bluuebunny/crossref_metadata_2025 huggingface dataset:
The Contribution of Insurance Coverage and Community Resources to Reducing Racial/Ethnic Disparities in Access to Care
Authors: Hargraves J. Lee , Hadley Jack
Published: May 2003

Objective. To examine the extent to which health insurance coverage and available safety net resources reduced racial and ethnic disparities in access to care.

Data Sources. Nationally representative sample of 11,692 African American, 10,325 Hispanic, and 74,397 white persons. Nonelderly persons with public or private health insurance and those who were uninsured.

Study Design. Two cross‐sectional surveys of households conducted during 1996–1997 and 1998–1999.

Data Collection. Commonly used measures of access to and utilization of medical care were constructed for individuals. These measures include the following: (1) percent reporting unmet medical needs, (2) percent without a regular health care provider, and (3) no visit with a physician in the past year.

Findings. More than 6.5 percent of Hispanic and African Americans reported having unmet medical needs compared to less than 5.6 percent of white Americans. Hispanics were least likely to see the same doctor at their usual source of care (59 percent), compared to African Americans (66 percent) and whites (75 percent). Similarly, Hispanics were less likely than either African Americans or whites to have seen a doctor in the last year (65 percent compared to 76 percent or 79 percent). For Hispanics, more than 80 percent of the difference from whites was due to differences in measured characteristics (e.g., insurance coverage, income, and available safety net services). Differences in measured characteristics between African Americans and whites explained less than 80 percent of the access disparities.

Conclusion. Lack of health insurance was the single most important factor in white–Hispanic differences for all three measures and for two of the white–African American differences. Income differences were the second most important factor, with one exception. Community characteristics generally were much less important, with one exception. The positive effects of insurance coverage in reducing disparities outweigh benefits of increasing physician charity care or access to emergency rooms.
Length of Stay, Conditional Length of Stay, and Prolonged Stay in Pediatric Asthma
Authors: Silber Jeffrey H. , Rosenbaum Paul R. , Even‐Shoshan Orit , Shabbout Mayadah , Zhang Xuemei , Bradlow Eric T. , Marsh Roger R.
Published: May 2003

Objective. To understand differences in length of stay for asthma patients between New York State and Pennsylvania across children's and general hospitals in order to better guide policy.

Data Sources/Study Setting. All pediatric admissions for asthma in the states of Pennsylvania and New York using claims data obtained from each state for the years 1996–1998, n=38,310.

Study Design. A retrospective cohort design to model length of stay (LOS), the probability of prolonged stay, conditional length of stay (CLOS or the LOS after stay is prolonged), and the probability of readmission, controlling for patient factors, state, location and hospital type.

Analytic Methods. Logit models were used to estimate the probability of prolonged stay and readmission. The LOS and the CLOS were estimated with Cox regression. Model variables included comorbidities, income, race, distance from hospital, and insurance type. Prolonged stay was based on a Hollander‐Proschan “New‐Worse‐Than‐Used” test, corresponding to a three‐day stay.

Principal Findings. The LOS was longer in New York than Pennsylvania, and the probabilities of prolonged stay and readmission were much higher in New York than Pennsylvania. However, once an admission was prolonged, there were no differences in CLOS between states (when readmissions were not added to the LOS calculation). In both states, children's hospitals and general hospitals had similar adjusted LOS.

Conclusions. Management of asthma appears more efficient in Pennsylvania than New York: Less severe patients are discharged faster in Pennsylvania than New York; once discharged, patients are less likely to be readmitted in Pennsylvania than New York. However, once a stay is prolonged, there is little difference between New York and Pennsylvania, suggesting medical care for severely ill patients is similar across states. Differences between children's and general hospitals were small as compared to differences between states. We conclude that policy initiatives in New York, and other states, should focus their efforts on improving the care provided to less severe patients in order to help reduce overall length of stay.
Hospital Economics of the Hospitalist
Authors: Gregory Douglas , Baigelman Walter , Wilson Ira B
Published: May 2003

Objective To determine the economic impact on the hospital of a hospitalist program and to develop insights into the relative economic importance of variables such as reductions in mean length of stay and cost, improvements in throughput (patients discharged per unit time), payer methods of reimbursement, and the cost of the hospitalist program.

Data Sources The primary data source was Tufts‐New England Medical Center in Boston. Patient demographics, utilization, cost, and revenue data were obtained from the hospital's cost accounting system and medical records.

Study Design The hospitalist admitted and managed all patients during a six‐week period on the general medical unit of Tufts‐New England Medical Center. Reimbursement, cost, length of stay, and throughput outcomes during this period were contrasted with patients admitted to the unit in the same period in the prior year, in the preceding period, and in the following period.

Principal Findings The hospitalist group compared with the control group demonstrated: length of stay reduced to 2.19 days from 3.45 days (p<.001); total hospital costs per admission reduced to $1,775 from $2,332 (p<.001); costs per day increased to $811 from $679 (p<.001); no differences for readmission within 30 days of discharge to extended care facilities. The hospital's expected incremental profitability with the hospitalist was−$1.44 per admission excluding incremental throughput effects, and it was most sensitive to changes in the ratio of per diem to case rate reimbursement. Incremental throughput with the hospitalist was estimated at 266 patients annually with an associated incremental profitability of $1.3 million.

