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Objectives: Rates of cognitive, academic and behavioral comorbidities are elevated in children with epilepsy. The contribution of environmental and genetic influences to comorbidity risk is not fully understood. This study investigated children with epilepsy, their unaffected siblings, and controls to determine the presence and extent of risk associated with family relatedness across a range of epilepsy comorbidities. Methods: Participants were 346 children (8–18 years), n=180 with recent-onset epilepsy, their unaffected siblings (n=67), and healthy first-degree cousin controls (n=99). Assessments included: (1) Child Behavior Checklist/6-18 (CBCL), (2) Behavior Rating Inventory of Executive Function (BRIEF), (3) history of education and academic services, and (4) lifetime attention deficit hyperactivity disorder (ADHD) diagnosis. Analyses consisted of linear mixed effect models for continuous variables, and logistic mixed models for binary variables. Results: Differences were detected between the three groups of children across all measures (p<.001). For ADHD, academic problems, and executive dysfunction, children with epilepsy exhibited significantly more problems than unaffected siblings and controls; siblings and controls did not differ statistically significantly from each other. For social competence, children with epilepsy and their unaffected siblings displayed more abnormality compared with controls, with no statistically significant difference between children with epilepsy and unaffected siblings. For behavioral problems, children with epilepsy had more abnormality than siblings and controls, but unaffected siblings also exhibited more abnormalities than controls. Conclusions: The contribution of epilepsy and family relatedness varies across specific neurobehavioral comorbidities. Family relatedness was not significantly associated with rates of ADHD, academic problems and executive dysfunction, but was associated with competence and behavioral problems. (JINS, 2018, 24, 1–9)
Burn patients are particularly vulnerable to infection, and an estimated half of all burn deaths are due to infections. This study explored risk factors for healthcare-associated infections (HAIs) in adult burn patients.
Retrospective cohort study.
Tertiary-care burn center.
Adults (≥18 years old) admitted with burn injury for at least 2 days between 2004 and 2013.
HAIs were determined in real-time by infection preventionists using Centers for Disease Control and Prevention criteria. Multivariable Cox proportional hazards regression was used to estimate the direct effect of each risk factor on time to HAI, with inverse probability of censor weights to address potentially informative censoring. Effect measure modification by burn size was also assessed.
Overall, 4,426 patients met inclusion criteria, and 349 (7.9%) patients had at least 1 HAI within 60 days of admission. Compared to <5% total body surface area (TBSA), patients with 5%–10% TBSA were almost 3 times as likely to acquire an HAI (hazard ratio [HR], 2.92; 95% CI, 1.63–5.23); patients with 10%–20% TBSA were >6 times as likely to acquire an HAI (HR, 6.38; 95% CI, 3.64–11.17); and patients with >20% TBSA were >10 times as likely to acquire an HAI (HR, 10.33; 95% CI, 5.74–18.60). Patients with inhalational injury were 1.5 times as likely to acquire an HAI (HR, 1.61; 95% CI, 1.17–2.22). The effect of inhalational injury (P=.09) appeared to be larger among patients with ≤20% TBSA.
Larger burns and inhalational injury were associated with increased incidence of HAIs. Future research should use these risk factors to identify potential interventions.
There has been a marked decline in the summer extent of Arctic sea ice over the past few decades. Data from autonomous ice mass-balance buoys can enhance our understanding of this decline. These buoys monitor changes in snow deposition and ablation, ice growth, and ice surface and bottom melt. Results from the summer of 2008 showed considerable large-scale spatial variability in the amount of surface and bottom melt. Small amounts of melting were observed north of Greenland, while melting in the southern Beaufort Sea was quite large. Comparison of net solar heat input to the ice and heat required for surface ablation showed only modest correlation. However, there was a strong correlation between solar heat input to the ocean and bottom melting. As the ice concentration in the Beaufort Sea region decreased, there was an increase in solar heat to the ocean and an increase in bottom melting.
