Recharge and flow processes in a till aquitard

DEFF Research Database (Denmark)

Schrøder, Thomas Morville; Høgh Jensen, Karsten; Dahl, Mette

1999-01-01

Eastern Denmark is primarily covered by clay till. The transformation of the excess rainfall into laterally diverted groundwater flow, drain flow, stream flow, and recharge to the underlying aquifer is governed by complicatedinterrelated processes. Distributed hydrological models provide a framew......Eastern Denmark is primarily covered by clay till. The transformation of the excess rainfall into laterally diverted groundwater flow, drain flow, stream flow, and recharge to the underlying aquifer is governed by complicatedinterrelated processes. Distributed hydrological models provide...... a framework for assessing the individual flow components and forestablishing the overall water balance. Traditionally such models are calibrated against measurements of stream flow, head in the aquiferand perhaps drainage flow. The head in the near surface clay till deposits have generally not been measured...... the shallow wells and one in the valley adjacent to the stream. Precipitation and stream flow gauging along with potential evaporation estimates from a nearby weather station provide the basic data for the overall water balance assessment. The geological composition was determined from geoelectrical surveys...

Tillämpning av IAS 40 i onoterade fastighetsbolag

OpenAIRE

Wallin, Fredrik; Nilsson, Karolina; Ericsson, Marina

2006-01-01

Enligt IAS 40 – Förvaltningsfastigheter, definieras förvaltningsfastigheter som ”mark eller byggnader eller del av byggnad som innehas i syfte att generera hyresinkomster eller värdestegring”. Onoterade fastighetsbolag i Sverige har idag möjlighet att välja mellan att värdera sina fastigheter till anskaffningsvärde eller verkligt värde. IAS – International Accounting Standards är en internationell redovisningsstandard inom EU som började tillämpas i januari 2001, men blev obligatorisk för bör...

Racial Coverage of the 1950s Print Media and the Case of Emmett Till.

Science.gov (United States)

Rhodes, Jane

The Emmett Till murder case in 1955 marked the turning point in the coverage of blacks by the white American press. Till, a black teenager from Chicago, was murdered in 1955 while visiting relatives in Mississippi. The Till murder was covered extensively in the press, since the two white men charged with killing him were acquitted by an all-white,…

Impact of no-till and conventional tillage practices on soil chemical properties

International Nuclear Information System (INIS)

Aziz, A.; Bangash, N.

2015-01-01

There is a global concern about progressive increase in the emission of greenhouse gases especially atmosphere CO/sub 2/. An increasing awareness about environmental pollution by CO/sub 2/ emission has led to recognition of the need to enhance soil C sequestration through sustainable agricultural management practices. Conservation management systems such as no-till (NT) with appropriate crop rotation have been reported to increase soil organic C content by creating less disturbed environment. The present study was conducted on Vanmeter farm of The Ohio State University South Centers at Piketon Ohio, USA to estimate the effect of different tillage practices with different cropping system on soil chemical properties. Tillage treatments were comprised of conventional tillage (CT) and No-till (NT).These treatments were applied under continuous corn (CC), corn-soybean (CS) and corn soybean-wheat-cowpea (CSW) cropping system following randomized complete block design. No-till treatment showed significant increase in total C (30%), active C (10%), and passive salt extractable (18%) and microwave extractable C (8%) and total nitrogen (15%) compared to conventional tillage practices. Total nitrogen increased significantly 23 % in NT over time. Maximum effect of no-till was observed under corn-soybean-wheat-cowpea crop rotation. These findings illustrated that no-till practice could be useful for improving soil chemical properties. (author)

EcoTILLING in Capsicum species: searching for new virus resistances

Directory of Open Access Journals (Sweden)

Nuez Fernando

2010-11-01

Full Text Available Abstract Background The EcoTILLING technique allows polymorphisms in target genes of natural populations to be quickly analysed or identified and facilitates the screening of genebank collections for desired traits. We have developed an EcoTILLING platform to exploit Capsicum genetic resources. A perfect example of the utility of this EcoTILLING platform is its application in searching for new virus-resistant alleles in Capsicum genus. Mutations in translation initiation factors (eIF4E, eIF(iso4E, eIF4G and eIF(iso4G break the cycle of several RNA viruses without affecting the plant life cycle, which makes these genes potential targets to screen for resistant germplasm. Results We developed and assayed a cDNA-based EcoTILLING platform with 233 cultivated accessions of the genus Capsicum. High variability in the coding sequences of the eIF4E and eIF(iso4E genes was detected using the cDNA platform. After sequencing, 36 nucleotide changes were detected in the CDS of eIF4E and 26 in eIF(iso4E. A total of 21 eIF4E haplotypes and 15 eIF(iso4E haplotypes were identified. To evaluate the functional relevance of this variability, 31 possible eIF4E/eIF(iso4E combinations were tested against Potato virus Y. The results showed that five new eIF4E variants (pvr210, pvr211, pvr212, pvr213 and pvr214 were related to PVY-resistance responses. Conclusions EcoTILLING was optimised in different Capsicum species to detect allelic variants of target genes. This work is the first to use cDNA instead of genomic DNA in EcoTILLING. This approach avoids intronic sequence problems and reduces the number of reactions. A high level of polymorphism has been identified for initiation factors, showing the high genetic variability present in our collection and its potential use for other traits, such as genes related to biotic or abiotic stresses, quality or production. Moreover, the new eIF4E and eIF(iso4E alleles are an excellent collection for searching for new resistance

Multivariate analysis and visualization of soil quality data for no-till systems.

Science.gov (United States)

Villamil, M B; Miguez, F E; Bollero, G A

2008-01-01

To evidence the multidimensionality of the soil quality concept, we propose the use of data visualization as a tool for exploratory data analyses, model building, and diagnostics. Our objective was to establish the best edaphic indicators for assessing soil quality in four no-till systems with regard to functioning as a medium for crop production and nutrient cycling across two Illinois locations. The compared situations were no-till corn-soybean rotations including either winter fallowing (C/S) or cover crops of rye (Secale cereale; C-R/S-R), hairy vetch (Vicia villosa; C-R/S-V), or their mixture (C-R/S-VR). The dataset included the variables bulk density (BD), penetration resistance (PR), water aggregate stability (WAS), soil reaction (pH), and the contents of soil organic matter (SOM), total nitrogen (TN), soil nitrates (NO(3)-N), and available phosphorus (P). Interactive data visualization along with canonical discriminant analysis (CDA) allowed us to show that WAS, BD, and the contents of P, TN, and SOM have the greatest potential as soil quality indicators in no-till systems in Illinois. It was more difficult to discriminate among WCC rotations than to separate these from C/S, considerably inflating the error rate associated with CDA. We predict that observations of no-till C/S will be classified correctly 51% of the time, while observations of no-till WCC rotations will be classified correctly 74% of the time. High error rates in CDA underscore the complexity of no-till systems and the need in this area for more long-term studies with larger datasets to increase accuracy to acceptable levels.

Integrity of clay till aquitards to DNAPL migration: Assessment using current and emerging characterization tools

DEFF Research Database (Denmark)

Fjordbøge, Annika Sidelmann; Janniche, Gry Sander; Jørgensen, Torben H.

2017-01-01

Field investigations were carried out to determine the occurrence of tetrachloroethene (PCE) dense non-aqueous phase liquid (DNAPL), the source zone architecture and the aquitard integrity at a 30-50 year old DNAPL release site. The DNAPL source zone is located in the clay till unit overlying......% of the total PCE mass. The data set, and associated data analysis, supported vertical migration of DNAPL through fractures in the upper part of the clay till, horizontal migration along high permeability features around the redox boundary in the clay till, and to some extent vertical migration through...... the fractures in the reduced part of the clay till aquitard to the underlying limestone aquifer. The aquitard integrity to DNAPL migration was found to be compromised at a thickness of reduced clay till of less than 2 m....

Modeling fine-scale geological heterogeneity-examples of sand lenses in tills

DEFF Research Database (Denmark)

Kessler, Timo Christian; Comunian, Alessandro; Oriani, Fabio

2013-01-01

that hamper subsequent simulation. Transition probability (TP) and multiple-point statistics (MPS) were employed to simulate sand lens heterogeneity. We used one cross-section to parameterize the spatial correlation and a second, parallel section as a reference: it allowed testing the quality......Sand lenses at various spatial scales are recognized to add heterogeneity to glacial sediments. They have high hydraulic conductivities relative to the surrounding till matrix and may affect the advective transport of water and contaminants in clayey till settings. Sand lenses were investigated...... on till outcrops producing binary images of geological cross-sections capturing the size, shape and distribution of individual features. Sand lenses occur as elongated, anisotropic geobodies that vary in size and extent. Besides, sand lenses show strong non-stationary patterns on section images...

Fluctuations of the Vestfonna ice margin at Brageneset, Nordaustlandet, Svalbard, after the last glacial maximum

Directory of Open Access Journals (Sweden)

Donner, J.J.

1995-06-01

Full Text Available Four radiocarbon datings of shells of Mya truncata and Saxicava arctica from the till of the end-moraine of the advance of Vestfonna against Brageneset, Nordaustlandet, between AD 1861 and 1899, gave ages between 8300 BP and 8700 BP. These are from the time when the ice margin had retreated from Brageneset after the last glaciation. An additional age of 7900 BP obtained for Astarteelliptica, also from the end-moraine, shows that the shells in the till represent a mixed death assemblage, as also shown by the composition of the molluscan fauna in general. By comparing the altitudes of the two pumice levels with their altitudes in other areas of Svalbard a curve for the relative uplift of Brageneset could be constructed. According to this curve the highest point of Brageneset at 46.5 m emerged at about 9200 BP, which gives a minimum age for the general deglaciation, an age in agreement with dates obtained from other parts of Nordaustlandet.

Modelling the Baltic power system till 2050

International Nuclear Information System (INIS)

Blumberga, Andra; Lauka, Dace; Barisa, Aiga; Blumberga, Dagnija

2016-01-01

Highlights: • A dynamic model was developed to evaluate changes in the energy system till 2050. • Wind energy has the potential to become dominant in the Baltic region. • Solar energy has the potential to become popular from 2025 till 2050. - Abstract: The European Union has given a long-term commitment towards a low-carbon society. Power sector is to play an important role in achieving ambitious emission reduction goals. This article presents results of a research aimed at evaluating development of the Baltic power system under current framework conditions. Special focus is put on renewable energy analysis to estimate the potential of power sector decarbonization. A dynamic energy-economy model was developed by applying system dynamics modelling approach in order to evaluate changes in the energy system till 2050. Underlying structure of the model is based on energy resource flows according to the national electricity mix of each Baltic State. The model calculates energy generation costs of each technology taking into account national support schemes. Based on cost estimation, the installed capacity of each energy resource is determined. Modelling results suggest that wind energy has the potential to become dominant in the Baltic region. This is explained by increasing competitiveness of wind-generated power price compared to fossil-fuel-based generation. Solar energy has the potential to become popular from 2025 onwards due to decreasing investment costs. The market share of other renewable electricity technologies, such as hydro and biomass, will continue to increase reaching maximum between 2020 and 2030. Biogas plants are still not expected to play considerable role in electricity generation.

Runoff losses of sediment and phosphorus from no-till and cultivated soils receiving dairy manure.

Science.gov (United States)

Verbree, David A; Duiker, Sjoerd W; Kleinman, Peter J A

2010-01-01

Managing manure in no-till systems is a water quality concern because surface application of manure can enrich runoff with dissolved phosphorus (P), and incorporation by tillage increases particulate P loss. This study compared runoff from well-drained and somewhat poorly drained soils under corn (Zea mays, L.) production that had been in no-till for more than 10 yr. Dairy cattle (Bos taurus L.) manure was broadcast into a fall planted cover crop before no-till corn planting or incorporated by chisel/disk tillage in the absence of a cover crop. Rainfall simulations (60 mm h(-1)) were performed after planting, mid-season, and post-harvest in 2007 and 2008. In both years and on both soils, no-till yielded significantly less sediment than did chisel/disking. Relative effects of tillage on runoff and P loss differed with soil. On the well-drained soil, runoff depths from no-till were much lower than with chisel/disking, producing significantly lower total P loads (22-50% less). On the somewhat poorly drained soil, there was little to no reduction in runoff depth with no-till, and total P loads were significantly greater than with chisel/disking (40-47% greater). Particulate P losses outweighed dissolved P losses as the major concern on the well-drained soil, whereas dissolved P from surface applied manure was more important on the somewhat poorly drained soil. This study confirms the benefit of no-till to erosion and total P runoff control on well-drained soils but highlights trade-offs in no-till management on somewhat poorly drained soils where the absence of manure incorporation can exacerbate total P losses.

ESR Dating Research of Glacial Tills in Tibetan Plateau

Science.gov (United States)

Bi, W.; Yi, C.

2016-12-01

In recent years, Quaternary Glacial-chronology has been made remarkable progress in the Tibetan Platean(TP) with the development of several numeric dating techniques, such as cosmogenic nuclides(NC), optically stimulated luminescence(OSL) and 14C. In constrast, the dating of Quaternary glacial tills in 100,000 years even more than million-year has been a challenge, just because the techniques has defects themselves and the sediments were stransformed during the geological and geomorphology progress later. Electron Spin Resonance(ESR) has been becoming one of the key methods of Quaternary Glacial-chronology with wide range of dating, expecially for the sample older than 100,000 years up to million-year scale. The accurate measurement of equivalent dose significantly impacts on accuracy and reliability of ESR dating method. Therefore, the study of the mechanisms of resetting processes is fundamental for accurate and reliable ESR dating. To understand the mechanism and characteristics of quartz ESR signal resetting of different samples, a series of laboratory simulation and field observation studies were carried out, which made lots of important breakthrough. But the research in quartz ESR signal of moraines is less and the test of ESR dating method is still in the qualitative investigation. Therefor, we use ESR dating and study on the mechanism and characteristics of quartz ESR signals in tills in the Tibetan Platean. In the adjust method of Modern, the quartz ESR signals in Modern glacial tills represent residual values which can be adjusted signals in the older glacial tills. As a consequence, ESR dating of the quartz in moraines needs to be explored in deep with building models to adjust ages which are measured by ESR dating. Therefore, ESR dating will become the trusted one of the cross dating methods in Quaternary Glacial-chronology with the adjust mothod improving the accuracy of ESR dating ages.

Soil physical and X-ray computed tomographic measurements to investigate small-scale structural differences under strip tillage compared to mulch till and no-till

Science.gov (United States)

Pöhlitz, Julia; Rücknagel, Jan; Schlüter, Steffen; Vogel, Hans-Jörg

2017-04-01

In recent years there has been an increasing application of conservation tillage techniques where the soil is no longer turned, but only loosened or left completely untilled. Dead plant material remains on the soil surface, which provides environmental and economic benefits such as the conservation of water, preventing soil erosion and saving time during seedbed preparation. There is a variety of conservation tillage systems, e.g. mulch till, no-till and strip tillage, which is a special feature. In strip tillage, the seed bed is divided into a seed zone (strip-till within the seed row: STWS) and a soil management zone (strip-till between the seed row: STBS). However, each tillage application affects physical soil properties and processes. Here, the combined application of classical soil mechanical and computed tomographic methods is used on a Chernozem (texture 0-30 cm: silt loam) to show small-scale structural differences under strip tillage (STWS, STBS) compared to no-till (NT) and mulch till (MT). In addition to the classical soil physical parameters dry bulk density and saturated conductivity (years: 2012, 2014, 2015) at soil depths 2-8 and 12-18 cm, stress-strain tests were carried out to map mechanical behavior. The stress-strain tests were performed for a load range from 5-550 kPa at 12-18 cm depth (year 2015). Mechanical precompression stress was determined on the stress-dry bulk density curves. Further, CT image cross sections and computed tomographic examinations (average pore size, porosity, connectivity, and anisotropy) were used from the same soil samples. For STBS and NT, a significant increase in dry bulk density was observed over the course of time compared to STWS and MT, which was more pronounced at 2-8 cm than at 12-18 cm depth. Despite higher dry bulk density, STBS displayed higher saturated conductivity in contrast to STWS, which can be attributed to higher earthworm abundance. In strip tillage, structural differences were identified

Cumulative impact of GM herbicide-tolerant cropping on arable plants assessed through species-based and functional taxonomies.

Science.gov (United States)

Squire, Geoffrey R; Hawes, Cathy; Begg, Graham S; Young, Mark W

2009-01-01

In a gradualist approach to the introduction of crop biotechnology, the findings of experimentation at one scale are used to predict the outcome of moving to a higher scale of deployment. Movement through scales had occurred for certain genetically modified herbicide-tolerant (GMHT) crops in the UK as far as large-scale field trials. However, the land area occupied by these trials was still field experiments. Data were used from experiments on the effect of (GMHT) crops and non-GM, or conventional, comparators in fields sown with four crop types (beet, maize, spring and winter oilseed rape) at a total of 250 sites in the UK between 2000 and 2003. Indices of biodiversity were measured in a split-field design comparing GMHT with the farmers' usual weed management. In the original analyses based on the means at site level, effects were detected on the mass of weeds in the three spring crops and the proportion of broadleaf and grass weeds in winter oilseed rape, but not on indices of plant species diversity. To explore the links between site means and total taxa, accumulation curves were constructed based on the number of plant species (a pool of around 250 species in total) and the number of plant functional types (24), inferred from the general life-history characteristics of a species. Species accumulation differed between GMHT and conventional treatments in direction and size, depending on the type of crop and its conventional management. Differences were mostly in the asymptote of the curve, indicative of the maximum number of species found in a treatment, rather than the steepness of the curve. In winter oilseed rape, 8% more species were accumulated in the GMHT treatment, mainly as a result of the encouragement of grass species by the herbicide when applied in the autumn. (Overall, GMHT winter oilseed rape had strong negative effects on both the food web and the potential weed burden by increasing the biomass of grasses and decreasing that of broadleaf weeds

Acidification of till in Northern Finland: experimental study

Directory of Open Access Journals (Sweden)

Aario, R.

1996-06-01

Full Text Available The acid neutralizing capacity of till and some effects promoted by increasing acidity, were studied in a number of tills in northern Finland. pH profiles were measured in the field and acid neutralizing capacity (ANC mmol/100 g sample in the laboratory as a function of the varying acidity in solution. The concentrations of Al, Ca, Mg, Fe, K, Mn, Zn, Cu and Sr in solutions were also analyzed. The results are presented in the form of graphs of ANC versus final pH of the solution and element concentration versus final pH. The total concentrations of the major elements were analyzed by XRF and those of trace elements by AAS. The pH measured in the test pits was lowest just below the ground surface, and rose rapidly to a value of 6 at a depth of about 1 m and then it remained more or less constant with depth. The laboratory analyses clearly suggest that the acid neutralizing capacity of till correlates well with sample depth. The ANC values, which represent the fast-working part of the capacity, are higher in the surficial parts owing to the easily soluble aluminium and iron hydroxides which have their origin in the weathering processes. The experiments resemble acid rain conditions, where the higher pH-level buffers are unable to neutralize the increase in acidity immediately, so that lower pH-level buffering processes such as Al and Fe hydroxide buffers come into play. The situation can be hazardous for both forests and surface water.

The spatial distribution of microfabric around gravel grains: indicator of till formation processes

Science.gov (United States)

KalväNs, Andis; Saks, Tomas

2010-05-01

Till micromorphology studies in thin sections is an established tool in the field of glacial geology. Often the thin sections are inspected only visually with help of mineralogical microscope. This can lead to subjective interpretation of observed structures. More objective method used in till micromorphology is measurement of apparent microfabric, usually seen as preferred orientation of elongated sand grains. In theses studies only small fraction of elongated sand grains often confined to small area of thin section usually are measured. We present a method for automated measurement of almost all elongated sand grains across the full area of the thin section. Apparently elongated sand grains are measured using simple image analysis tools, the data are processed in a way similar to regular till fabric data and visualised as a grid of rose diagrams. The method allows to draw statistical information about spatial variation of microfabric preferred orientation and fabric strength with resolution as fine as 1 mm. Late Weichselian tills from several sites in Western Latvia were studied and large variations in fabric strength and spatial distribution were observed in macroscopically similar till units. The observed types of microfabric spatial distributions include strong, monomodal and uniform distribution; weak and highly variable in small distances distribution; consistently bimodal distribution and domain-like pattern of preferred sand grain orientation. We suggest that the method can be readily used to identify the basic deformation and sedimentation processes active during the final stages of till formation. It is understood that the microfabric orientation will be significant affected by nearby large particles. The till is highly heterogonous sediment and the source of microfabric perturbations observed in thin section might lie outside the section plane. Therefore we suggest that microfabric distribution around visible sources of perturbation - gravel grains cut

Person till person kommunikation : Sociala mediers inverkan på det uppkopplade samhället

OpenAIRE

Kärrholm, Dan; Johansson, Henrik

2016-01-01

Denna kandidatuppsats undersöker eventuella risker för person till person kommunikation som kan härstammar i användning av moderna tekniken och de sociala medierna. Syftet är att ta reda på vilka konsekvenser som förekommer när man överkonsumerar modern teknik och diverse sociala medier (t.ex. Facebook, Twitter, instagram och Myspace). Undersökningen kommer sedan ligga till grund för ett gestaltningsarbete där fokusen ligger på att söka en teknik som kan förbättra kommunikationen person till ...

Towards a TILLING platform for functional genomics in Piel de Sapo melons

Directory of Open Access Journals (Sweden)

Pujol Marta

2011-08-01

Full Text Available Abstract Background The availability of genetic and genomic resources for melon has increased significantly, but functional genomics resources are still limited for this crop. TILLING is a powerful reverse genetics approach that can be utilized to generate novel mutations in candidate genes. A TILLING resource is available for cantalupensis melons, but not for inodorus melons, the other main commercial group. Results A new ethyl methanesulfonate-mutagenized (EMS melon population was generated for the first time in an andromonoecious non-climacteric inodorus Piel de Sapo genetic background. Diverse mutant phenotypes in seedlings, vines and fruits were observed, some of which were of possible commercial interest. The population was first screened for mutations in three target genes involved in disease resistance and fruit quality (Cm-PDS, Cm-eIF4E and Cm-eIFI(iso4E. The same genes were also tilled in the available monoecious and climacteric cantalupensis EMS melon population. The overall mutation density in this first Piel de Sapo TILLING platform was estimated to be 1 mutation/1.5 Mb by screening four additional genes (Cm-ACO1, Cm-NOR, Cm-DET1 and Cm-DHS. Thirty-three point mutations were found for the seven gene targets, six of which were predicted to have an impact on the function of the protein. The genotype/phenotype correlation was demonstrated for a loss-of-function mutation in the Phytoene desaturase gene, which is involved in carotenoid biosynthesis. Conclusions The TILLING approach was successful at providing new mutations in the genetic background of Piel de Sapo in most of the analyzed genes, even in genes for which natural variation is extremely low. This new resource will facilitate reverse genetics studies in non-climacteric melons, contributing materially to future genomic and breeding studies.

Negative predictive value of ultrasound in predicting tumor-free margins in specimen sonography

International Nuclear Information System (INIS)

Naz, S.; Hafeez, S.; Hussain, Z.; Hilal, K.

2017-01-01

Objective: To evaluate the success of ultrasound in post-excision specimen visualization, and negative predictive value of ultrasound for estimation of tumor-free margins using histopathology as the gold standard. Study Design: Cross-sectional analytical study. Place and Duration of Study: The Aga Khan University Hospital, Karachi, Pakistan, from May 2010 till January 2013. Methodology: Sonography of all breast nodules was done before and after exicision by two female radiologists with at least five years clinical experience. All surgeries were performed by the same referring breast surgeons. All nodules were non-palpable and had histopathology as well as specimen sonography performed at AKUH. Subjects were excluded, if histopathology was not available, post-procedure sonogram not done or done in another hospital and nodules that were not seen on ultrasound. After needle localization in 47 patients using ultrasound and in 7 patients using mammogram was done, sonogram was conducted in all 54 lesions. These were then assessed by ultrasound for detection of lesion and tumor-free margins in malignant lesion. Post-excision ultrasound was performed for the evaluation of lesion whether visualized or absent with localizing needle in situ, lesion dimensions, depth measurement between the superior margin of the lesion and its edge. Results: All 54 lesions were present on post-exicison scan, out of which 28 were documented as malignant and 26 as benign. Ultrasound declared all specimens as tumor-free. On histopathology, two lesions were documented as having tumor-positive margins and were proven to be invasive lobular carcinoma. Therefore, the negative predictive value of the specimen sonography for margin detection was 26/28 (92.8%). Conclusion: Ultrasound of the excised breast tumor specimen is a simple and reliable technique for confirmation of the tumor-free margins in non-palpable breast lesions. (author)

A remediation performance model for enhanced metabolic reductive dechlorination of chloroethenes in fractured clay till

DEFF Research Database (Denmark)

Manoli, Gabriele; Chambon, Julie C.; Bjerg, Poul L.

2012-01-01

A numerical model of metabolic reductive dechlorination is used to describe the performance of enhanced bioremediation in fractured clay till. The model is developed to simulate field observations of a full scale bioremediation scheme in a fractured clay till and thereby to assess remediation...

Determination of Matrix Pore Size Distribution in Fractured Clayey Till and Assessment of Matrix Migration of Dechlorinationg Bacteria

DEFF Research Database (Denmark)

Cong, Lu; Broholm, Mette Martina; Fabricius, Ida Lykke

2014-01-01

The pore structure and pore size distribution (PSD) in the clayey till matrix from three Danish field sites were investigated by image analysis to assess the matrix migration of dechlorinating bacteria in clayey till. Clayey till samples had a wide range of pore sizes, with diameters of 0.1–100 μ...

Enhanced reductive dechlorination in clay till contaminated with chlorinated solvents

DEFF Research Database (Denmark)

Damgaard, Ida

Chlorinated solvents are among the most frequently found contaminants in groundwater. In fractured media, chlorinated ethenes and ethanes are transported downwards through preferential pathways with subsequent diffusion into the sediment matrix. Due to slow back diffusion it can serve as a long...... (direct push delivery, Gl. Kongevej). Degradation of chlorinated ethenes (and ethanes) in the clay till matrix and in embedded high permeability features was investigated by high resolution sampling of intact cores combined with groundwater sampling. An integrated approach using chemical analysis...... (hydraulic fracturing with gravitational injection and direct push delivery) were therefore tested in clay till by injection of amendment-comparable tracers to investigate the possibility to overcome diffusion limitations in the low permeability matrix. The study of hydraulic fracturing demonstrated...

Variations in clast morphology for different till fractions: implementation of digital imagery

Science.gov (United States)

Dominiczak, Aleksander

2014-05-01

The form of clastic particles provides information about debris history including abrasion and transportation which are vital to geomorphological research because of its usefulness for differentiating subglacial debris form englacialy, supraglacialy and fluvially transported sediments, and for understanding subglacial processes. There are numerous attempts to clastic particles form assessment, both qualitative and quantitative and advance in technology enables the use of digital imaging and image processing in order to calculate the precise indicators of shape and roundness (small-scale surface features superimposed on shape and roundness are not a subject of this study). Computer calculations are fast, reliable and objective and its use decrease probability of errors. They are applicable to till deposits analysis and may help in understanding the processes of glacial deposition. Till deposits consist of a mixture of various fractions of sediment, where coarser and thinner grains are together activated, entrained in ice, transported, deposited and post-depositional transformed together in the same time and conditions. That implies similarity of processes acting on the particles, but not necessarily theirs effects. Physical properties of grain are of great significance for its vulnerability to acting forces. An important feature of the tills is grain size, which has a high volatility in a sample. The hypothesis of this issue suggests it is possible that different fractions of till sediment have significantly different form characteristics. Verification of the thesis is important because standardly only one fraction is selected to analysis and to draw conclusions from. Main objective is to test differences in clast morphology for different till fraction. In order to answer the research problem, the author has examined samples from a contemporary glaciated region, Nordenskiöld glacier foreland in central Spitsbergen. During the field work samples were collected from

Development and characterization of a new TILLING population of common bread wheat (Triticum aestivum L..

Directory of Open Access Journals (Sweden)

Liang Chen

Full Text Available Mutagenesis is an important tool in crop improvement. However, the hexaploid genome of wheat (Triticum aestivum L. presents problems in identifying desirable genetic changes based on phenotypic screening due to gene redundancy. TILLING (Targeting Induced Local Lesions IN Genomes, a powerful reverse genetic strategy that allows the detection of induced point mutations in individuals of the mutagenized populations, can address the major challenge of linking sequence information to the biological function of genes and can also identify novel variation for crop breeding. Wheat is especially well-suited for TILLING due to the high mutation densities tolerated by polyploids. However, only a few wheat TILLING populations are currently available in the world, which is far from satisfying the requirement of researchers and breeders in different growing environments. In addition, current TILLING screening protocols require costly fluorescence detection systems, limiting their use, especially in developing countries. We developed a new TILLING resource comprising 2610 M(2 mutants in a common wheat cultivar 'Jinmai 47'. Numerous phenotypes with altered morphological and agronomic traits were observed from the M(2 and M(3 lines in the field. To simplify the procedure and decrease costs, we use unlabeled primers and either non-denaturing polyacrylamide gels or agarose gels for mutation detection. The value of this new resource was tested using PCR with RAPD and Intron-spliced junction (ISJ primers, and also TILLING in three selected candidate genes, in 300 and 512 mutant lines, revealing high mutation densities of 1/34 kb by RAPD/ISJ analysis and 1/47 kb by TILLING. In total, 31 novel alleles were identified in the 3 targeted genes and confirmed by sequencing. The results indicate that this mutant population represents a useful resource for the wheat research community. We hope that the use of this reverse genetics resource will provide novel allelic

Engineering melon plants with improved fruit shelf life using the TILLING approach.

Directory of Open Access Journals (Sweden)

Fatima Dahmani-Mardas

2010-12-01

Full Text Available Fruit ripening and softening are key traits that have an effect on food supply, fruit nutritional value and consequently, human health. Since ethylene induces ripening of climacteric fruit, it is one of the main targets to control fruit over ripening that leads to fruit softening and deterioration. The characterization of the ethylene pathway in Arabidopsis and tomato identified key genes that control fruit ripening.To engineer melon fruit with improved shelf-life, we conducted a translational research experiment. We set up a TILLING platform in a monoecious and climacteric melon line, cloned genes that control ethylene production and screened for induced mutations that lead to fruits with enhanced shelf life. Two missense mutations, L124F and G194D, of the ethylene biosynthetic enzyme, ACC oxidase 1, were identified and the mutant plants were characterized with respect to fruit maturation. The L124F mutation is a conservative mutation occurring away from the enzyme active site and thus was predicted to not affect ethylene production and thus fruit ripening. In contrast, G194D modification occurs in a highly conserved amino acid position predicted, by crystallographic analysis, to affect the enzymatic activity. Phenotypic analysis of the G194D mutant fruit showed complete delayed ripening and yellowing with improved shelf life and, as predicted, the L124F mutation did not have an effect.We constructed a mutant collection of 4023 melon M2 families. Based on the TILLING of 11 genes, we calculated the overall mutation rate of one mutation every 573 kb and identified 8 alleles per tilled kilobase. We also identified a TILLING mutant with enhanced fruit shelf life. This work demonstrates the effectiveness of TILLING as a reverse genetics tool to improve crop species. As cucurbits are model species in different areas of plant biology, we anticipate that the developed tool will be widely exploited by the scientific community.

Adaptability of Wheat Cultivars to a Late-Planted No-Till Fallow Production System

OpenAIRE

Arron H. Carter; Stephen S. Jones; Ryan W. Higginbotham

2011-01-01

In Washington, over fifty percent of the wheat produced under rainfed conditions receives less than 300 mm of annual precipitation. Hence, a winter wheat-summer fallow cropping system has been adopted to obtain adequate moisture for winter wheat production. Current tilled fallow systems are exposed to significant soil degradation from wind and water erosion. As a result, late-planted no-till fallow systems are being evaluated to mitigate erosion concerns. The objective of this study was to ev...

Clastic dykes in over-consolidated tills: evidence for subglacial hydrofracturing at Killiney Bay, eastern Ireland

Science.gov (United States)

Rijsdijk, Kenneth F.; Owen, Geraint; Warren, William P.; McCarroll, Danny; van der Meer, Jaap J. M.

1999-11-01

A swarm of vertical gravel-filled dykes up to 6 m high and several decimetres wide, cut through an over-consolidated till at Killiney Bay. The dykes are rooted in a gravel layer and many display plumes of clastic debris ejected into the overlying sediments — `burst-out structures'. Such features have not previously been described. These clastic dykes are interpreted as the infillings of hydrofractures which formed when water pressures in the basal gravel layer exceeded the overburden pressure and tensile shear strength of the capping till. The burst-out structures extend up to 7 m from the tops of the dykes and provide strong evidence for forceful upward flow. Evidence suggests that the hydrofractures formed subglacially, probably during a minor re-advance. Their presence in Late Devensian (26-13 ka BP) tills with an Irish Sea provenance (`Irish Sea till') may have important implications for the subglacial hydrology of the last Irish Sea ice sheet. These hydrofractures cannot form in unconsolidated glacimarine sediment and their presence precludes a glacimarine origin for these deposits. They greatly affect the geotechnical properties of Irish Sea tills, in particular providing very permeable routes through otherwise impermeable layers, with important consequences in situations elsewhere in the Irish Sea basin, where they have been used as aquicludes in landfill and low-level nuclear waste disposal sites.

Carbon supply and storage in tilled and nontilled soils as influenced by cover crops and nitrogen fertilization.

Science.gov (United States)

Sainju, Upendra M; Singh, Bharat P; Whitehead, Wayne F; Wang, Shirley

2006-01-01

Soil carbon (C) sequestration in tilled and nontilled areas can be influenced by crop management practices due to differences in plant C inputs and their rate of mineralization. We examined the influence of four cover crops {legume [hairy vetch (Vicia villosa Roth)], nonlegume [rye (Secale cereale L.)], biculture of legume and nonlegume (vetch and rye), and no cover crops (or winter weeds)} and three nitrogen (N) fertilization rates (0, 60 to 65, and 120 to 130 kg N ha(-1)) on C inputs from cover crops, cotton (Gossypium hirsutum L.), and sorghum [Sorghum bicolor (L.) Moench)], and soil organic carbon (SOC) at the 0- to 120-cm depth in tilled and nontilled areas. A field experiment was conducted on Dothan sandy loam (fine-loamy, siliceous, thermic Plinthic Paleudults) from 1999 to 2002 in central Georgia. Total C inputs to the soil from cover crops, cotton, and sorghum from 2000 to 2002 ranged from 6.8 to 22.8 Mg ha(-1). The SOC at 0 to 10 cm fluctuated with C input from October 1999 to November 2002 and was greater from cover crops than from weeds in no-tilled plots. In contrast, SOC values at 10 to 30 cm in no-tilled and at 0 to 60 cm in chisel-tilled plots were greater for biculture than for weeds. As a result, C at 0 to 30 cm was sequestered at rates of 267, 33, -133, and -967 kg C ha(-1) yr(-1) for biculture, rye, vetch, and weeds, respectively, in the no-tilled plot. In strip-tilled and chisel-tilled plots, SOC at 0 to 30 cm decreased at rates of 233 to 1233 kg C ha(-1) yr(-1). The SOC at 0 to 30 cm increased more in cover crops with 120 to 130 kg N ha(-1) yr(-1) than in weeds with 0 kg N ha(-1) yr(-1), regardless of tillage. In the subtropical humid region of the southeastern United States, cover crops and N fertilization can increase the amount of C input and storage in tilled and nontilled soils, and hairy vetch and rye biculture was more effective in sequestering C than monocultures or no cover crop.

High-resolution melting curve analysis for rapid detection of mutations in a Medaka TILLING library

Directory of Open Access Journals (Sweden)

Deguchi Tomonori

2010-09-01

Full Text Available Abstract Background During the last two decades, DNA sequencing has led to the identification of numerous genes in key species; however, in most cases, their functions are still unknown. In this situation, reverse genetics is the most suitable method to assign function to a gene. TILLING (Targeting Induced Local Lesions IN Genomes is a reverse-genetic strategy that combines random chemical mutagenesis with high-throughput discovery of the induced mutations in target genes. The method has been applied to a variety of plant and animal species. Screening of the induced mutations is the most important step in TILLING. Currently, direct sequencing or nuclease-mediated screening of heteroduplexes is widely used for detection of mutations in TILLING. Both methods are useful, but the costs are substantial and turnaround times are relatively long. Thus, there is a need for an alternative method that is of higher throughput and more cost effective. Results In this study, we developed a high resolution melting (HRM assay and evaluated its effectiveness for screening ENU-induced mutations in a medaka TILLING library. We had previously screened mutations in the p53 gene by direct sequencing. Therefore, we first tested the efficiency of the HRM assay by screening mutations in p53, which indicated that the HRM assay is as useful as direct sequencing. Next, we screened mutations in the atr and atm genes with the HRM assay. Nonsense mutations were identified in each gene, and the phenotypes of these nonsense mutants confirmed their loss-of-function nature. Conclusions These results demonstrate that the HRM assay is useful for screening mutations in TILLING. Furthermore, the phenotype of the obtained mutants indicates that medaka is an excellent animal model for investigating genome stability and gene function, especially when combined with TILLING.

Production of a high-efficiency TILLING population through polyploidization.

Science.gov (United States)

Tsai, Helen; Missirian, Victor; Ngo, Kathie J; Tran, Robert K; Chan, Simon R; Sundaresan, Venkatesan; Comai, Luca

2013-04-01

Targeting Induced Local Lesions in Genomes (TILLING) provides a nontransgenic method for reverse genetics that is widely applicable, even in species where other functional resources are missing or expensive to build. The efficiency of TILLING, however, is greatly facilitated by high mutation density. Species vary in the number of mutations induced by comparable mutagenic treatments, suggesting that genetic background may affect the response. Allopolyploid species have often yielded higher mutation density than diploids. To examine the effect of ploidy, we autotetraploidized the Arabidopsis (Arabidopsis thaliana) ecotype Columbia, whose diploid has been used for TILLING extensively, and mutagenized it with 50 mm ethylmethane sulfonate. While the same treatment sterilized diploid Columbia, the tetraploid M1 plants produced good seed. To determine the mutation density, we searched 528 individuals for induced mutations in 15 genes for which few or no knockout alleles were previously available. We constructed tridimensional pools from the genomic DNA of M2 plants, amplified target DNA, and subjected them to Illumina sequencing. The results were analyzed with an improved version of the mutation detection software CAMBa that accepts any pooling scheme. This small population provided a rich resource with approximately 25 mutations per queried 1.5-kb fragment, including on average four severe missense and 1.3 truncation mutations. The overall mutation density of 19.4 mutations Mb(-1) is 4 times that achieved in the corresponding diploid accession, indicating that genomic redundancy engenders tolerance to high mutation density. Polyploidization of diploids will allow the production of small populations, such as less than 2,000, that provide allelic series from knockout to mild loss of function for virtually all genes.

The Use of TILLING Technique to Detect Mutations and genetic diversity in Potato

International Nuclear Information System (INIS)

Elias, R; Al-Safadi, B; Till, B

2008-01-01

TILLING technique has been used, for the first time, to detect genetic variation, at the molecular level, among potato mutants (induced by gamma irradiation) and genetic diversity among 3 potato cultivars. Three potato mutant lines (every mutant represents a cultivar) tolerant to salinity have been used along with their controls. Three primer pairs were designed with the help of Potato Genome Sequencing Consortium on the web and were evaluated using agarose gel then sequencing. Primer pairs passing these tests were fluorescently labeled. Li-Cor based TILLING was applied using 2 forward primers one of them is labeled and 2 reverse primers one of them is labeled. The results have shown the success of using this technique on potato (tetraploid species) where the average density of nucleotide polymorphisms per sample was 16 polymorphisms per 1 kb. The optimal concentration was also determined between 0.1 and 1 ng/ul for potato genomic DNAs to be used in Li-Cor based TILLING assays. (author)

Wheat Cultivar Performance and Stability between No-Till and Conventional Tillage Systems in the Pacific Northwest of the United States

Directory of Open Access Journals (Sweden)

Arron H. Carter

2013-02-01

Full Text Available In Washington, over fifty percent of the wheat produced under rainfed conditions receives less than 300 mm of annual precipitation. Hence, a winter wheat-summer fallow cropping system has been established to obtain adequate moisture for winter wheat production. Current tilled fallow systems receive significant soil erosion through both wind and water. As a result, no-till chemical fallow systems are being adopted to mitigate erosion concerns. The objective of this study was to evaluate current Pacific Northwest cultivars under no-till chemical fallow and tilled fallow systems to identify cultivars adapted to a late-planted no-till system. Twenty-one cultivars were planted in a split-plot design with fallow type as the main plot and genotype as the sub-plot. Four replications were planted at two locations over three years. Data was collected on heading date, grain yield and grain volume weight. Analysis of variance was conducted on data from each year and location. Results were significant for all traits. Cultivars in the late-planted no-till system yielded an average of 39% less than the tilled fallow system. It is evident that cultivars vary in their adaptability and yield stability across production systems. Chukar and Eltan displayed the highest levels of yield stability, and growers who wish to plant winter wheat in a late-planted no-till system may benefit from choosing these cultivars.

Performance of full scale enhanced reductive dechlorination in clay till

DEFF Research Database (Denmark)

Damgaard, Ida; Bjerg, Poul Løgstrup; Jacobsen, Carsten S.

2013-01-01

At a low permeability clay till site contaminated with chlorinated ethenes (Gl. Kongevej, Denmark), enhanced reductive dechlorination (ERD) was applied by direct push injection of molasses and dechlorinating bacteria. The performance was investigated by long-term groundwater monitoring, and after 4...

Millennials och baby boomers attityder till fake news : Generationernas upplevelser av nyhetsmediers sanningshalt

OpenAIRE

Adolfsson, Claes; Strömberg, Markus; Stenberg, John

2017-01-01

Syftet med denna uppsats var att ta reda på generationerna millennials och baby boomers inställning till mediernas sanningshalt och politiska neutralitet. Detta gjordes med hjälp av följande frågeställningar: Vilka attityder och vilken inställning har millennials och baby boomers till nyhetsmediernas sanningshalt? Finns skillnader och likheter kvar när vi väger in variablerna kön och politiskt ställningstagande?   För att definiera generationerna använde vi oss av Cliff Zukins generationsteor...

Measurement of saturated hydraulic conductivity in fine-grained glacial tills in Iowa: Comparison of in situ and laboratory methods

Science.gov (United States)

Bruner, D. Roger; Lutenegger, Alan J.

1994-01-01

Nested-standpipe and vibrating-wire piezometers were installed in Pre-Illinoian Wolf Creek and Albernett formations at the Eastern Iowa Till Hydrology Site located in Linn County, Iowa. These surficial deposits are composed of fine-grained glacial diamicton (till) with occasional discontinuous lenses of sand and silt. They overlie the Silurian (dolomite) aquifer which provides private, public, and municipal drinking water supplies in the region. The saturated hydraulic conductivity of the Wolf Creek Formation was investigated in a sub-area of the Eastern Iowa Till Hydrology Site. Calculations of saturated hydraulic conductivity were based on laboratoryflexible-wall permeameter tests, bailer tests, and pumping test data. Results show that bulk hydraulic conductivity increases by several orders of magnitude as the tested volume of till increases. Increasing values of saturated hydraulic conductivity at larger spatial scales conceptually support a double-porosity flow model for this till.

ESR dating of glacial tills of Baishuihe river on the southern slope of Lenglongling in the eastern part of Qilian Mountains

International Nuclear Information System (INIS)

Zhao Jingdong; Zhou Shangzhe; Shi Zhengtao; Zhang Shiqiang; Cui Jianxin; Xu Liubing; Ye Yuguang

2001-01-01

Baishuihe River is a tributary of Datong River, located on the southern slope of Lenglongling in the eastern part of the Qilian Mountains. An integral end till remains at the entrance of the valley. There is a push moraine in the till section. Three samples were derived from this section. Two samples were collected at the front of the push moraine and another sample (near the push moraine) collected from the rear of it, ESR ages were 73.0 ka, 55.8 ka, 36.7 ka respectively. The ESR ages being consistent with the relationship of deposits. The ages before the push moraine were correlated to the deep-sea oxygen isotope stage 4 within 10% deviation. Based on them, the authors could determine the till before the push moraine were formed in the early period of Last Glaciation. Comparing the ESR age of LS-5 with the results of previous 14 C, the authors found that the ESR age was older. Through the error correction, the authors concluded: the existing push moraine distorted the till around it, mixing the super-glacial till, englacial till and subglacial till together. The authors considered: the main reason influencing the ESR age was that the englacial till and the subglacial till were not exposed completely before they deposited. Although the result of LS-5 was older than the previous 14 C, combining the ESR age and the relationship of deposit and the existing 14 C ages, the authors inferred that the rear of the push moraine was deposited in the later period of the last glaciation and was correlated to the deep-sea oxygen isotope stage 2. At the same time, the conclusion once again proved the previous scholars' conclusion. This shows the ESR technique may be applied to glacial till dating

Magnetic fabric of sheared till: A strain indicator for evaluating the bed deformation model of glacier flow

Science.gov (United States)

Hooyer, T.S.; Iverson, N.R.; Lagroix, F.; Thomason, J.F.

2008-01-01

Wet-based portions of ice sheets may move primarily by shearing their till beds, resting in high sediment fluxes and the development of subglacial landforms. This model of glacier movement, which requires high bed shear strains, can be tested using till microstructural characteristics that evolve during till deformation. Here we examine the development of magnetic fabric using a ring shear device to defom two Wisconsin-age basal tills to shear strains as high as 70. Hysteresis experiments and the dependence of magnetic susceptibility of these tills on temperature demonstrate that anisotropy of magnetic susceptibility (AMS) develops during shear due to the rotation of primarily magnetite particles that are silt sized or smaller. At moderate shear strains (???6-25), principal axes of maximum magnetic susceptibility develop a strong fabric (S1 eignevalues of 0.83-0.96), without further strengthening at higher strains, During deformation, directions of maximum susceptibility cluster strongly in the direction of shear and plunge 'up-glacier,' consistent with the behavior of pebbles and sand particles studied in earlier experiments. In contrast, the magnitude of AMS does not vary systematically with strain and is small relative to its variability among samples; this is because most magnetite grains are contained as inclusions in larger particles and hence do not align during shear. Although processes other than pervasive bed deformation may result in strong flow parallel fabrics, AMS fabrics provide a rapid and objective means of identifying basal tills that have not been sheared sufficiently to be compatible with the bed deformation model. Copyright 2008 by the American Geophysical Union.

Improving the Hydraulic Performance of Stormwater Infiltration Systems in Clay Tills

DEFF Research Database (Denmark)

Bockhorn, Britta

investigations on two typical Danish clay till sites, and one modeling study with the integrated surface water and groundwater model HydroGeoSphere. The saturated hydraulic conductivity (Ksat) is the most critical soil physical parameter when it comes to sizing stormwater infiltration systems. In the first study......, different field methods for Ksat estimation, the double ring infiltrometer, the Guelph permeameter and falling head infiltration tests in a small excavation, were compared and evaluated for their capability to return realistic Ksat values in tills. The double ring infiltrometer and the Guelph permeameter...... represent suitable methods for sizing stormwater infiltration systems if measurements are combined with geological knowledge from maps of near-surface deposits and borehole descriptions. If space allows, the more invasive infiltration tests in a small excavation are recommended, because measurements...

Landscape-scale distribution and persistence of genetically modified oilseed rape (Brassica napus) in Manitoba, Canada.

Science.gov (United States)

Knispel, Alexis L; McLachlan, Stéphane M

2010-01-01

Genetically modified herbicide-tolerant (GMHT) oilseed rape (OSR; Brassica napus L.) was approved for commercial cultivation in Canada in 1995 and currently represents over 95% of the OSR grown in western Canada. After a decade of widespread cultivation, GMHT volunteers represent an increasing management problem in cultivated fields and are ubiquitous in adjacent ruderal habitats, where they contribute to the spread of transgenes. However, few studies have considered escaped GMHT OSR populations in North America, and even fewer have been conducted at large spatial scales (i.e. landscape scales). In particular, the contribution of landscape structure and large-scale anthropogenic dispersal processes to the persistence and spread of escaped GMHT OSR remains poorly understood. We conducted a multi-year survey of the landscape-scale distribution of escaped OSR plants adjacent to roads and cultivated fields. Our objective was to examine the long-term dynamics of escaped OSR at large spatial scales and to assess the relative importance of landscape and localised factors to the persistence and spread of these plants outside of cultivation. From 2005 to 2007, we surveyed escaped OSR plants along roadsides and field edges at 12 locations in three agricultural landscapes in southern Manitoba where GMHT OSR is widely grown. Data were analysed to examine temporal changes at large spatial scales and to determine factors affecting the distribution of escaped OSR plants in roadside and field edge habitats within agricultural landscapes. Additionally, we assessed the potential for seed dispersal between escaped populations by comparing the relative spatial distribution of roadside and field edge OSR. Densities of escaped OSR fluctuated over space and time in both roadside and field edge habitats, though the proportion of GMHT plants was high (93-100%). Escaped OSR was positively affected by agricultural landscape (indicative of cropping intensity) and by the presence of an

Application of the surface azimuthal electrical resistivity survey method to determine patterns of regional joint orientation in glacial tills

Science.gov (United States)

Carlson, D.

2010-01-01

Joints within unconsolidated material such as glacial till can be primary avenues for the flow of electrical charge, water, and contaminants. To facilitate the siting and design of remediation programs, a need exists to map anisotropic distribution of such pathways within glacial tills by determining the azimuth of the dominant joint set. The azimuthal survey method uses standard resistivity equipment with a Wenner array rotated about a fixed center point at selected degree intervals that yields an apparent resistivity ellipse. From this ellipse, joint set orientation can be determined. Azimuthal surveys were conducted at 21 sites in a 500-km2 (193 mi2) area around Milwaukee, Wisconsin, and more specifically, at sites having more than 30 m (98 ft) of glacial till (to minimize the influence of underlying bedrock joints). The 26 azimuthal surveys revealed a systematic pattern to the trend of the dominant joint set within the tills, which is approximately parallel to ice flow direction during till deposition. The average orientation of the joint set parallel with the ice flow direction is N77??E and N37??E for the Oak Creek and Ozaukee tills, respectively. The mean difference between average direct observation of joint set orientations and average azimuthal resistivity results is 8??, which is one fifth of the difference of ice flow direction between the Ozaukee and Oak Creek tills. The results of this study suggest that the surface azimuthal electrical resistivity survey method used for local in situ studies can be a useful noninvasive method for delineating joint sets within shallow geologic material for regional studies. Copyright ?? 2010 The American Association of Petroleum Geologists/Division of Environmental Geosciences. All rights reserved.

No-till systems on the Chequen Farm in Chile: A success story in bringing practice and science together

Directory of Open Access Journals (Sweden)

D. Reicosky

2014-03-01

Full Text Available No-till cropping systems provide an opportunity to protect the soil from erosion, while contemporaneously maintaining high yields and contributing to global food security. The historical aspects and the remarkable development of no-till systems on the Chequen Farm in Chile are reviewed. The adoption of no-till over the last 40 years has been a major turning point in reducing the devastating effects of soil erosion and a model for the evolution of sustainable crop production in highly erodible terrain in other parts of the world. The process of adoption of no-till systems in severely eroded foothills of Chile is described, as well as the environmental benefits and the sustainability of the system. The practical aspects of these developments are supported by scientific literature where appropriate, illustrating the value and coincident knowledge gained when combining analogue observations and information with scientific principles.

DHPLC technology for high-throughput detection of mutations in a durum wheat TILLING population.

Science.gov (United States)

Colasuonno, Pasqualina; Incerti, Ornella; Lozito, Maria Luisa; Simeone, Rosanna; Gadaleta, Agata; Blanco, Antonio

2016-02-17

Durum wheat (Triticum turgidum L.) is a cereal crop widely grown in the Mediterranean regions; the amber grain is mainly used for the production of pasta, couscous and typical breads. Single nucleotide polymorphism (SNP) detection technologies and high-throughput mutation induction represent a new challenge in wheat breeding to identify allelic variation in large populations. The TILLING strategy makes use of traditional chemical mutagenesis followed by screening for single base mismatches to identify novel mutant loci. Although TILLING has been combined to several sensitive pre-screening methods for SNP analysis, most rely on expensive equipment. Recently, a new low cost and time saving DHPLC protocol has been used in molecular human diagnostic to detect unknown mutations. In this work, we developed a new durum wheat TILLING population (cv. Marco Aurelio) using 0.70-0.85% ethyl methane sulfonate (EMS). To investigate the efficiency of the mutagenic treatments, a pilot screening was carried out on 1,140 mutant lines focusing on two target genes (Lycopene epsilon-cyclase, ε-LCY, and Lycopene beta-cyclase, β-LCY) involved in carotenoid metabolism in wheat grains. We simplify the heteroduplex detection by two low cost methods: the enzymatic cleavage (CelI)/agarose gel technique and the denaturing high-performance liquid chromatography (DHPLC). The CelI/agarose gel approach allowed us to identify 31 mutations, whereas the DHPLC procedure detected a total of 46 mutations for both genes. All detected mutations were confirmed by direct sequencing. The estimated overall mutation frequency for the pilot assay by the DHPLC methodology resulted to be of 1/77 kb, representing a high probability to detect interesting mutations in the target genes. We demonstrated the applicability and efficiency of a new strategy for the detection of induced variability. We produced and characterized a new durum wheat TILLING population useful for a better understanding of key gene functions

Glyphosate Dissipation in Different Soils Under No-Till and Conventional Till

Science.gov (United States)

Okada, Elena; Costa, Jose Luis; Francisco, Bedmar

2017-04-01

Glyphosate is the most used herbicide in Argentina, accounting for 62% of the commercialized pesticides in the market. It is used as a weed controller in chemical fallow under no-till systems, and it is also applied in various genetically modified crops (e.g. soybean, corn, cotton). Though it has a high solubility in water, it tends to adsorb and accumulate in agricultural soils. The description of glyphosate biodegradation in soils with a long term history under agricultural practices is of interest. The main objectives of this work were to compare the dissipation of glyphosate and the accumulation of its metabolite aminomethylphosphonic acid (AMPA) over time in three soils from Argentina. The studied soils belong to areas of high agronomic land use and different edaphoclimatic conditions, situated in Manfredi (MAN), Pergamino (PER) and Paraná (PAR). Soil samples were taken from long-term field trials with a history of more than 16 years under no-till and conventional tillage management. To study glyphosate dissipation in soil under controlled laboratory conditions, 400 g of dry soil sample were placed in 1.5 L flasks. A dose corresponding to 6 L ha-1 of commercial glyphosate ATANOR II® (35.6 % a.i.) was applied on day 0. The dose applied was equivalent to a final concentration in soil of 4000 μg Kg-1 of active ingredient. The moisture of the soil samples was kept at 60 % of the field capacity. Samples were incubated in the dark at a constant temperature of 22°C ± 1°C. A sub-sample of 5 g was taken from each flask at day 0 (after application), 1, 3, 7, 15, 20, 28, 44 and 62. Glyphosate and AMPA in soil samples was extracted with a strong basic solution (100 mM Na2B4O7•10H2O/ 100 mM K3PO4, pH=9) and then derivitazed with FMOC-Cl. Detection and quantification of the compounds was performed by ultra-performance liquid chromatography coupled with a mass spectrometer (UPLC MS/MS). The results showed that forty percent of the applied glyphosate was degraded

Feasibility and Performance of Full-Scale In-situ Remediation of TCE by ERD in Clay Tills

DEFF Research Database (Denmark)

Broholm, Mette Martina; Damgaard, Ida; Chambon, Julie Claire Claudia

The feasibility and performance of full-scale applications of ERD in clay tills were investigated in a research project including 2 sites in Denmark, which have been undergoing remediation since 2006. At both sites organic substrates and bioaugmentation cultures have been injected in TCE-contamin......The feasibility and performance of full-scale applications of ERD in clay tills were investigated in a research project including 2 sites in Denmark, which have been undergoing remediation since 2006. At both sites organic substrates and bioaugmentation cultures have been injected in TCE......-contaminated clay till. An integrated investigative approach consisting of water and clay core sample analysis, including stable isotopes and specific degraders, as well as analysis for chlorinated solvents, degradation products, donor fermentation products and redox-sensitive parameters combined with modelling has...

A remediation performance model for enhanced metabolic reductive dechlorination of chloroethenes in fractured clay till

Science.gov (United States)

Manoli, Gabriele; Chambon, Julie C.; Bjerg, Poul L.; Scheutz, Charlotte; Binning, Philip J.; Broholm, Mette M.

2012-04-01

A numerical model of metabolic reductive dechlorination is used to describe the performance of enhanced bioremediation in fractured clay till. The model is developed to simulate field observations of a full scale bioremediation scheme in a fractured clay till and thereby to assess remediation efficiency and timeframe. A relatively simple approach is used to link the fermentation of the electron donor soybean oil to the sequential dechlorination of trichloroethene (TCE) while considering redox conditions and the heterogeneous clay till system (clay till matrix, fractures and sand stringers). The model is tested on lab batch experiments and applied to describe sediment core samples from a TCE-contaminated site. Model simulations compare favorably to field observations and demonstrate that dechlorination may be limited to narrow bioactive zones in the clay matrix around fractures and sand stringers. Field scale simulations show that the injected donor is expected to be depleted after 5 years, and that without donor re-injection contaminant rebound will occur in the high permeability zones and the mass removal will stall at 18%. Long remediation timeframes, if dechlorination is limited to narrow bioactive zones, and the need for additional donor injections to maintain dechlorination activity may limit the efficiency of ERD in low-permeability media. Future work should address the dynamics of the bioactive zones, which is essential to understand for predictions of long term mass removal.

Identification of chlorinated solvents degradation zones in clay till by high resolution chemical, microbial and compound specific isotope analysis

DEFF Research Database (Denmark)

Damgaard, Ida; Bjerg, Poul Løgstrup; Bælum, Jacob

2013-01-01

subsampling of the clay till cores. The study demonstrates that an integrated approach combining chemical analysis, molecular microbial tools and compound specific isotope analysis (CSIA) was required in order to document biotic and abiotic degradations in the clay till system. © 2013 Elsevier B.V.......The degradation of chlorinated ethenes and ethanes in clay till was investigated at a contaminated site (Vadsby, Denmark) by high resolution sampling of intact cores combined with groundwater sampling. Over decades of contamination, bioactive zones with degradation of trichloroethene (TCE) and 1...

Biofuel production and climate mitigation potential from marginal lands in US North Central region

Science.gov (United States)

Gelfand, I.; Sahajpal, R.; Zhang, X.; Izaurralde, R. C.; Robertson, G. P.

2010-12-01

An ever-increasing demand for liquid fuels, amidst concerns of anthropogenic impacts on the environment and fossil fuels availability, has spurred a strong interest in the development of agriculturally-based renewable energy sources. However, increasing demand for food as well as direct and indirect effects on land use, have raised concerns about reliance on grain-based ethanol and shifted research towards the direction of cellulosic feedstocks. In order to understand the future possibility for using agricultural systems for bio-fuel production, we present here a full greenhouse gas (GHG) balance of six potential sources of cellulosic feedstocks production. From 1991 to 2008, we measured GHGs sinks and sources in cropped and nearby unmanaged ecosystems in SW Michigan. The measurements included soil fluxes of GHGs (N2O and CH4), soil organic carbon concentration change, agronomic practices data, and biomass yields. We analyzed two types of intensively managed annual cropping systems under corn-soybean-wheat rotation (conventional tillage and no till), two perennial systems (alfalfa and poplar plantation), and one successional system. The use of agricultural residues for biofuel feedstock from conventionally-tilled crops had the lowest climate stabilization potential (-9 ±13 gCO2e m-2 y-1). In contrast, biomass collected from a successional system fertilized with N at123 kg ha-1y-1 showed the highest climate stabilization potential (-749 ±30 gCO2e m-2 y-1). We used our results to parameterize the EPIC model, which, together with GIS analysis was used to scale up the biomass productivity of the best environmentally performing systems to the marginal lands of the 10-state U.S. North Central region. Assuming 80 km as the maximum distance for road haulage to the biorefinery from the field, we identified 32 potential biorefinery placements each capable of supplying sufficient feedstock to produce at least 133 × 106 L y-1. In total, ethanol production from marginal

Long-term use of cover crops and no-till shift soil microbial community life strategies in agricultural soil

Science.gov (United States)

Mitchell, Jeffrey; Scow, Kate

2018-01-01

Reducing tillage and growing cover crops, widely recommended practices for boosting soil health, have major impacts on soil communities. Surprisingly little is known about their impacts on soil microbial functional diversity, and especially so in irrigated Mediterranean ecosystems. In long-term experimental plots at the West Side Research and Extension Center in California’s Central Valley, we characterized soil microbial communities in the presence or absence of physical disturbance due to tillage, in the presence or absence of cover crops, and at three depths: 0–5, 5–15 and 15–30 cm. This characterization included qPCR for bacterial and archaeal abundances, DNA sequencing of the 16S rRNA gene, and phylogenetic estimation of two ecologically important microbial traits (rRNA gene copy number and genome size). Total (bacterial + archaeal) diversity was higher in no-till than standard till; diversity increased with depth in no-till but decreased with depth in standard till. Total bacterial numbers were higher in cover cropped plots at all depths, while no-till treatments showed higher numbers in 0–5 cm but lower numbers at lower depths compared to standard tillage. Trait estimates suggested that different farming practices and depths favored distinctly different microbial life strategies. Tillage in the absence of cover crops shifted microbial communities towards fast growing competitors, while no-till shifted them toward slow growing stress tolerators. Across all treatment combinations, increasing depth resulted in a shift towards stress tolerators. Cover crops shifted the communities towards ruderals–organisms with wider metabolic capacities and moderate rates of growth. Overall, our results are consistent with decreasing nutrient availability with soil depth and under no-till treatments, bursts of nutrient availability and niche homogenization under standard tillage, and increases in C supply and variety provided by cover crops. Understanding how

Farm-level economics of innovative tillage technologies: the case of no-till in the Altai Krai in Russian Siberia.

Science.gov (United States)

Bavorova, Miroslava; Imamverdiyev, Nizami; Ponkina, Elena

2018-01-01

In the agricultural Altai Krai in Russian Siberia, soil degradation problems are prevalent. Agronomists recommend "reduced tillage systems," especially no-till, as a sustainable way to cultivate land that is threatened by soil degradation. In the Altai Krai, less is known about the technologies in practice. In this paper, we provide information on plant cultivation technologies used in the Altai Krai and on selected factors preventing farm managers in this region from adopting no-till technology based on our own quantitative survey conducted across 107 farms in 2015 and 2016. The results of the quantitative survey show that farm managers have high uncertainty regarding the use of no-till technology including its economics. To close this gap, we provide systematic analysis of factors influencing the economy of the plant production systems by using a farm optimization model (linear programming) for a real farm, together with expert estimations. The farm-specific results of the optimization model show that under optimal management and climatic conditions, the expert Modern Canadian no-till technology outperforms the farm min-till technology, but this is not the case for suboptimal conditions with lower yields.