Conclusion Hospital interventions designed to reduce length of stay, such as the hospitalist, should be evaluated in terms of cost, throughput, and reimbursement effects. Excluding throughput effects, the hospitalist program was not economically viable due to the influence of per diem reimbursement. Throughput improvements occasioned by the hospitalist program with high baseline occupancy levels are substantial and tend to favor a hospitalist program.
Ability of Medicaid Claims Data to  Identify Incident Cases of Breast Cancer  in the Ohio Medicaid Population
Authors: Koroukian Siran M. , Cooper Gregory S. , Rimm Alfred A.
Published: May 2003

Background. The use of Medicaid data to study cancer‐related outcomes would be highly desirable. However, the accuracy of Medicaid claims data in the identification of incident cases of breast cancer is unknown.

Objectives. (1) To estimate the sensitivity of Medicaid claims data for case ascertainment of breast cancer; and (2) to determine the positive predictive value (PPV) of diagnostic and procedure codes retrieved from Medicaid claims, using the Ohio Cancer Incidence Surveillance System (OCISS) as the gold standard.

Methods. The study used the linked OCISS and Medicaid enrollment files, 1997–1998 (n=1,648). The claims search yielded 2,635 incident cases, of which 1,132 were also identified through the OCISS‐Medicaid files. Sensitivity and PPV of Medicaid data were calculated in subgroups of the population.

Results. The overall sensitivity was 68.7 percent, but varied greatly across the subgroups of the population. It was lower among women enrolled in Medicaid only for part of the study year than those enrolled in Medicaid for 12 months of the study year (56.7 percent and 78.0 percent respectively, p<0.0001), and lower among those who are dual Medicare‐Medicaid eligible compared to those not participating in the Medicare program (63.1 percent and 78.6 percent respectively, p<0.0001). The overall PPV was 43.0 percent, increasing up to 86.6 percent in the presence of procedure codes indicating the presence of mastectomy and lumpectomy, in addition to that of breast cancer diagnosis.

Conclusions. The sensitivity of Medicaid claims for case ascertainment of breast cancer is somewhat low, but improves considerably when accounting for women enrolled in Medicaid for the entire duration of the study year. The PPV is poor due to a high rate of false positives. The higher PPV obtained in the presence of procedure codes, in addition to diagnosis codes, will help researchers to correctly identify incident cases of breast cancer using Medicaid claims data.
Understanding Biased Selection in Medicare HMOs
Authors: Mello Michelle M. , Stearns Sally C. , Norton Edward C. , Ricketts Thomas C.
Published: May 2003

Objective To investigate the extent of favorable health maintenance organization (HMO) selection for a longitudinal cohort of Medicare beneficiaries, examine whether the extent of favorable selection varies with the degree of Medicare HMO market penetration in a county, and explain conflicting findings in the literature on favorable HMO selection.

Data Sources A panel of 1992–1996 data from the Medicare Current Beneficiary Survey (MCBS), supplemented with linked data from the Area Resource File and Medicare administrative datasets.

Study Design Using random effects probit estimation, we model a beneficiary's HMO enrollment status as a function of self‐reported health status and Medicare HMO market penetration.

Data Extraction Methods The MCBS data for beneficiaries residing in states served by Medicare HMOs in 1992–1996 were linked by county to the supplementary datasets.

Principal Findings We find that favorable selection persists in the cohort over time on some, but not all, measures. We find no substantial association between favorable HMO selection and HMO market penetration. We find that conflicting findings in the literature on favorable HMO selection may be explained by several methodological choices, including the choice of health status measure and the structure of the sample.

Conclusions Our results support further risk adjustment of the adjusted average per capita cost (AAPCC) payment formula.
Married in the Sight of God by Christian Batalden Scharen
Authors: Rercy Martyn
Published: May 2003

Reviewed by Rev. Wilton S., p.105 Haffey

Responce by Christian Batalden Scharen, p.109
Book Notes
Authors: Landau Yehezkel
Published: May 2003

Books reviewed:

Kathleen M. O’Connor, Lamentations and the Tears of the World
Evaluation of decompression safety in an occupational diving group using self reported diving exposure and health status
Authors: Doolette D J , Gorman D F
Published: May 2003

Background:Many occupational diving groups have substantially different diving patterns to those for which decompression schedules are validated.

Aims:To evaluate tuna farm occupational diving practice against existing decompression models and describe a method for collecting and modelling self reported field decompression data.

Methods:Machine readable objective depth/time profiles were obtained from depth/time recorders worn by tuna farm occupational divers. Divers’ health status was measured at the end of each working day using a self administered health survey that produces an interval diver health score (DHS) with possible values ranging from 0 to 30. Depth/time profiles were analysed according to existing decompression models. The contribution of diving exposure and between diver variability to DHS was evaluated using linear regression.

