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1.
The surrounding environment near Dagang oil-production well suffers polycyclic aromatic hydrocarbons (PAHs) pollution. In the present study, indigenous microorganisms capable of degrading PAHs were isolated and the efficiency of PAHs removal was investigated. Seven PAH-degrading strains were isolated with the ability to grow on naphthalene, phenanthrene, pyrene and fluorene. They belonged to the genus Pseudomonas, Bacillus and Rhodococcus. The strain having the highest degrading capacity for each PAH was selected by the screening test. The removal efficiency of PAHs was found to be in the order of naphthalene > fluorene > phenanthrene > pyrene. The kinetics of PAHs degradation was then followed by liquid chromatography determination and the results showed it conforms to a first-order reaction kinetic model. This study would be highly important for investigating the ability of microorganisms to utilize PAHs as growth substrates.  相似文献   

2.

Purpose

To assess health-related quality of life (HRQOL) of subjects at risk of type 2 diabetes undergoing lifestyle intervention, and predictors for improved HRQOL.

Methods

The Finnish Diabetes Risk Score was used by general practitioners to identify individuals at risk. Low-intensity interventions with an 18-month follow-up were employed. HRQOL was assessed using the SF-36 at baseline and compared with results from a general Norwegian population survey and further at 6 and 18 months. Simple and multiple linear regression analyses were applied to identify predictors of changes in HRQOL of clinical importance.

Results

Two hundred and thirteen participants (50 % women; mean age: 46 years, mean body mass index: 37) were included: 182 returned for 18-month follow-up, of whom 172 completed the HRQOL questionnaire. HRQOL was reduced with clinical significance compared with general Norwegians. The mean changes in HRQOL from the baseline to the follow-up were not of clinical importance. However, one out of three individuals achieved a moderate or large clinical improvement in HRQOL. The best determinant for improved HRQOL was obtained for a composite, clinically significant lifestyle change, i.e. both a weight reduction of at least 5 % and an improvement in exercise capacity of at least 10 %, which was associated with an improvement in five out of the eight SF-36 domains.

Conclusion

Subjects at risk of type 2 diabetes report a clinically important reduction in HRQOL compared with general Norwegians. The best predictor of improved HRQOL was a small weight loss combined with a small improvement in aerobic capacity.  相似文献   

3.
Cerium (Ce)-based compounds, such as CeO2 nanoparticles (NPs), have received much attention in the last several years due to their popular applications in industrial and commercial uses. Understanding the impact of CeO2 NPs on nutrient cycles, a subchronic toxicity study of CeO2 NPs on soil-denitrification process was performed as a function of particle size (33 and 78 nm), total Ce concentration (50–500 mg L?1), and speciation [Ce(IV) vs. Ce(III)]. The antimicrobial effect on the soil-denitrification process was evaluated in both steady-state and zero-order kinetic models to assess particle- and chemical-species specific toxicity. It was found that soluble Ce(III) was far more toxic than Ce(IV)O2 NPs when an equal total concentration of Ce was evaluated. Particle size-dependent toxicity, species-dependent toxicity, and concentration-dependent toxicity were all observed in this study for both the steady-state and the kinetic evaluations. Changes in physicochemical properties of Ce(IV)O2 NPs might be important in assessing the environmental fate and toxicity of NPs in aquatic and terrestrial environments.  相似文献   

4.

Purpose

The distress thermometer (DT) is commonly used in cancer care to improve detection of distress. The DT’s recommended cut-off score of 4 or 5 has typically been established using the Hospital Anxiety and Depression Scale (HADS) by receiver operating characteristic curve analysis. The present analysis complements these studies by critically examining the use of the HADS to identify the DT’s cut-off score and corroborating the DT’s cut-off scores using item response theory (Rasch analysis).

Methods

The DT and HADS were completed by 340 patients with cancer. Rasch dimensionality analysis was performed on the HADS-Total, and test characteristic curves were examined to equate the DT and the HADS subscales. Identified DT cut-off scores were then examined for their sensitivity and specificity.

