bluuebunny/crossref_metadata_2025 huggingface dataset:
A bradoriid and brachiopod dominated shelly fauna from the Furongian (Cambrian) of Västergötland, Sweden
Authors: Topper Timothy P. , Skovsted Christian B. , Harper David A. T. , Ahlberg Per
Published: January 2013

A small assemblage of shelly fossils, dominated by the brachiopodTreptotreta jucundaand the bradoriid arthropodMongolitubulus aspermachaeranew species is described from a Furongian limestone of Västergötland, south-central Sweden.Mongolitubulus aspermachaerais represented in the assemblage by individual valves and numerous, ornamented spines. Valves and spines share identical ornament and microstructure leaving no doubt that the isolated spines were once attached to the bradoriid valves.Mongolitubulus aspermachaeraadds to the increasing list of spinose Cambrian bradoriid arthropods, and Mongolitubulidae new family is erected here to incorporate the generaMongolitubulus,TubuteriumandSpinospitella. Mongolitubulus aspermachaerarepresents the youngest member of the new family and supplements the biodiversity of bradoriids in the Furongian, an interval when bradoriid diversity is considered to be very much on the decline. The brachiopodTreptotreta jucundadescribed predominantly from the ‘middle' to ‘late' Cambrian of Australia is here documented for the first time from outside Gondwana, dramatically extending the biogeographical range of the species. Other elements of the faunal assemblage include typical Baltic Furongian representatives, such as the trilobiteParabolina, the agnostoidAgnostusand the phosphatocopidsHesslandonaandVestrogothia.
A diverse new assemblage of green lacewings (Insecta, Neuroptera, Chrysopidae) from the early Eocene Okanagan Highlands, western North America
Authors: Makarkin Vladimir N. , Archibald S. Bruce
Published: January 2013

The early Eocene green lacewings (Neuroptera, Chrysopidae) of the Okanagan Highlands deposits of McAbee, and Driftwood Canyon, British Columbia (Canada) and Republic, Washington (U.S.A.) are treated in detail for the first time. At least six genera are present, one unnamed, three new, with at least 10 new species, six named:Protochrysa fuscobasalisn. sp. (McAbee) (Limaiinae, the youngest known record of the subfamily),Okanaganochrysa coltsunaen. gen. n. sp. (McAbee),Adamsochrysa asperan. gen. n. sp. (McAbee),A. wilsonin. gen. n. sp. (Republic),Archaeochrysa profractan. sp. (McAbee), andPseudochrysopa harveyin. gen. n. sp. (Driftwood Canyon) (all Nothochrysinae, the latter provisionally). The four unnamed species include one assigned toPseudochrysopa, two likely belonging toAdamsochrysa, and one of an unknown nothochrysine genus. Microtholi are detected on the abdominal sclerites ofAdamsochrysa wilsoni, and the spermatheca and spermathecal duct in the abdomen ofPseudochrysopa harveyi, the first reported occurrences of these preserved in fossil Chrysopidae. Structures were detected on the apical wing margins of some species that appear similar to trichosors, which are unknown in Chrysopidae, but are present in some other neuropteran families. This is the richest described assemblage of the family anywhere in the fossil record. Okanagan chrysopids were also morphologically and presumably ecologically diverse, including large species with rich venation and well as those with simplified venation and the smallest known fossil species. This is the oldest reported occurrence of the family in North America.
Fossil mayfly larvae (Ephemeroptera, cf. Heptageniidae) from the Late Cretaceous Wapiti Formation, Alberta, Canada
Authors: Bell Phil R. , Fanti Federico , Acorn John , Sissons Robin S.
Published: January 2013

Fossil mayfly larvae (cf. Heptageniidae) are reported for the first time in the Cretaceous of Canada. The new fossils come from the latest Campanian part of the Wapiti Formation, which crops out in west-central Alberta, near the British Columbia border. These sediments represent mixed lentic and lotic fluvial environments consistent with modern heptageniid ecology. This discovery helps fill a significant temporal gap in heptageniid evolution between the Eocene and their earliest appearance in the Turonian.
Alaskodiscus, a new name for the Ordovician bellerophontoidean gastropod Alaskadiscus Rohr, Frýda and Blodgett, 2003
Authors: Rohr David M. , Frýda Jiří , Blodgett Robert B.
Published: January 2013

The Late Ordovician tropidodiscid gastropod Alaskadiscus, known only in two areas in Alaska, was named by Rohr, Frýda, and Blodgett (2003). Peter Wagner and Stephen K. Donovan have pointed out to us that the name was previously used for a Cambrian trilobite, Alaskadiscus Zhang, 1980. We propose the new name Alaskodiscus with the same type species, A. donensis Rohr, Frýda and Blodgett, 2003. We feel the similarity in names is not likely to cause undue confusion since the taxa are widely separated by phyla and age.
Day length, reproductive effort, and the avian latitudinal clutch size gradient
Authors: Rose Alexandra P. , Lyon Bruce E.
Published: January 2013