Results:The mean risk of decompression sickness was calculated as 0.005 (SD 0.003, n = 383). The mean DHS following diving was 3 (SD 2, n = 383) and following non-diving activities was 1 (SD 1, n = 41). After accounting for between diver variability in intercept, DHS was found to increase one unit for every 1% increase in the risk of decompression sickness.

Conclusions:A method has been established for the collection and analysis of self reported objective decompression data from occupational diving groups that can potentially be used as the basis for development of purpose designed occupational diving decompression schedules.
Evaluation of the quality of coding of job episodes collected by self questionnaires among French retired men for use in a job-exposure matrix
Authors: Pilorget C , Imbernon E , Goldberg M , Bonenfant S , Spyckerelle Y , Fournier B , Steinmetz J , Schmaus A
Published: May 2003

Background and Aims:The ESPACES study was intended to identify retirees who may have been, according to their job descriptions, exposed to asbestos during their working lives. As part of this study, we analysed the quality of the occupation and activity sector coding as well as its effect on the subjects’ exposure status.

Methods:The occupation and activity sector for a sample of 450 retired men were coded twice (with the second coder blinded to the first result), according to the international codes for industries (ISIC-1975) and occupations (ISCO-1968). For each series, linking the information about a job episode (dates, ISIC code, ISCO code) with the matrix allowed attribution of a probability of asbestos exposure to each episode and each subject. The asbestos exposure in the two series was compared by the kappa reproducibility coefficient.

Results:The analysis concerned 425 questionnaires. There was at least one difference in the code for either activity sector (ISIC) or occupation (ISCO) in half the episodes (50.2%). The exposure status estimated by the job-exposure matrix did not change between the series for 84.7% of the subjects. The kappa coefficient was 0.64 for all questionnaires, 0.70 when the questionnaire was coded twice by the same coder, and 0.62 when coded by two different coders.

Conclusions:Despite intra- and inter-differences between coders, the coding of job episodes for the ESPACES study appears satisfactory and hence indicates that the assessment of the subjects’ asbestos exposure was assessed without major distortions. This study underlines the usefulness of employing coders specifically trained for this technique.
Lung cancer mortality among chromate production workers
Authors: Luippold R S , Mundt K A , Austin R P , Liebig E , Panko J , Crump C , Crump K , Proctor D
Published: May 2003

Aims:To assess mortality in 1997 among 493 former workers of a US chromate production plant employed for at least one year between 1940 and 1972.

Methods:Cohort members were followed for mortality to 31 December 1997. Standardised mortality ratios (SMRs) were calculated for selected cause specific categories of death including lung cancer. Lung cancer mortality was investigated further by calculation of SMRs stratified by year of hire, duration of employment, time since hire, and categories of cumulative exposure to Cr(VI).

Results:Including 51 deaths due to lung cancer, 303 deaths occurred. SMRs were significantly increased for all causes combined (SMR = 129), all cancers combined (SMR = 155), and lung cancer (SMR = 241). A trend test showed a strong relation between lung cancer mortality and cumulative hexavalent exposure. Lung cancer mortality was increased for the highest cumulative exposure categories (⩾1.05 to <2.70 mg/m3-years, SMR = 365; ⩾2.70 to 23 mg/m3-years, SMR = 463), but not for the first three exposure groups. Significantly increased SMRs were also found for year of hire before 1960, 20 or more years of exposed employment, and latency of 20 or more years.

Conclusions:The finding of an increased risk of lung cancer mortality associated with Cr(VI) exposure is consistent with previous reports. Stratified analysis of lung cancer mortality by cumulative exposure suggests a possible threshold effect, as risk is significantly increased only at exposure levels over 1.05 mg/m3-years. Though a threshold is consistent with published toxicological evidence, this finding must be interpreted cautiously because the data are also consistent with a linear dose response.
A promise is a promise
Authors: Cummings K M
Published: May 2003

Philip Morris promised to “shut down instantly”if cigarettes were found to be harmful. Now that the company has admitted that “smoking causes lung cancer, heart disease, emphysema, and other serious diseases”, when will they keep their promise to stop making cigarettes?
Estimating the health consequences of replacing cigarettes with nicotine inhalers
Authors: Sumner W
Published: May 2003

Background:A fast acting, clean nicotine delivery system might substantially displace cigarettes. Public health consequences would depend on the subsequent prevalence of nicotine use, hazards of delivery systems, and intrinsic hazards of nicotine.

Methods:A spreadsheet program, DEMANDS, estimates differences in expected mortality, adjusted for nicotine delivery system features and prevalence of nicotine use, by extending the data and methods of the SAMMEC 3 software from the US Centers for Disease Control and Prevention. The user estimates disease risks attributable to nicotine, other smoke components, and risk factors that coexist with smoking. The public health consequences of a widely used clean nicotine inhaler replacing cigarettes were compared to historical observations and public health goals, using four different risk attribution scenarios and nicotine use prevalence from 0–100%.

Main outcome measures:Changes in years of potential life before age 85 (YPL85).

