bluuebunny/crossref_metadata_2025 huggingface dataset:
“I Gotta Push. Please Let Me Push!” Social Interactions During the Change from First to Second Stage Labor
Authors: Bergstrom Linda , Seidel John , Skillman‐Hull Leslie , Roberts Joyce
Published: August 2010

Background:

Forms of social interaction may occur among the participants in medicalized births, in which a woman in labor is experiencing strong involuntary urges to push but has not yet been found to have a completely dilated cervix. This article examines the social events and communications that occur at the change between first and second stages of labor.

Method:

Three cases are described from videotapes of women in the second stage of labor and their caregivers.

Results:

Several social and interactive features occurred, in which (1) the caregiver, usually a nurse, by invoking the “no pushing rule,” insisted that the woman suppress her involuntary urges to push; (2) both the caregiver and the parturient displayed an orientation toward the future and the eventual certification of full cervical dilation by a designated authority, usually a physician, regardless of the actual state of the woman's cervix or her involuntary urges to push; and (3) the certification process marked a ritual transition to “official” second stage labor, in which the woman's involuntary urges were considered appropriate and actively encouraged.

Conclusion:

A discrepancy between a laboring woman's sensations and caregivers' ideas about how labor should be conducted has implications for clinical care of women, wherein the goal should be to facilitate the woman's accomplishment rather than to direct the “delivery.” (BIRTH 24:3, September 1997)
Toward Lower Cesarean Birth Rates and Effective Care: Five Years' Outcomes of Joint Private Obstetric Practice
Authors: Schimmel Lynn M. , Schimmel Leon D. , DeJoseph Jeanne
Published: August 2010

Background

Many ways to improve perinatal outcomes, deliver cost‐effective care, and increase client and caregiver satisfaction have been suggested. This article adds to the body of such literature by describing a joint practice in California and reporting five years of its outcomes.

Method:

Frequency data were recorded prospectively for all pregnant women seen between January 1, 1991, and December 31, 1995. Overall statistics and variable‐specific frequencies were then analyzed for the 1303 consecutive singleton births that occurred during this period.

Results:

The primary cesarean birth rate for the sample was 6.5 percent, the total rate was 9.1 percent, and the rate for women having their first full‐term pregnancy was 11.3 percent. Of all women with a previous cesarean birth, 72.2 percent delivered vaginally. The success rate of attempted vaginal births after cesarean was 83.5 percent. Instrument deliveries were performed for 2.0 percent of births, and the frequency of third‐ or fourth‐degree lacerations was 3.0 percent of all vaginal births. Transfers to a tertiary neonatal intensive care unit were 1.3 percent, and the perinatal mortality rate was 5.4 per 1000 births (corrected for serious anomalies: 3/1000). The preterm birth rate (including maternal transfers) was 2.0 percent.

Conclusion:

An obstetric practice in a private community hospital setting that effectively used obstetricians, nurse‐midwives, and nurse practitioners reported low rates of cesarean birth, preterm birth, severe lacerations, instrument deliveries, and legal incidents, and excellent cost‐effective maternal and neonatal outcomes. (BIRTH 24:3, September 1997)
Maternal Health Care at a Japanese American Relocation Camp, 1942–1945: A Historical Study
Authors: McKay Susan
Published: August 2010

Background:

From late summer of 1942 until the fall of 1945, approximately 120,000 ethnic Japanese were confined behind barbed wire within 10 relocation camps in the United States. Although histories have been written about the relocation camps, little data are available about women's lives. This study explored women's lives and experiences with pregnancy, childbirth, and child care in a Japanese‐American relocation camp.

Methods:

Twenty women who were ages 18 to 31 years at the time of internment at Heart Mountain, Wyoming Japanese American Relocation Camp, and one caucasian nurse who worked in the obstetric unit of the camp's hospital were interviewed. Archival, demographic, and historical data, including some prenatal records, provided information about maternity and public health care for pregnant women and new mothers.

Results:

Obstetric hospital practices were typical of the 1940s in the United States. Community public health services for new mothers included formula kitchens and well‐baby clinics. Infant mortality statistics from 1942 to 1945 at Heart Mountain were comparatively better for the same time period than for the state of Wyoming or the United States. These outcomes may have reflected the camp's extensive social and family support, adequate housing and food, and universal access to maternity services.

Conclusions:

The Heart Mountain internment provides a story about how women's lives are impacted by war. Since World War II, civilians, especially women and children, have increasingly been targeted during wars with profound impact upon the health of mothers and babies. (BIRTH 24:3, September 1997)
Women's Evaluations of Induction of Labor Versus Expectant Management for Prelabor Rupture of the Membranes at Term
Authors: Hodnett Ellen D. , Hannah Mary E. , Weston Julie A. , Ohlsson Arne , Myhr Terri L. , Wang Elaine E.I. , Hewson Sheila A. , Willan Andrew R. , Farine Dan ,   for the TermPROM Study Group
Published: August 2010

Background:

Induction of labor has become common practice in many Western countries, but few studies have assessed women's views.

