Modeling highway runoff pollutant levels using a data driven model.

Pollutants accumulated on road pavement during dry periods are washed off the surface with runoff water during rainfall events, presenting a potentially hazardous non-point source of pollution. Estimation of pollutant loads in these runoff waters is required for developing mitigation and management strategies, yet the numerous factors involved and their complex interconnected influences make straightforward assessment almost impossible. Data driven models (DDMs) have lately been used in water and environmental research and have shown very good prediction ability. The proposed methodology of a coupled MT-GA model provides an effective, accurate and easily calibrated predictive model for EMC of highway runoff pollutants. The models were trained and verified using a comprehensive data set of runoff events monitored in various highways in California, USA. EMCs of Cr, Pb, Zn, TOC and TSS were modeled, using different combinations of explanatory variables. The models' prediction ability in terms of correlation between predicted and actual values of both training and verification data was mostly higher than previously reported values. Pb(Total) was modeled with an outcome of R2 of 0.95 on training data and 0.43 on verification data. The developed model for TOC achieved R2 values of 0.91 and 0.49 on training and verification data respectively.

Assessment of the reliability of an on-site MBR system for greywater treatment and the associated aesthetic and health risks.

This study analyses the reliability of an on-site MBR system for greywater treatment and reuse. To achieve this goal simulation was performed based on the IWA ASM1 model which was adapted to describe biological and physical mechanisms for MBR greywater treatment based systems. Model results were found to agree well with experimental data from an on site pilot greywater treatment plant, after which the calibrated model was used in a Monte Carlo mode for generating statistical data on the MBR system performance under different scenarios of failures and inflow loads variations. Effluents quality and their associated risks were successfully estimated.

Kinneret watershed analysis tool: a cell-based decision tree model for watershed flow and pollutants predictions.

This paper presents the methodology and application underlying the Kinneret Watershed Analysis Tool (KWAT), developed for flow and contaminant predictions for Lake Kinneret (the Sea of Galilee) watershed located in northern Israel. Lake Kinneret watershed is about 2730 km2 (2,070 in Israel, the rest in Lebanon), inhabited by about 200,000 people organized in 25 municipalities, and three cities (the Israeli part). The model aims to predict flow and contaminant transports within the watershed, down to its outlet-Lake Kinneret, the most important surface water resource in Israel. The model is comprised of two sections: quantity and quality. The objective of the quantity section is to tune the values of a vector of coefficients alpha that multiply the average rainfall time series intensity I(t) (the input) imposed on given sub-sets (i.e., cells) of the basin so as to calibrate their outlet flows Q(t); the quality section then uses these optimal flows Q(t) and the effective optimal rainfall intensities to adjust the values of a vector of coefficients beta so as to calibrate the sub-watersheds outlet concentrations C(t). The model uses decision trees coupled with a genetic algorithm for optimally tuning the KWAT coefficients for each of the watershed cells, which taken together comprise the flow and contamination amounts measured at the watershed outlet.

Use of antihypertensive drugs and trends in blood pressure in the elderly.

BACKGROUND: During the 1980s data became available from randomized trials concerning the clear benefits of treating hypertension in the elderly. In three large communities, we examined the impact of these findings on rates of treatment, use of specific antihypertensive drugs, and rates of elevated blood pressure as well as distributions of levels. METHODS: In 1981 the National Institute on Aging initiated population-based cohort studies in the residents of three communities who were 65 years and older. East Boston, Mass; Washington and Iowa counties, Iowa; and New Haven, Conn. Participation rates ranged from 80% to 85% across sites with 10,294 community-dwelling participants in the combined cohorts. Baseline evaluation included inhome blood pressure assessment and medication inventory. Repeated in-home evaluations occurred 3 and 6 years after baseline and follow-up rates ranged from 71% to 88%. RESULTS: Use of antihypertensive drugs increased over time in all three communities: the age- and sex-adjusted rates of use were between 14% and 32% higher in 1988 and 1989 relative to 1982 and 1983. Parallel declines in the use of thiazide diuretics occurred in all three populations along with large increases in the use of angiotensin-converting enzyme inhibitors and calcium channel blockers. In East Boston and New Haven mean systolic blood pressure decreased substantially over time and the prevalence of elevated systolic pressure (> or = 160 mmHg) decreased overall as well as by age and sex. In Iowa the mean levels of systolic blood pressure were lowest at baseline and increased slightly. CONCLUSIONS: The reported evidence about the benefits of treatment for hypertension in the elderly was followed by substantial increases in treatment rates. The use of drugs with proven efficacy declined while the use of newer agents with theoretical advantages, not yet tested in clinical trials of mortality, increased. In the United States, the ongoing therapeutic efforts to lower elevated blood pressure in elderly populations may be contributing to the continuing decline in cardiovascular and stroke mortality.

