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Stream temperature (Ts) is a key water quality parameter that controls several biological, ecological, and chemical processes in aquatic systems. In forested headwaters, exchanges of energy across air‐water‐streambed interfaces may influence Ts regimes, especially during storm events as the sources of runoff change over space and time. Analysis of the hysteretic behaviour of Ts during storm events may provide insights into rainfall‐runoff responses, but such relationships have not been thoroughly investigated. As such, our objectives were to (a) quantify the variability of stream temperature hysteresis across seasons in different sub‐regions and (b) investigate the relationship between the hysteretic response and catchment characteristics. Ts hysteresis during storm events was assessed based on the hysteresis index (HI), which describes the directionality of hysteresis loops, and the temperature response index (TRI), which indicates whether Ts increased or decreased during a storm event. We analysed Ts data from 10 forested headwater reaches in two sub‐regions (McGarvey and West Fork Tectah) in Northern California. We also performed a clustering analysis to examine the relationship amongst HI, TRI, topographic metrics, and meteorological characteristics of the study areas. Overall, the hysteretic behaviour of Ts varied across seasons—the greatest HI occurred during spring and summer. Interestingly, in the McGarvey streams the variability in Ts hysteresis co‐varied strongly with topographic metrics (i.e., upslope accumulative area, average channel slope, topographic wetness index). Comparatively, in West Fork Tectah the variability of Ts hysteresis co‐varied most strongly with meteorological metrics (i.e., antecedent rainfall events, solar radiation, and air temperature). Variables such as the gradient between stream and air temperatures, slope, and wetted width were significant for both sub‐regional hysteretic patterns. We posit that the drivers of Ts response during storms are likely dependent on catchment physiographic characteristics. Our study also illustrated the potential utility of stream temperature as a tracer for improving the understanding of hydrologic connectivity and shifts in the dominant runoff contributions to streamflow during storm events. [ABSTRACT FROM AUTHOR]

Purpose: Anti-tumor necrosis factor-alpha (anti-TNF) therapies are associated with severe mycobacterial infections in rheumatoid arthritis patients. We developed and validated electronic record search algorithms for these serious infections., Methods: The study used electronic clinical, microbiologic, and pharmacy records from Kaiser Permanente Northern California (KPNC) and the Portland Veterans Affairs Medical Center (PVAMC). We identified suspect tuberculosis and nontuberculous mycobacteria (NTM) cases using inpatient and outpatient diagnostic codes, culture results, and anti-tuberculous medication dispensing. We manually reviewed records to validate our case-finding algorithms., Results: We identified 64 tuberculosis and 367 NTM potential cases, respectively. For tuberculosis, diagnostic code positive predictive value (PPV) was 54% at KPNC and 9% at PVAMC. Adding medication dispensings improved these to 87% and 46%, respectively. Positive tuberculosis cultures had a PPV of 100% with sensitivities of 79% (KPNC) and 55% (PVAMC). For NTM, the PPV of diagnostic codes was 91% (KPNC) and 76% (PVAMC). At KPNC, ≥ 1 positive NTM culture was sensitive (100%) and specific (PPV, 74%) if non-pathogenic species were excluded; at PVAMC, ≥1 positive NTM culture identified 76% of cases with PPV of 41%. Application of the American Thoracic Society NTM microbiology criteria yielded the highest PPV (100% KPNC, 78% PVAMC)., Conclusions: The sensitivity and predictive value of electronic microbiologic data for tuberculosis and NTM infections is generally high, but varies with different facilities or models of care. Unlike NTM, tuberculosis diagnostic codes have poor PPV, and in the absence of laboratory data, should be combined with anti-tuberculous therapy dispensings for pharmacoepidemiologic research., (Copyright © 2010 John Wiley & Sons, Ltd.)

Objective: Describe gender differences in hospitalizations for IDDM to investigate the need for gender-specific interventions to reduce diabetes-related morbidity., Research Design and Methods: Analyses were based on hospital discharges with any mention of IDDM (n = 2,889) and the subset of these for IDDM as a principal diagnosis (n = 2,270) in California children, ages 0-18 years during 1991. Pregnancy-related hospitalizations were excluded., Results: Females had more diabetes hospitalizations among discharges with any mention of diabetes, among discharges with diabetes as a principal diagnosis, and among discharges with diabetic ketoacidosis as a principal diagnosis. For diabetes as a principal diagnosis, females had 40% more hospitalizations, 44% more repeated hospitalizations, 23% more individuals hospitalized, and significantly higher rates of hospitalizations for ages 10-14 years (50 vs. 38 per 100,000) and for ages 15-18 years (68 vs. 29 per 100,000). Gender differences occurred primarily in adolescents, were independent of complicating conditions at the time of hospitalization, and were observed for diabetic ketoacidosis alone., Conclusions: Adolescent females had more diabetes hospitalizations than did males. The underlying cause may be biological or behavioral. Management protocols tailored for young women may be required to reduce hospitalizations for IDDM among females.

