2,342 research outputs found
The influence of societal individualism on a century of tobacco use: modelling the prevalence of smoking
Smoking of tobacco is predicted to cause approximately six million deaths
worldwide in 2014. Responding effectively to this epidemic requires a thorough
understanding of how smoking behaviour is transmitted and modified. Here, we
present a new mathematical model of the social dynamics that cause cigarette
smoking to spread in a population. Our model predicts that more individualistic
societies will show faster adoption and cessation of smoking. Evidence from a
new century-long composite data set on smoking prevalence in 25 countries
supports the model, with direct implications for public health interventions
around the world. Our results suggest that differences in culture between
societies can measurably affect the temporal dynamics of a social spreading
process, and that these effects can be understood via a quantitative
mathematical model matched to observations
Personalized medicine and hospitalization for heart failure: if we understand it, we may be successful in treating it
Randomized trials in patients with hospitalized heart failure (HHF) continue to frustrate the cardiology community. Promising haemodynamic, structural and biomarker findings from phase 2 studies consistently fail to deliver substantive benefits in larger outcome trials. What underlies these recurrent failures? Why are persistently high readmission and post‐discharge mortality rates not being reduced? Challenging any pre‐conceived ideas about the existence of a ‘typical’ acutely decompensated heart failure patient is fundamental, as is the adoption of a carefully personalized approach. These individuals come from a remarkably heterogeneous group. Surely precise phenotyping should translate to a more successful therapeutic approach
Resting state correlates of subdimensions of anxious affect
Resting state fMRI may help identify markers of risk for affective disorder. Given the comorbidity of anxiety and depressive disorders and the heterogeneity of these disorders as defined by DSM, an important challenge is to identify alterations in resting state brain connectivity uniquely associated with distinct profiles of negative affect. The current study aimed to address this by identifying differences in brain connectivity specifically linked to cognitive and physiological profiles of anxiety, controlling for depressed affect. We adopted a two-stage multivariate approach. Hierarchical clustering was used to independently identify dimensions of negative affective style and resting state brain networks. Combining the clustering results, we examined individual differences in resting state connectivity uniquely associated with subdimensions of anxious affect, controlling for depressed affect. Physiological and cognitive subdimensions of anxious affect were identified. Physiological anxiety was associated with widespread alterations in insula connectivity, including decreased connectivity between insula subregions and between the insula and other medial frontal and subcortical networks. This is consistent with the insula facilitating communication between medial frontal and subcortical regions to enable control of physiological affective states. Meanwhile, increased connectivity within a frontoparietal-posterior cingulate cortex-precunous network was specifically associated with cognitive anxiety, potentially reflecting increased spontaneous negative cognition (e.g., worry). These findings suggest that physiological and cognitive anxiety comprise subdimensions of anxiety-related affect and reveal associated alterations in brain connectivity
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Assessing the consistency of satellite-derived upper tropospheric humidity measurements
Four upper tropospheric humidity (UTH) datasets derived from satellite sounders are evaluated to assess their consistency as part of the activities for the Global Energy and Water Exchanges (GEWEX) water vapor assessment project. The datasets include UTH computed from brightness temperature measurements of the 183.31±1 GHz channel of the Special Sensor Microwave – Humidity (SSM/T-2), Advanced Microwave Sounding Unit-B (AMSU-B), and Microwave Humidity Sounder (MHS) and from channel 12 of the High-resolution Infrared Radiation Sounder (HIRS). The four datasets are generally consistent in the interannual temporal and spatial variability of the tropics. Large positive anomalies peaked over the central equatorial Pacific region during El Niño events in the same phase with the increase of sea surface temperature (SST). Conversely, large negative anomalies were obtained during El Niño events when the tropical-domain average is taken. The weakened ascending branch of the Pacific Walker circulation in the western Pacific and the enhanced descending branches of the local Hadley circulation along the Pacific subtropics largely contributed to widespread drying areas and thus negative anomalies in the upper troposphere during El Niño events as shown in all four datasets. During a major El Niño event, UTH had higher correlations with the coincident precipitation (0.60 to 0.75) and with 200 hPa velocity potential (−0.42 to −0.64) than with SST (0.37 to 0.49). Due to differences in retrieval definitions and gridding procedures, there can be a difference of 3 %–5 % UTH between datasets on average, and larger magnitudes of anomaly values are usually observed in spatial maps of microwave UTH data. Nevertheless, the tropical-domain averaged anomalies of the datasets are close to each other with their differences being mostly less than 0.5 %, and more importantly the phases of the time series are generally consistent for variability studie
Stratigraphy and sedimentology of early Pennsylvanian red beds at Lower Cove, Nova Scotia, Canada: the Little River Formation with redefinition of the Joggins Formation
The coastal cliffs along the eastern shore of Chignecto Bay, Nova Scotia contain one of the finest Carboniferous sections in the world. In 1843, Sir William Logan measured the entire section as the first project of the Geological Survey of Canada, and defined eight stratigraphic divisions. We have re-measured a section corresponding almost exactly with Logan’s Division 5 in bed-by-bed detail. The strata are exposed in the wave-cut platform and low-relief bluffs of a 2 km-long section at Lower Cove, near Joggins, north and south of Little River. This 635.8 metre-thick succession until now has been included within the basal part of the Joggins Formation, and overlies the Boss Point Formation. However, the studied strata are lithologically distinct, and are formally recognized as the new Little River Formation. This formation is bounded by regionally important surfaces and is traceable inland for 30 kilometres from its Lower Cove type section. Facies analysis indicates that it represents the deposits of a well-drained alluvial plain dissected by shallow rivers characterized by flashy flow. It can be clearly distinguished from the underlying Boss Point Formation (Logan’s Division 6) by its much smaller channels, and from the overlying Joggins Formation (Logan’s Division 4) by lack of coal seams and bivalve-bearing limestone beds. Palynological assemblages indicate that the Little River Formation is of probable late Namurian to basal Westphalian (basal Langsettian) age, and is a likely time-equivalent of the informal Grand-Anse formation of southeast New Brunswick.
