A Playroom Internal Waiting Area Improves Productivity in the Pediatric Emergency Department

Introduction: Pediatric emergency department (PED) volume is often constrained by the number of available treatment rooms. In many PEDs patients occupy treatment rooms while awaiting test results or imaging, thereby delaying care for patients who arrive after them.Methods: We opened a PED where selected patients were moved to a playroom when they did not actively require a treatment room. The treatment room was then available for the next patient. We measured the effect of using the playroom on time from arrival to rooming and length of stay (LOS) using proportional hazards regression and the odds of being roomed within 30 minutes of arrival using logistic regression. We adjusted for the number  of the previous eight patients who were “playroom eligible”; age; triage category; provider; the number of patients who arrived within the preceding hour; prior census; and testing ordered in the preceding eight patients.Results: We analyzed 43,634 patient encounters, of which 10,134 (23%) were playroom eligible. The adjusted hazards ratio for the next patient being roomed was 1.14 (95% confidence interval [CI], 1.10-1.18) per prior playroom eligible patient. The adjusted odds ratio of the next patient being roomed within 30 minutes was 1.46 (95% CI, 1.33-1.56) per prior playroom eligible patient. The playroom typically decreased median rooming time by four to 42 minutes and LOS by two to 40 minutes depending on patient volumes and acuity. The benefit of the playroom was maximal at busier times.Conclusion: Implementing a playroom in the PED for selected patients generally decreased time to rooming of the next patient and LOS

Networked engineering notebooks for smart manufacturing

A goal of the industrial internet is to make information about manufacturing processes and resources available wherever decision making may be required. Agile use of information is a cornerstone of data analytics, but analytical methods more generally, including model-based investigations of manufacturability and operations, do not so easily benefit from this data. Rather than relating anonymous patterns of data to outcomes, these latter analytical methods are distinguished as relying on conceptual or physics-based models of the real world. Such models require careful consideration of the fitness of the data to the purpose of the analysis. Verification of these analyses, then, is a significant bottleneck. A related problem, that of ascertaining reproducible results in scientific claims, is being addressed through executable notebook technology. This paper proposes to use notebook technologies to address that bottleneck. It describes how this notebook technology, linked to internet-addressable ontologies and analytical metamodels, can be used to make model-based analytical methods more verifiable, and thus more effective for manufacturers

Production system identification with genetic programming

Modern system-identification methodologies use artificial neural nets, integer linear programming, genetic algorithms, and swarm intelligence to discover system models. Pairing genetic programming, a variation of genetic algorithms, with Petri nets seems to offer an attractive, alternative means to discover system behaviour and structure. Yet to date, very little work has examined this pairing of technologies. Petri nets provide a grey-box model of the system, which is useful for verifying system behaviour and interpreting the meaning of operational data. Genetic programming promises a simple yet robust tool to search the space of candidate systems. Genetic programming is inherently highly parallel. This paper describes early experiences with genetic programming of Petri nets to discover the best interpretation of operational data. The systems studied are serial production lines with buffers

Dynamic production system identification for smart manufacturing systems

This paper presents a methodology, called production system identification, to produce a model of a manufacturing system from logs of the system's operation. The model produced is intended to aid in making production scheduling decisions. Production system identification is similar to machine-learning methods of process mining in that they both use logs of operations. However, process mining falls short of addressing important requirements; process mining does not (1) account for infrequent exceptional events that may provide insight into system capabilities and reliability, (2) offer means to validate the model relative to an understanding of causes, and (3) updated the model as the situation on the production floor changes. The paper describes a genetic programming (GP) methodology that uses Petri nets, probabilistic neural nets, and a causal model of production system dynamics to address these shortcomings. A coloured Petri net formalism appropriate to GP is developed and used to interpret the log. Interpreted logs provide a relation between Petri net states and exceptional system states that can be learned by means of novel formulation of probabilistic neural nets (PNNs). A generalized stochastic Petri net and the PNNs are used to validate the GP-generated solutions. The methodology is evaluated with an example based on an automotive assembly system

