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991.
Justice Laura M.; Bowles Ryan P.; Pence Turnbull Khara L.; Skibbe Lori E. 《Canadian Metallurgical Quarterly》2009,45(2):460
This study tested the hypotheses that (a) persistent language difficulties during childhood would predict lower school readiness and (b) language difficulties present just prior to school entry would predict lower school readiness beyond any effects of persistence. The study involved examining indicators of school readiness collected at kindergarten for children exhibiting various histories of language ability based on language measures collected at 15, 24, 36, and 54 months by the National Institute of Child Health and Human Development's Early Child Care Research Network. Children (N = 1,064) were classified according to whether they exhibited expressive or receptive language difficulties at each time point measured. The relation between persistence and timing of these difficulties to each kindergarten outcome was studied through a common factor approach for categorical outcomes. Persistence of language difficulties was not generally related to kindergarten outcomes. However, a robust effect was found for timing of language difficulties: Children who exhibited language difficulties at 54 months exhibited significantly depressed performance on measures of school readiness. Findings are discussed in terms of current policy and research concerning kindergarten readiness for children exhibiting risk. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
The potential association between psychosis and violence to others has long been debated. Past research findings are mixed and appear to depend on numerous potential moderators. As such, the authors conducted a quantitative review (meta-analysis) of research on the association between psychosis and violence. A total of 885 effect sizes (odds ratios) were calculated or estimated from 204 studies on the basis of 166 independent data sets. The central tendency (median) of the effect sizes indicated that psychosis was significantly associated with a 49%–68% increase in the odds of violence. However, there was substantial dispersion among effect sizes. Moderation analyses indicated that the dispersion was attributable in part to methodological factors, such as study design (e.g., community vs. institutional samples), definition and measurement of psychosis (e.g., diagnostic vs. symptom-level measurement, type of symptom), and comparison group (e.g., psychosis compared with externalizing vs. internalizing vs. no mental disorder). The authors discuss these findings in light of potential causal models of the association between psychosis and violence, the role of psychosis in violence risk assessment and management, and recommendations for future research. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
Xiuhong Zhao Laura Drumm Ke Yin Karl J. Rockne 《Canadian Metallurgical Quarterly》2009,135(5):291-298
Semivolatile hydrophobic organic contaminants (SV-HOCs) in sediments are a growing problem. Previous research in our laboratory has demonstrated that cleanup of the entire sediment may not be necessary due to sequestration of the majority of SV-HOCs like polycyclic aromatic hydrocarbons (PAHs) into the low density fraction that we hypothesize is separable from the bulk sediment hydraulically. In our current study, PAH-contaminated sediments from the Indiana Harbor Canal were hydraulically dredged and impounded in a stilling basin by the U.S. Army Corp of Engineers to evaluate a hydraulic dredge and characterize water treatment needs. This project provided an opportunity to test our hypothesis that a segregation of SV-HOC contaminated sediments would occur via hydraulic settling processes in the stilling basin at field scale. Following decommission of the basin, sediment cores were collected along transects from the basin influent immediately after removal of the overlying water, sectioned and characterized for physical and chemical parameters. As hypothesized, sediments showed large decreases in bulk density with increasing distance from the basin inlet. PAH concentrations increased up to 40-fold (120–4,900?mg?kg?1) and were highly correlated with the fraction of low density material in the sediment. Our results provide evidence that hydraulic dredging can result in a separation of highly contaminated sediment with high amounts of low density material from bulk sediment. This outcome may be either fortuitous or detrimental depending on the ultimate means of disposal. If subsequent dewatering occurs (such as in a confined disposal facility), prediction of PAH volatilization flux needs to be based on the in situ surface concentration which can be very high due to slow settling low density particles. Conversely, if the goal is beneficial reuse, higher density sediment with relatively low PAH levels near the inlet may be readily collected. 相似文献
994.
Kubzansky Laura D.; Koenen Karestan C.; Jones Cynthia; Eaton William W. 《Canadian Metallurgical Quarterly》2009,28(1):125
Objective: Posttraumatic stress disorder (PTSD) reflects a prolonged stress reaction and dysregulation of the stress response system and is hypothesized to increase risk of developing coronary heart disease (CHD). No study has tested this hypothesis in women even though PTSD is more prevalent among women than men. This study aims to examine whether higher levels of PTSD symptoms are associated with increased risk of incident CHD among women. Design: A prospective study using data from women participating in the Baltimore cohort of the Epidemiologic Catchment Area study (n = 1059). Past year trauma and associated PTSD symptoms were assessed using the NIMH Diagnostic Interview Schedule. Main Outcome Measures: Incident CHD occurring during the 14-year follow-up through 1996. Results: Women with five or more symptoms were at over three times the risk of incident CHD compared with those with no symptoms (age-adjusted OR = 3.21, 95% CI: 1.29-7.98). Findings were maintained after controlling for standard coronary risk factors as well as depression or trait anxiety. Conclusion: PTSD symptoms may have damaging effects on physical health for civilian community-dwelling women, with high levels of PTSD symptoms associated with increased risk of CHD-related morbidity and mortality. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
The purpose of the current study was to explore how mother’s and father’s connectedness and involvement individually and collectively influence the lives of their children. Specifically, we asked how fathers’ and mothers’ parent–child connectedness and behavioral involvement influenced both problem behaviors (externalizing and internalizing behaviors) and positive outcomes (prosocial behaviors and hope) during early adolescence. Data for this study were taken from the Flourishing Families Project, from which 349 mothers and fathers were selected, along with their early adolescent child (mean age = 11.23 years, SD = .96). Hierarchical regression analyses revealed (even after controlling for child age, gender, and self-regulation) that mothers’ and fathers’ contributions differed, primarily as a function of child outcome. Namely, father (but not mother) connectedness and involvement were negatively related to adolescents’ internalizing and externalizing behaviors, whereas mother (but not father) connectedness and involvement were positively related to adolescents’ prosocial behaviors and hope. We also found that when one parent’s involvement was low (for whatever reason), the other parent’s involvement made a significant and important contribution to the child’s well-being, particularly in the area of internalizing behaviors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
Tonino Caruso Marta Feroci Achille Inesi Monica Orsini Arrigo Scettri Laura Palombi 《Advanced Synthesis \u0026amp; Catalysis》2006,348(14):1942-1947
Solvent‐ and supporting electrolyte‐free electrolysis in a two‐compartment cell proved to be effective for the direct electroactivation of C H acid‐containing compounds vs. catalytic addition processes. Michael adducts (including quaternary carbon centres) and 2‐nitroalkanols were obtained in very good yields and selectivity on application of a catalytic amount of electricity under galvanostatic conditions. 相似文献
997.
