Experiência global no fechamento percutâneo do canal arterial Overall experience with percutaneous occlusion of the patent ductus arteriosus

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Carlos Augusto Cardoso Pedra

1998-12-01

Full Text Available OBJETIVO: Avaliar a experiência global da nossa instituição com o fechamento percutâneo do canal arterial. MÉTODOS: Desde dezembro/92, 150 pacientes foram submetidos a 178 procedimentos (85 - técnica de Rashkind; 87 - coils de Gianturco; 6 - coils Duct Occlud. A mediana de idade foi de 6,5 anos (1 a 57. A média do diâmetro mínimo do canal foi de 3,05±1,24mm (1 a 8. Avaliações clínicas e ecocardiográficas foram realizadas seriadamente. RESULTADOS: Implantes adequados ocorreram em 143 (95,3% pacientes. A prevalência de shunt residual imediato foi de 52,1%, decrescendo para 15,9% no seguimento. Esta taxa caiu para 5,2% após a realização de procedimentos adicionais. Embolização de coils ocorreu em 12 procedimentos e de umbrella em 1. Um paciente apresentou hemólise e outro estenose discreta da artéria pulmonar esquerda. Não houve mortalidade. CONCLUSÃO: Esta modalidade terapêutica é segura e eficaz, proporcionando bons resultados a longo prazo.PURPOSE: To evaluate the overall experience of our institution with percutaneous occlusion of the patent ductus arteriosus. METHODS: Since December/92, 150 patients underwent 178 procedures (85 - Rashkind technique; 87 - Gianturco coils; 6 - Duct Occlud. Median age was 6.5 years (1 to 57. Mean minimum ductal diameter was 3.05±1.24mm (1 to 8. Clinical and echocardiographic evaluations were performed periodically. RESULTS: Adequate implantation was achieved in 143 (95.3% patients. Prevalence of immediate residual shunting was 52.1%, falling to 15.9% during follow-up. This figure decreased to 5.2% after new additional procedures. Umbrella and coil embolization occurred in 1 and 12 procedures, respectively. Hemolysis and mild stenosis of left pulmonary artery were observed in one patient each. There was no mortality. CONCLUSION: This therapeutic modality is safe and efficacious with good follow-up results.

Structural behaviour of pipe umbrellas in tunnel drives in granular soils; Tragverhalten von Rohrschirmdecken beim Tunnelbau im Lockergestein

Energy Technology Data Exchange (ETDEWEB)

Eckl, Michael

2012-11-01

An increase in the use of pipe umbrellas made of long piles or self drilling injection anchors can be seen in conventional tunnel drives. They are used as reinforcement ahead of the face. This paper consists of investigations concerning the structural and geotechnical behaviour of such umbrellas in granular soils. The research is based on finite element method calculations using a diverse range of essential influencing factors. From the evaluation of the calculations, conclusions can be drawn about the load bearing behaviour of the umbrellas and their interaction with the surrounding ground. A forecasting model is derived in order to predict the internal forces of the umbrella elements and a design methodology is presented. (orig.)

The relationship between childhood body weight and dental caries experience: an umbrella systematic review protocol

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Susan J. Carson

2017-10-01

Full Text Available Abstract Background Obesity and dental caries are global public health problems which can impact in childhood and throughout the life course. In simple terms, childhood dental caries and body weight are linked via the common risk factor of diet. An association between dental caries and obesity has been described in a number of studies and reviews. However, similarly, a relationship has also been noted between low body weight and caries experience in children. This protocol will provide the framework for an umbrella review to address the following question: Does the available evidence support a relationship between dental caries experience and body weight in the child population? Methods This review protocol outlines the process to carry out an umbrella systematic review which will synthesise previous reviews of childhood dental caries experience and body weight. An umbrella review methodology will be used to examine the methodological and reporting quality of existing reviews. Discussion The final umbrella review aims to aggregate the available evidence in order to provide a summary for policymakers and to inform healthcare interventions. Systematic review registration PROSPERO CRD42016047304

The relationship between childhood body weight and dental caries experience: an umbrella systematic review protocol.

Science.gov (United States)

Carson, Susan J; Abuhaloob, Lamis; Richards, Derek; Hector, Mark P; Freeman, Ruth

2017-10-25

Obesity and dental caries are global public health problems which can impact in childhood and throughout the life course. In simple terms, childhood dental caries and body weight are linked via the common risk factor of diet. An association between dental caries and obesity has been described in a number of studies and reviews. However, similarly, a relationship has also been noted between low body weight and caries experience in children. This protocol will provide the framework for an umbrella review to address the following question: Does the available evidence support a relationship between dental caries experience and body weight in the child population? This review protocol outlines the process to carry out an umbrella systematic review which will synthesise previous reviews of childhood dental caries experience and body weight. An umbrella review methodology will be used to examine the methodological and reporting quality of existing reviews. The final umbrella review aims to aggregate the available evidence in order to provide a summary for policymakers and to inform healthcare interventions. PROSPERO CRD42016047304.

Keeping parasitology under the One Health umbrella.

Science.gov (United States)

Robertson, Lucy J; Utaaker, Kjersti Selstad; Goyal, Kapil; Sehgal, Rakesh

2014-08-01

The One Health concept is no longer new, but remains an accepted concept in modern disease control - where the interactions between animal health, human health, and the environment in which we live are recognised as being of importance. However, emerging infectious diseases often garner the greatest attention and resources. Parasitic infections, many of which are zoonotic but cannot truly be considered as emerging, must ensure that they retain their place under the One Health umbrella. Copyright © 2014 Elsevier Ltd. All rights reserved.

Citizen Camera-Witnessing: A Case Study of the Umbrella Movement

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Wai Han Lo

2016-08-01

Full Text Available Citizen camera-witness is a new concept by which to describe using mobile camera phone to engage in civic expression. I argue that the meaning of this concept should not be limited to painful testimony; instead, it is a mode of civic camera-mediated mass self-testimony to brutality. The use of mobile phone recordings in Hong Kong’s Umbrella Movement is examined to understand how mobile cameras are employed as personal witnessing devices to provide recordings to indict unjust events and engage others in the civic movement. This study has examined the Facebook posts and You Tube videos of the Umbrella Movement between September 22, 2014 and December 22, 2014. The results suggest that the camera phone not only contributes to witnessing the brutal repression of the state, but also witnesses the beauty of the movement, and provides a testimony that allows for rituals to develop and semi-codes to be transformed.

Umbrella species in marine systems: using the endangered humphead wrasse to conserve coral reefs

DEFF Research Database (Denmark)

Weng, Kevin C.; Pedersen, Martin Wæver; Del Raye, Gen A.

2015-01-01

of the humphead wrasse as an umbrella species for coral reef conservation, we conducted a multi-year study of humphead wrasse home range at Palmyra Atoll, Central Tropical Pacific, tagging juvenile, female, and male individuals with acoustic transmitters. We quantified home range using 2 metrics, length and area.......4 to 14 km and changed with ontogeny. Females had larger home ranges than other reef fishes studied to date (n = 68), indicating value as an umbrella species for coral reefs. We compared the home range of the species to the size distribution of tropical marine protected areas (MPAs), and used a model...

Geological support for the Umbrella Effect as a link between geomagnetic field and climate

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Kitaba, Ikuko; Hyodo, Masayuki; Nakagawa, Takeshi; Katoh, Shigehiro; Dettman, David L.; Sato, Hiroshi

2017-01-01

The weakening of the geomagnetic field causes an increase in galactic cosmic ray (GCR) flux. Some researchers argue that enhanced GCR flux might lead to a climatic cooling by increasing low cloud formation, which enhances albedo (umbrella effect). Recent studies have reported geological evidence for a link between weakened geomagnetic field and climatic cooling. However, more work is needed on the mechanism of this link, including whether the umbrella effect is playing a central role. In this research, we present new geological evidence that GCR flux change had a greater impact on continental climate than on oceanic climate. According to pollen data from Osaka Bay, Japan, the decrease in temperature of the Siberian air mass was greater than that of the Pacific air mass during geomagnetic reversals in marine isotope stages (MIS) 19 and 31. Consequently, the summer land-ocean temperature gradient was smaller, and the summer monsoon was weaker. Greater terrestrial cooling indicates that a reduction of insolation is playing a key role in the link between the weakening of the geomagnetic field and climatic cooling. The most likely candidate for the mechanism seems to be the increased albedo of the umbrella effect. PMID:28091595

Post-Umbrella Movement: Localism and Radicalness of the Hong Kong Student Movement

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Che-po Chan

2016-08-01

Full Text Available Hong Kong student movements before the Umbrella Movement showed a political outlook of voicing within norm of the establishment, using “peaceful, rational and non-violent” approaches, acknowledging the authorities of the Hong Kong Special Administrative Region (HKSAR and mainland Chinese governments and recognizing attachment to the motherland China. Today’s new emerging political outlook of the Hong Kong student movement has a profile of anti-establishment, using more assertive means and not excluding radical behaviour, distrust of the HKSAR and mainland authorities and assertion of radical localism. In the last two years, Hong Kong students have undergone a rapid change in their orientation, resulting in today’s outlook. This paper argues that the Umbrella Movement is the key for the turnaround and it testifies to the birth of a new social and political consciousness amongst Hong Kong students.

Greater sage-grouse as an umbrella species for sagebrush-associated vertebrates.

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Mary M. Rowland; Michael J. Wisdom; Lowell Suring; Cara W. Meinke

2006-01-01

Widespread degradation of the sagebrush ecosystem in the western United States, including the invasion of cheatgrass, has prompted resource managers to consider a variety of approaches to restore and conserve habitats for sagebrush-associated species. One such approach involves the use of greater sage-grouse, a species of prominent conservation interest, as an umbrella...

Fluoropyrimidine and platinum toxicity pharmacogenetics: an umbrella review of systematic reviews and meta-analyses.

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Campbell, Jared M; Bateman, Emma; Peters, Micah Dj; Bowen, Joanne M; Keefe, Dorothy M; Stephenson, Matthew D

2016-03-01

Fluoropyrimidine (FU) and platinum-based chemotherapies are greatly complicated by their associated toxicities. This umbrella systematic review synthesized all systematic reviews that investigated associations between germline variations and toxicity, with the aim of informing personalized medicine. Systematic reviews are important in pharmacogenetics where false positives are common. Four systematic reviews were identified for FU-induced toxicity and three for platinum. Polymorphisms of DPYD and TYMS, but not MTHFR, were statistically significantly associated with FU-induced toxicity (although only DPYD had clinical significance). For platinum, GSTP1 was found to not be associated with toxicity. This umbrella systematic review has synthesized the best available evidence on the pharmacogenetics of FU and platinum toxicity. It provides a useful reference for clinicians and identifies important research gaps.

Non-target effects on songbirds from habitat manipulation for Greater Sage-Grouse: Implications for the umbrella species concept

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Carlisle, Jason D.; Chalfoun, Anna D.; Smith, Kurt T.; Beck, Jeffery L.

2018-01-01

The “umbrella species” concept is a conservation strategy in which creating and managing reserve areas to meet the needs of one species is thought to benefit other species indirectly. Broad-scale habitat protections on behalf of an umbrella species are assumed to benefit co-occurring taxa, but targeted management actions to improve local habitat suitability for the umbrella species may produce unintended effects on other species. Our objective was to quantify the effects of a common habitat treatment (mowing of big sagebrush [Artemisia tridentata]) intended to benefit a high-profile umbrella species (Greater Sage-Grouse [Centrocercus urophasianus]) on 3 sympatric songbird species of concern. We used a before–after control-impact experimental design spanning 3 yr in Wyoming, USA, to quantify the effect of mowing on the abundance, nest-site selection, nestling condition, and nest survival of 2 sagebrush-obligate songbirds (Brewer's Sparrow [Spizella breweri] and Sage Thrasher [Oreoscoptes montanus]) and one open-habitat generalist songbird (Vesper Sparrow [Pooecetes gramineus]). Mowing was associated with lower abundance of Brewer's Sparrows and Sage Thrashers but higher abundance of Vesper Sparrows. We found no Brewer's Sparrows or Sage Thrashers nesting in the mowed footprint posttreatment, which suggests complete loss of nesting habitat for these species. Mowing was associated with higher nestling condition and nest survival for Vesper Sparrows but not for the sagebrush-obligate species. Management prescriptions that remove woody biomass within a mosaic of intact habitat may be tolerated by sagebrush-obligate songbirds but are likely more beneficial for open-habitat generalist species. By definition, umbrella species conservation entails habitat protections at broad spatial scales. We caution that habitat manipulations to benefit Greater Sage-Grouse could negatively affect nontarget species of conservation concern if implemented across large spatial extents.

The macro-economic determinants of health and health inequalities-umbrella review protocol.

Science.gov (United States)

Naik, Yannish; Baker, Peter; Walker, Ian; Tillmann, Taavi; Bash, Kristin; Quantz, Darryl; Hillier-Brown, Frances; Bambra, Clare

2017-11-03

The economic determinants of health have been widely recognised as crucial factors affecting health; however, to date, no comprehensive review has been undertaken to summarise these factors and the ways in which they can influence health. We conceptualise the economy as a complex system made up of underlying approaches, regulation from institutions, markets, finance, labour, the public-private balance as well as production and distributional effects, which collectively impact on health through the effect of moderators. This protocol details the methods for an umbrella review to explore the macro-economic factors, strategies, policies and interventions that affect health outcomes and health inequalities. We will identify relevant systematic reviews using search terms derived from the Journal of Economic Literature classification. Reviews will be included if they meet the Database of Abstracts and Reviews of Effects criteria for systematic reviews. Reviews of studies with and without controls will be included; both association and intervention studies will be included. Primary outcomes will include but are not limited to morbidity, mortality, prevalence and incidence of conditions and life expectancy. Secondary outcomes will include health inequalities by gender, ethnicity or socio-economic status. Six databases will be searched using tailored versions of our piloted search strategy to locate relevant reviews. Data will be extracted using a standardized pro forma, and the findings will be synthesized into a conceptual framework to address our review aim. Our umbrella review protocol provides a robust method to systematically appraise the evidence in this field, using new conceptual models derived specifically to address the study question. This will yield important information for policymakers, practitioners and researchers at the local, national and international level. It will also help set the future research agenda in this field and guide the development of

“Expressing my attitude and doing something impossible to make it happen ...” – Listening to the Voices of Hong Kong’s Umbrella Movement Protesters

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Tim Nicholas Rühlig

2017-08-01

Full Text Available In autumn 2014 around 1.3 million mostly young citizens of Hong Kong occupied three districts of the city for 79 days. This movement became famous as the Umbrella Movement. Initially, the Umbrella Movement was almost exclusively perceived as a pro-democracy occupation because the democratization of the city’s polity was its core demand. However, over time the perception shifted and the movement was increasingly portrayed as part of a growing demand for more autonomy from mainland China. This rising “localism” is often associated with anti-Chinese sentiments including racism. This article aims to demonstrate that the Umbrella Movement’s call for democracy is indeed part of a broader agenda for more self-determination. This agenda, however, is not necessarily racist. Instead, the Umbrella Movement was a very plural one. The Umbrella Movement’s agenda does, however, comprise not only questions of democratization but also three additional dimensions, namely socio-economic, identity-political and institutional issues. The article aims to present the plurality of the Umbrella Movement by referring to and quoting a multitude of interviews with protesters which are intended to give the occupiers a “voice” in all their diversity. Finally, the article aims to conclude on the achievements of the movement in all four dimensions and outlines possible future directions.

Imaging of oxygen gradients in giant umbrella cells: an ex vivo PLIM study.

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Zhdanov, A V; Golubeva, A V; Okkelman, I A; Cryan, J F; Papkovsky, D B

2015-10-01

O2 plays a pivotal role in aerobic metabolism and regulation of cell and tissue function. Local differences and fluctuations in tissue O2 levels are well documented; however, the physiological significance of O2 microgradients, particularly at the subcellular level, remains poorly understood. Using the cell-penetrating phosphorescent O2 probe Pt-Glc and confocal fluorescence microscopy, we visualized O2 distribution in individual giant (>100-μm) umbrella cells located superficially in the urinary bladder epithelium. We optimized conditions for in vivo phosphorescent staining of the inner surface of the mouse bladder and subsequent ex vivo analysis of excised live tissue. Imaging experiments revealed significant (≤85 μM) and heterogeneous deoxygenation within respiring umbrella cells, with radial O2 gradients of up to 40 μM across the cell, or ∼0.6 μM/μm. Deeply deoxygenated (5-15 μM O2) regions were seen to correspond to the areas enriched with polarized mitochondria. Pharmacological activation of mitochondrial respiration decreased oxygenation and O2 gradients in umbrella cells, while inhibition with antimycin A dissipated the gradients and caused gradual reoxygenation of the tissue to ambient levels. Detailed three-dimensional maps of O2 distribution potentially can be used for the modeling of intracellular O2-dependent enzymatic reactions and downstream processes, such as hypoxia-inducible factor signaling. Further ex vivo and in vivo studies on intracellular and tissue O2 gradients using confocal imaging can shed light on the molecular mechanisms regulating O2-dependent (patho)physiological processes in the bladder and other tissues. Copyright © 2015 the American Physiological Society.

Creative Experience and Revisit Intention of Handmade Oriental Parasol Umbrella in Kaohsiung

OpenAIRE

Yi-Ju Lee

2015-01-01

This study identified the hypothesised relationship between creative experience, and revisit intention of handmade oriental parasol umbrella in Kaohsiung, Taiwan. A face-to-face questionnaire survey was administered in Meinong town, Kaohsiung. The components of creative experience were found as "sense of achievement", "unique learning" and "interaction with instructors" in creative tourism. The result also revealed significant positive relationships between creative exper...

Study on the Application of the Combination of TMD Simulation and Umbrella Sampling in PMF Calculation for Molecular Conformational Transitions

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Qing Wang

2016-05-01

Full Text Available Free energy calculations of the potential of mean force (PMF based on the combination of targeted molecular dynamics (TMD simulations and umbrella samplings as a function of physical coordinates have been applied to explore the detailed pathways and the corresponding free energy profiles for the conformational transition processes of the butane molecule and the 35-residue villin headpiece subdomain (HP35. The accurate PMF profiles for describing the dihedral rotation of butane under both coordinates of dihedral rotation and root mean square deviation (RMSD variation were obtained based on the different umbrella samplings from the same TMD simulations. The initial structures for the umbrella samplings can be conveniently selected from the TMD trajectories. For the application of this computational method in the unfolding process of the HP35 protein, the PMF calculation along with the coordinate of the radius of gyration (Rg presents the gradual increase of free energies by about 1 kcal/mol with the energy fluctuations. The feature of conformational transition for the unfolding process of the HP35 protein shows that the spherical structure extends and the middle α-helix unfolds firstly, followed by the unfolding of other α-helices. The computational method for the PMF calculations based on the combination of TMD simulations and umbrella samplings provided a valuable strategy in investigating detailed conformational transition pathways for other allosteric processes.

Umbrellas can work under water: Using threatened species as indicator and management surrogates can improve coastal conservation

Science.gov (United States)

Gilby, Ben L.; Olds, Andrew D.; Connolly, Rod M.; Yabsley, Nicholas A.; Maxwell, Paul S.; Tibbetts, Ian R.; Schoeman, David S.; Schlacher, Thomas A.

2017-12-01

Species surrogates, the use of particular species to index habitat condition or to represent ecological assemblages are commonly identified in many ecosystems, but are less tested, and therefore less employed in estuaries. Estuaries provide important ecosystem goods (e.g. harvestable species) and services (e.g. carbon processing, coastal armouring), but require protection from multiple human activities, meaning that finding surrogates for estuarine condition or faunal assemblages is a significant knowledge gap. In this study, we test the efficacy of the threatened estuary ray Hemitrygon fluviorum, as a suitable indicator of ecosystem condition and management umbrella surrogate species for conservation prioritisation and monitoring purposes within estuaries. We surveyed fish assemblages and ray presence at ten sites within each of 22 estuaries in southeast Queensland, Australia, using one hour deployments of baited video arrays. We then tested for correlations between ray presence, a series of environmental variables considered important to ecosystem management within estuaries (i.e. testing rays as indicator species), and the co-occurring fish species (i.e. testing rays as umbrella species). Estuary rays function as both umbrella species and ecological indicators of habitat status in subtropical Australian estuaries. As umbrellas, ray occurrence concords with elevated species richness. As ecological indicators, ray distribution concords with habitats of good water quality (especially low turbidity) and more natural vegetation remaining in the catchment. These results highlight the potential for other threatened aquatic vertebrates that are both readily detectable and that are reliable proxies for ecosystems status to be become useful management tools in estuaries. The protection of such large, threatened species in coastal seascapes allows managers to address multiple targets for conservation, especially; (1) protecting species of conservation concern; (2

The macro-economic determinants of health and health inequalities—umbrella review protocol

Directory of Open Access Journals (Sweden)

Yannish Naik

2017-11-01

Full Text Available Abstract Background The economic determinants of health have been widely recognised as crucial factors affecting health; however, to date, no comprehensive review has been undertaken to summarise these factors and the ways in which they can influence health. We conceptualise the economy as a complex system made up of underlying approaches, regulation from institutions, markets, finance, labour, the public-private balance as well as production and distributional effects, which collectively impact on health through the effect of moderators. This protocol details the methods for an umbrella review to explore the macro-economic factors, strategies, policies and interventions that affect health outcomes and health inequalities. Methods We will identify relevant systematic reviews using search terms derived from the Journal of Economic Literature classification. Reviews will be included if they meet the Database of Abstracts and Reviews of Effects criteria for systematic reviews. Reviews of studies with and without controls will be included; both association and intervention studies will be included. Primary outcomes will include but are not limited to morbidity, mortality, prevalence and incidence of conditions and life expectancy. Secondary outcomes will include health inequalities by gender, ethnicity or socio-economic status. Six databases will be searched using tailored versions of our piloted search strategy to locate relevant reviews. Data will be extracted using a standardized pro forma, and the findings will be synthesized into a conceptual framework to address our review aim. Discussion Our umbrella review protocol provides a robust method to systematically appraise the evidence in this field, using new conceptual models derived specifically to address the study question. This will yield important information for policymakers, practitioners and researchers at the local, national and international level. It will also help set the future

The Mobilization of Memory and Tradition: Hong Kong’s Umbrella Movement and Beijing’s 1989 Tiananmen Movement

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Johan Lagerkvist

2016-08-01

Full Text Available The 2014 Umbrella Movement in Hong Kong has been the most important pro-democracy protest on Chinese soil since the rise and fall of the Tiananmen Movement of 1989. Moreover, the 1989 Beijing Massacre has politicized a generation of pro-democracy activists in Hong Kong that has shaped Hong Kong’s vibrant civil society. However, while this “Tiananmen generation” has been crucial for the preparation and initial stage of the Umbrella Movement, the actual occupation was dominated by a new generation that is almost exclusively concerned with local Hong Kong politics. In light of this background, this paper compares the two democracy movements. The external environment and the goals of the two movements are markedly different. However, our comparison demonstrates striking similarities between the two movements, e.g. their internal structure and framing. Moreover, what we see as the “mobilization of memory” reflects both the continued importance of civil society structures that have been shaped by the “Tiananmen veterans” as well as the on-going renegotiation of the SAR’s relationship with the Mainland. Finally, these findings entail that the Chinese party-state will need to utilize different means to pacify the Umbrella Movement than what was done to placate democracy activists after the 1989 crackdown.

The role of the umbrella inversion mode in proton diffusion

Science.gov (United States)

Hassanali, Ali A.; Giberti, Federico; Sosso, Gabriele C.; Parrinello, Michele

2014-04-01

Here, using ab initio molecular dynamics (AIMD) simulations, we elucidate the role of the umbrella inversion mode of the hydronium in proton transfer (PT) in liquid water. The hydrophobic face of the hydronium oxygen experiences asymmetries in the solvent potential along the inversion coordinate and this has a rather drastic effect on the barrier for proton transfer. This behavior is coupled to the fluctuations of voids or cavities in the vicinity of the hydronium in the water network. The peculiar inversion mode can either trap or release the proton from different parts of the water network.

What causes psychosis? An umbrella review of risk and protective factors

Science.gov (United States)

Radua, Joaquim; Ramella‐Cravaro, Valentina; Ioannidis, John P.A.; Reichenberg, Abraham; Phiphopthatsanee, Nacharin; Amir, Taha; Yenn Thoo, Hyi; Oliver, Dominic; Davies, Cathy; Morgan, Craig; McGuire, Philip; Murray, Robin M.; Fusar‐Poli, Paolo

2018-01-01

Psychosis is a heterogeneous psychiatric condition for which a multitude of risk and protective factors have been suggested. This umbrella review aimed to classify the strength of evidence for the associations between each factor and psychotic disorders whilst controlling for several biases. The Web of Knowledge database was searched to identify systematic reviews and meta‐analyses of observational studies which examined associations between socio‐demographic, parental, perinatal, later factors or antecedents and psychotic disorders, and which included a comparison group of healthy controls, published from 1965 to January 31, 2017. The literature search and data extraction followed PRISMA and MOOSE guidelines. The association between each factor and ICD or DSM diagnoses of non‐organic psychotic disorders was graded into convincing, highly suggestive, suggestive, weak, or non‐significant according to a standardized classification based on: number of psychotic cases, random‐effects p value, largest study 95% confidence interval, heterogeneity between studies, 95% prediction interval, small study effect, and excess significance bias. In order to assess evidence for temporality of association, we also conducted sensitivity analyses restricted to data from prospective studies. Fifty‐five meta‐analyses or systematic reviews were included in the umbrella review, corresponding to 683 individual studies and 170 putative risk or protective factors for psychotic disorders. Only the ultra‐high‐risk state for psychosis (odds ratio, OR=9.32, 95% CI: 4.91‐17.72) and Black‐Caribbean ethnicity in England (OR=4.87, 95% CI: 3.96‐6.00) showed convincing evidence of association. Six factors were highly suggestive (ethnic minority in low ethnic density area, second generation immigrants, trait anhedonia, premorbid IQ, minor physical anomalies, and olfactory identification ability), and nine were suggestive (urbanicity, ethnic minority in high ethnic density area

New urban players: stratagematic use of media by Banksy and the Hong Kong Umbrella Movement

NARCIS (Netherlands)

Monachesi, P.|info:eu-repo/dai/nl/145655148; Turco, M.|info:eu-repo/dai/nl/304842710

2017-01-01

In this article, we focus on two urban players whose ultimate aim is to regain public space both in the digital and the urban context: the street artist Banksy and the Hong Kong Umbrella Movement. These two apparently very different players in fact present similar characteristics and operate in

Umbrella sampling of proton transfer in a creatine-water system

Science.gov (United States)

Ivchenko, Olga; Bachert, Peter; Imhof, Petra

2014-04-01

Proton transfer reactions are among the most common processes in chemistry and biology. Proton transfer between creatine and surrounding solvent water is underlying the chemical exchange saturation transfer used as a contrast in magnetic resonance imaging. The free energy barrier, determined by first-principles umbrella sampling simulations (EaDFT 3 kcal/mol) is in the same order of magnitude as the experimentally obtained activation energy. The underlying mechanism is a first proton transfer from the guanidinium group to the water pool, followed by a second transition where a proton is "transferred back" from the nearest water molecule to the deprotonated nitrogen atom of creatine.

Quality Assurance and Evaluation through Brazilian Lenses: An Exploration into the Validity of Umbrella Concepts

Science.gov (United States)

Centeno, Vera G.; Kauko, Jaakko; Candido, Helena H. D.

2018-01-01

In our present research we address the question of whether it is valid to apply the Quality Assurance and Evaluation (QAE) umbrella concept, which was formulated to explain new phenomena in European educational governance, to similar developments in Brazilian basic education. This led us to reflect on the possible pitfalls and potential strengths…

Non-equilibrium umbrella sampling applied to force spectroscopy of soft matter.

Science.gov (United States)

Gao, Y X; Wang, G M; Williams, D R M; Williams, Stephen R; Evans, Denis J; Sevick, E M

2012-02-07

Physical systems often respond on a timescale which is longer than that of the measurement. This is particularly true in soft matter where direct experimental measurement, for example in force spectroscopy, drives the soft system out of equilibrium and provides a non-equilibrium measure. Here we demonstrate experimentally for the first time that equilibrium physical quantities (such as the mean square displacement) can be obtained from non-equilibrium measurements via umbrella sampling. Our model experimental system is a bead fluctuating in a time-varying optical trap. We also show this for simulated force spectroscopy on a complex soft molecule--a piston-rotaxane.

Efficient Determination of Free Energy Landscapes in Multiple Dimensions from Biased Umbrella Sampling Simulations Using Linear Regression.

Science.gov (United States)

Meng, Yilin; Roux, Benoît

2015-08-11

The weighted histogram analysis method (WHAM) is a standard protocol for postprocessing the information from biased umbrella sampling simulations to construct the potential of mean force with respect to a set of order parameters. By virtue of the WHAM equations, the unbiased density of state is determined by satisfying a self-consistent condition through an iterative procedure. While the method works very effectively when the number of order parameters is small, its computational cost grows rapidly in higher dimension. Here, we present a simple and efficient alternative strategy, which avoids solving the self-consistent WHAM equations iteratively. An efficient multivariate linear regression framework is utilized to link the biased probability densities of individual umbrella windows and yield an unbiased global free energy landscape in the space of order parameters. It is demonstrated with practical examples that free energy landscapes that are comparable in accuracy to WHAM can be generated at a small fraction of the cost.

Sampling free energy surfaces as slices by combining umbrella sampling and metadynamics.

Science.gov (United States)

Awasthi, Shalini; Kapil, Venkat; Nair, Nisanth N

2016-06-15

Metadynamics (MTD) is a very powerful technique to sample high-dimensional free energy landscapes, and due to its self-guiding property, the method has been successful in studying complex reactions and conformational changes. MTD sampling is based on filling the free energy basins by biasing potentials and thus for cases with flat, broad, and unbound free energy wells, the computational time to sample them becomes very large. To alleviate this problem, we combine the standard Umbrella Sampling (US) technique with MTD to sample orthogonal collective variables (CVs) in a simultaneous way. Within this scheme, we construct the equilibrium distribution of CVs from biased distributions obtained from independent MTD simulations with umbrella potentials. Reweighting is carried out by a procedure that combines US reweighting and Tiwary-Parrinello MTD reweighting within the Weighted Histogram Analysis Method (WHAM). The approach is ideal for a controlled sampling of a CV in a MTD simulation, making it computationally efficient in sampling flat, broad, and unbound free energy surfaces. This technique also allows for a distributed sampling of a high-dimensional free energy surface, further increasing the computational efficiency in sampling. We demonstrate the application of this technique in sampling high-dimensional surface for various chemical reactions using ab initio and QM/MM hybrid molecular dynamics simulations. Further, to carry out MTD bias reweighting for computing forward reaction barriers in ab initio or QM/MM simulations, we propose a computationally affordable approach that does not require recrossing trajectories. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Looking beyond rare species as umbrella species: Northern Bobwhites (Colinus virginianus) and conservation of grassland and shrubland birds

Science.gov (United States)

Crosby, Andrew D.; Elmore, R.D.; Leslie,, David M.; Will, Rodney E.

2015-01-01

Changes in land use and land cover throughout the eastern half of North America have caused substantial declines in populations of birds that rely on grassland and shrubland vegetation types, including socially and economically important game birds such as the Northern Bobwhite (Colinus virginianus; hereafter bobwhites). As much attention is focused on habitat management and restoration for bobwhites, they may act as an umbrella species for other bird species with similar habitat requirements. We quantified the relationship of bobwhites to the overall bird community and evaluated the potential for bobwhites to act as an umbrella species for grassland and shrubland birds. We monitored bobwhite presence and bird community composition within 31 sample units on selected private lands in the south-central United States from 2009 to 2011. Bobwhites were strongly associated with other grassland and shrubland birds and were a significant positive predictor for 9 species. Seven of these, including Bell's Vireo (Vireo bell), Dicksissel (Spiza americana), and Grasshopper Sparrow (Ammodramus savannarum), are listed as species of conservation concern. Species richness and occupancy probability of grassland and shrubland birds were higher relative to the overall bird community in sample units occupied by bobwhites. Our results show that bobwhites can act as an umbrella species for grassland and shrubland birds, although the specific species in any given situation will depend on region and management objectives. These results suggest that efficiency in conservation funding can be increased by using public interest in popular game species to leverage resources to meet multiple conservation objectives.

Rare behavior of growth processes via umbrella sampling of trajectories

Science.gov (United States)

Klymko, Katherine; Geissler, Phillip L.; Garrahan, Juan P.; Whitelam, Stephen

2018-03-01

We compute probability distributions of trajectory observables for reversible and irreversible growth processes. These results reveal a correspondence between reversible and irreversible processes, at particular points in parameter space, in terms of their typical and atypical trajectories. Thus key features of growth processes can be insensitive to the precise form of the rate constants used to generate them, recalling the insensitivity to microscopic details of certain equilibrium behavior. We obtained these results using a sampling method, inspired by the "s -ensemble" large-deviation formalism, that amounts to umbrella sampling in trajectory space. The method is a simple variant of existing approaches, and applies to ensembles of trajectories controlled by the total number of events. It can be used to determine large-deviation rate functions for trajectory observables in or out of equilibrium.

Coffee, Caffeine, and Health Outcomes: An Umbrella Review.

Science.gov (United States)

Grosso, Giuseppe; Godos, Justyna; Galvano, Fabio; Giovannucci, Edward L

2017-08-21

To evaluate the associations between coffee and caffeine consumption and various health outcomes, we performed an umbrella review of the evidence from meta-analyses of observational studies and randomized controlled trials (RCTs). Of the 59 unique outcomes examined in the selected 112 meta-analyses of observational studies, coffee was associated with a probable decreased risk of breast, colorectal, colon, endometrial, and prostate cancers; cardiovascular disease and mortality; Parkinson's disease; and type-2 diabetes. Of the 14 unique outcomes examined in the 20 selected meta-analyses of observational studies, caffeine was associated with a probable decreased risk of Parkinson's disease and type-2 diabetes and an increased risk of pregnancy loss. Of the 12 unique acute outcomes examined in the selected 9 meta-analyses of RCTs, coffee was associated with a rise in serum lipids, but this result was affected by significant heterogeneity, and caffeine was associated with a rise in blood pressure. Given the spectrum of conditions studied and the robustness of many of the results, these findings indicate that coffee can be part of a healthful diet.

A Newly Developed Perfused Umbrella Electrode for Radiofrequency Ablation: An Ex Vivo Evaluation Study in Bovine Liver

International Nuclear Information System (INIS)

Bruners, Philipp; Pfeffer, Jochen; Kazim, Rana M.; Guenther, Rolf W.; Schmitz-Rode, Thomas; Mahnken, Andreas H.

2007-01-01

The purpose of this study was to evaluate the effectiveness of a newly developed perfused monopolar radiofrequency (RF) probe with an umbrella-shaped array. A perfused umbrella-shaped monopolar RF probe based on a LeVeen electrode (Boston Scientific Corp., Natick, MA, USA) with a 3-cm array diameter was developed. Five different configurations of this electrode were tested: (a) perfusion channel/endhole, (b) perfusion channel/endhole + sideholes, (c) 1 cm insulation removed at the tip, (d) 1 cm insulation removed at the tip + perfusion channel/endhole, and (e) 1 cm insulation removed at the tip + perfusion channel/endhole + sideholes. An unmodified LeVeen electrode served as a reference standard. RF ablations were performed in freshly excised bovine liver using a commercial monopolar RF system with a 200-W generator (RF 3000; Boston Scientific Corp.). Each electrode was tested 10 times applying the vendor's recommended ablation protocol combined with the preinjection of 2 ml 0.9% saline. Volumes and shapes of the lesions were compared. Lesions generated with the original LeVeen electrode showed a mean volume of 12.74 ± 0.52 cm 3 . Removing parts of the insulation led to larger coagulation volumes (22.65 ± 2.12 cm 3 ). Depending on the configuration, saline preinjection resulted in a further increase in coagulation volume (25.22 ± 3.37 to 31.28 ± 2.32 cm 3 ). Besides lesion volume, the shape of the ablation zone was influenced by the configuration of the electrode used. We conclude that saline preinjection in combination with increasing the active tip length of the umbrella-shaped LeVeen RF probe allows the reliable ablation of larger volumes in comparison to the originally configured electrode

Nanomolar Cellular Antisense Activity of Peptide Nucleic Acid (PNA) Cholic Acid ("Umbrella") and Cholesterol Conjugates Delivered by Cationic Lipids

DEFF Research Database (Denmark)

Shiraishi, Takehiko; Nielsen, Peter E

2012-01-01

of cholesterol and cholic acid ("umbrella") derivatives of splice correction antisense PNA oligomers. While the conjugates alone were practically inactive up to 1 µM, their activity was dramatically improved when delivered by a cationic lipid transfection agent (LipofectAMINE2000). In particular, PNAs...

Methotrexate-induced toxicity pharmacogenetics: an umbrella review of systematic reviews and meta-analyses.

Science.gov (United States)

Campbell, Jared M; Bateman, Emma; Stephenson, Matthew D; Bowen, Joanne M; Keefe, Dorothy M; Peters, Micah D J

2016-07-01

Methotrexate chemotherapy is associated with various toxicities which can result in the interruption or discontinuation of treatment and a subsequently raised risk of relapse. This umbrella systematic review was conducted to synthesize the results of all existing systematic reviews that investigate the pharmacogenetics of methotrexate-induced toxicity, with the aim of developing a comprehensive reference for personalized medicine. Databases searched were PubMed, Embase, JBI Database of Systematic Reviews and Implementation Reports, DARE, and ProQuest. Papers were critically appraised by two reviewers, and data were extracted using a standardized tool. Three systematic reviews on methotrexate-induced toxicity were included in the review. Meta-analyses were reported across Asian, Caucasian, pediatric and adult patients for the MTHFR C677T and A1298C polymorphisms. Toxicity outcomes included different forms of hematologic, ectodermal and hepatic toxicities. Results varied considerably depending on the patient groups and subgroups investigated in the different systematic reviews, as well as the genetic models utilized. However, significant associations were found between the MTHFR C677T allele and; hepatic toxicity, myelosuppression, oral mucositis, gastrointestinal toxicity, and skin toxicity. Additionally, limited evidence suggests that the MTHFR A1298C polymorphism may be associated with decreased risk of skin toxicity and leukopenia. This umbrella systematic review has synthesized the best available evidence on the pharmacogenetics of methotrexate toxicity. The next step in making personalized medicine for methotrexate therapy a clinical reality is research on the effectiveness and cost-effectiveness of MTHFR genotype testing to enable the close monitoring of at-risk patients for the timely initiation of rescue therapies.

Comparison of clinical outcomes of multi-point umbrella suturing and single purse suturing with two-point traction after procedure for prolapse and hemorrhoids (PPH) surgery.

Science.gov (United States)

Jiang, Huiyong; Hao, Xiuyan; Xin, Ying; Pan, Youzhen

2017-11-01

To compare the clinical outcomes of multipoint umbrella suture and single-purse suture with two-point traction after procedure for prolapse and hemorrhoids surgery (PPH) for the treatment of mixed hemorrhoids. Ninety patients were randomly divided into a PPH plus single-purse suture group (Group A) and a PPH plus multipoint umbrella suture (Group B). All operations were performed by an experienced surgeon. Operation time, width of the specimen, hemorrhoids retraction extent, postoperative pain, postoperative bleeding, and length of hospitalization were recorded and compared. Statistical analysis was conducted by t-test and χ2 test. There were no significant differences in sex, age, course of disease, and degree of prolapse of hemorrhoids between the two groups. The operative time in Group A was significantly shorter than that in Group B (P hemorrhoid core retraction were significantly lower in Group B (P  0.05 for all comparisons) was observed. The multipoint umbrella suture showed better clinical outcomes because of its targeted suture according to the extent of hemorrhoid prolapse. Copyright © 2017. Published by Elsevier Ltd.

Cross-sector Service Provision in Health and Social Care: An Umbrella Review.

Science.gov (United States)

Winters, Shannon; Magalhaes, Lilian; Anne Kinsella, Elizabeth; Kothari, Anita

2016-04-08

Meeting the complex health needs of people often requires interaction among numerous different sectors. No one service can adequately respond to the diverse care needs of consumers. Providers working more effectively together is frequently touted as the solution. Cross-sector service provision is defined as independent, yet interconnected sectors working together to better meet the needs of consumers and improve the quality and effectiveness of service provision. Cross-sector service provision is expected, yet much remains unknown about how it is conceptualised or its impact on health status. This umbrella review aims to clarify the critical attributes that shape cross-sector service provision by presenting the current state of the literature and building on the findings of the 2004 review by Sloper. Literature related to cross-sector service provision is immense, which poses a challenge for decision makers wishing to make evidence-informed decisions. An umbrella review was conducted to articulate the overall state of cross-sector service provision literature and examine the evidence to allow for the discovery of consistencies and discrepancies across the published knowledge base. Sixteen reviews met the inclusion criteria. Seven themes emerged: Focusing on the consumer, developing a shared vision of care, leadership involvement, service provision across the boundaries, adequately resourcing the arrangement, developing novel arrangements or aligning with existing relationships, and strengthening connections between sectors. Future research from a cross-organisational, rather than individual provider, perspective is needed to better understand what shapes cross-sector service provision at the boundaries. Findings aligned closely with the work done by Sloper and raise red flags related to reinventing what is already known. Future researchers should look to explore novel areas rather than looking into areas that have been explored at length. Evaluations of out

Effects of Rolling and Cooling Conditions on Microstructure of Umbrella-Bone Steel

Science.gov (United States)

Wu, Yan-Xin; Fu, Jian-Xun; Zhang, Hua; Xu, Jie; Zhai, Qi-Jie

2017-10-01

The effects of deformation temperature and cooling rate on the micro-structure evolution of umbrella-bone steel was investigated using a Gleeble thermal-mechanical testing machine and dynamic continuous cooling transformation (CCT) curves. The results show that fast cooling which lowers the starting temperature of ferrite transformation leads to finer ferrite grains and more pearlite. Low temperature deformation enhances the hardening effect of austenite and reduces hardenability, allowing a wider range of cooling rates and thus avoiding martensite transformation after deformation. According to the phase transformation rules, the ultimate tensile strength and reduction in area of the wire rod formed in the optimized industrial trial are 636 MPa and 73.6 %, respectively, showing excellent strength and plasticity.

An umbrella review of garlic intake and risk of cardiovascular disease.

Science.gov (United States)

Schwingshackl, Lukas; Missbach, Benjamin; Hoffmann, Georg

2016-10-15

To gain further insight into the strength of evidence and extent of possible biases in the scope of studies investigating the impact of garlic and garlic supplement intake on biomarkers of cardiovascular disease, we performed an umbrella review of all published meta-analyses synthesizing data from both observational studies and randomized controlled trials. Electronic database PubMed (between 1966 and June 2015) was searched for systematic reviews and meta-analyses using following search terms: ("garlic" OR "allium sativum" OR "allicin" OR "organosulfur") AND ("cardiovascular" OR "coronary" OR "cholesterol" OR "triglyceride" OR "atherosclerosis" OR "blood pressure" OR "hypertension" OR "blood glucose") AND ("systematic review" OR "meta-analysis"), with no restriction to calendar data and language. Hand-search of reference lists and relevant clinical guidelines was performed as well. Nine systematic reviews investigated the effects of garlic on lipid parameters and eight systematic reviews analyzed the effects on blood pressure parameters were identified. Eight of nine meta-analyses synthesizing the effect of garlic on blood lipids reported significantly decreased total cholesterol levels. Inconsistent results could be detected for HDL-cholestrol, LDL-cholesterol, and triacylglycerols. The effect of garlic on systolic blood pressure showed consistent results across publications with 7 out of 8 meta-analyses demonstrating a substantial decrease in systolic blood pressure. Similar results could be reported regarding the effect of garlic on diastolic blood pressure, i.e. 6 out of 8 meta-analyses detected significant reductions in diastolic blood pressure levels following interventions with garlic. According to the data summarized in the present umbrella review, garlic preparations as well as garlic exerted some positive effects on indicators and biomarkers of cardiovascular disease, typically without causing any serious side effects. However, with regard to the

Cross-sector Service Provision in Health and Social Care: An Umbrella Review

Directory of Open Access Journals (Sweden)

Shannon Winters

2016-04-01

Full Text Available Introduction: Meeting the complex health needs of people often requires interaction among numerous different sectors. No one service can adequately respond to the diverse care needs of consumers. Providers working more effectively together is frequently touted as the solution. Cross-sector service provision is defined as independent, yet interconnected sectors working together to better meet the needs of consumers and improve the quality and effectiveness of service provision. Cross-sector service provision is expected, yet much remains unknown about how it is conceptualised or its impact on health status. This umbrella review aims to clarify the critical attributes that shape cross-sector service provision by presenting the current state of the literature and building on the findings of the 2004 review by Sloper. Methods: Literature related to cross-sector service provision is immense, which poses a challenge for decision makers wishing to make evidence-informed decisions. An umbrella review was conducted to articulate the overall state of cross-sector service provision literature and examine the evidence to allow for the discovery of consistencies and discrepancies across the published knowledge base. Findings: Sixteen reviews met the inclusion criteria. Seven themes emerged: Focusing on the consumer, developing a shared vision of care, leadership involvement, service provision across the boundaries, adequately resourcing the arrangement, developing novel arrangements or aligning with existing relationships, and strengthening connections between sectors. Future research from a cross-organisational, rather than individual provider, perspective is needed to better understand what shapes cross-sector service provision at the boundaries. Conclusion: Findings aligned closely with the work done by Sloper and raise red flags related to reinventing what is already known. Future researchers should look to explore novel areas rather than looking into

Umbrella Wheel - a stair-climbing and obstacle-handling wheel design concept

DEFF Research Database (Denmark)

Iversen, Simon; Jouffroy, Jerome

2017-01-01

This paper proposes a new design for stair-climbing using a wheel that can split into segments and walk up stairs or surmount other obstacles often found where humans traverse, while still being able to retain a perfectly round shape for traveling on smooth ground. Using this change of configurat......This paper proposes a new design for stair-climbing using a wheel that can split into segments and walk up stairs or surmount other obstacles often found where humans traverse, while still being able to retain a perfectly round shape for traveling on smooth ground. Using this change...... of configuration, staircases with a wide range of dimensions can be covered efficiently and safely. The design, named Umbrella Wheel, can consist of as many wheel segments as desired, and as few as two. A smaller or higher number of wheel segments has advantages and disadvantages depending on the specific...

New silicate-germanate Cs2Pb2[(Si0.6Ge0.4)2O7] from the series A2Pb2[B2O7], A = K, Cs, B = Si, Ge with the umbrella-like [PbO3]4- group

Science.gov (United States)

Belokoneva, Elena L.; Morozov, Ivan A.; Volkov, Anatoly S.; Dimitrova, Olga V.; Stefanovich, Sergey Yu.

2018-04-01

New silicate-germanate Cs2Pb2[(Si0.6Ge0.4)2O7] was synthesized in multi-components hydrothermal solution with 20 w.% concentration of Cs2CO3 mineralizer, pH = 10. Novel mixed compound belongs to the structure type A2Pb2[B2O7] previously indicated for powders with A = K, B=Si or Ge. Singe crystal structure determination of Cs2Pb2[(Si0.6Ge0.4)2O7] revealed the need for the correction of the space group of the earlier suggested structural model from P-3 to P-3m1, as well as for the splitting of the Pb-atom position. Umbrella-like groups [PbO3]4- are located between [(Si,Ge)O4]4- tetrahedra in mica-like honeycomb layers and play the role of tetrahedra with the Pb-lone-pair as the forth apex. Crystal chemical comparison revealed similarities and differences with the classical structure type of α-celsian Ba[Al2Si2O8] with the tetrahedral double layer. Recently investigated nonlinear optical acentric borates Pb2(BO3)(NO3) and Pb2(BO3)Cl are both related to this structural type, possessing umbrella-like groups [PbO3]4- and honeycomb layers [Pb2(BO3)]+ with the BO3-triangles on the tetrahedral positions.

Single venom-based immunotherapy effectively protects patients with double positive tests to honey bee and Vespula venom

Science.gov (United States)

2013-01-01

Background Referring to individuals with reactivity to honey bee and Vespula venom in diagnostic tests, the umbrella terms “double sensitization” or “double positivity” cover patients with true clinical double allergy and those allergic to a single venom with asymptomatic sensitization to the other. There is no international consensus on whether immunotherapy regimens should generally include both venoms in double sensitized patients. Objective We investigated the long-term outcome of single venom-based immunotherapy with regard to potential risk factors for treatment failure and specifically compared the risk of relapse in mono sensitized and double sensitized patients. Methods Re-sting data were obtained from 635 patients who had completed at least 3 years of immunotherapy between 1988 and 2008. The adequate venom for immunotherapy was selected using an algorithm based on clinical details and the results of diagnostic tests. Results Of 635 patients, 351 (55.3%) were double sensitized to both venoms. The overall re-exposure rate to Hymenoptera stings during and after immunotherapy was 62.4%; the relapse rate was 7.1% (6.0% in mono sensitized, 7.8% in double sensitized patients). Recurring anaphylaxis was statistically less severe than the index sting reaction (P = 0.004). Double sensitization was not significantly related to relapsing anaphylaxis (P = 0.56), but there was a tendency towards an increased risk of relapse in a subgroup of patients with equal reactivity to both venoms in diagnostic tests (P = 0.15). Conclusions Single venom-based immunotherapy over 3 to 5 years effectively and long-lastingly protects the vast majority of both mono sensitized and double sensitized Hymenoptera venom allergic patients. Double venom immunotherapy is indicated in clinically double allergic patients reporting systemic reactions to stings of both Hymenoptera and in those with equal reactivity to both venoms in diagnostic tests who have not reliably identified the

A quantitative evaluation of the conservation umbrella of spotted owl management areas in the Sierra Nevada.

Directory of Open Access Journals (Sweden)

Ryan D Burnett

Full Text Available Whether by design or default, single species management often serves as an umbrella for species with similar habitat requirements. In recent decades the focus of National Forest management in the Sierra Nevada of California has shifted towards increasing closed canopy mature forest conditions through the protection of areas occupied by the California Spotted Owl (Strix occidentalis occidentalis. To evaluate the implications of these habitat changes and the potential umbrella resulting from a system of owl reserves on the broader avian community, we estimated occupancy of birds inside and outside of Spotted Owl Home Range Core Areas in northeastern California. We used point count data in a multi-species hierarchical Bayesian model incorporating the detection history of 81 species over a two-year time period (2005-2006. A small set of vegetation cover and topography covariates were included in the model to account for broad differences in habitat conditions, as well as a term identifying whether or not a site was within a Core Area. Seventeen species had a negative Core Area effect, seven had a positive effect, and the rest were not significant. Estimated species richness was significantly different with 23.1 species per 100 m radius circle outside Core Areas and 21.7 inside Core Areas. The majority of the species negatively associated with Core Areas are tied to early successional and other disturbance-dependent habitats. Conservation and climate vulnerability rankings were mixed. On average we found higher scores (greater risk for the species positively associated with Core Areas, but a larger number of species with the highest scores were negatively associated with Core Areas. We discuss the implications for managing the Sierra Nevada ecosystem and illustrate the role of monitoring broader suites of species in guiding management of large complex ecosystems.

Iranian Parents' Supportive Umbrella during their Children Surgery: a Qualitative Study

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Fatemeh Valizadeh

2016-03-01

Full Text Available Background Being in a position of vulnerability, distress and uncertainty reduces the ability of the parents to protect their children and makes them need support from others. The first step to aid clients more is to identify their supportive sources. This study aimed to determine parents' experiences of supportive sources during their children surgery. Materials and Methods This is a descriptive qualitative research. Purposive and maximum variation sampling applied to select 21 parents of operated children in Ahvaz hospitals, Iran. Semi structured interviews, with open question were used to data collection. Audio recording interviews put into written form word by word and finally analyzed with qualitative content analysis approach.  Results Parents considered the personnel's beyond-task-orientation performance, family comprehensive support, mutual facilitating of peers and the elixir of connection to God as the sources that supported them as an umbrella during their children surgery.     Conclusion It is essential for the health service providers to check each family thoroughly in terms of other supportive sources while providing professional support, and to use the sources in an organized way for the successful transition of parents from the stress of their children surgery.

Calculation of Collective Variable-based PMF by Combining WHAM with Umbrella Sampling

International Nuclear Information System (INIS)

Xu Wei-Xin; Li Yang; Zhang, John Z. H.

2012-01-01

Potential of mean force (PMF) with respect to localized reaction coordinates (RCs) such as distance is often applied to evaluate the free energy profile along the reaction pathway for complex molecular systems. However, calculation of PMF as a function of global RCs is still a challenging and important problem in computational biology. We examine the combined use of the weighted histogram analysis method and the umbrella sampling method for the calculation of PMF as a function of a global RC from the coarse-grained Langevin dynamics simulations for a model protein. The method yields the folding free energy profile projected onto a global RC, which is in accord with benchmark results. With this method rare global events would be sufficiently sampled because the biased potential can be used for restricting the global conformation to specific regions during free energy calculations. The strategy presented can also be utilized in calculating the global intra- and intermolecular PMF at more detailed levels. (cross-disciplinary physics and related areas of science and technology)

Analysis of the Umbrella Roof for lifting

International Nuclear Information System (INIS)

Shaaban, A.

1983-01-01

In addition to supporting the dead loads and the operational loads, the Umbrella Roof (UR) has two major functions to which it was designed. First is to allow access for repair and removal of any of the TF coils, the upper PF coils and the Vacuum Vessel sections; and second, is to reproduce the exact positioning of the upper PF coils every time the UR is placed over the Tokamac. To provide these functions, the UR is designed to be lifted as one integrated structure to which the upper PF coils are attached. In order to ensure precise positioning of the UR, a redundant system of 13 guide pins were provided on the bottom of the radial beams, and four shear lugs were provided atop the central column. Mating reciprocals with very close tolerance for the guide pins were provided in the tops of the 13 peripheral columns. To meet close tolerances and to accommodate such high redundancy in match points, accurate analysis was necessary by which the center of gravity of the UR can be located and the deflection of all match points can be computed. Also stress analysis of the members of the UR was necessary because when the UR is lifted it is denied the midpoint support over the center column; and also the beams of the UR are not interconnected by moment-capable joints, thus if provisions are not made to support every radial beam, those which are not supported would yield and collapse. In this paper, the lifting schemes proposed for the UR are discussed and the results of the analysis performed for the elected scheme are presented. Also presented is a unique application of the NASTRAN code by which the center of gravity of the UR was located by allowing a refined model of the UR to swing until it came to rest under an arbitrary lift point

Efficient parallel implementations of QM/MM-REMD (quantum mechanical/molecular mechanics-replica-exchange MD) and umbrella sampling: isomerization of H2O2 in aqueous solution.

Science.gov (United States)

Fedorov, Dmitri G; Sugita, Yuji; Choi, Cheol Ho

2013-07-03

An efficient parallel implementation of QM/MM-based replica-exchange molecular dynamics (REMD) as well as umbrella samplings techniques was proposed by adopting the generalized distributed data interface (GDDI). Parallelization speed-up of 40.5 on 48 cores was achieved, making our QM/MM-MD engine a robust tool for studying complex chemical dynamics in solution. They were comparatively used to study the torsional isomerization of hydrogen peroxide in aqueous solution. All results by QM/MM-REMD and QM/MM umbrella sampling techniques yielded nearly identical potentials of mean force (PMFs) regardless of the particular QM theories for solute, showing that the overall dynamics are mainly determined by solvation. Although the entropic penalty of solvent rearrangements exists in cisoid conformers, it was found that both strong intermolecular hydrogen bonding and dipole-dipole interactions preferentially stabilize them in solution, reducing the torsional free-energy barrier at 0° by about 3 kcal/mol as compared to that in gas phase.