Successional Change in Phosphorus Stoichiometry Explains the Inverse Relationship between Herbivory and Lupin Density on Mount St. Helens

The average nitrogen-to-phosphorus ratio (N?P) of insect herbivores is less than that of leaves, suggesting that P may mediate plant-insect interactions more often than appreciated. We investigated whether succession-related heterogeneity in N and P stoichiometry influences herbivore performance on N-fixing lupin (Lupinus lepidus) colonizing primary successional volcanic surfaces, where the abundances of several specialist lepidopteran herbivores are inversely related to lupin density and are known to alter lupin colonization dynamics. We examined larval performance in response to leaf nutritional characteristics using gelechiid and pyralid leaf-tiers, and a noctuid leaf-cutter.Apple JL, Wink M, Wills SE, Bishop JG (2009) Successional Change in Phosphorus Stoichiometry Explains the Inverse Relationship between Herbivory and Lupin Density on Mount St. Helens. PLoS ONE 4(11): e7807. doi:10.1371/journal.pone.000780

Development Resilience Estimation: Theory and Applications

The past five to ten years has seen the emergence of a new term on the humanitarian and development economics landscapes, resilience. While this term holds considerable promise, international development practitioners and the academic community have yet to reach consensus on a consistent definition of resilience and few, if any, theory-based methods for estimating resilience in a development context have been developed. This dissertation introduces an econometric strategy for estimating individual or household-level development resilience from panel data and applies this strategy to two different contexts. The first, more theoretical, paper proposes a conditional moments-based approach to development resilience estimation and illustrates the method empirically using household panel data from pastoralist communities in northern Kenya. The results demonstrate not only the method and its potential as a targeting tool for resilience-building interventions, but also help explain the behavioral paradox of apparent herd overstocking in pastoral communities. The second paper of the dissertation applies the development resilience approach to evaluate the impact of an index insurance product on resilience. Taking advantage of an experimental, multi-round, household panel dataset, the paper employs an instrumental variable approach to evaluate the impact of an index-based livestock insurance product in Northern Kenya on development resilience in terms of both household herd size, the primary productive asset in the region, and child health. The results indicate that index-based livestock insurance increases household resilience to drought in terms of household livestock holdings. Insurance is also associated will substantially higher nutritional resilience in the children of drought-affected households. The final paper of the dissertation evaluates the empirical relationship between livelihood diversification—both on-farm crop diversification and income diversification—and well-being, measured as monthly household expenditures per adult equivalent, in rural Uganda. Results indicate that income diversification is negatively associated with resilience. Crop diversification is associated with increased resilience, but only when considering poverty thresholds above the rural absolute poverty line. Diversification into cash crops and non-farm income does not increase resilience. These results indicate that crop diversification (although not diversification into cash crops) should be considered in similar contexts as a tool for increasing resilience, although not necessarily for the poorest households. More generally, it demonstrates the importance of applying a development resilience approach when evaluating the potential benefits of risk management strategies and resilience-building activities

A Playroom Internal Waiting Area Improves Productivity in the Pediatric Emergency Department

Introduction: Pediatric emergency department (PED) volume is often constrained by the number of available treatment rooms. In many PEDs patients occupy treatment rooms while awaiting test results or imaging, thereby delaying care for patients who arrive after them.Methods: We opened a PED where selected patients were moved to a playroom when they did not actively require a treatment room. The treatment room was then available for the next patient. We measured the effect of using the playroom on time from arrival to rooming and length of stay (LOS) using proportional hazards regression and the odds of being roomed within 30 minutes of arrival using logistic regression. We adjusted for the number  of the previous eight patients who were “playroom eligible”; age; triage category; provider; the number of patients who arrived within the preceding hour; prior census; and testing ordered in the preceding eight patients.Results: We analyzed 43,634 patient encounters, of which 10,134 (23%) were playroom eligible. The adjusted hazards ratio for the next patient being roomed was 1.14 (95% confidence interval [CI], 1.10-1.18) per prior playroom eligible patient. The adjusted odds ratio of the next patient being roomed within 30 minutes was 1.46 (95% CI, 1.33-1.56) per prior playroom eligible patient. The playroom typically decreased median rooming time by four to 42 minutes and LOS by two to 40 minutes depending on patient volumes and acuity. The benefit of the playroom was maximal at busier times.Conclusion: Implementing a playroom in the PED for selected patients generally decreased time to rooming of the next patient and LOS

