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Salt marshes act as natural barriers that reduce wave energy during storm events and help protect coastal communities located in low-lying areas. This ecosystem can be an important asset for climate adaptation due to its particular capability of vertically accrete to adjust to long-term changes in water levels. Therefore, understanding marsh protection benefits thresholds in the face of sea-level rise (SLR) is important for planning future climate adaptation. In this context, the main goal of this manuscript is to examine how the storm protection benefits provided by salt marshes might evolve under SLR projections with different probability levels and emission pathways. In this study, a modeling framework that employs marsh migration predictions from the Sea Level Affecting Marshes Model (SLAMM) as parameterization into a hydrodynamic and wave model (ADCIRC + SWAN) was utilized to explicitly represent wave attenuation by vegetation under storm surge conditions. SLAMM predictions indicate that the SLR scenario, a combination of probability level and emission pathways, plays a substantial role in determining future marsh migration or marsh area loss. For example, results based on the 50% probability, stabilized emissions scenario show an increase of 45% in the marsh area on Maryland's Lower Eastern Shore by 2100, whereas Dorchester County alone could experience a 75% reduction in total salt marsh areas by 2100 under the 1% probability, growing emissions scenario. ADCIRC + SWAN results using SLAMM land cover and elevation outputs indicate that distinct temporal thresholds emerge where marsh extent sharply decreases and wave heights increase, especially after 2050, and exacerbates further after 2080. These findings can be utilized for guiding environmental policies and to aid informed decisions and actions in response to SLR-driven environmental changes., (© 2024. The Author(s).)

The Chesapeake Bay watershed encompasses six states and the District of Columbia. Consequently, the people within it display great diversity in terms of values, allegiances, and experiences. That diversity may help to explain an apparent inability to coordinate actions aimed at redressing the dismal water quality throughout the watershed. In this paper, we bridge theory to an applied scenario to examine the importance of developing a collective identity within the watershed to bring about changes in individual behavior and policies. We present the current conditions of the Chesapeake Bay watershed, propose a stage model for the development of a collective watershed identity, outline theoretically grounded determinants of each stage, and discuss the challenges in developing a collective identity. We further suggest several guiding questions for future research., (© 2024. The Author(s).)

Introduction: HIV prevalence is high among men who have sex with men (MSM) in Baltimore, Maryland, United States, and the levels of viral suppression among HIV‐positive MSM are relatively low. The HIV Prevention Trials Network 078 trial seeks to increase the levels of viral suppression among US MSM by increasing the rates of diagnosis and linkage to care and treatment. We estimated the increases in viral suppression needed to reach different HIV incidence reduction targets, and the impact of meeting diagnosis and treatment targets. Methods: We used a mathematical model of HIV transmission among MSM from Baltimore, US, parameterised with behavioural data and fitted to HIV prevalence and care continuum data for Baltimore wherever possible, to project increases in viral suppression needed to reduce the HIV incidence rate among Baltimore MSM by 10, 20, 30 or 50% after 2, 5 and 10 years. We also projected HIV incidence reductions achieved if US national targets – 90% of people living with HIV (PLHIV) know their HIV serostatus, 90% of those diagnosed are retained in HIV medical care and 80% of those diagnosed are virally suppressed – or UNAIDS 90‐90‐90 targets (90% of PLHIV know their status, 90% of those diagnosed receive antiretroviral therapy (ART), 90% of those receiving ART are virally suppressed) are each met by 2020. Results: To reduce the HIV incidence rate by 20% and 50% after five years (compared with the base‐case at the same time point), the proportion of all HIV‐positive MSM who are virally suppressed must increase above 2015 levels by a median 13 percentage points (95% uncertainty interval 9 to 16 percentage points) from median 49% to 60%, and 27 percentage points (22 to 35) from 49% to 75% respectively. Meeting all three US or 90‐90‐90 UNAIDS targets results in a 48% (31% to 63%) and 51% (38% to 65%) HIV incidence rate reduction in 2020 respectively. Conclusions: Substantial improvements in levels of viral suppression will be needed to achieve significant incidence reductions among MSM in Baltimore, and to meet 2020 US and UNAIDS targets. Future modelling studies should additionally consider the impact of pre‐exposure prophylaxis for MSM. [ABSTRACT FROM AUTHOR]

Vibrio parahaemolyticus is a leading cause of seafood-borne gastroenteritis. Given its natural presence in brackish waters, there is a need to develop operational forecast models that can sufficiently predict the bacterium's spatial and temporal variation. This work attempted to develop V. parahaemolyticus prediction models using frequently measured time-indexed and -lagged water quality measures. Models were built using a large data set ( n  = 1,043) of surface water samples from 2007 to 2010 previously analyzed for V. parahaemolyticus in the Chesapeake Bay. Water quality variables were classified as time indexed, 1-month lag, and 2-month lag. Tobit regression models were used to account for V. parahaemolyticus measures below the limit of quantification and to simultaneously estimate the presence and abundance of the bacterium. Models were evaluated using cross-validation and metrics that quantify prediction bias and uncertainty. Presence classification models containing only one type of water quality parameter (e.g., temperature) performed poorly, while models with additional water quality parameters (i.e., salinity, clarity, and dissolved oxygen) performed well. Lagged variable models performed similarly to time-indexed models, and lagged variables occasionally contained a predictive power that was independent of or superior to that of time-indexed variables. Abundance estimation models were less effective, primarily due to a restricted number of samples with abundances above the limit of quantification. These findings indicate that an operational in situ prediction model is attainable but will require a variety of water quality measurements and that lagged measurements will be particularly useful for forecasting. Future work will expand variable selection for prediction models and extend the spatial-temporal extent of predictions by using geostatistical interpolation techniques. IMPORTANCE Vibrio parahaemolyticus is one of the leading causes of seafood-borne illness in the United States and across the globe. Exposure often occurs from the consumption of raw shellfish. Despite public health concerns, there have been only sporadic efforts to develop environmental prediction and forecast models for the bacterium preharvest. This analysis used commonly sampled water quality measurements of temperature, salinity, dissolved oxygen, and clarity to develop models for V. parahaemolyticus in surface water. Predictors also included measurements taken months before water was tested for the bacterium. Results revealed that the use of multiple water quality measurements is necessary for satisfactory prediction performance, challenging current efforts to manage the risk of infection based upon water temperature alone. The results also highlight the potential advantage of including historical water quality measurements. This analysis shows promise and lays the groundwork for future operational prediction and forecast models., (Copyright © 2019 Davis et al.)

