Abstract
A density functional theory (DFT) approach to computing transition metal oxide heat of formation without adjustable parameters is presented. Different degrees of
d
-electron localization in ...oxides are treated within the DFT+
U
approach with site-dependent, first-principles Hubbard
U
-parameters obtained from linear response theory, and delocalized states in the metallic phases are treated without Hubbard corrections. Comparison of relative stabilities of these differently treated phases is enabled by a local
d
-electron density matrix-dependent model, which was found by genetic programming against experimental reference formation enthalpies. This mathematically simple model does not explicitly depend on the Hubbard-corrected ionic species and is shown to reproduce the heats of formation of the Mott insulators Ca
2
RuO
4
and Y
2
Ru
2
O
7
within ∼3% of experimental results, where the experimental training data did not contain Ru oxides. This newly developed method thus absolves from the need for element-specific corrections fitted to experiments in existing Hubbard-corrected approaches to the prediction of reaction energies of transition metal oxides and metals. The absence of fitting parameters opens up here the possibility to predict relative thermodynamic stabilities and reaction energies involving
d
-states of varying degree of localization at transition metal oxide interfaces and defects, where site-dependent
U
-parameters will be particularly important and devising a fitting scheme against experimental data with predictive power would be exceedingly difficult.
Approximate entropy (AE) has been proposed as a measure of anesthetic drug effect in electroencephalographic data. Recently, a new method called permutation entropy (PE) based on symbolic dynamics ...was also proposed to measure the complexity in an electroencephalographic series. In this study, the AE and PE were applied to electroencephalographic recordings for revealing the effect of sevoflurane on brain activity. The dose-response relation of PE during sevoflurane anesthesia was compared with that of AE.
Nineteen patients' electroencephalographic data were collected during the induction of general anesthesia with sevoflurane. PE and AE were applied to the electroencephalographic recordings, and the performance of both measures was assessed by pharmacokinetic-pharmacodynamic modeling and prediction probability. To ensure an accurate complexity measure of electroencephalographic recordings, a wavelet-based preprocessor was built in advance.
Both PE and AE could distinguish between the awake and anesthetized states and were highly correlated to each other (r = 0.8, P = 0.004). The pharmacokinetic-pharmacodynamic model adequately described the dose-response relation between PE and AE and sevoflurane effect site concentration. The coefficient R between PE and effect site concentration was 0.89 +/- 0.07 for all patients, compared with 0.60 +/- 0.14 for AE. Prediction probabilities of 0.86 +/- 0.04 and 0.79 +/- 0.09 for PE and AE showed that PE has a stronger ability to differentiate between the awake and anesthetic states.
The results show that PE can estimate the sevoflurane drug effect more effectively than AE. This method could be applied to design a new electroencephalographic monitoring system to estimate sevoflurane anesthetic drug effect.
The macrogeographic distribution of obesity in the United States, including the association between elevation and body mass index (BMI), is largely unexplained. This study examines the relationship ...between obesity and elevation, ambient temperature and urbanization.
Data from a cross-sectional, nationally representative sample of 422603 US adults containing BMI, behavioral (diet, physical activity, smoking) and demographic (age, sex, race/ethnicity, education, employment, income) variables from the 2011 Behavioral Risk Factor Surveillance System were merged with elevation and temperature data from WorldClim and with urbanization data from the US Department of Agriculture. There was an approximately parabolic relationship between mean annual temperature and obesity, with maximum prevalence in counties with average temperatures near 18 °C. Urbanization and obesity prevalence exhibited an inverse relationship (30.9% in rural or nonmetro counties, 29.2% in metro counties with <250000 people, 28.1% in counties with population from 250000 to 1 million and 26.2% in counties with >1 million). After controlling for urbanization, temperature category and behavioral and demographic factors, male and female Americans living <500 m above sea level had 5.1 (95% confidence interval (CI) 2.7-9.5) and 3.9 (95% CI 1.6-9.3) times the odds of obesity, respectively, as compared with counterparts living ≥ 3000 m above sea level.
