The epidemic character of community-associated methicillin-resistant Staphylococcus aureus, especially the geographically widespread clone USA300, is poorly understood. USA300 isolates carry a type ...IV staphylococcal chromosomal cassette mec (SCCmec) element conferringβ-lactam antibiotic class resistance and a putative pathogenicity island, arginine catabolic mobile element (ACME). Physical linkage between SCCmec and ACME suggests that selection for antibiotic resistance and for pathogenicity may be interconnected. We constructed isogenic mutants containing deletions of SCCmec and ACME in a USA300 clinical isolate to determine the role played by these elements in a rabbit model of bacteremia. We found that deletion of type IV SCCmec did not affect competitive fitness, whereas deletion of ACME significantly attenuated the pathogenicity or fitness of USA300. These data are consistent with a model in which ACME enhances growth and survival of USA300, allowing for genetic “hitchhiking” of SCCmec. SCCmec in turn protects against exposure toβ-lactams.
Do democracies perform better than more autocratic political systems? Most existing literature focuses on single issues, such as maintaining the peace, avoiding famines, or promoting stable economic ...growth. The key to policy success for all these and other issues is adaptive policymaking in complex, dynamic environments. Relying on theory and empirical tests from policy process studies, we focus on extreme policy punctuations as indicators of maladaptive policymaking. We conceive of a continuum from the most open democracies to the most closed authoritarian systems, with intermediate forms of less open democracies, hybrid regimes, and less closed authoritarian systems. Based on a review of the existing literature, we extract four factors that seem to affect maladaptive and hence more punctuated policymaking: friction imposed by formal rules and informal norms on the policymaking process, the absence of incentives to address problems, centralization in policymaking, and lack of diversity in channels of information. Many of these factors cluster, so it is difficult to discern their specific effects, but our approach allows a start at doing so.
Processes to introduce carboxylic acid functional groups onto surfaces have been widely applied in various applications, such as molecular grafting for biosensors, biocompatibility improvement, gas ...filter/adsorption in environmental engineering and the enhancement of interfacial adhesion between fillers (such as carbon or glass fibre) and matrices (such as epoxy resin) in composite materials. To develop an environmental-friendly process to introduce a stable and high concentration of carboxylic acid functional groups, Acrylic Acid (AAc) was deposited onto silicon wafers using remote argon atmospheric plasma processing (APP) and vapour phase grafting in a bespoke Pyrex cylindrical chamber. The chamber stands vertically with an APP nozzle installed at the top, a sample platform downstream and an AAc vapour inlet on the chamber wall. In this way, both the effect of atmospheric gas on the process and AAc monomer fragmentation during APP can be limited. Silicon specimens were exposed to a combination of plasma gas and AAc vapour. Surface wettability was evaluated by measurement of water contact angles and chemical composition was analyzed using X-ray Photoelectron Spectroscopy (XPS). The peak at the binding energy of 289.2eV, which fits with COOH components in the C1s spectrum of poly-AAc, was used to determine the contribution of the carboxylic acid groups depositing on the surface because it was absent in the C1s peak of untreated silicon wafers. A more stable and hydrophilic wettability and the binding energy peak at 289.2eV from XPS show the presence of carboxylic acid groups on the surface of samples treated with AAc vapour with the remote argon-APP. A higher intensity peak at 289.2eV was detected, compared with the surfaces activated by a conventional argon-APP in which the AAc vapour is exposed to the plasma glow, suggesting a potential, rapid and novel remote APP process for carboxylic acid functional group deposition.
•A more stable and hydrophilic surface can be achieved with the remote argon-atmospheric pressure plasma (APP) treatment with acrylic acid (AAc) vapour.•A strong intensity peak at 289.2 eV (presence of carboxylic acid groups) was detected (27.6%), compared with the surfaces activated by a conventional APP (10.8%), in which the plasma is in direct in contact with the AAc precursor, and the theoretical atomic ratio for AAc (33.3%).•A potential, rapid and novel remote APP technique for the retention of a high concentration carboxylic acid functional groups in the deposit.
Recent studies have reported blood levels of polybrominated diphenyl ethers (PBDEs) in the U.S. population. Information about neonatal levels and about the relationship to polychlorinated biphenyls ...(PCBs) exposures is limited. /// The objective was to characterize levels and determinants of fetal exposure to PBDEs and PCBs among newborns from Baltimore, Maryland. /// We analyzed umbilical cord blood for eight PBDEs and 35 PCBs from infants delivered at the Johns Hopkins Hospital. Maternal and infant characteristics were abstracted from medical records. /// Ninety-four percent of cord serum samples had quantifiable levels of at least one PBDE congener, and > 99% had at least one detectable PCB congener. PBDE concentrations in cord blood were similar to those reported in other studies from North America. Strong correlations were observed within but not across PCB and PBDE classes. Multivariate models showed that many factors independently predicted exposure to BDE-47, BDE-100, and BDE-153 and CB-118, CB-138/158, CB-153, and CB-180. Generally, infants of Asian mothers had lower PBDE and PCB levels, and infants of smokers had higher levels. Increased maternal body mass index was associated with lower levels of PCBs but not PBDEs. Levels of PCBs but not PBDEs were lower in births from married and multiparous mothers. Increased maternal age was associated with higher PCB levels but lower PBDE levels. /// Although many of the factors we investigated were independent predictors of both PBDE and PCB levels, in some cases the direction of associations was different. More research is needed to better understand the sources and pathways of PBDE exposure.