Results

Rasch analysis did not support the unidimensionality of HADS-Total. The test characteristic curves indicated that a cut-off score of ≥8 on the HADS-Anxiety and HADS-Depression subscales was equivalent to a score of 6 and 7 on the DT, respectively. However, a DT cut-off score of 5 resulted in the best balance between sensitivity and specificity across the HADS-Anxiety and HADS-Depression subscales.

Conclusions

Despite being a popular practice, the present findings did not support combining the HADS-Anxiety and HADS-Depression subscales to identify the DT’s cut-off score. Furthermore, these results inform the use of the DT as a preliminary screening tool and suggest that when a single screen is used, a DT cut-off score of 6 or 7 might be more appropriate than the typical cut-off score of 4.  相似文献   

5.
American Indians and Alaska Natives serve at the highest rate of any US race or ethnic group, yet are the most underserved population of Veterans and do not take advantage of the Department of Veterans Affairs (VA) benefits and services. Barriers to seeking care include stigma, especially for mental health issues; distance to care; and lack of awareness of benefits and services they are entitled to receive. In response to this underutilization of the VA, an innovative program—the Tribal Veterans Representative (TVR) program—was developed within the VA to work with American Indians and Alaska Natives in rural and remote areas. The TVR goes through extensive training every year; is a volunteer, a Veteran and tribal community member who seeks out unenrolled Native Veterans, provides them with information on VA health care services and benefits, and assists them with enrollment paperwork. Being from the community they serve, these outreach workers are able to develop relationships and build rapport and trust with fellow Veterans. In place for over a decade in Montana, this program has enrolled a countless number of Veterans, benefiting not only the individual, but their family and the community as well. Also resulting from this program, are the implementation of Telemental Health Clinics treating Veterans with PTSD, a transportation program helping Veterans get to and from distant VA facilities, a Veteran Resource Center, and a Veteran Tribal Clinic. This program has successfully trained over 800 TVRs, expanded to other parts of the country and into remote areas of Alaska.  相似文献   

6.
This study reported the distribution of polycyclic aromatic hydrocarbons (PAHs) concentrations simultaneously obtained in gas/rain/particle in rain event from 2010 to 2012 in Osaka, Japan. A sampling method for rain and the materials of a rain collector were also surveyed. Benzene and a glass bottle were used to prevent the decrease of PAHs in rainwater. The average concentration of Σ9PAHs in rainwater ranged between 17.49 and 646.52 ng dm?3. The mean ratio of these Σ9PAHs in gas versus particles was 77.9 and 68.3 % during rain and no rain, respectively. During rain, the PAHs in particles were scavenged by rain and were incorporated via washout by collision with each other. Therefore, the ratio of PAHs in rainwater was similar to that in particles. The low molecular weight LMW-PAHs from gas were recognized as being dissolved in rain but did not affect the ratio of PAHs in rain. Four rings PAH were dominant in gas/rain/particles. The seasonal variation of Σ9PAHs in rainwater was reported and discussed, and the PAHs levels during the winter and spring were higher compared with that of summer and autumn. Furthermore, the sampling method of PAHs in snow is also developed.  相似文献   

7.

Purpose

To assess how vitamin D status is associated with health-related quality of life (HRQOL) among older residents of Canada.

Design

We analysed baseline data of 1,493 Canadians aged 50 years and over in Alberta on HRQOL (EQ-5D-5L) and serum 25-hydroxyvitamin D (25(OH)D) as a measure of vitamin D status. We applied multivariable regression methods to examine the association between vitamin D status and each of the five dimensions and the summary index of the EQ-5D-5L.

Results

Participants with higher serum 25(OH)D levels were significantly less likely to report problems with mobility, usual activities, and depression and anxiety. Specifically, age- and gender-adjusted odds ratios for reporting problems with mobility, usual activities, and depression and anxiety were 0.58 (95 % confidence interval 0.44–0.78), 0.67 (0.50–0.89), and 0.67 (0.51–0.88) per 100 nmol/L increase in 25(OH)D, respectively. No significant associations were observed for problems with self-care and with pain and discomfort. HRQOL scores combining the responses of each of the five dimensions increased significantly with increasing serum 25(OH)D levels.