Objectives: Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT) increase the risk of HIV transmission among men who have sex with men (MSM). Diagnosis of NG/CT may provide an efficient entry point for prevention of HIV through the delivery of pre-exposure prophylaxis (PrEP); however, the additional population-level impact of targeting PrEP to MSM diagnosed with NG/CT is unknown., Design: An agent-based simulation model of NG/CT and HIV cocirculation among MSM calibrated against census data, disease surveillance reports and the US National HIV Behavioral Surveillance study., Setting: Baltimore City, Maryland, USA., Interventions: PrEP implementation was modelled under three alternative scenarios: (1) PrEP delivery at NG/CT diagnosis (targeted delivery), (2) PrEP evaluation at NG/CT screening/testing and (3) PrEP evaluation in the general community (untargeted)., Main Outcome: The projected incidence of HIV after 20 years of PrEP delivery under two alternatives: when equal numbers of MSM are (1) screened for PrEP or (2) receive PrEP in each year., Results: Assuming 60% uptake and 60% adherence, targeting PrEP to MSM diagnosed with NG/CT could reduce HIV incidence among MSM in Baltimore City by 12.4% (95% uncertainty range (UR) 10.3% to 14.4%) in 20 years, relative to no PrEP. Expanding the coverage of NG/CT screening (such that individuals experience a 50% annual probability of NG/CT screening and evaluation for PrEP on NG/CT diagnosis) can further increase the impact of targeted PrEP to generate a 22.0% (95% UR 20.1% to 23.9%) reduction in HIV incidence within 20 years. When compared with alternative implementation scenarios, PrEP evaluation at NG/CT diagnosis increased impact of PrEP on HIV incidence by 1.5(95% UR 1.1 to 1.9) times relative to a scenario in which PrEP evaluation happened at the time of NG/CT screening/testing and by 1.6 (95% UR 1.2 to 2.2) times relative to evaluating random MSM from the community., Conclusions: Targeting MSM infected with NG/CT increases the efficiency and effectiveness of PrEP delivery. If high levels of sexually transmitted infection screening can be achieved at the community level, NG/CT diagnosis may be a highly effective entry point for PrEP initialisation., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Introduction Electronic dance music (EDM) festivals represent a unique subset of mass-gathering events with limited guidance through literature or legislation to guide mass-gathering medical care at these events. Hypothesis/Problem Electronic dance music festivals pose unique challenges with increased patient encounters and heightened patient acuity under-estimated by current validated casualty predication models., Methods: This was a retrospective review of three separate EDM festivals with analysis of patient encounters and patient transport rates. Data obtained were inserted into the predictive Arbon and Hartman models to determine estimated patient presentation rate and patient transport rates., Results: The Arbon model under-predicted the number of patient encounters and the number of patient transports for all three festivals, while the Hartman model under-predicted the number of patient encounters at one festival and over-predicted the number of encounters at the other two festivals. The Hartman model over-predicted patient transport rates for two of the three festivals., Conclusion: Electronic dance music festivals often involve distinct challenges and current predictive models are inaccurate for planning these events. The formation of a cohesive incident action plan will assist in addressing these challenges and lead to the collection of more uniform data metrics. FitzGibbon KM , Nable JV , Ayd B , Lawner BJ , Comer AC , Lichenstein R , Levy MJ , Seaman KG , Bussey I . Mass-gathering medical care in electronic dance music festivals. Prehosp Disaster Med. 2017;32(5):563-567.

From the 1930s through the 1940s, Lowell Reed and Wade Hampton Frost used mathematical models and mechanical epidemic simulators as research tools and to teach epidemic theory to students at the Johns Hopkins Bloomberg School of Public Health (then the School of Hygiene and Public Health). Since that time, modeling has become an integral part of epidemiology and public health. Models have been used for explanatory and inferential purposes, as well as in planning and implementing public health responses. In this article, we review a selection of developments in the history of modeling of infectious disease dynamics over the past 100 years. We also identify trends in model development and use and speculate as to the future use of models in infectious disease dynamics., (© The Author 2016. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Manual traffic control is an intersection control strategy in which law enforcement officers allocate intersection right-of-way to turning movements. Many emergency traffic management plans call for manual traffic control in response to oversaturated roadway conditions. This is because it is thought to more effectively move traffic during temporary surges in demand. The goal of this research was to evaluate the current state-of-the-practice used by the Army Corps of Engineers (ACE) in selecting intersections for manual traffic control and allocating police personnel to them during emergencies. This research uses the emergency traffic management plans developed by the ACE for nine counties in the Maryland Eastern Shore region. This area encompassing 14,318 intersections of which 74 were selected for manual traffic control during emergencies. This work sought to quantify the correlations that exist between intersection attributes and the ACE' decision to allocate officers to control them. The research findings suggest that US routes, State routes, and emergency evacuation routes are statistically significant in determining the need for police control at intersections. Also significant are intersection on contraflow corridors and intersections near grade separated interchanges. The model also determined that intersections isolated from evacuation routes and county exits were more likely to be selected for manual control, indicating that rural areas may rely on manual traffic control in the absence of multilane highway and freeways. This research also found that intersections involving evacuation routes, contraflow corridors, and grade separated interchanges may warrant additional police personnel (two or more officers) for manual traffic control.

Background: Although working smoke alarms halve deaths in residential fires, many households do not keep alarms operational. We tested whether theory-based education increases alarm operability., Methods: Randomised multiarm trial, with a single arm randomly selected for use each day, in low-income neighbourhoods in Maryland, USA. Intervention arms: (1) Full Education combining a health belief module with a social-cognitive theory module that provided hands-on practice installing alarm batteries and using the alarm's hush button; (2) Hands-on Practice social-cognitive module supplemented by typical fire department education; (3) Current Norm receiving typical fire department education only. Four hundred and thirty-six homes recruited through churches or by knocking on doors in 2005-2008. Follow-up visits checked alarm operability in 370 homes (85%) 1-3.5 years after installation., Main Outcome Measures: number of homes with working alarms defined as alarms with working batteries or hard-wired and number of working alarms per home. Regressions controlled for alarm status preintervention; demographics and beliefs about fire risks and alarm effectiveness., Results: Homes in the Full Education and Practice arms were more likely to have a functioning smoke alarm at follow-up (OR=2.77, 95% CI 1.09 to 7.03) and had an average of 0.32 more working alarms per home (95% CI 0.09 to 0.56). Working alarms per home rose 16%. Full Education and Practice had similar effectiveness (p=0.97 on both outcome measures)., Conclusions: Without exceeding typical fire department installation time, installers can achieve greater smoke alarm operability. Hands-on practice is key. Two years after installation, for every three homes that received hands-on practice, one had an additional working alarm., Trial Registration Number: http://www.clinicaltrials.gov number NCT00139126., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Understanding variation in stream thermal regimes becomes increasingly important as the climate changes and aquatic biota approach their thermal limits. We used data from paired air and water temperature loggers to develop region-scale and stream-specific models of average daily water temperature and to explore thermal sensitivities, the slopes of air-water temperature regressions, of mostly forested streams across Maryland, USA. The region-scale stream temperature model explained nearly 90 % of the variation (root mean square error = 0.957 °C), with the mostly flat coastal plain streams having significantly higher thermal sensitivities than the steeper highlands streams with piedmont streams intermediate. Model R (2) for stream-specific models was positively related to a stream's thermal sensitivity. Both the regional and the stream-specific air-water temperature regression models benefited from including mean daily discharge from regional gaging stations, but the degree of improvement declined as a stream's thermal sensitivity increased. Although catchment size had no relationship to thermal sensitivity, steeper streams or those with greater amounts of forest in their upstream watershed were less thermally sensitive. The subset of streams with three or more summers of temperature data exhibited a wide range of annual variation in thermal sensitivity at a site, with the variation not attributable to discharge, precipitation patterns, or physical attributes of streams or their watersheds. Our findings are a useful starting point to better understand patterns in stream thermal regimes. However, a more spatially and temporally comprehensive monitoring network should increase understanding of stream temperature variation and its controls as climatic patterns change.

