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81.
Wetter David W.; Carmack Cindy L.; Anderson Cheryl B.; Moore Constance A.; De Moor Carl A.; Cinciripini Paul M.; Hirshkowitz Max 《Canadian Metallurgical Quarterly》2000,8(1):88
A past history of depression is associated with a decreased likelihood of quitting smoking. Tobacco withdrawal may be a mechanism through which depression history impedes smoking cessation. This research examined the influence of depression history on unmedicated tobacco withdrawal signs (polysomnographic measures of sleep) and symptoms (self-reported urge, negative affect, hunger, and sleep) among women (N/& =/&13). Depression history was associated with differential withdrawal-induced changes in several REM sleep parameters. Self-report and other polysomnography (sleep fragmentation, slow-wave sleep) measures displayed statistically significant withdrawal effects but did not discriminate between depression history groups. These results suggest that REM sleep parameters may be sensitive to differential tobacco withdrawal responses that are not readily apparent through self-reported symptoms. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
82.
Anderson Cheryl B.; Hughes Sheryl O.; Fuemmeler Bernard F. 《Canadian Metallurgical Quarterly》2009,28(4):428
Objective: This study examined parent–child attitudes on value of specific types and intensities of physical activity, which may explain gender differences in child activity, and evaluated physical activity as a mechanism to reduce time spent in sedentary behaviors. Design: A community sample of 681 parents and 433 children (mean age 9.9 years) reported attitudes on importance of vigorous and moderate intensity team and individually performed sports/activities, as well as household chores. Separate structural models (LISREL 8.7) for girls and boys tested whether parental attitudes were related to child TV and computer via child attitudes, sport team participation, and physical activity, controlling for demographic factors. Main Outcome Measures: Child 7-day physical activity, sport teams, weekly TV, computer. Results: Parent–child attitude congruence was more prevalent among boys, and attitudes varied by ethnicity, parent education, and number of children. Positive parent–child attitudes for vigorous team sports were related to increased team participation and physical activity, as well as reduced TV and computer in boys and girls. Value of moderate intensity household chores, such as cleaning house and doing laundry, was related to decreased team participation and increased TV in boys. Only organized team sports, not general physical activity, was related to reduced TV and computer. Conclusion: Results support parents’ role in socializing children’s achievement task values, affecting child activity by transferring specific attitudes. Value of vigorous intensity sports provided the most benefits to activity and reduction of sedentary behavior, while valuing household chores had unexpected negative effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
83.
To identify potential hormonal pheromones of the round goby (Neogobius melanostomus), a species recently introduced to the Great Lakes, we used electro-olfactogram (EOG) recording to examine olfactory responsiveness to more than 100 steroids and prostaglandins. Neogobius detected free and conjugated 18-, 19- and 21-carbon steroids, but did not detect prostaglandins. EOG cross-adaptation, used to determine if Neogobius can discriminate the detected compounds at the sensory level, suggested that the detected steroids act on four classes of olfactory receptor mechanisms named (according to the most potent ligand for each): estrone, 17 beta-estradiol-3 beta-glucuronide, etiocholanolone, and dehydroepiandrosterone-3-sulfate. Although none of the detected steroids induced reproductive behaviors, exposure to steroids from three of the four receptor classes (estrone, 17 beta-estradiol-3 beta-glucuronide, or etiocholanolone) increased ventilation rate in males, whereas only etiocholanolone increased ventilation rate in females. Using the ventilation increase as a behavioral bioassay of steroid detection, behavioral cross-adaptation studies in males demonstrated that steroids discriminated at the sensory level are also discriminated behaviorally. These findings suggest the round goby may use steroids as putative pheromones. 相似文献
84.
