bluuebunny/crossref_metadata_2025 huggingface dataset:
Efficacy of a Woman-Focused Intervention to Reduce HIV Risk and Increase Self-Sufficiency Among African American Crack Abusers
Authors: Wechsberg Wendee M. , Lam Wendy K. K. , Zule William A. , Bobashev Georgiy
Published: December 2008

Objectives. This study compares 3- and 6-month outcomes of a woman-focused HIV intervention for crack abusers, a revised National Institute on Drug Abuse standard intervention, and a control group.

Methods. Out-of-drug-treatment African American women (n = 620) who use crack participated in a randomized field experiment. Risk behavior, employment, and housing status were assessed with linear and logistic regression.

Results. All groups significantly reduced crack use and high-risk sex at each follow-up, but only woman-focused intervention participants consistently improved employment and housing status. Compared with control subjects at 6 months, woman-focused intervention participants were least likely to engage in unprotected sex; revised standard intervention women reported greatest reductions in crack use.

Conclusions. A woman-focused intervention can successfully reduce risk and facilitate employment and housing and may effectively reduce the frequency of unprotected sex in the longer term.
Modeling the Effects of Different Infant Feeding Strategies on Infant Survival and Mother-to-Child Transmission of HIV
Authors: Ross Jay S. , Labbok Miriam H.
Published: December 2008

Objectives. We investigated how, under various conditions, the risk of mother-to-child transmission of HIV through breastfeeding compares with the risk of death from artificial feeding.

Methods. We developed a spreadsheet simulation model to predict HIV-free survival during 7 age intervals from 0 to 24 months for 5 different infant feeding scenarios in resource-poor settings.

Results. Compared with artificial feeding, breastfeeding during the first 6 months by HIV-positive mothers increases HIV-free survival by 32 per 1000 live births. After 6 months, as the age-specific mortality rate and risk of death caused by replacement feeding both decline, replacement feeding appears to be safer.

Conclusions. Under conditions common in countries with high HIV prevalence, replacement feeding by HIV-infected mothers should not be generally encouraged until after the infant is approximately 6 months old.
Prevalence and Incidence of HIV, Hepatitis B Virus, and Hepatitis C Virus Infections Among Males in Rhode Island Prisons
Authors: Macalino Grace E. , Vlahov David , Sanford-Colby Stephanie , Patel Sarju , Sabin Keith , Salas Christopher , Rich Josiah D.
Published: December 2008

Objectives. We evaluated prevalence and intraprison incidence of HIV, hepatitis B virus, and hepatitis C virus infections among male prison inmates.

Methods. We observed intake prevalence for 4269 sentenced inmates at the Rhode Island Adult Correctional Institute between 1998 and 2000 and incidence among 446 continuously incarcerated inmates (incarcerated for 12 months or more).

Results. HIV, hepatitis B virus, and hepatitis C virus prevalences were 1.8%, 20.2%, and 23.1%, respectively. Infections were significantly associated with injection drug use (odds ratio = 10.1, 7.9, and 32.4). Incidence per 100 person-years was 0 for HIV, 2.7 for HBV, and 0.4 for HCV.

Conclusions. High infection prevalence among inmates represents a significant community health issue. General disease prevention efforts must include prevention within correctional facilities. The high observed intraprison incidence of HBV underscores the need to vaccinate prison populations.
Evaluating the Effectiveness of Public Health Leadership Training: The NEPHLI Experience
Authors: Saleh Shadi S. , Williams Dwight , Balougan Modinat
Published: December 2008

Objectives. We assessed the effect of public health leadership training on the capacity of public health leaders to perform competencies derived from the list of “Ten Essential Public Health Services” presented in 1994 by the steering committee of the Public Health Functions Project.

Methods. Graduating scholars of the Northeast Public Health Leadership Institute were surveyed to determine differences in skill level in 15 competency areas before and after training. Surveys were completed after program completion.

Results. The training program improved the skill levels of participants in all 15 competency areas. A relation also was detected between the frequency of use of the competency and the improvement experienced.

Conclusions. Public health leadership training programs are effective in improving the skills of public health workers.
WIC Participation, Breastfeeding Practices, and Well-Child Care Among Unmarried, Low-Income Mothers
Authors: Chatterji Pinka , Brooks-Gunn Jeanne
Published: December 2008

We estimated the effect of Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) participation in 1999 to 2000 on breastfeeding initiation and duration and well-child care. We applied multivariate regression to a sample of 2136 unmarried, low-income, urban mothers from the Fragile Families and Child Wellbeing Study. WIC participation was associated with small increases in the probabilities of initiating breastfeeding and having had at least 4 well-child visits since birth—behaviors that benefit infants beyond the newborn period—but not with breastfeeding duration.
The Benefit of Health Insurance Coverage of Contraceptives in a Population-Based Sample
Authors: Kurth Ann , Weaver Marcia , Lockhart David , Bielinski Lori
Published: December 2008