Ideology and Orientalism in American and Cuban news media : Representation of the Chinese government in foreign media during the Umbrella Revolution

OpenAIRE

Aleñá Naval, Gerard

2017-01-01

This study aims to examine the representation of the Chinese government in foreign media during the Umbrella Revolution along 2014. Hence, this paper analyzes The New York Times and Granma by using Critical Discourse Analysis along with Multimodal Critical Discourse Analysis in order to reveal underlying ideology and Orientalism in their news discourse. Thus, this study aims to understand how influenced is their representation of the Chinese government by the ideology of their countries. In t...

General Principles and Convention on Contracts for the International Sale of Goods (CISG – Uniformity under an Interpretation Umbrella?

Directory of Open Access Journals (Sweden)

Laura Lassila

2017-01-01

Full Text Available Globalization and digitalization of international sales creates needs to harmonize rules of international commercial contracts. The question is whether the harmonization should be done by binding rules or using soft law tools or through digitalization. In this article I argue on favor of harmonization through international contracts law rules’ international interpretation.The international interpretation principles used in this article are found from on Art. 7(1 of the Convention on Contracts for the International Sale of Goods (CISG which sets three interpretation rules: international character; promoting uniformity; and observance of good faith in international trade. These principles are not only principles of the CISG, but also principles commonly recognized in international commercial practice and also in domestic contract rules. I argue that by adopting an international interpretation umbrella – the meta-principle of international interpretation, cross-border contracts could be interpreted under the same principle no matter applicable substantial law. The meta-principle functions as an interpretation umbrella covering general principles and Articles of the CISG, general principles of international commercial contracts, Lex Mercatoria, and cross-border contract provision under national law.The outcomes points out that arbitral tribunals have interpreted general principles of the CISG and Lex Mercatoria in various ways. General principles and their application in case law is analyzed in connection with the Civil Code of the Russian Federation. Tribunals found that general principles of the CISG are applicable even if the CISG is not. It follows Art.’s 7(2 logic to promote international standard to cross-border contracts where the closes connection is international commercial practice rather than any national jurisdiction.

Coffee consumption and health: umbrella review of meta-analyses of multiple health outcomes.

Science.gov (United States)

Poole, Robin; Kennedy, Oliver J; Roderick, Paul; Fallowfield, Jonathan A; Hayes, Peter C; Parkes, Julie

2017-11-22

Objectives  To evaluate the existing evidence for associations between coffee consumption and multiple health outcomes. Design  Umbrella review of the evidence across meta-analyses of observational and interventional studies of coffee consumption and any health outcome. Data sources  PubMed, Embase, CINAHL, Cochrane Database of Systematic Reviews, and screening of references. Eligibility criteria for selecting studies  Meta-analyses of both observational and interventional studies that examined the associations between coffee consumption and any health outcome in any adult population in all countries and all settings. Studies of genetic polymorphisms for coffee metabolism were excluded. Results  The umbrella review identified 201 meta-analyses of observational research with 67 unique health outcomes and 17 meta-analyses of interventional research with nine unique outcomes. Coffee consumption was more often associated with benefit than harm for a range of health outcomes across exposures including high versus low, any versus none, and one extra cup a day. There was evidence of a non-linear association between consumption and some outcomes, with summary estimates indicating largest relative risk reduction at intakes of three to four cups a day versus none, including all cause mortality (relative risk 0.83 (95% confidence interval 0.79 to 0.88), cardiovascular mortality (0.81, 0.72 to 0.90), and cardiovascular disease (0.85, 0.80 to 0.90). High versus low consumption was associated with an 18% lower risk of incident cancer (0.82, 0.74 to 0.89). Consumption was also associated with a lower risk of several specific cancers and neurological, metabolic, and liver conditions. Harmful associations were largely nullified by adequate adjustment for smoking, except in pregnancy, where high versus low/no consumption was associated with low birth weight (odds ratio 1.31, 95% confidence interval 1.03 to 1.67), preterm birth in the first (1.22, 1.00 to 1.49) and second (1

Dose-response relationship between cigarette smoking and site-specific cancer risk: protocol for a systematic review with an original design combining umbrella and traditional reviews.

Science.gov (United States)

Lugo, Alessandra; Bosetti, Cristina; Peveri, Giulia; Rota, Matteo; Bagnardi, Vincenzo; Gallus, Silvano

2017-11-01

Only a limited number of meta-analyses providing risk curve functions of dose-response relationships between various smoking-related variables and cancer-specific risk are available. To identify all relevant original publications on the issue, we will conduct a series of comprehensive systematic reviews based on three subsequent literature searches: (1) an umbrella review, to identify meta-analyses, pooled analyses and systematic reviews published before 28 April 2017 on the association between cigarette smoking and the risk of 28 (namely all) malignant neoplasms; (2) for each cancer site, an updated review of original publications on the association between cigarette smoking and cancer risk, starting from the last available comprehensive review identified through the umbrella review; and (3) a review of all original articles on the association between cigarette smoking and site-specific cancer risk included in the publications identified through the umbrella review and the updated reviews. The primary outcomes of interest will be (1) the excess incidence/mortality of various cancers for smokers compared with never smokers; and (2) the dose-response curves describing the association between smoking intensity, duration and time since stopping and incidence/mortality for various cancers. For each cancer site, we will perform a meta-analysis by pooling study-specific estimates for smoking status. We will also estimate the dose-response curves for other smoking-related variables through random-effects meta-regression models based on a non-linear dose-response relationship framework. Ethics approval is not required for this study. Main results will be published in peer-reviewed journals and will also be included in a publicly available website. We will provide therefore the most complete and updated estimates on the association between various measures of cigarette smoking and site-specific cancer risk. This will allow us to obtain precise estimates on the cancer burden

Umbrella project for Bangladesh: strengthening NGO capacity and linkages to improve reproductive health service and information. RAS/98/P55.

Science.gov (United States)

1999-06-01

In Bangladesh, the UN Population Fund is working to strengthen nongovernmental organization (NGO) capacity and linkages to improve reproductive health services and information. Specifically, the aim is to strengthen the technical and human resource capacity of participating NGOs and the functional linkages between national NGOs and relevant government agencies to help harmonize and standardize the delivery of reproductive health information and services. This umbrella project collaborates with RHI-participating NGOs in a policy paper on adolescent reproductive health, and will maintain contact with the regional dimension project to collaborate its activities. Programs implemented by partner NGOs are being reviewed and monitored, and linkages among national NGOs and government agencies are being developed. The main activities of the project are enumerated.

Simulation Modelling in Healthcare: An Umbrella Review of Systematic Literature Reviews.

Science.gov (United States)

Salleh, Syed; Thokala, Praveen; Brennan, Alan; Hughes, Ruby; Booth, Andrew

2017-09-01

Numerous studies examine simulation modelling in healthcare. These studies present a bewildering array of simulation techniques and applications, making it challenging to characterise the literature. The aim of this paper is to provide an overview of the level of activity of simulation modelling in healthcare and the key themes. We performed an umbrella review of systematic literature reviews of simulation modelling in healthcare. Searches were conducted of academic databases (JSTOR, Scopus, PubMed, IEEE, SAGE, ACM, Wiley Online Library, ScienceDirect) and grey literature sources, enhanced by citation searches. The articles were included if they performed a systematic review of simulation modelling techniques in healthcare. After quality assessment of all included articles, data were extracted on numbers of studies included in each review, types of applications, techniques used for simulation modelling, data sources and simulation software. The search strategy yielded a total of 117 potential articles. Following sifting, 37 heterogeneous reviews were included. Most reviews achieved moderate quality rating on a modified AMSTAR (A Measurement Tool used to Assess systematic Reviews) checklist. All the review articles described the types of applications used for simulation modelling; 15 reviews described techniques used for simulation modelling; three reviews described data sources used for simulation modelling; and six reviews described software used for simulation modelling. The remaining reviews either did not report or did not provide enough detail for the data to be extracted. Simulation modelling techniques have been used for a wide range of applications in healthcare, with a variety of software tools and data sources. The number of reviews published in recent years suggest an increased interest in simulation modelling in healthcare.

Double hard scattering without double counting

Energy Technology Data Exchange (ETDEWEB)

Diehl, Markus [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Gaunt, Jonathan R. [VU Univ. Amsterdam (Netherlands). NIKHEF Theory Group; Schoenwald, Kay [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany)

2017-02-15

Double parton scattering in proton-proton collisions includes kinematic regions in which two partons inside a proton originate from the perturbative splitting of a single parton. This leads to a double counting problem between single and double hard scattering. We present a solution to this problem, which allows for the definition of double parton distributions as operator matrix elements in a proton, and which can be used at higher orders in perturbation theory. We show how the evaluation of double hard scattering in this framework can provide a rough estimate for the size of the higher-order contributions to single hard scattering that are affected by double counting. In a numeric study, we identify situations in which these higher-order contributions must be explicitly calculated and included if one wants to attain an accuracy at which double hard scattering becomes relevant, and other situations where such contributions may be neglected.

Double hard scattering without double counting

International Nuclear Information System (INIS)

Diehl, Markus; Gaunt, Jonathan R.

2017-02-01

Double parton scattering in proton-proton collisions includes kinematic regions in which two partons inside a proton originate from the perturbative splitting of a single parton. This leads to a double counting problem between single and double hard scattering. We present a solution to this problem, which allows for the definition of double parton distributions as operator matrix elements in a proton, and which can be used at higher orders in perturbation theory. We show how the evaluation of double hard scattering in this framework can provide a rough estimate for the size of the higher-order contributions to single hard scattering that are affected by double counting. In a numeric study, we identify situations in which these higher-order contributions must be explicitly calculated and included if one wants to attain an accuracy at which double hard scattering becomes relevant, and other situations where such contributions may be neglected.

Exercise for adults with fibromyalgia: an umbrella systematic review with synthesis of best evidence.

Science.gov (United States)

Bidonde, Julia; Busch, Angela Jean; Bath, Brenna; Milosavljevic, Stephan

2014-01-01

The objective of this umbrella systematic review was to identify, evaluate, and synthesize systematic reviews of physical activity interventions for adults with fibromyalgia (FM) focussing on four outcomes: pain, multidimensional function (wellness or quality of life), physical function (self-reported physical function or measured physical fitness) and adverse effects. A further objective was to link these outcomes with details of the interventions so as to guide and shape future practice and research. Electronic databases including Medline, EMBASE, CINAHL, AMED, the Cochrane Library, and DARE, were searched for the January 1(st) 2007 to March 31(st) 2013 period. Nine systematic reviews (60 RCTs with 3816 participants) were included. Meta-analysis was not conducted due to the heterogeneity of the sample. We found positive results of diverse exercise interventions on pain, multidimensional function, and self-reported physical function, and no supporting evidence for new (to FM) interventions (i.e., qigong, tai chi). There were no serious adverse effects reported. The variability of the interventions in the reviews prevented us from answering important clinical questions to guide practical decisions about optimal modes or dosages (i.e., frequency, intensity, duration). Finally, the number of review articles is proliferating, leading researchers and reviewers to consider the rigor and quality of the information being reviewed. As well, consumers of these reviews (i.e., clinicians, individuals with FM) should not rely on them without careful consideration.

An umbrella review of meta-analyses of interventions to improve maternal outcomes for teen mothers.

Science.gov (United States)

SmithBattle, Lee; Loman, Deborah G; Chantamit-O-Pas, Chutima; Schneider, Joanne Kraenzle

2017-08-01

The purpose of this study was to perform an umbrella review of meta-analyses of intervention studies designed to improve outcomes of pregnant or parenting teenagers. An extensive search retrieved nine reports which provided 21 meta-analyses analyses. Data were extracted by two reviewers. Methodological quality was assessed using the AMSTAR Instrument. Most effect sizes were small but high quality studies showed significant outcomes for reduced low birth weight (RR = 0.60), repeat pregnancies/births (OR = 0.47-0.62), maternal education (OR = 1.21-1.83), and maternal employment (OR = 1.26). Several parenting outcomes (parent-child teaching interaction post-intervention [SMD = -0.91] and at follow-up [SMD = -1.07], and parent-child relationship post-intervention [SMD = -0.71] and at follow-up [SMD = -0.90]) were significant, but sample sizes were very small. Many reports did not include moderator analyses. Behavioral interventions offer limited resources and occur too late to mitigate the educational and social disparities that precede teen pregnancy. Future intervention research and policies that redress the social determinants of early childbearing are recommended. Copyright © 2017 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Ac-induced disruption of the doubleDs structure in tomato

NARCIS (Netherlands)

Rommens, Caius M.T.; Biezen, Erik A. van der; Ouwerkerk, Pieter B.F.; Nijkamp, H. John J.; Hille, Jacques

1991-01-01

The maize doubleDs element is stably maintained in the tomato genome. Upon the subsequent introduction of Ac into a plant containing doubleDs, disruption of the doubleDs structure and DNA rearrangements at the site of the doubleDs element were observed. No indications were obtained for excision of

Sea Ice, Clouds, Sunlight, and Albedo: The Umbrella Versus the Blanket

Science.gov (United States)

Perovich, D. K.

2017-12-01

The Arctic sea ice cover has undergone a major decline in recent years, with reductions in ice extent, ice thickness, and ice age. Understanding the feedbacks and forcing driving these changes is critical in improving predictions. The surface radiation budget plays a central role in summer ice melt and is governed by clouds and surface albedo. Clouds act as an umbrella reducing the downwelling shortwave, but also serve as a blanket increasing the downwelling longwave, with the surface albedo also determining the net balance. Using field observations from the SHEBA program, pairs of clear and cloudy days were selected for each month from May through September and the net radiation flux was calculated for different surface conditions and albedos. To explore the impact of albedo we calculated a break even albedo, where the net radiation for cloudy skies is the same as clear skies. For albedos larger than the break-even value the net radiation flux is smaller under clear skies compared to cloudy skies. Break-even albedos ranged from 0.30 in September to 0.58 in July. For snow covered or bare ice, clear skies always resulted in less radiative heat input. In contrast, leads always had, and ponds usually had, more radiative heat input under clear skies than cloudy skies. Snow covered ice had a net radiation flux that was negative or near zero under clear skies resulting in radiative cooling. We combined the albedo of individual ice types with the area of those ice types to calculate albedos averaged over a 50 km x 50 km area. The July case had the smallest areally averaged albedo of 0.50. This was less than the breakeven albedo, so cloudy skies had a smaller net radiation flux than clear skies. For the cases from the other four months, the areally averaged albedo was greater than the break-even albedo. The areally averaged net radiation flux was negative under clear skies for the May and September cases.

Health education for patients with acute coronary syndrome and type 2 diabetes mellitus: an umbrella review of systematic reviews and meta-analyses.

Science.gov (United States)

Liu, Xian-Liang; Shi, Yan; Willis, Karen; Wu, Chiung-Jung Jo; Johnson, Maree

2017-10-16

This umbrella review aimed to identify the current evidence on health education-related interventions for patients with acute coronary syndrome (ACS) or type two diabetes mellitus (T2DM); identify the educational content, delivery methods, intensity, duration and setting required. The purpose was to provide recommendations for educational interventions for high-risk patients with both ACS and T2DM. Umbrella review of systematic reviews and meta-analyses. Inpatient and postdischarge settings. Patients with ACS and T2DM. CINAHL, Cochrane Library, Joanna Briggs Institute, Journals@Ovid, EMBase, Medline, PubMed and Web of Science databases from January 2000 through May 2016. Clinical outcomes (such as glycated haemoglobin), behavioural outcomes (such as smoking), psychosocial outcomes (such as anxiety) and medical service use. Fifty-one eligible reviews (15 for ACS and 36 for T2DM) consisting of 1324 relevant studies involving 2 88 057 patients (15 papers did not provide the total sample); 30 (58.8%) reviews were rated as high quality. Nurses only and multidisciplinary teams were the most frequent professionals to provide education, and most educational interventions were delivered postdischarge. Face-to-face sessions were the most common delivery formats, and many education sessions were also delivered by telephone or via web contact. The frequency of educational sessions was weekly or monthly, and an average of 3.7 topics was covered per education session. Psychoeducational interventions were generally effective at reducing smoking and admissions for patients with ACS. Culturally appropriate health education, self-management educational interventions, group medical visits and psychoeducational interventions were generally effective for patients with T2DM. Results indicate that there is a body of current evidence about the efficacy of health education, its content and delivery methods for patients with ACS or T2DM. These results provide recommendations about the

Exercise improves depressive symptoms in older adults: An umbrella review of systematic reviews and meta-analyses.

Science.gov (United States)

Catalan-Matamoros, Daniel; Gomez-Conesa, Antonia; Stubbs, Brendon; Vancampfort, Davy

2016-10-30

Late-life depression is a growing public health concern. Exercise may be of added value but the literature remains equivocal. We conducted a systematic overview of meta-analyses and an exploratory pooled analysis of previous meta-analyses to determine the effect of exercise on depression in older adults. Two independent researchers searched Pubmed, CINAHL, Cochrane Plus, PsycArticles, and PsycInfo for meta-analyses on exercise in late-life depression. Methodological quality was assessed using the Assessment of Multiple Systematic Reviews (AMSTAR) Instrument. We pooled effect sizes from previous meta-analyses of randomized controlled trials to determine the effect of exercise on depression in older adults. The systematic review yielded 3 meta-analyses. In total, 16 unique cohorts of 1487 participants were included. The quality of the three included meta-analyses was considered as "moderate" according to AMSTAR scores. No serious adverse events were reported. Compared to controls (n=583), those exercising (n=541) significantly reduced depressive symptoms. Our umbrella review indicates that exercise is safe and efficacious in reducing depressive symptoms in older people. Since exercise has many other known health benefits, it should be considered as a core intervention in the multidisciplinary treatment of older adults experiencing depression. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Predicting risk and outcomes for frail older adults: an umbrella review of frailty screening tools

Science.gov (United States)

Apóstolo, João; Cooke, Richard; Bobrowicz-Campos, Elzbieta; Santana, Silvina; Marcucci, Maura; Cano, Antonio; Vollenbroek-Hutten, Miriam; Germini, Federico; Holland, Carol

2017-01-01

EXECUTIVE SUMMARY Background A scoping search identified systematic reviews on diagnostic accuracy and predictive ability of frailty measures in older adults. In most cases, research was confined to specific assessment measures related to a specific clinical model. Objectives To summarize the best available evidence from systematic reviews in relation to reliability, validity, diagnostic accuracy and predictive ability of frailty measures in older adults. Inclusion criteria Population Older adults aged 60 years or older recruited from community, primary care, long-term residential care and hospitals. Index test Available frailty measures in older adults. Reference test Cardiovascular Health Study phenotype model, the Canadian Study of Health and Aging cumulative deficit model, Comprehensive Geriatric Assessment or other reference tests. Diagnosis of interest Frailty defined as an age-related state of decreased physiological reserves characterized by an increased risk of poor clinical outcomes. Types of studies Quantitative systematic reviews. Search strategy A three-step search strategy was utilized to find systematic reviews, available in English, published between January 2001 and October 2015. Methodological quality Assessed by two independent reviewers using the Joanna Briggs Institute critical appraisal checklist for systematic reviews and research synthesis. Data extraction Two independent reviewers extracted data using the standardized data extraction tool designed for umbrella reviews. Data synthesis Data were only presented in a narrative form due to the heterogeneity of included reviews. Results Five reviews with a total of 227,381 participants were included in this umbrella review. Two reviews focused on reliability, validity and diagnostic accuracy; two examined predictive ability for adverse health outcomes; and one investigated validity, diagnostic accuracy and predictive ability. In total, 26 questionnaires and brief assessments and eight frailty

Double-double effect and coordination number

International Nuclear Information System (INIS)

Mioduski, T.

1992-01-01

The original method of interpretation together with its theoretical foundations is developed, making it possible to use location and direction of the double-double (tetrad) effect within the Ln and An series to determine the coordination number (CN) complexes of the f-block elements. The method is applied for potentiometric and radiometric equilibrium studies. It has been pointed and that the decisive factor for the direction of the double-double effect in the case of the Gibbs energy variations is a difference in the CN of the f-element ion between the reaction product complex and that for the reaction substrate the ''regular'' effect for a given tetrad is accompanied by decrease in the CN while the ''reverse'' effect by increase in the CN. (author). 122 refs, 5 tabs, 8 figs

Obesity and gynaecological and obstetric conditions: umbrella review of the literature.

Science.gov (United States)

Kalliala, Ilkka; Markozannes, Georgios; Gunter, Marc J; Paraskevaidis, Evangelos; Gabra, Hani; Mitra, Anita; Terzidou, Vasso; Bennett, Phillip; Martin-Hirsch, Pierre; Tsilidis, Konstantinos K; Kyrgiou, Maria

2017-10-26

Objective  To study the strength and validity of associations between adiposity and risk of any type of obstetric or gynaecological conditions. Design  An umbrella review of meta-analyses. Data sources  PubMed, Cochrane database of systematic reviews, manual screening of references for systematic reviews or meta-analyses of observational and interventional studies evaluating the association between adiposity and risk of any obstetrical or gynaecological outcome. Main outcomes  Meta-analyses of cohort studies on associations between indices of adiposity and obstetric and gynaecological outcomes. Data synthesis  Evidence from observational studies was graded into strong, highly suggestive, suggestive, or weak based on the significance of the random effects summary estimate and the largest study in the included meta-analysis, the number of cases, heterogeneity between studies, 95% prediction intervals, small study effects, excess significance bias, and sensitivity analysis with credibility ceilings. Interventional meta-analyses were assessed separately. Results  156 meta-analyses of observational studies were included, investigating associations between adiposity and risk of 84 obstetric or gynaecological outcomes. Of the 144 meta-analyses that included cohort studies, only 11 (8%) had strong evidence for eight outcomes: adiposity was associated with a higher risk of endometrial cancer, ovarian cancer, antenatal depression, total and emergency caesarean section, pre-eclampsia, fetal macrosomia, and low Apgar score. The summary effect estimates ranged from 1.21 (95% confidence interval 1.13 to 1.29) for an association between a 0.1 unit increase in waist to hip ratio and risk endometrial cancer up to 4.14 (3.61 to 4.75) for risk of pre-eclampsia for BMI >35 compared with <25. Only three out of these eight outcomes were also assessed in meta-analyses of trials evaluating weight loss interventions. These interventions significantly reduced the risk of caesarean

Double Charge Exchange Reactions and Double Beta Decay

Science.gov (United States)

Auerbach, N.

2018-05-01

The subject of this presentation is at the forefront of nuclear physics, namely double beta decay. In particular one is most interested in the neutrinoless process of double beta decay, when the decay proceeds without the emission of two neutrinos. The observation of such decay would mean that the lepton conservation symmetry is violated and that the neutrinos are of Majorana type, meaning that they are their own anti-particles. The life time of this process has two unknowns, the mass of the neutrino and the nuclear matrix element. Determining the nuclear matrix element and knowing the cross-section well will set limits on the neutrino mass. There is a concentrated effort among the nuclear physics community to calculate this matrix element. Usually these matrix elements are a very small part of the total strength of the transition operators involved in the process. There is no simple way to “calibrate” the nuclear double beta decay matrix element. The double beta decay is a double charge exchange process, therefore it is proposed that double charge exchange reactions using ion projectiles on nuclei that are candidates for double beta decay, will provide additional necessary information about the nuclear matrix elements.

Concordance of sleep and pain outcomes of diverse interventions: an umbrella review.

Directory of Open Access Journals (Sweden)

Anthony G Doufas

Full Text Available BACKGROUND/OBJECTIVE: Pain influences sleep and vice versa. We performed an umbrella review of meta-analyses on treatments for diverse conditions in order to examine whether diverse medical treatments for different conditions have similar or divergent effects on pain and sleep. METHODS: We searched published systematic reviews with meta-analyses in the Cochrane Database of Systematic Reviews until October 20, 2011. We identified randomized trials (or meta-analyses thereof, when >1 trial was available where both pain and sleep outcomes were examined. Pain outcomes were categorized as headache, musculoskeletal, abdominal, pelvic, generic or other pain. Sleep outcomes included insomnia, sleep disruption, and sleep disturbance. We estimated odds ratios for all outcomes and evaluated the concordance in the direction of effects between sleep and various types of pain and the correlation of treatment effects between sleep and pain outcomes. RESULTS: 151 comparisons with 385 different trials met our eligibility criteria. 96 comparisons had concordant direction of effects between each pain outcome and sleep, while in 55 the effect estimates were in opposite directions (P<0.0001. In the 20 comparisons with largest amount of evidence, the experimental drug always had worse sleep outcomes and tended to have worse pain outcomes in 17/20 cases. For headache and musculoskeletal pain, 69 comparisons showed concordant direction of effects with sleep outcomes and 36 showed discordant direction (P<0.0001. For the other 4 pain types there were overall 27 vs. 19 pairs with concordant vs. discordant direction of effects (P = 0.095. There was a weak correlation of the treatment effect sizes for sleep vs. headache/musculoskeletal pain (r = 0.17, P = 0.092. CONCLUSIONS: Medical interventions tend to have effects in the same direction for pain and sleep outcomes, but exceptions occur. Concordance is primarily seen for sleep and headache or musculoskeletal

SWOT ANALYSIS MICRO SMALL MEDIUM ENTREPRISE (MSME GEULIS CRAFT UMBRELLA TO SUCCESS IN LOCAL ECONOMIC DEVELOPMENT RESOURCES DISTRICT TASIKMALAYA

Directory of Open Access Journals (Sweden)

K. Dianta A. Sebayang

2012-03-01

Full Text Available Development of local economic resources, a new trend in the effort to increase the income of the community and the region. Local factors that determine both in terms of natural resources (raw materials and human resources (labor. This paper attempts to present how small and medium enterprises "Kerajinan Payung Geulis" try to improve economic development based on the development of local economic resources in Tasikmalaya. This study aims to illustrate the potential of entrepreneurs that include the competence and commitment of entrepreneurs in small business business, and to illustrate the strength of business / competitive position, business profile and entrepreneur influenced by environmental condition of external and internal environment, seen from the positive and negative side. The research was conducted on umbrella industry of handicraft business in Tasikmalaya. The method used in this research is descriptive analysis by using SWOT analysis. The results show many problems encountered and very complex, such as: low quality of human resources, limited business capital, low access to markets, access to financial institutions / banks are absent, administrative procedures ignorance, sustainability and limited capacity production; Coupled with the business climate is not conducive to the development of SMEs and entrepreneurship.

Interventions to improve physical activity among socioeconomically disadvantaged groups: an umbrella review.

Science.gov (United States)

Craike, Melinda; Wiesner, Glen; Hilland, Toni A; Bengoechea, Enrique Garcia

2018-05-15

People from socioeconomically disadvantaged population groups are less likely to be physically active and more likely to experience adverse health outcomes than those who are less disadvantaged. In this umbrella review we examined across all age groups, (1) the effectiveness of interventions to improve physical activity among socioeconomically disadvantaged groups, (2) the characteristics of effective interventions, and (3) directions for future research. PubMed/MEDLINE and Scopus were searched up to May 2017 to identify systematic reviews reporting physical activity interventions in socioeconomically disadvantaged populations or sub-groups. Two authors independently conducted study screening and selection, data extraction (one author, with data checked by two others) and assessment of methodological quality using the 'Assessment of Multiple Systematic Reviews' scale. Results were synthesized narratively. Seventeen reviews met our inclusion criteria, with only 5 (30%) reviews being assessed as high quality. Seven (41%) reviews focused on obesity prevention and an additional four focused on multiple behavioural outcomes. For pre school children, parent-focused, group-based interventions were effective in improving physical activity. For children, school-based interventions and policies were effective; few studies focused on adolescents and those that did were generally not effective; for adults, there was mixed evidence of effectiveness but characteristics such as group-based interventions and those that focused on physical activity only were associated with effectiveness. Few studies focused on older adults. Across all ages, interventions that were more intensive tended to be more effective. Most studies reported short-term, rather than longer-term, outcomes and common methodological limitations included high probability of selection bias, low response rates, and high attrition. Interventions can be successful at improving physical activity among children from

Short communication. Tomography as a method to study umbrella pine (Pinus pinea) cones and nuts

Energy Technology Data Exchange (ETDEWEB)

Nunes, A.; Pereira, H.; Tomé, M.; Silva, J.; Fontes, L.

2016-07-01

Aim of the study: Umbrella or stone pine (Pinus pinea) nuts are one of the most valuable and expensive non-wood forest products in Portugal. The increasing market and landowner's interest resulted on a high expansion of plantation areas. This study tests the feasibility of using tomography to characterize pine cones and nuts. Area of study: The research was carried out in pine stand, with nine years, grafted in 2011, on Herdade of Machoqueira do Grou, near Coruche, in Portugal’s central area. Material and Methods: Starting in June 2015, ten pine cones in their final stage of development, were randomly monthly collected, and evaluated with tomography equipment commonly used in clinical medicine, according to Protocol Abdomen Mean. A sequence of images corresponding to 1mm-spaced cross-sections were obtained and reconstructed to produce a 3D model. The segmented images were worked using free image processing software, like RadiAnt Dicom Viewer, Data Viewer and Ctvox. Main results: The cone’s structures were clearly visible on the images, and it was possible to easily identify empty pine nuts. Although expensive, tomography is an easy and quick application technique that allows to assess the internal structures, through the contrast of materials densities, allowing to estimate pine nut’s size and empty nut’s proportion. By analysis of ninety images, it was obtained, an estimated mean value of 25.5 % empty nuts. Research highlights: Results showed the potential of tomography as a screening tool to be used in industry and research areas, for analysis and diagnostic of stone pine cone’s structures. (Author)

US/FRG umbrella agreement for cooperation in GCR Development. Fuel, fission products, and graphite subprogram. Quarterly status report, July 1, 1982-September 30, 1982

International Nuclear Information System (INIS)

Turner, R.F.

1982-10-01

This report describes the status of the cooperative work being performed in the Fuel, Fission Product, and Graphite Subprogram under the HTR-Implementing Agreement of the United States/Federal Republic of Germany Umbrella Agreement for Cooperation in GCR Development. The status is described relative to the commitments in the Subprogram Plan for Fuel, Fission Products, and Graphite, Revision 5, April 1982. The work described was performed during the period July 1, 1982 through September 30, 1982 in the HTGR Base Technology Program at Oak Ridge National Laboratory, the HTGR Fuel and Plant Technology Programs at General Atomic Company (GA), and the Project HTR-Brennstoffkreislauf of the Entwicklungsgemeinschaft HTR at KFA Julich, HRB Mannheim, HOBEG Hanau, and SIGRI Meitingen. The requirement for and format of this quarterly status report are specified in the HTR Implementing Agreement procedures for cooperation. Responsibility for preparation of the quarterly report alternates between GA and KFA

The initial giant umbrella cloud of the May 18th, 1980, explosive eruption of Mount St. Helens

Science.gov (United States)

Sparks, R.S.J.; Moore, J.G.; Rice, C.J.

1986-01-01

The initial eruption column of May 18th, 1980 reached nearly 30 km altitude and released 1017 joules of thermal energy into the atmosphere in only a few minutes. Ascent of the cloud resulted in forced intrusion of a giant umbrella-shaped cloud between altitudes of 10 and 20 km at radial horizontal velocities initially in excess of 50 m/s. The mushroom cloud expanded 15 km upwind, forming a stagnation point where the radial expansion velocity and wind velocity were equal. The cloud was initiated when the pyroclastic blast flow became buoyant. The flow reduced its density as it moved away from the volcano by decompression, by sedimentation, and by mixing with and heating the surrounding air. Observations indicate that much of the flow, covering an area of 600 km2, became buoyant within 1.5 minutes and abruptly ascended to form the giant cloud. Calculations are presented for the amount of air that must have been entrained into the flow to make it buoyant. Assuming an initial temperature of 450??C and a magmatic origin for the explosion, these calculations indicate that the flow became buoyant when its temperature was approximately 150??C and the flow consisted of a mixture of 3.25 ?? 1011 kg of pyroclasts and 5.0 ?? 1011 kg of air. If sedimentation is considered, these figures reduce to 1.1 ?? 1011 kg of pyroclasts and 1.0 ?? 1011 kg of air. ?? 1986.

Scientists and Educators in Sync: Exploring the Strengths of Each through a Collaborative Educational "Umbrella" on Space Weather

Science.gov (United States)

Cobabe-Ammann, E. A.; Singer, H. J.

2003-12-01

Scientists and educators have much to offer formal and informal science education forums (and each other) when brought together in balanced collaboration. New educational opportunities from NASA and NSF have made it easier to develop these collaborations, effectively allowing for the establishment of educational "umbrellas" whereby several separately funded programs focused on a single theme are overseen by a single working group. Here, we explore one such collaboration on space weather developed by CU's Laboratory for Atmospheric and Space Physics, in collaboration with NOAA's Space Environment Center, the Fiske Planetarium, the Space Science Institute and teachers from local school districts. The goal of the collaboration is to develop a new planetarium show, associated curricula and teacher workshops and guidebooks, as well as distance learning programming through the NASA Center for Distance Learning. One hallmark of this collaboration is the recognition that both scientists and educators bring important research-based perspectives to the table - Scientists are primarily responsible for the scientific integrity of the programming; Educators offer effective (tested) educational models for implementing student and teacher experiences. Both bring creativity, ingenuity and innovation to this dynamic environment. Sustainability is enhanced by integrating components and activities into a cogent whole, and efforts are perceived as even more worthwhile since most aspects of this program will be available for national distribution over the next several years.

Family-related predictors of body weight and weight-related behaviours among children and adolescents: a systematic umbrella review.

Science.gov (United States)

Cislak, A; Safron, M; Pratt, M; Gaspar, T; Luszczynska, A

2012-05-01

This umbrella review analysed the relationships between family variables and child/adolescent body weight, diet and physical activity. In line with theories of health behaviour change, it was assumed that behaviour-specific family variables (i.e. beliefs, perceptions and practices referring to food intake or physical activity) would have stronger support than more general family variables (i.e. socio-economic status or general parental practices). Data obtained from 18 systematic reviews (examining 375 quantitative studies) were analysed. Reviews of experimental trials generally supported the effectiveness of reward/positive reinforcement parental strategies, parental involvement in treatment or prevention programmes, and cognitive-behavioural treatment in reducing child/adolescent body mass and/or obesity. Results across reviews of correlational studies indicated that healthy nutrition of children/adolescents was related to only one parental practice (parental monitoring), but was associated with several behaviour-specific family variables (e.g. a lack of restrictive control over food choices, high intake of healthy foods and low intake of unhealthy foods by parents and siblings, low pressure to consume foods). With regard to adolescent physical activity, stronger support was also found for behaviour-specific variables (e.g. physical activity of siblings), and for certain socio-economic variables (e.g. parental education). Child and adolescent obesity prevention programmes should account for behaviour-specific family variables. © 2011 Blackwell Publishing Ltd.

Observing Double Stars

Science.gov (United States)

Genet, Russell M.; Fulton, B. J.; Bianco, Federica B.; Martinez, John; Baxter, John; Brewer, Mark; Carro, Joseph; Collins, Sarah; Estrada, Chris; Johnson, Jolyon; Salam, Akash; Wallen, Vera; Warren, Naomi; Smith, Thomas C.; Armstrong, James D.; McGaughey, Steve; Pye, John; Mohanan, Kakkala; Church, Rebecca

2012-05-01

Double stars have been systematically observed since William Herschel initiated his program in 1779. In 1803 he reported that, to his surprise, many of the systems he had been observing for a quarter century were gravitationally bound binary stars. In 1830 the first binary orbital solution was obtained, leading eventually to the determination of stellar masses. Double star observations have been a prolific field, with observations and discoveries - often made by students and amateurs - routinely published in a number of specialized journals such as the Journal of Double Star Observations. All published double star observations from Herschel's to the present have been incorporated in the Washington Double Star Catalog. In addition to reviewing the history of visual double stars, we discuss four observational technologies and illustrate these with our own observational results from both California and Hawaii on telescopes ranging from small SCTs to the 2-meter Faulkes Telescope North on Haleakala. Two of these technologies are visual observations aimed primarily at published "hands-on" student science education, and CCD observations of both bright and very faint doubles. The other two are recent technologies that have launched a double star renaissance. These are lucky imaging and speckle interferometry, both of which can use electron-multiplying CCD cameras to allow short (30 ms or less) exposures that are read out at high speed with very low noise. Analysis of thousands of high speed exposures allows normal seeing limitations to be overcome so very close doubles can be accurately measured.

International double taxation

OpenAIRE

Körbl, Hugo

2012-01-01

1 Summary This thesis deals with the issue of international double taxation of income and capital and methods for its solution. International double taxation is an issue which states began to deal with in the late 19th century. This interest intensified after the First World War when also the League of Nations (predecessor of the United Nations) began to deal with international double taxation. Most attention the phenomenon of double taxation of income and capital with an international elemen...

Formation of double layers

International Nuclear Information System (INIS)

Leung, P.; Wong, A.Y.; Quon, B.H.

1981-01-01

Experiments on both stationary and propagating double layers and a related analytical model are described. Stationary double layers were produced in a multiple plasma device, in which an electron drift current was present. An investigation of the plasma parameters for the stable double layer condition is described. The particle distribution in the stable double layer establishes a potential profile, which creates electron and ion beams that excite plasma instabilities. The measured characteristics of the instabilities are consistent with the existence of the double layer. Propagating double layers are formed when the initial electron drift current is large. Ths slopes of the transition region increase as they propagate. A physical model for the formation of a double layer in the experimental device is described. This model explains the formation of the low potential region on the basis of the space charge. This space charge is created by the electron drift current. The model also accounts for the role of ions in double layer formation and explains the formation of moving double layers. (Auth.)

Nutritional interventions for optimizing healthy body composition in older adults in the community: an umbrella review of systematic reviews.

Science.gov (United States)

Schultz, Timothy J; Roupas, Peter; Wiechula, Richard; Krause, Debra; Gravier, Susan; Tuckett, Anthony; Hines, Sonia; Kitson, Alison

2016-08-01

Optimizing body composition for healthy aging in the community is a significant challenge. There are a number of potential interventions available for older people to support both weight gain (for those who are underweight) and weight loss (for overweight or obese people). While the benefits of weight gain for underweight people are generally clearly defined, the value of weight loss in overweight or obese people is less clear, particularly for older people. This umbrella review aimed to measure the effectiveness of nutritional interventions for optimizing healthy body composition in older adults living in the community and to explore theirqualitative perceptions. The participants were older adults, 60 years of age or older, living in the community. The review examinedsix types of nutritional interventions: (i) dietary programs, (ii) nutritional supplements, (iii) meal replacements, (iv) food groups, (v) food delivery support and eating behavior, and (vi) nutritional counselling or education. This umbrella review considered any quantitative systematic reviews and meta-analyses of effectiveness, or qualitative systematic reviews, or a combination (i.e. comprehensive reviews). The quantitative outcome measures of body composition were: (i) nutritional status (e.g. proportion of overweight or underweight patients); (ii) fat mass (kg), (iii) lean mass or muscle mass (kg), (iv) weight (kg) or BMI (kg/m), (v) bone mass (kg) or bone measures such as bone mineral density, and (vi) hydration status. The phenomena of interestwere the qualitative perceptions and experiences of participants. We developed an iterative search strategy for nine bibliometric databases and gray literature. Critical appraisal of 13 studies was conducted independently in pairs using standard Joanna Briggs Institute tools. Six medium quality and seven high quality studies were identified. Data was extracted independently in pairs from all 13 included studies using the standard Joanna Briggs Institute

Narrow-band imaging (NBI for improving the assessment of vocal fold leukoplakia and overcoming the umbrella effect.

Directory of Open Access Journals (Sweden)

H Klimza

Full Text Available It is crucial to find a balance between functional and oncological outcome when choosing an adequate method for the management of vocal fold leukoplakia. Therefore, a detailed examination is a milestone in the decision-making process.To examine whether narrow-band imaging (NBI can be helpful in vocal fold assessment in the case of leukoplakia and how to overcome the "umbrella effect"- understood as the submucosal vascular pattern hidden under the plaque.Prospective cohort of 41 consecutive patients. Inclusion criteria: vocal fold leukoplakia, no previous procedures (surgery, radiotherapy, and preoperative endoscopy with an optical filter for NBI. Two groups: "suspicious" and "normal", according to the submucosal microvascular pattern of peripheral regions of the mucosa surrounding the plaque, were distinguished. Patients were qualified for a full-thickness or partial-thickness biopsy, respectively. Criteria defining suspected characters were well-demarcated brownish areas with scattered brown spots corresponding to type IV, Va, Vb, and Vc NI classifications.In 22/41 (53.7% patients with "suspected" microvascular pattern, full-thickness biopsy was performed. Moderate and severe dysplasia was revealed in 15 type IV and 7 type Va NI patients. In 19/41 (46.3% patients with proper NBI vessel pattern treated by partial-thickness biopsy, hyperkeratosis was diagnosed. There was a strong correlation between the NBI pattern and final histology: Chi2 (2 = 41.0 (p = 0.0000.The results demonstrate that NBI endoscopic assessment of the submucosal microvascular pattern of mucosa surrounding the plaque can be an effective method to categorise the risk in vocal fold leukoplakia prior to treatment.

Double Trouble

NARCIS (Netherlands)

Elsaesser, Thomas; Kievit, Robert; Simons, Jan

1994-01-01

Double Trouble highlights the career of Dutch scriptwriter and television producer Chiem van Houweninge, well-known for his long-running TV comedy series and as author of episodes for TV detective series. Double Trouble gives Van Houweninge's own views on writing and filming in television prime

Method Evaluations for Adsorption Free Energy Calculations at the Solid/Water Interface through Metadynamics, Umbrella Sampling, and Jarzynski's Equality.

Science.gov (United States)

Wei, Qichao; Zhao, Weilong; Yang, Yang; Cui, Beiliang; Xu, Zhijun; Yang, Xiaoning

2018-03-19

Considerable interest in characterizing protein/peptide-surface interactions has prompted extensive computational studies on calculations of adsorption free energy. However, in many cases, each individual study has focused on the application of free energy calculations to a specific system; therefore, it is difficult to combine the results into a general picture for choosing an appropriate strategy for the system of interest. Herein, three well-established computational algorithms are systemically compared and evaluated to compute the adsorption free energy of small molecules on two representative surfaces. The results clearly demonstrate that the characteristics of studied interfacial systems have crucial effects on the accuracy and efficiency of the adsorption free energy calculations. For the hydrophobic surface, steered molecular dynamics exhibits the highest efficiency, which appears to be a favorable method of choice for enhanced sampling simulations. However, for the charged surface, only the umbrella sampling method has the ability to accurately explore the adsorption free energy surface. The affinity of the water layer to the surface significantly affects the performance of free energy calculation methods, especially at the region close to the surface. Therefore, a general principle of how to discriminate between methodological and sampling issues based on the interfacial characteristics of the system under investigation is proposed. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Communication: Estimating the initial biasing potential for λ-local-elevation umbrella-sampling (λ-LEUS) simulations via slow growth

Energy Technology Data Exchange (ETDEWEB)

Bieler, Noah S.; Hünenberger, Philippe H., E-mail: phil@igc.phys.chem.ethz.ch [Laboratory of Physical Chemistry, ETH Zürich, CH-8093 Zürich (Switzerland)

2014-11-28

In a recent article [Bieler et al., J. Chem. Theory Comput. 10, 3006–3022 (2014)], we introduced a combination of the λ-dynamics (λD) approach for calculating alchemical free-energy differences and of the local-elevation umbrella-sampling (LEUS) memory-based biasing method to enhance the sampling along the alchemical coordinate. The combined scheme, referred to as λ-LEUS, was applied to the perturbation of hydroquinone to benzene in water as a test system, and found to represent an improvement over thermodynamic integration (TI) in terms of sampling efficiency at equivalent accuracy. However, the preoptimization of the biasing potential required in the λ-LEUS method requires “filling up” all the basins in the potential of mean force. This introduces a non-productive pre-sampling time that is system-dependent, and generally exceeds the corresponding equilibration time in a TI calculation. In this letter, a remedy is proposed to this problem, termed the slow growth memory guessing (SGMG) approach. Instead of initializing the biasing potential to zero at the start of the preoptimization, an approximate potential of mean force is estimated from a short slow growth calculation, and its negative used to construct the initial memory. Considering the same test system as in the preceding article, it is shown that of the application of SGMG in λ-LEUS permits to reduce the preoptimization time by about a factor of four.

Communication: Estimating the initial biasing potential for λ-local-elevation umbrella-sampling (λ-LEUS) simulations via slow growth

International Nuclear Information System (INIS)

Bieler, Noah S.; Hünenberger, Philippe H.

2014-01-01

In a recent article [Bieler et al., J. Chem. Theory Comput. 10, 3006–3022 (2014)], we introduced a combination of the λ-dynamics (λD) approach for calculating alchemical free-energy differences and of the local-elevation umbrella-sampling (LEUS) memory-based biasing method to enhance the sampling along the alchemical coordinate. The combined scheme, referred to as λ-LEUS, was applied to the perturbation of hydroquinone to benzene in water as a test system, and found to represent an improvement over thermodynamic integration (TI) in terms of sampling efficiency at equivalent accuracy. However, the preoptimization of the biasing potential required in the λ-LEUS method requires “filling up” all the basins in the potential of mean force. This introduces a non-productive pre-sampling time that is system-dependent, and generally exceeds the corresponding equilibration time in a TI calculation. In this letter, a remedy is proposed to this problem, termed the slow growth memory guessing (SGMG) approach. Instead of initializing the biasing potential to zero at the start of the preoptimization, an approximate potential of mean force is estimated from a short slow growth calculation, and its negative used to construct the initial memory. Considering the same test system as in the preceding article, it is shown that of the application of SGMG in λ-LEUS permits to reduce the preoptimization time by about a factor of four

The Plastic Potential, Double-slip, Double-spin and Viscoplasticity

Science.gov (United States)

Harris, David

2010-05-01

In this paper we describe two classical models for rate-independent behaviour of granular materials, namely the plastic potential and the double shearing model, emphasising their ill-posedness. We then describe a model, called the doubleslip and double-spin model which generalises the plastic potential model and is closely related to the double shearing model. This new model eliminates the causes of the ill-posedness in the classical models and provides a suitable basis for the analysis of the deformation and flow of granular materials in the rate-independent regime. There has been considerable recent interest in the intermediate regime between densely-packed, rate-independent, quasistatic flow and the rate-dependent dilute gaseous regime. In this intermediate regime the material also exhibits a degree of ratedependence. The natural extension of a rate-independent plasticity model to incorporate rate-dependent material behaviour is by way of viscoplasticity. The archetypal example here is the Bingham material which generalises a von Mises type plasticity model and introduces a viscosity parameter into the model. We propose an extension of the double-slip and double-spin model to incorporate viscosity, thereby extending the range of the model to incorporate rate-dependent behaviour. The new model is then applied to a simplified problem of pipe flow.

Double layers in space

International Nuclear Information System (INIS)

Carlqvist, P.

1982-07-01

For more than a decade it has been realised that electrostatic double layers are likely to occur in space. We briefly discuss the theoretical background of such double layers. Most of the paper is devoted to an account of the observational evidence for double layers in the ionosphere and magnetosphere of the Earth. Several different experiments are reviewed including rocket and satellite measurements and ground based observations. It is concluded that the observational evidence for double layers in space is very strong. The experimental results indicate that double layers with widely different properties may exist in space. (Author)

Double layers in space

International Nuclear Information System (INIS)

Carlqvist, P.

1982-01-01

For more than a decade it has been realised that electrostatic double layers are likely to occur in space. The author briefly discusses the theoretical background of such double layers. Most of the paper is devoted to an account of the observational evidence for double layers in the ionosphere and magnetosphere of the Earth. Several different experiments are reviewed including rocket and satellite measurements and ground based observations. It is concluded that the observational evidence for double layers in space is very strong. The experimental results indicate that double layers with widely different properties may exist in space. (Auth.)

Double-continuum wave functions and double-photoionization cross sections of two-electron systems

International Nuclear Information System (INIS)

Tiwary, S.N.

1996-09-01

The present review briefly presents the growing experimental as well as theoretical interests in recent years in the double-continuum wave functions and double-photoionization cross sections of two-electron systems. The validity of existing double-continuum wave functions is analyzed and the importance of electronic correlations in both the initial as well as final states wave functions involved in the transition amplitude for double-photoionization process is demonstrated. At present, we do not have comprehensive and practical double-continuum wave functions which account the full correlation of two-electron in the continuum. Basic difficulties in making accurate theoretical calculations of double ionization by a single high energy photon especially in the vicinity of the threshold, where the correlation plays an important role, are discussed. Illuminating, illustrative and representative examples are presented in order to show the present status and the progress in this field. Future challenges and directions, in high-precision double-photoionization cross sections calculations, have been discussed and suggested. (author). 133 refs, 9 figs

Double Outlet Right Ventricle

Science.gov (United States)

... Right Ventricle Menu Topics Topics FAQs Double Outlet Right Ventricle Double outlet right ventricle (DORV) is a rare form of congenital heart disease. En español Double outlet right ventricle (DORV) is a rare form of congenital ...

Congenital double-double lip: A rare case report

Directory of Open Access Journals (Sweden)

Swati Phore

2017-01-01

Full Text Available A double lip is a rare anomaly characterized by a horizontal fold of redundant mucosal tissue that is situated proximal to the vermilion border. It may be either congenital or acquired and has no gender or race predilection. It occurs most often in the upper lip, although both upper and lower lips are occasionally involved. Surgical intervention (simple excision produces good functional and cosmetic results. In this report, a case of a nonsyndromic congenital maxillary double upper lip and lower lip, both are described. Double lip is of special interest in dental profession as a dental surgeon is normally the first one to diagnose this rare and uncommon condition. Authors hereby discuss a very rare condition in which both upper and lower lips are involved.

Solvent-free preparation of polylactic acid fibers by melt electrospinning using umbrella-like spray head and alleviation of problematic thermal degradation

Directory of Open Access Journals (Sweden)

Liu Yong

2012-01-01

Full Text Available Melt electrospinning is an even simpler and safer method compared with the solution electrospinning in the production of ultra-fine fibers. Polylactic acid (PLA is a biodegradable and resorbable aliphatic ester that has received significant attention in recent years. PLA is easily degradable at high temperature in the process of melt electrospinning. High efficient fibers were made using our designed umbrella-like spray head spinning facility in this work. To find how to alleviate the problematic degradation and what factors could be relevant to degradation, temperature, relative molecular mass, Differential Scanning Calorimeter and X-ray Diffraction patterns before and after spinning were investigated and compared with each other. Results showed that fibers were facile shorten and fractured when spun at 245°C while the relative molecular mass of PLA fibers decreased markedly as compared with that spun at 210°C. To hinder the degradation, couple of experimental efforts were implemented with adding antioxidants, raising spinning voltage, lowering temperature, and reducing residence time. After such efforts, it was observed that the relative molecular mass of the PLA fibers was higher than those without inputting any efforts. The effect of antioxidant 1010 was found the most promising on the alleviation of PLA problematic thermal degradation.

Efficacy, tolerability, and safety of non-pharmacological therapies for chronic pain: An umbrella review on various CAM approaches.

Science.gov (United States)

Houzé, Bérengère; El-Khatib, Héjar; Arbour, Caroline

2017-10-03

Complementary and alternative medicine (CAM) therapies may be used as a non-pharmacological approach to chronic pain management. While hundreds of trials about individual CAM modality have been conducted, a comprehensive overview of their results is currently lacking for pain clinicians and researchers. This umbrella review synthesized the quality of meta-analytic evidence supporting the efficacy, tolerability and safety of CAM therapies for the management of chronic pain. MEDLINE, EMBASE, CINAHL, and CENTRAL were searched from October 1991 to November 2016. Reviews of clinical trials (randomized and non-randomized) with meta-analysis investigating the utility of any CAM modality for chronic pain were eligible. Pain relief post-intervention was the main outcome and secondary outcomes included patients' adherence and incidence of adverse effects during CAM protocol. Twenty-six reviews (207 clinical trials, >12,000 participants) about 18 CAM modalities, falling under natural products, mind and body practices or other complementary health approaches were included. Inhaled cannabis, graded motor imagery, and Compound Kushen injection (a form of Chinese medicine) were found the most efficient (with moderate-to-high effect sizes and low heterogeneity) and tolerable (≥80% of adherence to study protocols) for chronic pain relief. When reported, adverse effects related to these CAM were minor. Although several CAM were found effective for chronic pain relief, it remains unclear when these modalities are a reasonable choice against or in conjunction with mainstream treatments. In that sense, future research with a clear emphasis on concurrent evaluation of CAM overall efficacy and patient adherence/tolerance is needed. Copyright © 2017 Elsevier Inc. All rights reserved.

Analyzing Double Image Illusion through Double Indiscernibility and Lattice Theory

Directory of Open Access Journals (Sweden)

Kohei Sonoda

2011-10-01

Full Text Available The figure-ground division plays a fundamental role in all image perceptions. Although there are a lot of studies about extraction of a figure such as detection of edges or grouping of texture, there are few discussions about a relationship between obtained figure and ground. We focused on double image illusions having two complementary relationships be- tween figure and ground and analyzed them. We divided the double image illusions according to two different interpretations and using these divisions we extracted and analyzed their logical structures by lattices derived from rough sets that we had developed. As a result we discovered unusual logical structures in double image illusions.

Project Half Double

DEFF Research Database (Denmark)

Svejvig, Per; Ehlers, Michael; Adland, Karoline Thorp

activities carried out within the framework of the projects. The formal part of Project Half Double was initiated in June 2015. We started out by developing, refining and testing the Half Double methodology on seven pilot projects in the first phase of the project, which will end June 2016. The current......Project Half Double has a clear mission to succeed in finding a project methodology that can increase the success rate of our projects while increasing the speed at which we generate new ideas and develop new products and services. Chaos and complexity should be seen as a basic condition...... and as an opportunity rather than a threat and a risk. We are convinced that by doing so, we can strengthen Denmark’s competitiveness and play an important role in the battle for jobs and future welfare. The overall goal is to deliver “projects in half the time with double the impact”, where projects in half the time...

Project Half Double

DEFF Research Database (Denmark)

Svejvig, Per; Gerstrøm, Anna; Frederiksen, Signe Hedeboe

The Half Double mission: Project Half Double has a clear mission. We want to succeed in finding a project methodology that can increase the success rate of our projects while increasing the development speed of new products and services. We are convinced that by doing so we can strengthen...... the competitiveness of Denmark and play an important role in the battle for jobs and future welfare. The overall goal is to deliver “Projects in half the time with double the impact” where projects in half the time should be understood as half the time to impact (benefit realization, effect is achieved......) and not as half the time for project execution. The Half Double project journey: It all began in May 2013 when we asked ourselves: How do we create a new and radical project paradigm that can create successful projects? Today we are a movement of hundreds of passionate project people, and it grows larger...

Double parton scattering in the ultraviolet. Addressing the double counting problem

Energy Technology Data Exchange (ETDEWEB)

Diehl, Markus [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Gaunt, Jonathan R. [Nikhef Theory Group, Amsterdam (Netherlands); Amsterdam VU Univ. (Netherlands)

2016-11-15

An important question in the theory of double parton scattering is how to incorporate the possibility of the parton pairs being generated perturbatively via 1→ 2splitting into the theory, whilst avoiding double counting with single parton scattering loop corrections. Here, we describe a consistent approach for solving this problem, which retains the notion of double parton distributions (DPDs) for individual hadrons. Further, we discuss the construction of appropriate model DPDs in our framework, and the use of these to compute the DPS part, presenting DPS 'luminosities' from our model DPDs for a few sample cases.