A leaching model was developed using the United States Geological Survey public domain PHREEQC geochemical package to simulate the leaching of Pb, Cd, As, and Cr from cementitious wastes. The model utilises both kinetic terms and equilibrium thermodynamics of key compounds and provides information on leachate and precipitate speciation. The model was able to predict the leaching of Pb, Cd, As, and Cr from cement in the presence of both simple (0.1 and 0.6M acetic acid) and complex municipal landfill leachates. Heavy metal complexation by the municipal landfill leachate was accounted for by the introduction of a monoprotic organic species into the model. The model indicated Pb and As were predominantly incorporated within the calcium silicate hydrate matrix while a greater portion of Cd was seen to exist as discrete particles in the cement pores and Cr (VI) existed mostly as free CrO4(2-) ions. Precipitation was found to be the dominant mechanism controlling heavy metal solubility with carbonate and silicate species governing the solubility of Pb and carbonate, silicate and hydroxide species governing the solubility of Cd. In the presence of acetic acid, at low pH values Pb and Cd acetate complexes were predominant whereas, at high pH values, hydroxide species dominated. At high pH values, the concentration of As in the leachate was governed by the solubility of Ca3(AsO4)2 with the presence of carbonate alkalinity competing with arsenate for Ca ions. In the presence of municipal landfill leachate, Pb and Cd organic complexes dominated the heavy metal species in solution. The reduction of As and Cr in municipal landfill leachate was crucial for determining aqueous speciation, with typical municipal landfill conditions providing the reduced forms of As and Cr. 相似文献
85.
86.
Michael Yvonne L.; Carlson Nichole E.; Bowen Deborah J.; Ritenbaugh Cheryl 《Canadian Metallurgical Quarterly》2011,30(3):375
[Correction Notice: An erratum for this article was reported in Vol 30(4) of Health Psychology (see record 2011-13978-001). The letter was missing the doi. The correct doi is 10.1037/a0022737. The online version of this article has been corrected.] Responds to the comments by J. C. Coyne and C. Johansen (see record 2011-09497-016) on the current author's original article, "Influence of stressors on breast cancer incidence in the Women's Health Initiative" (see record 2009-03297-001). Coyne and Johansen (2011) took issue with the study conducted by the current authors' group (Michael et al., 2009), which analyzed the interaction between stressful life events and social support on breast cancer risk among 83,334 postmenopausal women enrolled in the Women’s Health Initiative (WHI). While the current authors agree with the Coyne and Johansen that too often null results are difficult to publish due to confirmatory bias that privileges results that support an alternative hypothesis, they strongly disagree with the assertion that their group selectively reported findings, inaccurately reported findings, or provided selective and uncritical reference to the existing literature. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
87.
Keightley Michelle L.; Winocur Gordon; Burianova Hana; Hongwanishkul Donaya; Grady Cheryl L. 《Canadian Metallurgical Quarterly》2006,21(3):558
The authors administered social cognition tasks to younger and older adults to investigate age-related differences in social and emotional processing. Although slower, older adults were as accurate as younger adults in identifying the emotional valence (i.e., positive, negative, or neutral) of facial expressions. However, the age difference in reaction time was largest for negative faces. Older adults were significantly less accurate at identifying specific facial expressions of fear and sadness. No age differences specific to social function were found on tasks of self-reference, identifying emotional words, or theory of mind. Performance on the social tasks in older adults was independent of performance on general cognitive tasks (e.g., working memory) but was related to personality traits and emotional awareness. Older adults also showed more intercorrelations among the social tasks than did the younger adults. These findings suggest that age differences in social cognition are limited to the processing of facial emotion. Nevertheless, with age there appears to be increasing reliance on a common resource to perform social tasks, but one that is not shared with other cognitive domains. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
88.