Urinary free cortisol and separation anxiety early in the course of bereavement and threatened loss.

Among 56 persons who were acutely bereaved or threatened with a loss, a group with worsening separation anxiety over a period of a month early after the event had higher urinary free cortisol output than a group experiencing improvement in grief. Although not tested in this study, both these psychological and physiological measures may have potential for serving as early predictors of poor outcome in bereavement for the 15%-20% of exposed persons who are at risk for unresolved grief or persistent depressive syndromes.

Correlates of headache in a population-based cohort of elderly.

Data from a community-based study of 3811 persons aged 65 years and older were used to describe the characteristics of headache in the elderly. Subjects were asked whether they experienced headache in the past year, the frequency and severity of their headaches, and whether they experienced three symptoms of migraine: unilaterality, nausea or vomiting, an aura preceding the headache. Prevalence of headache in those aged more than 65 years declined with age in both men and women; women had a higher prevalence in each age group. The same was true for frequent, severe, and migrainous headache. We examined age- and sex-adjusted correlations of headache with several medical and social factors. Prevalence of any headache was strongly associated with joint pain, depression, bereavement, waking during the night, use of eyeglasses, symptoms of temporomandibular joint dysfunction, and self-assessment of health. Similar variables were associated with frequency, severity, and migrainous symptoms, and thus could not be distinguished among these various types.

Incidence of hospitalization for digitalis toxicity among elderly Americans.

OBJECTIVE: To document the prevalence of digitalis use and the incidence of hospitalization caused by digitalis toxicity. DESIGN: Observational cohort followed for 6 years. SETTING: Urban community. PARTICIPANTS: Persons were eligible if they were (1) enrolled in the Yale Health and Aging Project and (2) using digitalis when interviewed in 1982 or 1985. The Project comprises a sample of noninstitutionalized persons aged 65 years and over living in New Haven, Connecticut. METHODS: Between 1982 and 1988 when a Project participant was hospitalized in New Haven, a researcher reviewed the medical record and coded up to 16 International Classification of Diseases-Class 9 (ICD-9) diagnoses. To identify hospitalizations caused by digitalis, we reexamined records with ICD-9 codes suggesting toxicity. We confirmed the admission illness was an adverse drug reaction with a decision algorithm. RESULTS: The prevalence of digitalis use was 13% in 1982 and 12% in 1985. The incidence of hospitalization caused by definite or probable toxicity was 4.2% (95% confidence interval = 0.3% to 8.1%) over 6 years. Manifestations of toxicity were malaise or gastrointestinal symptoms (two patients) and heart block plus malaise or gastrointestinal symptoms (six patients). Use of quinidine was associated (P < .05) with toxicity. CONCLUSION: Knowledge about the incidence of severe, morbid toxicity may help clinicians estimate and compare the risks and benefits of digitalis and alternate therapies.

Frequency of long-term lower limb ischemia associated with intraaortic balloon pump use.

