bluuebunny/crossref_metadata_2025_split huggingface dataset:
Estimating phosphorus delivery with its mitigation measures from soil to stream using fuzzy rules
Authors: Zhang T. , Page T. , Heathwaite L. , Beven K. , Oliver D. M. , Haygarth P. M. 
Published: March 2013

AbstractTo meet our environmental management responsibilities, there is a need to estimate the likely effect of current and future soil and land management policies on water quality and choose the most effective strategies given catchment characteristics, climate and economic drivers. Efficient management of diffuse phosphorus (P) delivery from agricultural soils to streams requires mitigation strategies to be modelled such that catchment mitigation strategies can be optimized. Owing to limited catchment‐scale experimental results upon which a mitigation measure rule‐base can be based, expert opinion was employed to make scale‐dependent extrapolations from the information available. Riparian buffer zone and wetlands are selected as two examples showing how the fuzzy rules are built. We discuss the challenges in the derivation and implementation of the fuzzy rules for the mitigation measures effectiveness such as, P trapping efficiency, up‐scaling process, catchment properties effect and the combination effect. The results demonstrated how effective each mitigation method could be for reducing the P delivery coefficient and that mitigation options should be selected according to catchment properties. This model can be applied for the evaluation of the effect of installed and to be installed mitigation measures on P delivery coefficient and give support for land management strategies.
Changes in plant‐available and easily soluble phosphorus within 1 year after P amendment
Authors: Djodjic F. , Mattsson L. 
Published: March 2013

AbstractDiffuse losses of phosphorus (P) from arable land are often related to soil P and P amendments. We follow the in situ dynamics of plant‐available [ammonium lactate/acetic acid (P‐AL)] and easily soluble (0.01 m CaCl2) P during 1 year after fertilizer application at five sites in long‐term fertility field experiments in Sweden with three different soil P levels and amendment rates and two different crop rotation systems. Clear differences between soils and P treatments were found. These can to a large extent be explained by the amount of applied of P and soil sorption capacity. The ‘bell curve’ indicating the development of plant‐available P can be described successfully using Gaussian modelling. Strong correlation between plant‐available and easily soluble P as determined by the above‐mentioned methods shows that the existing agronomic soil test P can be a good indicator even for easily soluble P, especially if other soil properties such as soil sorption capacity are taken into account. From the management standpoint, small increases in both plant‐available and easily soluble P as in the P replacement treatment indicate that such a management strategy may reduce environmental risks as a result of P amendments. Increases in P amendments above the agronomic optimum increased plant‐available P for a considerable time after P amendment (2–4 months) to indicate high environmental risk.
Assessment of phosphorus fertilizer practices in altered wetland soils using uncertainty analysis
Authors: Litaor M. I , Chashmonai I. , Barnea I. , Reichmann O. , Shenker M. 
Published: March 2013

AbstractIntensive P fertilizer application is widely practised in East Mediterranean altered wetland soils, even when results from the Olsen‐P extract indicate sufficiency (>10 mg P/kg). To reduce or even eliminate this practice we conducted a large field study to test the feasibility of a major reduction in the use of P fertilizers. A total of 90 sample sites were evenly spaced with respect to their parent material (deep peat, shallow peat, marl). Soils were analysed for Olsen‐P, bulk density, pH, electrical conductivity, and nitrate, chloride and sulphate in saturated paste extracts. We determined variograms and estimated the spatial structure of Olsen‐P data by ordinary kriging. We then used a sequential Gaussian model to produce 100 alternative simulations to measure the joint spatial uncertainty of P concentrations in the study area (ca. 1500 ha). Finally, we post‐processed the simulation results to compute the probability of exceeding the threshold Olsen‐P value of 10 mg/kg. The simulation results indicate a high probability of exceeding the 10 mg/kg threshold in most peat soils supporting an earlier recommendation to reduce or even eliminate P fertilizer application in these fields. On the other hand, a very low probability of exceeding this threshold was observed in most marl soils justifying continued fertilizer application. However, the added P is likely to affect adjacent waterways and increase potential downstream eutrophication due to high conductance and flow continuity between the marl soils and adjacent waterways.
Managing farmed closed depressional areas using blind inlets to minimize phosphorus and nitrogen losses
Authors: Smith D. R. , Livingston S. J. 
Published: March 2013

