Modeling and control of TCV

Published versio

ITER-Earthing

Earthing of electrical installations is mainly governed by safety rules. Electromagnetic compatibility also deals with earthing, among other circuit characteristics. Tokamaks are large-scale electrical installations that are known to generate large and low frequency magnetic fields as well as large and high frequency electric fields. Four European Tokamak installations have been investigated, from the earthing point of view, to identify appropriate techniques to earth the electrical equipment and to provide the lowest possible electromagnetic interference with the measurement circuits. But none of these existing installations looks like ITER, not even remotely. The plasma current range, the superconducting coils, the thick and continuous vacuum vessel, the cryostat, the very high voltage of its neutral beam injectors, the available amount of auxiliary heating power, the sensitivity of its magnetic measurements required for long pulses, the size of the site and the powerful supply grid all affect the plant earthing. Based on these investigations and the ITER specificities, a layout of the ITER site electrical supply grid and of the related earthing grid is proposed. Basic rules to reduce the electromagnetic noise at its sources and to improve the measurement immunity are also suggested

Prototyping a High-Frequency Inductive Magnetic Sensor Using the Nonconventional, Low-Temperature Co-Fired Ceramic Technology for Use in ITER

The ITER high-frequency (HF) magnetic sensor is currently intended to be a conventional, Mirnov-type, pickup coil, designed to provide measurements of magnetic instabilities with magnitude as low as |dB|~10e-4G at the position of the sensors and up to frequencies of at least 300 kHz. Previous prototyping of this sensor has indicated that a number of problems exist with this conventional design that are essentially related to the winding^process and the differential thermal expansion between the metallic wire and the ceramic spacers. Hence, a non-conventional HF magnetic sensor has been designed and prototyped in-house in different variants using low-temperature co-fired ceramic (LTCC) technology, which involves a series of stacked ceramic substrates with a circuit board printed on them with a metallic ink (silver in our case). A method has then been developed to characterize the electrical properties of these sensors from the direct-current range up to frequencies in excess of 10MHz. This method has been successfully benchmarked against the measurements for the built sensors and allows the electrical properties of LTCC prototypes to be predicted with confidence and without the need of actually building them, which therefore significantly simplifies future research and development (R&D) activities. When appropriate design choices are made, LTCC sensors are found to meet in full the volume occupation constraints and the requirements for the sensor's electrical properties that are set out for the ITER HF magnetic diagnostic system. This non-conventional technology is therefore recommended for further R&D and prototyping work, particularly for a three-dimensional sensor, and possibly using materials more suitable for use in the ITER environment, such as palladium and platinum inks, which could remove the perceived risk of transmutation under the heavy neutron flux that we may have with the Au (to Hg, then to Pb) or the Ag (to Cd) metallic inks currently used in LTCC devices

Political Dimensions of Environmental Citizenship

Conceptions of Environmental Citizenship are core to models of sustainability. Such contested conceptions raise historically significant questions associated with the rights of the individual and the responsibility of the community to the environment. Attitudes towards sustainability beg questions of models of citizenship ranging from compliance through democratic deliberation to active dissent. Philosophical problems also intersect with Environmental Citizenship. Ecocentrism prioritises a systemic holistic view of Nature in which the human species has no privileged role. Anthropocentrism in its more liberal aspect has an instrumental view of Nature underpinned by beneficence. These divergent ideologies also presuppose metaphysical and ontological questions about the relationship between Mind and Nature, hence fundamental implications for education and citizenship more broadly. There are, of course, intermediate positions. This raises three driving questions: 1. What are the main philosophical and political positions associated with Environmental Citizenship? 2. What are the justifications underpinning particular approaches to Environmental Citizenship? 3. Can we map the main components of Environmental Citizenship to create a coherent European and Global approach to inquiry