The effect that climate change and variability will have on waterborne bacteria is a topic of increasing concern for coastal ecosystems, including the Chesapeake Bay. Surface water temperature trends in the Bay indicate a warming pattern of roughly 0.3-0.4°C per decade over the past 30 years. It is unclear what impact future warming will have on pathogens currently found in the Bay, including Vibrio spp. Using historical environmental data, combined with three different statistical models of Vibrio vulnificus probability, we explore the relationship between environmental change and predicted Vibrio vulnificus presence in the upper Chesapeake Bay. We find that the predicted response of V. vulnificus probability to high temperatures in the Bay differs systematically between models of differing structure. As existing publicly available datasets are inadequate to determine which model structure is most appropriate, the impact of climatic change on the probability of V. vulnificus presence in the Chesapeake Bay remains uncertain. This result points to the challenge of characterizing climate sensitivity of ecological systems in which data are sparse and only statistical models of ecological sensitivity exist.

Solute transport in karst aquifers is primarily constrained to relatively complex and inaccessible solution conduits where transport is often rapid, turbulent, and at times constrictive. Breakthrough curves generated from tracer tests in solution conduits are typically positively-skewed with long tails evident. Physical nonequilibrium models to fit breakthrough curves for tracer tests in solution conduits are now routinely employed. Chemical nonequilibrium processes are likely important interactions, however. In addition to partitioning between different flow domains, there may also be equilibrium and nonequilibrium partitioning between the aqueous and solid phases. A combined physical and chemical nonequilibrium (PCNE) model was developed for an instantaneous release similar to that developed by Leij and Bradford (2009) for a pulse release. The PCNE model allows for partitioning open space in solution conduits into mobile and immobile flow regions with first-order mass transfer between the two regions to represent physical nonequilibrium in the conduit. Partitioning between the aqueous and solid phases proceeds either as an equilibrium process or as a first-order process and represents chemical nonequilibrium for both the mobile and immobile regions. Application of the model to three example breakthrough curves demonstrates the applicability of the combined physical and chemical nonequilibrium model to tracer tests conducted in karst aquifers, with exceptionally good model fits to the data. The three models, each from a different state in the United States, exhibit very different velocities, dispersions, and other transport properties with most of the transport occurring via the fraction of mobile water. Fitting the model suggests the potentially important interaction of physical and chemical nonequilibrium processes., (Published by Elsevier B.V.)

Clinical feature selection problem is the task of selecting and identifying a subset of informative clinical features that are useful for promoting accurate clinical diagnosis. This is a significant task of pragmatic value in the clinical settings as each clinical test is associated with a different financial cost, diagnostic value, and risk for obtaining the measurement. Moreover, with continual introduction of new clinical features, the need to repeat the feature selection task can be very time consuming. Therefore to address this issue, we propose a novel feature selection technique for diagnosis of myocardial infarction - one of the leading causes of morbidity and mortality in many high-income countries. This method adopts the conceptual framework of biological continuum, the optimization capability of genetic algorithm for performing feature selection and the classification ability of support vector machine. Together, a network of clinical risk factors, called the biological continuum based etiological network (BCEN), was constructed. Evaluation of the proposed methods was carried out using the cardiovascular heart study (CHS) dataset. Results demonstrate a significant speedup of 4.73-fold can be achieved for the development of MI classification model. The key advantage of this methodology is the provision of a reusable (feature subset) paradigm for efficient development of up-to-date and efficacious clinical classification models., (Copyright © 2013 Elsevier Inc. All rights reserved.)

The prevalence of HIV in older adults is rising. This increase can be attributed to inconsistent condom use, low perceived disease susceptibility, and a sexual health knowledge gap found in older adults. Yet, little to no health promotion for older adults focuses on sex education. This study sought to determine the feasibility of a group-based educational program in senior housing settings and consider the utility of a self-efficacy based group education program on knowledge of disease risk and preventive techniques among older adults living in senior housing.

Many current fate and transport models based on the assumption of instantaneous sorption equilibrium of contaminants in the water column may not be valid for certain pharmaceuticals with long times to reach sorption equilibrium. In this study, a sorption kinetics model was developed and incorporated into a water quality model for the Patuxent River Estuary to evaluate the effect of sorption kinetics. Model results indicate that the assumption of instantaneous sorption equilibrium results in significant under-prediction of water column concentrations for some pharmaceuticals. The relative difference between predicted concentrations for the instantaneous versus kinetic approach is as large as 150% at upstream locations in the Patuxent Estuary. At downstream locations, where sorption processes have had sufficient time to reach equilibrium, the relative difference decreases to roughly 25%. This indicates that sorption kinetics affect a model's ability to capture accumulation of pharmaceuticals into riverbeds and the transport of pharmaceuticals in estuaries. These results offer strong evidence that chemicals are not removed from the water column as rapidly as has been assumed on the basis of equilibrium-based analyses. The findings are applicable not only for pharmaceutical compounds, but also for diverse contaminants that reach sorption equilibrium slowly., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

In many older US cities, lead (Pb) contamination of residential soil is widespread; however, contamination is not uniform. Empirically based, spatially explicit models can assist city agencies in addressing this important public health concern by identifying areas predicted to exceed public health targets for soil Pb contamination. Sampling of 61 residential properties in Baltimore City using field portable X-ray fluorescence revealed that 53 % had soil Pb that exceeded the USEPA reportable limit of 400 ppm. These data were used as the input to three different spatially explicit models: a traditional general linear model (GLM), and two machine learning techniques: classification and regression trees (CART) and Random Forests (RF). The GLM revealed that housing age, distance to road, distance to building, and the interactions between variables explained 38 % of the variation in the data. The CART model confirmed the importance of these variables, with housing age, distance to building, and distance to major road networks determining the terminal nodes of the CART model. Using the same three predictor variables, the RF model explained 42 % of the variation in the data. The overall accuracy, which is a measure of agreement between the model and an independent dataset, was 90 % for the GLM, 83 % for the CART model, and 72 % for the RF model. A range of spatially explicit models that can be adapted to changing soil Pb guidelines allows managers to select the most appropriate model based on public health targets.