Methods:

A randomized, controlled trial was conducted at 72 hospitals in six countries. Five thousand forty‐one women meeting eligibility criteria, with no contraindications for induction of labor or expectant management, were randomly assigned to four groups: induction with intravenous oxytocin, induction with vaginal prostaglandin E2 gel, or expectant management followed by induction with either oxytocin or with prostaglandin E2 gel if complications developed. The three main outcome measures were evaluations of the treatment received, perceived control during childbirth, and evaluations of the experience of trial participation.

Results:

Questionnaires were completed by 81.9 percent of the sample. No significant differences occurred between the two induction groups. Compared with the expectant management groups, induced women were less likely to report there was nothing they liked about their treatment and less likely to report that the treatment caused additional worry. No between‐group differences occurred in experienced control during childbirth. Women in the induction groups were more likely to be willing to participate in the study again and to feel reassured.

Conclusions:

Women's preferences should be considered when making decisions about their method of management when membranes rupture before labor. Obtaining participants' views is both feasible and worthwhile when evaluating forms of medical care. (BIRTH 24:4, December 1997)
Unintended Childbearing, Maternal Beliefs, and Delay of Prenatal Care
Authors: Mayer Jeffrey P.
Published: August 2010

Background:

Delay of prenatal care is an important risk for poor birth outcome, yet its association with maternal knowledge and beliefs remains insufficiently studied. This research examined the relationship of unintended childbearing and beliefs about the importance of prenatal care with initiation after the first trimester, adjusting for key sociodemographic determinants.

Methods:

One hundred fifty‐four Texas hospitals accounting for 80 percent of state births were asked to collect surveys from all women delivering infants during a one‐week interval in 1986. Seventy‐four percent of hospitals and 70 percent of women participated (n= 2032). No differences occurred between the sample and the population on rates of delayed care and low birthweight or maternal demographics.

Results:

Since delayed prenatal care is more frequent among low‐income women, analyses were limited to those below the 200 percent poverty level. After adjustment for maternal age, marital status, education, parity, race, and health insurance status employing logistic regression, unintended births were 1.6 times more likely to involve delayed care. Mothers who believed prenatal care was unimportant were 2.1 times more likely to delay care. These coefficients exceeded or about equaled those for the covariates.

Conclusions:

Preconception education about the value of prenatal care and family planning programs to prevent unintended pregnancies should be conducted together with efforts to overcome financial and structural barriers if progress toward national prenatal care objectives is to be achieved. (BIRTH 24:4, December 1997)
Cesarean Birth Trends in Chile, 1986 to 1994
Authors:   Licenciada en Sociología, F. Murray Susan , Pradenas Fanny Serani
Published: August 2010

Background:

Despite indications of high cesarean section rates in various parts of Latin America, relatively few comprehensive studies of national birth intervention trends have been conducted in that continent. Recent national statistics suggest that Chile may now have the highest reported cesarean section rate in the world. This paper examines cesarean birth trends in Chile with reference to changing patterns in health care financing.

Methods:

The growth in the national cesarean birth rate is analyzed, with reference to regional patterns, differences according to insurance coverage, and recent shifts in the financing pattern of health care provision, using insurance fund data and hospital reporting systems data for both public and private sector care from the mid‐1980s to mid‐1990s.

Results:

Chile had a cesarean birth rate of 37.2 percent for the 301,955 births covered by either the National Health Fund or private health insurance in 1994. This was a one‐third increase from the 1986 rate of 27.7 percent. The private health insurance sector revealed consistently far higher cesarean section rates than the National Health Fund sector (59% vs 28.8% in 1994); intrasectoral rates remained fairly stable over the 8‐year period.

Conclusions:

The overall increase in Chile's cesarean section rate correlates with the growth in the proportion of all births whose care was privately insured during these years (from 7.5% to 24.8%). This change may be partly explained by the doubling (to 32%) of the percentage of women with a personal obstetrician rather than a “duty” practitioner attending the birth of their baby. (BIRTH 24:4, December 1997)
Familial Lennox‐Gastaut syndrome in male siblings with a novel DCX mutation and anterior pachygyria
Authors: Lawrence Kate M. , Mei Davide , Newton Mark R. , Leventer Richard J. , Guerrini Renzo , Berkovic Samuel F.
Published: August 2010

Lennox‐Gastaut syndrome (LGS) has numerous causes, but only rarely has familial recurrence been observed. We studied a family in which three male members had severe epilepsy and intellectual disability. The proband had seizure onset at 7 years of age with atonic, myoclonic, atypical absence, and tonic seizures with slow spike‐wave on electroencephalography (EEG). One living sibling had a similar clinical pattern. One deceased sibling was known to have had seizures with intellectual disability. Neuroimaging revealed anterior predominant pachygyria. DNA sequencing of the gene doublecortin (DCX) on the X chromosome revealed a novel missense mutation in the two living affected male siblings. The occurrence of three affected male family members with proven or suspected LGS in this family was puzzling and only solved by a combination of magnetic resonance (MR) and molecular genetics evaluations. This finding provided essential information for genetic counseling.
An exploratory randomized controlled trial of immediate versus delayed withdrawal of antiepileptic drugs in patients with psychogenic nonepileptic attacks (PNEAs)
Authors: Oto Maria , Espie Colin A. , Duncan Roderick
Published: August 2010

Purpose:  To determine whether withdrawal of antiepileptic drugs (AEDs) in patients with psychogenic nonepileptic attacks (PNEAs) improves outcome.