As a follow-up to an observed fourfold excess of malignant melanoma among workers at Lawrence Livermore National Laboratory, Alameda County, California, the authors conducted a case-control interview study of 31 cases diagnosed during the period 1969-1980 and 110 individually matched controls. Respondents were queried regarding familial cancer history, health history, general health behaviors, socioeconomic status, sun-exposure history, skin sensitivity to sunlight, and detailed occupational and occupational exposure history. Measurements were taken of constitutional risk factors such as eye color and skin reflectance. The associations between nonoccupational risk factors and case status were consistent with those reported from population-based studies of malignant melanoma. Several occupational indicators of risk were strongly associated with case status. These included chemist duties (odds ratio (OR) = 8.0), as well as work around high explosives (OR = 3.0), volatile photographic chemicals (OR = 3.0), and sources of ionizing radiation (OR = 3.7). Multivariate analyses of these risk associations suggested each to have a reasonably independent relation to case status. After adjustment for constitutional and occupational risk factors of interest, the odds ratio associated with reported work around sources of ionizing radiation remained elevated (OR = 2.3, 95% confidence interval 1.0-7.6). The authors believe these results to be sufficiently suggestive to warrant additional studies of occupational factors and risk for malignant melanoma of the skin.

A focus-group study gathered qualitative information from Hispanic males in California regarding ethnic factors that might enhance or interfere with AIDS prevention efforts. A predominantly working-class convenience sample of 75 men aged 18-40 participated in seven groups of 10-12 participants each. Three groups were composed of single men, three of married men and one was composed of homosexual and bisexual men. Four groups included only participants born outside the United States; and Spanish was the preferred language in five of the groups. Evaluation of the discussions indicates that while AIDS awareness is high among this population, condom use is sporadic. Few participants knew that someone infected with the human immunodeficiency virus could appear healthy; most believed they could easily determine if a woman is risky by her appearance or social standing. Although many participants thought HIV could be transmitted through casual contact, the homosexual and bisexual men were more likely to acknowledge that they were at some risk of infection; most of the heterosexual men did not perceive themselves as being at risk, even those who engaged in sex with prostitutes or women they met at bars. The participants had ambivalent attitudes toward women who suggested condom use and were often reluctant to initiate condom use themselves. Religion did not seem to play a major role in the men's attitudes about AIDS, sexuality and condom use.

We studied the relation between occupation and oral and pharyngeal cancer with a population-based case-control study conducted in four areas of the United States. The study group included 1,114 incident male and female cases and 1,268 frequency-matched controls. After adjustment for age, race, smoking, alcohol, and study location, an analysis of lifetime occupational histories revealed a small number of noteworthy associations. Risk was increased among male carpet installers (23 cases, 4 controls), with an adjusted odds ratio of 7.7 [95% confidence interval (CI) = 2.4-24.9], and tended to rise with longer duration of employment. A decreased risk was found among male and female textile mill workers (odds ratio 0.48, 95% CI = 0.27-0.88). Previously reported increases in oral cancer risks among printing workers, electrical and electronics workers, and workers other than carpet installers who were possibly exposed to formaldehyde were not found in this study. For several employment groups, including male machinists, primary metal industry workers, petroleum industry workers, painters, furniture and fixture industry workers, woodworking machine operators, and workers with inferred exposure to fossil fuel combustion, odds ratios were approximately 2.0 for cancers of pharyngeal sites.

The primary objective of this study was to assess the feasibility of using a population-based tumor registry to identify occupational groups at high risk of developing cancer. The study group comprised 6,424 union members residing in the San Francisco/Oakland Standard Metropolitan Statistical Area (SMSA) who represent six occupations: asbestos workers, bakers, painters, plasterers, plumbers and roofers. Computer linkage of union rosters to the California Tumor Registry (CTR) file identified incident cases of cancer. The CTR's age-sex-year-specific incidence rates were used to calculate the expected number of cancer cases, and estimated standardized incidence ratios (SIRs). The results demonstrate, as expected, increased cancer incidence (SIR = 498) for trachea, bronchus, lung and pleura among asbestos workers, a group widely recognized as having high risk for respiratory cancers, and among painters (SIR = 199). Strengths and weaknesses of such an approach are discussed.