Using the structural-environmental conceptual framework, this study employed mixed methods to address the question of whether sex with female sex workers contributes to HIV risk among male immigrant Latino day laborers in suburban Maryland. Because contextual factors can greatly affect HIV risk for both sex workers and their clients, this study investigated the organizational structure of sex work, factors that predicted men's hiring of sex workers, sexual behaviors performed with sex workers, and the use of condoms. Qualitative research was conducted to inform the development of a quantitative survey, but also provided crucial descriptions about the motivations, locations, arrangements, and sexual activities related to sex work. Key informant interviews (N = 10), in-depth interviews with day laborers (N = 10) and Latina female sex workers (N = 4), and two focus groups with day laborers (N = 11) were conducted, and a quantitative survey administered via Audio-enhanced Computer-assisted Self-interviewing (N = 174). Condom use was nearly universal in encounters with female sex workers, thus indicating that the sex workers were not an important source of HIV transmission in this context. Logistic regression was performed to test a model predicting sex with sex workers. Latino day laborers who reported more immigrant stress and who did not have a partner in the U.S. were more likely to have had sex with a sex worker, as were men who reported binge drinking. Structural and social conditions influenced the hiring of sex workers. Further research is warranted to better understand the interrelationships among these circumstances and to inform the development of programs to address them.

Escherichia coli is the leading indicator of microbial contamination of natural waters, and so its in-stream fate and transport needs to be understood to eventually minimize surface water contamination by microorganisms. To better understand mechanisms of E. coli release and transport from soil sediment in a creek the artificial high-water flow events were created by releasing 60-80 m(3) of city water on a tarp-covered stream bank in four equal allotments in July 2008, 2009 and 2010. A conservative tracer difluorobenzoic acid (DFBA) was added to the released water in 2009 and 2010. Water flow rate, E. coli and DFBA concentrations as well as water turbidity were monitored with automated samplers at three in-stream weirs. A one-dimensional model was applied to simulate water flow, and E. coli and DFBA transport during these experiments. The Saint-Venant equations were used to calculate water depth and discharge while a stream solute transport model accounted for release of bacteria by shear stress from bottom sediments, advection-dispersion, and exchange with transient storage (TS). Reach-specific model parameters were estimated by evaluating observed time series of flow rates and concentrations of DFBA and E. coli at all three weir stations. Observed DFBA and E. coli breakthrough curves (BTC) exhibited long tails after the water pulse and tracer peaks had passed indicating that transient storage (TS) might be an important element of the in-stream transport process. Comparison of simulated and measured E. coli concentrations indicated that significant release of E. coli continued when water flow returned to the base level after the water pulse passed and bottom shear stress was small. The mechanism of bacteria continuing release from sediment could be the erosive boundary layer exchange enhanced by changes in biofilm properties by erosion and sloughing detachment., (Published by Elsevier Ltd.)

The flux of fixed nitrogen into the marine environment is increasing as a direct result of anthropogenic nitrogen loading, but the controls on the mechanisms responsible for the removal of this increased supply are not well constrained. The fate of fixed nitrogen via mineralization and nitrogen loss processes was investigated by simulating a settling event of organic matter (OM) in mesocosms containing Chesapeake Bay sediments. Microorganisms rapidly transformed the OM during the course of a seven week incubation ultimately leading to nitrogen loss via denitrification and anaerobic ammonium oxidation (anammox). The microbial community responded quickly to the OM amendment suggesting that estuarine sediments can buffer the natural system against sudden injections of organic material. Two different levels of organic matter amendment resulted in different magnitudes of ammonium and nitrite accumulation during the incubation, but both treatments exhibited the same overall sequence of dissolved inorganic nitrogen (DIN) accumulation and removal. An inverse least-squares analysis coupled to a Michaelis-Menten prognostic model was conducted to estimate rates of nitrogen transformations from the measured DIN concentrations. Whereas the rates were higher at higher OM, the percentage of nitrogen lost via anammox was constant at 44.3 ± 0.3%. The stoichiometry of organic matter and the allochthonous supply of ammonium determined the relative contribution of anammox and denitrification to overall nitrogen loss. Further, in situ thermodynamics based on measured concentrations suggested that the energy favorability of denitrification and anammox plays a role in determining the timing of these processes as OM remineralization progresses.

Landscape-level green infrastructure creates a network of natural and semi-natural areas that protects and enhances ecosystem services, regenerative capacities, and ecological dynamism over long timeframes. It can also enhance quality of life and certain economic activity. Highways create a network for moving goods and services efficiently, enabling commerce, and improving mobility. A fundamentally profound conflict exists between transportation planning and green infrastructure planning because they both seek to create connected, functioning networks across the same landscapes and regions, but transportation networks, especially in the form of highways, fragment and disconnect green infrastructure networks. A key opportunity has emerged in the United States during the last ten years with the promotion of measures to link transportation and environmental concerns. In this article we examined the potential benefits and challenges of linking landscape-level green infrastructure planning and implementation with integrated transportation planning and highway project development in the United States policy context. This was done by establishing a conceptual model that identified logical flow lines from planning to implementation as well as the potential interconnectors between green infrastructure and highway infrastructure. We analyzed the relationship of these activities through literature review, policy analysis, and a case study of a suburban Maryland, USA landscape. We found that regionally developed and adopted green infrastructure plans can be instrumental in creating more responsive regional transportation plans and streamlining the project environmental review process while enabling better outcomes by enabling more targeted mitigation. In order for benefits to occur, however, landscape-scale green infrastructure assessments and plans must be in place before integrated transportation planning and highway project development occurs. It is in the transportation community's interests to actively facilitate green infrastructure planning because it creates a more predictable environmental review context. On the other hand, for landscape-level green infrastructure, transportation planning and development is much more established and better funded and can provide a means of supporting green infrastructure planning and implementation, thereby enhancing conservation of ecological function.

Objectives: Community hospital pediatric inpatient programs are being threatened by current financial and demographic trends. We describe a model of care and report on the financial implications associated with combining emergency department (ED) and inpatient care of pediatric patients. We determine whether this type of model could generate sufficient revenue to support physician salaries for continuous in-house coverage in community hospitals., Methods: Financial productivity and selected performance indicators were obtained from a retrospective review of registration and billing records. Data were obtained from 2 community-based pediatric hospitalist programs, which are part of a single health system and included care delivered in the ED and inpatient settings during a 1-year period from July 1, 2008, to July 1, 2009., Results: Together, the combined programs were able to generate 6079 total relative value units and collections of $244,828 annually per full-time equivalent (FTE). Salary, benefits, and practice expenses totaled $235,674 per FTE. Thus, combined daily revenues exceeded expenses and provided 104% of physician salary, benefits, and practice expenses. However, 1 program generated a net profit of $329,715 ($40,706 per FTE), whereas the other recorded a loss of $207,969 ($39,994 per FTE). Emergency department throughput times and left-without-being-seen rates at both programs were comparable to national benchmarks., Conclusions: Incorporating ED care into a pediatric hospitalist program can be an effective strategy to maintain the financial viability of pediatric services at community hospitals with low inpatient volumes that seek to provide 24-hour pediatric staffing.