This study estimated the value of contraceptives, through a random-digit-dialed survey of willingness to pay for health insurance coverage of contraceptives among 659 Washington State adults. People valued contraceptives at 5 times the actuarial cost; in general, women and reproductive-aged persons were willing to pay more, but low-income men highly valued contraceptives. Most respondents (85%) said that contraceptives should be covered by health insurance plans. The full benefit of contraceptives exceeds their cost.
Young Males' Sexual Education and Health Services
Authors: Howard Marion , Davis Jackie , Evans-Ray Donnie , Mitchell Marie , Apomah Marian
Published: December 2008

This study examined the basis for one hospital’s decision to restructure its teen family planning clinical services. We examined results of surveys conducted from 1998 to 2003 with more than 2000 mostly African American eighth-grade boys. Most young males wanted to postpone sexual intercourse, but an even greater percentage were willing to use a method of protection. The hospital determined that it needed to give the same in-hospital clinical and counseling support to young males as it gives to young females.
Physician Assistants as Providers of Surgically Induced Abortion Services
Authors: Goldman Marlene B. , Occhiuto Jane S. , Peterson Laura E. , Zapka Jane G. , Palmer R. Heather
Published: December 2008

Objectives. We compared complication rates after surgical abortions performed by physician assistants with rates after abortions performed by physicians.

Methods. A 2-year prospective cohort study of women undergoing surgically induced abortion was conducted. Ninety-one percent of eligible women (1363) were enrolled.

Results. Total complication rates were 22.0 per 1000 procedures (95% confidence interval [CI] = 11.9, 39.2) performed by physician assistants and 23.3 per 1000 procedures (95% CI = 14.5, 36.8) performed by physicians (P = .88). The most common complication that occurred during physician assistant–performed procedures was incomplete abortion; during physician-performed procedures the most common complication was infection not requiring hospitalization. A history of pelvic inflammatory disease was associated with an increased risk of total complications (odds ratio = 2.1; 95% CI = 1.1, 4.1).

Conclusions. Surgical abortion services provided by experienced physician assistants were comparable in safety and efficacy to those provided by physicians.
Racial/Ethnic Differences in the Prevalence of Depressive Symptoms Among Middle-Aged Women: The Study of Women’s Health Across the Nation (SWAN)
Authors: Bromberger Joyce T. , Harlow Sioban , Avis Nancy , Kravitz Howard M. , Cordal Adriana
Published: December 2008

Objectives. We examined racial/ethnic differences in significant depressive symptoms among middle-aged women before and after adjustment for socioeconomic, health-related, and psychosocial characteristics.

Methods. Racial/ethnic differences in unadjusted and adjusted prevalence of significant depressive symptoms (score ≥ 16 on the Center for Epidemiologic Studies Depression [CES-D] Scale) were assessed with univariate and multiple logistic regressions.

Results. Twenty-four percent of the sample had a CES-D score of 16 or higher. Unadjusted prevalence varied by race/ethnicity (P < .0001). After adjustment for covariates, racial/ethnic differences overall were no longer significant.

Conclusions. Hispanic and African American women had the highest odds, and Chinese and Japanese women had the lowest odds, for a CES-D score of 16 or higher. This variation is in part because of health-related and psychosocial factors that are linked to socioeconomic status.
Association Between Childhood Socioeconomic Status and Coronary Heart Disease Risk Among Postmenopausal Women: Findings From the British Women's Heart and Health Study
Authors: Lawlor Debbie A. , Smith George Davey , Ebrahim Shah
Published: December 2008

Objectives. We assessed the association between childhood socioeconomic status (SES) and coronary heart disease among postmenopausal women.

Methods. We conducted a cross-sectional analysis of 3444 women aged 60 to 79 years.

Results. There was an independent linear association between childhood and adult SES and coronary heart disease. The association between childhood SES and coronary heart disease was attenuated when we adjusted for insulin resistance syndrome, adult smoking, physical activity, biomarkers of childhood nutrition, and passive smoking.

Conclusions. The association between adverse childhood SES and coronary heart disease is in part mediated through insulin resistance, which may be influenced by poor childhood nutrition, and in part through the association between childhood SES and adult behavioral risk factors.
Weapons in the Lives of Battered Women
Authors: Sorenson Susan B. , Wiebe Douglas J.
Published: December 2008

Objectives. We assessed weapon use in intimate partner violence and perspectives on hypothetical firearm policies.

Methods. We conducted structured in-person interviews with 417 women in 67 battered women’s shelters.

Results. Words, hands/fists, and feet were the most common weapons used against and by battered women. About one third of the battered women had a firearm in the home. In two thirds of these households, the intimate partner used the gun(s) against the woman, usually threatening to shoot/kill her (71.4%) or to shoot at her (5.1%). Most battered women thought spousal notification/consultation regarding gun purchase would be useful and that a personalized firearm (“smart gun”) in the home would make things worse.