The cancer incidence from 1969 through 1980 among active members of an occupational cohort (the Lawrence Livermore National Laboratory [LLNL] was compared with that of the same-age sector of the total population of the San Francisco-Oakland Standard Metropolitan Statistical Area. Excesses were found for malignant melanoma of the skin and salivary gland tumors and a deficit for lung cancer in men. No excesses were noted for radiosensitive tissue groups. The overall incidence of cancer among LLNL employees for this time period is approximately that for the general population.

The Third National Cancer Survey of 1969--71 included the five counties of the San Francisco--Oakland Standard Metropolitan Statistical Area. The complete cancer reporting for this area, begun by the Third National Cancer Survey, was continued by the California Tumor Registry as part of the San Francisco Bay Area Resource for Cancer Epidemiology. The population-based cancer-reporting system provided an excellent data base for epidemiologic studies, a number of which (planned or in progress) were described briefly. Those in progress include: cancer of the ovary, corpus uteri, and breast as related to child bearing, fertility, exogenous hormones, etc.; the relationship of diet to breast cancer occurrence among Japanese; diet and colorectal cancer among blacks; and the relationship of cervical cancer to cytology in Alameda County. Other study proposals are under consideration.

Using mortality and incidence data from Alameda County, California, this study attempted to determine whether the higher occurrence rate of prostatic cancer among black men as compared with whites in the United States might be explained by racial differences in factors associated with socioeconomic status. Each death or case of prostatic cancer was assigned to a social class based on census tract of residence, and rates by race and socioeconomic status were computed. Comparison of age-specific mortality and incidence rates by socioeconomic status reveals no gradient in either whites or blacks. The higher risk for blacks holds up at almost every age and socioeconomic level. However, the racial differences are less pronounced for incidence than for mortality. Racial differences in the occurrrence of deaths appearing in Part II of the death certificate are also examined.

Among the most striking epidemiologic characteristics of prostatic cancer in the United States is the sizeable excess in rates for the disease among blacks as compared with whites. This study attempted to determine whether the higher black rates might be explained by controlling for social class, using mortality data from Alameda County for the pericensal period 1968--1972 (n = 400), and the population-based series of cases for Alameda County included in the Third National Cancer Survey, 1969--1971 (n = 750). Reviewed first are previous studies addressed to the relationship of prostatic cancer and socioeconomic status (SES), most of which have been confined to whites. In the present study, each death or case was assigned to a socioeconomic class based on census tract of residence and rates by race and social class determined. Comparison of age-specific mortality and incidence rates by SES reveals no gradient for prostatic cancer in either whites or blacks.

The 10% increase in the incidence of all cancer observed in the total white population of the San Francisco Bay Area during 1970-75 is mostly due to the 19% increase in cancer among white females. The latter is largely a result of increased incidence of cancer of the corpus uteri, breast, and lung, and of malignant melanoma. Cancer of these four sites constitutes 85% of the increase in white women. The rise in uterine corpus cancer is limited to women over 50 years of age. An incidence peak in 1974 of breast cancer was followed by a substantial decrease in 1975. The 50% rise in female lung cancer is an extension of the increase that began in 1965. The almost 70% increase in melanoma among women since 1975 accompanies a comparable increase in melanoma among males after a decade of stable incidence rates.

A significant rise in the incidence of carcinoma of the corpus uteri in women of the San Francisco-Oakland standard metropolitan statistical area (SMSA) was reported by the Resource for Cancer Epidemiology. The incidence among white females increased by over 50% in the 6 years between 1969 and 1975. The increase was limited to the groups over 50 years old and to invasive cancers of the endometrial lining. The increase occurred in all five of the SMSA counties and, in white women in Aalmeda County, the average annual incidence for the 50- to 74-year age group tripled in 15 years. The rise was greatest in the areas of most affluence. Possible spurious causes of increase, such as changing diagnostic criteria, better case finding, or better reporting were examined and ruled out. The data suggested that the increase was due to the recent introduction of a potent endometrial carcinogen to the population group affected.

The incidence of endometrial cancer in the San Francisco area between 1969 and 1979 is compared to trends in estrogen sales and prescriptions. Both estrogen use and endometrial cancer incidence increased steadily until 1975 and then decreased significantly. The data support the previously documented association between endometrial cancer and estrogen use, but suggest that short-term usage may carry only slightly increased risk which can be eliminating entirely upon termination of therapy.

There have been many studies conducted of mortality in occupational cohorts, but few of cancer incidence. Two major facilities of the Western Division of Dow Chemical USA are located fortuitously within an area covered by the population-based California Tumor Registry, which allowed linkage of records to identify incident cancers among 1,403 male workers. Using adjusted county rates for comparison, 49 new cancers were observed in the cohort from 1969 through 1983, whereas 63.0 were expected (standardized incidence ratio = 78, 95% confidence limits = 53 to 103). Nonsignificant excesses were noted for several cancer groups among some categories of workers; however, there was no predominant tumor type within the groups. The successful completion of this collaborative project suggests that using population-based tumor registries for surveillance of occupational cohorts is feasible.