Results:If nicotine accounts for less than a third of smokers’ excess risk of SAMMEC diseases, as it most likely does, then even with very widespread use of clean nicotine DEMANDS predicts public health gains, relative to current tobacco use. Public health benefits accruing from a widely used clean nicotine inhaler probably equal or exceed the benefits of achieving Healthy People 2010 goals.

Conclusions:Clean nicotine inhalers might improve public health as much as any feasible tobacco control effort. Although the relevant risk estimates are somewhat uncertain, partial nicotine deregulation deserves consideration as part of a broad tobacco control policy.
Dimensions underlying legislator support for tobacco control policies
Authors: de Guia N A , Cohen J E , Ashley M J , Ferrence R , Rehm J , Studlar D T , Northrup D
Published: May 2003

Objective:To propose and test a new classification system for characterising legislator support for various tobacco control policies.

Design:Cross sectional study.

Subjects:Federal and provincial legislators in Canada serving as of October 1996 who participated in the Canadian Legislator Study (n = 553; response rate 54%).

Main outcome measures:A three factor model (Voters, Tobacco industry, Other interest groups) that assigns nine tobacco control policies according to legislators’ hypothesised perceptions of which group is more directly affected by these policies.

Results:Based on confirmatory factor analysis, the proposed model had an acceptable fit and showed construct validity. Multivariate analysis indicated that three of the predictors (believing that the government has a role in health promotion, being a non-smoker, and knowledge that there are more tobacco than alcohol caused deaths) were associated with all three factor scales. Several variables were associated with two of the three scales. Some were unique to each scale.

Conclusions:Based on our analyses, legislator support for tobacco control policies can be grouped according to our a priori factor model. The information gained from this work can help advocates understand how legislators think about different types of tobacco control policies. This could lead to the development of more effective advocacy strategies.
Development of a model of the tobacco industry’s interference with tobacco control programmes
Authors: Trochim W M K , Stillman F A , Clark P I , Schmitt C L
Published: May 2003

Objective:To construct a conceptual model of tobacco industry tactics to undermine tobacco control programmes for the purposes of: (1) developing measures to evaluate industry tactics, (2) improving tobacco control planning, and (3) supplementing current or future frameworks used to classify and analyse tobacco industry documents.

Design:Web based concept mapping was conducted, including expert brainstorming, sorting, and rating of statements describing industry tactics. Statistical analyses used multidimensional scaling and cluster analysis. Interpretation of the resulting maps was accomplished by an expert panel during a face-to-face meeting.

Subjects:34 experts, selected because of their previous encounters with industry resistance or because of their research into industry tactics, took part in some or all phases of the project.

Results:Maps with eight non-overlapping clusters in two dimensional space were developed, with importance ratings of the statements and clusters. Cluster and quadrant labels were agreed upon by the experts.

Conclusions:The conceptual maps summarise the tactics used by the industry and their relationships to each other, and suggest a possible hierarchy for measures that can be used in statistical modelling of industry tactics and for review of industry documents. Finally, the maps enable hypothesis of a likely progression of industry reactions as public health programmes become more successful, and therefore more threatening to industry profits.
Social exchange of cigarettes by youth
Authors: Forster J , Chen V , Blaine T , Perry C , Toomey T
Published: May 2003

Objective:This study seeks to determine the magnitude, nature, and correlates of social exchange of cigarettes among youth who smoke.

Design:Cross sectional survey.

Setting:Schools in 29 Minnesota communities.

Participants:All students in grades 8, 9, and 10 (ages 13–16 years) in each participating school. The parent/child response rate for the survey was 90%. Analyses included 4124 respondents who smoked at least one cigarette in the month before the survey.

Outcome measures:Social exchange scale, consisting of 16 items assessing aspects of social provision and acquisition of cigarettes.

Results:Almost 90% of youth in this study had obtained a cigarette from, and about 75% of them had provided cigarettes to, another teen in the prior month. Daily smokers provided to more teens and provided more often than those who smoked less than daily. Daily smokers also reported having more social sources, both teens and adults, than lighter smokers, and were more likely to have both bought from and sold cigarettes to other teens (p < 0.0001 for all comparisons between daily and less than daily smokers). In a multivariate analysis, social exchange was associated with grade, whether siblings and friends smoke, level of smoking, age of smoking initiation, parental influences and community norms about teen smoking, and buying cigarettes.

Conclusions:Social provision and acquisition of cigarettes among teens are widespread, reciprocal behaviours. Parental and community expectations about smoking influence social exchange, possibly by providing opportunities or barriers for social smoking. Commercial and social availability are not mutually exclusive; rather social exchange extends the reach of commercial sources.
A cluster randomised controlled trial of smoking cessation in pregnant women comparing interventions based on the transtheoretical (stages of change) model to standard care
Authors: Lawrence T , Aveyard P , Evans O , Cheng K K
Published: May 2003

Objectives:To evaluate the effectiveness in helping pregnant women stop smoking of two interventions (Pro-Change for a healthy pregnancy) based on the transtheoretical model of behaviour change (TTM) compared to current standard care.

Design:Cluster randomised trial.

Setting:Antenatal clinics in West Midlands, UK general practices.

