Wearable monitoring of lumbar spine curvature by inertial and e-textile sensory fusion.

This paper describes the design, the development and the preliminary testing of a wearable system able perform a real time estimation of the local curvature and the length of the spine lumbar arch. The system integrate and fuse information gathered from textile based piezoresistive sensor arrays and tri-axial accelerometers. E-textile strain sensing garments suffer from non-linearities, hysteresis and long transient, while accelerometers, used as inclinometers, present biased values and are affected by the system acceleration due to subject movements. In this work, focused on the wearability and comfort of the user, we propose a fusion of the information deriving from the two class of sensors to reduce their intrinsic errors affecting measurements. Comparative evaluation of system performances with stereophotogrammetric techniques shows a 2% error in lumbar arch length reconstruction.

Artificial kinesthetic systems for telerehabilitation.

Artificial sensory motor systems are now under development in a truly wearable form using an innovative technology based on electroactive polymers. The integration of electroactive polymeric materials into wearable garments endorses them with strain sensing and mechanical actuation properties. The methodology underlying the design of haptic garments has necessarily to rely on knowledge of biological perceptual and motor processes which is, however, scattered and fragmented. Notwithstanding, the combined use of new polymeric electroactive materials in the form of fibers and fabrics with emerging concepts of biomimetic nature in sensor data analysis, pseudomuscular actuator control and biomechanical design may not only provide new avenues toward the realization of truly wearable kinesthetic and haptic interfaces, but also clues and instruments to better comprehend human manipulative and gestual functions. In this talk the conception, early stage implementation and preliminary testing of a fabric-based wearable interface endowed with spatially redundant strain sensing and distributed actuation are illustrated with reference to a wearable upper limb artificial kinesthesia system, intended to be used in telerehabilitation of post stroke patient.

Strain sensing fabric for hand posture and gesture monitoring.

Monitoring body kinematics and analyzing posture and gesture is an area of major importance in bioengineering and several other connected disciplines such as rehabilitation, sport medicine and ergonomics. Recent developments of new smart materials consent the realization of a new generation of garments with distributed sensors. What we present here is a sensing glove able to detect the posture and movements of the hand.

Use of pure t-butanol as a solvent for freeze-drying: a case study.

1-(2-Chloroethyl)-3-sarcosinamide-1-nitrosourea, (SarCNU) (NSC-364432) is a new antitumor drug that is of interest to the National Cancer Institute. It is intended for use as an intravenous injection. Although SarCNU is sufficiently soluble in water to obtain the desired dosage, it is highly unstable. Its T(90) in aqueous solution at room temperature is less than 6 h. Neat tertiary butyl alcohol (TBA), a low toxicity, high vapor pressure and low melting solvent, was determined to be an excellent freeze-drying medium. Lyophilization of SarCNU from pure TBA produces a uniform cake composed of needle-shaped crystals. Thermal analysis and gas chromatography indicate that the cake contains less than 0.001% residual solvent. The SarCNU cake can be readily reconstituted with either water or an aqueous solution of 40% propylene glycol and 10% ethanol. The reconstituted solutions are stable for 4 and 13 h, respectively.

The preparation of soft gelatin capsules for a radioactive tracer study.

Clinical doses are developed for the oral coadministration of radiolabeled and nonlabeled forms of a poorly soluble investigational compound: OPC-41061. The release rates of the labeled and nonlabeled forms are equated and matched to the release rate of the polymer spray-dried form of the drug in the proposed market product. The study involves the physicochemical characterization of the powders using thermal analysis and dissolution testing, development and extemporaneous manufacture of liquid-filled soft gelatin capsules, and dissolution and stability testing of the final dosage form. Thermal analysis indicated that the labeled powder was amorphous and that the nonlabeled powder, which had been jet-milled, was crystalline. Dissolution testing of the jet-milled and spray-dried powders indicated that the former was released at a significantly slower rate. A liquid formulation containing 25% dimethyl acetamide and 75% polyethylene glycol 400 (PEG 400) solubilized the desired dose of 60 mg and exhibited a drug profile that was similar to the spray-dried formulation. The final formulation was a soft gelatin capsule containing 60 mg of drug, including 100 microCi radioactivity, dissolved in 0.8 ml of a 25% dimethyl acetamide/75% PEG 400 solution. The formulation was chemically and physically stable for a period greater than the duration of the study.

Freeze-drying above room temperature.

This study investigates the use of solid, organic compounds to lyophilize drugs without conventional freeze-drying equipment. The aim of the investigation is to find a pharmaceutically acceptable solvent or solvent combination that is appropriate for freeze-drying on the basis of its ability to (1) solubilize hydrophobic drugs, (2) provide a stable environment for water-sensitive compounds, (3) be rapidly and completely removed from the product under vacuum, and (4) produce cakes that are readily reconstituted. A eutectic formed from 1,1,1-trichloro-2-methyl-2-propanol (chlorobutanol) hemihydrate and dimethyl sulfone (DMSO2) is determined to be a suitable medium.

A novel thermogravimetric method for estimating the saturated vapor pressure of low-volatility compounds.

Thermogravimetric analysis is used to measure accelerated vaporization rates at elevated temperatures and reduced pressures for several compounds. Multiple linear regression is used to generate empirical coefficients of an equation that relates these parameters. The vaporization rates of the compounds at standard ambient temperature and pressure (SATP) are estimated by extrapolation to 10(5) Pa (1 atm) and 298 K. The estimated vaporization rates are then correlated with literature values of saturated vapor pressure (Psat). The results of twenty four compounds with vapor pressures that span 10 orders of magnitude indicate that p25 degrees C (sat) is directly proportional to the rate of vaporization at SATP. The average error of an estimate of p25 degrees C (sat) based on this relationship is less than a factor of 2.1.

A method for the rapid estimation of sublimation rates of organic compounds at standard temperature and pressure.

A method for the rapid estimation of the sublimation rates of organic compounds at standard temperature and pressure (STP; 298 K and 101.3 kPa, respectively) is presented. Thermogravimetric analysis was used to obtain accelerated sublimation rates for anthracene at a series of elevated temperatures and reduced pressures. An empirical equation relating these parameters was used to extrapolate to the STP sublimation rate. This value is in good agreement with the measured value.