145 research outputs found
Microcalorimetric Measurement Of The Enthalpies Of Transfer Of A Series Of M-alkoxyphenols From Isotonic Aqueous Solution To Escherichia Coli Cells
Enthalpies of interactions of a series of m-alkoxyphenols with non-growing Escherichia coli suspended in a salt solution have been recorded. These data have been analysed on the assumption that the initial relatively rapid endothermic process represented the transfer of solute from aqueous solution to cells (ΔHtrs) and that the subsequent relatively lengthy exothermic process resulted from the biological consequences of the transfer process itself. The derived values are compared with values of ΔHtrs found for transfer of these solutes from water to octan-1-ol, heptane and propylene carbonate.8292929293
Neighborhood disadvantage across the transition from adolescence to adulthood and risk of metabolic syndrome
This study investigates the association between neighborhood disadvantage from adolescence to young adulthood and metabolic syndrome using a life course epidemiology framework. Data from the United States-based National Longitudinal Study of Adolescent to Adult Health (n = 9500)and a structural equation modeling approach were used to test neighborhood disadvantage across adolescence, emerging adulthood, and young adulthood in relation to metabolic syndrome. Adolescent neighborhood disadvantage was directly associated with metabolic syndrome in young adulthood. Evidence supporting an indirect association between adolescent neighborhood disadvantage and adult metabolic syndrome was not supported. Efforts to improve cardiometabolic health may benefit from strategies earlier in life
Structure optimization effects on the electronic properties of BiSrCaCuO
We present detailed first-principles calculations for the normal state
electronic properties of the high T superconductor
BiSrCaCuO, by means of the linearized augmented plane wave
(LAPW) method within the framework of density functional theory (DFT). As a
first step, the body centered tetragonal (BCT) cell has been adopted, and
optimized regarding its volume, ratio and internal atomic positions by
total energy and force minimizations. The full optimization of the BCT cell
leads to small but visible changes in the topology of the Fermi surface,
rounding the shape of CuO barrels, and causing both the BiO bands,
responsible for the pockets near the \textit{\=M} 2D symmetry point, to dip
below the Fermi level. We have then studied the influence of the distortions in
the BiO plane observed in nature by means of a
orthorhombic cell (AD-ORTH) with space group. Contrary to what has been
observed for the Bi-2201 compound, we find that for Bi-2212 the distortion does
not sensibly shift the BiO bands which retain their metallic character. As a
severe test for the considered structures we present Raman-active phonon
frequencies () and eigenvectors calculated within the frozen-phonon
approximation. Focussing on the totally symmetric A modes, we observe
that for a reliable attribution of the peaks observed in Raman experiments,
both - and a-axis vibrations must be taken into account, the latter being
activated by the in-plane orthorhombic distortion.Comment: 22 pages, 4 figure
Resurgence of vaccine-preventable diseases in Venezuela as a regional public health threat in the Americas
Venezuela’s tumbling economy and authoritarian rule have precipitated an unprecedented humanitarian crisis. Hyperinflation rates now exceed 45,000%, and Venezuela’s health system is in free fall. The country is experiencing a massive exodus of biomedical scientists and qualified healthcare professionals. Reemergence of arthropod-borne and vaccine-preventable diseases has sparked serious epidemics that also affect neighboring countries. In this article, we discuss the ongoing epidemics of measles and diphtheria in Venezuela and their disproportionate impact on indigenous populations. We also discuss the potential for reemergence of poliomyelitis and conclude that action to halt the spread of vaccine-preventable diseases within Venezuela is a matter of urgency for the country and the region. We further provide specific recommendations for addressing this crisis. © 2019 Centers for Disease Control and Prevention (CDC). All rights reserved
Modern pollen rain predicts shifts in plant trait composition but not plant diversity along the Andes–Amazon elevational gradient
This is the final version. Available on open access from Wiley via the DOI in this record. Aims: Terrestrial ecosystems are changing in biodiversity, species composition and functional trait composition. To understand the underlying causes of these changes and predict the long-term resilience of the ecosystem to withstand future disturbances, we can evaluate changes in diversity and composition from fossil pollen records. Although diversity can be well estimated from pollen in temperate ecosystems, this is less clear for the hyperdiverse tropics. Moreover, it remains unknown whether functional composition of plant assemblages can be accurately predicted from pollen assemblage composition. Here, we evaluate how community-weighted mean (CWM) traits and diversity indices change along elevation. Location: Amazon–Andes elevation gradient in Peru. Methods: We used 82 modern pollen samples and 59 vegetation plots along the elevation gradient, and calculated CWM traits and diversity indices for each pollen sample and vegetation plot. We also quantified the degree to which taxa are over- or underrepresented by their pollen, by dividing the relative pollen abundance by the relative basal area abundance in the nearby vegetation survey plots (i.e. the R-rel values). Results: We found that CWM wood density increased, and CWM adult height and leaf area decreased with elevation. This change was well predicted by pollen assemblages, indicating that CWM trait–environment relationships based on pollen abundance data provide meaningful results. Diversity (richness, Shannon and Simpson) decreased with elevation for vegetation plots, but these trends could not be observed from pollen assemblages. Conclusions: Our results demonstrate that more research is needed to develop methods that lead to accurate diversity estimates from pollen data in these tropical ecosystems, but that CWM traits can be calculated from pollen data to assess spatial shifts in functional composition. This opens opportunities to calculate CWM traits from fossil pollen data sets in the tropics, with broad implications for improving our understanding and predictions of forest dynamics, functioning and resilience through time.Nederlandse Organisatie voor Wetenschappelijk Onderzoe
Is it time to change the stereotype of cancer: the expert view
Objectives
Negative public attitudes towards cancer may contribute to delays in presentation and present barriers to providing quality care. This study explored the views of cancer experts regarding the content of public health messages to improve public attitudes to cancer.
Methods
Twenty-one healthcare professionals (HCPs) from a range of backgrounds took part took part in interviews. Interview transcripts were evaluated using thematic analysis focusing on the HCPs views of the prevailing negative stereotype of cancer patients and their recommendations for cancer awareness campaigns that could redress this view.
Results
HCPs contrasted the progress that had been made in the effective management of cancer with popular stereotypes and media representations. Information quality and supply were identified as barriers to changing the cancer stereotype held by the public.
Conclusions
HCPs believe there is a need for more information about cancer in the public domain and it should focus on providing more balanced messages that include information about the improvements that have been achieved in preventing and treating cancer
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