Decades with four double triodes; Decades a quatre doubles triodes

Energy Technology Data Exchange (ETDEWEB)

Wahl, R [Commissariat a l' Energie Atomique, Lab. du Fort de Chatillon, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

1952-07-01

Decades with four double triodes The described decade consists of four double triodes and four crystals germanium; which has the following characteristics: - Attack in negative impulses. - Sensitivity 12 volts {+-} 40 % for signals of 1 {mu}s about. - Time of resolution 2,5 {mu}s. - Voltage 250 v {+-} 40 %. - heating 6,3 v {+-} 40 %. - Tolerance on the values of the elements of installation 10%. (author) [French] La decade decrite comprend quatre doubles triodes et quatre cristaux germanium; elle a les caracteristiques suivantes: - Attaque en impulsions negatives. - Sensiblite 12 volts {+-} 40 % pour des signaux de 1 {mu}s environ. - Temps de resolution 2,5 {mu}s. - Alimentation 250 v {+-} 40 %. - Chauffage 6,3 v {+-} 40 %. - Tolerance sur les valeurs des elements de montage l0 %. (auteur)

Global effects of double layers

International Nuclear Information System (INIS)

Raad, M.A.

1984-12-01

Locally the formation of an electrostatic double layer in a current carrying plasma leads to a direct acceleration of particles which may penetrate far into the surrounding medium. The potential across the double layer, giving this acceleration, must be maintained by the external system and is a basic parameter for the local to global coupling. The double layer potential is associated with an electric field parallel to the magnetic field. In general this leads to a magnetohydrodynamic relaxation of the surrounding medium providing the influx of energy which is dissipated by the double layer. The double layer potential is limited as is the maximum possible rate of energy influx. If the global response of the external medium can be represented by an external circuit and if an equivalent circuit element can be found to represent the double layer, for example a negative resistance for intermediate time scales, it is possible to give a description of the dynamics and stability of the whole system. (Author)

Who is entitled to double effect?

Science.gov (United States)

Boyle, J

1991-10-01

The doctrine of double effect continues to be an important tool in bioethical casuistry. Its role within the Catholic moral tradition continues, and there is considerable interest in it by contemporary moral philosophers. But problems of justification and correct application remain. I argue that if the traditional Catholic conviction that there are exceptionless norms prohibiting inflicting some kinds of harms on people is correct, then double effect is justified and necessary. The objection that double effect is superfluous is a rejection of that normative conviction, not a refutation of double effect itself. This justification suggests the correct way of applying double effect to controversial cases. But versions of double effect which dispense with the absolutism of the Catholic tradition lack justification and fall to the objection that double effect is an unnecessary complication.

Design and delivery of the diamond double double bend achromat project

International Nuclear Information System (INIS)

Kay, J.; Hammond, N. P.; Thomson, A.

2016-01-01

A major project is underway at Diamond Light Source to remove one of the 24 Double Bend Achromat (DBA) Storage Ring cells and replace it with a Double Double Bend Achromat (DDBA). In this way a new Insertion Device (ID) straight can be created and so ID light can be produced and delivered to a beamline previously only capable of receiving Bending Magnet (BM) radiation. This project is in support of the micro-focus Protein Crystallography (MX) beamline VMX-m which is scheduled to take users towards the end of 2017. This paper describes the Engineering Design of the DDBA project in more detail and gives the current status of the project.

Design and delivery of the diamond double double bend achromat project

Energy Technology Data Exchange (ETDEWEB)

Kay, J., E-mail: jim.kay@diamond.ac.uk; Hammond, N. P.; Thomson, A. [Diamond Light Source, Didcot, Oxfordshire, UK, OX11 0DE (United Kingdom)

2016-07-27

A major project is underway at Diamond Light Source to remove one of the 24 Double Bend Achromat (DBA) Storage Ring cells and replace it with a Double Double Bend Achromat (DDBA). In this way a new Insertion Device (ID) straight can be created and so ID light can be produced and delivered to a beamline previously only capable of receiving Bending Magnet (BM) radiation. This project is in support of the micro-focus Protein Crystallography (MX) beamline VMX-m which is scheduled to take users towards the end of 2017. This paper describes the Engineering Design of the DDBA project in more detail and gives the current status of the project.

Double Girder Bridge Crane with Double Cycling: Scheduling Strategy and Performance Evaluation

Directory of Open Access Journals (Sweden)

Dandan Wang

2014-01-01

Full Text Available This paper introduces a novel quay crane design, double girder bridge crane (DGBC. DGBC is capable of handling containers of two adjacent bays simultaneously, avoiding crane collisions, saving travelling and reposition cost, and eventually improving terminal efficiency. This problem is formulated as a resource-constrained project scheduling with objective to minimize the maximum completion time. A two-stage heuristic algorithm is proposed in which an operating sequences on each bay is obtained by double cycling, and the integrated timetable for both bays is constructed by solving resource conflicts using the proposed minimum cost strategy. We examine effectiveness and performance of applying DGBC with double cycling. A case study is presented to illustrate how DGBC works with the two-stage method. Three extreme cases with respective conflict types are investigated to develop the performance bounds of DGBC with double cycling. The results show that DGBC can significantly improve terminal productivity, and outperforms single girder crane in both makespan and the lift operation percentage. The highest DGBC efficiency does not require maximum double cycles in two bay schedules; rather the integrated timetable for two bays is the main contribution to the DGBC performance as it yields better cooperation between two spreaders and the driver.

On the physics of relativistic double layers

International Nuclear Information System (INIS)

Carlqvist, P.

1982-06-01

A model of a strong, time-independent, and relativistic double layer is studied. Besides double layers having the electric field parallel to the current the model also describes a certain type of oblique double layers. The 'Langmuir condition' (ratio of ion current density to electron current density) as well as an expression for the potential drop of the double layer are derived. Furthermore, the distribution of charged particles, electric field, and potential within the double layer are clarified and discussed. It is found that the properties of relativistic double layers differ substantially from the properties of corresponding non-relativistic double layers. (Author)

Transcatheter closure of re-canalized patent ductus arteriosus after surgical ligation

International Nuclear Information System (INIS)

Zhang Qingqiao; Jiang Shiliang; Huang Lianjun; Zhao Shihua; Zheng Hong; Ling Jian; Jin Jinglin; Xu Zhongying; Xie Ruolan; Dai Ruping

2002-01-01

Objective: To evaluate the effectiveness of transcatheter closure of re-canalized patent ductus arteriosus (PDA) after surgical ligation. Methods: Between June 1995 and November 2000, 14 patients (5 male, 9 female) with re-canalized PDA after surgical ligation underwent transcatheter closure, their median age was 13 years (range 4 to 48 years). The time between surgical ligation and the interventional procedure ranged from one month to twenty-two years. Implantations of Amplatzer duct occluder and Rashkind occluder were performed trans-venously. Cook coil occlusions was performed trans-arterially. Follow-up with X-ray radiograph and echocardiography was made 24 hours, 1, 3, 6 months, and more than 1 year after the procedure. Results: Twelve PDAs were of funnel shape, and the remaining two PDAs were of tubular shape. The median minimum diameter of re-canalized PDA after ligation was 4 mm (range 1 to 8 mm). Aortograms ten minutes after closure showed complete closure and trivial residual shunt in 11 and 3 patients, respectively. The technical success rate was 100%, and there were no complications. Echocardiography showed complete closure in all patients within 24 hours. All patients were discharged in one to two days after the procedure. At a follow-up of one to eighteen months in ten patients, there were no migration of devices and residual PDA. Conclusion: Transcatheter closure using Amplatzer duct occluder, coil (Cook company or Pfm company) and Rashkind occluder was an effective method for patients with re-canalized PDA after surgical ligation. It may be an alternative to second surgery owing to its safety, reliability, min-invasiveness, and short hospitalization

Transcatheter closure of re-canalized patent ductus arteriosus after surgical ligation

Energy Technology Data Exchange (ETDEWEB)

Qingqiao, Zhang; Shiliang, Jiang; Lianjun, Huang; Shihua, Zhao; Hong, Zheng; Jian, Ling; Jinglin, Jin; Zhongying, Xu; Ruolan, Xie; Ruping, Dai [Chinese Academy of Medical Science, Beijing Union Medical College, Beijing (China). Cardiovascular Inst. and Fuwai Hospital, Dept. of Radiology

2002-02-01

Objective: To evaluate the effectiveness of transcatheter closure of re-canalized patent ductus arteriosus (PDA) after surgical ligation. Methods: Between June 1995 and November 2000, 14 patients (5 male, 9 female) with re-canalized PDA after surgical ligation underwent transcatheter closure, their median age was 13 years (range 4 to 48 years). The time between surgical ligation and the interventional procedure ranged from one month to twenty-two years. Implantations of Amplatzer duct occluder and Rashkind occluder were performed trans-venously. Cook coil occlusions was performed trans-arterially. Follow-up with X-ray radiograph and echocardiography was made 24 hours, 1, 3, 6 months, and more than 1 year after the procedure. Results: Twelve PDAs were of funnel shape, and the remaining two PDAs were of tubular shape. The median minimum diameter of re-canalized PDA after ligation was 4 mm (range 1 to 8 mm). Aortograms ten minutes after closure showed complete closure and trivial residual shunt in 11 and 3 patients, respectively. The technical success rate was 100%, and there were no complications. Echocardiography showed complete closure in all patients within 24 hours. All patients were discharged in one to two days after the procedure. At a follow-up of one to eighteen months in ten patients, there were no migration of devices and residual PDA. Conclusion: Transcatheter closure using Amplatzer duct occluder, coil (Cook company or Pfm company) and Rashkind occluder was an effective method for patients with re-canalized PDA after surgical ligation. It may be an alternative to second surgery owing to its safety, reliability, min-invasiveness, and short hospitalization.

Simulation of plasma double-layer structures

International Nuclear Information System (INIS)

Borovsky, J.E.; Joyce, G.

1982-01-01

Electrostatic plasma double layers are numerically simulated by means of a magnetized 2 1/2-dimensional particle-in-cell method. The investigation of planar double layers indicates that these one-dimensional potential structures are susceptible to periodic disruption by instabilities in the low-potential plasmas. Only a slight increase in the double-layer thickness with an increase in its obliqueness to the magnetic field is observed. Weak magnetization results in the double-layer electric-field alignment of accelerated particles and strong magnetization results in their magnetic-field alignment. The numerial simulations of spatially periodic two-dimensional double layers also exhibit cyclical instability. A morphological invariance in two-dimensional double layers with respect to the degree of magnetization implies that the potential structures scale with Debye lengths rather than with gyroradii. Electron-beam excited electrostatic electron-cyclotron waves and (ion-beam driven) solitary waves are present in the plasmas adjacent to the double layers

Double layers and circuits in astrophysics

International Nuclear Information System (INIS)

Alfven, H.

1986-05-01

As the rate of energy release in a double layer with voltage DeltaV is P corresponding to IDeltaV, a double layer must be treated part of a circuit which delivers the current I. As neither double layer nor circuit can be derived from magnetofluid models of a plasma, such models are useless for treating energy transfer by menas of double layers. They must be replaced by particle models and circuit theory. A simple circuit is suggested which is applied to the energizing of auroroal particles, to solar flares, and to intergalactic double radio sources. Application to the heliospheric current systems leads to the prediction of two double layers on the sun's axis which may give radiations detectable from earth. Double layers in space should be classified as a new type of celestial object (one example is the double radio sources). It is tentatively suggested in X-ray and gamma-ray bursts may be due to exploding double layers (although annihilation is an alternative energy source). A study of how a number of the most used textbooks in astrophysics treat important concepts like double layers, critical velocity, pinch effects and circuits is made. It is found that students using these textbooks remain essentially ignorant of even the existence of these, in spite of the fact that some of them have been well known for half a centry (e.g., double layers, Langmuir, 1929: pinch effect, Bennet, 1934). The conclusion is that astrophysics is too important to be left in the hands of the astrophysicist. Earth bound and space telescope data must be treated by scientists who are familiar with laboratory and magnetospheric physics and circuit theory, and of course with modern plasma theory. At least by volume the universe consists to more than 99 percent of plasma, and electromagnetic forces are 10/sup39/ time stronger than gravitation

Optical and Electrical Characteristics of Graphene Double Layer Formed by a Double Transfer of Graphene Single Layers.

Science.gov (United States)

Kim, Young Jun; Bae, Gi Yoon; Chun, Sungwoo; Park, Wanjun

2016-03-01

We demonstrate formation of double layer graphene by means of a double transfer using two single graphene layers grown by a chemical vapor deposition method. It is observed that shiftiness and broadness in the double-resonance of Raman scattering are much weaker than those of bilayer graphene formed naturally. Transport characteristics examined from transmission line measurements and field effect transistors show the similar behavior with those of single layer graphene. It indicates that interlayer separation, in electrical view, is large enough to avoid correlation between layers for the double layer structure. It is also observed from a transistor with the double layer graphene that molecules adsorpted on two inner graphene surfaces in the double layered structure are isolated and conserved from ambient environment.

Double deflation and aggregation

NARCIS (Netherlands)

Dietzenbacher, Erik; Hoen, A.R.

Published input-output tables in constant prices are relatively scarce. Therefore, input-output tables often have to be deflated by the practitioners themselves. The method of double deflation is used predominantly for this purpose. The present paper shows that the double-deflation method is subject

Congenital maxillary double lip

Directory of Open Access Journals (Sweden)

Dinesh Singh Chauhan

2012-01-01

Full Text Available Double lip, also referred to as "macrocheilia," is a rare anomaly which affects the upper lip more commonly than the lower lip. It consists of a fold of excess or redundant hypertrophic tissue on the mucosal side of the lip. The congenital double lip is believed to be present at birth and becomes more prominent after eruption of teeth. It affects esthetics and also interferes with speech and mastication. Simple surgical excision produces good functional and cosmetic results. We report a case of a non-syndromic congenital maxillary double lip in a 21-year-old male patient.

Z₂-double cyclic codes

OpenAIRE

Borges, J.

2014-01-01

A binary linear code C is a Z2-double cyclic code if the set of coordinates can be partitioned into two subsets such that any cyclic shift of the coordinates of both subsets leaves invariant the code. These codes can be identified as submodules of the Z2[x]-module Z2[x]/(x^r − 1) × Z2[x]/(x^s − 1). We determine the structure of Z2-double cyclic codes giving the generator polynomials of these codes. The related polynomial representation of Z2-double cyclic codes and its duals, and the relation...

Double supergeometry

Energy Technology Data Exchange (ETDEWEB)

Cederwall, Martin [Division for Theoretical Physics, Department of Physics, Chalmers University of Technology,SE 412 96 Gothenburg (Sweden)

2016-06-27

A geometry of superspace corresponding to double field theory is developed, with type I I supergravity in D=10 as the main example. The formalism is based on an orthosymplectic extension OSp(d,d|2s) of the continuous T-duality group. Covariance under generalised super-diffeomorphisms is manifest. Ordinary superspace is obtained as a solution of the orthosymplectic section condition. A systematic study of curved superspace Bianchi identities is performed, and a relation to a double pure spinor superfield cohomology is established. A Ramond-Ramond superfield is constructed as an infinite-dimensional orthosymplectic spinor. Such objects in minimal orbits under the OSp supergroup (“pure spinors”) define super-sections.

Some theoretical aspects of electrostatic double layers

International Nuclear Information System (INIS)

Carlqvist, P.

1978-11-01

A review is presented of the main results of the theoretical work on electrostatic double layers. The general properties of double layers are first considered. Then the time-independent double layer is discussed. The discussion deals with the potential drop, the thickness, and some necessary criteria for the existence and stability of the layer. As a complement to the study of the timeindependent double layer a few remarks are also made upon the timedependent double layer. Finally the question of how double layers are formed and maintained is treated. Several possible formation mechanisms are considered. (author)

Double Dirac cones in phononic crystals

KAUST Repository

Li, Yan

2014-07-07

A double Dirac cone is realized at the center of the Brillouin zone of a two-dimensional phononic crystal (PC) consisting of a triangular array of core-shell-structure cylinders in water. The double Dirac cone is induced by the accidental degeneracy of two double-degenerate Bloch states. Using a perturbation method, we demonstrate that the double Dirac cone is composed of two identical and overlapping Dirac cones whose linear slopes can also be accurately predicted from the method. Because the double Dirac cone occurs at a relatively low frequency, a slab of the PC can be mapped onto a slab of zero refractive index material by using a standard retrieval method. Total transmission without phase change and energy tunneling at the double Dirac point frequency are unambiguously demonstrated by two examples. Potential applications can be expected in diverse fields such as acoustic wave manipulations and energy flow control.

Double Dirac cones in phononic crystals

KAUST Repository

Li, Yan; Wu, Ying; Mei, Jun

2014-01-01

A double Dirac cone is realized at the center of the Brillouin zone of a two-dimensional phononic crystal (PC) consisting of a triangular array of core-shell-structure cylinders in water. The double Dirac cone is induced by the accidental degeneracy of two double-degenerate Bloch states. Using a perturbation method, we demonstrate that the double Dirac cone is composed of two identical and overlapping Dirac cones whose linear slopes can also be accurately predicted from the method. Because the double Dirac cone occurs at a relatively low frequency, a slab of the PC can be mapped onto a slab of zero refractive index material by using a standard retrieval method. Total transmission without phase change and energy tunneling at the double Dirac point frequency are unambiguously demonstrated by two examples. Potential applications can be expected in diverse fields such as acoustic wave manipulations and energy flow control.

Double layers above the aurora

International Nuclear Information System (INIS)

Temerin, M.; Mozer, F.S.

1987-01-01

Two different kinds of double layers were found in association with auroral precipitation. One of these is the so-called electrostatic shock, which is oriented at an oblique angle to the magnetic field in such a way that the perpendicular electric field is much larger than the parallel electric field. This type of double layer is often found at the edges of regions of upflowing ion beams and the direction of the electric fields in the shock points toward the ion beam. The potential drop through the shock can be several kV and is comparable to the total potential needed to produce auroral acceleration. Instabilities associated with the shock may generate obliquely propagating Alfven waves, which may accelerate electrons to produce flickering auroras. The flickering aurora provides evidence that the electrostatic shock may have large temporal fluctuations. The other kind of double layer is the small-amplitude double layer found in regions of upward flowing in beams, often in association with electrostatic ion cyclotron waves. The parallel and perpendicular electric fields in these structures are comparable in magnitude. The associated potentials are a few eV. Since many such double layers are found in regions of upward flowing ion beams, the combined potential drop through a set of these double layers can be substantial

Developmental Coordination Disorder, an umbrella term for motor impairments in children: nature and co-morbid disorders

Directory of Open Access Journals (Sweden)

Laurence eVaivre-Douret

2016-04-01

neuropsychomotor assessment, including neuromuscular tone examination, using appropriate standardized neurodevelopmental tools (common tasks across ages with age-related normative data in order to distinguish motor impairments gathered under the umbrella term of developmental coordination disorders (subcortical vs cortical. Mild spasticity in the gastrocnemius muscles, such as phasic stretch reflex (PSR, suggests disturbances of the motor pathway, increasing impairment of gross and fine motricity.These findings contribute to understanding the nature of motor disorders in DCD

Reliability Modeling of Double Beam Bridge Crane

Science.gov (United States)

Han, Zhu; Tong, Yifei; Luan, Jiahui; Xiangdong, Li

2018-05-01

This paper briefly described the structure of double beam bridge crane and the basic parameters of double beam bridge crane are defined. According to the structure and system division of double beam bridge crane, the reliability architecture of double beam bridge crane system is proposed, and the reliability mathematical model is constructed.

Double-trace deformations of conformal correlations

Science.gov (United States)

Giombi, Simone; Kirilin, Vladimir; Perlmutter, Eric

2018-02-01

Large N conformal field theories often admit unitary renormalization group flows triggered by double-trace deformations. We compute the change in scalar four-point functions under double-trace flow, to leading order in 1/ N. This has a simple dual in AdS, where the flow is implemented by a change of boundary conditions, and provides a physical interpretation of single-valued conformal partial waves. We extract the change in the conformal dimensions and three-point coefficients of infinite families of double-trace composite operators. Some of these quantities are found to be sign-definite under double-trace flow. As an application, we derive anomalous dimensions of spinning double-trace operators comprised of non-singlet constituents in the O( N) vector model.

Double ambidexterity

DEFF Research Database (Denmark)

Kaulio, Matti; Thorén, Kent; Rohrbeck, René

2017-01-01

We leverage the business model innovation and ambidexterity literature to investigate a contradictory case, the Swedish-Finnish Telecom operator TeliaSonera. Despite being challenged by three major disruptions, the company not only still exists but also enjoys remarkably good financial performance....... Building on extant archival data and interviews, we carefully identify and map 26 organizational responses during 1992–2016. We find that the firm has overcome three critical phases by experimenting and pioneering with portfolios of business models and/or technological innovations. We describe...... this behaviour as double ambidexterity. We use an in-depth case study to conceptualize double ambidexterity and discuss its impact on the business's survival and enduring success....

Coulomb double helical structure

Science.gov (United States)

Kamimura, Tetsuo; Ishihara, Osamu

2012-01-01

Structures of Coulomb clusters formed by dust particles in a plasma are studied by numerical simulation. Our study reveals the presence of various types of self-organized structures of a cluster confined in a prolate spheroidal electrostatic potential. The stable configurations depend on a prolateness parameter for the confining potential as well as on the number of dust particles in a cluster. One-dimensional string, two-dimensional zigzag structure and three-dimensional double helical structure are found as a result of the transition controlled by the prolateness parameter. The formation of stable double helical structures resulted from the transition associated with the instability of angular perturbations on double strings. Analytical perturbation study supports the findings of numerical simulations.

Nonlocal Poisson-Fermi double-layer models: Effects of nonuniform ion sizes on double-layer structure

Science.gov (United States)

Xie, Dexuan; Jiang, Yi

2018-05-01

This paper reports a nonuniform ionic size nonlocal Poisson-Fermi double-layer model (nuNPF) and a uniform ionic size nonlocal Poisson-Fermi double-layer model (uNPF) for an electrolyte mixture of multiple ionic species, variable voltages on electrodes, and variable induced charges on boundary segments. The finite element solvers of nuNPF and uNPF are developed and applied to typical double-layer tests defined on a rectangular box, a hollow sphere, and a hollow rectangle with a charged post. Numerical results show that nuNPF can significantly improve the quality of the ionic concentrations and electric fields generated from uNPF, implying that the effect of nonuniform ion sizes is a key consideration in modeling the double-layer structure.

The effects of public health policies on population health and health inequalities in European welfare states: protocol for an umbrella review.

Science.gov (United States)

Thomson, Katie; Bambra, Clare; McNamara, Courtney; Huijts, Tim; Todd, Adam

2016-04-08

The welfare state is potentially an important macro-level determinant of health that also moderates the extent, and impact, of socio-economic inequalities in exposure to the social determinants of health. The welfare state has three main policy domains: health care, social policy (e.g. social transfers and education) and public health policy. This is the protocol for an umbrella review to examine the latter; its aim is to assess how European welfare states influence the social determinants of health inequalities institutionally through public health policies. A systematic review methodology will be used to identify systematic reviews from high-income countries (including additional EU-28 members) that describe the health and health equity effects of upstream public health interventions. Interventions will focus on primary and secondary prevention policies including fiscal measures, regulation, education, preventative treatment and screening across ten public health domains (tobacco; alcohol; food and nutrition; reproductive health services; the control of infectious diseases; screening; mental health; road traffic injuries; air, land and water pollution; and workplace regulations). Twenty databases will be searched using a pre-determined search strategy to evaluate population-level public health interventions. Understanding the impact of specific public health policy interventions will help to establish causality in terms of the effects of welfare states on population health and health inequalities. The review will document contextual information on how population-level public health interventions are organised, implemented and delivered. This information can be used to identify effective interventions that could be implemented to reduce health inequalities between and within European countries. PROSPERO CRD42016025283.

Double-reed exhaust valve engine

Science.gov (United States)

Bennett, Charles L.

2015-06-30

An engine based on a reciprocating piston engine that extracts work from pressurized working fluid. The engine includes a double reed outlet valve for controlling the flow of low-pressure working fluid out of the engine. The double reed provides a stronger force resisting closure of the outlet valve than the force tending to open the outlet valve. The double reed valve enables engine operation at relatively higher torque and lower efficiency at low speed, with lower torque, but higher efficiency at high speed.

Biomechanical evaluation of knotless anatomical double-layer double-row rotator cuff repair: a comparative ex vivo study.

Science.gov (United States)

Hepp, Pierre; Osterhoff, Georg; Engel, Thomas; Marquass, Bastian; Klink, Thomas; Josten, Christoph

2009-07-01

The layered configuration of the rotator cuff tendon is not taken into account in classic rotator cuff tendon repair techniques. The mechanical properties of (1) the classic double-row technique, (2) a double-layer double-row (DLDR) technique in simple suture configuration, and (3) a DLDR technique in mattress suture configuration are significantly different. Controlled laboratory study. Twenty-four sheep shoulders were assigned to 3 repair groups of full-thickness infraspinatus tears: group 1, traditional double-row repair; group 2, DLDR anchor repair with simple suture configuration; and group 3, DLDR knotless repair with mattress suture configuration. After ultrasound evaluation of the repair, each specimen was cyclically loaded with 10 to 100 N for 50 cycles. Each specimen was then loaded to failure at a rate of 1 mm/s. There were no statistically significant differences among the 3 testing groups for the mean footprint area. The cyclic loading test revealed no significant difference among the 3 groups with regard to elongation. For the load-to-failure test, groups 2 and 3 showed no differences in ultimate tensile load when compared with group 1. However, when compared to group 2, group 3 was found to have significantly higher values regarding ultimate load, ultimate elongation, and energy absorbed. The DLDR fixation techniques may provide strength of initial repair comparable with that of commonly used double-row techniques. When compared with the knotless technique with mattress sutures, simple suture configuration of DLDR repair may be too weak. Knotless DLDR rotator cuff repair may (1) restore the footprint by the use of double-row principles and (2) enable restoration of the shape and profile. Double-layer double-row fixation in mattress suture configuration has initial fixation strength comparable with that of the classic double-row fixation and so may potentially improve functional results of rotator cuff repair.

Delivery of double singleton pregnancies in a woman with a double uterus, double cervix, and complete septate vagina

Directory of Open Access Journals (Sweden)

Ming-Jie Yang

2015-12-01

Full Text Available Uterine anomalies involving a double uterus, double cervix, also known as didelphys uterus, and complete septate vagina are rarely seen and have an associated fertility problem. However, artificial reproductive technology with embryo transfers can help solve this fertility challenge. Conception in the uterus in just one side is commonly seen for embryos, which are always transferred through the usually used (dilated vagina. We here present a patient with the above uterine anomaly who conceived with the aid of in vitro fertilization and embryo transfer to both uterine cavities under general anesthesia, which resulted in successful double singleton pregnancies with one fetus in each uterus. With intensive prenatal care, the pregnancy course for each fetus was rather uneventful. Although both fetuses were in cephalic presentation, cesarean section was performed at the 39th week of gestation with good outcomes in order to preclude anticipated difficulties if the baby had been delivered through the rarely dilated vagina. However, order of birth between the two fetuses was a crucial decision during the operation.

Alternate Double Single Track Lines

Energy Technology Data Exchange (ETDEWEB)

Moraga Contreras, P.; Grande Andrade, Z.; Castillo Ron, E.

2016-07-01

The paper discusses the advantages and shortcomings of alternate double single track (ADST) lines with respect to double track lines for high speed lines. ADST lines consists of sequences of double and single track segments optimally selected in order to reduce the construction and maintenance costs of railway lines and to optimize the timetables used to satisfy a given demand. The single tracks are selected to coincide with expensive segments (tunnels and viaducts) and the double tracks are chosen to coincide with flat areas and only where they are necessary. At the same time, departure times are adjusted for trains to cross at the cheap double track segments. This alternative can be used for new lines and also for existing conventional lines where some new tracks are to be constructed to reduce travel time (increase speed). The ADST proposal is illustrated with some examples of both types (new lines and where conventional lines exist), including the Palencia-Santander, the Santiago-Valparaíso-Viña del Mar and the Dublin-Belfast lines, where very important reductions (90 %) are obtained, especially where a railway infrastructure already exist. (Author)

Double photoionization of helium: A new correlated double continuum wave function

Energy Technology Data Exchange (ETDEWEB)

Macri, P.A.; Kornberg, M.A.; Miraglia, J.E. [Consejo Nacional de Investigaciones Cientificas y Tecnicas, Buenos Aires (Argentina). Inst. de Astron. y Fisica del Espacio; Garibotti, C.R.; Gasaneo, G.; Colavecchia, F.D. [Centro Atomico Bariloche, Comision Nacional de Energia Atomica, 8400 S.C. de Bariloche, Rio Negro (Argentina)

1997-10-01

In this work we discuss the failures and goodness of using the product of two and three Coulomb waves to represent the double-continuum wave function of two electrons in the field of an ion. Furthermore, we present a new wave function for the double continuum, which takes into account the non-diagonal part of the kinetic energy. It satisfies the correct boundary conditions for large particle separations, and treats the electronic interaction in a more realistic way than the previously enunciated models. (orig.). 14 refs.

Aspects of the doubled worldsheet

Energy Technology Data Exchange (ETDEWEB)

Driezen, Sibylle; Sevrin, Alexander; Thompson, Daniel C. [Theoretische Natuurkunde, Vrije Universiteit Brussel and The International Solvay Institutes,Pleinlaan 2, B-1050 Brussels (Belgium)

2016-12-16

We clarify the relation between various approaches to the manifestly T-duality symmetric string. We explain in detail how the PST covariant doubled string arises from an unusual gauge fixing. We pay careful attention to the role of “spectator” fields in this process and also show how the T-duality invariant doubled dilaton emerges naturally. We extend these ideas to non-Abelian T-duality and show they give rise to the duality invariant formalism based on the semi-Abelian Drinfeld Double. We then develop the N=(0,1) supersymmetric duality invariant formalism.

The topology of Double Field Theory

Science.gov (United States)

Hassler, Falk

2018-04-01

We describe the doubled space of Double Field Theory as a group manifold G with an arbitrary generalized metric. Local information from the latter is not relevant to our discussion and so G only captures the topology of the doubled space. Strong Constraint solutions are maximal isotropic submanifold M in G. We construct them and their Generalized Geometry in Double Field Theory on Group Manifolds. In general, G admits different physical subspace M which are Poisson-Lie T-dual to each other. By studying two examples, we reproduce the topology changes induced by T-duality with non-trivial H-flux which were discussed by Bouwknegt, Evslin and Mathai [1].

Aristotle and Double Effect

DEFF Research Database (Denmark)

Di Nucci, Ezio

2014-01-01

There are some interesting similarities between Aristotle’s ‘mixed actions’ in Book III of the Nicomachean Ethics and the actions often thought to be justifiable with the Doctrine of Double Effect. Here I analyse these similarities by comparing Aristotle’s examples of mixed actions with standard...... cases from the literature on double effect such as, amongst others, strategic bombing, the trolley problem, and craniotomy. I find that, despite some common features such as the dilemmatic structure and the inevitability of a bad effect, Aristotle’s mixed actions do not count as cases justifiable...... through application of the Doctrine of Double Effect because they fail to meet the crucial necessary condition of the Doctrine according to which the bad effect can only be a merely foreseen side- effect and not an intended means....

Greenhouse effect in double-skin facade

Energy Technology Data Exchange (ETDEWEB)

Gratia, E.; Herde, A. de [Universite Catholique de Louvain, Architecture et Climat, Louvain-La-Neuve (Belgium)

2007-02-15

In these last years, a great deal of interest has been devoted to double-skin facades due to the advantages claimed by this technology (in terms of energy saving in the cold season, high-tech image, protection from external noise and wind loads). One of the great characteristics of the double-skin facade is the greenhouse effect. We identify the factors that influence the greenhouse effect. The identified parameters are solar radiation level, orientation and shading devices use, opaque wall/window proportion of the interior facade, wind speed, colour of shading devices and of interior facade, depth of the cavity of the double-skin, glazing type in the interior facade and openings in the double-skin. We analyze the impact of these parameters on the mean air temperature evolution in the cavity. After that analyse, the article answers the question: is greenhouse effect favourable? The answer is moderate according to the double-skin orientation. (author)

Observing and Measuring Visual Double Stars

CERN Document Server

2013-01-01

In these days of high-precision astrometric satellites, tremendous contributions to the science of astrometry are being made by amateur astronomers around the globe. This second edition of Observing and Measuring Visual Double Stars contains a significant amount of completely new material inspired by the work done by observers - particularly in the USA - since the first edition was published. Fifteen skilled and experienced astronomers have contributed chapters on their own specialization in the various fields. These include how to use the Internet to carry out precise astronomical measurement, an excellent guide to sketching double stars, and information on how to image double stars of unequal brightness. This new edition is the definitive book for those who are serious about this fascinating aspect of astronomy! Author Bob Argyle has been observing visual double stars for more than 40 years, some with the help of the world's biggest refractors, and has been director of the Webb Society Double Star Se...

Double Chooz experiment

International Nuclear Information System (INIS)

Palomares, C.

2009-01-01

Double Chooz will use two identical detectors at different distances from the Chooz nuclear power station to search for a non-vanishing value of θ 13 , and, hopefully, to open the way to experiments aspiring to discover CP violation in the leptonic sector. The far detector is expected to be operative by the end of 2009. Installation of the near detector will occur in 2010. Double Chooz has the capacity to exclude sin 2 (2θ 13 ) 31 2 = 2.5 x 10 -3 eV 2 with three years of data running both near and far detectors. (author)

Double Layer Dynamics in a Collisionless Magnetoplasma

DEFF Research Database (Denmark)

Iizuka, S.; Michelsen, Poul; Juul Rasmussen, Jens

and propagation of a double layer. The period of the oscillations is determined by the propagation length of the double layer. The current is limited during the propagation of the double layer by a growing negative potential barrier formed on the low potential tail. Similar phenomena appear when a potential......An experimental investigation of the dynamics of double layers is presented. The experiments are performed in a Q-machine plasma and the double layers are generated by applying a positive step potential to a cold collector plate terminating the plasma column. The double layer is created...... at the grounded plasma source just after the pulse is applied and it propagates towards the collector with a speed around the ion acoustic speed. When the collector is biased positively, large oscillations are obserced in the plasma current. These oscillations are found to be related to a recurring formation...

International and domestic aspects of double taxation

OpenAIRE

Murgáčová, Miroslava

2010-01-01

International and local aspects of double taxation Abstract The purpose of my thesis is to analyze international double taxation taking into account both local legislation and international aspects. Double taxation is the situation, where the same income (or capital) is subject to the same tax more than once. Mostly, the international double taxation appears when the state of the source of income implies taxes on the income of the non-residents and the state of residence of the income receive...

Preparation of uranium ingots from double fluorides; Elaboration de lingots d'uranium a partir de fluorures doubles

Energy Technology Data Exchange (ETDEWEB)

Le Boulbin, E [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1967-05-15

A simple method has been developed for the preparation of uranium double fluorides and has given a new impetus to the study of the reduction of these compounds with a view to obtaining very pure uranium ingots. This reduction can be carried out using calcium or magnesium as the reducing agent, this latter metal being very interesting from the practical point of view. A comparative study of the heat balances of the reduction processes for the double fluorides and for uranium tetrafluoride has shown that reduction of the double fluorides is possible. The exact experimental conditions for these reductions have been determined. Our study has shown in particular that the reduction of the double salt UF{sub 4}, CaF{sub 2} by magnesium leads to the production of small (20 to 500 g) samples of high-purity uranium with a yield of 99 per cent. (author) [French] La mise au point d'une methode simple de preparation de fluorures doubles d'uranium a remis a l'ordre du jour la reduction de ces composes en vue d'obtenir des lingots d'uranium tres pur. Cette reduction peut etre conduite en utilisant du calcium ou du magnesium comme reducteur, ce dernier metal etant tres interessant du point de vue pratique. Une etude comparative des bilans thermiques des reductions des fluorures doubles et du tetrafluorure d'uranium a montre que la reduction des fluorures doubles etait possible. Les conditions experimentales precises de ces reductions ont ete determinees. Notre etude a montre, en particulier, que la reduction du sel double UF{sub 4}, F{sub 2}Ca par le magnesium permet d'obtenir sur des petites quantites de 20 a 500 g, de l'uranium de haute purete avec un rendement de 99 pour cent. (auteur)

A double layer review

International Nuclear Information System (INIS)

Block, L.P.

1977-06-01

A review of the main results on electrostatic double layers (sometimes called space charge layers or sheaths) obtained from theory, and laboratory and space experiments up to the spring of 1977 is given. By means of barium jets and satellite probes, double layers have now been found at the altitudes, earlier predicted theoretically. The general potential distribution above the auroral zone, suggested by inverted V-events and electric field reversals, is corroborated. (author)

Analytical threshold voltage modeling of ion-implanted strained-Si double-material double-gate (DMDG) MOSFETs

Science.gov (United States)

Goel, Ekta; Singh, Balraj; Kumar, Sanjay; Singh, Kunal; Jit, Satyabrata

2017-04-01

Two dimensional threshold voltage model of ion-implanted strained-Si double-material double-gate MOSFETs has been done based on the solution of two dimensional Poisson's equation in the channel region using the parabolic approximation method. Novelty of the proposed device structure lies in the amalgamation of the advantages of both the strained-Si channel and double-material double-gate structure with a vertical Gaussian-like doping profile. The effects of different device parameters (such as device channel length, gate length ratios, germanium mole fraction) and doping parameters (such as projected range, straggle parameter) on threshold voltage of the proposed structure have been investigated. It is observed that the subthreshold performance of the device can be improved by simply controlling the doping parameters while maintaining other device parameters constant. The modeling results show a good agreement with the numerical simulation data obtained by using ATLAS™, a 2D device simulator from SILVACO.

Element nodes of sports equipment double back flip factions and double back flip hunched performed gymnast in floor exercise

Directory of Open Access Journals (Sweden)

V.A. Potop

2014-07-01

Full Text Available Purpose: to identify the node elements of sports equipment double back somersault tuck and double back flip bent. To compare the two types of nodes for double somersault. Material : the study involved eight gymnasts (age 12 - 14 years. All finalists in the competition floor exercise - reserve team Romania. The method of video - computer research and method of postural orientation movements. Results : identified nodal elements of sports equipment double back somersault tuck and double back flip bent. In the preparatory phase of motor actions - launcher body posture for reaching is repulsive to flip. In the phase of basic motor action - animation body postures (double back somersault tuck and bent (bent double back flip. Exercises are performed on the ascending and descending parts of the flight path of the demonstration of individual maximum lift height common center of mass. In the final phase of motor actions - final body posture - steady landing. Conclusions : indicators of key elements of sports equipment acrobatic exercises contain new scientific facts kinematic and dynamic structures of motor actions. They are necessary for the development of modern training programs acrobatic exercises in step specialized base preparation.

Double Chooz

Energy Technology Data Exchange (ETDEWEB)

Buck, Christian [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany)

2006-05-15

The goal of the Double Chooz reactor neutrino experiment is to search for the neutrino mixing parameter {theta}{sub 13}. Double Chooz will use two identical detectors at 150 m and 1.05 km distance from the reactor cores. The near detector is used to monitor the reactor {nu}-bar {sub e} flux while the second is dedicated to the search for a deviation from the expected (1/distance){sup 2} behavior. This two detector concept will allow a relative normalization systematic error of ca. 0.6 %. The expected sensitivity for sin{sup 2}2{theta}{sub 13} is then in the range 0.02 - 0.03 after three years of data taking. The antineutrinos will be detected in a liquid scintillator through the capture on protons followed by a gamma cascade, produced by the neutron capture on Gd.

Psychological determinants of physical activity across the life course: A "DEterminants of DIet and Physical ACtivity" (DEDIPAC umbrella systematic literature review.

Directory of Open Access Journals (Sweden)

Cristina Cortis

Full Text Available Low levels of physical activity (PA are reported to contribute to the occurrence of non-communicable diseases over the life course. Although psychological factors have been identified as an important category concerning PA behavior, knowledge on psychological determinants of PA is still inconclusive. Therefore, the aim of this umbrella systematic literature review (SLR was to summarize and synthesize the scientific evidence on psychological determinants of PA behavior across the life course. A systematic online search was conducted on MEDLINE, ISI Web of Science, Scopus, and SPORTDiscus databases. The search was limited to studies published in English from January 2004 to April 2016. SLRs and meta-analyses (MAs of observational studies investigating the association of psychological variables and PA were considered eligible. Extracted data were evaluated based on importance of determinants, strength of evidence, and methodological quality. The full protocol is available from PROSPERO (Record ID: CRD42015010616. Twenty reviews (14 SLRs and 6 MAs, mostly of moderate methodological quality, were found eligible. Convincing evidence was found for self-efficacy (positive association with PA in children and adolescents, and stress (negative association with PA regardless of age. Most of the evidence revealing an association between psychological determinants and PA is probable and limited, mainly due to differences in the definition of PA and of psychological determinants across reviews. Thus, scholars are urged to reach a consensus on clear definitions of relevant psychological determinants of PA, subsuming cultural biases and allowing the possibility to obtain clear interpretations and generalizability of findings. Finally, most psychological determinants should be considered within a larger framework of other multi-level determinants that may interact or mediate some of the effects.

Torus-doubling process via strange nonchaotic attractors

International Nuclear Information System (INIS)

Mitsui, Takahito; Uenohara, Seiji; Morie, Takashi; Horio, Yoshihiko; Aihara, Kazuyuki

2012-01-01

Torus-doubling bifurcations typically occur only a finite number of times. It has been assumed that torus-doubling bifurcations in quasiperiodically forced systems are interrupted by the appearance of strange nonchaotic attractors (SNAs). In the present Letter, we study a quasiperiodically forced noninvertible map and report the occurrence of a torus-doubling process via SNAs. The mechanism of this process is numerically clarified. Furthermore, this process is experimentally demonstrated in a switched-capacitor integrated circuit. -- Highlights: ► We report the occurrence of a torus-doubling process via strange nonchaotic attractors (SNAs). ► The process consists of the gradual fractalization of a torus and the Heagy–Hammel transition. ► The torus-doubling process via SNAs is also experimentally demonstrated in an electronic circuit.

Gauge symmetry, T-duality and doubled geometry

International Nuclear Information System (INIS)

Hull, C.M.

2007-11-01

String compactifications with T-duality twists are revisited and the gauge algebra of the dimensionally reduced theories calculated. These reductions can be viewed as string theory on T-fold backgrounds, and can be formulated in a 'doubled space' in which each circle is supplemented by a T-dual circle to construct a geometry which is a doubled torus bundle over a circle. We discuss a conjectured extension to include T-duality on the base circle, and propose the introduction of a dual base coordinate, to give a doubled space which is locally the group manifold of the gauge group. Special cases include those in which the doubled group is a Drinfel'd double. This gives a framework to discuss backgrounds that are not even locally geometric. (orig.)

The International Double Taxation – causes and avoidance

Directory of Open Access Journals (Sweden)

Nicoleta Barbuta-Misu

2009-10-01

Full Text Available The politics and tax legislation being a manifestation of strict sovereignty of the State, the phenomenon of double taxation occursfrequently representing a difficult poison for the foreign trade activity, especially hindering investments abroad, technology transfer or proliferationoutside of the state of the companies’ branches. Therefore, international legal double taxation, by the repeated taxation of the income, it is anobstacle to the development of economic relations between states, reducing the revenue of the international operators and their interests in makinginvestment abroad. This paper presents the main causes that determine double taxation, its forms, i.e. the economic double taxation and theinternational legal double taxation, the need for eliminating the double taxation and avoidance methods.

26 CFR 509.120 - Double taxation claims.

Science.gov (United States)

2010-04-01

... 26 Internal Revenue 19 2010-04-01 2010-04-01 false Double taxation claims. 509.120 Section 509.120... CONVENTIONS SWITZERLAND General Income Tax § 509.120 Double taxation claims. (a) General. Under Article XVII... United States or Switzerland has resulted, or will result, in double taxation contrary to the provisions...

Fully double-logarithm-resummed cross sections

International Nuclear Information System (INIS)

Albino, S.; Bolzoni, P.; Kniehl, B.A.; Kotikov, A.

2011-01-01

We calculate the complete double logarithmic contribution to cross sections for semi-inclusive hadron production in the modified minimal-subtraction (MS-bar) scheme by applying dimensional regularization to the double logarithm approximation. The full double logarithmic contribution to the coefficient functions for inclusive hadron production in e + e - annihilation is obtained in this scheme for the first time. Our result agrees with all fixed order results in the literature, which extend to next-to-next-to-leading order.

Double-helix stellarator

International Nuclear Information System (INIS)

Moroz, P.E.

1997-09-01

A new stellarator configuration, the Double-Helix Stellarator (DHS), is introduced. This novel configuration features a double-helix center post as the only helical element of the stellarator coil system. The DHS configuration has many unique characteristics. One of them is the extreme low plasma aspect ratio, A ∼ 1--1.2. Other advantages include a high enclosed volume, appreciable rotational transform, and a possibility of extreme-high-β MHD equilibria. Moreover, the DHS features improved transport characteristics caused by the absence of the magnetic field ripple on the outboard of the torus. Compactness, simplicity and modularity of the coil system add to the DHS advantages for fusion applications

Etiological aspects of double monsters.

Science.gov (United States)

Jaschevatzky, O E; Goldman, B; Kampf, D; Wexler, H; Grünstein, S

1980-06-01

Four cases of double monsters are reported, including a rare case of craniofacial duplication (diprosopus). Based on the findings observed, etiological factors of these malformations are discussed. We suggest that exogenous (environmental) factors such as habits, way of life or religious practices of certain populations can influence the development of double monsters.

Gauge symmetry, T-duality and doubled geometry

Energy Technology Data Exchange (ETDEWEB)

Hull, C.M. [Imperial College London (United Kingdom). Inst. for Mathematical Sciences]|[Imperial College London (United Kingdom). Blackett Laboratory; Reid-Edwards, R.A. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik]|[Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

2007-11-15

String compactifications with T-duality twists are revisited and the gauge algebra of the dimensionally reduced theories calculated. These reductions can be viewed as string theory on T-fold backgrounds, and can be formulated in a 'doubled space' in which each circle is supplemented by a T-dual circle to construct a geometry which is a doubled torus bundle over a circle. We discuss a conjectured extension to include T-duality on the base circle, and propose the introduction of a dual base coordinate, to give a doubled space which is locally the group manifold of the gauge group. Special cases include those in which the doubled group is a Drinfel'd double. This gives a framework to discuss backgrounds that are not even locally geometric. (orig.)

Instability limits for spontaneous double layer formation

International Nuclear Information System (INIS)

Carr, J. Jr.; Galante, M. E.; McCarren, D.; Scime, E. E.; Sears, S.; VanDervort, R. W.; Magee, R. M.; Reynolds, E.

2013-01-01

We present time-resolved measurements that demonstrate that large amplitude electrostatic instabilities appear in pulsed, expanding helicon plasmas at the same time as particularly strong double layers appear in the expansion region. A significant cross-correlation between the electrostatic fluctuations and fluctuations in the number of ions accelerated by the double layer electric field is observed. No correlation is observed between the electrostatic fluctuations and ions that have not passed through the double layer. These measurements confirm that the simultaneous appearance of the electrostatic fluctuations and the double layer is not simple coincidence. In fact, the accelerated ion population is responsible for the growth of the instability. The double layer strength, and therefore, the velocity of the accelerated ions, is limited by the appearance of the electrostatic instability

Theoretical aspects of double beta decay

International Nuclear Information System (INIS)

Haxton, W.C.

1984-01-01

Considerable effort has been expended recently in theoretical studies of double beta decay. Much of this work has focussed on the constraints this process places on gauge theories of the weak interaction, in general, and on the neutrino mass matrix, in particular. In addition, interesting nuclear structure questions have arisen in studies of double beta decay matrix elements. After briefly reviewing the theory of double beta decay, some of the progress that has been made in these areas is summarized. 25 references

Monocular Elevation Deficiency - Double Elevator Palsy

Science.gov (United States)

... Español Condiciones Chinese Conditions Monocular Elevation Deficiency/ Double Elevator Palsy En Español Read in Chinese What is monocular elevation deficiency (Double Elevator Palsy)? Monocular Elevation Deficiency, also known by the ...

THE EFFICIENCY OF TENNIS DOUBLES SCORING SYSTEMS

Directory of Open Access Journals (Sweden)

Geoff Pollard

2010-09-01

Full Text Available In this paper a family of scoring systems for tennis doubles for testing the hypothesis that pair A is better than pair B versus the alternative hypothesis that pair B is better than A, is established. This family or benchmark of scoring systems can be used as a benchmark against which the efficiency of any doubles scoring system can be assessed. Thus, the formula for the efficiency of any doubles scoring system is derived. As in tennis singles, one scoring system based on the play-the-loser structure is shown to be more efficient than the benchmark systems. An expression for the relative efficiency of two doubles scoring systems is derived. Thus, the relative efficiency of the various scoring systems presently used in doubles can be assessed. The methods of this paper can be extended to a match between two teams of 2, 4, 8, …doubles pairs, so that it is possible to establish a measure for the relative efficiency of the various systems used for tennis contests between teams of players.

Clinical Significance of "Double-hit" and "Double-protein" expression in Primary Gastric B-cell Lymphomas.

Science.gov (United States)

He, Miaoxia; Chen, Keting; Li, Suhong; Zhang, Shimin; Zheng, Jianming; Hu, Xiaoxia; Gao, Lei; Chen, Jie; Song, Xianmin; Zhang, Weiping; Wang, Jianmin; Yang, Jianmin

2016-01-01

Primary gastric B-cell lymphoma is the second most common malignancy of the stomach. There are many controversial issues about its diagnosis, treatment and clinical management. "Double-hit" and "double-protein" involving gene rearrangement and protein expression of c-Myc and bcl2/bcl6 are the most used terms to describe DLBCL poor prognostic factors in recent years. However, very little is known about the role of these prognostic factors in primary gastric B-cell lymphomas. This study aims to obtain a molecular pathology prognostic model of gastric B-cell lymphoma for clinical stratified management by evaluating how the "double-hit" and "double-protein" in tumor cells as well as microenvironmental reaction of tumor stromal tissue affect clinical outcome in primary gastric B-cell lymphomas. Data and tissues of 188 cases diagnosed with gastric B-cell lymphomas were used in this study. Tumor tissue microarray (TMA) of formalin fixed and paraffin embedded (FFPE) tissues was constructed for fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) analysis with a serial of biomarkers containing MYC, BCL2, BCL6, CD31, SPARC, CD10, MUM1 and Ki-67. Modeled period analysis was used to estimate 3-year and 5-year overall survival (OS) and disease-free survival (DFS) distributions. There was no definite "double-hit" case though the gene rearrangement of c-Myc (5.9%), bcl2 (0.1%) and bcl6 (7.4%) was found in gastric B-cell lymphomas. The gene amplification or copy gains of c-Myc (10.1%), bcl-2 (17.0%) and bcl-6 (0.9%) were present in these lymphomas. There were 12 cases of the lymphomas with the "double-protein" expression of MYC and BCL2/BCL6. All patients with "double-protein" gastric B-cell lymphomas had poor outcome compared with those without. More importantly, "MYC-BCL2-BCL6" negative group of gastric B-cell lymphoma patients had favorable clinical outcome regardless clinical stage, pathological types and therapeutic modalities. And the similar better

Three Dimensional Double Layers in Magnetized Plasmas

DEFF Research Database (Denmark)

Jovanovic, D.; Lynov, Jens-Peter; Michelsen, Poul

1982-01-01

Experimental results are presented which demonstrate the formation of fully three dimensional double layers in a magnetized plasma. The measurements are performed in a magnetized stationary plasma column with radius 1.5 cm. Double layers are produced by introducing an electron beam with radius 0.......4 cm along the magnetic field from one end of the column. The voltage drop across the double layer is found to be determined by the energy of the incoming electron beam. In general we find that the width of the double layer along the external magnetic field is determined by plasma density and beam...

Double contrast barium meal and acetylcysteine

International Nuclear Information System (INIS)

Kinnunen, J.; Pietilae, J.; Ahovuo, J.; Mankinen, P.; Tervahartiala, P.

1989-01-01

In a prospective double blind study, acetylcysteine, a local and systemic respiratory tract mucolytic agent, or a placebo, were given to 100 patients prior to a double contrast barium meal to decrease the gastric mucus viscosity and to make the mucus layer thinner, in order to permit barium to outline the furrows surrounding the areae gastricae instead of the overlying thick mucus. However, acetylcysteine failed to improve either visualization of the areae gastricae or the general quality of the double contrast barium meal. (orig.)

Positivity bounds on double parton distributions

International Nuclear Information System (INIS)

Diehl, Markus; Kasemets, Tomas

2013-03-01

Double hard scattering in proton-proton collisions is described in terms of double parton distributions. We derive bounds on these distributions that follow from their interpretation as probability densities, taking into account all possible spin correlations between two partons in an unpolarized proton. These bounds constrain the size of the polarized distributions and can for instance be used to set upper limits on the effects of spin correlations in double hard scattering. We show that the bounds are stable under leading-order DGLAP evolution to higher scales.

Laser alignment measurement model with double beam

Science.gov (United States)

Mo, Changtao; Zhang, Lili; Hou, Xianglin; Wang, Ming; Lv, Jia; Du, Xin; He, Ping

2012-10-01

Double LD-Double PSD schedule.employ a symmetric structure and there are a laser and a PSD receiver on each axis. The Double LD-Double PSD is used, and the rectangular coordinate system is set up by use of the relationship of arbitrary two points coordinates, and then the parameter formula is deduced by the knowledge of solid geometry. Using the data acquisition system and the data processing model of laser alignment meter with double laser beam and two detector , basing on the installation parameter of the computer, we can have the state parameter between the two shafts by more complicated calculation and correction. The correcting data of the four under chassis of the adjusted apparatus moving on the level and the vertical plane can be calculated using the computer. This will instruct us to move the apparatus to align the shafts.

Double-polarizating scanning radiometer

International Nuclear Information System (INIS)

Mishev, D.N.; Nazyrski, T.G.

1986-01-01

The double-polarizating single-channel scanning radiometer comprises the following serial connected parts: a scanning double-polarizating aerial, a block for polarization separation, a radiometer receiver, an analog-to-digit converter and an information flow forming block. The low frequency input of the radiometer receiver is connected with a control block, which is also connected with a first bus of a microprocessor, the second bus of which is connected with the A-D converter. The control input of the scanning double-polarizating aerial is connected with the first microprocessor bus. The control inputs of the block for polarization separation are linked by an electronic switch with the output of the forming block, the input of which is connected to the first input of the control block. The control inputs of the block for polarization separation are connected with the second and the third input of the information flow forming block. 2 cls

Energy-efficient adjustable speed double inverter-fed woundrotor ...

African Journals Online (AJOL)

Energy-efficient adjustable speed double inverter-fed woundrotor induction motor ... at speeds up to double rated without the magnetic flux reducing is presented. ... Keywords: power, double-fed wound-rotor induction motor drive, steel and ...