Explaining latitudinal patterns in life history traits remains a challenge for ecologists and evolutionary biologists. One such prominent pattern is the latitudinal gradient in clutch size in birds: the number of eggs laid in a reproductive bout increases with latitude in many species. One intuitive hypothesis proposes that the longer days at high latitudes during the breeding season allow parents to spend more time foraging each day, which results in greater total food delivery to the brood each day, and hence more offspring produced. This day length hypothesis is virtually untested, although it was proposed nearly 100 years ago. We developed a conceptual framework for distinguishing between the day length hypothesis and the widely accepted alternative hypothesis that attributes the latitudinal gradient in clutch size to increased per capita food resources at higher latitudes. Using this framework to contrast components of reproductive effort and life history patterns in a mid‐ and high‐latitude Tree Swallow (Tachycineta bicolor) population provided clear evidence for the day length hypothesis, but little evidence for the alternative. Our findings suggest that the length of an animal's workday may be an important, but unappreciated, component of reproductive effort.
Deer density and disease prevalence influence transmission of chronic wasting disease in white‐tailed deer
Authors: Storm Daniel J. , Samuel Michael D. , Rolley Robert E. , Shelton Paul , Keuler Nicholas S. , Richards Bryan J. , Van Deelen Timothy R.
Published: January 2013

Host‐parasite dynamics and strategies for managing infectious diseases of wildlife depend on the functional relationship between disease transmission rates and host density. However, the disease transmission function is rarely known for free‐living wildlife, leading to uncertainty regarding the impacts of diseases on host populations and effective control actions. We evaluated the influence of deer density, landscape features, and soil clay content on transmission of chronic wasting disease (CWD) in young (<2‐year‐old) white‐tailed deer (Odocoileus virginianus) in south‐central Wisconsin, USA. We evaluated how frequency‐dependent, density‐dependent, and intermediate transmission models predicted CWD incidence rates in harvested yearling deer. An intermediate transmission model, incorporating both disease prevalence and density of infected deer, performed better than simple density‐ and frequency‐dependent models. Our results indicate a combination of social structure, non‐linear relationships between infectious contact and deer density, and distribution of disease among groups are important factors driving CWD infection in young deer. The landscape covariates % deciduous forest cover and forest edge density also were positively associated with infection rates, but soil clay content had no measurable influences on CWD transmission. Lack of strong density‐dependent transmission rates indicates that controlling CWD by reducing deer density will be difficult. The consequences of non‐linear disease transmission and aggregation of disease on cervid populations deserves further consideration.
Gingival Crevicular Fluid, Serum Levels of Receptor Activator of Nuclear Factor‐κB Ligand, Osteoprotegerin, and Interleukin‐17 in Patients With Rheumatoid Arthritis and Osteoporosis and With Periodontal Disease
Authors: Gümüş Pınar , Buduneli Eralp , Bıyıkoğlu Başak , Aksu Kenan , Saraç Fulden , Nile Christopher , Lappin David , Buduneli Nurcan
Published: January 2013

Background: This study is performed to evaluate gingival crevicular fluid (GCF) and serum levels of soluble receptor activator of nuclear factor‐κB ligand (sRANKL), interleukin (IL)‐17A, IL‐17E, IL‐17F, IL‐17A/F, and osteoprotegerin (OPG) in women with rheumatoid arthritis (RA), osteoporosis (OPR), and those who are systemically healthy (SH), all with periodontal disease.

Methods: GCF and serum samples were obtained before any periodontal intervention from 17 women with RA, 19 with OPR, and 13 who were SH with periodontitis. Full‐mouth clinical periodontal measurements were recorded. sRANKL, OPG, and IL‐17 levels were determined by enzyme‐linked immunosorbent assay.

Results: Clinical periodontal measurements were similar in the three study groups. Although the total amounts of GCF albumin, OPG, IL‐17A, and IL‐17A/F were similar in the study groups, there were statistically significant differences in GCF concentrations of sRANKL, OPG, IL‐17A, IL‐17E, IL‐17F, and IL‐17A/F. The sRANKL/OPG ratios were significantly higher in the RA group than in the OPR and SH groups (P <0.05). Serum sRANKL, sRANKL/OPG, and IL‐17A/IL‐17E ratios were significantly higher, whereas OPG concentrations were significantly lower in the RA group compared to other groups (P <0.05). Serum IL‐17A concentrations were significantly higher in the RA and OPR groups than in the SH group (P <0.05).

Conclusion: Increased inflammatory mediator levels in patients with RA, despite the long‐term use of various anti‐inflammatory drugs, suggest that these patients may have a propensity to overproduce these inflammatory mediators.
Probiotic Therapy Reduces Periodontal Tissue Destruction and Improves the Intestinal Morphology in Rats With Ligature‐Induced Periodontitis
Authors: Messora Michel R. , Oliveira Luiz F.F. , Foureaux Renata C. , Taba Mario , Zangerônimo Márcio G. , Furlaneto Flávia A.C. , Pereira Luciano J.
Published: January 2013

Background: With increase in the incidence of resistance to antibiotics, probiotics are emerging as a promising adjunctive periodontal therapy. The authors of this study evaluate the influence of probiotic (PROB) supplementation on ligature‐induced periodontitis (LIP) and intestinal morphology in rats.