A number of field experiments measuring the fluctuating intensity of a laser beam propagating along horizontal paths in the maritime environment is performed over sub-kilometer distances at the United States Naval Academy. Both above the ground and over the water links are explored. Two different detection schemes, one photographing the beam on a white board, and the other capturing the beam directly using a ccd sensor, gave consistent results. The probability density function (pdf) of the fluctuating intensity is reconstructed with the help of two theoretical models: the Gamma-Gamma and the Gamma-Laguerre, and compared with the intensity's histograms. It is found that the on-ground experimental results are in good agreement with theoretical predictions. The results obtained above the water paths lead to appreciable discrepancies, especially in the case of the Gamma-Gamma model. These discrepancies are attributed to the presence of the various scatterers along the path of the beam, such as water droplets, aerosols and other airborne particles. Our paper's main contribution is providing a methodology for computing the pdf function of the laser beam intensity in the maritime environment using field measurements.

The objective of this study was to optimize predictive modeling in the participant selection process for care management (CM) programs by determining the ideal cut point selection method. Comparisons included: (a) an evidence-based "optimal" cut point versus an "arbitrary" threshold, and (b) condition-specific cut points versus a uniform screening method. Participants comprised adult Medicaid health plan members enrolled during the entire study period (January 2007-December 2008) who had at least 1 of the chronic conditions targeted by the CM programs (n = 6459). Adjusted Clinical Groups Predictive Modeling (ACG-PM) system risk scores in 2007 were used to predict those with the top 5% highest health care expenditures in 2008. Comparisons of model performance (ie, c statistic, sensitivity, specificity, positive predictive value) and identified population size were used to assess differences among 3 cut point selection approaches: (a) single arbitrary cut point, (b) single optimal cut point, and (c) condition-specific optimal cut points. The "optimal" cut points (ie, single and condition-specific) both outperformed the "arbitrary" selection process, yielding higher probabilities of correct prediction and sensitivities. The condition-specific optimal cut point approach also exhibited better performance than applying a single optimal cut point uniformly across the entire population regardless of condition (ie, a higher c statistic, specificity, and positive predictive value, although sensitivity was lower), while identifying a more manageable number of members for CM program outreach. CM programs can optimize targeting algorithms by utilizing evidence-based cut points that incorporate condition-specific variations in risk. By efficiently targeting and intervening with future high-cost members, health care costs can be reduced.

Novel physical and chemical conditions of many modern ecosystems increasingly diverge from the environments known to have existed at any time in the history of Earth. The loss of natural land to urbanization is one of the most prevalent drivers of novel environments in freshwaters. However, current understanding of aquatic community response to urbanization is based heavily upon aggregate indicators of community structure and linear or wedge-shaped community response models that challenge ecological community theory. We applied a new analytical method, threshold indicator taxa analysis (TITAN), to a stream biomonitoring data set from Maryland to explicitly evaluate linear community response models to urbanization that implicitly assume individual taxa decline or increase at incrementally different levels of urbanization. We used TITAN (1) to identify the location and magnitude of greatest change in the frequency and abundance of individual taxa and (2) to assess synchrony in the location of change points as evidence for stream community thresholds in response to percent impervious cover in catchments. We documented clear and synchronous threshold declines of 110 of 238 macroinvertebrate taxa in response to low levels of impervious cover. Approximately 80% of the declining taxa did so between 0.5% and 2% impervious cover, whereas the last 20% declined sporadically from 2% to 25% impervious cover. Synchrony of individual responses resulted in distinct community-level thresholds ranging from < or = 0.68% (mountains), 1.28% (piedmont), and 0.96% (coastal plain) impervious cover. Upper limits (95% confidence intervals) of community thresholds were < 2% cover in all regions. Within distinct physiographic classes, higher-gradient, smaller catchments required less impervious cover than lower gradient, larger catchments to elicit community thresholds. Relatively few taxa showed positive responses to increasing impervious cover, and those that did gradually increased in frequency and abundance, approximating a linear cumulative distribution. The sharp, synchronous declines of numerous taxa established a consistent threshold response at exceptionally low levels of catchment urbanization, and uncertainty regarding the estimation of impervious cover from satellite data was mitigated by several corroborating lines of evidence. We suggest that threshold responses of communities to urban and other novel environmental gradients may be more prevalent than currently recognized.

Background: In the United States, viral respiratory infections are a leading cause of illness and hospitalization in young children. Caring for children with severe viral respiratory illness can have a substantial impact on resource utilization in the pediatric intensive care unit (PICU). The objective was to build a robust model that captures the periodicity of severe pediatric viral respiratory illness and forecasts the incidence of viral respiratory illness in the PICU., Methods: This was a retrospective time series analysis in a PICU at a quaternary care children's hospital. Patients were less than 18 years of age with laboratory-confirmed respiratory syncytial virus, influenza, parainfluenza, or adenovirus infection on or during admission from October 2002 to September 2008. Time series modeling techniques were to used to model viral incidence, using maximum likelihood estimation to identify model parameters., Results: A total of 289 patients were included in the analysis. An autoregressive model of order 10 that included an exogenous variable of community viral incidence from the previous month was able to explain and predict viral incidence in the PICU. A limitation of the study was that it included a single institution., Conclusions: The identified model, derived from historical data from both a PICU and the local community, produced accurate 1-month and 3-month forecasts of severe viral respiratory illness presentation to the PICU. These results suggest that time series models may be useful tools in forecasting the burden of severe viral respiratory illness at the institutional level, helping institutions make decisions to optimize the distribution of resources.

Background: This paper describes a multilevel youth violence prevention effort called SAFER Latinos (Seguridad, Apoyo, Familia, Educacion, y Recursos), a collaboration between The George Washington University School of Public Health and Health Services (GWU) and two key Latino community organizations., Objectives: To implement and evaluate an intervention addressing factors within the social ecology of an immigrant Latino community., Methods: The intervention includes (1) Social promotores for family outreach and problem resolution; (2) Youth peer advocates at the high school level; (3) a drop-in center with support services for families and youth; and (4) community events, capacity building, and messages. Evaluation includes a baseline and follow-up surveys (N = 1,400) and focus groups., Lessons Learned: (1) Community circumstances change, requiring regular program adaptation. (2) Community interventions with research face potential contradictions in purpose impacting management of the collaboration and model fidelity. (3) Etiological models tied to interventions may have to be revisited owing to changes in the character and dynamics of the immigrant community.

Vibrio cholerae, the causative agent of cholera, is a naturally occurring inhabitant of the Chesapeake Bay and serves as a predictor for other clinically important vibrios, including Vibrio parahaemolyticus and Vibrio vulnificus. A system was constructed to predict the likelihood of the presence of V. cholerae in surface waters of the Chesapeake Bay, with the goal to provide forecasts of the occurrence of this and related pathogenic Vibrio spp. Prediction was achieved by driving an available multivariate empirical habitat model estimating the probability of V. cholerae within a range of temperatures and salinities in the Bay, with hydrodynamically generated predictions of ambient temperature and salinity. The experimental predictions provided both an improved understanding of the in situ variability of V. cholerae, including identification of potential hotspots of occurrence, and usefulness as an early warning system. With further development of the system, prediction of the probability of the occurrence of related pathogenic vibrios in the Chesapeake Bay, notably V. parahaemolyticus and V. vulnificus, will be possible, as well as its transport to any geographical location where sufficient relevant data are available.