Methods:  Randomized controlled trial of AED withdrawal in patients with PNEAs. Patients were randomized to immediate or delayed (9 months) withdrawal of AEDs. We recorded spell frequency, changes in work status, use of emergency medical services, and psychological status at baseline, 9 months, and 18 months.

Results:  Of 193 patients screened, 38 fulfilled entry criteria, 13 declined participation, and 25 were randomized. Fourteen patients were randomized to immediate withdrawal (IW) and 11 patients to delayed withdrawal (DW). There was a significant reduction in spell frequency from baseline to 9 months in the IW group but not in the DW group (p = 0.028). There was a significantly greater reduction in use of rescue medication in the IW group compared to the DW group between baseline and 9 months (p = 0.002). Emergency health care utilization dropped to zero in both groups by the end of the study. Psychological measures reflecting internal locus of control increased significantly more in the IW group (p = 0.005).

Discussion:  Stringent diagnostic criteria and an increasing tendency for patients to be referred before AED prescription limited the recruitment and the power of the study. Our data nonetheless provide evidence that some outcomes are improved by AED withdrawal in patients with PNEAs.
Continuous local intrahippocampal delivery of adenosine reduces seizure frequency in rats with spontaneous seizures
Authors: Van Dycke Annelies , Raedt Robrecht , Dauwe Ine , Sante Tom , Wyckhuys Tine , Meurs Alfred , Vonck Kristl , Wadman Wytse , Boon Paul
Published: August 2010

Purpose:  Despite different treatment options for patients with refractory epilepsy such as epilepsy surgery and neurostimulation, many patients still have seizures and/or drug‐related cerebral and systemic side effects. Local intracerebral delivery of antiepileptic compounds may represent a novel strategy with specific advantages such as the option of higher local doses and reduced side effects. In this study we evaluate the antiepileptic effect of local delivery of adenosine in the kainic acid rat model, a validated model for temporal lobe epilepsy.

Methods:  Fifteen rats, in which intraperitoneal kainic acid injection had induced spontaneous seizures, were implanted with a combination of depth electrodes and a cannula in both hippocampi. Cannulas were connected to osmotic minipumps to allow continuous hippocampal delivery. Rats were freely moving and permanently monitored by video‐EEG (electroencephalography). Seizures were scored during 2 weeks of local hippocampal delivery of saline (baseline), followed by 2 weeks of local adenosine (6 mg/ml) (n = 10) or saline (n = 5) delivery (0.23 μl/h) (treatment). In 7 of 10 adenosine‐treated rats, saline was also delivered during a washout period.

Results:  During the treatment period a mean daily seizure frequency reduction of 33% compared to the baseline rate was found in adenosine‐treated rats (p < 0.01). Four rats had a seizure frequency reduction of at least 50%. Both nonconvulsive and convulsive seizures significantly decreased during the treatment period. In the saline‐control group, mean daily seizure frequency increased with 35% during the treatment period.

Conclusions:  This study demonstrates the antiseizure effect of continuous adenosine delivery in the hippocampi in rats with spontaneous seizures.
The Veterans Administration's Comparison Study: Alcoholism and Drug Abuse—Combined and Conventional Treatment Settings
Authors: Baker Stewart L. , Lorei Theodore , McKnight Harry A. , Duvall Jeffrey L.
Published: August 2010

Traditionally, alcohol and drug abusers have been treated in separate environments. However, due to a growing interest in combined treatment, a 6‐mo comparison of patient performance obtained in conventional and combined treatment settings was carried out. While both treatment settings produced sizable improvements in patients, results indicated an improved outcome for alcoholics treated in a conventional setting which, though small, was statistically significant.
Ethics of Record‐Keeping
Authors: Blume Sheila B.
Published: August 2010

In light of modern advances in computer technology and the advent of third‐party payments for health care, measures must be taken to assure confidentiality of health records. However, this stress on confidentiality is in no way contrary to efforts to bring alcoholism into the light of public awareness.
Management of Alcoholism Programs Through a Computerized Information System
Authors: Paredes Alfonso
Published: August 2010

With the assistance of an information system (developed by the Oklahoma Department of Mental Health), evaluation becomes a dynamic process conducted without intruding into the organization and operation of the alcoholism treatment programs.
Alcoholism Treatment Programming: Historical Trends and Modern Approaches
Authors: Costello Raymond M. , Biever Paul , Baillargeon Jacques G.
Published: August 2010

Based on an investigation of the literature from 1951 to 1975, it can be generalized that alcoholism programs featuring multiple treatment components and dealing with a patient class of good prognosis might be expected to achieve a 50% success rate at l‐yr follow‐up, in contrast to programs with limited resources and poor‐prognosis patients, which can expect a success rate of only 15%.
Practical Experiences in Treatment Evaluation Through Follow‐Up Studies
Authors: Levinson Toby
Published: August 2010