Methods: Thirty‐two rats were randomly divided into four groups: control (C), LIP, PROB, and LIP/PROB. In groups PROB and LIP/PROB, the PROB was administered orally by addition to the drinking water of the animals for 44 days. In groups LIP and LIP/PROB, the mandibular right first molar of the animals received a cotton ligature that was left in the same position for 14 days. All animals were euthanized 44 days after the start of the PROB supplementation. The jaws were resected and histomorphometric analyses were performed. The measurements included evaluation of attachment loss (AL) and alveolar bone level (ABL) on the distal root of the mandibular first molar. Samples of the duodenum, jejunum, and ileum were also dissected from each animal to evaluate the villous height (VH) and crypt depth (CD). The data obtained were subjected to statistical analyses (analysis of variance, Tukey; P <0.05).

Results: Mean values of AL and ABL were significantly higher in group LIP compared with group LIP/PROB (AL: 3.05 ± 0.57 mm and 1.78 ± 0.63 mm, respectively; ABL: 4.21 ± 0.42 mm and 3.38 ± 0.17 mm, respectively). In group LIP/PROB, the mean values of VH and CD of the jejunum were significantly higher than the ones from group LIP (VH: 672.1 ± 83.3 µm and 528.0 ± 51.7 µm, respectively; CD: 463.8 ± 100.9 µm and 269.0 ± 48.4 µm, respectively).

Conclusions: It can be concluded that PROB supplementation 1) reduces AL and alveolar bone loss in rats with LIP and 2) can protect the small intestine from reactive changes induced by LIP.
Risks of High-Powered Motorcycles Among Younger Adults
Authors: Rolison Jonathan J. , Hewson Paul J. , Hellier Elizabeth , Hurst Laura
Published: January 2013

Objectives. We assessed whether policies designed to safeguard young motorcyclists would be effective given shifts in ownership toward high-powered motorcycles.

Methods. We investigated population-wide motor vehicle driver and motorcyclist casualties (excluding passengers) recorded in Britain between 2002 and 2009. To adjust for exposure and measure individual risk, we used the estimated number of trips of motorcyclists and drivers, which had been collected as part of a national travel survey.

Results. Motorcyclists were 76 times more likely to be killed than were drivers for every trip. Older motorcyclist age—strongly linked to experience, skill set, and riding behavior—did not abate the risks of high-powered motorcycles. Older motorcyclists made more trips on high-powered motorcycles.

Conclusions: Tighter engine size restrictions would help reduce the use of high-powered motorcycles. Policymakers should introduce health warnings on the risks of high-powered motorcycles and the benefits of safety equipment.
Individual and Neighborhood Socioeconomic Status Effects on Adolescent Smoking: A Multilevel Cohort-Sequential Latent Growth Analysis
Authors: Mathur Charu , Erickson Darin J. , Stigler Melissa H. , Forster Jean L. , Finnegan John R.
Published: January 2013

Objectives. We examined the prospective effects of parental education (as a proxy for individual socioeconomic status [SES]) and neighborhood SES on adolescent smoking trajectories and whether the prospective effects of individual SES varied across neighborhood SES.

Methods. The study included 3635 randomly recruited adolescents from 5 age cohorts (12–16 years) assessed semiannually for 3 years in the Minnesota Adolescent Community Cohort study. We employed a cohort–sequential latent growth model to examine smoking from age 12 to 18 years with predictors.

Results. Lower individual SES predicted increased levels of smoking over time. Whereas neighborhood SES had no direct effect, the interaction between individual and neighborhood SES was significant. Among higher and lower neighborhood SES, lower individual SES predicted increased levels of smoking; however, the magnitude of association between lower individual SES and higher smoking levels was significantly greater for higher neighborhood SES.

Conclusions. We found evidence for differential effects of individual SES on adolescent smoking for higher and lower neighborhood SES. The group differences underscore social conditions as fundamental causes of disease and development of interventions and policies to address inequality in the resources.
Access to Oral Health Care: The Role of Federally Qualified Health Centers in Addressing Disparities and Expanding Access
Authors: Jones Emily , Shi Leiyu , Hayashi Arthur Seiji , Sharma Ravi , Daly Charles , Ngo-Metzger Quyen
Published: January 2013

Objectives. We examined utilization, unmet need, and satisfaction with oral health services among Federally Qualified Health Center patients. We examined correlates of unmet need to guide efforts to increase access to oral health services among underserved populations.

Methods. Using the 2009 Health Center Patient Survey, we performed multivariate logistic regressions to examine factors associated with access to dental care at health centers, unmet need, and patient experience.

Results. We found no racial or ethnic disparities in access to timely oral health care among health center patients; however, uninsured patients and those whose insurance does not provide dental coverage experienced restricted access and greater unmet need. Slightly more than half of health center patients had a dental visit in the past year, but 1 in 7 reported that their most recent visit was at least 5 years ago. Among health center patients who accessed dental care at their health center, satisfaction was high.

Conclusions. These results underscore the critical role that health centers play in national efforts to improve oral health status and eliminate disparities in access to timely and appropriate dental services.
Giving to Others and the Association Between Stress and Mortality
Authors: Poulin Michael J. , Brown Stephanie L. , Dillard Amanda J. , Smith Dylan M.
Published: January 2013

Objectives. We sought to test the hypothesis that providing help to others predicts a reduced association between stress and mortality.