Conclusions

This is the first study to reveal the importance of vitamin D for the five dimensions of HRQOL in a community-based sample. The observed associations of vitamin D and HRQOL call for intervention studies to strengthen the evidence of the potential benefits of vitamin D supplementation for HRQOL among older adults.  相似文献   

8.

Purpose

Polycyclic aromatic hydrocarbons (PAHs) are multiple compounds that include many carcinogens. We conducted a cross-sectional study in steel plant workers in Anshan, China, to identify biomarkers that reflect the carcinogenicity of PAHs.

Methods

Subjects were 57 workers and 20 controls. Level of personal exposure to PAHs was measured using GC–MS. In accordance with the assessment methods defined by the United States Environmental Protection Agency (US EPA), 15 PAHs were selected for the analysis. For the measurement of urinary metabolites, urine samples were treated with β-glucuronidase and analyzed using HPLC with a fluorescence detector.

Results

The mean range of personal exposure to 15 PAHs (total PAHs) was 178.85, 47.08–1,329.45 (geometric mean, 5th and 95th percentile) μg/m3. Ten known urinary metabolites (1-hydroxynaphthalene, 2-hydroxynaphthalene, 2-hydroxyfluorene, 1-hydroxyphenanthrene, 3-hydroxyphenanthrene, 9-hydroxyphenanthrene, 1-hydroxypyrene, 3-hydroxybenz[a]anthracene, 6-hydroxychrysene, and 3-hydroxybenzo[a]pyrene) and four unknown peaks were detected. The highest correlation was between total PAHs and urinary 2-hydroxynaphthalene (Spearman r = 0.716, P < 0.01). Among the detected urinary metabolites, 2-hydroxyfluorene, 1-hydroxyphenanthrene, 3-hydroxyphenanthrene, and 1-hydroxypyrene were found to correlate significantly with the “Σ carcinogenic potency of PAHs” (sum of seven carcinogenic PAHs calculated from the levels of personal PAHs and relative potency factors), and with the greatest correlation found for 1-hydroxypyrene (Spearman r = 0.630, P < 0.01).

Conclusions

The analysis of personal exposure to 15 PAHs and 10 urinary metabolites, and calculation of Σ carcinogenic potency, indicated that urinary 1-hydroxypyrene was the most comprehensive carcinogenic biomarker of exposure to PAHs.  相似文献   

9.
To inform risk assessment and regulatory decision-making, the relationship between 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and prostate cancer requires clarification. This article systematically and critically reviews the epidemiologic evidence on the association between exposure to TCDD or Agent Orange, a TCDD-contaminated herbicide used during the Vietnam War, and prostate cancer risk. Articles evaluated include 11 studies of three cohorts, four case–control or cross-sectional studies, and three case-only studies of military veterans with information on estimated Agent Orange or TCDD exposure; 13 studies of seven cohorts, one case–control study, and eight proportionate morbidity or mortality studies of Vietnam veterans without information on Agent Orange exposure; 11 cohort studies of workers with occupational exposure to TCDD; and two studies of one community cohort with environmental exposure to TCDD. The most informative studies, including those of Vietnam veterans involved in Agent Orange spraying or other handling, herbicide manufacturing or spraying workers with occupational TCDD exposure, and community members exposed to TCDD through an industrial accident, consistently reported no significant increase in prostate cancer incidence or mortality. Only some potentially confounded studies of Vietnam veterans compared with the general population, studies with unreliable estimates of Agent Orange exposure, and analyses of selected subgroups of Vietnam veterans reported positive associations. Overall, epidemiologic research offers no consistent or convincing evidence of a causal relationship between exposure to Agent Orange or TCDD and prostate cancer. More accurate exposure assessment is needed in large epidemiologic studies to rule out a causal association more conclusively.  相似文献   