Thin-layer effects in glaciological seismic amplitude-versus-angle (AVA analysis: implications for characterising a subglacial till unit, Russell Glacier, West Greenland

Directory of Open Access Journals (Sweden)

A. D. Booth

2012-08-01

Full Text Available Seismic amplitude-versus-angle (AVA methods are a powerful means of quantifying the physical properties of subglacial material, but serious interpretative errors can arise when AVA is measured over a thinly-layered substrate. A substrate layer with a thickness less than 1/4 of the seismic wavelength, λ, is considered "thin", and reflections from its bounding interfaces superpose and appear in seismic data as a single reflection event. AVA interpretation of subglacial till can be vulnerable to such thin-layer effects, since a lodged (non-deforming till can be overlain by a thin (metre-scale cap of dilatant (deforming till. We assess the potential for misinterpretation by simulating seismic data for a stratified subglacial till unit, with an upper dilatant layer between 0.1–5.0 m thick (λ / 120 to > λ / 4, with λ = 12 m. For dilatant layers less than λ / 6 thick, conventional AVA analysis yields acoustic impedance and Poisson's ratio that indicate contradictory water saturation. A thin-layer interpretation strategy is proposed, that accurately characterises the model properties of the till unit. The method is applied to example seismic AVA data from Russell Glacier, West Greenland, in which characteristics of thin-layer responses are evident. A subglacial till deposit is interpreted, having lodged till (acoustic impedance = 4.26±0.59 × 10⁶ kg m⁻² s⁻¹ underlying a water-saturated dilatant till layer (thickness < 2 m, Poisson's ratio ~ 0.5. Since thin-layer considerations offer a greater degree of complexity in an AVA interpretation, and potentially avoid misinterpretations, they are a valuable aspect of quantitative seismic analysis, particularly for characterising till units.

SEEMLA: 'Filling the gap' - The Future of bioenergy in the EU and the role of biomass from marginal lands

Science.gov (United States)

Baumgarten, Wibke; Kerckow, Birger

2017-04-01

The main objective of the H2020 funded EU project SEEMLA is the establishment of suitable innovative land-use strategies for a sustainable production of plant-based energy on marginal lands while improving general ecosystem services. In the context of the German Renewable Energy Sources Act (EEG, Erneuerbare Energien Gesetz) and the European Common Agricultural Policy (CAP) a concept should be developed with SEEMLA for a sustainable use of domestic biomass in order to be able to 'fill the gap' of the future demand in renewable resources as an energy source till 2050. The project partner countries are Italy, the Ukraine and Greece besides Germany.

Creating Carbon Offsets in Agriculture through No-Till Cultivation. A Meta-Analysis of Costs and Carbon Benefits

International Nuclear Information System (INIS)

Manley, J.; Van Kooten, G.C.; Moeltner, K.; Johnson, D.W.

2005-01-01

Carbon terrestrial sinks are often seen as a low-cost alternative to fuel switching and reduced fossil fuel use for lowering atmospheric CO2. To determine whether this is true for agriculture, one meta-regression analysis (52 studies, 536 observations) examines the costs of switching from conventional tillage to no-till, while another (51 studies, 374 observations) compares carbon accumulation under the two practices. Costs per ton of carbon uptake are determined by combining the two results. The viability of agricultural carbon sinks is found to vary by region and crop, with no-till representing a low-cost option in some regions (costs of less than $10 per tC), but a high-cost option in others (costs of 100-$400 per tC). A particularly important finding is that no-till cultivation may store no carbon at all if measurements are taken at sufficient depth. In some circumstances no-till cultivation may yield a triple dividend of carbon storage, increased returns and reduced soil erosion, but in many others creating carbon offset credits in agricultural soils is not cost effective because reduced tillage practices store little or no carbon

Radon content in Danish till deposits: relationship with redox conditions and age

International Nuclear Information System (INIS)

Gravesen, P.; Roll Jakobsen, P.

2010-01-01

This paper presents some results concerning the radon content and emanation rates in different Danish till deposits of Saalian and Weichselian age from a study carried out by the Geological Survey of Denmark and Greenland (GEUS). (LN)

Pesticide and transformation product detections and age-dating relations from till and sand deposits

Science.gov (United States)

Warner, K.L.; Morrow, W.S.

2007-01-01

Pesticide and transformation product concentrations and frequencies in ground water from areas of similar crop and pesticide applications may vary substantially with differing lithologies. Pesticide analysis data for atrazine, metolachlor, alachlor, acetochlor, and cyanazine and their pesticide transformation products were collected at 69 monitoring wells in Illinois and northern Indiana to document occurrence of pesticides and their transformation products in two agricultural areas of differing lithologies, till, and sand. The till is primarily tile drained and has preferential fractured flow, whereas the sand primarily has surface water drainage and primary porosity flow. Transformation products represent most of the agricultural pesticides in ground water regardless of aquifer material - till or sand. Transformation products were detected more frequently than parent pesticides in both the till and sand, with metolachlor ethane sulfonic acid being most frequently detected. Estimated ground-water recharge dates for the sand were based on chlorofluorocarbon analyses. These age-dating data indicate that ground water recharged prior to 1990 is more likely to have a detection of a pesticide or pesticide transformation product. Detections were twice as frequent in ground water recharged prior to 1990 (82%) than in ground water recharged on or after 1990 (33%). The highest concentrations of atrazine, alachlor, metolachlor, and their transformation products, also were detected in samples from ground water recharged prior to 1990. These age/pesticide detection relations are opposite of what would normally be expected, and may be the result of preferential flow and/or ground-water mixing between aquifers and aquitards as evident by the detection of acetochlor transformation products in samples with estimated ground-water ages predating initial pesticide application. ?? 2007 American Water Resources Association.

The impact of bioaugmentation on dechlorination kinetics and on microbial dechlorinating communities in subsurface clay till

DEFF Research Database (Denmark)

Bælum, Jacob; Scheutz, Charlotte; Chambon, Julie Claire Claudia

2014-01-01

A molecular study on how the abundance of the dechlorinating culture KB-1 affects dechlorination rates in clay till is presented. DNA extracts showed changes in abundance of specific dechlorinators as well as their functional genes. Independently of the KB-1 added, the microbial dechlorinator abu......, highlights the ecological behavior of KB-1 in clay till, and reinforces the importance of using multiple functional genes as biomarkers for reductive dechlorination. © 2013 Elsevier Ltd. All rights reserved....

Passive microwave remote sensing of soil moisture - The effect of tilled row structure

Science.gov (United States)

Wang, J. R.; Newton, R. W.; Rouse, J. W., Jr.

1980-01-01

The tilled row structure in agricultural fields is one of the important factors affecting observations of microwave emission from such fields. Measurements of this effect were performed with L-band and X-band radiometers mounted on a mobile truck on a bare 40 m x 45 m row tilled field; the soil moisture content during measurements ranged from 10 to 30% by dry weight. Results showed that the variations of the antenna temperatures with incident angle changed with the azimuth angle measured from the row direction. It is found that the observed difference between horizontally and vertically polarized antenna temperatures is due to the change in the local angle of field emission within the antenna field of view caused by the large-scale row structure.

Sorption of chlorinated solvents and degradation products on natural clayey tills

DEFF Research Database (Denmark)

Cong, Lu; Bjerg, Poul Løgstrup; Zhang, Fengjun

2011-01-01

linear, but fitted by Freundlich isotherms slightly better over the entire concentration range. For chloroethylenes, tetrachloroethylene (PCE) was most strongly sorbed to the clayey till samples (Kd=0.84–2.45Lkg−1), followed by trichloroethylene (TCE, Kd=0.62–0.96Lkg−1), cis-dichloroethylene (cis-DCE, Kd...

Cover Crop (Rye) and No-Till System in Wisconsin

OpenAIRE

Alföldi, Thomas

2014-01-01

Erin Silva, University of Wisconsin, describes an organic no-till production technique using rye as cover crop to suppress weeds in the following production season. Using a roller-crimper, the overwintering rye is terminated at the time of cash crop planting, leaving a thick mat of plant residue on the soil surface. Soybeans are sown directly into the cover crop residue, allowing the cash crop to emerge through the terminated cover crop while suppressing weeds throughout the season. W...

Effect of Margin Designs on the Marginal Adaptation of Zirconia Copings.

Science.gov (United States)

Habib, Syed Rashid; Al Ajmi, Mohammed Ginan; Al Dhafyan, Mohammed; Jomah, Abdulrehman; Abualsaud, Haytham; Almashali, Mazen

2017-09-01

The aim of this in vitro study was to investigate the effect of Shoulder versus Chamfer margin design on the marginal adaptation of zirconia (Zr) copings. 40 extracted molar teeth were mounted in resin and prepared for zirconia crowns with two margin preparation designs (20=Shoulder and 20=Chamfer). The copings were manufactured by Cercon® (DeguDent GmbH, Germany) using the CAD/CAM system for each tooth. They were tried on each tooth, cemented, thermocycled, re-embedded in resin and were subsequently cross sectioned centrally into two equal mesial and distal halves. They were examined under electron microscope at 200 X magnification and the measurements were recorded at 5 predetermined points in micrometers (µm). The o verall mean marginal gap for the two groups was found to be 206.98+42.78µm with Shoulder margin design (Marginal Gap=199.50+40.72µm) having better adaptation compared to Chamfer (Marginal Gap=214.46+44.85µm). The independent-samples t-test showed a statistically non-significant difference (p=.113) between the means of marginal gap for Shoulder and Chamfer margin designs and the measurements were recorded at 5 predetermined points for the two groups. The Chamfer margin design appeared to offer the same adaptation results as the Shoulder margin design.

Application of the X-ray fluorescence analysis and X-ray diffraction in geochemical studies of the Pleistocene tills from Holy Cross Mountains

International Nuclear Information System (INIS)

Kubala-Kukuś, A.; Ludwikowska-Kedzia, M.; Banaś, D.; Braziewicz, J.; Majewska, U.; Pajek, M.; Wudarczyk-Moćko, J.

2013-01-01

X-ray fluorescence analysis methods (wavelength dispersive X-ray fluorescence analysis (WDXRF) and total reflection X-ray fluorescence (TXRF)) and X-ray powder diffraction (XRPD) have been applied in complementary geochemical studies of the Pleistocene till samples. The XRPD technique gave information about the mineral composition of the analyzed samples while the WDXRF and TXRF studies allowed the fast elemental analysis. The till samples were collected from different regions of Holy Cross Mountains (located in central Poland) which are still not unambiguously described in the context of the geochemical studies of the Quaternary sediments. The analysis was concentrated on the geochemical composition of the till samples both for materials occurring on the surface (characterized by continuous weathering processes) and for samples taken from core borehole. The overriding purpose of these studies is determination of the local lithotype of the tills and its lithologic and petrographic diagnostic properties, including the chemical composition of clay and minerals found in the clay. In the presented work the experimental sets up, sample preparation procedure and measurements programme will be discussed in details. Finally, the elemental and mineral compositions will be presented for studied different groups of the samples. - Highlights: • XRF analysis and X-ray diffraction used in studies of the till samples. • The till samples were collected from different regions of Holy Cross Mountains. • The analysis concentrates both on the samples from surface and from core borehole. • The purpose is determination of the local lithotype of the tills. • The experimental setup, sample preparation, measurements and results are discussed

Till Moritz Karbach (1979 - 2015)

CERN Document Server

2015-01-01

Till Moritz Karbach, a 35-year-old physicist on the LHCb experiment, suffered a fatal fall on 9 April while rock climbing near the city of Pegnitz in southern Germany. Despite the immediate attention of his companions and the rapid arrival of medical help, he passed away at the scene of the accident.   Moritz joined the LHCb collaboration in the summer of 2009, having written his PhD thesis on data collected at the BaBar experiment at SLAC, California. At this time he was a postdoc in the Dortmund group, where he had also been a student. Two years later he relocated to Geneva, and in July 2012 began a CERN research fellowship. Moritz’s contributions to LHCb were wide-ranging. He was a very active analyst, with particular interest in the measurement of the CP-violating phase γ, a topic that he had originally studied during his time on BaBar. He was a key player in several γ–related measurements, and the leading authority within the experiment on how th...

African Journal of Biotechnology - Vol 9, No 21 (2010)

African Journals Online (AJOL)

African Journal of Biotechnology. ... Genotype x Environment interaction for quality traits in durum wheat cultivars adapted to different ... Effects of genetically modified herbicide-tolerant (GMHT) rice on biodiversity of weed in paddy fields ...

Geostatistical description of geological heterogeneity in clayey till as input for improved characterization of contaminated sites

DEFF Research Database (Denmark)

Kessler, Timo Christian; Klint, K.E.S.; Renard, P.

2010-01-01

In low-permeability clay tills subsurface transport is governed by preferential flow in sand lenses and fractures. A proper geological model requires the integration of these features, i.e. the spatial distribution of the geological heterogeneities. Detailed mapping of sand lenses has been done...... at a clay till outcrop in Denmark to characterise the shapes and the spatial variability. Further, geostatistics were applied to simulate the distribution and to develop a heterogeneity model that can be incorporated into an existing geological model of, for example, a contaminated site....

Preferential flow and pesticide transport in a clay-rich till: Field, laboratory, and modeling analysis

Science.gov (United States)

JøRgensen, Peter R.; Hoffmann, Martin; Kistrup, Jens P.; Bryde, Claus; Bossi, Rossana; Villholth, Karen G.

2002-11-01

This study investigates vertical flow and pesticide transport along fractures in water saturated unoxidized clayey till. From two experimental fields, each 40 m2, 96% and 98%, respectively, of total vertical flow was conducted along fractures in the till, while the remaining 2-4% of flow occurred in the clay matrix at very slow flow rate. An applied dye tracer was observed only along 10-26% of the total fracture length measured on the horizontal surface of the experimental fields. In vertical sections the dyed fracture portions constituted root channels, which penetrated the till vertically along the fractures into the local aquifer at 5 m depth. No dye tracer was observed in the fractures without root channels or in the unfractured clay matrix, suggesting that root growth along the fracture surfaces was the principal agent of fracture aperture enhancement. Using hydraulic fracture aperture values determined from large undisturbed column (LUC) collected from one of the experimental fields, it was estimated that 94% of flow in the fractures was conducted along the fracture root channels, while only 6% of flow was conducted along the fracture sections without root channels. For natural vertical hydraulic gradients (0.8-2.3 at the site), flow rates of 0.8-2 km/d were determined for a fracture root channel, while fracture sections without root channels revealed flow rates of 9-22 m/d. Corresponding flow rates in the unfractured matrix were 7-19 mm/yr. For infiltrated bromide (nonreactive tracer) and mobile pesticides mecoprop (MCPP) and metsulfuron, very rapid migration (0.28-0.5 m/d) and high relative breakthrough concentrations (30-60%) into the aquifer were observed to occur along the fracture root channels using a constant hydraulic gradient of 1. Only traces were measured from infiltration of the strongly sorbed pesticide prochloraz. The concentrations of the bromide and pesticides in the monitoring wells were modeled with a discrete fracture matrix diffusion

The stability of soil aggregates in tilled fallow areas in Hyderabad district, Pakistan

Directory of Open Access Journals (Sweden)

Tagar Ahmed

2015-12-01

Full Text Available Arid areas are particularly susceptible to soil erosion due to long dry periods and sudden heavy downpours. This study investigates the aggregate size distribution and aggregate stability of twelve tilled fallow areas of Hyderabad district, Sindh, Pakistan. This study determined aggregate size distribution by dry sieving to evaluate the seedbed condition and aggregate stability using wet sieving to assess the susceptibility of tilled fallow areas to soil erosion. The aggregate size distribution of the soils of the selected areas was highly variable. Gulistan-e-Sarmast had the largest number of clods (51.0% followed by Kohsar (49.0%, Latifabad # 10 (41.10% and Daman-e-Kohsar (39.0%. Fazal Sun City, the left side of the Indus River, the Village Nooral Detha and the left side of the Abdullah Sports city had a greater number of large (>8.0 mm and small aggregates (<0.5 mm. The optimum aggregate size distribution was found in the left side of the channel, which had the largest number of aggregates (50.50% in the 0.5–8.0 mm sieve size range. Maximum aggregate stability (AS was found in Gulistan-e-Sarmast (46%, Kohsar (42% and Latifabad # 10 (34%, while all other soils had minimum aggregate stability (<14%. The minimum aggregate stabilities demonstrate that the tilled fallow areas of Hyderabad district are highly susceptible to erosion. Therefore, the present study suggests investigating potential ways to enhance the aggregate stabilities of soils.

Investigations of effective porosity of till by means of a combined soil-moisture/density gauge

International Nuclear Information System (INIS)

Nordberg, L.; Modig, S.

1974-01-01

Effective porosity and processes of saturation and dewatering in till have been investigated. The study was performed in undisturbed till columns, surrounded by ring-shaped excavations filled with sand. The procedure allowed for a raising and lowering of an artificial groundwater level in the till under controlled conditions, which in turn made possible controlled processes of saturation and dewatering. A combined gamma-neutron soil moisture /density gauge was used. The water content was recorded during a period in which water was added to a specially prepared, undisturbed in-situ soil column until a state of saturation was reached. This was followed by a period of induced dewatering by gravity drainage. The drainage was recorded until a steady state> approximately equalling field capacity, was approached (5-16 d). Water contents at saturation are assumed approximately to equal total porosity, having a range of 17.9-32.0% in the investigated till. The intensity of drainage was highest on the first day of dewatering and then diminished with time. A perfectly steady state was never reached. Therefore field capacity is used with indices, indicating the length of time of drainage. Consequently, effective porosity is qualified by the corresponding indices. After 15-16 days of gravity drainage, effective porosity was calculated to be on the average 7.4% at one test plot and 3.4% at another. The difference has been attributed to a corresponding difference in depth to the natural groundwater level; because of the method used a higher groundwater level and capillary fringe may have hampered the complete drainage, resulting in a relatively low value of effective porosity. The investigation is most likely to be applicable in water balance studies, groundwater discharge predictions and various construction and waste-water projects in moraine terrain. (author)

Matthew and marginality

Directory of Open Access Journals (Sweden)

Denis C. Duling

1995-12-01

Full Text Available This article explores marginality theory as it was first proposed in  the social sciences, that is related to persons caught between two competing cultures (Park; Stonequist, and, then, as it was developed in sociology as related to the poor (Germani and in anthropology as it was related to involuntary marginality and voluntary marginality (Victor Turner. It then examines a (normative scheme' in antiquity that creates involuntary marginality at the macrosocial level, namely, Lenski's social stratification model in an agrarian society, and indicates how Matthean language might fit with a sample inventory  of socioreligious roles. Next, it examines some (normative schemes' in  antiquity for voluntary margi-nality at the microsocial level, namely, groups, and examines how the Matthean gospel would fit based on indications of factions and leaders. The article ,shows that the author of the Gospel of Matthew has an ideology of (voluntary marginality', but his gospel includes some hope for (involuntary  marginals' in  the  real world, though it is somewhat tempered. It also suggests that the writer of the Gospel is a (marginal man', especially in the sense defined by the early theorists (Park; Stone-quist.

A rich TILLING resource for studying gene function in Brassica rapa

Directory of Open Access Journals (Sweden)

Amoah Stephen

2010-04-01

Full Text Available Abstract Background The Brassicaceae family includes the model plant Arabidopsis thaliana as well as a number of agronomically important species such as oilseed crops (in particular Brassica napus, B. juncea and B. rapa and vegetables (eg. B. rapa and B. oleracea. Separated by only 10-20 million years, Brassica species and Arabidopsis thaliana are closely related, and it is expected that knowledge obtained relating to Arabidopsis growth and development can be translated into Brassicas for crop improvement. Moreover, certain aspects of plant development are sufficiently different between Brassica and Arabidopsis to warrant studies to be carried out directly in the crop species. However, mutating individual genes in the amphidiploid Brassicas such as B. napus and B. juncea may, on the other hand, not give rise to expected phenotypes as the genomes of these species can contain up to six orthologues per single-copy Arabidopsis gene. In order to elucidate and possibly exploit the function of redundant genes for oilseed rape crop improvement, it may therefore be more efficient to study the effects in one of the diploid Brassica species such as B. rapa. Moreover, the ongoing sequencing of the B. rapa genome makes this species a highly attractive model for Brassica research and genetic resource development. Results Seeds from the diploid Brassica A genome species, B. rapa were treated with ethyl methane sulfonate (EMS to produce a TILLING (Targeting Induced Local Lesions In Genomes population for reverse genetics studies. We used the B. rapa genotype, R-o-18, which has a similar developmental ontogeny to an oilseed rape crop. Hence this resource is expected to be well suited for studying traits with relevance to yield and quality of oilseed rape. DNA was isolated from a total of 9,216 M2 plants and pooled to form the basis of the TILLING platform. Analysis of six genes revealed a high level of mutations with a density of about one per 60 kb. This

Cover Crop-Based, Organic Rotational No-Till Corn and Soybean Production Systems in the Mid-Atlantic United States

Directory of Open Access Journals (Sweden)

John M. Wallace

2017-04-01

Full Text Available Cover crop-based, organic rotational no-till (CCORNT corn and soybean production is becoming a viable strategy for reducing tillage in organic annual grain systems in the mid-Atlantic, United States. This strategy relies on mechanical termination of cover crops with a roller-crimper and no-till planting corn and soybean into cover crop mulches. Here, we report on recent research that focuses on integrated approaches for crop, nutrient and pest management in CCORNT systems that consider system and regional constraints for adoption in the mid-Atlantic. Our research suggests that no-till planting soybean into roller-crimped cereal rye can produce consistent yields. However, constraints to fertility management have produced less consistent no-till corn yields. Our research shows that grass-legume mixtures can improve N-release synchrony with corn demand and also improve weed suppression. Integration of high-residue inter-row cultivation improves weed control consistency and may reduce reliance on optimizing cover crop biomass accumulation for weed suppression. System-specific strategies are needed to address volunteer cover crops in later rotational phases, which result from incomplete cover crop termination with the roller crimper. The paucity of adequate machinery for optimizing establishment of cash crops into thick residue mulch remains a major constraint on CCORNT adoption. Similarly, breeding efforts are needed to improve cover crop germplasm and develop regionally-adapted varieties.

Feasibility and Performance of Full-Scale In-situ Remediation of TCE by ERD in Clay Tills

DEFF Research Database (Denmark)

Broholm, Mette Martina; Damgaard, Ida; Chambon, Julie Claire Claudia

The feasibility and performance of full-scale applications of ERD in clay tills were investigated in a research project including 2 sites in Denmark, which have been undergoing remediation since 2006. At both sites organic substrates and bioaugmentation cultures have been injected in TCE-contamin......The feasibility and performance of full-scale applications of ERD in clay tills were investigated in a research project including 2 sites in Denmark, which have been undergoing remediation since 2006. At both sites organic substrates and bioaugmentation cultures have been injected in TCE...... been applied. The results showed that the chlorinated solvent TCE was converted into its daughter products (cDCE, VC and ethene) but complete conversion of contaminants to ethene (as expected) was not achieved within a timeframe of 4 years. Large variation in the effect of ERD in the clay matrix...... features in some parts of the clay tills. The bioactive zones may expand in zones where both donor and chlorinated compounds are present. In some cores TCE was depleted (degraded to DCE) in zones up to 1.8 m thick – an extent which could not be explained by diffusive loss to narrow bioactive zones. Hence...

First TILLING platform in Cucurbita pepo: a new mutant resource for gene function and crop improvement.

Science.gov (United States)

Vicente-Dólera, Nelly; Troadec, Christelle; Moya, Manuel; del Río-Celestino, Mercedes; Pomares-Viciana, Teresa; Bendahmane, Abdelhafid; Picó, Belén; Román, Belén; Gómez, Pedro

2014-01-01

Although the availability of genetic and genomic resources for Cucurbita pepo has increased significantly, functional genomic resources are still limited for this crop. In this direction, we have developed a high throughput reverse genetic tool: the first TILLING (Targeting Induced Local Lesions IN Genomes) resource for this species. Additionally, we have used this resource to demonstrate that the previous EMS mutant population we developed has the highest mutation density compared with other cucurbits mutant populations. The overall mutation density in this first C. pepo TILLING platform was estimated to be 1/133 Kb by screening five additional genes. In total, 58 mutations confirmed by sequencing were identified in the five targeted genes, thirteen of which were predicted to have an impact on the function of the protein. The genotype/phenotype correlation was studied in a peroxidase gene, revealing that the phenotype of seedling homozygous for one of the isolated mutant alleles was albino. These results indicate that the TILLING approach in this species was successful at providing new mutations and can address the major challenge of linking sequence information to biological function and also the identification of novel variation for crop breeding.

A mutant Brassica napus (canola population for the identification of new genetic diversity via TILLING and next generation sequencing.

Directory of Open Access Journals (Sweden)

Erin J Gilchrist

Full Text Available We have generated a Brassica napus (canola population of 3,158 EMS-mutagenised lines and used TILLING to demonstrate that the population has a high enough mutation density that it will be useful for identification of mutations in genes of interest in this important crop species. TILLING is a reverse genetics technique that has been successfully used in many plant and animal species. Classical TILLING involves the generation of a mutagenised population, followed by screening of DNA samples using a mismatch-specific endonuclease that cleaves only those PCR products that carry a mutation. Polyacrylamide gel detection is then used to visualise the mutations in any gene of interest. We have used this TILLING technique to identify 432 unique mutations in 26 different genes in B. napus (canola cv. DH12075. This reflects a mutation density ranging from 1/56 kb to 1/308 kb (depending on the locus with an average of 1/109 kb. We have also successfully verified the utility of next generation sequencing technology as a powerful approach for the identification of rare mutations in a population of plants, even in polyploid species such as B. napus. Most of the mutants we have identified are publically available.

The Current State and Future Directions of Organic No-Till Farming with Cover Crops in Canada, with Case Study Support

Directory of Open Access Journals (Sweden)

Heather M. Beach

2018-01-01

Full Text Available Eliminating regular tillage practices in agriculture has numerous ecological benefits that correspond to the intentions of organic agriculture; yet, more tillage is conducted in organic agriculture than in conventional agriculture. Organic systems face more management challenges to avoid tillage. This paper identifies factors to consider when implementing no-till practices particularly in organic agronomic and vegetable crop agriculture and describes techniques to address these factors. In some cases, future research is recommended to effectively address the current limitations. The format includes a literature review of organic no-till (OrgNT research and two case studies of Ontario organic farmers that highlight no-till challenges and practices to overcome these challenges. Cover crops require significant consideration because they are the alternative to herbicides and fertilizers to manage weeds and provide nutrients in the OrgNT system. Equipment requirements have also proven to be unique in OrgNT systems. In the future, it is recommended that researchers involve organic farmers closely in studies on no-till implementation, so that the farmers’ concerns are effectively addressed, and research is guided by possibilities recognized by the practitioners.

Hydrogeological Characterization of Low-permeability Clayey Tills

DEFF Research Database (Denmark)

Kessler, Timo Christian

The topic of this PhD thesis is an integrated investigation of sand lenses in glacial diamictons. Sand lenses indicate various deposition regimes and glaciotectonic deformation styles and are as such important features in studies of glacial sediments. In a hydrogeological framework, sand lenses......-dimensional realizations indicate clear channel networks, whereas only limited connectivity was found for the two-dimensional case. This is an important aspect because it emphasizes the need to collect data and to represent this type of heterogeneity in 3D. The physical response of sand lens heterogeneity was evaluated...... enhance the horizontal spreading of contaminants without a significant increase of the equivalent permeability in the till. Overall, sand lenses occur in all types of glacial sediments and with a broad range of shapes and hydraulic properties. Geometric characterization enabled classification of the most...

Marginal and happy? The need for uniqueness predicts the adjustment of marginal immigrants.

Science.gov (United States)

Debrosse, Régine; de la Sablonnière, Roxane; Rossignac-Milon, Maya

2015-12-01

Marginalization is often presented as the strategy associated with the worst adjustment for immigrants. This study identifies a critical variable that buffers marginal immigrants from the negative effects of marginalization on adjustment: The need for uniqueness. In three studies, we surveyed immigrants recruited on university campuses (n = 119, n = 116) and in the field (n = 61). Among marginal immigrants, a higher need for uniqueness predicted higher self-esteem (Study 1), affect (Study 2), and life satisfaction (Study 3), and marginally higher happiness (Study 2) and self-esteem (Study 3). No relationship between the need for uniqueness and adjustment was found among non-marginal immigrants. The adaptive value of the need for uniqueness for marginal immigrants is discussed. © 2015 The British Psychological Society.

Hur äldres sexualitet och sexuella hälsa är kopplade till deras livskvalitet : En litteraturstudie

OpenAIRE

Heinrich, Elsa; Johansson, Amanda

2016-01-01

Sexualiteten och den sexuella hälsan är en grundpelare i att varje människas individualitet. Det finns ett fördomsfullt synsätt angående äldre och deras sexualitet där gruppen blir betraktade som asexuell. Ämnet är tabubelagt och det föreligger relativt lite kunskap kring det. Livskvalitet är en subjektiv upplevelse som förändras över tid. Åldrandet bidrar till flera riskfaktorer som kan leda till nedsatt livskvalitet. Denna litteraturstudies syfte var att undersöka hur sexualitet och sexuell...

Alteration of podzolized tills by acid load near Ni-Cu smelters at Monchegorsk, Kola Peninsula, Russia

Directory of Open Access Journals (Sweden)

Räisänen, M.L.

1994-06-01

Full Text Available Mineralogy and geochemistry of podzolized tills was studied in the area of dieback forest near the Ni-Cu smelters at Monchegorsk, and less extensively forest damage near by Apatity and Kirovsk in the Russian Kola Peninsula. The abundances of main elements (Si, Al, Fe, Mg, Ca, K, Na in the <64 μm fraction were determined by the hot aqua regia digestion method and inductively coupled plasma spectrometry. The clay mineralogy of the silt plus clay fraction was examined by X-ray diffraction after selective extraction and heating treatments. At all study sites, trioctahedral mica and chlorite were totally weathered from the silt and clay fraction (<64 μm of the eluvial layer, leaving behind interstratified mica-vermiculite-smectite clays. In general, the mixed-layer clay of the eluvial layer had low levels of hydroxy interlayering. Illuviated layers were characterized by hydroxy interlayered vermiculite-chlorite. The abundance of chlorite and mica was greater, and the degree of interlayering lower, in parent tills than in the overlying illuviated layers. Regardless of differences in bedrock and till geochemistry, the weathering sequence throughout the podzolized till profile was coherent at most of the sampling sites. Exceptionally, in a few profiles sampled at the totally destroyed forest site, the swelling mixed-layer clay of the eluvial layer displayed a neochloritized structure. On the basis of XRD patterns and geochemistry of the samples, it was inferred that a short-term decomposition of plagioclase had promoted, via inputs of Al-hydroxides, the transformation of mica-vermiculite-smectite to a poorly crystalline interstratification of chlorite-aluminous montmorillonite. The accelerated weathering occurring occasionally in exposed places was probably activated by the strongly acidic load in the vicinity of the smelters and the city of Monchegorsk.

Stratification of soil chemical and microbial properties under no-till management after lime amendment

Science.gov (United States)

Adoption of no-till (NT) technology in the dryland cropping region of the inland Pacific Northwest (iPNW) has dramatically reduced soil erosion compared to conventional tillage. Soils under continuous NT, however, often produce stratified soil acidification compared with conventional tillage due to ...

Combining ground-based and airborne EM through Artificial Neural Networks for modelling glacial till under saline groundwater conditions

DEFF Research Database (Denmark)

Gunnink, J.L.; Bosch, A.; Siemon, B.

2012-01-01

Airborne electromagnetic (AEM) methods supply data over large areas in a cost-effective way. We used ArtificialNeural Networks (ANN) to classify the geophysical signal into a meaningful geological parameter. By using examples of known relations between ground-based geophysical data (in this case...... electrical conductivity, EC, from electrical cone penetration tests) and geological parameters (presence of glacial till), we extracted learning rules that could be applied to map the presence of a glacial till using the EC profiles from the airborne EM data. The saline groundwater in the area was obscuring...

Lithologic influences on groundwater recharge through incised glacial till from profile to regional scales: Evidence from glaciated Eastern Nebraska

Science.gov (United States)

Gates, John B.; Steele, Gregory V.; Nasta, Paolo; Szilagyi, Jozsef

2014-01-01

Variability in sediment hydraulic properties associated with landscape depositional and erosional features can influence groundwater recharge processes by affecting soil-water storage and transmission. This study considers recharge to aquifers underlying river-incised glaciated terrain where the distribution of clay-rich till is largely intact in upland locations but has been removed by alluvial erosion in stream valleys. In a stream-dissected glacial region in eastern Nebraska (Great Plains region of the United States), recharge estimates were developed for nested profile, aquifer, and regional scales using unsaturated zone profile measurements (matric potentials, Cl- and 3H), groundwater tracers (CFC-12 and SF6), and a remote sensing-assisted water balance model. Results show a consistent influence of till lithology on recharge rates across nested spatial scales despite substantial uncertainty in all recharge estimation methods, suggesting that minimal diffuse recharge occurs through upland glacial till lithology whereas diffuse recharge occurs in river valleys where till is locally absent. Diffuse recharge is estimated to account for a maximum of 61% of total recharge based on comparison of diffuse recharge estimated from the unsaturated zone (0-43 mm yr-1) and total recharge estimated from groundwater tracers (median 58 mm yr-1) and water balance modeling (median 56 mm yr-1). The results underscore the importance of lithologic controls on the distributions of both recharge rates and mechanisms.

Use of no-till winter wheat by nesting ducks in North Dakota

Science.gov (United States)

Duebbert, H.F.; Kantrud, H.A.

1987-01-01

Nesting of dabbling ducks (Anatinae) was studied in fields of no-till winter wheat (Triticum aestivum) in the prairie pothole region of North Dakota during 1984 and 1985. Total area of 59 fields searched in 1984 was 1,135 ha and total area of 70 fields searched in 1985 was 1,175 ha. Field sizes ranged from 3 ha to 110 ha. Nests of five duck species were found: blue-winged teal (Anas discors), 55 nests; northern pintail (A. acuta), 44; mallard (A. platyrhynchos), 29; gadwall (A. strepera), 15; and northern shoveler (A. clypeata), 8. The average number of nests found was 8/100 ha in 1984 and 6/100 ha in 1985. Nest success for all species averaged 26% in 1984 and 29% in 1985. Predation by mammals was the principal cause of nest destruction. No egg or hen mortality could be attributed to pesticide use. Only 6 of 151 nests (4%) were abandoned during the two years. We also found 29 nests of seven other ground-nesting bird species. The trend toward increased planting of no-till winter wheat in the prairie pothole region should benefit production of ducks and other ground-nesting birds.

Kan ekologisk och ekonomisk hållbarhet kombineras? : En studie av en neoklassisk jämviktsmodell och dess relation till hållbarhet

OpenAIRE

Pettersson, David

2015-01-01

Bakgrunden till examensarbetet är att aktiviteter kopplat till den globala ekonomin samt tillväxt av denna har skapat en situation som i dagsläget inte uppfyller den ekologiska dimensionen av hållbarhet. Lösningar för att minska den miljöpåverkan som sker idag samtidigt som ekonomisk tillväxt sker har kritiserats och istället föreslås ekonomier med låg eller ingen tillväxt. Med bakgrund till detta har forskningsprojektet Bortom BNP-tillväxt startat och examensarbetet genomförs hos ekonomiska ...

The Passive Microwave Remote Sensing of Soil Moisture: the Effect of Tilled Row Structure

Science.gov (United States)

Wang, J. R.; Newton, R. W.; Rouse, J. W.

1979-01-01

The tilled rowstructure is known to be one of the important factors affecting the observations of the microwave emission from a natural surface. Measurements of this effect were carried out with both I and X band radiometers mounted on a mobile truck on a bare 40 m x 45 m row tilled field. The soil moisture content during the measurements ranged from approximately 10 percent to approximately 30 percent by dry weight. The results of these measurements showed that the variations of the antenna temperatures with incident angle theta changed with the azimuthal angle a measured from the row direction. A numerical calculation based on a composite surface roughness was made and found to predict the observed features within the model's limit of accuracy. It was concluded that the difference between the horizontally and vertically polarized temperatures was due to the change in the local angle of field emission within the antenna field of view caused by the large scale row structure.

In Winter Wheat, No-Till Increases Mycorrhizal Colonization thus Reducing the Need for Nitrogen Fertilization

Directory of Open Access Journals (Sweden)

Julien Verzeaux

2016-06-01

Full Text Available Arbuscular mycorrhizal fungi (AMF play a major role in the uptake of nutrients by agricultural plants. Nevertheless, some agricultural practices can interrupt fungal-plant signaling and thus impede the establishment of the mycorrhizal symbiosis. A field experiment performed over a 5-year period demonstrated that both the absence of tillage and of nitrogen (N fertilization improved AMF colonization of wheat roots. Moreover, under no-till conditions, N uptake and aboveground biomass production did not vary significantly between N-fertilized and N-unfertilized plots. In contrast, both N uptake and above ground biomass were much lower when N fertilizer was not added during conventional tillage. This finding strongly suggests that for wheat, no-till farming is a sustainable agricultural system that allows a gradual reduction in N fertilizer use by promoting AMF functionality and at the same time increasing N uptake.

Field scale heterogeneity of redox conditions in till-upscaling to a catchment nitrate model

DEFF Research Database (Denmark)

Hansen, J.R.; Erntsen, V.; Refsgaard, J.C.

2008-01-01

Point scale studies in different settings of glacial geology show a large local variation of redox conditions. There is a need to develop an upscaling methodology for catchment scale models. This paper describes a study of field-scale heterogeneity of redox-interfaces in a till aquitard within an...

"We call ourselves marginalized"

DEFF Research Database (Denmark)

Jørgensen, Nanna Jordt

2014-01-01

of the people we refer to as marginalized. In this paper, I discuss how young secondary school graduates from a pastoralist community in Kenya use and negotiate indigeneity, marginal identity, and experiences of marginalization in social navigations aimed at broadening their current and future opportunities. I...

Webbaserad pedagogisk meritportfölj - från idé till verklighet

Directory of Open Access Journals (Sweden)

Jakob Johansson

2011-03-01

Full Text Available Pedagogisk meritering och pedagogiska meritportföljer har under det senaste decenniet fått ökad uppmärksamhet. Idag (mars 2011 ger en sökning på Google® 6 140 respektive 1 990 träffar på dessa två sökord. Många av träffarna på Google® handlar om högskolors rekommendationer att dokumentera pedagogiska meriter, men antalet publicerade artiklar i detta ämne är mycket få. Högskolan behöver bra lärare och för att uppnå det så måste undervisning och andra utbildningsinsatser uppmärksammas och belönas. Användandet av pedagogiska meritportföljer anses öka betydelsen av undervisningsinsatsen vid anställningar och befordran och är ett sätt att professionalisera undervisning (Fayne, 1991. Många högskolor och universitet har utarbetat handlingsplaner för hur pedagogiska meriter ska dokumenteras och bedömas liksom strategier för hur medarbetarna ska utveckla sin pedagogiska skicklighet. ”Uppifrån” finns således både skrivna dokument och viljan och intentionen att premiera pedagogiska insatser. Trots detta upplever många medarbetare att pedagogiska insatser inte lönar sig att dokumentera då dessa meriter inte värderas tillräckligt högt, exempelvis i jämförelse med forskningsmeriter. Samtidigt vittnar pedagogiskt sakkunniga om att de pedagogiska meritportföljer som de ombeds granska (vid exempelvis tjänstetillsättningar ofta är ostrukturerade och av varierande kvalité. För att pedagogiska meriter ska få avsedd tyngd vid tjänstetillsättningar fordras att de redovisas på ett sätt som gör det möjligt för sakkunniga att värdera dem. Bedömning av både vetenskapliga och pedagogiska meriter görs i många fall av sakkunniga utan särskild pedagogisk utbildning och de pedagogiska meriterna anses generellt mer svårbedömda än de vetenskapliga (Lindberg, 1997. Någon form av standardisering och mallar i samband med presentation av pedagogiska meriter bör därför kunna vara till hjälp för s

Marginal Matter

Science.gov (United States)

van Hecke, Martin

2013-03-01

All around us, things are falling apart. The foam on our cappuccinos appears solid, but gentle stirring irreversibly changes its shape. Skin, a biological fiber network, is firm when you pinch it, but soft under light touch. Sand mimics a solid when we walk on the beach but a liquid when we pour it out of our shoes. Crucially, a marginal point separates the rigid or jammed state from the mechanical vacuum (freely flowing) state - at their marginal points, soft materials are neither solid nor liquid. Here I will show how the marginal point gives birth to a third sector of soft matter physics: intrinsically nonlinear mechanics. I will illustrate this with shock waves in weakly compressed granular media, the nonlinear rheology of foams, and the nonlinear mechanics of weakly connected elastic networks.

Long-term no-till: A major driver of fungal communities in dryland wheat cropping systems.

Directory of Open Access Journals (Sweden)

Dipak Sharma-Poudyal

Full Text Available In the dryland Pacific Northwest wheat cropping systems, no-till is becoming more prevalent as a way to reduce soil erosion and fuel inputs. Tillage can have a profound effect on microbial communities and soilborne fungal pathogens, such as Rhizoctonia. We compared the fungal communities in long-term no-till (NT plots adjacent to conventionally tilled (CT plots, over three years at two locations in Washington state and one location in Idaho, US. We used pyrosequencing of the fungal ITS gene and identified 422 OTUs after rarefication. Fungal richness was higher in NT compared to CT, in two of the locations. Humicola nigrescens, Cryptococcus terreus, Cadophora spp. Hydnodontaceae spp., and Exophiala spp. were more abundant in NT, while species of Glarea, Coniochaetales, Mycosphaerella tassiana, Cryptococcus bhutanensis, Chaetomium perlucidum, and Ulocladium chartarum were more abundant in CT in most locations. Other abundant groups that did not show any trends were Fusarium, Mortierella, Penicillium, Aspergillus, and Macroventuria. Plant pathogens such as Rhizoctonia (Ceratobasidiaceae were not abundant enough to see tillage differences, but Microdochium bolleyi, a weak root pathogen, was more abundant in NT. Our results suggest that NT fungi are better adapted at utilizing intact, decaying roots as a food source and may exist as root endophytes. CT fungi can utilize mature plant residues that are turned into the soil with tillage as pioneer colonizers, and then produce large numbers of conidia. But a larger proportion of the fungal community is not affected by tillage and may be niche generalists.

Modelling tools for assessing bioremediation performance and risk of chlorinated solvents in clay tills

DEFF Research Database (Denmark)

Chambon, Julie Claire Claudia

design are challenging. This thesis presents the development and application of analytical and numerical models to improve our understanding of transport and degradation processes in clay tills, which is crucial for assessing bioremediation performance and risk to groundwater. A set of modelling tools...... to groundwater and bioremediation performance in low-permeability media....

Marginalization of the Youth

DEFF Research Database (Denmark)

Jensen, Niels Rosendal

2009-01-01

The article is based on a key note speach in Bielefeld on the subject "welfare state and marginalized youth", focusing upon the high ambition of expanding schooling in Denmark from 9 to 12 years. The unintended effect may be a new kind of marginalization.......The article is based on a key note speach in Bielefeld on the subject "welfare state and marginalized youth", focusing upon the high ambition of expanding schooling in Denmark from 9 to 12 years. The unintended effect may be a new kind of marginalization....

Convexity and Marginal Vectors

NARCIS (Netherlands)

van Velzen, S.; Hamers, H.J.M.; Norde, H.W.

2002-01-01

In this paper we construct sets of marginal vectors of a TU game with the property that if the marginal vectors from these sets are core elements, then the game is convex.This approach leads to new upperbounds on the number of marginal vectors needed to characterize convexity.An other result is that

Contributions to knowledge of the continental margin of Uruguay. Uruguayan continental margin: Physiographic and seismic analysis

International Nuclear Information System (INIS)

Preciozzi, F

2014-01-01

This work is about the kind of continental margins such as a )Atlantic type passive margins which can be hard or soft b) An active or Pacific margins that because of the very frequent earthquakes develop a morphology dominated by tectonic processes. The Uruguayan continental margin belongs to a soft Atlantic margin

Fixing soft margins

NARCIS (Netherlands)

P. Kofman (Paul); A. Vaal, de (Albert); C.G. de Vries (Casper)

1993-01-01

textabstractNon-parametric tolerance limits are employed to calculate soft margins such as advocated in Williamson's target zone proposal. In particular, the tradeoff between softness and zone width is quantified. This may be helpful in choosing appropriate margins. Furthermore, it offers

SOCIAL MARGINALIZATION AND HEALTH

Directory of Open Access Journals (Sweden)

Marjana Bogdanović

2007-04-01

Full Text Available The 20th century was characterized by special improvement in health. The aim of WHO’s policy EQUITY IN HEALTH is to enable equal accessibility and equal high quality of health care for all citizens. More or less some social groups have stayed out of many social systems even out of health care system in the condition of social marginalization. Phenomenon of social marginalization is characterized by dynamics. Marginalized persons have lack of control over their life and available resources. Social marginalization stands for a stroke on health and makes the health status worse. Low socio-economic level dramatically influences people’s health status, therefore, poverty and illness work together. Characteristic marginalized groups are: Roma people, people with AIDS, prisoners, persons with development disorders, persons with mental health disorders, refugees, homosexual people, delinquents, prostitutes, drug consumers, homeless…There is a mutual responsibility of community and marginalized individuals in trying to resolve the problem. Health and other problems could be solved only by multisector approach to well-designed programs.

Pickering seismic safety margin

International Nuclear Information System (INIS)

Ghobarah, A.; Heidebrecht, A.C.; Tso, W.K.

1992-06-01

A study was conducted to recommend a methodology for the seismic safety margin review of existing Canadian CANDU nuclear generating stations such as Pickering A. The purpose of the seismic safety margin review is to determine whether the nuclear plant has sufficient seismic safety margin over its design basis to assure plant safety. In this review process, it is possible to identify the weak links which might limit the seismic performance of critical structures, systems and components. The proposed methodology is a modification the EPRI (Electric Power Research Institute) approach. The methodology includes: the characterization of the site margin earthquake, the definition of the performance criteria for the elements of a success path, and the determination of the seismic withstand capacity. It is proposed that the margin earthquake be established on the basis of using historical records and the regional seismo-tectonic and site specific evaluations. The ability of the components and systems to withstand the margin earthquake is determined by database comparisons, inspection, analysis or testing. An implementation plan for the application of the methodology to the Pickering A NGS is prepared

Indian Ocean margins

Digital Repository Service at National Institute of Oceanography (India)

Naqvi, S.W.A

in the latter two areas. Some of these fluxes are expected to be substantial in the case of Indonesian continental margins and probably also across the eastern coasts of Africa not covered in this chapter. However, a dearth of information makes these margins...

Marginal kidney donor

Directory of Open Access Journals (Sweden)

Ganesh Gopalakrishnan

2007-01-01

Full Text Available Renal transplantation is the treatment of choice for a medically eligible patient with end stage renal disease. The number of renal transplants has increased rapidly over the last two decades. However, the demand for organs has increased even more. This disparity between the availability of organs and waitlisted patients for transplants has forced many transplant centers across the world to use marginal kidneys and donors. We performed a Medline search to establish the current status of marginal kidney donors in the world. Transplant programs using marginal deceased renal grafts is well established. The focus is now on efforts to improve their results. Utilization of non-heart-beating donors is still in a plateau phase and comprises a minor percentage of deceased donations. The main concern is primary non-function of the renal graft apart from legal and ethical issues. Transplants with living donors outnumbered cadaveric transplants at many centers in the last decade. There has been an increased use of marginal living kidney donors with some acceptable medical risks. Our primary concern is the safety of the living donor. There is not enough scientific data available to quantify the risks involved for such donation. The definition of marginal living donor is still not clear and there are no uniform recommendations. The decision must be tailored to each donor who in turn should be actively involved at all levels of the decision-making process. In the current circumstances, our responsibility is very crucial in making decisions for either accepting or rejecting a marginal living donor.

Long-term monitoring of nitrate transport to drainage from three agricultural clayey till fields

DEFF Research Database (Denmark)

Ernstsen, Vibeke; Olsen, Preben; Rosenbom, Annette E.

2015-01-01

-regulation in future. This study strives to provide such knowledge by evaluating on 11 years of nitrate-N con-centration measurements in drainage from three subsurface-drained clayey till fields (1.3–2.3 ha) representing approxi-mately 71 % of the surface sediments in Denmark dominated by clay. The fields differ...... in their inherent hydrogeological field settings (e.g. soil-type, geology, climate, drainage and groundwater table) and the agricultural management of the fields (e.g. crop type, type of N fertilisers and agricultural practices). The evaluation revealed three types of clayey till fields characterised by: (i) low net...... precipitation, high concen-tration of nitrate-N, and short-term low intensity drainage at air temperatures often below 5 ◦C; (ii) medium net precip-itation, medium concentration of nitrate-N, and short-term medium-intensity drainage at air temperatures often above 5 ◦C; and (iii) high net precipitation, low...

Statistical considerations for grain-size analyses of tills

Science.gov (United States)

Jacobs, A.M.

1971-01-01

Relative percentages of sand, silt, and clay from samples of the same till unit are not identical because of different lithologies in the source areas, sorting in transport, random variation, and experimental error. Random variation and experimental error can be isolated from the other two as follows. For each particle-size class of each till unit, a standard population is determined by using a normally distributed, representative group of data. New measurements are compared with the standard population and, if they compare satisfactorily, the experimental error is not significant and random variation is within the expected range for the population. The outcome of the comparison depends on numerical criteria derived from a graphical method rather than on a more commonly used one-way analysis of variance with two treatments. If the number of samples and the standard deviation of the standard population are substituted in a t-test equation, a family of hyperbolas is generated, each of which corresponds to a specific number of subsamples taken from each new sample. The axes of the graphs of the hyperbolas are the standard deviation of new measurements (horizontal axis) and the difference between the means of the new measurements and the standard population (vertical axis). The area between the two branches of each hyperbola corresponds to a satisfactory comparison between the new measurements and the standard population. Measurements from a new sample can be tested by plotting their standard deviation vs. difference in means on axes containing a hyperbola corresponding to the specific number of subsamples used. If the point lies between the branches of the hyperbola, the measurements are considered reliable. But if the point lies outside this region, the measurements are repeated. Because the critical segment of the hyperbola is approximately a straight line parallel to the horizontal axis, the test is simplified to a comparison between the means of the standard

Remediation of Stratified Soil Acidity Through Surface Application of Lime in No-Till Cropping Systems

Science.gov (United States)

Yield reduction and reduced crop vigor, resulting from soil acidification, are of increasing concern in eastern Washington and northern Idaho. In this region, soil pH has been decreasing at an accelerated rate, primarily due to the long-term use of ammonium based fertilizers. In no-till systems, the...

On marginal regeneration

NARCIS (Netherlands)

Stein, H.N.

1991-01-01

On applying the marginal regeneration concept to the drainage of free liquid films, problems are encountered: the films do not show a "neck" of minimum thickness at the film/border transition; and the causes of the direction dependence of the marginal regeneration are unclear. Both problems can be

Indigenous women's voices: marginalization and health.

Science.gov (United States)

Dodgson, Joan E; Struthers, Roxanne

2005-10-01

Marginalization may affect health care delivery. Ways in which indigenous women experienced marginalization were examined. Data from 57 indigenous women (18 to 65 years) were analyzed for themes. Three themes emerged: historical trauma as lived marginalization, biculturalism experienced as marginalization, and interacting within a complex health care system. Experienced marginalization reflected participants' unique perspective and were congruent with previous research. It is necessary for health care providers to assess the detrimental impact of marginalization on the health status of individuals and/or communities.

CHANGE OF CHOSEN SOIL PHYSICAL PROPERTIES OF CHERNOZEM AFTER SEVEN YEARS OF NO-TILL SOIL CULTIVATION

Directory of Open Access Journals (Sweden)

Katarna Hrckov

2014-09-01

Full Text Available Soil physical properties were investigated in two types of growing systems - integrated no-till system and conventional system with ploughing, in 1999 2005 on chernozem in maize growing region. Bulk density decreased and total porosity increased during 7 years in both growing systems. In integrated system the improvement of soil physical properties could be explained by remaining of plant residues on soil surface. In conventional system the plant residues were incorporated into soil by ploughing. This led to the higher proportion of organic matter in soil. Soil cultivated conventionally had significantly higher value of reduced bulk density, significantly lower porosity and significantly higher values of soil moisture compared to soil in integrated no-till system. Maximum capillary water capacity was not significantly influenced by soil cultivation. Values of investigated soil physical properties in both systems were not markedly different from the typical values of cultivated chernozem.

Refining margins and prospects

International Nuclear Information System (INIS)

Baudouin, C.; Favennec, J.P.

1997-01-01

Refining margins throughout the world have remained low in 1996. In Europe, in spite of an improvement, particularly during the last few weeks, they are still not high enough to finance new investments. Although the demand for petroleum products is increasing, experts are still sceptical about any rapid recovery due to prevailing overcapacity and to continuing capacity growth. After a historical review of margins and an analysis of margins by regions, we analyse refining over-capacities in Europe and the unbalances between production and demand. Then we discuss the current situation concerning barriers to the rationalization, agreements between oil companies, and the consequences on the future of refining capacities and margins. (author)

Safety margins in deterministic safety analysis

International Nuclear Information System (INIS)

Viktorov, A.

2011-01-01

The concept of safety margins has acquired certain prominence in the attempts to demonstrate quantitatively the level of the nuclear power plant safety by means of deterministic analysis, especially when considering impacts from plant ageing and discovery issues. A number of international or industry publications exist that discuss various applications and interpretations of safety margins. The objective of this presentation is to bring together and examine in some detail, from the regulatory point of view, the safety margins that relate to deterministic safety analysis. In this paper, definitions of various safety margins are presented and discussed along with the regulatory expectations for them. Interrelationships of analysis input and output parameters with corresponding limits are explored. It is shown that the overall safety margin is composed of several components each having different origins and potential uses; in particular, margins associated with analysis output parameters are contrasted with margins linked to the analysis input. While these are separate, it is possible to influence output margins through the analysis input, and analysis method. Preserving safety margins is tantamount to maintaining safety. At the same time, efficiency of operation requires optimization of safety margins taking into account various technical and regulatory considerations. For this, basic definitions and rules for safety margins must be first established. (author)

Marginal Models for Categorial Data

NARCIS (Netherlands)

Bergsma, W.P.; Rudas, T.

2002-01-01

Statistical models defined by imposing restrictions on marginal distributions of contingency tables have received considerable attention recently. This paper introduces a general definition of marginal log-linear parameters and describes conditions for a marginal log-linear parameter to be a smooth

Assessing Protection Afforded to the Microbiological Quality of Bedrock Groundwater from the Impacts of Septic Tank Effluent by Irish Glacial Till: A Field Study

Science.gov (United States)

Orr, Alison; McCarthy, Valerie; Meehan, Robert; Flynn, Raymond

2010-05-01

The rural population of Ireland relies almost exclusively on on-site treatment systems for disposal of waste water. Septic tank systems, which discharge effluent to ground, constitute the dominant means of waste water disposal. Many of the areas that employ this technology rely on private or small group groundwater supplies, often located in close proximity of septic tanks. Since many of these water supplies provide raw groundwater to consumers, septic tank effluent (STE) can pose a significant hazard to the microbiological quality of drinking water. T-tests (infiltration testing) carried out prior to tank installation aim to assess the capacity of subsoils to receive STE. Tests completed across Ireland indicate that many existing septic tank systems are located in low permeability subsoils. These subsoils are assumed to afford significant protection to the microbiological quality of groundwater in the underlying bedrock units. A two year investigation in the Lough Muckno Catchment in Co. Monaghan, investigating the impact of STE on water quality, involved carrying out T-tests at three sites where effluent discharged to a dense, silty, ‘fractured' glacial till derived from the underlying bedrock and containing clasts of low grade metamorphic Ordovician and Silurian sandstone and shale. Analysis of groundwater samples collected from 28 piezometers straddling the water table within the till, down-gradient of septic tank systems at two sites, permitted faecal indicator microorganism (FIO) levels in near-surface groundwater to be established. Associated hydraulic conductivity tests (slug tests) at all three sites permitted an evaluation of the levels of horizontal hydraulic conductivity heterogeneity present in the till. Slug test results suggest that till median hydraulic conductivities range from 1.1x10-4 cm/s to 1.1x10-5 cm/s, with variability of up to 2 orders of magnitude across each site. On the other hand no significant differences in properties existed

Simple model for daily evaporation from fallow tilled soil under spring conditions in a temperate climate.

NARCIS (Netherlands)

Boesten, J.J.T.I.; Stroosnijder, L.

1986-01-01

A simple parametric model is presented to estimate daily evaporation from fallow tilled soil under spring conditions in a temperate climate. In this model, cumulative actual evaporation during a drying cycle is directly proportional to the square root of cumulative potential evaporation. The model

Bildskapande i relation till genus i förskolans verksamhet : Att skapa sig själv och genus

OpenAIRE

Brännlund, Angelika

2018-01-01

Studiens syfte är att bidra till ökad medvetenhet för verksamma inom förskolans område kring frågor som rör pedagogers förhållningssätt kring relationen mellan bildskapande och genus, men även hur dessa förhållningssätt kan påverka barnens möjligheter i deras bildskapande. En viktig fråga som burits med från starten av arbetet och som lyser igenom i resultatdelen har varit: Vilka möjligheter att förhålla sig till bildskapande och genus kan uppstå om ett kritiskt sätt att tänka kring könsstere...

Digital Margins : How spatially and socially marginalized communities deal with digital exclusion

NARCIS (Netherlands)

Salemink, Koen

2016-01-01

The increasing importance of the Internet as a means of communication has transformed economies and societies. For spatially and socially marginalized communities, this transformation has resulted in digital exclusion and further marginalization. This book presents a study of two kinds of

Informing practice regarding marginalization: the application of the Koci Marginality Index.

Science.gov (United States)

Koci, Anne Floyd; McFarlane, Judith; Nava, Angeles; Gilroy, Heidi; Maddoux, John

2012-12-01

The 49th World Health Assembly of the World Health Organization (WHO) declared violence as the leading worldwide public health problem with a focus on the increase in the incidence of injuries to women. Violence against women is an international epidemic with specific instruments required to measure the impact on women's functioning. This article describes the application of the Koci Marginality Index (KMI), a 5-item scale to measure marginality, to the baseline data of a seven-year prospective study of 300 abused women: 150 first time users of a shelter and 150 first time applicants for a protection order from the justice system. Validity and reliability of the Koci Marginality Index and its usefulness for best clinical practice and for policy decisions for abused women's health are discussed. The 49th World Health Assembly of the World Health Organization (WHO) declared violence as the leading worldwide public health problem and focused on the increase in the incidence of injuries to women (Krug et al., 2002 ). Violence against women in the form of intimate partner violence (IPV) is costly in terms of dollars and health. In the United States in 2003, estimated costs of IPV approached $8.3 billion (Centers for Disease Control and Prevention [CDC], 2011). Outcomes related to severity of IPV vary but in 2003 victims suffering severe IPV lost nearly 8 million days of paid work, and greater than 5 million days of household productivity annually (CDC, 2011). Besides the evident financial cost of IPV, research confirms that exposure to IPV impacts a woman's health immediately and in the long-term (Breiding, Black, & Ryan, 2008 ; Campbell, 2002 ; CDC, 2011). Such sequela adversely affect the health of women and may increase their marginalization, a concept akin to isolation that may further increase negative effects on health outcomes. Immigrant women are at high risk for IPV (Erez, 2002 ) and those without documentation are at higher risk for marginalization (Montalvo

Comparative diversity of ammonia oxidizer 16S rRNA gene sequences in native, tilled, and successional soils

NARCIS (Netherlands)

Bruns, M.A.; Stephen, J.R.; Kowalchuk, G.A.; Prosser, J.I.; Paul, E.A.

1999-01-01

Autotrophic ammonia oxidizer (AAO) populations in soils from native, tilled, and successional treatments at the Kellogg Biological Station Long-Term Ecological Research site in southwestern Michigan were compared to assess effects of disturbance on these bacteria. N fertilization effects on AAO

Characterization of sand lenses and their role for subsurface transport in low-permeability clay tills

DEFF Research Database (Denmark)

Kessler, Timo Christian; Klint, K. E.; Nilsson, B.

2011-01-01

Glacial sediments dominate large parts of the geological topology in Denmark. They predominantly consist of lowpermeability tills, but fractures and sand-lenses constitute zones of enhanced permeability facilitating preferential flow. This study focuses on characterization of sand deposits with r...... the sand lenses in hydro-geological models to successfully characterize subsurface flow and transport, e.g. for remediation activities....

Using Winter Annual Cover Crops in a Virginia No-till Cotton Production System

OpenAIRE

Daniel, James B. II

1997-01-01

Cotton (Gossypium hirsutum L.) is a low residue crop, that may not provide sufficient surface residue to reduce erosion and protect the soil. A winter annual cover crop could alleviate erosion between cotton crops. Field experiments were conducted to evaluate selected winter annual cover crops for biomass production, ground cover, and N assimilation. The cover crop treatments were monitored under no-till and conventional tillage systems for the effects on soil moisture, cotton yield and qu...

Experiments on criticality carried out from 1975 till 1980

International Nuclear Information System (INIS)

Heinicke, W.; Tischer, A.; Weber, W.J.

1981-11-01

The report on hand includes the experiments on criticality published from 1975 till 1980. About 90 experiments with the most important related data are listed. They are capable of being called up, with the data base system KRITEXP, by 14 different descriptors or printed in any arrangement or order. This is the basis for a global or purposeful verification of the calculating method for criticality safety. The proof of reliability of the calculations for the criticality analysis are immediately relevant for the licencing procedure under atomic law for all plants of the nuclear fuel cycle where nuclear fuels are handled. Since no criticality experiments are being carried out in the Federal Republic of Germany, the data collection on hand will help to fill this gap with regard to the assessment of experiments carried out in other countries. (orig.) [de

Qualitative attributes and postharvest conservation of green ears of maize grown on different cover crops in organic no-till system

Directory of Open Access Journals (Sweden)

Luiz Fernando Favarato

Full Text Available ABSTRACT Postharvest quality of sweet maize varies depending on the type of seed, soil, quality of fertilizer, climatic conditions, and stage of maturation. This study aimed to evaluate the post-harvest quality and shelf life of green ears of maize grown on three soil covers in organic no-till sytem. The study was conducted in the municipality of Domingos Martins, ES (20° 22'16.91" S and 41° 03' 41.83" W. The experiment was arranged in a randomized block design with six replications and five treatments, consisting of three cover crops in organic no-till system: black-oat straw, white lupin, oat/lupin intercrop and two systems, organic and conventional, without straw. Maize double hybrid AG-1051 was sown in a spacing of 1.00 x 0.20 m. The variables evaluated included relative percentage of grain, straw and cob, pH, titratable acidity, soluble solids, grain moisture and shelf life. The use of different straws in the organic no-till system does not influence the postharvest quality of green ears. Ears packed in polystyrene trays with plastic film are suitable for marketing until the fifth day of storage at room temperature.