Methods. We examined data from participants (n = 846) in a study in the Detroit, Michigan, area. Participants completed baseline interviews that assessed past-year stressful events and whether the participant had provided tangible assistance to friends or family members. Participant mortality and time to death was monitored for 5 years by way of newspaper obituaries and monthly state death-record tapes.

Results. When we adjusted for age, baseline health and functioning, and key psychosocial variables, Cox proportional hazard models for mortality revealed a significant interaction between helping behavior and stressful events (hazard ratio [HR] = 0.58; P < .05; 95% confidence interval [CI] = 0.35, 0.98). Specifically, stress did not predict mortality risk among individuals who provided help to others in the past year (HR = 0.96; 95% CI = 0.79, 1.18), but stress did predict mortality among those who did not provide help to others (HR = 1.30; P < .05; 95% CI = 1.05, 1.62).

Conclusions. Helping others predicted reduced mortality specifically by buffering the association between stress and mortality.
Young Adult Smoking Cessation: Predictors of Quit Attempts and Abstinence
Authors: Diemert Lori M. , Bondy Susan J. , Brown K. Stephen , Manske Steve
Published: January 2013

We examined young adult smoking cessation behaviors, coding cessation behavior as no attempt, quit attempt (< 30 days), or abstinence (≥ 30 days) during follow-up from July 2005 through December 2008, observed in 592 young adult smokers from the Ontario Tobacco Survey. One in 4 young adults made an attempt; 14% obtained 30-day abstinence. Cessation resources, prior attempts, and intention predicted quit attempts, whereas high self-efficacy, using resources, having support, and low addiction predicted abstinence, indicating that young adult smokers require effective and appropriate cessation resources.
Water Fluoridation and the Association of Sugar-Sweetened Beverage Consumption and Dental Caries in Australian Children
Authors: Armfield Jason M. , Spencer A. John , Roberts-Thomson Kaye F. , Plastow Katrina
Published: January 2013

Objectives. We examined demographic and socioeconomic differences in the consumption of sugar-sweetened beverages (SSBs), its association with dental caries in children, and whether exposure to water fluoridation modifies this association.

Methods. In a cross-sectional study, we used a stratified, clustered sampling design to obtain information on 16 508 children aged 5 to 16 years enrolled in Australian school dental services in 2002 to 2005. Dental staff assessed dental caries, and parents completed a questionnaire about their child’s residential history, sources of drinking water, toothbrushing frequency, socioeconomic status (SES), and SSB consumption.

Results. Children who brushed their teeth less often and were older, male, of low SES, from rural or remote areas consumed significantly more SSBs. Caries was significantly associated with greater SSB consumption after controlling for potential confounders. Finally, greater exposure to fluoridated water significantly reduced the association between children’s SSB consumption and dental caries.

Conclusions. Consumption of SSBs should be considered a major risk factor for dental caries. However, increased exposure to fluoridated public water helped ameliorate the association between SSB consumption and dental decay. These results reconfirm the benefits of community water fluoridation for oral health.
Fatty, Fatty, Two-by-Four: Weight-Teasing History and Disturbed Eating in Young Adult Women
Authors: Quick Virginia M. , McWilliams Rita , Byrd-Bredbenner Carol
Published: January 2013

Objective. We investigated the long-term effect of weight teasing during childhood.

Methods. Young adult women (n = 1533; aged 18–26 years) from 3 large universities participated in a survey (Fall 2009 to Spring 2010) that assessed disturbed eating behaviors; weight status at ages 6, 12, and 16 years; and weight-teasing history.

Results. Nearly half of the participants were weight-teased as a child. Participants who experienced childhood weight teasing were significantly more likely to have disturbed eating behaviors now than non–weight-teased peers. As the variety of weight teasing insults recalled increased, so did disturbed eating behaviors and current body mass index. Those who recalled their weight at ages 6, 12, or 16 years as being heavier than average endured weight teasing significantly more frequently and felt greater distress than their lighter counterparts.

Conclusions. Weight teasing may contribute to the development of disturbed eating and eating disorders in young women. Health care professionals, parents, teachers, and other childcare givers must help shift social norms to make weight teasing as unacceptable as other types of bullying. To protect the health of children, efforts to make weight teasing unacceptable are warranted.
Walking Associated With Public Transit: Moving Toward Increased Physical Activity in the United States
Authors: Freeland Amy L. , Banerjee Shailendra N. , Dannenberg Andrew L. , Wendel Arthur M.
Published: January 2013

Objectives. We assessed changes in transit-associated walking in the United States from 2001 to 2009 and documented their importance to public health.

Methods. We examined transit walk times using the National Household Travel Survey, a telephone survey administered by the US Department of Transportation to examine travel behavior in the United States.

Results. People are more likely to transit walk if they are from lower income households, are non-White, and live in large urban areas with access to rail systems. Transit walkers in large urban areas with a rail system were 72% more likely to transit walk 30 minutes or more per day than were those without a rail system. From 2001 to 2009, the estimated number of transit walkers rose from 7.5 million to 9.6 million (a 28% increase); those whose transit-associated walking time was 30 minutes or more increased from approximately 2.6 million to 3.4 million (a 31% increase).