Resilience Measurement: A Moment-Based Approach to Resilience Identification and Aggregation

The international community has recently been focused on the importance of building resilience to avoid repeated humanitarian disasters and improve the sustainability of development outcomes. Despite this consensus, there is little agreement on how best to measure resilience at the microeconomic level. The goal of this paper is to develop an empirical strategy for estimating individual or household level resilience based on theoretical work by Barrett & Constas. The moments-based approach allows us to estimate stochastic and possibly nonlinear well-being dynamics, with obvious benefits over linear models in contexts where poverty traps may be found. We then develop a decomposable resilience measure based on the Foster, Greer, & Thorbecke class of poverty measures, giving us the ability to compare the resilience of various sub-populations of interest. We finish with an empirical example of resilience measurement using household panel data from Northern Kenya where we find there are strong path dynamics in resilience, both in terms of dietary diversity and livestock holdings. Resilience is negatively impacted by drought and also strongly correlated with several household-level characteristics

Prevalence and Mechanisms of Broad-Spectrum β-Lactam Resistance in Enterobacteriaceae: a Children's Hospital Experience▿

The objective of this study was to investigate the trends and patterns of resistance in β-lactamase-producing members of the family Enterobacteriaceae in a children's hospital over a 9-year period (1999 to 2007). Clinically significant isolates of the Enterobacteriaceae were screened for patterns of broad-spectrum resistance to β-lactams. The strains likely to be resistant were subsequently confirmed by an inhibitor-based disc test. The plasmid-mediated resistance determinants in these isolates were identified by PCR and by in vitro transformation, which successfully reproduced the AmpC phenotype unrestricted by the species of the host organisms. Among 8,048 Enterobacteriaceae isolates belonging to the four chromosomal ampC-negative or -nonfunctional genera, 86 (1.07%) isolates (56 Escherichia coli isolates, 22 Klebsiella species isolates, 1 Proteus mirabilis isolate, and 7 Salmonella species isolates) exhibited broad-spectrum β-lactam resistance patterns. These organisms collectively produced three classes of β-lactamases, including class A extended-spectrum β-lactamases (n = 47), class C or AmpC β-lactamases (n = 36, including 4 isolates that produced both class A and class C enzymes), and class A or B carbapenem-hydrolyzing β-lactamases (n = 3). The proportion increased from 0.46% during the first 3 years to 1.84% during the last 3 years (relative risk [RR], 4.04; 95% confidence interval [CI], 2.28 to 7.42; P < 0.001). The increase was mainly due to the emergence of a plasmid-mediated blaCMY-2 β-lactamase, the incidence of which increased from 0.11% during the first 3 years to 0.96% during the last 3 years (RR, 9.11; 95% CI, 2.76 to 30.1; P = 0.001). Class A-type resistance increased slightly during the study period, from 0.35% during the first 3 years to 0.85% during the last 3 years (RR, 2.42; 95% CI, 1.15 to 5.07; P = 0.02). A Proteus mirabilis strain was documented to possess a novel blaDHA determinant. Of special concern, three carbapenemase-producing isolates were identified between 2003 and 2006. The infections caused by resistant isolates of the Enterobacteriaceae mainly affected hospitalized patients with underlying conditions; however, 19 (22%) episodes were of community onset in otherwise well children. The rate of resistance to broad-spectrum β-lactams among isolates of the Enterobacteriaceae is increasing in children in both hospital- and community-acquired settings, and the resistance is driven largely by plasmid-mediated AmpC β-lactamases. These data have important implications for empirical antimicrobial strategies targeting serious pediatric infections. Further study of this problem is warranted