Purpose: Making choices about everyday activities is a normal event for many adults. However, when an adult moves into an assisted living (AL) community, making choices becomes complicated by perceived needs and community practices. This study examines the relationship between choice and need in the context of practices, using medication administration practices as the case in point., Design and Methods: A 5-year ethnographic study collected information from 6 AL settings in Maryland. Ethnographic interviews (n = 323) and field notes comprise the data described in this article., Results: AL organizations used practice rationales based on state regulations, professional responsibility, safety concerns, and social model values to describe and explain their setting-specific practices. The result was varying levels of congruence between the setting's practices and individual resident's needs and choices. That is, in some cases, the resident's needs were lost to the organization's practices, and in other cases, organizations adapted to resident need and choices. These findings suggest that individuals and organizations adapt to each other, resulting in practices that are not bound by state requirement or other practice rationales., Implications: AL residences vary due to both internal and external forces, not just the public policies that define them. State regulations need to be responsive to both the needs and the choices of individual residents and to the people who work in an AL.

In this article we present a framework for assessing climate change impacts on water and watershed systems to support management decision-making. The framework addresses three issues complicating assessments of climate change impacts--linkages across spatial scales, linkages across temporal scales, and linkages across scientific and management disciplines. A major theme underlying the framework is that, due to current limitations in modeling capabilities, assessing and responding to climate change should be approached from the perspective of risk assessment and management rather than as a prediction problem. The framework is based generally on ecological risk assessment and similar approaches. A second theme underlying the framework is the need for close collaboration among climate scientists, scientists interested in assessing impacts, and resource managers and decision makers. A case study illustrating an application of the framework is also presented that provides a specific, practical example of how the framework was used to assess the impacts of climate change on water quality in a mid-Atlantic, U.S., watershed.

Background: Recent studies indicate that the composition of fine particulate matter [PM

Based on the thrombolytic predictive instrument (TPI), we sought to create electrocardiographically based, real-time decision support to immediate identification of patients with ST-segment elevation myocardial infarction (STEMI) likely to benefit from primary percutaneous coronary intervention (PCI) compared with thrombolysis. Using data from the Atlantic Cardiovascular Patient Outcomes Research Team (C-PORT) Trial, we tested a mathematical model predicting mortality in patients with STEMI if treated with PCI and if treated with thrombolytic therapy. We adapted the model for incorporation into computerized electrocardiograms as a PCI-TPI. For patients with STEMI in the C-PORT Trial, the model yielded unbiased mortality predictions: for those receiving thrombolysis, it predicted 6.3% mortality and actual mortality was 6.0% (95% confidence interval 3.0 to 10.6); for those receiving PCI, it predicted 4.5% mortality and actual mortality was 3.9% (95% confidence interval 1.4 to 8.2). Excellent discrimination was reflected by its receiver operating characteristic curve area of 0.86. According to the model, and validated by actual trial outcomes, 1/3 of subjects accounted for all the mortality benefit from PCI. In conclusion, for STEMI, the PCI-TPI accurately predicts mortality for treatment with PCI and with thrombolytic therapy. Incorporated into electrocardiogram, it may assist targeting PCI to those who benefit most and identifying patients before hospitalization for whom a receiving hospital should prepare for PCI.

The earlier experimental papers in this series dealt with replication of our DeltapH = +1 IIED (intention imprinted electrical device) experiment carried out in Minnesota. This work was replicated at 3-IIED sites and 7 control sites in the United States and Europe that demonstrated room temperature information entanglement between the macroscopic sized ( approximately 10(3) to 10(4) cubic feet volume) IIED sites and non-IIED-sites (control sites) over distances separated by up to 5000 to 6000 miles. During these studies, we discovered how to gain a quantitative measure of the elevation of the thermodynamic free energy per unit volume, deltaG*(H)+, above our normal U(1) electromagnetic gauge symmetry state, for the aqueous H(+) ion in these " conditioned" spaces. In simpler language, what this means is that one can now continuously monitor a complementary and alternative medicine (CAM) office space, research space, or clinic space to gain a continuous record of (1) How much the space has been elevated or depleted in thermodynamic free energy, relative to our normal physical reality, by the processes occurring there; (2) how much the biofields of the practitioners and patients are perturbing the collective subtle energy field of these spaces; and (3) the monitoring of specific IIEDs imprinted for aiding the healing process of patients with specific pathologies under study or treatment. It allows CAM practitioners to investigate and utilize "information medicined", to evaluate the subtle energy component of various psychotronic devices, and to evaluate the efficacy of various subtle energy potentization processes for various supplements, remedies, and other materials. This paper contributes several key things to this growing body of work: (1) it develops a quantitative theoretical picture for the determination of deltaG*(H)+ from pH measurements in partially "conditioned"spaces; (2) it provides experimental, deltaG*(H)+ data for all 10 sites of the overall experimental system, (3) it provides deltaG*(H)+ data for measurements carried out in small CAM facilities and at a 1-week-long healing workshop facility; and (4) it illustrates a potential biofeedback tool to assist both individual humans and coherently coupled groups of humans to significantly enhance their evolutionary progress to Adept, Master, and perhaps even Avatar levels of performance in the world.

An estimation of the nonpoint sources of fecal coliform (FC) has been formulated as an inverse parameter estimation problem, using FC observation data from the receiving waters. An inverse algorithm was integrated into the three-dimensional transport model, HEM-3D. The modified Gauss-Newton method was used for the optimal estimation of the loads. The approach is straightforward and requires less effort in modification of the existing hydrodynamic model. Model experiments were conducted to investigate the feasibility of load estimation in a tidal river. The parameter uncertainty and accuracy associated with load estimation are discussed using data sets with different sampling sizes. The inverse model was applied to the tidal Wye River, Maryland, USA, to estimate FC nonpoint sources and to develop an allowable load for the river to attain water quality standards. The model results suggest that the inverse modeling approach is suitable for estimating FC nonpoint sources. The inverse method not only provides an efficient approach to assess the contribution of nonpoint sources, but has the additional advantage of addressing the problems of the uncertainty and error associated with FC simulation in the estuary using hydrodynamic models.

Aims: Little is known about the heterogeneity in and risk factors associated with trajectories of smoking during adolescence. This study aimed to (1) identify smoking trajectories empirically and (2) identify risk factors for trajectory group membership., Design: Latent growth mixture models were used to identify population smoking trajectories, and logistic regression was used to estimate risk factors for group membership., Setting: The participants were drawn from seven middle schools in a Maryland school district., Participants: Participants consisted of 1320 6th graders who were followed to the 9th grade., Measurements: Measurements of smoking risk factors were made in the fall of 6th grade and smoking stage was assessed on five different occasions between the fall of 6th and 9th grades., Findings: Five distinct smoking trajectories were identified. Overall, being female, having friends who smoked, deviance acceptance and outcome expectations were associated with an increased likelihood of being an intender, delayed escalator, early experimenter and early user compared to a never smoker. Additionally, comparisons with never smokers revealed unique identifiers for intenders, early experimenters and early users, but not delayed escalators., Conclusions: There is much heterogeneity in the manner in which middle-schoolers progress from having no intention of smoking to becoming smokers. Implications for prevention programs are discussed.