Conclusions. Transit walking contributes to meeting physical activity recommendations. Study results may contribute to transportation-related health impact assessment studies evaluating the impact of proposed transit systems on physical activity, potentially influencing transportation planning decisions.
Population Use, Sales, and Design: A Multidimensional Assessment of “Light” Cigarettes in the United States, 2009
Authors: Behm Ilan , Sokol Natasha A. , Kennedy Ryan David , Rees Vaughan W. , Connolly Gregory N.
Published: January 2013

Objectives. We compared multiple measures of surveillance of “light” cigarette use, including population use, sales, and design features. Measures were obtained before the 2010 descriptors ban to establish a baseline for future evaluation of the effect of the ban.

Methods. We examined light cigarette use, sales, and design using 3 data sets from 2009. We assessed population use using National Survey on Drug Use and Health data. Sales data were drawn from AC Nielsen. We gathered design features, including nicotine concentration, filter ventilation, and weight, from tobacco industry disclosures mandated by the Massachusetts Department of Public Health.

Results. In 2009, 52.7% of smokers self-reported light cigarette use, which accounted for 56.0% of cigarettes sold in the United States. Self-reported light smokers were more likely to be female, White, older, and nondaily smokers. Of design features analyzed, only average filter ventilation differed significantly between light and “full-flavored” cigarettes.

Conclusions. Assessment of the impact of the descriptors ban and any future policies surrounding light cigarettes should use multiple surveillance strategies, including measures of population use, sales, and cigarette design.
There’s No Place Like Home: First-Year Use of the “I Know” Home Testing Program for Chlamydia and Gonorrhea
Authors: Rotblatt Harlan , Montoya Jorge A. , Plant Aaron , Guerry Sarah , Kerndt Peter R.
Published: January 2013

In response to high chlamydia and gonorrhea morbidity, particularly among young African American and Latina women, the Los Angeles County Department of Public Health launched a free home testing program for Chlamydia trachomatis and Neisseria gonorrhoeae. The primary objectives were to increase chlamydia and gonorrhea testing by removing key barriers and to motivate young women to screen routinely for these sexually transmitted diseases (STDs). The program was promoted with a social marketing campaign urging women to order home collection kits online or by telephone. In the program’s first year, 2927 kits were ordered and 1543 testable specimens returned; 131 women (8.5%) had a positive test result. The strong response, high morbidity, and program scalability indicated strong potential as a new tool for STD control.
The Dose–Response of Time Served in Prison on Mortality: New York State, 1989–2003
Authors: Patterson Evelyn J.
Published: January 2013

Objectives. I investigated the differential impact of the dose–response of length of stay on postprison mortality among parolees.

Methods. Using 1989–2003 New York State parole administrative data from the Bureau of Justice Statistics on state correctional facilities, I employed multinomial logistic regression analyses and formal demographic techniques that used the life table of the populations to deduce changes in life expectancy.

Results. Each additional year in prison produced a 15.6% increase in the odds of death for parolees, which translated to a 2-year decline in life expectancy for each year served in prison. The risk was highest upon release from prison and declined over time. The time to recovery, or the lowest risk level, was approximately two thirds of the time served in prison.

Conclusions. Incarceration reduces life span. Future research should investigate the pathways to this higher mortality and the possibilities of recovery.
Unintended Consequences: Abortion Training in the Years After Roe v Wade
Authors: Aksel Sarp , Fein Lydia , Ketterer Em , Young Emily , Backus Lois
Published: January 2013

The US Supreme Court’s 1973 Roe v Wade decision had clear implications for American women’s reproductive rights and physician ability to carry out patient choices. Its effect on physician abortion training was less apparent.

In an effort to increase patient access to abortions after Roe, provision shifted from hospitals to nonhospital clinics. However, these procedures and patients were taken out of the medical education realm, and physicians became vulnerable to intimidation. The consequent provider shortage created an unexpected barrier to abortion access.

Medical Students for Choice was founded in 1993 to increase abortion-training opportunities for medical students and residents. Its mission ensures that motivated medical students will learn and a growing number of physicians will commit to comprehensive abortion provision.
Job Strain and Ambulatory Blood Pressure: A Meta-Analysis and Systematic Review
Authors: Landsbergis Paul A. , Dobson Marnie , Koutsouras George , Schnall Peter
Published: January 2013

We reviewed evidence of the relationship between job strain and ambulatory blood pressure (ABP) in 29 studies (1985–2012). We conducted a quantitative meta-analysis on 22 cross-sectional studies of a single exposure to job strain. We systematically reviewed 1 case–control study, 3 studies of cumulative exposure to job strain, and 3 longitudinal studies.

Single exposure to job strain in cross-sectional studies was associated with higher work systolic and diastolic ABP. Associations were stronger in men than women and in studies of broad-based populations than those with limited occupational variance. Biases toward the null were common, suggesting that our summary results underestimated the true association.