Half Double Methodology – Leading projects to impact in half the time with double the impact

DEFF Research Database (Denmark)

Ehlers, Michael; Svejvig, Per

this presentation to learn about the three core elements of the half-double methodology so that you can lead your projects to double the impact in half the time. Objectives: Summarize the half-double methodology and core elements of impact, flow, and leadership; explain how PMI’s project management tools can......Despite developments in agile methodologies over the last 20 years, the potential for optimization in projects is still significant. Current research shows that there are methodologies that can be used to reduce lead time and increase value creation of projects by 30% or more. Join...

Early results of transcatheter closure of patent ductus arteriosus: retrospective study of 61 patients

International Nuclear Information System (INIS)

Beg, A.M.; Younas, M.; Chaudary, A.T.

2013-01-01

Patent ductus arteriosus (PDA) accounts for 6 - 11% of all congenital heart defects. Complications of PDA include congestive heart failure, repeated chest infections, pulmonary hypertension, and an increased risk of infective endocarditis. Transcatheter closure of PDA has largely replaced surgical ligation in different age groups. Currently, surgical intervention is restricted to premature babies or small infants with large symptomatic PDA, cases with unfavorable duct anatomy, and whenever the cost of the closure devices is unaffordable. PDA was the first example of congenital heart dis-ease to be treated by transcatheter closure, which becomes an established form of treatment for the majority of patients with PDA and as a safe alternative to surgery. The per-cutaneous technique was first described by Porstmanur et al., since then various devices such as Rashkind PDA umbrella, button device, PDA coils and most recently the Amplatzer duct occluder (ADO) have been introduced. The ADO device was designed to provide the most desirable characteristics for a percutaneous closure device that can be used in most if not all patients with PDA. These include user - friendly delivery system, high complete closure rate, small delivery system (allowing its use in small infants), trans-venous delivery route, ability to adapt to various PDA sizes and types, and the ability to retrieve or reposition the device prior to release from a secure delivery system. Common complications of trans-catheter closure of PDA include residual shunt, left pulmonary artery (LPA) obstruction, protrusion of the device into the aorta, and embolization of the device. Incidence of complications increases with certain types and large size ducts, and with the use of multiple coils for occlusion. There are only a few reports correlating out-come and complications with the learning curve and experience. In this study, we are reporting our initial experience with PDA closure using Amplatzer duct occluder (ADO

Overlay metrology for double patterning processes

Science.gov (United States)

Leray, Philippe; Cheng, Shaunee; Laidler, David; Kandel, Daniel; Adel, Mike; Dinu, Berta; Polli, Marco; Vasconi, Mauro; Salski, Bartlomiej

2009-03-01

The double patterning (DPT) process is foreseen by the industry to be the main solution for the 32 nm technology node and even beyond. Meanwhile process compatibility has to be maintained and the performance of overlay metrology has to improve. To achieve this for Image Based Overlay (IBO), usually the optics of overlay tools are improved. It was also demonstrated that these requirements are achievable with a Diffraction Based Overlay (DBO) technique named SCOLTM [1]. In addition, we believe that overlay measurements with respect to a reference grid are required to achieve the required overlay control [2]. This induces at least a three-fold increase in the number of measurements (2 for double patterned layers to the reference grid and 1 between the double patterned layers). The requirements of process compatibility, enhanced performance and large number of measurements make the choice of overlay metrology for DPT very challenging. In this work we use different flavors of the standard overlay metrology technique (IBO) as well as the new technique (SCOL) to address these three requirements. The compatibility of the corresponding overlay targets with double patterning processes (Litho-Etch-Litho-Etch (LELE); Litho-Freeze-Litho-Etch (LFLE), Spacer defined) is tested. The process impact on different target types is discussed (CD bias LELE, Contrast for LFLE). We compare the standard imaging overlay metrology with non-standard imaging techniques dedicated to double patterning processes (multilayer imaging targets allowing one overlay target instead of three, very small imaging targets). In addition to standard designs already discussed [1], we investigate SCOL target designs specific to double patterning processes. The feedback to the scanner is determined using the different techniques. The final overlay results obtained are compared accordingly. We conclude with the pros and cons of each technique and suggest the optimal metrology strategy for overlay control in double

Bifurcation structure of successive torus doubling

International Nuclear Information System (INIS)

Sekikawa, Munehisa; Inaba, Naohiko; Yoshinaga, Tetsuya; Tsubouchi, Takashi

2006-01-01

The authors discuss the 'embryology' of successive torus doubling via the bifurcation theory, and assert that the coupled map of a logistic map and a circle map has a structure capable of generating infinite number of torus doublings

Optimal operation of a south double-skin facade

Energy Technology Data Exchange (ETDEWEB)

Gratia, E.; De Herde, A. [Universite Catholique de Louvain (Belgium). Architecture et Climat

2004-01-01

There is an increasing demand for higher quality office buildings. Occupants and developers of office buildings ask for a healthy and stimulating working environment. Double-skin facades are appropriate when buildings are subject to great external noise and wind loads. A further area of application is in rehabilitation work, when existing facades cannot be renewed, or where this is not desirable. Double-skin facades have a special esthetic of their own, and this can be exploited architecturally to great advantage. However there are still relatively few buildings in which double-skin facades have actually been realized, and there is still too little experience of their behaviour in operation. In this matter, we choose to study a multi-storey double-skin facades behaviour. Simulations were realized with TAS software on the building proposed in the frame of the subtask A of the Task 27 (performance of solar facade components) of the International Energy Agency. Simulations were performed on the chosen building with and without double-skin facades. We decide to study eight types of days; and we analyze the double-skin facade behaviour for various operations. The thermal behaviours of the building with and without double-skin are compared. The study of these eight cases showed the importance of the dynamic use of the double-skin. The operation of this one must be obligatorily related to the climatic conditions as well external as interior and a bad operation of the double-skin could lead to catastrophic results. (author)

The Maui International Double Star Conference

Science.gov (United States)

Genet, Russell

2013-04-01

A three-day double star conference in February, 2013, covered double star observations from simple eyepiece astrometry of wide binaries, with orbital periods of centuries, to amplitude interferometry of binaries with periods measured in days or even hours. A wide range of participants, from students and amateurs to professionals shared their perspectives in panel discussions. This was the first conference of the newly-formed International Association of Double Star Observers (IADSO). PDFs of 22 of the talks and YouTube links to 23 of the talks and panels are available at www.IADSO.org.

Double layer dynamics in a collisionless magnetoplasma

International Nuclear Information System (INIS)

Iizuka, Satoru; Michelsen, P.; Rasmussen, J.J.; Schrittwieser, R.; Hatakeyama, Rikizo; Saeki, Koichi; Sato, Noriyoshi.

1985-01-01

Investigations of double layer dynamics are performed in a Q-machine plasma by applying a positive step potential to a cold end-plate collector. The double layer created at the grounded plasma source just after the pulse is applied propagates towards the collector with the plasma flow speed. Large oscillations occur in the plasma current which is related to a recurring formation and propagation of the double layer. The current is limited during the propagation by a growing negative potential dip formed on the low-potential tail. Similar phenomena appear on the low-potential tail of the stationary double layer formed by applying a potential difference between two plasma sources. (author)

Double layer dynamics in a collisionless magnetoplasma

DEFF Research Database (Denmark)

Iizuka, S.; Michelsen, Poul; Juul Rasmussen, Jens

1985-01-01

Investigations of double layer dynamics are performed in a Q-machine plasma by applying a positive step potential to a cold end-plate collector. The double layer created at the grounded plasma source just after the pulse is applied propagates towards the collector with the plasma flow speed. Large...... oscillations occur in the plasma current which is related to a recurring formation and propagation of the double layer. The current is limited during the propagation by a growing negative potential dip formed on the low-potential tail. Similar phenomena appear on the low-potential tail of the stationary double...... layer formed by applying a potential difference between two plasma sources...

EFFECTIVENESS OF DOUBLE WASH SWIM-UP VERSUS DOUBLE DENSITY GRADIENT SWIM-UP TECHNIQUE OF SPERM PREPARATION IN IN VITRO FERTILISATION

Directory of Open Access Journals (Sweden)

Srinivas Sangisapu

2017-10-01

Full Text Available BACKGROUND Recovery of optimum number of good quality of spermatozoa is an important component of In Vitro Fertilisation (IVF. This is achieved by sperm preparation methods involving separation and recovery of capacitated sperms. Double Wash Swim-up (DWSU and Double Density Gradient Swim-up (DDGSU are two most accepted methods. Cochrane systematic review (2007 finds no clear benefit of one method over the other in Intrauterine Insemination (IUI. Systematic review on effectiveness of these preparations in IVF is lacking. Effectiveness is generally assessed in terms recovery rates of the sperms. Capability of successful fertilisation of good quality oocytes should ideally be the functional endpoint for evaluating effectiveness of sperm preparation methods. The aim of the study is to1. Compare the successful fertilisation rates of oocytes inseminated by semen preparation of Double Wash Swim-up (DWSU vis-a-vis by Double Density Gradient Swim-up (DDGSU method. 2. Evaluate the effectiveness of fertilisation of oocytes by Double Wash Swim-up method (DWSU vis-a-vis Double Density Gradient Swim-up (DDGSU method. MATERIALS AND METHODS A retrospective cohort study was conducted on infertile couples undergoing IVF from June 2014 to June 2017 at an ART Centre of a tertiary care hospital. The male partners were normozoospermic and female partners were normoresponsive to controlled ovarian stimulation and oocyte retrieval. RESULTS 70 male partners were subjected to double wash swim-up and 64 underwent double density gradient swim-up preparation. 1296 good quality oocytes were retrieved in their respective female partners. 452 (61% out of 742 oocytes were successfully fertilised after insemination by semen prepared by DWSU method. 378 (68% oocytes out of 554 were fertilised by insemination with semen prepared by DDGSU method. There seems to be strong association (RR=1.12 of fertilisation success with oocytes exposed to semen prepared by Double Density Gradient

John Deakin: Double Exposures

Directory of Open Access Journals (Sweden)

Paul Rousseau

2015-11-01

Full Text Available In this series of short films made by Jonathan Law, the art historian James Boaden, and the curator of The John Deakin Archive, Paul Rousseau, discuss the double-exposure images made by the photographer John Deakin (1912-1972 in the 1950s and 1960s. The films ask you, firstly, to look closely at the images being discussed. Each one begins with a sustained and intense shot of a single image before opening up to a wide-ranging discussion about Deakin, double exposures, and photography.

Double-plug seismic connector

International Nuclear Information System (INIS)

Annoot, I.R.

1984-01-01

The double-plug seismic electric connector comprises an elongated insulating body. A male connector plug is at one end of the body and a female connector plug is at the opposite end of the body. Each plug has a pair of male and female contacts. A pair of spaced axial conductors is embedded within the insulating body for interconnecting the opposite male and female contacts. The inner end of a double-wire cable is embedded within the insulating body and each wire inner end is connected to one of the conductors

Dynamical Aspects of Electrostatic Double Layers

DEFF Research Database (Denmark)

Raadu, M.A.; Juul Rasmussen, J.

1988-01-01

Electrostatic double layers have been proposed as an acceleration mechanism in solar flares and other astrophysical objects. They have been extensively studied in the laboratory and by means of computer simulations. The theory of steady-state double layers implies several existence criteria...

Double-outlet right ventricle revisited.

Science.gov (United States)

Ebadi, Ameneh; Spicer, Diane E; Backer, Carl L; Fricker, F Jay; Anderson, Robert H

2017-08-01

Double-outlet right ventricle is a form of ventriculoarterial connection. The definition formulated by the International Society for Nomenclature of Paediatric and Congenital Heart Disease is based on hearts with both arterial trunks supported in their greater part by a morphologically right ventricle. Bilateral infundibula and ventricular septal defects are highly debated criteria. This study examines the anatomic controversies surrounding double-outlet right ventricle. We show that hearts with double-outlet right ventricle can have atrioventricular-to-arterial valvular continuity. We emphasize the difference between the interventricular communication and the zone of deficient ventricular septation. The hearts examined were from the University of Florida in Gainesville; Johns Hopkins All Children's Hospital, St Petersburg, Fla; and Lurie Children's Hospital, Chicago, Ill. Each specimen had at least 75% of both arterial roots supported by the morphologically right ventricle, with a total of 100 hearts examined. The morphologic method was used to assess anatomic features, including arterial-atrioventricular valvular continuity, subarterial infundibular musculature, and the location of the hole between the ventricles. Most hearts had fibrous continuity between one of the arterial valves and an atrioventricular valve, with bilateral infundibula in 23%, and intact ventricular septum in 5%. Bilateral infundibula are not a defining feature of double-outlet right ventricle, representing only 23% of the specimens in our sample. The interventricular communication can have a posteroinferior muscular rim or extend to become perimembranous (58%). Double-outlet right ventricle can exist with an intact ventricular septum. Copyright © 2017 The American Association for Thoracic Surgery. All rights reserved.

Alignment in double capture processes

International Nuclear Information System (INIS)

Moretto-Capelle, P.; Benhenni, M.; Bordenave-Montesquieu, A.; Benoit-Cattin, P.; Gleizes, A.

1993-01-01

The electron spectra emitted when a double capture occurs in N 7+ +He and Ne 8+ +He systems at 10 qkeV collisional energy, allow us to determine the angular distributions of the 3 ell 3 ell ' lines through a special spectra fitting procedure which includes interferences between neighbouring states. It is found that the doubly excited states populated in double capture processes are generally aligned

Doubling in RSL and NGT: a pragmatic account

NARCIS (Netherlands)

Kimmelman, V.

2013-01-01

In this paper, doubling in Russian Sign Language and Sign Language of the Netherlands is discussed. In both sign languages different constituents (including verbs, nouns, adjectives, adverbs, and whole clauses) can be doubled. It is shown that doubling in both languages has common functions and

A double-gate double-feedback JFET charge-sensitive preamplifier

International Nuclear Information System (INIS)

Fazzi, A.

1996-01-01

A new charge-sensitive preamplifier (CSP) without a physical resistance in the feedback is presented. The input device has to be a double-gate JFET. In this new preamplifier configuration the feedback capacitor is continuously discharged by means of a second DC current feedback loop closed through the bottom gate of the input JFET. The top gate-channel junction works as usual in reverse bias, the bottom gate-channel is forward biased. A fraction of the current injected by the bottom gate reaches the top gate discharging the feedback capacitor. The n-channel double-gate JFET is considered from the viewpoint of the restoring action as a parasitic p-n-p ''transversal'' bipolar junction transistor. The new preamplifier is also suited for detectors operating at room temperature with leakage current which may vary with time. The DC behaviour and the dynamic behaviour of the circuit is analyzed and new measurements presented. (orig.)

Dynamics of vacuum-sealed, double-leaf partitions

Science.gov (United States)

Kavanaugh, Joshua Stephen

The goal of this research is to investigate the feasibility and potential effectiveness of using vacuum-sealed, double-leaf partitions for applications in noise control. Substantial work has been done previously on double-leaf partitions where the acoustics of the inner chamber and mechanical vibrations of structural supports are passively and actively controlled. The work presented here is unique in that the proposed system aims to eliminate the need for active acoustic control of transmitted acoustic energy by removing all the air between the two panels of the double partition. Therefore, the only remaining energy paths would be along the boundary and at the points where there are intermediate structural supports connecting the two panels. The eventual goal of the research is to develop a high-loss double-leaf partition that simplifies active control by removing the need for control of the air cavity and channeling all the energy into discrete structural paths. The work presented here is a first step towards the goal of designing a high-loss, actively-controlled double-leaf partition with an air-evacuated inner chamber. One experiment is conducted to investigate the effects of various levels of vacuum on the response of a double-leaf partition whose panels are mechanically coupled only at the boundary. Another experiment is conducted which investigates the effect of changing the stiffness of an intermediate support coupling the two panels of a double-leaf partition in which a vacuum has been applied to the inner cavity. The available equipment was able to maintain a 99% vacuum between the panels. Both experiments are accompanied by analytical models used to investigate the importance of various dynamic parameters. Results show that the vacuum-sealed system shows some potential for increased transmission loss, primarily by the changing the natural frequencies of the double-leaf partition.

Double γ decay in 90Zr

International Nuclear Information System (INIS)

Mucciolo, E.R.

1988-01-01

The double γ decay between θ + n - θ + i of 90 Zr was observed. The θ + n level was fed through the decay of 90 Sr. The experimental arrangement consisted of a double coincidence system between the two semiconductor detectors. (A.C.A.S.) [pt

Majorana neutrinos and double beta-decay

International Nuclear Information System (INIS)

Shchepkin, M.G.

1986-01-01

Problem, related to neutrino mass and lepton charge L conservation is briefly discussed. A possibility to experimentally test L conservation in different processes and to produce limitations for neutrino mass in double beta-decay processes is considered. Planned experiments on studying the double neutrinoless (2β) beta-decays and searching 2β(2ν)-decays, permitted by the conservation laws, are discussed. It is stressed, that comparison of the existing theoretical predictions of 2β(2ν)-decay probability with experimental results will make it possible to choose the most adequate approach to the calculation of double β-transition nuclear amplitudes

The double Brewster angle effect

Science.gov (United States)

Thirion-Lefevre, Laetitia; Guinvarc'h, Régis

2018-01-01

The Double Brewster angle effect (DBE) is an extension of the Brewster angle to double reflection on two orthogonal dielectric surfaces. It results from the combination of two pseudo-Brewster angles occurring in complementary incidence angles domains. It can be observed for a large range of incidence angles provided that double bounces mechanism is present. As a consequence of this effect, we show that the reflection coefficient at VV polarization can be at least 10 dB lower than the reflection coefficient at HH polarization over a wide range of incidence angle - typically from 20 to 70∘. It is experimentally demonstrated using a Synthetic Aperture Radar (SAR) image that this effect can be seen on buildings and forests. For large buildings, the difference can reach more than 20 dB. xml:lang="fr"

How I treat double-hit lymphoma.

Science.gov (United States)

Friedberg, Jonathan W

2017-08-03

The 2016 revision of the World Health Organization (WHO) classification for lymphoma has included a new category of lymphoma, separate from diffuse large B-cell lymphoma, termed high-grade B-cell lymphoma with translocations involving myc and bcl-2 or bcl-6 . These lymphomas, which occur in hit lymphomas (or triple-hit lymphomas if all 3 rearrangements are present). It is important to differentiate these lymphomas from the larger group of double-expressor lymphomas, which have increased expression of MYC and BCL-2 and/or BCL-6 by immunohistochemistry, by using variable cutoff percentages to define positivity. Patients with double-hit lymphomas have a poor prognosis when treated with standard chemoimmunotherapy and have increased risk of central nervous system involvement and progression. Double-hit lymphomas may arise as a consequence of the transformation of the underlying indolent lymphoma. There are no published prospective trials in double-hit lymphoma, however retrospective studies strongly suggest that aggressive induction regimens may confer a superior outcome. In this article, I review my approach to the evaluation and treatment of double-hit lymphoma, with an eye toward future clinical trials incorporating rational targeted agents into the therapeutic armamentarium. © 2017 by The American Society of Hematology.

DOUBLE TAXATION CONVENTIONS AND THEIR IMPLEMENTATION IN ROMANIA

OpenAIRE

Mihail ANTONESCU; Ligia ANTONESCU

2011-01-01

The need to conclude bilateral agreements on avoidance of double taxation is determined by the fact that national tax regulations differ from state to state. In the same time unilateral tax measures adopted by national law to avoid double taxation don’t correspond to tax legislation of all countries with which Romania has economic relations. To avoid double taxation, our country uses both the national rules and conventions for the avoidance of double taxation concluded with partner countrie...

A Weekend Workshop on Double Stars for Students

Science.gov (United States)

Brewer, Mark; Estrada, Chris; Estrada, Reed; Gillette, Sean

2016-01-01

A weekend double star workshop was held by Vanguard Preparatory for selected eighth grade students with the purpose of introducing them to astrometric observational science. The students were selected based on an essay provided by their language arts class. Collaboration with local visiting astronomers was established to provide telescopes equipped with an astrometric eyepiece, observational supervision, and expertise. During the workshop students learned how to determine the scale constant of an astrometric eyepiece, and the procedure for measuring separations and position angles of double stars. The students compared their data to past measurements reported in the Washington Double Star Catalog. Three goals were set for the student's outcome: 1) observe, record, and report observations of double stars, 2) write a scientific paper for publication in the Journal of Double Star Observations, and 3) present a PowerPoint presentation to their peers. This paper chronicles the planning, preparation, funding, and execution required to complete a double star workshop at a public middle school.

Alignment in double capture processes

Energy Technology Data Exchange (ETDEWEB)

Moretto-Capelle, P.; Benhenni, M.; Bordenave-Montesquieu, A.; Benoit-Cattin, P.; Gleizes, A. (IRSAMC, URA CNRS 770, Univ. Paul Sabatier, 118 rte de Narbonne, 31062 Toulouse Cedex (France))

1993-06-05

The electron spectra emitted when a double capture occurs in N[sup 7+]+He and Ne[sup 8+]+He systems at 10 qkeV collisional energy, allow us to determine the angular distributions of the 3[ell]3[ell] [prime] lines through a special spectra fitting procedure which includes interferences between neighbouring states. It is found that the doubly excited states populated in double capture processes are generally aligned.

Decades with four double triodes

International Nuclear Information System (INIS)

Wahl, R.

1952-01-01

Decades with four double triodes The described decade consists of four double triodes and four crystals germanium; which has the following characteristics: - Attack in negative impulses. - Sensitivity 12 volts ± 40 % for signals of 1 μs about. - Time of resolution 2,5 μs. - Voltage 250 v ± 40 %. - heating 6,3 v ± 40 %. - Tolerance on the values of the elements of installation 10%. (author) [fr

The International Double Taxation – Avoiding Methods

OpenAIRE

Nicoleta Barbuta-Misu

2009-01-01

The paper presents the main causes that determine double taxation, its forms, i.e. the economicdouble taxation and the international legal double taxation, the need for eliminating the double taxation andavoiding methods. In the presentation of the avoidance methods have been used practical examples forcomparison of the tax advantages for income beneficiary between: the total exemption method andprogressive exemption method, on the one hand, and total crediting method and ordinary crediting m...

Double K-vacancy production by x-ray photoionization

International Nuclear Information System (INIS)

Southworth, S. H.; Dunford, R. W.; Kanter, E. P.; Krassig, B.; Young, L.; Armen, G. B.; Levin, J. C.; Chen, M. H.; Ederer, D. L.

2002-01-01

We have studied double K-shell photoionization of Ne and Mo (Z = 10 and 42) at the Advanced Photon Source. Double K-vacancy production in Ne was observed by recording the KK-KLL Auger hypersatellite spectrum. Comparison is made with calculations using the multiconfiguration Dirac-Fock method. For Mo, double K-vacancy production was observed by recording the Kα, β fluorescence hypersatellite and satellite x rays in coincidence. From the intensities of the Auger or x-ray hypersatellites relative to diagram lines, the probabilities for double K-vacancy production relative to single K-vacancies were determined. These results, along with reported measurements on other atoms, are compared with Z-scaling calculations of the high-energy limits of the double-to-single K-shell photoionization ratio

Double Photoionization Near Threshold

Science.gov (United States)

Wehlitz, Ralf

2007-01-01

The threshold region of the double-photoionization cross section is of particular interest because both ejected electrons move slowly in the Coulomb field of the residual ion. Near threshold both electrons have time to interact with each other and with the residual ion. Also, different theoretical models compete to describe the double-photoionization cross section in the threshold region. We have investigated that cross section for lithium and beryllium and have analyzed our data with respect to the latest results in the Coulomb-dipole theory. We find that our data support the idea of a Coulomb-dipole interaction.

Frequency Doubling Broadband Light in Multiple Crystals

International Nuclear Information System (INIS)

Alford, William J.; Smith, Arlee V.

2000-01-01

The authors compare frequency doubling of broadband light in a single nonlinear crystal with doubling in five crystals with intercrystal temporal walk off compensation, and with doubling in five crystals adjusted for offset phase matching frequencies. Using a plane-wave, dispersive numerical model of frequency doubling they study the bandwidth of the second harmonic and the conversion efficiency as functions of crystal length and fundamental irradiance. For low irradiance the offset phase matching arrangement has lower efficiency than a single crystal of the same total length but gives a broader second harmonic bandwidth. The walk off compensated arrangement gives both higher conversion efficiency and broader bandwidth than a single crystal. At high irradiance, both multicrystal arrangements improve on the single crystal efficiency while maintaining broad bandwidth

Transition from single to multiple double layers

International Nuclear Information System (INIS)

Chan, C.; Hershkowitz, N.

1982-01-01

It is shown that laboratory double layers become multiple double layers when the ratio of Debye length to system length is decreased. This result exhibits characteristics described by boundary layer theory

Air (CO2) double-contrast barium enteroclysis.

Science.gov (United States)

Maglinte, Dean D T; Kohli, Marc D; Romano, Stefania; Lappas, John C

2009-09-01

In the 1980s and 1990s in North America and Europe, air (CO(2)) double-contrast barium enteroclysis took a back seat to biphasic methylcellulose double-contrast enteroclysis in the investigation of small-bowel diseases. The widespread application of capsule endoscopy in the 21st century has identified a number of limitations of radiologic examinations in the investigation of mucosal diseases of the small intestine. Evidence-based studies comparing barium, computed tomographic (CT), and magnetic resonance (MR) enteroclysis have shown that in spite of improvements in small-bowel examination methods using CT and MR, barium examinations remain superior in the depiction of mucosal abnormalities, particularly the apthoid lesions of early Crohn disease. Barium small-bowel examinations have been recommended in the patient with a negative CT or MR enteroclysis study where the pretest probability of Crohn disease is high. A recent prospective comparison of methylcellulose double-contrast barium enteroclysis to capsule endoscopy with review of the literature has shown that air enteroclysis depicts mucosal details better than does methylcellulose double-contrast enteroclysis because of the "washout" effect of methylcellulose on superficial mucosal features. Recent articles have shown that air enteroclysis compares favorably with wireless capsule endoscopy and double-balloon endoscopy in the diagnosis of mucosal abnormalities of the small bowel. This article describes the authors' technique of performing air double-contrast enteroclysis, its clinical indications, and its pitfalls.

Speeded Recognition of Ungrammaticality: Double Violations.

Science.gov (United States)

Moore, Timothy E.; Biederman, Irving

1979-01-01

The speed at which sentences with various kinds of violations could be rejected was studied. Compatible with the sequential model was the finding that noun-verb and adjective-noun double violations did not result in shorter reaction times than noun-verb single violations, although double violations were judged less acceptable. (Author/RD)

Double charge exchange and generalized seniority

International Nuclear Information System (INIS)

Ginocchio, J.N.

1993-01-01

The double charge exchange transition matrix elements from an even-even target to the double isobaric analog state and the ground state are derived in the generalized seniority model as a function of the number of valence nucleons. Crucial differences with the seniority model are found and their consequences are discussed. (orig.)

The Double R Theory of Language Comprehension

National Research Council Canada - National Science Library

Ball, Jerry

2004-01-01

... (also known as Cognitive Semantics). This technical report explicates the basic principles and assumptions of Double R Grammar and compares Double R Grammar to Chomsky's X-Bar Theory as well as Langacker's Cognitive Linguistic...

Is double-gloving really protective? A comparison between the glove perforation rate among perioperative nurses with single and double gloves during surgery.

Science.gov (United States)

Guo, Yue Ping; Wong, Po Ming; Li, Yi; Or, Peggy Pui Lai

2012-08-01

Surgical teams rely on surgical gloves as a barrier to protect themselves against blood-borne pathogenic infections during surgery. Double-gloving is adopted by surgeons to tackle the problem of glove perforation. Nevertheless, double-gloving is not practiced commonly by operating room nurses and there are only limited studies about double-gloving that targets only perioperative nurses. The aim of this research was to assess the effectiveness of double-gloving in protecting perioperative nurses by comparing the frequency of glove perforation between single-gloving and double-gloving groups. A prospective and randomized study was performed. Nurses were assigned randomly to single-gloved and double-gloved groups for comparison of the glove perforation rate. Water-leakage and air-inflation tests were used to detect glove perforation. Glove perforations was detected in 10 of 112 sets of single-gloves (8.9%) and 12 of 106 sets of outer gloves in the double-gloved group (11.3%). There was no inner double-glove perforation (0%). Glove perforations were found in 6 and 4 of the 112 sets of single-gloves for the first assistants (5.36%) and the scrub nurses (3.57%), and 5 and 7 of 106 sets of outer gloves in the double-gloved group for the first assistants (4.72%) and the scrub nurses (6.60%), respectively. The average occurrence of perforation was 69.8 minutes (range, 20-110 min) after the beginning of surgery. The sites of perforation were localized mostly on the left middle finger (42%) and the left ring finger (33.3%). Based on the findings of the study, double-gloving is indeed effective in protecting operating room nurses against blood-borne pathogen exposure. It should be introduced as a routine practice. Copyright © 2012 Elsevier Inc. All rights reserved.

Methods of Mitigating Double Taxation

OpenAIRE

Lindhe, Tobias

2002-01-01

This paper presents a comprehensive overview of existing methods of mitigating double taxation of corporate income within a standard cost of capital model. Two of the most well-known and most utilized methods, the imputation and the split rate systems, do not mitigate double taxation in corporations where the marginal investment is financed with retained earnings. However, all methods are effective when the marginal investment is financed with new share issues. The corporate tax rate, fiscal ...

Conductance in double quantum well systems

International Nuclear Information System (INIS)

Hasbun, J E

2003-01-01

The object of this paper is to review the electronic conductance in double quantum well systems. These are quantum well structures in which electrons are confined in the z direction by large band gap material barrier layers, yet form a free two-dimensional Fermi gas within the sandwiched low band gap material layers in the x-y plane. Aspects related to the conductance in addition to the research progress made since the inception of such systems are included. While the review focuses on the tunnelling conductance properties of double quantum well devices, the longitudinal conductance is also discussed. Double quantum well systems are a more recent generation of structures whose precursors are the well known double-barrier resonant tunnelling systems. Thus, they have electronic signatures such as negative differential resistance, in addition to resonant tunnelling, whose behaviours depend on the wavefunction coupling between the quantum wells. As such, the barrier which separates the quantum wells can be tailored in order to provide better control of the device's electronic properties over their single well ancestors. (topical review)

Double tracks test site characterization report

International Nuclear Information System (INIS)

1996-05-01

This report presents the results of site characterization activities performed at the Double Tracks Test Site, located on Range 71 North, of the Nellis Air Force Range (NAFR) in southern Nevada. Site characterization activities included reviewing historical data from the Double Tracks experiment, previous site investigation efforts, and recent site characterization data. The most recent site characterization activities were conducted in support of an interim corrective action to remediate the Double Tracks Test Site to an acceptable risk to human health and the environment. Site characterization was performed using a phased approach. First, previously collected data and historical records sere compiled and reviewed. Generalized scopes of work were then prepared to fill known data gaps. Field activities were conducted and the collected data were then reviewed to determine whether data gaps were filled and whether other areas needed to be investigated. Additional field efforts were then conducted, as required, to adequately characterize the site. Characterization of the Double Tracks Test Site was conducted in accordance with the US Department of Energy's (DOE) Streamlined Approach for Environmental Restoration (SAFER)

Nuclear structure and double beta decay

International Nuclear Information System (INIS)

Vogel, P.

1988-01-01

Double beta decay is a rare transition between two nuclei of the same mass number A involving a change of the nuclear charge Z by two units. It has long been recognized that the Oν mode of double beta decay, where two electrons and no neutrinos are emitted, is a powerful tool for the study of neutrino properties. Its observation would constitute a convincing proof that there exists a massive Majorana neutrino which couples to electrons. Double beta decay is a process involving an intricate mixture of particle physics and physics of the nucleus. The principal nuclear physics issues have to do with the evaluation of the nuclear matrix elements responsible for the decay. If the authors wish to arrive at quantitative answers for the neutrino properties the authors have no choice but to learn first how to understand the nuclear mechanisms. The authors describe first the calculation of the decay rate of the 2ν mode of double beta decay, in which two electrons and two antineutrinos are emitted

The Dissolution of Double Holliday Junctions

DEFF Research Database (Denmark)

Bizard, Anna H; Hickson, Ian D

2014-01-01

as "double Holliday junction dissolution." This reaction requires the cooperative action of a so-called "dissolvasome" comprising a Holliday junction branch migration enzyme (Sgs1/BLM RecQ helicase) and a type IA topoisomerase (Top3/TopoIIIα) in complex with its OB (oligonucleotide/oligosaccharide binding......Double Holliday junctions (dHJS) are important intermediates of homologous recombination. The separate junctions can each be cleaved by DNA structure-selective endonucleases known as Holliday junction resolvases. Alternatively, double Holliday junctions can be processed by a reaction known......) fold containing accessory factor (Rmi1). This review details our current knowledge of the dissolution process and the players involved in catalyzing this mechanistically complex means of completing homologous recombination reactions....

46 CFR 173.058 - Double bottom requirements.

Science.gov (United States)

2010-10-01

... PERTAINING TO VESSEL USE School Ships § 173.058 Double bottom requirements. Each new sailing school vessel... service must comply with the double bottom requirements in §§ 171.105 through 171.109, inclusive, of this...

International and national aspects of double taxation

OpenAIRE

Doležalová, Veronika

2007-01-01

Veronika Doležalová Mezinárodní a vnitrostátní aspekty dvojího zdan ní 160 International and national aspects of double taxation - Resumé This thesis pays attention to the area of double taxation and its related national as well as international aspects. The reason for discussing this subject was its importance for removing the obstacles that double taxation presents to the development of economic relations between countries. The thesis is divided into five chapters. There are six annexes att...

Gravitational double layers

International Nuclear Information System (INIS)

Senovilla, José M M

2014-01-01

I analyze the properties of thin shells through which the scalar curvature R is discontinuous in gravity theories with Lagrangian F(R) = R − 2Λ + αR 2 on the bulk. These shells/domain walls are of a new kind because they possess, in addition to the standard energy–momentum tensor, an external energy flux vector, an external scalar pressure/tension and, most exotic of all, another energy–momentum contribution resembling classical dipole distributions on a shell: a double layer. I prove that all these contributions are necessary to make the entire energy–momentum tensor divergence-free. This is the first known occurrence of such a type of double layer in a gravity theory. I present explicit examples in constant-curvature five-dimensional bulks, with a brief study of their properties: new physical behaviors arise. (fast track communications)

Experimental research of double-pulse linear induction electron accelerator

International Nuclear Information System (INIS)

Liao Shuqing; Cheng Cheng; Zheng Shuxin; Tang Chuanxiang; Lin Yuzheng; Jing Xiaobing; Mu Fan; Pan Haifeng

2009-01-01

The Mini-LIA is a double-pulse linear induction electron accelerator with megahertz repetition rates, which consists of a double-pulse power system, a thermal cathode electron gun, two induction cells, beam transportation systems and diagnosis systems, etc. Experiments of the Mini-LIA have been conducted. The double-pulse high voltage was obtained with several hundred nanosecond pulse intervals (i. e. megahertz repetition rate) and each pulse had an 80 kV amplitude with a FWHM of 80 ns. In the gap of the induction cell, the double-pulse accelerating electric field was measured via E-field probes, and the double-pulse electron beam with a current about 1.1 A has been obtained at the Mini-LIA exit. These experimental results show that the double-pulse high voltage with megahertz repetition rates can be generated by an insulation and junction system. And they also indicate that the induction cell with metglas as the ferromagnetic material and the LaB 6 thermal cathode electron gun suit the double-pulse operation with megahertz repetition rates. (authors)

Conformational changes in fragments D and double-D from human fibrin(ogen) upon binding the peptide ligand Gly-His-Arg-Pro-amide.

Science.gov (United States)

Everse, S J; Spraggon, G; Veerapandian, L; Doolittle, R F

1999-03-09

The structure of fragment double-D from human fibrin has been solved in the presence and absence of the peptide ligands that simulate the two knobs exposed by the removal of fibrinopeptides A and B, respectively. All told, six crystal structures have been determined, three of which are reported here for the first time: namely, fragments D and double-D with the peptide GHRPam alone and double-D in the absence of any peptide ligand. Comparison of the structures has revealed a series of conformational changes that are brought about by the various knob-hole interactions. Of greatest interest is a moveable "flap" of two negatively charged amino acids (Glubeta397 and Aspbeta398) whose side chains are pinned back to the coiled coil with a calcium atom bridge until GHRPam occupies the beta-chain pocket. Additionally, in the absence of the peptide ligand GPRPam, GHRPam binds to the gamma-chain pocket, a new calcium-binding site being formed concomitantly.

A double patella-like condition secondary to synovial osteochondromatosis

Directory of Open Access Journals (Sweden)

Kajikawa Yoshiteru

2012-09-01

Full Text Available Abstract To our knowledge, this is the first case of synovial osteochondromatosis in a patient presenting with a double patella-like condition. The true duplication of the patella, which is called double patella, is extremely rare. In our case, the operative and histopathological findings showed that the double patella-like condition was secondarily induced by synovial osteochondromatosis. Synovial osteochondromatosis should be considered as a differential diagnosis for congenital double patella.

Functional and structural outcomes of single-row versus double-row versus combined double-row and suture-bridge repair for rotator cuff tears.

Science.gov (United States)

Mihata, Teruhisa; Watanabe, Chisato; Fukunishi, Kunimoto; Ohue, Mutsumi; Tsujimura, Tomoyuki; Fujiwara, Kenta; Kinoshita, Mitsuo

2011-10-01

Although previous biomechanical research has demonstrated the superiority of the suture-bridge rotator cuff repair over double-row repair from a mechanical point of view, no articles have described the structural and functional outcomes of this type of procedure. The structural and functional outcomes after arthroscopic rotator cuff repair may be different between the single-row, double-row, and combined double-row and suture-bridge (compression double-row) techniques. Cohort study; Level of evidence, 3. There were 206 shoulders in 201 patients with full-thickness rotator cuff tears that underwent arthroscopic rotator cuff repair. Eleven patients were lost to follow-up. Sixty-five shoulders were repaired using the single-row, 23 shoulders using the double-row, and 107 shoulders using the compression double-row techniques. Clinical outcomes were evaluated at an average of 38.5 months (range, 24-74 months) after rotator cuff repair. Postoperative cuff integrity was determined using Sugaya's classification of magnetic resonance imaging (MRI). The retear rates after arthroscopic rotator cuff repair were 10.8%, 26.1%, and 4.7%, respectively, for the single-row, double-row, and compression double-row techniques. In the subcategory of large and massive rotator cuff tears, the retear rate in the compression double-row group (3 of 40 shoulders, 7.5%) was significantly less than those in the single-row group (5 of 8 shoulders, 62.5%, P row group (5 of 12 shoulders, 41.7%, P row and suture-bridge techniques, which had the lowest rate of postoperative retear, is an effective option for arthroscopic repair of the rotator cuff tendons because the postoperative functional outcome in patients with a retear is inferior to that without retear.

The double copy: Bremsstrahlung and accelerating black holes

CERN Document Server

Luna, Andres; Nicholson, Isobel; O'Connell, Donal; White, Chris D

2016-01-01

Advances in our understanding of perturbation theory suggest the existence of a correspondence between classical general relativity and Yang-Mills theory. A concrete example of this correspondence, which is known as the double copy, was recently introduced for the case of stationary Kerr-Schild spacetimes. Building on this foundation, we examine the simple time-dependent case of an accelerating, radiating point source. The gravitational solution, which generalises the Schwarzschild solution, includes a non-trivial stress-energy tensor. This stress-energy tensor corresponds to a gauge theoretic current in the double copy. We interpret both of these sources as representing the radiative part of the field. Furthermore, in the simple example of Bremsstrahlung, we determine a scattering amplitude describing the radiation, maintaining the double copy throughout. Our results provide the strongest evidence yet that the classical double copy is directly related to the BCJ double copy for scattering amplitudes.

The International Double Taxation – Avoiding Methods

Directory of Open Access Journals (Sweden)

Nicoleta Barbuta-Misu

2009-06-01

Full Text Available The paper presents the main causes that determine double taxation, its forms, i.e. the economicdouble taxation and the international legal double taxation, the need for eliminating the double taxation andavoiding methods. In the presentation of the avoidance methods have been used practical examples forcomparison of the tax advantages for income beneficiary between: the total exemption method andprogressive exemption method, on the one hand, and total crediting method and ordinary crediting method,on the other hand, but the comparing of tax reduction between methods of exemption and crediting.

A rare anomaly: Double right coronary artery

Directory of Open Access Journals (Sweden)

Dursun Çayan Akkoyun

2013-01-01

Full Text Available Coronary artery anomalies are rare anomalies. Theseare usually asymptomatic and are discovered incidentally.Double right coronary artery (RCA is a rare coronaryartery anomaly. Although there is controversy aboutidentification and classification of double RCA, it is oftena benign condition, but it can be complicated by atherosclerosisand can lead to serious conditions such asmyocardial infarction (MI and may be accompanied byother anomalies. In our case, double RCA were detectedin coronary angiography for acute anterior MI, and in thenext session successful percutaneous coronary interventionwas performed.Key words: Coronary anomaly, coronary angiography,coronary stenosis

Review of modern double beta decay experiments

Science.gov (United States)

Barabash, A. S.

2015-10-01

The review of modern experiments on search and studying of double beta decay processes is done. Results of the most sensitive current experiments are discussed. The main attention is paid to EXO-200, KamLAND-Zen, GERDA-I and CUORE-0 experiments. Modern values of T1/2(2ν) and best present limits on neutrinoless double beta decay and double beta decay with Majoron emission are presented. Conservative limits on effective mass of a Majorana neutrino ( at the level of ˜ 0.01-0.1 eV are discussed.

Stationary Double Layers in a Collisionless Magnetoplasma

DEFF Research Database (Denmark)

Noriyoshi, Sato; Mieno, Tetsu; Hatakeyama, Rikizo

1983-01-01

of the plate on the low-potential side, being accompanied with current limitation. This localized potential drop moves along the plasma column, but finally stops and results in the formation of the stationary double layer in the presence of sufficient plasma supply from the plate on the high-potential side.......Stationary double layers are generated in a magnetoplasma by applying potential differences between two heated plates on which the plasma is produced by surface ionization. By measuring the double-layer formation process, a localized potential drop is found to be formed initially in front...

Double photoionisation spectra of molecules

CERN Document Server

Eland, John

2017-01-01

This book contains spectra of the doubly charged positive ions (dications) of some 75 molecules, including the major constituents of terrestrial and planetary atmospheres and prototypes of major chemical groups. It is intended to be a new resource for research in all areas of molecular spectroscopy involving high energy environments, both terrestrial and extra-terrestrial. All the spectra have been produced by photoionisation using laboratory lamps or synchrotron radiation and have been measured using the magnetic bottle time-of-flight technique by coincidence detection of correlated electron pairs. Full references to published work on the same species are given, though for several molecules these are the first published spectra. Double ionisation energies are listed and discussed in relation to the molecular electronic structure of the molecules. A full introduction to the field of molecular double ionisation is included and the mechanisms by which double photoionisation can occur are examined in detail. A p...

Total Maxillary Reconstruction Using a Double-Barreled and Double Skin Paddle Fibular Flap after Total Maxillectomy

Directory of Open Access Journals (Sweden)

Miguel de la Parra

2013-11-01

Full Text Available Chondroblastomas are rare entities accounting for approximately 1% of all primary bone tumors. We describe a case of a 7-year-old girl with a giant chondroblastoma of the maxilla, treated with bilateral class III maxillectomy and reconstruction with a double-barreled and double skin paddle fibular free flap. We show evidence of an excellent aesthetic outcome at 6 months' follow up with no evidence of tumor recurrence.

Total Maxillary Reconstruction Using a Double-Barreled and Double Skin Paddle Fibular Flap after Total Maxillectomy

Science.gov (United States)

Sanchez, Gerardo; Lopez, Jaime; Perez, Adrian; Naal, Norberto

2013-01-01

Chondroblastomas are rare entities accounting for approximately 1% of all primary bone tumors. We describe a case of a 7-year-old girl with a giant chondroblastoma of the maxilla, treated with bilateral class III maxillectomy and reconstruction with a double-barreled and double skin paddle fibular free flap. We show evidence of an excellent aesthetic outcome at 6 months' follow up with no evidence of tumor recurrence. PMID:24286054

CAD/CAM for Double Woven Fabric

Directory of Open Access Journals (Sweden)

Moussa Alali

2014-02-01

Full Text Available To bond the two layers in double fabrics, various types of stitching can be distinguished such as self-stitching, double stitching, center warp stitching, center weft stitching, and so on. In this article, a mathematic model based on a software program has been developed to automatically generate a double fabric stitched by additional warp called center warp. Each layer has been represented in a 2D binary matrix, and a new matrix called warps order matrix has been defined to demonstrate the modality of position of the center warps in relating to the top and bottom fabrics’ warps. After insertion of all warps in the extended weave matrix, the lifter conditions has been discussed and the stitching points have been determined.

Double aortic arch

Science.gov (United States)

Surgery can be done to fix double aortic arch. The surgeon ties off the smaller branch and separates it from the larger branch. Then the surgeon closes the ends of the aorta with stitches. This relieves pressure on the esophagus and windpipe.

Double-Stranded Peptide Nucleic Acids

DEFF Research Database (Denmark)

2001-01-01

A novel class of compounds, known as peptide nucleic acids, form double-stranded structures with one another and with ssDNA. The peptide nucleic acids generally comprise ligands such as naturally occurring DNA bases attached to a peptide backbone through a suitable linker.......A novel class of compounds, known as peptide nucleic acids, form double-stranded structures with one another and with ssDNA. The peptide nucleic acids generally comprise ligands such as naturally occurring DNA bases attached to a peptide backbone through a suitable linker....

F observable in double π{sup 0}-photoproduction

Energy Technology Data Exchange (ETDEWEB)

Garni, Stefanie [Department of Physics, University of Basel, CH-4056 Basel (Switzerland); Collaboration: A2-Collaboration

2014-07-01

The measurement of single and double polarization observables gives information about the different resonance contributions in the cross section and hence leads to a better understanding of the nucleon and its excited states. The double π{sup 0}-photoproduction is one of the most interesting reaction for the measurement of these observables. It allows to search for excited nucleon states which decay preferentially via cascades involving intermediate excited states. Furthermore, the background from non-resonant terms is small since the photon does not couple directly to neutral pions. Double π{sup 0}-photoproduction off a transversally polarized H-Butanol target has been measured using circularly polarized bremsstrahlung photons produced by MAMI-C with incident energies up to 1.5 GeV. The double π{sup 0} reaction was identified using a combined setup of the Crystal Ball colorimeter and a TAPS forward wall which results in an almost 4π acceptance. Preliminary results on the single polarization observable T and double polarization observable F are presented.

Preparation of uranium ingots from double fluorides

International Nuclear Information System (INIS)

Le Boulbin, E.

1967-05-01

A simple method has been developed for the preparation of uranium double fluorides and has given a new impetus to the study of the reduction of these compounds with a view to obtaining very pure uranium ingots. This reduction can be carried out using calcium or magnesium as the reducing agent, this latter metal being very interesting from the practical point of view. A comparative study of the heat balances of the reduction processes for the double fluorides and for uranium tetrafluoride has shown that reduction of the double fluorides is possible. The exact experimental conditions for these reductions have been determined. Our study has shown in particular that the reduction of the double salt UF 4 , CaF 2 by magnesium leads to the production of small (20 to 500 g) samples of high-purity uranium with a yield of 99 per cent. (author) [fr

Review of modern double beta decay experiments

Energy Technology Data Exchange (ETDEWEB)

Barabash, A. S., E-mail: barabash@itep.ru [Institute of Theoretical and Experimental Physics (NRC ”Kurchatov Institute”), B. Cheremushkinskaya 25, Moscow (Russian Federation)

2015-10-28

The review of modern experiments on search and studying of double beta decay processes is done. Results of the most sensitive current experiments are discussed. The main attention is paid to EXO-200, KamLAND-Zen, GERDA-I and CUORE-0 experiments. Modern values of T{sub 1/2}(2ν) and best present limits on neutrinoless double beta decay and double beta decay with Majoron emission are presented. Conservative limits on effective mass of a Majorana neutrino (〈m{sub ν}〉 < 0.46 eV) and a coupling constant of Majoron to neutrino (〈g{sub ee}〉 < 1.3 · 10{sup −5}) are obtained. Prospects of search for neutrinoless double beta decay in new experiments with sensitivity to 〈m{sub ν}〉 at the level of ∼ 0.01-0.1 eV are discussed.

Subatmospheric double containment system

International Nuclear Information System (INIS)

Gans, D. Jr.; Noble, J.H.

1978-01-01

A reinforced concrete double wall nuclear containment structure with each wall including an essentially impervious membrane or liner and porous concrete filling the annulus between the two walls is described. The interior of the structure is maintained at subatmospheric pressure, and the annulus between the two walls is maintained at a subatmospheric pressure intermediate between that of the interior and the surrounding atmospheric pressure, during normal operation. In the event of an accident within the containment structure the interior pressure may exceed atmospheric pressure, but leakage from the interior to the annulus between the double walls will not result in the pressure of the annulus exceeding atmospheric pressure so that there is no net outleakage from the containment structure

Double rupture disc experience

International Nuclear Information System (INIS)

1979-01-01

Result of these observations, comparisons and evaluations can be summarized in the following list of concerns regarding the use of double rupture discs coupled to the liquid space of a steam generator that is subjected to a large leak sodium water reaction event. Single rupture disc show delayed collapse characteristics in LLTR Series I and double disc assemblies are presumed to be more complex with additional delay before opening to give pressure relief. Delayed failure increases pressures in the IHTS and must be adequately covered by design requirements. With CRBR design, the first disc may fail only partially reducing the loading on the second disc with the result that relief performance may not meet requirements

Ultrastrong Stationary Double Layers in a Nondischarge Magnetoplasma

DEFF Research Database (Denmark)

Sato, N.; Hatakeyama, R.; Iizuka, S.

1981-01-01

Ultrastrong stationary double layers are generated in a magnetoplasma by simply applying potential differences between two plasma sources. The potential drop ϕD of the double layer is increased up to eϕD/Te≃2×103 (Te is the electron temperature in eV) with no difficulties caused by gas discharge....... There are always large spiky fluctuations on the low-potential tail of the double layers....

Double parton scattering. A tale of two partons

Energy Technology Data Exchange (ETDEWEB)

Kasemets, Tomas

2013-08-15

Double parton scattering in proton-proton collisions can give sizable contributions to final states in parts of phase space. We investigate the correlations between the partons participating in the two hard interactions of double parton scattering. With a detailed calculation of the differential cross section for the double Drell-Yan process we demonstrate how initial state correlations between the partons affect the rate and distribution of final state particles. We present our results with focus on correlations between the polarizations of the partons. In particular transversely polarized quarks lead to a dependence of the cross section on angles between final state particles of the two hard interactions, and thereby on the invariant mass of particle pairs. The size of the spin correlations, and therewith the degree to which the final state particles are correlated, depends on unknown double parton distributions. We derive positivity bounds on the double parton distributions that follow from their interpretation as probability densities, taking into account all possible spin correlations between two partons in an unpolarized proton. We show that the bounds are stable under homogeneous leading-order DGLAP evolution to higher scales. We make direct use of the positivity bounds in numerical investigations on the double DGLAP evolution for two linearly polarized gluons and for two transversely polarized quarks. We find that the linearly polarized gluons are likely to be negligible at high scales but that transversely polarized quarks can still play a significant role. We examine the dependence of the double parton distributions on the transverse distance between the two partons, and therewith between the two hard interactions. We further study the interplay between transverse and longitudinal variables of the distributions, as well as the impact of the differences in integration limits between the evolution equations for single and double parton distributions. (orig.)

Double nanosecond pulses generation in ytterbium fiber laser

Energy Technology Data Exchange (ETDEWEB)

Veiko, V. P.; Samokhvalov, A. A., E-mail: samokhvalov.itmo@gmail.com; Yakovlev, E. B.; Zhitenev, I. Yu.; Kliushin, A. N. [Saint-Petersburg State University of Information Technologies, Mechanics and Optics, Kronverksky Pr. 49, Saint Petersburg (Russian Federation); Lednev, V. N. [Prokhorov General Physics Institute of the Russian Academy of Sciences, Vavilov Str., 38, Moscow (Russian Federation); National University of Science and Technology MISiS, Leninskyave., 4, Moscow (Russian Federation); Pershin, S. M. [Prokhorov General Physics Institute of the Russian Academy of Sciences, Vavilov Str., 38, Moscow (Russian Federation)

2016-06-15

Double pulse generation mode for nanosecond ytterbium fiber laser was developed. Two sequential 60-200 ns laser pulses with variable delay between them were generated by acousto-optic modulator opening with continuous diode pumping. A custom radio frequency generator was developed to produce two sequential “opening” radio pulses with a delay of 0.2–1 μs. It was demonstrated that double pulse generation did not decrease the average laser power while providing the control over the laser pulse power profile. Surprisingly, a greater peak power in the double pulse mode was observed for the second laser pulse. Laser crater studies and plasma emission measurements revealed an improved efficiency of laser ablation in the double pulse mode.

Lifespan extension and the doctrine of double effect.

Science.gov (United States)

Capitaine, Laura; Devolder, Katrien; Pennings, Guido

2013-06-01

Recent developments in biogerontology--the study of the biology of ageing--suggest that it may eventually be possible to intervene in the human ageing process. This, in turn, offers the prospect of significantly postponing the onset of age-related diseases. The biogerontological project, however, has met with strong resistance, especially by deontologists. They consider the act of intervening in the ageing process impermissible on the grounds that it would (most probably) bring about an extended maximum lifespan--a state of affairs that they deem intrinsically bad. In a bid to convince their deontological opponents of the permissibility of this act, proponents of biogerontology invoke an argument which is grounded in the doctrine of double effect. Surprisingly, their argument, which we refer to as the 'double effect argument', has gone unnoticed. This article exposes and critically evaluates this 'double effect argument'. To this end, we first review a series of excerpts from the ethical debate on biogerontology in order to substantiate the presence of double effect reasoning. Next, we attempt to determine the role that the 'double effect argument' is meant to fulfil within this debate. Finally, we assess whether the act of intervening in ageing actually can be justified using double effect reasoning.

Double soft theorem for perturbative gravity

OpenAIRE

Saha, Arnab

2016-01-01

Following up on the recent work of Cachazo, He and Yuan \\cite{arXiv:1503.04816 [hep-th]}, we derive the double soft graviton theorem in perturbative gravity. We show that the double soft theorem derived using CHY formula precisely matches with the perturbative computation involving Feynman diagrams. In particular, we find how certain delicate limits of Feynman diagrams play an important role in obtaining this equivalence.

ITER PF6 double pancakes winding line

Energy Technology Data Exchange (ETDEWEB)

Du, Shuangsong [Institute of Plasma Physics, Chinese Academy of Science, Hefei (China); University of Science and Technology of China, Hefei (China); Wen, Wei, E-mail: wenwei@ipp.ac.cn [Institute of Plasma Physics, Chinese Academy of Science, Hefei (China); Chen, Jin; Wu, Weiyue; Song, Yuntao; Shen, Guang [Institute of Plasma Physics, Chinese Academy of Science, Hefei (China)

2017-03-15

Highlights: • ITER PF6 double pancakes “two-in-hand” winding line layout and main parameters were introduced, main winding sequences were also included. • Main features of each winding unit include de-spooling unit, straightening unit, sandblasting and cleaning unit, bending unit, turn insulation wrapping head, rotary table and automatic control system were depicted. • PF6 double pancake winding line was commissioned with PF5 empty jacket conductor after the installation and testing of each unit, ±0.5 mm turn positioning and ±2 turn to turn deviations were achieved. - Abstract: The Poloidal Field (PF) coils are one of the main sub-systems of the ITER magnets. The PF6 coil is being manufactured by the Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP) as per the Poloidal Field coils cooperation agreement signed between ASIPP and Fusion for Energy (F4E).The ITER PF6 winding pack is composed by stacking of 9 double pancakes. Each double pancake is wound with a “two-in-hand” configuration. This paper describes the ITER PF6 double pancakes winding line, including layout and main parameters of the winding line, features of main units and the commissioning trial with PF5 empty jacket conductor.