10.
The physicochemical property of standard test media significantly influenced the aggregation and dissolution of Ag, CuO and ZnO nanoparticles (NPs) and the toxicity of the NPs to Daphnia magna. For all the NPs, the highest amount of metal ions was released from the ISO medium, whereas acute toxicity to D. magna was highest in the moderately hard water medium (EC50 = 4.94, 980, and 1,950 μg L?1 for Ag, CuO, and ZnO, respectively). By comparing EC50 values based on the total and dissolved concentrations of NPs with those of metal salt solutions, we found that both particulate and dissolved fractions were likely responsible for the toxicity of Ag NPs, whereas the dissolved fraction mostly contributed to the toxicity of CuO and ZnO NPs.  相似文献   

11.

Purpose

There is substantial interest in testing interventions for improving quality of life (QOL) and health-related quality of life (HRQOL) in people with multiple sclerosis (MS). Yet, there is limited research on the psychometric properties of QOL [e.g., Satisfaction with Life Scale (SWLS), Leeds MS Quality of Life Scale (LMSQOL)] and HRQOL [e.g., Short Form 12 Health Survey (SF-12) and Multiple Sclerosis Impact Scale-29 (MSIS-29)] measures in this population. Such research is important for designing and interpreting interventions. We examined the test–retest reliability, measurement error, and interpretability of QOL (i.e., SWLS and LMSQOL) and HRQOL (i.e., SF-12 and MSIS-29) measures over 6 months in people with MS.

Methods

Individuals with MS (n = 274) completed the SWLS, LMSQOL, SF-12 and MSIS-29 on two occasions, 6 months apart. We estimated test–retest reliability [intraclass correlation coefficient (ICC)], measurement error [standard error of measurement (SEM) and coefficient of variation] and interpretability [smallest detectable change (SDC)].

Results

Intraclass correlation coefficient values ranged between moderate and good (ICC range = 0.669–0.883); the MSIS-29 physical component had the best reliability, and the SF-12 mental component had the worst reliability. Measurement error, based on percent SEM, varied among measures; the physical and mental components of the SF-12 (%SEM = 4.6 and 5.3, respectively) had the best measurement error, and the MSIS-29 mental component (%SEM = 13.2) and the SWLS (%SEM = 12.7) had the worst measurement error. Interpretability, based on percent SDC, varied among measures; interpretability was best for the physical and mental components of the SF-12 (%SDC = 12.7 and 14.7, respectively) and worst for the MSIS-29 mental component (%SDC = 36.7) and the SWLS (%SDC = 35).

Conclusion

We provide novel data for helping researchers and clinicians select and interpret QOL and HRQOL measures and scores for interventions among people with MS. Such information will better inform our understanding of intervention effectiveness.  相似文献   

12.
Similar temporal declines in infantile hypertrophic pyloric stenosis (IHPS) and sudden infant death syndrome (SIDS) and other common features have led to hypotheses about a shared etiology. We carried out a population-based study to highlight similarities and differences between IHPS and SIDS. We used vital statistics and hospitalization data on all live births in Washington State, USA (1987–2009). Changes in IHPS and SIDS rates over time were quantified using rate ratios with 95 % confidence intervals (CI). The duration between birth and diagnosis of IHPS or SIDS was examined as a function of gestational age at birth. Logistic regression analysis was used to identify risk factors and quantify adjusted temporal trends (2000–2008). Although both IHPS and SIDS rates declined significantly between 1987 and 2008, the patterns and magnitude of the declines (40 and 74 %, respectively) were different. IHPS and SIDS shared risk factors such as maternal smoking and single parent status but other factors showed qualitatively or and quantitatively different associations. Primiparity was a risk factor for IHPS [odds ratio (OR) 1.24, 95 % CI 1.09–1.41], and a protective factor for SIDS (OR 0.44, 95 % CI 0.36–0.55), while male sex had a stronger association with IHPS (OR 4.51, 95 % CI 3.85–5.28 vs 1.36, 95 % CI 1.13–1.64). Both IHPS and SIDS showed significant inverse associations between gestational age at birth and chronologic age at diagnosis/death. IHPS and SIDS share some epidemiologic features and risk factors but other risk factors have qualitatively or quantitatively different effects and recent temporal trends in the two diseases are dissimilar.  相似文献   