The difficulties confronting the investigator evaluating alcoholism treatment programs are outlined, and two studies designed to take these problems into account are described. In one study, after 5 yr posttreatment, 115 of the original 154 subjects were successfully contacted and reassessed once again.
Acute Metabolic Interactions Between Ethanol and Cannabis
Authors: Siemens Albert J. , Khanna Jatinder M.
Published: August 2010

THC enhanced the depressant action of ethanol while CBD had no effect. Ethanol reduced THC brain and Mood levels but did not apparently change THC metabolism. THC and CBD did not inhibit the metabolism of ethanol.
Cognitive Deficits in Alcoholic Women
Authors: Hatcher Elizabeth M. , Jones Marilyn K. , Jonas Ben Morgan
Published: August 2010

A group of alcoholic women was compared to a matched group of nonalcoholic women on several cognitive tasks. Alcoholic women were impaired on both a spatial and a verbal abstracting test and were significantly more neurotic than the control women. The menstrual status of the women proved to be important when comparing the two groups.
The Effect of Cyanamide on Acetaldehyde Oxidation by Isolated Rat Liver Mitochondria and on the Inhibition of Pyruvate Oxidation by Acetaldehyde
Authors: Cederbaum Arthur I.
Published: August 2010

Compared to other substrates, the oxidation of pyruvate by isolated mitochondria is especially sensitive to inhibition by acetaldehyde. It is not known whether this inhibition represents a direct effect of acetaldehyde or requires the metabolism of acetaldehyde. Experiments were therefore carried out in the presence of cyanamide, an inhibitor of aldehyde dehydrogenase. After a brief incubation period, cyanamide inhibited the state 4 and state 3 rate of acetaldehyde (0.1–1.0 mM) oxidation by isolated rat liver mitochondria. Little inhibition was found in the absence of the incubation period. Maximum inhibition was found at cyanamide concentrations of 0.01 to 0.033 mM. Cyanamide also inhibited the activity of aldehyde dehydrogenase assayed in disrupted mitochondrial fractions. The inhibition by cyanamide was specific since cyanamide did not affect mitochondrial oxidation of succinate, glutamate, or pyruvate. Acetaldehyde inhibited the state 3 rate of pyruvate oxidation by liver mitochondria. Despite preventing acetaldehyde oxidation, cyanamide did not prevent the inhibition of pyruvate oxidation by acetaldehyde. These results indicate that (a) cyanamide can be used as an effective in vitro inhibitor of acetaldehyde oxidation and (b) the unique sensitivity of pyruvate oxidation to acetaldehyde represents a direct effect of acetaldehyde on pyruvate dehydrogenase.
The Differential Response of Tissue Catalase Activity to Chronic Alcohol Administration in the Rat
Authors: DeMaster Eugene G. , Kaplan Eli , Chesler Elliot
Published: August 2010

Sprague‐Dawley male rats maintained on the Lieber/ DeCarli liquid alcohol diet for 40 days showed an increase in heart, decrease in liver, and no change in erythrocyte or skeletal muscle catalase levels when compared to pair‐fed controls.
The Cardiovascular Effects of Ethanol and Acetaldehyde in Exercising Dogs
Authors: Stratton Ron , Dormer K. J. , Zeiner A. R.
Published: August 2010

The cardiovascular effects of ethanol and acetaldehyde were investigated in five dogs chronically instrumented to record heart rate, left ventricular peak systolic pressure, dP/dt max, left circumflex coronary artery blood flow, coronary sinus oxygen saturation, and myocardial oxygen consumption during a regulated exercise treadmill test.
Maternal Ethanol Consumption and Fetal Development in the Rat: A Comparison of Ethanol Exposure Techniques
Authors: Samson Herman H.
Published: August 2010

Comparison of the polydipsia and liquid diet procedures for ethanol exposure were used in female rats, either before and/or during gestation. Autopsy of the fetuses on day 20 of gestation found a significant weight reduction in the polydipsia‐exposed animals that could be attributed to ethanol. No such effect was found in the liquid diet‐exposed animals. The data are discussed in relation to the human fetal alcohol syndrome.
The Effect of Ethanol on Lipoprotein Metabolism
Authors: Robinson Stuart F. , Quarfordt Steven H.
Published: August 2010

A major effect of ethanol on lipoprotein metabolism is the development of hypertriglyceridemia. Triglyceride‐rich lipoproteins are secreted by the liver and intestine and undergo a two‐stage sequential catabolism–first in peripheral tissues, and second in the liver–mediated in part by the associated apolipoproteins. The argments for increased very low density lipoprotein production as an explanation for the hypertriglyceridemia are reviewed and found to be unconvincing. Experiments investigating the catabolism of chylomicrons are conflicting but appear on balance to suggest a catabolic defect. A potential relationship between plasma triglyceride‐rich lipoprotein metabolism and hepatic steatosis is considered. The lack of knowledge of the status of apolipoproteins in the setting of ethanol precludes definite conclusions, but defects in the incorporation or dissociation of the apolipoproteins on the triglyceride‐rich lipoproteins could explain some of the ethanol‐induced metabolic derangements.
Effect of Ethanol on Formation of Bile
Authors: Strasberg S. M.
Published: August 2010