Task Group on Safety Margins Action Plan (SMAP). Safety Margins Action Plan - Final Report

International Nuclear Information System (INIS)

Hrehor, Miroslav; Gavrilas, Mirela; Belac, Josef; Sairanen, Risto; Bruna, Giovanni; Reocreux, Michel; Touboul, Francoise; Krzykacz-Hausmann, B.; Park, Jong Seuk; Prosek, Andrej; Hortal, Javier; Sandervaag, Odbjoern; Zimmerman, Martin

2007-01-01

The international nuclear community has expressed concern that some changes in existing plants could challenge safety margins while fulfilling all the regulatory requirements. In 1998, NEA published a report by the Committee on Nuclear Regulatory Activities on Future Nuclear Regulatory Challenges. The report recognized 'Safety margins during more exacting operating modes' as a technical issue with potential regulatory impact. Examples of plant changes that can cause such exacting operating modes include power up-rates, life extension or increased fuel burnup. In addition, the community recognized that the cumulative effects of simultaneous changes in a plant could be larger than the accumulation of the individual effects of each change. In response to these concerns, CSNI constituted the safety margins action plan (SMAP) task group with the following objectives: 'To agree on a framework for integrated assessments of the changes to the overall safety of the plant as a result of simultaneous changes in plant operation / condition; To develop a CSNI document which can be used by member countries to assess the effect of plant change on the overall safety of the plant; To share information and experience.' The two approaches to safety analysis, deterministic and probabilistic, use different methods and have been developed mostly independently of each other. This makes it difficult to assure consistency between them. As the trend to use information on risk (where the term risk means results of the PSA/PRA analysis) to support regulatory decisions is growing in many countries, it is necessary to develop a method of evaluating safety margin sufficiency that is applicable to both approaches and, whenever possible, integrated in a consistent way. Chapter 2 elaborates on the traditional view of safety margins and the means by which they are currently treated in deterministic analyses. This chapter also discusses the technical basis for safety limits as they are used today

Herbicide-tolerant Transgenic Soybean over 15 Years of Cultivation: Pesticide Use, Weed Resistance, and Some Economic Issues. The Case of the USA

Directory of Open Access Journals (Sweden)

Sylvie Bonny

2011-08-01

Full Text Available Genetically modified (GM herbicide-tolerant (HT crops have been largely adopted where they have been authorized. Nevertheless, they are fiercely criticized by some, notably because of the herbicide use associated with them. However, how much herbicide is applied to GMHT crops compared to conventional crops, and what impacts does the use of herbicide have? The paper first presents some factors explaining the predominance of GMHT crops. Then, trends in the use of herbicide for GM crops are studied in the case of the most widespread HT crop: HT soybean in the USA. The trends in the toxicity of herbicides applied to HT soybean are also addressed, as well as the appearance of glyphosate-resistant (GR weeds. Lastly, the paper examines the spread of GR weeds and its impact. How are farmers, weed scientists, and the industry coping with this development, and what are the prospects of glyphosate-tolerant crops given weed resistance? In conclusion, some issues of sustainability and innovation governance raised by genetically modified herbicide-tolerant crops are discussed.

Allelopathic influence of a wheat or rye cover crop on growth and yield of no-till cotton

Science.gov (United States)

TECHNICAL ABSTRACT No-till planting cotton into small grain cover crops has many benefits including reducing soil erosion and allelopathic suppression of weeds. It is suggested that the potentials of allelopathy on cotton plants. Nevertheless, little is known about the actual effects of alleloche...

Margin improvement initiatives: realistic approaches

Energy Technology Data Exchange (ETDEWEB)

Chan, P.K.; Paquette, S. [Royal Military College of Canada, Chemistry and Chemical Engineering Dept., Kingston, ON (Canada); Cunning, T.A. [Department of National Defence, Ottawa, ON (Canada); French, C.; Bonin, H.W. [Royal Military College of Canada, Chemistry and Chemical Engineering Dept., Kingston, ON (Canada); Pandey, M. [Univ. of Waterloo, Waterloo, ON (Canada); Murchie, M. [Cameco Fuel Manufacturing, Port Hope, ON (Canada)

2014-07-01

With reactor core aging, safety margins are particularly tight. Two realistic and practical approaches are proposed here to recover margins. The first project is related to the use of a small amount of neutron absorbers in CANDU Natural Uranium (NU) fuel bundles. Preliminary results indicate that the fuelling transient and subsequent reactivity peak can be lowered to improve the reactor's operating margins, with minimal impact on burnup when less than 1000 mg of absorbers is added to a fuel bundle. The second project involves the statistical analysis of fuel manufacturing data to demonstrate safety margins. Probability distributions are fitted to actual fuel manufacturing datasets provided by Cameco Fuel Manufacturing, Inc. They are used to generate input for ELESTRES and ELOCA. It is found that the fuel response distributions are far below industrial failure limits, implying that margin exists in the current fuel design. (author)

Nitrogen source effects on soil nitrous oxide emissions from strip-till corn.

Science.gov (United States)

Halvorson, Ardell D; Del Grosso, Stephen J; Jantalia, Claudia Pozzi

2011-01-01

Nitrogen (N) application to crops generally results in increased nitrous oxide (NO) emissions. Commercially available, enhanced-efficiency N fertilizers were evaluated for their potential to reduce NO emissions from a clay loam soil compared with conventionally used granular urea and urea-ammonium nitrate (UAN) fertilizers in an irrigated strip-till (ST) corn ( L.) production system. Enhanced-efficiency N fertilizers evaluated were a controlled-release, polymer-coated urea (ESN), stabilized urea, and UAN products containing nitrification and urease inhibitors (SuperU and UAN+AgrotainPlus), and UAN containing a slow-release N source (Nfusion). Each N source was surface-band applied (202 kg N ha) at corn emergence and watered into the soil the next day. A subsurface-band ESN treatment was included. Nitrous oxide fluxes were measured during two growing seasons using static, vented chambers and a gas chromatograph analyzer. All N sources had significantly lower growing season NO emissions than granular urea, with UAN+AgrotainPlus and UAN+Nfusion having lower emissions than UAN. Similar trends were observed when expressing NO emissions on a grain yield and N uptake basis. Loss of NO-N per kilogram of N applied was <0.8% for all N sources. Corn grain yields were not different among N sources but greater than treatments with no N applied. Selection of N fertilizer source can be a mitigation practice for reducing NO emissions in strip-till, irrigated corn in semiarid areas. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

UK consumer perceptions of a novel till-receipt 'traffic-light' nutrition system.

Science.gov (United States)

Cole, Matthew; Peek, Hayden; Cowen, Daniel

2018-03-26

Front-of-pack (FoP) traffic light nutrition labelling has been widely proposed as a tool to improve public health nutrition. Current evidence suggests that whilst consumers generally find them to be useful and an important source of information about a particular food or ingredient, this may have limited value in isolation when considering a person's overall nutritional intake. This study sought to examine UK consumers' use of existing FoP traffic light food labelling and ascertain public perception of a novel 'till-receipt' summary providing nutritional information about consumers entire shopping purchases. In total, 237 respondents completed an online questionnaire between May and June 2016. Almost two-thirds were female (n = 152, 64.1%) and the largest proportion of responses were received from those aged 25-32 years (n = 53, 22.4%) and 41-50 years (n = 53, 22.4%). About 83.5% of respondents suggested that they currently use traffic light information to inform their food purchases and 'health' was reported as the most important factor influencing food choice (42.2%; n = 100). Notably, 54.4% of respondents indicated that the novel till-receipt system could provide a solution to the potential limitations of existing FoP labelling and could help inform healthier food purchases. Our findings strengthen the existing evidence base to suggest that traffic light information is a useful tool to aid consumer food purchases. Moreover, our outcomes propose that consumers may benefit from a new receipt-based traffic light system which provides a more holistic summary of their entire food purchases.

The marginal costs of greenhouse gas emissions

International Nuclear Information System (INIS)

Tol, R.S.J.

1999-01-01

Estimates of the marginal costs of greenhouse gas emissions are on important input to the decision how much society would want to spend on greenhouse gas emission reduction. Marginal cost estimates in the literature range between $5 and $25 per ton of carbon. Using similar assumptions, the FUND model finds marginal costs of $9--23/tC, depending on the discount rate. If the aggregation of impacts over countries accounts for inequalities in income distribution or for risk aversion, marginal costs would rise by about a factor of 3. Marginal costs per region are an order of magnitude smaller than global marginal costs. The ratios between the marginal costs of CO 2 and those of CH 4 and N 2 O are roughly equal to the global warming potentials of these gases. The uncertainty about the marginal costs is large and right-skewed. The expected value of the marginal costs lies about 35% above the best guess, the 95-percentile about 250%

Four planting devices for planting no-till maize

Directory of Open Access Journals (Sweden)

Osei Bonsu Patterson

2015-05-01

Full Text Available An experiment was conducted at the CSIR-Crops Research Institute (CSIR-CRI Experimental station at Ejura in Ghana to compare the efficiency of four devices for planting no-till maize: Tractor drawn seeder, Chinese made jab planter, Locally made jab planter and a Cutlass. It took two (2 hours 48 minutes to plant one hectare of maize with the tractor drawn seeder, which was significantly (p less than 1% faster than all the planting methods. Cutlass was the slowest planting device lasting more than 14 hours per hectare. There was no significant difference in planting time between the Chinese planter and local planter. Economic analysis showed that cutlass planting produced the highest net benefit, whilst tractor drawn seeder produced the least benefit. In this study cutlass planting was done with precision by collaborating farmers. In actual farm situation however, hired laborers (planting gangs often plant in haste which often results in poor plant population leading to low yields. Tractor drawn seeders or jab planters could reduce drudgery in planting and encourage farm expansion.

Refining margins: recent trends

International Nuclear Information System (INIS)

Baudoin, C.; Favennec, J.P.

1999-01-01

Despite a business environment that was globally mediocre due primarily to the Asian crisis and to a mild winter in the northern hemisphere, the signs of improvement noted in the refining activity in 1996 were borne out in 1997. But the situation is not yet satisfactory in this sector: the low return on invested capital and the financing of environmental protection expenditure are giving cause for concern. In 1998, the drop in crude oil prices and the concomitant fall in petroleum product prices was ultimately rather favorable to margins. Two elements tended to put a damper on this relative optimism. First of all, margins continue to be extremely volatile and, secondly, the worsening of the economic and financial crisis observed during the summer made for a sharp decline in margins in all geographic regions, especially Asia. Since the beginning of 1999, refining margins are weak and utilization rates of refining capacities have decreased. (authors)

[Minna Ahokas. Valistus suomalaisessa kirjakulttuurissa 1700-luvulla. Bidrag till kännedom av Finlands natur och folk 188] / Tuija Laine

Index Scriptorium Estoniae

Laine, Tuija, 1964-

2012-01-01

Arvustus: Minna Ahokas. Valistus suomalaisessa kirjakulttuurissa 1700-luvulla. Bidrag till kännedom av Finlands natur och folk 188. Diss. Sasatamala : Finska Vetenskaps-societeten. (Suomen Tiedeseura, 2011)

Margin Requirements and Equity Option Returns

DEFF Research Database (Denmark)

Hitzemann, Steffen; Hofmann, Michael; Uhrig-Homburg, Marliese

In equity option markets, traders face margin requirements both for the options themselves and for hedging-related positions in the underlying stock market. We show that these requirements carry a significant margin premium in the cross-section of equity option returns. The sign of the margin...... premium depends on demand pressure: If end-users are on the long side of the market, option returns decrease with margins, while they increase otherwise. Our results are statistically and economically significant and robust to different margin specifications and various control variables. We explain our...... findings by a model of funding-constrained derivatives dealers that require compensation for satisfying end-users’ option demand....

Margin Requirements and Equity Option Returns

DEFF Research Database (Denmark)

Hitzemann, Steffen; Hofmann, Michael; Uhrig-Homburg, Marliese

In equity option markets, traders face margin requirements both for the options themselves and for hedging-related positions in the underlying stock market. We show that these requirements carry a significant "margin premium" in the cross-section of equity option returns. The sign of the margin...... premium depends on demand pressure: If end-users are on the long side of the market, option returns decrease with margins, while they increase otherwise. Our results are statistically and economically significant and robust to different margin specifications and various control variables. We explain our...... findings by a model of funding-constrained derivatives dealers that require compensation for satisfying end-users’ option demand....

Decoding the Margins: What Can the Fractal Geometry of Basaltic Flow Margins Tell Us?

Science.gov (United States)

Schaefer, E. I.; Hamilton, C.; Neish, C.; Beard, S. P.; Bramson, A. M.; Sori, M.; Rader, E. L.

2016-12-01

Studying lava flows on other planetary bodies is essential to characterizing eruption styles and constraining the bodies' thermal evolution. Although planetary basaltic flows are common, many key features are not resolvable in orbital imagery. We are thus developing a technique to characterize basaltic flow type, sub-meter roughness, and sediment mantling from these data. We will present the results from upcoming fieldwork at Craters of the Moon National Monument and Preserve with FINESSE (August) and at Hawai'i Volcanoes National Park (September). We build on earlier work that showed that basaltic flow margins are approximately fractal [Bruno et al., 1992; Gaonac'h et al., 1992] and that their fractal dimensions (D) have distinct `a`ā and pāhoehoe ranges under simple conditions [Bruno et al., 1994]. Using a differential GPS rover, we have recently shown that the margin of Iceland's 2014 Holuhraun flow exhibits near-perfect (R2=0.9998) fractality for ≥24 km across dm to km scales [Schaefer et al., 2016]. This finding suggests that a fractal-based technique has significant potential to characterize flows at sub-resolution scales. We are simultaneously seeking to understand how margin fractality can be modified. A preliminary result for an `a'ā flow in Hawaii's Ka'ū Desert suggests that although aeolian mantling obscures the original flow margin, the apparent margin (i.e., sediment-lava interface) remains fractal [Schaefer et al., 2015]. Further, the apparent margin's D is likely significantly modified from that of the original margin. Other factors that we are exploring include erosion, transitional flow types, and topographic confinement. We will also rigorously test the intriguing possibility that margin D correlates with the sub-meter Hurst exponent H of the flow surface, a common metric of roughness scaling [e.g., Shepard et al., 2001]. This hypothesis is based on geometric arguments [Turcotte, 1997] and is qualitatively consistent with all results so far.

Influence of cover crops on arthropods, free-living nematodes, and yield in a succeeding no-till soybean crop

Science.gov (United States)

Production practices that incorporate fall-planted cover crops into no-till agronomic crop rotations have become increasingly popular across the Northeastern United States for weed suppression and enhancing environmental stewardship. Field experiments were conducted in 2011 and 2012 to investigate e...

Long-term monitoring of nitrate transport to drainage from three agricultural clayey till fields

Science.gov (United States)

Ernstsen, V.; Olsen, P.; Rosenbom, A. E.

2015-08-01

The application of nitrogen (N) fertilisers to crops grown on tile-drained fields is required to sustain most modern crop production, but it poses a risk to the aquatic environment since tile drains facilitate rapid transport pathways with no significant reduction in nitrate. To maintain the water quality of the aquatic environment and the provision of food from highly efficient agriculture in line with the EU's Water Framework Directive and Nitrates Directive, field-scale knowledge is essential for introducing water management actions on-field or off-field and producing an optimal differentiated N-regulation in future. This study strives to provide such knowledge by evaluating on 11 years of nitrate-N concentration measurements in drainage from three subsurface-drained clayey till fields (1.3-2.3 ha) representing approximately 71 % of the surface sediments in Denmark dominated by clay. The fields differ in their inherent hydrogeological field settings (e.g. soil-type, geology, climate, drainage and groundwater table) and the agricultural management of the fields (e.g. crop type, type of N fertilisers and agricultural practices). The evaluation revealed three types of clayey till fields characterised by: (i) low net precipitation, high concentration of nitrate-N, and short-term low intensity drainage at air temperatures often below 5 °C; (ii) medium net precipitation, medium concentration of nitrate-N, and short-term medium-intensity drainage at air temperatures often above 5 °C; and (iii) high net precipitation, low concentration of nitrate-N and long-term high intensity drainage at air temperatures above 5 °C. For each type, on-field water management actions, such as the selection of crop types and introduction of catch crops, appeared relevant, whereas off-field actions only seemed relevant for the latter two field types given the temperature-dependent reduction potential of nitrate off-field. This initial well-documented field-scale knowledge from fields

Indicators of soil quality in the implantation of no-till system with winter crops.

OpenAIRE

NOGUEIRA, M. A.; TELLES, T. S.; FAGOTTI, D. dos S. L.; BRITO, O. R.; PRETE, C. E. C.; GUIMARÃES, M. de F.

2014-01-01

We assessed the effect of different winter crops on indicators of soil quality related to C and N cycling and C fractions in a Rhodic Kandiudult under no-till system at implantation, during two growing seasons, in Londrina PR Brazil. The experimental design was randomized blocks with split-plot in time arrangement, with four replications. The parcels were the winter crops: multicropping of cover crops with black oat (Avena strigosa), hairy vetch (Vicia villosa) and fodder radish (Raphanus sat...

Viljan till fysisk aktivitet : en intervention avsedd att stimulera ungdomar att bli fysiskt aktiva

OpenAIRE

Isberg, Jenny

2009-01-01

Jenny Isberg (2009): Viljan till fysisk aktivitet – en intervention avsedd att stimulera ungdomar att bli fysiskt aktiva. Örebro Studies in Sport Sciences 6, 141 pp. Physical education (PE) at school may play an important role in the process of becoming physically active in the adolescence and in developing a physically active lifestyle. The opportunities for teachers to provide positive physical activity experiences to the student population extend regularly over the school terms. For some s...

Splenic marginal zone lymphoma.

Science.gov (United States)

Piris, Miguel A; Onaindía, Arantza; Mollejo, Manuela

Splenic marginal zone lymphoma (SMZL) is an indolent small B-cell lymphoma involving the spleen and bone marrow characterized by a micronodular tumoral infiltration that replaces the preexisting lymphoid follicles and shows marginal zone differentiation as a distinctive finding. SMZL cases are characterized by prominent splenomegaly and bone marrow and peripheral blood infiltration. Cells in peripheral blood show a villous cytology. Bone marrow and peripheral blood characteristic features usually allow a diagnosis of SMZL to be performed. Mutational spectrum of SMZL identifies specific findings, such as 7q loss and NOTCH2 and KLF2 mutations, both genes related with marginal zone differentiation. There is a striking clinical variability in SMZL cases, dependent of the tumoral load and performance status. Specific molecular markers such as 7q loss, p53 loss/mutation, NOTCH2 and KLF2 mutations have been found to be associated with the clinical variability. Distinction from Monoclonal B-cell lymphocytosis with marginal zone phenotype is still an open issue that requires identification of precise and specific thresholds with clinical meaning. Copyright © 2016 Elsevier Ltd. All rights reserved.

Categorical marginal models: quite extensive package for the estimation of marginal models for categorical data

OpenAIRE

Wicher Bergsma; Andries van der Ark

2015-01-01

A package accompanying the book Marginal Models for Dependent, Clustered, and Longitudinal Categorical Data by Bergsma, Croon, & Hagenaars, 2009. It’s purpose is fitting and testing of marginal models.

Characterizing Convexity of Games using Marginal Vectors

NARCIS (Netherlands)

van Velzen, S.; Hamers, H.J.M.; Norde, H.W.

2003-01-01

In this paper we study the relation between convexity of TU games and marginal vectors.We show that if specfic marginal vectors are core elements, then the game is convex.We characterize sets of marginal vectors satisfying this property, and we derive the formula for the minimum number of marginal

PRACT (Prototyping Rotation and Association with Cover crop and no Till) - a tool for designing conservation agriculture systems

NARCIS (Netherlands)

Naudin, K.; Husson, M.O.; Scopel, E.; Auzoux, S.; Giller, K.E.

2015-01-01

Moving to more agroecological cropping systems implies deep changes in the organization of cropping systems. We propose a method for formalizing the process of innovating cropping system prototype design using a tool called PRACT (Prototyping Rotation and Association with Cover crop and no Till)

12 CFR 220.4 - Margin account.

Science.gov (United States)

2010-01-01

... Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM CREDIT BY... securities. The required margin on a net long or net short commitment in a when-issued security is the margin...) Interest charged on credit maintained in the margin account; (ii) Premiums on securities borrowed in...

Conference Report: The New Discovery of Margins: Theory-Based Excursions in Marginal Social Fields

Directory of Open Access Journals (Sweden)

Babette Kirchner

2014-05-01

Full Text Available At this year's spring conference of the Sociology of Knowledge Section of the German Sociological Association, a diverse range of theoretical concepts and multiple empirical insights into different marginal social fields were presented. As in everyday life, drawing a line between center and margin can be seen as an important challenge that must equally be faced in sociology. The socially constructed borderline appears to be highly variable. Therefore it has to be delineated or fixed somehow. The construction of margins is necessary for society in general and smaller social groupings alike to confirm one's own "normal" identity, or one's own membership on the fringes. The different contributions exemplify what was established at the beginning of the conference: Namely that society and its margins are defined differently according to the empirical as well as conceptual focus. URN: http://nbn-resolving.de/urn:nbn:de:0114-fqs1402148

[Maria Bogucka. Woman in the history of Europe. From antiquity till the begin of the XXist century] / Aigi Heero

Index Scriptorium Estoniae

Heero, Aigi, 1971-

2009-01-01

Arvustus: Bogucka, Maria. Woman in the history of Europe. From antiquity till the begin of the XXist century. Warsaw, 2008. Maria Bogucka uurimus kirjeldab ülevaatlikult naiste rolli ja selle muutumist Euroopa ühiskonnas läbi aegade

Surficial geologic map of Berrien County, Michigan, and the adjacent offshore area of Lake Michigan

Science.gov (United States)

Stone, Byron D.; Kincare, Kevin A.; O'Leary, Dennis W.; Newell, Wayne L.; Taylor, Emily M.; Williams, Van S.; Lundstrom, Scott C.; Abraham, Jared E.; Powers, Michael H.

2017-12-13

, characterized as clayey till, loamy till, or sandy loamy till that are based in part on correlation of silty tills and clay mineralogy. The stratified morainic systems (local Valparaiso and Kalamazoo morainic systems) are composed of multiple ice-marginal glacial-lake deltas and glaciolacustrine fans that form a contiguous array of deposits, welded together at their onlapping contacts, further related by the accordant altitudes of their delta topset plains. Their bounding ice-contact slopes repeatedly are aligned parallel to the regional trend of the receding ice margin. Ice-marginal (ice-contact) deltas were deposited in glacial lakes that expanded northward as the ice sheet retreated. Glaciofluvial topset beds, which overlie deltaic foreset and bottomset facies, fine away from the ice margin. Stratified deposits associated with the Valparaiso moraine were deposited in glacial Lakes Madron and Dowagiac. Subsequent deposits of glacial Lake Baroda preceded basin-wide deposits associated with various levels of Lake Michigan.Sheet 2 includes a series of 10 map figures that show cut-away three-dimensional time slices of the stratigraphic succession, from basal tills on bedrock, to ice-marginal deltas in the three large proglacial lakes, to stacked till/lake-bottom deposits related to the Lake Border ice margin readvances, to young deposits of glacial Lake Chicago and younger phases of other glacial lakes and the Chippewa lake lowstand.The pamphlet contains a discussion of the stratigraphic framework, descriptions of each depositional unit, and graphic logs of U.S. Geological Survey stratigraphic drill holes. The pamphlet also relates the geologic history of Berrien County, beginning with bedrock Paleozoic marine deposits, continuing through erosional effects of multiple glaciations and the detailed steps of late Wisconsinan ice-margin recession as recorded in the moraines, and the rise and fall of postglacial lake levels in the Lake Michigan basin.

NRC Seismic Design Margins Program Plan

International Nuclear Information System (INIS)

Cummings, G.E.; Johnson, J.J.; Budnitz, R.J.

1985-08-01

Recent studies estimate that seismically induced core melt comes mainly from earthquakes in the peak ground acceleration range from 2 to 4 times the safe shutdown earthquake (SSE) acceleration used in plant design. However, from the licensing perspective of the US Nuclear Regulatory Commission, there is a continuing need for consideration of the inherent quantitative seismic margins because of, among other things, the changing perceptions of the seismic hazard. This paper discusses a Seismic Design Margins Program Plan, developed under the auspices of the US NRC, that provides the technical basis for assessing the significance of design margins in terms of overall plant safety. The Plan will also identify potential weaknesses that might have to be addressed, and will recommend technical methods for assessing margins at existing plants. For the purposes of this program, a general definition of seismic design margin is expressed in terms of how much larger that the design basis earthquake an earthquake must be to compromise plant safety. In this context, margin needs to be determined at the plant, system/function, structure, and component levels. 14 refs., 1 fig

E-shop 'til you drop : En studie över e-handlares anpassning av den fysiska köpprocessen till ett virtuellt sammanhang

OpenAIRE

Alcazar, Alexander; Kastås, Sandra

2011-01-01

Denna magisteruppsats behandlar e-handlares anpassning av en fysisk köpprocess till en virtuell. Med detta syftar vi mer specifikt på e-handlare av modekläder som i högre grad är beroende av en fysisk köpprocess. Vår frågeställning var således: Hur gör e-handlare inom klädbranschen för att anpassa den fysiska köpprocessen till ett virtuellt sammanhang? För att undersöka detta använde vi oss av Overbys artikel "Process Virtualization Theory and the Impact of Information Technology" från 2008 d...

The marginal band system in nymphalid butterfly wings.

Science.gov (United States)

Taira, Wataru; Kinjo, Seira; Otaki, Joji M

2015-01-01

Butterfly wing color patterns are highly complex and diverse, but they are believed to be derived from the nymphalid groundplan, which is composed of several color pattern systems. Among these pattern systems, the marginal band system, including marginal and submarginal bands, has rarely been studied. Here, we examined the color pattern diversity of the marginal band system among nymphalid butterflies. Marginal and submarginal bands are usually expressed as a pair of linear bands aligned with the wing margin. However, a submarginal band can be expressed as a broken band, an elongated oval, or a single dot. The marginal focus, usually a white dot at the middle of a wing compartment along the wing edge, corresponds to the pupal edge spot, one of the pupal cuticle spots that signify the locations of color pattern organizing centers. A marginal band can be expressed as a semicircle, an elongated oval, or a pair of eyespot-like structures, which suggest the organizing activity of the marginal focus. Physical damage at the pupal edge spot leads to distal dislocation of the submarginal band in Junonia almana and in Vanessa indica, suggesting that the marginal focus functions as an organizing center for the marginal band system. Taken together, we conclude that the marginal band system is developmentally equivalent to other symmetry systems. Additionally, the marginal band is likely a core element and the submarginal band a paracore element of the marginal band system, and both bands are primarily specified by the marginal focus organizing center.

Assessment of seismic margin calculation methods

International Nuclear Information System (INIS)

Kennedy, R.P.; Murray, R.C.; Ravindra, M.K.; Reed, J.W.; Stevenson, J.D.

1989-03-01

Seismic margin review of nuclear power plants requires that the High Confidence of Low Probability of Failure (HCLPF) capacity be calculated for certain components. The candidate methods for calculating the HCLPF capacity as recommended by the Expert Panel on Quantification of Seismic Margins are the Conservative Deterministic Failure Margin (CDFM) method and the Fragility Analysis (FA) method. The present study evaluated these two methods using some representative components in order to provide further guidance in conducting seismic margin reviews. It is concluded that either of the two methods could be used for calculating HCLPF capacities. 21 refs., 9 figs., 6 tabs

Employer branding på Q-Med : En fallstudie i hur företagsspecifika värden förmedlas till potentiella och befintliga medarbetare

OpenAIRE

Nilsson, Stina; Ljungmark, Erik

2011-01-01

Sammanfattning "Employer branding på Q-Med – En fallstudie i hur företagsspecifika värden förmedlas till potentiella och befintliga medarbetare" Datum: 19 januari, 2011 Nivå: Kandidatuppsats i företagsekonomi, 15 ECTS Institution: Akademin för hållbar samhälls‐ och teknikutveckling, HST, Mälardalens Högskola Författare: Erik Ljungmark 29 januari 1980, Stina Nilsson 25 april 1983 Titel: Employer branding på Q-Med – En fallstudie i hur företagsspecifika värden förmedlas till potentiella och...

MARGINS: Toward a novel science plan

Science.gov (United States)

Mutter, John C.

A science plan to study continental margins has been in the works for the past 3 years, with almost 200 Earth scientists from a wide variety of disciplines gathering at meetings and workshops. Most geological hazards and resources are found at continental margins, yet our understanding of the processes that shape the margins is meager.In formulating this MARGINS research initiative, fundamental issues concerning our understanding of basic Earth-forming processes have arisen. It is clear that a business-as-usual approach will not solve the class of problems defined by the MARGINS program; the solutions demand approaches different from those used in the past. In many cases, a different class of experiment will be required, one that is well beyond the capability of individual principle investigators to undertake on their own. In most cases, broadly based interdisciplinary studies will be needed.

Updated model for radionuclide transport in the near-surface till at Forsmark - Implementation of decay chains and sensitivity analyses

International Nuclear Information System (INIS)

Pique, Angels; Pekala, Marek; Molinero, Jorge; Duro, Lara; Trinchero, Paolo; Vries, Luis Manuel de

2013-02-01

The Forsmark area has been proposed for potential siting of a deep underground (geological) repository for radioactive waste in Sweden. Safety assessment of the repository requires radionuclide transport from the disposal depth to recipients at the surface to be studied quantitatively. The near-surface quaternary deposits at Forsmark are considered a pathway for potential discharge of radioactivity from the underground facility to the biosphere, thus radionuclide transport in this system has been extensively investigated over the last years. The most recent work of Pique and co-workers (reported in SKB report R-10-30) demonstrated that in case of release of radioactivity the near-surface sedimentary system at Forsmark would act as an important geochemical barrier, retarding the transport of reactive radionuclides through a combination of retention processes. In this report the conceptual model of radionuclide transport in the quaternary till at Forsmark has been updated, by considering recent revisions regarding the near-surface lithology. In addition, the impact of important conceptual assumptions made in the model has been evaluated through a series of deterministic and probabilistic (Monte Carlo) sensitivity calculations. The sensitivity study focused on the following effects: 1. Radioactive decay of 135 Cs, 59 Ni, 230 Th and 226 Ra and effects on their transport. 2. Variability in key geochemical parameters, such as the composition of the deep groundwater, availability of sorbing materials in the till, and mineral equilibria. 3. Variability in hydraulic parameters, such as the definition of hydraulic boundaries, and values of hydraulic conductivity, dispersivity and the deep groundwater inflow rate. The overarching conclusion from this study is that the current implementation of the model is robust (the model is largely insensitive to variations in the parameters within the studied ranges) and conservative (the Base Case calculations have a tendency to

Reliabilityy and operating margins of LWR fuels

International Nuclear Information System (INIS)

Strasser, A.A.; Lindquist, K.O.

1977-01-01

The margins to fuel thermal operating limits under normal and accident conditions are key to plant operating flexibility and impact on availability and capacity factor. Fuel performance problems that do not result in clad breach, can reduce these margins. However, most have or can be solved with design changes. Regulatory changes have been major factors in eroding these margins. Various methods for regaining the margins are discussed

Why does carbon increase in highly weathered soil under no-till upon lime and gypsum use?

Science.gov (United States)

Inagaki, Thiago Massao; de Moraes Sá, João Carlos; Caires, Eduardo Fávero; Gonçalves, Daniel Ruiz Potma

2017-12-01

Field experiments have been used to explain how soil organic carbon (SOC) dynamics is affected by lime and gypsum applications, however, how SOC storage occurs is still debatable. We hypothesized that although many studies conclude that Ca-based soil amendments such as lime and gypsum may lead to SOC depletion due to the enhancement of microbial activity, the same does not occur under conservation agriculture conditions. Thus, the objective of this study was to elucidate the effects of lime and gypsum applications on soil microbial activity and SOC stocks in a no-till field and in a laboratory incubation study simulating no-till conditions. The field experiment was established in 1998 in a clayey Oxisol in southern Brazil following a completely randomized blocks design with a split-plot arrangement and three replications. Lime and gypsum were surface applied in 1998 and reapplied in 2013. Undisturbed soil samples were collected before the treatments reapplications, and one year after. The incubation experiment was carried out during 16months using these samples adding crop residues on the soil surface to simulate no-till field conditions. Lime and gypsum applications significantly increased the labile SOC stocks, microbial activity and soil fertility attributes in both field and laboratory experiments. Although the microbial activity was increased, no depletion of SOC stocks was observed in both experiments. Positive correlations were observed between microbial activity increase and SOC gains. Labile SOC and Ca 2+ content increase leads to forming complex with mineral soil fractions. Gypsum applications performed a higher influence on labile SOC pools in the field than in the laboratory experiment, which may be related to the presence of active root system in the soil profile. We conclude that incubation experiments using lime and gypsum in undisturbed samples confirm that soil microbial activity increase does not deplete SOC stocks under conservation agriculture

Biochar Effects on Soil Aggregate Properties Under No-Till Maize

DEFF Research Database (Denmark)

Khademalrasoul, Ataalah; Naveed, Muhammad; Heckrath, Goswin Johann

2014-01-01

of biochar particles had higher TS and SRE probably because of bonding effects. Based on the improved soil aggregate properties, we suggest that biochar can be effective for increasing and sustaining overall soil quality, for example, related to minimizing the soil erosion potential.......Soil aggregates are useful indicators of soil structure and stability, and the impact on physical and mechanical aggregate properties is critical for the sustainable use of organic amendments in agricultural soil. In this work, we evaluated the short-term soil quality effects of applying biochar (0......–10 kg m−2), in combination with swine manure (2.1 and 4.2 kg m−2), to a no-till maize (Zea mays L.) cropping system on a sandy loam soil in Denmark. Topsoil (0–20 cm) aggregates were analyzed for clay dispersibility, aggregate stability, tensile strength (TS), and specific rupture energy (SRE) using end...

Response of Transplanted Aman Rice Varieties to Herbicides in Strip-Tilled Non-Puddled Soil

Directory of Open Access Journals (Sweden)

Taslima Zahan1

2017-12-01

Full Text Available BACKGROUND: Sensitivity of crop cultivars may vary to commonly used herbicides resulting in potential yield loss and reduce farm profit. Transplanting of rice seedlings in strip-tilled non-puddled field is a new practice for which herbicide tolerant varieties need to select. Therefore, a study was executed at the Agronomy Field Laboratory of Bangladesh Agricultural University, Mymensingh during 2013 to evaluate the response of some popular transplanted aman rice varieties to different herbicides at their recommended rate and to select most tolerant aman rice variety or varieties for strip-tilled non-puddled transplanting. METHODOLOGY: Twelve aman rice varieties (BR11, BRRI dhan33, BRRI dhan39, BRRI dhan44, BRRI dhan46, BRRI dhan49, BRRI dhan51, BRRI dhan52, BRRI dhan56, BRRI dhan57, BRRI hybrid dhan-4 and BINA dhan7 were examined in the study against six herbicides (2 pre-emergence: pyrazosulfuron-ethyl and butachlor; 1 early post-emergence: orthosulfamuron and 3 late post-emergence: acetochlor + bensulfuron methyl, butachlor + propanil and 2,4-D amine along with one untreated manually weed-free control. KEY FINDINGS: The study revealed that aman rice varieties responded differentially to different herbicides. All rice varieties performed better in pyrazosulfuron-ethyl treated plots relative to the other herbicide treated plots and even than the control plots. Pyrazosulfuron-ethyl increased grain yield of all aman rice varieties by 0.6-32.6% over control and butachlor + propanil provided increased grain yield in all rice varieties by 2.0-25.5% except BRRI hybrid dhan-4. The study also disclosed that BRRI dhan57 and BRRI hybrid dhan-4 gone through the yield loss by application of 2,4-D amine and BRRI dhan56 by application of butachlor and orthosulfamuron. Moreover, acetochlor + bensulfuron methyl produced shorter plants and caused yield loss by 7.8-27.1% in all aman rice varieties compared to the control and BRRI dhan39 was the most susceptible

Marginal cost application in the power industry

International Nuclear Information System (INIS)

Twardy, L.; Rusak, H.

1994-01-01

Two kind of marginal costs, the short-run and the long-run, are defined. The former are applied in conditions when the load increase is not accompanied neither by the increase of the transmission capacity not the installed capacity while the latter assume new investments to expand the power system. The long-run marginal costs be used to forecast optimized development of the system. They contain two main components: the marginal costs of capacity and the marginal costs of energy. When the long-run marginal costs are calculated, each component is considered for particular voltage levels, seasons of the year, hours of the day - selected depending on the system reliability factor as well as on its load level. In the market economy countries the long-run marginal costs can be used for setting up the electric energy tariffs. (author). 7 refs, 11 figs

Indicators of soil quality in the implantation of no-till system with winter crops

Directory of Open Access Journals (Sweden)

Marco Antonio Nogueira

Full Text Available We assessed the effect of different winter crops on indicators of soil quality related to C and N cycling and C fractions in a Rhodic Kandiudult under no-till system at implantation, during two growing seasons, in Londrina PR Brazil. The experimental design was randomized blocks with split-plot in time arrangement, with four replications. The parcels were the winter crops: multicropping of cover crops with black oat (Avena strigosa, hairy vetch (Vicia villosa and fodder radish (Raphanus sativus; sunflower (Heliantus annuus intercropped with Urochloa ruziziensis; corn (Zea mays intercropped with Urochloa; and corn; fodder radish; or wheat (Triticum aestivum as sole crops. The subplots were the years: 2008 and 2009. Determinations consisted of total organic C, labile and resistant C, total N, microbial biomass C and N, the C/N ratio of soil organic matter, and the microbial quotient (qMic, besides microbiological and biochemical attributes, assessed only in 2009. The attributes significantly changed with the winter crops, especially the multicropping of cover crops and fodder radish, as well as effect of years. Despite stimulating the microbiological/biochemical activity, fodder radish cropping decreased the soil C in the second year, likewise the wheat cropping. The multicropping of cover crops in winter is an option for management in the establishment of no-till system, which contributes to increase the concentrations of C and stimulate the soil microbiological/biochemical activity.

Workers' marginal costs of commuting

DEFF Research Database (Denmark)

van Ommeren, Jos; Fosgerau, Mogens

2009-01-01

This paper applies a dynamic search model to estimate workers' marginal costs of commuting, including monetary and time costs. Using data on workers' job search activity as well as moving behaviour, for the Netherlands, we provide evidence that, on average, workers' marginal costs of one hour...

Reply to `Comment on "The beginnings of hydrous mantle wedge melting" by Till et al.' by Green, Rosenthal and Kovacs

Science.gov (United States)

Till, Christy B.; Grove, Timothy L.; Withers, Anthony C.

2012-12-01

The comment of Green et al. debates the interpretation of the temperature of the H2O-saturated peridotite solidus and presence of silicate melt in the experiments of Till et al. (Contrib Mineral Petrol 163:669-688, 2012) at <1,000 °C. The criticisms presented in their comment do not invalidate any of the most compelling observations of Till et al. (Contrib Mineral Petrol 163:669-688, 2012) as discussed in the following response, including the changing minor element and Mg# composition of the solid phases with increasing temperature in our experiments with 14.5 wt% H2O at 3.2 GPa, as well as the results of our chlorite peridotite melting experiments with 0.7 wt% H2O. The point remains that Till et al. (Contrib Mineral Petrol 163:669-688, 2012) present data that call into question the H2O-saturated peridotite solidus temperature preferred by Green (Tectonophysics 13(1-4):47-71, 1972; Earth Planet Sci Lett 19(1):37-53, 1973; Can Miner 14:255-268, 1976); Millhollen et al. (J Geol 82(5):575-587, 1974); Mengel and Green (Stability of amphibole and phlogopite in metasomatized peridotite under water-saturated and water-undersaturated conditions, Geological Society of Australia Special Publication, Blackwell, pp 571-581, 1989); Wallace and Green (Mineral Petrol 44:1-19, 1991) and Green et al. (Nature 467(7314):448-451, 2010).

Discovering and verifying DNA polymorphisms in a mung bean [V. radiata (L. R. Wilczek] collection by EcoTILLING and sequencing

Directory of Open Access Journals (Sweden)

Dean Rob E

2008-06-01

Full Text Available Abstract Background Vigna radiata, which is classified in the family Fabaceae, is an important economic crop and a dietary staple in many developing countries. The species radiata can be further subdivided into varieties of which the variety sublobata is currently acknowledged as the putative progenitor of radiata. EcoTILLING was employed to identify single nucleotide polymorphisms (SNPs and small insertions/deletions (INDELS in a collection of Vigna radiata accessions. Findings A total of 157 DNA polymorphisms in the collection were produced from ten primer sets when using V. radiata var. sublobata as the reference. The majority of polymorphisms detected were found in putative introns. The banding patterns varied from simple to complex as the number of DNA polymorphisms between two pooled samples increased. Numerous SNPs and INDELS ranging from 4–24 and 1–6, respectively, were detected in all fragments when pooling V. radiata var. sublobata with V. radiata var. radiata. On the other hand, when accessions of V. radiata var. radiata were mixed together and digested with CEL I relatively few SNPs and no INDELS were detected. Conclusion EcoTILLING was utilized to identify polymorphisms in a collection of mung bean, which previously showed limited molecular genetic diversity and limited morphological diversity in the flowers and pod descriptors. Overall, EcoTILLING proved to be a powerful genetic analysis tool providing the rapid identification of naturally occurring variation.

Metoder och verktyg för motivation till och integration av arbetsmiljöarbete

OpenAIRE

Åteg, Mattias; Nygren, Olle; Andersson, Ing-Marie; Laring, Jonas; Neely, Greg; Rosén, Gunnar

2006-01-01

Rapporten utgår från forskningsområdet "Hur kan och bör arbetsmiljöarbete bedrivas och integreras i organisationers kärnverksamhet?" vid tema SMARTA, Arbetslivsinstitutet. I ett tidigare arbete har ett antal egenskaper identifierats som viktiga för motivation och engagemang för arbetsmiljöarbete, sk Moveit-egenskaper. Dessa egenskaper och deras roll i arbetsmiljöarbetet ställs här i relation till perspektivet integrerat arbetsmiljöarbete, där arbetsmiljön ingår i styrsystemet och arbetsmiljöa...

Pathology of nodal marginal zone lymphomas.

Science.gov (United States)

Pileri, Stefano; Ponzoni, Maurilio

Nodal marginal zone B cell lymphomas (NMZLs) are a rare group of lymphoid disorders part of the spectrum of marginal zone B-cell lymphomas, which encompass splenic marginal one B-cell lymphoma (SMZL) and extra nodal marginal zone of B-cell lymphoma (EMZL), often of MALT-type. Two clinicopathological forms of NMZL are recognized: adult-type and pediatric-type, respectively. NMZLs show overlapping features with other types of MZ, but distinctive features as well. In this review, we will focus on the salient distinguishing features of NMZL mostly under morphological/immunophenotypical/molecular perspectives in views of the recent acquisitions and forthcoming updated 2016 WHO classification of lymphoid malignancies. Copyright © 2016 Elsevier Ltd. All rights reserved.

Long-term seismic observations along Myanmar-Sunda subduction margin: insights for 2004 M w > 9.0 earthquake

Science.gov (United States)

Khan, Prosanta Kumar; Banerjee, Jayashree; Shamim, Sk; Mohanty, Manoranjan

2018-03-01

The present study investigates the temporal variation of few seismic parameters between the Myanmar (Zone I), Andaman-Nicobar-Northwest Sumatra (Zone II), Southeast Sumatra-West Indonesia (Zone III) and East Indonesia (Zone IV) converging boundaries in reference to the generation of 26 December 2004 M w > 9.0 off-Sumatra mega-earthquake event. The four segments are distinguished based on tectonics parameters, distinct geological locations, great earthquake occurrences, and the Wadati-Benioff zone characteristics. Two important seismic parameters such as seismic energy and b values are computed over a time-window of 6-month period during the entire 1976-2013 period for these segments. The b values show a constant decrease in Zones II, III, and IV, whereas the Zone I does not show any such pattern prior to the 2004 mega-event. The release of seismic energy was also gradually decreasing in Zones II and III till the 2004 event, and little similar pattern was also noted in Zone IV. This distinct observation might be indicating that the stress accumulation was dominant near the Sumatra-Java area located towards southeast of Zone II and northwest of Zone III. The released strain energy during the 2004 event was subsequently migrated towards north, rupturing 1300 km of the boundary between the Northwest Sumatra and the North Andaman. The occurrence of 2004 mega-event was apparently concealed behind the long-term seismic quiescence existing near the Sumatra and Nicobar margin. A systematic study of the patterns of seismic energy release and b values, and the long-term observation of collective behaviour of the margin tectonics might have had given clues to the possibility of the 2004 mega-event.

A meta-analysis of pesticide loss in runoff under conventional tillage and no-till management.

Science.gov (United States)

Elias, Daniel; Wang, Lixin; Jacinthe, Pierre-Andre

2018-01-12

Global agricultural intensification has led to increased pesticide use (37-fold from 1960 to 2005) and soil erosion (14% since 2000). Conservation tillage, including no-till (NT), has been proposed as an alternative to conventional plow till (PT) to mitigate soil erosion, but past studies have reported mixed results on the effect of conservation tillage on pesticide loss. To explore the underlying factors of these differences, a meta-analysis was conducted using published data on pesticide concentration and load in agricultural runoff from NT and PT fields. Peer-reviewed articles (1985-2016) were compiled to build a database for analysis. Contrary to expectations, results showed greater concentration of atrazine, cyanazine, dicamba, and simazine in runoff from NT than PT fields. Further, we observed greater load of dicamba and metribuzin, but reduced load of alachlor from NT fields. Overall, the concentration and the load of pesticides were greater in runoff from NT fields, especially pesticides with high solubility and low affinity for solids. Thus, NT farming affects soil properties that control pesticide retention and interactions with soils, and ultimately their mobility in the environment. Future research is needed for a more complete understanding of pesticide-soil interactions in NT systems. This research could inform the selection of pesticides by farmers and improve the predictive power of pesticide transport models.

Biodiversity and agro-ecology in field margins.

Science.gov (United States)

De Cauwer, B; Reheul, D; Nijs, I; Milbau, A

2005-01-01

This multidisciplinary study investigates agro-ecological functions (nature conservation, agriculture, environment) and implications of newly created, mown sown and unsown field margin strips installed on ex-arable land to increase biodiversity. From conservational concern, the development of species rich field margin strips was not strongly affected by the installed type of margin strip since species diversity converged over time, whether strips were sown or not. Convergence between unsown and sown margin strips occurred also in terms of species composition: unsown and sown strips became similar over time. Mowing without removal of cuttings significantly reduced species richness, yielded more grassy margin strips and delayed similarity in species composition between sown and unsown margin strips. Species richness on the longer term was not significantly affected by light regime nor by disturbance despite significant temporary effects shortly after the disturbance event. On the contrary vegetation composition in terms of importance of functional groups changed after disturbance: the share of spontaneous species within functional groups increased resulting in higher similarity between the sown and unsown vegetation. Furthermore risk of invasion was highest in the disturbed unsown community on the unshaded side of a tree lane. A positive effect of botanical diversity on insect number and diversity was found. However the effects of botanical diversity on insect number was mediated by light regime. At high light availability differences between plant communities were more pronounced compared to low light availablilty. The abundance of some insect families was dependent on the vegetation composition. Furthermore light availability significantly influenced insect diversity as well as the spatial distribution of families. From agricultural concern, installing margin strips by sowing a species mixture and a mowing regime with removal of cuttings are good practices to

An extensive permanent snowfield and the possible occurrence of permafrost in till in the Ridnitvsohkka area, Finnish Lapland

Directory of Open Access Journals (Sweden)

Heikki Hirvas

2000-01-01

Full Text Available An area of permanent snow and frozen ground was studied at the end of summer seasons during the years 1990–1993 near the summit of Ridnitvsohkka fell, which at 1317 m a.s.l. is the second highest peak in Finland. The eastern flank of Ridnitvsohkka has the most extensive area of permanent snow (3 km^2 in Finland, while the summit region represents the highest single area of basal till devoid of vegetation cover and displaying patterned ground features.The ground penetrating radar results show that the form of the snowfield does not conform to the topography of the underlying bedrock and reveal the presence of several continuous reflectors dipping down-slope. Observations based on drilling and a single test pit indicate that the snowfield is 6.2 m thick and that it contains discontinuous lenses or layers of ice from 2 to 30 mm in thickness. Plant material from the depth of 4.05 m in the drilling core yielded a radiocarbon age of 35 years, while variations in the size of lichens growing at the edge of the snowfield indicated that the snowfield was of considerably greater extent some 100 to 150 years ago. The results suggest that the snowfield has been stable for a relatively long period but the “residence time” of snow in thesnowfield is rather short, presumably less than 100 years and possibly only a few decades.Percussion drilling on the Ridnitvsohkka summit plateau, situating 1290 m a.s.l., revealed that the till was frozen at the depth of 1.9 m at the end of July 1993. Discovery of frozen till shows that frozen ground can locally survive from one season to the next, while the extent of the permanent snowfield and vegetation-free patterned ground suggest that the conditions favourable for permafrost mighthave existed over wider areas.

Updated model for radionuclide transport in the near-surface till at Forsmark - Implementation of decay chains and sensitivity analyses

Energy Technology Data Exchange (ETDEWEB)

Pique, Angels; Pekala, Marek; Molinero, Jorge; Duro, Lara; Trinchero, Paolo; Vries, Luis Manuel de [Amphos 21 Consulting S.L., Barcelona (Spain)

2013-02-15

The Forsmark area has been proposed for potential siting of a deep underground (geological) repository for radioactive waste in Sweden. Safety assessment of the repository requires radionuclide transport from the disposal depth to recipients at the surface to be studied quantitatively. The near-surface quaternary deposits at Forsmark are considered a pathway for potential discharge of radioactivity from the underground facility to the biosphere, thus radionuclide transport in this system has been extensively investigated over the last years. The most recent work of Pique and co-workers (reported in SKB report R-10-30) demonstrated that in case of release of radioactivity the near-surface sedimentary system at Forsmark would act as an important geochemical barrier, retarding the transport of reactive radionuclides through a combination of retention processes. In this report the conceptual model of radionuclide transport in the quaternary till at Forsmark has been updated, by considering recent revisions regarding the near-surface lithology. In addition, the impact of important conceptual assumptions made in the model has been evaluated through a series of deterministic and probabilistic (Monte Carlo) sensitivity calculations. The sensitivity study focused on the following effects: 1. Radioactive decay of {sup 135}Cs, {sup 59}Ni, {sup 230}Th and {sup 226}Ra and effects on their transport. 2. Variability in key geochemical parameters, such as the composition of the deep groundwater, availability of sorbing materials in the till, and mineral equilibria. 3. Variability in hydraulic parameters, such as the definition of hydraulic boundaries, and values of hydraulic conductivity, dispersivity and the deep groundwater inflow rate. The overarching conclusion from this study is that the current implementation of the model is robust (the model is largely insensitive to variations in the parameters within the studied ranges) and conservative (the Base Case calculations have a

A Stream Tilling Approach to Surface Area Estimation for Large Scale Spatial Data in a Shared Memory System

Directory of Open Access Journals (Sweden)

Liu Jiping

2017-12-01

Full Text Available Surface area estimation is a widely used tool for resource evaluation in the physical world. When processing large scale spatial data, the input/output (I/O can easily become the bottleneck in parallelizing the algorithm due to the limited physical memory resources and the very slow disk transfer rate. In this paper, we proposed a stream tilling approach to surface area estimation that first decomposed a spatial data set into tiles with topological expansions. With these tiles, the one-to-one mapping relationship between the input and the computing process was broken. Then, we realized a streaming framework towards the scheduling of the I/O processes and computing units. Herein, each computing unit encapsulated a same copy of the estimation algorithm, and multiple asynchronous computing units could work individually in parallel. Finally, the performed experiment demonstrated that our stream tilling estimation can efficiently alleviate the heavy pressures from the I/O-bound work, and the measured speedup after being optimized have greatly outperformed the directly parallel versions in shared memory systems with multi-core processors.

Risk insights from seismic margin reviews

International Nuclear Information System (INIS)

Budnitz, R.J.

1990-01-01

This paper discusses the information that has been derived from the three seismic-margin reviews conducted so far, and the information that is potentially available from using the seismic-margin method more generally. There are two different methodologies for conducting seismic margin reviews of nuclear power plants, one developed under NRC sponsorship and one developed under sponsorship of the Electric Power Research Institute. Both methodologies will be covered in this paper. The paper begins with a summary of the steps necessary to complete a margin review, and will then outline the key technical difficulties that need to be addressed. After this introduction, the paper covers the safety and operational insights derived from the three seismic-margin reviews already completed: the NRC-sponsored review at Maine Yankee; the EPRI-sponsored review at Catawba; and the joint EPRI/NRC/utility effort at Hatch. The emphasis is on engineering insights, with attention to the aspects of the reviews that are easiest to perform and that provide the most readily available insights

Exactly marginal deformations from exceptional generalised geometry

Energy Technology Data Exchange (ETDEWEB)

Ashmore, Anthony [Merton College, University of Oxford,Merton Street, Oxford, OX1 4JD (United Kingdom); Mathematical Institute, University of Oxford,Andrew Wiles Building, Woodstock Road, Oxford, OX2 6GG (United Kingdom); Gabella, Maxime [Institute for Advanced Study,Einstein Drive, Princeton, NJ 08540 (United States); Graña, Mariana [Institut de Physique Théorique, CEA/Saclay,91191 Gif-sur-Yvette (France); Petrini, Michela [Sorbonne Université, UPMC Paris 05, UMR 7589, LPTHE,75005 Paris (France); Waldram, Daniel [Department of Physics, Imperial College London,Prince Consort Road, London, SW7 2AZ (United Kingdom)

2017-01-27

We apply exceptional generalised geometry to the study of exactly marginal deformations of N=1 SCFTs that are dual to generic AdS{sub 5} flux backgrounds in type IIB or eleven-dimensional supergravity. In the gauge theory, marginal deformations are parametrised by the space of chiral primary operators of conformal dimension three, while exactly marginal deformations correspond to quotienting this space by the complexified global symmetry group. We show how the supergravity analysis gives a geometric interpretation of the gauge theory results. The marginal deformations arise from deformations of generalised structures that solve moment maps for the generalised diffeomorphism group and have the correct charge under the generalised Reeb vector, generating the R-symmetry. If this is the only symmetry of the background, all marginal deformations are exactly marginal. If the background possesses extra isometries, there are obstructions that come from fixed points of the moment maps. The exactly marginal deformations are then given by a further quotient by these extra isometries. Our analysis holds for any N=2 AdS{sub 5} flux background. Focussing on the particular case of type IIB Sasaki-Einstein backgrounds we recover the result that marginal deformations correspond to perturbing the solution by three-form flux at first order. In various explicit examples, we show that our expression for the three-form flux matches those in the literature and the obstruction conditions match the one-loop beta functions of the dual SCFT.

RISK-INFORMED SAFETY MARGIN CHARACTERIZATION

International Nuclear Information System (INIS)

Dinh, Nam; Szilard, Ronaldo

2009-01-01

The concept of safety margins has served as a fundamental principle in the design and operation of commercial nuclear power plants (NPPs). Defined as the minimum distance between a system's 'loading' and its 'capacity', plant design and operation is predicated on ensuring an adequate safety margin for safety-significant parameters (e.g., fuel cladding temperature, containment pressure, etc.) is provided over the spectrum of anticipated plant operating, transient and accident conditions. To meet the anticipated challenges associated with extending the operational lifetimes of the current fleet of operating NPPs, the United States Department of Energy (USDOE), the Idaho National Laboratory (INL) and the Electric Power Research Institute (EPRI) have developed a collaboration to conduct coordinated research to identify and address the technological challenges and opportunities that likely would affect the safe and economic operation of the existing NPP fleet over the postulated long-term time horizons. In this paper we describe a framework for developing and implementing a Risk-Informed Safety Margin Characterization (RISMC) approach to evaluate and manage changes in plant safety margins over long time horizons

Solid/liquid partition coefficients (Kd) and plant/soil concentration ratios (CR) for selected soils, tills and sediments at Forsmark

International Nuclear Information System (INIS)

Sheppard, Steve; Sohlenius, Gustav; Omberg, Lars-Gunnar; Borgiel, Mikael; Grolander, Sara; Norden, Sara

2011-11-01

Solid/liquid partition coefficients (K d ) are used to indicate the relative mobility of radionuclides and elements of concern from nuclear fuel waste, as well as from other sources. To indicate the uptake of radionuclides in biota concentration ratios (CR) between soil and biota are used. This report summarized K d data for regolith and marine sediments based on concentrations of 69 indigenous stable elements measured from samples collected at the Forsmark site and CR data concerning cereals growing on these soils. The samples included 50 regolith samples from agricultural land and wetlands, 8 samples of till collected at different depths, and two marine sediment samples. In addition, cereal grains, stems and roots were collected from 4 sites for calculation of CRs. The regolith samples represented the major 5 deposits, which can be used as arable land, at the site (clayey till, glacial clay, clay gyttja and peat (cultivated and undisturbed)). K d values were generally lower for peat compared to clay soils. There were also clear differences in K d resulting from differences in soil chemistry within each regolith type. Soil pH was the most important factor, and K d values for many elements were lower in acidic clay soils compared to basic clay soils. Although there were only a few samples of sandy till and marine sediment, the K d values were generally consistent with the corresponding regolith K d values. Of the different cereal parts the grain always had the lowest CR. In most cases, the root CR was significantly higher than the grain CR, whereas only for a few elements were the grain and stem CR values different

Tectono-Stratigraphy of the Seeps on the Guaymas Basin at the Sonora Margin, Gulf of California, Mexico

Science.gov (United States)

Figueroa Albornoz, L. J.; Mortera-Gutierrez, C. A.; Bandy, W. L.; Escobar-Briones, E. G.; Godfroy, A.; Fouquet, Y.

2013-05-01

, being a sediment source and an erosional mechanism. On the GB stratification, we observe a low angle unconformity given by a transparent acoustical layer. Also, the reflectors at the GB edge and adjacent to GTF structure suggest that the stratification till upward to the scarp. Nevertheless, that GTF scarp represents the eroded paleo-slope of the Sonora Margin, exposing the cutting layers on its facing north slope. The plumes observed near to the Satellite Basin correspond to gas seeps released on the north slope of the scarp of the GTF, where layers of the GB are exposed, and giving the absence of a seal layer. The observed inner plumes in the Satellite Basin probably use the disrupted layers of the facing south scarp of the GTF to release the gas bubbles. The new plume system found off-axis on the Northern Rift has not enough data to explain their origin and release process.

Professional Commitment and Professional Marginalism in Teachers

Directory of Open Access Journals (Sweden)

Kalashnikov A.I.

2017-11-01

Full Text Available The article reviews teachers' attitudes towards the teaching profession which can be expressed both in professional commitment and in professional marginalism. The dominance of professional marginalism could affect destructively the students as well as the teacher’s personality, hence the issues related to the content of personal position of a marginal and the rate of marginalism among teachers. It was suggested that marginalism could be revealed in the study of professional commitment. The study involved 81 teachers of Sverdlovsk secondary schools aged 21—60 years with work experience ranging from 1 month to 39 years. The Professional Commitment Questionnaire was used as the study technique. The results showed that negative emotional attitude towards the profession and reluctance to leave the profession were grouped as a separate factor. The dispersion factor was 12,5%. The factor loadings ranged from 0.42 to 0.84. The study proved that professional marginalism in teachers includes dissatisfaction with work, feelings of resentment against profession and an unwillingness to leave the profession.

A quantitative analysis of transtensional margin width

Science.gov (United States)

Jeanniot, Ludovic; Buiter, Susanne J. H.

2018-06-01

Continental rifted margins show variations between a few hundred to almost a thousand kilometres in their conjugated widths from the relatively undisturbed continent to the oceanic crust. Analogue and numerical modelling results suggest that the conjugated width of rifted margins may have a relationship to their obliquity of divergence, with narrower margins occurring for higher obliquity. We here test this prediction by analysing the obliquity and rift width for 26 segments of transtensional conjugate rifted margins in the Atlantic and Indian Oceans. We use the plate reconstruction software GPlates (http://www.gplates.org) for different plate rotation models to estimate the direction and magnitude of rifting from the initial phases of continental rifting until breakup. Our rift width corresponds to the distance between the onshore maximum topography and the last identified continental crust. We find a weak positive correlation between the obliquity of rifting and rift width. Highly oblique margins are narrower than orthogonal margins, as expected from analogue and numerical models. We find no relationships between rift obliquities and rift duration nor the presence or absence of Large Igneous Provinces (LIPs).

On the evaluation of marginal expected shortfall

DEFF Research Database (Denmark)

Caporin, Massimiliano; Santucci de Magistris, Paolo

2012-01-01

In the analysis of systemic risk, Marginal Expected Shortfall may be considered to evaluate the marginal impact of a single stock on the market Expected Shortfall. These quantities are generally computed using log-returns, in particular when there is also a focus on returns conditional distribution....... In this case, the market log-return is only approximately equal to the weighed sum of equities log-returns. We show that the approximation error is large during turbulent market phases, with a subsequent impact on Marginal Expected Shortfall. We then suggest how to improve the evaluation of Marginal Expected...

[Resection margins in conservative breast cancer surgery].

Science.gov (United States)

Medina Fernández, Francisco Javier; Ayllón Terán, María Dolores; Lombardo Galera, María Sagrario; Rioja Torres, Pilar; Bascuñana Estudillo, Guillermo; Rufián Peña, Sebastián

2013-01-01

Conservative breast cancer surgery is facing a new problem: the potential tumour involvement of resection margins. This eventuality has been closely and negatively associated with disease-free survival. Various factors may influence the likelihood of margins being affected, mostly related to the characteristics of the tumour, patient or surgical technique. In the last decade, many studies have attempted to find predictive factors for margin involvement. However, it is currently the new techniques used in the study of margins and tumour localisation that are significantly reducing reoperations in conservative breast cancer surgery. Copyright © 2012 AEC. Published by Elsevier Espana. All rights reserved.

Anomalous metal concentrations in soil and till at the Ballinalack Zn-Pb deposit, Ireland

Science.gov (United States)

Kalveram, Ann-Kristin; McClenaghan, Seán H.; Kamber, Balz S.

