Pilot Experiments with Electrodialysis and Ozonation for the Production of a Fertilizer from Urine

Pilot tests were performed with a process combination of electrodialysis and ozonation for the removal of micropollutants and the concentration of nutrients in urine. In continuous and batch experiments, maximum concentration factors up to 3.5 and 4.1 were obtained, respectively. The desalination capacity did not decrease significantly during continuous operation periods of several weeks. Membrane cleaning after 195 days resulted in approximately 35% increase in desalination rate. The Yeast Estrogen Screen (YES), a bioassay that selectively detects oestrogenic compounds, confirmed that about 90% of the oestrogenic activity was removed by electrodialysis. HPLC analysis showed that ibuprofen was removed to a high extent, while other micropollutants were below the detection limit. In view of the fact that ibuprofen is among the most rapidly transported micropollutants in electrodialysis processes, this result indicates that electrodialysis provides an effective barrier for micropollutants. Standardised plant growth tests were performed in the field with the salt solution resulting from the treatment by electrodialysis and subsequent ozonation. The results show that the plant height is comparable to synthetic fertilisers, but the crop yield is slightly lower. The latter is probably caused by volatilisation losses during field application, which can be prevented by improved application technologies

Methods to split cognitive task data for estimating split-half reliability: A comprehensive review and systematic assessment

Estimating the reliability of cognitive task datasets is commonly done via split-half methods. We review four methods that differ in how the trials are split into parts: a first-second half split, an odd-even trial split, a permutated split, and a Monte Carlo-based split. Additionally, each splitting method could be combined with stratification by task design. These methods are reviewed in terms of the degree to which they are confounded with four effects that may occur in cognitive tasks: effects of time, task design, trial sampling, and non-linear scoring. Based on the theoretical review, we recommend Monte Carlo splitting (possibly in combination with stratification by task design) as being the most robust method with respect to the four confounds considered. Next, we estimated the reliabilities of the main outcome variables from four cognitive task datasets, each (typically) scored with a different non-linear algorithm, by systematically applying each splitting method. Differences between methods were interpreted in terms of confounding effects inflating or attenuating reliability estimates. For three task datasets, our findings were consistent with our model of confounding effects. Evidence for confounding effects was strong for time and task design and weak for non-linear scoring. When confounding effects occurred, they attenuated reliability estimates. For one task dataset, findings were inconsistent with our model but they may offer indicators for assessing whether a split-half reliability estimate is appropriate. Additionally, we make suggestions on further research of reliability estimation, supported by a compendium R package that implements each of the splitting methods reviewed here

Characteristics of Adults Who Use Prayer as an Alternative Therapy

Purpose: To describe the demographics, health-related and preventive-health behaviors, health status, and health care charges of adults who do and do not pray for health. Design: Cross-sectional survey with 1-year follow-up. Setting: A Minnesota health plan. Subjects: A stratified random sample of 5107 members age 40 and over with analysis based on 4404 survey respondents (86%). Measures: Survey data included health risks, health practices, use of preventive health services, satisfaction with care, and use of alternative therapies. Health care charges were obtained from administrative data. Results: Overall, 47.2% of study subjects reported that they pray for health, and 90.3% of these believed prayer improved their health. After adjustment for demographics, those who pray had significantly less smoking and alcohol use and more preventive care visits, influenza immunizations, vegetable intake, satisfaction with care, and social support and were more likely to have a regular primary care provider. Rates of functional impairment, depressive symptoms, chronic diseases, and total health care charges were not related to prayer. Conclusions: Those who pray had more favorable health-related behaviors, preventive service use, and satisfaction with care. Discussion of prayer could help guide customization of clinical care. Research that examines the effect of prayer on health status should adjust for variables related both to use of prayer and to health status

It’s “mean,” but what does it mean to adolescents? Relational aggression described by victims, aggressors, and their peers

Abstract Early adolescent girls and boys (N = 33) with known histories of relational aggression and/or victimization gave detailed accounts of the nature, frequency, intensity, course, and impact of relational aggression among their peers. They also described reasons for, and forms of, aggression after being prompted by a series of hypothetical vignettes. Despite identifying many forms of aggression that were similar for girls and boys, some sex differences were found; girls were described as experiencing more victimization within close friendships than boys, with a focus on maintaining exclusivity. Boys described exclusion from larger groups with themes of masculinity, athletic skill, and/or perceived sexual identity. Girls' and boys' perceptions about the motivations for these different forms of relational aggression were quite similar. These included power, popularity, and wanting to fit in as well as the aggressors' emotional states and the victims' characteristics

Predictors of entering a hearing aid evaluation period: a prospective study in older hearing-help seekers

This study aimed to determine the predictors of entering a hearing aid evaluation period (HAEP) using a prospective design drawing on the health belief model and the transtheoretical model. In total, 377 older persons who presented with hearing problems to an ENT-specialist (n = 110) or a hearing aid dispenser (n = 267) filled in a baseline questionnaire. After four months, it was determined via a telephone interview whether or not participants had decided to enter a HAEP. Multivariable logistic regression analyses were applied to determine which baseline variables predicted HAEP status. A priori, candidate predictors were divided into ‘likely’ and ‘novel’ predictors based on the literature. The following variables turned out to be significant predictors: more expected hearing aid benefits, greater social pressure, and greater self-reported hearing disability. In addition, greater hearing loss severity and stigma were predictors in women but not in men. Of note, the predictive effect of self-reported hearing disability was modified by readiness such that with higher readiness, the positive predictive effect became stronger. None of the ‘novel’ predictors added significant predictive value. The results support the notion that predictors of hearing aid uptake are also predictive of entering a HAEP. This study shows that some of these predictors appear to be gender-specific or are dependent on a person’s readiness for change. After assuring the external validity of the predictors, an important next step would be to develop prediction rules for use in clinical practice, so that older persons’ hearing help seeking journey can be facilitated

The relationship between prevalence and duration of weight loss strategies and weight loss among overweight managed care organization members enrolled in a weight loss trial

BACKGROUND: Many adults in the United States report engaging in weight loss behaviors. The current study examined weight loss strategies among managed care organization members, to determine the prevalence and impact of weight loss behaviors in this population. We hypothesized that greater engagement in weight loss strategies would be associated with greater weight loss success. METHODS: Data were taken from Weigh-to-Be (WTB), a two-year weight loss trial (N = 1801, 72% female, mean age = 50.7 years, mean weight = 95.9 kg, mean BMI = 34.2 kg/m(2)). Every six months, participants completed a questionnaire assessing frequency and duration of weight loss strategies (calorie reduction, fat reduction, increased fruit/vegetable intake, increased exercise, elimination of sweets, consumption of less food). General linear models and structural equation methods were used to examine associations between weight loss strategy use and weight change over time. RESULTS: Weight loss strategy prevalence rates ranged from 68% to 76% over two years. For all dietary strategies, any use of the strategy between baseline and 24 months was associated with weight loss at 24 months; those who did not engage in the strategy showed weight gains during that period. Results of general linear models and structural equation models indicated that increased use of weight loss strategies was significantly associated with greater 24-month weight loss. CONCLUSION: The prevalence of weight loss strategies in this obese adult managed care population was quite high, and use of these strategies was associated in dose-response fashion with better weight loss. Future interventions may benefit from emphasis on persistence of similar strategies to achieve more successful outcomes