Microbial inactivation by pulsed electric fields in a batch treatment chamber: effects of some electrical parameters and food constituents 总被引:1,自引:0,他引:1
Pilar Maas Laura Barsotti J. Claude Cheftel 《Innovative Food Science and Emerging Technologies》2001,2(4):239-249
The inactivation of Escherichia coli by high voltage pulsed electric fields in a batch treatment chamber was studied in liquid, solid and semisolid foods or model systems. Treatment heterogeneity was demonstrated and found to be due to the presence of an air bubble trapped inside the chamber. Agitation of the inoculated liquid samples (16 mM sodium phosphate buffer, pH 7, ρ=460 Ωcm) during pulse processing resulted in efficient microbial inactivation (five log cycles at 33 kV/cm and 25°C after 261 μs of cumulated pulses). A slower inactivation rate was observed in inoculated solid agar gels of the same pH and resistivity, under the same pulse processing conditions. The inactivation of E. coli in inoculated dairy cream (33% fat, pH 6.8, ρ=370 Ωcm), ovalbumin solution (10% protein w/v, pH 6.7, ρ=370 Ωcm) or fish egg suspension (pH 6.8, ρ=400 Ωcm) was almost identical to that in 16 mM phosphate buffer, pH 7. Thus emulsified lipids, soluble proteins or conductive food particulates do not appear to protect against microbial inactivation by electric pulses. 相似文献
998.
Landscape ecological planning process for wetland, waterfowl, and farmland conservation 总被引:1,自引:0,他引:1
A landscape ecological planning process (LEP process) is described that addresses the issues of rice production and wetland habitat conservation on privately owned rice farms in Texas. The LEP process was used to evaluate proposed land-use management plans based on alternative policies for the next US Farm Bill, which would be in effect from 2003 to 2009. A system simulation model, geographic information systems (GIS) model based on expert knowledge, as well as expert opinion, were used to evaluate uncertainty about the effects of these plans and policies on different types of farms and the quality of winter habitat of lesser snow geese. The models simulated shifts in land-use, rice and cattle production, farm profitability, and use of habitat by geese. Simulation results suggested that the level of federal subsidies for all policies influenced the continuation of rice production from 2003 to 2009. In addition, the size of the farm influenced whether rice production continued until 2009. The smaller farms were more sensitive to decreases in federal subsidies than larger farms because smaller farms received less income from goose hunting leases. Winter habitat for lesser snow geese was reduced in terms of patch size and nearest neighbor distance when rice production was discontinued by 2009 for all policies. Agricultural policy experts, who were familiar with the study sites, selected the modified version of the conservation policy as the example that would most benefit farmers and geese. The experts emphasized that their policy would offer farmers more flexibility to manage their farms, to diversify their incomes, and to be good land stewards. 相似文献
999.
1000.
Reinaldo Sousa Dos Santos Regla María Medina-Gali Ignacio Babiloni-Chust Laura Marroqui Angel Nadal 《International journal of molecular sciences》2022,23(9)
There is a need to develop identification tests for Metabolism Disrupting Chemicals (MDCs) with diabetogenic activity. Here we used the human EndoC-βH1 β-cell line, the rat β-cell line INS-1E and dispersed mouse islet cells to assess the effects of endocrine disruptors on cell viability and glucose-stimulated insulin secretion (GSIS). We tested six chemicals at concentrations within human exposure (from 0.1 pM to 1 µM). Bisphenol-A (BPA) and tributyltin (TBT) were used as controls while four other chemicals, namely perfluorooctanoic acid (PFOA), triphenylphosphate (TPP), triclosan (TCS) and dichlorodiphenyldichloroethylene (DDE), were used as “unknowns”. Regarding cell viability, BPA and TBT increased cell death as previously observed. Their mode of action involved the activation of estrogen receptors and PPARγ, respectively. ROS production was a consistent key event in BPA-and TBT-treated cells. None of the other MDCs tested modified viability or ROS production. Concerning GSIS, TBT increased insulin secretion while BPA produced no effects. PFOA decreased GSIS, suggesting that this chemical could be a “new” diabetogenic agent. Our results indicate that the EndoC-βH1 cell line is a suitable human β-cell model for testing diabetogenic MDCs. Optimization of the test methods proposed here could be incorporated into a set of protocols for the identification of MDCs. 相似文献