Conclusions. A wide range of objects are used as weapons against intimate partners. Firearms, especially handguns, are more common in the homes of battered women than in households in the general population.
The Potential Protective Effect of Youth Assets on Adolescent Alcohol and Drug Use
Authors: Oman Roy F. , Vesely Sara , Aspy Cheryl B. , McLeroy Kenneth R. , Rodine Sharon , Marshall LaDonna
Published: December 2008

Objectives. We examined the association between adolescent alcohol and drug use and 9 youth assets in a low-income, inner-city population.

Methods. An in-person survey of 1350 adolescents and parents assessed youth assets and risk behaviors. We analyzed data with χ2 tests and logistic regression analyses.

Results. When we controlled for appropriate variables, there were significant positive relationships between several youth assets and nonuse of alcohol and drugs. Furthermore, youths who possessed all of the statistically significant youth assets were 4.44 times more likely to report nonuse of alcohol and 5.41 times more likely to report nonuse of drugs compared with youths who possessed fewer youth assets.

Conclusions. Our study supports the view that specific youth assets may protect youths from alcohol and drug use.
Health Care System Changes and Reported Musculoskeletal Disorders Among Registered Nurses
Authors: Lipscomb Jane , Trinkoff Alison , Brady Barbara , Geiger-Brown Jeanne
Published: December 2008

Objectives. We evaluated the impact of health care system changes on nurses’ health, and we studied reported musculoskeletal disorders associated with these changes.

Methods. This cross-sectional study (n = 1163) defined a musculoskeletal disorder case as moderate pain that lasted at least 1 week or occurred monthly during the past year. Nurses were asked about changes in the health care system in the past year, and responses to 12 changes were summed and were categorized as low, moderate, or high changes.

Results. When the changes were summed, the adjusted odds ratios for musculoskeletal disorders for more than 6 versus 0 to 1 changes were (1) neck: 4.45 (95% confidence interval [CI] = 1.97, 10.08), (2) shoulder: 2.63 (95% CI = 1.17, 5.91), and (3) back: 3.42 (95% CI = 1.61, 7.27).

Conclusions. The adverse impact on health caused by the changing health care system must be addressed to prevent further injuries among nurses.
Function and Response of Nursing Facilities During Community Disaster
Authors: Saliba Debra , Buchanan Joan , Kington Raynard S.
Published: December 2008

Objectives. We sought to describe the role and function of nursing facilities after disaster.

Methods. We surveyed administrators at 144 widely dispersed nursing facilities after the Los Angeles Northridge earthquake.

Results. Of the 113 (78%) nursing facilities that responded (11 365 beds), 23 sustained severe damage, 5 closed (625 beds), and 72 lost vital services. Of 87 nursing facilities implementing disaster plans, 56 cited problems that plans did not adequately address, including absent staff, communication problems, and insufficient water and generator fuel. Fifty-nine (52%) reported disaster-related admissions from hospitals, nursing facilities, and community residences. Nursing facilities received limited postdisaster assistance. Five months after the earthquake, only half of inadequate nursing facility disaster plans had been revised.

Conclusions. Despite considerable disaster-related stresses, nursing facilities met important community needs. To optimize disaster response, communitywide disaster plans should incorporate nursing facilities.
Graphic Canadian Cigarette Warning Labels and Adverse Outcomes: Evidence from Canadian Smokers
Authors: Hammond David , Fong Geoffrey T. , McDonald Paul W. , Brown K. Stephen , Cameron Roy
Published: December 2008

Objectives. We assessed the impact of graphic Canadian cigarette warning labels.

Methods. We used a longitudinal telephone survey of 616 adult smokers.

Results. Approximately one fifth of participants reported smoking less as a result of the labels; only 1% reported smoking more. Although participants reported negative emotional responses to the warnings including fear (44%) and disgust (58%), smokers who reported greater negative emotion were more likely to have quit, attempted to quit, or reduced their smoking 3 months later. Participants who attempted to avoid the warnings (30%) were no less likely to think about the warnings or engage in cessation behavior at follow-up.

Conclusions. Policymakers should not be reluctant to introduce vivid or graphic warnings for fear of adverse outcomes.
Childhood Obesity in New York City Elementary School Students
Authors: Thorpe Lorna E. , List Deborah G. , Marx Terry , May Linda , Helgerson Steven D. , Frieden Thomas R.
Published: December 2008

Objectives. We estimated overweight and obesity in New York City elementary school children.

Methods. A multistage cluster sample of New York City public elementary school children was selected. Nurses measured children’s height and weight and used a standard protocol to determine body mass index (BMI). Demographic information was obtained from official school rosters. Overweight and obese were defined as BMI-for-age at or above the 85th and 95th percentiles, respectively.

Results. Of 3069 sampled students, 2681 (87%) were measured. The prevalence of overweight was 43% (95% confidence interval [CI] = 39%, 47%), more than half of whom were obese. Overall prevalence of obesity was 24% (95% CI = 21%, 27%), with at least 20% obesity in each grade, including kindergarten. Hispanic children had significantly higher levels (31%; 95% CI = 29%, 34%) than Black (23%; 95% CI = 18%, 28%) or White children (16%; 95% CI = 12%, 20%). Asian children had the lowest level of obesity among all racial/ethnic groups (14.4%, 95% CI = 10.9, 18.7).