Advanced double-biprism holography with atomic resolution

Energy Technology Data Exchange (ETDEWEB)

Genz, Florian, E-mail: florian.genz@physik.tu-berlin.de [Technische Universität Berlin, Institut für Optik und Atomare Physik, Straße des 17. Juni, 10623 Berlin (Germany); Niermann, Tore [Technische Universität Berlin, Institut für Optik und Atomare Physik, Straße des 17. Juni, 10623 Berlin (Germany); Buijsse, Bart; Freitag, Bert [FEI Company, Achtseweg Noord 5, 5651 GG Eindhoven (Netherlands); Lehmann, Michael [Technische Universität Berlin, Institut für Optik und Atomare Physik, Straße des 17. Juni, 10623 Berlin (Germany)

2014-12-15

The optimum biprism position as suggested by Lichte (Ultramicroscopy 64 (1996) 79 [10]) was implemented into a state-of-the-art transmission electron microscope. For a setup optimized for atomic resolution holograms with a width of 30 nm and a fringe spacing of 30 pm, we investigated the practical improvements on hologram quality. The setup is additionally supplemented by a second biprism as suggested by Harada et al. (Applied Physics Letters 84 (2004) 3229 [12]). In order to estimate the possibilities and limitations of the double biprism setup, geometric optics arguments lead to calculation of the exploitable shadow width, necessary for strong reduction of biprism-induced artefacts. Additionally, we used the double biprism setup to estimate the biprism vibration, yielding the most stable imaging conditions with lowest overall fringe contrast damping. Electron holograms of GaN demonstrate the good match between experiment and simulation, also as a consequence of the improved stability. - Highlights: • Investigation of optimum biprism position implementation into state-of-the-art TEM. • Reduction of artefacts, especially vignetting in double-biprism electron holography. • Biprism vibration and most stable imaging conditions in double-biprism holography. • Demonstration of the optimized double-biprism setup using a thin GaN-foil.

Lightweight Double Neutron Star Found

Science.gov (United States)

Kohler, Susanna

2018-02-01

More than forty years after the first discovery of a double neutron star, we still havent found many others but a new survey is working to change that.The Hunt for PairsThe observed shift in the Hulse-Taylor binarys orbital period over time as it loses energy to gravitational-wave emission. [Weisberg Taylor, 2004]In 1974, Russell Hulse and Joseph Taylor discovered the first double neutron star: two compact objects locked in a close orbit about each other. Hulse and Taylors measurements of this binarys decaying orbit over subsequent years led to a Nobel prize and the first clear evidence of gravitational waves carrying energy and angular momentum away from massive binaries.Forty years later, we have since confirmed the existence of gravitational waves directly with the Laser Interferometer Gravitational-Wave Observatory (LIGO). Nonetheless, finding and studying pre-merger neutron-star binaries remains a top priority. Observing such systems before they merge reveals crucial information about late-stage stellar evolution, binary interactions, and the types of gravitational-wave signals we expect to find with current and future observatories.Since the Hulse-Taylor binary, weve found a total of 16 additional double neutron-star systems which represents only a tiny fraction of the more than 2,600 pulsars currently known. Recently, however, a large number of pulsar surveys are turning their eyes toward the sky, with a focus on finding more double neutron stars and at least one of them has had success.The pulse profile for PSR J1411+2551 at 327 MHz. [Martinez et al. 2017]A Low-Mass DoubleConducted with the 1,000-foot Arecibo radio telescope in Puerto Rico, the Arecibo 327 MHz Drift Pulsar Survey has enabled the recent discovery of dozens of pulsars and transients. Among them, as reported by Jose Martinez (Max Planck Institute for Radio Astronomy) and coauthors in a recent publication, is PSR J1411+2551: a new double neutron star with one of the lowest masses ever measured

Application of international double taxation conventions in Romania

OpenAIRE

Florin Dumiter; Ștefania Jimon

2016-01-01

In this article we sought to address the international double taxation phenomenon from two different standpoints. To begin with, in the first part we analysed the framework of international double taxation, and how this topic was tackled in both Romanian and international literature.International double taxation has been analyzed, mutatis mutandis, from an economic perspective, more precisely in terms of the implications that it generates on economies, on added value, on capital flows, on the...

The history of double tax conventions in Croatia

OpenAIRE

Hrvoje Arbutina; Nataša Žunić Kovačević

2014-01-01

After a short introduction, the authors briefly describe the national experience in handling the problems of international double taxation through double tax conventions. This chapter is divided according to stages in the history of double tax conventions identified. The authors analyse the goals of tax treaty policies in differentiated stages with a survey of the economic implications. Special focus is placed on inter-country influences and the impact on and of international institutions and...

Monitoring of Double-Stud Wall Moisture Conditions in the Northeast

Energy Technology Data Exchange (ETDEWEB)

Ueno, K. [Building Science Corporation, Westford, MA (United States)

2015-03-01

Double-stud walls insulated with cellulose or low-density spray foam can have R-values of 40 or higher. However, double-stud walls have a higher risk of interior-sourced condensation moisture damage when compared with high-R approaches using exterior insulating sheathing. Moisture conditions in double-stud walls were monitored in Zone 5A (Massachusetts); three double-stud assemblies were compared.

Monitoring of Double Stud Wall Moisture Conditions in the Northeast

Energy Technology Data Exchange (ETDEWEB)

Ueno, K. [Building Science Corporation, Westford, MA (United States)

2015-03-01

Double-stud walls insulated with cellulose or low-density spray foam can have R-values of 40 or higher. However, double stud walls have a higher risk of interior-sourced condensation moisture damage, when compared with high-R approaches using exterior insulating sheathing.; Moisture conditions in double stud walls were monitored in Zone 5A (Massachusetts); three double stud assemblies were compared.

Facilities for studying the double beta decay processes

International Nuclear Information System (INIS)

Zdesenko, Yu.G.

1980-01-01

Modern state, tendencies and perspectiVes of the development of experimental installations to study double β-decay are treated. The main peculiarities of direct recognition and full experiments on the study of double β-decay are considered. A simple ratio is obtained from statistical considerations which connects the life time limits of the nuclei with the facility parameters to conduct direct recognition experiments. Possibilities of different detectors are evaluated on the basis of the ratio. Requirements for the modern technique for complete investigation of double β-decay are formulated and two designs of facilities meeting the requirements are considered. It is shown that the facility with proportional chambers is more perspective. On the basis of the analysis of the facility development to study double β-decay, conclusion is made that the final and unambiguous proof of the existence of double β-decay process can be obtained only directly in the experiments with immediate recording of the decay acts. Possibilities of the existing and developed facilities to conduct recognition (direct) experiments are such, that with their help life time limits as to neutronless double β-decay at the level of 10 21 -10 22 years can be established. Counters on the basis of the condensed noble gases, semiconductor detectors made of TeCd, scintillators of big volume are the most perspective detectors. To conduct complete experiments it is necessary to develop a facility with sensitivity sufficient for the detection of two-neutrino double β-activeness when Tsub(1/2)=10sup(21) years [ru

Double counting in LDA + DMFT-The example of NiO

Energy Technology Data Exchange (ETDEWEB)

Karolak, M., E-mail: mkarolak@physnet.uni-hamburg.d [I. Institut fuer Theoretische Physik, Universitaet Hamburg, Jungiusstrasse 9, D-20355 Hamburg (Germany); Ulm, G.; Wehling, T. [I. Institut fuer Theoretische Physik, Universitaet Hamburg, Jungiusstrasse 9, D-20355 Hamburg (Germany); Mazurenko, V. [Theoretical Physics and Applied Mathematic Department, Urals State Technical University, 620002, Mira street 19, Yekaterinburg (Russian Federation); Poteryaev, A. [Institute of Metal Physics, Russian Academy of Sciences, 620041 Yekaterinburg GSP-170 (Russian Federation); Lichtenstein, A. [I. Institut fuer Theoretische Physik, Universitaet Hamburg, Jungiusstrasse 9, D-20355 Hamburg (Germany)

2010-07-15

An intrinsic issue of the LDA + DMFT approach is the so called double counting of interaction terms. How to choose the double-counting potential in a manner that is both physically sound and consistent is unknown. We have conducted an extensive study of the charge-transfer system NiO in the LDA + DMFT framework using quantum Monte Carlo and exact diagonalization as impurity solvers. By explicitly treating the double-counting correction as an adjustable parameter we systematically investigated the effects of different choices for the double counting on the spectral function. Different methods for fixing the double counting can drive the result from Mott insulating to almost metallic. We propose a reasonable scheme for the determination of double-counting corrections for insulating systems.

Limiting effects in double EEX beamline

Science.gov (United States)

Ha, G.; Power, J. G.; Conde, M.; Doran, D. S.; Gai, W.

2017-07-01

The double emittance exchange (EEX) beamline is suggested to overcome the large horizontal emittance and transverse jitter issues associated with the single EEX beamline while preserving its powerful phase-space manipulation capability. However, the double EEX beamline also has potential limitations due to coherent synchrotron radiation (CSR) and transverse jitter. The former limitation arises because double EEX uses twice as many bending magnets as single EEX which means stronger CSR effects degrading the beam quality. The latter limitation arises because a longitudinal jitter in front of the first EEX beamline is converted into a transverse jitter in the middle section (between the EEX beamlines) which can cause beam loss or beam degradation. In this paper, we numerically explore the effects of these two limitations on the emittance and beam transport.

Limiting effects in double EEX beamline

International Nuclear Information System (INIS)

Ha, G; Power, J G; Conde, M; Doran, D S; Gai, W

2017-01-01

The double emittance exchange (EEX) beamline is suggested to overcome the large horizontal emittance and transverse jitter issues associated with the single EEX beamline while preserving its powerful phase-space manipulation capability. However, the double EEX beamline also has potential limitations due to coherent synchrotron radiation (CSR) and transverse jitter. The former limitation arises because double EEX uses twice as many bending magnets as single EEX which means stronger CSR effects degrading the beam quality. The latter limitation arises because a longitudinal jitter in front of the first EEX beamline is converted into a transverse jitter in the middle section (between the EEX beamlines) which can cause beam loss or beam degradation. In this paper, we numerically explore the effects of these two limitations on the emittance and beam transport. (paper)

Pion double charge exchange and nuclear structure

International Nuclear Information System (INIS)

Ginocchio, J.N.

1987-01-01

Pion double charge exchange to both the double-analog state and the ground state is studied for medium weight nuclei. The relative cross section of these two transitions and the importance of nuclear structure as a function of pion kinetic energy is examined. 16 figs., 5 tabs

Formation of double-{Lambda} hypernuclei at PANDA

Energy Technology Data Exchange (ETDEWEB)

Gaitanos, T., E-mail: Theodoros.Gaitanos@theo.physik.uni-giessen.de [Institut fuer Theoretische Physik, Universitaet Giessen, D-35392, Giessen (Germany); Larionov, A.B.; Lenske, H.; Mosel, U. [Institut fuer Theoretische Physik, Universitaet Giessen, D-35392, Giessen (Germany)

2012-05-01

We study the formation of single- and double-{Lambda} hypernuclei in antiproton-induced reactions relevant for the forthcoming PANDA experiment at FAIR. We use the Giessen Boltzmann-Uehling-Uhlenbeck (GiBUU) transport model with relativistic mean-fields for the description of non-equilibrium dynamics and the statistical multifragmentation model (SMM) for fragment formation. This combined approach describes the dynamical properties of strangeness and fragments in low energy p{sup Macron}-induced reactions fairly well. We then focus on the formation of double-{Lambda} hypernuclei in high energy p{sup Macron}-nucleus collisions on a primary target including the complementary {Xi}-induced reactions to a secondary one, as proposed by the PANDA Collaboration. Our results show that a copious production of double-{Lambda} hyperfragments is possible at PANDA. In particular, we provide first theoretical estimations on the double-{Lambda} production cross section, which strongly rises with decreasing energy of the secondary {Xi}-beam.

Molecular single photon double K-shell ionization

International Nuclear Information System (INIS)

Penent, F.; Nakano, M.; Tashiro, M.; Grozdanov, T.P.; Žitnik, M.; Carniato, S.; Selles, P.; Andric, L.; Lablanquie, P.; Palaudoux, J.; Shigemasa, E.; Iwayama, H.; Hikosaka, Y.; Soejima, K.; Suzuki, I.H.; Kouchi, N.; Ito, K.

2014-01-01

We have studied single photon double K-shell ionization of small molecules (N 2 , CO, C 2 H 2n (n = 1–3), …) and the Auger decay of the resulting double core hole (DCH) molecular ions thanks to multi-electron coincidence spectroscopy using a magnetic bottle time-of-flight spectrometer. The relative cross-sections for single-site (K −2 ) and two-site (K −1 K −1 ) double K-shell ionization with respect to single K-shell (K −1 ) ionization have been measured that gives important information on the mechanisms of single photon double ionization. The spectroscopy of two-site (K −1 K −1 ) DCH states in the C 2 H 2n (n = 1–3) series shows important chemical shifts due to a strong dependence on the C-C bond length. In addition, the complete cascade Auger decay following single site (K −2 ) ionization has been obtained

Doubled haploid production from Spanish onion (Allium cepa L.) germplasm: embryogenesis induction, plant regeneration and chromosome doubling.

Science.gov (United States)

Fayos, Oreto; Vallés, María P; Garcés-Claver, Ana; Mallor, Cristina; Castillo, Ana M

2015-01-01

The use of doubled haploids in onion breeding is limited due to the low gynogenesis efficiency of this species. Gynogenesis capacity from Spanish germplasm, including the sweet cultivar Fuentes de Ebro, the highly pungent landrace BGHZ1354 and the two Valenciana type commercial varieties Recas and Rita, was evaluated and optimized in this study. The OH-1 population, characterized by a high gynogenesis induction, was used as control. Growing conditions of the donor plants were tested with a one-step protocol and field plants produced a slightly higher percentage of embryogenesis induction than growth chamber plants. A one-step protocol was compared with a two-step protocol for embryogenesis induction. Spanish germplasm produced a 2-3 times higher percentage of embryogenesis with the two-step protocol, Recas showing the highest percentage (2.09%) and Fuentes de Ebro the lowest (0.53%). These percentages were significantly lower than those from the OH-1 population, with an average of 15% independently of the protocol used. The effect of different containers on plant regeneration was tested using both protocols. The highest percentage of acclimated plants was obtained with the two-step protocol in combination with Eco2box (70%), whereas the lowest percentage was observed with glass tubes in the two protocols (20-23%). Different amiprofos-methyl (APM) treatments were applied to embryos for chromosome doubling. A similar number of doubled haploid plants were recovered with 25 or 50 μM APM in liquid medium. However, the application of 25 μM in solid medium for 24 h produced the highest number of doubled haploid plants. Somatic regeneration from flower buds of haploid and mixoploid plants proved to be a successful approach for chromosome doubling, since diploid plants were obtained from the four regenerated lines. In this study, doubled haploid plants were produced from the four Spanish cultivars, however further improvements are needed to increase their gynogenesis

Doubled haploid production from Spanish onion (Allium cepa L. germplasm: embryogenesis induction, plant regeneration and chromosome doubling

Directory of Open Access Journals (Sweden)

Oreto eFayos

2015-05-01

Full Text Available The use of doubled haploids in onion breeding is limited due to the low gynogenesis efficiency of this species. Gynogenesis capacity from Spanish germplasm, including the sweet cultivar Fuentes de Ebro, the highly pungent landrace BGHZ1354 and the two Valenciana type commercial varieties Recas and Rita, was evaluated and optimized in this study. The OH-1 population, characterized by a high gynogenesis induction, was used as control. Growing conditions of the donor plants were tested with a one-step protocol and field plants produced a slightly higher percentage of embryogenesis induction than growth chamber plants. A one-step protocol was compared with a two-step protocol for embryogenesis induction. Spanish germplasm produced a 2 to 3 times higher percentage of embryogenesis with the two-step protocol, Recas showing the highest percentage (2.09% and Fuentes de Ebro the lowest (0.53%. These percentages were significantly lower than those from the OH-1 population, with an average of 15% independently of the protocol used. The effect of different containers on plant regeneration was tested using both protocols. The highest percentage of acclimated plants was obtained with the two-step protocol in combination with Eco2box (70%, whereas the lowest percentage was observed with glass tubes in the two protocols (20-23%. Different amiprofos-methyl (APM treatments were applied to embryos for chromosome doubling. A similar number of doubled haploid plants were recovered with 25 or 50 µM APM in liquid medium. However, the application of 25 µM in solid medium for 24 h produced the highest number of doubled haploid plants. Somatic regeneration from flower buds of haploid and mixoploid plants proved to be a successful approach for chromosome doubling, since diploid plants were obtained from the 4 regenerated lines. In this study, doubled haploid plants were produced from the four Spanish cultivars, however further improvements are needed to increase their

DOUBLE STARS IN THE USNO CCD ASTROGRAPHIC CATALOG

Energy Technology Data Exchange (ETDEWEB)

Hartkopf, William I.; Mason, Brian D.; Finch, Charlie T.; Zacharias, Norbert; Wycoff, Gary L.; Hsu, Danley, E-mail: wih@usno.navy.mil, E-mail: bdm@usno.navy.mil, E-mail: finch@usno.navy.mil, E-mail: nz@usno.navy.mil [US Naval Observatory, Washington, DC 20392 (United States)

2013-10-01

The newly completed Fourth USNO CCD Astrographic Catalog (UCAC4) has proven to be a rich source of double star astrometry and photometry. Following initial comparisons of UCAC4 results against those obtained by speckle interferometry, the UCAC4 catalog was matched against known double stars in the Washington Double Star Catalog in order to provide additional differential astrometry and photometry for these pairs. Matches to 58,131 pairs yielded 61,895 astrometric and 68,935 photometric measurements. Finally, a search for possible new common proper motion (CPM) pairs was made using new UCAC4 proper motion data; this resulted in 4755 new potential CPM doubles (and an additional 27,718 astrometric and photometric measures from UCAC and other sources)

Double shell tank waste analysis plan

International Nuclear Information System (INIS)

Mulkey, C.H.; Jones, J.M.

1994-01-01

Waste analysis plan for the double shell tanks. SD-WM-EV-053 is Superseding SD-WM-EV-057.This document provides the plan for obtaining information needed for the safe waste handling and storage of waste in the Double Shell Tank Systems. In Particular it addresses analysis necessary to manage waste according to Washington Administrative Code 173-303 and Title 40, parts 264 and 265 of the Code of Federal Regulations

Double beta decay of 82Se

International Nuclear Information System (INIS)

Elliott, S.R.; Hahn, A.A.; Moe, M.K.; Nelson, M.A.; Vient, M.A.

1992-01-01

The two-neutrino double beta decay of 82 Se has been measured during a 20 244 h run resulting in a half-life of 1.08 -0.06 +0.26 x10 20 years (68% C.L.). No candidate events for the zero-neutrino double beta decay during 21 924 h results in a half-life limit of 2.7x10 22 years at the 68% confidence level

Cancer and central nervous system disorders: protocol for an umbrella review of systematic reviews and updated meta-analyses of observational studies.

Science.gov (United States)

Catalá-López, Ferrán; Hutton, Brian; Driver, Jane A; Page, Matthew J; Ridao, Manuel; Valderas, José M; Alonso-Arroyo, Adolfo; Forés-Martos, Jaume; Martínez, Salvador; Gènova-Maleras, Ricard; Macías-Saint-Gerons, Diego; Crespo-Facorro, Benedicto; Vieta, Eduard; Valencia, Alfonso; Tabarés-Seisdedos, Rafael

2017-04-04

The objective of this study will be to synthesize the epidemiological evidence and evaluate the validity of the associations between central nervous system disorders and the risk of developing or dying from cancer. We will perform an umbrella review of systematic reviews and conduct updated meta-analyses of observational studies (cohort and case-control) investigating the association between central nervous system disorders and the risk of developing or dying from any cancer or specific types of cancer. Searches involving PubMed/MEDLINE, EMBASE, SCOPUS and Web of Science will be used to identify systematic reviews and meta-analyses of observational studies. In addition, online databases will be checked for observational studies published outside the time frames of previous reviews. Eligible central nervous system disorders will be Alzheimer's disease, anorexia nervosa, amyotrophic lateral sclerosis, autism spectrum disorders, bipolar disorder, depression, Down's syndrome, epilepsy, Huntington's disease, multiple sclerosis, Parkinson's disease and schizophrenia. The primary outcomes will be cancer incidence and cancer mortality in association with a central nervous system disorder. Secondary outcome measures will be site-specific cancer incidence and mortality, respectively. Two reviewers will independently screen references identified by the literature search, as well as potentially relevant full-text articles. Data will be abstracted, and study quality/risk of bias will be appraised by two reviewers independently. Conflicts at all levels of screening and abstraction will be resolved through discussion. Random-effects meta-analyses of primary observational studies will be conducted where appropriate. Parameters for exploring statistical heterogeneity are pre-specified. The World Cancer Research Fund (WCRF)/American Institute for Cancer Research (AICR) criteria and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach will be used

Thermal effect on transverse vibrations of double-walled carbon nanotubes

International Nuclear Information System (INIS)

Zhang, Y Q; Liu, X; Liu, G R

2007-01-01

Based on the theory of thermal elasticity mechanics, a double-elastic beam model is developed for transverse vibrations of double-walled carbon nanotubes with large aspect ratios. The thermal effect is incorporated in the formulation. With this double-elastic beam model, explicit expressions are derived for natural frequencies and associated amplitude ratios of the inner to the outer tubes for the case of simply supported double-walled carbon nanotubes. The influence of temperature change on the properties of transverse vibrations is discussed. It is demonstrated that some properties of transverse vibrations of double-walled carbon nanotubes are dependent on the change of temperature

Double-compartment wrist arthrography

International Nuclear Information System (INIS)

Quinn, S.F.; Pittman, C.; Belsole, R.; Greene, T.L.; Rayhack, J.; Clark, R.A.; King, P.S.

1987-01-01

Seventy patients with clinical wrist problems were studied with double-compartment wrist arthrography. Midcarpal and radiocarpal compartment arthrograms were obtained in all patients. Digital subtraction technique was used to subtract out contrast from the first compartmental injection. Digital technique also allowed a dynamic record of each injection, which helped determine sites of intercompartmental communication. Postarthrography exercises recorded on videotape were performed after each injection. There were 34 normal studies. Abnormalities in the other 36 patients included: scapholunate communication (n = 9), lunatotriquetral communication (n = 6), communication with tendon sheaths (n = 4), communication with distal radioulnar compartment (n = 14), abnormal synovium process (n = 9), and communication through the radial or ulnar collateral ligament (n = 3). Double-compartment wrist arthrography may provide additional information for complex problems of the wrist

The double Laplacian growth

International Nuclear Information System (INIS)

Loutsenko, I.; Yermolayeva, O.

2008-06-01

The dynamics of the idealized Laplacian growth (or the Hele-Shaw problem) can be approximated by the Poiselle flow which in appropriate units takes the form of the Darcy law. In this paper we account for the liquid inertia in the Hele-Shaw problem at zero surface tension limit. The Laplace dynamics for the pressure is extended here with one more for the velocity potential for which we call this growth process the Double Laplacian. The application of the conformal mappings technique leads to doubled dynamics for both the conformal map and the complex potential, which is presented in the paper for the radial and the planar growth. We apply the stability analysis and discuss the integrability for the stated problem. (author)

Double-shell tank system dangerous waste permit application

International Nuclear Information System (INIS)

1991-06-01

This Double-Shell Tank System Dangerous Waste Permit Application should be read in conjunction with the 242-A Evaporator Dangerous Waste Permit Application and the Liquid Effluent Retention Facility Dangerous Waste Permit Application, also submitted on June 28, 1991. Information contained in the Double-Shell Tank System permit application is referenced in the other two permit applications. The Double-Shell Tank System stores and treats mixed waste received from a variety of sources on the Hanford Site. The 242-A Evaporator treats liquid mixed waste received from the double-shell tanks. The 242-A Evaporator returns a mixed-waste slurry to the double-shell tanks and generates the dilute mixed-waste stream stored in the Liquid Effluent Retention Facility. This report contains information on the following topics: Facility Description and General Provisions; Waste Characteristics; Process Information; Groundwater Monitoring; Procedures to Prevent Hazards; Contingency Plan; Personnel Training; Exposure Information Report; Waste Minimization Plan; Closure and Postclosure Requirements; Reporting and Recordkeeping; other Relevant Laws; and Certification. 150 refs., 141 figs., 118 tabs

Framework for evolution in double parton scattering

Energy Technology Data Exchange (ETDEWEB)

Buffing, Maarten G.A.

2017-07-15

Double parton scattering (DPS) describes two colliding hadrons having interactions in the form of two hard processes, each initiated by a separate pair of partons. Just as for single parton scattering, the resummation of soft gluon exchange gives rise to a soft function, which is a necessary ingredient for obtaining rapidity evolution equations. For various regions of phase space, we derive the rapidity evolution and the scale evolution of double transverse momentum dependent parton distribution functions (DTMDs) as well as of the p{sub T}-resummed cross section for double Drell-Yan like processes. This contributes to a framework that can be used for phenomenological DPS studies including resummation.

Single Photon Double Ionization of Atomic Oxygen

Science.gov (United States)

Wickramarathna, Madhushani; Gorczyca, Thomas; Ballance, Connor; Stolte, Wayne

2017-04-01

Single photon double ionization cross sections are calculated using an R-matrix with pseudostates (RMPS) method which was recently applied by Gorczyca et al. for the double photoionization of helium. With the convergence of these theoretical calculations for the simple case of helium, we extend this methodology to consider the more complex case of oxygen double photoionization. We compare our calculated results with recent measurements at the Advanced Light Source, as well as earlier experimental measurements. Our RMPS results agree well, qualitatively, with the experimental measurements, but there exist outstanding discrepancies to be addressed. This project is supported by NASA APRA award NNX17AD41G.

Singapore's double festival

Energy Technology Data Exchange (ETDEWEB)

Fraser, Gordon

1990-09-15

Coinciding with celebrations for the nation's 25th anniversary, the 25th International Conference on High Energy Physics, held in Singapore from 2-8 August, was itself a double festival, with the Standard Model of contemporary physics and CERN's new LEP electron-positron collider providing the twin themes.

Layered double hydroxides

DEFF Research Database (Denmark)

López Rayo, Sandra; Imran, Ahmad; Hansen, Hans Chr. Bruun

2017-01-01

A novel zinc (Zn) fertilizer concept based on Zn doped layered double hydroxides (Zn-doped Mg-Fe-LDHs) has been investigated. Zn-doped Mg-Fe-LDHs were synthetized, their chemical composition was analyzed and their nutrient release was studied in buffered solutions with different pH values. Uptake...

Laparoscopic cholecystectomy in double gallbladder with dual pathology

Directory of Open Access Journals (Sweden)

Sumanta Kumar Ghosh

2014-01-01

Full Text Available Double gallbladder is a rare embryological anomaly of clinical significance. Despite availability of modern imaging, only 50% of recently reported cases had preoperative diagnosis, which is desirable in every case to avoid serious operative complications. Double pathology in double gallbladder is extremely rare with only 3 reporting′s available till date to the best of author′s knowledge. With a preoperative diagnosis of double gallbladder, laparoscopic cholecystectomy can be safely and successfully performed with meticulous dissection, aided by operative cholangiogram. However in all such attempts a lower threshold should be kept for conversion to open surgery. Awareness about this anomaly amongst radiologists and surgeons is of crucial importance. Double gallbladder does not present with any specific symptom, neither it increases disease possibility in either lobe. Prophylactic cholecystectomy has no role in asymptomatic cases diagnosed accidentally. Author reports a case of a symptomatic young male with double gallbladder who presented with short history of dyspepsia, abdominal pain and fever. Definite preoperative diagnosis was reached with ultrasound scan and magnetic resonance cholangio pancreatography and subsequently dealt with laparoscopically. Calculous cholecystitis affected one lobe and acalculous empyema the other. While the 1st lobe drained though a cystic duct into common bile duct (CBD, the 2nd was without any communication with either CBD or its counterpart, thus remained as a blind vesicle.

Laparoscopic cholecystectomy in double gallbladder with dual pathology.

Science.gov (United States)

Ghosh, Sumanta Kumar

2014-04-01

Double gallbladder is a rare embryological anomaly of clinical significance. Despite availability of modern imaging, only 50% of recently reported cases had preoperative diagnosis, which is desirable in every case to avoid serious operative complications. Double pathology in double gallbladder is extremely rare with only 3 reporting's available till date to the best of author's knowledge. With a preoperative diagnosis of double gallbladder, laparoscopic cholecystectomy can be safely and successfully performed with meticulous dissection, aided by operative cholangiogram. However in all such attempts a lower threshold should be kept for conversion to open surgery. Awareness about this anomaly amongst radiologists and surgeons is of crucial importance. Double gallbladder does not present with any specific symptom, neither it increases disease possibility in either lobe. Prophylactic cholecystectomy has no role in asymptomatic cases diagnosed accidentally. Author reports a case of a symptomatic young male with double gallbladder who presented with short history of dyspepsia, abdominal pain and fever. Definite preoperative diagnosis was reached with ultrasound scan and magnetic resonance cholangio pancreatography and subsequently dealt with laparoscopically. Calculous cholecystitis affected one lobe and acalculous empyema the other. While the 1st lobe drained though a cystic duct into common bile duct (CBD), the 2nd was without any communication with either CBD or its counterpart, thus remained as a blind vesicle.

The double-contingency principle: An historical perspective

International Nuclear Information System (INIS)

Knief, R.A.

1995-01-01

Standard ANSI/ANS-8.1 states the double contingency principle as: Process designs should, in general, incorporate sufficient factors of safety to require at least two unlikely, independent, and concurrent changes in process conditions before a criticality accident is possible. This paper presents a perspective on the double contingency principle

40 CFR 721.5547 - Antimony double oxide.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Antimony double oxide. 721.5547 Section 721.5547 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.5547 Antimony double oxide. (a)...

Intrateam Communication and Performance in Doubles Tennis

Science.gov (United States)

Lausic, Domagoj; Tennebaum, Gershon; Eccles, David; Jeong, Allan; Johnson, Tristan

2009-01-01

Verbal and nonverbal communication is a critical mediator of performance in team sports and yet there is little extant research in sports that involves direct measures of communication. Our study explored communication within NCAA Division I female tennis doubles teams. Video and audio recordings of players during doubles tennis matches captured…

The Double-Deficit Hypothesis in Spanish Developmental Dyslexia

Science.gov (United States)

Jimenez, Juan E.; Hernandez-Valle, Isabel; Rodriguez, Cristina; Guzman, Remedios; Diaz, Alicia; Ortiz, Rosario

2008-01-01

The double-deficit hypothesis (DDH) of developmental dyslexia was investigated in seven to twelve year old Spanish children. It was observed that the double deficit (DD) group had the greatest difficulty with reading.

Application of international double taxation conventions in Romania

Directory of Open Access Journals (Sweden)

Florin Dumiter

2016-12-01

Full Text Available In this article we sought to address the international double taxation phenomenon from two different standpoints. To begin with, in the first part we analysed the framework of international double taxation, and how this topic was tackled in both Romanian and international literature.International double taxation has been analyzed, mutatis mutandis, from an economic perspective, more precisely in terms of the implications that it generates on economies, on added value, on capital flows, on the internationalisation of business. Second, I believed it was important to analyse international double taxation from a legal perspective, through the jurisdictional effects of obtaining income or holding property at the European or international level. Romania's case is carefully approached in this paper, aiming to highlight the issues Romania is facing concerning cooperation in tax matters with authorities from other countries, how the more than 80 double taxation conventions are applied and interpreted, but also other aspects that should be considered by the Romanian tax authorities, based on the provisions of the Fiscal Code and the Fiscal Procedure Code. The article ends by presenting, commenting on and analysing two test cases in international double taxation, of remarkable importance and actuality for Romanian jurisprudence to observe how complex double taxation mechanisms operate in practice. The conclusion of this article emphasises the importance ofsignificant “steps” achieved by Romania on the path to creating a true “fiscal area” in the European Union, as well as the “corridors” that should be inserted to correct economi c – legal and economic deficiencies and gaps, in order to strengthen the fiscal area.

The doubling of stellar black hole nuclei

Science.gov (United States)

Kazandjian, Mher V.; Touma, J. R.

2013-04-01

It is strongly believed that Andromeda's double nucleus signals a disc of stars revolving around its central supermassive black hole on eccentric Keplerian orbits with nearly aligned apsides. A self-consistent stellar dynamical origin for such apparently long-lived alignment has so far been lacking, with indications that cluster self-gravity is capable of sustaining such lopsided configurations if and when stimulated by external perturbations. Here, we present results of N-body simulations which show unstable counter-rotating stellar clusters around supermassive black holes saturating into uniformly precessing lopsided nuclei. The double nucleus in our featured experiment decomposes naturally into a thick eccentric disc of apo-apse aligned stars which is embedded in a lighter triaxial cluster. The eccentric disc reproduces key features of Keplerian disc models of Andromeda's double nucleus; the triaxial cluster has a distinctive kinematic signature which is evident in Hubble Space Telescope observations of Andromeda's double nucleus, and has been difficult to reproduce with Keplerian discs alone. Our simulations demonstrate how the combination of an eccentric disc and a triaxial cluster arises naturally when a star cluster accreted over a preexisting and counter-rotating disc of stars drives disc and cluster into a mutually destabilizing dance. Such accretion events are inherent to standard galaxy formation scenarios. They are here shown to double stellar black hole nuclei as they feed them.

Double gated-integrator for shaping nuclear radiation detector signals

International Nuclear Information System (INIS)

Gal, J.

2001-01-01

A new shaper, the double gated-integrator, for shaping nuclear radiation detector signals is investigated both theoretically and experimentally. The double gated-integrator consists of a pre-filter and two cascaded gated integrators. Two kinds of pre-filters were considered: a rectangular one and an exponential one. The results of the theoretical calculation show that the best figure of demerit for the double gated-integrator with exponential pre-filter is 1.016. This means that its noise to signal ratio is only 1.6% worse than that it is for infinite cusp shaping. The practical realization of the exponential pre-filter and that of the double gated integrator, both in analogue and in digital way, is very simple. Therefore, the double gated-integrator with exponential pre-filter could be a promising solution for shaping nuclear radiation detector signals

Double Marginalisation Effect Within Logistics Chain

OpenAIRE

Drago Pupavac

2008-01-01

Double marginalization occurs in vertical industries when both the upstream and downstream firms have monopoly power. Each firm reduces output from the competitive level to the monopoly level,creating two deadweight losses. This market myopia creates a "vertical externality" that vertical integration would internalize. In order to prove the hypothesis about building strategic partnership and collaboration as a way to remove the effect of double marginalization we have been focused on the rese...

Pion double charge exchange in the Δ33 resonance region

International Nuclear Information System (INIS)

Wirzba, A.; Toki, H.; Siciliano, E.R.; Johnson, M.B.; Gilman, R.

1989-01-01

We examine the model dependence and nuclear-structure sensitivity of several Δ 33 -dominated processes contributing to pion double charge exchange on nuclei in the region of the Δ 33 resonance. These processes include the Δ 33 -nucleon interaction V NΔ and sequential scattering, in which the pion undergoes single charge exchange on two different nucleons. In all cases, the scattering takes place through the exchange of an intermediate π and ρ meson. Sequential-mediated double charge exchange is found to be only moderately sensitive to short-range correlations, meson-nucleon form factors, and the rho meson, whereas V NΔ -mediated double charge exchange is very sensitive to all these effects. Results are given for double charge exchange on 18 O (double isobaric analog transitions) and 16 O (nonanalog transitions). Sequential double charge exchange is shown to favor non-spin-flip matrix elements of the transition operator whereas V NΔ -mediated double charge exchange favors spin-flip matrix elements. The energy dependence of the zero-degree cross sections for V NΔ and sequential scattering are also different: Sequential tends to increase monotonically from 100 to 300 MeV, whereas V NΔ peaks at about 150 MeV. The delta-nucleon interaction is found likely to dominate over sequential scattering in nonanalog double charge exchange. The V NΔ is also large in analog double charge exchange, but it does not enable us to explain the anomalous behavior of the 18 O differential cross sections

Double-partition Quantum Cluster Algebras

DEFF Research Database (Denmark)

Jakobsen, Hans Plesner; Zhang, Hechun

2012-01-01

A family of quantum cluster algebras is introduced and studied. In general, these algebras are new, but sub-classes have been studied previously by other authors. The algebras are indexed by double parti- tions or double flag varieties. Equivalently, they are indexed by broken lines L. By grouping...... together neighboring mutations into quantum line mutations we can mutate from the cluster algebra of one broken line to another. Compatible pairs can be written down. The algebras are equal to their upper cluster algebras. The variables of the quantum seeds are given by elements of the dual canonical basis....

Maxillary double lip: A case series with review of literature

Directory of Open Access Journals (Sweden)

Vela D Desai

2015-01-01

Full Text Available Double lip is a rare dental anomaly affecting either upper or lower lip or concurrently. It may be congenital or acquired. This deformity can affect the facial esthetics as it gets exaggerated while speaking, smiling, or chewing food. When it interferes with speech, double lip may cause potential functional problems. The purpose of this article is to review the literature on double lip and present a case series of maxillary double lip.

Caught without an Umbrella

DEFF Research Database (Denmark)

Kusk, Hanne; Svendsen, Sonja

2013-01-01

and engaged mind to aesthetic work. Being capable of creating inspiring, physical and mental frames has a crucial significance for developing aesthetic contents and expression in drama pedagogy. Being teachers on the social education line at VIA University College and knowledge employees at Knowledge Center...... for Children and Youngsters, we have experience in working with two drama aesthetical projects. Sonja Svendsen with focus on the influence frameworking has, in order to involve the participants as co-creators of an aesthetic expression. Hanne Kusk with focus on the attunement concept and which influence......An aesthetic perspective on frameworking and attunement in a drama pedagogical practice. How do attunement moments arise? Can they be planned and frameworked? What characterizes good frames? What does it require from the teacher, and how can we use framework and attunement? Attunement means an open...

OH spectroscopy with frequency-doubled dye laser radiation

Energy Technology Data Exchange (ETDEWEB)

ter Meulen, J J

1979-01-01

Discusses the excitation of the OH radical by UV radiation for the determination of the hyperfine structure of the excited states. The 307 nm UV light is obtained by doubling the frequency (in double-refraction crystals) of a tunable dye laser. Details of the laser set-up are given. The method is suitable for application to other high-resolution molecular spectroscopy experiments in the area between 200 and 400 nm. Further extensions can be expected with ring compound dyes and external doubling of the frequency.

Double charge exchange of pions on nuclei

International Nuclear Information System (INIS)

Dzhibuti, R.I.; Kezerashvili, R.Y.

1985-01-01

An analysis is made of the results of experimental and theoretical studies during the last ten years of a unique process: double charge exchange of pions on nuclei. On the one hand, the commissioning of meson factories and the use of new and more accurate experimental methods have led to the accumulation of rich and reliable material for not only light but also medium and heavy nuclei. On the other hand, the development and application of new microscopic theoretical approaches have led to a deepening of our ideas about the mechanism of these exotic reactions at low, intermediate, and high energies. The currently existing methods of theoretical investigation and all possible reaction mechanisms are considered. Particular attention is devoted to double charge exchange of pions on the lightest nuclei, for the theoretical description of which it is possible to use the well-developed methods for investigating few-particle systems. The experimental investigations of double-isobar analog and nonanalog transitions in the reaction of double charge exchange are systematized

[Euthanasia and the doctrine of double effect].

Science.gov (United States)

Klein, Martin

2005-01-01

Direct active euthanasia is prohibited in most countries while passive and indirect is not. However, many arguments against the legalization of voluntary active euthanasia are flawed. Ethical differences between active and passive or indirect euthanasia are difficult to maintain especially when the passivity of the actor causes death. The crucial point is not activity or passivity but respect for the autonomy of individual human beings. In particular there appears to be little ethical difference between active and indirect euthanasia. Indirect euthanasia has often been justified by the principle of double effect, which traces back to Thomas Aquinas. But resorting to this rule contains a logical fallacy. The principle of double effect does not allow foreseen and unwanted adverse effects of an action to occur when they are avoidable. In terminal sedation, an example for indirect euthanasia, hypoxemia and dehydration can easily be prevented by respirator therapy and fluid administration. Therefore the rule of double effect is not applicable. Indirect and direct active euthanasia cannot be ethically distinguished by resorting to the principle of double effect.

An exactly soluble model of a shallow double well

Energy Technology Data Exchange (ETDEWEB)

Muñoz-Vega, R., E-mail: rodrigo.munoz@uacm.edu.mx [Universidad Autónoma de la Ciudad de México, Centro Histórico, Fray Servando Teresa de Mier 92, Col. Centro, Del. Cuauhtémoc, México DF, CP 06080 (Mexico); López-Chávez, E., E-mail: elopezc@hotmail.com [Universidad Autónoma de la Ciudad de México, Centro Histórico, Fray Servando Teresa de Mier 92, Col. Centro, Del. Cuauhtémoc, México DF, CP 06080 (Mexico); Salinas-Hernández, E., E-mail: esalinas@ipn.mx [ESCOM-IPN, Av Juan de Dios Bátiz s/n, Unidad Profesional Adolfo López Mateos, Col Lindavista, Del G A Madero, México DF, CP 07738 (Mexico); Flores-Godoy, J.-J., E-mail: job.flores@ibero.mx [Departamento de Física y Matemáticas, Universidad Iberoamericana, Prol. Paseo de la Reforma 880, Col Lomas de Santa Fe, Del A Obregón, México DF, CP 01219 (Mexico); Fernández-Anaya, G., E-mail: guillermo.fernandez@ibero.com [Departamento de Física y Matemáticas, Universidad Iberoamericana, Prol. Paseo de la Reforma 880, Col Lomas de Santa Fe, Del A Obregón, México DF, CP 01219 (Mexico)

2014-06-13

Shallow one-dimensional double-well potentials appear in atomic and molecular physics and other fields. Unlike the “deep” wells of macroscopic quantum coherent systems, shallow double wells need not present low-lying two-level systems. We argue that this feature, the absence of a low-lying two-level system in certain shallow double wells, may allow the finding of new test grounds for quantum mechanics in mesoscopic systems. We illustrate the above ideas with a family of shallow double wells obtained from reflectionless potentials through the Darboux–Bäcklund transform. - Highlights: • We present double wells not conforming to the low-lying two-state system model. • Models similar to ours appear in atomic and molecular physics. • Here there is no classically prohibited region between wells. • The ground probability is peaked at the position of classical unstable equilibrium in this models.

Single- and double-charge exchange at low pion energies

International Nuclear Information System (INIS)

Baer, H.W.

1991-01-01

A review is given of pion single- and double-charge exchange reactions at incident energies of 25 to 65 MeV leading to isobaric analog states, and in the case of double-charge exchange leading to the ground state of the residual nucleus. The crucial role of the higher nuclear transparency at low pion energies for the analysis of the data in terms of single and double scattering is demonstrated. The large effects on double-charge exchange produced by the spatial correlations in nuclear wave functions are evident. The data on 1f 7/2 nuclei at 35 MeV are used to establish the general validity of a shell-model-based two-amplitude model for these transitions. Recent measurements of the energy dependence between 25 and 65 MeV of double-charge exchange cross sections at forward angles are presented and discussed. 33 refs., 19 figs

Ultrasonic Characterization of Water Saturated Double Porosity Media

Science.gov (United States)

Bai, Ruonan; Tinel, Alain; Alem, Abdellah; Franklin, Hervé; Wang, Huaqing

Wave propagation through a multilayered structure consisting of a water saturated double porosity medium in an aluminum rectangular box immersed in water is studied. By assuming a plane incident wave from water onto the structure, the reflection and transmission coefficients are derived by application of the boundary conditions at each interface. Numerical computations are done for two particular double porosity media, ROBU® and Tobermorite 11 Å, that are assumed to obey Berryman's extension of Biot's theory [Berryman 1995, 2000]. The influence of the thickness of double porosity medium is investigated. To compare experiments to computations, two comparison coefficients Cnum and Cexp are introduced. The theoretical one Cnum is defined as the ratio of the transmission coefficient of the structure to the transmission coefficient of the box filled exclusively with water. The experimental comparison coefficient Cexp is defined as the ratio of the Fourier transforms of the transmitted signals by the box filled with the double porous medium to that of the transmitted signals by the box filled with water. A method of minimization based on a gradient descent algorithm is used to optimize some of the parameters of the double porosity media such as the bulk moduli.

NIF Double Shell outer/inner shell collision experiments

Science.gov (United States)

Merritt, E. C.; Loomis, E. N.; Wilson, D. C.; Cardenas, T.; Montgomery, D. S.; Daughton, W. S.; Dodd, E. S.; Desjardins, T.; Renner, D. B.; Palaniyappan, S.; Batha, S. H.; Khan, S. F.; Smalyuk, V.; Ping, Y.; Amendt, P.; Schoff, M.; Hoppe, M.

2017-10-01

Double shell capsules are a potential low convergence path to substantial alpha-heating and ignition on NIF, since they are predicted to ignite and burn at relatively low temperatures via volume ignition. Current LANL NIF double shell designs consist of a low-Z ablator, low-density foam cushion, and high-Z inner shell with liquid DT fill. Central to the Double Shell concept is kinetic energy transfer from the outer to inner shell via collision. The collision determines maximum energy available for compression and implosion shape of the fuel. We present results of a NIF shape-transfer study: two experiments comparing shape and trajectory of the outer and inner shells at post-collision times. An outer-shell-only target shot measured the no-impact shell conditions, while an `imaging' double shell shot measured shell conditions with impact. The `imaging' target uses a low-Z inner shell and is designed to perform in similar collision physics space to a high-Z double shell but can be radiographed at 16keV, near the viable 2DConA BL energy limit. Work conducted under the auspices of the U.S. DOE by LANL under contract DE-AC52-06NA25396.

Finite difference order doubling in two dimensions

International Nuclear Information System (INIS)

Killingbeck, John P; Jolicard, Georges

2008-01-01

An order doubling process previously used to obtain eighth-order eigenvalues from the fourth-order Numerov method is applied to the perturbed oscillator in two dimensions. A simple method of obtaining high order finite difference operators is reported and an odd parity boundary condition is found to be effective in facilitating the smooth operation of the order doubling process

Ion-acoustic solitary waves near double layers

International Nuclear Information System (INIS)

Kuehl, H.H.; Imen, K.

1985-01-01

The possibility of ion-acoustic solitary-wave solutions in the uniform plasma on the high-potential side of double layer is investigated. Based on a fluid model of the double layer, it is found that both compressive and rarefactive solitary waves are allowed. Curves are presented which show the regions in parameter space in which these solutions exist

Double layer formed by beam driven ion-acoustic turbulence

International Nuclear Information System (INIS)

Ludwig, G.O.; Ferreira, J.L.; Montes, A.

1987-08-01

Small amplitudes steady-state ion-acoustic double layers are observed to form in a plasma transversed by a beam of cold electrons. The importance of turbulence in maintaining the double layer is demonstrated. The measured wave spectrum is in approximate agreement with models deriveted from renornalized turbulence theory. The general features of the double layer are compared with results from particle simulation studies. (author) [pt

The classical double copy for Taub–NUT spacetime

Energy Technology Data Exchange (ETDEWEB)

Luna, Andrés, E-mail: a.luna-godoy.1@research.gla.ac.uk [School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, Scotland (United Kingdom); Monteiro, Ricardo, E-mail: monteiro@maths.ox.ac.uk [Mathematical Institute, University of Oxford, Oxford OX2 6GG, England (United Kingdom); O' Connell, Donal, E-mail: donal@staffmail.ed.ac.uk [Higgs Centre for Theoretical Physics, School of Physics and Astronomy, The University of Edinburgh, Edinburgh EH9 3JZ, Scotland (United Kingdom); Kavli Institute for Theoretical Physics, University of California, Santa Barbara, CA 93106-4030 (United States); White, Chris D., E-mail: Christopher.White@glasgow.ac.uk [School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, Scotland (United Kingdom)

2015-11-12

The double copy is a much-studied relationship between gauge theory and gravity amplitudes. Recently, this was generalised to an infinite family of classical solutions to Einstein's equations, namely stationary Kerr–Schild geometries. In this paper, we extend this to the Taub–NUT solution in gravity, which has a double Kerr–Schild form. The single copy of this solution is a dyon, whose electric and magnetic charges are related to the mass and NUT charge in the gravity theory. Finally, we find hints that the classical double copy extends to curved background geometries.

Neutrinoless double beta decay

Indian Academy of Sciences (India)

2012-10-06

Oct 6, 2012 ... Anyhow, the 'multi-isotope' ansatz is needed to compensate for matrix element ... The neccessary half-life requirement to touch this ... site energy depositions (like double beta decay) and multiple site interactions (most of.

Single versus double-row repair of the rotator cuff: does double-row repair with improved anatomical and biomechanical characteristics lead to better clinical outcome?

Science.gov (United States)

Pauly, Stephan; Gerhardt, Christian; Chen, Jianhai; Scheibel, Markus

2010-12-01

Several techniques for arthroscopic repair of rotator cuff defects have been introduced over the past years. Besides established techniques such as single-row repairs, new techniques such as double-row reconstructions have gained increasing interest. The present article therefore provides an overview of the currently available literature on both repair techniques with respect to several anatomical, biomechanical, clinical and structural endpoints. Systematic literature review of biomechanical, clinical and radiographic studies investigating or comparing single- and double-row techniques. These results were evaluated and compared to provide an overview on benefits and drawbacks of the respective repair type. Reconstructions of the tendon-to-bone unit for full-thickness tears in either single- or double-row technique differ with respect to several endpoints. Double-row repair techniques provide more anatomical reconstructions of the footprint and superior initial biomechanical characteristics when compared to single-row repair. With regard to clinical results, no significant differences were found while radiological data suggest a better structural tendon integrity following double-row fixation. Presently published clinical studies cannot emphasize a clearly superior technique at this time. Available biomechanical studies are in favour of double-row repair. Radiographic studies suggest a beneficial effect of double-row reconstruction on structural integrity of the reattached tendon or reduced recurrent defect rates, respectively.

Double radio sources and the new approach to cosmic plasma physics

International Nuclear Information System (INIS)

Alfven, H.

1977-08-01

The methodology of cosmic plasma physics is discussed. A summary is given of laboratory investigations of electric double layers, a phenomenon which is known to be very important in laboratory discharges. The importance of electric double layers in the Earth's surrounding is established. The scaling laws between laboratory and magnetospheric double layers are studied. A further extrapolation to galactic phenomena leads to a theory of double radio sources. From analogy with laboratory and magnetospheric current systems it is argued that the galactic current might produce double layers where a large energy dissipation takes place. This leads to a theory of the double radio sources which within the necessary wide limits of uncertainty is quantitatively reconcilable with observations. (author)

Effects of Tamsulosin and Tolterodine on double J stent–related symptoms: A double-blind, randomized, placebo-controlled trial

Directory of Open Access Journals (Sweden)

Mahmoudreza Moradi

2017-02-01

Full Text Available Background: Ureteral double J stent are routinely applied for urologic patients although stent-related symptoms are common. Several attempts have been reported to minimize these symptoms. Objective: To compare Tolterodine, Tamsulosin, and placebo effects on double J stent–related symptoms. Material and method: In all, 125 patients (82 males and 43 females with double J stent were randomly divided into three groups (group 1, n: 42, group2, n: 40 and group 3, n: 43. Each patient randomly received one pack of drug in different colors by a nurse unaware of the content to take Tamsulosin 0.4 mg before sleep (MODALUSINE, Tolterodine 2 mg twice a day or placebo once daily (capsules filled with starch: group 1 received placebo, group 2 Tamsulosin and group 3 Tolterodine for 1 month in a double-blind manner. Ureteral stent-related morbidity indices which analyzed include urinary symptom, pain, general health, quality of work and sex scores. All of indices measured by Ureteral Symptom Score Questionnaire for first and fourth weeks after drug consumption and the first week after double J stent removal (labeled as w1, w4, and w5, respectively. Result: The mean age was 44.8 years (range: 15–83 years. There was no statistically significant difference in background characteristics between groups (p value > 0.05. The most important and statistically significant results were Tolterodine-reduced urinary symptom score (p value = 0.001 and improved general health score (p value = 0.007 of the fourth week. The pain score in groups of Tamsulosin and Tolterodine significantly reduced between weeks 4 and 1 and 5 and 1 (both with the p value < 0.05, but in other indices, there was no significant difference between them. Conclusion: According to our results, we suggest Tolterodine to minimize stent-related urinary symptom and improve general health in patients with double J stent.

Double Tracks revegetation and monitoring plan

International Nuclear Information System (INIS)

1997-07-01

This document is a reclamation plan for short-term and long-term stabilization of land disturbed by activities associated with interim clean-up of radionuclide-contaminated surface soil at the Double Tracks site. This document has been prepared to provide general reclamation practices and procedures that will be followed during restoration of the cleanup site. Reclamation demonstration plots were established near the site in the fall of 1994 to evaluate the performance of several native species and to evaluate different irrigation strategies. Results of the study at Double Tracks, as well as the results from numerous studies conducted at other sites (Area 11 and Area 19 of the Nevada Test Site), have been summarized and incorporated into this final reclamation plan for the interim cleanup of the Double Tracks site, located northwest of the Nevada Test Site on the Nellis Air Force Range. Surface soils at Double Tracks were contaminated as a result of the detonation of a device containing plutonium and depleted uranium using chemical explosives. The total amount of Pu deposited on the site was between 980 and 1,600 grams and was scattered downwind south of the detonation site. Short-term stabilization consists of the application of a chemical soil stabilizer that is applied immediately following excavation of the contaminated soils to minimize Pu resuspension. Long-term stabilization is accomplished by the establishment of a permanent vegetation

21 CFR 172.330 - Calcium pantothenate, calcium chloride double salt.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Calcium pantothenate, calcium chloride double salt... FOOD FOR HUMAN CONSUMPTION Special Dietary and Nutritional Additives § 172.330 Calcium pantothenate, calcium chloride double salt. The food additive calcium chloride double salt of calcium pantothenate may...

On efficiency of some ratio estimators in double sampling design ...

African Journals Online (AJOL)

In this paper, three sampling ratio estimators in double sampling design were proposed with the intention of finding an alternative double sampling design estimator to the conventional ratio estimator in double sampling design discussed by Cochran (1997), Okafor (2002) , Raj (1972) and Raj and Chandhok (1999).