The effects of ethanol on bile formation have been studied in the rat, dog, and man, in both acute and chronic models. The acute and chronic effects differ. Given acutely, ethanol suppresses bile flow and bile acid secretion rate. Chronic administration appears to increase both components of canalicular flow and bile acid secretion rate. Intestinal and hepatic actions are probably involved in the latter effect. Secretion of other biliary lipids and diagnostic anions are also reduced by ethanol.
Model Uncertainty and Risk Estimation for Experimental Studies of Quantal Responses
Authors: Bailer A. John , Noble Robert B. , Wheeler Matthew W.
Published: August 2010

Experimental animal studies often serve as the basis for predicting risk of adverse responses in humans exposed to occupational hazards. A statistical model is applied to exposure‐response data and this fitted model may be used to obtain estimates of the exposure associated with a specified level of adverse response. Unfortunately, a number of different statistical models are candidates for fitting the data and may result in wide ranging estimates of risk. Bayesian model averaging (BMA) offers a strategy for addressing uncertainty in the selection of statistical models when generating risk estimates. This strategy is illustrated with two examples: applying the multistage model to cancer responses and a second example where different quantal models are fit to kidney lesion data. BMA provides excess risk estimates or benchmark dose estimates that reflects model uncertainty.
A Multilayered Box Model for Calculating Preliminary Remediation Goals in Soil Screening
Authors: Shan Chao , Javandel Iraj
Published: August 2010

In the process of screening a soil against a certain contaminant, we define the health‐risk‐based preliminary remediation goal (PRG) as the contaminant concentration above which some remedial action may be required. Thus, PRG is the first standard (or guidance) for judging a site. An overestimated PRG (a too‐large value) may cause us to miss some contaminated sites that can threaten human health and the environment. An underestimated PRG (a too‐small value), on the other hand, may lead to unnecessary cleanup and waste tremendous resources. The PRGs for soils are often calculated on the assumption that the contaminant concentration in soil does not change with time. However, that concentration usually decreases with time as a result of different chemical and transport mechanisms. The static assumption thus exaggerates the long‐term exposure dose and results in a too‐small PRG. We present a box model that considers all important transport processes and obeys the law of mass conservation. We can use the model as a tool to estimate the transient contaminant concentrations in air, soil, and ground water. Using these concentrations in conjunction with appropriate health‐risk parameters, we may estimate the PRGs for different contaminants. As an example, we calculated the tritium PRG for residential soils. The result is quite different from, but within the range of, the two versions of the corresponding PRG previously recommended by the U.S. EPA.
A Screening Methodology for the Identification and Ranking of Infrastructure Vulnerabilities Due to Terrorism
Authors: Apostolakis George E. , Lemon Douglas M.
Published: August 2010

The extreme importance of critical infrastructures to modern society is widely recognized. These infrastructures are complex and interdependent. Protecting the critical infrastructures from terrorism presents an enormous challenge. Recognizing that society cannot afford the costs associated with absolute protection, it is necessary to identify and prioritize the vulnerabilities in these infrastructures. This article presents a methodology for the identification and prioritization of vulnerabilities in infrastructures. We model the infrastructures as interconnected digraphs and employ graph theory to identify the candidate vulnerable scenarios. These scenarios are screened for the susceptibility of their elements to a terrorist attack, and a prioritized list of vulnerabilities is produced. The prioritization methodology is based on multiattribute utility theory. The impact of losing infrastructure services is evaluated using a value tree that reflects the perceptions and values of the decisionmaker and the relevant stakeholders. These results, which are conditional on a specified threat, are provided to the decisionmaker for use in risk management. The methodology is illustrated through the presentation of a portion of the analysis conducted on the campus of the Massachusetts Institute of Technology.
Aggregate, Disaggregate, and Hybrid Analyses of Ecological Risk Perceptions
Authors: Willis Henry H. , DeKay Michael L. , Fischhoff Baruch , Morgan M. Granger
Published: August 2010

Laypeople's perceptions of health and safety risks have been widely studied, but only a few studies have addressed perceptions of ecological hazards. We assembled a list of 39 attributes of ecological hazards from the literatures on comparative risk assessment, ecological health, environmental conservation and management, environmental psychology, and risk perception. In Study 1, 125 laypeople evaluated 83 hazards on subsets of this attribute set. Factor analysis of attribute ratings (averaged over participants) revealed six oblique factors: ecological impacts, human impacts, human benefits, aesthetic impacts, scientific understanding, and controllability. These factors predicted mean judgments of overall riskiness, ecological riskiness, acceptability, and regulatory strictness. In Study 2, 30 laypeople each evaluated 34 hazards on 17 attributes and 3 dependent variables. Aggregate‐level factor analysis of these data replicated the appropriate portion of the factor solution and yielded similar regression results. Parallel analyses at the individual‐participant level yielded factors that explained less variance in judgments of overall riskiness, ecological riskiness, and acceptability. However, the decrease in explanatory power was much less than is often reported for disaggregate‐level analyses of psychometric data. This discrepancy illustrates the importance of distinguishing between the level of analysis (aggregate versus disaggregate) and the focus of analysis (distinctions among hazards versus distinctions among participants). In a hybrid analysis, aggregate‐level factor scores predicted individual participants' riskiness judgments reasonably well. Psychometric studies such as these provide a sound empirical basis for selecting attributes of ecological hazards for use in comparative risk assessment.
Analyzing BSE Transmission to Quantify Regional Risk
Authors: De Koeijer Aline A.
Published: August 2010