13.
Arsenic is a groundwater contaminant of global concern. It is a potent human carcinogen, and its marked genotoxic effects have been reported in several human and animal studies. The present work investigates the applicability of the random amplified polymorphic DNA (RAPD) assay to study the DNA-damaging effects of arsenic at low-level exposure in goldfish Carassius auratus. Four experimental groups of fish, A, B, C and D, were exposed to 0, 10, 50, and 1,000 µg L?1 of arsenic, respectively, in aquaria water for 15 consecutive days. Genomic DNA extraction was followed by RAPD–polymerase chain reaction amplification for each fish separately. One arbitrary decamer primer (PUZ-19) of 33 primers used appeared as the most informative and was capable of exhibiting marked alterations in RAPD profiles between arsenic-exposed and unexposed (control) samples. Different sets of 11 loci were amplified in various experimental groups with four clear polymorphic bands by the primer PUZ-19. The X and XIII amplification loci, which were prominent in the unexposed group, failed to appear in the arsenic-exposed groups. In contrast, the I and XI RAPD bands appeared as new amplification loci in all of the exposed groups. Such alterations in genomic DNA, however, did not exhibit a clear dose-dependent tendency. The RAPD assay, because of its efficacy to unmask alterations in genomic DNA induced by arsenic at low exposure level of 10 µg L?1, appears to be a sensitive and potential tool for detecting arsenic genotoxicity.  相似文献   

14.

Purpose

Many maintenance hemodialysis patients do not feel well after the hemodialysis session and need a time to recover. The main objective of the study was to investigate whether a simple question about the need of some time to recover from hemodialysis was associated with scores of comprehensive tools of depression symptoms and health-related quality of life (HRQOL).

Methods

Cross-sectional evaluation of 800 Brazilian patients enrolled in the Prospective Study of the Prognosis of Chronic Hemodialysis Patients (PROHEMO). The KDQOL-SF was used for HRQOL and the 20-item CES-D and BDI for depression symptoms. Linear and logistic models were used for multivariable adjustments.

Results

Patients who reported some time to recover (30 %) had significantly (P < 0.001) higher depression symptoms scores (mean difference = 4.75 for CES-D and 4.48 for BDI). HRQOL scores were, in general, lower for patients who referred a time to recover, with mean differences larger than 4.0 (P < 0.05) both for physical and mental components. Strong associations of needing a time to recover and lower scores of several kidney disease-targeted HRQOL components were also observed. Differences in depression symptoms and HRQOL were largely reduced after adjustments for symptoms (muscle pain/cramps, faintness, fatigue, nausea/vomiting).

Conclusions

The results support the validity of a simple question on post-hemodialysis recovery as a proxy for scores of complex instruments for depression symptoms and HRQOL. The results suggest that the poorer HRQOL and higher depression probability in patients who need a time to recover from hemodialysis could be partially explained by the presence of hemodialysis-related symptoms.  相似文献   

