A system for automatic measurement of circadian activity deviations in telemedicine

A system for the automatic measurement of the circadian activity deviations in telemedicine has been developed within the framework of a "Health Integrated Smart Home Information System" (HIS2). HIS2 is an experimental platform for the evaluation and the development of technologies in order to ensure the security and quality of life for patients who need home based medical monitoring. Location sensors are placed in each room of the HIS2, allowing the monitoring of patient's successive activity phases within the patient's home environment. We proceeded with a sampling in an hourly schedule to detect weak rhythmic variations. Based on numerous measurements, we established a mean value with confidence limits. These also allowed us to define a zone within which the patient's activity is qualified to be "predictable." Alerts are set off if the patient's activity deviates from this zone.     

On mixed-mode fracture of PVC foam

This paper reports on mixed-mode fracture in rigid cellular PVC foam based on experimental and numerical analyses. Experiments were performed on sharp-cracked specimens using the compact-tension-shear (CTS) test loading device. Foams of three different densities were tested. The CTS specimen was, in association with a special loading device, an appropriate apparatus for experimental mixed-mode fracture analysis. Experimentally-obtained fracture toughness results show good consistency. K_IC fracture toughness was marginally different in different directions. The ratio K_{II C}/K_{I C} was found to be between 0.4 and 0.65 depending on the foam density. For mixed-mode loading, Richard's criterion – using experimentally obtained K_{I C} and K_{II C} – was the best in predicting accurately fracture locus and fracture angle. When no experimental data were used, the maximum hoop stress criterion predicted best kinking angle. The principal strain criterion predicted the best fracture locus. Fracture boundary curve and kinking angle were best predicted for low mode II contribution. This revised version was published online in August 2006 with corrections to the Cover Date.     

Building an index of activity of inhabitants from their activity on the residential electrical power line

In the framework of context awareness within the home, our team is currently assessing the unobtrusive detection of inhabitants' activity through the monitoring of their use and consumption of electricity. The objective is to develop a system for the remote monitoring of large populations of elderly people living independently at home. To be readily deployable on the field, such a system must be minimally intrusive both for the home environment and for the field professionals (paramedics and social workers) visiting the patients at home. We carried out two successive field experiments to evaluate and to improve our system designed to deliver a single index of daily activity. The first experiment involved 13 elderly persons over a nine-month period (84,240 h data recorded) and the second one 12 elderly over six months (51,840 h). We evaluated both the relevance of the index and the acceptability of the system as a whole. We discovered that electrical activity is a kind of unique "signature" of each person's activity. Moreover, this profile provides unexpected information on the health status of the subject. We confirmed that the system was unobtrusive and well accepted both by the subjects and by the professionals involved. Our unique index of activity, and its trend over time, can provide timely information to the professionals on the patient.     

Multiple human 3D pose estimation from multiview images

Multimedia Tools and Applications - Multiple human 3D pose estimation is a challenging task. It is mainly because of large variations in the scale and pose of humans, fast motions, multiple persons...     

The effect of water suppression on the hepatic lipid quantification,as assessed by the LCModel,in a preclinical and clinical scenario

Objective

To investigate the effect of water suppression on the hepatic lipid quantification, using the LCModel.

Materials and methods

MR spectra with and without water suppression were acquired in the liver of mice at 4.7 T and patients at 3 T, and processed with the LCModel. The Cramér–Rao Lower Bound (CRLB) values of the seven lipid resonances were determined to assess the impact of water suppression on hepatic lipid quantification. A paired t test was used for comparison between the CRLBs obtained with and without water suppression.

Results

For the preclinical data, in the high (low) fat fraction subset an overall impairment in hepatic lipid quantification, i.e. an increase of CRLBs (no significant change of CRLBs) was observed in spectra acquired with water suppression. For the clinical data, there were no substantial changes in the CRLB with water suppression. Because (1) the water suppression does not overall improve the quantification of the lipid resonances and (2) the MR spectrum without water suppression is always acquired for fat fraction calculation, the optimal data-acquisition strategy for liver MRS is to acquire only the MR spectrum without water suppression.

Conclusion

For quantification of hepatic lipid resonances, it is advantageous to perform MR spectroscopy without water suppression in a clinical and preclinical scenario (at moderate fields).

     

Phase equilibrium data for aqueous solutions of formic acid with 2-ethyl-1-hexanol at T=(298.2, 308.2, 318.2, and 328.2) K

Liquid-liquid equilibrium (LLE) data for the system of (water+formic acid+2-ethyl-1-hexanol) were experimentally determined at T=(298.2, 308.2, 318.2, and 328.2) K and atmospheric pressure. A type-2 LLE was obtained for this ternary system. The influence of temperature on the equilibrium characteristics was found to be smallat the temperatures studied. Distribution coefficients and separation factors were calculated over the immiscibility regions. The experimental tie-line data were correlated using the UNIQUAC model. The values of the interaction parameters between each pair of the components were obtained for this thermodynamic model. The root mean square deviation (RMSD) between the observed and calculated mass fractions was 0.61%.     

ESMRMB 2016, 33rd Annual Scientific Meeting,Vienna, AT,September 29–October 1: Abstracts,Thursday

Objective

To evaluate the feasibility of in vivo measurement of the fatty acid (FA) composition of breast adipose tissue by MRS on a clinical platform.

Material and methods

MRS experiments were performed at 3 T, using a STEAM sequence, on 25 patients diagnosed with breast cancer. MR spectra, acquired on healthy breast tissue, were analysed with the LCModel.

Results

The measured values of the saturated fatty acid (SFA), mono-unsaturated fatty acid (MUFA) and poly-unsaturated fatty acid (PUFA) fractions were 23.8 ± 7.1 %, 55.4 ± 6.8 % and 20.8 ± 4.4 %, respectively.The values of SFA, MUFA and PUFA observed in the current study are in the same range as those found in two previous studies performed at 7 T.

Conclusion

The results of the current study show that it is possible to quantify the fatty acid composition of breast tissue in vivo in a clinical setting (3 T).

     

Telemonitoring of patients at home: a software agent approach

To address the issue of the increasing social, economical and medical needs of maintaining at home people in loss of autonomy while preserving privacy and quality of life, the authors present a software agent based telemonitoring and alarm raising system. The article describes the overall architecture, the various components of the model, and the methodology that has been used. It specifically addresses the issue of reflecting in the object oriented model of the system various dimensions including: the physical world of in-home bio-signal sensors, the numerical world of software agents and Internet-related technologies, and the medical and social worlds of patients, physicians and caregivers. In the model, the main stream of information goes from the biophysical world of patients at home to the socio-medical world of carers through a chain of devices including in-home sensors, local area network, home computer, remote server, and carers' computers. Each device hosts software agents with different levels of knowledge and complexity. Internet and Java technologies provide the building blocks of the designed telemonitoring software. Laboratory experiments have been realized using a fully equipped 'smart' demonstration home for telecare. The study takes place into a more general research project on 'smart' homes for telecare conducted at the Hospital Centre of Grenoble, France.     

Carbon nanotube films as electron field emitters

Carbon nanotubes have been recognized as one of the most promising electron field emitters currently available. We review the state of the art of current research on the electron field emission properties of carbon nanotube films and present recent results outlining their potential as field emitters as well as illustrating some current concerns in the research field.