Participants:918 pregnant smokers

Interventions:100 general practices were randomised into the three trial arms. Midwives in these practices delivered three interventions: A (standard care), B (TTM based self help manuals), and C (TTM based self help manuals plus sessions with an interactive computer program giving individualised smoking cessation advice).

Main outcome measures:Biochemically confirmed smoking cessation for 10 weeks previously, and point prevalence abstinence, both measured at 30 weeks of pregnancy and 10 days after delivery.

Results:There were small differences between the TTM arms. Combining the two arms, the odds ratios at 30 weeks were 2.09 (95% confidence interval (CI) 0.90 to 4.85) for 10 week sustained abstinence and 2.92 (95% CI 1.42 to 6.03) for point prevalence abstinence relative to controls. At 10 days after delivery, the odds ratios were 2.81 (95% CI 1.11 to 7.13) and 1.85 (95% CI 1.00 to 3.41) for 10 week and point prevalence abstinence respectively.

Conclusions:While there is a small borderline significant increase in quitting in the combined intervention arms compared with the controls, the effect of the intervention is small. At 30 weeks gestation and at 10 days postnatal, only about 3% of the intervention groups achieved sustained cessation, with numbers needed to treat of 67 (30 weeks of gestation) and 53 (10 weeks postnatal) for one additional woman to achieve sustained confirmed cessation. Given also that the intervention was resource intensive, it is of doubtful benefit.
How tobacco companies ensure prime placement of their advertising and products in stores: interviews with retailers about tobacco company incentive programmes
Authors: Feighery E C , Ribisl K M , Clark P I , Haladjian H H
Published: May 2003

Background:About 81% of cigarette manufacturers’ marketing expenditures in the USA is spent to promote cigarette sales in stores. Relatively little is known about how these expenditures help the manufacturers achieve their marketing goals in stores. A better understanding of how tobacco companies influence the retail environment would help researchers and tobacco control activists to monitor industry presence in stores.

Objective:To describe the types of tobacco company incentive programmes offered to retailers, how these programmes impact the store environments, and possible visual indicators of retailer participation in incentive programmes.

Study design:In-depth qualitative interviews with a convenience sample of 29 tobacco retailers were conducted in 2001.

Setting:USA.

Main outcome measures:The types and requirements of retailer incentive programmes provided by tobacco companies, and how participation in a programme alters their stores.

Results:The retailers provided insights into how tobacco companies convey promotional allowances and special offers to them and how these incentives shape the retail environment. Retailers noted that tobacco companies exert substantial control over their stores by requiring placement of products in the most visible locations, and of specific amounts and types of advertising in prime locations in the store. Retailers also described how tobacco companies reduce prices by offering them volume based discounts, “buy two, get one free” specials, and “buying down” the price of existing product.

Conclusions:Tobacco companies are concentrating their marketing dollars at the point-of-sale to the extent that the store is their primary communication channel with customers. As a result, all shoppers regardless of age or smoking status are exposed to pro-smoking messages. Given the financial resources spent by tobacco companies in stores, this venue warrants closer scrutiny by researchers and tobacco control advocates.
The descriptive epidemiology of local restaurant smoking regulations in Massachusetts: an analysis of the protection of restaurant customers and workers
Authors: Skeer M , Siegel M
Published: May 2003

Objectives:To describe the range of restaurant smoking regulations in the 351 cities and towns in Massachusetts, and to analyse the level of protection from secondhand smoke exposure guaranteed by these regulations.

Design:We obtained the local restaurant smoking regulations for each town, analysing them in terms of the protection of restaurant workers, bar workers, and adult and youth restaurant customers.

Main outcome measure:The percentage of restaurant patrons and workers and bar workers who are protected from secondhand smoke exposure by the current smoking regulations in Massachusetts.

Results:As of June 2002, 225 towns had local restaurant smoking regulations. Of these, 69 (30.7%) do not allow smoking in restaurants, 10 (4.4%) restrict smoking to adult only restaurants, 64 (28.4%) restrict smoking to enclosed, separately ventilated areas, and 82 (36.4%) restrict smoking to areas that need not be enclosed and separately ventilated. Of the 174 towns that, at a minimum, restrict smoking to bar areas or separately ventilated areas, 35 (20.1%) allow variances. Overall, 60 towns, covering only 17.7% of the population, completely ban smoking in restaurants. As a result, 81.3% of adult restaurant customers, 81.2% of youth customers, 82.3% of restaurant workers, and 87.0% of bar workers are not guaranteed protection from secondhand smoke in restaurants.

Conclusions:Despite the widespread adoption of local restaurant smoking regulations in Massachusetts, the majority of restaurant customers and workers remain unprotected from secondhand smoke exposure. In light of this, public health practitioners must stop compromising the protection of customers and workers from secondhand smoke exposure in restaurants.
The impact of learning of a genetic predisposition to nicotine dependence: an analogue study: Table 1
Authors: Wright A J , Weinman J , Marteau T M
Published: May 2003

Objectives:To examine the consequences of informing smokers of a genetic predisposition to nicotine dependence and of providing treatment efficacy information tailored to genetic status.

Design:Analogue study using four vignettes; 2 (genetic status) × 2 (whether treatment efficacy information provided) between subjects design.

