199 research outputs found
Strategien zur Reduktion der CT-Strahlendosis
Zusammenfassung: Die rasante technische Weiterentwicklung der CT hat in den letzten Jahren zu einer deutlichen Zunahme der diagnostischen Möglichkeiten gefĂŒhrt, mit dem Resultat, dass die CT-Untersuchungszahlen weltweit angestiegen sind. Dies hat ebenfalls Auswirkung auf die Strahlenexposition der Bevölkerung. Bis heute sind zahlreiche Publikationen erschienen, die gezeigt haben, dass eine Dosisreduktion erreicht werden kann, ohne dadurch die BildqualitĂ€t und SensitivitĂ€t der CT zu beeintrĂ€chtigen. Die Mehrzahl der Strategien zur Dosisoptimierung sind einfach anzuwenden und unabhĂ€ngig von der Detektorkonfiguration des CT-Scanners. Im vorliegenden Ăbersichtsartikel werden die wichtigsten Methoden vorgestellt: indikationsabhĂ€ngige Methoden (z.B. rechtfertigende Indikation, Reduktion der Röhrenspannung fĂŒr die CT-Angiographie, Wahl von Kollimation und Pitchfaktor, Minimierung der Untersuchungsphasen, Senkung der Röhrenspannung und des -stroms fĂŒr die Nativphase), herstellerabhĂ€ngige Methoden (z.B. automatische Röhrenstrommodulation, adaptive Filter zur Reduktion des Bildrauschens, iterative Bildrekonstruktion) und allgemeine Methoden (z.B. Patientenzentrierung im Isozentrum der CT-Gantry, Reduktion der ScanlĂ€nge, Anwendung von Röntgenschutzmitteln, Reduktion der Röhrenspannung und/oder des -stroms fĂŒr den CT-Planungsscan
New England Wind Energy Education Project (NEWEEP)
Project objective is to develop and disseminate accurate, objective information on critical wind energy issues impacting market acceptance of hundreds of land-based projects and vast off-shore wind developments proposed in the 6-state New England region, thereby accelerating the pace of wind installation from today's 140 MW towards the region's 20% by 2030 goals of 12,500 MW. Methodology: This objective will be accomplished by accumulating, developing, assembling timely, accurate, objective and detailed information representing the 'state of the knowledge' on critical wind energy issues impacting market acceptance, and widely disseminating such information. The target audience includes state agencies and local governments; utilities and grid operators; wind developers; agricultural and environmental groups and other NGOs; research organizations; host communities and the general public, particularly those in communities with planned or operating wind projects. Information will be disseminated through: (a) a series of topic-specific web conference briefings; (b) a one-day NEWEEP conference, back-to-back with a Utility Wind Interest Group one-day regional conference organized for this project; (c) posting briefing and conference materials on the New England Wind Forum (NEWF) web site and featuring the content on NEWF electronic newsletters distributed to an opt-in list of currently over 5000 individuals; (d) through interaction with and participation in Wind Powering America (WPA) state Wind Working Group meetings and WPA's annual All-States Summit, and (e) through the networks of project collaborators. Sustainable Energy Advantage, LLC (lead) and the National Renewable Energy Laboratory will staff the project, directed by an independent Steering Committee composed of a collaborative regional and national network of organizations. Major Participants - the Steering Committee: In addition to the applicants, the initial collaborators committing to form a Steering Committee consists of the Massachusetts Renewable Energy Trust; Maine Public Utilities Commission; New Hampshire office of Energy & Planning, the Connecticut Clean Energy Fund;, ISO New England; Utility Wind Interest Group; University of Massachusetts Wind Energy Center; Renewable Energy New England (a new partnership between the renewable energy industry and environmental public interest groups), and Lawrence Berkeley National Laboratory (conditionally). The Steering Committee will: (1) identify and prioritize topics of greatest interest or concern where detailed, objective and accurate information will advance the dialogue in the region; (2) identify critical outreach venues, influencers and experts; (3) direct and coordinate project staff; (4) assist project staff in planning briefings and conferences described below; (5) identify topics needing additional research or technical assistance and (6) identify and recruit additional steering committee members. Impacts/Benefits/Outcomes: By cutting through the clutter of competing and conflicting information on critical issues, this project is intended to encourage the market's acceptance of appropriately-sited wind energy generation
Equal pay by gender and by nationality: a comparative analysis of Switzerland's unequal equal pay policy regimes across time