Job strain is a risk factor for blood pressure elevation. Workplace surveillance programs are needed to assess the prevalence of job strain and high ABP and to facilitate workplace cardiovascular risk reduction interventions.
Abortion in Sri Lanka: The Double Standard
Authors: Kumar Ramya
Published: January 2013

In Sri Lanka, women do not have access to legal abortion except under life-saving circumstances. Clandestine abortion services are, however, available and quite accessible.

Although safe specialist services are available to women who can afford them, others access services under unsafe and exploitative conditions. At the time of this writing, a draft bill that will legalize abortion in instances of rape, incest, and fetal abnormalities awaits approval, amid opposition.

In this article, I explore the current push for legal reform as a solution to unsafe abortion. Although a welcome effort, this amendment alone will be insufficient to address the public health consequences of unsafe abortion in Sri Lanka because most women seek abortions for other reasons. Much broader legal and policy reform will be required.
Abortion in a Progressive Legal Environment: The Need for Vigilance in Protecting and Promoting Access to Safe Abortion Services in South Africa
Authors: Trueman Karen A. , Magwentshu Makgoale
Published: January 2013

The importance of South Africa as a model for reproductive self-determination in Africa cannot be underestimated. Abortion has been legal since 1996, and the country has some of the most developed government systems for the provision of abortion care on the continent.

Yet in the same way opponents of abortion in the United States have whittled away at access with increased bureaucracy, South Africa faces similar assaults that leave women without safe care and threaten to turn back achievements made during the past 16 years.

I explore the history of the law, subsequent legal challenges, and new threats to women’s access to abortion services, including service delivery issues that may influence the future of public health in the country.
CO2-Soluble, Nonionic, Water-Soluble Surfactants That Stabilize CO2-in-Brine Foams
Authors: Xing D. , Wei B. , McLendon W. , Enick R. , McNulty S. , Trickett K. , Mohamed A. , Cummings S. , Eastoe J. , Rogers S. , Crandall D. , Tennant B. , McLendon T. , Romanov V. , Soong Y.
Published: January 2013

Several commercially available and a few experimental, nonionic surfactants were identified that are capable of dissolving in carbon dioxide (CO2) in dilute concentration at typical minimum- miscibility-pressure (MMP) conditions and, upon mixing with brine in a high-pressure windowed cell, stabilizing CO2-in-brine foams. These slightly CO2-soluble, water-soluble surfactants include branched alkylphenol ethoxylates, branched alkyl ethoxylates, a fatty-acid-based surfactant, and a predominantly linear ethoxylated alcohol. Many of the surfactants were between 0.02 to 0.06 wt% soluble in CO2 at 1,500 psia and 25°C, and most demonstrated some capacity to stabilize foam. The most- stable foams observed in a high-pressure windowed cell were attained with branched alkylphenol ethoxylates, several of which were studied in high-pressure small-angle-neutron-scattering (HP SANS) tests, transient mobility tests using Berea sandstone cores, and high-pressure computed-tomography (CT)-imaging tests using polystyrene cores. HP SANS analysis of foams residing in a small windowed cell demonstrated that the nonylphenol ethoxylate SURFONIC® N-150 [15 ethylene oxide (EO) groups] generated emulsions with a greater concentration of droplets and a broader distribution of droplet sizes than the shorter-chain analogs with 9–12 ethoxylates. The in-situ formation of weak foams was verified during transient mobility tests by measuring the pressure drop across a Berea sandstone core as a CO2/surfactant solution was injected into a Berea sandstone core initially saturated with brine; the pressure-drop values when surfactant was dissolved in the CO2 were at least twice those attained when pure CO2 was injected into the same brine-saturated core. The greatest mobility reduction was achieved when surfactant was added both to the brine initially in the core and to the injected CO2. CT imaging of CO2 invading a polystyrene core initially saturated with 5 wt% KI brine indicated that despite the oil-wet nature of this medium, a sharp foam front propagated through the core, and CO2 fingers that formed in the absence of a surfactant were completely suppressed by foams formed because of the addition of nonylphenol ethoxylate surfactant to the CO2 or the brine.
Casing Burst Stresses in Particulate-Filled Annuli: Where Is the Cement?
Authors: Kalil Issa A. , McSpadden Albert R.
Published: January 2013

For burst design, engineers routinely assume that the casing annular space is filled by a fluid equivalent. This assumption ignores mechanical resistance provided by solid cement. Some studies addressed this shortcoming by modeling the cement sheath as a solid with elastic failure criteria. Prior work used cement elastic modulus and Poisson's ratio to classify cement as "ductile" (soft) or "brittle" (hard).

In the current study, numerical results from finite-element analysis (FEA) indicate that casing burst resistance is increased by the presence of the cement sheath. This study focuses solely on improvement offered by the cement sheath to casing burst resistance and ignores consequences of cement failure on overall well integrity.

Comparisons are provided for casing burst resistance, assuming various backup profiles. These include fluid hydrostatics, solid cement matrix (both elastic and plastic response), and cement as "loose" particles. The fluid hydrostatics include mud weight in hole, cement-slurry density, mixed-water density; normal pressure (saltwater column), and actual pore pressure. Calculations show that these fluid profiles are conservative when used as burst-resistance backup. Original cement-slurry density is least conservative.

