bluuebunny/crossref_metadata_2025_split huggingface dataset:
Multiple‐scale soil moisture distribution and its implications for ecosystem restoration in an arid river valley, China
Authors: Ma K.‐M. , Fu B.‐J. , Liu S.‐L. , Guan W.‐B. , Liu G.‐H. , Lü Y.‐H. , Anand M. 
Published: January 2004

AbstractThe spatial distribution of soil moisture and its multiple‐scale correlations to other environmental factors were examined along the Upper Minjiang River valley, China, a landscape subject to severe land degradation of soil and water erosion but also under investigation for potential ecosystem restoration. Results showed that: (1) Soil moisture was highest in the headwaters, and lowest in the arid valley, while moderate values characterized outside the arid valley. The polynomial model of soil moisture distribution on slopes was concave in the lightly disturbed headwaters, convex in the highly damaged arid valley, while convex on south facing slopes and concave on north facing slopes in highly damaged areas in better environmental condition. (2) Soil moisture was correlated with environmental factors at different scales, where elevation and air humidity were only correlated at the sample plot scale, light intensity and wind speed were found to be significant at both slope and site scales and slope and sample plot scales; while slope angle was correlated at all the three scales. From this we conclude that it is possible to improve soil moisture conditions in the arid valley by lowering slope angle and adding low‐cost irrigation systems. (3) The practical threshold of soil moisture for growing meadows, shrubs, and forests were 11ċ800 per cent, 3ċ925 per cent, and 16ċ078 per cent respectively; the arid valley displayed soil‐moisture conditions unfavourable to forest growth. The planned reforestation project is not ecologically reasonable. Reducing human disturbance and revegetating with natural shrubs and meadows may produce more effective results. Copyright © 2004 John Wiley & Sons, Ltd.
The development of sustainable earthworm populations at Calvert landfill site, UK
Authors: Butt K. R. , Lowe C. N. , Frederickson J. , Moffat A. J. 
Published: January 2004

AbstractEarthwormsAllolobophora chloroticaandAporrectodea longawere inoculated into Calvert landfill site in spring 1992, in conjunction with the planting of two tree speciesAlnus glutinosaandAcer pseudoplatanus. Monitoring has taken place over a period of 11 years. Sampling in 2003 revealed that earthworm distribution no longer equated to the inoculation treatments; the worms had spread extensively. The presence ofA. glutinosahad a significant effect (p<0ċ01) on earthworm number (mean density 198 m−2) and biomass (34 g m−2) compared to plots whereA. pseudoplatanushad been planted and subsequently died (mean density 118 m−2; biomass 21 g m−2). Results suggest that tree presence may be critical to earthworm community development.In 2002, the spread ofA. chloroticafrom the original points of inoculation had reached 60 m with the highest recorded population density at 108 m−2with a mass of 18ċ6 g m−2.A. longawas recorded at a distance of 132 m from the nearest point of inoculation with the highest recorded population density at 70 m−2with a mass of 49ċ3 g m−2, 10 m from the original inoculation grid. Other species recorded (and % of total) wereAporrectodea rosea(0ċ9)Lumbricus castaneus(7ċ4),Eiseniella tetraedra(21ċ5) andLumbricus rubellus(4ċ5). The two inoculated species,A. chlorotica(40ċ4) andA. longa(25ċ3), accounted for two thirds of the earthworms found on site. The highest earthworm community density was 213 m−2with a mass of 73ċ9 g m−2at 10 m from original point of inoculation.In 1999, treatments of surface organic matter (OM), in the form of composted green waste, and rotavation were applied to non‐replicated plots of 50 m2with the effects on earthworm distribution and abundance recorded in 2002. Addition of OM alone led to an increase in number and mass (331 m−2; 95 g m−2) compared to the control (233 m−2; 51 g m−2), while rotavation alone (111 m−2; 36 g m−2) had a detrimental effect over the given time period.This long‐term monitoring programme has demonstrated the development of sustainable earthworm communities on a landfill site. Natural nutrient accumulation and addition of OM on or into the soil‐forming material appeared to assist this process. This work may help to inform post‐capping treatment at similar landfill sites Copyright © 2004 John Wiley & Sons, Ltd.
Evaluation of alternative approaches to rainforest restoration on abandoned pasturelands in tropical North Queensland, Australia
Authors: Florentine S. K. , Westbrooke M. E. 
Published: January 2004

