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31.
As our elderly population increases in proportion with respect to the rest of society, age-related driving impairments are increasing in importance as a public health concern. In this context, health professionals play an important role in identifying impaired drivers. This situation is complicated for two reasons: discussion of driving cessation is a sensitive topic for both health professionals and the elderly, and physicians have limited familiarity with the current American Medical Association (AMA) screening guidelines or mandated reporting laws. 相似文献
32.
The appearance of a significant amount of liberated fine pentlandite in the Raglan tailings, during a campaign to demonstrate future ore behaviour, called attention to a recovery opportunity. This opportunity was identified by a statistical benchmark survey of the operation during that campaign, and QEMSCAN measurement of these survey samples. This development was caused by escalating ore treatment rates and different characteristics in future ore sources. It was thus proposed to change the selection of collector from potassium amyl xanthate (PAX) to potassium isobutyl xanthate (PIBX). Laboratory scale flotation testwork, using high-confidence flotation testing, followed. The PIBX showed much faster flotation than the PAX. Nickel yield to first rougher concentrate was increased from 23.5% to 44.2%. The Raglan flowsheet bypasses this first rougher concentrate directly to final concentrate. Thus there was an expectation that overall performance would improve at plant scale when using PIBX. A designed plant trial was implemented in 2007 to measure and confirm the performance gain. This trial design used on–off switching following a 3-month baseline data block of normal operations using PAX. This layout provided checking of standard PAX performance prior to and during the trial. Thereafter, they were used to evaluate the trial blocks using PIBX. This trial format was deliberately designed so as to overcome the effects of autocorrelation in the operations data. In this way, small but significant metal recovery gains may be measured and proven in a plant trial. The paper describes the case study to show that this approach successfully blocks out autocorrelation in time, which is an obstacle in analysing concentrator operations data. The results showed that the PIBX had produced clear and statistically significant recovery gains for Ni, Cu, Pt and Pd. Adjusted for feed and concentrate grades, these recovery gains were: Ni: 1.04%, Cu: 1.01%, Pt: 2.67% and Pd: 1.79% in absolute terms. 相似文献
33.
Fetal alcohol syndrome (FAS) is the leading birth defect in the United States, yet few treatment options exist for children afflicted with this disorder. Although play therapy has demonstrated its efficacy with numerous special populations, as of today, no research has been conducted on its use with FAS. This article presents an overview of current data on FAS, an argument for the use of child-centered play therapy for children diagnosed FAS, and suggests areas of research needs. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
34.
35.
Lower task persistence in smokers with schizophrenia as compared to non-psychiatric control smokers.
Steinberg Marc L.; Williams Jill M.; Gandhi Kunal K.; Foulds Jonathan; Brandon Thomas H. 《Canadian Metallurgical Quarterly》2010,24(4):724
One contributing factor to difficulty in quitting smoking may be task persistence, which can be viewed as a behavioral manifestation of distress tolerance, and describes the act of persisting in a difficult or effortful task. Task persistence was assessed in smokers with schizophrenia and schizoaffective disorder (SZ/SA; N = 71) and non-psychiatric controls (N = 78) before a quit attempt. These data support the hypothesis that smokers with SZ/SA display less task persistence than do non-psychiatric controls when persistence is measured via mirror tracing and a 2-item persistence measure. Lower persistence may partially explain the reduced smoking cessation successes of smokers with SZ/SA as compared to the general population. These data also replicate findings regarding relationships between histories of ability to quit smoking and task persistence and expand them to a new population of smokers. The absence of a diagnostic status by length of previous abstinence interaction suggests that the contribution of task persistence to smoking cessation is similar for smokers with and without schizophrenia. Future studies should evaluate the ability of task persistence to predict abstinence from cigarettes prospectively among smokers with schizophrenia. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
36.