To develop avalanche runout models for short slopes, field measurements were made at 48 short-slope avalanche paths located in the Coast, Columbia and Rocky Mountains of western Canada, and at several paths in eastern Canada. Field studies included detailed topographic surveys and estimation of the extreme runout position in each path. A statistical runout model was developed using the runout ratio method, for which runout ratios from the four mountain ranges are well fit by an extreme-value type I (Gumbel) distribution when the β point is defined at the uppermost point where the slope is 24°. A second model was developed by regressing the α angle for the extreme runout position on numerous terrain variables. This regression model uses three predictor variables that can be easily measured in the field or on topographic maps. Length-scale effects were noted in both models, but are more pronounced in the runout ratio model. A comparison of models developed using the two methods shows that the runout ratio model estimates more conservative (longer) runout distances than the regression model for most threshold probabilities. Data from 13 additional paths from Switzerland and Québec, Canada, are used to test the models.
Ventilator-associated pneumonia (VAP) is a frequent complication of severe burn injury. Comparing the current ventilator-associated event-possible VAP definition to the pre-2013 VAP definition, we identified considerably fewer VAP cases in our burn ICU. The new definition does not capture many VAP cases that would have been reported using the pre-2013 definition.
Climate change is occurring. Deviations from historic temperatures and precipitation plus increased frequency of extreme events are modifying agriculture systems globally. Adapting agricultural management practices offers a way to lessen the effects or exploit opportunities. Herein many aspects of the adaptation issue are discussed, including needs, strategies, observed actions, benefits, economic analysis approaches, role of public/private actors, limits, and project evaluation. We comment on the benefits and shortcomings of analytical methods and suggested economic efforts. Economists need to play a role in such diverse matters as projecting adaptation needs, designing adaptation incentives, and evaluating projects to ensure efficiency and effectiveness.
Of all the different methods employed to estimate the mean absolute magnitude of RR Lyrae variables, only an analysis of the Baade-Wesselink type can determine this quantity directly. The distance to a globular cluster can therefore be measured by determining <MV>RR for that cluster instead of being forced to assume that <MV>RR is the same as that of the nearby field variables. This is important in that the field stars may have a different luminosity than cluster variables. In addition, since <MV>RR should depend on the composition (especially helium) and history of mass loss of these stars, this quantity may vary from cluster to cluster.
The radio galaxy B1610–605 within the Abell cluster A3627 has a low-brightness tail extending at least 26 arcmin from the nucleus of the 14 · 5m galaxy. The structure of this tail has been explored using observations with the Molonglo Observatory Synthesis Telescope (MOST) and the Australia Telescope Compact Array (ATCA). We present details of the brightness, width and alignment of the tail. The single tail expands and brightens rapidly within 2 arcmin of the nucleus. Confinement by the pressure of the cluster medium maintains a low but constant brightness for the tail between 10 and 25 arcmin. There are indications of turbulence down the tail but the position of the ridge remains within 1 · 6 arcmin of the initial alignment throughout its length.
Using optical and infrared photometry and echelle spectroscopy of variable V8 in the globular cluster M5, we derive a cluster distance of 6.8 kpc using the Baade-Wesselink method. This agrees with the prediction obtained for the cluster’s metallicity using a sample of 19 field stars studied by us and by Liu and Janes (this volume). It also agrees well with estimates for Mv obtained from statistical parallaxes of field stars. It agrees as well with the main sequence fitting procedure where we have used only HD 103095, the field halo dwarf with the most accurate trigonometric parallax (3% error), and which has a metallicity almost identical to that of M5. The star is also cool, hence unevolved, and is not a binary. Using the luminosity of the cluster’s main sequence, both Yale and Victoria isochrones yield a cluster age of 18 ± 3 Gyrs.