What explains the adoption of two different policies on equal pay by gender (EPG) and by nationality (EPN) in Switzerland? And why is the liberal, litigation-based, equal pay policy regime set up by the Gender Equality Act of 1996 much less effective than the neocorporatist âaccompanying measures' to the Bilateral European Union-Switzerland Agreement on Free Movement of Persons adopted in 1999 to ensure equal pay for workers of different national origins? The formation of two different policy regimes cannot be explained by different levels of political will. Equally, different âvarieties of capitalism' cannot explain the setup of the two different equal pay policy regimes within the very same country. Instead, our qualitative comparative analysis across time suggests that the differences can be best explained by a particular constellation of attributes, namely the use of different policy framesâi.e. âanti-discrimination' in the EPG and âunfair competition' in the EPN caseâand the different setting of interest politics epitomised by the opposite stances adopted by Switzerland's employer associations in the two case
Infants with esophageal atresia and right aortic arch: Characteristics and outcomes from the Midwest Pediatric Surgery Consortium
Purpose
Right sided aortic arch (RAA) is a rare anatomic finding in infants with esophageal atresia with or without tracheoesophageal fistula (EA/TEF). In the presence of RAA, significant controversy exists regarding optimal side for thoracotomy in repair of the EA/TEF. The purpose of this study was to characterize the incidence, demographics, surgical approach, and outcomes of patients with RAA and EA/TEF.
Methods
A multi-institutional, IRB approved, retrospective cohort study of infants with EA/TEF treated at 11 children's hospitals in the United States over a 5-year period (2009 to 2014) was performed. All patients had a minimum of one-year follow-up.
Results
In a cohort of 396 infants with esophageal atresia, 20 (5%) had RAA, with 18 having EA with a distal TEF and 2 with pure EA. Compared to infants with left sided arch (LAA), RAA infants had a lower median birth weight, (1.96âŻkg (IQR 1.54â2.65) vs. 2.57âŻkg (2.00â3.03), pâŻ=âŻ0.01), earlier gestational age (34.5âŻweeks (IQR 32â37) vs. 37âŻweeks (35â39), pâŻ=âŻ0.01), and a higher incidence of congenital heart disease (90% vs. 32%, pâŻâŻ0.29).
Conclusion
RAA in infants with EA/TEF is rare with an incidence of 5%. Compared to infants with EA/TEF and LAA, infants with EA/TEF and RAA are more severely ill with lower birth weight and higher rates of prematurity and complex congenital heart disease. In neonates with RAA, surgical repair of the EA/TEF is technically feasible via thoracotomy from either chest. A higher incidence of anastomotic strictures may occur with a right-sided approach
Corrigendum to 'Editor's Choice - European Society for Vascular Surgery (ESVS) 2020 Clinical Practice Guidelines on the Management of Vascular Graft and Endograft Infections' [European Journal of Vascular & Endovascular Surgery 59/3 (2020) 339-384]
peer reviewe
Valley splitting in low-density quantum-confined heterostructures studied using tight-binding models
Draft Genome Sequencing of Giardia intestinalis Assemblage B Isolate GS: Is Human Giardiasis Caused by Two Different Species?
Giardia intestinalis is a major cause of diarrheal disease worldwide and two major Giardia genotypes, assemblages A and B, infect humans. The genome of assemblage A parasite WB was recently sequenced, and the structurally compact 11.7 Mbp genome contains simplified basic cellular machineries and metabolism. We here performed 454 sequencing to 16Ă coverage of the assemblage B isolate GS, the only Giardia isolate successfully used to experimentally infect animals and humans. The two genomes show 77% nucleotide and 78% amino-acid identity in protein coding regions. Comparative analysis identified 28 unique GS and 3 unique WB protein coding genes, and the variable surface protein (VSP) repertoires of the two isolates are completely different. The promoters of several enzymes involved in the synthesis of the cyst-wall lack binding sites for encystation-specific transcription factors in GS. Several synteny-breaks were detected and verified. The tetraploid GS genome shows higher levels of overall allelic sequence polymorphism (0.5 versus <0.01% in WB). The genomic differences between WB and GS may explain some of the observed biological and clinical differences between the two isolates, and it suggests that assemblage A and B Giardia can be two different species
The risks of introduction of the Amazonian palm Euterpe oleracea in the Atlantic rainforest
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