2017-04-01

Metals such as zinc, iron, arsenic and lead are commonly found in low concentrations within soils. These signatures may occur as a result of natural dispersion from metal-bearing geological formations and (or) from anthropogenic sources. Prior to investigating any high or anomalous concentrations of metals in the surficial environment, it is important to reconcile potential sources of metals and verify whether element anomalies are in response to buried mineralization. Here we show how to distinguish true elevated concentrations from naturally occurring variations within a soil system. The research area is situated above the limestone-hosted Ballinalack Zn-Pb deposit in the central Irish Midlands. To investigate the pedogenesis and its related geochemical signature, top of the till and the BC soil horizon were sampled. Although the area can be described as pasture land, it does not preclude previous anthropogenic influences from former agricultural use and local small scale peat harvesting. For the soil BC horizon as well as in the top of the till, aqua regia-digestible element concentrations vary significantly and locally reach anomalous levels: Zn (median: 104 ppm; range: 27 - 13150 ppm), Pb (median: 16 ppm; range: 2 - 6430 ppm), As (median: 7.7 ppm; range: 1.4 - 362 ppm), Ag (median: 0.12 ppm; range: 0.04 - 19.9 ppm), Ba (median: 40 ppm; range: 10 - 1230 ppm), Cd (median: 1.5 ppm; range: 0.2 - 68 ppm), Co (median: 7.3 ppm; range: 0.5 - 22 ppm), Ni (median: 37 ppm; range: 3 - 134 ppm), Fe (median: 17900 ppm; range: 5000 - 52300 ppm), Ga (median: 2.4 ppm; range: 0.3 - 7.6 ppm), Sb (median: 1.2 ppm; range: 0.1 - 197 ppm) and Tl (median: 0.3 ppm; range: 0.02 - 8.6 ppm). Comparison with background levels from the area and grouped according to underlying geology, enrichment factor calculations (against Nb and Zr) indicate an elemental response to metalliferous-bearing bedrock. These results confirm that soil anomalies of Zn, Pb, As, Ag, Ba, Cd, Ni, Sb and Tl, are

Ferritin associates with marginal band microtubules

International Nuclear Information System (INIS)

Infante, Anthony A.; Infante, Dzintra; Chan, M.-C.; How, P.-C.; Kutschera, Waltraud; Linhartova, Irena; Muellner, Ernst W.; Wiche, Gerhard; Propst, Friedrich

2007-01-01

We characterized chicken erythrocyte and human platelet ferritin by biochemical studies and immunofluorescence. Erythrocyte ferritin was found to be a homopolymer of H-ferritin subunits, resistant to proteinase K digestion, heat stable, and contained iron. In mature chicken erythrocytes and human platelets, ferritin was localized at the marginal band, a ring-shaped peripheral microtubule bundle, and displayed properties of bona fide microtubule-associated proteins such as tau. Red blood cell ferritin association with the marginal band was confirmed by temperature-induced disassembly-reassembly of microtubules. During erythrocyte differentiation, ferritin co-localized with coalescing microtubules during marginal band formation. In addition, ferritin was found in the nuclei of mature erythrocytes, but was not detectable in those of bone marrow erythrocyte precursors. These results suggest that ferritin has a function in marginal band formation and possibly in protection of the marginal band from damaging effects of reactive oxygen species by sequestering iron in the mature erythrocyte. Moreover, our data suggest that ferritin and syncolin, a previously identified erythrocyte microtubule-associated protein, are identical. Nuclear ferritin might contribute to transcriptional silencing or, alternatively, constitute a ferritin reservoir

Methylation patterns in marginal zone lymphoma.

Science.gov (United States)

Arribas, Alberto J; Bertoni, Francesco

Promoter DNA methylation is a major regulator of gene expression and transcription. The identification of methylation changes is important for understanding disease pathogenesis, for identifying prognostic markers and can drive novel therapeutic approaches. In this review we summarize the current knowledge regarding DNA methylation in MALT lymphoma, splenic marginal zone lymphoma, nodal marginal zone lymphoma. Despite important differences in the study design for different publications and the existence of a sole large and genome-wide methylation study for splenic marginal zone lymphoma, it is clear that DNA methylation plays an important role in marginal zone lymphomas, in which it contributes to the inactivation of tumor suppressors but also to the expression of genes sustaining tumor cell survival and proliferation. Existing preclinical data provide the rationale to target the methylation machinery in these disorders. Copyright © 2016 Elsevier Ltd. All rights reserved.

Limitations of ''margin'' in qualification tests

International Nuclear Information System (INIS)

Clough, R.L.; Gillen, K.T.

1984-01-01

We have carried out investigations of polymer radiation degradation behaviors which have brought to light a number of reasons why this concept of margin can break down. First of all, we have found that dose-rate effects vary greatly in magnitude. Thus, based on high dose-rate testing, poor materials with large dose-rate effects may be selected over better materials with small effects. Also, in certain cases, material properties have been found to level out (as with PVC) or reverse trend (as with buna-n) at high doses, so that ''margin'' may be ineffective, misleading, or counterproductive. For Viton, the material properties were found to change in opposite directions at high and low dose rates, making ''margin'' inappropriate. The underlying problem with the concept of ''margin'' is that differences in aging conditions can lead to fundamental differences in degradation mechanisms

Silenced, Silence, Silent: Motherhood in the Margins

Science.gov (United States)

Carpenter, Lorelei; Austin, Helena

2007-01-01

This project explores the experiences of women who mother children with ADHD. The authors use the metaphor of the text and the margin. The text is the "motherhood myth" that describes a particular sort of "good" mothering. The margin is the space beyond that text. This marginal space is inhabited by some or all of the mothers they spoke with, some…

Continental transform margins : state of art and future milestones

Science.gov (United States)

Basile, Christophe

2010-05-01

Transform faults were defined 45 years ago as ‘a new class of fault' (Wilson, 1965), and transform margins were consequently individualized as a new class of continental margins. While transform margins represent 20 to 25 % of the total length of continent-ocean transitions, they were poorly studied, especially when compared with the amount of data, interpretations, models and conceptual progress accumulated on divergent or convergent continental margins. The best studied examples of transform margins are located in the northern part of Norway, south of South Africa, in the gulf of California and on both sides of the Equatorial Atlantic. Here is located the Côte d'Ivoire - Ghana margin, where the more complete data set was acquired, based on numerous geological and geophysical cruises, including ODP Leg 159. The first models that encompassed the structure and evolution of transform margins were mainly driven by plate kinematic reconstructions, and evidenced the diachronic end of tectonic activity and the non-cylindrical character of these margins, with a decreasing strike-slip deformation from the convex to the concave divergent-transform intersections. Further thermo-mechanical models were more specifically designed to explain the vertical displacements along transform margins, and especially the occurrence of high-standing marginal ridges. These thermo-mechanical models involved either heat transfer from oceanic to continental lithospheres across the transform faults or tectonically- or gravity-driven mass transfer in the upper crust. These models were far from fully fit observations, and were frequently dedicated to specific example, and not easily generalizable. Future work on transform continental margins may be expected to fill some scientific gaps, and the definition of working directions can benefit from the studies dedicated to other types of margins. At regional scale the structural and sedimentological variability of transform continental margins has

Aspects of marginal expenditures in energy sector

International Nuclear Information System (INIS)

Stojchev, D.; Kynev, K.

1994-01-01

Technical and economical problems of marginal analysis methodology, its application procedure in energy sector and marginal expenditures determination are outlined. A comparative characteristics of the application is made for different periods of time. The differences in calculation of the marginal expenditures and prices are discussed. The operational costs, investments and inflation are analyzed. The mechanism of application of this approach in different planing horizon is outlined. The role of the change in the costs in time, the time unit, volume, the scope of application, etc. are determined. The areas of transition from one to other form of marginal expenditures are shown. 4 refs. (orig.)

Characterizing entanglement with global and marginal entropic measures

International Nuclear Information System (INIS)

Adesso, Gerardo; Illuminati, Fabrizio; De Siena, Silvio

2003-01-01

We qualify the entanglement of arbitrary mixed states of bipartite quantum systems by comparing global and marginal mixednesses quantified by different entropic measures. For systems of two qubits we discriminate the class of maximally entangled states with fixed marginal mixednesses, and determine an analytical upper bound relating the entanglement of formation to the marginal linear entropies. This result partially generalizes to mixed states the quantification of entanglement with marginal mixednesses holding for pure states. We identify a class of entangled states that, for fixed marginals, are globally more mixed than product states when measured by the linear entropy. Such states cannot be discriminated by the majorization criterion

Steel Industry Marginal Opportunity Analysis

Energy Technology Data Exchange (ETDEWEB)

none,

2005-09-01

The Steel Industry Marginal Opportunity Analysis (PDF 347 KB) identifies opportunities for developing advanced technologies and estimates both the necessary funding and the potential payoff. This analysis determines what portion of the energy bandwidth can be captured through the adoption of state-of-the-art technology and practices. R&D opportunities for addressing the remainder of the bandwidth are characterized and plotted on a marginal opportunity curve.

Leaching properties of natural aggregates. Rock materials and tills; Lakegenskaper foer naturballast. Bergmaterial och moraener

Energy Technology Data Exchange (ETDEWEB)

Ekvall, Annika; Bahr, Bo von; Andersson, Tove; Lax, Kaj; Aakesson, Urban [Swedish National Testing and Research Inst., Boraas (Sweden)

2006-02-15

The aim of this project is to produce leaching data for natural aggregates needed for assessment of the environmental impact of alternative materials aimed for use in for example road constructions. Both rock materials and tills are tested. The results shows that very little is leached from natural aggregate. A comparison with landfill criteria for inert waste and the Swedish regulations for drinking water shows that a few samples exceeds the criteria for fluoride ions. All other values are lower then these criteria, and a vast majority of the measurements are below the quantification limit.

Steep microbial boundstone-dominated plaform margins

NARCIS (Netherlands)

Kenter, J.A.M.; Harris, P.M.; Della Porta, G.P.

2005-01-01

Seaward progradation of several kilometers has been documented mostly for leeward margin low-angle carbonate slope systems with a dominant platform top sediment source. However, steep and high-relief margins fronting deep basins can also prograde and as such are somewhat perplexing. Characteristics

The impact of bioaugmentation on dechlorination kinetics and on microbial dechlorinating communities in subsurface clay till

International Nuclear Information System (INIS)

Bælum, Jacob; Scheutz, Charlotte; Chambon, Julie C.; Jensen, Christine Mosegaard; Brochmann, Rikke P.; Dennis, Philip; Laier, Troels; Broholm, Mette M.; Bjerg, Poul L.; Binning, Philip J.; Jacobsen, Carsten S.

2014-01-01

A molecular study on how the abundance of the dechlorinating culture KB-1 affects dechlorination rates in clay till is presented. DNA extracts showed changes in abundance of specific dechlorinators as well as their functional genes. Independently of the KB-1 added, the microbial dechlorinator abundance increased to the same level in all treatments. In the non-bioaugmented microcosms the reductive dehalogenase gene bvcA increased in abundance, but when KB-1 was added the related vcrA gene increased while bvcA genes did not increase. Modeling showed higher vinyl-chloride dechlorination rates and shorter time for complete dechlorination to ethene with higher initial concentration of KB-1 culture, while cis-dichloroethene dechlorination rates were not affected by KB-1 concentrations. This study provides high resolution abundance profiles of Dehalococcoides spp. (DHC) and functional genes, highlights the ecological behavior of KB-1 in clay till, and reinforces the importance of using multiple functional genes as biomarkers for reductive dechlorination. -- Highlights: • vcrA gene is not always linked to reductive dechlorination potential. • High concentrations of KB-1 stimulate vinyl-chloride degradation. • Vinyl-chloride degradation in non-bioaugmented aquifer is linked to bvcA gene. -- vcrA gene biomarker for reductive dechlorination must be supplemented by bvcA and KB-1 had a positive effect on vinyl-chloride dechlorination compared to dichloroethene dechlorination

Variation Trend Analysis of Runoff and Sediment Time Series Based on the R/S Analysis of Simulated Loess Tilled Slopes in the Loess Plateau, China

Directory of Open Access Journals (Sweden)

Ju Zhang

2017-12-01

Full Text Available The objective of this study was to illustrate the temporal variation of runoff and sediment of loess tilled slopes under successive rainfall conditions. Loess tilled slopes with four microtopography types (straight cultivated slope, artificial backhoe, artificial digging, and contour tillage under five slope gradients (5°, 10°, 15°, 20°, 25° were simulated and a rainfall intensity of 60 mm/h was adopted. The temporal trends of runoff and sediment yield were predicted based on the Rescaled Range (R/S analysis method. The results indicate that the Hurst indices of runoff time series and sediment time series are higher than 0.5, and a long-term positive correlation exists between the future and the past. This means that runoff and sediment of loess tilled slopes in the future will have the same trends as in the past. The results obtained by the classical R/S analysis method were the same as those of the modified R/S analysis method. The rationality and reliability of the R/S analysis method were further identified and the method can be used for predicting the trend of runoff and sediment yield. The correlation between the microtopography and the Hurst indices of the runoff and sediment yield time series, as well as between the slopes and the Hurst indices, were tested, and the result was that there was no significant correlation between them. The microtopography and slopes cannot affect the correlation and continuity of runoff and sediment yield time series. This study provides an effective method for predicting variations in the trends of runoff and sediment yield on loess tilled slopes.

Conference Report: The New Discovery of Margins: Theory-Based Excursions in Marginal Social Fields

OpenAIRE

Kirchner, Babette; Lorenzen, Jule-Marie; Striffler, Christine

2014-01-01

At this year's spring conference of the Sociology of Knowledge Section of the German Sociological Association, a diverse range of theoretical concepts and multiple empirical insights into different marginal social fields were presented. As in everyday life, drawing a line between center and margin can be seen as an important challenge that must equally be faced in sociology. The socially constructed borderline appears to be highly variable. Therefore it has to be delineated or fixed somehow. ...

Evaluating the marginal utility principle for long-term hydropower scheduling

International Nuclear Information System (INIS)

Zhao, Tongtiegang; Zhao, Jianshi; Liu, Pan; Lei, Xiaohui

2015-01-01

Highlights: • Analysis of one-, two- and multi-period hydropower scheduling. • Derivation of marginal cost and marginal return of carry-over storage. • Evaluation of the marginal utility principle in a case study of the Three Gorges Reservoir. - Abstract: The conversion of the potential energy of dammed water into hydropower depends on both reservoir storage and release, which are the major difficulties in hydropower reservoir operation. This study evaluates the marginal utility principle, which determines the optimal carry-over storage between periods, for long-term hydropower scheduling. Increasing marginal cost and decreasing marginal return are two important characteristics that determine the marginal utility principle in water supply. However, the notion of decreasing marginal return is inapplicable in hydropower scheduling. Instead, the carry-over storage from one period has an increasing marginal contribution to the power generation in the next period. Although carry-over storage incurs an increasing marginal cost to the power generation in the current period, the marginal return is higher than the marginal cost. The marginal return from the carry-over storage further increases in the multi-period case. These findings suggest saving as much carry-over storage as possible, which is bounded by the operational constraints of storage capacity, environmental flow, and installed capacity in actual hydropower scheduling. The marginal utility principle is evaluated for a case study of the Three Gorges Reservoir, and the effects of the constraints are discussed. Results confirm the theoretical findings and show that the marginal return from carry-over storage is larger than the marginal cost. The operational constraints help determine the optimal carry-over storage.

From Borders to Margins

DEFF Research Database (Denmark)

Parker, Noel

2009-01-01

of entities that are ever open to identity shifts.  The concept of the margin possesses a much wider reach than borders, and focuses continual attention on the meetings and interactions between a range of indeterminate entities whose interactions may determine both themselves and the types of entity...... upon Deleuze's philosophy to set out an ontology in which the continual reformulation of entities in play in ‘post-international' society can be grasped.  This entails a strategic shift from speaking about the ‘borders' between sovereign states to referring instead to the ‘margins' between a plethora...

Mental Depreciation and Marginal Decision Making

Science.gov (United States)

Heath; Fennema

1996-11-01

We propose that individuals practice "mental depreciation," that is, they implicitly spread the fixed costs of their expenses over time or use. Two studies explore how people spread fixed costs on durable goods. A third study shows that depreciation can lead to two distinct errors in marginal decisions: First, people sometimes invest too much effort to get their money's worth from an expense (e.g., they may use a product a lot to spread the fixed expense across more uses). Second, people sometimes invest too little effort to get their money's worth: When people add a portion of the fixed cost to the current costs, their perceived marginal (i.e., incremental) costs exceed their true marginal costs. In response, they may stop investing because their perceived costs surpass the marginal benefits they are receiving. The latter effect is supported by two field studies that explore real board plan decisions by university students.

Marginal and Interaction Effects in Ordered Response Models

OpenAIRE

Debdulal Mallick

2009-01-01

In discrete choice models the marginal effect of a variable of interest that is interacted with another variable differs from the marginal effect of a variable that is not interacted with any variable. The magnitude of the interaction effect is also not equal to the marginal effect of the interaction term. I present consistent estimators of both marginal and interaction effects in ordered response models. This procedure is general and can easily be extended to other discrete choice models. I ...

CRBRP structural and thermal margin beyond the design base

International Nuclear Information System (INIS)

Strawbridge, L.E.

1979-01-01

Prudent margins beyond the design base have been included in the design of Clinch River Breeder Reactor Plant to further reduce the risk to the public from highly improbable occurrences. These margins include Structural Margin Beyond the Design Base to address the energetics aspects and Thermal Margin Beyond the Design Base to address the longer term thermal and radiological consequences. The assessments that led to the specification of these margins are described, along with the experimental support for those assessments. 8 refs

Positive Surgical Margins in Favorable-Stage Differentiated Thyroid Cancer.

Science.gov (United States)

Mercado, Catherine E; Drew, Peter A; Morris, Christopher G; Dziegielewski, Peter T; Mendenhall, William M; Amdur, Robert J

2018-04-16

The significance of positive margin in favorable-stage well-differentiated thyroid cancer is controversial. We report outcomes of positive-margin patients with a matched-pair comparison to a negative-margin group. A total of 25 patients with classic-histology papillary or follicular carcinoma, total thyroidectomy +/- node dissection, stage T1-3N0-1bM0, positive surgical margin at primary site, adjuvant radioactive iodine (I-131), and age older than 18 years were treated between 2003 and 2013. Endpoints were clinical and biochemical (thyroglobulin-only) recurrence-free survival. Matched-pair analysis involved a 1:1 match with negative-margin cases matched for overall stage and I-131 dose. Recurrence-free survival in positive-margin patients was 71% at 10 years. No patient was successfully salvaged with additional treatment. Only 1 patient died of thyroid cancer. Recurrence-free survival at 10 years was worse with a positive (71%) versus negative (90%) margin (P=0.140). Cure with a microscopically positive margin was suboptimal (71%) despite patients having classic-histology papillary and follicular carcinoma, favorable stage, and moderate-dose I-131 therapy.

Learning Convex Inference of Marginals

OpenAIRE

Domke, Justin

2012-01-01

Graphical models trained using maximum likelihood are a common tool for probabilistic inference of marginal distributions. However, this approach suffers difficulties when either the inference process or the model is approximate. In this paper, the inference process is first defined to be the minimization of a convex function, inspired by free energy approximations. Learning is then done directly in terms of the performance of the inference process at univariate marginal prediction. The main ...

Simulating the impact of no-till systems on field water fluxes and maize productivity under semi-arid conditions

Science.gov (United States)

Mupangwa, W.; Jewitt, G. P. W.

Crop output from the smallholder farming sector in sub-Saharan Africa is trailing population growth leading to widespread household food insecurity. It is therefore imperative that crop production in semi-arid areas be improved in order to meet the food demand of the ever increasing human population. No-till farming practices have the potential to increase crop productivity in smallholder production systems of sub-Saharan Africa, but rarely do because of the constraints experienced by these farmers. One of the most significant of these is the consumption of mulch by livestock. In the absence of long term on-farm assessment of the no-till system under smallholder conditions, simulation modelling is a tool that provides an insight into the potential benefits and can highlight shortcomings of the system under existing soil, climatic and socio-economic conditions. Thus, this study was designed to better understand the long term impact of no-till system without mulch cover on field water fluxes and maize productivity under a highly variable rainfall pattern typical of semi-arid South Africa. The simulated on-farm experiment consisted of two tillage treatments namely oxen-drawn conventional ploughing (CT) and ripping (NT). The APSIM model was applied for a 95 year period after first being calibrated and validated using measured runoff and maize yield data. The predicted results showed significantly higher surface runoff from the conventional system compared to the no-till system. Predicted deep drainage losses were higher from the NT system compared to the CT system regardless of the rainfall pattern. However, the APSIM model predicted 62% of the annual rainfall being lost through soil evaporation from both tillage systems. The predicted yields from the two systems were within 50 kg ha -1 difference in 74% of the years used in the simulation. In only 9% of the years, the model predicted higher grain yield in the NT system compared to the CT system. It is suggested that

Spectrum estimation method based on marginal spectrum

International Nuclear Information System (INIS)

Cai Jianhua; Hu Weiwen; Wang Xianchun

2011-01-01

FFT method can not meet the basic requirements of power spectrum for non-stationary signal and short signal. A new spectrum estimation method based on marginal spectrum from Hilbert-Huang transform (HHT) was proposed. The procession of obtaining marginal spectrum in HHT method was given and the linear property of marginal spectrum was demonstrated. Compared with the FFT method, the physical meaning and the frequency resolution of marginal spectrum were further analyzed. Then the Hilbert spectrum estimation algorithm was discussed in detail, and the simulation results were given at last. The theory and simulation shows that under the condition of short data signal and non-stationary signal, the frequency resolution and estimation precision of HHT method is better than that of FFT method. (authors)

[Summarizing of medicinal alerts in Ivory Coast from 2001 till 2010].

Science.gov (United States)

N'Guessan-Irié, Amenan Geneviève; Yavo, Jean-Claude; Guillaume Amari, Antoine Serge; Yapi, Ange Désiré

2012-01-01

STUDY'S AIM: This study aims a more efficient follow-up of the safety of medicines with human usage on the Ivory Coast territory. The structure responsible for pharmacovigilance in Ivory Coast i.e. DPM listed the medicinal alerts from 2001 till 2010. It emerges 237 medicinal alerts among which 145 stops of marketing, 55 withdrawals of lots, 33 information notes and 4 levying of suspension of medicines. These alerts result mainly from pharmaceutical companies (49%) and the French Drug Agency or ANSM (ex-Afssaps) (43%). They mainly concern drugs of infectious target (22%) and pneumology (18%) and their motivations are so much industrial with mainly commercial reasons (27%) as of pharmacovigilance dominated by unfavorable profit/risk connections. These results constitute an important database for the survey of the medicines market in Ivory Coast and an additional motivation to accelerate the implementation of a real national center of pharmacovigilance. © 2012 Société Française de Pharmacologie et de Thérapeutique.

Integrated weed management systems with herbicide-tolerant crops in the European Union: lessons learnt from home and abroad.

Science.gov (United States)

Lamichhane, Jay Ram; Devos, Yann; Beckie, Hugh J; Owen, Micheal D K; Tillie, Pascal; Messéan, Antoine; Kudsk, Per

2017-06-01

Conventionally bred (CHT) and genetically modified herbicide-tolerant (GMHT) crops have changed weed management practices and made an important contribution to the global production of some commodity crops. However, a concern is that farm management practices associated with the cultivation of herbicide-tolerant (HT) crops further deplete farmland biodiversity and accelerate the evolution of herbicide-resistant (HR) weeds. Diversification in crop systems and weed management practices can enhance farmland biodiversity, and reduce the risk of weeds evolving herbicide resistance. Therefore, HT crops are most effective and sustainable as a component of an integrated weed management (IWM) system. IWM advocates the use of multiple effective strategies or tactics to manage weed populations in a manner that is economically and environmentally sound. In practice, however, the potential benefits of IWM with HT crops are seldom realized because a wide range of technical and socio-economic factors hamper the transition to IWM. Here, we discuss the major factors that limit the integration of HT crops and their associated farm management practices in IWM systems. Based on the experience gained in countries where CHT or GMHT crops are widely grown and the increased familiarity with their management, we propose five actions to facilitate the integration of HT crops in IWM systems within the European Union.

Thermal margin model for transition core of KSNP

International Nuclear Information System (INIS)

Nahm, Kee Yil; Lim, Jong Seon; Park, Sung Kew; Chun, Chong Kuk; Hwang, Sun Tack

2004-01-01

The PLUS7 fuel was developed with mixing vane grids for KSNP. For the transition core partly loaded with the PLUS7 fuels, the procedure to set up the optimum thermal margin model of the transition core was suggested by introducing AOPM concept into the screening method which determines the limiting assembly. According to the procedure, the optimum thermal margin model of the first transition core was set up by using a part of nuclear data for the first transition and the homogeneous core with PLUS7 fuels. The generic thermal margin model of PLUS7 fuel was generated with the AOPM of 138%. The overpower penalties on the first transition core were calculated to be 1.0 and 0.98 on the limiting assembly and the generic thermal margin model, respectively. It is not usual case to impose the overpower penalty on reload cores. It is considered that the lack of channel flow due to the difference of pressure drop between PLUS7 and STD fuels results in the decrease of DNBR. The AOPM of the first transition core is evaluated to be about 135% by using the optimum generic thermal margin model which involves the generic thermal margin model and the total overpower penalty. The STD fuel is not included among limiting assembly candidates in the second transition core, because they have much lower pin power than PLUS7 fuels. The reduced number of STD fuels near the limiting assembly candidates the flow from the limiting assembly to increase the thermal margin for the second transition core. It is expected that cycle specific overpower penalties increase the thermal margin for the transition core. Using the procedure to set up the optimum thermal margin model makes sure that the enhanced thermal margin of PLUS7 fuel can be sufficiently applied to not only the homogeneous core but also the transition core

Flow and transport processes in a macroporous subsurface-drained glacial till soil

DEFF Research Database (Denmark)

Villholth, Karen G.; Jensen, Karsten Høgh

1998-01-01

disturbance and compaction of the soil surface. Hypothetically introducing fully surface-connected macropores into the calibrated model resulted in a 22% increase in the loss of solute to the drain, indicating the significance of the hydraulic conditions at the soil surface and the model specification thereof......The experimental results from a field-scale tracer experiment in a subsurface-drained glacial till soil were analyzed by the application of a single/dual porosity model (MACRO), optionally accounting for concurrent and interacting flow and transport in the bulk soil porosity as well...... concentration. The exchange was overpredicted and too rapid when the soil aggregate size (distance between macropores) obtained from an image analysis of soil cores was used in the model. On this basis, the model assumption of instant equilibration of the solute across the matrix porosity, disregarding small...

Reconstructing Rodinia by Fitting Neoproterozoic Continental Margins

Science.gov (United States)

Stewart, John H.

2009-01-01

Reconstructions of Phanerozoic tectonic plates can be closely constrained by lithologic correlations across conjugate margins by paleontologic information, by correlation of orogenic belts, by paleomagnetic location of continents, and by ocean floor magmatic stripes. In contrast, Proterozoic reconstructions are hindered by the lack of some of these tools or the lack of their precision. To overcome some of these difficulties, this report focuses on a different method of reconstruction, namely the use of the shape of continents to assemble the supercontinent of Rodinia, much like a jigsaw puzzle. Compared to the vast amount of information available for Phanerozoic systems, such a limited approach for Proterozoic rocks, may seem suspect. However, using the assembly of the southern continents (South America, Africa, India, Arabia, Antarctica, and Australia) as an example, a very tight fit of the continents is apparent and illustrates the power of the jigsaw puzzle method. This report focuses on Neoproterozoic rocks, which are shown on two new detailed geologic maps that constitute the backbone of the study. The report also describes the Neoproterozoic, but younger or older rocks are not discussed or not discussed in detail. The Neoproterozoic continents and continental margins are identified based on the distribution of continental-margin sedimentary and magmatic rocks that define the break-up margins of Rodinia. These Neoproterozoic continental exposures, as well as critical Neo- and Meso-Neoproterozoic tectonic features shown on the two new map compilations, are used to reconstruct the Mesoproterozoic supercontinent of Rodinia. This approach differs from the common approach of using fold belts to define structural features deemed important in the Rodinian reconstruction. Fold belts are difficult to date, and many are significantly younger than the time frame considered here (1,200 to 850 Ma). Identifying Neoproterozoic continental margins, which are primarily

Margins for treatment planning of proton therapy

International Nuclear Information System (INIS)

Thomas, Simon J

2006-01-01

For protons and other charged particles, the effect of set-up errors on the position of isodoses is considerably less in the direction of the incident beam than it is laterally. Therefore, the margins required between the clinical target volume (CTV) and planning target volume (PTV) can be less in the direction of the incident beam than laterally. Margins have been calculated for a typical head plan and a typical prostate plan, for a single field, a parallel opposed and a four-field arrangement of protons, and compared with margins calculated for photons, assuming identical geometrical uncertainties for each modality. In the head plan, where internal motion was assumed negligible, the CTV-PTV margin reduced from approximately 10 mm to 3 mm in the axial direction for the single field and parallel opposed plans. For a prostate plan, where internal motion cannot be ignored, the corresponding reduction in margin was from 11 mm to 7 mm. The planning organ at risk (PRV) margin in the axial direction reduced from 6 mm to 2 mm for the head plan, and from 7 mm to 4 mm for the prostate plan. No reduction was seen on the other axes, or for any axis of the four-field plans. Owing to the shape of proton dose distributions, there are many clinical cases in which good dose distributions can be obtained with one or two fields. When this is done, it is possible to use smaller PTV and PRV margins. This has the potential to convert untreatable cases, in which the PTV and PRV overlap, into cases with a gap between PTV and PRV of adequate size for treatment planning

Margins in breast conserving surgery: The financial cost & potential savings associated with the new margin guidelines.

Science.gov (United States)

Singer, Lauren; Brown, Eric; Lanni, Thomas

2016-08-01

In this study, we compare the indications for re-excision, the findings of additional tumor in the re-excision specimen as they relate to margin status, and costs associated with re-excision based on recent new consensus statements. A retrospective analysis was performed on 462 patients with invasive breast carcinoma who underwent at least one lumpectomy between January 2011 and December 2013. Postoperative data was analyzed based on where additional disease was found, as it relates to the margin status of the initial lumpectomy and the additional direct costs associated with additional procedures. Of the 462 patients sampled, 149 underwent a re-excision surgery (32.2%). Four patients underwent mastectomy as their second operation. In the 40 patients with additional disease found on re-excision, 36 (90.0%) of them had a positive margin on their initial lumpectomy. None of the four mastectomy patients had residual disease. The mean cost of the initial lumpectomy for all 462 patients was $2118.01 plus an additional $1801.92 for those who underwent re-excision. A positive margin was most predictive of finding residual tumor on re-excision as would be expected. Using old criteria only 0.07% (4/61) of patients who had undergone re-excision with a 'clear' margin, had additional tumor found, at a total cost of $106,354.11. Thus, the new consensus guidelines will lead to less overall cost, at no clinical risk to patients while reducing a patient's surgical risk and essentially eliminating delays in adjuvant care. Copyright © 2016 Elsevier Ltd. All rights reserved.

Plasticity margin recovery during annealing after cold deformation

International Nuclear Information System (INIS)

Bogatov, A.A.; Smirnov, S.V.; Kolmogorov, V.L.

1978-01-01

Restoration of the plasticity margin in steel 20 after cold deformation and annealing at 550 - 750 C and soaking for 5 - 300 min was investigated. The conditions of cold deformation under which the metal acquires microdefects unhealed by subsequent annealing were determined. It was established that if the degree of utilization of the plasticity margin is psi < 0.5, the plasticity margin in steel 20 can be completely restored by annealing. A mathematical model of restoration of the plasticity margin by annealing after cold deformation was constructed. A statistical analysis showed good agreement between model and experiment

Subsurface phosphorus transport through a no-till field in the semi arid Palouse region

Science.gov (United States)

Norby, J. C.; Brooks, E. S.; Strawn, D. G.

2017-12-01

Excess application of fertilizers containing nitrogen and phosphorus for farming use has led to ongoing water quality issues in the United States. When these nutrients leave agronomic systems, and enter water bodies in large quantities, algal bloom and eutrophication can occur. Extensive studies focusing on phosphorus as a pollutant from agronomic systems have been conducted in the many regions of the United States; however, there has been a lack of studies completed in the semiarid Palouse region of eastern Washington and western Idaho. The goal of this research study was to better understand how no-till farm management has altered soil P temporally and the current availability for off-site transport of P throughout an artificially drained catchment at the Cook Agronomy Farm in Pullman, WA. We also attempted to determine the processes responsible for subsurface flow of phosphorus, specifically through preferential flow pathways. Dissolved reactive P (DRP)concentrations of subsurface drainage from a artificial drain exceeded TMDL threshold concentrations during numerous seasonal high flow events over the two-year study time frame. Soil analyses show a highly variable distribution of water-extractable P across the sub-catchment area and initial results suggest a translocation of P species deeper into the soil profile after implementing no-till practices in 1998. We hypothesized that a greater network of macropores from lack of soil disturbance allow for preferential flow of nutrient-laden water deeper into the subsurface and to the artificial drain system. Simulated flow experiments on soil cores from the study site showed large-scale macropore development, extreme variability in soil conductivity, and high P adsorption potential for the soils, suggesting a disconnect between P movement through macropore soil and subsurface drainage water rich in DRP at the artificial drain line outlet.

Availability of Micro-Tom mutant library combined with TILLING in molecular breeding of tomato fruit shelf-life.

Science.gov (United States)

Okabe, Yoshihiro; Asamizu, Erika; Ariizumi, Tohru; Shirasawa, Kenta; Tabata, Satoshi; Ezura, Hiroshi

2012-06-01

Novel mutant alleles of an ethylene receptor Solanum lycopersicum ETHYLENE RESPONSE1 (SlETR1) gene, Sletr1-1 and Sletr1-2, were isolated from the Micro-Tom mutant library by TILLING in our previous study. They displayed different levels of impaired fruit ripening phenotype, suggesting that these alleles could be a valuable breeding material for improving shelf life of tomato fruit. To conduct practical use of the Sletr1 alleles in tomato breeding, genetic complementation analysis by transformation of genes carrying each allele is required. In this study, we generated and characterized transgenic lines over-expressing Sletr1-1 and Sletr1-2. All transgenic lines displayed ethylene insensitive phenotype and ripening inhibition, indicating that Sletr1-1 and Sletr1-2 associate with the ethylene insensitive phenotype. The level of ethylene sensitivity in the seedling was different between Sletr1-1 and Sletr1-2 transgenic lines, whereas no apparent difference was observed in fruit ripening phenotype. These results suggested that it is difficult to fine-tune the extent of ripening by transgenic approach even if the weaker allele (Sletr1-2) was used. Our present and previous studies indicate that the Micro-Tom mutant library combined with TILLING could be an efficient tool for exploring genetic variations of important agronomic traits in tomato breeding.

Availability of Micro-Tom mutant library combined with TILLING in molecular breeding of tomato fruit shelf-life

Science.gov (United States)

Okabe, Yoshihiro; Asamizu, Erika; Ariizumi, Tohru; Shirasawa, Kenta; Tabata, Satoshi; Ezura, Hiroshi

2012-01-01

Novel mutant alleles of an ethylene receptor Solanum lycopersicum ETHYLENE RESPONSE1 (SlETR1) gene, Sletr1-1 and Sletr1-2, were isolated from the Micro-Tom mutant library by TILLING in our previous study. They displayed different levels of impaired fruit ripening phenotype, suggesting that these alleles could be a valuable breeding material for improving shelf life of tomato fruit. To conduct practical use of the Sletr1 alleles in tomato breeding, genetic complementation analysis by transformation of genes carrying each allele is required. In this study, we generated and characterized transgenic lines over-expressing Sletr1-1 and Sletr1-2. All transgenic lines displayed ethylene insensitive phenotype and ripening inhibition, indicating that Sletr1-1 and Sletr1-2 associate with the ethylene insensitive phenotype. The level of ethylene sensitivity in the seedling was different between Sletr1-1 and Sletr1-2 transgenic lines, whereas no apparent difference was observed in fruit ripening phenotype. These results suggested that it is difficult to fine-tune the extent of ripening by transgenic approach even if the weaker allele (Sletr1-2) was used. Our present and previous studies indicate that the Micro-Tom mutant library combined with TILLING could be an efficient tool for exploring genetic variations of important agronomic traits in tomato breeding. PMID:23136532

Reinforcing marginality? Maternal health interventions in rural Nicaragua.

Science.gov (United States)

Kvernflaten, Birgit

2017-06-23

To achieve Millennium Development Goal 5 on maternal health, many countries have focused on marginalized women who lack access to care. Promoting facility-based deliveries to ensure skilled birth attendance and emergency obstetric care has become a main measure for preventing maternal deaths, so women who opt for home births are often considered 'marginal' and in need of targeted intervention. Drawing upon ethnographic data from Nicaragua, this paper critically examines the concept of marginality in the context of official efforts to increase institutional delivery amongst the rural poor, and discusses lack of access to health services among women living in peripheral areas as a process of marginalization. The promotion of facility birth as the new norm, in turn, generates a process of 're-marginalization', whereby public health officials morally disapprove of women who give birth at home, viewing them as non-compliers and a problem to the system. In rural Nicaragua, there is a discrepancy between the public health norm and women's own preferences and desires for home birth. These women live at the margins also in spatial and societal terms, and must relate to a health system they find incapable of providing good, appropriate care. Strong public pressure for institutional delivery makes them feel distressed and pressured. Paradoxically then, the aim of including marginal groups in maternal health programmes engenders resistance to facility birth.

Exploring economically and environmentally viable northeastern US dairy farm strategies for coping with rising corn grain prices.

Science.gov (United States)

Ghebremichael, L T; Veith, T L; Cerosaletti, P E; Dewing, D E; Rotz, C A

2009-08-01

In 2008, corn grain prices rose $115/t of DM above the 2005 average. Such an increase creates tight marginal profits for small (profit losses by growing more corn silage and reducing corn grain purchases. This study applies the Integrated Farm Systems Model to 1 small and 1 medium-sized New York State dairy farm to predict 1) sediment and P loss impacts from expanding corn fields, 2) benefits of no-till or cover cropping on corn fields, and 3) alternatives to the economic challenge of the current farming system as the price ratio of milk to corn grain continues to decline. Based on the simulation results, expanding corn silage production by 3% of the cultivated farm area increased sediment and sediment-bound P losses by 41 and 18%, respectively. Implementing no-till controlled about 84% of the erosion and about 75% of the sediment-bound P that would have occurred from the conventionally tilled, expanded corn production scenario. Implementing a conventionally tilled cover crop with the conventionally tilled, expanded corn production scenario controlled both erosion and sediment-bound P, but to a lesser extent than no-till corn with no cover crop. However, annual farm net return using cover crops was slightly less than when using no-till. Increasing on-farm grass productivity while feeding cows a high-quality, high-forage diet and precise dietary P levels offered dual benefits: 1) improved farm profitability from reduced purchases of dietary protein and P supplements, and 2) decreased runoff P losses from reduced P-levels in applied manure. Moreover, alternatives such as growing additional small grains on marginal lands and increasing milk production levels demonstrated great potential in increasing farm profitability. Overall, it is crucial that conservation measures such as no-till and cover cropping be implemented on new or existing corn lands as these areas often pose the highest threat for P losses through runoff. Although alternatives that would likely provide

Effect of posterior crown margin placement on gingival health.

Science.gov (United States)

Reitemeier, Bernd; Hänsel, Kristina; Walter, Michael H; Kastner, Christian; Toutenburg, Helge

2002-02-01

The clinical impact of posterior crown margin placement on gingival health has not been thoroughly quantified. This study evaluated the effect of posterior crown margin placement with multivariate analysis. Ten general dentists reviewed 240 patients with 480 metal-ceramic crowns in a prospective clinical trial. The alloy was randomly selected from 2 high gold, 1 low gold, and 1 palladium alloy. Variables were the alloy used, oral hygiene index score before treatment, location of crown margins at baseline, and plaque index and sulcus bleeding index scores recorded for restored and control teeth after 1 year. The effect of crown margin placement on sulcular bleeding and plaque accumulation was analyzed with regression models (Prisk of bleeding at intrasulcular posterior crown margins was approximately twice that at supragingival margins. Poor oral hygiene before treatment and plaque also were associated with sulcular bleeding. Facial sites exhibited a lower probability of sulcular bleeding than lingual surfaces. Type of alloy did not influence sulcular bleeding. In this study, placement of crown margins was one of several parameters that affected gingival health.

Colorado Basin Structure and Rifting, Argentine passive margin

Science.gov (United States)

Autin, Julia; Scheck-Wenderoth, Magdalena; Loegering, Markus; Anka, Zahie; Vallejo, Eduardo; Rodriguez, Jorge; Marchal, Denis; Reichert, Christian; di Primio, Rolando

2010-05-01

The Argentine margin presents a strong segmentation with considerable strike-slip movements along the fracture zones. We focus on the volcanic segment (between the Salado and Colorado transfer zones), which is characterized by seaward dipping reflectors (SDR) all along the ocean-continent transition [e.g. Franke et al., 2006; Gladczenko et al., 1997; Hinz et al., 1999]. The segment is structured by E-W trending basins, which differs from the South African margin basins and cannot be explained by classical models of rifting. Thus the study of the relationship between the basins and the Argentine margin itself will allow the understanding of their contemporary development. Moreover the comparison of the conjugate margins suggests a particular evolution of rifting and break-up. We firstly focus on the Colorado Basin, which is thought to be the conjugate of the well studied Orange Basin [Hirsch et al., 2009] at the South African margin [e.g. Franke et al., 2006]. This work presents results of a combined approach using seismic interpretation and structural, isostatic and thermal modelling highlighting the structure of the crust. The seismic interpretation shows two rift-related discordances: one intra syn-rift and the break-up unconformity. The overlying sediments of the sag phase are less deformed (no sedimentary wedges) and accumulated before the generation of oceanic crust. The axis of the Colorado Basin trends E-W in the western part, where the deepest pre-rift series are preserved. In contrast, the basin axis turns to a NW-SE direction in its eastern part, where mainly post-rift sediments accumulated. The most distal part reaches the margin slope and opens into the oceanic basin. The general basin direction is almost orthogonal to the present-day margin trend. The most frequent hypothesis explaining this geometry is that the Colorado Basin is an aborted rift resulting from a previous RRR triple junction [e.g. Franke et al., 2002]. The structural interpretation

The Seismicity of Two Hyperextended Margins

Science.gov (United States)

Redfield, Tim; Terje Osmundsen, Per

2013-04-01

A seismic belt marks the outermost edge of Scandinavia's proximal margin, inboard of and roughly parallel to the Taper Break. A similar near- to onshore seismic belt runs along its inner edge, roughly parallel to and outboard of the asymmetric, seaward-facing escarpment. The belts converge at both the northern and southern ends of Scandinavia, where crustal taper is sharp and the proximal margin is narrow. Very few seismic events have been recorded on the intervening, gently-tapering Trøndelag Platform. Norway's distribution of seismicity is systematically ordered with respect to 1) the structural templates of high-beta extension that shaped the thinning gradient during Late Jurassic or Early Cretaceous time, and 2) the topographically resurgent Cretaceous-Cenozoic "accommodation phase" family of escarpments that approximate the innermost limit of crustal thinning [See Redfield and Osmundsen (2012) for diagrams, definitions, discussion, and supporting citations.] Landwards from the belt of earthquake epicenters that mark the Taper Break the crust consistently thickens, and large fault arrays tend to sole out at mid crustal levels. Towards the sea the crystalline continental crust is hyperextended, pervasively faulted, and generally very thin. Also, faulting and serpentinization may have affected the uppermost parts of the distal margin's lithospheric mantle. Such contrasting structural conditions may generate a contrasting stiffness: for a given stress, more strain can be accommodated in the distal margin than in the less faulted proximal margin. By way of comparison, inboard of the Taper Break on the gently-tapered Trøndelag Platform, faulting was not penetrative. There, similar structural conditions prevail and proximal margin seismicity is negligible. Because stress concentration can occur where material properties undergo significant contrast, the necking zone may constitute a natural localization point for post-thinning phase earthquakes. In Scandinavia

The Marginal Source of Finance

OpenAIRE

Lindhe, Tobias

2002-01-01

This paper addresses the ongoingdebate on which view of equity, traditional or new, that best describes firm behavior. According to the traditional view, the marginal source of finance is new equity, whereas under to the new view, marginal financing comes from retained earnings. In the theoretical part, we set up a model where the firm faces a cost of adjusting the dividend level because of an aggravated free cash flow problem. The existence of such a cost - which has been used in arguing the...

‍Correlation between the scores of dental students in theory and practical restoration courses from 1991 till 2012

OpenAIRE

A. R. Danesh kazemi; A. R. Davari; M. Momeni Sarvestani

2013-01-01

Introduction: In order to codify a better curriculum and develop the quality of education, continuous monitoring dental students' education during their study is necessary. This study was conducted on the course scores of dental students of Shahid Sadoughi University of Medical Sciences from 1991 till 2012 on the theory and practical restoration courses. The correlation between these scores was investigated. Methods: This was a cross-sectional study which was performed retrospectively on all ...

Ridge sowing of sunflower (Helianthus annuus L.) in a minimum till system improves the productivity, oil quality, and profitability on a sandy loam soil under an arid climate.

Science.gov (United States)

Sher, Ahmad; Suleman, Muhammad; Qayyum, Abdul; Sattar, Abdul; Wasaya, Allah; Ijaz, Muhammad; Nawaz, Ahmad

2018-04-01

Sunflower (Helianthus annuus L.) is a major oilseed crop grown for its edible oil across the globe including Pakistan. In Pakistan, the production of edible oil is less than the required quantity; the situation is being worsened with the increasing population. Thus, there is dire need to grow those sunflower genotypes which perform better under a given set of agronomic practices. In this 2-year study, we compared four sunflower genotypes, viz., Armoni, Kundi, Sinji, and S-278 for their yield potential, oil contents, fatty acid composition, and profitability under three sowing methods, viz., bed sowing, line sowing, and ridge sowing and two tillage system, viz., plow till and minimum till. Among the sunflower genotypes, the genotype Armoni produced the highest plant height, number of leaves, head diameter, 1000-achene weight, and achene yield; the oil contents and oleic acid were the highest in genotype Sinji. Among the sowing methods, the highest number of leaves per plant, head diameter, number of achenes per head, achene yield, and oil contents were recorded in ridge sowing. Among the tillage systems, the highest head diameter 16. 2 cm, 1000-achene weight (57.2 g), achene yield (1.8 t ha -1 ), oil contents (35.2%), and oleic acid (15.2%) were recorded in minimum till sunflower. The highest net benefits and benefit to cost ratio were recorded in minimum till ridge sown Armoni genotype. In conclusion, the genotype Armoni should be grown on ridges to achieve the highest achene yield, oil contents, and net profitability.

On probabilistically defined margins in radiation therapy

Energy Technology Data Exchange (ETDEWEB)

Papiez, Lech; Langer, Mark [Department of Radiation Oncology, Indiana University, Indianapolis, IN (United States)

2006-08-21

Margins about a target volume subject to external beam radiation therapy are designed to assure that the target volume of tissue to be sterilized by treatment is adequately covered by a lethal dose. Thus, margins are meant to guarantee that all potential variation in tumour position relative to beams allows the tumour to stay within the margin. Variation in tumour position can be broken into two types of dislocations, reducible and irreducible. Reducible variations in tumour position are those that can be accommodated with the use of modern image-guided techniques that derive parameters for compensating motions of patient bodies and/or motions of beams relative to patient bodies. Irreducible variations in tumour position are those random dislocations of a target that are related to errors intrinsic in the design and performance limitations of the software and hardware, as well as limitations of human perception and decision making. Thus, margins in the era of image-guided treatments will need to accommodate only random errors residual in patient setup accuracy (after image-guided setup corrections) and in the accuracy of systems designed to track moving and deforming tissues of the targeted regions of the patient's body. Therefore, construction of these margins will have to be based on purely statistical data. The characteristics of these data have to be determined through the central limit theorem and Gaussian properties of limiting error distributions. In this paper, we show how statistically determined margins are to be designed in the general case of correlated distributions of position errors in three-dimensional space. In particular, we show how the minimal margins for a given level of statistical confidence are found. Then, how they are to be used to determine geometrically minimal PTV that provides coverage of GTV at the assumed level of statistical confidence. Our results generalize earlier recommendations for statistical, central limit theorem

On probabilistically defined margins in radiation therapy

International Nuclear Information System (INIS)

Papiez, Lech; Langer, Mark

2006-01-01

Margins about a target volume subject to external beam radiation therapy are designed to assure that the target volume of tissue to be sterilized by treatment is adequately covered by a lethal dose. Thus, margins are meant to guarantee that all potential variation in tumour position relative to beams allows the tumour to stay within the margin. Variation in tumour position can be broken into two types of dislocations, reducible and irreducible. Reducible variations in tumour position are those that can be accommodated with the use of modern image-guided techniques that derive parameters for compensating motions of patient bodies and/or motions of beams relative to patient bodies. Irreducible variations in tumour position are those random dislocations of a target that are related to errors intrinsic in the design and performance limitations of the software and hardware, as well as limitations of human perception and decision making. Thus, margins in the era of image-guided treatments will need to accommodate only random errors residual in patient setup accuracy (after image-guided setup corrections) and in the accuracy of systems designed to track moving and deforming tissues of the targeted regions of the patient's body. Therefore, construction of these margins will have to be based on purely statistical data. The characteristics of these data have to be determined through the central limit theorem and Gaussian properties of limiting error distributions. In this paper, we show how statistically determined margins are to be designed in the general case of correlated distributions of position errors in three-dimensional space. In particular, we show how the minimal margins for a given level of statistical confidence are found. Then, how they are to be used to determine geometrically minimal PTV that provides coverage of GTV at the assumed level of statistical confidence. Our results generalize earlier recommendations for statistical, central limit theorem

Soil disturbance and 10-year growth response of coast Douglas-fir on nontilled and tilled skid trails in the Oregon Cascades.

Science.gov (United States)

Ronald Heninger; William Scott; Alex Dobkowski; Richard Miller; Harry Anderson; Steve Duke

2002-01-01

We (i) quantified effects of skidder yarding on soil properties and seedling growth in a portion of western Oregon, (ii) determined if tilling skid trails improved tree growth, and (iii) compared results with those from an earlier investigation in coastal Washington. Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings were hand planted at...

The homogeneous marginal utility of income assumption

NARCIS (Netherlands)

Demuynck, T.

2015-01-01

We develop a test to verify if every agent from a population of heterogeneous consumers has the same marginal utility of income function. This homogeneous marginal utility of income assumption is often (implicitly) used in applied demand studies because it has nice aggregation properties and

Development of the fuel and energy complex within the less demanding variant of Czechoslovak economy till 2000

International Nuclear Information System (INIS)

Kopac, P.; Blaha, J.; Maly, M.

1989-01-01

The character of the fuel and energy complex which has to serve national economy, requires that it be developed according to the needs and possibilities of national economy. A projection of social and economic development of Czechoslovakia till 2000 was set up by the Central Institute of National Economy Research and it was used as the basis of a scenario of the development of the fuel and energy complex. The results are given of modeling the development of the complex. (author). 6 tabs., 3 refs

Modeling spatial variability of sand-lenses in clay till settings using transition probability and multiple-point geostatistics

DEFF Research Database (Denmark)

Kessler, Timo Christian; Nilsson, Bertel; Klint, Knud Erik

2010-01-01

(TPROGS) of alternating geological facies. The second method, multiple-point statistics, uses training images to estimate the conditional probability of sand-lenses at a certain location. Both methods respect field observations such as local stratigraphy, however, only the multiple-point statistics can...... of sand-lenses in clay till. Sand-lenses mainly account for horizontal transport and are prioritised in this study. Based on field observations, the distribution has been modeled using two different geostatistical approaches. One method uses a Markov chain model calculating the transition probabilities...

Evaluation of margining algorithms in commercial treatment planning systems

International Nuclear Information System (INIS)

Pooler, Alistair M.; Mayles, Helen M.; Naismith, Olivia F.; Sage, John P.; Dearnaley, David P.

2008-01-01

Introduction: During commissioning of the Pinnacle (Philips) treatment planning system (TPS) the margining algorithm was investigated and was found to produce larger PTVs than Plato (Nucletron) for identical GTVs. Subsequent comparison of PTV volumes resulting from the QA outlining exercise for the CHHIP (Conventional or Hypofractionated High Dose IMRT for Prostate Ca.) trial confirmed that there were differences in TPS's margining algorithms. Margining and the clinical impact of the different PTVs in seven different planning and virtual simulation systems (Pinnacle, Plato, Prosoma (MedCom), Eclipse (7.3 and 7.5) (Varian), MasterPlan (Nucletron), Xio (CMS) and Advantage Windows (AW) (GE)) is investigated, and a simple test for 3D margining consistency is proposed. Methods: Using each TPS, two different sets of prostate GTVs on 2.5 mm and 5 mm slices were margined according to the CHHIP protocol to produce PTV3 (prostate + 5 mm/0 mm post), PTV2 (PTV3 + 5 mm) and PTV1 (prostate and seminal vesicles + 10 mm). GTVs and PTVs were imported into Pinnacle for volume calculation. DVHs for 5 mm slice plans, created using the smallest PTVs, were recalculated on the largest PTV dataset and vice versa. Since adding a margin of 50 mm to a structure should give the same result as adding five margins of 10 mm, this was tested for each TPS (consistency test) using an octahedron as the GTV and CT datasets with 2.5 mm and 5 mm slices. Results: The CHHIP PTV3 and PTV1 volumes had a standard deviation, across the seven systems, of 5% and PTV2 (margined twice) 9%, on the 5 mm slices. For 2.5 mm slices the standard deviations were 4% and 6%. The ratio of the Pinnacle and the Eclipse 7.3 PTV2 volumes was 1.25. Rectal doses were significantly increased when encompassing Pinnacle PTVs (V 50 42.8%), compared to Eclipse 7.3 PTVs (V 50 = 36.4%). Conversely, fields that adequately treated an Eclipse 7.3 PTV2 were inadequate for a Pinnacle PTV2. AW and Plato PTV volumes were the most consistent

Large margin image set representation and classification

KAUST Repository

Wang, Jim Jing-Yan; Alzahrani, Majed A.; Gao, Xin

2014-01-01

In this paper, we propose a novel image set representation and classification method by maximizing the margin of image sets. The margin of an image set is defined as the difference of the distance to its nearest image set from different classes and the distance to its nearest image set of the same class. By modeling the image sets by using both their image samples and their affine hull models, and maximizing the margins of the images sets, the image set representation parameter learning problem is formulated as an minimization problem, which is further optimized by an expectation - maximization (EM) strategy with accelerated proximal gradient (APG) optimization in an iterative algorithm. To classify a given test image set, we assign it to the class which could provide the largest margin. Experiments on two applications of video-sequence-based face recognition demonstrate that the proposed method significantly outperforms state-of-the-art image set classification methods in terms of both effectiveness and efficiency.

Large margin image set representation and classification

KAUST Repository

Wang, Jim Jing-Yan

2014-07-06

In this paper, we propose a novel image set representation and classification method by maximizing the margin of image sets. The margin of an image set is defined as the difference of the distance to its nearest image set from different classes and the distance to its nearest image set of the same class. By modeling the image sets by using both their image samples and their affine hull models, and maximizing the margins of the images sets, the image set representation parameter learning problem is formulated as an minimization problem, which is further optimized by an expectation - maximization (EM) strategy with accelerated proximal gradient (APG) optimization in an iterative algorithm. To classify a given test image set, we assign it to the class which could provide the largest margin. Experiments on two applications of video-sequence-based face recognition demonstrate that the proposed method significantly outperforms state-of-the-art image set classification methods in terms of both effectiveness and efficiency.

Solid/liquid partition coefficients (K{sub d}) and plant/soil concentration ratios (CR) for selected soils, tills and sediments at Forsmark

Energy Technology Data Exchange (ETDEWEB)

Sheppard, Steve (ECOMatters Inc. (Canada)); Sohlenius, Gustav (Sveriges geologiska undersoekning (Sweden)); Omberg, Lars-Gunnar (ALS Scandinavia AB (Sweden)); Borgiel, Mikael (Sveriges Vattenekologer AB (Sweden)); Grolander, Sara (Facilia AB (Sweden)); Norden, Sara (Svensk Kaernbraenslehantering AB (Sweden))

2011-11-15

Solid/liquid partition coefficients (K{sub d}) are used to indicate the relative mobility of radionuclides and elements of concern from nuclear fuel waste, as well as from other sources. To indicate the uptake of radionuclides in biota concentration ratios (CR) between soil and biota are used. This report summarized K{sub d} data for regolith and marine sediments based on concentrations of 69 indigenous stable elements measured from samples collected at the Forsmark site and CR data concerning cereals growing on these soils. The samples included 50 regolith samples from agricultural land and wetlands, 8 samples of till collected at different depths, and two marine sediment samples. In addition, cereal grains, stems and roots were collected from 4 sites for calculation of CRs. The regolith samples represented the major 5 deposits, which can be used as arable land, at the site (clayey till, glacial clay, clay gyttja and peat (cultivated and undisturbed)). K{sub d} values were generally lower for peat compared to clay soils. There were also clear differences in K{sub d} resulting from differences in soil chemistry within each regolith type. Soil pH was the most important factor, and K{sub d} values for many elements were lower in acidic clay soils compared to basic clay soils. Although there were only a few samples of sandy till and marine sediment, the K{sub d} values were generally consistent with the corresponding regolith K{sub d} values. Of the different cereal parts the grain always had the lowest CR. In most cases, the root CR was significantly higher than the grain CR, whereas only for a few elements were the grain and stem CR values different

Single-Center Experience Using Marginal Liver Grafts in Korea.

Science.gov (United States)

Park, P-J; Yu, Y-D; Yoon, Y-I; Kim, S-R; Kim, D-S

2018-05-01

Liver transplantation (LT) is an established therapeutic modality for patients with end-stage liver disease. The use of marginal donors has become more common worldwide due to the sharp increase in recipients, with a consequent shortage of suitable organs. We analyzed our single-center experience over the last 8 years in LT to evaluate the outcomes of using so-called "marginal donors." We retrospectively analyzed the database of all LTs performed at our institution from 2009 to 2017. Only patients undergoing deceased-donor LTs were analyzed. Marginal grafts were defined as livers from donors >60 years of age, livers from donors with serum sodium levels >155 mEq, graft steatosis >30%, livers with cold ischemia time ≥12 hours, livers from donors who were hepatitis B or C virus positive, livers recovered from donation after cardiac death, and livers split between 2 recipients. Patients receiving marginal grafts (marginal group) were compared with patients receiving standard grafts (standard group). A total of 106 patients underwent deceased-donor LT. There were 55 patients in the standard group and 51 patients in the marginal group. There were no significant differences in terms of age, sex, Model for End-Stage Liver Disease score, underlying liver disease, presence of hepatocellular carcinoma, and hospital stay between the 2 groups. Although the incidence of acute cellular rejection, cytomegalovirus infection, and postoperative complications was similar between the 2 groups, the incidence of early allograft dysfunction was higher in the marginal group. With a median follow-up of 26 months, the 1-, 3-, and 5-year overall and graft (death-censored) survivals in the marginal group were 85.5%, 75%, and 69.2% and 85.9%, 83.6%, and 77.2%, respectively. Patient overall survival and graft survival (death-censored) were significantly lower in the marginal group (P = .023 and P = .048, respectively). On multivariate analysis, receiving a marginal graft (hazard ratio [HR

Marginal-cost pricing for Hydro-Quebec residential customers

International Nuclear Information System (INIS)

Paquin, C.

1994-02-01

An option available to governments and to utilities such as Hydro-Quebec for responding to objectives of energy efficiency is the adoption of marginal cost pricing. Compared to currently used price structures, marginal cost pricing will allow improvement of price signals and assure an optimal utilization of the resource. That type of pricing could be economically beneficial but may not be desirable from the point of view of revenue distribution. Taking account of Hydro-Quebec's cost structure, pure marginal cost pricing would generate an income that would be strongly contested on equity grounds. For example, it would raise prices 60% for residential customers. Faced with this possibility, an analysis is presented of the impact of a peak-offpeak pricing (or pure marginal cost pricing) on Hydro-Quebec's residential customer energy bills. The marginal costs of Hydro-Quebec are calculated by the method of Bernard and Chatel (1985) and analysis of the results is based on Friedman and Weare (1993). A sample of 28,417 residential customers from a 1989 Hydro-Quebec survey is used in the study. Two scenarios are analyzed; the first allowing comparison of the energy bill only on the basis of marginal costs and of average costs, and the second allowing comparison of the impact of marginal cost pricing on the total bill. In the first scenario, the impact translates into a 31% increase in energy bills for the entire customer class considered; in addition, this impact is inversely proportional to the revenue class. In the second scenario, the increase is 24%. 33 refs., 10 figs., 53 tabs

How to make offshore marginal fields work for everyone

International Nuclear Information System (INIS)

Blandford, P.R.

1995-01-01

Marginal fields make positive impact on certain oil and gas companies' financial performances. These developments are integrated into the operator's operational and philosophical mindset, so that they optimize return and establish a reasonable reserve base for the company. Having a portfolio of marginal field developments is definitely a part of the offshore business, and oil field suppliers and subcontractors will continue to develop technology and methods to ensure the fields are exploited. It goes without saying that the continued production of marginal fields helps a lot of consumers and the companies that make up the energy chain that gets it to them. There are marginal fields all over the world and the market can only grow as more and more of the resources decline and industrialization expands demand. The projections for 2020 state that fossil fuels will remain the major supply link to dependable and affordable energy, particularly as additional oil and gas infrastructures are built and installed. Likened to the commodity, oil and gas companies and the energy industry have slowly evolved to the point where they are making a difference for people worldwide. As long as there is product to produce, most companies and consumers do not really care what type of reservoir started it all. More often then not, it probably started out as a marginal prospect. The paper discusses the energy picture today, marginal field update, offshore marginal field geography, and independent and marginal field developments

Exploring the Subtleties of Inverse Probability Weighting and Marginal Structural Models.

Science.gov (United States)

Breskin, Alexander; Cole, Stephen R; Westreich, Daniel

2018-05-01

Since being introduced to epidemiology in 2000, marginal structural models have become a commonly used method for causal inference in a wide range of epidemiologic settings. In this brief report, we aim to explore three subtleties of marginal structural models. First, we distinguish marginal structural models from the inverse probability weighting estimator, and we emphasize that marginal structural models are not only for longitudinal exposures. Second, we explore the meaning of the word "marginal" in "marginal structural model." Finally, we show that the specification of a marginal structural model can have important implications for the interpretation of its parameters. Each of these concepts have important implications for the use and understanding of marginal structural models, and thus providing detailed explanations of them may lead to better practices for the field of epidemiology.

The suitability of non-legume cover crops for inorganic soil nitrogen immobilisation in the transition period to an organic no-till system

Directory of Open Access Journals (Sweden)

Lars Rühlemann

2016-01-01

Full Text Available The aim of the study was to evaluate non-legume cover crops for growing no-till grain legumes in organic farming systems. Evaluated cover crops should be able to suppress weed growth, reduce plant available nitrogen in the soil and produce large amounts of biomass with slow N mineralisation. Six non-legume species; spring rye (Secale cereale L., black oat (Avena sativa L., sunflower (Helianthus annuus L., white mustard (Sinapis alba L., buckwheat (Fagopyrum esculentum Moench and hemp (Cannabis sativa L. were tested. Plots with organic fertiliser (50 kg N ha−1 and without fertiliser incorporation at three locations in south-east Germany were trialled and the cover crops’ ability to produce biomass and accumulate N in plant compartments was evaluated. The N mineralisation from stem and leaf material was simulated using the STICS model. The biomass production ranged from 0.95 to 7.73 Mg ha−1, with fertiliser increasing the total biomass at locations with low-N status. Sunflower consistently displayed large biomass and N accumulation at all locations and fertiliser variations, although not always significantly more than other species. Most N was stored in sunflower leaf material, which can be easily mineralised making it less suited as cover crop before no-till sown spring grain legumes. Rye, which produced slightly less biomass, but accumulated more N in the stem biomass, would be better suited than sunflower in this type of system. The N mineralisation simulation from rye biomass indicated long N immobilisation periods potentially improving weed suppression within no-till sown legume cash crops.