Lower limb ischemia is a frequent complication of intraaortic balloon pump (IABP) use. The incidence and risk factors for acute ischemia have been well-defined, but little is known about long-term ischemic complications. This prospective study evaluated the incidence, nature, progression and predisposing factors for long-term lower limb ischemia in 151 patients who were previously treated with the IABP. These persons were interviewed and their lower extremities examined 12 to 20 months after undergoing IABP counterpulsation. Limb ischemia, characterized primarily by ipsilateral discomfort and diminished pulses, occurred in 18% of those evaluated. Evidence of ischemia worsened over time in 14%. Logistic regression analysis, which was based on variables found to be significant in bivariate analysis, revealed that the occurrence of limb ischemia acutely, cardiogenic shock as an indication for IABP insertion, and smoking (at the time of hospitalization or having quit < 10 years previously) were risk factors for long-term lower limb ischemia. The adjusted odds ratio for acute limb ischemia was 8.89 (95% confidence interval 2.80 to 28.21), for cardiogenic shock 3.59 (95% confidence interval 1.01 to 12.75), and for smoking 2.87 (95% confidence interval 1.10 to 7.46). Increasing numbers of patients are undergoing IABP counterpulsation and a greater proportion of these are surviving their acute event and resuming active lives. It is essential to recognize that detrimental consequences of this device can persist long after hospitalization.

Anxiety disorders during acute bereavement: risk and risk factors.

Forty-four percent of bereaved spouses reported at least one type of anxiety disorder during the first year of bereavement in a survey of a representative sample composed of a subgroup (N = 48) assessed 6 months after bereavement and another subgroup (N = 54) assessed 12 months after bereavement. The bereaved spouses experienced 6-month prevalence rates for panic disorder and generalized anxiety disorders that were higher than community prevalence rates for the same metropolitan area (p less than .01). Past personal history of anxiety disorder was an independent risk factor (p less than .05), and anxiety disorders were associated with severe grief (p less than .01) and depression (p less than .05). The large overlap of anxiety disorders with major depression observed in this study indicates that the estimated rates of anxiety disorder are not independent of major depression in most cases and raises questions about whether the anxiety disorders of bereavement are prodromal, concomitant, or residual with respect to major depression.

Malnutrition and subsequent ischemic heart disease in former prisoners of war of World War II and the Korean conflict.

The harsh treatment of former prisoners of war (POWs) of World War II and the Korean conflict resulted in severe malnutrition. Although rarely linked to specific long-term medical problems, a specific marker of malnutrition, self-reported lower limb edema (presumably due to a vitamin B deficiency) was associated with a three-fold increase in subsequent death attributed to ischemic heart disease (IHD) during the follow-up period from 1967 through 1975. Although there is at present no medical basis for linking edema, which is perhaps a marker for some unmeasured risk factor, to subsequent IHD, this finding may nonetheless have medical implications for the group of former POWs and other populations with severe dietary deficiency. It also suggests there may be a need to reexamine currently held theories on malnutrition and subsequent chronic disease.

Serum albumin in older persons: relationship with age and health status.

We analyzed data from 4115 persons aged 71 years and older who had blood drawn at a home visit in three communities to examine the cross-sectional distribution of serum albumin and correlates of hypoalbuminemia. Mean albumin was lower among older persons, from 41.6 g/l in men aged 71-74 years to 38.5 g/l in men 90 years or older, and from 41.1 g/l to 38.9 g/l in women of the same ages, respectively. Hypoalbuminemia (albumin less than 35 g/l) was observed in 3.1% of subjects. Hypoalbuminemia and lower serum albumin were independently associated with anemia, recent diagnosis of cancer, two or more limitations in activities of daily living, residence in a nursing home, heavy cigarette smoking (greater than 1 pack/day), and older age. A 10-year age increment was associated with 0.8 g/l lower serum albumin and odds ratio of 1.56 (95% CI 1.14, 2.13) for hypoalbuminemia after adjusting for demographic factors and health status. Characteristics associated with serum albumin may confound the reported relationship between serum albumin and mortality.

Analysis of data from successive complex sample surveys, with an example of hypertension prevalence from the United States Health Examination Survey.

