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81.
Developmental paths of psychological health were examined for 236 participants of the Berkeley Growth Study, the Berkeley Guidance Study, and the Oakland Growth Study. A clinician-reported aggregate index, the Psychological Health Index (PHI), based on California Q-Sort ratings, was created for subsets of participants at 14, 18, 30, 40, 50, and 62 years of age. Latent curve analysis was then used to explicate the life span development of psychological health. Psychological health development could be successfully modeled via 2 piecewise latent growth curves. Psychological health appears to be stable in adolescence and to steadily increase from 30 to 62 years of age. A moderately strong positive correlation between the 2 developmental curves indicates that those with greater psychological health in adolescence tend to show more improvement in adult psychological health also. Results illustrate the value of the PHI and the power of latent curve analysis to explicate longitudinal stability and change. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
82.
Fernandez AT Gammelmark KL Dahl JJ Keen CG Gauss RC Trahey GE 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2003,50(1):40-57
Ultrasound imaging can be improved with higher order arrays through elevation dynamic focusing in future, higher channel count systems. However, modifications to current system hardware could yield increased imaging depth-of-field with 1.75D arrays (arrays with individually addressable elements, several rows in elevation) through the use of synthetic elevation imaging. We describe synthetic elevation beamforming methods and its implementation with our 8 /spl times/ 128, 1.75D array (Tetrad Co., Englewood, CO). This array has been successfully interfaced with a Siemens Elegra scanner for summed RF and single channel RF data acquisition. Individual rows of the 8 /spl times/ 128 array can be controlled, allowing for different aperture configurations on transmit and receive beamforming. Advantages of using this array include finer elevation sampling, a larger array footprint for aberration measurements, and elevation focusing. We discuss system tradeoffs that occur in implementing synthetic receive and synthetic transmit/receive elevation focusing and show significant image quality improvements in simulation and phantom data results. 相似文献
83.
Dams R Murphy CM Choo RE Lambert WE De Leenheer AP Huestis MA 《Analytical chemistry》2003,75(4):798-804
A quantitative LC-APCI-MS/MS method for simultaneous determination of multiple illicit drugs, methadone, and their metabolites in oral fluid was developed and validated. Sample pretreatment was limited to acetonitrile protein precipitation. LC separation was performed in 25.5 min, with a total analysis time of 35 min. Identification and quantitation were based on selected reaction monitoring. Calibration by linear regression analysis utilized deuterated internal standards and a weighing factor 1/x. Limits of detection and lower limits of quantitation (LOQ) were established between 0.25 and 5 ng/ mL and 0.5-10 ng/mL, respectively. linearity was obtained with an average correlation coefficient (R2) of >0.99, over a dynamic range from the LOQ up to maximum 500 ng/mL The method demonstrated good accuracy, intra- and interbatch precision, recovery, and stability for all compounds. No oral fluid matrix effect was observed throughout the chromatographic run. Protein precipitation provided a fast and simple sample pretreatment, while LC-APCI-MS/MS proved to be a sensitive and rugged quantitative method for multiple illicit and legal drugs in oral fluid. The method proved to be suitable for the evaluation of oral fluid as an alternative matrix to urine for monitoring illicit drug use and for determining oral fluid methadone concentrations in pregnant opiate and/or cocaine addicts. 相似文献
84.
Sullivan C Mitchelmore CL Hale RC Van Veld PA 《The Science of the total environment》2007,384(1-3):221-228
Biosolids (treated sewage sludge) are increasingly disposed of on land. Thus particle-sorbed and dissolved constituents have the potential to enter nearby watersheds. Although organic contaminants are known to be present in biosolids these are not currently regulated and little data exist on their potential toxicity to aquatic organisms. We exposed Pimephales promelas to two concentrations of biosolids (0.5 and 2.5 g l(-1)) for 28-days (static-renewal) and characterized contaminants present and the extent of CYP1A and DNA damage induction at various time points. Many organic contaminants were detected in the biosolids, with polycyclic aromatic hydrocarbons (PAHs) being the dominant class. Substantial levels of polybrominated diphenyl ethers (PBDEs) and nonylphenols (NPs) were also present. Significant induction of hepatic CYP1A protein compared with controls (P<0.05) was observed in both low (0.5 g l(-1)) and high (2.5 g l(-1)) exposed fish from Day 7. CYP1A levels peaked at Day 21 with 21-fold and 8-fold inductions over controls in high and low dose fish respectively. Induction of DNA damage in hepatocytes (single strand breaks as measured using the COMET assay) was observed in both exposures compared with controls on Days 14 and 28 (P<0.05). A significant correlation was found between CYP1A induction and DNA damage (Pearson correlation index, P<0.05). It is plausible that activation of PAHs may be responsible for the induction of CYP1A and resulting increase in DNA damage. Our data show the potential for detrimental effects in the event of exposure of aquatic organisms to biosolids and the need for further investigations of possible impacts due to constituents not covered by current guidelines. 相似文献
85.
