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Selected AbstractsDoes diagnostic sonography alter thyroid and parathyroid hormone levels?JOURNAL OF CLINICAL ULTRASOUND, Issue 1 2008Erdinc Serin MD Abstract Purpose To investigate possible alterations in the levels of thyroid and parathyroid hormones (PTHs) and thyroglobulin (TG) in healthy individuals following diagnostic sonographic examination of the thyroid gland. Methods Thirty healthy women with no pathologic findings underwent sonographic examination, followed 6 weeks later by a second examination involving a probe-only application (PA) with the ultrasound scanner switched off. Duration times were identical for both examinations. Blood was drawn before and after the 2 applications. Thyroid hormone, PTH, and TG levels before and after the 2 applications were compared, and the difference between the variations for each parameter in the first and second applications was assessed. Blood samples were taken before and after the sonographic examination and the PA, and the serum concentrations of sensitive thyrotropin, total and free thyroxine, total and free tri-iodothyronine, TG, and PTH were measured. The pre- and post-examination levels of the hormones for the 2 applications were then compared and the difference between the variations for each parameter in the first and second application was then assessed. Results The only significant variations observed were in the TG levels after PA and PTH levels after both sonographic examination and PA. The comparison between the 2 difference values revealed no significant difference except for PTH. Conclusion This preliminary report on the possible influence of sonographic examination of the thyroid on the serum levels of thyroid and parathyroid hormones suggests that gland secretions such as PTH may be affected by external factors, including ultrasound. Clinicians should be aware of alterations in hormone levels by external factors. © 2007 Wiley Periodicals, Inc. J Clin Ultrasound, 2008 [source] Avoidance tests in site-specific risk assessment,influence of soil properties on the avoidance response of collembola and earthworms,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 5 2008Tiago Natal-da-Luz Abstract The ability of organisms to avoid contaminated soils can act as an indicator of toxic potential in a particular soil. Based on the escape response of earthworms and Collembola, avoidance tests with these soil organisms have great potential as early screening tools in site-specific assessment. These tests are becoming more common in soil ecotoxicology, because they are ecologically relevant and have a shorter duration time compared with standardized soil toxicity tests. The avoidance response of soil invertebrates, however, can be influenced by the soil properties (e.g., organic matter content and texture) that affect behavior of the test species in the exposure matrix. Such an influence could mask a possible effect of the contaminant. Therefore, the effects of soil properties on performance of test species in the exposure media should be considered during risk assessment of contaminated soils. Avoidance tests with earthworms (Eisenia andrei) and springtails (Folsomia candida) were performed to identify the influence of both organic matter content and texture on the avoidance response of representative soil organisms. Distinct artificial soils were prepared by modifying quantities of the standard artificial soil components described by the Organization for Economic Co-operation and Development to achieve different organic matter and texture classes. Several combinations of each factor were tested. Results showed that both properties influenced the avoidance response of organisms, which avoided soils with low organic matter content and fine texture. Springtails were less sensitive to changes in these soil constituents compared with earthworms, indicating springtails can be used for site-specific assessments of contaminated soils with a wider range of respective soil properties. [source] WATER ACTIVITY AND THE INACTIVATION OF ENTEROBACTER CLOACAE INOCULATED IN CHOCOLATE LIQUOR AND A MODEL SYSTEM BY PULSED ELECTRIC FIELD TREATMENTJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 5 2002S. MI Effects of water activity (aw) on the inactivation of Enterobacter cloacae inoculated in chocolate liquor and in a model system of 0.1% (w/v) peptone water and glycerol by pulsed electric field (PEF) treatment were investigated. An electric field strength of 24.5 kV/cm, a total treatment time of 320 ,s, a pulse duration time of 4 ,s, a pulse delay time of 15 ,s, and a pulse cycle time of 15 s were selected for PEF treatment. The inactivation ofE. cloacae by PEF increased significantly as aw increased (P < 0. 