In recent years several authors have questioned the reality of a widely accepted and apparently large increase in marine biodiversity through the Cenozoic. Here we use collection-level occurrence data from the rich and uniquely well documented New Zealand (NZ) shelfal marine mollusc fauna to test this question at a regional scale. Because the NZ data were generated by a small number of workers and have been databased over many decades, we have been able to either avoid or quantify many of the biases inherent in analyses of past biodiversity. In particular, our major conclusions are robust to several potential taphonomic and systematic biases and methodological uncertainties, namely non-uniform loss of aragonitic faunas, biostratigraphic range errors, taxonomic errors, choice of time bins, choice of analytical protocols, and taxonomic rank of analysis.
The number of taxa sampled increases through the Cenozoic. Once diversity estimates are standardized for sampling biases, however, we see no evidence for an increase in marine mollusc diversity in the NZ region through the middle and late Cenozoic. Instead, diversity has been approximately constant for much of the past 40 Myr and, at the species and genus levels, has declined over the past ~5 Myr. Assuming that the result for NZ shelfal molluscs is representative of other taxonomic groups and other temperate faunal provinces, then this suggests that the postulated global increase in diversity is either an artifact of sampling bias or analytical methods, resulted from increasing provinciality, or was driven by large increases in diversity in tropical regions. We see no evidence for a species-area effect on diversity. Likewise, we are unable to demonstrate a relationship between marine temperature and diversity, although this question should be re-examined once refined shallow marine temperature estimates become available.
Cenozoic sediments of Florida contain one of the most highly fossiliferous sequences of extinct sirenians in the world. Sirenians first occur in Florida during the Eocene (ca. 40 Ma), have their peak diversity during the late Oligocene–Miocene (including the widespread dugongid Metaxytherium), and become virtually extinct by the late Miocene (ca. 8 Ma). Thereafter during the Pliocene and Pleistocene, sirenians are represented in Florida by abundant remains of fossil manatees (Trichechus sp.). Stable isotopic analyses were performed on 100 teeth of fossil sirenians and extant Trichechus manatus from Florida in order to reconstruct diets (as determined from δ13C values) and habitat preferences (as determined from δ18O values) and test previous hypotheses based on morphological characters and associated floral and faunal remains. A small sample (n = 6) of extant Dugong dugon from Australia was also analyzed as an extant model to interpret the ecology of fossil dugongs.
A pilot study of captive manatees and their known diet revealed an isotopic enrichment (ɛ∗) in δ13C of 14.0‰, indistinguishable from previously reported ɛ∗ for extant medium to large terrestrial mammalian herbivores with known diets. The variation in δ18OV-SMOW reported here is interpreted to indicate habitat preferences, with depleted tooth enamel values (≈25‰) representing freshwater rivers and springs, whereas enriched values (≈30‰) indicate coastal marine environments. Taken together, the Eocene to late Miocene sirenians (Protosirenidae and Dugongidae) differ significantly in both δ13C and δ18O from Pleistocene and Recent manatees (Trichechidae). In general, Protosiren and the fossil dugongs from Florida have carbon isotopic values that are relatively positive (mean δ13C = −0.9‰) ranging from −4.8‰ to 5.6‰, interpreted to represent a specialized diet of predominantly seagrasses. The oxygen isotopic values (mean δ18O = 29.2‰) are likewise relatively positive, indicating a principally marine habitat preference. These interpretations correlate well with previous hypotheses based on morphology (e.g., degree of rostral deflection) and the known ecology of modern Dugong dugon from the Pacific Ocean. In contrast, the fossil and extant Trichechus teeth from Florida have relatively lower carbon isotopic values (mean δ13C = −7.2‰) that range from −18.2‰ to 1.7‰, interpreted as a more generalized diet ranging from C3 plants to seagrasses. The relatively lower oxygen isotopic values (mean δ18O = 28.1 ‰) are interpreted as a more diverse array of freshwater and marine habitat preferences than that of Protosiren and fossil dugongs. This study of Cenozoic sirenians from Florida further demonstrates that stable isotopes can test hypotheses previously based on morphology and associated floral and faunal remains. All these data sets taken together result in a more insightful approach to reconstructing the paleobiology of this interesting group of ancient aquatic mammalian herbivores.