AbstractThe lag time for natural recruitment of tropical rainforest species in abandoned pastureland is very long, therefore artificial restoration techniques have been employed to accelerate natural seedling recruitment. The objectives of this study were to investigate: (1) the success/failure of establishment 502 seedlings belonging to 15 species from 11 families planted approximately ten years ago; and (2) the influence of different restoration techniques on enhancing natural recruitment during this period. The study was conducted in the wet tropical rainforest region of northeast Queensland, Australia as a completely randomized block design involving five treatments with two replicates. In each plot, 63 tropical rainforest seedlings from one or a combination of species were planted randomly. Two control plots were laid out where no seedlings were planted. Survival, height and diameter data were taken on the seedlings ten years after planting. Each 11×17 m2 plot was further divided into 187, 1×1 m2 subplots. Within each subplot all seedlings recruited were located and identified. Canopy cover was estimated using belt transects 1 m apart that ran in an east–west direction across the plots. Within each plot the percentage of grass, and the crown cover were estimated using the Braun‐Blanquet cover abundance scale. Survival rate of planted seedlings varied across the treatment plots. The survival rate ranged from 65 to 75 per cent for primary‐promoter species, 85 to 100 per cent in middle‐phase species and 42 to 57 per cent for mature‐phase species. No Pilidiostigma tropicum seedlings survived in any treatment. Fourteen species recruited naturally across the treatment plots. A total of 410 seedlings were naturally recruited from 11 different families in the ten‐year‐old reforested site. The highest natural recruitment (236 seedlings) occurred in Treatment 3, where Omalanthus novo‐guineensis seedlings were planted with eight primary‐promoter species, followed by 99 in Treatment 5 where a group of primary‐promoters, middle phase species and mature‐phase species were planted together, 36 in Treatment 4 (Alphitonia petriei planted with eight primary‐promoter species), 10 in Treatment 2 where only Omalanthus novo‐guineensis seedlings were planted, and 13 in control plots. Grass cover declined with increasing species diversity and increased canopy cover. The results indicate that the diversity of species used in restoration had a major influence on natural recruitment. Copyright © 2004 John Wiley & Sons, Ltd.
Wheat field erosion rates and channel bottom sediment sources in an intensively cropped northeastern Oregon drainage basin
Authors: Nagle G. N. , Ritchie J. C. 
Published: January 2004

AbstractSediment tracers were used to quantify erosion from cultivated fields and identify major source areas of channel bottom sediment within the Wildhorse Creek drainage, an intensively cropped tributary of the Umatilla River in northeastern Oregon, USA. Available data indicated that Wildhorse Creek was one of the largest sediment yielding tributaries of the Umatilla River. Carbon, nitrogen and the nuclear bomb‐derived radionuclide 137Cs were used as tracers to fingerprint sediment sources. Sediment was collected from the stream bottom and active floodplain and compared to samples from cultivated fields and channel banks. Samples were characterized on the basis of tracer concentrations and a simple mixing model was used to estimate the relative portion of bottom sediment derived from cultivated surface and channel banks. The results indicate that the amount of bottom sediment derived from cultivated surface sources was less than 26 per cent for the 1998 winter season, although this estimate has a high margin of error. Cesium‐137 was also used to estimate surface erosion from three cultivated fields in the watershed. Annual estimates of erosion since 1963 from the three sampled fields were from 3 to 7ċ5 t ha−1 yr−1. For the 1998 season, it appears that most channel‐bottom sediment was of subsurface origin with much of it likely coming from channel and gully banks indicating that significant reductions in sediment in Wildhorse Creek might be accomplished by the stabilization of eroding riparian areas and swales on the lower slopes of agricultural fields. Published in 2004 by John Wiley & Sons, Ltd.
A decision support system for soil and water conservation measures on agricultural watersheds
Authors: Sarangi A. , Madramootoo C. A. , Cox C. 
Published: January 2004