AbstractClosed depressions are sites within a landscape from glacial origin in which runoff water tends to collect because there is no natural outlet. When farmed, this water is often drained via a tile riser, a vertical tube that connects the bottom of the low point of a closed depression with the subsurface tile drainage network. Two field‐sized closed depressions (ca. 4 ha) and two small catchments (ca. 300 ha) were used to test the hypothesis that water quality could be improved by replacing tile risers with blind inlets, ca. 18 m2 holes filled to 1 m depth so that a high infiltration capacity was attained. At the field scale discharge, sediment and nutrient loads were lower when drained with the blind inlet compared to the tile riser. Late Spring 2010 was much wetter than normal, and increased nutrient loading was observed in both small catchments compared with previous years. In 2010, discharge and total P loading from Catchment AME (control catchment drained with tile risers) increased 417% and 737%, respectively, compared to the mean for the six previous years, whereas in Catchment BME (treatment catchment drained with blind inlets), there was only a 64% and 92% increase, respectively. Results from this study indicate that replacing tile risers with blind inlets to drain closed depressions may be one method to effectively reduce nutrient and sediment loading to Lake Erie and other sensitive water bodies that lie in landscapes formed by Wisconsin, Weichselian or Devensian glaciation.
Effectiveness of buffer strips without added fertilizer to reduce phosphorus loads from flat fields to surface waters
Authors: Noij I. G. A. M. , Heinen M. , Heesmans H. I. M. , Thissen J. T. N. M. , Groenendijk P. 
Published: March 2013

AbstractBuffer strips with no added fertilizers are a mitigation measure to reduce P loads from agricultural land to surface water. However, the experimental evidence on their effectiveness (BSE) has been from sloping locations with shallow flow and surface runoff. The aim of this experimental study was to quantify BSE for P on flat agricultural lowland, predominantly with deep flow. We selected sites characteristic of five major hydrogeological classes in the Netherlands and in each experimental field installed paired 5‐m‐wide unfertilized grass (BS) and reference treatments (REF) that abutted the ditch. The REF treatments were managed similar to the adjacent grass or maize field, but BS treatments were only harvested. Each treatment had a reservoir in the ditch to collect and measure discharge and flow‐proportional P concentration for 3 or 4 yr. We also measured net P withdrawal, the P status of the soil and P concentration in upper groundwater. We found a significant BSE for P of 61% on the site with the shallowest flow and steepest slope (2%). At the other sites, BSE was low and statistically insignificant. We conclude that harvested unfertilized buffer strips reduce P loads from flat fields only in specific areas with high surface runoff and/or shallow flow, especially in combination with a high original soil P status.
Continental estimates of forest cover and forest cover changes in the dry ecosystems of Africa between 1990 and 2000
Authors: Bodart Catherine , Brink Andreas B. , Donnay François , Lupi Andrea , Mayaux Philippe , Achard Frédéric 
Published: March 2013