Values and marginal preferences in international business

NARCIS (Netherlands)

Maseland, Robbert; van Hoorn, Andre

2010-01-01

In a recent paper in this journal, Maseland and van Hoorn argued that values surveys tend to conflate values and marginal preferences. This assertion has been challenged by Brewer and Venaik, who claim that the wording of most survey items does not suggest that these elicit marginal preferences.

Jämnt Lärande : Ett illustrerat hjälpmedel till normkritisk granskning av läromedel

OpenAIRE

Denninger, Johan

2017-01-01

I detta examensarbete undersöks normbildande och reproducering av normer i samband med bilder i läromedel som används av modersmålslärare i Eskilstuna Kommun. Arbetet bygger på problematiken att stereotyper och reproducering av normer är vanligt förkommande i läromedlen samt att lärarnas brist på tid och möjlighet att granska läromedlen normkritiskt. Syftet med arbetet är att formge ett gestaltningsförslag till ett illustrerat hjälpmedel för normkritisk granskning av läromed...

Recent progress in Pacific-Asian Marginal Seas (PAMS) studies

Science.gov (United States)

Matsuno, Takeshi; Hirose, Naoki; Zhang, Jing; Cho, Yang-Ki; Chen, Dake; Yuan, Dongliang; Hung, Chin-Chang; Jan, Sen

2017-07-01

Marginal seas which represent the buffer zones between land and the pelagic ocean are being increasingly influenced by human activity. The role of the marginal seas is important for many reasons, among which are biological resources and climate change. In East Asia, we have marginal seas between the Asian Continent and the Pacific Ocean, where various countries and areas form complicated territories and EEZ. To understand the marine environment of marginal seas, international cooperative scientific activities are necessary, and it is essential to share the latest information and knowledge.

Ice marginal fluctuations during the Weichselian glaciation in Fennoscandia, a literature review

Energy Technology Data Exchange (ETDEWEB)

Lokrantz, Hanna; Sohlenius, Gustav [Geological Survey of Sweden, Uppsala (Sweden)

2006-12-15

were characterised by large re advances. The ice marginal deposits formed during Younger Dryas can be followed around the entire Fennoscandia. After the Younger Dryas the ice retreated more or less continuously. Deep weathered bedrock of Pre-Quaternary age occurs in parts of Smaaland and in the inner parts of northern Sweden. These deposits indicate low erosion during the Quaternary glacials in these regions. In the inner part of Norrbotten there are morphological features, Veiki moraines, which according to several authors were formed during the first Weichselian ice advance (MIS 5d). In Smaaland there are till covered eskers, which may have been formed prior to the latest glacial advance. Areas with deep weathered bedrock and those with Quaternary deposits older than the last glaciation coincide to a large extent. These areas are indicators of cold based ice and of low glacial erosion.

Ice marginal fluctuations during the Weichselian glaciation in Fennoscandia, a literature review

International Nuclear Information System (INIS)

Lokrantz, Hanna; Sohlenius, Gustav

2006-12-01

were characterised by large re advances. The ice marginal deposits formed during Younger Dryas can be followed around the entire Fennoscandia. After the Younger Dryas the ice retreated more or less continuously. Deep weathered bedrock of Pre-Quaternary age occurs in parts of Smaaland and in the inner parts of northern Sweden. These deposits indicate low erosion during the Quaternary glacials in these regions. In the inner part of Norrbotten there are morphological features, Veiki moraines, which according to several authors were formed during the first Weichselian ice advance (MIS 5d). In Smaaland there are till covered eskers, which may have been formed prior to the latest glacial advance. Areas with deep weathered bedrock and those with Quaternary deposits older than the last glaciation coincide to a large extent. These areas are indicators of cold based ice and of low glacial erosion

The stability margin on EAST tokamak

International Nuclear Information System (INIS)

Jin-Ping, Qian; Bao-Nian, Wan; Biao, Shen; Bing-Jia, Xiao; Walker, M.L.; Humphreys, D.A.

2009-01-01

The experimental advanced superconducting tokamak (EAST) is the first full superconducting tokamak with a D-shaped cross-sectional plasma presently in operation. Its poloidal coils are relatively far from the plasma due to the necessary thermal isolation from the superconducting magnets, which leads to relatively weaker coupling between plasma and poloidal field. This may cause more difficulties in controlling the vertical instability by using the poloidal coils. The measured growth rates of vertical stability are compared with theoretical calculations, based on a rigid plasma model. Poloidal beta and internal inductance are varied to investigate their effects on the stability margin by changing the values of parameters α n and γ n (Howl et al 1992 Phys. Fluids B 4 1724), with plasma shape fixed to be a configuration with k = 1.9 and δ = 0.5. A number of ways of studying the stability margin are investigated. Among them, changing the values of parameters κ and l i is shown to be the most effective way to increase the stability margin. Finally, a guideline of stability margin M s (κ, l i , A) to a new discharge scenario showing whether plasmas can be stabilized is also presented in this paper

Fedme og risiko for marginal parodontitis

DEFF Research Database (Denmark)

Kongstad, Johanne; Keller, Amélie Cléo; Rohde, Jeanett Friis

2017-01-01

Oversigtsartiklen, der er af narrativ karakter, beskriver sammenhængen mellem overvægt/ fedme og marginal parodontitis. Artiklen er baseret på et udvalg af nyere engelsksproget litteratur og motiveres af den øgede forekomst af overvægtige og fede i befolkningen. Desuden er det afgørende, at tandl......Oversigtsartiklen, der er af narrativ karakter, beskriver sammenhængen mellem overvægt/ fedme og marginal parodontitis. Artiklen er baseret på et udvalg af nyere engelsksproget litteratur og motiveres af den øgede forekomst af overvægtige og fede i befolkningen. Desuden er det afgørende......, at tandlæger forholder sig kritisk til systemiske tilstandes mulige konsekvens for udvikling, forværring og behandling af marginal parodontitis. Der nævnes forskellige mål for fedme, hvor body mass index (BMI) og taljeomkreds er de mest anvendte. Problematikken vedrørende tidligere studiers anvendelse af...... forskellige kriterier for marginal parodontitis berøres. Litteraturgennemgangen tager udgangspunkt i de biologiske mekanismer, der udløses i fedtvæv ved overvægt/fedme og medfører en kronisk inflammatorisk tilstand med frigivelse af bl.a. adipokiner. Epidemiologiske tværsnitsog longitudinelle studier af...

Refining prices and margins in 1998

International Nuclear Information System (INIS)

Favennec, J.P.; Baudoin, C.

1999-01-01

Despite a business environment that was globally mediocre due primarily to the Asian crisis and to a mild winter in the northern hemisphere, the signs of improvement noted in the refining activity in 1996 were borne out in 1997. But the situation is not yet satisfactory in this sector: the low return on invested capital and the financing of environmental protection expenditure are giving cause for concern. In 1998, the drop in crude oil prices and the concomitant fall in petroleum product prices was ultimately rather favorable to margins. Two elements tended to put a damper on this relative optimism. First of all, margins continue to be extremely volatile and, secondly, the worsening of the economic and financial crisis observed during the summer made for a sharp decline in margins in all geographic regions, especially Asia

Realistic respiratory motion margins for external beam partial breast irradiation

Energy Technology Data Exchange (ETDEWEB)

Conroy, Leigh; Quirk, Sarah [Department of Medical Physics, Tom Baker Cancer Centre, Calgary, Alberta T2N 4N2 (Canada); Department of Physics and Astronomy, University of Calgary, Calgary, Alberta T2N 1N4 (Canada); Smith, Wendy L., E-mail: wendy.smith@albertahealthservices.ca [Department of Medical Physics, Tom Baker Cancer Centre, Calgary, Alberta T2N 4N2 (Canada); Department of Physics and Astronomy, University of Calgary, Calgary, Alberta T2N 1N4 (Canada); Department of Oncology, University of Calgary, Calgary, Alberta T2N 1N4 (Canada)

2015-09-15

Purpose: Respiratory margins for partial breast irradiation (PBI) have been largely based on geometric observations, which may overestimate the margin required for dosimetric coverage. In this study, dosimetric population-based respiratory margins and margin formulas for external beam partial breast irradiation are determined. Methods: Volunteer respiratory data and anterior–posterior (AP) dose profiles from clinical treatment plans of 28 3D conformal radiotherapy (3DCRT) PBI patient plans were used to determine population-based respiratory margins. The peak-to-peak amplitudes (A) of realistic respiratory motion data from healthy volunteers were scaled from A = 1 to 10 mm to create respiratory motion probability density functions. Dose profiles were convolved with the respiratory probability density functions to produce blurred dose profiles accounting for respiratory motion. The required margins were found by measuring the distance between the simulated treatment and original dose profiles at the 95% isodose level. Results: The symmetric dosimetric respiratory margins to cover 90%, 95%, and 100% of the simulated treatment population were 1.5, 2, and 4 mm, respectively. With patient set up at end exhale, the required margins were larger in the anterior direction than the posterior. For respiratory amplitudes less than 5 mm, the population-based margins can be expressed as a fraction of the extent of respiratory motion. The derived formulas in the anterior/posterior directions for 90%, 95%, and 100% simulated population coverage were 0.45A/0.25A, 0.50A/0.30A, and 0.70A/0.40A. The differences in formulas for different population coverage criteria demonstrate that respiratory trace shape and baseline drift characteristics affect individual respiratory margins even for the same average peak-to-peak amplitude. Conclusions: A methodology for determining population-based respiratory margins using real respiratory motion patterns and dose profiles in the AP direction was

Realistic respiratory motion margins for external beam partial breast irradiation

International Nuclear Information System (INIS)

Conroy, Leigh; Quirk, Sarah; Smith, Wendy L.

2015-01-01

Purpose: Respiratory margins for partial breast irradiation (PBI) have been largely based on geometric observations, which may overestimate the margin required for dosimetric coverage. In this study, dosimetric population-based respiratory margins and margin formulas for external beam partial breast irradiation are determined. Methods: Volunteer respiratory data and anterior–posterior (AP) dose profiles from clinical treatment plans of 28 3D conformal radiotherapy (3DCRT) PBI patient plans were used to determine population-based respiratory margins. The peak-to-peak amplitudes (A) of realistic respiratory motion data from healthy volunteers were scaled from A = 1 to 10 mm to create respiratory motion probability density functions. Dose profiles were convolved with the respiratory probability density functions to produce blurred dose profiles accounting for respiratory motion. The required margins were found by measuring the distance between the simulated treatment and original dose profiles at the 95% isodose level. Results: The symmetric dosimetric respiratory margins to cover 90%, 95%, and 100% of the simulated treatment population were 1.5, 2, and 4 mm, respectively. With patient set up at end exhale, the required margins were larger in the anterior direction than the posterior. For respiratory amplitudes less than 5 mm, the population-based margins can be expressed as a fraction of the extent of respiratory motion. The derived formulas in the anterior/posterior directions for 90%, 95%, and 100% simulated population coverage were 0.45A/0.25A, 0.50A/0.30A, and 0.70A/0.40A. The differences in formulas for different population coverage criteria demonstrate that respiratory trace shape and baseline drift characteristics affect individual respiratory margins even for the same average peak-to-peak amplitude. Conclusions: A methodology for determining population-based respiratory margins using real respiratory motion patterns and dose profiles in the AP direction was

17 CFR 41.47 - Withdrawal of margin.

Science.gov (United States)

2010-04-01

... PRODUCTS Customer Accounts and Margin Requirements § 41.47 Withdrawal of margin. (a) By the customer... positions in the account under this Regulation (Subpart E, §§ 41.42 through 41.49). (b) By the security...) Interest charged on credit maintained in the account; (3) Communication or shipping charges with respect to...

Double-sided Moral Hazard and Margin-based Royalty

OpenAIRE

NARIU, Tatsuhiko; UEDA, Kaoru; LEE, DongJoon

2009-01-01

This paper analyzes royalty modes in the franchise arrangements of convenience stores under double-sided moral hazard. In Japan, the majority of franchisors charge margin-based royalties based on net margins rather than sales-based royalties based on sales. We show that the franchisor can attain the first-best outcome by adopting margin-based royalties under double-sided moral hazard. We consider a case where a franchisee sells two kinds of goods; one is shipped from its franchisor and the ot...

Time Safety Margin: Theory and Practice

Science.gov (United States)

2016-09-01

Air Education and Training Command Handbook 99-107, T-38 Road to Wings, Randolph Air Force Base, Texas, July 2013. 65 This page was intentionally left...412TW-TIH-16-01 TIME SAFETY MARGIN: THEORY AND PRACTICE WILLIAM R. GRAY, III Chief Test Pilot USAF Test Pilot School SEPTEMBER 2016... Safety Margin: The01y and Practice) was submitted by the Commander, 4 I 2th Test Wing, Edwards AFB, Ca lifornia 93524-6843. Foreign announcement and

Benefit–cost analysis of non-marginal climate and energy projects

International Nuclear Information System (INIS)

Dietz, Simon; Hepburn, Cameron

2013-01-01

Conventional benefit–cost analysis incorporates the normally reasonable assumption that the policy or project under examination is marginal. Among the assumptions this entails is that the policy or project is small, so the underlying growth rate of the economy does not change. However, this assumption may be inappropriate in some important circumstances, including in climate-change and energy policy. One example is global targets for carbon emissions, while another is a large renewable energy project in a small economy, such as a hydropower dam. This paper develops some theory on the evaluation of non-marginal projects, with empirical applications to climate change and energy. We examine the conditions under which evaluation of a non-marginal project using marginal methods may be wrong, and in our empirical examples we show that both qualitative and large quantitative errors are plausible. - Highlights: • This paper develops the theory of the evaluation of non-marginal projects. • It also includes empirical applications to climate change and energy. • We show when evaluation of a non-marginal project using marginal methods is wrong

TILLING in the two-rowed barley cultivar 'Barke' reveals preferred sites of functional diversity in the gene HvHox1

Directory of Open Access Journals (Sweden)

Komatsuda Takao

2009-12-01

Full Text Available Abstract Background The economic importance of cereals such as barley, and the demand for improved yield and quality require a better understanding of the genetic components that modulate biologically and commercially relevant traits. While Arabidopsis thaliana is the premiere model plant system, the spectrum of its traits cannot address all of the fundamental questions of crop plant development. Unlike Arabidopsis, barley is both a crop and a model system for scientific research, and it is increasingly being used for genetic and molecular investigations into the conserved biological processes of cereals. A common challenge in genetic studies in plants with large genomes arises from the very time-consuming work of associating mutant phenotypes with gene sequence information, especially if insertion mutagenesis is not routine, as in barley. Reverse genetics based on chemical mutagenesis represents the best solution to this obstacle. Findings In barley, we generated a new TILLING (Targeting Local Lesions IN Genomes resource comprising 10,279 M2 mutants in the two-rowed malting cultivar 'Barke,' which has been used in the generation of other genomic resources in barley (~150,000 ESTs, DH mapping population. The value of this new resource was tested using selected candidate genes. An average frequency of approximately one mutation per 0.5 Mb was determined by screening ten fragments of six different genes. The ethyl methanesulphonate (EMSmutagenesis efficiency was studied by recording and relating the mutagenesis-dependent effects found in the three mutant generations (M1-M3. A detailed analysis was performed for the homeodomain-leucine-zipper (HD-ZIP gene HvHox1. Thirty-one mutations were identified by screening a 1,270-bp fragment in 7,348 M2 lines. Three of the newly identified mutants exhibited either a six-rowed or an intermedium-spike phenotype, and one mutant displayed a significantly altered spikelet morphology compared to that of the 'Barke

30 CFR 204.3 - What alternatives are available for marginal properties?

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What alternatives are available for marginal... MINERALS REVENUE MANAGEMENT ALTERNATIVES FOR MARGINAL PROPERTIES General Provisions § 204.3 What alternatives are available for marginal properties? If you have production from a marginal property, MMS and...

Margination of Stiffened Red Blood Cells Regulated By Vessel Geometry.

Science.gov (United States)

Chen, Yuanyuan; Li, Donghai; Li, Yongjian; Wan, Jiandi; Li, Jiang; Chen, Haosheng

2017-11-10

Margination of stiffened red blood cells has been implicated in many vascular diseases. Here, we report the margination of stiffened RBCs in vivo, and reveal the crucial role of the vessel geometry in the margination by calculations when the blood is seen as viscoelastic fluid. The vessel-geometry-regulated margination is then confirmed by in vitro experiments in microfluidic devices, and it establishes new insights to cell sorting technology and artificial blood vessel fabrication.

Criticality safety margins for mixtures of fissionable materials

International Nuclear Information System (INIS)

Williamson, T.G.; Mincey, J.F.

1992-01-01

In the determination of criticality safety margins, approximations for combinations of fissile and fissionable isotopes are sometimes used that go by names such as the rule of fractions or equivalency relations. Use of the rule of fractions to ensure criticality safety margins was discussed in an earlier paper. The purpose of this paper is to correct errors and to clarify some of the implications. Deviations of safety margins from those calculated by the rule of fractions are still noted; however, the deviations are less severe. Caution in applying such rules is still urged. In general, these approximations are based on American National Standard ANSI/ANS-8.15, Sec. 5.2. This section allows that ratios of material masses to their limits may be summed for fissile nuclides in aqueous solutions. It also allows the addition of nonfissile nuclides if an aqueous moderator is present and addresses the effects of infinite water or equivalent reflector. Water-reflected binary combinations of aqueous solutions of fissile materials, as well as binary combinations of fissile and fissionable metals, were considered. Some combinations were shown to significantly decrease the margin of subcriticality compared to the single-unit margins. In this study, it is confirmed that some combinations of metal units in an optimum geometry may significantly decrease the margin of subcriticality. For some combinations of aqueous solutions of fissile materials, the margin of subcriticality may also be reduced by very small amounts. The conclusion of Ref. 1 that analysts should be careful in applying equivalency relations for combining materials remains valid and sound advice. The ANSI/ANS standard, which allows the use of ratios of masses to their limits, applies to aqueous, fully water-reflected, single-unit solutions. Extensions to other situations should be considered with extreme care

Evaluation of motion management strategies based on required margins

International Nuclear Information System (INIS)

Sawkey, D; Svatos, M; Zankowski, C

2012-01-01

Strategies for delivering radiation to a moving lesion each require a margin to compensate for uncertainties in treatment. These motion margins have been determined here by separating the total uncertainty into components. Probability density functions for the individual sources of uncertainty were calculated for ten motion traces obtained from the literature. Motion margins required to compensate for the center of mass motion of the clinical treatment volume were found by convolving the individual sources of uncertainty. For measurements of position at a frequency of 33 Hz, system latency was the dominant source of positional uncertainty. Averaged over the ten motion traces, the motion margin for tracking with a latency of 200 ms was 4.6 mm. Gating with a duty cycle of 33% required a mean motion margin of 3.2–3.4 mm, and tracking with a latency of 100 ms required a motion margin of 3.1 mm. Feasible reductions in the effects of the sources of uncertainty, for example by using a simple prediction algorithm to anticipate the lesion position at the end of the latency period, resulted in a mean motion margin of 1.7 mm for tracking with a latency of 100 ms, 2.4 mm for tracking with a latency of 200 ms, and 2.1–2.2 mm for the gating strategies with duty cycles of 33%. A crossover tracking latency of 150 ms was found, below which tracking strategies could take advantage of narrower motion margins than gating strategies. The methods described here provide a means to guide selection of a motion management strategy for a given patient. (paper)

Sustainable food production in marginal lands—Case of GDLA member countries

Directory of Open Access Journals (Sweden)

Shabbir A. Shahid

2013-06-01

Full Text Available Sustainable food production in the changing climate and dwindling water resources in the Global Dry Land Alliance (GDLA member countries is a real challenge, especially when considering marginal lands in dryland systems. The definition of marginal land is very vague and defined from different perspectives (pragmatism about marginal lands. Dryland itself indicates "marginality" due to water stress. In general, the abandoned agriculture land where food production is not economical, and has low inherent productivity potential is considered marginal; however, a land may be marginal for agriculture but vital for grazing. In this paper attempts have been made to give review of literature (water stress, extent of marginal saline lands, marginality. Policy matters (development of soil, water and agriculture strategies that GDLA and member countries should consider for future sustainable food production in their countries, including but not limited to, assessment of land resources for agriculture potential, defining, mapping and characterizing marginal lands, and use of innovative technologies (conservation agriculture, climate smart agriculture, integrated soil reclamation program and capacity building for food production, are discussed. The international perception (FAO, UNEP, CGIAR on marginal lands is also described. An innovative approach of using national biocapacity and ecological footprint is used to assess marginality of GDLA member countries. Ecological overshoot (using 1.5 earth planets and biocapacity debtor and creditor countries are highlighted. Challenges and best management practices for food production in marginal lands are included. Other important issues, like leasing land abroad, GDLA strategic food reserves and best management practices, innovative ideas for food production are shared. Finally recommendations are drafted for actions by GDLA, its member countries and the partners.

Identifying technology innovations for marginalized smallholders-A conceptual approach.

Science.gov (United States)

Malek, Mohammad Abdul; Gatzweiler, Franz W; Von Braun, Joachim

2017-05-01

This paper adds a contribution in the existing literature in terms of theoretical and conceptual background for the identification of idle potentials of marginal rural areas and people by means of technological and institutional innovations. The approach follows ex-ante assessment for identifying suitable technology and institutional innovations for marginalized smallholders in marginal areas-divided into three main parts (mapping, surveying and evaluating) and several steps. Finally, it contributes to the inclusion of marginalized smallholders by an improved way of understanding the interactions between technology needs, farming systems, ecological resources and poverty characteristics in the different segments of the poor, and to link these insights with productivity enhancing technologies.

Epidemiological features of scabies and STI in the Saratov area from 1991 till 2010

Directory of Open Access Journals (Sweden)

Reshetnikova E.M.

2012-06-01

Full Text Available

The study presents the comparative analysis of scabies and STI incidence in different groups of population in Saratov region from 1991 till 2010. Principal causes and factors supporting epidemic process of infectious diseases in this region on an extent of 2 decades are revealed. It is established that if the basic group patients with scabies were children, teenagers and people at the age from 20 to 29 years, so, in the group with STI there were patients aged from 18 to 29 years. Besides, it was proved that over the last years early and late latent forms of syphilis and neurosyphilis prevail among patients in age group from 40 to 60 years. It leads to disability, and sometimes invalidism quite often.

Evaluation of the marginal fit of metal copings fabricated on three different marginal designs using conventional and accelerated casting techniques: An in vitro study

Directory of Open Access Journals (Sweden)

Sharad Vaidya

2014-01-01

Conclusion: Among the three marginal designs studied, shoulder with bevel showed the best marginal fit with conventional as well as accelerated casting techniques. Accelerated casting technique could be a vital alternative to the time-consuming conventional casting technique. The marginal fit between the two casting techniques showed no statistical difference.

Till receipts--a new approach for investigating outbreaks? Evaluation during a large Salmonella Enteritidis phage type 14b outbreak in a North West London takeaway restaurant, September 2009.

Science.gov (United States)

Zenner, D; Zoellner, J; Charlett, A; Marmairis, W; Lane, C; Chow, J Y

2014-07-10

Selecting suitable controls for outbreak investigations is often difficult and if done inappropriately will lead to biased inferences. Till receipts and other sales records are frequently available on food premises, but their applicability has not been fully explored. Using data from an investigation into a Salmonella outbreak affecting 66 individuals exposed in a London takeaway restaurant, this study aimed to evaluate the use of till receipts to assess associations between sales and illness. Cases identified through local case-finding were subjected to a standardised exposure questionnaire. Till receipts over the time period when cases arose were analysed. Estimated food exposures from sales were compared to case reported exposures and till receipts analysis showed strong association between illness and consumption of rotisserie chicken (odds ratio (OR): 2.75; confidence interval (CI): 1.7-4.5). Chicken sales immediately prior to food consumption for cases were compared to two control periods in an ecological case-crossover design. On average there was an estimated increase of 3.7 (CI: 2.2-5.2) extra chickens sold in the hour immediately prior to the consumption in the cases (p<0.0001) and the risk of becoming ill at busy times increased by 5% with each additional chicken quarter sold per hour (OR: 1.05; CI: 1.03-1.08). Microbiological and environmental investigations revealed Salmonella Enteritidis phage type (PT)14b in all available cases' stool samples, two environmental samples and leftover chicken from the takeaway. The feasibility of this novel approach to obtain exposure information in the population at risk has been demonstrated, and its limitations are discussed. Further validation is required, comparing results with those in a concurrent classic case-control study.

Nudge; en knuff i rätt riktning? : Ett beteendeekonomiskt experiment om svenskars attityder till nudge

OpenAIRE

Öqvist, Johanna; Bergfelt, Petra

2015-01-01

Beteendeinterventioner – så kallade nudge – syftar till att få individer att ta beslut som är gynnsamma både för individ och samhälle genom att göra subtila förändringar i den miljö inom vilken individer tar beslut. Beslutsfattare världen över har börjat använda nudge som ytterligare ett policy-verktyg. Nudge har emellertid kritiserats för dess tvivelaktiga etiska principer och debatten om nudge har i stort sett fortskridit utan inflytande från allmänheten. För i vilken utsträckning anses nud...

Marginal Accuracy of Castings Produced with Different Investment Systems.

Science.gov (United States)

Yadav, R K

2009-04-01

The use of casting ring to produce accurate castings has been challenged with the introduction of a ringless casting technique. This study compared the marginal accuracy of all - metal complete coverage crowns fabricated with ringless, split plastic ring and metal ring investment systems. A total of 40 all- metal complete coverage crowns were fabricated on a metal die. The crowns were divided in 4 groups (Group A, B, C and D) of 10 patterns each. A ringless system of investing and casting was used for group A whereas a split plastic ring system was used for group B. Groups C and D utilized metal ring with single and double layers of asbestos free cellulose acetate liner respectively for investing and casting procedures. The restorations were seated on the metal die and the vertical marginal discrepancy was evaluated by measuring the gap between the finish line on the die and the margins of the crown on four specific sites with an optical microscope. Statistical analysis was carried out using ANOVA and multiple comparison "t" test. The mean vertical marginal discrepancy for groups A, B, C and D was 95μm, 136μm, 128μm and 104μm respectively. Vertical marginal discrepancy on each surface was compared among the four groups. Difference of vertical marginal discrepancy on buccal surface (p0.05). Accurate castings with better marginal fit can be produced with ringless casting technique.

Influence of Crack Morphology on Leak Before Break Margins

International Nuclear Information System (INIS)

Weilin Zang

2007-11-01

The purpose of the project is to evaluate the deterministic LBB-margins for different pipe systems in a Swedish PWR-plant and using different crack morphology parameters. Results: - The influence of crack morphology on Leak Before Break (LBB) margins is studied. The subject of the report is a number of LBB-submittals to SKI where deterministic LBB-margins are reported. These submittals typically uses a surface roughness of 0.0762 mm (300 microinch) and number of turns equal to zero and an in-house code for the leak rate evaluations. The present report has shown that these conditions give the largest LBB-margins both in terms of the quotient between the critical crack length and the leakage crack size and for the leak rate margin. - Crack morphology parameters have a strong influence on the leak rate evaluations. Using the SQUIRT code and more recent recommendations for crack morphology parameters, it is shown that in many cases the evaluated margins, using 1 gpm as the reference leak rate detection limit, are below the safety factor of 2 on crack size and 10 on leak rate, which is generally required for LBB approval. - The effect of including weld residual stresses on the LBB margins is also investigated. It is shown that for the two examples studied, weld residual stresses were important for the small diameter thin wall pipe whereas it was negligible for the large diameter thick wall pipe which had a self-balanced weld residual stress distribution

Marginal adaptation of composite resins under two adhesive techniques.

Science.gov (United States)

Dačić, Stefan; Veselinović, Aleksandar M; Mitić, Aleksandar; Nikolić, Marija; Cenić, Milica; Dačić-Simonović, Dragica

2016-11-01

In the present research, different adhesive techniques were used to set up fillings with composite resins. After the application of etch and rinse or self etch adhesive technique, marginal adaptation of composite fillings was estimated by the length of margins without gaps, and by the microretention of resin in enamel and dentin. The study material consisted of 40 extracted teeth. Twenty Class V cavities were treated with 35% phosphorous acid and restored after rinsing by Adper Single Bond 2 and Filtek Ultimate-ASB/FU 3M ESPE composite system. The remaining 20 cavities were restored by Adper Easy One-AEO/FU 3M ESPE composite system. Marginal adaptation of composite fillings was examined using a scanning electron microscope (SEM). The etch and rinse adhesive technique showed a significantly higher percentage of margin length without gaps (in enamel: 92.5%, in dentin: 57.3%), compared with the self-etch technique with lower percentage of margin length without gaps, in enamel 70.4% (p resin tugs in interprismatic spaces of enamel, while the dentin microretention was composed of adhesive and hybrid layers with resin tugs in dentin canals. In the second technique, resin tugs were rarely seen and a microgap was dominant along the border of restoration margins. The SEM analysis showed a better marginal adaptation of composite resin to enamel and dentin with better microretention when the etch and rinse adhesive procedure was applied. © 2016 Wiley Periodicals, Inc.

Technical specification improvement through safety margin considerations

International Nuclear Information System (INIS)

Howard, R.C.; Jansen, R.L.

1986-01-01

Westinghouse has developed an approach for utilizing safety analysis margin considerations to improve plant operability through technical specification revision. This approach relies on the identification and use of parameter interrelations and sensitivities to identify acceptable operating envelopes. This paper summarizes technical specification activities to date and presents the use of safety margin considerations as another viable method to obtain technical specification improvement

Pattern of Failure After Limited Margin Radiotherapy and Temozolomide for Glioblastoma

International Nuclear Information System (INIS)

McDonald, Mark W.; Shu, Hui-Kuo G.; Curran, Walter J.; Crocker, Ian R.

2011-01-01

Purpose: To evaluate the pattern of failure after limited margin radiotherapy for glioblastoma. Methods and Materials: We analyzed 62 consecutive patients with newly diagnosed glioblastoma treated between 2006 and 2008 with standard fractionation to a total dose of 60Gy with concurrent temozolomide (97%) or arsenic trioxide (3%). The initial clinical target volume included postoperative T2 abnormality with a median margin of 0.7cm. The boost clinical target volume included residual T1-enhancing tumor and resection cavity with a median margin of 0.5cm. Planning target volumes added a 0.3- or 0.5-cm margin to clinical target volumes. The total boost planning target volume (PTV boost ) margin was 1cm or less in 92% of patients. The volume of recurrent tumor (new T1 enhancement) was categorized by the percent within the 60-Gy isodose line as central (>95%), infield (81-95%), marginal (20-80%), or distant ( boost with a 2.5-cm margin were created for each patient. Results: With a median follow-up of 12 months, radiographic tumor progression developed in 43 of 62 patients. Imaging was available for analysis in 41: 38 (93%) had central or infield failure, 2 (5%) had marginal failure, and 1 (2%) had distant failure relative to the 60-Gy isodose line. The treated PTV boost (median, 140cm 3 ) was, on average, 70% less than the PTV boost with a 2.5-cm margin (median, 477cm 3 ) (p boost margin of 1cm or less did not appear to increase the risk of marginal and/or distant tumor failures compared with other published series. With careful radiation planning and delivery, it appears that treatment margins for glioblastoma can be reduced.

Stroke: a Hidden Danger of Margin Trading in Stock Markets.

Science.gov (United States)

Lin, Shu-Hui; Wang, Chien-Ho; Liu, Tsai-Ching; Chen, Chin-Shyan

2015-10-01

Using 10-year population data from 2000 through 2009 in Taiwan, this is the first paper to analyze the relationship between margin trading in stock markets and stroke hospitalizations. The results show that 3 and 6 days after an increase of margin trading in the Taiwan stock markets are associated with greater stoke hospitalizations. In general, a 1 % increase in total margin trading positions is associated with an increment of 2.5 in the total number of stroke hospitalizations, where the mean number of hospital admissions is 233 cases a day. We further examine the effects of margin trading by gender and age groups and find that the effects of margin trading are significant for males and those who are 45-74 years old only. In summary, buying stocks with money you do not have is quite risky, especially if the prices of those stocks fall past a certain level or if there is a sudden and severe drop in the stock market. There is also a hidden danger to one's health from margin trading. A person should be cautious before conducting margin trading, because while it can be quite profitable, danger always lurks just around the corner.

Den komplexa väven Att organisera för barns övergångar till och från förskoleklass

Directory of Open Access Journals (Sweden)

Helena Ackesjö

2015-09-01

Full Text Available This study focuses on how children's transitions to and from preschool classes are organized in different schools. Principal’s arguments for this organization were sought via a web-based survey and analyzed using the frame factor theory in addition to theories of practical sense and the concept of continuity. The results show that children tend to make more transitions between social communities the younger they are. The distribution of the principal’s answers show that the majority of them, because of external conditions, split the preschool groups to new classes in the transition to preschool class. However, the same movements are not indicated in the transition to first grade. The results show how the work of organizing chidren’s transitions represent a complex web of external actual conditions as the number of children and the recruitment area of the school, the internal logics and ideas about what is best for children and best for continued learning as well as the school's own traditions of working with transitions. Föreliggande studie fokuserar på hur barns övergångar till och från förskoleklass organiseras på olika skolor. Via en webbaserad enkät söks skolledares argument för denna organisering. I analysen nyttjas ett ramfaktorteoretiskt tänkande som kompletteras med teorier om praktiskt förnuft samt kontinuitetsbegreppet. Resultaten visar att barn tenderar att göra fler övergångar mellan barngrupper och sociala gemenskaper ju yngre de är. Fördelningen av skolledarnas svar visar att majoriteten, på grund av yttre villkor, delar förskolegrupperna till nya klasser i övergången till förskoleklass. Däremot indikeras inte samma rörlighet i övergången till årskurs 1. Resultaten visar hur arbetet med att organisera övergångarna utgör en komplex väv av yttre faktiska villkor som barnantal och upptagningsområdets storlek, av inre logiker och föreställningar om vad som är det bästa för barnen och det b

Studying media at The Margins: learning from the field

Directory of Open Access Journals (Sweden)

Clemencia Rodríguez

2016-07-01

Full Text Available This article, informed by ethnographic research on media at the margins, proposes a shift in perspective at several different levels: 1 instead of focusing on individual technologies, our research should examine how grassroots communicators operating at the margins exist in a media ecology that offers different potentialities in each historical situation; 2 instead of trying to determine if the media technologies used at the margin are old or new, digital or not digital, we need to explore how embedded community communicators detect local information or communication needs and use available technologies to address these needs; 3 our research on media at the margins should shed light on how grassroots communicators re-invent, hybridize, converge, and bridge technologies from one platform to another. In sum, understanding media at the margins is about embracing complexity, maintaining the notion of media ecologies, and understanding how grassroots communicators, deeply embedded in local contexts, wedge media technologies into everyday life.

Uplift history of a transform continental margin revealed by the stratigraphic record: The case of the Agulhas transform margin along the Southern African Plateau

Science.gov (United States)

Baby, Guillaume; Guillocheau, François; Boulogne, Carl; Robin, Cécile; Dall'Asta, Massimo

2018-04-01

The south and southeast coast of southern Africa (from 28°S to 33°S) forms a high-elevated transform passive margin bounded to the east by the Agulhas-Falkland Fracture Zone (AFFZ). We analysed the stratigraphic record of the Outeniqua and Durban (Thekwini) Basins, located on the African side of the AFFZ, to determine the evolution of these margins from the rifting stage to present-day. The goal was to reconstruct the strike-slip evolution of the Agulhas Margin and the uplift of the inland high-elevation South African Plateau. The Agulhas transform passive margin results from four successive stages: Rifting stage, from Late Triassic to Early Cretaceous ( 200?-134 Ma), punctuated by three successive rifting episodes related to the Gondwana breakup; Wrench stage (134-131 Ma), evidenced by strike- and dip-slip deformations increasing toward the AFFZ; Active transform margin stage (131-92 Ma), during which the Falkland/Malvinas Plateau drifts away along the AFFZ, with an uplift of the northeastern part of the Outeniqua Basin progressively migrating toward the west; Thermal subsidence stage (92-0 Ma), marked by a major change in the configuration of the margin (onset of the shelf-break passive margin morphology). Two main periods of uplift were documented during the thermal subsidence stage of the Agulhas Margin: (1) a 92 Ma short-lived margin-scale uplift, followed by a second one at 76 Ma located along the Outeniqua Basin and; (2) a long-lasting uplift from 40 to 15 Ma limited to the Durban (Thekwini) Basin. This suggests that the South African Plateau is an old Upper Cretaceous relief (90-70 Ma) reactivated during Late Eocene to Early Miocene times (40-15 Ma).

Bed-Deformation Experiments Beneath a Temperate Glacier

Science.gov (United States)

Iverson, N. R.; Hooyer, T. S.; Fischer, U. H.; Cohen, D.; Jackson, M.; Moore, P. L.; Lappegard, G.; Kohler, J.

2002-12-01

Fast flow of glaciers and genesis of glacial landforms are commonly attributed to shear deformation of subglacial sediment. Although models of this process abound, data gathered subglacially on the kinematics and mechanics of such deformation are difficult to interpret. Major difficulties stem from the necessity of either measuring deformation near glacier margins, where conditions may be abnormal, or at the bottoms of boreholes, where the scope of instrumentation is limited, drilling disturbs sediment, and local boundary conditions are poorly known. A different approach is possible at the Svartisen Subglacial Laboratory, where tunnels melted in the ice provide temporary human access to the bed of Engabreen, a temperate outlet glacier of the Svartisen Ice Cap in Norway. A trough (2 m x 1.5 m x 0.5 m deep) was blasted in the rock bed, where the glacier is 220 m thick and sliding at 0.1-0.2 m/d. During two spring field seasons, this trough was filled with 2.5 tons of simulated till. Instruments in the till recorded shear (tiltmeters), volume change, total normal stress, and pore-water pressure as ice moved across the till surface. Pore pressure was brought to near the total normal stress by feeding water to the base of the till with a high-pressure pump, operated in a rock tunnel 4 m below the bed surface. Results illustrate some fundamental aspects of bed deformation. Permanent shear deformation requires low effective normal stress and hence high pore-water pressure, owing to the frictional nature of till. Shear strain generally increases upward in the bed toward the glacier sole, consistent with previous measurements beneath thinner ice at glacier margins. At low effective normal stresses, ice sometimes decouples from underlying till. Overall, bed deformation accounts for 10-35 % of basal motion, although this range excludes shear in the uppermost 0.05 m of till where shear was not measured. Pump tests with durations ranging from seconds to hours highlight the need

Influence of nitrogen fertilization and green manure on the economic feasibility of no-tilled wheat in the Cerrado

Directory of Open Access Journals (Sweden)

Douglas de Castilho Gitti

2012-04-01

Full Text Available The search for higher profitability in wheat crop with cost reduction technologies that may promote sustainability is an important matter in Brazilian agriculture. This study evaluated the profitability of no-tilled wheat, reducing nitrogen topdressing doses with the cultivation of green manure before the wheat crop. The experiment was carried out in Selvíria (MS, Brazil, in 2009/10. The experiment was arranged in a randomized block design with 36 treatments in splitplots and four replicates. The plots were formed by six types of green manure: Cajanus cajan L. BRS Mandarin, Crotalaria juncea L., Pennisetum americanum L. BRS 1501, fallow area and mixed cropping of Pennisetum americanum L. + Cajanus cajan L. and Pennisetum americanum L. + crotalaria which provided straw for no-tilled wheat in the winter, following the rice crop in the summer. The subplots were formed by six levels of topdressing nitrogen (0, 25, 50, 75, 100 and 125 kg N ha-1 using urea as a nitrogen source. The wheat grown after green manure in the previous winter crop, with no nitrogen topdressing and a rate of 25 kg ha-1 N, had more frequently production costs above the gross income. Wheat production cost after the mixed cropping Pennisetum americanum L. + Cajanus cajan L. and Pennisetum americanum L. + Crotalaria juncea L. from the previous winter crop, combined with nitrogen rates of 50 and 75 kg N ha-1, provided better profitability compared with the other green manures evaluated.

Implications of basal micro-earthquakes and tremor for ice stream mechanics: Stick-slip basal sliding and till erosion

Science.gov (United States)

Barcheck, C. Grace; Tulaczyk, Slawek; Schwartz, Susan Y.; Walter, Jacob I.; Winberry, J. Paul

2018-03-01

The Whillans Ice Plain (WIP) is unique among Antarctic ice streams because it moves by stick-slip. The conditions allowing stick-slip and its importance in controlling ice dynamics remain uncertain. Local basal seismicity previously observed during unstable slip is a clue to the mechanism of ice stream stick-slip and a window into current basal conditions, but the spatial extent and importance of this basal seismicity are unknown. We analyze data from a 2010-2011 ice-plain-wide seismic and GPS network to show that basal micro-seismicity correlates with large-scale patterns in ice stream slip behavior: Basal seismicity is common where the ice moves the least between unstable slip events, with small discrete basal micro-earthquakes happening within 10s of km of the central stick-slip nucleation area and emergent basal tremor occurring downstream of this area. Basal seismicity is largely absent in surrounding areas, where inter-slip creep rates are high. The large seismically active area suggests that a frictional sliding law that can accommodate stick-slip may be appropriate for ice stream beds on regional scales. Variability in seismic behavior over inter-station distances of 1-10 km indicates heterogeneity in local bed conditions and frictional complexity. WIP unstable slips may nucleate when stick-slip basal earthquake patches fail over a large area. We present a conceptual model in which basal seismicity results from slip-weakening frictional failure of over-consolidated till as it is eroded and mobilized into deforming till.

The determinants of intermediaries’ power over farmers’ margin-related activities

DEFF Research Database (Denmark)

Xhoxhi, Orjon; Pedersen, Søren Marcus; Lind, Kim Martin Hjorth

2014-01-01

This paper investigates the determinants of intermediaries’ power over farmers’ margin-related activities in Adana, Turkey. In doing so, a holistic model of intermediaries’ power over farmers’ margin-related activities is proposed. The objective of this model is to contribute to a better understa......This paper investigates the determinants of intermediaries’ power over farmers’ margin-related activities in Adana, Turkey. In doing so, a holistic model of intermediaries’ power over farmers’ margin-related activities is proposed. The objective of this model is to contribute to a better...

Volcanic passive margins: another way to break up continents.

Science.gov (United States)

Geoffroy, L; Burov, E B; Werner, P

2015-10-07

Two major types of passive margins are recognized, i.e. volcanic and non-volcanic, without proposing distinctive mechanisms for their formation. Volcanic passive margins are associated with the extrusion and intrusion of large volumes of magma, predominantly mafic, and represent distinctive features of Larges Igneous Provinces, in which regional fissural volcanism predates localized syn-magmatic break-up of the lithosphere. In contrast with non-volcanic margins, continentward-dipping detachment faults accommodate crustal necking at both conjugate volcanic margins. These faults root on a two-layer deformed ductile crust that appears to be partly of igneous nature. This lower crust is exhumed up to the bottom of the syn-extension extrusives at the outer parts of the margin. Our numerical modelling suggests that strengthening of deep continental crust during early magmatic stages provokes a divergent flow of the ductile lithosphere away from a central continental block, which becomes thinner with time due to the flow-induced mechanical erosion acting at its base. Crustal-scale faults dipping continentward are rooted over this flowing material, thus isolating micro-continents within the future oceanic domain. Pure-shear type deformation affects the bulk lithosphere at VPMs until continental breakup, and the geometry of the margin is closely related to the dynamics of an active and melting mantle.

Preoperative imaging and surgical margins in maxillectomy patients

NARCIS (Netherlands)

Kreeft, Anne Marijn; Smeele, Ludwig E.; Rasch, Coen R. N.; Hauptmann, Michael; Rietveld, Derk H. F.; Leemans, C. René; Balm, Alfons J. M.

2012-01-01

Background High rates of positive surgical margins are reported after a maxillectomy. A large part of tumors that are preoperatively considered operable can thus not be resected with tumor-free margins. Methods This was a retrospective study on medical files of 69 patients that underwent

Effect of post-implant edema on prostate brachytherapy treatment margins

International Nuclear Information System (INIS)

Reed, Daniel R.; Wallner, Kent; Ford, Eric; Mueller, Amy; Merrick, Gregory; Maki, Jeffrey; Sutlief, Steven; Butler, Wayne

2005-01-01

Purpose: To determine if postimplant prostate brachytherapy treatment margins calculated on Day 0 differ substantially from those calculated on Day 30. Methods: Thirty patients with 1997 American Joint Commission on Cancer clinical stage T1-T2 prostatic carcinoma underwent prostate brachytherapy with I-125 prescribed to 144 Gy. Treatment planning methods included using loose seeds in a modified peripheral loading pattern and treatment margins (TMs) of 5-8 mm. Postimplant plain radiographs, computed tomography scans, and magnetic resonance scans were obtained 1-4 hours after implantation (Day 0). A second set of imaging studies was obtained at 30 days after implantation (Day 30) and similarly analyzed. Treatment margins were measured as the radial distance in millimeters from the prostate edge to the 100% isodose line. The TMs were measured and tabulated at 90 o intervals around the prostate periphery at 0.6-cm intervals. Each direction was averaged to obtain the mean anterior, posterior, left, and right margins. Results: The mean overall TM increased from 2.6 mm (±2.3) on Day 0 to 3.5 mm (±2.4) on Day 30. The mean anterior margin increased from 1.2 mm on Day 0 to 1.8 mm on Day 30. The posterior margin increased from 1.2 mm on Day 0 to 2.8 mm on Day 30. The lateral treatment margins increased most over time, with mean right treatment margin increasing from 3.9 mm on Day 0 to 4.7 mm on Day 30. Conclusion: Treatment margins appear to be durable in the postimplant period, with a clinically insignificant increase from Day 0 to Day 30

STUDI PERBANDINGAN ANTARA ALGORITMA BIVARIATE MARGINAL DISTRIBUTION DENGAN ALGORITMA GENETIKA

Directory of Open Access Journals (Sweden)

Chastine Fatichah

2006-01-01

Full Text Available Bivariate Marginal Distribution Algorithm is extended from Estimation of Distribution Algorithm. This heuristic algorithm proposes the new approach for recombination of generate new individual that without crossover and mutation process such as genetic algorithm. Bivariate Marginal Distribution Algorithm uses connectivity variable the pair gene for recombination of generate new individual. Connectivity between variable is doing along optimization process. In this research, genetic algorithm performance with one point crossover is compared with Bivariate Marginal Distribution Algorithm performance in case Onemax, De Jong F2 function, and Traveling Salesman Problem. In this research, experimental results have shown performance the both algorithm is dependence of parameter respectively and also population size that used. For Onemax case with size small problem, Genetic Algorithm perform better with small number of iteration and more fast for get optimum result. However, Bivariate Marginal Distribution Algorithm perform better of result optimization for case Onemax with huge size problem. For De Jong F2 function, Genetic Algorithm perform better from Bivariate Marginal Distribution Algorithm of a number of iteration and time. For case Traveling Salesman Problem, Bivariate Marginal Distribution Algorithm have shown perform better from Genetic Algorithm of optimization result. Abstract in Bahasa Indonesia : Bivariate Marginal Distribution Algorithm merupakan perkembangan lebih lanjut dari Estimation of Distribution Algorithm. Algoritma heuristik ini mengenalkan pendekatan baru dalam melakukan rekombinasi untuk membentuk individu baru, yaitu tidak menggunakan proses crossover dan mutasi seperti pada Genetic Algorithm. Bivariate Marginal Distribution Algorithm menggunakan keterkaitan pasangan variabel dalam melakukan rekombinasi untuk membentuk individu baru. Keterkaitan antar variabel tersebut ditemukan selama proses optimasi berlangsung. Aplikasi yang

Consideration of margins for hypo fractionated radiotherapy

International Nuclear Information System (INIS)

Herschtal, A.; Foroudi, F.; Kron, T.

2010-01-01

Full text: Geographical misses of the tumour are of concern in radiotherapy and are typically accommodated by introducing margins around the target. However, there is a trade-off between ensuring the target receives sufficient dose and minimising the dose to surrounding normal structures. Several methods of determining margin width have been developed with the most commonly used one proposed by M. VanHerk (VanHerk UROBP 52: 1407, 2002). VanHerk's model sets margins to achieve 95% of dose coverage for the target in 90% of patients. However, this model was derived assuming an infinite number of fractions. The aim of the present work is to estimate the modifications necessary to the model if a finite number of fractions are given. Software simulations were used to determine the true probability of a patient achieving 95% target coverage if different fraction numbers are used for a given margin width. Model parameters were informed by a large data set recently acquired at our institution using daily image guidance for prostate cancer patients with implanted fiducial markers. Assuming a 3 mm penumbral width it was found that using the VanHerk model only 74 or 54% of patients receive 95% of the prescription dose if 20 or 6 fractions are given, respectively. The steep dose gradients afforded by IMRT are likely to make consideration of the effects of hypofractionation more important. It is necessary to increase the margins around the target to ensure adequate tumour coverage if hypofractionated radiotherapy is to be used for cancer treatment. (author)

Influence of Different Ceramic Systems on Marginal Misfit.

Science.gov (United States)

Vargas, S P; Neves, A C C; Vitti, R; Amaral, M; Henrique, M N; Silva-Concílio, L R

2017-09-01

the aim of this study was to evaluate the marginal misfit at the interface between a ceramic coping and its abutment. Twenty-four specimens were made with solid abutments. The specimens were divided into 3 groups according to the ceramic system (n = 8): Lava (zirconia), IPS e.max Press (lithium disilicate), and IPS Empress Esthetic (leucite). All copings were cemented with resin luting agent (RelyX U200) and the marginal misfit were evaluated at 3 different times: initial, after cementation, and after mechanical cycling using a linear measuring microscope (Measuring Microscope STM-Olympus) at a magnification of 40x. All specimens were subjected to mechanical cycling (1 million cycles) by an universal testing machine (Instron 8800). The results were statistically analyzed using Analysis of Variance and Student's t-test (α = 0.05). all groups showed an increase in the marginal misfit after cementation. The lithium disilicate group demonstrated the lowest interacial gap values at each evaluation (p = 0.001). The zirconia and leucite groups showed similar interfacial gap values (initial, p = 0.244; and post cementation, p = 0.751). the cementation increase the marginal misfit, but the mechanical cycling did not influence the marginal misfit of the ceramics systems evaluated. Copyright© 2017 Dennis Barber Ltd.

Determinants of banks’ net interest margins in Central and Eastern Europe

Directory of Open Access Journals (Sweden)

Tomislav Rizdak

2013-03-01

Full Text Available This research analyzes the main determinants of the net interest margin of banks operating in Central and Eastern European (CEE countries in the period from 1999 to 2010. The results reveal several main drivers of net interest margins in the CEE. Prior to 2008 the net interest margins declined primarily due to strong capital inflows and stable macroeconomic environment. In the crisis period, significant rise in government debt accompanied by the increase in macroeconomic risks and abating capital inflows were pushing margins up while other factors such as low credit demand, higher capitalization and significantly increased share of non-performing loans pressured banks’ margins down. The results also confirm the important contribution of higher efficiency to lowering banks’ margins.

Marginal Assessment of Crowns by the Aid of Parallel Radiography

Directory of Open Access Journals (Sweden)

Farnaz Fattahi

2015-03-01

Full Text Available Introduction: Marginal adaptation is the most critical item in long-term prognosis of single crowns. This study aimed to assess the marginal quality as well asthe discrepancies in marginal integrity of some PFM single crowns of posterior teeth by employing parallel radiography in Shiraz Dental School, Shiraz, Iran. Methods: In this descriptive study, parallel radiographies were taken from 200 fabricated PFM single crowns of posterior teeth after cementation and before discharging the patient. To calculate the magnification of the images, a metallic sphere with the thickness of 4 mm was placed in the direction of the crown margin on the occlusal surface. Thereafter, the horizontal and vertical space between the crown margins, the margin of preparations and also the vertical space between the crown margin and the bone crest were measured by using digital radiological software. Results: Analysis of data by descriptive statistics revealed that 75.5% and 60% of the cases had more than the acceptable space (50µm in the vertical (130±20µm and horizontal (90±15µm dimensions, respectively. Moreover, 85% of patients were found to have either horizontal or vertical gap. In 77% of cases, the margins of crowns invaded the biologic width in the mesial and 70% in distal surfaces. Conclusion: Parallel radiography can be expedient in the stage of framework try-in to yield some important information that cannot be obtained by routine clinical evaluations and may improve the treatment prognosis

Supervised linear dimensionality reduction with robust margins for object recognition

Science.gov (United States)

Dornaika, F.; Assoum, A.

2013-01-01

Linear Dimensionality Reduction (LDR) techniques have been increasingly important in computer vision and pattern recognition since they permit a relatively simple mapping of data onto a lower dimensional subspace, leading to simple and computationally efficient classification strategies. Recently, many linear discriminant methods have been developed in order to reduce the dimensionality of visual data and to enhance the discrimination between different groups or classes. Many existing linear embedding techniques relied on the use of local margins in order to get a good discrimination performance. However, dealing with outliers and within-class diversity has not been addressed by margin-based embedding method. In this paper, we explored the use of different margin-based linear embedding methods. More precisely, we propose to use the concepts of Median miss and Median hit for building robust margin-based criteria. Based on such margins, we seek the projection directions (linear embedding) such that the sum of local margins is maximized. Our proposed approach has been applied to the problem of appearance-based face recognition. Experiments performed on four public face databases show that the proposed approach can give better generalization performance than the classic Average Neighborhood Margin Maximization (ANMM). Moreover, thanks to the use of robust margins, the proposed method down-grades gracefully when label outliers contaminate the training data set. In particular, we show that the concept of Median hit was crucial in order to get robust performance in the presence of outliers.

Influence of margin segmentation and anomalous volcanism upon the break-up of the Hatton Bank rifted margin, west of the UK

Science.gov (United States)

Elliott, G. M.; Parson, L. M.

2007-12-01

The Hatton Bank margin, flanking the Iceland Basin is a widely cited example of a volcanic rifted margin. Prior to this study insights into the break-up history of the margin have been limited to profiles in the north and south, yet whilst valuable, the along margin tectono-magmatic variability has not been revealed. Over 5660 line km of high quality reflection seismic profiles with supplementary multibeam bathymetry were collected to support the UK's claim to Hatton region under the United Nations Convention on Law of the Sea (UNCLOS). Integration of this new data with existing profiles, allowed the margin to be divided into three segments, each of which are flanked by oceanic crust with a smooth upper surface and internal dipping reflectors. The southernmost segment is characterised by a series of inner and outer seaward dipping reflector (SDR) packages, which are separated by an outer high feature. The outer SDR are truncated by Endymion Spur, a chain of steep sided, late stage volcanic cones linked with necks. The central sector has no inner SDR package and is characterised by the presence of a highly intruded continental block, the Hatton Bank Block (HBB). The northern sector is adjacent to Lousy Bank, with a wider region of SDR recognised than to the south and a high amount of volcanic cones imaged. The variations in the distribution of the SDR's along the margin, the presence of the HBB and Endymion Spur all suggest that the break-up process was not uniform alongstrike. The division of the margin into three sectors reveals that structural segmentation played an important role in producing the variations along the margin. Break- up initiated in the south and progressed north producing the SDR packages witnessed, when the HBB was encountered the focus of break-up moved seaward of the block. The northern sector was closer to the Iceland Hotspot and hence a greater amount of volcanism is encountered. The smooth oceanic basement also indicates a high thermal flux

Slope failure of chalk channel margins

DEFF Research Database (Denmark)

Gale, A.; Anderskouv, Kresten; Surlyk, Finn

2015-01-01

provide evidence for recurring margin collapse of a long-lived Campanian channel. Compressionally deformed and thrust chalk hardgrounds are correlated to thicker, non-cemented chalk beds that form a broad, gentle anticline. These chalks represent a slump complex with a roll-over anticline of expanded, non......-cemented chalk in the head region and a culmination of condensed hardgrounds in the toe region. Observations strongly suggest that the slumping represents collapse of a channel margin. Farther northwards, the contemporaneous succession shows evidence of small-scale penecontemporaneous normal faulting towards...

Perennial Grass Bioenergy Cropping on Wet Marginal Land

NARCIS (Netherlands)

Das, Srabani; Teuffer, Karin; Stoof, Cathelijne R.; Walter, Michael F.; Walter, M.T.; Steenhuis, Tammo S.; Richards, Brian K.

2018-01-01

The control of soil moisture, vegetation type, and prior land use on soil health parameters of perennial grass cropping systems on marginal lands is not well known. A fallow wetness-prone marginal site in New York (USA) was converted to perennial grass bioenergy feedstock production. Quadruplicate

Helping Students on the Margin Succeed in Schools.

Science.gov (United States)

Langenfeld, Michelle Schoen; Cumming, Brenda

1996-01-01

Addresses how Apple Valley High School (Minnesota) has been able to help marginal students succeed in school. The fundamental actions that contributed to the effectiveness of study-team efforts to help marginal students are discussed, and what has been learned through these efforts is considered. (GR)

Hymenobacter arcticus sp. nov., isolated from glacial till.

Science.gov (United States)

Chang, Xulu; Zheng, Jiangli; Jiang, Fan; Liu, Ping; Kan, Wenjing; Qu, Zhihao; Fang, Chengxiang; Peng, Fang

2014-06-01

A novel, red-pink-pigmented strain, designated R2-4(T), was isolated from a till sample near Ny-Alesund, Svalbard Archipelago, Norway. Cells were aerobic, Gram-stain-negative and rod-shaped. Growth occurred at 4-30 °C (optimum, 20-22 °C), at pH 6.0-9.0 (optimum, pH 7.0) and with 0-1% NaCl added to R2A agar. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain R2-4(T) belonged to the genus Hymenobacter. 16S rRNA gene sequence similarity between strain R2-4(T) and the type strains of related species of the genus ranged from 94.51 to 96.05%. Strain R2-4(T) contained iso-C(15 : 0), anteiso-C(15 : 0), summed feature 3 (C(16 : 1)ω6c and/or C(16 : 1)ω7c), summed feature 4 (C(17 : 1) anteiso B and/or iso I) and C(16 : 1)ω5c as the major cellular fatty acids, MK-7 as the major respiratory quinone, and phosphatidylethanolamine, unknown aminophospholipids, unknown aminolipids and unknown lipids as the main polar lipids. The polyamine was sym-homospermidine. The DNA G+C content of strain R2-4(T) was 61.6 mol%. On the basis of phylogenetic, physiological and chemotaxonomic data, strain R2-4(T) is considered to represent a novel species of the genus Hymenobacter, for which the name Hymenobacter arcticus sp. nov. is proposed. The type strain is R2-4(T) ( = CCTCC AB 2012104(T) = KACC 16881(T)). © 2014 IUMS.

Principals' Perceived Supervisory Behaviors Regarding Marginal Teachers in Two States

Science.gov (United States)

Range, Bret; Hewitt, Paul; Young, Suzie

2014-01-01

This descriptive study used an online survey to determine how principals in two states viewed the supervision of marginal teachers. Principals ranked their own evaluation of the teacher as the most important factor when identifying marginal teachers and relied on informal methods to diagnose marginal teaching. Female principals rated a majority of…

Quantifying Safety Margin Using the Risk-Informed Safety Margin Characterization (RISMC)

Energy Technology Data Exchange (ETDEWEB)

Grabaskas, David; Bucknor, Matthew; Brunett, Acacia; Nakayama, Marvin

2015-04-26

The Risk-Informed Safety Margin Characterization (RISMC), developed by Idaho National Laboratory as part of the Light-Water Reactor Sustainability Project, utilizes a probabilistic safety margin comparison between a load and capacity distribution, rather than a deterministic comparison between two values, as is usually done in best-estimate plus uncertainty analyses. The goal is to determine the failure probability, or in other words, the probability of the system load equaling or exceeding the system capacity. While this method has been used in pilot studies, there has been little work conducted investigating the statistical significance of the resulting failure probability. In particular, it is difficult to determine how many simulations are necessary to properly characterize the failure probability. This work uses classical (frequentist) statistics and confidence intervals to examine the impact in statistical accuracy when the number of simulations is varied. Two methods are proposed to establish confidence intervals related to the failure probability established using a RISMC analysis. The confidence interval provides information about the statistical accuracy of the method utilized to explore the uncertainty space, and offers a quantitative method to gauge the increase in statistical accuracy due to performing additional simulations.

Development and function of the splenic marginal zone

NARCIS (Netherlands)

Mebius, Reina E.; Nolte, Martijn A.; Kraal, Georg

2004-01-01

The marginal zone of the spleen is a crucial region where blood-borne pathogens are sequestered by macrophages with unique arrays of scavenger molecules. In addition, a special population of B cells, which is capable of rapid activation, resides in this region. Marginal zone B cells and macrophages

Marginal Leakage of Class V Composite Resin Restorations

Directory of Open Access Journals (Sweden)

Maryam Khoroushi

2018-01-01

Full Text Available >Introduction: Marginal leakage is one of the significant causes of restoration failure. This in-vitro study was conducted to compare cone beam computed tomography (CBCT and dye-penetration methods for determining marginal leakage at gingival surface of class V resin composite restorations.Materials and Methods: Class V cavities were prepared on the buccal surfaces of nineteen caries-free extracted human molar teeth. Cavities were conditioned and filled. The teeth were immersed in a 50% w/w aqueous silver nitrate solution for 24 h and were taken out and rinsed with distilled water. Then, they were put into a developing solution. Whole specimens were first viewed with CBCT and were then sectioned and evaluated by stereomicroscope.Results: Measurement of agreement between CBCT and stereomicroscope revealed that 15 (78.9% teeth had score 0, 1 (5.3% tooth had score 1, and 1 (5.3% tooth had score 2 in both techniques. Measurement of agreement between CBCT and stereomicroscope techniques, in the detection of marginal leakage, was 89.5% (Kappa coefficient = 0.627, P = 0.00. The Wilcoxon paired rank test revealed no significant difference between the results of CBCT and stereomicroscope in measuring the leakage at gingival margin (P = 0.157.Conclusion: Considering the limitations of the study, there was no significant difference between the results of CBCT and stereomicroscope in measuring the leakage at gingival margin of class V composite restorations. CBCT can be used noninvasively to detect the marginal leakage of gingival wall of class V composite restorations using aqueous silver nitrate solution as a tracer.

Integrated Characterization of DNAPL Source Zone Architecture in Clay Till and Limestone Bedrock

DEFF Research Database (Denmark)

Broholm, Mette Martina; Janniche, Gry Sander; Fjordbøge, Annika Sidelmann

2014-01-01

Background/Objectives. Characterization of dense non-aqueous phase liquid (DNAPL) source zone architecture is essential to develop accurate site specific conceptual models, delineate and quantify contaminant mass, perform risk assessment, and select and design remediation alternatives. The activi......Background/Objectives. Characterization of dense non-aqueous phase liquid (DNAPL) source zone architecture is essential to develop accurate site specific conceptual models, delineate and quantify contaminant mass, perform risk assessment, and select and design remediation alternatives...... innovative investigation methods and characterize the source zone hydrogeology and contamination to obtain an improved conceptual understanding of DNAPL source zone architecture in clay till and bryozoan limestone bedrock. Approach/Activities. A wide range of innovative and current site investigative tools...... for direct and indirect documentation and/or evaluation of DNAPL presence were combined in a multiple lines of evidence approach. Results/Lessons Learned. Though no single technique was sufficient for characterization of DNAPL source zone architecture, the combined use of membrane interphase probing (MIP...