Conclusions. Obesity among public elementary school children in New York City is an important public health issue. Particularly high levels among Hispanic and Black children mirror national trends and are insufficiently understood.
Physical Education in Elementary School and Body Mass Index: Evidence from the Early Childhood Longitudinal Study
Authors: Datar Ashlesha , Sturm Roland
Published: December 2008

Objectives. We examined the effect of physical education instruction time on body mass index (BMI) change in elementary school.

Methods. We examined data from a national sample of 9751 kindergartners in the United States who were reported on for 2 years. We used a difference-in-differences approach to examine the effect of an increase in physical education instruction time between kindergarten and first grade on the difference in BMI change in the 2 grades, using the same child as the control.

Results. One additional hour of physical education in first grade compared with the time allowed for physical education in kindergarten reduces BMI among girls who were overweight or at risk for overweight in kindergarten (coefficient = −0.31, P < .001) but has no significant effect among overweight or at-risk-for-overweight boys (coefficient = −0.07, P = .25) or among boys (coefficient = 0.04, P = .31) or girls (coefficient = 0.01, P = .80) with a normal BMI.

Conclusions. Expanding physical education programs in schools, in the form in which they currently exist, may be an effective intervention for combating obesity in the early years, especially among girls.
Trends in Blood Lead Levels Among Children Enrolled in the Special Supplemental Nutrition Program for Women, Infants, and Children From 1996 to 2000
Authors: Zierold Kristina M. , Anderson Henry
Published: December 2008

We analyzed data from the Wisconsin Childhood Lead Poisoning Prevention Program to examine the distribution of and trends in elevated blood lead levels among WIC-enrolled children from 1996 until 2000. Higher blood lead levels were seen among WIC-enrolled children, and although not statistically significant, the rate of blood lead level decline among WIC-enrolled children was greater than among non-WIC-enrolled children.
Changes in Diet Quality of American Preschoolers Between 1977 and 1998
Authors: Kranz Sibylle , Siega-Riz Anna Maria , Herring Amy H.
Published: December 2008

Objectives. We determined diet quality trends among nationally representative samples of preschoolers between 1977 and 1998.

Methods. Adjusted diet quality index scores, overall intake, and tertiles of total score were compared for combined samples and 2 age groups using t tests with Bonferroni correction; surveys used were the US Department of Agriculture’s National Food Consumption Survey 1977–1979 (n = 2342), Continuing Survey of Food Intake by Individuals (CSFII) 1989–1991 (n = 858), and CSFII 1994–1996 and 1998 (n = 5355).

Results. Total scores increased slightly. Consumption of grains, fruits, and vegetables improved while added sugar and juice intake worsened.

Conclusions. Diet quality improved marginally since 1977. Consumption of fruits and vegetables needs to be increased and that of total and saturated fat, juice, and added sugar decreased.
The Relation of Breastfeeding and Body Mass Index to Asthma and Atopy in Children: A Prospective Cohort Study to Age 6 Years
Authors: Oddy Wendy H. , Sherriff Jill L. , de Klerk Nicholas H. , Kendall Garth E. , Sly Peter D. , Beilin Lawrence J. , Blake Kevin B. , Landau Louis I. , Stanley Fiona J.
Published: December 2008

Objectives. We investigated the relationship between breastfeeding, asthma and atopy, and child body mass index (BMI).

Methods. From a prospective birth cohort (n = 2860) in Perth, Western Australia, 2195 children were followed up to age 6 years. Asthma was defined as doctor-diagnosed asthma and wheeze in the last year, and atopy was determined by skin prick test of 1596 children. Breastfeeding, BMI, asthma, and atopy were regressed allowing for confounders and the propensity score for overweight.

Results. Using fractional polynomials, we found no association between breastfeeding and overweight. Less exclusive breastfeeding was associated with increased asthma and atopy, and BMI increased with asthma.

Conclusions. Less exclusive breastfeeding leads to increases in child asthma and atopy and a higher BMI is a risk factor for asthma.
Barriers to Buying Healthy Foods for People With Diabetes: Evidence of Environmental Disparities
Authors: Horowitz Carol R. , Colson Kathryn A. , Hebert Paul L. , Lancaster Kristie
Published: December 2008

Objectives. A community coalition compared the availability and cost of diabetes-healthy foods in a racial/ethnic minority neighborhood in East Harlem, with those in the adjacent, largely White and affluent Upper East Side in New York City.

Methods. We documented which of 173 East Harlem and 152 Upper East Side grocery stores stocked 5 recommended foods.

Results. Overall, 18% of East Harlem stores stocked recommended foods, compared with 58% of stores in the Upper East Side (P < .0001). Only 9% of East Harlem bodegas (neighborhood stores) carried all items (vs 48% of Upper East Side bodegas), though East Harlem had more bodegas. East Harlem residents were more likely than Upper East Side residents (50% vs 24%) to have stores on their block that did not stock recommended foods and less likely (26% vs 30%) to have stores on their block that stocked recommended foods.