15.
The objective of this work was to evaluate the ecotoxicological qualitative risk associated with the use of sewage sludge containing Zn oxide nanoparticles (ZnO-NPs) as soil amendment. A sludge-untreated soil and two sludge-treated soils were spiked with ZnO-NPs (0–1,000 mg/kg soil). Soil ecotoxicity was assessed with Eisenia fetida (acute and sublethal end points), and the unfilterable and filterable (0.02 μm) soil leachates were tested with a battery of biomarkers using Chlorella vulgaris, Daphnia magna, and the fish cell line RTG-2 (Oncorhynchus mykiss). The production of E. fetida cocoons in sludge-treated soils was lower than that in sludge-untreated soils. The highest effect in the algal growth inhibition test was detected in sludge-untreated soil, most likely caused by the loss of organic matter in these samples. The D. magna results were always negative. Toxic effects (lysosomal cell function and production of reactive oxygen species) in RTG-2 cells were only observed in sludge-treated soils. In general, the toxicity of ZnO-NPs in sludge-treated soils was similar to that of sludge-untreated soil, and the filterable leachate fraction [Zn salt (Zn2+)] did not produce greater effects than the unfilterable fraction (ZnO-NPs). Thus, after the addition of ZnO-NP—enriched sewage sludge to agricultural soil, the risk of toxic effects for soil and aquatic organisms was shown to be low. These findings are important because repeated use of organic amendments such as sewage sludge may cause more and more increased concentrations of ZnO-NPs in soils over the long-term.  相似文献   

16.

Objectives

The aim of this study was to investigate the IgE-mediated pathogenesis of severe asthma presented by a patient only after handling shiitake (Lentinus edodes) mushrooms (SM).

Material and Methods

Skin tests were performed using in-house extracts from mushrooms that the patient usually handled, i.e., shiitake, porcini, oyster and black fungus mushroom varieties. Specific IgE to champignons and various molds were determined. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) immunoblotting was performed to detect IgE-binding components. Four negative controls were included in the study.

Results

Skin prick tests performed with in-house mushroom extracts from varieties other than shiitake were completely negative, in contrast to the positive test obtained for shiitake mushrooms. Serum specific IgE levels for common molds and champignons were all negative. SDS-PAGE revealed many protein bands in the four mushroom extracts. Immunoblotting using the patient’s serum showed allergenic bands at about 15 and 24 kDa exclusively for SM that were not shared with negative controls. Another faint band was detectable at approximately 37 kDa for SM and porcini varieties.

Conclusions

Here, we present the first European case of SM-induced occupational asthma, a disease more frequently occurring in Asia. Asthma attacks stopped when the patient avoided contact with shiitake mushrooms. No skin reactions and no IgE-binding proteins by immunoblotting were detectable with the other mushrooms tested. The positive skin test with shiitake mushrooms and IgE-binding components in the shiitake extract confirmed the IgE-mediated etiology of the reaction.  相似文献   

17.

Purpose

The aim of this study was to evaluate the health-related quality of life (HRQOL) of Chinese primary care patients with lower urinary tract symptoms (LUTS).

Methods

Five hundred and nineteen primary care subjects with LUTS completed a structured questionnaire containing the International Prostate Symptom Score, the adapted Incontinence Impact Questionnaire-7, the International Consultation on Incontinence Questionnaire–Urinary Incontinence Short Form, the Chinese (HK) SF-12 Health Survey Version 2 (SF-12 v2) and the Depression, Anxiety and Stress Scale-21.

Results

LUTS patients had poorer HRQOL for the General Health and the Vitality domains and lower Physical Component Summary scores, but better HRQOL for the Role Emotion domain than the adjusted Hong Kong population norms. Clinical factors associated with poorer HRQOL measured by the SF-12 v2 included having more severe LUTS and having more severe depressive, anxiety and stress symptoms. Socio-demographic factors associated with poorer SF-12 v2 were consistent with those found in the general populations. Clinical and socio-demographic factors associated with poorer HRQOL assessed by condition-specific measures included having more severe LUTS (excluding intermittency and straining), the presence of mixed urinary incontinence, having more severe anxiety and stress symptoms, younger age, being not married, being in employment and having a lower household income.

Conclusions

LUTS had substantial negative impact on patients’ overall health perception and global well-being in Chinese population. A decline in HRQOL might be a key determinant for Chinese patients with LUTS to seek treatment. Patients with nocturia, frequency, urgency or mixed urinary incontinence and younger patients deserve more treatment attention because they appear to have poorer HRQOL.  相似文献   

18.

Purpose

To examine the general health status and health-related quality of life (HRQOL) along the diabetes continuum of middle-aged and older Finns, and to determine the glucose metabolism stage by which the HRQOL has decreased noticeably.