Marginally Deformed Starobinsky Gravity

DEFF Research Database (Denmark)

Codello, A.; Joergensen, J.; Sannino, Francesco

2015-01-01

We show that quantum-induced marginal deformations of the Starobinsky gravitational action of the form $R^{2(1 -\\alpha)}$, with $R$ the Ricci scalar and $\\alpha$ a positive parameter, smaller than one half, can account for the recent experimental observations by BICEP2 of primordial tensor modes....

Komorbiditet ved marginal parodontitis

DEFF Research Database (Denmark)

Holmstrup, Palle; Damgaard, Christian; Olsen, Ingar

2017-01-01

Nærværende artikel præsenterer en oversigt over den foreliggende væsentligste viden om sammenhængen mellem marginal parodontitis og en række medicinske sygdomme, herunder hjerte-kar-sygdomme, diabetes mellitus, reumatoid arthritis, osteoporose, Parkinsons sygdom, Alzheimers sygdom, psoriasis og...

From marginality to further marginalization: Experiences from the victims of the July 2000 Payatas trashslide in the Philippines

Directory of Open Access Journals (Sweden)

JC Gaillard

2009-04-01

Full Text Available Victims of disasters are disproportionately drawn from the marginalized segments of society. Disaster victims are marginalized geographically because they live in hazardous places, socially because they are members of minority groups, economically because they are poor, and marginalized politically because their voice is disregarded by those with political power. #e victims of the July 2000 Payatas trash slide in the Philippines show all these characteristics. Most of the victims of the disaster were urban migrants who came all the way from their poor provinces to settle on the lower slopes of the largest dumpsite of the country. #ey scavenged recyclable materials to sell as a way to make a living, but their limited incomes did not allow them to a$ord safer locations for their homes, farther removed from the slopes of the dumpsite. On the morning of 10 July 2000, 300 of them lost their lives when a large section of the dumpsite collapsed in a massive debris %ow which buried their houses. In the aftermath of the disaster, the survivors who used to live on the dumpsite, and who were the poorest victims, were also those who were relocated by the Philippine government. In the present case, the most vulnerable families in the face of the trash slide were eventually those who had to su#er again from life-disrupting relocation while being the less able to recover quickly from the disaster. Daily incomes of relocated families are today much lower than those who remained in the vicinity of the dumpsite. For the victims of the July 2000 Payatas tragedy, poverty thus acted as a vicious, worsening circle which ranged from vulnerability to poor recovery, or from marginality to further marginalization.

Intraoperative monitoring of marginal mandibular nerve during neck dissection.

Science.gov (United States)

Tirelli, Giancarlo; Bergamini, Pier Riccardo; Scardoni, Alessandro; Gatto, Annalisa; Boscolo Nata, Francesca; Marcuzzo, Alberto Vito

2018-05-01

The purpose of this study was to assess the efficacy of intraoperative nerve integrity monitoring (NIM) to prevent marginal mandibular nerve injuries during neck dissection. This prospective study compared 36 patients undergoing NIM-assisted neck dissection from July 2014 to March 2015 to a cohort of 35 patients subjected to neck dissection over an identical period of time before the technique was introduced. We also assessed possible correlations between marginal mandibular nerve injuries and other factors, such as anthropometric measurements, presence of clinical neck metastases, type of neck dissection, and site of primary tumor. The incidence of marginal mandibular nerve paralyses was significantly lower among the group of patients undergoing NIM-assisted neck dissection (P = .021). There was no significant difference in the duration of the procedure, and the technique resulted in a limited increase of cost. No other factor seemed to influence the onset of marginal mandibular nerve palsy. In our opinion, NIM is a valuable aid for preventing marginal mandibular nerve injuries during neck dissection. © 2018 Wiley Periodicals, Inc.

Radiotherapy Results of Carcinoma of Cervix with positive Resection Margin

International Nuclear Information System (INIS)

Huh, Seung Jae; Kim, Dae Yong; Ahn, Yong Chan; Kim, Won Dong; Wu, Hong Gyun; Ha, Sung Whan; Kim, Il Han; Park, Charn Il

1996-01-01

Purpose : Patients with cervical cancer who have positive resection margins after radical hysterectomy are at increased risk for local recurrence. The results of postoperative pelvic radiotherapy for cervix cancer with positive resection margins were analyzed to evaluated the role of radiotherapy. Materials and Methods : Between 1979 and 1992, 60 patients of cervix carcinoma were treated with postoperative radiotherapy after radical hysterectomy because of positive vaginal(48 patients) or parametrial resection margins(12 patients). Patients were treated with external beam radiation therapy(EBRT) alone (12 patients) or EBRT plus vaginal ovoid irradiation (VOI) (48 patients). The median follow-up period was 5 months. Results : The 5-year actuarial disease free and overall survival rates for all patients were 75.2%, 84.1%, respectively. The overall recurrence rate was 23%(14/60). In 48 patients with positive vaginal resection margins, the pelvic recurrence was 8%(4/48). Distant metastasis was 15%(7/48). Of the 43 patients with positive vaginal resection margins treated with EBRT and VOI, recurrence rate was 21%(9/43), while recurrence rate was 40%(2/5) in the EBRT only treated group. In 12 patients with positive parametrial margins, three patients (25%) had distant metastases. The most significant prognostic factor was lymph node metastasis. Complications resulting from radiotherapy occurred at a rate of 32%(19/60) and grade III complications occurred in three patients (5%). Conclusion : Postoperative radiotherapy can produce excellent pelvic control rates in patients with positive resection margins. In patients with positive vaginal margins, whole pelvic EBRT and BOI is recommended

Marginal pricing of transmission services: An analysis of cost recovery

Energy Technology Data Exchange (ETDEWEB)

Perez-Arriaga, I.J.; Rubio, F.J. [Univ. Pontificia Comillas, Madrid (Spain); Puerta, J.F.; Arceluz, J.; Marin, J. [IBERDROLA, Bilbao (Spain). Unidad de Planificacion Estrategica

1995-02-01

This paper presents an in-depth analysis of network revenues computed with marginal pricing, and in particular it investigates the reasons why marginal prices fail to recover the total incurred network costs in actual power systems. The basic theoretical results are presented and the major causes of the mismatch between network costs and marginal revenues are identified and illustrated with numerical examples, some tutorial and others of realistic size. The regulatory implications of marginal network pricing in the context of competitive electricity markets are analyzed, and suggestions are provided for the meaningful allocation of the costs of the network among its users.

Marginal pricing of transmission services: An analysis of cost recovery

International Nuclear Information System (INIS)

Perez-Arriaga, I.J.; Rubio, F.J.; Puerta, J.F.; Arceluz, J.; Marin, J.

1995-01-01

This paper presents an in-depth analysis of network revenues computed with marginal pricing, and in particular it investigates the reasons why marginal prices fail to recover the total incurred network costs in actual power systems. The basic theoretical results are presented and the major causes of the mismatch between network costs and marginal revenues are identified and illustrated with numerical examples, some tutorial and others of realistic size. The regulatory implications of marginal network pricing in the context of competitive electricity markets are analyzed, and suggestions are provided for the meaningful allocation of the costs of the network among its users

Evaluation of the marginal fit of metal copings fabricated on three different marginal designs using conventional and accelerated casting techniques: an in vitro study.

Science.gov (United States)

Vaidya, Sharad; Parkash, Hari; Bhargava, Akshay; Gupta, Sharad

2014-01-01

Abundant resources and techniques have been used for complete coverage crown fabrication. Conventional investing and casting procedures for phosphate-bonded investments require a 2- to 4-h procedure before completion. Accelerated casting techniques have been used, but may not result in castings with matching marginal accuracy. The study measured the marginal gap and determined the clinical acceptability of single cast copings invested in a phosphate-bonded investment with the use of conventional and accelerated methods. One hundred and twenty cast coping samples were fabricated using conventional and accelerated methods, with three finish lines: Chamfer, shoulder and shoulder with bevel. Sixty copings were prepared with each technique. Each coping was examined with a stereomicroscope at four predetermined sites and measurements of marginal gaps were documented for each. A master chart was prepared for all the data and was analyzed using Statistical Package for the Social Sciences version. Evidence of marginal gap was then evaluated by t-test. Analysis of variance and Post-hoc analysis were used to compare two groups as well as to make comparisons between three subgroups . Measurements recorded showed no statistically significant difference between conventional and accelerated groups. Among the three marginal designs studied, shoulder with bevel showed the best marginal fit with conventional as well as accelerated casting techniques. Accelerated casting technique could be a vital alternative to the time-consuming conventional casting technique. The marginal fit between the two casting techniques showed no statistical difference.

Systems considerations in seismic margin evaluations

International Nuclear Information System (INIS)

Buttermer, D.R.

1987-01-01

Increasing knowledge in the geoscience field has led to the understanding that, although highly unlikely, it is possible for a nuclear power plant to be subjected to earthquake ground motion greater than that for which the plant was designed. While it is recognized that there are conservatisms inherent in current design practices, interest has developed in evaluating the seismic risk of operating plants. Several plant-specific seismic probabilistic risk assessments (SPRA) have been completed to address questions related to the seismic risk of a plant. The results from such SPRAs are quite informative, but such studies may entail a considerable amount of expensive analysis of large portions of the plant. As an alternative to an SPRA, it may be more practical to select an earthquake level above the design basis for which plant survivability is to be demonstrated. The principal question to be addressed in a seismic margin evaluation is: At what ground motion levels does one have a high confidence that the probability of seismically induced core damage is sufficiently low? In a seismic margin evaluation, an earthquake level is selected (based on site-specific geoscience considerations) for which a stable, long-term safe shutdown condition is to be demonstrated. This prespecified earthquake level is commonly referred to as the seismic margin earthquake (SME). The Electric Power Research Institute is currently supporting a research project to develop procedures for use by the utilities to allow them to perform nuclear plant seismic margin evaluations. This paper describes the systems-related aspects of these procedures

Radiotherapy margin design with particular consideration of high curvature CTVs

International Nuclear Information System (INIS)

Herschtal, Alan; Kron, Tomas; Fox, Chris

2009-01-01

In applying 3D conformal radiation therapy to a tumor clinical target volume (CTV), a margin is added around the CTV to account for any sources of error in the application of treatment which may result in misalignment between the CTV and the dose distribution actually delivered. The volume enclosed within the CTV plus the margin is known as the PTV, or planning target volume. The larger the errors are anticipated to be, the wider the margin will need to be to accommodate those errors. Based on the approach of van Herk et al. [''The probability of correct target dosage: Dose-population histograms for deriving treatment margins in radiotherapy,'' Int. J. Radiat. Oncol. Biol., Phys. 47(4), 1121-1135 (2000)] this paper develops the mathematical theory behind the calculation of the margin width required to ensure that the entire CTV receives sufficiently high dose with sufficiently high probability. The margin recipe developed not only considers the magnitude of the errors but also includes a term to adjust for curved CTV surfaces. In doing so, the accuracy of the margin recipe is enhanced yet remains mathematically concise enough to be readily implemented in the clinical setting. The results are particularly relevant for clinical situations in which the uncertainties in treatment are large relative to the size of the CTV.

Marginal Pricing and Student Investment in Higher Education

Science.gov (United States)

Hemelt, Steven W.; Stange, Kevin M.

2016-01-01

This paper examines the effect of marginal price on students' educational investments using rich administrative data on students at Michigan public universities. Marginal price refers to the amount colleges charge for each additional credit taken in a semester. Institutions differ in how they price credits above the full-time minimum (of 12…

Short-term marginal costs in French agriculture

OpenAIRE

Latruffe, Laure; LETORT, Elodie

2011-01-01

The paper investigates short-term marginal costs in French agriculture for field cropping, beef cattle, and dairy farms during the period 1995-2006. The multi-input multi-output Symmetric Generalised MacFadden cost function is used, with three variable inputs (crop-specific, animal-specific, energy costs), four outputs and three quasi-fixed inputs. Results indicate that marginal costs are on average lower for crop farms than for livestock samples. However, for crop farms, Common Agricultural ...

Are subduction zones invading the atlantic? Evidence from the southwest iberia margin

NARCIS (Netherlands)

Duarte, João C.; Rosas, Filipe M.; Terrinha, Pedro; Schellart, Wouter P.; Boutelier, David; Gutscher, Marc André; Ribeiro, António

Subduction initiation at passive margins plays a central role in the plate tectonics theory. However, the process by which a passive margin becomes active is not well understood. In this paper we use the southwest Iberia margin (SIM) in the Atlantic Ocean to study the process of passive margin

Deregulated model and locational marginal pricing

International Nuclear Information System (INIS)

Sood, Yog Raj; Padhy, N.P.; Gupta, H.O.

2007-01-01

This paper presents a generalized optimal model that dispatches the pool in combination with privately negotiated bilateral and multilateral contracts while maximizing social benefit has been proposed. This model determines the locational marginal pricing (LMP) based on marginal cost theory. It also determines the size of non-firm transactions as well as pool demand and generations. Both firms as well as non-firm transactions are considered in this model. The proposed model has been applied to IEEE-30 bus test system. In this test system different types of transactions are added for analysis of the proposed model. (author)

Long-term agroecosystem research in the Central Mississippi River Basin: hydrogeologic controls and crop management influence on nitrates in loess and fractured glacial till

Science.gov (United States)

Nitrogen (N) from agricultural activities has been suspected as a primary source of elevated ground water nitrate (NO3-N). The objective of this research was to assess the impact of common cropping systems on NO3-N levels for a glacial till aquifer underlying claypan soils in a predominantly agricul...

30 CFR 204.4 - What is a marginal property under this part?

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What is a marginal property under this part... REVENUE MANAGEMENT ALTERNATIVES FOR MARGINAL PROPERTIES General Provisions § 204.4 What is a marginal property under this part? (a) To qualify as a marginal property eligible for royalty prepayment or...

Systematic reviews: I. The correlation between laboratory tests on marginal quality and bond strength. II. The correlation between marginal quality and clinical outcome.

Science.gov (United States)

Heintze, Siegward D

2007-01-01

An accepted principle in restorative dentistry states that restorations should be placed with the best marginal quality possible to avoid postoperative sensitivity, marginal discoloration, and secondary caries. Different laboratory methods claim to predict the clinical performance of restorative materials, for example, tests of bond strength and microleakage and gap analysis. The purpose of this review was twofold: (1) find studies that correlated the results of bond strength tests with either microleakage or gap analysis for the same materials, and (2) find studies that correlated the results of microleakage and/or gaps with the clinical parameters for the same materials. Furthermore, influencing factors on the results of the laboratory tests were reviewed and assessed. For the first question, searches for studies were conducted in the MEDLINE database and IADR/AADR abtracts online with specific search and inclusion criteria. The outcome for each study was assessed on the basis of the statistical test applied in the study, and finally the number of studies with or without correlation was compiled. For the second question, results of the quantitative marginal analysis of Class V restorations published by the University of Zürich with the same test protocol and prospective clinical trials were searched that investigated the same materials for at least 2 years in Class V cavities. Pearson correlation coefficients were calculated for pooled data of materials and clinical outcome parameters such as retention loss, marginal discoloration, marginal integrity, and secondary caries. For the correlation of dye penetration and clinical outcome, studies on Class V restorations published by the same research institute were searched in MEDLINE that examined the same adhesive systems as the selected clinical trials. For the correlation bond strength/microleakage, 30 studies were included into the review, and for the correlation bond strength/gap analysis 18 studies. For both

Testing for marginal linear effects in quantile regression

KAUST Repository

Wang, Huixia Judy

2017-10-23

The paper develops a new marginal testing procedure to detect significant predictors that are associated with the conditional quantiles of a scalar response. The idea is to fit the marginal quantile regression on each predictor one at a time, and then to base the test on the t-statistics that are associated with the most predictive predictors. A resampling method is devised to calibrate this test statistic, which has non-regular limiting behaviour due to the selection of the most predictive variables. Asymptotic validity of the procedure is established in a general quantile regression setting in which the marginal quantile regression models can be misspecified. Even though a fixed dimension is assumed to derive the asymptotic results, the test proposed is applicable and computationally feasible for large dimensional predictors. The method is more flexible than existing marginal screening test methods based on mean regression and has the added advantage of being robust against outliers in the response. The approach is illustrated by using an application to a human immunodeficiency virus drug resistance data set.

Testing for marginal linear effects in quantile regression

KAUST Repository

Wang, Huixia Judy; McKeague, Ian W.; Qian, Min

2017-01-01

The paper develops a new marginal testing procedure to detect significant predictors that are associated with the conditional quantiles of a scalar response. The idea is to fit the marginal quantile regression on each predictor one at a time, and then to base the test on the t-statistics that are associated with the most predictive predictors. A resampling method is devised to calibrate this test statistic, which has non-regular limiting behaviour due to the selection of the most predictive variables. Asymptotic validity of the procedure is established in a general quantile regression setting in which the marginal quantile regression models can be misspecified. Even though a fixed dimension is assumed to derive the asymptotic results, the test proposed is applicable and computationally feasible for large dimensional predictors. The method is more flexible than existing marginal screening test methods based on mean regression and has the added advantage of being robust against outliers in the response. The approach is illustrated by using an application to a human immunodeficiency virus drug resistance data set.

Preface: Biogeochemistry–ecosystem interaction on changing continental margins in the Anthropocene

Digital Repository Service at National Institute of Oceanography (India)

Liu, K-K.; Emeis, K.-C.; Levin, L.A.; Naqvi, S.W.A.; Roman, M.

and hypercapnia in upwelling systems • Interactions between natural and social sciences for better steward- ship of continental margins. It has long been acknowledged (e.g., Doney, 2010; Liu et al., 2010) that marine ecosystems on continental margins, including... and possibly manage margin ecosystems in a changing world. Effective governance of social–ecological systems on continental margins is key to reducing the pervasive over- exploitation, depletion and destruction of marine resources and http://dx.doi.org/10...

Assessment of bioenergy potential on marginal land in China

Energy Technology Data Exchange (ETDEWEB)

Zhuang, Dafang; Jiang, Dong; Liu, Lei; Huang, Yaohuan [Data Center for Resources and Environmental Sciences, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, 11A Datun Road, Chaoyang District, Beijing 100101 (China)

2011-02-15

Bioenergy developed from energy plants will play a more and more important role in future energy supply. Much attention has been paid to energy plants in recent years. As China has fairly limited cultivated land resources, the bioenergy development may mainly rely on the exploitation of marginal land. This study focused on the assessment of marginal land resources and bio-fuel potential in China using newly acquired data and Geographic Information System (GIS) techniques. A multi-factor analysis method was adopted to identify marginal lands for bioenergy development in China, with data of several main types of energy plants on the eco-environmental requirements and natural habits employed. A combined planting zonation strategy was proposed, which was targeted for five species of energy plants including Helianthus tuberous L., Pistacia chinensis, Jatropha curcas L., Cassava and Vernicia fordii. The results indicated that total area of marginal land exploitable for development of energy plants on a large scale was about 43.75 million ha. If 10% of this marginal land was fully utilized for growing the energy plants, the production of bio-fuel would be 13.39 million tons. (author)

Relief for marginal wells is better than energy tax

International Nuclear Information System (INIS)

Swords, J.; Wilson, D.

1993-01-01

By increasing production costs and reducing petroleum prices, President Bill Clinton's proposed energy tax would increase marginal well abandonments and hasten the decline of the US oil and gas industry. Instead, the US needs tax law changes to help counteract the increasing number of oil and gas well abandonments in the lower 48 states. The proposed tax would create potential difficulties, while three incentives could be introduced to reduce abandonments and at the same time preserve US government tax revenues that otherwise would be lost. Eliminating the net income limitation on percentage depletion allowances on wells that would otherwise be abandoned would be a great help for marginal well operators. Extended enhanced oil recovery (EOR) credits and broader investment tax credits could also serve the dual purpose of keeping marginal wells operating longer and generating more federal tax revenues. A marginal well investment tax credit should be provided that is not just a credit for incremented investments that exceed investment in prior years. An investment tax credit based on out-of-pocket costs of production, targeted for marginal wells, would be an important incentive to invest in, and continue to maintain, these properties. (author)

In silico particle margination in blood flow

OpenAIRE

Müller, Kathrin

2015-01-01

A profound knowledge of margination, the migration of blood components to the vessel wall in blood flow, is required in order to understand the genesis of various diseases, as e.g., cardiovascular diseases or bleeding disorders. Margination of particles is a pre-condition for potential adhesion. Adhesion to the vessel wall is required for platelets, the protein von Willebrand factor (VWF), but also for drug and imaging agent carriers in order to perform their particular tasks. In the haemosta...

Seaward dipping reflectors along the SW continental margin of India: Evidence for volcanic passive margin

Digital Repository Service at National Institute of Oceanography (India)

Ajay, K.K.; Chaubey, A.K.; Krishna, K.S.; Rao, D.G.; Sar, D.

Multi-channel seismic reflection profiles across the southwest continental margin of India (SWCMI) show presence of westerly dipping seismic reflectors beneath sedimentary strata along the western flank of the Laccadive Ridge-northernmost part...

ORGANIC MATTER FRACTIONS OF AN IRRIGATED OXISOL UNDER NO - TILL AND CONVENTIONAL TILLAGE IN THE BRAZILIAN SEMI - ARID REGION

Directory of Open Access Journals (Sweden)

RAFAEL PEREIRA SALES

2017-01-01

Full Text Available The replacement of natural vegetation by crop systems directly impacts the soil organic matter fractions. The objective of this study was to evaluate the total organic carbon (TOC and nitrogen (TN contents in different fractions of the soil organic matter (SOM of an Oxisol of the Brazilian semiarid region under different irrigated crops and different soil management systems. Seven treatments were evaluated, which consisted of two soil management systems (no - till and conventional tillage and three crops (maize, sunflower and sorghum, using as reference the soil under a native forest (NF. The summer crops preceded common bean crops in the autumn - winter. The total organic carbon content, total nitrogen, carbon content in humic substances and their constituents (fulvic acids, humic acids and humin and labile, non - labile and water - soluble carbon contents were evaluated two years and three months after the experiment implementation to determine the carbon lability (L lability index (LI, partitioning index (CPI and management index (CMI. The greatest carbon, nitrogen and organic matter contents in the soil surface layer (0.00 - 0.05 m were found in crops under no - till system (NTS, especially maize. The crops under NTS presented greater carbon content in humic substances than the conventional tillage system (CTS ones in the layer 0.05 - 0.10 m. The crops under NTS presented greater sustainability in the Brazilian semiarid region compared with those under CTS, as shown by their higher CMI in the soil surface layer.

Marginalization and School Nursing

Science.gov (United States)

Smith, Julia Ann

2004-01-01

The concept of marginalization was first analyzed by nursing researchers Hall, Stevens, and Meleis. Although nursing literature frequently refers to this concept when addressing "at risk" groups such as the homeless, gays and lesbians, and those infected with HIV/AIDS, the concept can also be applied to nursing. Analysis of current school nursing…

Margins for geometric uncertainty around organs at risk in radiotherapy

International Nuclear Information System (INIS)

McKenzie, Alan; Herk, Marcel van; Mijnheer, Ben

2002-01-01

Background and purpose: ICRU Report 62 suggests drawing margins around organs at risk (ORs) to produce planning organ at risk volumes (PRVs) to account for geometric uncertainty in the radiotherapy treatment process. This paper proposes an algorithm for drawing such margins, and compares the recommended margin widths with examples from clinical practice and discusses the limitations of the approach. Method: The use of the PRV defined in this way is that, despite the geometric uncertainties, the dose calculated within the PRV by the treatment planning system can be used to represent the dose in the OR with a certain confidence level. A suitable level is where, in the majority of cases (90%), the dose-volume histogram of the PRV will not under-represent the high-dose components in the OR. In order to provide guidelines on how to do this in clinical practice, this paper distinguishes types of OR in terms of the tolerance doses relative to the prescription dose and suggests appropriate margins for serial-structure and parallel-structure ORs. Results: In some instances of large and parallel ORs, the clinician may judge that the complication risk in omitting a margin is acceptable. Otherwise, for all types of OR, systematic, treatment preparation uncertainties may be accommodated by an OR→PRV margin width of 1.3Σ. Here, Σ is the standard deviation of the combined systematic (treatment preparation) uncertainties. In the case of serial ORs or small, parallel ORs, the effects of blurring caused by daily treatment execution errors (set-up and organ motion) should be taken into account. Near a region of high dose, blurring tends to shift the isodoses away from the unblurred edge as shown on the treatment planning system by an amount that may be represented by 0.5σ. This margin may be used either to increase or to decrease the margin already calculated for systematic uncertainties, depending upon the size of the tolerance dose relative to the detailed planned dose

PORTRAIT GRAFFITI IN MARGINS OF ANTIQUE LITHUANIAN BOOKS

Directory of Open Access Journals (Sweden)

Burba, Domininkas

2006-12-01

Full Text Available This article presents and discusses fourteen drawings that portray a human and were found in manuscripts and printed books (documents that were actively used in Lithuania from 17th to 19th centuries. All the drawings were made in the margins of the documents. For the authors the drawings were not planned work but more like quips, scribbles and doodles. Therefore the terms portrait graffiti and (as a synonym portrait marginalia are used to describe the discussed portraits. According to the formal classification of marginal drawings (suggested by J. Liskeviciene two of the examined marginal portraits (no. 10 and 14 are classed as seperate and finished works with their own composition; ten marginal portraits (no. 2, 4, 5, 6, 7, 8, 9, 11, 12 and 13 represent the readers (document users sketch like drawings. Two other portraits (no. 1 and 3 are just scribbles that have nothing to do with artictic perception and are very close to book graffiti. From the artistic approcah the most sophisticated of the marginal portraits are “the hunt scene” (no. 14 and the late (first half of the 19th century “portrait of the teacher” (no. 13. In the viewpoint of documentary and social communication the discussed marginal drawings did not have a direct addressee. They were made not for public but for personal use. Paleographical, structural and content analysis of the document showed that the author of the “bearded nobleman” portrait (no. 2 could have been the elder of Merkine Antanas Kazimieras Sapiega. The political realia of Grand Duchy of Lithuania (from now GDL are reflected by the heart shaped portrait of a youngster who we can guess is portrayed weeping over the countries misfortunes and internal disagreements duringthe period of foreight military interventions in the years from 1733 to 1736. It was forbiden for scribes to daub on court files and other official GDL documents therefore the discussed graffiti could be linked to psychological stress and

Application of matrix singular value properties for evaluating gain and phase margins of multiloop systems. [stability margins for wing flutter suppression and drone lateral attitude control

Science.gov (United States)

Mukhopadhyay, V.; Newsom, J. R.

1982-01-01

A stability margin evaluation method in terms of simultaneous gain and phase changes in all loops of a multiloop system is presented. A universal gain-phase margin evaluation diagram is constructed by generalizing an existing method using matrix singular value properties. Using this diagram and computing the minimum singular value of the system return difference matrix over the operating frequency range, regions of guaranteed stability margins can be obtained. Singular values are computed for a wing flutter suppression and a drone lateral attitude control problem. The numerical results indicate that this method predicts quite conservative stability margins. In the second example if the eigenvalue magnitude is used instead of the singular value, as a measure of nearness to singularity, more realistic stability margins are obtained. However, this relaxed measure generally cannot guarantee global stability.

Hälsofrämjande fysisk aktivitet hos personer under adjuvant cancerbehandling relaterad till fatigue, livskvalitet samt self-efficacy

OpenAIRE

Zetterlund, Johanna

2016-01-01

Bakgrund Cancerdrabbade lider ofta av cancerrelaterad fatigue (CRF) och försämrad livskvalitet under och efter behandling. Hälsofrämjande fysisk aktivitet (HFA) kan minska risken för dessa negativa konsekvenser. HFA påverkas bl.a. av träningsrelaterad self-efficacy, dvs tilltron till egen förmåga att vara fysisk aktiv. Syfte Att undersöka HFA hos personer under adjuvant cancerbehandling vid diagnos och efter sex månader samt att undersöka om de med en stabil HFA hade lägre CRF, högre livskval...

Small cell lymphocytic variant of marginal zone lymphoma: A distinct form of marginal zone lymphoma derived from naïve B cells as a cutaneous counterpart to the naïve marginal zone lymphoma of splenic origin.

Science.gov (United States)

Magro, Cynthia M; Olson, Luke C

2018-02-21

Primary cutaneous marginal zone lymphoma most commonly represents an indolent form of cutaneous B cell lymphoma. However, epidermotropic marginal zone lymphoma, blastic marginal zone lymphoma and B cell dominant variants without isotype switching can be associated with extracutaneous dissemination. The presumptive cell of origin is a post germinal center B cell with plasmacytic features. In the extracutaneous setting, however, a naïve B cell origin has been proposed for a subset of marginal zone lymphomas, notably splenic marginal zone lymphoma. The author encountered 11 cases of atypical lymphocytic infiltration of the skin primarily occurring in older individuals with an upper arm and head and neck localization; there was a reproducible pattern of diffuse and nodular infiltration by small monomorphic-appearing B cells. Phenotypically, the infiltrate was one predominated by B cells exhibiting CD23 and IgD positivity without immunoreactivity for CD38 and there were either no plasma cells or only a few without light chain restriction. In cases presenting with a solitary lesion complete excision and/or radiation led to successful disease remission in all cases without recurrence or metastatic disease. Of three cases with multiple initial lesions, evidence of extracutaneous disease was seen in two cases and recurrence occurred in one case. No patients have died of lymphoma. Longer term follows up and additional cases are needed to determine if this subset of marginal zone lymphoma is associated with a worse prognosis. Copyright © 2018. Published by Elsevier Inc.

Crop rotation and seasonal effects on fatty acid profiles of neutral and phospholipids extracted from no-till agricultural soils

DEFF Research Database (Denmark)

Ferrari, Alejandro E.; Ravnskov, Sabine; Larsen, John

2015-01-01

practices while NLFA 20:0 appears to be a good marker of HRsoils despite season or location. The PLFA-based taxonomic biomarkers for total bacteria, Gramnegativebacteria and arbuscular mycorrhiza showed a significant trend NE>HR>LR in the wintersampling. HR management was also characterized by high levels......Analysis of phospholipids (PLFA) and neutral lipids fatty acids (NLFA) was used to characterizeno-till productive agricultural soils associated with different crop rotation levels, replicated across a400 km transect in the Argentinean pampas, during two sampling seasons, summer and winter...

Seismic safety margins research program overview

International Nuclear Information System (INIS)

Tokarz, F.J.; Smith, P.D.

1978-01-01

A multiyear seismic research program has been initiated at the Lawrence Livermore Laboratory. This program, the Seismic Safety Margins Research Program (SSMRP) is funded by the U.S. Nuclear Regulatory Commission, Office of Nuclear Regulatory Research. The program is designed to develop a probabilistic systems methodology for determining the seismic safety margins of nuclear power plants. Phase I, extending some 22 months, began in July 1978 at a funding level of approximately $4.3 million. Here we present an overview of the SSMRP. Included are discussions on the program objective, the approach to meet the program goal and objectives, end products, the probabilistic systems methodology, and planned activities for Phase I

Marketing margins and agricultural technology in Mozambique

DEFF Research Database (Denmark)

Arndt, Channing; Jensen, Henning Tarp; Robinson, Sherman

2000-01-01

of improved agricultural technology and lower marketing margins yield welfare gains across the economy. In addition, a combined scenario reveals significant synergy effects, as gains exceed the sum of gains from the individual scenarios. Relative welfare improvements are higher for poor rural households......Improvements in agricultural productivity and reductions in marketing costs in Mozambique are analysed using a computable general equilibrium (CGE) model. The model incorporates detailed marketing margins and separates household demand for marketed and home-produced goods. Individual simulations...

New evidence on the asymmetry in gasoline price: volatility versus margin?

International Nuclear Information System (INIS)

Abosedra, S.; Radchenko, S.

2006-01-01

This paper examines recent evidence on the role that gasoline margins and volatility play in the asymmetric response of gasoline prices to changes in oil prices at different stages of distribution process. In a regression model with margins, we find that margins are statistically significant in explaining asymmetry between crude oil and spot gasoline prices, spot gasoline prices and wholesale gasoline prices, and wholesale gasoline prices and retail prices. In a regression model with input volatility, we find evidence that volatility is responsible for asymmetry between wholesale gasoline prices and retail gasoline prices. When both, gasoline margins and gasoline volatility are included in the regression, we find evidence supporting margins, the search theory, volatility, the oligopolistic coordination theory and an explanation of asymmetry. (author)

Interpreting Marginal Effects in the Multinomial Logit Model

DEFF Research Database (Denmark)

Wulff, Jesper

2014-01-01

with a substantial increase in the probability of entering a foreign market using a joint venture, while increases in the unpredictability in the host country environment are associated with a lower probability of wholly owned subsidiaries and a higher probability of exporting entries....... that have entered foreign markets. Through the application of a multinomial logit model, careful analysis of the marginal effects is performed through graphical representations, marginal effects at the mean, average marginal effects and elasticities. I show that increasing cultural distance is associated......This paper presents the challenges when researchers interpret results about relationships between variables from discrete choice models with multiple outcomes. The recommended approach is demonstrated by testing predictions from transaction cost theory on a sample of 246 Scandinavian firms...

The Effects of Marginal Deviations on Behavioral Development.

Science.gov (United States)

Caprara, Gian Vittorio; Dodge, Kenneth A; Pastorelli, Concetta; Zelli, Arnaldo

2006-01-01

This investigation was conceptually framed within the theory of marginal deviations (Caprara & Zimbardo, 1996) and sought evidence for the general hypothesis that some children who initially show marginal behavioral problems may, over time, develop more serious problems depending partly on other personal and behavioral characteristics. To this end, the findings of two studies conducted, respectively, with American elementary school children and Italian middle school students are reviewed. These two studies show that hyperactivity, cognitive difficulties, low special preference, and lack of prosocial behavior increase a child's risk for growth in aggressive behavior over several school years. More importantly, they also show that equivalent levels of these risk factors have a greater impact on the development of children who, early on, were marginally aggressive.

Calculating the marginal costs of a district-heating utility

International Nuclear Information System (INIS)

Sjoedin, Joergen; Henning, Dag

2004-01-01

District heating plays an important role in the Swedish heat-market. At the same time, the price of district heating varies considerably among different district-heating utilities. A case study is performed here in which a Swedish utility is analysed using three different methods for calculating the marginal costs of heat supply: a manual spreadsheet method, an optimising linear-programming model, and a least-cost dispatch simulation model. Calculated marginal-costs, obtained with the three methods, turn out to be similar. The calculated marginal-costs are also compared to the actual heat tariff in use by the utility. Using prices based on marginal costs should be able to bring about an efficient resource-allocation. It is found that the fixed rate the utility uses today should be replaced by a time-of-use rate, which would give a more accurate signal for customers to change their heat consumptions. (Author)

Containment safety margins

International Nuclear Information System (INIS)

Von Riesemann, W.A.

1980-01-01

Objective of the Containment Safety Margins program is the development and verification of methodologies which are capable of reliably predicting the ultimate load-carrying capability of light water reactor containment structures under accident and severe environments. The program was initiated in June 1980 at Sandia and this paper addresses the first phase of the program which is essentially a planning effort. Brief comments are made about the second phase, which will involve testing of containment models

Fission product margin in burnup credit analyses

International Nuclear Information System (INIS)

Finck, P.J.; Stenberg, C.G.

1998-01-01

The US Department of Energy (DOE) is currently working toward the licensing of a methodology for using actinide-only burnup credit for the transportation of spent nuclear fuel (SNF). Important margins are built into this methodology. By using comparisons with a representative experimental database to determine bias factors, the methodology ensures that actinide concentrations and worths are estimated conservatively; furthermore, the negative net reactivity of certain actinides and all fission products (FPs) is not taken into account, thus providing additional margin. A future step of DOE's effort might aim at establishing an actinide and FP burnup credit methodology. The objective of this work is to establish the uncertainty to be applied to the total FP worth in SNF. This will serve two ends. First, it will support the current actinide-only methodology by demonstrating the margin available from FPs. Second, it will identify the major contributions to the uncertainty and help set priorities for future work

On marginally resolved objects in optical interferometry

Science.gov (United States)

Lachaume, R.

2003-03-01

With the present and soon-to-be breakthrough of optical interferometry, countless objects shall be within reach of interferometers; yet, most of them are expected to remain only marginally resolved with hectometric baselines. In this paper, we tackle the problem of deriving the properties of a marginally resolved object from its optical visibilities. We show that they depend on the moments of flux distribution of the object: centre, mean angular size, asymmetry, and curtosis. We also point out that the visibility amplitude is a second-order phenomenon, whereas the phase is a combination of a first-order term, giving the location of the photocentre, and a third-order term, more difficult to detect than the visibility amplitude, giving an asymmetry coefficient of the object. We then demonstrate that optical visibilities are not a good model constraint while the object stays marginally resolved, unless observations are carried out at different wavelengths. Finally, we show an application of this formalism to circumstellar discs.

News from the Library: Advancing light - SPIE Digital Library accessible to CERN till 31 March 2012

CERN Multimedia

CERN Library

2012-01-01

SPIE (Society of Photo-Optical Instrumentation Engineers) is a not-for-profit international society which publishes one of the largest collections of applied optics and photonics research papers in the world: the SPIE Digital Library.   This resource includes more than 300,000 technical papers from SPIE journals, e-books and conference proceedings from 1990 to the present. The SPIE Digital Library covers many areas of interest for CERN users, such as astronomy, nanotechnology, sensors, lasers, electro-optics and imaging. The CERN Library has trial access to the complete resource till 31 March 2012, don't hesitate to give it a try! Access to the SPIE Digital Library here. We welcome any comment or question at library.desk@cern.ch.

Lithosphere structure and subsidence evolution of the conjugate S-African and Argentine margins

Science.gov (United States)

Dressel, Ingo; Scheck-Wenderoth, Magdalena; Cacace, Mauro; Götze, Hans-Jürgen; Franke, Dieter

2016-04-01

The bathymetric evolution of the South Atlantic passive continental margins is a matter of debate. Though it is commonly accepted that passive margins experience thermal subsidence as a result of lithospheric cooling as well as load induced subsidence in response to sediment deposition it is disputed if the South Atlantic passive margins were affected by additional processes affecting the subsidence history after continental breakup. We present a subsidence analysis along the SW African margin and offshore Argentina and restore paleobathymetries to assess the subsidence evolution of the margin. These results are discussed with respect to mechanisms behind margin evolution. Therefore, we use available information about the lithosphere-scale present-day structural configuration of these margins as a starting point for the subsidence analysis. A multi 1D backward modelling method is applied to separate individual subsidence components such as the thermal- as well as the load induced subsidence and to restore paleobathymetries for the conjugate margins. The comparison of the restored paleobathymetries shows that the conjugate margins evolve differently: Continuous subsidence is obtained offshore Argentina whereas the subsidence history of the SW African margin is interrupted by phases of uplift. This differing results for both margins correlate also with different structural configurations of the subcrustal mantle. In the light of these results we discuss possible implications for uplift mechanisms.

Molecular markers in the surgical margin of oral carcinomas

DEFF Research Database (Denmark)

Bilde, A.; Buchwald, C. von; Dabelsteen, E.

2009-01-01

epithelium in the surgical resection margin may explain the local recurrence rate. The purpose of this study is to investigate the presence of senescence markers, which may represent early malignant changes in the margin that in routine pathological evaluations are classified as histologically normal...

Genetically Modified Herbicide-Tolerant Crops, Weeds, and Herbicides: Overview and Impact

Science.gov (United States)

Bonny, Sylvie

2016-01-01

Genetically modified (GM) crops have been and continue to be a subject of controversy despite their rapid adoption by farmers where approved. For the last two decades, an important matter of debate has been their impact on pesticide use, particularly for herbicide-tolerant (HT) crops. Some claim that these crops bring about a decrease in herbicide use, while others claim the opposite. In fact, since 1996, most cultivated GMOs have been GMHT crops, which involve the use of an associated herbicide, generally glyphosate. In their very first years of adoption, HT crops often led to some decrease in herbicide use. However, the repetition of glyphosate-tolerant crops and of glyphosate only applications in the same fields without sufficient alternation and herbicide diversity has contributed to the appearance of glyphosate-resistant weeds. These weeds have resulted in a rise in the use of glyphosate and other herbicides. This article explores this situation and the impacts of herbicide-resistant weeds, using an interdisciplinary approach and drawing on recent data. The paper analyzes the spread of GMHT crops worldwide and their consequences on herbicide use in the USA in particular. It then addresses the global development of glyphosate-resistant weeds and their impact, particularly focusing on the USA. Finally, the last section explores how industry, farmers, and weed scientists are coping with the spread of resistant weeds. The concluding comments deal more widely with trends in GM crops.

Marginal Fit Comparison of CAD/CAM Crowns Milled from Two Different Materials.

Science.gov (United States)

Azarbal, Atousa; Azarbal, Mohsen; Engelmeier, Robert L; Kunkel, Thomas C

2017-11-16

To evaluate the marginal fit of CAD/CAM copings milled from hybrid ceramic (Vita Enamic) blocks and lithium disilicate (IPS e.max CAD) blocks, and to evaluate the effect of crystallization firing on the marginal fit of lithium disilicate copings. A standardized metal die with a 1-mm-wide shoulder finish line was imaged using the CEREC AC Bluecam. The coping was designed using CEREC 3 software. The design was used to fabricate 15 lithium disilicate and 15 hybrid ceramic copings. Design and milling were accomplished by one operator. The copings were seated on the metal die using a pressure clamp with a uniform pressure of 5.5 lbs. A Macroview Microscope (14×) was used for direct viewing of the marginal gap. Four areas were imaged on each coping (buccal, distal, lingual, mesial). Image analysis software was used to measure the marginal gaps in μm at 15 randomly selected points on each of the four surfaces. A total of 60 measurements were made per specimen. For lithium disilicate copings the measurements for marginal gap were made before and after crystallization firing. Data were analyzed using paired t-test and Kruskal-Wallis test. The overall mean difference in marginal gap between the hybrid ceramic and crystallized lithium disilicate copings was statistically significant (p marginal gaps were measured for crystallized lithium disilicate copings. The overall mean difference in marginal gap before and after firing (precrystallized and crystallized lithium disilicate copings) showed an average of 62 μm increase in marginal gap after firing. This difference was also significant (p marginal gap discrepancy when comparing hybrid ceramic and lithium disilicate CAD/CAM crowns. Also crystallization firing can result in a significant increase in the marginal gap of lithium disilicate CAD/CAM crowns. © 2017 by the American College of Prosthodontists.

Air-sea interactions in the marginal ice zone

Directory of Open Access Journals (Sweden)

Seth Zippel

2016-03-01

Full Text Available Abstract The importance of waves in the Arctic Ocean has increased with the significant retreat of the seasonal sea-ice extent. Here, we use wind, wave, turbulence, and ice measurements to evaluate the response of the ocean surface to a given wind stress within the marginal ice zone, with a focus on the local wind input to waves and subsequent ocean surface turbulence. Observations are from the Beaufort Sea in the summer and early fall of 2014, with fractional ice cover of up to 50%. Observations showed strong damping and scattering of short waves, which, in turn, decreased the wind energy input to waves. Near-surface turbulent dissipation rates were also greatly reduced in partial ice cover. The reductions in waves and turbulence were balanced, suggesting that a wind-wave equilibrium is maintained in the marginal ice zone, though at levels much less than in open water. These results suggest that air-sea interactions are suppressed in the marginal ice zone relative to open ocean conditions at a given wind forcing, and this suppression may act as a feedback mechanism in expanding a persistent marginal ice zone throughout the Arctic.

Dopamine reward prediction error responses reflect marginal utility.

Science.gov (United States)

Stauffer, William R; Lak, Armin; Schultz, Wolfram

2014-11-03

Optimal choices require an accurate neuronal representation of economic value. In economics, utility functions are mathematical representations of subjective value that can be constructed from choices under risk. Utility usually exhibits a nonlinear relationship to physical reward value that corresponds to risk attitudes and reflects the increasing or decreasing marginal utility obtained with each additional unit of reward. Accordingly, neuronal reward responses coding utility should robustly reflect this nonlinearity. In two monkeys, we measured utility as a function of physical reward value from meaningful choices under risk (that adhered to first- and second-order stochastic dominance). The resulting nonlinear utility functions predicted the certainty equivalents for new gambles, indicating that the functions' shapes were meaningful. The monkeys were risk seeking (convex utility function) for low reward and risk avoiding (concave utility function) with higher amounts. Critically, the dopamine prediction error responses at the time of reward itself reflected the nonlinear utility functions measured at the time of choices. In particular, the reward response magnitude depended on the first derivative of the utility function and thus reflected the marginal utility. Furthermore, dopamine responses recorded outside of the task reflected the marginal utility of unpredicted reward. Accordingly, these responses were sufficient to train reinforcement learning models to predict the behaviorally defined expected utility of gambles. These data suggest a neuronal manifestation of marginal utility in dopamine neurons and indicate a common neuronal basis for fundamental explanatory constructs in animal learning theory (prediction error) and economic decision theory (marginal utility). Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Biological impact of geometric uncertainties: what margin is needed for intra-hepatic tumors?

International Nuclear Information System (INIS)

Kuo, Hsiang-Chi; Liu, Wen-Shan; Wu, Andrew; Mah, Dennis; Chuang, Keh-Shih; Hong, Linda; Yaparpalvi, Ravi; Guha, Chandan; Kalnicki, Shalom

2010-01-01

To evaluate and compare the biological impact on different proposed margin recipes for the same geometric uncertainties for intra-hepatic tumors with different tumor cell types or clinical stages. Three different margin recipes based on tumor motion were applied to sixteen IMRT plans with a total of twenty two intra-hepatic tumors. One recipe used the full amplitude of motion measured from patients to generate margins. A second used 70% of the full amplitude of motion, while the third had no margin for motion. The biological effects of geometric uncertainty in these three situations were evaluated with Equivalent Uniform Doses (EUD) for various survival fractions at 2 Gy (SF 2 ). There was no significant difference in the biological impact between the full motion margin and the 70% motion margin. Also, there was no significant difference between different tumor cell types. When the margin for motion was eliminated, the difference of the biological impact was significant among different cell types due to geometric uncertainties. Elimination of the motion margin requires dose escalation to compensate for the biological dose reduction due to the geometric misses during treatment. Both patient-based margins of full motion and of 70% motion are sufficient to prevent serious dosimetric error. Clinical implementation of margin reduction should consider the tumor sensitivity to radiation

Regrounding in Place: Paths to Native American Truths at the Margins

Science.gov (United States)

Lucas, Michael

2013-01-01

Margin acts as ground to receive the figure of the text. Margin is initially unreadable, but as suggested by gestalt studies, may be reversed, or regrounded. A humanities course, "Native American Architecture and Place," was created for a polytechnic student population, looking to place as an inroad for access to the margins of a better…

Safety margins in older adults increase with improved control of a dynamic object

Science.gov (United States)

Hasson, Christopher J.; Sternad, Dagmar

2014-01-01

Older adults face decreasing motor capabilities due to pervasive neuromuscular degradations. As a consequence, errors in movement control increase. Thus, older individuals should maintain larger safety margins than younger adults. While this has been shown for object manipulation tasks, several reports on whole-body activities, such as posture and locomotion, demonstrate age-related reductions in safety margins. This is despite increased costs for control errors, such as a fall. We posit that this paradox could be explained by the dynamic challenge presented by the body or also an external object, and that age-related reductions in safety margins are in part due to a decreased ability to control dynamics. To test this conjecture we used a virtual ball-in-cup task that had challenging dynamics, yet afforded an explicit rendering of the physics and safety margin. The hypotheses were: (1) When manipulating an object with challenging dynamics, older adults have smaller safety margins than younger adults. (2) Older adults increase their safety margins with practice. Nine young and 10 healthy older adults practiced moving the virtual ball-in-cup to a target location in exactly 2 s. The accuracy and precision of the timing error quantified skill, and the ball energy relative to an escape threshold quantified the safety margin. Compared to the young adults, older adults had increased timing errors, greater variability, and decreased safety margins. With practice, both young and older adults improved their ability to control the object with decreased timing errors and variability, and increased their safety margins. These results suggest that safety margins are related to the ability to control dynamics, and may explain why in tasks with simple dynamics older adults use adequate safety margins, but in more complex tasks, safety margins may be inadequate. Further, the results indicate that task-specific training may improve safety margins in older adults. PMID:25071566

Safety Margins in Older Adults Increase with Improved Control of a Dynamic Object

Directory of Open Access Journals (Sweden)

Christopher James Hasson

2014-07-01

Full Text Available Older adults face decreasing motor capabilities due to pervasive neuromuscular degradations. As a consequence errors in movement control increase. Thus, older individuals should maintain larger safety margins than younger adults. While this has been shown for object manipulation tasks, several reports on whole-body activities, such as posture and locomotion, however demonstrate age-related reductions in safety margins. This is despite increased costs for control errors, such as a fall. We posit that this paradox could be explained by the dynamic challenge presented by the body or an external object, and that age-related reductions in safety margins are in part due to a decreased ability to control dynamics. To test this conjecture we used a virtual ball-in-cup task that had challenging dynamics, yet afforded an explicit rendering of the physics and safety margin. The hypotheses were: 1 When manipulating an object with challenging dynamics, older adults have smaller safety margins than younger adults. 2 Older adults increase their safety margins with practice. Nine young and 10 healthy older adults practiced moving the virtual ball-in-cup to a target location in exactly two seconds. The accuracy and precision of the timing error quantified skill and the ball energy relative to an escape threshold quantified the safety margin. Compared to the young adults, older adults had increased timing errors, greater variability, and decreased safety margins. With practice, both young and older adults improved their ability to control the object with decreased timing errors and variability, and increased their safety margins. These results suggest that safety margins are related to the ability to control dynamics, and may explain why in tasks with simple dynamics older adults use adequate safety margins, but in more complex tasks, safety margins may be inadequate. Further, the results indicate that task-specific training may improve safety margins in older

Texas curve margin of safety.

Science.gov (United States)

2013-01-01

This software can be used to assist with the assessment of margin of safety for a horizontal curve. It is intended for use by engineers and technicians responsible for safety analysis or management of rural highway pavement or traffic control devices...

Marginality and Social Rejection in Amiri Baraka's Slave Ship

Directory of Open Access Journals (Sweden)

Hamid Hammad Abed

2016-11-01

Full Text Available Marginality and social rejection are the most influential matters exploited by Baraka to intentionally criticize the American society.  More often than not, these two matters have become the scenes of major or minor acts of humiliation and dehumanization that threaten to violate the ethical rules of living. This paper aims at investigating the impact of marginality and social rejection on a number of black characters in Baraka's Slave Ship who are brought to America to be sold as commodities. It is divided into two sections and conclusion. Section one deals with Amiri Baraka’s dramatic thought and experience of marginality within the American society. The textual analysis of Slave Ship is investigated in section two. The significance of the study lies in its textual exploration of the impact of marginality and social rejection in subverting the American dream of democracy, freedom, and equality in Baraka’s Slave Ship.

Marginal Bone Loss after Ten Years in an Adult Danish Population: A Radiographic Study.

Science.gov (United States)

Bahrami, Golnosh; Vaeth, Michael; Wenzel, Ann; Isidor, Flemming

To evaluate marginal bone loss over a 10-year period in individuals and in tooth groups in relation to age and level of marginal bone. In 1997, 616 randomly selected individuals (mean age: 42 years, range: 21-63 years) underwent a full-mouth radiographic survey. In 2008, the survey was repeated in 362 of the same individuals (182 women and 180 men). The marginal bone level of each tooth was measured in mm from the cementoenamel junction to the marginal bone. These measurements were used to calculate marginal bone loss during the 10-year period for individuals and tooth groups in relation to age and to baseline marginal bone level, calculated as the average between measurements in 1997 and 2008 to circumvent regression towards the mean. The average annual marginal bone loss was 0.09 mm (SD ± 0.04 mm) during the 10-year study period. The association between marginal bone loss and baseline marginal bone level was more pronounced in the youngest age group, compared to the other age groups. Molars displayed the most severe bone loss during the study period. Marginal bone loss over a 10-year period is associated with age and baseline marginal bone level. Younger individuals with a reduced marginal bone level were at higher risk for further bone loss. Molars lose marginal bone more rapidly than other tooth groups.

An ongoing hydro-biogeochemical characterization of a partly drained lowland in a clay till subcatchment

DEFF Research Database (Denmark)

Prinds, Christian; Petersen, Rasmus Jes; Iversen, Bo Vangsø

2016-01-01

as well as novel approaches e.g. remote sensing using UAV’s (Unmanned Aerial Vehicles commonly known as drones), a newly developed redox probe, and novel uses of geophysical methods. More information about TReNDS can be found at www.nitrat.dk. The project is funded by Innovation Fund Denmark......Riparian lowlands may have significant impact on the catchment nitrate balance. As a part of the strategic research project TReNDS (“Transport and reduction of nitrate in Danish landscapes at various scales”) extensive field investigations have commenced in the Fensholt subcatchment situated within...... Norsminde Fjord catchment, Odder, Denmark. The riparian lowlands are surrounded by a hilly landscape composed of mainly clayey till, and hence the landscape is heavily drained. Drainpipes are either disconnected at the hillslope bordering the riparian lowland or discharging partly through the riparian zone...

Participatory democracy and Hillary Clinton’s marginalized fandom

Directory of Open Access Journals (Sweden)

Abigail De Kosnik

2008-09-01

Full Text Available After the drawn-out, heated contest for the Democratic Party presidential nomination and Senator Obama's victory over Senator Clinton, a segment of Clinton's supporters are threatening to leave the party rather than fall in line behind the nominee. This essay argues that the battle between Clinton's and Obama's followers is best understood as a war between fan bases, with Obama enthusiasts constituting as the dominant fandom and Clinton voters occupying the position of marginalized fandom. Marginalized fandoms tend to blame the opposing fan base, intermediaries, and The Powers That Be for their fan campaigns' losses, and Clinton's fans are adhering to this pattern. However, the Clinton marginalized fandom's complaints can be regarded as valuable critiques that, if noted rather than dismissed, could greatly strengthen participatory democracy in the United States.

Planning target volumes for radiotherapy: how much margin is needed?

International Nuclear Information System (INIS)

Antolak, John A.; Rosen, Isaac I.

1999-01-01

Purpose: The radiotherapy planning target volume (PTV) encloses the clinical target volume (CTV) with anisotropic margins to account for possible uncertainties in beam alignment, patient positioning, organ motion, and organ deformation. Ideally, the CTV-PTV margin should be determined solely by the magnitudes of the uncertainties involved. In practice, the clinician usually also considers doses to abutting healthy tissues when deciding on the size of the CTV-PTV margin. This study calculates the ideal size of the CTV-PTV margin when only physical position uncertainties are considered. Methods and Materials: The position of the CTV for any treatment is assumed to be described by independent Gaussian distributions in each of the three Cartesian directions. Three strategies for choosing a CTV-PTV margin are analyzed. The CTV-PTV margin can be based on: 1. the probability that the CTV is completely enclosed by the PTV; 2. the probability that the projection of the CTV in the beam's eye view (BEV) is completely enclosed by the projection of the PTV in the BEV; and 3. the probability that a point on the edge of the CTV is within the PTV. Cumulative probability distributions are derived for each of the above strategies. Results: Expansion of the CTV by 1 standard deviation (SD) in each direction results in the CTV being entirely enclosed within the PTV 24% of the time; the BEV projection of the CTV is enclosed within the BEV projection of the PTV 39% of the time; and a point on the edge of the CTV is within the PTV 84% of the time. To have the CTV enclosed entirely within the PTV 95% of the time requires a margin of 2.8 SD. For the BEV projection of the CTV to be within the BEV projection of the PTV 95% of the time requires a margin of 2.45 SD. To have any point on the surface of the CTV be within the PTV 95% of the time requires a margin of 1.65 SD. Conclusion: In the first two strategies for selecting a margin, the probability of finding the CTV within the PTV is

Marginal Loss Calculations for the DCOPF

Energy Technology Data Exchange (ETDEWEB)

Eldridge, Brent [Federal Energy Regulatory Commission, Washington, DC (United States); Johns Hopkins Univ., Baltimore, MD (United States); O' Neill, Richard P. [Federal Energy Regulatory Commission, Washington, DC (United States); Castillo, Andrea R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2016-12-05

The purpose of this paper is to explain some aspects of including a marginal line loss approximation in the DCOPF. The DCOPF optimizes electric generator dispatch using simplified power flow physics. Since the standard assumptions in the DCOPF include a lossless network, a number of modifications have to be added to the model. Calculating marginal losses allows the DCOPF to optimize the location of power generation, so that generators that are closer to demand centers are relatively cheaper than remote generation. The problem formulations discussed in this paper will simplify many aspects of practical electric dispatch implementations in use today, but will include sufficient detail to demonstrate a few points with regard to the handling of losses.

Marginalism, quasi-marginalism and critical phenomena in micellar solutions

International Nuclear Information System (INIS)

Reatto, L.

1986-01-01

The observed nonuniversal critical behaviour of some micellar solutions is interpreted in terms of quasi-marginalism, i.e. the presence of a coupling which scales with an exponent very close to the spatial dimensionality. This can give rise to a preasymptotic region with varying effective critical exponents with a final crossover to the Ising ones. The reduced crossover temperature is estimated to be below 10 -6 . The exponents β and γ measured in C 12 e 5 are in good agreement with the scaling law expected to hold for the effective exponents. The model considered by Shnidman is found unable to explain the nonuniversal critical behaviour

Passive margins getting squeezed in the mantle convection vice

Science.gov (United States)

Yamato, Philippe; Husson, Laurent; Becker, Thorsten W.; Pedoja, Kevin

2014-05-01

Passive margins often exhibit uplift, exhumation and tectonic inversion. We speculate that the compression in the lithosphere gradually increased during the Cenozoic. In the same time, the many mountain belts at active margins that accompany this event seem readily witness this increase. However, how that compression increase affects passive margins remains unclear. In order to address this issue, we design a 2D viscous numerical model wherein a lithospheric plate rests above a weaker mantle. It is driven by a mantle conveyor belt, alternatively excited by a lateral downwelling on one side, an upwelling on the other side, or both simultaneously. The lateral edges of the plate are either free or fixed, representing the cases of free convergence, and collision or slab anchoring, respectively. This distinction changes the upper boundary condition for mantle circulation and, as a consequence, the stress field. Our results show that between these two regimes, the flow pattern transiently evolves from a free-slip convection mode towards a no-slip boundary condition above the upper mantle. In the second case, the lithosphere is highly stressed horizontally and deforms. For an equivalent bulk driving force, compression increases drastically at passive margins provided that upwellings are active. Conversely, if downwellings alone are activated, compression occurs at short distances from the trench and extension prevails elsewhere. These results are supported by Earth-like 3D spherical models that reveal the same pattern, where active upwellings are required to excite passive margins compression. These results support the idea that compression at passive margins, is the response to the underlying mantle flow, that is increasingly resisted by the Cenozoic collisions.

Pricing district heating by marginal cost

International Nuclear Information System (INIS)

Difs, Kristina; Trygg, Louise

2009-01-01

A vital measure for industries when redirecting the energy systems towards sustainability is conversion from electricity to district heating (DH). This conversion can be achieved for example, by replacing electrical heating with DH and compression cooling with heat-driven absorption cooling. Conversion to DH must, however, always be an economically attractive choice for an industry. In this paper the effects for industries and the local DH supplier are analysed when pricing DH by marginal cost in combination with industrial energy efficiency measures. Energy audits have shown that the analysed industries can reduce their annual electricity use by 30% and increase the use of DH by 56%. When marginal costs are applied as DH tariffs and the industrial energy efficiency measures are implemented, the industrial energy costs can be reduced by 17%. When implementing the industrial energy efficiency measures and also considering a utility investment in the local energy system, the local DH supplier has a potential to reduce the total energy system cost by 1.6 million EUR. Global carbon dioxide emissions can be reduced by 25,000 tonnes if the industrial energy efficiency measures are implemented and when coal-condensing power is assumed to be the marginal electricity source

Marginalized Student Access to Technology Education

Science.gov (United States)

Kurtcu, Wanda M.

The purpose of this paper is to investigate how a teacher can disrupt an established curriculum that continues the cycle of inequity of access to science, technology, engineering, and math (STEM) curriculum by students in alternative education. For this paper, I will focus on the technology components of the STEM curriculum. Technology in the United States, if not the world economy, is developing at a rapid pace. Many areas of day to day living, from applying for a job to checking one's bank account online, involve a component of science and technology. The 'gap' in technology education is emphasized between the 'haves and have-nots', which is delineated along socio-economic lines. Marginalized students in alternative education programs use this equipment for little else than remedial programs and credit recovery. This level of inequity further widens in alternative education programs and affects the achievement of marginalized students in credit recovery or alternative education classes instead of participation technology classes. For the purposes of this paper I focus on how can I decrease the inequity of student access to 21st century technology education in an alternative education program by addressing the established curriculum of the program and modifying structural barriers of marginalized student access to a technology focused curriculum.

Geomorphic response of a continental margin to tectonic and eustatic variations, the Levant margin during the Messinian Salinity Crisis

Science.gov (United States)

Ben Moshe, Liran; Ben-Avraham, Zvi; Enzel, Yehouda; Uri, Schattner

2017-04-01

During the Messinian Salinity Crisis (MSC, 5.97±0.01-5.33 Ma) the Mediterranean Levant margin experienced major eustatic and sedimentary cycles as well as tectonic motion along the nearby Dead Sea fault plate boundary. New structures formed along this margin with morphology responding to these changes. Our study focuses on changes in this morphology across the margin. It is based on interpretation of three 3D seismic reflection volumes from offshore Israel. Multi-attribute analysis aided the extraction of key reflectors. Morphologic analysis of these data quantified interacting eustasy, sedimentation, and tectonics. Late Messinian morphologic domains include: (a) continental shelf; (b) 'Delta' anticline, forming a ridge diagonal to the strike of the margin; (c) southward dipping 'Hadera' valley, separating between (a) and (b); (d) 'Delta Gap' - a water gap crossing perpendicular to the anticline axis, exhibiting a sinuous thalweg; (e) continental slope. Drainage across the margin developed in several stages. Remains of turbidite flows crossing the margin down-slope were spotted across the 'Delta' anticline. These flows accumulated with the MSC evaporate sequence and prior to the anticline folding. Rising of the anticline, above the then bathymetry, either blocked or diverted the turbidites. That rising also defined the Hadera valley. In-situ evaporates, covering the valley floor, are, in turn covered by a fan-delta at the distal end of the valley. The fan-delta complex contains eroded evaporites and Lago-Mare fauna. Its top is truncated by dendritic fluvial channels that drained towards the Delta Gap. The Delta Gap was carved through the Delta ridge in a morphological and structural transition zone. We propose that during the first stages of the MSC (5.97±0.01-5.59 ma) destabilization of the continental slope due to oscillating sea level produced gravity currents that flowed through the pre-existing Delta anticline. Subsequent folding of the Delta anticline

Deep continental margin reflectors

Science.gov (United States)

Ewing, J.; Heirtzler, J.; Purdy, M.; Klitgord, Kim D.

