654 research outputs found
Studies of YBCO Strip Lines under Voltage Pulses: Optimisation of the Design of Fault Current Limiters
We present experimental results on the behaviour of a superconducting YBCO/Au
meander of length L submitted to short circuit tests with constant voltage
pulses. The meander, at the beginning of the short-circuit, is divided in two
regions; one, with a length L1 proportional to the applied voltage, which first
switches into a highly dissipative state (HDS) while the rest remains
superconducting. Then the rest of the meander will progressively switch into
the normal state due to the propagation of this HDS (few m/s) from both ends.
The part L1 has to initially support a power density proportional to r.Jp^2 (r
is the resistivity of the bilayer and Jp the peak current density). To avoid
local excessive dissipation of power and over heating on one part of the wafer
in the initial period, we have developed a novel design in order to distribute
the dissipating section of the meander into many separated small dissipative
zones. Furthermore the apparent propagation velocity of these dissipative zones
is increased by the number of propagation fronts. We will show results obtained
on 3kW (300V, 10A) FCL on a 2" wafer which confirm the benefits of this new
design.Comment: 4 pages, 6 figures; presented at the Applied Superconductivity
Conference in Houston, TX (August 2002); to be published in IEEE Trans. On
Appl. Supercon
Role of Methyl Salicylate on Oviposition Deterrence in Arabidopsis thaliana.
Plants attacked by herbivores have evolved different strategies that fend off their enemies. Insect eggs deposited on leaves have been shown to inhibit further oviposition through visual or chemical cues. In some plant species, the volatile methyl salicylate (MeSA) repels gravid insects but whether it plays the same role in the model species Arabidopsis thaliana is currently unknown. Here we showed that Pieris brassicae butterflies laid fewer eggs on Arabidopsis plants that were next to a MeSA dispenser or on plants with constitutively high MeSA emission than on control plants. Surprisingly, the MeSA biosynthesis mutant bsmt1-1 treated with egg extract was still repellent to butterflies when compared to untreated bsmt1-1. Moreover, the expression of BSMT1 was not enhanced by egg extract treatment but was induced by herbivory. Altogether, these results provide evidence that the deterring activity of eggs on gravid butterflies is independent of MeSA emission in Arabidopsis, and that MeSA might rather serve as a deterrent in plants challenged by feeding larvae
The LHC Post Mortem Analysis Framework
The LHC with its unprecedented complexity and criticality of beam operation will need thorough analysis of data taken from systems such as power converters, interlocks and beam instrumentation during events like magnet quenches and beam loss. The causes of beam aborts or in the worst case equipment damage have to be revealed to improve operational procedures and protection systems. The correct functioning of the protection systems with their required redundancy has to be verified after each such event. Post mortem analysis software for the control room has been prepared with automated analysis packages in view of the large number of systems and data volume. This paper recalls the requirements for the LHC Beam Post Mortem System (PM) and the necessity for highly reliable data collection. It describes in detail the redundant architecture for data collection as well as the chosen implementation of a multi-level analysis framework, allowing for automated analysis and qualification of a beam dump event based on expert provided analysis modules. It concludes with an example of the data taken during first beam tests in September 2008 with a first version of the system
A white-light trap for Bose-Einstein condensates
We propose a novel method for trapping Bose-condensed atoms using a
white-light interference fringe. Confinement frequencies of tens of kHz can be
achieved in conjunction with trap depths of only a few micro-K. We estimate
that lifetimes on the order of 10 s can be achieved for small numbers of atoms.
The tight confinement and shallow depth permit tunneling processes to be used
for studying interaction effects and for applications in quantum information.Comment: 10 pages with 3 figure
Standardizing training for Pressurized Intraperitoneal Aerosol Chemotherapy.
PIPAC is a novel mode of intraperitoneal drug delivery for patients with peritoneal cancer (PC). PIPAC is a safe treatment with promising oncological results. Therefore, a structured training program is needed to maintain high standards and to guarantee safe implementation.
An international panel of PIPAC experts created by means of a consensus meeting a structured 2-day training course including essential theoretical content and practical exercises. For every module, learning objectives were defined and structured presentations were elaborated. This structured PIPAC training program was then tested in five courses.
The panel consisted of 12 experts from 11 different centres totalling a cumulative experience of 23 PIPAC courses and 1880 PIPAC procedures. The final program was approved by all members of the panel and includes 12 theoretical units (45 min each) and 6 practical units including dry-lab and live surgeries. The panel finalized and approved 21 structured presentations including the latest evidence on PIPAC and covering all mandatory topics. These were organized in 8 modules with clear learning objectives to be tested by 12 multiple-choice questions. Lastly, a structured quantifiable (Likert scale 1-5) course evaluation was created. The new course was successfully tested in five courses with 85 participants. Mean overall satisfaction with the content was rated at 4.79 (±0.5) with at 4.71 (±0.5) and at 4.61 (±0.7), respectively for course length and the balance between theory and practice.