AbstractAimThis study provides regional estimates of forest cover in dry African ecoregions and the changes in forest cover that occurred there between 1990 and 2000, using a systematic sample of medium‐resolution satellite imagery which was processed consistently across the continent.LocationThe study area corresponds to the dry forests and woodlands of Africa between the humid forests and the semi‐arid regions. This area covers the Sudanian and Zambezian ecoregions.MethodsA systematic sample of 1600 Landsat satellite imagery subsets, each 20 km × 20 km in size, were analysed for two reference years: 1990 and 2000. At each sample site and for both years, dense tree cover, open tree cover, other wooded land and other vegetation cover were identified from the analysis of satellite imagery, which comprised multidate segmentation and automatic classification steps followed by visual control by national forestry experts.ResultsLand cover and land‐cover changes were estimated at continental and ecoregion scales and compared with existing pan‐continental, regional and local studies. The overall accuracy of our land‐cover maps was estimated at 87%. Between 1990 and 2000, 3.3 million hectares (Mha) of dense tree cover, 5.8 Mha of open tree cover and 8.9 Mha of other wooded land were lost, with a further 3.9 Mha degraded from dense to open tree cover. These results are substantially lower than the 34 Mha of forest loss reported in the FAO's 2010 Global Forest Resources Assessment for the same period and area.Main conclusionsOur method generates the first consistent and robust estimates of forest cover and change in dry Africa with known statistical precision at continental and ecoregion scales. These results reduce the uncertainty regarding vegetation cover and its dynamics in these previously poorly studied ecosystems and provide crucial information for both science and environmental policies.
Genetic, phenotypic and ecological divergence with gene flow at the Isthmus of Tehuantepec: the case of the azure‐crowned hummingbird (Amazilia cyanocephala)
Authors: Rodríguez‐Gómez Flor , Gutiérrez‐Rodríguez Carla , Ornelas Juan Francisco 
Published: March 2013

AbstractAimWe test whether populations of the Mesoamerican azure‐crowned hummingbird, Amazilia cyanocephala (Trochilidae), located east and west of the Isthmus of Tehuantepec are genetically, morphologically and environmentally differentiated and examine the relative role of drift and selection in driving diversification.LocationMexico.MethodsWe sequenced the mitochondrial ATPase‐6 and ATPase‐8 genes and the control region of 130 individuals collected throughout the range of the species in Mexico. Population genetic methods and coalescent tests were used to reconstruct the phylogeography of the species. Morphological and niche variation between genetic groups of A. cyanocephala were assessed.ResultsThe data revealed two genetic groups separated by the Isthmus of Tehuantepec in the late Pleistocene (49,300–75,800 years ago), with the split occurring in the presence of gene flow. Deviations from demographic equilibrium were detected for the two genetic groups, indicating more recent population expansions. Amazilia cyanocephala individuals from populations on either side of the Isthmus of Tehuantepec differed in morphology and were distributed in unique environmental space. A coalescent‐based test indicated that selection is driving the observed morphological differentiation.Main conclusionsOur findings implicate the Isthmus of Tehuantepec as a permeable barrier driving recent diversification of A. cyanocephala in the presence of gene flow. The two A. cyanocephala mitochondrial DNA (mtDNA) groups corresponding with morphological and environmental niche differences, in concert with the results of a coalescent‐based test, suggest that selection has been strong enough to counteract the effects of gene flow.
Factors of learner–instructor interaction which predict perceived learning outcomes in online learning environment
Authors: Kang M. , Im T. 
Published: March 2013

AbstractInteraction in the online learning environment has been regarded as one of the most critical elements that affect learning outcomes. This study examined what factors in learner–instructor interaction can predict the learner's outcomes in the online learning environment. Learners in K Online University participated by answering the survey, and data from 654 respondents were analysed for this study. Results showed that factors related to instructional interaction predicted perceived learning achievement and satisfaction better than factors related to social interaction. However, it was revealed that social interaction such as social intimacy could negatively affect perceived learning achievement and satisfaction. This study has value because it found factors under learner–instructor interaction which predict perceived learning achievement and satisfaction with empirical evidence.
Anal intraepithelial neoplasia in a sexually transmitted diseases outpatient clinic: correlation with cytological screening
Authors: Repiso Jiménez J.B. , Frieyro‐Elicegui M. , Padilla‐España L. , Palma‐Carazo F. , de la Torre Lima J. , Rivas‐Ruiz F. 
Published: March 2013

