MiniGRAIL progress report 2004

The MiniGRAIL detector was improved. The sphere was replaced by a slightly larger one, having a diameter of 68 cm (instead of 65 cm), reducing the resonant frequency by about 200 Hz to around 2.9 kHz. The last four masses of the attenuation system were machined to increase their resonant frequency and improve the attenuation around the resonant frequency of the sphere. In the new sphere, six holes were machined on the TIGA positions for easy mounting of the transducers. During the last cryogenic run, two capacitive transducers and a calibrator were mounted on the sphere. The first transducer was coupled to a double-stage SQUID amplifier having a commercial quantum design SQUID as a first stage and a DROS as a second stage. The second transducer was read by a single-stage quantum design SQUID. During the cryogenic run, the sphere was cooled down to 4 K. The two-stage SQUID had a flux noise of about 1.6 μ0 Hz−1/2. The detector was calibrated and the sensitivity curve of MiniGRAIL was determined

Hypotheses, evidence and relationships: The HypER approach for representing scientific knowledge claims

Biological knowledge is increasingly represented as a collection of (entity-relationship-entity) triplets. These are queried, mined, appended to papers, and published. However, this representation ignores the argumentation contained within a paper and the relationships between hypotheses, claims and evidence put forth in the article. In this paper, we propose an alternate view of the research article as a network of 'hypotheses and evidence'. Our knowledge representation focuses on scientific discourse as a rhetorical activity, which leads to a different direction in the development of tools and processes for modeling this discourse. We propose to extract knowledge from the article to allow the construction of a system where a specific scientific claim is connected, through trails of meaningful relationships, to experimental evidence. We discuss some current efforts and future plans in this area

Sensitivity of the spherical gravitational wave detector MiniGRAIL operating at 5 K

We present the performances and the strain sensitivity of the first spherical gravitational wave detector equipped with a capacitive transducer and read out by a low noise two-stage SQUID amplifier and operated at a temperature of 5 K. We characterized the detector performance in terms of thermal and electrical noise in the system output sygnal. We measured a peak strain sensitivity of $1.5\cdot 10^{-20} Hz^{-1/2}$ at 2942.9 Hz. A strain sensitivity of better than $5\cdot 10{-20}Hz{-1/2}$ has been obtained over a bandwidth of 30 Hz. We expect an improvement of more than one order of magnitude when the detector will operate at 50 mK. Our results represent the first step towards the development of an ultracryogenic omnidirectional detector sensitive to gravitational radiation in the 3kHz range.Comment: 8 pages, 5 figures, submitted to Physical Review

On the Sensitivity of a Hollow Sphere as a Multi-modal Resonant Gravitational Wave Detector

We present a numerical analysis to simulate the response of a spherical resonant gravitational wave detector and to compute its sensitivity. Under the assump- tion of optimal filtering, we work out the sensitivity curve for a sphere first taking into account only a single transducer, and then using a coherent analysis of the whole set of transducers.Comment: 24 pages, 11 figures, published versio

Don’t shoot the messenger:traffic-irrelevant messages on variable message signs (VMSs) might not interfere with traffic management

Road authorities struggle with the question whether variable message signs (VMSs) should exclusively be used for traffic management or could also be used to display traffic-irrelevant messages, such as mottos or commercial advertisements. The current study assesses behavioural responses to a critical route instruction displayed on the same VMS that previously displayed a variety of traffic-irrelevant messages. For this, thirty-two participants were divided between a control group and an experimental group (the advertisements group). In a driving simulator, all were familiarised with the same route by driving a VMS-equipped motorway nine times. For the advertisements group, up to drive 8, this VMS displayed various advertisements. Whereas for the control group it was blank. In the 9th drive, the VMS displayed a critical detour message for all participants. This critical route instruction – informing drivers to take the nearest exit – resulted in compliant driver behaviour in the advertisements group. In addition, they only reduced speed marginally to increase the time to process the VMS text. The control group, on the contrary, displayed a much sharper speed reduction; though the instruction only moderately altered motorway exit behaviour. What is more, the 31% (n = 4) of the advertisements group who complied with the critical route instruction subsequently failed to recall this message (recalling an advertisement instead). In conclusion, this study provides evidence that displaying traffic-irrelevant messages on VMSs might not interfere with traffic management; provided the format of said messages is in accordance with ergonomic VMS guidelines as used in this study. It is proposed that due to repeated exposure to various VMS texts, reading the sign has been practised to the extent that little to no conscious deliberation was required. As a result, recall of what was seen, proved to be an inadequate proxy for assessing driver behaviour. This study shows that conscious attention might not be a prerequisite for compliance. Furthermore, it suggests that continuous variability in objects in the traffic environment may become part of a subconscious monitoring process, as long as they have been sufficiently practised