1985-01-01

In contrast to the rarity of such observations a decade ago, seismic reflecting and refracting horizons are now being observed to Moho depths under continental shelves in a number of places. These observations provide knowledge of the entire crustal thickness from the shoreline to the oceanic crust on passive margins and supplement Consortium for Continental Reflection Profiling (COCORP)-type measurements on land.

Perforated marginal ulcers after laparoscopic gastric bypass.

Science.gov (United States)

Felix, Edward L; Kettelle, John; Mobley, Elijah; Swartz, Daniel

2008-10-01

Perforated marginal ulcer (PMU) after laparoscopic Roux-en-Y gastric bypass (LRYGB) is a serious complication, but its incidence and etiology have rarely been investigated. Therefore, a retrospective review of all patients undergoing LRYGB at the authors' center was conducted to determine the incidence of PMU and whether any causative factors were present. A prospectively kept database of all patients at the authors' bariatric center was retrospectively reviewed. The complete records of patients with a PMU were examined individually for accuracy and analyzed for treatment, outcome, and possible underlying causes of the marginal perforation. Between April 1999 and August 2007, 1% of the patients (35/3,430) undergoing laparoscopic gastric bypass experienced one or more perforated marginal ulcers 3 to 70 months (median, 18 months) after LRYGB. The patients with and without perforation were not significantly different in terms of mean age (37 vs 41 years), weight (286 vs 287 lb), body mass index (BMI) (46 vs 47), or female gender (89% vs 83%). Of the patients with perforations, 2 (6%) were taking steroids, 10 (29%) were receiving nonsteroidal antiinflammatory drugs (NSAIDs) at the time of the perforation, 18 (51%) were actively smoking, and 6 of the smokers also were taking NSAIDs. Eleven of the patients (31%) who perforated did not have at least one of these possible risk factors, but 4 (36%) of the 11 patients in this group had been treated after bypass for a marginal ulcer. Only 7 (20%) of the 35 patients who had laparoscopic bypass, or 7 (0.2%) in the entire group of 3,430 patients, perforated without any warning. There were no deaths, but three patients reperforated. The incidence of a marginal ulcer perforating after LRYGB was significant (>1%) and appeared to be related to smoking or the use of NSAIDs or steroids. Because only 0.2% of all patients acutely perforated without some risk factor or warning, long-term ulcer prophylaxis or treatment may be necessary

Tiago Marques Aipobureu: um bororo marginal Tiago Marques Aipobureu: a Bororo on the margins

Directory of Open Access Journals (Sweden)

Florestan Fernandes

2007-11-01

Full Text Available O texto analisa a biografia de um membro da tribo dos Bororo, Tiago Marques Aipobureu, que, nascido no planalto oriental de Mato Grosso, foi levado pelos missionários para estudar em Cuiabá e depois viajou pela Europa. Quando de seu retorno ao Brasil, foi empregado como professor, mas não conseguiu adaptar-se à nova vida. Casado com uma mulher de sua tribo, buscou então reintegrar-se aos Bororo, igualmente sem sucesso. Permanecia, desse modo, no meio do caminho, incapaz de integrar-se plenamente tanto à sociedade e cultura "civilizadas" como à sociedade e cultura indígenas. O desajustamento de Tiago evidencia a situação do homem marginal, daquele que se situa na divisa de duas raças, na margem de duas culturas sem conseguir pertencer integralmente a nenhuma delas.The text analyzes the biography of a member of the Bororo tribe, Tiago Marques Aipobureu. Born on the eastern plateau of Mato Grosso, he was taken by missionaries to study in Cuiabá and later travelled through Europe. On returning to Brazil, he was employed as a teacher, but was unable to adapt to his new life. Married to a woman from his tribe, he tried to rejoin the Bororo, likewise without success. Thus he found himself midway between worlds, unable to join fully either 'civilized' society and culture, or indigenous society and culture. Tiago's maladjustment exemplifies the situation of the marginal person, someone situated on the dividing line between two races, on the margin of two cultures, unable to belong wholly to either.

Permian-Triassic Tethyan realm reorganization: Implications for the outward Pangea margin

Science.gov (United States)

Riel, Nicolas; Jaillard, Etienne; Martelat, Jean-Emmanuel; Guillot, Stéphane; Braun, Jean

2018-01-01

We present a new conceptual model to explain the first order Permian-Triassic evolution of the whole > 30 000 km long Pangea margin facing the Panthalassa ocean. Compilation of available geological, geochemical, geochronogical and paleomagnetic data all along this system allowed us to distinguish three part of the margin: western Laurentia, western Gondwana and eastern Gondwana. These segments record distinct tectonic and magmatic events, which all occur synchronously along the whole margin and correlate well with the main geodynamic events of this period, i.e. subduction of the Paleotethys mid-ocean ridge at 310-280 Ma, opening of the Neotethys at 280-260 Ma, counterclockwise rotation of Pangea at 260-230 Ma and closure of the Paleotethys at 230-220 Ma. Between 260 and 230 Ma, the reorganization of the Tethyan realm triggered the up to 35° rotation of Pangea around an Euler pole located in northernmost South America. This implied both an increase and a decrease of the convergence rate between the margin and the Panthalassa ocean, north and south of the Euler pole, respectively. Thus, the Permian-Triassic Pangean margin was marked: in western Laurentia by marginal sea closure, in western Gondwana by widespread bimodal magmatic and volcanic activity, in eastern Gondwana by transpressive orogenic phase. Therefore, we propose that the Permian-Triassic evolution of the outward margin of Pangea was controlled by the Tethyan realm reorganization.

Marginal pricing of transmission services. An analysis of cost recovery

Energy Technology Data Exchange (ETDEWEB)

Perez-Arriaga, I.J.., Rubio, F.J. [Instituto de Investigacion Technologica, Universidad Pontificia Comillas, Madrid (Spain); Puerta, J.F.; Arceluz, J.; Marin, J. [Unidad de Planificacion Estrategica, Iberdrola, Madrid (Spain)

1996-12-31

The authors present an in-depth analysis of network revenues that are computed with marginal pricing, and investigate the reasons why marginal prices in actual power systems fail to recover total incurred network costs. The major causes of the failure are identified and illustrated with numerical examples. The paper analyzes the regulatory implications of marginal network pricing in the context of competitive electricity markets and provides suggestions for the meaningful allocation of network costs among users. 5 figs., 9 tabs., 8 refs.

Marginal pricing of transmission services. An analysis of cost recovery

International Nuclear Information System (INIS)

Perez-Arriaga, I.J.., Rubio, F.J.; Puerta, J.F.; Arceluz, J.; Marin, J.

1996-01-01

The authors present an in-depth analysis of network revenues that are computed with marginal pricing, and investigate the reasons why marginal prices in actual power systems fail to recover total incurred network costs. The major causes of the failure are identified and illustrated with numerical examples. The paper analyzes the regulatory implications of marginal network pricing in the context of competitive electricity markets and provides suggestions for the meaningful allocation of network costs among users. 5 figs., 9 tabs., 8 refs

The origin of Karaj dam basement sill marginal reversal by Soret fractionation

Science.gov (United States)

Maghdour-Mashhour, Reza; Esmaeily, Dariush

2010-05-01

The Karaj dam basement sill (KDBS), located North West of Tehran, northern Iran, is one of the several E-W-trending plutons in the Albourz Mountains. The KDBS consists of a layered series between upper and lower chilled margins. The rocks of the chilled margins are gabbroic in composition and porphyritic, with euhedral to subhedral plagioclase and clinopyroxene megacrysts up to 5 mm long. The rocks become coarse-grained toward the center of the sill and show a gradual transition from porphyritic to equigranular texture. Field and petrographic observations reveal a reverse trend in marginal units crystallization from the eutectic point to the main magma composition; i.e., the olivine-bearing gabbro (porphyritic chilled margin), which has a eutectic composition, crystallized prior to the marginal gabbros, which have a cotectic or near-cotectic composition, as plagioclase laths in the gabbroic unit are embedded in large crystals of clinopyroxene and this phenomenon is believed to result from the cotectic crystallization of plagioclase and clinopyroxene. Four major mechanisms are proposed and discussed in order to find the exact mechanism responsible for marginal reversal formation as following: 1) Crystal settling is a gravity-dependent mechanism and phenocrysts must have settled to form a layer at the bottom of the sill, showing sharp upper boundary which is not observable in KDBS. Besides, the reverse fractionation of inwardly-dipping sequence of mentioned sill occurs in layers with primary dips up to 55°. Consequently capability of marginal reversals to develop along steeply inclined chamber margins, by this mechanism is implausible. 2) Multiple injections of successive magma pulses fails to explain the origin of marginal reversal since the transition along the entire length of marginal reversal is gradual also there is no compositional break or chilled contact between two mentioned units of KDBS margin (Olivine-gabbro and marginal gabbro). 3) The idea of

Experimental validation of the van Herk margin formula for lung radiation therapy

International Nuclear Information System (INIS)

Ecclestone, Gillian; Heath, Emily; Bissonnette, Jean-Pierre

2013-01-01

Purpose: To validate the van Herk margin formula for lung radiation therapy using realistic dose calculation algorithms and respiratory motion modeling. The robustness of the margin formula against variations in lesion size, peak-to-peak motion amplitude, tissue density, treatment technique, and plan conformity was assessed, along with the margin formula assumption of a homogeneous dose distribution with perfect plan conformity.Methods: 3DCRT and IMRT lung treatment plans were generated within the ORBIT treatment planning platform (RaySearch Laboratories, Sweden) on 4DCT datasets of virtual phantoms. Random and systematic respiratory motion induced errors were simulated using deformable registration and dose accumulation tools available within ORBIT for simulated cases of varying lesion sizes, peak-to-peak motion amplitudes, tissue densities, and plan conformities. A detailed comparison between the margin formula dose profile model, the planned dose profiles, and penumbra widths was also conducted to test the assumptions of the margin formula. Finally, a correction to account for imperfect plan conformity was tested as well as a novel application of the margin formula that accounts for the patient-specific motion trajectory.Results: The van Herk margin formula ensured full clinical target volume coverage for all 3DCRT and IMRT plans of all conformities with the exception of small lesions in soft tissue. No dosimetric trends with respect to plan technique or lesion size were observed for the systematic and random error simulations. However, accumulated plans showed that plan conformity decreased with increasing tumor motion amplitude. When comparing dose profiles assumed in the margin formula model to the treatment plans, discrepancies in the low dose regions were observed for the random and systematic error simulations. However, the margin formula respected, in all experiments, the 95% dose coverage required for planning target volume (PTV) margin derivation, as

Energy system analysis of marginal electricity supply in consequential LCA

DEFF Research Database (Denmark)

Lund, Henrik; Mathiesen, Brian Vad; Christensen, Per

2010-01-01

Background, aim and scope This paper discusses the identification of the environmental consequences of marginal electricity supplies in consequential life cycle assessments (LCA). According to the methodology, environmental characteristics can be examined by identifying affected activities, i...... in capacity but can be characterised as a complex set of affected electricity and heat supply technologies. A long-term YAM technology is identified for the Danish BAU2030 system in the case of three different long-term marginal changes in capacity, namely coal, natural gas or wind power. Discussion Four...... of four different situations are provided. We suggest that the technology mix with the installation of natural gas or coal power plant is applied as the marginal capacity. Conclusions The environmental consequences of marginal changes in electricity supply cannot always be represented solely by long...

Can pro-marriage policies work? An analysis of marginal marriages.

Science.gov (United States)

Frimmel, Wolfgang; Halla, Martin; Winter-Ebmer, Rudolf

2014-08-01

Policies to promote marriage are controversial, and it is unclear whether they are successful. To analyze such policies, one must distinguish between a marriage that is created by a marriage-promoting policy (marginal marriage) and a marriage that would have been formed even in the absence of a state intervention (average marriage). We exploit the suspension of a cash-on-hand marriage subsidy in Austria to examine the differential behavior of marginal and average marriages. The announcement of an impending suspension of this subsidy led to an enormous marriage boom among eligible couples that allows us to locate marginal marriages. Applying a difference-in-differences approach, we show that marginal marriages are surprisingly as stable as average marriages but produce fewer children, children later in marriage, and children who are less healthy at birth.

Marginal Teachers from the Eyes of School Principals: Concept, Problems and Management Strategies

Science.gov (United States)

Erdogan, Cetin; Demirkasimoglu, Nihan

2016-01-01

This research aimed to determine how Turkish principals define marginal teachers and which strategies they use to deal with them. Within this purpose, the following points are examined: (a) the concept of marginal teacher, (b) the underlying reasons for marginal teacher behaviors, (c) the problems marginal teachers cause in school settings, (d)…

Seismic margin review of the Maine Yankee Atomic Power Station: Fragility analysis

International Nuclear Information System (INIS)

Ravindra, M.K.; Hardy, G.S.; Hashimoto, P.S.; Griffin, M.J.

1987-03-01

This Fragility Analysis is the third of three volumes for the Seismic Margin Review of the Maine Yankee Atomic Power Station. Volume 1 is the Summary Report of the first trial seismic margin review. Volume 2, Systems Analysis, documents the results of the systems screening for the review. The three volumes are part of the Seismic Margins Program initiated in 1984 by the Nuclear Regulatory Commission (NRC) to quantify seismic margins at nuclear power plants. The overall objectives of the trial review are to assess the seismic margins of a particular pressurized water reactor, and to test the adequacy of this review approach, quantification techniques, and guidelines for performing the review. Results from the trial review will be used to revise the seismic margin methodology and guidelines so that the NRC and industry can readily apply them to assess the inherent quantitative seismic capacity of nuclear power plants

Seismic margin review of the Maine Yankee Atomic Power Station: Fragility analysis

Energy Technology Data Exchange (ETDEWEB)

Ravindra, M. K.; Hardy, G. S.; Hashimoto, P. S.; Griffin, M. J.

1987-03-01

This Fragility Analysis is the third of three volumes for the Seismic Margin Review of the Maine Yankee Atomic Power Station. Volume 1 is the Summary Report of the first trial seismic margin review. Volume 2, Systems Analysis, documents the results of the systems screening for the review. The three volumes are part of the Seismic Margins Program initiated in 1984 by the Nuclear Regulatory Commission (NRC) to quantify seismic margins at nuclear power plants. The overall objectives of the trial review are to assess the seismic margins of a particular pressurized water reactor, and to test the adequacy of this review approach, quantification techniques, and guidelines for performing the review. Results from the trial review will be used to revise the seismic margin methodology and guidelines so that the NRC and industry can readily apply them to assess the inherent quantitative seismic capacity of nuclear power plants.

Margin of Valuation Error Among Nigerian Valuers: Postulating an ...

African Journals Online (AJOL)

Study on margin of error aims at capturing the response of Nigerian valuers and their clients from the financial sector to their permissable margin of error with a view to establishing the bracket outside which the valuer is considered incompetent. The opinion of 300 Estate Surveyors and Valuers were sampled using simple ...

Ethnographies of marginality [Review article

NARCIS (Netherlands)

Beuving, J.J.

2016-01-01

Africanist discourse today displays a strong, widespread and growing sense of optimism about Africa's economic future. After decades of decline and stagnation in which Africa found itself reduced to the margins of the global economic stage, upbeat Afro-optimism seems fully justified. One only needs

Influence of abutment screw preload on stress distribution in marginal bone.

Science.gov (United States)

Khraisat, Ameen

2012-01-01

Changes in an implant assembly after abutment connection might possibly cause deformation in the implant/abutment joint and even in the marginal bone. The aim of this study was to evaluate the influence of abutment screw preload through the implant collar on marginal bone stress without external load application. Models of three implant parts made of titanium (implant, abutment, and abutment screw) and cortical bone were built and positioned with computer-aided design software. Meshing and generation of boundary conditions, loads, and interactions were performed. Each part was meshed independently. The sole load applied to the model was a torque of 32 Ncm on the abutment screw about its axis of rotation. The implant collar was deformed axially after the screw was tightened (3 μm). This deformation resulted in 60 MPa of stress in the marginal bone. Moreover, pressure on the marginal bone in a radial direction was observed. It can be concluded that, without any external load application, abutment screw preload exerts stresses on the implant collar and the marginal bone. These findings should help guide the development of new implant/abutment joint designs that exert less stress on the marginal bone.

A Longitudinal View of the Relationship Between Social Marginalization and Obesity

Science.gov (United States)

Apolloni, Andrea; Marathe, Achla; Pan, Zhengzheng

We use 3 Waves of the Add Health data collected between 1994 and 2002 to conduct a longitudinal study of the relationship between social marginalization and the weight status of adolescents and young adults. Past studies have shown that overweight and obese children are socially marginalized. This research tests (1) if this is true when we account for the sample size of each group, (2) does this phenomenon hold over time and (3) is it obesity or social marginalization that precedes in time. Our results show that when the sample size for each group is considered, the share of friendship is conforming to the size of the group. This conformity seems to increase over time as the population becomes more obese. Finally, we find that obesity precedes social marginalization which lends credence to the notion that obesity causes social marginalization and not vice versa.

No till system of maize and crop-livestock integration

Directory of Open Access Journals (Sweden)

Edmar Eduardo Bassan Mendes

2013-12-01

Full Text Available The aim of this work was to evaluate the implementation of the Integrated Crop-Livestock (ICL in beef cattle farms where the corn was planted directly on the pasture, under no-till system, in the first year. The Crop-Livestock Integration (CLI models evaluated consisted of Brachiaria decumbens pastures intercropped with corn in the no tillage system. However, the evaluated CLI system differed from the usual system because it did not use the conventional tillage in the first year, while the conventional soil preparation and sowing of grass is used by most of the Brazilian farms. The results show that in the first year the period of time spent planting and side-dressing nitrogen   on corn was longer compared to the following years, mainly due to the lack of uniformity of the ground surface, once no conventional tillage was used to prepare the soil and these operations were performed with own implements for direct planting. Therefore, many seeds were placed either very deep or not buried, thus compromising the crop and becoming necessary to replant the corn with a manual planter. From the second year on, even though the conditions were not ideal, the ground surface became more accessible for the sowing and cultivation of corn, after the tillage of the first year. The time spent in most operations performed was longer than usual, especially planting and side-dressing nitrogen on the corn so that the discs did not chop off plants due to the irregularities of the ground surface. Productivity dropped due to the problems already discussed that contributed to a lower income. It is therefore concluded that, under these experimental conditions, the conventional tillage is imperative when implementing the CLI system, even considering the soil management improvements observed from the first to the second year.

A brief introduction to marginal analysis for the micro-economics principles course

OpenAIRE

Burkey, Mark L.

2008-01-01

This brief note provides a simple, yet powerful example of how the marginal cost/marginal benefit principle can be used in everyday life. Using the decision of the optimal choice of speed on the highway, this note was developed for use as one of the first readings in an introductory microeconomics course. It is clear in this demonstration that marginal cost is increasing, while marginal benefit is decreasing, and how the intersection of these two curves shows the optimal choice. In addition, ...

Role of specimen US for predicting resection margin status in breast conserving therapy.

Science.gov (United States)

Moschetta, M; Telegrafo, M; Introna, T; Coi, L; Rella, L; Ranieri, V; Cirili, A; Stabile Ianora, A A; Angelelli, G

2015-01-01

To assess the diagnostic accuracy of specimen ultrasound (US) for predicting resection margin status in women undergoing breast conserving therapy for US-detected cancer, having the histological findings as the reference standard. A total of 132 consecutive patients (age range, 34-87 years; mean, 51 years) underwent breast-conserving surgery for US-detected invasive breast cancer. All surgical specimens underwent US examination. The presence of lesion within the specimen and its distance from the specimen margins were assessed considering a threshold distance between the lesion and specimen margins of 10 mm. US findings were then compared with the pathological ones and specimen US. Sensitivity, specificity, diagnostic accuracy, positive (PPV) and negative predictive values (NPV) for predicting histological margin status were evaluated, having the histological findings as the reference standard. The histological examination detected invasive ductal carcinoma in 96/132 (73%) cases, invasive lobular carcinoma in 32/132 (24%), mucinous carcinoma in 4/132 (3%). The pathological margin analysis revealed 96/132 (73%) negative margins and 36 (27%) close/positive margins. US examination detected all 132 breast lesions within the surgical specimens. 110 (83%) negative margins and 22 (17%) positive margins were found on US. Sensitivity, specificity, diagnostic accuracy, PPV and NPV of 44%, 94%, 80%, 73% and 82%, respectively, were found for specimen US. Specimen US represents a time and cost saving imaging tool for evaluating the presence of US detected-breast lesion within surgical specimen and for predicting the histological margin status.

Patterns of failure for glioblastoma multiforme following limited-margin radiation and concurrent temozolomide

International Nuclear Information System (INIS)

Gebhardt, Brian J; Dobelbower, Michael C; Ennis, William H; Bag, Asim K; Markert, James M; Fiveash, John B

2014-01-01

To analyze patterns of failure in patients with glioblastoma multiforme (GBM) treated with limited-margin radiation therapy and concurrent temozolomide. We hypothesize that patients treated with margins in accordance with Adult Brain Tumor Consortium guidelines (ABTC) will demonstrate patterns of failure consistent with previous series of patients treated with 2–3 cm margins. A retrospective review was performed of patients treated at the University of Alabama at Birmingham for GBM between 2000 and 2011. Ninety-five patients with biopsy-proven disease and documented disease progression after treatment were analyzed. The initial planning target volume includes the T1-enhancing tumor and surrounding edema plus a 1 cm margin. The boost planning target volume includes the T1-enhancing tumor plus a 1 cm margin. The tumors were classified as in-field, marginal, or distant if greater than 80%, 20-80%, or less than 20% of the recurrent volume fell within the 95% isodose line, respectively. The median progression-free survival from the time of diagnosis to documented failure was 8 months (range 3–46). Of the 95 documented recurrences, 77 patients (81%) had an in-field component of treatment failure, 6 (6%) had a marginal component, and 27 (28%) had a distant component. Sixty-three patients (66%) demonstrated in-field only recurrence. The low rate of marginal recurrence suggests that wider margins would have little impact on the pattern of failure, validating the use of limited margins in accordance ABTC guidelines

Whipple Resection: Concordance Between Frozen Section And Permanent Section Diagnosis Of Surgical Margins.

Science.gov (United States)

Bilal, Muhammad; Tariq, Hina; Mamoon, Nadira

2018-01-01

Margin assessment is done in Whipple procedures which are usually performed to resect tumours of head of pancreas and ampullary/periampullary region. Aims and objective of the study are to determine the concordance between frozen sections (FS) and permanent sections (PS) of surgical margins in Whipple resections. It is a retrospective study, from January 2008 to January 2015 (07 years). It includes the specimen with malignancy in final report and for which FS of pancreatic and/or CBD margin(s) were requested. Data was retrieved from Laboratory information system (LIS) database. Of the 41 bile duct margins in cases of ampullary tumours, 03 were positive on FS as well as PS, 35 were negative on FS as well as on PS. Results showed 100% sensitivity, 92.1% specificity, 50% PPV and 100% NPV. Results of 36 pancreatic margins in cases of ampullary showed 100% sensitivity, 97.1% specificity, 50% PPV and 100% NPV. In pancreatic carcinoma cases, none of CBD margins were reported as positive on FS, 02 margins reported as negative were found positive on PS, while 17 were negative on FS as well as PS. Results showed 100% specificity and 89.5% NPV. Of the 27 pancreatic margins tested in pancreatic tumours 100% sensitivity, 94.1% specificity, 88.9% PPV and 100% NPV was found. Factors such as absent prior tissue diagnosis and/or inflammatory processes make margin diagnosis difficult. However, a high concordance was observed between our FS and PS diagnosis.

Atlantic continental margin of the United States

Science.gov (United States)

Grow, John A.; Sheridan, Robert E.; Palmer, A.R.

1982-01-01

The objective of this Decade of North American Geology (D-NAG) volume will be to focus on the Mesozoic and Cenozoic evolution of the U.S. Atlantic continental margin, including the onshore coastal plain, related onshore Triassic-Jurassic rift grabens, and the offshore basins and platforms. Following multiple compressional tectonic episodes between Africa and North America during the Paleozoic Era that formed the Appalachian Mountains, the Mesozoic and Cenozoic Eras were dominated by tensional tectonic processes that separated Africa and North America. Extensional rifting during Triassic and Early Jurassic times resulted in numerous tensional grabens both onshore and offshore, which filled with nonmarine continental red beds, lacustrine deposits, and volcanic flows and debris. The final stage of this breakup between Africa and North America occurred beneath the present outer continental shelf and continental slope during Early or Middle Jurassic time when sea-floor spreading began to form new oceanic crust and lithosophere between the two continents as they drifted apart. Postrift subsidence of the marginal basins continued in response to cooling of the lithosphere and sedimentary loading.Geophysical surveys and oil-exploration drilling along the U.S. Atlantic continental margin during the past 5 years are beginning to answer many questions concerning its deep structure and stratigraphy and how it evolved during the rifting and early sea-floor-spreading stages of the separation of this region from Africa. Earlier geophysical studies of the U.S. continental margin used marine refraction and submarine gravity measurements. Single-channel seismic-reflection, marine magnetic, aeromagnetic, and continuous gravity measurements became available during the 1960s.

SU-F-BRD-07: Empirical Derivation of Site-Specific Margin Formulas

International Nuclear Information System (INIS)

Conroy, L; Smith, W; Quirk, S

2014-01-01

Purpose: To empirically derive margin formulas from existing clinical radiotherapy plans accounting for respiratory motion and setup uncertainties. Methods: We simulated realistic treatment scenarios, including respiratory motion and setup errors. Individual probability density functions (PDF) from respiratory data were used to simulate respiratory motion. Random (σ) and systematic (Σ) setup errors were modeled as Gaussian distributions. One-dimensional dose profiles were extracted from existing radiotherapy plans and convolved with respiratory PDFs and random error distributions to produce blurred dose profiles. Each blurred dose profile was then shifted 1000 times by randomly sampling the simulated systematic error distribution. Margins were determined from the distance between the simulated treatment and the original 95% isodose level. An equation was fit for each (σ, Σ) combination to derive margin formulas for 90% of the population receiving 95% dose. This methodology can be applied to different tumor sites. Here, dose profiles were extracted from partial breast 3DCRT plans in the anterior-posterior (AP) and superior-inferior (SI) directions. Respiratory motion data was from healthy volunteers, and a clinically relevant range of random and systematic setup errors (standard deviations 1 – 4 mm) was determined from the literature. Results: The PBI margin formulas in the AP and SI directions for 95% dose coverage for 90% of the population were very similar: M= 0.68σ + 1.54Σ and M= 0.72σ + 1.50Σ, respectively. Systematic setup errors had the largest influence on required margin size, whereas realistic respiratory amplitude had minimal impact. The derived formulas resulted in a smaller systematic component than commonly-used theoretical margin recipes. Conclusion: We have demonstrated a method to derive empirical margin formulas from existing patient radiotherapy plans, incorporating realistic respiratory motion and appropriate ranges of random and

Deoxycholic Acid and the Marginal Mandibular Nerve: A Cadaver Study.

Science.gov (United States)

Blandford, Alexander D; Ansari, Waseem; Young, Jason M; Maley, Bruce; Plesec, Thomas P; Hwang, Catherine J; Perry, Julian D

2018-06-04

One of the rare but serious complications observed with deoxycholic acid administration is damage to the marginal mandibular nerve. In this study, we evaluated if deoxycholic acid directly induces histologic damage to fresh cadaveric marginal mandibular nerve. A segment of marginal mandibular nerve was harvested from 12 hemifaces of 6 fresh cadavers. The nerve specimen was exposed to either 0.9% sterile saline for 24 h, deoxycholic acid (10 mg/ml) for 20 min, or deoxycholic acid (10 mg/ml) for 24 h. The nerve specimens were then fixed in glutaraldehyde for a minimum of 24 h. Toluidine blue stained sections were evaluated for stain intensity using light microscopy and color deconvolution image analysis. Supraplatysmal fat was harvested as a positive control and exposed to the same treatments as the marginal mandibular nerve specimens, then evaluated using transmission electron microscopy. Toluidine blue staining was less in the marginal mandibular nerve exposed to deoxycholic acid when compared to saline. The specimen exposed to deoxycholic acid for 24 h showed less toluidine blue staining than that of the nerve exposed to deoxycholic acid for 20 min. Transmission electron microscopy of submental fat exposed to deoxycholic acid revealed disruption of adipocyte cell membrane integrity and loss of cellular organelles when compared to specimens only exposed to saline. Deoxycholic acid (10 mg/ml) damages the marginal mandibular nerve myelin sheath in fresh human cadaver specimens. Direct deoxycholic acid neurotoxicity may cause marginal mandibular nerve injury clinically. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

The stability margin of elongated plasmas

International Nuclear Information System (INIS)

Portone, Alfredo

2005-01-01

Passive stabilization is a key feature in tokamak design since it indicates the efficiency of the metallic structures to 'oppose' plasma displacements. As far as plasma vertical displacement modes are concerned, usually their passive stabilization is characterized in terms of two main indices, namely the instability growth time and the stability margin. In this study-after recalling the governing equations-we extend the definition of the stability margin given in the literature (Lazarus E. et al 1990 Nucl. Fusion 30 111, Albanese R. et al 1990 IEEE Trans. Magn. 26, Kameari A. et al 1985 Nucl. Eng. Des./Fusion 365-73) for the rigid body displacement model to the non-rigid plasma model. Numerical examples are also given for the reduced task objectives/reduced cost ITER design

Seismic margin analysis technique for nuclear power plant structures

International Nuclear Information System (INIS)

Seo, Jeong Moon; Choi, In Kil

2001-04-01

In general, the Seismic Probabilistic Risk Assessment (SPRA) and the Seismic Margin Assessment(SAM) are used for the evaluation of realistic seismic capacity of nuclear power plant structures. Seismic PRA is a systematic process to evaluate the seismic safety of nuclear power plant. In our country, SPRA has been used to perform the probabilistic safety assessment for the earthquake event. SMA is a simple and cost effective manner to quantify the seismic margin of individual structural elements. This study was performed to improve the reliability of SMA results and to confirm the assessment procedure. To achieve this goal, review for the current status of the techniques and procedures was performed. Two methodologies, CDFM (Conservative Deterministic Failure Margin) sponsored by NRC and FA (Fragility Analysis) sponsored by EPRI, were developed for the seismic margin review of NPP structures. FA method was originally developed for Seismic PRA. CDFM approach is more amenable to use by experienced design engineers including utility staff design engineers. In this study, detailed review on the procedures of CDFM and FA methodology was performed

Determinants of the net interest margins in BH banks

Directory of Open Access Journals (Sweden)

Plakalović Novo

2015-01-01

Full Text Available In this paper, the subject of analysis is influence of certain macroeconomic and microeconomic variables on bank net interest margins in Bosnia and Herzegovina (BH for the period from 2008 to 2013 through a multiple linear regression models. The level and dynamics of NIM indicate the efficiency of financial intermediation. The observed period is characterized by the reduction in net interest margins of banks over the previous decade, which was characterized by high GDP growth, bank loans and high-interest rates and high profitability. Therefore, this study examines the factors that affect the level of net interest margins in the domestic banking industry. The main objective of this paper is to determine whether there is interdependence in the movement between the independent and dependent variables through a multiple linear regression. The net interest margin will be observed as a dependent variable, and liquidity risk, operating costs, credit risk, the index of market concentration, funding risk, the growth rate of gross domestic product and consumer price index will be used as independent variables.

A simple model for enamel fracture from margin cracks.

Science.gov (United States)

Chai, Herzl; Lee, James J-W; Kwon, Jae-Young; Lucas, Peter W; Lawn, Brian R

2009-06-01

We present results of in situ fracture tests on extracted human molar teeth showing failure by margin cracking. The teeth are mounted into an epoxy base and loaded with a rod indenter capped with a Teflon insert, as representative of food modulus. In situ observations of cracks extending longitudinally upward from the cervical margins are recorded in real time with a video camera. The cracks appear above some threshold and grow steadily within the enamel coat toward the occlusal surface in a configuration reminiscent of channel-like cracks in brittle films. Substantially higher loading is required to delaminate the enamel from the dentin, attesting to the resilience of the tooth structure. A simplistic fracture mechanics analysis is applied to determine the critical load relation for traversal of the margin crack along the full length of the side wall. The capacity of any given tooth to resist failure by margin cracking is predicted to increase with greater enamel thickness and cuspal radius. Implications in relation to dentistry and evolutionary biology are briefly considered.

“Marginal land” for energy crops: Exploring definitions and embedded assumptions

International Nuclear Information System (INIS)

Shortall, O.K.

2013-01-01

The idea of using less productive or “marginal land” for energy crops is promoted as a way to overcome the previous land use controversies faced by biofuels. It is argued that marginal land use would not compete with food production, is widely available and would incur fewer environmental impacts. This term is notoriously vague however, as are the details of how marginal land use for energy crops would work in practice. This paper explores definitions of the term “marginal land” in academic, consultancy, NGO, government and industry documents in the UK. It identifies three separate definitions of the term: land unsuitable for food production; ambiguous lower quality land; and economically marginal land. It probes these definitions further by exploring the technical, normative and political assumptions embedded within them. It finds that the first two definitions are normatively motivated: this land should be used to overcome controversies and the latter definition is predictive: this land is likely to be used. It is important that the different advantages, disadvantages and implications of the definitions are spelled out so definitions are not conflated to create unrealistic expectations about the role of marginal land in overcoming biofuels land use controversies. -- Highlights: •Qualitative methods were used to explore definitions of the term “marginal land”. •Three definitions were identified. •Two definitions focus on overcoming biomass land use controversies. •One definition predicts what land will be used for growing biomass. •Definitions contain problematic assumptions

Marginality and Variability in Esperanto.

Science.gov (United States)

Brent, Edmund

This paper discusses Esperanto as a planned language and refutes three myths connected to it, namely, that Esperanto is achronical, atopical, and apragmatic. The focus here is on a synchronic analysis. Synchronic variability is studied with reference to the structuralist determination of "marginality" and the dynamic linguistic…

Pushing the Margins of Responsibility

DEFF Research Database (Denmark)

Santoni de Sio, Filippo; Di Nucci, Ezio

2018-01-01

David Shoemaker has claimed that a binary approach to moral responsibility leaves out something important, namely instances of marginal agency, cases where agents seem to be eligible for some responsibility responses but not others. In this paper we endorse and extend Shoemaker’s approach by pres...

Contrasting evidence of Holocene ice margin retreat, south-western Greenland

DEFF Research Database (Denmark)

Levy, L. B.; Larsen, N. K.; Davidson, T. A.

2017-01-01

Constraining the Greenland Ice Sheet's (GrIS) response to Holocene climate change provides calibrations for ice sheet models that hindcast past ice margin fluctuations. Ice sheet models predict enhanced ice retreat in south-western Greenland during the middle Holocene; however, few geological...... observations corroborating the extensive retreat are available. We present new data from lake sediment cores from the Isua region, south-western Greenland, which provide constraints on Holocene fluctuations of the GrIS margins. Our data indicate that the main GrIS margin was 30 km west of its present...

Impact of no-till cover cropping of Italian ryegrass on above and below ground faunal communities inhabiting a soybean field with special emphasis on soybean cyst nematodes

Science.gov (United States)

Two field trials were conducted in Maryland to evaluate the ability of an Italian ryegrass (IR) (Lolium multiflorum) cover crop in a no-till soybean (Glycine max) planting to 1) reduce populations of plant-parasitic nematodes (i.e., the soybean cyst nematode, Heterodera glycines and lesion nematodes...

Analysis of safety margins for PuO2 containers

International Nuclear Information System (INIS)

Hubert, P.; Tomachevsky, E.

1987-11-01

In the regular manner the containers for PuO 2 transport are type B(U) and give satisfaction to the AIEA proofs. However the vigour of this conception's containers and the analysis of other radioactive containers permit to think that large safety margins exist. In this paper, the importance and the kind of these margins are studied [fr

Extensive management of field margins enhances their potential for off-site soil erosion mitigation.

Science.gov (United States)

Ali, Hamada E; Reineking, Björn

2016-03-15

Soil erosion is a widespread problem in agricultural landscapes, particularly in regions with strong rainfall events. Vegetated field margins can mitigate negative impacts of soil erosion off-site by trapping eroded material. Here we analyse how local management affects the trapping capacity of field margins in a monsoon region of South Korea, contrasting intensively and extensively managed field margins on both steep and shallow slopes. Prior to the beginning of monsoon season, we equipped a total of 12 sites representing three replicates for each of four different types of field margins ("intensive managed flat", "intensive managed steep", "extensive managed flat" and "extensive managed steep") with Astroturf mats. The mats (n = 15/site) were placed before, within and after the field margin. Sediment was collected after each rain event until the end of the monsoon season. The effect of management and slope on sediment trapping was analysed using linear mixed effects models, using as response variable either the sediment collected within the field margin or the difference in sediment collected after and before the field margin. There was no difference in the amount of sediment reaching the different field margin types. In contrast, extensively managed field margins showed a large reduction in collected sediment before and after the field margins. This effect was pronounced in steep field margins, and increased with the size of rainfall events. We conclude that a field margin management promoting a dense vegetation cover is a key to mitigating negative off-site effects of soil erosion in monsoon regions, particularly in field margins with steep slopes. Copyright © 2015 Elsevier Ltd. All rights reserved.

Hummocky moraine: sedimentary record of stagnant Laurentide Ice Sheet lobes resting on soft beds

Science.gov (United States)

Eyles, N.; Boyce, J. I.; Barendregt, R. W.

1999-02-01

Over large areas of the western interior plains of North America, hummocky moraine (HM) formed at the margins of Laurentide Ice Sheet (LIS) lobes that flowed upslope against topographic highs. Current depositional models argue that HM was deposited supraglacially from stagnant debris-rich ice (`disintegration moraine'). Across southern Alberta, Canada, map and outcrop data show that HM is composed of fine-grained till as much as 25 m thick containing rafts of soft, glaciotectonized bedrock and sediment. Chaotic, non-oriented HM commonly passes downslope into weakly-oriented hummocks (`washboard moraine') that are transitional to drumlins in topographic lows; the same subsurface stratigraphy and till facies is present throughout. These landforms, and others such as doughnut-like `rim ridges', flat-topped `moraine plateaux' and linear disintegration ridges, are identified as belonging to subglacially-deposited soft-bed terrain. This terrain is the record of ice lobes moving over deformation till derived from weakly-lithified, bentonite-rich shale. Drumlins record continued active ice flow in topographic lows during deglaciation whereas HM was produced below the outer stagnant margins of ice lobes by gravitational loading (`pressing') of remnant dead ice blocks into wet, plastic till. Intervening zones of washboard moraine mark the former boundary of active and stagnant ice and show `hybrid' drumlins whose streamlined form has been altered by subglacial pressing (` humdrums') below dead ice. The presence of hummocky moraine over a very large area of interior North America provides additional support for glaciological models of a soft-bedded Laurentide Ice Sheet.

Mapping Mesophotic Reefs Along the Brazilian Continental Margin

Science.gov (United States)

Bastos, A.; Moura, R.; Amado Filho, G.; Ferreira, L.; Boni, G.; Vedoato, F.; D'Agostini, D.; Lavagnino, A. C.; Leite, M. D.; Quaresma, V.

2017-12-01

Submerged or drowned reefs constitute an important geological record of sea level variations, forming the substrate for the colonization of modern benthic mesophotic communities. Although mapping mesophotic reefs has increased in the last years, their spatial distribution is poorly known and the worldwide occurrence of this reef habitat maybe underestimated. The importance in recognizing the distribution of mesophotic reefs is that they can act as a refuge for corals during unsuitable environmental conditions and a repository for shallow water corals. Here we present the result of several acoustic surveys that mapped and discovered new mesophotic reefs along the Eastern and Equatorial Brazilian Continental Margin. Seabed mapping was carried out using multibeam and side scan sonars. Ground truthing was obtained using drop camera or scuba diving. Mesophotic reefs were mapped in water depths varying from 30 to 100m and under distinct oceanographic conditions, especially in terms of river load input and shelf width. Reefs showed distinct morphologies, from low relief banks and paleovalleys to shelf edge ridges. Extensive occurrence of low relief banks were mapped along the most important coralline complex province in the South Atlantic, the Abrolhos Shelf. These 30 to 40m deep banks, have no more than 3 meters in height and may represent fringing reefs formed during sea level stabilization. Paleovalleys mapped along the eastern margin showed the occurrence of coralgal ledges along the channel margins. Paleovalleys are usually deeper than 45m and are associated with outer shelf rhodolith beds. Shelf edge ridges (80 to 120m deep) were mapped along both margins and are related to red algal encrusting irregular surfaces that have more than 3m in height, forming a rigid substrate for coral growth. Along the Equatorial Margin, off the Amazon mouth, shelf edge patch reefs and rhodolith beds forming encrusting surfaces and shelf edge ridges were mapped in water depths greater

In vitro evaluation of marginal adaptation in five ceramic restoration fabricating techniques.

Science.gov (United States)

Ural, Cağri; Burgaz, Yavuz; Saraç, Duygu

2010-01-01

To compare in vitro the marginal adaptation of crowns manufactured using ceramic restoration fabricating techniques. Fifty standardized master steel dies simulating molars were produced and divided into five groups, each containing 10 specimens. Test specimens were fabricated with CAD/CAM, heat-press, glass-infiltration, and conventional lost-wax techniques according to manufacturer instructions. Marginal adaptation of the test specimens was measured vertically before and after cementation using SEM. Data were statistically analyzed by one-way ANOVA with Tukey HSD tests (a = .05). Marginal adaptation of ceramic crowns was affected by fabrication technique and cementation process (P cementation (P cementation. Marginal adaptation values obtained in the compared systems were within clinically acceptable limits. Cementation causes a significant increase in the vertical marginal discrepancies of the test specimens.

City and sea margins. Porto’s Marginal as scale and measure of new spaces

Directory of Open Access Journals (Sweden)

Giuseppe Parità

2014-06-01

Full Text Available The city has always been confronting with its own end and the beginning of the water system. Among the different kind of margin areas, the ones that border the cities on their watersides are particularly interesting. These new liminal territories are rich in variety and differences and are set up of several elements made of different morphologies that should be carefully read and interpreted: the need of re-thinking the morphological elements that mark an urban edge leads to the identification of several shapes and forms of the water borderlands. Borders, limits, boundaries, edges, margin areas - usually considered as an obstacle to the construction of the city - turn themselves as new possible “design materials” for building that ambiguous distance between city and the sea. The article aims to focus on the case-study of Porto’s Marginal that well explain how many ways a city can live its water edges. On a large scale, it is configured as a strip of 15 kilometers of public space. Within this continuity, the different extent of the distance between city and water leads to reflect on the different types of relationships (and therefore projects between the end of one side and the beginning of another. For Porto, those are not only urban parts, but also different geographical parts (sea, rivers, topography that distance puts in relation through the design sometimes of the line, at time of the border or of a surface. So, the analysis of these heterogeneous but continuous projects aim to focus on the several techniques of urban composition to build contemporary public spaces. On one hand they give form to a continuous “public figure”, on the other hand each one of the project can be considered as part of a “atlas” of liminal places, giving form to public spaces. 

Ecological and evolutionary processes at expanding range margins

OpenAIRE

Thomas, C.D.; Bodsworth, E.J.; Wilson, R.J.; Simmons, A.D.; Davies, Z.G.; Musche, M.; Conradt, L.

2001-01-01

Many animals are regarded as relatively sedentary and specialized in marginal parts of their geographical distributions. They are expected to be slow at colonizing new habitats. Despite this, the cool margins of many species' distributions have expanded\\ud rapidly in association with recent climate warming3±10. We examined four insect species that have expanded their geographical\\ud ranges in Britain over the past 20 years. Here we report that two butterfly species have increased the variety ...

Contributions to knowledge of the continental margin of Uruguay. Uruguayan continental margin: morphology, geology and identification of the base of the slope

International Nuclear Information System (INIS)

Preciozzi, F.

2014-01-01

This work is about the morphology, geology and the identification of the base of the slope in the The Uruguayan continental margin which corresponds to the the type of divergent, volcanic and segmented margins. Morphologically is constituted by a clearly defined continental shelf, as well as a continental slope that presents configuration changes from north to south and passes directly to the abyssal plain

A comparison of pay-as-bid and marginal pricing in electricity markets

Science.gov (United States)

Ren, Yongjun

This thesis investigates the behaviour of electricity markets under marginal and pay-as-bid pricing. Marginal pricing is believed to yield the maximum social welfare and is currently implemented by most electricity markets. However, in view of recent electricity market failures, pay-as-bid has been extensively discussed as a possible alternative to marginal pricing. In this research, marginal and pay-as-bid pricing have been analyzed in electricity markets with both perfect and imperfect competition. The perfect competition case is studied under both exact and uncertain system marginal cost prediction. The comparison of the two pricing methods is conducted through two steps: (i) identify the best offer strategy of the generating companies (gencos); (ii) analyze the market performance under these optimum genco strategies. The analysis results together with numerical simulations show that pay-as-bid and marginal pricing are equivalent in a perfect market with exact system marginal cost prediction. In perfect markets with uncertain demand prediction, the two pricing methods are also equivalent but in an expected value sense. If we compare from the perspective of second order statistics, all market performance measures exhibit much lower values under pay-as-bid than under marginal pricing. The risk of deviating from the mean is therefore much higher under marginal pricing than under pay-as-bid. In an imperfect competition market with exact demand prediction, the research shows that pay-as-bid pricing yields lower consumer payments and lower genco profits. This research provides quantitative evidence that challenges some common claims about pay-as-bid pricing. One is that under pay-as-bid, participants would soon learn how to offer so as to obtain the same or higher profits than what they would have obtained under marginal pricing. This research however shows that, under pay-as-bid, participants can at best earn the same profit or expected profit as under marginal

Maximum Margin Clustering of Hyperspectral Data

Science.gov (United States)

Niazmardi, S.; Safari, A.; Homayouni, S.

2013-09-01

In recent decades, large margin methods such as Support Vector Machines (SVMs) are supposed to be the state-of-the-art of supervised learning methods for classification of hyperspectral data. However, the results of these algorithms mainly depend on the quality and quantity of available training data. To tackle down the problems associated with the training data, the researcher put effort into extending the capability of large margin algorithms for unsupervised learning. One of the recent proposed algorithms is Maximum Margin Clustering (MMC). The MMC is an unsupervised SVMs algorithm that simultaneously estimates both the labels and the hyperplane parameters. Nevertheless, the optimization of the MMC algorithm is a non-convex problem. Most of the existing MMC methods rely on the reformulating and the relaxing of the non-convex optimization problem as semi-definite programs (SDP), which are computationally very expensive and only can handle small data sets. Moreover, most of these algorithms are two-class classification, which cannot be used for classification of remotely sensed data. In this paper, a new MMC algorithm is used that solve the original non-convex problem using Alternative Optimization method. This algorithm is also extended for multi-class classification and its performance is evaluated. The results of the proposed algorithm show that the algorithm has acceptable results for hyperspectral data clustering.

Profit margins in Japanese retailing

NARCIS (Netherlands)

J.C.A. Potjes; A.R. Thurik (Roy)

1993-01-01

textabstractUsing a rich data source, we explain differences and developments in profit margins of medium-sized stores in Japan. We conclude that the protected environment enables the retailer to pass on all operating costs to the customers and to obtain a relatively high basic income. High service

Influence of radiation dose on positive surgical margins in women undergoing breast conservation therapy

International Nuclear Information System (INIS)

DiBiase, Steven J.; Komarnicky, Lydia T.; Heron, Dwight E.; Schwartz, Gordon F.; Mansfield, Carl M.

2002-01-01

Purpose: Positive surgical margins adversely influence local tumor control in breast conservation therapy (BCT). However, reports have conflicted regarding whether an increased radiation dose can overcome this poor prognostic factor. In this study, we evaluated the influence of an increased radiation dose on tumor control in women with positive surgical margins undergoing BCT. Methods and Materials: Between 1978 and 1994, 733 women with pathologic Stage I-II breast cancer and known surgical margin status were treated at Thomas Jefferson University Hospital with BCT. Of these 733 patients, 641 women had a minimal tumor bed dose of 60 Gy and had documentation of their margin status; 509 had negative surgical margins, and 132 had positive surgical margins before definitive radiotherapy. Complete gross excision of the tumor and axillary lymph node sampling was obtained in all patients. The median radiation dose to the primary site was 65.0 Gy (range 60-76). Of the women with positive margins (n=132), the influence of higher doses of radiotherapy was evaluated. The median follow-up time was 52 months. Results: The local tumor control rate for patients with negative margins at 5 and 10 years was 94% and 88%, respectively, compared with 85% and 67%, respectively, for those women with positive margins (p=0.001). The disease-free survival rate for the negative margin group at 5 and 10 years was 91% and 82%, respectively, compared with 76% and 71%, respectively, for the positive margin group (p = 0.001). The overall survival rate of women with negative margins at 5 and 10 years was 95% and 90%, respectively. By comparison, for women with positive surgical margins, the overall survival rate at 5 and 10 years was 86% and 79%, respectively (p=0.008). A comparison of the positive and negative margin groups revealed that an increased radiation dose (whether entered as a dichotomous or a continuous variable) >65.0 Gy did not improve local tumor control (p=0.776). On Cox

Terraced margins of inflated lava flows on Earth and Mars

Science.gov (United States)

Zimbelman, J. R.; Garry, W. B.; Bleacher, J. E.; Crumpler, L. S.

2011-12-01

When fluid basaltic lava flows are emplaced over a shallow regional slope (typically much less than one degree), the lava flows often display impressive characteristics of inflation. Here we describe a distinctive marginal characteristic that is often developed along the margins of endogenously inflated basaltic lava flows; discreet topographic levels of the emplaced lava that are here termed 'terraced margins'. Terraced margins were first noted at the distal end of the Carrizozo lava flow in central New Mexico, where they are particularly well expressed, but terraces have also been observed along some margins of the McCartys lava flow (NM), the distal end of the 1859 Mauna Loa lava flow (HI), and lava flows at Craters of the Moon (ID). Differential Global Positioning System surveys across several terraced margins reveal consistent topographic characteristics: the upper surface of each terrace level is at roughly one half the height of the sheet lobe from which it emerges; when a terrace becomes the source of an additional outbreak, the upper surface of the second terrace is at roughly one half the height of the source terrace; often a subtle topographic depression is present along the contact between a terrace and its source sheet lobe, suggesting that the terrace outflow starts at a level roughly one-third the height of the source lobe; the upper surfaces of both the source sheet lobe and associated terraces are level to within tens of centimeters across length scales of many tens to hundreds of meters, indicative of inflation of all components. The field observations will be used as the constraints for modeling of the inflation and terracing mechanisms, an effort that has only recently started. The multiple imaging data sets now available for Mars have revealed the presence of terraced margins on some lava flows on Mars. Although detailed topographic data are not currently available for the Martian examples identified so far, the presence of terraced margins for

Compressibility of Oxisol aggregates under no-till in response to soil water potential Compressibilidade de agregados de Latossolo Vermelho sob plantio direto em resposta ao potencial da água do solo

Directory of Open Access Journals (Sweden)

João Tavares Filho

2009-12-01

Full Text Available The system of no-till sowing stands out as being a technology that suits the objectives of more rational use of the soil and greater protection against the erosion. However, through till, any of it, occurs modifications of the soil's structure. This current work aims to study the influence of the energy state of the water and of the organic matter on the mechanism of compaction of Red Oxisol under no-till management system. Humid and non-deformed sample were collected in horizon AP of two agricultural areas under no-till, with and without rotation of cultures. In the laboratory, these samples were broken into fragments and sifted to obtain aggregates of 4 to 5 mm sized, which were placed in equilibrium under four matrix potentials. Thereafter, they were exposed to uni-dimensional compression with pressures varying from 32 to 1,000 kPa. The results in such a way show that the highest compressibility of aggregates both for the tilling with rotation of cultures as for the tilling without rotation of cultures, occurred for matrix potential -32 kPa (humidity of 0.29-0.32 kg kg-1, respectively, while the minor occurred for the potentials of -1 and -1,000 kPa (humidity of 0.35 and 0.27 kg kg-1, respectively, indicating that this soil should not be worked with humidity ranging around 0.29 to 0.32 kg kg-1 and the highest reduction of volume of aggregates was obtained for the mechanical pressures lower than 600 inferior kPa, indicating that these soils showed to be very influenced by compression, when exposed to mechanical work. Also, the aggregates of soil under no-till and rotation of crops presented higher sensitivity to the compression than the aggregates of soil under no-till and without rotation of crops, possibly for having better structural conditions given to a higher content of organic matter.O sistema de semeadura direta destaca-se como uma tecnologia que atende aos objetivos de uso mais racional do solo e maior proteção contra a eros

Nonlinear dynamics near the stability margin in rotating pipe flow

Science.gov (United States)

Yang, Z.; Leibovich, S.

1991-01-01

The nonlinear evolution of marginally unstable wave packets in rotating pipe flow is studied. These flows depend on two control parameters, which may be taken to be the axial Reynolds number R and a Rossby number, q. Marginal stability is realized on a curve in the (R, q)-plane, and the entire marginal stability boundary is explored. As the flow passes through any point on the marginal stability curve, it undergoes a supercritical Hopf bifurcation and the steady base flow is replaced by a traveling wave. The envelope of the wave system is governed by a complex Ginzburg-Landau equation. The Ginzburg-Landau equation admits Stokes waves, which correspond to standing modulations of the linear traveling wavetrain, as well as traveling wave modulations of the linear wavetrain. Bands of wavenumbers are identified in which the nonlinear modulated waves are subject to a sideband instability.

Centrifugal Compressor Surge Margin Improved With Diffuser Hub Surface Air Injection

Science.gov (United States)

Skoch, Gary J.

2002-01-01

Aerodynamic stability is an important parameter in the design of compressors for aircraft gas turbine engines. Compression system instabilities can cause compressor surge, which may lead to the loss of an aircraft. As a result, engine designers include a margin of safety between the operating line of the engine and the stability limit line of the compressor. The margin of safety is typically referred to as "surge margin." Achieving the highest possible level of surge margin while meeting design point performance objectives is the goal of the compressor designer. However, performance goals often must be compromised in order to achieve adequate levels of surge margin. Techniques to improve surge margin will permit more aggressive compressor designs. Centrifugal compressor surge margin improvement was demonstrated at the NASA Glenn Research Center by injecting air into the vaned diffuser of a 4:1-pressure-ratio centrifugal compressor. Tests were performed using injector nozzles located on the diffuser hub surface of a vane-island diffuser in the vaneless region between the impeller trailing edge and the diffuser-vane leading edge. The nozzle flow path and discharge shape were designed to produce an air stream that remained tangent to the hub surface as it traveled into the diffuser passage. Injector nozzles were located near the leading edge of 23 of the 24 diffuser vanes. One passage did not contain an injector so that instrumentation located in that passage would be preserved. Several orientations of the injected stream relative to the diffuser vane leading edge were tested over a range of injected flow rates. Only steady flow (nonpulsed) air injection was tested. At 100 percent of the design speed, a 15-percent improvement in the baseline surge margin was achieved with a nozzle orientation that produced a jet that was bisected by the diffuser vane leading edge. Other orientations also improved the baseline surge margin. Tests were conducted at speeds below the

Impact of organ shape variations on margin concepts for cervix cancer ART.

Science.gov (United States)

Seppenwoolde, Yvette; Stock, Markus; Buschmann, Martin; Georg, Dietmar; Bauer-Novotny, Kwei-Yuang; Pötter, Richard; Georg, Petra

2016-09-01

Target and organ movement motivate adaptive radiotherapy for cervix cancer patients. We investigated the dosimetric impact of margin concepts with different levels of complexity on both organ at risk (OAR) sparing and PTV coverage. Weekly CT and daily CBCT scans were delineated for 10 patients. The dosimetric impact of organ shape variations were evaluated for four (isotropic) margin concepts: two static PTVs (PTV 6mm and PTV 15mm ), a PTV based on ITV of the planning CT and CBCTs of the first treatment week (PTV ART ITV ) and an adaptive PTV based on a library approach (PTV ART Library ). Using static concepts, OAR doses increased with large margins, while smaller margins compromised target coverage. ART PTVs resulted in comparable target coverage and better sparing of bladder (V40Gy: 15% and 7% less), rectum (V40Gy: 18 and 6cc less) and bowel (V40Gy: 106 and 15cc less) compared to PTV 15mm . Target coverage evaluation showed that for elective fields a static 5mm margin sufficed. PTV ART Library achieved the best dosimetric results. However when weighing clinical benefit against workload, ITV margins based on repetitive movement evaluation during the first week also provide improvements over static margin concepts. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Middlemen Margins and Globalization

OpenAIRE

Pranab Bardhan; Dilip Mookherjee; Masatoshi Tsumagari

2013-01-01

We develop a theory of trading middlemen or entrepreneurs who perform financing, quality supervision and marketing roles for goods produced by suppliers or workers. Brand-name reputations are necessary to overcome product quality moral hazard problems; middlemen margins represent reputational incentive rents. We develop a two sector North-South model of competitive equilibrium, with endogenous sorting of agents with heterogenous entrepreneurial abilities into sectors and occupations. The Sout...

Export Margins, Price and Quantity of Belarus’s Export Growth

Directory of Open Access Journals (Sweden)

Otamurodov Shavkat

2017-03-01

Full Text Available This paper examines the sources of Belarus’s export growth and decomposes export growth into extensive and intensive margins. This study also aims to determine export margins for intermediate and final goods and to determine the price and quantity components of the intensive export margin. In order to achieve the desired objectives, we use two methods for decomposing export growth, the count method and the export shares method. We analyse Belarus's export growth using export data at the HS-6 digit level for the 2004-2014 period. Our results show that Belarus's exports grew mainly due to growth in the price margin during the studied period 2004-2014. However, the extensive margin was important in export growth to some extent. Comparing the growth rate across final and intermediate goods reveals that although the share of final products in Belarus’s exports is not very big (18.9% in 2014, the average annual growth in exports of final products is higher than that of intermediate goods. Our investigation also shows that Belarus produces a wide range of commodities, but the share of the most of these commodities is not large; its exports depend on a restricted range of commodities. Moreover, most of the commodities are exported to Russia and Ukraine. Our results give us reason to assume that finding new markets for their new products is one of the main challenges for developing countries wishing to increase their exports by an extensive margin. This has important implications for how policy makers promote the trade and diversification of exports.

Effect of two prophylaxis methods on marginal gap of Cl Vresin-modified glass-ionomer restorations.

Science.gov (United States)

Kimyai, Soodabeh; Pournaghi-Azar, Fatemeh; Daneshpooy, Mehdi; Abed Kahnamoii, Mehdi; Davoodi, Farnaz

2016-01-01

Background. This study evaluated the effect of two prophylaxis techniques on the marginal gap of CI V resin-modified glass-ionomer restorations. Methods. Standard Cl V cavities were prepared on the buccal surfaces of 48 sound bovine mandibular incisors in this in vitro study. After restoration of the cavities with GC Fuji II LC resin-modified glass-ionomer, the samples were randomly assigned to 3 groups of 16. In group 1, the prophylactic procedures were carried out with rubber cup and pumice powder and in group 2 with air-powder polishing device (APD). In group 3 (control), the samples did not undergo any prophylactic procedures. Then the marginal gaps were measured. Two-way ANOVA was used to compare marginal gaps at the occlusal and gingival margins between the groups. Post hoc Tukey test was used for two-by-two comparisons. Statistical significance was set at P marginal gaps in terms of prophylactic techniques (P marginal gaps in the APD group compared to the pumice and rubber cup group, which in turn exhibited significantly larger marginal gaps compared to the control group (P marginal gaps were significant in terms of the margin type (P margins compared to the occlusal margins (P marginal gaps of Cl V resin-modified glass-ionomer restorations.

Negotiating autonomy at the margins of the state

DEFF Research Database (Denmark)

Eilenberg, Michael

2009-01-01

Recent processes of decentralization have dramatically changed local political configurations and access to resources throughout Indonesia. In particular, the resource-rich regions at the margins of the state have, in the name of regional autonomy, experienced new spaces for manoeuvre in their cl......Recent processes of decentralization have dramatically changed local political configurations and access to resources throughout Indonesia. In particular, the resource-rich regions at the margins of the state have, in the name of regional autonomy, experienced new spaces for manoeuvre...

Air-Sea Interactions in the Marginal Ice Zone

Science.gov (United States)

2016-03-31

elementascience.org Air-sea interactions in the marginal ice zoneAir-Sea interactions in the Marginal Ice Zone Seth Zippel1* • Jim Thomson1 1Applied...Bidlot, 2013; Collins -III et al., 2015). Spectral wave directions and spread are given in Figure 5, where the difference in wave and wind direction...359219a0. Chalikov DV, Belevich MY. 1993. One-dimensional theory of the wave boundary layer. Bound-Lay Meteor 63: 65–96. Collins -III CO, Rogers WE

Univariate decision tree induction using maximum margin classification

OpenAIRE

Yıldız, Olcay Taner

2012-01-01

In many pattern recognition applications, first decision trees are used due to their simplicity and easily interpretable nature. In this paper, we propose a new decision tree learning algorithm called univariate margin tree where, for each continuous attribute, the best split is found using convex optimization. Our simulation results on 47 data sets show that the novel margin tree classifier performs at least as good as C4.5 and linear discriminant tree (LDT) with a similar time complexity. F...

Excision margin status: does it impact on local control of breast cancer?

International Nuclear Information System (INIS)

Lamoury, G.; Morgan, G.; Ward, R.

