Rugged landscapes: Complexity and implementation science

BACKGROUND: Mis-implementation-defined as failure to successfully implement and continue evidence-based programs-is widespread in public health practice. Yet the causes of this phenomenon are poorly understood. METHODS: We develop an agent-based computational model to explore how complexity hinders effective implementation. The model is adapted from the evolutionary biology literature and incorporates three distinct complexities faced in public health practice: dimensionality, ruggedness, and context-specificity. Agents in the model attempt to solve problems using one of three approaches-Plan-Do-Study-Act (PDSA), evidence-based interventions (EBIs), and evidence-based decision-making (EBDM). RESULTS: The model demonstrates that the most effective approach to implementation and quality improvement depends on the underlying nature of the problem. Rugged problems are best approached with a combination of PDSA and EBI. Context-specific problems are best approached with EBDM. CONCLUSIONS: The model\u27s results emphasize the importance of adapting one\u27s approach to the characteristics of the problem at hand. Evidence-based decision-making (EBDM), which combines evidence from multiple independent sources with on-the-ground local knowledge, is a particularly potent strategy for implementation and quality improvement

RITUAL, TIME, AND ENTERNITY

It is argued here that the construction of time and eternity are among ritual's entailments. In dividing continuous duration into distinct periods ritual distinguishes two temporal conditions: (1) that prevailing in mundane periods and (2) that prevailing during the intervals between them. Differences in the frequency, length, and relationship among the rituals constituting different liturgical orders are considered, as are differences between mundane periods and ritual's intervals with respect to social relations, cognitive modes, meaningfulness, and typical interactive frequencies. Periods, it is observed, relate to intervals as everchanging to never-changing, and close relationships of never changing to eternity, eternity to sanctity, and sanctity to truth are proposed. In the argument that ritual's “times out of time” really are outside mundane time, similarities to the operations of digital computers and Herbert Simon's discussion of interaction frequencies in the organization of matter are noted.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72989/1/j.1467-9744.1992.tb00996.x.pd

Nested inversion polymorphisms predispose chromosome 22q11.2 to meiotic rearrangements [RETRACTED]

Inversion polymorphisms between low-copy repeats (LCRs) might predispose chromosomes to meiotic non-allelic homologous recombination (NAHR) events and thus lead to genomic disorders. However, for the 22q11.2 deletion syndrome (22q11.2DS), the most common genomic disorder, no such inversions have been uncovered as of yet. Using fiber-FISH, we demonstrate that parents transmitting the de novo 3 Mb LCR22A–D 22q11.2 deletion, the reciprocal duplication, and the smaller 1.5 Mb LCR22A–B 22q11.2 deletion carry inversions of LCR22B–D or LCR22C–D. Hence, the inversions predispose chromosome 22q11.2 to meiotic rearrangements and increase the individual risk for transmitting rearrangements. Interestingly, the inversions are nested or flanking rather than coinciding with the deletion or duplication sizes. This finding raises the possibility that inversions are a prerequisite not only for 22q11.2 rearrangements but also for all NAHR-mediated genomic disorders

Genetic contributors to risk of schizophrenia in the presence of a 22q11.2 deletion

Schizophrenia occurs in about one in four individuals with 22q11.2 deletion syndrome (22q11.2DS). The aim of this International Brain and Behavior 22q11.2DS Consortium (IBBC) study was to identify genetic factors that contribute to schizophrenia, in addition to the ~20-fold increased risk conveyed by the 22q11.2 deletion. Using whole-genome sequencing data from 519 unrelated individuals with 22q11.2DS, we conducted genome-wide comparisons of common and rare variants between those with schizophrenia and those with no psychotic disorder at age ≥25 years. Available microarray data enabled direct comparison of polygenic risk for schizophrenia between 22q11.2DS and independent population samples with no 22q11.2 deletion, with and without schizophrenia (total n = 35,182). Polygenic risk for schizophrenia within 22q11.2DS was significantly greater for those with schizophrenia (padj = 6.73 × 10−6). Novel reciprocal case–control comparisons between the 22q11.2DS and population-based cohorts showed that polygenic risk score was significantly greater in individuals with psychotic illness, regardless of the presence of the 22q11.2 deletion. Within the 22q11.2DS cohort, results of gene-set analyses showed some support for rare variants affecting synaptic genes. No common or rare variants within the 22q11.2 deletion region were significantly associated with schizophrenia. These findings suggest that in addition to the deletion conferring a greatly increased risk to schizophrenia, the risk is higher when the 22q11.2 deletion and common polygenic risk factors that contribute to schizophrenia in the general population are both present

Replication Data for: Stacked Regression and Poststratification

These files contain all of the replication data and code for "Stacked Regression and Poststratification" (forthcoming at Political Analysis), by Joseph T. Ornstein

A model of food reward learning with dynamic reward exposure

The process of conditioning via reward learning is highly relevant to the study of food choice and obesity. Learning is itself shaped by environmental exposure, with the potential for such exposures to vary substantially across individuals and across place and time. In this paper, we use computational techniques to extend a well-validated standard model of reward learning, introducing both substantial heterogeneity and dynamic reward exposures. We then apply the extended model to a food choice context. The model produces a variety of individual behaviors and population-level patterns which are not evident from the traditional formulation, but which offer potential insights for understanding food reward learning and obesity. These include a lock-in effect, through which early exposure can strongly shape later reward valuation. We discuss potential implications of our results for the study and prevention of obesity, for the reward learning field, and for future experimental and computational work

LOCAL BENEFIT-SEEKING IN THE LEGISLATURE: AN INVESTIGATION OF CONGRESSIONAL STAFFING DECISIONS

In prior work, I proposed a prisoner's dilemma theory for the partisan pattern that political ticket splitting has taken in the United States: where Republicans, since 1932, have done consistently better in races for the White House than in contests for Congressional seats. The theory relies on the key assumption that Democratic legislative representatives are more willing to engage in local benefit-seeking. By examining the personal staffing decisions made by members of the House this paper provides some empirical support for such an assumption. Relative to their Republican counterparts, Democratic legislators both hire more personal staff and allocate a higher percentage of the staff hired to district rather than Washington offices. Copyright 1991 Blackwell Publishers Ltd..