Characterizations of double pulsing in neutron multiplicity and coincidence counting systems

Energy Technology Data Exchange (ETDEWEB)

Koehler, Katrina E., E-mail: kkoehler@lanl.gov [Los Alamos National Laboratory, P. O. Box 1663, Los Alamos, NM 87545 (United States); Henzl, Vladimir [Los Alamos National Laboratory, P. O. Box 1663, Los Alamos, NM 87545 (United States); Croft, Stephen S. [Oak Ridge National Laboratory, 1 Bethel Valley Rd, Oak Ridge, TN 37831 (United States); Henzlova, Daniela; Santi, Peter A. [Los Alamos National Laboratory, P. O. Box 1663, Los Alamos, NM 87545 (United States)

2016-10-01

Passive neutron coincidence/multiplicity counters are subject to non-ideal behavior, such as double pulsing and dead time. It has been shown in the past that double-pulsing exhibits a distinct signature in a Rossi-alpha distribution, which is not readily noticed using traditional Multiplicity Shift Register analysis. However, it has been assumed that the use of a pre-delay in shift register analysis removes any effects of double pulsing. In this work, we use high-fidelity simulations accompanied by experimental measurements to study the effects of double pulsing on multiplicity rates. By exploiting the information from the double pulsing signature peak observable in the Rossi-alpha distribution, the double pulsing fraction can be determined. Algebraic correction factors for the multiplicity rates in terms of the double pulsing fraction have been developed. We discuss the role of these corrections across a range of scenarios.

Development of double-pair double difference location algorithm and its application to the regular earthquakes and non-volcanic tremors

Science.gov (United States)

Guo, H.; Zhang, H.

2016-12-01

Relocating high-precision earthquakes is a central task for monitoring earthquakes and studying the structure of earth's interior. The most popular location method is the event-pair double-difference (DD) relative location method, which uses the catalog and/or more accurate waveform cross-correlation (WCC) differential times from event pairs with small inter-event separations to the common stations to reduce the effect of the velocity uncertainties outside the source region. Similarly, Zhang et al. [2010] developed a station-pair DD location method which uses the differential times from common events to pairs of stations to reduce the effect of the velocity uncertainties near the source region, to relocate the non-volcanic tremors (NVT) beneath the San Andreas Fault (SAF). To utilize advantages of both DD location methods, we have proposed and developed a new double-pair DD location method to use the differential times from pairs of events to pairs of stations. The new method can remove the event origin time and station correction terms from the inversion system and cancel out the effects of the velocity uncertainties near and outside the source region simultaneously. We tested and applied the new method on the northern California regular earthquakes to validate its performance. In comparison, among three DD location methods, the new double-pair DD method can determine more accurate relative locations and the station-pair DD method can better improve the absolute locations. Thus, we further proposed a new location strategy combining station-pair and double-pair differential times to determine accurate absolute and relative locations at the same time. For NVTs, it is difficult to pick the first arrivals and derive the WCC event-pair differential times, thus the general practice is to measure station-pair envelope WCC differential times. However, station-pair tremor locations are scattered due to the low-precision relative locations. The ability that double-pair data

Double beta decay: experiments

International Nuclear Information System (INIS)

Fiorini, Ettore

2006-01-01

The results obtained so far and those of the running experiments on neutrinoless double beta decay are reviewed. The plans for second generation experiments, the techniques to be adopted and the expected sensitivities are compared and discussed

Search for neutrinoless double-electron capture of 156Dy

Science.gov (United States)

Finch, S. W.; Tornow, W.

2015-12-01

Background: Multiple large collaborations are currently searching for neutrinoless double-β decay, with the ultimate goal of differentiating the Majorana-Dirac nature of the neutrino. Purpose: Investigate the feasibility of resonant neutrinoless double-electron capture, an experimental alternative to neutrinoless double-β decay. Method: Two clover germanium detectors were operated underground in coincidence to search for the de-excitation γ rays of 156Gd following the neutrinoless double-electron capture of 156Dy. 231.95 d of data were collected at the Kimballton underground research facility with a 231.57 mg enriched 156Dy sample. Results: No counts were seen above background and half-life limits are set at O (1016-1018) yr for the various decay modes of 156Dy. Conclusion: Low background spectra were efficiently collected in the search for neutrinoless double-electron capture of 156Dy, although the low natural abundance and associated lack of large quantities of enriched samples hinders the experimental reach.

Self-assembly of a double-helical complex of sodium.

Science.gov (United States)

Bell, T W; Jousselin, H

1994-02-03

Spontaneous self-organization of helical and multiple-helical molecular structures occurs on several levels in living organisms. Key examples are alpha-helical polypeptides, double-helical nucleic acids and helical protein structures, including F-actin, microtubules and the protein sheath of the tobacco mosaic virus. Although the self-assembly of double-helical transition-metal complexes bears some resemblance to the molecular organization of double-stranded DNA, selection between monohelical, double-helical and triple-helical structures is determined largely by the size and geometrical preference of the tightly bound metal. Here we present an example of double-helical assembly induced by the weaker and non-directional interactions of an alkali-metal ion with an organic ligand that is pre-organized into a coil. We have characterized the resulting complex by two-dimensional NMR and fast-atom-bombardment mass spectrometry. These results provide a step toward the creation of molecular tubes or ion channels consisting of intertwined coils.

Irradiation of parametria by double-wedge

International Nuclear Information System (INIS)

Weisz, Csaba; Katona, Ernoe; Zarand, Pal; Polgar, Istvan; Nemeth, Gyoergy

1984-01-01

The dose distribution of a cobalt unit modified with a double-wedge as well as its combination with intracavitary radiotherapy was investigated. The measurements were made in both Alderson-Rando and wather phantom by using film densitometry, thermoluminescence dosimetry and ionization chambers. The dose distribution calculated on the basis of the Van de Geij program was in good agreement with the measurements. A homogeneous irradiation of the parametria can be obtained by using a combination of intracavitary and external double-wedge irradiation. (author)

Double Harmonic Transmission (D.H.T.

Directory of Open Access Journals (Sweden)

Sava Ianici

2006-10-01

Full Text Available The paper presents the construction and functioning of a new type of harmonic drive named double harmonic transmission (D.H.T.. In the second part of this paper is presented the dynamic analysis of the double harmonic transmission, which is based on the results of the experimental researches on the D.H.T. This study of the stress status and the forces distribution is necessary for to determine the durability on the portant elements of the D.H.T.

Double Skin Facades for Office Buildings. Literature Review

Energy Technology Data Exchange (ETDEWEB)

Poirazis, Harris

2004-07-01

The aim of this report is to describe the concept of Double Skin Facades based on different sources of literature. Although the concept is not new, there is a growing tendency from the architects to put it into practice. Its complexity and adaptability to different climatic conditions increase the need for careful design. Since the construction types can differ from one location to another, it is obvious that the comparison of different literature sources is not always relevant. Since the concept of Double Skin Facades is complicated and its use and function affects different parameters of the building, the literature studied is from different fields. It is clear that the design of the system is crucial for the performance of the building. It is the opinion of the author that the Double Skin Facades can provide both improved indoor climate and reduced use of energy in the same time if designed properly. If the approach is overall and the goals to be achieved are clear, then the mentioned system is flexible enough to meet climatic changes for most types of building use. The classification of the Double Skin Facades is important since the initial approach can influence the design stage. After selecting the type of Double Facade appropriate for the building, it is necessary to define the design and the technical parameters (such as the materials used) that can influence the function and the performance of the system and the physical properties of the cavity. The accuracy of calculations of the facade performance in the design stage will lead to more precise predictions. It is clear that by prioritizing the main goals of the double facade system in different ways, the building design and construction can differ adapting to the performance requirements of the designers, and the needs of the users. The advantages and disadvantages of double skin facades found in different literature sources are mentioned and described. Furthermore, examples of office buildings with

Oromandibular reconstruction with chimeric double-skin paddle flap based on peroneal vessel axis for synchronous opposite double oral cancer.

Science.gov (United States)

Huang, Shih-Tsai; Liu, Wen-Chung; Chen, Lee-Wei; Yang, Kuo-Chung

2015-05-01

Synchronous double oral cancer represents the minority of cases of head and neck cancer. After tumor ablation, 2 separate oromandibular defects, even combined with a through-and-through oral defect, pose a serious reconstructive challenge. The ideal method for reconstruction remains controversial. Based on the peroneal vessel axis, a chimeric double-skin paddle peroneal fasciocutaneous or fibular osteomyocutaneous flap could be designed to accomplish the difficult reconstruction. Six male patients, each with 2 separate oromandibular defects after tumor ablation of synchronous double oral cancer, received double-skin paddle flap reconstruction with 3 peroneal fasciocutaneous and 3 fibular osteomyocutaneous flaps. All 6 flaps survived; however, complications included 1 skin paddle lost due to insufficient perfusion of a visible perforator, and 1 superficial necrosis occurring over the tip of a longer skin paddle. One postoperative intraoral infection and 1 donor site infection were also reported. During follow-up, 3 months later, 1 patient succumbed to local recurrence and bony metastasis. One patient developed a new cancer in the maxillary gingiva, and another had osteoradionecrosis 8 months later. Four patients gained acceptable cosmesis with good oral competence. A chimeric flap based on the peroneal artery could provide a segment of fibular bone, 1 or 2 skin paddles, and a cuff of the flexor hallucis longus muscle simultaneously. For 1-stage reconstruction of separate oromandibular defects after tumor ablation of synchronous double oral cancer, this design could provide all components at 1 transfer.

WKB corrections to the energy splitting in double-well potentials

OpenAIRE

Robnik, Marko; Salasnich, Luca

1997-01-01

By using the WKB quantization we deduce an analytical formula for the energy splitting in a double-well potential which is the usual Landau formula with additional quantum corrections. Then we analyze the accuracy of our formula for the double square well potential and the parabolic double-well potential.

Experiments on ion acoustic typed double layers

International Nuclear Information System (INIS)

Chan, C.; Cho, M.H.; Intrator, T.; Hershkowitz, N.

1984-01-01

The formation of small amplitude double layers with potential drops the order of the electron temperature, was examined experimentally by pulsing a grid and thereby changing the electron drift across the target chamber of a triple plasma device. The rarefactive part of a long wavelength, low frequency ion wave grew in amplitude due to the presence of slowly drifting electrons. The corresponding current limitation led to the formation of the double layers. Depending on the plasma conditions, the asymmetric double layers either transform into a weak monotonic layer, a propagating shock, or a series of rarefactive solitary pulses. The rarefactive pulses propagate with Mach number less than one and resemble solitary plasma holes with density cavities in both the electron and the ion density profiles

Double shell tanks emergency pumping plan

International Nuclear Information System (INIS)

Tangen, M.J.

1994-01-01

At the request of the Department of Energy (DOE), a formal plan for the emergency transfer of waste from a leaking double shell tank to a designated receiver tank has been developed. This plan is in response to the priority 2 safety issue ''Response to a leaking double-shell tank'' in the DOE Report to Congress, 1991. The plan includes the tanks in four of the east tank farms and one of the west farms. The background information and supporting calculations used for the creation of the emergency plan are discussed in this document. The scope of this document is all of the double shell tanks in the AN, AP, AW, AY, and SY farms. The transfer lines, flush pits, and valve pits involved in the transfer of waste between these farms are also included in the scope. Due to the storage of high heat waste, AZ farm is excluded at this time

Mechanical response of biopolymer double networks

Science.gov (United States)

Carroll, Joshua; Das, Moumita

We investigate a double network model of articular cartilage (AC) and characterize its equilibrium mechanical response. AC has very few cells and the extracellular matrix mainly determines its mechanical response. This matrix can be thought of as a double polymer network made of collagen and aggrecan. The collagen fibers are stiff and resist tension and compression forces, while aggrecans are flexible and control swelling and hydration. We construct a microscopic model made of two interconnected disordered polymer networks, with fiber elasticity chosen to qualitatively mimic the experimental system. We study the collective mechanical response of this double network as a function of the concentration and stiffness of the individual components as well as the strength of the connection between them using rigidity percolation theory. Our results may provide a better understanding of mechanisms underlying the mechanical resilience of AC, and more broadly may also lead to new perspectives on the mechanical response of multicomponent soft materials. This work was partially supported by a Cottrell College Science Award.

Relativistic pn-QRPA to the double beta decay

International Nuclear Information System (INIS)

Conti, Claudio de; Krmpotic, F.; Carlson, Brett Vern

2010-01-01

Full text: In nature there are about 50 nuclear systems where the single beta-decay is energetically forbidden, and double- beta decay turns out to be only possible mode of disintegration. It is the nuclear pairing force which causes such an 'anomaly', by making the mass of the odd-odd isobar, (N - 1;Z + 1), to be greater than the masses of its even-even neighbors, (N;Z) and (N - 2;Z +2). The modes by which the double-beta decay can take place are connected with the neutrino and antineutrino distinction. In case the lepton number is strictly conserved the neutrino is a Dirac fermion and the two-neutrino mode is the only possible mode of disintegration. On the other hand, if this conservation is violated, the neutrino is a Majorana particle and neutrinoless double-beta decay also can occur. Both two-neutrino and neutrinoless double-beta decay processes have attracted much attention, because a comparison between experiment and theory for the first, provides a measure of confidence one may have in the nuclear wave function employed for extracting the unknown parameters from neutrinoless lifetime measurements. The proton-neutron (pn) quasiparticle random phase approximation (QRPA) has turned out be the most simple model for calculating the nuclear wave function involved in the double-beta decay transitions. In this work the transition matrix elements for 0 + -> 0 + double-beta decay are calculated for 48 Ca, 76 Ge, 82 Se, 100 Mo, 128 Te and 130 Te nuclei, using a relativistic pn-QRPA based on Hartree-Bogoliubov approximation to the single-particle motion. (author)

Spontaneous mutation rates and the rate-doubling dose

International Nuclear Information System (INIS)

Von Borstel, R.C.; Moustaccki, E.; Latarjet, R.

1978-01-01

The amount of radiation required to double the frequency of mutations or tumours over the rate of those that occur spontaneously is called the rate-doubling dose. An equivalent concept has been proposed for exposure to other environmental mutagens. The doubling dose concept is predicated on the assumption that all human populations have the same spontaneous mutation rate, and that this spontaneous mutation rate is known. It is now established for prokaryotes and lower eukaryotes that numerous genes control the spontaneous mutation rate, and it is likely that the same is true for human cells as well. Given that the accepted mode of evolution of human populatons is from small, isolated groups of individuals, it seems likely that each population would have a different spontaneous mutation rate. Given that a minimum of twenty genes control or affect the spontaneous mutation rate, and that each of these in turn is susceptible to spontaneously arising or environmentally induced mutations, it seems likely that every individual within a population (except for siblings from identical multiple births) will have a unique spontaneous mutation rate. If each individual in a population does have a different spontaneous mutation rate, the doubling dose concept, in rigorous terms, is fallacious. Therefore, as with other concepts of risk evaluation, the doubling dose concept is subject to criticism. Nevertheless, until we know individual spontaneous mutation rates with precision, and can evaluate risks based on this information, the doubling dose concept has a heuristic value and is needed for practical assessment of risks for defined populations. (author)

26 CFR 25.2701-5 - Adjustments to mitigate double taxation.

Science.gov (United States)

2010-04-01

... 26 Internal Revenue 14 2010-04-01 2010-04-01 false Adjustments to mitigate double taxation. 25....2701-5 Adjustments to mitigate double taxation. (a) Reduction of transfer tax base—(1) In general. This... − $187,500). (g) Double taxation otherwise avoided. No reduction is available under this section if— (1...

Pion double charge exchange

International Nuclear Information System (INIS)

Cooper, M.D.

1978-01-01

The pion double charge exchange data on the oxygen isotopes is reviewed and new data on 9 Be, 12 C, 24 Mg, and 28 Si are presented. Where theoretical calculations exist, they are compared to the data. 9 references

Synthesis of Cu-CNTs nanocomposites via double pressing double sintering method

Directory of Open Access Journals (Sweden)

Marjan Darabi

2018-01-01

Full Text Available In this research, copper (Cu-carbon nanotubes (CNTs nanocomposites were synthesized with different weight percentages of CNTs by double pressing double sintering (DPDS method as well as conventional sintering method. A planetary ball mill was used to disperse CNTs in Cu matrix. The milled powders were first cold pressed to 450 MPa in a uniaxial stainless-steel die with cylindrical compacts (diameter: 12 mm and height: 5 mm. The effect of CNTs content and the DPDS method on the properties of the nanocomposites were investigated. The microstructure and phase analysis of Cu-CNTs nanocomposite samples were studied by FESEM and X-Ray Diffraction. The electrical conductivity of nanocomposites was measured and compared to both sintering methods. Mechanical properties of Cu-CNTs nanocomposites were characterized using bending strength and micro-hardness measurements. Enhancements of about 32% in bending strength, 31.6% in hardness and 19.5% in electrical conductivity of Cu-1 wt.% CNTs nanocomposite synthesized by DPDS method were observed as compared to Cu-1 wt.% CNTs nanocomposites fabricated under the similar condition by a conventional sintering process.

False Position, Double False Position and Cramer's Rule

Science.gov (United States)

Boman, Eugene

2009-01-01

We state and prove the methods of False Position (Regula Falsa) and Double False Position (Regula Duorum Falsorum). The history of both is traced from ancient Egypt and China through the work of Fibonacci, ending with a connection between Double False Position and Cramer's Rule.

Double Dynamic Supramolecular Polymers of Covalent Oligo-Dynamers

NARCIS (Netherlands)

Schaeffer, Gaël; Buhler, Eric; Candau, Sauveur Jean; Lehn, Jean-Marie

2013-01-01

Double-dynamic polymers, incorporating both molecular and supramolecular dynamic features (“double dynamers”) have been generated, where these functions are present in a nonstoichiometric ratio in the main chain of the polymer. It has been achieved by (1) the formation of covalent oligo-dynamers in

Performance of an X-ray spectroscopic system based on a double-gate double-feedback charge preamplifier

CERN Document Server

Fazzi, A

2000-01-01

The performance of a near room temperature X-ray spectroscopic system is reported. The system is based on a charge preamplifier with the first transistor having two separated gates. The preamplifier operates in a continuous reset mode without any physical resistor connected to the input node. The leakage current and the current due to the rate of X-rays is neutralized by an average current of holes, flowing under the control of an additional feedback, from the bottom to the top gate. The preamplifier is followed by a simple circuit which exactly cancels the long tail of the impulse response of a pure double-gate preamplifier. The compensation of this tail, due to the very principle of the preamplifier's continuous reset through the double-gate mechanism, improves substantially the high-rate performance of the system. The preamplifier based on a commercially available double-gate front JFET MX-40 (MOXTEK) coupled to a silicon drift detector produced at BNL achieved ENC of 13 electrons at -30 deg. C. The analys...

Free double layers in mercury-arc discharges

International Nuclear Information System (INIS)

Maciel, H.S.; Allen, J.E.

1989-01-01

A study has been carried out of free double layers formed within the plasma volume of a low-pressure mercury-arc discharge at high current densities. The free double layer is observed to form as a visible boundary, which drifts slowly from the central section of the discharge. Current-driven instabilities are observed as the discharge current is gradually increased to a critical value, at which current limitation is observed to occur. This process, which is accompanied by high-current spikes, ceases when the free double layer becomes visible as a sharp boundary dividing the discharge column into two regions of different luminosities. The layer is observed to form in the later stages of current limitation, the onset of which occurs for a ratio of drift to thermal speed of electrons of about unity. Electrical energy is converted by the layer into kinetic energy of the changed particles. Accordingly high-energy ions were measured by means of an electrostatic energy analyser. The multiple-sheath character of the free 'double layer'', which is inferred from probe measurements of potential profiles, is discussed and comparisons with other space-charge structures with the same topology are made. (author)

Dramatic improvement in genome assembly achieved using doubled-haploid genomes.

Science.gov (United States)

Zhang, Hong; Tan, Engkong; Suzuki, Yutaka; Hirose, Yusuke; Kinoshita, Shigeharu; Okano, Hideyuki; Kudoh, Jun; Shimizu, Atsushi; Saito, Kazuyoshi; Watabe, Shugo; Asakawa, Shuichi

2014-10-27

Improvement in de novo assembly of large genomes is still to be desired. Here, we improved draft genome sequence quality by employing doubled-haploid individuals. We sequenced wildtype and doubled-haploid Takifugu rubripes genomes, under the same conditions, using the Illumina platform and assembled contigs with SOAPdenovo2. We observed 5.4-fold and 2.6-fold improvement in the sizes of the N50 contig and scaffold of doubled-haploid individuals, respectively, compared to the wildtype, indicating that the use of a doubled-haploid genome aids in accurate genome analysis.

The history of double tax conventions in Croatia

Directory of Open Access Journals (Sweden)

Hrvoje Arbutina

2014-06-01

Full Text Available After a short introduction, the authors briefly describe the national experience in handling the problems of international double taxation through double tax conventions. This chapter is divided according to stages in the history of double tax conventions identified. The authors analyse the goals of tax treaty policies in differentiated stages with a survey of the economic implications. Special focus is placed on inter-country influences and the impact on and of international institutions and organisations through an examination of the influence of bilateral tax treaties on model tax conventions and vice versa. The fifth chapter presents concluding observations.

Lattice design for the CEPC double ring scheme

Science.gov (United States)

Wang, Yiwei; Su, Feng; Bai, Sha; Zhang, Yuan; Bian, Tianjian; Wang, Dou; Yu, Chenghui; Gao, Jie

2018-01-01

A future Circular Electron Positron Collider (CEPC) has been proposed by China with the main goal of studying the Higgs boson. Its baseline design, chosen on the basis of its performance, is a double ring scheme; an alternative design is a partial double ring scheme which reduces the budget while maintaining an adequate performance. This paper will present the collider ring lattice design for the double ring scheme. The CEPC will also work as a W and a Z factory. For the W and Z modes, except in the RF region, compatible lattices were obtained by scaling down the magnet strength with energy.

AlGaN/GaN double-channel HEMT

International Nuclear Information System (INIS)

Quan Si; Hao Yue; Ma Xiaohua; Zheng Pengtian; Xie Yuanbin

2010-01-01

The fabrication of AlGaN/GaN double-channel high electron mobility transistors on sapphire substrates is reported. Two carrier channels are formed in an AlGaN/GaN/AlGaN/GaN multilayer structure. The DC performance of the resulting double-channel HEMT shows a wider high transconductance region compared with single-channel HEMT. Simulations provide an explanation for the influence of the double-channel on the high transconductance region. The buffer trap is suggested to be related to the wide region of high transconductance. The RF characteristics are also studied. (semiconductor devices)

Why search for double beta decay?

International Nuclear Information System (INIS)

Kayser, B.

1988-01-01

Searching for neutrinoless double beta decay is the only known practical method for trying to determine whether neutrinos are their own antiparticles. The theoretical motivation for supposing that they may indeed be their own antiparticles is described. The reason that it is so difficult to ascertain experimentally whether they are or are not is explained, as is the special sensitivity of neutrinoless double beta decay. The potential implications of the observation of this reaction for neutrino mass and for the physics of neutrinos is discussed

Fermionic formula for double Kostka polynomials

OpenAIRE

Liu, Shiyuan

2016-01-01

The $X=M$ conjecture asserts that the $1D$ sum and the fermionic formula coincide up to some constant power. In the case of type $A,$ both the $1D$ sum and the fermionic formula are closely related to Kostka polynomials. Double Kostka polynomials $K_{\\Bla,\\Bmu}(t),$ indexed by two double partitions $\\Bla,\\Bmu,$ are polynomials in $t$ introduced as a generalization of Kostka polynomials. In the present paper, we consider $K_{\\Bla,\\Bmu}(t)$ in the special case where $\\Bmu=(-,\\mu'').$ We formula...

Search for Neutrinoless Double-Beta Decay

OpenAIRE

Tornow, Werner

2014-01-01

After the pioneering work of the Heidelberg-Moscow (HDM) and International Germanium Experiment (IGEX) groups, the second round of neutrinoless double-$\\beta$ decay searches currently underway has or will improve the life-time limits of double-$\\beta$ decay candidates by a factor of two to three, reaching in the near future the $T_{1/2} = 3 \\times 10^{25}$ yr level. This talk will focus on the large-scale experiments GERDA, EXO-200, and KamLAND-Zen, which have reported already lower half-life...

Moral absolutism and the double-effect exception: reflections on Joseph Boyle's Who is entitled to double effect?

Science.gov (United States)

Donagan, A

1991-10-01

Joseph Boyle raises important questions about the place of the double-effect exception in absolutist moral theories. His own absolutist theory (held by many, but not all, Catholic moralists), which derives from the principles that fundamental human goods may not be intentionally violated, cannot dispense with such exceptions, although he rightly rejects some widely held views about what they are. By contrast, Kantian absolutist theory, which derives from the principle that lawful freedom must not be violated, has a corollary--that it is a duty, where possible, to coerce those who try to violate lawful freedom--which makes superfluous many of the double-effect exceptions Boyle allows. Other implications of the two theories are contrasted. Inter alia, it is argued that, in Boyle's theory, that a violation of a fundamental human good can be viewed as a cost proportionate to a benefit obtained, cannot yield a double-effect exception to the prohibition of intentionally violating that good, because paying a cost cannot be unintentional.

The double layers in the plasma sheet boundary layer during magnetic reconnection

Science.gov (United States)

Guo, J.; Yu, B.

2014-11-01

We studied the evolutions of double layers which appear after the magnetic reconnection through two-dimensional electromagnetic particle-in-cell simulation. The simulation results show that the double layers are formed in the plasma sheet boundary layer after magnetic reconnection. At first, the double layers which have unipolar structures are formed. And then the double layers turn into bipolar structures, which will couple with another new weak bipolar structure. Thus a new double layer or tripolar structure comes into being. The double layers found in our work are about several ten Debye lengths, which accords with the observation results. It is suggested that the electron beam formed during the magnetic reconnection is responsible for the production of the double layers.

Radiative corrections to double-Dalitz decays revisited

Science.gov (United States)

Kampf, Karol; Novotný, Jiři; Sanchez-Puertas, Pablo

2018-03-01

In this study, we revisit and complete the full next-to-leading order corrections to pseudoscalar double-Dalitz decays within the soft-photon approximation. Comparing to the previous study, we find small differences, which are nevertheless relevant for extracting information about the pseudoscalar transition form factors. Concerning the latter, these processes could offer the opportunity to test them—for the first time—in their double-virtual regime.

The R-operator for a modular double

International Nuclear Information System (INIS)

Chicherin, D; Derkachov, S

2014-01-01

We construct the R-operator—the solution of the Yang–Baxter equation acting in the tensor product π s 1 ⊗π s 2 of two infinite-dimensional representations of Faddeev’s modular double. This R-operator intertwines the product of two L-operators associated with the modular double and it is built from three basic operators generating the permutation group of four parameters S 4 . (paper)

On statistical acceleration convergence of double sequences

Directory of Open Access Journals (Sweden)

Bipan Hazarika

2017-04-01

Full Text Available In this article the notion of statistical acceleration convergence of double sequences in Pringsheim's sense has been introduced. We prove the decompostion theorems for  statistical acceleration convergence of double sequences and some theorems related to that concept have been established using the four dimensional matrix transformations. We provided some examples, where the results of acceleration convergence fails to hold for the statistical cases.

Doubled haploid production in Flax (Linum usitatissimum L.).

Science.gov (United States)

Obert, Bohus; Zácková, Zuzana; Samaj, Jozef; Pretová, Anna

2009-01-01

There is a requirement of haploid and double haploid material and homozygous lines for cell culture studies and breeding in flax. Anther culture is currently the most successful method producing doubled haploid lines in flax. Recently, ovary culture was also described as a good source of doubled haploids. In this review we focus on tissue and plants regeneration using anther culture, and cultivation of ovaries containing unfertilized ovules. The effect of genotype, physiological status of donor plants, donor material pre-treatment and cultivation conditions for flax anthers and ovaries is discussed here. The process of plant regeneration from anther and ovary derived calli is also in the focus of this review. Attention is paid to the ploidy level of regenerated tissue and to the use of molecular markers for determining of gametic origin of flax plants derived from anther and ovary cultures. Finally, some future prospects on the use of doubled haploids in flax biotechnology are outlined here.

Double scaling limits and twisted non-critical superstrings

International Nuclear Information System (INIS)

Bertoldi, Gaetano

2006-01-01

We consider double-scaling limits of multicut solutions of certain one matrix models that are related to Calabi-Yau singularities of type A and the respective topological B model via the Dijkgraaf-Vafa correspondence. These double-scaling limits naturally lead to a bosonic string with c ≤ 1. We argue that this non-critical string is given by the topologically twisted non-critical superstring background which provides the dual description of the double-scaled little string theory at the Calabi-Yau singularity. The algorithms developed recently to solve a generic multicut matrix model by means of the loop equations allow to show that the scaling of the higher genus terms in the matrix model free energy matches the expected behaviour in the topological B-model. This result applies to a generic matrix model singularity and the relative double-scaling limit. We use these techniques to explicitly evaluate the free energy at genus one and genus two

Capacitance of carbon-based electrical double-layer capacitors.

Science.gov (United States)

Ji, Hengxing; Zhao, Xin; Qiao, Zhenhua; Jung, Jeil; Zhu, Yanwu; Lu, Yalin; Zhang, Li Li; MacDonald, Allan H; Ruoff, Rodney S

2014-01-01

Experimental electrical double-layer capacitances of porous carbon electrodes fall below ideal values, thus limiting the practical energy densities of carbon-based electrical double-layer capacitors. Here we investigate the origin of this behaviour by measuring the electrical double-layer capacitance in one to five-layer graphene. We find that the capacitances are suppressed near neutrality, and are anomalously enhanced for thicknesses below a few layers. We attribute the first effect to quantum capacitance effects near the point of zero charge, and the second to correlations between electrons in the graphene sheet and ions in the electrolyte. The large capacitance values imply gravimetric energy storage densities in the single-layer graphene limit that are comparable to those of batteries. We anticipate that these results shed light on developing new theoretical models in understanding the electrical double-layer capacitance of carbon electrodes, and on opening up new strategies for improving the energy density of carbon-based capacitors.

Scattering on plane waves and the double copy

Science.gov (United States)

Adamo, Tim; Casali, Eduardo; Mason, Lionel; Nekovar, Stefan

2018-01-01

Perturbatively around flat space, the scattering amplitudes of gravity are related to those of Yang–Mills by colour-kinematic duality, under which gravitational amplitudes are obtained as the ‘double copy’ of the corresponding gauge theory amplitudes. We consider the question of how to extend this relationship to curved scattering backgrounds, focusing on certain ‘sandwich’ plane waves. We calculate the 3-point amplitudes on these backgrounds and find that a notion of double copy remains in the presence of background curvature: graviton amplitudes on a gravitational plane wave are the double copy of gluon amplitudes on a gauge field plane wave. This is non-trivial in that it requires a non-local replacement rule for the background fields and the momenta and polarization vectors of the fields scattering on the backgrounds. It must also account for new ‘tail’ terms arising from scattering off the background. These encode a memory effect in the scattering amplitudes, which naturally double copies as well.

Double-layer appearance after evacuation of a chronic subdural hematoma.

Science.gov (United States)

Sucu, Hasan Kamil; Akar, Ömer

2014-01-01

To investigate the reason for and the course of the double-layer appearance in the postoperative computed tomographies (CTs) of chronic subdural hematoma (CSDHs). We reviewed CSDH cases that were operated on during the last 3 years, between January 2008 and December 2010. We checked the preoperative, early postoperative, and late postoperative CTs of these patients. We investigated the relationship between the formation of a double-layer appearance and the prognoses and demographic characteristics of the patients. Our database included 119 cases. A double-layer appearance was found in the postoperative CTs of 34 cases. The mean age of double-layer cases was older (72.5 ± 12.1) than that of the remaining 85 cases (63.1 ± 17.8). We did not find any relationship between the double-layer appearance and the reoperation/recurrence/death rates. The double-layer appearance after evacuation of a CSDH might be caused by enlargement of the subarachnoid space and is not related to the presence of any residual hematoma. This appearance is not considered as a reason for reoperation.

Conductance of graphene-based double-barrier nanostructures

Energy Technology Data Exchange (ETDEWEB)

Setare, M R [Department of Campus of Bijar, University of Kurdistan, Bijar (Iran, Islamic Republic of); Jahani, D, E-mail: Rezakord@ipm.co, E-mail: Dariush110@gmail.co [Department of Physics, Razi University, Kermanshah (Iran, Islamic Republic of)

2010-12-22

The effect of a mass gap on the conductance of graphene double-barrier heterojunctions is studied. By obtaining the 2D expression for the electronic transport of the low energy excitations of pure graphene through double-barrier systems, it is found that the conductivity of these structures does not depend on the type of charge carriers in the zones of the electric field. However, a finite induced gap in the graphene spectrum makes conductivity dependent on the energy band index. We also discuss a few controversies concerning double-barrier systems stemming from an improper choice of the scattering angle. Then it is observed that, for some special values of the incident energy and potential's height, graphene junctions behave like left-handed materials, resulting in a maximum value for the conductivity.

Conductance of graphene-based double-barrier nanostructures

International Nuclear Information System (INIS)

Setare, M R; Jahani, D

2010-01-01

The effect of a mass gap on the conductance of graphene double-barrier heterojunctions is studied. By obtaining the 2D expression for the electronic transport of the low energy excitations of pure graphene through double-barrier systems, it is found that the conductivity of these structures does not depend on the type of charge carriers in the zones of the electric field. However, a finite induced gap in the graphene spectrum makes conductivity dependent on the energy band index. We also discuss a few controversies concerning double-barrier systems stemming from an improper choice of the scattering angle. Then it is observed that, for some special values of the incident energy and potential's height, graphene junctions behave like left-handed materials, resulting in a maximum value for the conductivity.

Conductance of graphene-based double-barrier nanostructures.

Science.gov (United States)

Setare, M R; Jahani, D

2010-12-22

The effect of a mass gap on the conductance of graphene double-barrier heterojunctions is studied. By obtaining the 2D expression for the electronic transport of the low energy excitations of pure graphene through double-barrier systems, it is found that the conductivity of these structures does not depend on the type of charge carriers in the zones of the electric field. However, a finite induced gap in the graphene spectrum makes conductivity dependent on the energy band index. We also discuss a few controversies concerning double-barrier systems stemming from an improper choice of the scattering angle. Then it is observed that, for some special values of the incident energy and potential's height, graphene junctions behave like left-handed materials, resulting in a maximum value for the conductivity.

Doubled-ended ceramic thyratron

CERN Multimedia

1974-01-01

The double-ended ceramic thyratron CX 1171 B, with its coaxial voltage divider for the SPS. Such a switch, paralleled by three ignitrons in series forms the "thyragnitron" arrangement, and can switch 10 kA, 25 ms pulses, with very fast rise times.

SUSY formalism for the symmetric double well potential

Indian Academy of Sciences (India)

symmetric double well potential barrier we have obtained a class of exactly solvable potentials subject to moving boundary condition. The eigenstates are also obtained by the same technique. Keywords. SUSY; moving boundary condition; exactly solvable; symmetric double well; NH3 molecule. PACS Nos 02.30.Ik; 03.50.

Relativistic pn-QRPA to the double beta decay

International Nuclear Information System (INIS)

Conti, Claudio de; Krmpotic, Francisco; Carlson, Brett Vern

2011-01-01

Full text: In nature there are about 50 nuclear systems where the single beta-decay is energetically forbidden, and double-beta decay turns out to be only possible mode of disintegration. It is the nuclear pairing force which causes such an 'anomaly', by making the mass of the odd-odd isobar, (N - 1;Z + 1), to be greater than the masses of its even-even neighbors, (N;Z) and (N - 2;Z +2). The modes by which the double-beta decay can take place are connected with the neutrino and antineutrino distinction. In case the lepton number is strictly conserved the neutrino is a Dirac fermion and the two-neutrino mode is the only possible mode of disintegration. On the other hand, if this conservation is violated, the neutrino is a Majorana particle and neutrinoless double-beta decay also can occur. Both two-neutrino and neutrinoless double-beta decay processes have attracted much attention, because a comparison between experiment and theory for the first, provides a measure of confidence one may have in the nuclear wave function employed for extracting the unknown parameters from neutrinoless lifetime measurements. The proton-neutron (pn) quasiparticle random phase approximation (QRPA) has turned out be the most simple model for calculating the nuclear wave function involved in the double-beta decay transitions. In this work the transition matrix elements for 0 + → 0 + double-beta decay are calculated for 48 Ca, 76 Ge, 82 Se, 100 Mo, 128 Te and 130 Te nuclei, using a relativistic pn-QRPA based on Hartree-Bogoliubov approximation to the single-particle motion. (author)

Adsorption of procion red using layer double hydroxide Mg/Al

Directory of Open Access Journals (Sweden)

Muhammad Imron

2017-07-01

Full Text Available Layer double hydroxide Mg/Al was synthesized by inorganic synthetic method. Material was characterized using FTIR and XRD analyses and used as adsorbent of procion red dye in aqueous medium.  Factors that affect the adsorption process are adsorption time as the kinetic parameter; and the temperature and concentration of procion red as the thermodynamic parameter. FTIR spectra of layer double hydroxides showed unique vibration at wavenumber 1300 cm-1 and 1600 cm-1. Characterization using XRD shows diffraction angles at 29o, 27o, and 28o, which are typical of Mg/Al double layer hydroxides. Adsorption of procion red using layer double hydroxide Mg/Al resulted adsorption rate 7.1 minutes-1, maximum adsorption capacity 111.1 mg/g at 60 oC with increasing energy by increasing adsorption temperature.   Keywords: Layered double hydroxides, adsorption, procion red.

On Rational Design of Double Hull Tanker Structures against Collision

DEFF Research Database (Denmark)

Paik, Jeom Kee; Chung, Jang Young; Choe, Ich Hung

1999-01-01

This paper is a summary of recent research and development in areas related to the design technology for double hull tanker structures against low energy collision, jointly undertaken by the Hyundai Heavy Industries, the American Bureau of Shipping, the Technical University of Denmark and the Pusan...... in the present study were (i) developing a framework for the collision design procedure for double hull tanker structures, (ii) experimental investigation of the structural crashworthiness of the collided vessels in collision or stranding, using double skinned structural models, (iii) validation of the special...... investigation of the energy absorption capability characteristics of a collided double hull VLCC side structure in collision, and (vi) development of a new modified Minorsky method for double hull tanker side structures. The tools developed and the results and insights obtained by the present study should...

The Double Star mission

Directory of Open Access Journals (Sweden)

Liu

2005-11-01

Full Text Available The Double Star Programme (DSP was first proposed by China in March, 1997 at the Fragrant Hill Workshop on Space Science, Beijing, organized by the Chinese Academy of Science. It is the first mission in collaboration between China and ESA. The mission is made of two spacecraft to investigate the magnetospheric global processes and their response to the interplanetary disturbances in conjunction with the Cluster mission. The first spacecraft, TC-1 (Tan Ce means "Explorer", was launched on 29 December 2003, and the second one, TC-2, on 25 July 2004 on board two Chinese Long March 2C rockets. TC-1 was injected in an equatorial orbit of 570x79000 km altitude with a 28° inclination and TC-2 in a polar orbit of 560x38000 km altitude. The orbits have been designed to complement the Cluster mission by maximizing the time when both Cluster and Double Star are in the same scientific regions. The two missions allow simultaneous observations of the Earth magnetosphere from six points in space. To facilitate the comparison of data, half of the Double Star payload is made of spare or duplicates of the Cluster instruments; the other half is made of Chinese instruments. The science operations are coordinated by the Chinese DSP Scientific Operations Centre (DSOC in Beijing and the European Payload Operations Service (EPOS at RAL, UK. The spacecraft and ground segment operations are performed by the DSP Operations and Management Centre (DOMC and DSOC in China, using three ground station, in Beijing, Shanghai and Villafranca.

Generating multi-double-scroll attractors via nonautonomous approach.

Science.gov (United States)

Hong, Qinghui; Xie, Qingguo; Shen, Yi; Wang, Xiaoping

2016-08-01

It is a common phenomenon that multi-scroll attractors are realized by introducing the various nonlinear functions with multiple breakpoints in double scroll chaotic systems. Differently, we present a nonautonomous approach for generating multi-double-scroll attractors (MDSA) without changing the original nonlinear functions. By using the multi-level-logic pulse excitation technique in double scroll chaotic systems, MDSA can be generated. A Chua's circuit, a Jerk circuit, and a modified Lorenz system are given as designed example and the Matlab simulation results are presented. Furthermore, the corresponding realization circuits are designed. The Pspice results are in agreement with numerical simulation results, which verify the availability and feasibility of this method.

Electron-impact single and double ionization of W

International Nuclear Information System (INIS)

Pindzola, M S; Loch, S D; Foster, A R

2017-01-01

Electron-impact single and double ionization cross sections for the W atom are calculated using a semi-relativistic distorted-wave method. The cross sections include contributions from single direct ionization, double direct ionization and excitation-autoionization. Branching ratio calculations are made to determine whether an excitation may contribute to single or double ionization. We check the accuracy of the semi-relativistic distorted-wave calculations for direct ionization of various subshells by comparison with fully-relativistic distorted-wave calculations. We also check the accuracy of the perturbative distorted-wave calculations for direct ionization of the outer most subshells by comparison with non-perturbative time-dependent close-coupling calculations. (paper)

Choosing Double: The Relationship between Successful AP® Exams and College Double Major

Science.gov (United States)

Ewing, Maureen; Jagesic, Sanja; Wyatt, Jeff

2018-01-01

Students who double major have higher earnings and are more satisfied with their educational experience in college than those who graduate with a single major. In this study, the authors examine the extent to which a student's experience with academic acceleration programs in high school, specifically successful participation in the Advanced…

Invariant and Absolute Invariant Means of Double Sequences

Directory of Open Access Journals (Sweden)

Abdullah Alotaibi

2012-01-01

Full Text Available We examine some properties of the invariant mean, define the concepts of strong σ-convergence and absolute σ-convergence for double sequences, and determine the associated sublinear functionals. We also define the absolute invariant mean through which the space of absolutely σ-convergent double sequences is characterized.

Dealing with double trouble: consequences of single and double herbivory in Brassica juncea

NARCIS (Netherlands)

Mathur, V.; Tytgat, T.O.G.; Graaf, de R.M.; Kalia, V.; Reddy, A.S.; Vet, L.E.M.; Dam, van N.M.

2013-01-01

In their natural environment, plants are often attacked simultaneously by many insect species. The specificity of induced plant responses that is reported after single herbivore attacks may be compromised under double herbivory and this may influence later arriving herbivores. The present study

Double-Capon and double-MUSICAL for arrival separation and observable estimation in an acoustic waveguide

Science.gov (United States)

Touzé, Grégoire Le; Nicolas, Barbara; Mars, Jérôme I.; Roux, Philippe; Oudompheng, Benoit

2012-12-01

Recent developments in shallow water ocean acoustic tomography propose the use of an original configuration composed of two source-receiver vertical arrays and wideband sources. The recording space thus has three dimensions, with two spatial dimensions and the frequency dimension. Using this recording space, it is possible to build a three-dimensional (3D) estimation space that gives access to the three observables associated with the acoustic arrivals: the direction of departure, the direction of arrivals, and the time of arrival. The main interest of this 3D estimation space is its capability for the separation of acoustic arrivals that usually interfere in the recording space, due to multipath propagation. A 3D estimator called double beamforming has already been developed, although it has limited resolution. In this study, the new 3D high-resolution estimators of double Capon and double MUSICAL are proposed to achieve this task. The ocean acoustic tomography configuration allows a single recording realization to estimate the cross-spectral data matrix, which is necessary to build high-resolution estimators. 3D smoothing techniques are thus proposed to increase the rank of the matrix. The estimators developed are validated on real data recorded in an ultrasonic tank, and their detection performances are compared to existing 2D and 3D methods.

Formation of double galaxies by tidal capture

International Nuclear Information System (INIS)

Alladin, S.M.; Potdar, A.; Sastry, K.S.

1975-01-01

The conditions under which double galaxies may be formed by tidal capture are considered. Estimates for the increase in the internal energy of colliding galaxies due to tidal effects are used to determine the magnitudes Vsub(cap) and Vsub(dis) of the maximum relative velocities at infinite separation required for tidal capture and tidal disruption respectively. A double galaxy will be formed by tidal capture without tidal disruption of a component if Vsub(cap)>Vsub(i) and Vsub(cap)>Vsub(dis) where Vsub(i) is the initial relative speed of the two galaxies at infinite separation. If the two galaxies are of the same dimension, formulation of double galaxies by tidal capture is possible in a close collision either if the two galaxies do not differ much in mass and density distribution or if the more massive galaxy is less centrally concentrated than the other. If it is assumed as statistics suggest, that the mass of a galaxy is proportional to the square of its radius, it follows that the probability of the formation of double galaxies by tidal capture increases with the increase in mass of the galaxies and tidal distribution does not occur in a single collision for any distance of closest approach of the two galaxies. (Auth.)

Double transparent conducting layers for Si photovoltaics

Energy Technology Data Exchange (ETDEWEB)

Yun, Ju-Hyung [Department of Electrical Engineering, University at Buffalo, State University of New York, Buffalo, NY 14260 (United States); Kim, Joondong, E-mail: joonkim@incheon.ac.kr [Department of Electrical Engineering, Incheon National University, Incheon, 406772 (Korea, Republic of); Park, Yun Chang [Measurement and Analysis Division, National Nanofab Center (NNFC), Daejeon 305806 (Korea, Republic of); Moon, Sang-Jin [Energy Materials Research Center, Korea Research Institute of Chemical Technology (KRICT), Daejeon 305-600 (Korea, Republic of); Anderson, Wayne A. [Department of Electrical Engineering, University at Buffalo, State University of New York, Buffalo, NY 14260 (United States)

2013-11-29

Double transparent conductive oxide (TCO) film-embedded Si heterojunction solar cells were fabricated. An intentional doping was not applied for heterojunction solar cells due to the spontaneous Schottky junction formation between TCO films and an n-type Si substrate. Three different TCO coatings were formed by sputtering method for an Al-doped ZnO (AZO) film, an indium-tin-oxide (ITO) film and double stacks of ITO/AZO films. An improved crystalline ITO film was grown on an AZO template upon hetero-epitaxial growth. This double TCO films-embedded Si (ITO/AZO/Si) heterojunction solar cell provided significantly enhanced efficiency of 9.23 % as compared to the single TCO/Si (ITO/Si or AZO/Si) devices due to the optical and the electrical benefits. The effective arrangement of TCO films (ITO/AZO) provides benefits of a lower front contact resistance and a smaller band offset to Si leading enhanced photovoltaic performances. This demonstrates a potential scheme for an effective TCO film-embedded heterojunction Si solar cell. - Highlights: • Double transparent conducting oxide films form a heterojunction to Si. • A quality indium-tin-oxide film was grown above an Al-doped zinc oxide template. • Heterojunction Si solar cell was made without an intentional doping process.

Double transparent conducting layers for Si photovoltaics

International Nuclear Information System (INIS)

Yun, Ju-Hyung; Kim, Joondong; Park, Yun Chang; Moon, Sang-Jin; Anderson, Wayne A.

2013-01-01

Double transparent conductive oxide (TCO) film-embedded Si heterojunction solar cells were fabricated. An intentional doping was not applied for heterojunction solar cells due to the spontaneous Schottky junction formation between TCO films and an n-type Si substrate. Three different TCO coatings were formed by sputtering method for an Al-doped ZnO (AZO) film, an indium-tin-oxide (ITO) film and double stacks of ITO/AZO films. An improved crystalline ITO film was grown on an AZO template upon hetero-epitaxial growth. This double TCO films-embedded Si (ITO/AZO/Si) heterojunction solar cell provided significantly enhanced efficiency of 9.23 % as compared to the single TCO/Si (ITO/Si or AZO/Si) devices due to the optical and the electrical benefits. The effective arrangement of TCO films (ITO/AZO) provides benefits of a lower front contact resistance and a smaller band offset to Si leading enhanced photovoltaic performances. This demonstrates a potential scheme for an effective TCO film-embedded heterojunction Si solar cell. - Highlights: • Double transparent conducting oxide films form a heterojunction to Si. • A quality indium-tin-oxide film was grown above an Al-doped zinc oxide template. • Heterojunction Si solar cell was made without an intentional doping process

Double shell planar experiments on OMEGA

Science.gov (United States)

Dodd, E. S.; Merritt, E. C.; Palaniyappan, S.; Montgomery, D. S.; Daughton, W. S.; Schmidt, D. W.; Cardenas, T.; Wilson, D. C.; Loomis, E. N.; Batha, S. H.; Ping, Y.; Smalyuk, V. A.; Amendt, P. A.

2017-10-01

The double shell project is aimed at fielding neutron-producing capsules at the National Ignition Facility (NIF), in which an outer low-Z ablator collides with an inner high-Z shell to compress the fuel. However, understanding these targets experimentally can be challenging when compared with conventional single shell targets. Halfraum-driven planar targets at OMEGA are being used to study physics issues important to double shell implosions outside of a convergent geometry. Both VISAR and radiography through a tube have advantages over imaging through the hohlraum and double-shell capsule at NIF. A number physics issues are being studied with this platform that include 1-d and higher dimensional effects such as defect-driven hydrodynamic instabilities from engineering features. Additionally, the use of novel materials with controlled density gradients require study in easily diagnosed 1-d systems. This work ultimately feeds back into the NIF capsule platform through manufacturing tolerances set using data from OMEGA. Supported under the US DOE by the LANS, LLC under contract DE-AC52-06NA25396. LA-UR-17-25386.

Double Fano resonances in plasmon coupling nanorods

International Nuclear Information System (INIS)

Liu, Fei; Jin, Jie

2015-01-01

Fano resonances are investigated in nanorods with symmetric lengths and side-by-side assembly. Single Fano resonance can be obtained by a nanorod dimer, and double Fano resonances are shown in nanorod trimers with side-by-side assembly. With transverse plasmon excitation, Fano resonances are caused by the destructive interference between a bright superradiant mode and dark subradiant modes. The bright mode originates from the electric plasmon resonance, and the dark modes originate from the magnetic resonances induced by near-field inter-rod coupling. Double Fano resonances result from double dark modes at different wavelengths, which are induced and tuned by the asymmetric gaps between the adjacent nanorods. Fano resonances show a high figure of merit and large light extinction in the periodic array of assembled nanorods, which can potentially be used in multiwavelength sensing in the visible and near-infrared regions. (paper)

Radiation Protection, double-blind studies with radiopharmaceuticals

International Nuclear Information System (INIS)

Pujadas, M. C.; Camacho, C.; Guasp, M.; Villaescusa, J. I.

2009-01-01

In a double-blind randomized controlled clinical trial (RCT) subjects and researchers do not know the assignment to treatment groups to ovoid the appearance of subjective biases of information. The employment of radiopharmaceuticals in double-blind RCTs raises a dilemma from the point ov view of the radiological protection. On the one hand, the obligation to act in cases of contamination and/or risk of irradiation exists, but on the other hand the duty of keeping the blind study also exists. In this paper some of the possible problems that arise when conducting a double-blind RCT with radiopharmaceuticals from the point of view of the radiological protection are presented. We comment our experience with the radiopharmaceutical Alpharadin and, in addition, we propose useful recommendations based on the randomness of the decontamination process. (Author) 7 refs.

Impact on Sensex of Scrapping Double Taxation of Dividends

OpenAIRE

Ragunathan V; Varma, Jayanth R.

1997-01-01

The taxation of dividends has generated an active debate in recent months in the media. While the industry representatives have been critical of the double taxation of dividends, the Government seems to be questioning the very premise that dividends are double taxed in India. The argument that scrapping the double taxation of dividends will give the Sensex a much needed boost seems to have tilted the scales. What will be the impact of scrapping of dividend tax on Sensex? One finds that the st...

More Effective Use of Urban Space by Autonomous Double Parking

Directory of Open Access Journals (Sweden)

Rafael Estepa

2017-01-01

Full Text Available The new capabilities of autonomous cars can be used to mitigate to a large extent safety concerns and nuisance traditionally associated with double parking. In this paper double parking for autonomous cars is proposed as a new approach to temporarily increase parking capacity in locations in clear need for extra provision when best alternatives cannot be found. The basic requirements, operation, and procedures of the proposed solution are outlined. A curbside parking has been simulated implementing the suggested double parking operation and important advantages have been identified for drivers, the environment, and the city. Double parking can increase over 50% the parking capacity of a given area. Autonomous car owners would (at least double their probabilities of finding parking compared to traditional drivers, saving cruising time and emissions. However, significant work and technological advances are still needed in order to make this feasible in the near future.

Numerical simulations on ion acoustic double layers

International Nuclear Information System (INIS)

Sato, T.; Okuda, H.

1980-07-01

A comprehensive numerical study of ion acoustic double layers has been performed for both periodic as well as for nonperiodic systems by means of one-dimensional particle simulations. For a nonperiodic system, an external battery and a resistance are used to model the magnetospheric convection potential and the ionospheric Pedersen resistance. It is found that the number of double layers and the associated potential buildup across the system increases with the system length

DNA Damage by Ionizing Radiation: Tandem Double Lesions by Charged Particles

Science.gov (United States)

Huo, Winifred M.; Chaban, Galina M.; Wang, Dunyou; Dateo, Christopher E.

2005-01-01

Oxidative damages by ionizing radiation are the source of radiation-induced carcinogenesis, damage to the central nervous system, lowering of the immune response, as well as other radiation-induced damages to human health. Monte Carlo track simulations and kinetic modeling of radiation damages to the DNA employ available molecular and cellular data to simulate the biological effect of high and low LET radiation io the DNA. While the simulations predict single and double strand breaks and base damages, so far all complex lesions are the result of stochastic coincidence from independent processes. Tandem double lesions have not yet been taken into account. Unlike the standard double lesions that are produced by two separate attacks by charged particles or radicals, tandem double lesions are produced by one single attack. The standard double lesions dominate at the high dosage regime. On the other hand, tandem double lesions do not depend on stochastic coincidences and become important at the low dosage regime of particular interest to NASA. Tandem double lesions by hydroxyl radical attack of guanine in isolated DNA have been reported at a dosage of radiation as low as 10 Gy. The formation of two tandem base lesions was found to be linear with the applied doses, a characteristic of tandem lesions. However, tandem double lesions from attack by a charged particle have not been reported.

Application of the double-contingency principle within BNFL

International Nuclear Information System (INIS)

Strafford, P.I.D.

1995-01-01

Historically, the double-contingency principle has been used for criticality assessment within British Nuclear Fuels plc (BNFL). This paper outlines what is understood by the double-contingency principle to illustrate how it is applied in criticality safety assessments and to highlight various problem areas that are encountered and, where possible, how they might be solved

Trial design and manufacture of double spiral grooved vacuum pump; Double neji mizoshiki shinku pump no shisaku

Energy Technology Data Exchange (ETDEWEB)

Iguchi, M.; Sawada, T.; Sugiyama, W. [Akita University, Akita (Japan). Faculty of Mining; Watanabe, M.

1997-04-25

A spiral grooved vacuum pump and a compound molecular pump (the combination of a spiral grooved pump and a turbomolecular pump) are widely used in the thin-film industry for processes such as semiconductor production. Pumping performance is high at pressures below 1 000 Pa and low at pressures above 1000 Pa when the clearance between rotor and stator is on the order of 0.1 mm, which is the practical value for industrial use. The double spiral grooved vacuum pump is thought to have better pumping performance at such high pressures than the conventional spiral grooved vacuum pump. The aim of this study is to investigate the feasibility of use of the double spiral grooved vacuum pump at pressures above 1000 Pa. A double spiral grooved vacuum pump with a rotor of 150 mm diameter and 190 mm length has been designed and manufactured. Its pumping performance has been tested by experiments. The test results show the improvement in the performance at pressures above 1000 Pa compared to the conventional spiral grooved vacuum pump. 2 refs., 12 figs., 2 tabs.

Micrometer and CCD measurements of double stars (Series 51

Directory of Open Access Journals (Sweden)

Popović G.M.

1998-01-01

Full Text Available 36 micrometric measurements of 20 double or multiple systems carried out with the Zeiss 65/1055 cm Refractor of Belgrade Observatory are communicated. Also 35 CCD measurements of 15 double or multiple systems are included.