Predicting Impaired Extinction of Traumatic Memory and Elevated Startle

Emotionally traumatic experiences can lead to debilitating anxiety disorders, such as phobias and Post-Traumatic Stress Disorder (PTSD). Exposure to such experiences, however, is not sufficient to induce pathology, as only up to one quarter of people exposed to such events develop PTSD. These statistics, combined with findings that smaller hippocampal size prior to the trauma is associated with higher risk of developing PTSD, suggest that there are pre-disposing factors for such pathology. Because prospective studies in humans are limited and costly, investigating such pre-dispositions, and thus advancing understanding of the genesis of such pathologies, requires the use of animal models where predispositions are identified before the emotional trauma. Most existing animal models are retrospective: they classify subjects as those with or without a PTSD-like phenotype long after experiencing a traumatic event. Attempts to create prospective animal models have been largely unsuccessful.Here we report that individual predispositions to a PTSD-like phenotype, consisting of impaired rate and magnitude of extinction of an emotionally traumatic event coupled with long-lasting elevation of acoustic startle responses, can be revealed following exposure to a mild stressor, but before experiencing emotional trauma. We compare, in rats, the utility of several classification criteria and report that a combination of criteria based on acoustic startle responses and behavior in an anxiogenic environment is a reliable predictor of a PTSD-like phenotype.There are individual predispositions to developing impaired extinction and elevated acoustic startle that can be identified after exposure to a mildly stressful event, which by itself does not induce such a behavioral phenotype. The model presented here is a valuable tool for studying the etiology and pathophysiology of anxiety disorders and provides a platform for testing behavioral and pharmacological interventions that can reduce the probability of developing pathologic behaviors associated with such disorders

Variation in Molybdenum Content Across Broadly Distributed Populations of Arabidopsis thaliana Is Controlled by a Mitochondrial Molybdenum Transporter (MOT1)

Molybdenum (Mo) is an essential micronutrient for plants, serving as a cofactor for enzymes involved in nitrate assimilation, sulfite detoxification, abscisic acid biosynthesis, and purine degradation. Here we show that natural variation in shoot Mo content across 92 Arabidopsis thaliana accessions is controlled by variation in a mitochondrially localized transporter (Molybdenum Transporter 1 - MOT1) that belongs to the sulfate transporter superfamily. A deletion in the MOT1 promoter is strongly associated with low shoot Mo, occurring in seven of the accessions with the lowest shoot content of Mo. Consistent with the low Mo phenotype, MOT1 expression in low Mo accessions is reduced. Reciprocal grafting experiments demonstrate that the roots of Ler-0 are responsible for the low Mo accumulation in shoot, and GUS localization demonstrates that MOT1 is expressed strongly in the roots. MOT1 contains an N-terminal mitochondrial targeting sequence and expression of MOT1 tagged with GFP in protoplasts and transgenic plants, establishing the mitochondrial localization of this protein. Furthermore, expression of MOT1 specifically enhances Mo accumulation in yeast by 5-fold, consistent with MOT1 functioning as a molybdate transporter. This work provides the first molecular insight into the processes that regulate Mo accumulation in plants and shows that novel loci can be detected by association mapping

Amplification of cox2 (∼620 bp) from 2 mg of Up to 129 Years Old Herbarium Specimens, Comparing 19 Extraction Methods and 15 Polymerases

During the past years an increasing number of studies have focussed on the use of herbarium specimens for molecular phylogenetic investigations and several comparative studies have been published. However, in the studies reported so far usually rather large amounts of material (typically around 100 mg) were sampled for DNA extraction. This equals an amount roughly equivalent to 8 cm2 of a medium thick leaf. For investigating the phylogeny of plant pathogens, such large amounts of tissue are usually not available or would irretrievably damage the specimens. Through systematic comparison of 19 DNA extraction protocols applied to only 2 mg of infected leaf tissue and testing 15 different DNA polymerases, we could successfully amplify a mitochondrial DNA region (cox2; ∼620 bp) from herbarium specimens well over a hundred years old. We conclude that DNA extraction and the choice of DNA polymerase are crucial factors for successful PCR amplification from small samples of historic herbarium specimens. Through a combination of suitable DNA extraction protocols and DNA polymerases, only a fraction of the preserved plant material commonly used is necessary for successful PCR amplification. This facilitates the potential use of a far larger number of preserved specimens for molecular phylogenetic investigation and provides access to a wealth of genetic information in preserved in specimens deposited in herbaria around the world without reducing their scientific or historical value