Addresses 2 ethical issues in the use of human Ss in research: (1) the effects of participation in deception and obedience research on "character" and socially relevant behavior and (2) required participation of students as Ss. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
Jeffery CJ 《Mass spectrometry reviews》2005,24(6):772-782
Mass spectrometry has become one of the most important techniques in proteomics because of its use to identify the proteins found in different cell types, organelles, and multiprotein complexes. This information about protein location and binding partners can provide valuable clues to infer a protein's function. However, more and more proteins are found that "moonlight," or have more than one function, and the presence of moonlighting proteins can make more difficult the identification of protein function in those studies. This review discusses examples of moonlighting proteins and how their presence can affect the results of mass spectrometry studies that identify the locations, levels, and changes in protein expression. Although the presence of moonlighting proteins can complicate the results of those studies, mass spectrometry-derived protein-expression profiles potentially provides a very powerful method to find additional moonlighting proteins because they do not require a prior hypothesis of the protein's function. 相似文献
87.
88.
Gregg Caldwell Eberhard W. Neuse Constance E. J. van Rensburg 《Journal of Inorganic and Organometallic Polymers》1997,7(4):217-231
Several polymer-platinum conjugates comprising the square-planar cis-diaminedichloroplatinum(II) complex system of cisplatin-type anticancer drugs are screened for antiproliferative activity in cell culture tests. The water-soluble conjugates prepared in this study or taken from preceding investigations are obtained by platination of aliphatic polyamide carriers containing ethylenediamine segments as side-group or main-chain components. These segments, coordinating to the metal as cis-diamine chelating ligands, are bound to, or into, the carrier backbone through biofissionable amide links permitting drug release from the carrier. In vitro tests are performed against a HeLa human cervix carcinoma cell line. IC50 data, expressed as the concentration of Pt in the conjugates (g/ml), causing 50% inhibition of cell growth, show the highest activity, with IC50=14 g/ml, to be associated with a conjugate derived from a polyaspartamide carrier that contains the platinum complex as a side group in proximity to the main chain and, additionally, contains dimethylaminopropyl side groups as solubilizing functions. At the low end of the performance spectrum is a conjugate, with IC50>120 g/ml, possessing a similar backbone and metal-binding structure, yet comprising long poly(ethylene oxide) grafts. The latter apparently shield the complex-binding tether from enzymatic attack and thus prevent efficient intracellular release of the monomeric complex. Selected conjugates will be submitted for toxicological evaluation. 相似文献
89.
对工程设计的实证研究指出了提高解决方案质量的步骤特征:机会策略;用脑思考和用手思考(画草图)相结合;对自己的成果进行提问式反思。这些步骤特征符合工作活动的思维调控理论的预测(“行为理论”)。 相似文献
90.
James C. Hower Constance L. Senior Eric M. Suuberg Robert H. Hurt Jennifer L. Wilcox Edwin S. Olson 《Progress in Energy and Combustion Science》2010
The control of mercury in the air emissions from coal-fired power plants is an ongoing challenge. The native unburned carbons in fly ash can capture varying amounts of Hg depending upon the temperature and composition of the flue gas at the air pollution control device, with Hg capture increasing with a decrease in temperature; the amount of carbon in the fly ash, with Hg capture increasing with an increase in carbon; and the form of the carbon and the consequent surface area of the carbon, with Hg capture increasing with an increase in surface area. The latter is influenced by the rank of the feed coal, with carbons derived from the combustion of low-rank coals having a greater surface area than carbons from bituminous- and anthracite-rank coals. 相似文献