Because well designers are familiar with fluid profile backup assumptions in casing burst design, recommendations are provided to approximate cement behavior as particles with a fluid profile. This allows ease of calculation and is consistent with current practice. Guidelines are provided to explicitly calculate the enhanced casing burst resistance caused by the particulate cement.
Comparison of Skin Factors for Perforated Completions Calculated With Computational-Fluid-Dynamics Software and the Karakas-Tariq Semianalytical Model
Authors: Sun Datong , Li Baoyan , Gladkikh Mikhail , Satti Rajani , Evans Randy
Published: January 2013

Many factors affect flow performance of perforated completions, including perforation-tunnel geometry, drilling and perforation damage, and formation-permeability anisotropy. The combined effect of these factors is usually accounted for by means of a single parameter: total-skin factor, which is an important input parameter for inflow-performance-relationship prediction and reservoir simulation. The Karakas and Tariq (1991) semianalytical skin-factor model is the most commonly used in the industry (Bell et al. 1995; Kabir and Salmachi 2009; Zhan et al. 2012). It assumes that the total-skin factor can be expressed as a linear combination of horizontal skin, vertical skin considering permeability anisotropy, perforation-damaged-zone skin, and other skins. The purpose of this study is to investigate the validity of the Karakas-Tariq semianalytical model in a realistic operational range of perforating-parameter values.

For this purpose, we use computational-fluid-dynamics (CFD) software to simulate the production flow of a vertical cased-and-perforated well in a representative 3D geometric formation. We consider three effects: drilling damage, perforation damage (crushed zone around the perforation tunnel), and permeability anisotropy, assuming no pressure drop along the interior of perforation tunnels. All combinations of the three effects are considered. Computed skins are compared with the semianalytical skin model of Karakas and Tariq (1991).

Computed results show good comparisons between skin factors calculated by use of CFD software and the Karakas and Tariq model (1991) for most cases. However, significant deviations in skin-factor comparisons are observed when both perforation damage and formation anisotropy exist if considering permeability anisotropy in the crushed zone. We also conclude that an additional skin-factor term, related to the ratio of the modified wellbore radius to the original wellbore radius, should be explicitly listed in the Karakas and Tariq model (1991) for perforation tunnels extending beyond the drilling-damage zone.

Calculated CFD skin factors can be used as a database for predictive prejob analysis. Deviation between skin factors calculated by use of CFD and the Karakas and Tariq (1991) model highlights the need for improving industry methods to estimate skin factor in vertical perforated completions if considering crushed-zone anisotropy.
Experiments and Analysis of Multiscale Viscous Fingering During Forced Imbibition
Authors: Sharma Jyotsna , Inwood S.B.. B. , Kovscek A.R.. R.
Published: January 2013

Immiscible displacement of one fluid by another in porous media has practical applications when viscous oil is produced by water injection. A greater understanding of the flow patterns that evolve during such unstable displacements yields insights into improving predictive capability and increasing oil recovery. Immiscible multiphase displacement exhibits a wide range of behaviors depending on the relative magnitude of viscous, capillary, and gravity forces. Using flow-visualization images from forced-imbibition experiments carried out in etched-silicon micromodels, we show that the conventional Darcy-type modeling of fluid flux is not predictive under unstable, immiscible, forced-imbibition conditions at the scale of interest. When a less viscous fluid displaces a more viscous fluid at low capillary numbers, the displacement patterns show viscous instabilities in the form of fingers and local capillary control of interface movement. We show that such complex displacement patterns are well modeled using statistical theories. We derive a scaling model to describe quantitatively the functional forms for saturation, fractional flow, and capillary dispersion profiles using the self-similar characteristics inherent in the displacement patterns. For the specific range of flow rates (Nc ~ 10−7) and oil/water viscosity ratios (M ~ 8–400) considered in our experiments, both capillary and viscous forces are important, and the displacement pattern indicates fractal features. Results show that functional relations of the scaling model are in considerable agreement with our experimental data.
North Sea World Record Installation–Deepest Sealed Multilateral System
Authors: Eck-Olsen Johan , Solheim Ove Andre , Morten Falnes
Published: January 2013

In October 2010, the deepest-set sealed multilateral (ML) junction in the industry was installed at 6900-m measured depth (MD) in Oseberg South Well 30/9-F-9 AY1/Y2. The differential pressure across the junction in the well was expected to be in the range of 250 bar. To meet this pressure requirement, a junction system rated to 370 bar was identified. The high-pressure junction components and entire multilateral system have undergone an extensive testing and qualification program, including several component tests and a full-scale system interface and integration test.

A 10¾-in. precut window was installed as an integral part of the 10¾-in. liner. The plan was to perform the milling operation through this window. A stuck-string incident during the 10¾-in. liner installation accidentally caused the liner to drop in the hole. The liner ended up at the wrong orientation, and the window could consequently not be used.

The main bore was drilled to total depth (TD) at 8583-m MD, and the 7-in. liner was run and cemented. After the liner perforation, the BL operations started with the installation of an anchor packer and a latch interface assembly (LIA). The milling operation was performed in a two-step operation with milling of a first-pass window by use of a downhole milling machine before installing a whipstock and performing the second-pass milling operation.