AbstractBackgroundHigh‐grade anal intraepithelial neoplasia (AIN) is currently considered a precursor of anal cancer. The population most susceptible to AIN is men who have sex with men (MSM), especially if they are infected by HIV.ObjectivesWe analysed the population diagnosed with AIN and evaluated anal cytology as a method of screening the at‐risk population.MethodsWe undertook a retrospective review of patients diagnosed with AIN by means of a surgical biopsy between 2008 and 2010. We analysed the risk factors of the population affected and the degree of agreement with the cytology performed previously.ResultsDuring the study period 41 patients were diagnosed with AIN and seven with anal canal carcinoma in situ; 77% were men, most MSM. A history of receptive anal intercourse was found in 81% of the patients and in 71% there was an association with anogenital warts; 32 patients were HIV‐positive, most of them men. Of the patients with anal dysplasia of any type in the cytology, 90% had some grade of AIN or carcinoma in situ in the later biopsy. The degree of agreement between the cytology and the biopsy was 94% in the high‐grade dysplasias and 50% in the low‐grade dysplasias.ConclusionsAnal cytology in at‐risk populations has a high degree of agreement with the biopsy when performed surgically, though less in low‐grade dysplasias, which must always be studied. More studies evaluating the degree of progression of AIN to anal cancer are necessary.
Effects of ornamentation and phylogeny on the evolution of wing shape in stalk‐eyed flies (Diopsidae)
Authors: Husak J. F. , Ribak G. , Baker R. H. , Rivera G. , Wilkinson G. S. , Swallow J. G. 
Published: March 2013

AbstractExaggerated male ornaments are predicted to be costly to their bearers, but these negative effects may be offset by the correlated evolution of compensatory traits. However, when locomotor systems, such as wings in flying species, evolve to decrease such costs, it remains unclear whether functional changes across related species are achieved via the same morphological route or via alternate changes that have similar function. We conducted a comparative analysis of wing shape in relation to eye‐stalk elongation across 24 species of stalk‐eyed flies, using geometric morphometrics to determine how species with increased eye span, a sexually selected trait, have modified wing morphology as a compensatory mechanism. Using traditional and phylogenetically informed multivariate analyses of shape in combination with phenotypic trajectory analysis, we found a strong phylogenetic signal in wing shape. However, dimorphic species possessed shifted wing veins with the result of lengthening and narrowing wings compared to monomorphic species. Dimorphic species also had changes that seem unrelated to wing size, but instead may govern wing flexion. Nevertheless, the lack of a uniform, compensatory pattern suggests that stalk‐eyed flies used alternative modifications in wing structure to increase wing area and aspect ratio, thus taking divergent morphological routes to compensate for exaggerated eye stalks.
Morphology and Phylogeny of Three New Loxophyllum Species (Ciliophora, Pleurostomatida) from Mangrove Wetlands of Southern China
Authors: Wu Lei , Chen Ruimin , Yi Zhenzhen , Li Jiqiu , Warren Alan , Lin Xiaofeng 
Published: March 2013

AbstractThree new pleurostomatid ciliates, Loxophyllum meridionale sp. n., L. salinum sp. n., and L. planum sp. n., isolated from brackish waters of mangrove wetlands in southern China, were investigated using live observation and protargol impregnation. The main characteristic feature of L. meridionale sp. n. is the presence of three contractile vacuoles (CVs) along its dorsal margin. Loxophyllum salinum sp. n. can be identified by the presence of three closely spaced CVs along the ventral margin and 12–15 right and four to six left kineties. Loxophyllum planum sp. n. is characterized by the combination of two macronuclei, a single, subterminal CV, and the absence of cortical granules. Phylogenetic trees based on the small subunit rDNA sequence data recovered Loxophyllum as a monophyletic group within the pleurostomatids. Loxophyllum meridionale sp. n., L. salinum sp. n., and L. planum sp. n. were all nested within the Loxophyllum clade. Based on its ciliary pattern and general morphological features, Loxophyllum asetosum is transferred to the genus Amphileptus and a new combination is suggested: Amphileptus asetosus (Burkovsky 1970) comb. n. [basionym L. asetosum Burkovsky 1970].
Retracted: Localizing and extracting filament distributions from microscopy images
Authors: BASU S. , DAHL K.N. , ROHDE G.K. 
Published: March 2013