Faster Double-Size Bipartite Multiplication out of Montgomery Multipliers

Science.gov (United States)

Yoshino, Masayuki; Okeya, Katsuyuki; Vuillaume, Camille

This paper proposes novel algorithms for computing double-size modular multiplications with few modulus-dependent precomputations. Low-end devices such as smartcards are usually equipped with hardware Montgomery multipliers. However, due to progresses of mathematical attacks, security institutions such as NIST have steadily demanded longer bit-lengths for public-key cryptography, making the multipliers quickly obsolete. In an attempt to extend the lifespan of such multipliers, double-size techniques compute modular multiplications with twice the bit-length of the multipliers. Techniques are known for extending the bit-length of classical Euclidean multipliers, of Montgomery multipliers and the combination thereof, namely bipartite multipliers. However, unlike classical and bipartite multiplications, Montgomery multiplications involve modulus-dependent precomputations, which amount to a large part of an RSA encryption or signature verification. The proposed double-size technique simulates double-size multiplications based on single-size Montgomery multipliers, and yet precomputations are essentially free: in an 2048-bit RSA encryption or signature verification with public exponent e=216+1, the proposal with a 1024-bit Montgomery multiplier is at least 1.5 times faster than previous double-size Montgomery multiplications.

Rare transformation to double hit lymphoma in Waldenstrom's macroglobulinemia.

Science.gov (United States)

Okolo, Onyemaechi N; Johnson, Ariel C; Yun, Seongseok; Arnold, Stacy J; Anwer, Faiz

2017-08-01

Waldenström macroglobulinemia (WM) is a lymphoproliferative lymphoma that is characterized by monoclonal immunoglobulin M (IgM) protein and bone marrow infiltration. Its incidence is rare and rarer still is its ability to transform to a B-cell lymphoma, particularly the aggressive diffuse large B-cell lymphoma, which bodes a poor prognosis. When transformation includes mutations of MYC, BCL-2 and/or BCL-6, it is known as a 'double hit' or 'triple hit' lymphoma respectively. This paper presents a rare case of WM with mutations positive for MYC and BCL2, making it a case of double hit B-cell lymphoplasmacytic lymphoma with plasmatic differentiation without morphological transformation to aggressive histology like DLBCL. The paper also broadens to include discussions on current topics in the classification, diagnosis, possible causes of transformation, and treatment of WM, including transformation to double hit lymphoma. The significance of this case lies in that the presence of double hit lymphoma-like genetic mutations in WM have not been previously described in the literature and potentially such changes are harbinger of extra-nodal presentation, aggressive growth, and possibly poor prognosis, if data from other double-hit lymphoma are extrapolated.

Double-Scope Peroral Endoscopic Myotomy (POEM for Esophageal Achalasia: The First Trial of a New Double-Scope POEM

Directory of Open Access Journals (Sweden)

Hee Jin Hong

2016-07-01

Full Text Available With the accumulation of clinical trials demonstrating its efficacy and safety, peroral endoscopic myotomy (POEM has emerged as a less invasive treatment option for esophageal achalasia compared with laparoscopic Heller myotomy. However, the difficulty in determining the exact extent of myotomy, a critical factor associated with the success and safety of the procedure, remains a limitation. Although the various endoscopic landmarks and ancillary techniques have been applied, none of these has been proven sufficient. As a solution for this limitation, the double-scope POEM technique with a second endoscope to assure the exact length of the submucosal tunnel has been applied since 2014. Before double-scope POEM was introduced, the second endoscope was applied only to confirm the accuracy of the procedure. In the present study, we performed double-scope POEM in the treatment of esophageal achalasia through a novel procedure of simultaneous application of the second endoscope to assist in the conventional POEM procedure.

Simulation Results of Double Forward Converter

Directory of Open Access Journals (Sweden)

P. Vijaya KUMAR

2009-12-01

Full Text Available This work aims to find a better forward converter for DC to DC conversion.Simulation of double forward converter in SMPS system is discussed in this paper. Aforward converter with RCD snubber to synchronous rectifier and/or to current doubleris also discussed. The evolution of the forward converter is first reviewed in a tutorialfashion. Performance parameters are discussed including operating principle, voltageconversion ratio, efficiency, device stress, small-signal dynamics, noise and EMI. Itscircuit operation and its performance characteristics of the forward converter with RCDsnubber and double forward converter are described and the simulation results arepresented.

Generating multi-double-scroll attractors via nonautonomous approach

Energy Technology Data Exchange (ETDEWEB)

Hong, Qinghui; Xie, Qingguo, E-mail: qgxie@mail.hust.edu.cn [Wuhan National Laboratory for Optoelectronics, Wuhan 430074 (China); Shen, Yi; Wang, Xiaoping [School of Automation, Huazhong University of Science and Technology, Wuhan 430074 (China)

2016-08-15

It is a common phenomenon that multi-scroll attractors are realized by introducing the various nonlinear functions with multiple breakpoints in double scroll chaotic systems. Differently, we present a nonautonomous approach for generating multi-double-scroll attractors (MDSA) without changing the original nonlinear functions. By using the multi-level-logic pulse excitation technique in double scroll chaotic systems, MDSA can be generated. A Chua's circuit, a Jerk circuit, and a modified Lorenz system are given as designed example and the Matlab simulation results are presented. Furthermore, the corresponding realization circuits are designed. The Pspice results are in agreement with numerical simulation results, which verify the availability and feasibility of this method.

Young's double-slit interference with two-color biphotons.

Science.gov (United States)

Zhang, De-Jian; Wu, Shuang; Li, Hong-Guo; Wang, Hai-Bo; Xiong, Jun; Wang, Kaige

2017-12-12

In classical optics, Young's double-slit experiment with colored coherent light gives rise to individual interference fringes for each light frequency, referring to single-photon interference. However, two-photon double-slit interference has been widely studied only for wavelength-degenerate biphoton, known as subwavelength quantum lithography. In this work, we report double-slit interference experiments with two-color biphoton. Different from the degenerate case, the experimental results depend on the measurement methods. From a two-axis coincidence measurement pattern we can extract complete interference information about two colors. The conceptual model provides an intuitional picture of the in-phase and out-of-phase photon correlations and a complete quantum understanding about the which-path information of two colored photons.

Equilibrium and Nonequilibrium States in Microfluidic Double Emulsions

DEFF Research Database (Denmark)

Pannacci, N.; Bruus, Henrik; Bartolo, D.

2008-01-01

We describe experimental and theoretical studies dedicated to establishing the physics of formation of double droplets in microfluidic systems. We show that the morphologies (complete engulfing, partial engulfing, and nonengulfing) obtained at late times minimize the interfacial energy of the sys......We describe experimental and theoretical studies dedicated to establishing the physics of formation of double droplets in microfluidic systems. We show that the morphologies (complete engulfing, partial engulfing, and nonengulfing) obtained at late times minimize the interfacial energy...... of the system. We explain that nonequilibrium morphologies generated in the system can have long lifetimes. Remarkably, the physics of formation of the double droplets with microfluidics allows the synthesis of particles with new morphologies....

Symmetry breaking in the double-well hermitian matrix models

CERN Document Server

Brower, R C; Jain, S; Tan, C I; Brower, Richard C.; Deo, Nevidita; Jain, Sanjay; Tan, Chung-I

1993-01-01

We study symmetry breaking in $Z_2$ symmetric large $N$ matrix models. In the planar approximation for both the symmetric double-well $\\phi^4$ model and the symmetric Penner model, we find there is an infinite family of broken symmetry solutions characterized by different sets of recursion coefficients $R_n$ and $S_n$ that all lead to identical free energies and eigenvalue densities. These solutions can be parameterized by an arbitrary angle $\\theta(x)$, for each value of $x = n/N < 1$. In the double scaling limit, this class reduces to a smaller family of solutions with distinct free energies already at the torus level. For the double-well $\\phi^4$ theory the double scaling string equations are parameterized by a conserved angular momentum parameter in the range $0 \\le l < \\infty$ and a single arbitrary $U(1)$ phase angle.

Performance analysis of double basin solar still with evacuated tubes

International Nuclear Information System (INIS)

Hitesh N Panchal; Shah, P. K.

2013-01-01

Solar still is a very simple device, which is used for solar distillation process. In this research work, double basin solar still is made from locally available materials. Double basin solar still is made in such a way that, outer basin is exposed to sun and lower side of inner basin is directly connected with evacuated tubes to increase distillate output and reducing heat losses of a solar still. The overall size of the lower basin is about 1006 mm x 325 mm x 380 mm, the outer basin is about 1006 mm x 536 mm x 100 mm Black granite gravel is used to increase distillate output by reducing quantity of brackish or saline water in the both basins. Several experiments have conducted to determine the performance of a solar still in climate conditions of Mehsana (latitude of 23 degree 59' and longitude of 72 degree 38'), Gujarat, like a double basin solar still alone, double basin solar still with different size black granite gravel, double basin solar still with evacuated tubes and double basin solar still with evacuated tubes and different size black granite gravel. Experimental results show that, connecting evacuated tubes with the lower side of the inner basin increases daily distillate output of 56% and is increased by 60%, 63% and 67% with average 10 mm, 20 mm and 30 mm size black granite gravel. Economic analysis of present double basin solar still is 195 days. (authors)

Polarisation observables F and T in double π{sup 0} photoproduction

Energy Technology Data Exchange (ETDEWEB)

Garni, Stefanie [Departement of Physics, University of Basel, CH-4056 Basel (Switzerland); Collaboration: A2-Collaboration

2013-07-01

The measurement of single and double polarization observables gives information about the different resonance contributions to the cross section and hence leads to a better understanding of the nucleon and it's excited states. Double π{sup 0} photo-production is a very interesting reaction for the investigation of nuclear resonances. Photo-production of pion pairs allows to study states which decay preferentially via intermediate resonances. The double neutral channel has the additional advantage of only small non-resonant background contributions. Double π{sup 0}-photo-production off a transversally polarized H-butanol target has been measured using circularly polarized bremsstrahlung photons produced by MAMI-C with incident energies up to 1.5 GeV. The double π{sup 0} reaction was identified using a combined setup of the Crystal Ball colorimeter and a TAPS forward wall which results in an almost 4π acceptance. Preliminary results on the single polarization observable T and double polarization observable F are presented.

Single-row versus double-row rotator cuff repair: techniques and outcomes.

Science.gov (United States)

Dines, Joshua S; Bedi, Asheesh; ElAttrache, Neal S; Dines, David M

2010-02-01

Double-row rotator cuff repair techniques incorporate a medial and lateral row of suture anchors in the repair configuration. Biomechanical studies of double-row repair have shown increased load to failure, improved contact areas and pressures, and decreased gap formation at the healing enthesis, findings that have provided impetus for clinical studies comparing single-row with double-row repair. Clinical studies, however, have not yet demonstrated a substantial improvement over single-row repair with regard to either the degree of structural healing or functional outcomes. Although double-row repair may provide an improved mechanical environment for the healing enthesis, several confounding variables have complicated attempts to establish a definitive relationship with improved rates of healing. Appropriately powered rigorous level I studies that directly compare single-row with double-row techniques in matched tear patterns are necessary to further address these questions. These studies are needed to justify the potentially increased implant costs and surgical times associated with double-row rotator cuff repair.

Meson exchange currents and two neutrino double beta decay

International Nuclear Information System (INIS)

Simkovic, F.

1995-01-01

By using a field theory approach a detailed analysis of the two neutrino double beta decay amplitude has been performed. We have shown that the summation over the intermediate nuclear states in the present two neutrino double beta decay studies corresponds to a summation over a class of meson exchange diagrams. We offer some arguments showing that the two nucleon mechanism considered at present does not provide the main contribution to the two neutrino double beta decay amplitude. A new electron-gamma exchange mechanism for this process is suggested. 31 refs., 1 fig

DOE requests waiver on double containment for HLW canisters

International Nuclear Information System (INIS)

Lobsenz, G.

1994-01-01

The Energy Department has asked the Nuclear Regulatory Commission to waive double containment requirements for vitrified high-level radioactive waste canisters, saying the additional protection is not necessary and too costly. NRC said it had received a petition from DOE contending that the vitrified waste canisters were durable enough without double containment to prevent any potential plutonium release during handling and shipping. DOE said testing had shown that the vitrified waste canisters were similar - even superior - in durability to spent reactor fuel shipments, which NRC specifically exempted from the double containment requirement

Detection of internal fields in double-metal terahertz resonators

DEFF Research Database (Denmark)

Mitrofanov, Oleg; Han, Zhanghua; Ding, Fei

2017-01-01

Terahertz (THz) double-metal plasmonic resonators enable enhanced light-matter coupling by exploiting strong field confinement. The double-metal design however restricts access to the internal fields. We propose and demonstrate a method for spatial mapping and spectroscopic analysis of the internal...... electromagnetic fields in double-metal plasmonic resonators. We use the concept of image charges and aperture-type scanning near-field THz time-domain microscopy to probe the fields confined within the closed resonator. The experimental method opens doors to studies of light-matter coupling in deeply sub...

The quantum double in integrable quantum field theory

International Nuclear Information System (INIS)

Bernard, D.; LeClair, A.

1993-01-01

Various aspects of recent works on affine quantum group symmetry of integrable 2D quantum field theory are reviewed and further clarified. A geometrical meaning is given to the quantum double, and other properties of quantum groups. The S-matrix is identified with the universal R-matrix. Multiplicative presentations of the yangian double are analyzed. (orig.)

Double quantum dot as a minimal thermoelectric generator

OpenAIRE

Donsa, S.; Andergassen, S.; Held, K.

2014-01-01

Based on numerical renormalization group calculations, we demonstrate that experimentally realized double quantum dots constitute a minimal thermoelectric generator. In the Kondo regime, one quantum dot acts as an n-type and the other one as a p-type thermoelectric device. Properly connected the double quantum dot provides a miniature power supply utilizing the thermal energy of the environment.

Double-Difference Global Adjoint Tomography

Science.gov (United States)

Orsvuran, R.; Bozdag, E.; Lei, W.; Tromp, J.

2017-12-01

The adjoint method allows us to incorporate full waveform simulations in inverse problems. Misfit functions play an important role in extracting the relevant information from seismic waveforms. In this study, our goal is to apply the Double-Difference (DD) methodology proposed by Yuan et al. (2016) to global adjoint tomography. Dense seismic networks, such as USArray, lead to higher-resolution seismic images underneath continents. However, the imbalanced distribution of stations and sources poses challenges in global ray coverage. We adapt double-difference multitaper measurements to global adjoint tomography. We normalize each DD measurement by its number of pairs, and if a measurement has no pair, as may frequently happen for data recorded at oceanic stations, classical multitaper measurements are used. As a result, the differential measurements and pair-wise weighting strategy help balance uneven global kernel coverage. Our initial experiments with minor- and major-arc surface waves show promising results, revealing more pronounced structure near dense networks while reducing the prominence of paths towards cluster of stations. We have started using this new measurement in global adjoint inversions, addressing azimuthal anisotropy in upper mantle. Meanwhile, we are working on combining the double-difference approach with instantaneous phase measurements to emphasize contributions of scattered waves in global inversions and extending it to body waves. We will present our results and discuss challenges and future directions in the context of global tomographic inversions.

Mitigating Double Taxation in an Open Economy

OpenAIRE

Lindhe, Tobias

2001-01-01

The interaction of various methods of mitigating economic and international double taxation of corporate source income is studied within a standard neoclassical model of firm behavior. The main purpose is to determine to what extent methods effective in mitigating economic double taxation in a closed economy remain useful in an open economy where the firm's marginal investor is a foreigner. While a cut in the statutory corporate tax rate invariably reduces the cost of capital, the impact of t...

Deformed quantum double realization of the toric code and beyond

Science.gov (United States)

Padmanabhan, Pramod; Ibieta-Jimenez, Juan Pablo; Bernabe Ferreira, Miguel Jorge; Teotonio-Sobrinho, Paulo

2016-09-01

Quantum double models, such as the toric code, can be constructed from transfer matrices of lattice gauge theories with discrete gauge groups and parametrized by the center of the gauge group algebra and its dual. For general choices of these parameters the transfer matrix contains operators acting on links which can also be thought of as perturbations to the quantum double model driving it out of its topological phase and destroying the exact solvability of the quantum double model. We modify these transfer matrices with perturbations and extract exactly solvable models which remain in a quantum phase, thus nullifying the effect of the perturbation. The algebra of the modified vertex and plaquette operators now obey a deformed version of the quantum double algebra. The Abelian cases are shown to be in the quantum double phase whereas the non-Abelian phases are shown to be in a modified phase of the corresponding quantum double phase. These are illustrated with the groups Zn and S3. The quantum phases are determined by studying the excitations of these systems namely their fusion rules and the statistics. We then go further to construct a transfer matrix which contains the other Z2 phase namely the double semion phase. More generally for other discrete groups these transfer matrices contain the twisted quantum double models. These transfer matrices can be thought of as being obtained by introducing extra parameters into the transfer matrix of lattice gauge theories. These parameters are central elements belonging to the tensor products of the algebra and its dual and are associated to vertices and volumes of the three dimensional lattice. As in the case of the lattice gauge theories we construct the operators creating the excitations in this case and study their braiding and fusion properties.

Single- and double-row repair for rotator cuff tears - biology and mechanics.

Science.gov (United States)

Papalia, Rocco; Franceschi, Francesco; Vasta, Sebastiano; Zampogna, Biagio; Maffulli, Nicola; Denaro, Vincenzo

2012-01-01

We critically review the existing studies comparing the features of single- and double-row repair, and discuss suggestions about the surgical indications for the two repair techniques. All currently available studies comparing the biomechanical, clinical and the biological features of single and double row. Biomechanically, the double-row repair has greater performances in terms of higher initial fixation strength, greater footprint coverage, improved contact area and pressure, decreased gap formation, and higher load to failure. Results of clinical studies demonstrate no significantly better outcomes for double-row compared to single-row repair. Better results are achieved by double-row repair for larger lesions (tear size 2.5-3.5 cm). Considering the lack of statistically significant differences between the two techniques and that the double row is a high cost and a high surgical skill-dependent technique, we suggest using the double-row technique only in strictly selected patients. Copyright © 2012 S. Karger AG, Basel.

Stochastic cooling with a double rf system

International Nuclear Information System (INIS)

Wei, Jie.

1992-01-01

Stochastic cooling for a bunched beam of hadrons stored in an accelerator with a double rf system of two different frequencies has been investigated. The double rf system broadens the spread in synchrotron-oscillation frequency of the particles when they mostly oscillate near the center of the rf bucket. Compared with the ease of a single rf system, the reduction rates of the bunch dimensions are significantly increased. When the rf voltage is raised, the reduction rate, instead of decreasing linearly, now is independent of the ratio of the bunch area to the bucket area. On the other hand, the spread in synchrotron-oscillation frequency becomes small with the double rf system, if the longitudinal oscillation amplitudes of the particles are comparable to the dimension of the rf bucket. Consequently, stochastic cooling is less effective when the bunch area is close to the bucket area

Exchange bias in Fe/Cr double superlattices

International Nuclear Information System (INIS)

Jiang, J. S.; Felcher, G. P.; Inomata, A.; Goyette, R.; Nelson, C.; Bader, S. D.

1999-01-01

Utilizing the oscillatory interlayer exchange coupling in Fe/Cr superlattices, we have constructed ''double superlattice'' structures where a ferromagnetic (F) and an antiferromagnetic (AF) Fe/Cr superlattice are coupled through a Cr spacer. The minor hysteresis loops in the magnetization are shifted from zero field, i.e., the F superlattice is exchange biased by the AF one. The double superlattices are sputter-deposited with (211) epitaxy and possess uniaxial in-plane magnetic anisotropy. The magnitude of the bias field is satisfactorily described by the classic formula for collinear spin structures. The coherent structure and insensitivity to atomic-scale roughness makes it possible to determine the spin distribution by polarized neutron reflectivity, which confirms that the spin structure is collinear. The magnetic reversal behavior of the double superlattices suggests that a realistic model of exchange bias needs to address the process of nucleating local reverse domains

Decoherence in a double-slit quantum eraser

International Nuclear Information System (INIS)

Torres-Ruiz, F. A.; Lima, G.; Delgado, A.; Saavedra, C.; Padua, S.

2010-01-01

We study and experimentally implement a double-slit quantum eraser in the presence of a controlled decoherence mechanism. A two-photon state, produced in a spontaneous parametric down-conversion process, is prepared in a maximally entangled polarization state. A birefringent double slit is illuminated by one of the down-converted photons, and it acts as a single-photon two-qubits controlled-not gate that couples the polarization with the transversal momentum of these photons. The other photon, which acts as a which-path marker, is sent through a Mach-Zehnder-like interferometer. When the interferometer is partially unbalanced, it behaves as a controlled source of decoherence for polarization states of down-converted photons. We show the transition from wavelike to particle-like behavior of the signal photons crossing the double slit as a function of the decoherence parameter, which depends on the length path difference at the interferometer.

Exchange bias in Fe/Cr double superlattices

International Nuclear Information System (INIS)

Jiang, J. S.; Felcher, G. P.; Inomata, A.; Goyette, R.; Nelson, C. S.; Bader, S. D.

2000-01-01

Utilizing the oscillatory interlayer exchange coupling in Fe/Cr superlattices, we have constructed ''double superlattice'' structures where a ferromagnetic (F) and an antiferromagnetic (AF) Fe/Cr superlattice are coupled through a Cr spacer. The minor hysteresis loops in the magnetization are shifted from zero field, i.e., the F superlattice is exchange biased by the AF one. The double superlattices are sputter deposited with (211) epitaxy and possess uniaxial in-plane magnetic anisotropy. The magnitude of the bias field is satisfactorily described by the classic formula for collinear spin structures. The coherent structure and insensitivity to atomic-scale roughness makes it possible to determine the spin distribution by polarized neutron reflectivity, which confirms that the spin structure is collinear. The magnetic reversal behavior of the double superlattices suggests that a realistic model of exchange bias needs to address the process of nucleating local reverse domains. (c) 2000 American Vacuum Society

Thermal-hydraulic characteristics of double flat core HCLWR

International Nuclear Information System (INIS)

Sugimoto, Jun; Iwamura, Takamichi; Okubo, Tsutomu; Murao, Yoshio

1989-02-01

A thermal-hydraulic characteristics of double flat core high conversion light water reactor (HCLWR) is described. The concept of flat core proposed by Ishiguro et al. is to achieve negative void reactivity coefficient in tight lattice core, and at the same time, high conversion ratio and high burnup can be obtainable. The proposed double flat core HCLWR, based on these physical advantages and the consideration of safety assurance, aims at efficient use of the pressure vessel space to produce comparable thermal output as current 3-loop PWRs. The present work revealed the following items concerning the thermalhydraulic feasibility of the double flat core HCLWR: (1) Main thermal-hydraulic parameters of the plant can be almost the same as current PWRs, showing the use of PWR standard components without major modifications except in core region. (2) Heat removal from the fuel rod in a steady operational condition has enough margin to the critical heat flux (CHF) limit, which is evaluated with the existing CHF correlations. (3) The calculation by REFLA code shows that the maximum cladding temperature in LOCA-reflood is estimated to be far lower than the licensing criteria. It is therefore considered that the proposed double flat core HCLWR is feasible from the point of thermal-hydraulics. Since the available data base has certain applicational limit to the very short core as the present double flat core HCLWR, further detailed assessment is required. (author)

A life course examination of the physical environmental determinants of physical activity behaviour: A "Determinants of Diet and Physical Activity" (DEDIPAC) umbrella systematic literature review.

Science.gov (United States)

Carlin, Angela; Perchoux, Camille; Puggina, Anna; Aleksovska, Katina; Buck, Christoph; Burns, Con; Cardon, Greet; Chantal, Simon; Ciarapica, Donatella; Condello, Giancarlo; Coppinger, Tara; Cortis, Cristina; D'Haese, Sara; De Craemer, Marieke; Di Blasio, Andrea; Hansen, Sylvia; Iacoviello, Licia; Issartel, Johann; Izzicupo, Pascal; Jaeschke, Lina; Kanning, Martina; Kennedy, Aileen; Lakerveld, Jeroen; Chun Man Ling, Fiona; Luzak, Agnes; Napolitano, Giorgio; Nazare, Julie-Anne; Pischon, Tobias; Polito, Angela; Sannella, Alessandra; Schulz, Holger; Sohun, Rhoda; Steinbrecher, Astrid; Schlicht, Wolfgang; Ricciardi, Walter; MacDonncha, Ciaran; Capranica, Laura; Boccia, Stefania

2017-01-01

Participation in regular physical activity is associated with a multitude of health benefits across the life course. However, many people fail to meet PA recommendations. Despite a plethora of studies, the evidence regarding the environmental (physical) determinants of physical activity remains inconclusive. To identify the physical environmental determinants that influence PA across the life course. An online systematic literature search was conducted using MEDLINE, ISI Web of Science, Scopus and SPORTDiscus. The search was limited to studies published in English (January 2004 to April 2016). Only systematic literature reviews (SLRs) and meta-analyses (MAs) of observational studies, that investigated the association between physical determinants and physical activity outcomes, were eligible for inclusion. The extracted data were assessed on the importance of determinants, strength of evidence and methodological quality. The literature search identified 28 SLRs and 3 MAs on 67 physical environmental characteristics potentially related to physical activity that were eligible for inclusion. Among preschool children, a positive association was reported between availability of backyard space and outdoor toys/equipment in the home and overall physical activity. The availability of physical activity programs and equipment within schools, and neighbourhood features such as pedestrian and cyclist safety structure were positively associated with physical activity in children and adolescents. Negative street characteristics, for example, lack of sidewalks and streetlights, were negatively associated with physical activity in adults. Inconsistent associations were reported for the majority of reviewed determinants in adults. This umbrella SLR provided a comprehensive overview of the physical environment determinants of physical activity across the life course and has highlighted, particularly amongst youth, a number of key determinants that may be associated with overall

Chiral Aminophosphines as Catalysts for Enantioselective Double-Michael Indoline Syntheses

Directory of Open Access Journals (Sweden)

Ohyun Kwon

2012-05-01

Full Text Available The bisphosphine-catalyzed double-Michael addition of dinucleophiles to electron-deficient acetylenes is an efficient process for the synthesis of many nitrogen-containing heterocycles. Because the resulting heterocycles contain at least one stereogenic center, this double-Michael reaction would be even more useful if an asymmetric variant of the reaction were to be developed. Aminophosphines can also facilitate the double-Michael reaction and chiral amines are more readily available in Nature and synthetically; therefore, in this study we prepared several new chiral aminophosphines. When employed in the asymmetric double-Michael reaction between ortho-tosylamidophenyl malonate and 3-butyn-2-one, the chiral aminophosphines produced indolines in excellent yields with moderate asymmetric induction.

Experimental investigation of Cu-based, double-layered, microchannel heat exchangers

International Nuclear Information System (INIS)

Lu, Bin; Meng, W J; Mei, Fanghua

2013-01-01

Cu-based, single- and double-layered, microchannel heat exchangers (MHEs) were fabricated and assembled. Comparative measurements on liquid flow characteristics and heat transfer performance were conducted on these devices. Results were compared at the individual microchannel level as well as at the device level. The present results demonstrate that double-layered MHEs exhibit similar heat transfer performance while suffering a much lower pressure drop penalty compared to single-layered MHEs. Another Cu-based, double-layered, liquid–liquid counter-flow MHE was fabricated, assembled and tested. Results show that a low-volume, multilayered, high-performance, liquid-to-liquid MHE is achievable following the manufacturing protocols of the present double-layered, liquid–liquid counter-flow MHE. (paper)

Double-layer structure in polar mesospheric clouds observed from SOFIE/AIM

Directory of Open Access Journals (Sweden)

H. Gao

2017-02-01

Full Text Available Double-layer structures in polar mesospheric clouds (PMCs are observed by using Solar Occultation for Ice Experiment (SOFIE data between 2007 and 2014. We find 816 and 301 events of double-layer structure with percentages of 10.32 and 7.25 % compared to total PMC events, and the mean distances between two peaks are 3.06 and 2.73 km for the Northern Hemisphere (NH and Southern Hemisphere (SH respectively. Double-layer PMCs almost always have less mean ice water content (IWC than daily IWC during the core of the season, but they are close to each other at the beginning and the end. The result by averaging over all events shows that the particle concentration has obvious double peaks, while the particle radius exhibits an unexpected monotonic increase with decreasing altitude. By further analysis of the background temperature and water vapour residual profiles, we conclude that the lower layer is a reproduced one formed at the bottom of the upper layer. 56.00 and 47.51 % of all double-layer events for the NH and SH respectively have temperature enhancements larger than 2 K locating between their double peaks. The longitudinal anti-correlation between the gravity waves' (GWs' potential energies and occurrence frequencies of double-layer PMCs suggests that the double-layer PMCs tend to form in an environment where the GWs have weaker intensities.

Double Lacunary Density and Some Inclusion Results in Locally Solid Riesz Spaces

Directory of Open Access Journals (Sweden)

S. A. Mohiuddine

2013-01-01

Full Text Available We define the notions of double statistically convergent and double lacunary statistically convergent sequences in locally solid Riesz space and establish some inclusion relations between them. We also prove an extension of a decomposition theorem in this setup. Further, we introduce the concepts of double θ-summable and double statistically lacunary summable in locally solid Riesz space and establish a relationship between these notions.

A Comparative Biomechanical Analysis of 2 Double-Row, Distal Triceps Tendon Repairs

OpenAIRE

Dorweiler, Matthew A.; Van Dyke, Rufus O.; Siska, Robert C.; Boin, Michael A.; DiPaola, Mathew J.

2017-01-01

Background: Triceps tendon ruptures are rare orthopaedic injuries that almost always require surgical repair. This study tests the biomechanical properties of an original anchorless double-row triceps repair against a previously reported knotless double-row repair. Hypothesis: The anchorless double-row triceps repair technique will yield similar biomechanical properties when compared with the knotless double-row repair technique. Study Design: Controlled laboratory study. Methods: Eighteen ca...

Towards assessing corticospinal excitability bilaterally: Validation of a double-coil TMS method.

Science.gov (United States)

Grandjean, Julien; Derosiere, Gerard; Vassiliadis, Pierre; Quemener, Louise; Wilde, Ysaline de; Duque, Julie

2018-01-01

For several decades, Transcranial magnetic stimulation (TMS) has been used to monitor corticospinal excitability (CSE) changes in various contexts. Habitually, single-coil TMS is applied over one primary motor cortex (M1), eliciting motor-evoked potentials (MEPs) in a contralateral limb muscle, usually a hand effector. However, in many situations, it would be useful to obtain MEPs in both hands simultaneously, to track CSE bilaterally. Such an approach requires stimulating both M1 concurrently while avoiding interference between the two descending stimuli. We examined MEPs obtained at rest using a double-coil TMS approach where the two M1 are stimulated with a 1ms inter-pulse interval (double-coil 1ms ). MEPs were acquired using double-coil 1ms (MEP double ) or single-coil (MEP single ) TMS, at five different intensities of stimulation (100, 115, 130, 145 or 160% of the resting motor threshold, rMT). Given the 1ms inter-pulse interval in double-coil 1ms trials, MEP double were either evoked by a 1st (MEP double-1 ) or a 2nd (MEP double-2 ) TMS pulse. All MEP TYPE (MEP TYPE =MEP single , MEP double-1 and MEP double-2 ) were equivalent, regardless of the hand within which they were elicited, the intensity of stimulation or the pulse order. This method allows one to observe state-related CSE changes for the two hands simultaneously on a trial-by-trial basis. These results infer the absence of any neural interactions between the two cortico-spinal volleys with double-coil 1ms TMS. Hence, this technique can be reliably used to assess CSE bilaterally, opening new research perspectives for scientists interested in physiological markers of activity in the motor output system. Copyright © 2017 Elsevier B.V. All rights reserved.

Ion acoustic waves and double-layers in electronegative expanding plasmas

International Nuclear Information System (INIS)

Plihon, Nicolas; Chabert, Pascal

2011-01-01

Ion acoustic waves and double-layers are observed in expanding plasmas in electronegative gases, i.e., plasmas containing an appreciable fraction of negative ions. The reported experiments are performed in argon gas with a variable amount of SF 6 . When varying the amount of SF 6 , the negative ion fraction increases and three main regimes were identified previously: (i) the plasma smoothly expands at low negative ion fraction, (ii) a static double-layer (associated with an abrupt potential drop and ion acceleration) forms at intermediate negative ion fraction, (iii) double-layers periodically form and propagate (in the plasma expansion direction) at high negative ion fraction. In this paper, we show that transition phases exist in between these regimes, where fluctuations are observed. These fluctuations are unstable slow ion acoustic waves, propagating in the direction opposite to the plasma expansion. These fluctuations are excited by the most unstable eigenmodes and display turbulent features. It is suggested that the static double layer forms when the ion acoustic fluctuations become non-linearly unstable: the double layer regime being a bifurcated state of the smoothly expanding regime. For the highest negative ion fraction, a coexistence of (upstream propagating) slow ion acoustic fluctuations and (downstream) propagating double layers was observed.

A Double-Minded Fractal

Science.gov (United States)

Simoson, Andrew J.

2009-01-01

This article presents a fun activity of generating a double-minded fractal image for a linear algebra class once the idea of rotation and scaling matrices are introduced. In particular the fractal flip-flops between two words, depending on the level at which the image is viewed. (Contains 5 figures.)

Solid-Phase Synthesis of Small Molecule Libraries using Double Combinatorial Chemistry

DEFF Research Database (Denmark)

Nielsen, John; Jensen, Flemming R.

1997-01-01

The first synthesis of a combinatorial library using double combinatorial chemistry is presented. Coupling of unprotected Fmoc-tyrosine to the solid support was followed by Mitsunobu O-alkylation. Introduction of a diacid linker yields a system in which the double combinatorial step can be demons......The first synthesis of a combinatorial library using double combinatorial chemistry is presented. Coupling of unprotected Fmoc-tyrosine to the solid support was followed by Mitsunobu O-alkylation. Introduction of a diacid linker yields a system in which the double combinatorial step can...

Doubles everywhere: literary contributions to the study of the bodily self.

Science.gov (United States)

Dieguez, Sebastian

2013-01-01

The topic of the double is a hallmark of romantic, gothic, and fantastic literature. In the guise of the second self, the alter ego or the doppelgänger, fictional doubles have long fascinated critics, clinicians, and scientists. We review classical approaches to the theme and propose a broad clinical and neurocognitive framework from which to examine major instances of the motif in literature. Based on neurological disorders of the bodily self (including unilateral and whole body illusions and duplications), as well as related experimental approaches, we provide examples of literary depictions of bodily fragmentation and splitting; autoscopic hallucinations; the classical doppelgänger, second self, or heautoscopic double; the feeling of a presence; out-of-body experiences; and so-called near-death experiences. Examples include works from Guy de Maupassant, E.T.A. Hoffman, Edgar Allan Poe, Robert Louis Stevenson, Fyodor Dostoevsky, Rudyard Kipling, and others. We discuss these literary cases of doubles from a neurocognitive perspective, and suggest that common mechanisms of the bodily self are involved in the emergence of pathological illusory doubles, literary creations of the double, as well as widespread cultural and religious beliefs about the existence of doubles and the soul. Copyright © 2013 S. Karger AG, Basel.

International double (non-)taxation : comparative guidelines from European legal principles

OpenAIRE

Vijver, Van de, Anne

2015-01-01

Abstract: The principle of fairness advocates against international double taxation and international double non-taxation. Countries and international organizations (OECD, G20 and EU) have taken several initiatives against such taxation. However, these initiatives are not always effective. Also, certain legal authors question the legitimacy of the OECD and its action plan on BEPS. The essential goal of this research is to find guidelines to address international double (non-) taxation. We fir...

Vitrectomy in double-perforation gunshot injury

Directory of Open Access Journals (Sweden)

Abd El Alim Mohamed A

2013-11-01

Full Text Available Ahmed Abd El Alim MohamedOphthalmology department, Ain Shams University, Cairo, EgyptObjective: This study sought to evaluate the result of pars plana vitrectomy in patients with gunshot wounds involving double perforation.Methods: This was a retrospective, noncomparative, interventional case series.Results: Eighteen patients (18 eyes with double-perforation gunshot injuries were treated from February 2010 to March 2012. The group included 16 men (88% and two women (11%; the mean age was 24 (15–33 years. In each case, vitrectomy was scheduled 1–6 weeks after repair of the entrance site. Associated retinal detachments were observed in two eyes (11%, retinal incarceration was observed surrounding the exit site in three eyes (16%, and retention of an intraocular foreign body was observed in two cases. After a follow-up period of 8 ± 2 months, two eyes (11% had achieved visual acuity (VA of 0.5, nine eyes (50% had achieved VA between 0.5 and 0.1, and seven eyes (38% had achieved VA between 0.1 and hand movement. The main reasons for functional failure (VA 0.1 to hand movement were macular dragging (due to fibrosis at the exit site near the macula in seven cases (38%, submacular hemorrhage in four cases (22%, and epimacular fibrosis in five cases (27%. All cases developed postoperative exotropia. One case (5% developed postoperative hemorrhage. No cases exhibited signs of postoperative redetachment.Conclusion: The outcome of pars plana vitrectomy in cases with double perforations is variable. Factors including the surgeon's skill level, the time to surgery, and the efficacy of the intraocular tamponade affect the postoperative outcome.Keywords: pars plana vitrectomy, gunshot injury, double perforation

Chimney Effect Assessment of the Double-skin Facade

Institute of Scientific and Technical Information of China (English)

QIU Zhong-zhu; LI Peng; CHOW Tin-tai; REN Jian-xing; WANG Wen-huan

2009-01-01

The mathematic model of heat transfer through ventihted double glazing was verified with themeasured data,which were from a test chamber equipped with glass face temperature,solar radiation,ambient temperature,and wind speed measurement facility.Mter the model validation,the double-skin facade assess-ment was carried out through simulation with ESP-r software integrating thermal simulation and air low net work module.The air flow situation in the air gap was analyzed on the basis of the hourly air velocity simulation data within typical winter week,summer week,spring week and autumn week.The differences of chimney ef-fect in different seasons were discussed,and the thermal loads resulted from the ventilated and unventihted dou-ble skin facade were presented.

The Double Star Orbit Initial Value Problem

Science.gov (United States)

Hensley, Hagan

2018-04-01

Many precise algorithms exist to find a best-fit orbital solution for a double star system given a good enough initial value. Desmos is an online graphing calculator tool with extensive capabilities to support animations and defining functions. It can provide a useful visual means of analyzing double star data to arrive at a best guess approximation of the orbital solution. This is a necessary requirement before using a gradient-descent algorithm to find the best-fit orbital solution for a binary system.

Double burden of malnutrition: A silent driver of double burden of disease in low– and middle–income countries

Directory of Open Access Journals (Sweden)

Ivana Kolcˇic´

2012-09-01

Full Text Available Double burden of malnutrition, characterised by undernutrition among poor children and obesity among deprived adults, is a serious global problem and an important promoter of ‘double burden of disease’ which is currently affecting low– and middle–income countries. Possible ways to reduce this burden is through education on the importance of equilibrium between energy intake and expenditure; ensuring conditions for optimal fetal and early child development; and reducing poverty as one of the main drivers of both undernutrition and obesity, through empowering local communities.

Cavitation simulation and NPSH prediction of a double suction centrifugal pump

International Nuclear Information System (INIS)

Li, P; Huang, Y F; Li, J

2012-01-01

This paper illustrates the flow field numerical analysis of the double-suction centrifugal pump. For the study of the cavitation flow inside the double-suction centrifugal pump, the professional pump/motor simulation software PumpLinx and its Full Cavitation Model has been employed. According to the PumpLinx calculation result and the Cavitation damage index, the cavitation position, level and the cavitation characteristics of the double-suction centrifugal pump has been predicted. For the further objective, the simulation of the flow field in the double-suction centrifugal pump under different inlet conditions has been carried out. By the result analysis, NPSHr has been predicted; the reliability of the results has been verified by comparing with the experimental data. At the same time, this practice can provide guidance for the optimal design of double-suction pump.

Double-trace flows and the swampland

Science.gov (United States)

Giombi, Simone; Perlmutter, Eric

2018-03-01

We explore the idea that large N, non-supersymmetric conformal field theories with a parametrically large gap to higher spin single-trace operators may be obtained as infrared fixed points of relevant double-trace deformations of superconformal field theories. After recalling the AdS interpretation and some potential pathologies of such flows, we introduce a concrete example that appears to avoid them: the ABJM theory at finite k, deformed by \\int O^2, where O is the superconformal primary in the stress-tensor multiplet. We address its relation to recent conjectures based on weak gravity bounds, and discuss the prospects for a wider class of similarly viable flows. Next, we proceed to analyze the spectrum and correlation functions of the putative IR CFT, to leading non-trivial order in 1 /N. This includes analytic computations of the change under double-trace flow of connected four-point functions of ABJM superconformal primaries; and of the IR anomalous dimensions of infinite classes of double-trace composite operators. These would be the first analytic results for anomalous dimensions of finite-spin composite operators in any large N CFT3 with an Einstein gravity dual.

Bridging suture makes consistent and secure fixation in double-row rotator cuff repair.

Science.gov (United States)

Fukuhara, Tetsutaro; Mihata, Teruhisa; Jun, Bong Jae; Neo, Masashi

2017-09-01

Inconsistent tension distribution may decrease the biomechanical properties of the rotator cuff tendon after double-row repair, resulting in repair failure. The purpose of this study was to compare the tension distribution along the repaired rotator cuff tendon among three double-row repair techniques. In each of 42 fresh-frozen porcine shoulders, a simulated infraspinatus tendon tear was repaired by using 1 of 3 double-row techniques: (1) conventional double-row repair (no bridging suture); (2) transosseous-equivalent repair (bridging suture alone); and (3) compression double-row repair (which combined conventional double-row and bridging sutures). Each specimen underwent cyclic testing at a simulated shoulder abduction angle of 0° or 40° on a material-testing machine. Gap formation and tendon strain were measured during the 1st and 30th cycles. To evaluate tension distribution after cuff repair, difference in gap and tendon strain between the superior and inferior fixations was compared among three double-row techniques. At an abduction angle of 0°, gap formation after either transosseous-equivalent or compression double-row repair was significantly less than that after conventional double-row repair (p row repair (p = 0.01) at 0° abduction had significantly less difference in gap formation between the superior and inferior fixations than did conventional double-row repair. After the 30th cycle, the difference in longitudinal strain between the superior and inferior fixations at 0° abduction was significantly less with compression double-row repair (2.7% ± 2.4%) than with conventional double-row repair (8.6% ± 5.5%, p = 0.03). Bridging sutures facilitate consistent and secure fixation in double-row rotator cuff repairs, suggesting that bridging sutures may be beneficial for distributing tension equally among all sutures during double-row repair of rotator cuff tears. Copyright © 2017 The Japanese Orthopaedic Association. Published by Elsevier B

Asymptotically double lacunry equivalent sequences defined by Orlicz functions

Directory of Open Access Journals (Sweden)

Ayhan Esi

2014-04-01

Full Text Available This paper presents the following definition which is natural combition of the definition for asymptotically equivalent and Orlicz function. The two nonnegative double sequences x=(x_{k,l} and y=(y_{k,l} are said to be M-asymptotically double equivalent to multiple L provided that for every ε>0, P-lim_{k,l}M(((|((x_{k,l}/(y_{k,l}-L|/ρ=0, for some ρ>0, (denoted by x∽y and simply M-asymptotically double equivalent if L=1. Also we give some new concepts related to this definition and some inclusion theorems.

Double ionization of atomic helium under heavy ion impact

International Nuclear Information System (INIS)

Presnyakov, L.P.; Uskov, D.B.

1995-01-01

Cross sections for double ionization of helium by multiply-charged ion impact and the corresponding ratios of double-to-single ionization are presented as a sum of the contributions given by the one-step (shake-off) and two-step (TS) processes. An analytic form is found for the continuum wavefunction which is valid in both limiting cases of low and high velocities of the relative motion. Using this wavefunction, the TS cross sections are calculated within the independent-event model. The results for the ratios of double-to-single ionization show satisfactory agreement with the experimental data available. (author)

Double helix vortex breakdown in a turbulent swirling annular jet flow

Science.gov (United States)

Vanierschot, M.; Percin, M.; van Oudheusden, B. W.

2018-03-01

In this paper, we report on the structure and dynamics of double helix vortex breakdown in a turbulent annular swirling jet. Double helix breakdown has been reported previously for the laminar flow regime, but this structure has rarely been observed in turbulent flow. The flow field is investigated experimentally by means of time-resolved tomographic particle image velocimetry. Notwithstanding the axisymmetric nature of the time-averaged flow, analysis of the instantaneous three-dimensional (3D) vortical structures shows the existence of a vortex core along the central axis which breaks up into a double helix downstream. The winding sense of this double helix is opposite to the swirl direction (m =-2 ) and it is wrapped around a central vortex breakdown bubble. This structure is quite different from double helix breakdown found in laminar flows where the helix is formed in the wake of the bubble and not upstream. The double helix precesses around the central axis of the jet with a precessing frequency corresponding to a Strouhal number of 0.27.

Double Image Design in Newspaper Production

Directory of Open Access Journals (Sweden)

Mario Barišić

2010-01-01

Full Text Available In the high circulation production of daily newspapers, a double image, double information is set under the rules of Infraredesign theory (Pap et al, 2010. The management of visible and near infrared is posted with process colors for color setting configured for conventional newspaper print. The place of imprint that has delimited information in vs (Visible Spectrum and nir (Near InfraRed is called “a print with an infrared effect,” or conditionally “a print with infrared colors.” Daily newspapers, as massive carriers of information made by printing technique, are receiving a new form of presentation: printed image with a built-in invisible image.

Double Coffee opens in China

Index Scriptorium Estoniae

2009-01-01

Läti suursaadik Ingrida Levrence avas esimese Double Coffee kohviku Hiina pealinnas Pekingi südames. Rahvusvaheline kohvikukett kavatseb laieneda mõne kohviku võrra igal aastal. Seni tegutsetakse Lätis, Eestis, Leedus, Ukrainas ja Valgevenes

Twisted quantum doubles

Directory of Open Access Journals (Sweden)

Daijiro Fukuda

2004-01-01

Full Text Available Using diagrammatic pictures of tensor contractions, we consider a Hopf algebra (Aop⊗ℛλA** twisted by an element ℛλ∈A*⊗Aop corresponding to a Hopf algebra morphism λ:A→A. We show that this Hopf algebra is quasitriangular with the universal R-matrix coming from ℛλ when λ2=idA, generalizing the quantum double construction which corresponds to the case λ=idA.

Double-grooved nanofibre surfaces with enhanced anisotropic hydrophobicity.

Science.gov (United States)

Liang, Meimei; Chen, Xin; Xu, Yang; Zhu, Lei; Jin, Xiangyu; Huang, Chen

2017-11-02

This study reports a facile method for fabricating double-grooved fibrous surfaces. The primary grooves of the surface are formed by aligned fibres, while the secondary grooves are achieved by oriented nanogrooves on the fibre surface. Investigation into the formation mechanism reveals that the nanogrooves can be readily tailored through adjusting the solvent ratio and relative humidity. With this understanding, a variety of polymers have been successfully electrospun into fibres having the same nanogrooved feature. These fibres show high resemblance to natural hierarchical structures, and thereby endowing the corresponding double-grooved surface with enhanced anisotropic hydrophobicity. A water droplet at a parallel direction to the grooves exhibits a much higher contact angle and a lower roll-off angle than the droplet at a perpendicular direction. The application potential of such anisotropic hydrophobicity has been demonstrated via a fog collection experiment, in which the double-grooved surface can harvest the largest amount of water. Moreover, the fabrication method requires neither post-treatment nor sophisticated equipment, making us anticipate that the double-grooved surface would be competitive in areas where a highly ordered surface, a large surface area and an anisotropic hydrophobicity are preferred.

Spontaneous formation of non-uniform double helices for elastic rods under torsion

International Nuclear Information System (INIS)

Li, Hongyuan; Zhao, Shumin; Xia, Minggang; He, Siyu; Yang, Qifan; Yan, Yuming; Zhao, Hanqiao

2017-01-01

The spontaneous formation of double helices for filaments under torsion is common and significant. For example, the research on the supercoiling of DNA is helpful for understanding the replication and transcription of DNA. Similar double helices can appear in carbon nanotube yarns, cables, telephone wires and so forth. We noticed that non-uniform double helices can be produced due to the surface friction induced by the self-contact. Therefore an ideal model was presented to investigate the formation of double helices for elastic rods under torque. A general equilibrium condition which is valid for both the smooth surface and the rough surface situations is derived by using the variational method. By adding further constraints, the smooth and rough surface situations are investigated in detail respectively. Additionally, the model showed that the specific process of how to twist and slack the rod can determine the surface friction and hence influence the configuration of the double helix formed by rods with rough surfaces. Based on this principle, a method of manufacturing double helices with designed configurations was proposed and demonstrated. Finally, experiments were performed to verify the model and the results agreed well with the theory. - Highlights: • An ideal model is conceived to investigate the spontaneous formation of double helices for rods under torsion. • Variational method is used to obtain a universal result for the double helix formation process • Self-contact and surface friction is considered to analyze the non-uniform double helix. • A novel method of producing double helix with arbitrary configuration is proposed and demonstrated. • The experiment results agree well with the theory.

Current Status on the Development of a Double Wall Tube Steam Generator

Energy Technology Data Exchange (ETDEWEB)

Nam, Ho Yun; Choi, Byoung Hae; Kim, Jong Man; Kim, Byung Ho

2007-12-15

A fast reactor, which uses sodium as a coolant, has a lot of merits as a next generation nuclear reactor. However, the possibility of a sodium-water reaction occurrence hinders the commercialization of this reactor. As one way to improve the reliability of a steam generator, a double-wall tube steam generator is being developed in GEN-4 program. In this report, the current state of the technical developments for a double-wall tube steam generator are reviewed and a future plan for the development of a double-wall tube steam generator is established. The current focuses of this research are an improvement of the heat transfer capability for a double-wall tube and the development of a proper leak detection method for the failure of a double-wall tube during a reactor operation. The ideal goal is an on-line leak detection of a double wall tube to prevent the sodium-water reaction. However, such a method is not developed as yet. An alternative method is being used to improve the reliability of a steam generator by performing a non-destructive test of a double wall tube during the refueling period of a reactor. In this method a straight double wall tube is employed to perform this test easily, but has a difficulty regarding an absorption of a thermal expansion of the used materials. If an on-line leak detection method is developed, the demerits of a straight double-wall tube are avoided by using a helical type double-wall tube, and the probability of a sodium-water reaction can be reduced to a level less than the design-based accident.

Spontaneous formation of non-uniform double helices for elastic rods under torsion

Energy Technology Data Exchange (ETDEWEB)

Li, Hongyuan [Department of Applied Physics, School of Science, Xi' an Jiaotong University, Shaanxi 710049 (China); Zhao, Shumin, E-mail: zhaosm@mail.xjtu.edu.cn [Department of Applied Physics, School of Science, Xi' an Jiaotong University, Shaanxi 710049 (China); Xia, Minggang [Department of Optical Information Science and Technology, School of Science, Xi' an Jiaotong University, 710049 (China); Laboratory of Nanostructure and Physics Properties, School of Science, Xi' an Jiaotong University, 710049 (China); He, Siyu [Department of Applied Physics, School of Science, Xi' an Jiaotong University, Shaanxi 710049 (China); Yang, Qifan [Department of Biomedical Engineering, School of Life Science and Technology, Xi' an Jiaotong University, Shaanxi 710049 (China); Yan, Yuming [Department of Electrical Engineering and Automation, School of Electrical Engineering, Xi' an Jiaotong University, Shaanxi 710049 (China); Zhao, Hanqiao [Department of Biomedical Engineering, School of Life Science and Technology, Xi' an Jiaotong University, Shaanxi 710049 (China)

2017-02-19

The spontaneous formation of double helices for filaments under torsion is common and significant. For example, the research on the supercoiling of DNA is helpful for understanding the replication and transcription of DNA. Similar double helices can appear in carbon nanotube yarns, cables, telephone wires and so forth. We noticed that non-uniform double helices can be produced due to the surface friction induced by the self-contact. Therefore an ideal model was presented to investigate the formation of double helices for elastic rods under torque. A general equilibrium condition which is valid for both the smooth surface and the rough surface situations is derived by using the variational method. By adding further constraints, the smooth and rough surface situations are investigated in detail respectively. Additionally, the model showed that the specific process of how to twist and slack the rod can determine the surface friction and hence influence the configuration of the double helix formed by rods with rough surfaces. Based on this principle, a method of manufacturing double helices with designed configurations was proposed and demonstrated. Finally, experiments were performed to verify the model and the results agreed well with the theory. - Highlights: • An ideal model is conceived to investigate the spontaneous formation of double helices for rods under torsion. • Variational method is used to obtain a universal result for the double helix formation process • Self-contact and surface friction is considered to analyze the non-uniform double helix. • A novel method of producing double helix with arbitrary configuration is proposed and demonstrated. • The experiment results agree well with the theory.

Long-term stability of a one-dimensional current-driven double layer

International Nuclear Information System (INIS)

Hori, N.; Yamamoto, T.

1988-01-01

Long-term (>an electron transit time over the system) stability of a one-dimensional current-driven double layer is studied by numerical experiments using particles. In these experiments, the potential difference across the system is self-consistently determined by the space charge distributions inside the system. Each boundary of the system supplies a nondrifting half-Maxwellian plasma. The current density is increased by increasing the number density of the source plasma at the injection (right) boundary. A double layer can be developed by injection of a sufficiently high current density. For a fixed level of current injection, plasmas carrying no current with various densities (n/sup ts/ 0 ) are loaded on the left side of the system. Whether or not the generated double layer can maintain its potential drop for a long period depends on the density (n/sup ts/ 0 ) relative to the initial density (n/sup */ 0 ) near the injection boundary: (1) the double layer is found to grow when n/sup ts/ 0 = n/sup */ 0 ; (2) the steady double layer is seen for a long period when n/sup ts/ 0 approx. >n/sup */ 0 ; (3) the double layer is found to decay when n/sup ts/ 0 is even higher than n/sup */ 0 . A new concept of the current polarizability P/sub c/ = J/n/sup number/ is introduced for understanding these results, where J is the current density flowing through the double layer and n/sup number/ is the plasma density at the injection front, i.e., the low-potential edge of the double layer

Ab-initio validation of a simple heuristic expression for the sequential-double-ionization contribution to the double ionization of helium by ultrashort XUV pulses

International Nuclear Information System (INIS)

Liu, Aihua; Thumm, Uwe

2015-01-01

We study two-photon double ionization of helium by short XUV pulses by numerically solving the time-dependent Schrodinger equation in full dimensionality within a finite-element discrete-variable-representation scheme. Based on the emission asymmetries in joint photoelectron angular distributions, we identify sequential and non-sequential contributions to two-photon double ionization for ultrashort pulses whose spectrum overlaps the sequential (ħω > 54.4 eV) and non-sequential (39.5 eV < ħω < 54.4 eV) double-ionization regimes. (paper)

DNA-like double helix formed by peptide nucleic acid

DEFF Research Database (Denmark)

Wittung, P; Nielsen, Peter E.; Buchardt, O

1994-01-01

Although the importance of the nucleobases in the DNA double helix is well understood, the evolutionary significance of the deoxyribose phosphate backbone and the contribution of this chemical entity to the overall helical structure and stability of the double helix is not so clear. Peptide nucleic...

