549 research outputs found
The interplay between the surface and bottom water environment within the Benguela Upwelling System over the last 70âka
The Benguela Upwelling System (BUS), located between 30 and 20°S, is one of the fundamentalhigh-productivity systems of the world ocean. The BUS has previously been studied in terms of primaryproductivity and ecology over glacial-interglacial timescales; however, the response and coupling with thebenthic environment have received little attention. Here, for the ?rst time, we present a high-resolutionreconstruction of the BUS highlighting the link between surface and benthic productivity and their responseto climatic and oceanographic changes over the last 70 ka. The study is based on benthic foraminiferal faunalanalysis together with analyses of diatom assemblages, grain size of the terrigenous fraction, and stable Oand C isotopic and bulk biogenic components of core GeoB3606-1. We reveal signi?cant shifts in benthicforaminiferal assemblage composition. Tight coupling existed between the surface and bottom waterenvironment especially throughout marine isotope stages 4 and 3 (MIS4 and MIS3). Due to the high exportproduction, the site has essentially experienced continuous low oxygen conditions; however, there are timeperiods where the hypoxic conditions were even more notable. Two of these severe hypoxic periods wereduring parts of MIS4 and MIS3 where we ?nd an inverse relationship between diatom and benthicforaminifera accumulation, meaning that during times of extremely high phytodetritus export we notestrongly suppressed benthic productivity. We also stress the importance of food source for the benthosthroughout the record. Shifts in export productivity are attributed not only to upwelling intensity and?lament front position, but also, regional-global climatic and oceanographic changes had signi?cant impacton the BUS dynamics
Population assessment of future trajectories in coronary heart disease mortality.
Background:
Coronary heart disease (CHD) mortality rates have been decreasing in Iceland since the 1980s, largely
reflecting improvements in cardiovascular risk factors. The purpose of this study was to predict future CHD mortality in
Iceland based on potential risk factor trends.
Methods and findings:
The previously validated IMPACT model was used to predict changes in CHD mortality between 2010 and 2040 among the projected population of Iceland aged 25â74. Calculations were based on combining: i) data on population numbers and projections (Statistics Iceland), ii) population risk factor levels and projections (Refine Reykjavik study), and iii) effectiveness of specific risk factor reductions (published meta-analyses). Projections for three contrasting
scenarios were compared: 1) If the historical risk factor trends of past 30 years were to continue, the declining death rates of past decades would level off, reflecting population ageing. 2) If recent trends in risk factors (past 5 years) continue, this would result in a death rate increasing from 49 to 70 per 100,000. This would reflect a recent plateau in previously falling cholesterol levels and recent rapid increases in obesity and diabetes prevalence. 3) Assuming that in 2040 the entire population enjoys optimal risk factor levels observed in low risk cohorts, this would prevent almost all premature CHD deaths before 2040.
Conclusions:
The potential increase in CHD deaths with recent trends in risk factor levels is alarming both for Iceland and
probably for comparable Western populations. However, our results show considerable room for reducing CHD mortality.