How visually impaired cyclists ride regular and pedal electric bicycles

The present study investigates whether visually impaired cyclists compensate for their vision limitations by maintaining a lower speed or a larger distance to the kerb than normally sighted cyclists when riding a regular bicycle or pedal electric bicycle (pedelec). A normally sighted control group (n = 10), a peripheral visual field loss group (n = 9), and a low visual acuity group (n = 12) rode a fixed route (7.5 km) in the Netherlands on a regular bicycle and on a pedelec. Speed and lateral position were measured when participants cycled a (I) one-way cycle path, (II) two-way cycle path, (III) residential area, and (IV) shared space zone. With regard to both the regular bicycle and the pedelec, no significant speed or lateral position differences were found between the three groups. In conclusion, for some people with severe and permanent visual impairments, and under certain circumstances, regular bicycle and pedelec riding may be possible without noticeable speed reduction or adapted lane position to compensate for their functional impairment. The present findings may further optimise the cycling advice provided by mobility trainers of vision rehabilitation centres and the independent mobility of visually impaired people

Identification of a methylation panel as an alternative triage to detect CIN3+ in hrHPV-positive self-samples from the population-based cervical cancer screening programme

Background: The Dutch population-based cervical cancer screening programme (PBS) consists of primary high-risk human papilloma virus (hrHPV) testing with cytology as triage test. In addition to cervical scraping by a general practitioner (GP), women are offered self-sampling to increase participation. Because cytological examination on self-sampled material is not feasible, collection of cervical samples from hrHPV-positive women by a GP is required. This study aims to design a methylation marker panel to detect CIN3 or worse (CIN3+) in hrHPV-positive self-samples from the Dutch PBS as an alternative triage test for cytology.Methods: Fifteen individual host DNA methylation markers with high sensitivity and specificity for CIN3+ were selected from literature and analysed using quantitative methylation-specific PCR (QMSP) on DNA from hrHPV-positive self-samples from 208 women with CIN2 or less (&lt; CIN2) and 96 women with CIN3+. Diagnostic performance was determined by area under the curve (AUC) of receiver operating characteristic (ROC) analysis. Self-samples were divided into a train and test set. Hierarchical clustering analysis to identify input methylation markers, followed by model-based recursive partitioning and robustness analysis to construct a predictive model, was applied to design the best marker panel.Results: QMSP analysis of the 15 individual methylation markers showed discriminative DNA methylation levels between &lt; CIN2 and CIN3+ for all markers (p &lt; 0.05). The diagnostic performance analysis for CIN3+ showed an AUC of ≥ 0.7 (p &lt; 0.001) for nine markers. Hierarchical clustering analysis resulted in seven clusters with methylation markers with similar methylation patterns (Spearman correlation&gt; 0.5). Decision tree modeling revealed the best and most robust panel to contain ANKRD18CP, LHX8 and EPB41L3 with an AUC of 0.83 in the training set and 0.84 in the test set. Sensitivity to detect CIN3+ was 82% in the training set and 84% in the test set, with a specificity of 74% and 71%, respectively. Furthermore, all cancer cases (n = 5) were identified.Conclusion: The combination of ANKRD18CP, LHX8 and EPB41L3 revealed good diagnostic performance in real-life self-sampled material. This panel shows clinical applicability to replace cytology in women using self-sampling in the Dutch PBS programme and avoids the extra GP visit after a hrHPV-positive self-sampling test.</p