SummaryDetailed quantitative measurements of biological filament networks represent a crucial step in understanding architecture and structure of cells and tissues, which in turn explain important biological events such as wound healing and cancer metastases. Confocal microscope images of biological specimens marked for different structural proteins constitute an important source for observing and measuring meaningful parameters of biological networks. Unfortunately, current efforts at quantitative estimation of architecture and orientation of biological filament networks from microscopy images are predominantly limited to visual estimation and indirect experimental inference. Here we describe a new method for localizing and extracting filament distributions from 2D confocal microscopy images. The method combines a filter‐based detection of pixels likely to contain a filament with a constrained reverse diffusion‐based approach for localizing the filaments centrelines. We show with qualitative and quantitative experiments, using both simulated and real data, that the new method can provide more accurate centreline estimates of filament in comparison to other approaches currently available. In addition, we show the algorithm is more robust with respect to variations in the initial filter‐based filament detection step often used. We demonstrate the application of the method in extracting quantitative parameters from an experiment that seeks to quantify the effects of carbon nanotubes on actin cytoskeleton in live HeLa cells. We show that their presence can disrupt the overall actin cytoskeletal organization in such cells.
Emotional Work and Diversity in Clinical Placements of Nursing Students
Authors: Arieli Daniella 
Published: March 2013

AbstractPurposeTo learn how students experience clinical placements in a setting of diversity and how they cope with the emotional challenges involved.DesignThis study is based on inductive, qualitative research undertaken with Israeli nursing students.MethodIn‐depth interviews were conducted with 20 students: 10 Arabs (5 men and 5 women), 9 Jews (2 men and 7 women), and 1 Circassian. The interviews were analyzed through coding and categorization.FindingsThe students’ experiences are characterized by emotional strains of various sorts—stress, ambivalence, disgust, frustration, and conflict—that arise in three types of relationships: relationships with patients, with the clinical instructors, and with other students who are on their teams. The data show that diversity has an impact on all these relationships. The data further show that the students cope with the emotional strains by using several strategies of emotional work: distancing, self‐strengthening, self‐motivation work, and minimizing significance.Conclusions and Implications(a) Nursing students’ experiences during their clinical placements should be understood in terms of emotional challenges, and their emotional work and coping strategies call for appropriate forms of support. (b) The diversity of the clinical placement environment should be considered as an important factor, both in understanding students’ experiences and learning processes and in designing the support that they need.Clinical RelevanceCulturally diverse settings entail distinct challenges that impact students’ emotional reaction to clinical work. Understanding the types of emotional work students do in the process of their clinical experience is critical for educators seeking to promote genuinely caring and effective nursing in culturally diverse settings.
The role of muscle‐specific tyrosine kinase (MuSK) and mystery of MuSK myasthenia gravis
Authors: Koneczny Inga , Cossins Judith , Vincent Angela 
Published: March 2013

AbstractMuSK myasthenia gravis is a rare, severe autoimmune disease of the neuromuscular junction, only identified in 2001, with unclear pathogenic mechanisms. In this review we describe the clinical aspects that distinguish MuSK MG from AChR MG, review what is known about the role of MuSK in the development and function of the neuromuscular junction, and discuss the data that address how the antibodies to MuSK lead to neuromuscular transmission failure.
Managing Partners and Management Professionals: Institutional Work Dyads in Professional Partnerships
Authors: Empson Laura , Cleaver Imogen , Allen Jeremy 
Published: March 2013

AbstractThis study presents an empirical analysis of the micro‐dynamics of institutional work. Examining the ‘corporatization’ of large international law firm partnerships, the study identifies the dyadic relationship that develops between two different types of professionals, the managing partner and management professional, and demonstrates how their relationship becomes a key mechanism for institutional work. The study shows how, by working together, these individuals take advantage of differences in their relative social positions: specifically their formal authority, specialist expertise, and social capital. The study identifies seven forms of institutional work in which they engage and demonstrates how these multiple forms simultaneously encompass the creation, maintenance,anddisruption of the institution of partnership. The study argues that this simultaneous occurrence helps to account for the phenomenon of sedimentation, whereby the gradually emerging institutional logic of the corporatized partnership is being integrated into the traditional partnership form.