The proposed PIPAC training program contains essential theoretical background and practical training enabling the participants to safely implement PIPAC
Geosciences Roadmap for Research Infrastructures 2025–2028 by the Swiss Geosciences Community
This community roadmap presents an integrative approach including the most urgent infrastructure requests for the future development of geosciences in Switzerland. It recommends to strengthen the multidisciplinary nature of the geosciences by putting all activities under the roof of the Integrated Swiss Geosciences supported by four specific research infrastructure pillars. The roadmap represents the view of the Swiss scientific community in the field of geosciences and is a formal element of the process to elaborate the Swiss Roadmap for Research Infrastructures 2023. This bottom-up contribution to the identification and selection of important national and international research infrastructures has been coordinated by the Swiss Academy of Sciences (SCNAT) on a mandate by the State Secretariat for Education, Research and Innovation (SERI).ISSN:2297-1564ISSN:2297-157
Frequency and genome load of Epstein-Barr virus in 509 breast cancers from different geographical areas
Since the few data exploring a possible association between Epstein–Barr virus (EBV) and breast cancer are conflicting, we investigated this association together with the influences of geographical areas. 509 breast cancers were sampled from areas with varying risks of nasopharynx carcinoma (NPC) such as North Africa (Algeria and Tunisia, high-risk area); southern France (Marseille, intermediate-risk area); and northern Europe (northern France, the Netherlands and Denmark; low-risk areas). Polymerase chain reaction (PCR) of a subregion of EBV BamHIC encoding the EBERs demonstrated that 31.8% of the tumours contained the viral genome. No significant differences were observed among the geographical areas. However, positive samples showed higher loads of the EBV genome in the NPC high- and intermediate-risk areas than in the low-risk areas. EBV type 1 was the dominant strain. In situ hybridization studies using a35S-labelled riboprobe for EBER1 and a laser capture microdissection, combined with quantitative PCR, showed that EBV localization was restricted to some tumour epithelial cell clusters. EBV could not be detected in the stroma. Considering the whole population covered, the presence of the EBV genome was not correlated with age, menopausal status, tumour, size, nodal status or histological grade. © 2001 Cancer Research Campaign http://www. bjcancer.co
Vibrotactile pedals : provision of haptic feedback to support economical driving
The use of haptic feedback is currently an underused modality in the driving environment, especially with respect to vehicle manufacturers. This exploratory study evaluates the effects of a vibrotactile (or haptic) accelerator pedal on car driving performance and perceived workload using a driving simulator. A stimulus was triggered when the driver exceeded a 50% throttle threshold, past which is deemed excessive for economical driving. Results showed significant decreases in mean acceleration values, and maximum and excess throttle use when the haptic pedal was active as compared to a baseline condition. As well as the positive changes to driver behaviour, subjective workload decreased when driving with the haptic pedal as compared to when drivers were simply asked to drive economically. The literature suggests that the haptic processing channel offers a largely untapped resource in the driving environment, and could provide information without overloading the other attentional resource pools used in driving
Feasibility and safety of PIPAC combined with additional surgical procedures: PLUS study.
PIPAC (Pressurized IntraPeritoneal Aerosol Chemotherapy) is a minimally invasive approach relying on physical principles for improving intraperitoneal drug delivery, including optimizing the homogeneity of drug distribution through an aerosol. Feasibility and safety of the new approach are now consolidated and data on its effectiveness are continuously increasing. Although any surgical procedure associated with PIPAC had always been discouraged due to the high risk of complications, surgical practice is constantly changing: with growing expertise, more and more surgical teams associate PIPAC with surgery.
PLUS study is part of the retrospective international cohort studies including 10 centers around the world (India, Italy, France, Germany, Belgium, Russia, Saudi Arabia, Switzerland) and 96 cases of combined approaches evaluated through a propensity score analysis.
the procedures most frequently associated with PIPAC were not only adhesiolysis, omentectomy, adnexectomy, umbilical/inguinal hernia repairs, but also more demanding procedures such as intestinal resections, gastrectomy, splenectomy, bowel repair/stoma creation. Although the evidence is currently limited, PLUS study demonstrated that PIPAC associated with additional surgical procedures is linked to an increase of surgical time (p < 0.001), length of stay (p < 0.001) and medical complication rate (p < 0.001); the most frequently reported medical complications were mild or moderate in severity, such as abdominal pain, nausea, ileus and hyperthermia. No difference in terms of surgical complications was registered; neither reoperation or postoperative deaths were reported.
these results suggest that PIPAC can be safely combined in expert centers with additional surgeries. Widespread change of practice should be discouraged before the results of ongoing prospective studies are available
Modeling the actinides with disordered local moments
A first-principles disordered local moment (DLM) picture within the
local-spin-density and coherent potential approximations (LSDA+CPA) of the
actinides is presented. The parameter free theory gives an accurate description
of bond lengths and bulk modulus. The case of -Pu is studied in
particular and the calculated density of states is compared to data from
photo-electron spectroscopy. The relation between the DLM description, the
dynamical mean field approach and spin-polarized magnetically ordered modeling
is discussed.Comment: 6 pages, 4 figure
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