Resumé
Les falaises côtières longeant le rivage oriental de la baie Chignectou, en Nouvelle-Écosse, abritent l’un des stratotypes carbonifères les plus intéressants dans le monde. Sir William Logan avait mesuré en 1843 l’ensemble du stratotype dans le cadre du premier projet de la Commission géologique du Canada et il avait défini huit divisions stratigraphiques. Nous avons mesuré à nouveau un stratotype correspondant presque exactement dans ses détails couche par couche à la division 5 de Logan. Les strates affleurent dans une plate-forme d’érosion et des falaises de relief émoussé d’un secteur de deux kilomètres de longueur à l’anse Lower, près de Joggins, au nord et au sud de la rivière Little. Cette succession de 635,8 mètres d’épaisseur avait jusqu’à maintenant été incluse à l’intérieur de la partie basale de la Formation de Joggins et elle recouvre la Formation de Boss Point. Les strates étudiées sont cependant lithologiquement distinctes et on les reconnaît officiellement en tant que nouvelle Formation de Little River. Cette formation est limitée par des surfaces importantes à l’échelle régionale; on peut la retracer à l’intérieur des terres sur 30 kilomètres à partir de son stratotype de l’anse Lower. Une analyse du faciès révèle qu’il représente les dépôts d’une plaine alluviale bien drainée, sectionnée par des rivières peu profondes caractérisées par des crues éclair. On peut nettement la distinguer de la Formation sous-jacente de Boss Point (division 6 de Logan), grâce à ses canaux beaucoup plus petits, ainsi que de la Formation sus-jacente de Joggins (division 4 de Logan), par l’absence de couches houillères et de couches de calcaire abritant des
lamellibranches. Les assemblages palynologiques révèlent que la Formation de Little River remonte probablement à la période du Namurien tardif au Westphalien basal (Langsettien basal) et qu’elle constitue vraisemblablement un équivalent chronologique de la Formation officieuse de Grande-Anse dans le sud-est du Nouveau-Brunswick
A randomized controlled trial of dapagliflozin on left ventricular hypertrophy in people with type two diabetes:The DAPA-LVH Trial
AIM: We tested the hypothesis that dapagliflozin may regress left ventricular hypertrophy (LVH) in people with type 2 diabetes (T2D). METHODS AND RESULTS: We randomly assigned 66 people (mean age 67 ± 7 years, 38 males) with T2D, LVH, and controlled blood pressure (BP) to receive dapagliflozin 10 mg once daily or placebo for 12 months. Primary endpoint was change in absolute left ventricular mass (LVM), assessed by cardiac magnetic resonance imaging. In the intention-to-treat analysis, dapagliflozin significantly reduced LVM compared with placebo with an absolute mean change of −2.82g [95% confidence interval (CI): −5.13 to −0.51, P = 0.018]. Additional sensitivity analysis adjusting for baseline LVM, baseline BP, weight, and systolic BP change showed the LVM change to remain statistically significant (mean change −2.92g; 95% CI: −5.45 to −0.38, P = 0.025). Dapagliflozin significantly reduced pre-specified secondary endpoints including ambulatory 24-h systolic BP (P = 0.012), nocturnal systolic BP (P = 0.017), body weight (P < 0.001), visceral adipose tissue (VAT) (P < 0.001), subcutaneous adipose tissue (SCAT) (P = 0.001), insulin resistance, Homeostatic Model Assessment of Insulin Resistance (P = 0.017), and high-sensitivity C-reactive protein (hsCRP) (P = 0.049). CONCLUSION: Dapagliflozin treatment significantly reduced LVM in people with T2D and LVH. This reduction in LVM was accompanied by reductions in systolic BP, body weight, visceral and SCAT, insulin resistance, and hsCRP. The regression of LVM suggests dapagliflozin can initiate reverse remodelling and changes in left ventricular structure that may partly contribute to the cardio-protective effects of dapagliflozin. CLINICALTRIALS.GOV IDENTIFIER: NCT0295681
Shear-free perfect fluids with a solenoidal electric curvature
We prove that the vorticity or the expansion vanishes for any shear-free
perfect fluid solution of the Einstein field equations where the pressure
satisfies a barotropic equation of state and the spatial divergence of the
electric part of the Weyl tensor is zero.Comment: 9 page
Efficacy of noninvasive cardiac imaging tests in diagnosis and management of stable coronary artery disease