The electrode response time and the measured concentrations during dynamic catecholamine changes were compared using constant potential amperometry and fast-scan cyclic voltammetry. The amperometric response to a rectangular pulse of catecholamine is more rectangular than the cyclic voltammetric response; however, the response times are very similar when, during cyclic voltammetry, the temporal lag due to adsorption and desorption of catecholamine to the electrode is removed by deconvolution. Deconvolution of cyclic voltammetry data was applied to stimulated dopamine release in vivo, allowing for modeling of release and uptake kinetics and to measure catecholamine release from single cells, resulting in better resolution of peaks from single vesicles. In vitro postcalibrations were performed to calculate concentrations of catecholamine measured with cyclic voltammetry and amperometry. The addition of 600 microM ascorbic acid to the postcalibration buffer, allowing a catalytic reaction to regenerate dopamine, resulted in similar calculated concentrations for stimulated release of dopamine using amperometry and cyclic voltammetry. Using deconvoluted cyclic voltammetry to remove the response time lag and adding ascorbic acid to the calibration buffer, the shape and concentration of dynamic catecholamine changes are very similar when measured with constant potential amperometry and cyclic voltammetry. 相似文献
37.
Grimes Jill M.; Ricci Lesley A.; Melloni Richard H. Jr. 《Canadian Metallurgical Quarterly》2006,120(1):115
In hamsters, adolescent anabolic-androgenic steroid (AAS) exposure facilitates offensive aggression, in part by altering the development and activity of anterior hypothalamic arginine vasopressin (AH-AVP). This study assessed whether these effects were lasting by examining aggression and AH-AVP during AAS withdrawal. Adolescent hamsters administered AAS were tested as adults for aggression at 1, 4, 11, 18, or 25 days of withdrawal, sacrificed the following day, and examined for AH-AVP afferent innervation using immunohistochemistry. Through Day 12 of withdrawal, aggression and AVP were significantly higher in AAS-treated hamsters than in controls. These differences were no longer observable by Day 19 of withdrawal, at which point the behavior and neurobiology of AAS-treated hamsters reverted to that observed in controls. These data indicate that adolescent AAS exposure has short-term, reversible effects on both aggression and AH-AVP, correlating AH-AVP with the aggressive/nonaggressive behavioral phenotype during AAS withdrawal. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
38.
Xin Miao Peng Gong Sarah Swope Ruiliang Pu Raymond Carruthers Gerald L. Anderson Jill S. Heaton C.R. Tracy 《Remote sensing of environment》2006,101(3):329-341
The invasive weed yellow starthistle (Centaurea solstitialis) has infested between 4 and 6 million hectares in California. It often forms dense infestations and rapidly depletes soil moisture, preventing the establishment of other species. Precise assessment of its canopy cover, especially low-density abundance in the earlier growing season, is the key to effective management. Compact Airborne Spectrographic Imager 2 (CASI-2) hyperspectral imagery was acquired at the western edge of California's Central Valley grasslands on July 15, 2003. Four linear spectral mixture models (LSMM) were investigated from the original CASI-2 data. Band selections based upon residual analysis and feature extraction (PCA) were further explored to reduce the data dimension. All approaches, except four band-selection unconstrained LSMMs, provide consistent results. The uncertainty of the PCA-based LSMM was estimated through a Monte-Carlo simulation. The maximum standard deviation was approximately 11%. The results suggest that unmixing CASI-2 imagery could be used for estimating and mapping yellow starthistle for larger regional areas. 相似文献
39.
Jeff Olson Jeff Pan Jill Hochlowski Philip Searle Dave Blanchard 《Journal of The Association for Laboratory Automation》2002,7(4):69
Preparative Scale Supercritical Fluid Chromatography is emerging as a powerful alternative to HPLC for the purification and separation of complex chemical reaction mixtures. Advantages include greatly reduced solvent usage (and thus lower cost and environmental impact), higher throughput, and in some cases higher resolution. While there are commercially available prep SFC instruments, none currently offer all the features desired by many medicinal chemists engaged in the drug discovery process. These include: the ability to collect an unlimited number of fractions per sample with high recovery and negligible carryover, fully automated capacity to collect several hundred fractions, and the ability to collect fractions into the same disposable test tubes and racks which are already employed in HPLC. This article describes the customization of a preparatory scale SFC system purchased from Berger Instruments, Inc., Newark, DE. (a subsidiary Mettler-Toledo International, Inc., of Greifensee, Switzerland) in order to provide these capabilities. 相似文献
40.