The lateral branch was drilled to TD at 8258-m MD, and a 5½-in. screen completion was run and dropped off into the 8½-in. open hole. The junction was finally stung into a completion deflector, simultaneously with an openhole seal stinger entering the top of the screen liner in the open hole, tying the branches together. A 6900-m upper completion string with inflow control valves was finally installed to allow for surface control of the two branches.

Despite severe drilling problems in the transport sections of the well, the ML operations were deemed successful. Major risk and challenges with this well design involved orientation of the 10¾-in. liner (to position the premilled window) at this depth, debris management after milling operations, and general depth control during junction construction. Debris management in particular became essential as the backup ML solution meant milling steel rather than aluminum.

Although the two different reservoirs could be drained by two conventional extended-reach-drilling (ERD) wells, this would be a less cost-efficient solution. Furthermore, the construction of an ML well means that the aforementioned challenges drilling the transport sections had to be handled only once. The successful installation at this depth has proved that ML technology is feasible for use in ERD wells, either to improve the total reservoir exposure or to reach multiple targets from one well.
Qualitative and Quantitative Analyses of the Three-Phase Distribution of Oil, Water, and Gas in Bentheimer Sandstone by Use of Micro-CT Imaging
Authors: Feali M.. , Pinczewski W.V.. V. , Cinar Y.. , Arns C.H.. H. , Arns J.-Y.. -Y. , Turner M.. , Senden T.. , Francois N.. , Knackstedt M..
Published: January 2013

It is now widely acknowledged that continuous oil-spreading films observed in 2D glass-micromodel studies for strongly water-wet three-phase oil, water, and gas systems are also present in real porous media, and they result in lower tertiary-gasflood residual oil saturations than for corresponding negative spreading systems that do not display oil-spreading behavior. However, it has not yet been possible to directly confirm the presence of continuous spreading films in real porous media in three dimensions, and little is understood of the distribution of the phases within the complex geometry and topology of actual porous media for different spreading conditions. This paper describes a study with high-resolution X-ray microtomography to image the distribution of oil, water, and gas after tertiary gasflooding to recover waterflood residual oil for two sets of fluids, one positive spreading and the other negative spreading, in strongly water-wet Bentheimer sandstone.

We show that, for the positive spreading system, oil-spreading films maintain the connectivity of the oil phase down to low oil saturation. At similar oil saturation, no oil films are observed for the negative spreading system, and the oil phase is disconnected. The spatial continuity of the oil-spreading films over the imaged volume is confirmed by the computed Euler characteristic for the oil phase.
Automatic Isotherm Derivation From Field Data for Oilfield Scale-Inhibitor Squeeze Treatments
Authors: Vazquez Oscar , Corne David , Mackay Eric James , Jordan Myles Martin
Published: January 2013

Oilfield scale formation represents a significant flow-assurance challenge to the oil and gas industry, because of increasing water production worldwide and higher oil prices. Scale-inhibitor (SI) squeeze treatment is the most widespread method to combat downhole scaling. To predict SI squeeze treatments accurately for further optimization, it is necessary to simulate the SI retention in the formation, which may be described by a pseudoadsorption isotherm. Although these are often derived from coreflood experiments, sometimes they are not appropriate for modeling well treatments because the core tests on which they are based cannot fully represent field-scale processes. In practice, the parameters of an analytic form of the isotherm equation are modified by trial and error by an experienced practitioner until a match is obtained between the prediction and the return profile of the first treatment in the field.

The main purpose of this paper is to present a stochastic hill-climbing algorithm for automatic isotherm derivation. The performance of the algorithm was evaluated by use of data from three field cases. Two success criteria were defined: the ability to match a single historical treatment and the ability to predict subsequent successive treatments. To test for the second criterion, a candidate isotherm was derived from the first treatment in a well that was treated with the same chemical package on consecutive occasions, and then the predictions by use of the suggested solution were compared with the observed SI concentration-return profiles from the subsequent treatments. In all the calculations, the performances of both the isotherms suggested by the hill-climbing algorithm and the isotherms derived by trial and error were compared. The results demonstrate that the hill-climbing algorithm is an effective technique for deriving an isotherm for a single treatment, although predictions for successive treatments worsened slightly with each treatment.
Explicitly Coupled Thermal Flow Mechanical Formulation for Gas-Hydrate Sediments
Authors: Klar Assaf , Uchida Shun , Soga Kenichi , Yamamoto Koji
Published: January 2013

This paper presents an explicit time-marching formulation for the solution of the coupled thermal flow mechanical behavior of gas-hydrate sediment. The formulation considers the soil skeleton as a deformable elastoplastic continuum, with an emphasis on the effect of hydrate (and its dissociation) on the stress-strain behavior of the soil. In the formulation, the hydrate is assumed to deform with the soil and may dissociate into gas and water. The formulation is explicitly coupled, such that the changes in temperature because of energy flow and hydrate dissociation affect the skeleton stresses and fluid (water and gas) pressures. This, in return, affects the mechanical behavior. A simulation of a vertical well within a layered soil is presented. It is shown that the heterogeneity of hydrate saturation causes different rates of dissociation in the layers. The difference alters the overall gas production and also the mechanical-deformation pattern, which leads to loading/unloading shearing along the interfaces between the layers.