Commercial Devices (commercial + device)

Distribution by Scientific Domains


Selected Abstracts


Commercial devices measuring UV radiation: a good choice for the public?

PHOTODERMATOLOGY, PHOTOIMMUNOLOGY & PHOTOMEDICINE, Issue 5 2010
Alberto Pettazzi
Commercial devices measuring UV radiation are available on the market at affordable prices. This work presents the response of six commercial devices in comparison to UV index measurements and in relation to the guidelines provided by the INTERSUN programme. Taking everything into account, overestimated or non-standard data, and ambiguous or incomplete information was found. Instead of using these gadgets, people should refer to official information and advice provided by health and weather services. [source]


The evaporation method: Extending the measurement range of soil hydraulic properties using the air-entry pressure of the ceramic cup

JOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 4 2010
Uwe Schindler
Abstract Knowledge of hydraulic functions is required for various hydrological and plant-physiological studies. The evaporation method is frequently used for the simultaneous determination of hydraulic functions of unsaturated soil samples, i.e., the water-retention curve and hydraulic-conductivity function. All methodic variants of the evaporation method suffer from the limitation that the hydraulic functions can only be determined to a mean tension of , 60 kPa. This is caused by the limited measurement range of the tensiometers of typically 80 kPa on the dry end. We present a new, cost- and time-saving approach which overcomes this restriction. Using the air-entry pressure of the tensiometer's porous ceramic cup as additional defined tension value allows the quantification of hydraulic functions up to close to the wilting point. The procedure is described, uncertainties are discussed, and measured as well as simulated test results are presented for soil samples of various origins, different textures (sand, loam, silt, clay, and peat) and variable dry bulk density. The experimental setup followed the system HYPROP which is a commercial device with vertically aligned tensiometers that is optimized to perform evaporation measurements. During the experiment leaked water from the tensiometer interior wets the surrounding soil of the tensiometer cup and can lead to a tension retardation as shown by simulation results. This effect is negligible when the tensiometers are embedded vertically. For coarsely textured soils and horizontal tensiometer alignment, however, the retardation must be considered for data evaluation. [source]


Sonophoresis: recent advancements and future trends

JOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 6 2009
Rekha Rao
Abstract Objectives Use of ultrasound in therapeutics and drug delivery has gained importance in recent years, evident by the increase in patents filed and new commercial devices launched. The present review discusses new advancements in sonophoretic drug delivery in the last two decades, and highlights important challenges still to be met to make this technology of more use in the alleviation of diseases. Key findings Phonophoretic research often suffers from poor calibration in terms of the amount of ultrasound energy emitted, and therefore current research must focus on safety of exposure to ultrasound and miniaturization of devices in order to make this technology a commercial reality. More research is needed to identify the role of various parameters influencing sonophoresis so that the process can be optimized. Establishment of long-term safety issues, broadening the range of drugs that can be delivered through this system, and reduction in the cost of delivery are issues still to be addressed. Summary Sonophoresis (phonophoresis) has been shown to increase skin permeability to various low and high molecular weight drugs, including insulin and heparin. However, its therapeutic value is still being evaluated. Some obstacles in transdermal sonophoresis can be overcome by combination with other physical and chemical enhancement techniques. This review describes recent advancements in equipment and devices for phonophoresis, new formulations tried in sonophoresis, synergistic effects with techniques such as chemical enhancers, iontophoresis and electroporation, as well as the growing use of ultrasound in areas such as cancer therapy, cardiovascular disorders, temporary modification of the blood-brain barrier for delivery of imaging and therapeutic agents, hormone replacement therapy, sports medicine, gene therapy and nanotechnology. This review also lists patents pertaining to the formulations and techniques used in sonophoretic drug delivery. [source]


Commercial devices measuring UV radiation: a good choice for the public?

PHOTODERMATOLOGY, PHOTOIMMUNOLOGY & PHOTOMEDICINE, Issue 5 2010
Alberto Pettazzi
Commercial devices measuring UV radiation are available on the market at affordable prices. This work presents the response of six commercial devices in comparison to UV index measurements and in relation to the guidelines provided by the INTERSUN programme. Taking everything into account, overestimated or non-standard data, and ambiguous or incomplete information was found. Instead of using these gadgets, people should refer to official information and advice provided by health and weather services. [source]


Numerical Simulation of Thrombus Aspiration in Two Realistic Models of Catheter Tips

ARTIFICIAL ORGANS, Issue 4 2010
Giancarlo Pennati
Abstract Thrombus aspiration catheters are devices used to remove a blood clot from a vessel, usually prior to angioplasty or stent implantation. However, in vitro results showed that the use of different commercial devices could produce very different thrombus removals, suggesting a primary dependence on the distal tip configuration of the catheter. A computational methodology based on realistic catheter tip modeling was developed to investigate the factors affecting the thrombus suction. Two different designs were considered, either with a single central lumen or a combination of central and side holes. First, steady-state aspiration of distilled water from a reservoir was simulated and compared with experimental tests. Subsequently, the aspiration of a totally occlusive thrombus, modeled as a high viscous fluid, was simulated solving a complex two-phase (blood and thrombus) problem. In particular, the benefit of additional openings was investigated. Good matching between the steady-state experimental and numerically simulated hydraulic behaviors allowed a validation of the numerical models. Numerical results of thrombus aspiration showed that the catheter with central and side holes had a worse performance if compared with the single central lumen catheter. Indeed, the inlets in contact with both blood and thrombus preferentially aspirate blood due to its much lower viscosity. This effect hindered the aspiration of thrombus. The amount of aspirated thrombus highly depends on the complex, two-phase fluid dynamics occurring across the catheter tips. Results suggested that location of additional holes is crucial in the catheter aspiration performance. [source]