AbstractIntegrated watershed management (IWM) is vital in achieving agricultural sustainability in terms of both production and environmental protection. A decision support system (DSS) is useful in generating alternative decision scenarios for management of natural resources, facilitating the implementation of IWM concepts in an interactive and holistic way. The decision to implement an appropriate land use coupled with suitable soil and water conservation techniques not only enhances watershed health but also prevents sediment losses. Besides reducing basin fertility, such losses decrease the storage capacity of downstream reservoirs through silt deposition, which can, in turn, give rise to low biomass production and poorer flood control. In order to facilitate IWM, an effort was made to develop, in the Visual Basic programming language, a soil and water conservation DSS which considered both structural and cropping practices for arresting sediment loss. Input parameters to the DSS for a given tract of land included: mean slope; sediment loss; soil type; and land capability class (LCC). Outputs included decision criteria to choose among alternative structural measures and suggested cropping systems to serve as biological measures to reduce soil loss and conserve water. Structural watershed management measures included a variety of soil and water conservation structures widely adopted by farming communities throughout the world. The DSS is capable of providing sediment control solutions not only for small watersheds but also for larger drainage basins, by dividing the basin into smaller watersheds. The DSS was validated for a watershed on the Caribbean island of St Lucia and used to suggest measures for a 10° slope under specific soil type, sediment loss and LCC conditions. The measures proposed included bench terraces, graded contour bunds, conservation ditches, concrete chute spillways, diversion dams and conservation cropping systems. The measures actually adopted on‐site were conservation ditches, graded contour bunds and conservation cropping systems, a close parallel to the DSS's proposed measures. On slopes ranging from 5–55°, implementation of the suggested control measures resulted in a 34–37 per cent reduction in soil loss on the watershed. Copyright © 2004 John Wiley & Sons, Ltd.
Accurate measurement, using natural sunlight, of silicon solar cells
Authors: Keogh William M. , Blakers Andrew W. 
Published: January 2004

AbstractThe light source is very important when measuring solar cells. Commonly used light sources—good‐quality solar simulators—are expensive and have far from ideal characteristics. Computer modelling described in this work strongly suggests that testing of silicon solar cells under natural sunlight is simpler, cheaper, and more accurate than all but the most careful simulator measurements. Direct‐beam solar spectra were generated with the model SMARTS2 for a range of atmospheric conditions, and a broad range of silicon cells (efficiencies 6–25%) were then simulated under these spectra. These simulations showed that measurement uncertainty of less than 5% should be achievable. Climate data for locations within 45° of the equator show that the required atmospheric conditions should occur commonly in summer. Finally, it is shown that the important atmospheric conditions can be measured without expensive equipment. Copyright © 2004 John Wiley & Sons, Ltd.
Low‐temperature formation of local Al contacts to a‐Si:H‐passivated Si wafers
Authors: Plagwitz H. , Nerding M. , Ott N. , Strunk H. P. , Brendel R. 
Published: January 2004

AbstractWe have passivated boron‐doped, low‐resistivity crystalline silicon wafers on both sides by a layer of intrinsic, amorphous silicon (a‐Si:H). Local aluminum contacts were subsequently evaporated through a shadow mask. Annealing at 210°C in air dissolved the a‐Si:H underneath the Al layer and reduces the contact resistivity from above 1 Ω cm2to 14·9 m Ω cm2. The average surface recombination velocity is 124 cm/s for the annealed samples with 6% metallization fraction. In contrast to the metallized regions, no structural change is observed in the non‐metallized regions of the annealed a‐Si:H film, which has a recombination velocity of 48 cm/s before and after annealing. Copyright © 2004 John Wiley & Sons, Ltd.
Solar cell efficiency tables (version 23)
Authors: Green Martin A. , Emery Keith , King David L. , Igari Sanekazu , Warta Wilhelm 
Published: January 2004

AbstractConsolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined and new entries since July 2003 are reviewed. Copyright © 2004 John Wiley & Sons, Ltd.
Properties of ZnO/CdS/CuInSe2solar cells with improved performance
Authors: AbuShama Jehad A. M. , Johnston S. , Moriarty T. , Teeter G. , Ramanathan K. , Noufi R. 
Published: January 2004

AbstractWe report the growth and characterization of low‐bandgap record‐efficiency ZnO/CdS/CuInSe2thin‐film solar cells. The total area conversion efficiency for this cell is 14·5%. This result has been measured and confirmed at the National Renewable Energy Laboratory under standard reporting conditions (1000 W/m2, 25°C, AM1·5 Global). The improved performance of the CuInSe2solar cell is primarily due to a high current density. Material and device characterization data are presented.. Published in 2004 by John Wiley & Sons, Ltd.
A proteomic approach to study Salmonella typhi periplasmic proteins altered by a lack of the DsbA thiol: Disulfide isomerase
Authors: Agudo David , Mendoza María Teresa , Castañares Cristina , Nombela César , Rotger Rafael 
Published: January 2004

AbstractTwo‐dimensional electrophoresis (2‐DE) was used to analyze the pleiotropic effects of a deficiency in DsbA, a periplasmic disulfide‐bond oxidoreductase, in Salmonella typhi. With this aim, the dsbA gene was cloned and assayed for activity in a dsbA‐null mutant of Escherichia coli. A dsbA/chloramphenicol acetylase construct was then used to disrupt the wild‐type gene of S. typhi. The resultant dsbA‐null mutant of S. typhi, like the E. coli mutant, exhibited a lack of flagellation and of glucose‐1‐phosphatase activity. Periplasmic extracts from the parental and mutant strains were analyzed by 2‐DE using standard denaturing and nondenaturing conditions. Differences in protein expression were more marked in nondenaturing conditions. Ninety‐nine protein spots were analyzed by peptide mass fingerprinting, and 65 spots were identified by searching a S. typhi database. Twenty‐five spots were exclusively detected in the wild‐type strain, 10 were found only in the mutant strain, and 21 were common to both strains. We observed a lack of DsbA, glucose‐1‐phosphatase and flagellin in the dsbA‐null mutant, which explains two of the observed phenotypes. The AI‐2 autoinducer‐producing protein LuxS, which is involved in quorum‐sensing signalling was also absent.
Copper‐associated liver disease: A proteomics study of copper challenge in a sheep model
Authors: Simpson Deborah M. , Beynon Robert J. , Robertson Duncan H. L. , Loughran Michael J. , Haywood Susan 
Published: January 2004

AbstractSheep display a variant phenotype with respect to their susceptibility to copper and derivative pathology. The North Ronaldsay sheep are acutely sensitive to environmental copper while the Cambridge breed is much more copper‐tolerant. A study of protein expression in the liver of the two different breeds of sheep as a result of copper challenge would aid in the understanding of their differing pathophysiologies and contribute to knowledge of copper toxicosis in man. In this initial study, Cambridge breed sheep were challenged with oral copper and liver proteins were analyzed by two‐dimensional (2‐D) gel electrophoresis. Proteins whose expression pattern was modified by copper exposure were then identified by peptide mass fingerprinting using matrix assisted laser desorption/ionization‐time of flight (MALDI‐TOF) mass spectrometry. In conclusion, the pattern of changes in protein expression were consistent with an early adaptive response to oxidative challenge. This was followed by evidence of an impaired ability of the liver to compensate as copper loading increased, accompanied by oxidative stress‐induced injury.
Dissecting regulatory networks by means of two‐dimensional gel electrophoresis: Application to the study of the diauxic shift in the yeast Saccharomyces cerevisiae
Authors: Haurie Valérie , Sagliocco Francis , Boucherie Hélian 
Published: January 2004