Participants:269 British adult smokers.

Outcome measures:Preferred cessation methods and perceived control over quitting.

Results:Gene positive participants were significantly more likely to choose the cessation method described as effective for their genetic status, but significantly less likely to choose to use their own willpower. Providing tailored treatment information did not alter these effects. Perceived control was not significantly affected by either genetic status or information provision.

Conclusions:Learning of a genetic predisposition to nicotine dependence may increase desire for effective cessation methods, but may undermine the perceived importance of willpower in stopping smoking.
Smoking and gambling: a trance inducing ritual: Figure 1
Authors: Harper T
Published: May 2003

“Smoking is a powerful re-inforcement for the trance-inducing rituals associated with gambling.”
RIEMANNIAN GEOMETRICAL OPTICS: SURFACE WAVES IN DIFFRACTIVE SCATTERING
Authors: DE MICHELI E. , BRAGADIN G. MONTI , VIANO G. A.
Published: May 2003

The geometrical diffraction theory, in the sense of Keller, is here reconsidered as an obstacle problem in the Riemannian geometry. The first result is the proof of the existence and the analysis of the main properties of the "diffracted rays", which follow from the non-uniqueness of the Cauchy problem for geodesics in a Riemannian manifold with boundary. Then, the axial caustic is here regarded as a conjugate locus, in the sense of the Riemannian geometry, and the results of the Morse theory can be applied. The methods of the algebraic topology allow us to introduce the homotopy classes of diffracted rays. These geometrical results are related to the asymptotic approximations of a solution of a boundary value problem for the reduced wave equation. In particular, we connect the results of the Morse theory to the Maslov construction, which is used to obtain the uniformization of the asymptotic approximations. Then, the border of the diffracting body is the envelope of the diffracted rays and, instead of the standard saddle point method, use is made of the procedure of Chester, Friedman and Ursell to derive the damping factors associated with the rays which propagate along the boundary. Finally, the amplitude of the diffracted rays when the diffracting body is an opaque sphere is explicitly calculated.
ENHANCING STABILITY OF LATTICE-BOLTZMANN SIMULATIONS VIA NEW BOUNDARY CONDITIONS
Authors: DE LA FUENTE LORENZO , INGRAM DAVID , MINGHAM CLIVE , CAUSON DEREK , HE XIAO-YI
Published: May 2003

A new boundary condition is developed to enhance numerical stability for moving walls in lattice-Boltzmann simulations. It includes a population "adjustment" procedure at boundaries which allows stable simulations closer to the theoretical limit of τ = 0.5. Couette and lid-driven cavity flow simulations show improved velocity profiles, lower stable relaxation timestep τ and higher Reynolds number Re limits. The new method needs fewer timesteps to achieve steady-state.
MATHEMATICA™ PACKAGES FOR COMPUTING PRINCIPAL DECOMPOSITIONS OF SIMPLE LIE ALGEBRAS AND APPLICATIONS IN EXTENDED CONFORMAL FIELD THEORIES
Authors: GĂRĂJEU DANIELA , GĂRĂJEU MIHAIL
Published: May 2003

In this article, we propose two Mathematica™ packages for doing calculations in the domain of classical simple Lie algebras.

The main goal of the first package, [Formula: see text], is to determine the principal three-dimensional subalgebra of a simple Lie algebra. The package provides several functions which give some elements related to simple Lie algebras (generators in fundamental and adjoint representation, roots, Killing form, Cartan matrix, etc.).

The second package, [Formula: see text], concerns the principal decomposition of a Lie algebra with respect to the principal three-dimensional embedding.

These packages have important applications in extended two-dimensional conformal field theories. As an example, we present an application in the context of the theory of W-gravity.
ARE SOCIAL STRUCTURES DETERMINED BY THE ECONOMY?
Authors: CORSO G. , LUCENA L. S. , THOMÉ Z. D.
Published: May 2003

We simulate the interplay between productive and financial activity using a model that considers equal opportunities among individuals of a society. As the simulation evolves in time, three qualitative wealth distribution profiles are generated according to the flux of productive capital. We relate these curves to different socioeconomic structures: a primitive equalitarian society; a medieval society having a distribution of wealth with castes and discontinuities; and a modern society where this distribution is roughly exponential.
NUCLEATION AND METASTABILITY IN THE CO2 SYSTEM
Authors: HEERMANN DIETER W. , WANG TING , LEE WEI-DER
Published: May 2003

We have investigated metastability and nucleation in the CO 2 system. To facilitate comparison with experiment and analytical theories, we have also calculated the coexistence curve. The metastability properties were computed using three methods to calculate the compressibility: droplet distribution, density fluctuations, and structure factor. These provide three measures for the time-dependent compressibility. If the compressibility showed a window in which it was quasi time-independent, for the observation period we categorized the quench to lead into a metastable state. Our fully atomistic simulation shows that the metastable region is extremely small. Already, very shallow quenches into the two-phase region have given rise to nonclassical behavior. The calculated pseudo spinodal is located far from the mean field expectation.
STRUCTURE OF ENERGY LANDSCAPE OF SHORT PEPTIDES
Authors: ARKIN HANDAN , ÇELİK TARIK
Published: May 2003