The environmental fate of herbicides in estuaries is poorly understood. Estuarine physical transport processes and the episodic nature of herbicide release into surface waters complicate interpretation of water concentration measurements and allocation of sources. Water concentrations of herbicides and two triazine degradation products (CIAT [6-amino-2-chloro-4-isopropylamino-s-triazine] and CEAT [6-amino-2-chloro-4-ethylamino-s-triazine]) were measured in surface water from four sites on 40 d from 4 Apr. through 29 July 19% in the Patuxent River estuary, part of the Chesapeake Bay system. Atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine) was most persistent and present in the highest concentrations (maximum = 1.29 microg/L). Metolachlor [2-chloro-6'-ethyl-N-(2-methoxy-1-methylethyl)-o-acetoluidide], CIAT, CEAT, and simazine (1-chloro-3,5-bisethylamino-2,4,6-triazine) were frequently detected with maximum concentration values of 0.61, 1.1, 0.76, and 0.49 microg/L, respectively. A physical transport model was used to interpret atrazine concentrations in the context of estuarine water transport, giving estimates of in situ degradation rates and total transport. The estimated half-life of atrazine in the turbid, shallow upper estuary was t(1/2) = 20 d, but was much longer (t(1/2) = 100 d) in the deeper lower estuary. Although most (93%) atrazine entered the estuary upstream via the river, simulations suggested additional inputs directly to the lower estuary. The total atrazine load to the estuary from 5 April to 15 July was 71 kg with 48% loss by degradation and 31% exported to the Chesapeake Bay. Atrazine persistence in the estuary is directly related to river flows into the estuary. Low flows will increase atrazine residence time in the upper estuary and increase degradation losses.

The U.S. Geological Survey has developed a methodology for statistically relating nutrient sources and land-surface characteristics to nutrient loads of streams. The methodology is referred to as SPAtially Referenced Regressions On Watershed attributes (SPARROW), and relates measured stream nutrient loads to nutrient sources using nonlinear statistical regression models. A spatially detailed digital hydrologic network of stream reaches, stream-reach characteristics such as mean streamflow, water velocity, reach length, and travel time, and their associated watersheds supports the regression models. This network serves as the primary framework for spatially referencing potential nutrient source information such as atmospheric deposition, septic systems, point-sources, land use, land cover, and agricultural sources and land-surface characteristics such as land use, land cover, average-annual precipitation and temperature, slope, and soil permeability. In the Chesapeake Bay watershed that covers parts of Delaware, Maryland, Pennsylvania, New York, Virginia, West Virginia, and Washington D.C., SPARROW was used to generate models estimating loads of total nitrogen and total phosphorus representing 1987 and 1992 land-surface conditions. The 1987 models used a hydrologic network derived from an enhanced version of the U.S. Environmental Protection Agency's digital River Reach File, and course resolution Digital Elevation Models (DEMs). A new hydrologic network was created to support the 1992 models by generating stream reaches representing surface-water pathways defined by flow direction and flow accumulation algorithms from higher resolution DEMs. On a reach-by-reach basis, stream reach characteristics essential to the modeling were transferred to the newly generated pathways or reaches from the enhanced River Reach File used to support the 1987 models. To complete the new network, watersheds for each reach were generated using the direction of surface-water flow derived from the DEMs. This network improves upon existing digital stream data by increasing the level of spatial detail and providing consistency between the reach locations and topography. The hydrologic network also aids in illustrating the spatial patterns of predicted nutrient loads and sources contributed locally to each stream, and the percentages of nutrient load that reach Chesapeake Bay.

In 1997, Maryland had no available ambient Federal Reference Method data on particulate matter less than 2.5 microm in aerodynamic diameter (PM23), but did have annual ambient data for PM smaller than 10 microm (PM10) at 24 sites. The PM10 data were analyzed in conjunction with local annual and seasonal zip-code-level emission inventories and with speciated PM2.5 data from four nearby monitors in the IMPROVE network (located in the national parks, wildlife refuges, and wilderness areas) in an effort to estimate annual average and seasonal high PM2.5 concentrations at the 24 PM10 monitor sites operating from 1992 to 1996. All seasonal high concentrations were estimated to be below the 24-hr PM2.5 National Ambient Air Quality Standards (NAAQS) at the sites operating in Maryland between 1992 and 1996. The estimates also indicated that 12 monitor sites might exceed the 3-year annual average PM2.5 NAAQS of 15 microg/m3, but Maryland's air quality shows signs that it has been improving since 1992. The estimates also were compared with actual measurements after the PM2.5 monitor network was installed. The estimates were adequate for describing the chemical composition of the PM2.5, forecasting compliance status with the 24-hr and annual standards, and determining the spatial variations in PM2.5 across central Maryland.

Atmospheric deposition of nitrate nitrogen and ammonium nitrogen has been identified as a major factor in the decline of water quality in the Chesapeake Bay. Reports have indicated that atmospheric deposition may account for 25 to 80% of the total nitrogen load entering the bay. However, uncertainties exist regarding the accuracy of the atmospheric deposition inputs, nitrogen retention coefficients, and in-stream nutrient uptake rates used in these studies. This project was designed to reassess the potential inputs of atmospheric nitrogen deposition to the bay through the use of a high-resolution wet deposition model, improved wet and dry deposition and nutrient retention estimates, existing soils and land use data, and geographic information systems software. Model results indicate that the methods used in previous studies may overestimate the contribution of atmospheric nitrate and ammonium deposition to the Chesapeake Bay watershed (CBW). Wet and dry atmospheric nitrate and ammonium nitrogen deposition estimates to the CBW ranged from 52.7 to 141.9 and 41.9 to 60.1 million kg/yr, respectively, between 1984 and 1996. Dry and total atmospheric deposition loads to the watershed are substantially less than previous estimates. Estimates of the percent contribution of atmospherically deposited nitrogen to the Chesapeake Bay represent between 20 and 32% of the total nitrate and ammonium nitrogen load to the watershed from all nitrogen sources. While these estimates are lower than many other published estimates, regression analysis of model parameters, nitrogen retention coefficients, output, and measured in-stream nitrogen loads indicate that the calculated nitrogen loads may still be too high.