Methods

The cross-sectional sample consisted of 920 persons aged 51–75 from the general population in a single municipality in a rural area of Eastern Finland. Data were adjusted for age, sex, smoking history, current alcohol consumption, employment and marital status. The HRQOL and health status were evaluated using two preference-based HRQOL instruments, 15D and SF-6D, and one health profile instrument, 36-Item Short Form Health Survey (SF-36).

Results

Individuals with impaired glucose tolerance (IGT) and type 2 diabetes had noticeably low mean SF-6D, 15D and general health status. The decrease in overall HRQOL was mainly due to a decline in the physical dimensions of HRQOL. The adjusted odds ratios (95 % CI) for having noticeably low HRQOL on SF-6D, 15D and general health dimension of SF-36 associated with IGT were 1.95 (1.18–3.25), 1.35 (0.84–2.18) and 2.00 (1.21–3.29), respectively.

Conclusions

The progression along the diabetes continuum was significantly associated with a decrease in HRQOL and health status. Furthermore, the data indicate that when a person is detected to have IGT, the HRQOL and general health status have already diminished noticeably. The prevailing evidence suggests that detection and intervention before a patient develops IGT is essential in order to minimize the loss of quality of life and quality-adjusted life years.  相似文献   

19.

Purpose

The present paper assessed the validity of single-item life satisfaction measures by comparing single-item measures to the Satisfaction with Life Scale (SWLS)—a more psychometrically established measure.

Methods

Two large samples from Washington (N = 13,064) and Oregon (N = 2,277) recruited by the Behavioral Risk Factor Surveillance System and a representative German sample (N = 1,312) recruited by the Germany Socio-Economic Panel were included in the present analyses. Single-item life satisfaction measures and the SWLS were correlated with theoretically relevant variables, such as demographics, subjective health, domain satisfaction, and affect. The correlations between the two life satisfaction measures and these variables were examined to assess the construct validity of single-item life satisfaction measures.

Results

Consistent across three samples, single-item life satisfaction measures demonstrated substantial degree of criterion validity with the SWLS (zero-order r = 0.62–0.64; disattenuated r = 0.78–0.80). Patterns of statistical significance for correlations with theoretically relevant variables were the same across single-item measures and the SWLS. Single-item measures did not produce systematically different correlations compared to the SWLS (average difference = 0.001–0.005). The average absolute difference in the magnitudes of the correlations produced by single-item measures and the SWLS was very small (average absolute difference = 0.015–0.042).

Conclusions

Single-item life satisfaction measures performed very similarly compared to the multiple-item SWLS. Social scientists would get virtually identical answer to substantive questions regardless of which measure they use.  相似文献   

20.
Semen characteristics of captive American Kestrels (Falco sparverius) fed 8 ppm mirex or 33 ppm Aroclor® 1254, singly or in combination, were compared to a control group. Aroclor® 1254 produced a decline in sperm concentration but no compensatory increase in semen volume, resulting in a 22–27% decrease in sperm numbers per ejaculate. Mirex produced a marked decline in sperm concentration with a slight compensatory increase in semen volume resulting in a 70% decrease in sperm numbers. The combination of Aroclor® 1254 and mirex, at the same concentrations as fed singly, decreased sperm concentration to the same level as the Aroclor® alone with a 73% increase in semen volume, resulting in sperm numbers which did not differ from those of the controls. No effect on sperm motility was observed for any contaminant. Temporal patterns in semen characteristics differed. There was a highly significant interaction effect between Aroclor® 1254 and mirex. The excretion of mirex was increased in the presence of Aroclor® 1254, and the combination diet reduced the relative concentration of Aroclor® in the testes. The testicular mass of the PCBs + mirex group was increased. The results suggest that migratory flesheating birds feeding on a PCB- or mirex-contaminated food chain could consume enough toxicant to alter their semen quality in that breeding season, which, when coupled with altered courtship, could reduce the fertility of eggs and the reproductive fitness of the individual.  相似文献   

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