Conclusions. A greater effort needs to be made to make available stores that carry diabetes-healthy foods.
Replacing Fats and Sweets With Vegetables and Fruits—A Question of Cost
Authors: Drewnowski Adam , Darmon Nicole , Briend André
Published: December 2008

Objectives. We examined the association between diet quality and estimated diet costs.

Methods. Freely chosen diets of 837 French adults were assessed by a dietary history method. Mean national food prices for 57 foods were used to estimate diet costs.

Results. Diets high in fat, sugar, and grains were associated with lower diet costs after adjustment for energy intakes, gender, and age. For most levels of energy intake, each additional 100 g of fats and sweets was associated with a €0.05–0.40 per day reduction in diet costs. In contrast, each additional 100 g of fruit and vegetables was associated with a €0.18–0.29 per day increase in diet costs.

Conclusions. Diets high in fats and sweets represent a low-cost option to the consumer, whereas the recommended “prudent” diets cost more.
Length of Hospital Stays Among Obese Individuals
Authors: Zizza Claire , Herring Amy H. , Stevens June , Popkin Barry M.
Published: December 2008

Objectives. We examined lengths of hospital stay among individuals categorized according to weight status.

Methods. We used data from the First National Health and Nutrition Examination Survey Epidemiologic Followup Survey to estimate length-of-stay differences.

Results. Individuals with body mass indexes (BMIs) of 35 kg/m2 or above, those with BMIs of 30 to 34 kg/m2, and those with BMIs of 25 to 29 kg/m2 had crude length-of-stay rates greater than those of normal-weight individuals. Association between BMI and length of stay varied over time.

Conclusions. Obese individuals experience longer hospital stays than normal-weight individuals.
Predictors of Help Seeking Among Connecticut Adults After September 11, 2001
Authors: Adams Mary L. , Ford Julian D. , Dailey Wayne F.
Published: December 2008

Objectives. We conducted a population-based telephone survey in an attempt to determine correlates of formal and informal help seeking after September 11, 2001.

Methods. Between October 15 and December 31, 2001, 1774 Connecticut Behavioral Risk Factor Surveillance System respondents were asked questions directly related to their experiences of September 11.

Results. Multivariate logistic regression analyses showed that receipt of formal help was predicted by sleep problems, close association with a victim, reports of increased smoking or drinking, and receipt of informal help. Age, gender, reports of 1 or more problems, and formal help seeking predicted receipt of informal help.

Conclusions. Public health planning and bioterrorism preparedness should include programs addressing increased smoking and drinking, sleep problems, and bereavement in the wake of disasters.
Usefulness of Tobacco Check Boxes on Death Certificates: Texas, 1987–1998
Authors: Zevallos Juan Carlos , Huang Philip , Smoot Monica , Condon Kenneth , Alo Celan
Published: December 2008

Objectives. We compared reports of deaths in which tobacco use was a contributing factor (“tobacco-associated deaths”) before and after the addition to death certificates in Texas of a check-box question asking whether tobacco use contributed to an individual’s death.

Methods. We examined Texas vital statistics files from 1987 to 1998. We calculated differences in percentages of reported tobacco-associated deaths (and 95% confidence intervals [CIs]) for the periods 1987 to 1992, before the addition of the check-box question, and 1993 to 1998, after the additon of the check-box.

Results. Reports of tobacco-associated deaths were significantly less frequent before addition of the check-box question (0.7%; 95% CI = 0.4%, 1.0%) than after addition of the question (13.9%; 95% CI = 13.0%, 14.7%). From 1993 to 1998, percentages of tobacco-associated deaths reported on the check-box question increased steadily.

Conclusions. The addition of a tobacco-associated-death check box on Texas death certificates significantly increased reporting of tobacco use contributions to mortality.
Antidiabetic Activity Assessment of Argania spinosa Oil
Authors: Bnouham Mohamed , Bellahcen Said , Benalla Wafaa , Legssyer Abdelkhaleq , Ziyyat Abderrahim , Mekhfi Hassane
Published: December 2008