05). As aw of chocolate liquor increased from 0.48 to 0.89, the log reduction of E. cloacae increased from 0.1 to 1.3. The measured temperature change inside the PEF treatment chamber was 0.4C when the log reduction was 1. 3. Similarly, as aw increased from 0. 51 to 0.91 in the model system, the log reduction increased from 0.4 to 1.3. E. cloacae surviving a low aw environment had high resistance to PEF. PEF inactivated E. cloacae in the chocolate liquor with aw of 0.85 by 1 log at O h incubation. However, the log reduction was only 0.1 when PEF treatment was applied to E. cloacae which was incubated for 2 h in the chocolate liquor with aw of 0.85 before PEF treatment. E. cloacae surviving the low aw environment might have resistance not only to the low aw but also to PEF. The resistance to low aw environment may need to be considered when the inactivation of microorganisms by PEF is evaluated. [source] Multiresolution analysis on identification and dynamics of clusters in a circulating fluidized bedAICHE JOURNAL, Issue 3 2009Tung-Yu Yang Abstract A new wavelet-threshold criterion was developed to distinguish the cluster and the void phases from the transient solids holdup/concentration fluctuation signals when measured in a 108 mm-i.d. × 5.75 m-high circulating fluidized bed with FCC particles (dp = 78 ,m, ,p = 1,880 kg/m3). An appropriate level of approximation subsignal was systematically specified as a threshold for cluster identification, based on multiresolution analysis (MRA) of wavelet transformation. By the established threshold, the dynamic properties of clusters including the appearance time fraction of clusters Fcl, average cluster duration time ,cl, cluster frequency fcl, and local average solids holdup in clusters ,sc, at different radial and axial positions were determined under the turbulent, transition and fast fluidization flow regimes. The results also describe the dynamic properties of clusters and flow patterns in the splash zone along with the dense bottom region of the circulating fluidized beds. © 2009 American Institute of Chemical Engineers AIChE J, 2009 [source] The role of oral sensorimotor function in masticatory abilityJOURNAL OF ORAL REHABILITATION, Issue 3 2004K. Hirano summary, In order to investigate the relationship between oral sensorimotor ability and masticatory function, an oral stereognosis ability (OSA) test, masticatory performance and efficiency was employed for 15 dentate subjects. Subjects were instructed to orally identify OSA test pieces blindly. The response score and sum of the duration time for identification were used for analysis as OSA score and OSA response time. Masticatory function was evaluated using a sieving method with 3 g of peanuts. Masticatory performance was calculated with the weight percentage of portions finer than 1700 ,m by the total volume after 20 chewing strokes. Masticatory efficiency was calculated by the declination rate of median particle size which is defined by the Rosin,Rammler equation. To analyse the relationship between OSA variables and masticatory ability, the correlation coefficient was calculated. The results summarized as a significant correlation was found only between OSA score and masticatory efficiency. However, a significant correlation could not be found between other OAS variables and masticatory ability. It was revealed that positive correlation existed between oral stereognosis ability and masticatory ability. It was suggested that the role of oral sensorimotor function might affect the masticatory function. [source] Solvothermal fabrication of ZnO nanorods using ethanolic quantum dot precursorsPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 4 2009Yukihiro Hara Abstract ZnO nanorods were obtained by solvothermal reaction using quantum dot precursors suspended in ethanol. The ZnO suspensions were prepared from ethanolic zinc acetate solutions in the presence of lithium hydroxide, and treated by solvothermal synthesis under different reaction temperatures and duration times. Parameters of processing of these nanorods were investigated, including the concentration of precursors and solvothermal temperature. The ZnO nanorod powders were characterized by XRD, SEM, TEM, FT-IR, thermal analysis, and isothermal N2(g) adsorption analyses. Commercially available ZnO nanopowders were studied for comparison. Resulting ZnO nanorod powders were pure ZnO and showed higher surfaces area than commercial ZnO nanopowders. Length and diameter of ZnO nanorods depended on the concentration of precursors and the annealing temperature employed. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] | |||||||||||||