We have simulated, as a showcase, the pentapeptide Met-enkephalin (Tyr-Gly-Gly-Phe-Met) to visualize the energy landscape and to investigate the conformational coverage by the multicanonical method. We obtained a three-dimensional topographic picture of the whole energy landscape by plotting the histogram with respect to energy (temperature) and the order parameter, which gives the degree of resemblance of any created conformation with the global energy minimum.
CORRELATION PROPERTIES OF PROTEIN SEQUENCES OF DIFFERENT STRUCTURAL CLASSES
Authors: HUANG MIN , XIAO YI
Published: May 2003

We analyze the amino acid sequences of the proteins of different structural classes using the method of power spectrum density. It was found that the protein hydrophobicity sequences of different structural classes show different significant periodicity, which relates closely to the order of the α-helices and β-strands in their polypeptide chains.
IMPLICIT SIMULATIONS USING MESSAGING PROTOCOLS
Authors: KOHRING G. A.
Published: May 2003

A novel algorithm for performing parallel, distributed computer simulations on the Internet using Internet protocol (IP) control messages is introduced. The algorithm employs carefully constructed Internet control message protocol (ICMP) packets that enable the required computations to be completed as part of the standard IP communication protocol. After providing a detailed description of the algorithm, experimental applications in the areas of stochastic neural networks and deterministic cellular automata are discussed. As an example of the algorithm's potential power, a simulation of a deterministic cellular automaton involving 105 Internet-connected devices was performed.
NEW ENVELOPE SOLUTIONS FOR COMPLEX NONLINEARSCHRÖDINGER+EQUATION VIA SYMBOLIC COMPUTATION
Authors: YAN ZHEN-YA
Published: May 2003

With the aid of symbolic computation, an extended Jacobian elliptic function expansion method is further extended to the complex nonlinear Schrödinger+equation. As a result, 24 families of the envelope doubly-periodic solutions with Jacobian elliptic functions are obtained. When the modulus m → 1 or zero, the corresponding six envelope solitary wave solutions and six envelope singly-periodic (trigonometric function) solutions are also found. This powerful method can also be applied to other equations, such as the nonlinear Schrödinger equation and Zakharov equation.
CALCULATING MEAN EXCITATION ENERGY FROM SHANNON INFORMATION ENTROPY FOR K–Xe ATOMS
Authors: SOLIMANNEJAD M. , PAKIARI A. H.
Published: May 2003

The calculation of the Shannon entropy of Hartree–Fock electron density is reported for the K–Xe atoms in the fourth and fifth rows of the periodic table in the ground state. In local plasma approximation, the Shannon entropy calculated is used directly to estimate mean excitation energies. To our knowledge, the mean excitation energies of K–Xe atoms are presented here for the first time.
SIMULATING MALE SELFISH STRATEGY IN REPRODUCTION DISPUTE
Authors: DE OLIVEIRA P. M. C. , MOSS DE OLIVEIRA S.
Published: May 2003

We introduce into the Penna Model of biological aging a mechanism to maximize the ability of a sperm to compete with those of other males. Such a selfish mechanism increases the rate of success of male reproduction, but may decrease the survival probability of the female population, depending on its mode of action. We also find a dynamic phase transition induced by the existence of an absorbing state, where no selfish males survive.
PHASE TRANSITION IN HIERARCHY MODEL OF BONABEAU
Authors: STAUFFER DIETRICH
Published: May 2003

The model of Bonabeau explains the emergence of social hierarchies from the memory of fights in an initially egalitarian society. Introducing a feedback from the social inequality into the probability to win a fight, we find a sharp transition between an egalitarian society at low population density and a hierarchical society at high population density.
eTIFIS: AN INNOVATIVE e-FORECASTING WEB APPLICATION
Authors: TAVANIDOU E. , NIKOLOPOULOS K. , METAXIOTIS K. , ASSIMAKOPOULOS V.
Published: May 2003

The Internet platform has become the most popular one to build integrated applications. This paper describes the design and implementation of an innovative e-Forecasting application over the Internet. The application delivers timeseries' forecasts on-line via the Internet. The user can choose amongst classic forecasting techniques including the Theta model. This study discusses why such an application is innovative and interesting to the IT community. The architecture which is proposed implements an advanced e-forecasting application and also offers web-service interfaces for third party applications. This dual functionality of the proposed architecture makes it extensible and rigid.
SOFTARCH: TOOL SUPPORT FOR INTEGRATED SOFTWARE ARCHITECTURE DEVELOPMENT
Authors: GRUNDY JOHN , HOSKING JOHN
Published: May 2003