There are a number of ongoing large complex sample surveys focused on health data being undertaken at present. Because of time and cost constraints, these surveys are usually highly stratified multistage cluster samples. The complexity of this design has made the usual simple random sampling assumptions untenable and therefore analyses are rarely more than descriptive in nature with some pairwise comparison using t-tests. Generalized regression procedures using weighted least squares are now available for solving this difficulty by incorporating the sample design into the data analysis through the variances and covariances of the sample estimates. These procedures are extended to the analysis of data from complex surveys conducted at two or more different points in time (successive surveys). The method is illustrated with an example taken from published data of hypertension prevalence estimates from the Health Examination Survey-Cycle I (1960-1962) and the Health and Nutrition Examination Survey (1971-1975).

The clinical management of grief.

The clinical management of grief involves issues that demonstrate the integration of psychosocial risk factors into clinical practice. Recommendations for the clinical management of grief are based on a review of the pattern of morbidity and mortality of bereavement, of the emotional response to conjugal loss, and of several postulated pathogenetic mechanisms.

The systemic use of procaine in the treatment of the elderly: a review.

This article is a review and evaluation of the world literature on the systemic use of procaine in the treatment of the aging process and the common chronic diseases of later life. Included are data from 285 articles and books, describing treatment in more than 100,000 patients in the past 25 years. Except for a possible antidepressant effect, there is no convincing evidence that procaine (or Gerovital, of which procaine is the major component) has any value in the treatment of disease in older patients. If procaine has an antidepressant effect, there is some likelihood that this accounts for the reports of decreased complaints referable to the musculoskeletal, cardiovascular, endocrine sexual, gastrointestinal and respiratory systems.

Association of visual impairment with mobility and physical function.

OBJECTIVE: To examine the association of distant vision and physical function in the population of older adults. DESIGN: Cross-sectional and cohort study. PARTICIPANTS: 5143 older residents of three communities (Established Populations for the Epidemiologic Studies of the Elderly) who were interviewed in 1988-89, including residents of two communities who were re-interviewed 15 months later (n = 3133, 97% of those eligible). MEASURES: Visual acuity screening, self-reported activities of daily living and mobility, and objective physical performance measures of balance, walking, and rising from a chair. RESULTS: Limitations in mobility, activities of daily living, and physical performance were associated with worse visual function. In prospective analyses controlling for potential confounders, participants with severe visual impairment had 3-fold higher odds of incident mobility and activity of daily living limitations than those with acuity of 20/40 or better (P < 0.001). In prospective analyses investigating the relationship of vision with improvement in function, those with poor vision were about half as likely to improve as those with better acuity, but this relationship was only statistically significant for improvement in mobility limitations. CONCLUSIONS: Distant visual function appears to play an important role in physical function, particularly for mobility. An intervention to improve vision in at-risk elders might preserve function and prevent disability; this warrants further investigation.

Anemia and hemoglobin levels in older persons: relationship with age, gender, and health status.

OBJECTIVE: To determine the relationship of hemoglobin levels and anemia with age and health status in older adults. DESIGN: Survey. SETTING: Community. PARTICIPANTS AND METHODS: Hematologic tests were obtained from 3,946 adults aged greater than or equal to 71 years in three communities (East Boston, MA; Iowa and Washington counties, IA; and New Haven, CT). RESULTS: Hemoglobin level was inversely associated with age, although this was more pronounced in men than in women. The proportion anemic was equal for men and women aged 71-74 years (8.6%) and increased differentially with age, reaching 41% and 21% for men and women aged greater than or equal to 90 years, respectively. Hemoglobin and anemia were independently associated with age, race, body-mass index, smoking, cancer, hospitalization, renal insufficiency, and hypoalbuminemia. The adjusted relative odds of anemia for a 5-year increase in age was 1.5 (95% confidence interval [CI] 1.3-1.8) for men and 1.2 (95% CI 1.1-1.4) for women. CONCLUSIONS: Age is significantly associated with both hemoglobin levels and anemia, with a stronger effect in men compared with women, even after simultaneously adjusting for demographic characteristics and health status. The decline of hemoglobin and concomitant increased anemia with age is not necessarily a result of "normal aging" so the detection of anemia in an older person should prompt appropriate clinical attention.

