555 research outputs found
Early evolution of electron cyclotron driven current during suppression of tearing modes in a circular tokamak
When electron cyclotron (EC) driven current is first applied to the inside of
a magnetic island, the current spreads throughout the island and after a short
period achieves a steady level. Using a two equation fluid model for the EC
current that allows us to examine this early evolution in detail, we analyze
high-resolution simulations of a 2/1 classical tearing mode in a low-beta large
aspect-ratio circular tokamak. These simulations use a nonlinear 3D reduced-MHD
fluid model and the JOREK code. During the initial period where the EC driven
current grows and spreads throughout the magnetic island, it is not a function
of the magnetic flux. However, once it has reached a steady-state, it should be
a flux function. We demonstrate numerically that if sufficiently resolved
toroidally, the steady-state EC driven current becomes approximately a flux
function. We discuss the physics of this early period of EC evolution and its
impact on the size of the magnetic island.Comment: 12 pages, 7 figure
Understanding the effect resonant magnetic perturbations have on ELMs
All current estimations of the energy released by type I ELMs indicate that,
in order to ensure an adequate lifetime of the divertor targets on ITER, a
mechanism is required to decrease the amount of energy released by an ELM, or
to eliminate ELMs altogether. One such amelioration mechanism relies on
perturbing the magnetic field in the edge plasma region, either leading to more
frequent, smaller ELMs (ELM mitigation) or ELM suppression. This technique of
Resonant Magnetic Perturbations (RMPs) has been employed to suppress type I
ELMs at high collisionality/density on DIII-D, ASDEX Upgrade, KSTAR and JET and
at low collisionality on DIII-D. At ITER-like collisionality the RMPs enhance
the transport of particles or energy and keep the edge pressure gradient below
the 2D linear ideal MHD critical value that would trigger an ELM, whereas at
high collisionality/density the type I ELMs are replaced by small type II ELMs.
Although ELM suppression only occurs within limitied operational ranges, ELM
mitigation is much more easily achieved. The exact parameters that determine
the onset of ELM suppression are unknown but in all cases the magnetic
perturbations produce 3D distortions to the plasma and enhanced particle
transport. The incorporation of these 3D effects in codes will be essential in
order to make quantitative predictions for future devices.Comment: 32 pages, 9 figure
HPV Prevalence in the Dutch cervical cancer screening population (DuSC study): HPV testing using automated HC2, cobas and Aptima workflows
Generationing development
The articles in this special issue present a persuasive case for accounts of development to recognise the integral and fundamental roles played by age and generation. While the past two decades have witnessed a burgeoning of literature demonstrating that children and youth are impacted by development, and that they can and do participate in development, the literature has tended to portray young people as a special group whose perspectives should not be forgotten. By contrast, the articles collected here make the case that age and generation, as relational constructs, cannot be ignored. Appropriating the term ‘generationing’, the editors argue that a variety of types of age relations profoundly structure the ways in which societies are transformed through development – both immanent processes of neoliberal modernisation and the interventions of development agencies that both respond and contribute to these. Drawing on the seven empirical articles, I attempt to draw some of the ideas together into a narrative that further argues the case for ‘generationing’ but also identifies gaps, questions and implications for further research
Single Nucleotide Polymorphism (SNP)-Based Loss of Heterozygosity (LOH) Testing by Real Time PCR in Patients Suspect of Myeloproliferative Disease
During tumor development, loss of heterozygosity (LOH) often occurs. When LOH is preceded by an oncogene activating mutation, the mutant allele may be further potentiated if the wild-type allele is lost or inactivated. In myeloproliferative neoplasms (MPN) somatic acquisition of JAK2V617F may be followed by LOH resulting in loss of the wild type allele. The occurrence of LOH in MPN and other proliferative diseases may lead to a further potentiating the mutant allele and thereby increasing morbidity. A real time PCR based SNP profiling assay was developed and validated for LOH detection of the JAK2 region (JAK2LOH). Blood of a cohort of 12 JAK2V617F-positive patients (n = 6 25–50% and n = 6>50% JAK2V617F) and a cohort of 81 patients suspected of MPN was stored with EDTA and subsequently used for validation. To generate germ-line profiles, non-neoplastic formalin-fixed paraffin-embedded tissue from each patient was analyzed. Results of the SNP assay were compared to those of an established Short Tandem Repeat (STR) assay. Both assays revealed JAK2LOH in 1/6 patients with 25–50% JAK2V617F. In patients with >50% JAK2V617F, JAK2LOH was detected in 6/6 by the SNP assay and 5/6 patients by the STR assay. Of the 81 patients suspected of MPN, 18 patients carried JAK2V617F. Both the SNP and STR assay demonstrated the occurrence of JAK2LOH in 5 of them. In the 63 JAK2V617F-negative patients, no JAK2LOH was observed by SNP and STR analyses. The presented SNP assay reliably detects JAK2LOH and is a fast and easy to perform alternative for STR analyses. We therefore anticipate the SNP approach as a proof of principle for the development of LOH SNP-assays for other clinically relevant LOH loci
Theorising age and generation in development: A relational approach
This introduction outlines the analytical approach informing the articles presented in this special issue. The project of ‘generationing’ development involves re-thinking development as distinctly generational in its dynamics. For this, we adopt a relational approach to the study of young people in development, which overcomes the limitations inherent to common categorising approaches. Concepts of age and generation are employed to conceptualise young people as social actors and life phases such as childhood and youth in relational terms. Acknowledging the centrality of young people in social reproduction puts them at the heart of development studies and leads the articles comprising this special issue to explore how young people’s agency shapes and is shaped by the changing terms of social reproduction brought about by development
PAS Update aanvullende reservemaatregelen Landbouw
In many Natura 2000 area’s, the nitrogen deposition is higher than wished for. This led to a deadlock in economic development of,among others,livestock husbandry. For the three sector groups Traffic and Transportation, Industry and Energy, and Agriculture source measures were listedin 2017 to deal with the bottlenecks. For agriculture, the list with measures is updated in consultation with representatives of the agricultural sector, research and policy, developed and written in this present report. This study was performed by order of the Ministry of Agriculture, Nature and Food qualitybefore the Council of State made judgement regarding PAS
Early evolution of electron cyclotron driven current during suppression of tearing modes in a circular tokamak
PAS Aanvullende reservemaatregelen Landbouw: uitwerking van een quick scan
In many Natura 2000 area’s, the nitrogen deposition is higher than wished for. This led to a deadlock in economic development of, among others, livestock husbandry. The interdepartmental program ‘Programma Aanpak Stikstof’ (PAS), is meant to overcome the standstill of grants of permits to produce, while in term preservation goals of nature area’s can be achieved. For the three sector groups Traffic and Transportation, Industry and Energy, and Agriculture source measures are inventoried to deal with the bottlenecks. By order of the Ministry of Economic Affairs this report presents the inventory of measures for agriculture
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