Background: Argan or Argania spinosa (L.) Skeels, of the family sapotaceae which is an endemic species of the western south Morocco is used for its antidiabetic activity in local traditional medicine. All the parts of the plants are used to prepare remedies against various diseases. Recently, some studies suggest that Argan oil could play a beneficial role in cardiovascular diseases prevention.Aim: The goal of the present work is to show more evidences of the antidiabetic activity of Argan oil extracted from the almonds of Argan tree.Methods: In a first experiment, we tested the antihyperglycemiant effect on oral glucose tolerance test in healthy rats and streptozotocin-induced diabetic rats (60 mg/kg). In the second subchronic study, we tested the effect of the repeated oral administration of Argan oil (2 ml/kg during 15 days) on streptozotocin-induced diabetic rats. Moreover, the effect of Argan oil on the intestinal glucose absorption was tested in a jejunum segment by the technique of the in situ perfusion.Results: In the OGTT experiment of healthy rats and diabetic rats, the intraperitoneal administration of Argan oil (2.5 ml/kg) 30 minutes before the oral glucose loading (1g/kg) induced a significant reduction of glycemia, at 60 minutes and the decrease was persistent until the end of experiments (180 min) when compared to controls. In the subchronic treatment, the results showed a significant improvement of body mass and a significant reduction of the glycemia (55 %, p<0.001) at the end of experiment, when compared with untreated diabetic rats. Moreover, Argan oil reduced significantly (19.3 %, p<0.05) the amount of absorbed glucose in perfused jejunum segment versus controls. This effect was less than that of acarbose (alpha-glucosidase inhibitor).Conclusion: The consumption of Argan oil as a traditional food has the potential to reduce hyperglycemia-induced pathogenesis. It also explains the basis for its traditional use by rural community of western south Morocco.
Uncertainty Analysis of Primary Resource Savings at Cogeneration
Authors: Veidenbergs I. , Blumberga D. , Romagnoli F. , Vīgants E. , Rošā M.
Published: December 2008

Uncertainty Analysis of Primary Resource Savings at Cogeneration

The article provides the uncertainty analysis for electricity and heat energy production measurements at a cogeneration plant. It is analysed how the uncertainty in the input data affects the uncertainty in the data on primary resource savings. In the work, the standard uncertainties have been estimated for both data sets. The uncertainty budget is defined for determination of the primary energy resource savings.
KPIM of Gas Transportation: Robust Modification of Gas Pipeline Equations
Authors: Falade A. , Olaberinjo A. , Oyewola M. , Babalola F. , Adaramola S.
Published: December 2008

KPIM of Gas Transportation: Robust Modification of Gas Pipeline Equations

Studies of the flow conditions of natural gases in pipelines have led to the development of complex equations for relating the volume transmitted through a gas pipeline to the various factors involved, thus deciding the optimum pressures and pipeline dimensions to be used. From equations of this type, various combinations of pipe diameter and wall thickness for a desired rate of gas throughput can be calculated. This research work presents modified forms of the basic gas flow equation for horizontal flow developed by Weymouth and the basic gas flow equation for inclined flow developed by Ferguson. The modified equations incorporate non-iterative forms of the Colebrook-White friction factor into the original forms of the Weymouth's and Ferguson's equations. These modified equations thus eliminate the need for iteration in predicting the flow rate of gas through pipelines as is the case with their original forms when the Colebrook-White friction factor is used. The modified equations also have a wider range of application since the Colebrook-White friction factor is valid for turbulent gas flow as well as for gas flow in a transition zone. On comparing the results it can be seen that the modified Ferguson's equation gives a more accurate prediction of gas flow rates because it takes the pipeline elevation into account. Lower deviations from measured gas flow rates were observed with the modified Ferguson's equation than with the modified basic gas flow equation. The deviations observed using the modified Ferguson equation were found to range from -0.16% to +3.21%. Conclusively, these less cumbersome newly developed equations with high degree reliability will be useful in predicting the rates of gas flow for a wide range of its conditions, pipeline elevation and pipeline lengths.
The Effect of Strategic Alliances Between Key Competitors on Firm Performance
Authors: Ritala Paavo , Hallikas Jukka , Sissonen Heli
Published: December 2008

Cooperation between competing firms (or coopetition) has been under increasing research interest during the last decade. It is generally proposed that coopetition can be a beneficial strategy that can enable gaining a competitive advantage. Current contributions linking coopetition with actual firm performance, however, are few. In order to address this issue, we conduct an empirical study in the global information and communication technology sector to examine the effect of strategic alliances between key competitors on the performance of a single firm. Our results indicate that a high relative number of strategic alliances among a group of firm’s key competitors contributes negatively to firm performance. This implies that firms should be aware of the risks that are included in cooperating with too many of their most direct competitors.
Multiagent Approach for Public Transit System Based on Flexible Routes
Authors: Hadas Yuval , Ceder Avishai
Published: December 2008

The use of transfers in public transit has the advantages of reducing operational costs and introducing more flexible and efficient route planning. In contrast, the main drawback, from the passenger point of view, is the inconvenience of traveling multilegged trips. To diminish the waiting time caused by transfers, synchronized (timed) timetables were introduced. Their use, however, suffers from uncertainty about the simultaneous arrival of two (or more) vehicles at an existing stop. This can lead to deterioration in system reliability. To alleviate the uncertainty of simultaneous arrivals, a new passenger transfer concept was developed that extends the commonly used single-point encounter (at a single transit stop) to a road-segment encounter (any point along the road segment constituting a possible encounter point). The new concept is based on a multiagent system incorporating new models: (a) simulation-based models that describe the encounter probability of public transit vehicles along a road segment under dependent travel time conditions, (b) an optimization model based on distributed dynamic programming, and (c) a simulation model for the validation of the model. This multi-agent concept incorporates a low-complexity, near-optimal model that reduces the average travel time by 7% and increases the number of direct transfers by 285%.
Does Transit-Oriented Development Affect Metro Ridership?
Authors: Lin Jen-Jia , Shin Ting-Yu
Published: December 2008

