The Experts below are selected from a list of 186 Experts worldwide ranked by ideXlab platform

Schnetzer Astrid - One of the best experts on this subject based on the ideXlab platform.

Geist Simon - One of the best experts on this subject based on the ideXlab platform.

Teddy W Worrell - One of the best experts on this subject based on the ideXlab platform.

  • concurrent validity of upper extremity Volume estimates comparison of calculated Volume derived from girth measurements and water Displacement Volume
    Physical Therapy, 2003
    Co-Authors: Joy R Karges, Beth E Mark, Jill S Stikeleather, Teddy W Worrell
    Abstract:

    Background and Purpose. The Volume of all limbs can be determined by water Displacement methods or calculations derived from girth measurements. The purpose of this study was to determine the concurrent validity of calculated Volume and water Displacement Volume measurements. Subjects. Both upper extremities of 14 women with lymphedema were measured. Methods. Volumetric measurements were taken with a Volumeter, and circumferential measurements were taken with a tape measure. Calculated Volume was determined by summing segment Volumes derived from the truncated cone formula. Pearson product moment correlations, paired t tests, and linear regression tests were used to assess relative association and absolute differences between calculated and actual Volumes. Results. The correlation coefficient for calculated Volume versus upper extremity minus fingers (UE-F) water Displacement Volume was .99. Paired t tests showed differences between calculated Volume and UE-F water Displacement Volume ( t =−3.88, mean difference=−95.62 mL), and the linear regression slope was 0.83 with an intercept of 255.28 mL. Discussion and Conclusion. Calculated Volume measurements were highly associated with measurements based on water Displacement; therefore, clinicians should feel confident in using either calculated Volume or water Displacement Volume. The differences, however, indicated that the measures were not interchangeable. Thus, clinicians should not mix or substitute measurement methods with a single patient or in a single study.

Juergen Pauluhn - One of the best experts on this subject based on the ideXlab platform.

  • kinetic modeling of the retention and fate of inhaled cerium oxide nanoparticles in rats the cumulative Displacement Volume of agglomerates determines the outcome
    Regulatory Toxicology and Pharmacology, 2017
    Co-Authors: Juergen Pauluhn
    Abstract:

    This paper compares the pulmonary kinetics of inhaled nano-CeO2 from published repeated inhalation studies of 1-, 4-, 13-, and 52-week duration using a previously published kinetic model to simulate the pulmonary kinetics of inhaled micron-sized poorly soluble, low toxicity particles (PSPs) in rats. This comparative analysis demonstrates that the kinetic hallmarks characterizing lung overload-related pulmonary inflammation are indistinguishable for PSPs and agglomerated nano-CeO2. Unlike PSPs, nano-CeO2 appears to dissolve within the lung as long as tissue saturation has not been attained. When saturation is reached, the accumulated retained particle Displacement Volume becomes the prominent unifying factor interrelating the retained Volumetric particle dose and pulmonary inflammogenicity observed in inhalation studies of 1- to 52-weeks duration. In summary, the pulmonary kinetics of nano-CeO2 inhaled as micron-sized agglomerates exhibit kinetic and toxicological profiles similar to micron-sized PSPs. The coherence of modeled and empirical outcomes supports the hypothesis that the leading metric of pulmonary toxicity is the Displacement Volume of accumulated aggregated particles. Whereas agglomerated nano-CeO2 particles follow the typical kinetic of lung overload, evidence of dissolution of nano-CeO2 demonstrates a much shorter elimination half-time of t1/2 = 17 days. Thus, kinetic modeling approaches appear to not only deliver the highest degree of integrated mechanistic information, it also provides a validating feed-back loop to verify/refute the starting hypothesis of inhalation studies.

Choongsik Bae - One of the best experts on this subject based on the ideXlab platform.

  • effect of biofuels on nanoparticle emissions from spark and compression ignited single cylinder engines with same exhaust Displacement Volume
    Energy & Fuels, 2009
    Co-Authors: Jinwook Lee, R Patel, Alessandro Schonborn, Nicos Ladommatos, Choongsik Bae
    Abstract:

    Nanosized particles emitted from automotive engines continue to attract concern because of their adverse health effects and their impact on the environment. Automotive engines are a major source of fine and ultrafine particles emitted into the atmosphere. Through stricter emission regulations and the introduction of advanced technologies, the specific particulate mass emissions (in g/km and g/kWh) from internal combustion engines have decreased by about 1 order of magnitude since the 1980s. However, the number concentration of nanoparticles (No./m3) emitted from internal combustion engines may continue to increase considerably and has recently attracted the attention of the Particle Measurement Programme (PMP). This program is intended to evaluate engine nanoparticle measurement systems for use in future emission regulations. In the study reported in this paper, two latest-generation engines, one spark-ignited and the other compression-ignited, were used for a comparison of the particulate emission characteristics, including number density. Both engines were single-cylinder with the same Displacement Volume of 500 cm3, and neither included after-treatment traps or catalytic converters. Test fuels used for the study were: gasoline and E85 (mixture of 85% ethanol and 15% gasoline, sometimes called gasohol) for the spark-ignited engine having a compression ratio of 10; and ultralow sulfur diesel (ULSD) and BD100 (100% biodiesel, i.e. soybean methyl ester) for the compression-ignited engine having a compression ratio of 15. A fast-response particle spectrometer (DMS500) with heated sample line was used for continuous measurement of the particle size and number distribution in the size range of 5−1000 nm (aerodynamic diameter). The experimental results showed that particle number peaked within the range of 10−300 nm under all engine operating conditions, regardless of engine combustion type. An observed shift toward larger particle size with increasing engine load could be explained by particle coagulation. The effect of the different fuels on nanoparticle size distributions was dependent on the engine type (spark-ignition or compression-ignition).