroup III), as well as a control-rested group (C). The animals were killed by ether inhalation and fragments of the gastrocnemius muscle were removed for the determination of malondialdehyde (MDA), reduced glutathione (GSH), and vitamin E concentrations. When all groups were compared with the control-rested group (C), gastrocnemius MDA levels at 50 and 100 min were higher at all swimming intensities. GSH consumption was greater at all intensities in group A, and only at 100 min in group BI; vitamin E consumption was significantly higher only in groups BII and BIII. When groups were compared by intensity at each swimming time there were no differences between I, II, and III at 50 min for any of the substances analyzed (MDA, GSH, and vitamin E), but at 100 min opposite effects were observed for GSH and vitamin E, with vitamin E consumption and GSH recovery occurring with increasing weight load. Higher concentrations of skeletal muscle MDA could indicate elevated lipid peroxidation at each time and exercise intensity, with highest MDA levels observed after the longest exercise duration and at the highest intensity. The layer-line mode of utilization of body antioxidants could explain the concentrations of GSH and vitamin E: first the use of GSH, even with minor oxidative stress, and then vitamin E consumption only in the presence of greater and more prolonged oxidative stress, indicating the necessity of adequate body levels of both antioxidants for proper utilization by the body antioxidant defense system.
Iron supplementation during pregnancy: what are the risks and benefits of current practices?
Authors: Rioux France M. , LeBlanc Caroline P. 
Published: May 2007

Iron-deficiency anemia is still prevalent among pregnant women living in industrialized countries such as Canada. To prevent this deficiency, iron supplements (30 mg/d) are routinely prescribed to Canadian pregnant women. Recently, dietary reference intakes for iron have increased from 18 and 23 mg/d during the second and third trimesters, respectively, to 27 mg/d throughout the pregnancy for all age groups. Whether this new recommendation implies an increase of iron dosage in supplements has not been answered. Are there any benefits or risks for the mother and her infant associated with iron supplementation during pregnancy? If iron supplementation is recommended, what should be the ideal dosage? This article reviews current knowledge on the potential negative or positive impact of iron supplementation during pregnancy on the outcomes of both infants and mothers. Based on the literature reviewed, a low daily dose of iron (30 mg elemental iron) during pregnancy improves women’s iron status and seems to protect their infants from iron-deficiency anemia. Several studies have also shown that a low daily dose of iron may improve birth weight even in non-anemic pregnant women. However, higher dosages are not recommended because of the potential negative effects on mineral absorption, oxidative pathways, and adverse gastrointestinal symptoms. To date, it is still not clear if health professionals should recommend routine or selective supplementation. However, neither routine nor selective iron supplementation during pregnancy is able to eliminate iron-deficiency anemia. Even though the dietary reference intake for iron during pregnancy has been recently increased, we do not recommend higher doses of iron in supplements designed for pregnant women.
Nuclear Microprobe and Micro-PIXE Analysis of Thick Target: Program and Its Applications
Authors: DAI Zhongning , Ren Chaigang , Yang Fujia 
Published: May 2007

PIXE (Particle Induced X-ray Emission), mainly Proton Induced X-ray Emission, has been developed into a well established technique for elemental analysis, especially for trace elemental analysis down to ppm or even ppb level. Nuclear Microprobe is a quickly developing technique around the world for 2 dimensional or even 3 dimensional element analysis if several nuclear analytical techniques, such as Rutherford backscattering spectrometry (RBS) can be available at the same time. The present resolution of NMP can be down to less than 1μm. To thick target analysis, i.e., the energy loss effect and the consequent X-ray cross section Change with the depth can not be neglected, therefore we have to consider the process of particle interactions with atoms in detail. In this article, NMP (Nuclear Micro-Probe) and micro-PIXE analysis of thick target, which are mainly involved into the process of ions interaction with atoms, are reviewed on the basis of work what we have done at Fudan University. The software package TSPIXE (PIXE analysis of Thick Sample), which includes different versions for different applications, developed at Fudan University for quantitative analysis of thick target and simulation of PIXE and micro-PIXE spectra are described and its performance is demonstrated too. The TSPIXE package, which includes TSPIXE version I, version II, version III and TSμPIXE, was written in FORTRAN and C computer language and can be run at PC computer under MSDOS or WINDOWS environment. From the different demonstrations and applications we can see the package is very useful to quantitative analysis of thick samples and to understand the relationships between elemental X-ray intensity distributions and concentration distributions, sample structure, beam size and etc.