As a result of consumer fears and political concerns related to BSE as a risk to human health, a need has arisen recently for more sensitive methods to detect BSE and more accurate methods to determine BSE incidence. As a part of the development of such methods, it is important to be able to identify groups of animals with above‐average BSE risk. One of the well‐known risk factors for BSE is age, as very young animals do not develop the disease, and very old animals are less likely to develop the disease. Here, we analyze which factors have a strong influence on the age distribution of BSE in a population. Building on that, we develop a simple set of calculation rules for classifying the BSE risk in a given cattle population. Required inputs are data on imports and on the BSE control measures in place over the last 10 or 20 years.
Quantitative Risk Assessment for Bovine Spongiform Encephalopathy in Low‐ or Zero‐Prevalence Countries: The Example of Norway
Authors: Hogasen Helga Rachel , De Koeijer Aline A.
Published: August 2010

A predictive case‐cohort model is applied to Norwegian data to analyze the interaction between challenge and stability factors for bovine spongiform encephalopathy (BSE) during the period 1980–2010. For each year, the BSE risk in cattle is estimated as the expected number of cases. The age distribution of expected cases as well as the relative impact of different challenges is estimated. The model consists of a simple, transparent, and practical deterministic spreadsheet calculation model, in which the following country‐specific inputs are entered: (i) annual imports of live cattle and meat and bone meal, (ii) age distribution of native cattle, and (iii) estimated annual basic reproduction ratio (R0) for BSE. Results for Norway indicate that the highest risk of BSE cases was in 1989, when a total BSE risk of 0.13 cases per year was expected. After that date, the year‐to‐year decrease in risk ranged between 3% and 47%, except for a secondary peak in 1994 at 0.06 cases per year. The primary peak was almost entirely (99%) attributable to the importation of 11 cattle from the United Kingdom between 1982 and 1986. The secondary peak, in 1994, originated mainly from the recycling of the U.K. imported cattle (92%). In 2006, the remaining risk was 0.0003 cases per year, or 0.001 per million cows per year, with a maximal age‐specific incidence of 0.03 cases per million per year in 10‐year‐old cattle. Only 15% of the cases were expected in imported cattle. The probability of having zero cases in Norway in 2006 was estimated to be 99.97%. The model and results are compared to previous risk assessments of Norway by the EU.
Complementary Approach of Data Analysis and Modeling to Estimate the Pattern of the BSE Epidemic: The Example of France
Authors: Calavas Didier , Supervie V. , Morignat E. , Costagliola D. , Ducrot C.
Published: August 2010

Clinical surveillance was the only way to detect bovine spongiform encephalopathy (BSE) until July 2000 in France. From the 103 cases identified as such between 1991 and June 2000, we used a back‐calculation method to reconstruct the longitudinal trend of BSE infections. Between July 1987 and June 1997, an estimated 51,300 (CI =[24,300–84,700]) cattle were infected in France. The comprehensive surveillance of BSE with rapid tests, set up in France since 2001 at the abattoir and fallen plant, allowed study of the relative exposure of the successive birth cohorts with nonconditional logistic regression models adjusted for possible confounding variables. The results were in agreement with those of the back‐calculation model, estimating a decrease of the BSE exposure from the birth cohort July 1995–June 1996 that matched with the decrease of the infection after June 1996. In view of the long incubation period of BSE, it is not possible to precisely assess the impact of any control measure before several years. Modeling was therefore used to estimate prospectively the efficiency of the ban of meat and bone meal extended to all farm species in November 2000. Using parameters about age at infection and incubation time estimated earlier, we assessed the minimum time to first detection if infections still occurred. We have waited up to June 2007 to know if less than 100 infections occurred among French cattle during the 6 months following January 2001.
Comparison of the Historic Recycling Risk for BSE in Three European Countries by Calculating the Basic Reproduction Ratio R0
Authors: Schwermer Heinzpeter , De Koeijer Aline , Brülisauer Franz , Heim Dagmar
Published: August 2010