A good software architecture design is crucial in successfully realising an object-oriented analysis (OOA) specification with an object-oriented design (OOD) model that meets the specification's functional and non-functional requirements. Most CASE tools and software architecture design notations do not adequately support software architecture modelling and analysis, integration with OOA and OOD methods and tools, and high-level, dynamic architectural visualisations of running systems. We describe SoftArch, an environment that provides flexible software architecture modelling using a concept of successive refinement and an extensible architecture meta-model. SoftArch provides extensible analysis tools enabling developers to analyse their architecture model properties. Run-time visualisation of systems uses dynamic annotation and animation of high-level architectural modelling views. SoftArch is integrated with a component-based CASE tool and run-time monitoring tool, and has facilities for 3rd party tool integration through a common exchange format. This paper discusses the motivation for SoftArch, its modelling, analysis and dynamic visualisation capabilities, and its integration with various analysis, design and implementation tools.
A BUSINESS PROCESS CENTERED SOFTWARE ANALYSIS METHOD
Authors: LI JINGZHOU , MAGUIRE BRIEN , YAO YIYU
Published: May 2003

Based on the requirements arising from process-centered organizations and because of the lack of process modeling mechanisms in traditional software development methods, this paper presents a Business Process-centered Software Analysis method (BPSA), which supports the modeling of business process control logic. As a method, BPSA is composed of two main parts: a model and the steps of how to model the requirements using this model. The model includes the functional, informational and organizational aspects as well as the behavioral aspect that provides the mechanism for modeling the process control logic. The event mechanism is employed in this method as a main technique for modeling the control aspect of business processes. This method is based on technologies such as Structured Analysis, OOA & OOD, Workflow, XML, and has been used in the development of several medium and large information systems, proving to be both useful and effective.
A LAYERED METAMODEL FOR HIERARCHICAL MODELING IN UML
Authors: SONG CHEE-YANG , BAIK DOO-KWON
Published: May 2003

As software is becoming larger and more complex, it is increasingly important to use the hierarchical modeling approach. Unfortunately, however, UML does not specify each metamodel with hierarchy for model by modeling phase. Thus, most UML-based methodologies do not address the hierarchical modeling for model. As a method for supporting hierarchical modeling on UML, this paper proposes a layered metamodel which defines hierarchically modeling elements of model according to the modeling phase. We describe each metamodel with hierarchy for models in UML, then present the hierarchical integrated metamodel combined with each metamodel by three modeling phases (conceptual phase, specific phase, and concrete phase). Therefore, designers are able to construct the hierarchical model by applying the metamodel with hierarchy. Using the hierarchical metamodel enables designers to improve the usability of UML and reusability of application model.
A TOOL FOR CREATING DESIGN MODELS FROM WEB SITE CODE
Authors: PAGANELLI L. , PATERNÓ F.
Published: May 2003

In this paper we present a method and the related tool for analysing Web site code in order to automatically reconstruct the underlying logical interaction design. Such design is represented through task models that describe how activities should be performed to reach users' goals. The models also include a specification of the objects that should be manipulated to accomplish such tasks. We also discuss how the result of this reverse engineering process can be provided as input to a number of tools for various purposes (model analysis, usability evaluation, user interface redesign for different interactive platforms).
SUPPLIER SELECTION BASED ON BOOTSTRAP CONFIDENCE REGIONS OF PROCESS CAPABILITY INDICES
Authors: POLANSKY ALAN M.
Published: May 2003

The supplier selection problem consists of selecting the best of several possible suppliers for a product. The selection criteria, in the absence of considerations such as cost, are based on a quality metric such as the capability of the supplier's manufacturing process. Because quality metrics are estimated based on sample process data, the inherent variability in the estimates must be accounted for when selecting the best supplier. In this paper we consider a methodology based on the bootstrap that assigns confidence levels to each of the suppliers. These confidence levels are designed to reflect the amount of confidence we have that the supplier actually has the best quality metric, conditional on the observed samples. The methodology is demonstrated using two examples.
MAXIMUM LIKELIHOOD ESTIMATES FOR THE HYPERGEOMETRIC SOFTWARE RELIABILITY MODEL
Authors: PADBERG FRANK
Published: May 2003

We present a fast and exact novel algorithm to compute maximum likelihood estimates for the number of defects initially contained in a software, using the hypergeometric software reliability model. The algorithm is based on a rigorous and comprehensive mathematical analysis of the growth behavior of the likelihood function for the hypergeometric model. We also study a numerical example taken from the literature and compare the estimate obtained in the hypergeometric model with the estimates obtained in other reliability models. The hypergeometric estimate is highly accurate.
A SURVEY ON DISCRETE LIFETIME DISTRIBUTIONS
Authors: BRACQUEMOND CYRIL , GAUDOIN OLIVIER
Published: May 2003

This paper presents a comprehensive survey of discrete probability distributions used in reliability for modeling discrete lifetimes of nonrepairable systems. The basic properties of each model are given. A classification into two families is proposed, highlighting the interest of using a Pólya urn scheme. The quality of the estimation of models parameters is numerically assessed. Some criteria are given in order to select among the presented distributions the most useful for applications.
HUMAN ERROR IN HEALTH CARE SYSTEMS: BIBLIOGRAPHY
Authors: DHILLON B. S. , RAJENDRAN MUTHURAMAN
Published: May 2003

This paper briefly discusses the subject of human error in health care systems and presents a comprehensive list of references on the said subject.