2003-01-01

Whilst many patients treated with breast conservation undergo re-excision(s) to obtain clear margins, the relationship between clear margins and local recurrence remains unclear. We aimed to determine the impact of final pathological margin status on local recurrence and other breast cancer outcomes. Our study cohort consisted of 755 consecutive patients treated with breast conservation between January 1984 and December 1995. Pathology reports were available for review in 681subjects (90%). Patients were stratified into 8 groups based on final pathological margin status: 1) negative (>3mm, n = 307), close [further divided into two groups 2) >0 1< 2mm, (n = 67)], 4) positive (n= 79), 5) indeterminate (n= 144), 6) low grade DCIS at the margin (n= 3), 7) high grade DCIS at the margin (n= 23) and 8) LCIS at the margin (n= 4). There were no differences between the groups based on histology, T size, grade, LN positivity or total radiation dose. At a median follow-up of 71 months, the breast relapse free survival (BRFS) was 97%, the distant metastasis free survival (DMFS) 78% and the overall survival (OS) 86%, for the entire cohort. There were no statistically significant differences between the negative, close, and positive groups in terms of BRFS: 96% vs. 94% vs. 93% (p=0.59), MFS: 98% vs. 97% vs. 98% (p=0.87) or OS: 84%vs. 85% vs. 86% (p=0.78). Although not statistically significant, the presence of EIC, in the context of close or positive margins, impacted adversely upon local and overall disease free survival. Patients undergoing breast conservation carry a lifelong risk of local recurrence. It is still not clear whether obtaining a radical margin decreases this risk. Tissue microarray analysis will be performed to further elucidate the causes of ipsilateral recurrence at a molecular and genetic level

Geomorphology and Neogene tectonic evolution of the Palomares continental margin (Western Mediterranean)

Science.gov (United States)

Gómez de la Peña, Laura; Gràcia, Eulàlia; Muñoz, Araceli; Acosta, Juan; Gómez-Ballesteros, María; R. Ranero, César; Uchupi, Elazar

2016-10-01

The Palomares continental margin is located in the southeastern part of Spain. The margin main structure was formed during Miocene times, and it is currently part of the wide deformation zone characterizing the region between the Iberian and African plates, where no well-defined plate boundary occurs. The convergence between these two plates is here accommodated by several structures, including the left lateral strike-slip Palomares Fault. The region is characterized by sparse, low to moderate magnitude (Mw shallow instrumental earthquakes, although large historical events have also occurred. To understand the recent tectonic history of the margin we analyze new high-resolution multibeam bathymetry data and re-processed three multichannel seismic reflection profiles crossing the main structures. The analysis of seafloor morphology and associated subsurface structure provides new insights of the active tectonic features of the area. In contrast to other segments of the southeastern Iberian margin, the Palomares margin contains numerous large and comparatively closely spaced canyons with heads that reach near the coast. The margin relief is also characterized by the presence of three prominent igneous submarine ridges that include the Aguilas, Abubacer and Maimonides highs. Erosive processes evidenced by a number of scars, slope failures, gullies and canyon incisions shape the present-day relief of the Palomares margin. Seismic images reveal the deep structure distinguishing between Miocene structures related to the formation of the margin and currently active features, some of which may reactivate inherited structures. The structure of the margin started with an extensional phase accompanied by volcanic accretion during the Serravallian, followed by a compressional pulse that started during the Latemost Tortonian. Nowadays, tectonic activity offshore is subdued and limited to few, minor faults, in comparison with the activity recorded onshore. The deep Algero

Overview of seismic margin insights gained from seismic PRA results

International Nuclear Information System (INIS)

Kennedy, R.P.; Sues, R.H.; Campbell, R.D.

1986-01-01

This paper presents the findings of a study conducted under NRC and EPRI sponsorship in which published seismic PRAs were reviewed in order to gain insight to the seismic margins inherent in existing nuclear plants. The approach taken was to examine the fragilities of those components which have been found to be dominant contributors to seismic risk at plants in low-to-moderate seismic regions (SSE levels between 0.12g and 0.25g). It is concluded that there is significant margin inherent in the capacity of most critical components above the plant design basis. For ground motions less than about 0.3g, the predominant sources of seismic risk are loss of offsite power coupled with random failure of the emergency diesels, non-recoverable circuit breaker trip due to relay chatter, unanchored equipment, unreinforced non-load bearing block walls, vertical water storage tanks, systems interactions and possibly soil liquefaction. Recommendations as to which components should be reviewed in seismic margin studies for margin earthquakes less than 0.3g, between 0.3g and 0.5g, and greater than 0.5g, developed by the NRC expert panel on the quantification of seismic margins (based on the review of past PRA data, earthquake experience data, and their own personal experience) are presented

Ocean Margins Programs, Phase I research summaries

Energy Technology Data Exchange (ETDEWEB)

Verity, P. [ed.

1994-08-01

During FY 1992, the DOE restructured its regional coastal-ocean programs into a new Ocean Margins Program (OMP), to: Quantify the ecological and biogeochemical processes and mechanisms that affect the cycling, flux, and storage of carbon and other biogenic elements at the land/ocean interface; Define ocean-margin sources and sinks in global biogeochemical cycles, and; Determine whether continental shelves are quantitatively significant in removing carbon dioxide from the atmosphere and isolating it via burial in sediments or export to the interior ocean. Currently, the DOE Ocean Margins Program supports more than 70 principal and co-principal investigators, spanning more than 30 academic institutions. Research funded by the OMP amounted to about $6.9M in FY 1994. This document is a collection of abstracts summarizing the component projects of Phase I of the OMP. This phase included both research and technology development, and comprised projects of both two and three years duration. The attached abstracts describe the goals, methods, measurement scales, strengths and limitations, and status of each project, and level of support. Keywords are provided to index the various projects. The names, addresses, affiliations, and major areas of expertise of the investigators are provided in appendices.

Policy Implementation, Role Conflict and Marginalization

African Journals Online (AJOL)

Prince Acheampong

governance, their role has been politically, administratively, and financially ... of marginalization of the Traditional Systems in terms of legal, financial and ..... the President as the Chief Executive Officer of the district is another controlling factor.

Asymmetric rifting, breakup and magmatism across conjugate margin pairs: insights from Newfoundland to Ireland

Science.gov (United States)

Peace, Alexander L.; Welford, J. Kim; Foulger, Gillian R.; McCaffrey, Ken J. W.

2017-04-01

Continental extension, subsequent rifting and eventual breakup result in the development of passive margins with transitional crust between extended continental crust and newly created oceanic crust. Globally, passive margins are typically classified as either magma-rich or magma-poor. Despite this simple classification, magma-poor margins like the West Orphan Basin, offshore Newfoundland, do exhibit some evidence of localized magmatism, as magmatism to some extent invariably accompanies all continental breakup. For example, on the Newfoundland margin, a small volcanic province has been interpreted near the termination of the Charlie Gibbs Fracture Zone, whereas on the conjugate Irish margin within the Rockall Basin, magmatism appears to be more widespread and has been documented both in the north and in the south. The broader region over which volcanism has been identified on the Irish margin is suggestive of magmatic asymmetry across this conjugate margin pair and this may have direct implications for the mechanisms governing the nature of rifting and breakup. Possible causes of the magmatic asymmetry include asymmetric rifting (simple shear), post-breakup thermal anomalies in the mantle, or pre-existing compositional zones in the crust that predispose one of the margins to more melting than its conjugate. A greater understanding of the mechanisms leading to conjugate margin asymmetry will enhance our fundamental understanding of rifting processes and will also reduce hydrocarbon exploration risk by better characterizing the structural and thermal evolution of hydrocarbon bearing basins on magma-poor margins where evidence of localized magmatism exists. Here, the latest results of a conjugate margin study of the Newfoundland-Ireland pair utilizing seismic interpretation integrated with other geological and geophysical datasets are presented. Our analysis has begun to reveal the nature and timing of rift-related magmatism and the degree to which magmatic asymmetry

Marginal cost and congestion in the Italian electricity market: An indirect estimation approach

International Nuclear Information System (INIS)

Bigerna, Simona; Andrea Bollino, Carlo; Polinori, Paolo

2015-01-01

In this paper we construct an indirect measure of the supply marginal cost function for the main generators from the observed bid data in the Italian electricity market in the period 2004–2007. We compute the residual demand function for each generator, taking explicitly into account the issue of transmission line congestion. This procedure allows recovering correct zonal Lerner index and the implied measure of the marginal cost function. We find evidence of a stable U-shaped marginal cost function for three main Italian generators, but a flat function for ENEL, the former national monopolist. The policy relevance of our approach lies in the possibility to offer some empirical knowledge of the marginal cost function of each generator to the regulator to design appropriate policy measures geared to the promotion of competitive market conditions. We propose a new market surveillance mechanism, which is based on the principle of sanctioning excessive deviations from the estimated measure of the marginal cost function presented in this work. -- Highlights: •We construct an indirect measure of the supply marginal cost function. •We compute the residual demand function taking into account transmission line congestion. •We find a general evidence of a stable U-shaped marginal cost function for Italian generators. •We find flat marginal cost function for the former national monopolist. •We use excessive deviations from estimated marginal cost function as a new market surveillance mechanism

Real analytic solutions for marginal deformations in open superstring field theory

International Nuclear Information System (INIS)

Okawa, Yuji

2007-01-01

We construct analytic solutions for marginal deformations satisfying the reality condition in open superstring field theory formulated by Berkovits when operator products made of the marginal operator and the associated superconformal primary field are regular. Our strategy is based on the recent observation by Erler that the problem of finding solutions for marginal deformations in open superstring field theory can be reduced to a problem in the bosonic theory of finding a finite gauge parameter for a certain pure-gauge configuration labeled by the parameter of the marginal deformation. We find a gauge transformation generated by a real gauge parameter which infinitesimally changes the deformation parameter and construct a finite gauge parameter by its path-ordered exponential. The resulting solution satisfies the reality condition by construction

Real analytic solutions for marginal deformations in open superstring field theory

International Nuclear Information System (INIS)

Okawa, Y.

2007-04-01

We construct analytic solutions for marginal deformations satisfying the reality condition in open superstring field theory formulated by Berkovits when operator products made of the marginal operator and the associated superconformal primary field are regular. Our strategy is based on the recent observation by Erler that the problem of finding solutions for marginal deformations in open superstring field theory can be reduced to a problem in the bosonic theory of finding a finite gauge parameter for a certain pure-gauge configuration labeled by the parameter of the marginal deformation. We find a gauge transformation generated by a real gauge parameter which infinitesimally changes the deformation parameter and construct a finite gauge parameter by its path-ordered exponential. The resulting solution satisfies the reality condition by construction. (orig.)

Evaluation of thermal margin for HANARO core

Energy Technology Data Exchange (ETDEWEB)

Park, Cheol; Chae, Hee Taek; Kim Heon Il; Lim, I. C.; Lee, C. S.; Kim, H

1999-08-01

During the commissioning and the start-up of the HANARO, various design parameters were confirmed and measured. For safer operation of HANARO and resolution of the CHF penalty issue which is one of unresolved licensing problems, thermal margins for normal and transient conditions were re-evaluated reflecting the commissioning and the start-up test results and the design modifications during operation. The re-evaluation shows that the HANARO meets the design criteria for ONB margin and fuel centerline temperature under normal condition. For upset condition, it also satisfies the safety limits for CHFR and fuel centerline temperature. (Author). 11 refs., 13 tabs., 4 figs.

Modeled post-glacial landscape evolution at the southern margin of the Laurentide Ice Sheet: hydrological connection of uplands controls the pace and style of fluvial network expansion

Science.gov (United States)

Lai, J.; Anders, A. M.

2017-12-01

Landscapes of the US Midwest were repeatedly affected by the southern margin of the Laurentide Ice Sheet during the Quaternary. Glacial processes removed pre-glacial relief and left constructional landforms including low-relief till plains and high-relief moraines. As the ice retreated, meltwater was collected in subglacial or proglacial lakes and outburst floods of glacial lakes episodically carved deep valleys. These valleys provided the majority of post-glacial landscape relief. However, a significant fraction of the area of low-relief till plains was occupied by closed depressions and remained unconnected to these meltwater valleys. This area is referred to as non-contributing area (NCA) because it does not typically contribute surface runoff to stream networks. Decreasing fractions of NCA on older glacial landscape surfaces suggests that NCA becomes integrated into external drainage networks over time. We propose that this integration could occur via two different paths: 1) through capture of NCA as channel heads propagate into the upland or, 2) through erosion of a channel along a flow path that, perhaps intermittently, connects NCA to the external drainage network. We refer the two cases as "disconnected" and "connected" cases since the crucial difference between them is the hydrological connectivity on the upland. We investigate the differences in the evolution of channel networks and morphology in low relief landscapes under disconnected and connected drainage regimes through numerical simulations of fluvial and hillslope processes. We observe a substantially faster evolution of the channel network in the connected case than in the disconnected case. Modeled landscapes show that channel network in the connected case has longer, more sinuous channels. We also find that the connected case removes lower amounts of total mass than the disconnected case when the same degree of channel integration is achieved. Observed landscapes in US Midwest are more

Use of Airborne Hyperspectral Imagery to Map Soil Properties in Tilled Agricultural Fields

International Nuclear Information System (INIS)

Hively, W.D; McCarty, G.W; Reeves, J.B; Lang, M.W; Oesterling, R.A; Delwiche, S.R

2011-01-01

Soil hyperspectral reflectance imagery was obtained for six tilled (soil) agricultural fields using an airborne imaging spectrometer (400-2450 nm, -10 nm resolution, 2.5 m spatial resolution). Surface soil samples (n=315) were analyzed for carbon content, particle size distribution, and 15 agronomically important elements (Mehlich-III extraction). When partial least squares (PLS) regression of imagery-derived reflectance spectra was used to predict analyte concentrations, 13 of the 19 analytes were predicted with R 2 >0.50, including carbon (0.65), aluminum (0.76), iron (0.75), and silt content (0.79). Comparison of 15 spectral math preprocessing treatments showed that a simple first derivative worked well for nearly all analytes. The resulting PLS factors were exported as a vector of coefficients and used to calculate predicted maps of soil properties for each field. Image smoothing with a 3 x 3 low-pass filter prior to spectral data extraction improved prediction accuracy. The resulting raster maps showed variation associated with topographic factors, indicating the effect of soil redistribution and moisture regime on in-field spatial variability. High-resolution maps of soil analyte concentrations can be used to improve precision environmental management of farmlands.

Primary housing market in Elblag from 2008 till the first quarter of 2012 – selected aspects

Directory of Open Access Journals (Sweden)

Marcin Duda

2013-03-01

Full Text Available National housing market is one of the first business branches which suffered an economic slowdown due to the global economic crisis started in United States of America in 2007. In this study author presents a situation of the primary housing market in Elblag and evaluates its development prospects in upcoming years. The research hypothesis is that the external factors related to the macroeconomic issues and Elblag’s internal problems, cause constant decline in prices of new housing, similarly to other Polish cities. To confirm the presented hypothesis and the evaluation of development possibilities, the author studies housing transaction price fluctuations for the properties built and sold by developers from 2008 till the first quarter of 2012. He also analyse demographic situation of the city, mortgages market and changes in GDP and GDP per capita over the past few years.

The role of the extensive margin in export of Turkey: A comparative analysis

Directory of Open Access Journals (Sweden)

Altan Aldan

2016-06-01

Full Text Available We examine the role of extensive margin, in other words, new export products and destinations, on Turkish export performance between 1995 and 2013, in comparison with some other countries. We use two complementary methods together with several extensions taking into account critiques in the literature. Our results suggest that, Turkey was quite successful in extending its extensive margin compared to other developing countries. The growth of extensive margin mostly comes from entering into new markets. Nevertheless, the level of the extensive margin is still low as of 2013 compared to the other countries. Turkey still has important opportunities to increase its exports via extensive margin especially in products.

Assessment of Biomass Resources from Marginal Lands in APEC Economies

Energy Technology Data Exchange (ETDEWEB)

Milbrandt, A.; Overend, R. P.

2009-08-01

The goal of this study is to examine the marginal lands in Asia-Pacific Economic Cooperation (APEC) economies and evaluate their biomass productivity potential. Twelve categories of marginal lands are identified using the Global Agro-Ecological Zones system of the United Nations Food and Agriculture Organization.

Street Sex Work: Re/Constructing Discourse from Margin to Center

Science.gov (United States)

McCracken, Jill Linnette

2009-01-01

Newspaper media create interpretations of marginalized groups that require rhetorical analysis so that we can better understand these representations. This article focuses on how newspaper articles create interpretations of sex work that affect both the marginalized and mainstream communities. My ethnographic case study argues that the material…

The marginal social cost of headway for a scheduled service

DEFF Research Database (Denmark)

Fosgerau, Mogens

2009-01-01

waiting time costs as well as schedule delay costs measured relative to their desired time of arrival at the destination. They may either arrive at the station to choose just the next departure or they may plan for a specific departure in which case they incur also a planning cost. Then planning......This brief paper derives the marginal social cost of headway for a scheduled service, i.e. the cost for users of marginal increases to the time interval between departures. In brief we may call it the value of headway in analogy with the value of travel time and the value of reliability. Users have...... for a specific departure is costly but becomes more attractive at longer headways. Simple expressions for the user cost result. In particular, the marginal cost of headway is large at short headways and smaller at long headways. The difference in marginal costs is the value of time multiplied by half the headway....

Seismic Margin of 500MWe PFBR Beyond Safe Shutdown Earthquake

International Nuclear Information System (INIS)

Sajish, S.D.; Chellapandi, P.; Chetal, S.C.

2012-01-01

Summary: • Seismic design aspects of safety related systems and components of PFBR is discussed with a focus on reactor assembly components. • PFBR is situated in a low seismic area with a peak ground acceleration value of 0.156 g. • The design basis ground motion parameters for the seismic design are evaluated by deterministic method and confirmed by probabilistic seismic hazard analysis. • Review of the seismic design of various safety related systems and components indicate that margin is available to meet any demand due to an earthquake beyond SSE. • Reactor assembly vessels are the most critical components w.r.t seismic loading. • Minimum safety margin is 1.41 for plastic deformation and 1.46 against buckling. • From the preliminary investigation we come to the conclusion that PFBR can withstand an earthquake up to 0.22 g without violating any safety limits. • Additional margin can be estimated by detailed fragility analysis and seismic margin assessment methods

Validación de TILLING en evaluación de progenies endocriadas de yuca irradiada (Manihot esculenta Crantz

Directory of Open Access Journals (Sweden)

Tofiño Adriana

2009-12-01

Full Text Available

En el marco de la creciente tendencia a la agroindustrialización de la yuca, y dado que las características del almidón definen el potencial industrial de estas raíces, aquellas herramientas moleculares que permitan identificar variantes de interés deben integrarse a programas de mejoramiento genético para seleccionar eficientemente nuevos materiales parentales. En este trabajo se compararon los resultados de la técnica TILLING de genética reversa (modificada en cuanto a la visualización directa de los productos de digestión en gel de agarosa, con el método tradicional que utiliza gel de acrilamida y plataforma Li-Cor. La comparación se llevó a cabo a través de la evaluación de polimorfismo en 10 genes con control metabólico mayor de la ruta del almidón. En 150 líneas endocriadas M2, derivadas de semillas irradiadas, fueron identificadas fenotípicamente como probables mutantes y analizadas por TILLING. Solo 30% de los cebadores utilizados produjo datos de buena calidad pues la mayoría amplificó más de un blanco. Adicionalmente, la detección visual de SNP en agarosa no corresponde con los registros obtenidos a partir del genotipado por Li-Cor, pues con ella no se logró detección de SNP, ni en plantillas de mezclas de ADN, ni en muestras individuales.

Late Cenozoic flexural deformation of the middle U.S. Atlantic passive margin

Science.gov (United States)

Pazzaglia, Frank J.; Gardner, Thomas, W.

1994-01-01

Despite the century-long recognition of regional epeirogeny along the middle Atlantic passive margin, relatively few studies have focused on understanding postrift uplift mechanisms. Here, we demonstrate that epeirogenic uplift of the central Appalachian Piedmont and subsidence of the Salisbury Embayment represent first-order, flexural isostatic processes driven by continental denudation and offshore deposition. Our results show that regional epeirogenic processes, present on all Atlantic-type passive margins, are best resolved by specific stratigraphic and geomorphic relationships, rather than topography. A simple one-dimensional geodynamic model, constrained by well-dated Baltimore Canyon trough, Coastal Plain, and lower Susquehanna River (piedmont) stratigraphy, simulates flexural deforamtion of the U.S. Atlantic margin. The model represents the passive margin lithosphree as a uniformly thick elastic plate, without horizontal compressive stresses, that deforms flexurally under the stress of strike-averaged, vertically applied line loads. Model results illustrate a complex interaction among margin stratigraphy and geomorphology, the isostatic repsonse to denudational and depositional processes, and the modulating influence of exogenic forces such as eustasy. The current elevation, with respect to modern sea level, of fluvial terraces and correlateive Coastal Plain deposits or unconformities is successfully predicted through the synthesis of paleotopography, eustatic change, and margin flexure. Results suggest that the middle U.S. Atlantic margin landward of East Coast Magnetic Anomaly is underlain by lithoshpere with an average elastic thickness of 40 km (flexural rigidity, D = 4 X 10(exp 23) N m), the margin experience an average, long-term denudation rate of approximately 10m/m.y., and the Piedmont has been flexurally upwaped between 35 and 130 meters in the last 15 m.y. Long term isostatic continental uplift resulting rom denudation and basin subsidence

Long-term outcome for gastric marginal zone lymphoma treated with radiotherapy

DEFF Research Database (Denmark)

Wirth, A; Gospodarowicz, M; Aleman, B M P

2013-01-01

We evaluated the long-term results of radiotherapy for patients with gastric marginal zone lymphoma (GMZL).......We evaluated the long-term results of radiotherapy for patients with gastric marginal zone lymphoma (GMZL)....

Energy system analyses of the marginal energy technology in life cycle assessments

DEFF Research Database (Denmark)

Mathiesen, B.V.; Münster, Marie; Fruergaard, Thilde

2007-01-01

in historical and potential future energy systems. Subsequently, key LCA studies of products and different waste flows are analysed in relation to the recom- mendations in consequential LCA. Finally, a case of increased waste used for incineration is examined using an energy system analysis model......In life cycle assessments consequential LCA is used as the “state-of-the-art” methodology, which focuses on the consequences of decisions made in terms of system boundaries, allocation and selection of data, simple and dynamic marginal technology, etc.(Ekvall & Weidema 2004). In many LCA studies...... marginal technology? How is the marginal technology identified and used today? What is the consequence of not using energy system analy- sis for identifying the marginal energy technologies? The use of the methodology is examined from three angles. First, the marginal electricity technology is identified...

Confinement margins for ignition and driven operation in Iter Eda ID

International Nuclear Information System (INIS)

Johner, J.

1995-09-01

Preliminary calculations for ITER EDA ID have been performed using the 1/2D thermal equilibrium code HELIOS. It is found that: - The maximum ignition margin for ITER ID (29%) is 6% less than for ITER OD (35%) and 5% less than for ITER CDA (34%). - Decreasing the ration τ * He /τ E from the nominal value 10 to a value of 5 gives a 12% gain in the maximum ignition margin. Increasing the ration from 10 to 15 causes a 22% loss in the margin. Furthermore, ignited equilibria non longer exist for τ * He /τ E ≥ 17.6. - Operation in driven mode with 50 MW of external power increases the confinement capability by 13%. With 100 MW, the improvement is 24%. - Lowering the fusion power from 1500 to 1000 MW slightly improves the maximum ignition margin (+5%) and allows operation below the Greenwald density limit. - A 10% reduction of the toroidal magnetic field with a correlative diminution of the plasma current for constant safety factor operation, causes a dramatic reduction (-18%) of the maximum ignition margin. - A fraction of neon of 0.68% would completely suppress the ignition margin. Furthermore, ignited equilibria, with the nominal fusion power and τ * He /τ E , no longer exist when the neon fraction exceeds 0.75%. (Author). 2 refs., 10 figs

Anticipation and the adaptive control of safety margins in driving

NARCIS (Netherlands)

van der Hulst, M.; Meijman, T.F.; Rothengatter, J.A.

Driving is a task that requires the timely detection of critical events and relevant changes in traffic circumstances. Adaptation of speed and safety margins allows drivers to control the time available to react to potential hazards. One of the basic safety margins in driving is the time headway

Significance of post-resection tissue shrinkage on surgical margins of oral squamous cell carcinoma.

Science.gov (United States)

El-Fol, Hossam Abdelkader; Noman, Samer Abduljabar; Beheiri, Mohamed Galal; Khalil, Abdalla M; Kamel, Mahmoud Mohamed

2015-05-01

Resecting oral squamous cell carcinoma (SCC) with an appropriate margin of uninvolved tissue is critical in preventing local recurrence and in making decisions regarding postoperative radiation therapy. This task can be difficult due to the discrepancy between margins measured intraoperatively and those measured microscopically by the pathologist after specimen processing. A total of 61 patients underwent resective surgery with curative intent for primary oral SCC were included in this study. All patients underwent resection of the tumor with a measured 1-cm margin. Specimens were then submitted for processing and reviewing, and histopathologic margins were measured. The closest histopathologic margin was compared with the in situ margin (1 cm) to determine the percentage discrepancy. The mean discrepancy between the in situ margins and the histopathological margins of all close and positive margins were 47.6% for the buccal mucosa (with a P value corresponding to 0.05 equaling 2.1), which is statistically significant, 4.8% for the floor of mouth, 9.5% for the mandibular alveolus, 4.8% for the retromolar trigon, and 33.3% for the tongue. There is a significant difference among resection margins based on tumor anatomical location. Margins shrinkage after resection and processing should be considered at the time of the initial resection. Tumors located in the buccal mucosa show significantly greater discrepancies than tumors at other sites. These findings suggest that it is critical to consider the oral site when outlining margins to ensure adequacy of resection. Buccal SCC is an aggressive disease, and should be considered as an aggressive subsite within the oral cavity, requiring a radical and aggressive resective approach. Copyright © 2015 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Marginal adaptation of four inlay casting waxes on stone, titanium, and zirconia dies.

Science.gov (United States)

Michalakis, Konstantinos X; Kapsampeli, Vassiliki; Kitsou, Aikaterini; Kirmanidou, Yvone; Fotiou, Anna; Pissiotis, Argirios L; Calvani, Pasquale Lino; Hirayama, Hiroshi; Kudara, Yukio

2014-07-01

Different inlay casting waxes do not produce copings with satisfactory marginal accuracy when used on different die materials. The purpose of this study was to evaluate the marginal accuracy of 4 inlay casting waxes on stone dies and titanium and zirconia abutments and to correlate the findings with the degree of wetting between the die specimens and the inlay casting waxes. The inlay casting waxes tested were Starwax (Dentaurum), Unterziehwachs (Bredent), SU Esthetic wax (Schuler), and Sculpturing wax (Renfert). The marginal opening of the waxes was measured with a stereomicroscope on high-strength stone dies and on titanium and zirconia abutments. Photographic images were obtained, and the mean marginal opening for each specimen was calculated. A total of 1440 measurements were made. Wetting between die materials and waxes was determined after fabricating stone, titanium, and zirconia rectangular specimens. A calibrated pipette was used to place a drop of molten wax onto each specimen. The contact angle was calculated with software after an image of each specimen had been made with a digital camera. Collected data were subjected to a 2-way analysis of variance (α=.05). Any association between marginal accuracy and wetting of different materials was found by using the Pearson correlation. The wax factor had a statistically significant effect both on the marginal discrepancy (F=158.31, P<.001) and contact angle values (F=68.09, P<.001). A statistically significant effect of the die material factor both on the marginal adaptation (F=503.47, P<.001) and contact angle values (F=585.02, P<.001) was detected. A significant correlation between the marginal accuracy and the contact angle values (Pearson=0.881, P=.01) was also found. Stone dies provided wax copings with the best marginal integrity, followed by titanium and zirconia abutments. Unterziehwachs (Bredent), wax produced the best marginal adaptation on different die materials. A significant correlation was found

Marginal zone in femoral head avascular necrosis: scintigraphic characteristics and clinical prognostic value

International Nuclear Information System (INIS)

Milcinski, M.; Sedonja, I.; Dolinar, D.; Jevtic, V.

2002-01-01

Aim: Marginal zone, seen on magnetic resonance imaging (MRI) in femoral head avascular necrosis, consists of granulation tissue and sclerosis at the junction of necrotic and normal bone. Prognostic value of this finding is not clear. Aim of our study was to evaluate osteoblastic activity of marginal zone with bone scintigraphy and to assess prognostic importance of marginal zone for further evolution of femoral head necrosis. Material and methods: MRI was performed in 37 hips in 26 patients (17 m, 9 f, 20-64 y, mean 42,9 y) with Ficat 0-II avascular necrosis (SE T1W, STIR and SE T1W FAT.SAT after Gd DTPA in the coronal plane and GE FLASH in the sagittal plane). In 26 hips of 17 patients planar and pinhole scintigraphy with 99mTc-DPD was performed. Results: On MRI, marginal zone divided necrotic and normal bone in 26/37 (70,3%) hips, in 14/26 it was thin (2% of femoral head diameter or less), but in 12/26 it was wide (more than 2% of femoral head diameter). In 11/37 (29,7%) hips marginal zone was not seen. Pinhole scintigraphy was performed in 26 hips; in all 10/10 (100%) hips with wide marginal zone, seen on MRI, increased osteoblastic activity was detected, while only in 1/9 (11,1%) hips with thin marginal zone on MRI osteoblastic activity was increased. Patients were followed 1 to 5 years (mean 2,2 y). In hips without marginal zone no collapse of femoral head was seen until now, in 2/11 (18,2%) femoral heads MRI and clinical regression was observed. Ten of 12 lesions with wide marginal zone (83,3 %) collapsed 0,25 to 2,5 (mean 1) years after onset of pain. Two of 12 lesions with wide marginal zone (16,7%) have not collapsed until now. From lesions with thin marginal zone, 4/14 (28,6 %) collapsed 0,7 to 3 (mean 1,9) years after onset of pain, 10/14 (71,4%) did not collapse until now. Conclusion: Increased osteoblastic activity in wide marginal zone between necrotic and vital bone in hip avascular necrosis is bad prognostic factor for femoral head collapse

In vitro evaluation of the marginal fit of different all-ceramic crowns

Directory of Open Access Journals (Sweden)

Munir Tolga Yucel

2013-09-01

Conclusion: In-Ceram all-ceramic crowns showed the largest marginal gap, and Celay crowns showed the smallest marginal gap in both die groups. The marginal discrepancies found in this study were all within the clinically acceptable standard of 120 μm.

Surgical Margins and the Risk of Local-Regional Recurrence After Mastectomy Without Radiation Therapy

International Nuclear Information System (INIS)

Childs, Stephanie K.; Chen Yuhui; Duggan, Margaret M.; Golshan, Mehra; Pochebit, Stephen; Wong, Julia S.; Bellon, Jennifer R.

2012-01-01

Purpose: Although positive surgical margins are generally associated with a higher risk of local-regional recurrence (LRR) for most solid tumors, their significance after mastectomy remains unclear. We sought to clarify the influence of the mastectomy margin on the risk of LRR. Methods and Materials: The retrospective cohort consisted of 397 women who underwent mastectomy and no radiation for newly diagnosed invasive breast cancer from 1998-2005. Time to isolated LRR and time to distant metastasis (DM) were evaluated by use of cumulative-incidence analysis and competing-risks regression analysis. DM was considered a competing event for analysis of isolated LRR. Results: The median follow-up was 6.7 years (range, 0.5-12.8 years). The superficial margin was positive in 41 patients (10%) and close (≤2 mm) in 56 (14%). The deep margin was positive in 23 patients (6%) and close in 34 (9%). The 5-year LRR and DM rates for all patients were 2.4% (95% confidence interval, 0.9-4.0) and 3.5% (95% confidence interval, 1.6-5.3) respectively. Fourteen patients had an LRR. Margin status was significantly associated with time to isolated LRR (P=.04); patients with positive margins had a 5-year LRR of 6.2%, whereas patients with close margins and negative margins had 5-year LRRs of 1.5% and 1.9%, respectively. On univariate analysis, positive margins, positive nodes, lymphovascular invasion, grade 3 histology, and triple-negative subtype were associated with significantly higher rates of LRR. When these factors were included in a multivariate analysis, only positive margins and triple-negative subtype were associated with the risk of LRR. Conclusions: Patients with positive mastectomy margins had a significantly higher rate of LRR than those with a close or negative margin. However, the absolute risk of LRR in patients with a positive surgical margin in this series was low, and therefore the benefit of postmastectomy radiation in this population with otherwise favorable features

A comparison of the marginal fit of In-Ceram, IPS Empress, and Procera crowns.

Science.gov (United States)

Sulaiman, F; Chai, J; Jameson, L M; Wozniak, W T

1997-01-01

The in vitro marginal fit of three all-ceramic crown systems (In-Ceram, Procera, and IPS Empress) was compared. All crown systems were significantly different from each other at P = 0.05. In-Ceram exhibited the greatest marginal discrepancy (161 microns), followed by Procera (83 microns), and IPS Empress (63 microns). There were no significant differences among the various stages of the crown fabrication: core fabrication, porcelain veneering, and glazing. The facial and lingual margins exhibited significantly larger marginal discrepancies than the mesial and distal margins.

Characterization of DNAPL Source Zone Arcgitecture in Clay Till and Limestone Bedrock by Integrated Site Investigations with Innovative and Current Techniques

DEFF Research Database (Denmark)

Broholm, Mette Martina; Janniche, Gry Sander; Fjordbøge, Annika Sidelmann

facility for perchloroethene (PCE) and trichloroethene (TCE) at the Naverland site near Copenhagen, Denmark, has resulted in PCE and TCE DNAPL impacts to a fractured clay till and an underlying fractured limestone aquifer/bedrock. A range of innovative and current site investigative tools for direct...... with discrete subsampling for quantitative analysis, SudanIV hydrophobic colour test, colour spray test, PID and geologic descriptions; NAPL and FACT FLUTe exposure and discrete FACT subsampling and analysis; liquid sampling from boreholes; and a radon and PCE/TCE soil gas survey. Investigations...

Talking (and Not Talking) about Race, Social Class and Dis/Ability: Working Margin to Margin

Science.gov (United States)

Ferri, Beth A.; Connor, David J.

2014-01-01

In this article we examine some of the omnipresent yet unacknowledged discourses of social and economic disadvantage and dis/ability within schools in the US. First, we document ways that social class, race, and dis/ability function within schools to further disadvantage and exclude already marginalized students. Next, we show how particular ways…

A Semiparametric Marginalized Model for Longitudinal Data with Informative Dropout

Directory of Open Access Journals (Sweden)

Mengling Liu

2012-01-01

Full Text Available We propose a marginalized joint-modeling approach for marginal inference on the association between longitudinal responses and covariates when longitudinal measurements are subject to informative dropouts. The proposed model is motivated by the idea of linking longitudinal responses and dropout times by latent variables while focusing on marginal inferences. We develop a simple inference procedure based on a series of estimating equations, and the resulting estimators are consistent and asymptotically normal with a sandwich-type covariance matrix ready to be estimated by the usual plug-in rule. The performance of our approach is evaluated through simulations and illustrated with a renal disease data application.

Advancing Understanding of Earthquakes by Drilling an Eroding Convergent Margin

Science.gov (United States)

von Huene, R.; Vannucchi, P.; Ranero, C. R.

2010-12-01

A program of IODP with great societal relevance is sampling and instrumenting the seismogenic zone. The zone generates great earthquakes that trigger tsunamis, and submarine slides thereby endangering coastal communities containing over sixty percent of the earth’s population. To asses and mitigate this endangerment it is urgent to advance understanding of fault dynamics that allows more timely anticipation of hazardous seismicity. Seismogenesis on accreting and eroding convergent plate boundaries apparently differ because of dissimilar materials along the interplate fault. As the history of instrumentally recorded earthquakes expands the difference becomes clearer. The more homogeneous clay, silt and sand subducted at accreting margins is associated with great earthquakes (M 9) whereas the fragmented upper plate rock that can dominate subducted material along an eroding margin plate interface is associated with many tsunamigenic earthquakes (Bilek, 2010). Few areas have been identified where the seismogenic zone can be reached with scientific drilling. In IODP accreting margins are studied on the NanTroSeize drill transect off Japan where the ultimate drilling of the seismogenic interface may occur by the end of IODP. The eroding Costa Rica margin will be studied in CRISP where a drill program will begin in 2011. The Costa Rican geophysical site survey will be complete with acquisition and processing of 3D seismic data in 2011 but the entire drilling will not be accomplished in IODP. It is appropriate that the accreting margin study be accomplished soon considering the indications of a pending great earthquake that will affect a country that has devoted enormous resources to IODP. However, understanding the erosional end-member is scientifically as important to an understanding of fault mechanics. Transoceanic tsunamis affect the entire Pacific rim where most subduction zones are eroding margins. The Costa Rican subduction zone is less complex operationally and

The Role of Field Margins in Agro-biodiversity Management at the Farm Level

Directory of Open Access Journals (Sweden)

Giulio Lazzerini

2007-06-01

Full Text Available The agroecosystem could be considered as a mosaic so large to involve fields with annual and perennial crops, pastures, spots of wildwood, semi-natural habitats, vegetation in the edges of fields. In the agroecosystem these ecological infrastructures have a positive effects on the crops because of the exchange among community of organisms, materials and energy. The aim of this research is to evaluate the effects of field margins on some biodiversity components (plant species and carabid beetles of four farms located in Val d’Orcia (Tuscany. We compared three types of field margins: 1. Cultivated margin strips; 2. Sown grass margin strips; 3. Wild margin strips with hedgerow. In a very simplified typology of farming system, like the one studied (Val d’Orcia, the presence of field margins (hedges, margin strips and semi-natural habitats associated with the boundary is very important for its ecological effects: it improves the planned biodiversity, gives habitat, refuge, food and corridors for the movement to the different species of organisms in the area. Applying the multivariate analysis to the experimental data, we can notice a positive effect of the presence of field margins on the trend of both components of biodiversity. This positive effect, which support the mechanisms of autoregulation of the agroecosystems, is very important especially for organic and biodynamic agriculture, where the use of pesticides is not allowed.

Research on the margin of futures markets and the policy spillover effect

Institute of Scientific and Technical Information of China (English)

Difang Wan; Yang Yang; Dong Fang; Guang Yang

2011-01-01

Purpose-The purpose of this paper is to investigate whether the change of margin in Chinese futures markets has policy spillover effects.Design/methodology/approach-The paper constructs a model based on Harzmark and on Chng,taking Chinese futures markets status quo as a single species and restrictions on foreign investment into consideration,introduces the assumptions of spillover effect of speculators,then obtains investor's demand function.Subsequently,the effects of Shanghai Futures Exchange's 11 instances of margin changing are analyzed.Findings-The paper finds that in the Chinese futures market,margin changing has impact on the open interest (OI) and the speculator spillover effect is validated.Research limitations/implications-The irrational behavior of investors in markets is not taken into account in the model and data about spillover speculators were not directly available.Originality/value-The paper usefully analyzes the effects of the Shanghai Futures Exchange's 11 instances of margin changing from 2000 to 2007 and examines the actual effects of margin-changing policy,in the views of OI,trading volume and the externality,the results showing that margin changing has impact on investor structure and validates the existence of the assumed speculator spillover effect.

PENDIDIKAN ALTERNATIF UNTUK PEREMPUAN MARGINAL DI PEDESAAN

Directory of Open Access Journals (Sweden)

Ratnawati Tahir

2011-11-01

Full Text Available Abstract: Alternative Education for Marginalized Women in Rural Areas. The study aims to find alter­native forms of education for marginalized women, the process of forming study groups and gender based learning process that serves the center of the development of education, leadership and a source of economic empowerment. The study uses qualitative methods, involving a group of women who have attended an al­ternative education. Researchers and informants from community leaders. The results showed that the form of alternative education is a method of adult education or andragogy. Study groups consisted of basic literacy and functional literacy. The learning process begins with the sharing of learning, reflection on life experience and role play method. The result is 65% of participants have increased the ability of reading, writing and numeracy, and understanding of the issues of women who have confidence in the decision making of households and communities. Abstrak: Pendidikan Alternatif untuk Perempuan Marginal di Pedesaan. Penelitian ini bertujuan mengetahui bentuk pendidikan alternatif untuk perempuan marginal, proses pembentukan kelompok belajar, dan proses pembelajaran berperspektif gender yang berfungsi menjadi pusat pengembangan pendidikan, kepemimpinan, dan sumber penguatan ekonomi. Penelitian menggunakan metode kualitatif, mengambil satu kelompok perempuan yang telah mengikuti pendidikan alternatif. Informan terdiri atas tokoh masyarakat, seperti Kepala Desa, Ketua RT/RW, dan ibu rumah tangga. Hasil penelitian menunjukkan bahwa bentuk pembelajaran pendidikan alternatif adalah metode pendidikan orang dewasa atau andragogy. Pembentukan kelompok belajar terdiri atas; kelompok baca tulis dan keaksaraan fungsional. Proses pembe­lajaran dimulai dengan sharing pembelajaran, refleksi pengalaman hidup, dan metode role play. Hasilnya 65% peserta pembelajaran mengalami peningkatan kemampuan membaca, menulis, dan berhitung, serta pema

Stability of marginally outer trapped surfaces and symmetries

Energy Technology Data Exchange (ETDEWEB)

Carrasco, Alberto; Mars, Marc, E-mail: acf@usal.e, E-mail: marc@usal.e [Facultad de Ciencias, Universidad de Salamanca, Plaza de la Merced s/n, 37008 Salamanca (Spain)

2009-09-07

We study the properties of stable, strictly stable and locally outermost marginally outer trapped surfaces in spacelike hypersurfaces of spacetimes possessing certain symmetries such as isometries, homotheties and conformal Killings. We first obtain results for general diffeomorphisms in terms of the so-called metric deformation tensor and then particularize to different types of symmetries. In particular, we find restrictions at the surfaces on the vector field generating the symmetry. Some consequences are discussed. As an application, we present a result on non-existence of stable marginally outer trapped surfaces in slices of FLRW.

Manipulating field margins to increase predation intensity in fields of winter wheat (Triticum eastivum)

DEFF Research Database (Denmark)

Mansion-Vaquie, Agathe; Ferrante, Marco; Cook, S M

2017-01-01

, intraguild predation, hyperparasitism) may complicate the assumption that a higher density of natural enemies would increase the level of biological control. We investigated the natural enemy guild composition and the predation rate along flower vs. grass margins at the edge of winter wheat (Triticum...... to the two margin types: specialists (mostly parasitic wasps) were attracted by the flower margins, while generalists (ground beetles, rove beetles and spiders) were more active in grass margins. The number of artificial caterpillars attacked was significantly greater in grass margins (mean = 48.9%, SD = 24...

Passive target tracking using marginalized particle filter

Institute of Scientific and Technical Information of China (English)

无

2007-01-01

A marginalized particle filtering(MPF)approach is proposed for target tracking under the background of passive measurement.Essentially,the MPF is a combination of particle filtering technique and Kalman filter.By making full use of marginalization,the distributions of the tractable linear part of the total state variables are updated analytically using Kalman filter,and only the lower-dimensional nonlinear state variable needs to be dealt with using particle filter.Simulation studies are performed on an illustrative example,and the results show that the MPF method leads to a significant reduction of the tracking errors when compared with the direct particle implementation.Real data test results also validate the effectiveness of the presented method.

Analytic solutions for marginal deformations in open superstring field theory

International Nuclear Information System (INIS)

Okawa, Y.

2007-04-01

We extend the calculable analytic approach to marginal deformations recently developed in open bosonic string field theory to open superstring field theory formulated by Berkovits. We construct analytic solutions to all orders in the deformation parameter when operator products made of the marginal operator and the associated superconformal primary field are regular. (orig.)

Marginalized Youth. An Introduction.

OpenAIRE

Kessl, Fabian; Otto, Hans-Uwe

2009-01-01

The life conduct of marginalized groups has become subject to increasing levels of risk in advanced capitalist societies. In particular, children and young people are confronted with the harsh consequences of a “new poverty” in the contemporary era. The demographic complexion of today’s poverty is youthful, as a number of government reports have once again documented in recent years in Australia, Germany, France, Great Britain, the US or Scandinavian countries. Key youth studies have shown a ...

Occurrence of Agricultural Chemicals in Shallow Ground Water and the Unsaturated Zone, Northeast Nebraska Glacial Till, 2002-04

Science.gov (United States)

Stanton, Jennifer S.; Steele, Gregory V.; Vogel, Jason R.

2007-01-01

Agricultural chemicals applied at the land surface in northeast Nebraska can move downward, past the crop root zone, to ground water. Because agricultural chemicals applied at the land surface are more likely to be observed in the shallowest part of an aquifer, an assessment of shallow ground-water and unsaturated zone quality in the northeast Nebraska glacial till was completed between 2002 and 2004. Ground-water samples were collected at the first occurrence of ground water or just below the water table at 32 sites located in areas likely affected by agriculture. Four of the 32 sites were situated along a ground-water flow path with its downgradient end next to Maple Creek. Twenty-eight sites were installed immediately adjacent to agricultural fields throughout the glacial-till area. In addition to those 32 sites, two sites were installed in pastures to represent ground-water conditions in a non-cropland setting. Ground-water samples were analyzed for physical properties and concentrations of nitrogen and phosphorus compounds, selected pesticides and pesticide degradates, dissolved solids, major ions, trace elements, and dissolved organic carbon. Chlorofluorocarbons (CFCs) or sulfur hexafluoride (SF6) concentrations were analyzed at about 70 percent of the monitoring wells to estimate the residence time of ground water. Borehole-core samples were collected from 28 of the well boreholes. Sediment in the unsaturated zone was analyzed for nitrate, chloride, and ammonia concentrations. Analytical results indicated that the agricultural chemicals most often detected during this study were nitrates and herbicides. Nitrate as nitrogen (nitrate-N) concentrations (2003 median 9.53 milligrams per liter) indicated that human activity has affected the water quality of recently recharged ground water in approximately two-thirds of the wells near corn and soybean fields. The principal pesticide compounds that were detected reflect the most-used pesticides in the area and

Regional Marginal Abatement Cost Curves for NOx

Data.gov (United States)

U.S. Environmental Protection Agency — Data underlying the figures included in the manuscript "Marginal abatement cost curve for NOx incorporating controls, renewable electricity, energy efficiency and...

Variability of the geothermal gradient across two differently aged magma-rich continental rifted margins of the Atlantic Ocean: the Southwest African and the Norwegian margins

Science.gov (United States)

Gholamrezaie, Ershad; Scheck-Wenderoth, Magdalena; Sippel, Judith; Strecker, Manfred R.

2018-02-01

The aim of this study is to investigate the shallow thermal field differences for two differently aged passive continental margins by analyzing regional variations in geothermal gradient and exploring the controlling factors for these variations. Hence, we analyzed two previously published 3-D conductive and lithospheric-scale thermal models of the Southwest African and the Norwegian passive margins. These 3-D models differentiate various sedimentary, crustal, and mantle units and integrate different geophysical data such as seismic observations and the gravity field. We extracted the temperature-depth distributions in 1 km intervals down to 6 km below the upper thermal boundary condition. The geothermal gradient was then calculated for these intervals between the upper thermal boundary condition and the respective depth levels (1, 2, 3, 4, 5, and 6 km below the upper thermal boundary condition). According to our results, the geothermal gradient decreases with increasing depth and shows varying lateral trends and values for these two different margins. We compare the 3-D geological structural models and the geothermal gradient variations for both thermal models and show how radiogenic heat production, sediment insulating effect, and thermal lithosphere-asthenosphere boundary (LAB) depth influence the shallow thermal field pattern. The results indicate an ongoing process of oceanic mantle cooling at the young Norwegian margin compared with the old SW African passive margin that seems to be thermally equilibrated in the present day.

A method of accurate determination of voltage stability margin

Energy Technology Data Exchange (ETDEWEB)

Wiszniewski, A.; Rebizant, W. [Wroclaw Univ. of Technology, Wroclaw (Poland); Klimek, A. [AREVA Transmission and Distribution, Stafford (United Kingdom)

2008-07-01

In the process of developing power system disturbance, voltage instability at the receiving substations often contributes to deteriorating system stability, which eventually may lead to severe blackouts. The voltage stability margin at receiving substations may be used to determine measures to prevent voltage collapse, primarily by operating or blocking the transformer tap changing device, or by load shedding. The best measure of the stability margin is the actual load to source impedance ratio and its critical value, which is unity. This paper presented an accurate method of calculating the load to source impedance ratio, derived from the Thevenin's equivalent circuit of the system, which led to calculation of the stability margin. The paper described the calculation of the load to source impedance ratio including the supporting equations. The calculation was based on the very definition of voltage stability, which says that system stability is maintained as long as the change of power, which follows the increase of admittance is positive. The testing of the stability margin assessment method was performed in a simulative way for a number of power network structures and simulation scenarios. Results of the simulations revealed that this method is accurate and stable for all possible events occurring downstream of the device location. 3 refs., 8 figs.

Marginal Consistency: Upper-Bounding Partition Functions over Commutative Semirings.

Science.gov (United States)

Werner, Tomás

2015-07-01

Many inference tasks in pattern recognition and artificial intelligence lead to partition functions in which addition and multiplication are abstract binary operations forming a commutative semiring. By generalizing max-sum diffusion (one of convergent message passing algorithms for approximate MAP inference in graphical models), we propose an iterative algorithm to upper bound such partition functions over commutative semirings. The iteration of the algorithm is remarkably simple: change any two factors of the partition function such that their product remains the same and their overlapping marginals become equal. In many commutative semirings, repeating this iteration for different pairs of factors converges to a fixed point when the overlapping marginals of every pair of factors coincide. We call this state marginal consistency. During that, an upper bound on the partition function monotonically decreases. This abstract algorithm unifies several existing algorithms, including max-sum diffusion and basic constraint propagation (or local consistency) algorithms in constraint programming. We further construct a hierarchy of marginal consistencies of increasingly higher levels and show than any such level can be enforced by adding identity factors of higher arity (order). Finally, we discuss instances of the framework for several semirings, including the distributive lattice and the max-sum and sum-product semirings.

Constraints Imposed by Rift Inheritance on the Compressional Reactivation of a Hyperextended Margin: Mapping Rift Domains in the North Iberian Margin and in the Cantabrian Mountains

Science.gov (United States)

Cadenas, P.; Fernández-Viejo, G.; Pulgar, J. A.; Tugend, J.; Manatschal, G.; Minshull, T. A.

2018-03-01

The Alpine Pyrenean-Cantabrian orogen developed along the plate boundary between Iberia and Europe, involving the inversion of Mesozoic hyperextended basins along the southern Biscay margin. Thus, this margin represents a natural laboratory to analyze the control of structural rift inheritance on the compressional reactivation of a continental margin. With the aim to identify former rift domains and investigate their role during the subsequent compression, we performed a structural analysis of the central and western North Iberian margin, based on the interpretation of seismic reflection profiles and local constraints from drill-hole data. Seismic interpretations and published seismic velocity models enabled the development of crustal thickness maps that helped to constrain further the offshore and onshore segmentation. Based on all these constraints, we present a rift domain map across the central and western North Iberian margin, as far as the adjacent western Cantabrian Mountains. Furthermore, we provide a first-order description of the margin segmentation resulting from its polyphase tectonic evolution. The most striking result is the presence of a hyperthinned domain (e.g., Asturian Basin) along the central continental platform that is bounded to the north by the Le Danois High, interpreted as a rift-related continental block separating two distinctive hyperextended domains. From the analysis of the rift domain map and the distribution of reactivation structures, we conclude that the landward limit of the necking domain and the hyperextended domains, respectively, guide and localize the compressional overprint. The Le Danois block acted as a local buttress, conditioning the inversion of the Asturian Basin.

Circumferential scouting punch biopsies to delineate surgical margin for dermatofibrosarcoma protuberans

Directory of Open Access Journals (Sweden)

Tsung-Mao Huang

2012-03-01

Full Text Available Dermatofibrosarcoma protuberans (DFSP is an uncommon soft-tissue tumor involving the dermis and subcutaneous tissue with a high local recurrence rate after standard excision. Mohs micrographic surgery offers a lower recurrence rate. However, the procedure requires multiple stages of excision with intraoperative histopathological mapping, which is time consuming and expensive. We report our experience of using circumferential scouting punch biopsy technique in five patients to determine in advance the resection margins for DFSP prior to wide excision. Multiple 4 mm punches, usually eight in number, were performed 1–2.5 cm around the palpable borders of DFSP to delineate the resection margins in five consecutive patients. Tumors were excised at a later date along the margin defined by these biopsies and the wounds were repaired with skin graft. The operation was completed in 2 hours in all cases excluding one that required frozen sections for deep margin. No recurrence was noted 2–10 years after the operations. The results suggest that circumferential scouting punch biopsies before wide excision may be an alternative method to define the resection margins for DFSP when Mohs surgery is not available.

Wintertime pytoplankton bloom in the Subarctic Pacific supportedby continental margin iron

Energy Technology Data Exchange (ETDEWEB)

Lam, Phoebe J.; Bishop, James K.B.; Henning, Cara C.; Marcus,Matthew A.; Waychunas, Glenn A.; Fung, Inez

2004-06-08

Heightened biological activity was observed in February 1996in the high-nutrient low-chlorophyll (HNLC) subarctic North PacificOcean, a region that is thought to beiron-limited. Here we provideevidence supporting the hypothesis that Ocean Station Papa (OSP) in thesubarctic Pacific received a lateral supply of particulate iron from thecontinental margin off the Aleutian Islands in the winter, coincidentwith the observed biological bloom. Synchrotron X-ray analysis was usedto describe the physical form, chemistry, and depth distributions of ironin size fractionated particulate matter samples. The analysis revealsthat discrete micron-sized iron-rich hotspots are ubiquitous in the upper200m at OSP, more than 900km from the closest coast. The specifics of thechemistry and depth profiles of the Fe hot spots trace them to thecontinental margins. We thus hypothesize that iron hotspots are a markerfor the delivery of iron from the continental margin. We confirm thedelivery of continental margin iron to the open ocean using an oceangeneral circulation model with an iron-like tracer source at thecontinental margin. We suggest that iron from the continental marginstimulated a wintertime phytoplankton bloom, partially relieving the HNLCcondition.

Model-Based Systems Engineering Approach to Managing Mass Margin

Science.gov (United States)

Chung, Seung H.; Bayer, Todd J.; Cole, Bjorn; Cooke, Brian; Dekens, Frank; Delp, Christopher; Lam, Doris

2012-01-01

When designing a flight system from concept through implementation, one of the fundamental systems engineering tasks ismanaging the mass margin and a mass equipment list (MEL) of the flight system. While generating a MEL and computing a mass margin is conceptually a trivial task, maintaining consistent and correct MELs and mass margins can be challenging due to the current practices of maintaining duplicate information in various forms, such as diagrams and tables, and in various media, such as files and emails. We have overcome this challenge through a model-based systems engineering (MBSE) approach within which we allow only a single-source-of-truth. In this paper we describe the modeling patternsused to capture the single-source-of-truth and the views that have been developed for the Europa Habitability Mission (EHM) project, a mission concept study, at the Jet Propulsion Laboratory (JPL).

Pathologic margin involvement and the risk of recurrence in patients treated with breast-conserving therapy

International Nuclear Information System (INIS)

Gage, Irene; Nixon, Asa J.; Schnitt, Stuart J.; Recht, Abram; Gelman, Rebecca; Silver, Barbara; Connolly, James L.; Harris, Jay R.

1995-01-01

PURPOSE: To assess the relationship between microscopic margin status and recurrence after breast-conserving therapy for tumors with or without an extensive intraductal component (EIC). MATERIALS AND METHODS: During the years 1968 to 1986, 1865 women with unilateral clinical stage I or II breast cancer were treated with radiation therapy for breast conservation. Of these, 340 received ≥60 Gy to the tumor bed and had margins that were evaluable on review of their pathologic slides; these constitute the study population. The median follow-up was 109 months. All available slides were reviewed by one of the study pathologists (SS, JC). Final radial margins of excision were classified as negative >1 mm (no invasive or ductal carcinoma in-situ within 1 mm of the inked margin), negative ≤1 mm (any carcinoma ≤1 mm of the inked margin but not at ink) or positive (any carcinoma at the inked margin). A focally positive margin was defined as any invasive or in-situ carcinoma at the margin in ≤3 LPF. The extent of positivity was not evaluable in 2 patients and the distance of the tumor from the margin was not evaluable in 48 patients with a negative margin. Thirty-nine percent of EIC-negative and 46% of EIC-positive patients underwent a re-excision and, for these, the final margin analyzed was from the re-excised specimen. The median dose to the tumor bed was 63 Gy for patients with positive margins and 62 Gy for patients with negative margins. Recurrent disease was classified as ipsilateral breast recurrence (IBR) or distant metastasis/regional nodal failure (DM/RNF). RESULTS: Five year crude rates for the first site of recurrence were calculated for 340 patients evaluable at 5 years. Results were tabulated separately for all patients, EIC-negative and EIC-positive. All p-values tested for differences in the distribution of sites of first failure. CONCLUSIONS: The risk of ipsilateral breast recurrence is equally low for patients with close (≤1 mm) or negative (>1 mm

Evaluation of seismic margins for an in-plant piping system

International Nuclear Information System (INIS)

Kot, C.A.; Srinivasan, M.G.; Hsieh, B.J.

1991-01-01

Earthquake experience as well as experiments indicate that, in general, piping systems are quite rugged in resisting seismic loadings. Therefore there is a basis to hold that the seismic margin against pipe failure is very high for systems designed according to current practice. However, there is very little data, either from tests or from earthquake experience, on the actual margin or excess capacity (against failure from seismic loading) of in-plant piping systems. Design of nuclear power plant piping systems in the US is governed by the criteria given in the ASME Boiler and Pressure Vessel (B ampersand PV) Code, which assure that pipe stresses are within specified allowable limits. Generally linear elastic analytical methods are used to determine the stresses in the pipe and forces in pipe supports. The objective of this study is to verify that piping designed according to current practice does indeed have a large margin against failure and to quantify the excess capacity for piping and dynamic pipe supports on the basis of data obtained in a series of high-level seismic experiments (designated SHAM) on an in-plant piping system at the HDR (Heissdampfreaktor) Test Facility in Germany. Note that in the present context, seismic margin refers to the deterministic excess capacities of piping or supports compared to their design capacities. The excess seismic capacities or margins of a prototypical in-plant piping system and its components are evaluated by comparing measured inputs and responses from high-level simulated seismic experiments with design loads and allowables. Large excess capacities are clearly demonstrated against pipe and overall system failure with the lower bound being about four. For snubbers the lower bound margin is estimated at two and for rigid strut supports at five. 4 refs., 2 figs., 2 tabs

Estimating Marginal Returns to Education. NBER Working Paper No. 16474

Science.gov (United States)

Carneiro, Pedro; Heckman, James J.; Vytlacil, Edward J.

2010-01-01

This paper estimates the marginal returns to college for individuals induced to enroll in college by different marginal policy changes. The recent instrumental variables literature seeks to estimate this parameter, but in general it does so only under strong assumptions that are tested and found wanting. We show how to utilize economic theory and…

Correlation between margin fit and microleakage in complete crowns cemented with three luting agents

Directory of Open Access Journals (Sweden)

Paulo Henrique Orlato Rossetti

2008-02-01

Full Text Available Microleakage can be related to margin misfit. Also, traditional microleakage techniques are time-consuming. This study evaluated the existence of correlation between in vitro margin fit and a new microleakage technique for complete crowns cemented with 3 different luting agents. Thirty human premolars were prepared for full-coverage crowns with a convergence angle of 6 degrees, chamfer margin of 1.2 mm circumferentially, and occlusal reduction of 1.5 mm. Ni-Cr cast crowns were cemented with either zinc phosphate (ZP (S.S. White, resin-modified glass-ionomer (RMGI (Rely X Luting Cement or a resin-based luting agent (RC (Enforce. Margin fit (seating discrepancy and margin gap was evaluated according to criteria in the literature under microscope with 0.001 mm accuracy. After thermal cycling, crowns were longitudinally sectioned and microleakage scores at tooth-cement interface were obtained and recorded at ×100 magnification. Margin fit parameters were compared with the one-way ANOVA test and microleakage scores with Kruskal-Wallis and Dunn's tests (alpha=0.05. Correlation between margin fit and microleakage was analyzed with the Spearman's test (alpha=0.05. Seating discrepancy and marginal gap values ranged from 81.82 µm to 137.22 µm (p=0.117, and from 75.42 µm to 78.49 µm (p=0.940, respectively. Marginal microleakage scores were ZP=3.02, RMGI=0.35 and RC=0.12 (p0.05. Conclusion: Margin fit parameters and microleakage showed no strong correlations; cast crowns cemented with RMGI and RC had lower microleakage scores than ZP cement.

Glacitectonic deformation around the retreating margin of the last Irish ice sheet

Science.gov (United States)

Knight, J.

2008-12-01

Evidence for ice-marginal glacitectonic shunting and deformation of bedrock slabs is described from three sites around the west coast of Ireland. These sites (Brandon Bay, County Kerry; Pigeon Point, County Mayo; Inishcrone, County Sligo) are all locations where the late Devensian ice margin retreated on land and was confined to within limestone bedrock embayments. At these sites, flat-lying bedrock slabs (bedrock slabs have been variously stacked, rotated, deformed into open folds, and brecciated. Separating the bedrock slabs is either a thin layer (bedrock that shows internal folding; or a thicker (bedrock fractures and bedding planes and away from the ice margin, and that bedrock slabs were moved in part by hydraulic lift as well as thrust-style ice-marginal tectonics. The presence of a mosaic of warm and frozen ice-bed patches, in combination with strong geologic control and meltwater generation from behind the ice margin, can help explain formation of these unusual bedrock slab features.

New examples of marginally trapped surfaces and tubes in warped spacetimes

International Nuclear Information System (INIS)

Flores, J L; Haesen, S; Ortega, M

2010-01-01

In this paper we provide new examples of marginally trapped surfaces and tubes in FLRW spacetimes by using a basic relation between these objects and CMC surfaces in 3-manifolds. We also provide a new method to construct marginally trapped surfaces in closed FLRW spacetimes, which is based on the classical Hopf map. The utility of this method is illustrated by providing marginally trapped surfaces crossing the expanding and collapsing regions of a closed FLRW spacetime. The approach introduced in this paper is also extended to twisted spaces.

Denying Foreign Bank Entry: Implications For Bank Interest Margins

OpenAIRE

Ross Levine

2003-01-01

This paper examines the impact of restricting foreign bank entry on bank net interest margins while controlling for (a) impediments to domestic bank entry, (b) the degree of foreign bank ownership of the domestic banking industry, (c) an array of bank-specific characteristics, (c) banking sectorconcentration, and (d) various country traits. Using data on almost 1200 banks across 47 countries, the results suggest that restricting foreign bank entry boosts bank net interest margins. Also, restr...

Splenic marginal zone lymphoma: comprehensive analysis of gene expression and miRNA profiling.

Science.gov (United States)

Arribas, Alberto J; Gómez-Abad, Cristina; Sánchez-Beato, Margarita; Martinez, Nerea; Dilisio, Lorena; Casado, Felipe; Cruz, Miguel A; Algara, Patrocinio; Piris, Miguel A; Mollejo, Manuela

2013-07-01

Splenic marginal zone lymphoma is a small B-cell neoplasm whose molecular pathogenesis is still essentially unknown and whose differentiation from other small B-cell lymphomas is hampered by the lack of specific markers. We have analyzed the gene expression and miRNA profiles of 31 splenic marginal zone lymphoma cases. For comparison, 7 spleens with reactive lymphoid hyperplasia, 10 spleens infiltrated by chronic lymphocytic leukemia, 12 spleens with follicular lymphoma, 6 spleens infiltrated by mantle cell lymphoma and 15 lymph nodes infiltrated by nodal marginal zone lymphoma were included. The results were validated by qRT-PCR in an independent series including 77 paraffin-embedded splenic marginal zone lymphomas. The splenic marginal zone lymphoma miRNA signature had deregulated expression of 51 miRNAs. The most highly overexpressed miRNAs were miR-155, miR-21, miR-34a, miR-193b and miR-100, while the most repressed miRNAs were miR-377, miR-27b, miR-145, miR-376a and miR-424. MiRNAs located in 14q32-31 were underexpressed in splenic marginal zone lymphoma compared with reactive lymphoid tissues and other B-cell lymphomas. Finally, the gene expression data were integrated with the miRNA profile to identify functional relationships between genes and deregulated miRNAs. Our study reveals miRNAs that are deregulated in splenic marginal zone lymphoma and identifies new candidate diagnostic molecules for splenic marginal zone lymphoma.