Achieving the best case scenario could eradicate premature CHD deaths by 2040. Public health policy interventions based
on these predictions may provide a cost effective means of reducing CHD mortality in the future
Respirable antisense oligonucleotides: a new drug class for respiratory disease
Respirable antisense oligonucleotides (RASONs), which attenuate specific disease-associated mRNAs, represent a new class of respiratory therapeutics with considerable potential. RASONs overcome previous obstacles that have impeded the development of antisense therapeutics targeting diseases in other organ systems. RASONs are delivered directly to the target tissue via inhalation; their uptake seems to be enhanced by cationic properties inherent in pulmonary surfactant, and, because of the markedly different target properties of mRNA and proteins, they can have very long durations of effect compared with traditional drugs targeting the protein of the same gene. RASONs contain chemical modifications that decrease their degradation by cellular nucleases. However, total insensitivity to nucleases is probably not an optimal design criterion for RASONs, because moderate nuclease sensitivity can prevent their systemic delivery, decreasing the potential for systemic toxicity. EPI-2010 is a 21-mer phosphorothioate RASON that attenuates bronchoconstriction, inflammation and surfactant depletion in preclinical models of human asthma, has a duration of effect of seven days, and seems to undergo minimal systemic delivery
Editor's Choice - Assessment of International Outcomes of Intact Abdominal Aortic Aneurysm Repair over 9 Years
Background: Case mix and outcomes of complex surgical procedures vary over time and between regions. This study analyses peri-operative mortality after intact abdominal aortic aneurysm (AAA) repair in 11 countries over 9 years. Methods: Data on primary AAA repair from vascular surgery registries in 11 countries for the years 2005-2009 and 2010-2013 were analysed. Multivariate adjusted logistic regression analyses were carried out to adjust for variations in case mix. Results: A total of 83,253 patients were included. Over the two periods, the proportion of patients >= 80 years old increased (18.5% vs. 23.1%; p <.0001) as did the proportion of endovascular repair (EVAR) (44.3% vs. 60.6; p <.0001). In the latter period, 25.8% of AAAs were less than 5.5 cm. The mean annual volume of open repairs per centre decreased from 12.9 to 10.6 between the two periods (p <.0001), and it increased for EVAR from 10.0 to 17.1 (p <.0001). Overall, peri-operative mortality fell from 3.0% to 2.4% (p <.0001). Mortality for EVAR decreased from 1.5% to 1.1% (p <.0001), but the outcome worsened for open repair from 3.9% to 4.4% (p = .008). The peri-operative risk was greater for octogenarians (overall, 3.6% vs. 2.1%, p <.0001; open, 9.5% vs. 3.6%, p <.0001; EVAR, 1.8% vs. 0.7%, p <.0001), and women (overall, 3.8% vs. 2.2%, p <.0001; open, 6.0% vs. 4.0%, p <.0001; EVAR, 1.9% vs. 0.9%, p <.0001). Peri-operative mortality after repair of AAAs Conclusions: In this large international cohort, total peri-operative mortality continues to fall for the treatment of intact AAAs. The number of EVAR procedures now exceeds open procedures. Mortality after EVAR has decreased, but mortality for open operations has increased. The peri-operative mortality for small AM treatment, particularly open surgical repair, is still considerable and should be weighed against the risk of rupture. (C) 2017 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.Peer reviewe
Realisation of magnetically and atomically abrupt half-metal/semiconductor interface: Co2FeSi0.5Al0.5/Ge(111)
Halfmetal-semiconductor interfaces are crucial for hybrid spintronic devices. Atomically sharp interfaces with high spin polarisation are required for efficient spin injection. In this work we show that thin film of half-metallic full Heusler alloy Co2FeSi0.5Al0.5 with uniform thickness and B2 ordering can form structurally abrupt interface with Ge(111). Atomic resolution energy dispersive X-ray spectroscopy reveals that there is a small outdiffusion of Ge into specific atomic planes of the Co2FeSi0.5Al0.5 film, limited to a very narrow 1ânm interface region. First-principles calculations show that this selective outdiffusion along the Fe-Si/Al atomic planes does not change the magnetic moment of the film up to the very interface. Polarized neutron reflectivity, x-ray reflectivity and aberration-corrected electron microscopy confirm that this interface is both magnetically and structurally abrupt. Finally, using first-principles calculations we show that this experimentally realised interface structure, terminated by Co-Ge bonds, preserves the high spin polarization at the Co2FeSi0.5Al0.5/Ge interface, hence can be used as a model to study spin injection from half-metals into semiconductors
Early intervention in Portugal: study of professionalsâ perceptions