A deterministic model of BSE transmission is used to calculate the R0values for specific years of the BSE epidemics in the United Kingdom (UK), the Netherlands (NL), and Switzerland (CH). In all three countries, the R0values decreased below 1 after the introduction of a ban on feeding meat and bone meal (MBM) to ruminants around the 1990s. A variety of additional measures against BSE led to further decrease of R0to about 0.06 in the years around 1998. The calculated R0values were consistent with the observations made on the surveillance results for UK, but were partially conflicting with the surveillance results for NL and CH. There was evidence for a dependency of the BSE epidemic in NL and CH from an infection source not considered in the deterministic transmission model. Imports of MBM and feed components can be an explanation for this discrepancy, and the importance of imports for these observations is discussed.
Assessment of Inhalation Exposures and Potential Health Risks to the General Population that Resulted from the Collapse of the World Trade Center Towers
Authors: Lorber Matthew , Gibb Herman , Grant Lester , Pinto Joseph , Pleil Joachim , Cleverly David
Published: August 2010

In the days following the collapse of the World Trade Center (WTC) towers on September 11, 2001 (9/11), the U.S. Environmental Protection Agency (EPA) initiated numerous air monitoring activities to better understand the ongoing impact of emissions from that disaster. Using these data, EPA conducted an inhalation exposure and human health risk assessment to the general population. This assessment does not address exposures and potential impacts that could have occurred to rescue workers, firefighters, and other site workers, nor does it address exposures that could have occurred in the indoor environment. Contaminants evaluated include particulate matter (PM), metals, polychlorinated biphenyls, dioxins, asbestos, volatile organic compounds, particle‐bound polycyclic aromatic hydrocarbons, silica, and synthetic vitreous fibers (SVFs). This evaluation yielded three principal findings. (1) Persons exposed to extremely high levels of ambient PM and its components, SVFs, and other contaminants during the collapse of the WTC towers, and for several hours afterward, were likely to be at risk for acute and potentially chronic respiratory effects. (2) Available data suggest that contaminant concentrations within and near ground zero (GZ) remained significantly elevated above background levels for a few days after 9/11. Because only limited data on these critical few days were available, exposures and potential health impacts could not be evaluated with certainty for this time period. (3) Except for inhalation exposures that may have occurred on 9/11 and a few days afterward, the ambient air concentration data suggest that persons in the general population were unlikely to suffer short‐term or long‐term adverse health effects caused by inhalation exposures. While this analysis by EPA evaluated the potential for health impacts based on measured air concentrations, epidemiological studies conducted by organizations other than EPA have attempted to identify actual impacts. Such studies have identified respiratory effects in worker and general populations, and developmental effects in newborns whose mothers were near GZ on 9/11 or shortly thereafter. While researchers are not able to identify specific times and even exactly which contaminants are the cause of these effects, they have nonetheless concluded that exposure to WTC contaminants (and/or maternal stress, in the case of developmental effects) resulted in these effects, and have identified the time period including 9/11 itself and the days and few weeks afterward as a period of most concern based on high concentrations of key pollutants in the air and dust.
Reducing the Risk of Human Extinction
Authors: Matheny Jason G.
Published: August 2010

In this century a number of events could extinguish humanity. The probability of these events may be very low, but the expected value of preventing them could be high, as it represents the value of all future human lives. We review the challenges to studying human extinction risks and, by way of example, estimate the cost effectiveness of preventing extinction‐level asteroid impacts.
On Determining Specifications and Selections of Alternative Technologies for Airport Checked‐Baggage Security Screening
Authors: Feng Qianmei
Published: August 2010

Federal law mandates that every checked bag at all commercial airports be screened by explosive detection systems (EDS), explosive trace detection systems (ETD), or alternative technologies. These technologies serve as critical components of airport security systems that strive to reduce security risks at both national and global levels. To improve the operational efficiency and airport security, emerging image‐based technologies have been developed, such as dual‐energy X‐ray (DX), backscatter X‐ray (BX), and multiview tomography (MVT). These technologies differ widely in purchasing cost, maintenance cost, operating cost, processing rate, and accuracy. Based on a mathematical framework that takes into account all these factors, this article investigates two critical issues for operating screening devices: setting specifications for continuous security responses by different technologies; and selecting technology or combination of technologies for efficient 100% baggage screening. For continuous security responses, specifications or thresholds are used for classifying threat items from nonthreat items. By investigating the setting of specifications on system security responses, this article assesses the risk and cost effectiveness of various technologies for both single‐device and two‐device systems. The findings provide the best selection of image‐based technologies for both single‐device and two‐device systems. Our study suggests that two‐device systems outperform single‐device systems in terms of both cost effectiveness and accuracy. The model can be readily extended to evaluate risk and cost effectiveness of multiple‐device systems for airport checked‐baggage security screening.
Water Quality Failures in Distribution Networks—Risk Analysis Using Fuzzy Logic and Evidential Reasoning
Authors: Sadiq Rehan , Kleiner Yehuda , Rajani Balvant
Published: August 2010

