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31.
Malnutrition, as measured by anthropometric status, is a powerful risk factor for illness and elevated death rates throughout life. Understanding the relative importance of disease, dietary quantity, and dietary quality in causing malnutrition is therefore of major importance in the design of public policy. This paper contributes to the understanding of the relative importance of quantity and quality of diet by utilizing aggregate data to complement previously reported individual-level studies. Three compilations of anthropometric data--one involving subjects from 13 provinces in China, another involving subjects from 64 counties in China, and a third involving 41 populations in 40 countries--are used to examine the relative importance for human growth of inadequacies of dietary energy and protein. The analysis involves regressing average adult heights and weights against estimates of average energy and protein availability (by province, county, or country) and per capita incomes. We use protein availability in part as a marker for overall quality of the diet, while recognizing that protein is far from perfectly correlated with dietary fat or micronutrient availability. The paper discusses issues of both data quality and statistical methodology, and points to relevant resulting caveats to our conclusions. Subject to these limitations, all three analyses suggest that, at the levels of dietary intake in these populations, lower protein intake is related to growth failure whereas lower levels of energy availability are not. The protein effect appears stronger for males than for females. 相似文献
32.
33.
Chlorination of drinking water in the presence of bromide and dissolved organic carbon (DOC) leads to the formation of brominated and chlorinated disinfection by-products (DBP). The concentration of bromide ions in the raw water is a significant factor in the speciation of DBP formed, and causes shifts in trihalomethane (THM) formation from chlorinated to brominated species. Drinking water treatment techniques that remove organic contaminants without affecting bromide ion concentrations cause increases in the brominated THM. For the present study, three water supplies containing different DOC and ambient bromide concentrations were filtered through biologically assisted granular activated carbon (BGAC). Similar to adsorption and coagulation treatment, this treatment does not remove bromide from drinking water; also, THMFP (trihalomethane formation potential) analysis indicated that the chlorinated effluent contained higher concentrations of brominated THM in comparison to the influent. Although BGAC may increase the brominated THM, which may be more toxic than the chlorinated THM, the overall reduction of THMFP by DOC removal far exceeds this negative change, thereby producing a much less toxic finished drinking water. This work is part of a study to make high DOC surface waters on the Canadian prairie safe and palatable for small volume users (individuals or small communities). 相似文献
34.
The authors examined secure base functioning in couples by studying the association between daily social support experiences and attachment security in a 14-day daily experiences study of 114 heterosexual dating couples. Both members of each couple reported on daily relationship-specific attachment security and support sought, provided, and received, as well as felt support. Within- and cross-partner associations were examined, as were reciprocal associations between support and security. Results of over-time Actor-Partner Interdependence Model analyses indicated that security (in the form of high comfort with intimacy and low anxiety about abandonment) was associated with the most adaptive support experiences, whereas high anxiety about abandonment was associated with the least, and particularly with a lack of sensitive caregiving. Implications for understanding secure base dynamics in couples are discussed and guidelines for where to intervene as well as what to target in relationship distress prevention programs are provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
35.
Searching for differences in race: Is there evidence for preferential detection of other-race faces?
Lipp Ottmar V.; Terry Deborah J.; Smith Joanne R.; Tellegen Cassandra L.; Kuebbeler Jennifer; Newey Mareka 《Canadian Metallurgical Quarterly》2009,9(3):350
Previous research has suggested that like animal and social fear-relevant stimuli, other-race faces (African American) are detected preferentially in visual search. Three experiments using Chinese or Indonesian faces as other-race faces yielded the opposite pattern of results: faster detection of same-race faces among other-race faces. This apparently inconsistent pattern of results was resolved by showing that Asian and African American faces are detected preferentially in tasks that have small stimulus sets and employ fixed target searches. Asian and African American other-race faces are found slower among Caucasian face backgrounds if larger stimulus sets are used in tasks with a variable mapping of stimulus to background or target. Thus, preferential detection of other-race faces was not found under task conditions in which preferential detection of animal and social fear-relevant stimuli is evident. Although consistent with the view that same-race faces are processed in more detail than other-race faces, the current findings suggest that other-race faces do not draw attention preferentially. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
36.
Evans SA Elliott JM Andrews LM Bartlett PN Doyle PJ Denuault G 《Analytical chemistry》2002,74(6):1322-1326
Mesoporous (H(I)-ePt) platinum microelectrodes electrodeposited from the hexagonal (H(I)) lyotropic liquid crystalline phase are shown to be excellent amperometric sensors for the detection of hydrogen peroxide over a wide range of concentrations. Good reproducibility, high precision, and accuracy of measurements are demonstrated. Mesoporous microelectrodes retain the high rates of mass transport typical of conventional microelectrodes, and their high real surface area greatly enhances their catalytic activity. This unique combination of properties overcomes the limitations of previous amperometric hydrogen peroxide sensors and yields outstanding qualitative and quantitative results. 相似文献
37.