Early intervention (EI) has been characterized by considerable advances in its domain, which has had great repercussions in the
implementation of the family-centered approach. These changes have had implications in the practices and in the adoption and learning of new values that should be implemented in EI. This study evaluates the professional perspectives regarding familycentered practices in EI programs in Portugal. The results highlight
the importance of effective collaboration and coordination between health, education, and social services and the importance of providing child and family support in a natural context. These results reinforce the need to invest in professional training to improve the
quality of services offered to families in EI.Fundação para a CiĂȘncia e a Tecnologia (FCT) no Ăąmbito do projecto PEst-OE/CED/UI1661/2014 do CIEd
The metabolic syndrome is not associated with homocysteinemia: The Persian Gulf Healthy Heart Study
Background: It is uncertain whether homocysteine
and the metabolic syndrome or its components are related
in the general population, as studies investigating the
association between homocysteine levels and insulin resistance
have shown conflicting results. Methods: In an ancillary
study to the Persian Gulf Healthy Heart Study, a cohort
study of Iranian men and women aged â„25 yr, a random sample
of 1754 subjects were evaluated for the association of
plasma homocysteine levels and the metabolic syndrome using
National Cholesterol Education Program (NCEP)-Adult
Treatment Panel (ATP)-III criteria. Total homocysteine levels
and high sensitivity C-reactive protein (CRP) were determined
by enzyme-linked immunosorbent assays. Results: Subjects
with lower HDL-cholesterol and higher blood pressure
showed significantly higher homocysteine levels (p=0.001
and p<0.0001; respectively). There was no significant difference
in serum levels of homocysteine between subjects with
and without the metabolic syndrome. In multiple logistic regression
analysis, the metabolic syndrome did not show a
significant association with serum homocysteine levels after
adjusting for sex, age, smoking, fruit and vegetable intake
pattern, body mass index, and physical inactivity. Concurrent
elevated CRP levels and the metabolic syndrome also did not
show a significant association with serum homocysteine levels
after adjusting for sex, age, and lifestyle cardiovascular
risk factors. Conclusions: There was no association between
the metabolic syndrome using NCEP-ATPIII criteria and homocysteinemia
in this study. These data refute the hypothesis
that homocysteine levels are influenced by the metabolic
syndrome, at least in general healthy population
Designing and Supporting Extraordinary Work Experience
âThere is a big difference between a lesson that is about the practice and takes place outside of it, and explanations and stories that are part of the practice and take place within itâ (Wenger, Communities of practice. Learning, meaning and identity. Cambridge University Press, New York, 1998, p. 100).
The real world learning experienced by students on placement is highly significant (Morley, Enhancing employability in higher education through work based learning. Palgrave Macmillan, 2018). This chapter focuses on how these experiences can be accelerated from being part of courses to a pivotal event towards studentsâ future development.
The chapter explores emerging areas of practice pedagogy and how innovative design can bridge the theory-practice divide and support structures between university and work. The chapter is contextualised in the higher education landscape where students âwork readinessâ is gaining greater traction and how attributes for employability are developed during university
Vaccine-induced, but not natural immunity, against the Streptococcal inhibitor of complement protects against invasive disease
Highly pathogenic emm1 Streptococcus pyogenes strains secrete the multidomain Streptococcal inhibitor of complement (SIC) that binds and inactivates components of the innate immune response. We aimed to determine if naturally occurring or vaccine-induced antibodies to SIC are protective against invasive S. pyogenes infection. Immunisation with full-length SIC protected mice against systemic bacterial dissemination following intranasal or intramuscular infection with emm1 S. pyogenes. Vaccine-induced rabbit anti-SIC antibodies, but not naturally occurring human anti-SIC antibodies, enhanced bacterial clearance in an ex vivo whole-blood assay. SIC vaccination of both mice and rabbits resulted in antibody recognition of all domains of SIC, whereas naturally occurring human anti-SIC antibodies recognised the proline-rich region of SIC only. We, therefore, propose a model whereby natural infection with S. pyogenes generates non-protective antibodies against the proline-rich region of SIC, while vaccination with full-length SIC permits the development of protective antibodies against all SIC domains
- âŠ