B-cell lymphoma in retrieved femoral heads: a long term follow up

<p>Abstract</p> <p>Background</p> <p>A relatively high incidence of pathological conditions in retrieved femoral heads, including a group of patients having low grade B-cell lymphoma, has been described before. At short term follow up none of these patients with low-grade B-cell lymphoma showed evidence of systemic disease. However, the long term follow up of these patients is not known.</p> <p>Methods</p> <p>From November 1994 up to and including December 2005 we screened all femoral heads removed at the time of primary total hip replacement histopathologically and included them in the bone banking protocol according to the guidelines of the American Associations of Tissue Banks (AATB) and the European Association of Musculo-Skeletal Transplantation (EAMST). We determined the percentage of B-cell lymphoma in all femoral heads and in the group that fulfilled all criteria of the bone banking protocol and report on the long-term follow-up.</p> <p>Results</p> <p>Of 852 femoral heads fourteen (1.6%) were highly suspicious for low-grade B-cell lymphoma. Of these 852 femoral heads, 504 were eligible for bone transplantation according to the guidelines of the AATB and the EAMST. Six femoral heads of this group of 504 were highly suspicious for low-grade B-cell lymphoma (1.2%). At long term follow up two (0.2%) of all patients developed systemic malignant disease and one of them needed medical treatment for her condition.</p> <p>Conclusion</p> <p>In routine histopathological screening we found variable numbers of low-grade B-cell lymphoma throughout the years, even in a group of femoral heads that were eligible for bone transplantation. Allogenic transmission of malignancy has not yet been reported on, but surviving viruses are proven to be transmissible. Therefore, we recommend the routine histopathological evaluation of all femoral heads removed at primary total hip arthroplasty as a tool for quality control, whether the femoral head is used for bone banking or not.</p

Radiation-induced cancer after radiotherapy for non-Hodgkin's lymphoma of the head and neck: a retrospective study

<p>Abstract</p> <p>Background</p> <p>survivors of non-Hodgkin's lymphoma (NHL) are well known to be at an increased risk of second malignancies. In this study, we evaluated the incidence and clinical features of head and neck cancer (HNC) occurring after radiotherapy (RT) for NHL.</p> <p>Materials and methods</p> <p>We investigated the clinical records of 322 patients who had received RT for early-stage NHL of the head and neck at our institute between 1952 and 2000.</p> <p>Results</p> <p>There were 4 patients with a second HNC developing in the irradiated field, consisting of 2 patients with gum cancer, 1 case with tongue cancer and 1 case with maxillary sinus cancer. The pathological diagnosis in all the 4 patients was squamous cell carcinoma (SCC). Two of the patients (one with gum cancer and one with maxillary sinus cancer) died of the second HNC, while the remaining 2 patients are still living at the time of writing after therapy for the second HNC, with neither recurrence of the second tumor nor relapse of the primary tumor. The ratio of the observed to the expected number (O/E ratio) of a second HNC was calculated to be 12.7 (95%CI, 4.07–35.0), and the absolute excess risk (AER) per 10,000 person-years was 13.3. The median interval between the RT and the diagnosis of the second HNC was 17.0 years (range, 8.7 to 22.7 years).</p> <p>Conlusion</p> <p>The risk of HNC significantly increased after RT for early-stage NHL. These results suggest that second HNC can be regarded as one of the late complications of RT for NHL of the head and neck.</p

Measurement of the Bottom-Strange Meson Mixing Phase in the Full CDF Data Set

We report a measurement of the bottom-strange meson mixing phase \beta_s using the time evolution of B0_s -> J/\psi (->\mu+\mu-) \phi (-> K+ K-) decays in which the quark-flavor content of the bottom-strange meson is identified at production. This measurement uses the full data set of proton-antiproton collisions at sqrt(s)= 1.96 TeV collected by the Collider Detector experiment at the Fermilab Tevatron, corresponding to 9.6 fb-1 of integrated luminosity. We report confidence regions in the two-dimensional space of \beta_s and the B0_s decay-width difference \Delta\Gamma_s, and measure \beta_s in [-\pi/2, -1.51] U [-0.06, 0.30] U [1.26, \pi/2] at the 68% confidence level, in agreement with the standard model expectation. Assuming the standard model value of \beta_s, we also determine \Delta\Gamma_s = 0.068 +- 0.026 (stat) +- 0.009 (syst) ps-1 and the mean B0_s lifetime, \tau_s = 1.528 +- 0.019 (stat) +- 0.009 (syst) ps, which are consistent and competitive with determinations by other experiments.Comment: 8 pages, 2 figures, Phys. Rev. Lett 109, 171802 (2012