We explored the associations of dual sensory impairment (DSI) with long-term depressive and anxiety symptoms as well as low perceived social support (LPSS) as a modifier of these associations.
...Multinomial logistic regression models were used to examine the associations of DSI and single sensory impairment (hearing pure-tone average > 25 dB and vision impaired visual acuity and/or contrast sensitivity) with long-term depressive symptom (≥8 on the 10-item Center for Epidemiologic Studies-Depression Scale) and anxiety symptom (present on the Hopkins Symptom Checklist) latent classes from group-based trajectory models (rare/never; mild/moderate increasing; chronically high) among 2102 Health, Aging and Body Composition Study participants (mean age:74.0 ± 2.8 years; 51.9 % female) over 10 years. Models were adjusted by demographic characteristics and cardiovascular risk factors, and LPSS. An additional model evaluated the two-way interaction between DSI and LPSS.
DSI was associated with increased risk of being chronically depressed (Risk Ratio, RR = 1.99, 95 % Confidence Interval, CI: 1.25, 3.17), not mild/moderate increasingly depressed (RR = 1.25, 95 % CI: 0.91, 1.71). DSI had increased risk of being mild/moderate increasingly anxious (RR = 1.60, 95 % CI: 1.16, 2.19) and chronically anxious (RR = 1.86, 95 % CI: 1.05, 3.27) groups, as compared to no impairments. Hearing impairment was associated with being mild/moderate increasingly anxious (RR = 1.34, 95 % CI: 1.01, 1.79). No other associations were found for single sensory impairments. LPSS did not modify associations.
Sensory measures were time-fixed, and LPSS, depression and anxiety measures were self-reported.
Future research is warranted to determine if DSI therapies may lessen long-term chronically high depressive and anxiety symptoms.
•Dual sensory impairment (DSI) is associated with chronic depressive symptoms.•DSI is associated with mild/moderate increasingly and chronically anxiety.•Hearing impairment is associated with anxiety symptoms.•Low social support does not modify long-term associations.
Selection of a modeling approach is an important step in the conservation planning process, but little guidance is available. We compared two statistical and three theoretical habitat modeling ...approaches representing those currently being used for avian conservation planning at landscape and regional scales: hierarchical spatial count (HSC), classification and regression tree (CRT), habitat suitability index (HSI), forest structure database (FS), and habitat association database (HA). We focused our comparison on models for five priority forest-breeding species in the Central Hardwoods Bird Conservation Region: Acadian Flycatcher, Cerulean Warbler, Prairie Warbler, Red-headed Woodpecker, and Worm-eating Warbler. Lacking complete knowledge on the distribution and abundance of each species with which we could illuminate differences between approaches and provide strong grounds for recommending one approach over another, we used two approaches to compare models: rank correlations among model outputs and comparison of spatial correspondence. In general, rank correlations were significantly positive among models for each species, indicating general agreement among the models. Worm-eating Warblers had the highest pairwise correlations, all of which were significant (
P
< 0.05). Red-headed Woodpeckers had the lowest agreement among models, suggesting greater uncertainty in the relative conservation value of areas within the region. We assessed model uncertainty by mapping the spatial congruence in priorities (i.e., top ranks) resulting from each model for each species and calculating the coefficient of variation across model ranks for each location. This allowed identification of areas more likely to be good targets of conservation effort for a species, those areas that were least likely, and those in between where uncertainty is higher and thus conservation action incorporates more risk. Based on our results, models developed independently for the same purpose (conservation planning for a particular species in a particular geography) yield different answers and thus different conservation strategies. We assert that using only one habitat model (even if validated) as the foundation of a conservation plan is risky. Using multiple models (i.e., ensemble prediction) can reduce uncertainty and increase efficacy of conservation action when models corroborate one another and increase understanding of the system when they do not.