Previous investigations have drawn conflicting conclusions concerning the association between childhood leukemia and maternal age, birth order, socioeconomic status, and paternal occupation. In this study, 255 childhood leukemia cases diagnosed in California between 1975 and 1980 were individually matched with two living controls on the basis of sex, date of birth, and county of birth. Data were derived from subjects' birth certificates. Socioeconomic status and paternal benzene exposure were determined from the paternal occupation stated on the birth certificate. Hispanics and males were overrepresented in the case group. Cases were also less likely to be of birth order one. No difference was found between case and control groups for maternal age or paternal occupation. Analyses with stratification on age, sex, and leukemia cell type are reported.

19 cases of malignant melanoma (MM) were observed during 1972-77 among approximately 5100 employees of the Lawrence Livermore National Laboratory, where high energy physics research is conducted. This number was significantly higher (p less than 2 X 10(-6)) than that expected in a comparable age/race/sex/geographical segment of the population of the San Francisco Bay Area. The excess seemed to occur only among laboratory employees and not among the surrounding community, which suggests that an occupational factor is responsible. Preliminary case-comparison findings suggest that MM risk is not associated with length of employment at the laboratory nor with type of monitored radiation exposure. Although the data did not support an association between MM incidence and all scientific job classifications combined, an excess relative risk was observed among chemists. The reasons for the MM excess have not been identified.

In San Francisco, the crude incidence rate of squamous cell cancer of the rectum or anus in males averaged 11.3/million and 8.8/million in females in 1972-77. In the 4 other counties of the San Francisco-Oakland Standard Metropolitan Statistical Area, the rates were 3.8 in males and 7.3 in females. Fifty-five percent of the San Francisco male patients were single (i.e., never married) and, for the remaining counties, 18% were single. One-fifth to one-fourth of the adult population of San Francisco is believed to be homosexual. Thus a high rate of squamous cell carcinoma of the rectum or anus is associated with single males in a county widely noted for its homosexual community. This is consistent with a hypothesis that a venereally transmissable agent or its treatment is responsible for some portion of the incidence of that tumor.

Two series of data from the California State Department of Health and one from Children's Hospital of Los Angeles were analyzed to determine whether an association exists between influenza epidemics and incidence of leukemia in children born following such outbreaks. Of leukemic children born in areas for which information on past influenza activity was available, the population-based Alameda County Cancer Registry recorded 89 cases during 1960-1969, the California Tumor Registry recorded 653 cases during 1950-1970, and Children's Hospital recorded 575 cases during 1957-1972. Flu epidemics were identified and flu cohorts constructed such that leukemic children who could have been in utero during a flu epidemic constituted a flu cohort. Based on the total number of leukemia cases reported and the proportion of at-risk weeks contributed by the flu cohort, expected numbers of leukemia cases from the flu cohort were computed for each age. In each series, there was an excess of leukemia cases in the flu cohort, contributed primarily by the 0-4 age group. Trimester analysis indicated that the greatest excess occurred in children who were in the first trimester of gestation during a flu epidemic. Incidence data from the Cancer Incidence System of the San Francisco Bay Area Resource for Cancer Epidemiology and the Third National Cancer Survey show a relative risk of 3.4 for this group. Due to sources of misclassification in this study, such as analysis of flu cohorts rather than individuals whose mothers actually had influenza during pregnancy, the results tend to be diluted. If influenza is a causative factor, the actual increase in leukemia risk is likely to be much greater than this analysis indicates.

To gather data on which to base the design of an intervention program to decrease cancer mortality in the black population of California, physician members of the Golden State Medical Association were surveyed to determine their current practices relating to early cancer detection and cancer prevention. Respondents' estimates of the proportions of their patients in various categories indicated that at least 60% to 70% of their patients were potential subjects for intensive early cancer detection and cancer prevention efforts. Thirty-four percent of respondents reported that they were performing early cancer detection examinations on all their patients. On the average, respondents estimated that about 70% of their patients (more than 80% of patients of primary care physicians) were receiving either routine check-ups or specific early cancer detection examinations. Patient education about various aspects of cancer and cancer prevention emerged as the most readily attainable means to reduce cancer mortality in blacks. It was most frequently mentioned both as something that physicians could do to help achieve this goal and as an outside resource physicians would find useful in their practices. Its lack was cited as the greatest barrier to early cancer detection and cancer prevention in the black population.