AbstractUsing a proteomic approach based on the two‐dimensional (2‐D) gel analysis of synthesized proteins, we investigated the involvement of the Snf1 kinase pathway in the regulation of gene expression during the diauxic shift in Saccharomyces cerevisiae. For this purpose, we used a mutant strain deleted for SNF4, the gene coding for the activator subunit of Snf1p. The levels of synthesis of 82 spots were found to be affected by the absence of Snf4p at the diauxic shift. Half of the proteins which exhibit a reduced synthesis in the mutant strain are proteins whose genes are controlled by the transcriptional activator Cat8p, a target of Snf1p. Proteins with an increased level of synthesis in the mutant strain were also observed. Among them are glycolytic enzymes whose synthesis is strongly reduced when wild‐type cells enter the diauxic shift. This observation suggests that Snf1p exerts a negative control on the expression of glycolytic genes during the diauxic transition. The results obtained in this study were compiled with those previously obtained by similar proteomic approach with other regulatory factors involved in the diauxic shift. This compilation illustrates how 2‐D gel electrophoresis can be used to elucidate the network of regulators participating to complex biological process.
Proteomic analysis of the effect of heat stress on hexaploid wheat grain: Characterization of heat‐responsive proteins from non‐prolamins fraction
Authors: Majoul Thouraya , Bancel Emmanuelle , Triboï Eugène , Ben Hamida Jeannette , Branlard Gérard 
Published: January 2004

AbstractThe effect of heat stress on hexaploid wheat grain proteome was recently analyzed in our previous works. Proteomic tools allowed the characterization of heat‐responsive proteins of total endosperm, composed mainly of prolamins. The present work completes this study; our aim was to analyze the effect of heat stress on the water‐soluble fraction, composed essentially of albumins and globulins. These proteins were separated by two‐dimensional electrophoresis (2‐DE), visualized by Coomassie Brilliant Blue (CBB) staining and analyzed by Melanie‐3 software. Of the 43 heat‐changed proteins, 24 were found to be up‐regulated whereas 19 spot proteins were down‐regulated. All of these proteins were subjected to matrix‐assisted laser desorption/ionization‐time of flight‐mass spectrometry (MALDI‐TOF‐MS) followed by database searching which allowed the identification of 42 spots. Of these, some were enzymes involved in different metabolic pathways of plants, such as granule‐bound starch synthase and glucose‐1‐phosphate adenyltransferase, involved in the starch synthesis pathway; β‐amylase, involved in carbohydrate metabolism, and the ATP synthase β‐chain that was related to four heat‐decreased proteins. Moreover, five heat up‐regulated proteins showed similarities with small heat shock proteins while three other spots were related to elongation factors or eucaryotic translation initiation factors. Proteins involved in abiotic stresses or in plant defense mechanism were also identified and are discussed.
Application of proteomics in phylogenetic and evolutionary studies
Authors: Navas Alfonso , Albar Juan Pablo 
Published: January 2004

AbstractThere are few papers that deal specifically with evolutionary studies and proteomics. However, applying proteomics to these studies promises to open new perspectives apropos the construction of phylogenetic trees and the detection of evolutionary changes. Principles and methods of phylogenetic systematics could be used to compare and evaluate proteomes. This would permit the detection and characterization of specific proteins that have evolutionary value in defining monophyly, paraphyly, and polyphyly.
Systematic screening of reactive cysteine proteomes
Authors: Lindahl Marika , Florencio Francisco J. 
Published: January 2004

AbstractRedox signalling constitutes a topic within the field of cellular signal transduction which is attracting increasing interest. A major challenge is to identify the components of redox signalling pathways. Proteins containing cysteines that may reversibly form disulphides are principal candidates as transmitters of redox signals. Thioredoxins are small proteins containing a highly reactive dithiol. Here we present a simple procedure to isolate and separate proteins that contain redox active cysteines using a site‐directed, histidine‐tagged mutant of thioredoxin, which forms stable mixed disulphides with its targets.