The following study investigated wrist torque strength measurements of a group of younger and older adults. The aim of the study was to examine the impact of shape, diameter and height of lid on wrist torque opening strength. Forty participants took part in the study in four groups, younger males and females and older males and females. Data were collected for 12 test pieces. Anthropometric data were also obtained for stature, weight, hand breadth, hand length, chuck grip force, grip force, lateral grip force and pinch grip force. The analysis of the wrist torque strength measurements found that participants could exert greater force with square test pieces compared to circular test pieces of the same diameter. Examination of the circular test pieces found that as diameter and height increased, so did torque exertion data for the test pieces between 20 mm and 50 mm diameter. The surface area of the test pieces was found to be highly correlated with the level of torque exertion, thus a linear model was developed to describe this relationship. The model could be used to predict maximal torque closure levels for use in the packaging industry. The anthropometric data revealed that as height, weight, hand length and hand breadth increased, there was a correlation with the levels of torque exerted. Future research needs to further examine the relationship between surface area and torque exerted and the design of spherical lids to increase the contact area between the hand and the lid. 相似文献
38.
Assessment of QuickBird high spatial resolution imagery to detect red attack damage due to mountain pine beetle infestation 总被引:3,自引:0,他引:3
High spatial resolution remotely sensed data has the potential to complement existing forest health programs for both strategic planning over large areas, as well as for detailed and precise identification of tree crowns subject to stress and infestation. The area impacted by the current mountain pine beetle (Dendroctonus ponderosae Hopkins) outbreak in British Columbia, Canada, has increased 40-fold over the previous 5 years, with approximately 8.5 million ha of forest infested in 2005. As a result of the spatial extent and intensity of the outbreak, new technologies are being assessed to help detect, map, and monitor the damage caused by the beetle, and to inform mitigation of future beetle outbreaks. In this paper, we evaluate the capacity of high spatial resolution QuickBird multi-spectral imagery to detect mountain pine beetle red attack damage. ANOVA testing of individual spectral bands, as well as the Normalized Difference Vegetation Index (NDVI) and a ratio of red to green reflectance (Red-Green Index or RGI), indicated that the RGI was the most successful (p < 0.001) at separating non-attack crowns from red attack crowns. Based on this result, the RGI was subsequently used to develop a binary classification of red attack and non-attack pixels. The total number of QuickBird pixels classified as having red attack damage within a 50 m buffer of a known forest health survey point were compared to the number of red attack trees recorded at the time of the forest health survey. The relationship between the number of red attack pixels and observed red attack crowns was assessed using independent validation data and was found to be significant (r2 = 0.48, p < 0.001, standard error = 2.8 crowns). A comparison of the number of QuickBird pixels classified as red attack, and a broader scale index of mountain pine beetle red attack damage (Enhanced Wetness Difference Index, calculated from a time series of Landsat imagery), was significant (r2 = 0.61, p < 0.001, standard error = 1.3 crowns). These results suggest that high spatial resolution imagery, in particular QuickBird satellite imagery, has a valuable role to play in identifying tree crowns with red attack damage. This information could subsequently be used to augment existing detailed forest health surveys, calibrate synoptic estimates of red attack damage generated from overview surveys and/or coarse scale remotely sensed data, and facilitate the generation of value-added information products, such as estimates of timber volume impacts at the forest stand level. 相似文献
39.
Daley Shannon E.; Hammen Constance; Davila Joanne; Burge Dorli 《Canadian Metallurgical Quarterly》1998,66(4):595
This study examined 2 models of the relationship between personality disorder symptomatology and depression, incorporating life stress as an intervening variable. In a community sample of late adolescent women, symptoms of Cluster B disorders predicted interpersonal chronic stress and self-generated episodic stress over 2 years, controlling for initial depression. Cluster A symptoms also predicted subsequent chronic interpersonal stress, over initial depression. Cluster C pathology did not predict subsequent stress. Personality disorder symptomatology was also associated with partner reported relationship dissatisfaction. Support was found for a mediation model whereby women with higher levels of initial personality disturbance in Clusters A and B generated excessive amounts of episodic stress and interpersonal chronic stress in the next 2 years, which, in turn, increased vulnerability for depressive symptoms. A moderation model, whereby the presence of greater personality disorder symptoms would increase the likelihood of depression in response to stress, was not supported. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
40.
Green Bonnie L.; Grace Mary C.; Lindy Jacob D.; Titchener James L.; Lindy Joanne G. 《Canadian Metallurgical Quarterly》1983,51(4):573
117 individuals (mean age 37.77 yrs) who were at the fire and 30 individuals (mean age 40.72 yrs) who were not at the fire (bereaved families and rescue workers) were assessed regarding objective stressfulness of their fire experience, subjective stressfulness, and intensity of psychological symptoms (the Psychiatric Evaluation Form, PEF) in a structured clinical interview approximately 1 yr after the fire. Ss also filled out the Symptom Checklist-90, Revised Version (SCL-90R). 88 Ss were followed-up at 2 yrs. The group as a whole was more impaired than comparison samples of normals but less impaired than outpatients. Ss at the fire were less impaired than those not at the fire, who were similar to outpatients on the PEF. The latter group improved significantly on several measures from 1 to 2 yrs postfire, whereas the group at the fire showed little change. Results are discussed in the context of the specific instruments and methodology used in the present study, impairment levels of other samples, and the nature of the particular disaster. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献