Consensus double reading of mammograms in private practice

International Nuclear Information System (INIS)

Pacher, B.; Tscherney, R.; Litmann-Rowenta, B.; Liskutin, J.; Mazewski, I.; Leitner, H.; Tscholakoff, D.

2004-01-01

Purpose: To evaluate retrospectively the results of consensus double reading of mammograms in a private practice for a period of 1.5 years (November 2001 to March 2003). Materials and Method: Two independent experts with dedicated training read all mammograms on a weekly basis. All mammograms including sonographic examinations were evaluated independently and categorized using the Bl-RADS classification. The achieved consensus included a possible recommendation for recall or therapy. A total of 3936 mammograms and 1912 sonography studies were evaluated. All cases with BI-RADS 4 and 5 categories were compared with the histologic results. For a period of three months, the acceptance of double reading including a delay of the final report by one week was tested with a questionnaire and informed consent sheet. Results: BI-RADS categories 4 and 5 were found in 57 cases, with 41 consensus results by two independent readers and 26 carcinomas verified by histology. No consensus could be reached in 16 patients, of which 10 had a final histologic result, with 5 benign lesions and 5 carcinomas of less than 1 cm in diameter. Clinical symptoms or alterations were absent in all patients. The 5 carcinomas were discovered by the double reading procedure. The result of the questionnaire (695 questionnaires) showed a refusal rate of 0.7%, with only 5 women refusing the opportunity of double reading their mammograms. Conclusion: Double reading of mammograms by independent experts is feasible, shows a measurable increase in quality and is accepted by almost all women. (orig.)

Numerical Investigation of Double-Cone Flows with High Enthalpy Effects

Science.gov (United States)

Nompelis, I.; Candler, G. V.

2009-01-01

A numerical study of shock/shock and shock/boundary layer interactions generated by a double-cone model that is placed in a hypersonic free-stream is presented. Computational results are compared with the experimental measurements made at the CUBRC LENS facility for nitrogen flows at high enthalpy conditions. The CFD predictions agree well with surface pressure and heat-flux measurements for all but one of the double-cone cases that have been studied by the authors. Unsteadiness is observed in computations of one of the LENS cases, however for this case the experimental measurements show that the flowfield is steady. To understand this discrepancy, several double-cone experiments performed in two different facilities with both air and nitrogen as the working gas are examined in the present study. Computational results agree well with measurements made in both the AEDC tunnel 9 and the CUBRC LENS facility for double-cone flows at low free-stream Reynolds numbers where the flow is steady. It is shown that at higher free- stream pressures the double-cone simulations develop instabilities that result in an unsteady separation.

The double cortical line: a sign of osteopenia

International Nuclear Information System (INIS)

Lamb, C.R.

1990-01-01

The double cortical line is a radiographic sign of osteopenia which results from intracortical resorption of bone. This sign is frequently seen in humans with osteopenia but has received minimal attention in the veterinary literature. This report describes the double cortical line in cases of senile osteopenia, nutritional secondary hyperparathyroidism, suspected renal secondary hyperparathyroidism and in the acetabulum following triple pelvic osteotomy for hip dysplasia

Double Hopf bifurcation in delay differential equations

Directory of Open Access Journals (Sweden)

Redouane Qesmi

2014-07-01

Full Text Available The paper addresses the computation of elements of double Hopf bifurcation for retarded functional differential equations (FDEs with parameters. We present an efficient method for computing, simultaneously, the coefficients of center manifolds and normal forms, in terms of the original FDEs, associated with the double Hopf singularity up to an arbitrary order. Finally, we apply our results to a nonlinear model with periodic delay. This shows the applicability of the methodology in the study of delay models arising in either natural or technological problems.

(r, s-(τ12,τ12*-θ-Generalized double fuzzy closed sets in bitopological spaces

Directory of Open Access Journals (Sweden)

E. El-Sanousy

2016-10-01

Full Text Available In this paper, we introduce the notion of (r, s-(i, j-θ-generalized double fuzzy closed sets in double fuzzy bitopological spaces. A new θ-double fuzzy closure C12θ on double fuzzy bitopological spaces by using double supra fuzzy topological spaces are defined. Furthermore, generalized double fuzzy θ-continuous (resp. irresolute and double fuzzy strongly θ-continuous mappings are introduced and some of their properties studied.

EFFECTIVENESS OF DOUBLE WASH SWIM-UP VERSUS DOUBLE DENSITY GRADIENT SWIM-UP TECHNIQUE OF SPERM PREPARATION IN IN VITRO FERTILISATION

OpenAIRE

Srinivas Sangisapu; Sandeep Karunakaran; Ashok Kumar Pillai

2017-01-01

BACKGROUND Recovery of optimum number of good quality of spermatozoa is an important component of In Vitro Fertilisation (IVF). This is achieved by sperm preparation methods involving separation and recovery of capacitated sperms. Double Wash Swim-up (DWSU) and Double Density Gradient Swim-up (DDGSU) are two most accepted methods. Cochrane systematic review (2007) finds no clear benefit of one method over the other in Intrauterine Insemination (IUI). Systematic review on effective...

Transmission loss of double wall panels containing Helmholtz resonators

Science.gov (United States)

Prydz, R. A.; Kuntz, H. L.; Morrow, D. L.; Wirt, L. S.

Data and an analysis are presented on the use of Helholtz resonators in double wall panels (i.e., aircraft sidewalls). Several wall materials and resonator configurations were tested, and the resonators were found to substantially increase the transmission loss of the double wall system at the tuning frequency.

Polysulfide intercalated layered double hydroxides for metal capture applications

Energy Technology Data Exchange (ETDEWEB)

Kanatzidis, Mercouri G.; Ma, Shulan

2017-04-04

Polysulfide intercalated layered double hydroxides and methods for their use in vapor and liquid-phase metal capture applications are provided. The layered double hydroxides comprise a plurality of positively charged host layers of mixed metal hydroxides separated by interlayer spaces. Polysulfide anions are intercalated in the interlayer spaces.

Study of double scattering effect in antiproton--deuteron annihilation

International Nuclear Information System (INIS)

Zemany, P.D.

1975-01-01

The double scattering process in the deuteron is investigated for the reaction anti pd → p/sub s/ + mesons. About 30 percent of the apparent anti pn annihilations are involved in double scattering. A model which describes the properties of protons emerging from apparent anti pn annihilations is presented

Design of double tape recorder data acquisition system

International Nuclear Information System (INIS)

Guo Tianrui; Du Yifei

1995-01-01

In the data acquisition system supported by the microcomputer tape recorder, as the acquisition speed is often limited by the low speed of tape recorder, so a double tape recorder system is designed. In this system, two tape recorders are used in on-line acquisition system simultaneously. One DMA channel used is one designed for soft disk driver, another DMA channel used is one retained for user. By this way, the speed of tape writing could be increased to nearly twice as much. In order to prevent the data confusion, the authors open two data buffers in system and write different mark in each buffer, then write the data block to two tape recorders according to the mark. The system complies with the principle: 'Double write, Double read'

Development of ion-acoustic double layers through ion-acoustic fluctuations

International Nuclear Information System (INIS)

Sekar, A.N.; Saxena, Y.C.

1985-01-01

Experimental results on the formation of ion acoustic double layers resembling asymmetric ion-holes are presented. In a double plasma device, modified suitably to inject electron beam into the target plasma, modulation of the beam through step potential leads to excitation of ion-acoustic fluctuation. The ion-acoustic fluctuation, growing away from the grids separating source and target plasmas, developed into weak asymmetric ion-acoustic double layer. The observations are in qualitative agreement with theoretical models and computer simulations. (author)

The Nature of Double-peaked [O III] Active Galactic Nuclei

Science.gov (United States)

Fu, Hai; Yan, Lin; Myers, Adam D.; Stockton, Alan; Djorgovski, S. G.; Aldering, G.; Rich, Jeffrey A.

2012-01-01

Active galactic nuclei (AGNs) with double-peaked [O III] lines are suspected to be sub-kpc or kpc-scale binary AGNs. However, pure gas kinematics can produce the same double-peaked line profile in spatially integrated spectra. Here we combine integral-field spectroscopy and high-resolution imaging of 42 double-peaked [O III] AGNs from the Sloan Digital Sky Survey to investigate the constituents of the population. We find two binary AGNs where the line splitting is driven by the orbital motion of the merging nuclei. Such objects account for only ~2% of the double-peaked AGNs. Almost all (~98%) of the double-peaked AGNs were selected because of gas kinematics; and half of those show spatially resolved narrow-line regions that extend 4-20 kpc from the nuclei. Serendipitously, we find two spectrally unresolved binary AGNs where gas kinematics produced the double-peaked [O III] lines. The relatively frequent serendipitous discoveries indicate that only ~1% of binary AGNs would appear double-peaked in Sloan spectra and 2.2+2.5 -0.8% of all Sloan AGNs are binary AGNs. Therefore, the double-peaked sample does not offer much advantage over any other AGN samples in finding binary AGNs. The binary AGN fraction implies an elevated AGN duty cycle (8+8 -3%), suggesting galaxy interactions enhance nuclear accretion. We illustrate that integral-field spectroscopy is crucial for identifying binary AGNs: several objects previously classified as "binary AGNs" with long-slit spectra are most likely single AGNs with extended narrow-line regions (ENLRs). The formation of ENLRs driven by radiation pressure is also discussed. Some of the data presented herein were obtained at the W.M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation.

CoCr/NiFe double layers studied by FMR and VSM

NARCIS (Netherlands)

Stam, M.T.H.C.W.; Gerritsma, G.J.; Lodder, J.C.; Popma, T.J.A.

1987-01-01

CoCr/NiFe double layers were investigated by FMR and VSM. The FMR linewidth of NiFe of the double layer is about twice that of a single NiFe layer. The resonance field is the same in both cases. Using the VSM the coercive field of the CoCr layer of the double layer was obtained. It is approximately

Some double sequence spaces of interval numbers defined by Orlicz function

Directory of Open Access Journals (Sweden)

Ayhan Esi

2014-10-01

Full Text Available In this paper we introduce some interval valued double sequence spaces defined by Orlicz function and study different properties of these spaces like inclusion relations, solidity, etc. We establish some inclusion relations among them. Also we introduce the concept of double statistical convergence for interval number sequences and give an inclusion relation between interval valued double sequence spaces.

Grand unification and the double beta-decay

International Nuclear Information System (INIS)

Faessler, A.

1992-01-01

Models of the unification of the electroweak and the strong interaction predict that the neutrino is a Majorana particle and therefore essentially identical with its own antiparticle. In such grand unified models the neutrino has also a finite mass and a slight right-handed weak interaction, since the model is left-right symmetric. These models have also left handed and right-handed vector bosons to mediate the weak interactions. If these models are correct the neutrinoless double beta-decay is feasable. Thus if one finds the neutrinoless double beta-decay one knows that the standard model can not be correct in which the neutrino is a Dirac particle and therefore different from its antiparticle. Although the neutrinoless double beta-decay has not been seen it is possible to extract from the lower limits of the lifetime against the double neutrinoless beta-decay upper limits for the effective electron-neutrino mass and for the effective mixing angle of the right-handed and the left-handed vector bosons mediating the weak interaction. One also can obtain an effective upper limit for the mass ratio of the light and the heavy vector bosons. The extraction of this physical quantities from the data is made difficult due to the fact that the weak interaction must not be diagonal in the representation of the mass matrix of the six neutrinos requested by such left-right symmetric models. (author)

Double {Lambda}-hypernuclei at the PANDA experiment

Energy Technology Data Exchange (ETDEWEB)

Sanchez Lorente, Alicia, E-mail: a.sanchez@gsi.de [Helmholtz Institut Mainz (Germany); Collaboration: P-bar ANDA Collaboration

2012-12-15

Hypernuclear research will be one of the main topics addressed by the PANDA experiment at the planned Facility for Antiproton and Ion Research FAIR at Darmstadt (Germany). Thanks to the use of stored p-bar beams, copious production of double {Lambda} hypernuclei is expected at the PANDA experiment, which will enable high precision {gamma} spectroscopy of such nuclei for the first time. At PANDA excited states of {Xi}{sup }- hypernuclei will be used as a starting point for the formation of double {Lambda} hypernuclei. In order to predict the yield of particle stable double hypernuclei a microcanonical decay model was developed. For the detection of these nuclei, a devoted hypernuclear detector setup is planned. This set-up consists, in addition to the general purpose of the PANDA set-up, of a primary nuclear target for the production of {Xi}{sup -} + {Xi}-bar pairs, a secondary active target for the hypernuclei formation and the identification of associated decay products and a germanium array detector to perform {gamma} spectroscopy. Furthermore, the presence of {Xi}-bar can be used as an alternative to tag the strangeness in the {Xi}{sup -} + {Xi}-bar. All systems need to operate in the presence of a high magnetic field and a large hadronic background. In the present talk details concerning simulations, the identification procedure of double hypernuclei and the suppression of background will be presented. In addition, the present status of the detector developments for this programme will be briefly given.

Magnetoresistance stories of double perovskites

Indian Academy of Sciences (India)

grain surfaces have also been proposed to act as tunnel barriers in Sr2FeMoO6. ... these double perovskites, a gradual decrease in the low-field MR and saturation ... simultaneously, and therefore serious material engineering was needed.

Biomechanical comparison of double-row locking plates versus single- and double-row non-locking plates in a comminuted metacarpal fracture model.

Science.gov (United States)

Gajendran, Varun K; Szabo, Robert M; Myo, George K; Curtiss, Shane B

2009-12-01

Open or unstable metacarpal fractures frequently require open reduction and internal fixation. Locking plate technology has improved fixation of unstable fractures in certain settings. In this study, we hypothesized that there would be a difference in strength of fixation using double-row locking plates compared with single- and double-row non-locking plates in comminuted metacarpal fractures. We tested our hypothesis in a gap metacarpal fracture model simulating comminution using fourth-generation, biomechanical testing-grade composite sawbones. The metacarpals were divided into 6 groups of 15 bones each. Groups 1 and 4 were plated with a standard 6-hole, 2.3-mm plate in AO fashion. Groups 2 and 5 were plated with a 6-hole double-row 3-dimensional non-locking plate with bicortical screws aimed for convergence. Groups 3 and 6 were plated with a 6-hole double-row 3-dimensional locking plate with unicortical screws. The plated metacarpals were then tested to failure against cantilever apex dorsal bending (groups 1-3) and torsion (groups 4-6). The loads to failure in groups 1 to 3 were 198 +/- 18, 223 +/- 29, and 203 +/- 19 N, respectively. The torques to failure in groups 4 to 6 were 2,033 +/- 155, 3,190 +/- 235, and 3,161 +/- 268 N mm, respectively. Group 2 had the highest load to failure, whereas groups 5 and 6 shared the highest torques to failure (p row plates had equivalent bending and torsional stiffness, significantly higher than observed for the single-row non-locking plate. No other statistical differences were noted between groups. When subjected to the physiologically relevant forces of apex dorsal bending and torsion in a comminuted metacarpal fracture model, double-row 3-dimensional non-locking plates provided superior stability in bending and equivalent stability in torsion compared with double-row 3-dimensional locking plates, whereas single-row non-locking plates provided the least stability.

Introductory remarks on double beta decay and nuclear physics

International Nuclear Information System (INIS)

Rosen, S.P.

1986-01-01

The particle physics aspects of double beta decay and the theory of the phenomenon are briefly reviewed. The distinction between Dirac and Majorana neutrinos is drawn by comparing the neutrino that accompanies a negatively charged lepton in some hadronic decay process with that which accompanies a positively charged lepton in some other decay process. Two modes of double beta decay are examined - one emitting two neutrinos and the other emitting no neutrinos. What can be learned from the existing data on double beta decay is considered, de-emphasizing the question of bounds on neutrino mass and concentrating on the properties of the phenomenon itself. Possible future experiments are anticipated. 16 refs

A double-pass interferometer for measurement of dimensional changes

International Nuclear Information System (INIS)

Ren, Dongmei; Lawton, K M; Miller, J A

2008-01-01

A double-pass interferometer was developed for measuring dimensional changes of materials in a nanoscale absolute interferometric dilatometer. This interferometer realized the double-ended measurement of a sample using a single-detection double-pass interference system. The nearly balanced design, in which the measurement beam and the reference beam have equal optical path lengths except for the path difference caused by the sample itself, makes this interferometer have high stability, which is verified by the measurement of a quasi-zero-length sample. The preliminary experiments and uncertainty analysis show that this interferometer should be able to measure dimensional changes with characteristic uncertainty at the nanometer level

Improvement in transmission loss of aircraft double wall with resonators

Science.gov (United States)

Sun, Jincai; Shi, Liming; Ye, Xining

1991-08-01

A little volume low frequency resonator applicable to double-wall configuration of propeller-driven aircraft was designed on the basis of the principle of Helmholtz resonator. The normal incidence absorption coefficient of the various single resonator has been measured. The agreement between theoretical and experimental results is encouraging. An array of resonators whose resonant frequency at 85 Hz and 160 Hz, respectively, are installed between aircraft double-panel, and it has been shown that transmission loss of the double wall structure with resonators improve 4 dB and 6.5 dB in 1/3rd octave bandwidth at 80 Hz and 160 Hz center frequency, respectively, and 5 dB and 7 dB at resonant frequencies, compared with that of the double wall configuration without resonators.

Study on dynamic deformation synchronized measurement technology of double-layer liquid surfaces

Science.gov (United States)

Tang, Huiying; Dong, Huimin; Liu, Zhanwei

2017-11-01

Accurate measurement of the dynamic deformation of double-layer liquid surfaces plays an important role in many fields, such as fluid mechanics, biomechanics, petrochemical industry and aerospace engineering. It is difficult to measure dynamic deformation of double-layer liquid surfaces synchronously for traditional methods. In this paper, a novel and effective method for full-field static and dynamic deformation measurement of double-layer liquid surfaces has been developed, that is wavefront distortion of double-wavelength transmission light with geometric phase analysis (GPA) method. Double wavelength lattice patterns used here are produced by two techniques, one is by double wavelength laser, and the other is by liquid crystal display (LCD). The techniques combine the characteristics such as high transparency, low reflectivity and fluidity of liquid. Two color lattice patterns produced by laser and LCD were adjusted at a certain angle through the tested double-layer liquid surfaces simultaneously. On the basis of the refractive indexes difference of two transmitted lights, the double-layer liquid surfaces were decoupled with GPA method. Combined with the derived relationship between phase variation of transmission-lattice patterns and out-of plane heights of two surfaces, as well as considering the height curves of the liquid level, the double-layer liquid surfaces can be reconstructed successfully. Compared with the traditional measurement method, the developed method not only has the common advantages of the optical measurement methods, such as high-precision, full-field and non-contact, but also simple, low cost and easy to set up.

High efficiency double sided solar cells

International Nuclear Information System (INIS)

Seddik, M.M.

1990-06-01

Silicon technology state of the art for single crystalline was given to be limited to less than 20% efficiency. A proposed new form of photovoltaic solar cell of high current high efficiency with double sided structures has been given. The new forms could be n ++ pn ++ or p ++ np ++ double side junctions. The idea of double sided devices could be understood as two solar cells connected back-to-back in parallel electrical connection, in which the current is doubled if the cell is illuminated from both sides by a V-shaped reflector. The cell is mounted to the reflector such that each face is inclined at an angle of 45 deg. C to each side of the reflector. The advantages of the new structure are: a) High power devices. b) Easy to fabricate. c) The cells are used vertically instead of horizontal use of regular solar cell which require large area to install. This is very important in power stations and especially for satellite installation. If the proposal is made real and proved to be experimentally feasible, it would be a new era for photovoltaic solar cells since the proposal has already been extended to even higher currents. The suggested structures could be stated as: n ++ pn ++ Vp ++ np ++ ;n ++ pn ++ Vn ++ pn ++ ORp ++ np ++ Vp ++ np ++ . These types of structures are formed in wedged shape to employ indirect illumination by either parabolic; conic or V-shaped reflectors. The advantages of these new forms are low cost; high power; less in size and space; self concentrating; ... etc. These proposals if it happens to find their ways to be achieved experimentally, I think they will offer a short path to commercial market and would have an incredible impact on solar cell technology and applications. (author). 12 refs, 5 figs

Double Beta Decay Experiments

International Nuclear Information System (INIS)

Piepke, A.

2005-01-01

The experimental observation of neutrino oscillations and thus neutrino mass and mixing gives a first hint at new particle physics. The absolute values of the neutrino mass and the properties of neutrinos under CP-conjugation remain unknown. The experimental investigation of the nuclear double beta decay is one of the key techniques for solving these open problems

Proceedings of the LAMPF workshop on pion double charge exchange

International Nuclear Information System (INIS)

Baer, H.W.; Leitch, M.J.

1985-09-01

Experimental and theoretical aspects of double-analog, nonanalog, and continuum pion double charge exchange in the 50- to 310-MeV energy range are covered. Separate abstracts were prepared for 22 papers in these proceedings

Bilateral double level tibial lengthening in dwarfism.

Science.gov (United States)

Burghardt, Rolf D; Yoshino, Koichi; Kashiwagi, Naoya; Yoshino, Shigeo; Bhave, Anil; Paley, Dror; Herzenberg, John E

2015-12-01

Outcome assessment after double level tibial lengthening in patients with dwarfism. Fourteen patients with dwarfism were analyzed after bilateral simultaneous double level tibial lengthening. Average age was 15.1 years. Average lengthening was 13.5 cm. The two levels were lengthened by an average of 7.5 cm proximally and 6.0 cm distally. Concomitant deformities were also addressed during lengthening. External fixation treatment time averaged 8.8 months. Healing index averaged 0.7 months/cm. Bilateral tibial lengthening for dwarfism is difficult, but the results are usually quite gratifying.

Spin-filtering junctions with double ferroelectric barriers

International Nuclear Information System (INIS)

Yan, Ju; Ding-Yu, Xing

2009-01-01

An FS/FE/NS/FE/FS double tunnel junction is suggested to have the ability to inject, modulate and detect the spin-polarized current electrically in a single device, where FS is the ferromagnetic semiconductor electrode, NS is the nonmagnetic semiconductor, and FE the ferroelectric barrier. The spin polarization of the current injected into the NS region can be switched between a highly spin-polarized state and a spin unpolarized state. The high spin polarization may be detected by measuring the tunneling magnetoresistance ratio of the double tunnel junction

A Wortmannin-Cetuximab As A Double Drug

Science.gov (United States)

Smith, R. Adam; Yuan, Hushan; Weissleder, Ralph; Cantley, Lewis C.; Josephson, Lee

2012-01-01

Double drugs are obtained when two pharmacologically active entities are covalently joined to improve potency. We conjugated the viridin Wm with a self-activating linkage to cetuximab and demonstrated the retention of immunoreactivity by the conjugate. Though cetuximab lacked a growth inhibitory activity against A549 cells, the Wmcetuximab conjugate had an anti-proliferative IC50 of 155 nM in vitro. The chemistry of attaching a self-releasing Wm to clinically approved antibodies is general and, in selected instances, may yield antibody-based double drugs with improved efficacy. PMID:19883074

The double contrast examination of the colon

International Nuclear Information System (INIS)

Welin, S.; Welin, G.

1980-01-01

The double contrast method has been modified in order to get a more detailed picture of the mucous membrane of the colon. The method has been employed at Malmoe hospital since 1953. The method and its diagnostic application in cases of adenoids, villiferous tumours, diverticula, Crohn's disease, ulcerating colitis, and deformation of the rectum/sigma junction due to external endometriosis and peritoneal carcinosis are described. The diagnostic values of the double contrast method and colposcopy/biopsy of the colon are compared. The two methods are found to be complementary. (MG) [de

The International Double Taxation – causes and avoidance

OpenAIRE

Nicoleta Barbuta-Misu; Florin Tudor

2009-01-01

The politics and tax legislation being a manifestation of strict sovereignty of the State, the phenomenon of double taxation occurs frequently representing a difficult poison for the foreign trade activity, especially hindering investments abroad, technology transfer or proliferation outside of the state of the companies’ branches. Therefore, international legal double taxation, by the repeated taxation of the income, it is an obstacle to the development of economic relations between states, ...

Electrochemical properties of double wall carbon nanotube electrodes

OpenAIRE

Pumera, Martin

2007-01-01

AbstractElectrochemical properties of double wall carbon nanotubes (DWNT) were assessed and compared to their single wall (SWNT) counterparts. The double and single wall carbon nanotube materials were characterized by Raman spectroscopy, scanning and transmission electron microscopy and electrochemistry. The electrochemical behavior of DWNT film electrodes was characterized by using cyclic voltammetry of ferricyanide and NADH. It is shown that while both DWNT and SWNT were significantly funct...

Generation mechanism and properties of plasma double layers

International Nuclear Information System (INIS)

Sanduloviciu, M.; Lozneanu, E.

1985-01-01

The generation mechanism of plasma double layers is studied surveying the results of some experiments. The main mechanism is the same in the cases of collisional and collisionless plasmas. Inelastic quantum collision processes taking place between plasma electrons, accelerated in a local field up to near the same oriented velocity and the neutral particles of the background gases create the necessary conditions for double layer formation. (D.Gy.)

Double Simplex - Visualizing particles and their interactions seminar

CERN Multimedia

CERN. Geneva HR-RFA

2006-01-01

The double simplex is a new way to envision the particles and interactions through a three-dimensional construction intended to serve as an invitation to narrative and a spur to curiosity. My goal is to represent what we know is true, what we hope might be true, and what we don't know. Constructing the double simplex expresses the spirit of play, of successive approximations, that animates the way scientists work.

The double Chooz hardware trigger system

Energy Technology Data Exchange (ETDEWEB)

Cucoanes, Andi; Beissel, Franz; Reinhold, Bernd; Roth, Stefan; Stahl, Achim; Wiebusch, Christopher [RWTH Aachen (Germany)

2008-07-01

The double Chooz neutrino experiment aims to improve the present knowledge on {theta}{sub 13} mixing angle using two similar detectors placed at {proportional_to}280 m and respectively 1 km from the Chooz power plant reactor cores. The detectors measure the disappearance of reactor antineutrinos. The hardware trigger has to be very efficient for antineutrinos as well as for various types of background events. The triggering condition is based on discriminated PMT sum signals and the multiplicity of groups of PMTs. The talk gives an outlook to the double Chooz experiment and explains the requirements of the trigger system. The resulting concept and its performance is shown as well as first results from a prototype system.

Nuclear aspects of double-beta decay

International Nuclear Information System (INIS)

Stoica, S.; Paun, V.

2002-01-01

Calculations of the neutrinoless double-beta decay (0νββ) matrix elements are performed with the second quasi random phase approximation (SQRPA) method for several nuclei. The results display a weak dependence on the single particle basis used and the Ikeda sum rule is fulfilled with good accuracy. Comparing our calculations with similar ones performed with other QRPA-based methods we estimate the accuracy of these methods in the prediction of the (0νββ) decay matrix elements and neutrino mass parameter, which is settled to about 50% from their calculated values. Taking the most recent experimental limits for the neutrinoless double beta decay half-lives, we also deduced new limits for the neutrino mass parameter. (authors)

Double beta decays and related subjects for particle and nuclear physics

International Nuclear Information System (INIS)

Ejiri, Hiroyasu

1991-01-01

Present status and some perspectives in 1990's are briefly given on double beta decays and related subjects. Subjects discussed are as follows I) Double beta decays without neutrinos, which require lepton number non-conservations and finite neutrino mass. II) Double beta decays followed by two neutrinos. III) Double weak processes with strangeness change ΔS = 2, leading to the H particle with 6 quarks of ss uu dd. IV) Charge non-conservation and electron decays. These are very rare nuclear processes studied by Ultra RAre-process NUclear Spectroscopy (URANUS). It is shown that URANUS is an important detector frontier of non-accelerator nuclear physics in 1990's. (orig.)

Considerations for double-hand replantation in a resource-constrained healthcare facility

Directory of Open Access Journals (Sweden)

Bibhuti Bhusan Nayak

2016-01-01

Full Text Available Bilateral-hand amputation is extremely rare and double-hand replantation is even rarer. Only one case of successful double replantation at arm level has been reported from India. We present a case of double-hand replantation at proximal palmar level in a young adult executed in a small nursing home. The patient presented 5 h after injury with limbs preserved well in ice. There were difficulties in executing such an unusual case in a small nursing home set-up. The patient is performing his activities of daily living and basic functions independently. We share our experience of this double-hand replantation with special emphasis on problems encountered.

Obliquely Propagating Non-Monotonic Double Layer in a Hot Magnetized Plasma

International Nuclear Information System (INIS)

Kim, T.H.; Kim, S.S.; Hwang, J.H.; Kim, H.Y.

2005-01-01

Obliquely propagating non-monotonic double layer is investigated in a hot magnetized plasma, which consists of a positively charged hot ion fluid and trapped, as well as free electrons. A model equation (modified Korteweg-de Vries equation) is derived by the usual reductive perturbation method from a set of basic hydrodynamic equations. A time stationary obliquely propagating non-monotonic double layer solution is obtained in a hot magnetized-plasma. This solution is an analytic extension of the monotonic double layer and the solitary hole. The effects of obliqueness, external magnetic field and ion temperature on the properties of the non-monotonic double layer are discussed

Performance requirements for the double-shell tank system: Phase 1

International Nuclear Information System (INIS)

Claghorn, R.D.

1998-01-01

This document establishes performance requirements for the double-shell tank system. These requirements, in turn, will be incorporated in the System Specification for the Double-Shell Tank System (Grenard and Claghorn 1998). This version of the document establishes requirements that are applicable to the first phase (Phase 1) of the Tank Waste Remediation System (TWRS) mission described in the TWRS Mission Analysis Report (Acree 1998). It does not specify requirements for either the Phase 2 mission or the double-shell tank system closure period

Spastic pelvic floor syndrome: Definition in double-exposure defaecography

International Nuclear Information System (INIS)

Helzel, M.V.

1989-01-01

Double-exposure defaecography and the so-called pinching test improve conventional defaecography in the diagnosis of functional rectal outlet disorders. In particular, the pinching test makes quantitative evaluation of the m. puborectalis possible. 'Spastic pelvic floor syndrome' is defined by quantitative parameters in double-exposure defaecography and the pinching test. (orig.) [de

Double burden of disease in the slums of Kenya

NARCIS (Netherlands)

Oti, S.O.

2015-01-01

The goal of this thesis was to provide evidence of a double burden of disease in the slums of Nairobi and to make a case for an integrated health systems approach to tackling this situation. A double burden of disease refers to the coexistence of a high burden of communicable and non-communicable

Fragmentation in DNA double-strand breaks

International Nuclear Information System (INIS)

Wei Zhiyong; Suzhou Univ., Suzhou; Zhang Lihui; Li Ming; Fan Wo; Xu Yujie

2005-01-01

DNA double strand breaks are important lesions induced by irradiations. Random breakage model or quantification supported by this concept is suitable to analyze DNA double strand break data induced by low LET radiation, but deviation from random breakage model is more evident in high LET radiation data analysis. In this work we develop a new method, statistical fragmentation model, to analyze the fragmentation process of DNA double strand breaks. After charged particles enter the biological cell, they produce ionizations along their tracks, and transfer their energies to the cells and break the cellular DNA strands into fragments. The probable distribution of the fragments is obtained under the condition in which the entropy is maximum. Under the approximation E≅E 0 + E 1 l + E 2 l 2 , the distribution functions are obtained as exp(αl + βl 2 ). There are two components, the one proportional to exp(βl 2 ), mainly contributes to the low mass fragment yields, the other component, proportional to exp(αl), decreases slowly as the mass of the fragments increases. Numerical solution of the constraint equations provides parameters α and β. Experimental data, especially when the energy deposition is higher, support the statistical fragmentation model. (authors)

Retrieval of proximally migrated double J ureteric stents in children using goose neck snare

Directory of Open Access Journals (Sweden)

Sivasankar Jayakumar

2012-01-01

Full Text Available Purpose: Proximal migration of the ureteric double J stent is a rare but known complication. We describe three cases where a minimally invasive technique for retrieval of displaced double J stents using Amplatz™ goose-neck snare was successful. Materials and Methods: A retrospective review of patients with displaced double J stent was carried out, in whom cystoscopy guided retrieval of double J stent was attempted with the help of Amplatz goose-neck snare under radiological control. Results: All three patients were under the age of 3 years. Two patients had migrated double J stent following pyeloplasty and in one patient the double J stent was displaced during a retrograde insertion of double J stent. In all cases, retrieval of displaced double J stent was successfully achieved using Amplatz goose-neck snare. There were no postoperative complications. Conclusion: Our method of retrieval of stent from renal pelvis is simple, safe and minimally invasive. This technique is a useful and safe alternative option for retrieval of proximally migrated double J stents in children.

Penatalaksanaan Repair Palatoplasty dengan Teknik Furlow Double Opposing Z Plasty

Directory of Open Access Journals (Sweden)

Pingky Krisna Arindra

2015-06-01

metode Furlow double opposing z plasty dengan kombinasi insisi lateral, dan didapatkan hasil menutupnya celah di palatum mole sampai dengan uvula. Telah dilakukan operasi repair palatoplasi dengan metode Furlow double opposing z plasty. Teknik ini dilakukan untuk menghindari insisi yang terlalu luas dikarenakan terdapatnya jaringan fibrous yang tebal pada mukosa palatum pasca operasi sebelumnya. Tujuan studi kasus adalah untuk mengetahui kemampuan teknik Furlow Double Opposing Z Plasty sebagai prosedur repair palatoplasty.   Repair Palatoplasty Management with Furlow Double Opposing Z Plasty Technique. Cases of cleft lip and palate are one of the deformity disorders that often occur. There are variety of clinical appearance ranging from incomplete to complete cases. Clinical appearance with different width requires proper surgical technique. Patients with cleft lip and palate had undergone surgical intervention, so that they needed surgical correction to repair the result or failure of the previous surgery. A Four year old boy complain there was cleft on the soft palate. The patient was diagnosed with labiognatopalatoscisis. The patient had undergone two stages of cleft lip surgery and twice of cleft palate surgery with pushback method and repair with z plasty, however the result was unsatisfactory. Further, the patient underwent repair palatoplasty surgery with Furlow double opposing z plasty method combined with lateral relaxing insicion. The result in the post surgery was the closure of cleft soft palate up to uvula. Repair palataplasty surgery has been done with Furlow double opposing z plasty method. This technique could avoid extended incision due to thick fibrous tissue on the palatum mucosa as the result of serial previous surgery. The aim of this case case study is to determine the technical capabilities of Furlow Double Opposing Z Plasty as palatoplasty repair procedure.

Simple and double two-colour photoionization of rare gas atoms

International Nuclear Information System (INIS)

Guyetand, O.

2008-05-01

The present work deals with simple and double ionization of rare gases by harmonic radiation produced by, and combined with, an intense femtosecond infrared laser. Technical aspects related to the use of harmonic generation and to the detection of ions and electrons in coincidence are exposed. Theoretical background for two colour, few-photon, single and double ionization is detailed. Spectra and angular distributions of the photoelectrons measured in helium are described and compared with TDSE (time-dependent Schroedinger equation) theoretical calculations, for various conditions of the harmonic photons. The shape of the angular distributions can be explained within the frame of two distinct analytic approaches: the perturbation theory and the soft-photon approximation. The double ionization measurements have been performed on xenon, a complex atom characterized by many possible routes leading to double ionization. The analysis of energy and angular correlations of the two photoelectrons proves the feasibility of such experiments that combines harmonic and infrared radiations. It shows that two step processes are dominant in the case of xenon. This work appeals for extending few-photon, double ionization experiments to lighter rare gases. (author)

Double standards with radioactive waste

International Nuclear Information System (INIS)

Parkinson, A.

2002-01-01

The author claims that whether it is short-lived waste from Commonwealth facilities, long-lived plutonium waste from an atomic bomb test site on Aboriginal land, or reactor waste from Lucas Heights, the Australian government applies double standards to suit its own agenda

Bias stress instability of double-gate a-IGZO TFTs on polyimide substrate

Science.gov (United States)

Cho, Won-Ju; Ahn, Min-Ju

2017-09-01

In this study, flexible double-gate thin-film transistor (TFT)-based amorphous indium-galliumzinc- oxide (a-IGZO) was fabricated on a polyimide substrate. Double-gate operation with connected front and back gates was compared with a single-gate operation. As a result, the double-gate a- IGZO TFT exhibited enhanced electrical characteristics as well as improved long-term reliability. Under positive- and negative-bias temperature stress, the threshold voltage shift of the double-gate operation was much smaller than that of the single-gate operation.

Electron-helium S-wave model benchmark calculations. II. Double ionization, single ionization with excitation, and double excitation

Science.gov (United States)

Bartlett, Philip L.; Stelbovics, Andris T.

2010-02-01

The propagating exterior complex scaling (PECS) method is extended to all four-body processes in electron impact on helium in an S-wave model. Total and energy-differential cross sections are presented with benchmark accuracy for double ionization, single ionization with excitation, and double excitation (to autoionizing states) for incident-electron energies from threshold to 500 eV. While the PECS three-body cross sections for this model given in the preceding article [Phys. Rev. A 81, 022715 (2010)] are in good agreement with other methods, there are considerable discrepancies for these four-body processes. With this model we demonstrate the suitability of the PECS method for the complete solution of the electron-helium system.

Improving Breakdown Behavior by Substrate Bias in a Novel Double Epi-layer Lateral Double Diffused MOS Transistor

International Nuclear Information System (INIS)

Li Qi; Wang Wei-Dong; Liu Yun; Wei Xue-Ming

2012-01-01

A new lateral double diffused MOS (LDMOS) transistor with a double epitaxial layer formed by an n-type substrate and a p-type epitaxial layer is reported (DEL LDMOS). The mechanism of the improved breakdown characteristic is that the high electric field around the drain is reduced by substrate reverse bias, which causes the redistribution of the bulk electric field in the drift region, and the vertical blocking voltage is shared by the drain side and the source side. The numerical results indicate that the trade-off between breakdown voltage and on-resistance of the proposed device is improved greatly in comparison to that of the conventional LDMOS. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

Quantum Phase Spase Representation for Double Well Potential

OpenAIRE

Babyuk, Dmytro

2002-01-01

A behavior of quantum states (superposition of two lowest eigenstates, Gaussian wave packet) in phase space is studied for one and two dimensional double well potential. Two dimensional potential is constructed from double well potential coupled linearly and quadratically to harmonic potential. Quantum trajectories are compared with classical ones. Preferable tunneling path in phase space is found. An influence of energy of initial Gaussian wave packet and trajectory initial condition on tunn...

On the nuclear double beta decay: microscopic description

International Nuclear Information System (INIS)

Civitarese, Osvaldo

1989-01-01

This paper is devoted to the discussion of some problems related with microscopic descriptions of the nuclear double beta decay. It has been organized in the following order: 1) Review of the experimental situation; 2) Brief discussion of the theoretical aspects related to the current algebra, weak interaction, neutrino and majoron's status and 3) Elements of the standard nuclear theory involved in the calculation of transition densities for the nuclear double beta decay. (Author) [es

Double Taxation Conventions in Central and Eastern European Countries

Directory of Open Access Journals (Sweden)

Dumiter Florin

2016-12-01

Full Text Available In this article we provide a qualitative overview regarding the panacea of double taxation conventions in Central and Eastern European Countries. Double taxation paradigm highlights some serious problems arising from multiple taxation of the same income or capital. In the European Union these problems suggest that there is a strong need of a “best practice” construction of an optimal fiscal space in order to eliminate or reduce this problem. Central and Eastern European Countries have some special features: on one hand these countries have been influenced by the communist and postcommunism era, and on the other hand there are specific particularities for each country which must be economically and judicially understood and explained. This article highlights the structure, construction and appliance of the double taxation conventions in the Central and Eastern European Countries. The conclusions of this article enact the solutions of the potential problems of double taxation, especially in these former communist countries, with respect to the strengthening of the new fiscal space in the European Union.

Rate Theory for Correlated Processes: Double Jumps in Adatom Diffusion

DEFF Research Database (Denmark)

Jacobsen, J.; Jacobsen, Karsten Wedel; Sethna, J.

1997-01-01

We study the rate of activated motion over multiple barriers, in particular the correlated double jump of an adatom diffusing on a missing-row reconstructed platinum (110) surface. We develop a transition path theory, showing that the activation energy is given by the minimum-energy trajectory...... which succeeds in the double jump. We explicitly calculate this trajectory within an effective-medium molecular dynamics simulation. A cusp in the acceptance region leads to a root T prefactor for the activated rate of double jumps. Theory and numerical results agree....

Surface residual stress evaluation in double-electrode butt welded steel plates

International Nuclear Information System (INIS)

Estefen, S.F.; Gurova, T.; Castello, X.; Leontiev, A.

2010-01-01

Surface residual stress evaluation for double-electrode welding was studied. The stresses were monitored after each operational step: positioning, implementing of constraints, welding and constraints removal. The measurements were performed at the deposited metal, heat affected zone, base metal close to the weld joint and along the plate using the X-ray diffraction method. It was observed differences in the stress evaluations for double-electrode welding which resulted in lower bending distortions and higher values of surface residual stresses, compared with single-electrode welding. This behavior is associated with the stress distribution just after the welding processes in both heat affected zone and base metal close to the fillet for double-electrode welding. The main results from the laboratorial tests indicated lower values of the bending distortions for double-electrode welding compared with the single-electrode. In relation to the residual stress, the double-electrode welding generated, in general, higher stress values in both longitudinal and transversal directions.

Search for new physics with neutrinoless double beta decay

International Nuclear Information System (INIS)

Klapdor-Kleingrothaus, H.V.; Baudis, L.; Hellmig, J.; Hirsch, M.; Kolb, S.; Paes, H.; Ramachers, Y.

1999-01-01

Neutrinoless double beta decay (0νββ) is one of the most sensitive approaches to test particle physics beyond the standard model. During the last years, besides the most restrictive limit on the effective Majorana neutrino mass, the analysis of new contributions by the Heidelberg group led to bounds on left-right-symmetric models, leptoquarks and R-parity violating models competitive to recent accelerator limits, which are of special interest in view of the HERA anomaly at large Q 2 and x. These new results deduced from the Heidelberg-Moscow double beta decay experiment are reviewed. Also an outlook on the future of double beta decay, the GENIUS proposal, is given

Comparative evaluation of positive contrast and double contrast gastrography in dogs

International Nuclear Information System (INIS)

Dileepkumar, K.M.; Rajankutty, K.; Sarada, Amma T.; Devanand, C.B.; Vijayan, N.

2012-01-01

A contrast radiography of stomach with oral barium sulphate suspension 25% (5 mL/kg b.wt positive contrast) and double contrast with oral barium sulphate 25% (3 mL/kg b.wt) followed by air (2 to 10 mL/kg b.wt, negative contrast) was done on six dogs to study the affections of stomach. Contrast radiography using barium sulphate alone was found satisfactory to identify most of the lesions of the stomach. Double contrast radiography using barium sulphate and air, required sedation to control the animals for proper administration. For the diagnosis of mucosal lesions, double contrast radiography was better than barium sulphate alone. Key words: Barium, Contrast radiography, Dog, Double contrast, Stomach

Double-tuned radiofrequency coil for (19)F and (1)H imaging.

Science.gov (United States)

Otake, Yosuke; Soutome, Yoshihisa; Hirata, Koji; Ochi, Hisaaki; Bito, Yoshitaka

2014-01-01

We developed a double-tuned radiofrequency (RF) coil using a novel circuit method to double tune for fluorine-19 (19F) and 1H magnetic resonance imaging, whose frequencies are very close to each other. The RF coil consists of 3 parallel-connected series inductor capacitor circuits. A computer simulation for our double-tuned RF coil with a phantom demonstrated that the coil has tuned resonant frequency and high sensitivity for both 19F and 1H. Drug distribution was visualized at 7 tesla using this RF coil and a rat administered perfluoro 15-crown-5-ether emulsion. The double-tune RF coil we developed may be a powerful tool for 19F and 1H imaging.

How universal is the period doubling phenomenon in equations with quadratic nonlinearity

International Nuclear Information System (INIS)

Malta, C.P.; Oliveira, C.R. de.

1983-09-01

Varying one parameter, the solution of nonlinear 1 sup(st) order differential equation with time delay tau is Fourier analysed. After the Hopf bifurcation, period-doubling phenomenon always occurs when tau is one of the fixed parameters (both for small and large tau). Varying tau, there are values of the fixed parameters for which no period-doubling occurs. 'Chaos' follows the period-doubling sequence and the rate at which 'chaos' is approached is very close to the universal delta = 4.6692016... characterising the period-doubling sequence to chaos in nonlinear difference equations. (Author) [pt

Method for double-sided processing of thin film transistors

Science.gov (United States)

Yuan, Hao-Chih; Wang, Guogong; Eriksson, Mark A.; Evans, Paul G.; Lagally, Max G.; Ma, Zhenqiang

2008-04-08

This invention provides methods for fabricating thin film electronic devices with both front- and backside processing capabilities. Using these methods, high temperature processing steps may be carried out during both frontside and backside processing. The methods are well-suited for fabricating back-gate and double-gate field effect transistors, double-sided bipolar transistors and 3D integrated circuits.

The Commission's proposal for a Directive on Double Taxation Dispute Resolution Mechanisms:Overcoming the final hurdle of juridical double taxation within the European Union?

OpenAIRE

Cerioni, Luca

2017-01-01

This article examines the Commission’s proposal for a Directive on Double Taxation Dispute Resolution Mechanisms, by highlighting interpretative issues that its wording may arise and by discussing the conditions under which it could manage to lead to the elimination of (juridical) double taxation within the EU.

Double-Row Capsulolabral Repair Increases Load to Failure and Decreases Excessive Motion.

Science.gov (United States)

McDonald, Lucas S; Thompson, Matthew; Altchek, David W; McGarry, Michelle H; Lee, Thay Q; Rocchi, Vanna J; Dines, Joshua S

2016-11-01

Using a cadaver shoulder instability model and load-testing device, we compared biomechanical characteristics of double-row and single-row capsulolabral repairs. We hypothesized a greater reduction in glenohumeral motion and translation and a higher load to failure in a mattress double-row capsulolabral repair than in a single-row repair. In 6 matched pairs of cadaveric shoulders, a capsulolabral injury was created. One shoulder was repaired with a single-row technique, and the other with a double-row mattress technique. Rotational range of motion, anterior-inferior translation, and humeral head kinematics were measured. Load-to-failure testing measured stiffness, yield load, deformation at yield load, energy absorbed at yield load, load to failure, deformation at ultimate load, and energy absorbed at ultimate load. Double-row repair significantly decreased external rotation and total range of motion compared with single-row repair. Both repairs decreased anterior-inferior translation compared with the capsulolabral-injured condition, however, no differences existed between repair types. Yield load in the single-row group was 171.3 ± 110.1 N, and in the double-row group it was 216.1 ± 83.1 N (P = .02). Ultimate load to failure in the single-row group was 224.5 ± 121.0 N, and in the double-row group it was 373.9 ± 172.0 N (P = .05). Energy absorbed at ultimate load in the single-row group was 1,745.4 ± 1,462.9 N-mm, and in the double-row group it was 4,649.8 ± 1,930.8 N-mm (P = .02). In cases of capsulolabral disruption, double-row repair techniques may result in decreased shoulder rotational range of motion and improved load-to-failure characteristics. In cases of capsulolabral disruption, repair techniques with double-row mattress repair may provide more secure fixation. Double-row capsulolabral repair decreases shoulder motion and increases load to failure, yield load, and energy absorbed at yield load more than single-row repair. Published by

Evaluation of double-decker traps for emerald ash borer (Coleoptera: Buprestidae).

Science.gov (United States)

Poland, Therese M; McCullough, Deborah G; Anulewicz, Andrea C

2011-04-01

Improved detection tools are needed for the emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), an invasive forest insect from Asia that has killed millions of ash (Fraxinus spp.) trees in North America since its discovery in Michigan in 2002. We evaluated attraction of adult A. planipennis to artificial traps incorporating visual (e.g., height, color, silhouette) and olfactory cues (e.g., host volatiles) at field sites in Michigan. We developed a double-decker trap consisting of a 3-m-tall polyvinyl pipe with two purple prisms attached near the top. In 2006, we compared A. planipennis attraction to double-decker traps baited with various combinations of manuka oil (containing sesquiterpenes present in ash bark), a blend of four ash leaf volatiles (leaf blend), and a rough texture to simulate bark. Significantly more A. planipennis were captured per trap when traps without the rough texture were baited with the leaf blend and manuka oil lures than on traps with texture and manuka oil but no leaf blend. In 2007, we also tested single prism traps set 1.5 m above ground and tower traps, similar to double-decker traps but 6 m tall. Double-decker traps baited with the leaf blend and manuka oil, with or without the addition of ash leaf and bark extracts, captured significantly more A. planipennis than similarly baited single prism traps, tower traps, or unbaited double-decker traps. A baited double-decker trap captured A. planipennis at a field site that was not previously known to be infested, representing the first detection event using artificial traps and lures. In 2008, we compared purple or green double-decker traps, single prisms suspended 3-5 m above ground in the ash canopy (canopy traps), and large flat purple traps (billboard traps). Significantly more A. planipennis were captured in purple versus green traps, baited traps versus unbaited traps, and double-decker versus canopy traps, whereas billboard traps were intermediate. At sites

The double copy: gravity from gluons

Science.gov (United States)

White, C. D.

2018-04-01

Three of the four fundamental forces in nature are described by so-called gauge theories, which include the effects of both relativity and quantum mechanics. Gravity, on the other hand, is described by General Relativity, and the lack of a well-behaved quantum theory - believed to be relevant at the centre of black holes, and at the Big Bang itself - remains a notorious unsolved problem. Recently a new correspondence, the double copy, has been discovered between scattering amplitudes (quantities related to the probability for particles to interact) in gravity, and their gauge theory counterparts. This has subsequently been extended to other quantities, providing gauge theory analogues of e.g. black holes. We here review current research on the double copy, and describe some possible applications.

Dividends Provisions in Croatian Double Taxation Agreements

Directory of Open Access Journals (Sweden)

Marjeta Tomulić Vehovec

2007-03-01

Full Text Available This paper analyzes the provisions concerning dividends in the double taxation avoidance agreements concluded by the Republic of Croatia. Since the base for taxation is necessarily laid down in domestic law, Croatian legislation is examined as well. The author primarily discusses dividends provisions in four agreements signed with Germany, Austria, Switzerland and Slovenia, in addition to analyzing the differences from and similarities with the OECD Model Convention. Second, the paper briefly explains the methods for eliminating double taxation on income from dividends. Finally, it addresses the changes necessary for accession to the European Union.

Large magnetocurrents in double-barrier tunneling transistors

International Nuclear Information System (INIS)

Lee, J.H.; Jun, K.-I.; Shin, K.-H.; Park, S.Y.; Hong, J.K.; Rhie, K.; Lee, B.C.

2005-01-01

Magnetic tunneling transistors (MTT) with double tunneling barriers are fabricated. The structure of the transistor is AFM/FM/I/FM/I/FM/AFM, and ferromagnetic layers serve as the emitter, base and collector. This double-barrier tunneling transistor (DBTT) has an advantage of controlling the potential between the base and collector, compared to the Schottky-barrier-based base and collector of MTT. We found that the collector current density of DBTT is at least 10 3 times larger than that of conventional MTT, since tunneling through AlO x barrier provides much larger current density than that through Schottky barrier

How bright planets became dim stars: planetary speculations in John Herschel's double star astronomy.

Science.gov (United States)

Case, Stephen

2014-03-01

Previous research on the origins of double star astronomy in the early nineteenth century emphasized the role mathematical methods and instrumentation played in motivating early observations of these objects. The work of the British astronomer John Herschel, however, shows that questions regarding the physical nature of double stars were also important. In particular, an analysis of John Herschel's early work on double stars illustrates the way in which speculations regarding these objects were shaped by assumptions of the properties of stars themselves. For Herschel, a major consideration in double star astronomy was distinguishing between types of double stars. Optical doubles were useful in determining parallax while binary doubles were not. In practice, classification of a specific double star pair into one of these categories was based on the assumption that stars were of approximately the same luminosity and thus differences in relative brightness between stars were caused by difference in distances. Such assumptions, though ultimately abandoned, would lead Herschel in the 1830s to advance the possibility that the dim companion stars in certain double star pairs were not stars at all but in fact planets. Copyright © 2014 Elsevier Ltd. All rights reserved.

Functional Analysis for Double Shell Tank (DST) Subsystems

International Nuclear Information System (INIS)

SMITH, D.F.

2000-01-01

This functional analysis identifies the hierarchy and describes the subsystem functions that support the Double-Shell Tank (DST) System described in HNF-SD-WM-TRD-007, System Specification for the Double-Shell Tank System. Because of the uncertainty associated with the need for upgrades of the existing catch tanks supporting the Waste Feed Delivery (WFD) mission, catch tank functions are not addressed in this document. The functions identified herein are applicable to the Phase 1 WFD mission only

Vortex dynamics mediated by exchange coupling in permalloy double disks

International Nuclear Information System (INIS)

Liu Yan; Hu Yong; Du An

2012-01-01

The dynamics of magnetic vortices in double disks coupled with a bridge are studied by micromagnetic simulations. There are three types of magnetic configurations being found, which depend on the size of the bridge and the chiralities of the vortices. The exchange coupling between the vortices, which is mediated by the magnetizations in the bridge, influences the trajectories and oscillation frequencies of the vortices. Moreover, the frequency depends on the configurations of the double disks and the bridge size. - Highlights: ► Dynamics of vortices in double Permalloy disks coupled with a bridge are studied. ► Three types of equilibrium configurations are observed for the model. ► Oscillation of the cores depends on the magnetic configuration of the double disks. ► Variation of oscillating frequency with bridge length depends on polarity combination. ► Oscillating frequency decreases with the increasing of the bridge width.

Effect of double-layer application on bond quality of adhesive systems.

Science.gov (United States)

Fujiwara, Satoshi; Takamizawa, Toshiki; Barkmeier, Wayne W; Tsujimoto, Akimasa; Imai, Arisa; Watanabe, Hidehiko; Erickson, Robert L; Latta, Mark A; Nakatsuka, Toshiyuki; Miyazaki, Masashi

2018-01-01

The aim of this study was to determine the effect of double-layer application of universal adhesives on the bond quality and compare to other adhesive systems. Two universal adhesives used were in this study: Scotchbond Universal (SU), [3M ESPE] and Prime & Bond elect (PE), [Dentsply Caulk]. The conventional single-step self-etch adhesives G-ӕnial Bond (GB), [GC Corporation.] and BeautiBond (BB), [Shofu Inc.], and a two-step self-etch adhesive, Optibond XTR (OX), [Kerr Corporation], were used as comparison adhesives. Shear bond strengths (SBS) and shear fatigue strengths (SFS) to human enamel and dentin were measured in single application mode and double application mode. For each test condition, 15 specimens were prepared for SBS testing and 30 specimens for SFS testing. Enamel and dentin SBS of the universal adhesives in the double application mode were significantly higher than those of the single application mode. In addition, the universal adhesives in the double application mode had significantly higher dentin SFS values than those of the single application mode. The two-step self-etch adhesive OX tended to have lower bond strengths in the double application mode, regardless of the test method or adherent substrate. The double application mode is effective in enhancing SBS and SFS of universal adhesives, but not conventional two-step self-etch adhesives. These results suggest that, although the double application mode may enhance the bonding quality of a universal adhesive, it may be counter-productive for two-step self-etch adhesives in clinical use. Copyright © 2017 Elsevier Ltd. All rights reserved.