Ify R Mordi,1,2 Athar A Badar,2 R John Irving,2 Jonathan R Weir-McCall,1 J Graeme Houston,1 Chim C Lang1,2 1Division of Molecular and Clinical Medicine, University of Dundee, Dundee, UK; 2Department of Cardiology, Ninewells Hospital and Medical School, Dundee, UK Abstract: The aim of this review was to discuss the current literature regarding the utility of noninvasive imaging in diagnosis and management of stable coronary artery disease (CAD) including recent data from large randomized trials assessing diagnosis and prognosis. Current guidelines recommend revascularization in patients with refractory angina and in those with potential prognostic benefit. Appropriate risk stratification through noninvasive assessment is important in ensuring patients are not exposed to unnecessary invasive coronary angiograms. The past 20 years have seen an unprecedented expansion in noninvasive imaging modalities for the assessment of stable CAD, with cardiovascular magnetic resonance and computed tomography complementing established techniques such as myocardial perfusion imaging, echocardiography and exercise electrocardiogram. In this review, we examine the current state-of-the-art in noninvasive imaging to provide an up-to-date analysis of current investigation and management options. Keywords: angina, noninvasive imaging, SPECT, stress echo, cardiovascular magnetic resonance, CT coronary angiograph
Analysis of the Pythium ultimum transcriptome using Sanger and Pyrosequencing approaches
<p>Abstract</p> <p>Background</p> <p><it>Pythium </it>species are an agriculturally important genus of plant pathogens, yet are not understood well at the molecular, genetic, or genomic level. They are closely related to other oomycete plant pathogens such as <it>Phytophthora </it>species and are ubiquitous in their geographic distribution and host rage. To gain a better understanding of its gene complement, we generated Expressed Sequence Tags (ESTs) from the transcriptome of <it>Pythium ultimum </it>DAOM BR144 (= ATCC 200006 = CBS 805.95) using two high throughput sequencing methods, Sanger-based chain termination sequencing and pyrosequencing-based sequencing-by-synthesis.</p> <p>Results</p> <p>A single half-plate pyrosequencing (454 FLX) run on adapter-ligated cDNA from a normalized cDNA population generated 90,664 reads with an average read length of 190 nucleotides following cleaning and removal of sequences shorter than 100 base pairs. After clustering and assembly, a total of 35,507 unique sequences were generated. In parallel, 9,578 reads were generated from a library constructed from the same normalized cDNA population using dideoxy chain termination Sanger sequencing, which upon clustering and assembly generated 4,689 unique sequences. A hybrid assembly of both Sanger- and pyrosequencing-derived ESTs resulted in 34,495 unique sequences with 1,110 sequences (3.2%) that were solely derived from Sanger sequencing alone. A high degree of similarity was seen between <it>P. ultimum </it>sequences and other sequenced plant pathogenic oomycetes with 91% of the hybrid assembly derived sequences > 500 bp having similarity to sequences from plant pathogenic <it>Phytophthora </it>species. An analysis of Gene Ontology assignments revealed a similar representation of molecular function ontologies in the hybrid assembly in comparison to the predicted proteomes of three <it>Phytophthora </it>species, suggesting a broad representation of the <it>P. ultimum </it>transcriptome was present in the normalized cDNA population. <it>P. ultimum </it>sequences with similarity to oomycete RXLR and Crinkler effectors, Kazal-like and cystatin-like protease inhibitors, and elicitins were identified. Sequences with similarity to thiamine biosynthesis enzymes that are lacking in the genome sequences of three <it>Phytophthora </it>species and one downy mildew were identified and could serve as useful phylogenetic markers. Furthermore, we identified 179 candidate simple sequence repeats that can be used for genotyping strains of <it>P. ultimum</it>.</p> <p>Conclusion</p> <p>Through these two technologies, we were able to generate a robust set (~10 Mb) of transcribed sequences for <it>P. ultimum</it>. We were able to identify known sequences present in oomycetes as well as identify novel sequences. An ample number of candidate polymorphic markers were identified in the dataset providing resources for phylogenetic and diagnostic marker development for this species. On a technical level, in spite of the depth possible with 454 FLX platform, the Sanger and pyro-based sequencing methodologies were complementary as each method generated sequences unique to each platform.</p
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