The dynamic model Nitrogen Dynamics in Crop rotations in Ecological Agriculture (NDICEA) was used to assess the nitrogen (N), phosphorus (P) and potassium (K) balance of long-term organic cropping trials and typical organic crop rotations on a range of soil types and rainfall zones in the UK. The measurements of soil N taken at each of the organic trial sites were also used to assess the performance of NDICEA. The modeled outputs compared well to recorded soil N levels, with relatively small error margins. NDICEA therefore seems to be a useful tool for UK organic farmers. The modeling of typical organic rotations has shown that positive N balances can be achieved, although negative N balances can occur under high rainfall conditions and on lighter soil types as a result of leaching. The analysis and modeling also showed that some organic cropping systems rely on imported sources of P and K to maintain an adequate balance and large deficits of both nutrients are apparent in stockless systems. Although the K deficits could be addressed through the buffering capacity of minerals, the amount available for crop uptake will depend on the type and amount of minerals present, current cropping and fertilization practices and the climatic environment. A P deficit represents a more fundamental problem for the maintenance of crop yields and the organic sector currently relies on mined sources of P which represents a fundamental conflict with the International Federation of Organic Agriculture Movements organic principles.
The proboscidean Gomphotherium is reported here from the Alajuela Formation of Panama. Gomphotherium was widespread throughout Holarctica during the Miocene, and the Panama fossil represents the extreme southernmost occurrence of this genus in the New World. Allocation of the Panama Gomphotherium to a valid species is impossible given both the fragmentary material represented and the taxonomic complexity of species assigned to this genus. In North America, Gomphotherium has a relatively long biochronological range from the middle Miocene (~15 Ma) to early Pliocene (~5 Ma). Based on morphological comparisons, the Panama Gomphotherium is either middle Miocene, thus representing the earliest-known entry of this genus into Central America, or late Miocene/early Pliocene, which challenges the currently accepted middle Miocene age of the Alajuela Formation as it has been previously reported from Panama.
Healthcare-associated methicillin-resistant Staphylococcus aureus (MRSA) infections are a major cause of morbidity, mortality, and cost among hospitalized patients. Little is known about their impact on post-discharge resource utilization. The purpose of this study was to estimate post-discharge healthcare costs and utilization attributable to positive MRSA cultures during a hospitalization.
Our study cohort consisted of patients with an inpatient admission lasting longer than 48 hours within the US Department of Veterans Affairs (VA) system between October 1, 2007, and November 30, 2010. Of these patients, we identified those with a positive MRSA culture from microbiology reports in the VA electronic medical record. We used propensity score matching and multivariable regression models to assess the impact of positive culture on post-discharge outpatient, inpatient, and pharmacy costs and utilization in the 365 days following discharge.
Our full cohort included 369,743 inpatients, of whom, 3,599 (1.0%) had positive MRSA cultures. Our final analysis sample included 3,592 matched patients with and without positive cultures. We found that, in the 12 months following hospital discharge, having a positive culture resulted in increases in post-discharge pharmacy costs ($776, P<.0001) and inpatient costs ($12,167, P<.0001). Likewise, having a positive culture increased the risk of a readmission (odds ratio [OR]=1.396, P<.0001), the number of prescriptions (incidence rate ratio [IRR], 1.138; P<.0001) and the number of inpatient days (IRR, 1.204; P<.0001,) but decreased the number of subsequent outpatient encounters (IRR, 0.941; P<.008).
The results of this study indicate that MRSA infections are associated with higher levels of post-discharge healthcare cost and utilization. These findings indicate that financial benefits resulting from infection prevention efforts may extend beyond the initial hospital stay.