Monolithic flux transformer-coupled high-Tc dc SQUID magnetometers

YBa/sub 2/Cu/sub 3/O/sub 7-x/ based monolithic flux transformer-coupled high-T/sub c/ DC SQUID magnetometers operating up to 73 K have been realized. The devices are characterized by high values of the modulation voltage, up to 32 /spl mu/V at 40 K. A minimal white noise level of 0.10 pT//spl radic/Hz was obtained above 200 Hz, and 0.64 pT//spl radic/Hz at 1 Hz and 55 K. The temperature dependence of the modulation voltage, the effective sensing area and the field sensitivity are discussed. Model-calculations have been performed to investigate high frequency resonances in the washer-input coil structure. Methods for damping are considered

Languages at play: The relevance of L1 attrition to the study of bilingualism

Speakers who routinely use more than one language may not use any of their languages in ways which are exactly like that of a monolingual speaker. In sequential bilingualism, for example, there is often evidence of interference from the L1 in the L2 system. Describing these interference phenomena and accounting for them on the basis of theoretical models of linguistic knowledge has long been a focus of interest of Applied Linguistics. More recently, research has started to investigate linguistic traffic which goes the other way: L2 interferences and contact phenomena evident in the L1. Such phenomena are probably experienced to some extent by all bilinguals. They are, however, most evident among speakers for whom a language other than the L1 has started to play an important, if not dominant, role in everyday life (Schmid and K�pke, 2007). This is the case for migrants who move to a country where a language is spoken which, for them, is a second or foreign language. We refer to the phenomena of L1 change and L2 interference which can be observed in such situations as language attrition

Disease management with home telemonitoring aimed at substitution of usual care in the Netherlands: Post-hoc analyses of the e-Vita HF study

BACKGROUND: Home telemonitoring in heart failure (HF) patients may reduce workload of HF nurses by reducing face-to-face contacts. The aim of this study is to assess whether telemonitoring as a substitution could have negative effects as expressed by less reduction in circulating natriuretic peptide levels between baseline and one-year of follow up compared to usual care. METHODS: A post-hoc analysis of the e-Vita HF trial, a three-arm parallel randomized trial conducted in stable HF patients. Patients were randomized into three arms: (i) usual HF outpatient care, (ii) usual care combined with the use of the website heartfailurematters.org, and (iii) telemonitoring (e-Vita HF platform) instead of face-to-face consultations. Mixed linear model analyses were applied to assess differences in the N-terminal prohormone of brain natriuretic peptide (NT-proBNP) levels between the three arms over a year. RESULTS: A total of 223 participants could be included (mean age 67.1 ± 10.1 years, 27% women, New York Heart Association class I–IV; 39%, 38%, 14%, and 9%). The mean left ventricular ejection fraction was 35 ± 10%. The median of routine face-to-face contacts over a year was 1.0 lower (2.0 vs. 3.0) in the third arm compared with usual care. Median NT-proBNP levels did not significantly differ between the three arms. CONCLUSION: In stable and optimally treated HF patients, telemonitoring causing a reduction of routine face-to-face contacts seems not to negatively affect hemodynamic status as measured by NT-proBNP levels over time

New dynamics in cerebellar Purkinje cells: torus canards

We describe a transition from bursting to rapid spiking in a reduced mathematical model of a cerebellar Purkinje cell. We perform a slow-fast analysis of the system and find that -- after a saddle node bifurcation of limit cycles -- the full model dynamics follow temporarily a repelling branch of limit cycles. We propose that the system exhibits a dynamical phenomenon new to realistic, biophysical applications: torus canards.Comment: 4 pages; 4 figures (low resolution); updated following peer-review: language and definitions updated, Figures 1 and 4 updated, typos corrected, references added and remove

The FLUKA code for application of Monte Carlo methods to promote high precision ion beam therapy

Monte Carlo (MC) methods are increasingly being utilized to support several aspects of commissioning and clinical operation of ion beam therapy facilities. In this contribution two emerging areas of MC applications are outlined. The value of MC modeling to promote accurate treatment planning is addressed via examples of application of the FLUKA code to proton and carbon ion therapy at the Heidelberg Ion Beam Therapy Center in Heidelberg, Germany, and at the Proton Therapy Center of Massachusetts General Hospital (MGH) Boston, USA. These include generation of basic data for input into the treatment planning system (TPS) and validation of the TPS analytical pencil-beam dose computations. Moreover, we review the implementation of PET/CT (Positron-Emission-Tomography / Computed- Tomography) imaging for in-vivo verification of proton therapy at MGH. Here, MC is used to calculate irradiation-induced positron-emitter production in tissue for comparison with the +-activity measurement in order to infer indirect information on the actual dose delivery

Reducing Lighting Energy Use in Controlled Agricultural Environments

Photometric simulations using both daylight and electric lighting were performed to compare the energy use of conventional high-pressure sodium (HPS) greenhouse lighting to that of light-emitting diode (LED) lighting. Photometric simulations of a hypothetical greenhouse were performed in three different geographic locations in the United States with widely different annual daylight availability: Albany, NY, Fairbanks, AK, and Phoenix, AZ. Simulation conditions included summer and winter, overcast and clear skies, and several lighting layouts and distributions. The analysis showed that, while maintaining the criteria levels of photosynthetic photon flux density, lighting energy savings were primarily attributable to increased LED source efficacy rather than HPS. Secondary energy savings were attributable to the ability to continuously dim LED lighting in response to daily and seasonal changes in daylight. Despite options for LED luminaires with a slim form factor, reduced crop shading compared with larger conventional HPS luminaires did not result in significant lighting energy savings