The evaluation of the risk of water quality failures in a distribution network is a challenging task given that much of the available data are highly uncertain and vague, and many of the mechanisms are not fully understood. Consequently, a systematic approach is required to handle quantitative‐qualitative data as well as a means to update existing information when new knowledge and data become available. Five general pathways (mechanisms) through which a water quality failure can occur in the distribution network are identified in this article. These include contaminant intrusion, leaching and corrosion, biofilm formation and microbial regrowth, permeation, and water treatment breakthrough (including disinfection byproducts formation). The proposed methodology is demonstrated using a simplified example for water quality failures in a distribution network. This article builds upon the previous developments of aggregative risk analysis approach. Each basic risk item in a hierarchical framework is expressed by a triangular fuzzy number, which is derived from the composition of thelikelihoodof a failure event and the associated failureconsequence. An analytic hierarchy process is used to estimate weights required for grouping noncommensurate risk sources. The evidential reasoning is proposed to incorporate newly arrived data for the updating of existing risk estimates. The exponential ordered weighted averaging operators are used for defuzzification to incorporate attitudinal dimension for risk management. It is envisaged that the proposed approach could serve as a basis to benchmark acceptable risks in water distribution networks.
What Risks Do People Perceive in Everyday Life? A Perspective Gained from the Experience Sampling Method (ESM)
Authors: Hogarth Robin M. , Portell Mariona , Cuxart Anna
Published: August 2010

Theexperience sampling method(ESM) was used to collect data from 74 part‐time students who described and assessed the risks involved in their current activities when interrupted at random moments by text messages. The major categories of perceived risk were short term in nature and involved “loss of time or materials” related to work and “physical damage” (e.g., from transportation). Using techniques of multilevel analysis, we demonstrate effects of gender, emotional state, and types of risk on assessments of risk. Specifically, females do not differ from males in assessing the potential severity of risks but they see these as more likely to occur. Also, participants assessed risks to be lower when in more positive self‐reported emotional states. We further demonstrate the potential of ESM by showing that risk assessments associated with current actions exceed those made retrospectively. We conclude by noting advantages and disadvantages of ESM for collecting data about risk perceptions.
Symmetry, Identifiability, and Prediction Uncertainties in Multistage Clonal Expansion (MSCE) Models of Carcinogenesis
Authors: Cox Louis Anthony , Huber William A.
Published: August 2010

Many models of exposure‐related carcinogenesis, including traditional linearized multistage models and more recent two‐stage clonal expansion (TSCE) models, belong to a family of models in which cells progress between successive stages—possibly undergoing proliferation at some stages—at rates that may depend (usually linearly) on biologically effective doses. Biologically effective doses, in turn, may depend nonlinearly on administered doses, due to PBPK nonlinearities. This article provides an exact mathematical analysis of the expected number of cells in the last (“malignant”) stage of such a “multistage clonal expansion” (MSCE) model as a function of dose rate and age. The solution displays symmetries such that several distinct sets of parameter values provide identical fits to all epidemiological data, make identical predictions about the effects on risk of changes in exposure levels or timing, and yet make significantly different predictions about the effects on risk of changes in the composition of exposure that affect the pharmacodynamic dose‐response relation. Several different predictions for the effects of such an intervention (such as reducing carcinogenic constituents of an exposure) that acts on only one or a few stages of the carcinogenic process may be equally consistent with all preintervention epidemiological data. This is an example of nonunique identifiability of model parameters and predictions from data. The new results on nonunique model identifiability presented here show that the effects of an intervention on changing age‐specific cancer risks in an MSCE model can be either large or small, but that which is the case cannot be predicted from preintervention epidemiological data and knowledge of biological effects of the intervention alone. Rather, biological data that identify which rate parameters hold for which specific stages are required to obtain unambiguous predictions. From epidemiological data alone, only a set of equally likely alternative predictions can be made for the effects on risk of such interventions.
Analysis of the Treatment, by the U.S. Department of Energy, of the FEP Hydrothermal Activity in the Yucca Mountain Performance Assessment
Authors: Dublyansky Yuri
Published: August 2010

The U.S. Code of Federal Regulations, 10 CFR Part 63, stipulates that the expected performance of the geological high‐level nuclear waste repository must be demonstrated through a total system performance assessment (TSPA). The TSPA represents an analysis that identifies all features, events, and processes (FEPs) that might affect the disposal system and examines the effects of the identified FEPs upon the performance of the system. Secondary minerals from the thick unsaturated zone of Yucca Mountain were deposited from waters with temperatures up to 70–90°C. U‐Pb dating constrained the ages of the elevated temperatures to the period between 10 and 5–6 million years ago. Relatively youthful circulation of thermal waters (hydrothermal activity) would be of concern for the safety of the disposal facility. A phenomenological model was advanced by the U.S. Department of Energy (DOE), which proposed that the minerals were deposited by infiltrating meteoric waters that were heated upon contact with the bedrock; it was hypothesized that the latter was conductively heated by a shallow silicic magma body. The model rendered processes responsible for elevated water temperatures inconsequential for the safety of the proposed nuclear waste facility. However, attempts by DOE at validating the model by means of numeric thermal simulations and analogue system observations were unsuccessful. Regulations specify two criteria for exclusion of a FEP from consideration in the TSPA: low probability and low consequence. The lack of a plausible phenomenological model makes it impossible to apply either of these two criteria to the FEP Hydrothermal Activity. Despite the lack of a valid criterion for exclusion, it was excluded from the TSPA. Both the development of DOE's thermal model and the formal FEP analysis were associated with deviations from DOE's quality assurance regulations.