Intermittent claudication and subsequent cardiovascular disease in the elderly.

BACKGROUND: This study reports the prevalence of intermittent claudication (IC) in ambulatory community-resident adults age 65 years or older, compares cardiovascular risk factors and comorbidity of persons with and without IC, and examines the independent association of IC in predicting all cause and cardiovascular mortality, myocardial infarction, stroke, and disability. METHODS: Data are from a pooled sample of 8996 older adults from the East Boston, New Haven, and Iowa sites of the Established Populations for Epidemiologic Studies of the Elderly, conducted between 1982 and 1988. RESULTS: 2.4% and 1.5% of men and women, respectively, reported IC. Persons with IC had significantly higher rates of diabetes and cardiovascular comorbidity than persons without IC, and they were more likely to smoke. Claudication predicted higher rates of mortality, myocardial infarction, stroke, and disability independent of associated cardiovascular conditions and risk factors. Among persons with a history of angina, myocardial infarction, and/or stroke, those who reported IC had a twofold greater risk of cardiovascular mortality. CONCLUSION: The study demonstrated that IC is an important predictor of mortality and cardiovascular morbidity in ambulatory older adults independent of associated coronary ischemia and cardiovascular disease risk factors. Results suggest that inclusion of a measure of IC improves the prediction of cardiovascular morbidity and mortality in older adults.

Effects of sex on differences in awareness, treatment, and control of high blood pressure.

Our purpose was to explain the reasons for sex differentials in the awareness, treatment, and control of hypertension by identifying major social and behavioral predictors of these three sequential stages of high blood pressure control. We analyzed data on all 1,433 hypertensive subjects from the First Connecticut Blood Pressure Survey. Hypertensive women were more likely than hypertensive men to be aware of their high blood pressure (odds ratio = 1.40; confidence interval = 1.10-1.79) and to have controlled levels of blood pressure (odds ratio = 1.62; confidence interval = 1.08-2.44). Men and women who were aware of their hypertension were equally likely to be treated. Sex still explained differences in awareness and control of hypertension after adjusting for other significant variables. We conclude that sex is an important predictive covariate for adjustment in explaining differences in awareness and control of high blood pressure. Health care professionals should be aware of the differential role of sex when informing and treating hypertensive patients.

Spouse similarities in high blood pressure knowledge: implications for control of high blood pressure.

This study describes the general knowledge about high blood pressure of husbands and wives using data from all 1,260 white spouse pairs from the 1982 Connecticut Blood Pressure Survey and examines the relationship between high blood pressure knowledge and control of hypertension. We found the average level of knowledge to be high; about 70% of the items were answered correctly. The correlation between spouses' knowledge about high blood pressure was significantly high (r = .41). Multiple regression analysis was used to control for other variables that might influence the spousal correlation in knowledge. When controlling for education, age, socioeconomic status, and hypertension status of both spouses, the correlation between spouses' knowledge remained significant (r = .24). Respondents' knowledge and spouses' knowledge about high blood pressure were significantly related to high blood pressure control among hypertensive persons, particularly to being aware of hypertension and being in current treatment.

Depressive symptoms in the elderly: association with total white blood cell count.

1. The white blood cell (WBC) count in those with high depressive symptoms and non-depressed participants in the Established Populations for Epidemiologic Studies of the Elderly (EPESE) were compared. 2. Of 3769 participants 10.8% had high depressive symptoms as assessed by the Centers for Epidemiologic Studies Depression (CES-D) Scale. The mean white blood cell count was higher in the high depressive symptoms group compared to the non-depressed group (6.8 +/- 0.12 x 10(9) WBC/1 and 6.5 +/- 0.03 x 10(9) WBC/1, respectively, p < 0.01). 3. Because older adults frequently have disabling chronic conditions which could both influence their leukocyte count and cause depressive symptoms, models were developed which controlled for the potential confounding. Even after adjusting for potential confounders, high depressive symptoms were still associated with higher white blood cell counts.