Obesity prevalence in the United States is inversely associated with elevation and urbanization, after adjusting for temperature, diet, physical activity, smoking and demographic factors.
Pharmaceutical and agrochemical discovery programs are under considerable pressure to meet increasing global demand and thus require constant innovation. Classical hydrocarbon scaffolds have long ...assisted in bringing new molecules to the market place, but an obvious omission is that of the Platonic solid cubane. Eaton, however, suggested that this molecule has the potential to act as a benzene bioisostere. Herein, we report the validation of Eaton's hypothesis with cubane derivatives of five molecules that are used clinically or as agrochemicals. Two cubane analogues showed increased bioactivity compared to their benzene counterparts whereas two further analogues displayed equal bioactivity, and the fifth one demonstrated only partial efficacy. Ramifications from this study are best realized by reflecting on the number of bioactive molecules that contain a benzene ring. Substitution with the cubane scaffold where possible could revitalize these systems, and thus expedite much needed lead candidate identification.
Over 25 years ago, Eaton proposed that cubane could act as a benzene bioisostere. This hypothesis has now been confirmed with the synthesis and evaluation of cubane derivatives of five biologically important molecules: Two cubane analogues showed increased bioactivity compared to their benzene counterparts whereas two further analogues were of equal bioactivity.
Successful management of spatially isolated coral reefs is contingent on an understanding of ecological connections across populations. To investigate genetic connectivity of the depth-generalist ...coral species
Montastraea cavernosa
, populations from both shallow (15–30 m) and mesophotic coral ecosystems (30–70 m) in the Gulf of Mexico (GOM) were analyzed with microsatellite genotyping. A series of upstream and downstream sites were chosen in marine protected areas including Carrie Bow Cay, Belize; Flower Garden Banks and nearby mesophotic bank habitats; Pulley Ridge; and Dry Tortugas. Patterns of genetic diversity within the northwest GOM supported relatively open coral populations with high levels of gene flow between shallow and mesophotic depth zones, consistent with strong oceanographic patterns and hypothesized availability of coral reef habitats in the GOM. Conversely, genetic differentiation within Belize and the southeast GOM indicate relative isolation of shallow and mesophotic
M. cavernosa
populations in these regions. Structure analysis showed dominant genetic clusters within each region that did not correlate strongly with depth zones, and identified a cluster of unknown origin contributing to high differentiation at Pulley Ridge. Migration modeling predicted historical region-wide panmixia for most regions, with Pulley Ridge appearing to be a potential sink population. The GOM appears to demonstrate stronger evidence of vertical connectivity compared to elsewhere in the Tropical Western Atlantic, which may be the result of oceanographic variability and/or lack of local selection at depth. These findings are consistent with previous studies identifying genetic connectivity of broadcast-spawning corals across broad spatial scales and highlight the potential importance of mesophotic habitats in the GOM as larval sources to geographically distant populations.
Although widely studied, the process of how mind wandering occurs and is subsequently sustained still remains unclear. Moreover, the traditional concept of mind wandering tendency/frequency based on ...the self- or probe-caught methods alone is incoherent and problematic. We developed a new approach to characterize the mind wandering process by combining the self-caught and probe-caught methods to estimate the time of focus and time of mind wandering separately, and examined their relationship to working memory capacity. Participants performed an OSPAN task and subsequently a basic Mindfulness Meditation Task (focus on breath). During the meditation task, participants indicated when they became aware that they were mind wandering (self-caught method), or were asked if they were mind wandering when probed (probe-caught method). Results showed that time of focus but not time of mind wandering increased with greater working memory capacity. This suggests that individuals with higher working memory capacity were able to focus on the current task longer, but had little effect on the ability to monitor and terminate mind wandering once it occurred. The theoretical and methodological implications of this new approach are discussed.
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