A study was done to confirm the advantages of transit-oriented development (TOD) in increasing transit ridership and dispersing transit ridership distribution in a timely manner. To examine how the built environment of TOD influences the level and temporal distribution of metro ridership, 46 metro stations in Taipei City, Taiwan, China, were used as a sample, and cross-section analyses for 2004 were performed by using regression models and t-tests. Conclusions were reached on the basis of the empirical results. Daily ridership was positively affected by the floor-space area of the station areas, negatively affected by the percentage of four-way intersections, and insignificantly affected by mixed land use. Ridership dispersion in time was positively influenced by sidewalk length, negatively affected by retail and service floor-space area, and insignificantly influenced by density. The influences of density and pedestrian-friendly urban design on daily ridership differ significantly between weekdays and weekends, whereas the effects of all TOD characters on daily ridership dispersion differ significantly between weekdays and weekends. Finally, two potential applications of the empirical findings are discussed: TOD strategy directions corresponding to the studied cases and planning analysis for a specific station area.
Models for Safety Analysis of Road Surface Transit
Authors: Cheung Carl , Shalaby Amer S. , Persaud Bhagwant N. , Hadayeghi Alireza
Published: December 2008

A study was done to explore the development of zonal- and arterial-level collision prediction models that incorporate characteristics applicable to urban transit planning. A generalized linear modeling approach with a negative binomial regression error structure was employed by using a data set from Toronto, Ontario, Canada. The zonal-level models indicate that vehicle kilometers traveled, bus or streetcar kilometers traveled, arterial road kilometers, bus stop density, percentage of near-sided stops, and average posted speed have significant associations with occurrences of transit-involved collisions. The arterial-level models, which were developed for collisions involving all motor vehicles, suggest that average annual daily traffic, transit frequency, segment length, presence of on-street parking, and percentage of near-sided stops are all associated with increased frequency of these collisions, whereas percentage of far-sided stops and average stop spacing are linked with reduced collision frequency. It is evident that models such as those developed in this study can provide transit agencies with decision-support tools for considering safety implications in the strategic and service-planning processes. These models can also be used as a tool to predict future levels of transit-involved collisions for an existing and a new transportation network or arterial route.
Evolution and Effect of Transportation Policy on Public Transit
Authors: Ma Hong , Hadden-Loh Tracy , Yang Xinmiao , Sun Zhuangzhi , Shi Qixin
Published: December 2008

The United Nations predicts that half the world's population will live in cities by 2008. Thus, rapid urban sprawl, and especially its traffic congestion, is a global problem. Meeting mobility needs of urban dwellers is critical to sustaining growth and social stability, but many major cities struggle to do so. The evolving situation in Beijing, is examined, and the policy-making process in Beijing is analyzed to understand why transportation problems occur and are intractable and how they can be solved. A structure of policy making is proposed that includes four factors: institutional, travel behavior, ideals, and landmark events. The analysis includes a case study and comparison of transit service in Beijing and other cities, including results from the latest transit level-of-service rider survey in Beijing. It is concluded that an imbalance between transportation supply and demand is the primary cause of traffic congestion. The transportation problem must be solved from two sides: increasing supply and managing demand simultaneously. Public transit, paired with transportation demand management, is an effective approach for sustainable transportation but requires a range of policies.
Is Inadequate Transportation a Barrier to Community Involvement?
Authors: Hartell Ann M.
Published: December 2008

Since the publication of Robert Putnam's influential Bowling Alone, the concept of social capital has captured the attention of researchers in many disciplines. Policy makers and community advocates have pressed to include social capital in discussions about public policy, including transportation policy and planning. Using data from a national survey conducted in 2000, the study described in this paper investigated whether inadequate transportation is a barrier to people's involvement in their communities. The analysis uses a binary logistical model and finds that respondents who were female, who were nonwhite, who had household incomes less than $30,000, and who had long commutes to work had increased odds of citing transportation as a barrier. However, only 17% of the sample analyzed reported that transportation was a barrier. Most respondents cited other barriers along with transportation, most commonly, inflexible work schedules or inadequate child care. Although some types of improvements to transportation systems and transit service could improve access to community activities, the overall results suggest that if transportation improvements seek to dismantle barriers to community involvement, they will need to be combined with policies and programs that address other types of barriers to achieve a measurable positive effect. Travel demand management programs and better-coordinated transit service programs are two approaches to dismantling transportation barriers to community involvement.
Sociodemographic Groups and Mode Choice in a Middle-Sized European City
Authors: Bernetti Giulio , Longo Giovanni , Tomasella Lorenzo , Violin Alessia
Published: December 2008