Purpose The purpose of this study was to evaluate whether participation in a commercially available board review course affected the likelihood of passing the general surgery certifying exam (CE) of ...the American Board of Surgery (ABS). Methods Candidates who took the ABS CE during the 2012–2013 academic year were surveyed electronically about their participation in commercial board review courses on the ABS website immediately before receiving their exam results. The primary outcome variable was passing the CE. Results were adjusted for background variables shown to correlate with CE pass rates using multilevel logistic regression. Results Of the 1,386 candidates who took the CE and had sufficient data for analysis, 974 of 1,064 first-time examinees (92%) and 272 of 322 repeat examinees (84%) completed the survey. Nearly 78% of survey respondents took a review course. Repeat examinees (85%) were more likely to attend a review course than first-time examinees (76%, P = .002). There were no significant differences in CE pass rates for first-time or repeat examinees who took a review course compared with those who did not (83.7% vs 80.7% for first-time examinees and 77.8% vs 69.0% for repeat examinees, P = .32 and P = .24, respectively). First-time examinee nonrespondents did not differ in their CE pass rates from those who responded to the survey ( P = .113); however, repeat examinee nonrespondents had lesser CE pass rates than survey responders ( P = .009). None of the review courses included had CE pass rates that differed significantly from the others after we controlled for program characteristics, ABS qualifying exam scores, medical school, and sex of the examinees. Conclusion This study used a large, prospectively collected national sample with a high response rate to study the effect of board review courses on CE performance on the ABS examination. On the basis of this survey, there was no evidence that participating in a board review course provided a benefit to passing the CE of the ABS. These results should be considered when preparation for the CE is undertaken.
We examine regularities and differences in public budgeting in comparative perspective. Budgets quantify collective political decisions made in response to incoming information, the preferences of ...decision makers, and the institutions that structure how decisions are made. We first establish that the distribution of budget changes in many Western democracies follows a non-Gaussian distribution, the power function. This implies that budgets are highly incremental, yet occasionally are punctuated by large changes. This pattern holds regardless of the type of political system—parliamentary or presidential—and for level of government. By studying the power function's exponents we find systematic differences for budgetary increases versus decreases (the former are more punctuated) in most systems, and for levels of government (local governments are less punctuated). Finally, we show that differences among countries in the coefficients of the general budget law correspond to differences in formal institutional structures. While the general form of the law is probably dictated by the fundamental operations of human and organizational information processing, differences in the magnitudes of the law's basic parameters are country- and institution-specific.
OBJECTIVES:Surgery residency serves 2 purposes—prepare graduates for general surgery (GS) practice or postresidency surgical fellowship, leading to specialty surgical practice (SS). This study was ...undertaken to elucidate factors influencing career choice for these 2 groups.
METHODS:All US allopathic surgery residency graduates from 2009 to 2013 (n = 5512) were surveyed by the American Board of Surgery regarding confidence, autonomy, and reasons for career selection between GS and SS. Surveys were distributed by mail in November 2013, with follow-up mailings to initial nonrespondents.
RESULTS:Sixty-one percent (3354) of graduates completed the survey; 26% pursued GS, and 74% SS. GS expressed greater levels of confidence than SS across the common surgical procedures queried. Confidence increased with each year after completion of residency for GS but not SS. The decision to pursue GS or SS was made during residency by 77% and 74%, respectively. Fifty-seven percent of those who chose GS indicated that a GS mentor significantly influenced their decision. GS rated procedural variety, opportunity for practice autonomy, choice of practice location, and influence of a mentor as reasons to pursue GS practice. SS listed control over scope of practice, prestige, salary, and specialty interest as reasons to pursue SF. Both groups expressed a high degree of satisfaction with their career choice (GS, 94%; SS, 90%).
CONCLUSIONS:Most graduates who pursue GS practice are confident and content. The decision to pursue GS is strongly influenced by a GS mentor. Lack of confidence may be a more significant factor for choosing SS. These findings suggest opportunities for improvements in confidence and mentorship during residency.
A Model of Choice for Public Policy Jones, Bryan D.; Baumgartner, Frank R.
Journal of public administration research and theory,
07/2005, Letnik:
15, Številka:
3
Journal Article
Recenzirano
Odprti dostop
Punctuated equilibrium is supposed to be a viable alternative to incrementalism, and, indeed, the authors of the model have sometimes made such claims. But punctuated equilibrium was developed to ...explain change in policy subsystems and does not serve as a complete model of policy choice in the same way that incrementalism has served. This article develops a full-blown and viable model of choice for public policy based on disproportionate information processing. Its dynamics are based in the allocation of political attention to policy topics and the manner in which political systems process information. The model leads directly to outcomes that are consistent with punctuated equilibrium and are not generally consistent with incrementalism. Incrementalism, however, may be deduced from the model as a special case. The model is best tested using stochastic process approaches. Incrementalism logically must yield a normal distribution of outcomes, but disproportionate information processing yields leptokurtic outcomes. Adding institutional constraints only makes the stochastic process implications more severe. To support our arguments, we present both static and dynamic simulations of these processes. We also show that these simulations are consistent with observations of U.S. government budgets.
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