Lori N. Ivan Benjamin R. Schmitt Kenneth A. Rose Stephen C. Riley Joan B. Rose Cheryl A. Murphy 《Journal of Great Lakes research》2018,44(6):1393-1404
Substantial natural reproduction of lake trout (Salvelinus namaycush) has not been achieved in the Great Lakes, except for Lake Superior and a few areas in Lake Huron, despite continued stocking efforts. Low thiamine levels in lake trout eggs, which can result in lethal and sublethal impacts (thiamine deficiency complex, TDC) on fry, may contribute to widespread recruitment failure in lake trout populations. We hypothesized that incorporation of sublethal impacts into dose-response curves would result in estimates of EC50s (median lethal concentrations) for fry greater than the estimates that rely only on acute mortality and that predation would exacerbate thiamine effects. To investigate the sublethal effects of TDC (prey capture success and predation mortality) on cohort growth and survival, we developed an individual-based model for lake trout fry. The model tracks daily activities, including consumption, respiration, growth, and mortality, of lake trout from hatch until fry reach a length of 33?mm when we assume fry feed naturally and thiamine effects are minimized. Model output with sublethal impacts resulted in an EC50 (7.3?nmol/g) that was greater than published studies that are limited to acute mortality (1.5?nmol/g). Furthermore, when we included interstitial and pelagic predation, the impact of sublethal effects shifted the EC50 values even higher (7.4–10?nmol/g). Simulation results indicate that low thiamine levels, in combination with moderate to high predation, can eliminate lake trout cohorts. Our simulations suggest that the sublethal effects of low thiamine can contribute to poor lake trout recruitment more than previously suspected. 相似文献
89.
Cheryl R. Dykstra William T. Route Kelly A. Williams Michael W. Meyer Rebecca L. Key 《Journal of Great Lakes research》2019,45(2):252-262
We analyzed concentrations and trends of DDE, total PCBs, and mercury in bald eagle (Haliaeetus leucocephalus) nestlings at six study areas in the upper Midwest, 2006–2015, and long-term trends at two Lake Superior sites, 1989–2015. Eaglet plasma from the Apostle Islands in Lake Superior had the highest concentrations of DDE (geometric mean [GM]?=?10.6?μg/L), and DDE concentrations decreased at 5.8% per year across the region from 2006 to 2015, and at 5.5% per year at Lake Superior sites from 1989 to 2015. Concentrations of the sum of 75 PCB congeners (ΣPCB75) were highest at Pools 3 and 4 of the Mississippi River (GM?=?114.8?μg/L) and did not decline significantly region-wide (all study areas together) between the years of 2006 and 2011. However, at Lake Superior, ΣPCB75 declined from 1995 to 2011 along the south shore at 3.6% per year, with a non-significant decline at the Apostle Islands. Concentrations of mercury in nestling breast feathers were highest at the upper St. Croix River (GM?=?6.66?μg/g wet weight). At Lake Superior study areas, mercury declined at 1.6% per year from 1991 to 2015; however, from 2006 to 2015 we found no significant trend at one of these same study areas and mercury concentrations apparently increased at two study areas. Mean concentrations of contaminants were below levels associated with significant impairment of reproduction at all sites and mean reproductive rates were?>?1.4 young per nest. However, increasing concentrations of mercury in some areas, combined with relatively high concentrations at some nests, suggest that continued monitoring of mercury should be a management priority. 相似文献
90.
Experimental thermal conditions conducive to the production of high levels of hydrogen cyanide (HCN) from flexible polyurethane foam were determined. In these experiments the material was exposed to relatively low-temperature non-flaming oxidative conditions for a short time period, during which a char was formed. Further heating of the char to temperature above 500°C generated the increased HCN levels. Upon exposure to this same two-step decomposition process, a fire-retarded flexible polyurethane foam produced twice as much char and twice as much HCN. Elemental analyses indicated that the HCN concentration was directly related to the amount of char formed and its nitrogen content. Room burns of slabs of flexible polyurethane foam and chairs containing flexible polyurethane foam indicated that this same phenomenon occurs in large-scale experiments. In these NBS tests, increased concentrations of HCN were produced when the material underwent flaming combustion following a period of smoldering, presumably from heating the char that was formed during smoldering. Investigation of the molecular mechanisms responsible for the increased HCN concentrations was attempted using ion chromatography, electron spectroscopy for chemical analysis (ESCA), Fourier transform infrared (FTIR), pyrolysis/mass spectrometry and 13C solid-state nuclear magnetic resonance (NMR) techniques. While the molecular structures of the nitrogen-containing compounds in the char were not elucidated, these analyses provided evidence of multiple compounds containing amine, amide, imine and nitrile functional groups as the most likely sources of the observed HCN. 相似文献