This paper studies the transportation mode choice and the travel behaviors of different sociodemographic groups in a middle-sized European city. Data were extracted from an extensive origin–destination survey (10,092 individuals and 28,225 trips) conducted in Trieste, Italy, in 2002 and 2003. Gender, age, employment, and vehicle availability are important variables influencing transportation mode choice. These variables were explicitly introduced in the utility function of a random utility model, the multinomial logit model. The proposed model allows the effects of the different transportation planning initiatives on different socio-demographic groups to be evaluated. The effects of any transportation initiative may not affect the population as a whole and can be quite different for each sociodemographic group. These differences should be considered in assessments of any transportation planning process for two reasons: they improve the performance of the policy design phase and they increase the predictability of the effects caused by the transportation scenario chosen. Hence, the introduction of sociodemographic variables within a transportation mode choice model should be aimed not only at improving the statistical evaluation of the model but also at increasing its descriptive potential.
Does Urban Road Pricing Cause Hardship to Low-Income Car Drivers?
Authors: Cain Alasdair , Jones Peter M.
Published: December 2008

A major criticism of the principle of urban road pricing (also known as congestion charging and congestion pricing) is that it is regressive, namely, that the implementation of a charging scheme is likely to result in the imposition of a disproportionately large financial burden on low-income car users and their dependents, thereby resulting in hardship. A road pricing proposal in Edinburgh, Scotland, was used as a case study to assess the potential for road pricing-related hardship. Hardship occurs when people are denied access to basic needs. A quantitative definition of hardship was developed on the basis of an affordability measure derived from the utilities sector, supplemented by two additional conditions to account for the fact that transportation in itself is not a basic need. By using this definition, it was demonstrated that households in the lowest income quintile already spent an unaffordable proportion of their income on motoring costs, as much as about 40%, whereas the affordability threshold was 32.5%. The impact of a £2 (approximately $4 in 2008) charge on these low-income households would be negligible if it were paid less than once a week but would have a significant impact if it were paid four or more times a week, taking average aggregate motoring costs to above 50% of a low-income household's total disposable income. A simple regression analysis showed that of the five different basic needs identified in the research literature, work trips were the most likely to be linked to frequent congestion charge payment among low-income car users and, thus, the most likely to be linked to an additional risk of hardship.
Highway-Induced Development
Authors: Ewing Reid
Published: December 2008

In contrast to the literature on highway-induced traffic, the literature on highway-induced development has not been reviewed comprehensively. This review finds that in the post-Interstate era, major highway investments have small net effects on the growth and development of metropolitan areas, instead mostly moving development around the region to take advantage of improved accessibility. Highway-induced development is close to a zero-sum game. Highway investment patterns tend to favor suburbs over central cities and thereby contribute to decentralization and low-density development. Corridors receiving major highway investments experience land appreciation and therefore are likely to be developed at higher densities than developable lands outside the corridor. Highways may be necessary, but they are not sufficient, to induce development. To the extent that current planning and zoning caps hold, the impacts within the corridor will be moderated.
Sustainable Urban Policies for Developing Countries by Integrating Center-Based Telecommuting with Transit and Road Pricing
Authors: Dissanayake Dilum
Published: December 2008

This study investigates the suitability of integrating telecommuting with transit and road pricing for reducing traffic congestion and air pollution in developing countries. The application of disaggregate modeling to estimate the impacts of transportation policies—for instance, the reduction of vehicle kilometers of travel and air pollution levels—is the principal motivation for this study. First, a nested logit (NL) model was developed to investigate household travel behavior linked to vehicle ownership, mode choice, and trip-sharing attributes. The nest structure consists of two levels; the upper level characterizes car-owning, motorcycle-owning, and no-vehicle-owning choices, whereas the lower level represents household-related mode choices. Second, the estimated NL model is applied to the analysis of policies related to center-based telecommuting, transit, and road pricing. Several hypothetical satellite offices outside the central business district are considered to analyze the travel behavior associated with telecommuting. The new locations for the satellite offices were chosen on the basis of travel convenience and compatibility with the current road network. With center-based telecommuting as the base policy, several policies were investigated by combining the base policy with transit and road pricing. The policy impacts, including the reduction of vehicle kilometers of travel and air pollution, were estimated by using the Bangkok, Thailand, metropolitan region as a case study.
Indicators for Sustainable Transportation Planning
Authors: Johnston Robert A.
Published: December 2008

There is an ongoing debate worldwide about the indicators that policy makers should use to evaluate progress toward sustainable transportation systems. In general, studies of indicators lack an overall normative framework that allows decision makers or the public to make sense of the many overlapping and partial measures. A statewide urban growth model for California was run iteratively with the California statewide travel model to evaluate major transportation scenarios, such as freeway widening and high-speed rail. In addition, transportation and land use policies intended to provide more affordable housing accessible to jobs, widespread habitat protection, and strong reductions in greenhouse gas emissions were evaluated. This model provides many performance measures for travel, economic welfare and equity, rents paid, energy use, greenhouse gas emissions, vehicular air pollution, and habitat loss. A framework for interpreting these data on the basis of recent advances in the theories of well-being for individuals and nations is proposed. This theoretical framework for evaluating the model outputs used in planning also applies to the analysis of the empirical indicators used to track actual outcomes.