Small, inexpensive, often poorly made handguns known as "Saturday night specials" are disproportionately involved in crime. Maryland banned the sale of Saturday night specials effective January 1, 1990. During the 2 years between the law's passage in 1988 and its effective date, legal handgun sales in Maryland were 34% higher than expected (p = 0.09). Interrupted time-series analysis of age-adjusted homicide rates for 1975-1998 with statistical controls for trends in two neighboring states, social and economic variables, and temporal patterns in Maryland's homicide rates was used to assess the effect of the law. Estimates of the Saturday night special ban effects depended on the assumption made about the timing of the law's effects. Models that assumed a delayed or gradual effect of the Saturday night special ban produced estimates indicating that firearm homicide rates were 6.8-11.5% lower than would have been expected without the Saturday night special ban (p < or =0.05). The model that assumed an immediate, constant change in response to the law showed no law effect, unless an outlier was excluded from the analysis. Excluding this outlier, the model estimated a 15% increase in firearm homicides associated with the Saturday night special ban. None of the models revealed significant law effects on nonfirearm homicides.

In 1990 Congress mandated that all state Medicaid programs implement both retrospective and prospective drug-use review (DUR). Nearly a decade later, implementation of prospective DUR (ProDUR) remains incomplete, and few of the implemented systems have been rigorously evaluated. This study was undertaken to analyze the impact of ProDUR screening of beta-agonist inhaler use in the Maryland Medicaid program from 1994 through 1996. The study used a pre/postcomparison series cohort design with data from Maryland, Georgia, and Iowa. Regression analysis was used to control for population differences between states in the year before the ProDUR intervention. The analysis used Medicaid and Medicare enrollment and claims data to select the study cohorts, assess exposure to the ProDUR intervention, develop patient risk profiles, and tabulate rates of adverse clinical outcomes for each subject. The study compared incidence rates for adverse outcomes for 2 1/2 years after implementation of the beta-agonist screens in Maryland, Georgia, and Iowa. Descriptive time plots and regression models were used to test the hypothesis that ProDUR screening reduces the incidence of adverse effects associated with misuse of beta-agonist inhalers. The study end points included 10 clinical outcomes related to therapeutic duplication and drug-drug interactions involving beta-agonist inhaler use by elderly individuals with chronic lung disease. No significant changes in the incidence of these outcomes could be linked to ProDur screening.

Catastrophe models, which describe and predict discontinuous changes in system state variables, were used to model the exposure to blood and bodily fluids and more conventional occupational accidents among 1708 health care workers. Workers at three hospitals completed a survey measuring HIV-relevant exposures (needlesticks, cuts, splashes, contact with open wounds), the accident rate for broadly-defined injuries, and several occupationally relevant themes: safety climate, shift work, depression symptoms, work pace, verbal abuse, and professional group membership. A cusp (cubic polynomial) model predicting HIV-relevant exposures specifically was more accurate (R2 = 0.56) than a comparable linear model containing the same variables (R2 = 0.07). Some of the foregoing variables predisposed workers to greater differences in HIV-relevant and general accident exposures: shiftwork, climate, depressive symptoms, and work pace. Other variables governed how close an individual was to a critical threshold where a harmful incident would take place: verbal abuse, professional group membership. Similarly, a cusp model for accident incidents predicted from HIV-relevant exposures and occupational variables was also more accurate (R2 = 0.75) than comparison models. Two variables predisposed the worker to a greater accident risk: depression symptoms and shift work. Four other variables predisposed the worker to lesser accident risk: job satisfaction, safety climate, environmental stressors, and work pace. Compliance with the universal precautions and HIV-related training were not relevant to either of the models.

This study tested the equivalence of a theoretical model of parenting behaviors linking financial strain to adolescents' achievement for African American and European American families and for single- and two-parent families. The sample included an economic cross-section of African American (n = 387) and European American families (n = 230) from single- (n = 171) and two-parent (n = 446) homes. Multi-group analyses revealed no significant differences in the structural equation models between the African American and European American families, or between the single- and two-parent families. Results demonstrated that negative parent-adolescent relationships and parental school involvement mediated the relation between financial strain and adolescents' academic achievement.

Using a theoretical model of access, factors associated with rural adolescents' willingness to use primary care services through a school-based health center (SBHC) were examined. Standardized measures of health status and use were administered to 633 adolescents in grades 7-12 who resided in one rural western Maryland county. Although only 6.5% (n = 41) of the sample indicated a willingness to change their regular source of care to an SBHC, greater numbers of adolescents reported a willingness to use SBHC services, with 18%, 38%, 25%, and 16%, indicating interest in routine, acute medical, miscellaneous, and reproductive health care services, respectively. Logistic regression analysis found those adolescents who reported eligibility for free-reduced lunch and no regular source of care for illness were 3.3 and 5.4 times more likely, respectively, to use an SBHC as a primary care site than those unwilling to change their source of care. Data suggest that initially many rural adolescents appear unwilling to change their primary care site to an SBHC, but do express a willingness to use offered services.

Traditionally, most nursing staff development departments are either decentralized or centralized. This article presents the advantages and disadvantages of each of these organizational systems and describes a model used at the National Institutes of Health that combines elements of both. Strategies to control for the disadvantages are outlined. This organizational structure may enable staff development educators to better meet the educational needs of nurses in today's health care settings.

Two unique models for caring for the uninsured and underinsured are operating in Maryland. The first is a group practice, primary care model with a unique ambulatory Medicare waiver that has had a positive impact on patients and physicians. The second is a financial model--an all-payer prospective rate-setting system for all critical care inpatient hospitals that, during a 13-year period from 1977 through 1989, has saved the citizens of the state approximately $5.361 billion, has allowed hospitals to provide $1.657 billion of charity care and bad debts, and has earned $517 million in net profits. The reasons for the success of each of the models are discussed and form the basis for a practical and politically feasible proposal: merge the best aspects of each model into an ambulatory primary care-based model financed through an all-payer prospective charge system.

This paper presents a model for an interdisciplinary discharge planning team, with emphasis on functional status and improved coordination and continuity among providers, along with a description of the design and implementation of such a program in a university hospital. Results show that more patients are discussed and served, with more emphasis on the functional ability of patients, in an interdisciplinary versus traditional setting. Communication and education between house staff and team members increased substantially with this approach.

Not only are advances being made in delaying the virulent course of human immunodeficiency virus (HIV), but preventive measures are now available to eliminate or delay opportunistic infections related to HIV. Changes in the treatment of HIV-related diseases have shifted the focus from inpatient to community care. However, questions exist whether these gains in treatment outcomes will be available to all persons with HIV infection and whether uniform standards of care will be established and maintained among health care providers. In Maryland, and automated AIDS information system, HIVIS, consisting of administrative data bases and medical records systems, is used to measure health and social services costs and utilization and to assess their accessibility, quality and effectiveness. Since these data bases are available in other states, HIVIS serves as a model which may be implemented elsewhere for AIDS and other diseases.

This paper estimates a multidisciplinary team approach to the treatment of anorexia nervosa. Beginning with a review of the demographic characteristics of seventy-five patients involved in this sample, a brief examination of diagnostic and etiological issues, and a description of treatment practices, the authors describe a five-year inpatient experience involving a team composed of social work, medicine and nursing. The importance of each role in treating this disorder is discussed and initial outcome data are reviewed. The social worker's responsibilities, experiences, and interventions with the families of patients are emphasized. Several general principles used in working with anorectic families derived from this five-year experience are also described.