Green beach vegetation dynamics explained by embryo dune development

Sandy coastlines are dynamic environments with potential for biodiverse habitats, such as green beaches. Green beach vegetation can develop on nutrient-poor beaches landward from embryo dunes. It is characterised by low-dynamic coastal wetland habitat such as salt marshes and dune slacks. It has been hypothesised that the establishment of green beach vegetation is facilitated by the shelter provided by embryo dunes, however evidence is lacking. We explored the importance of geomorphology and soil conditions on the species richness and turnover of green beach vegetation over a time period of 10 years. We recorded 107 plots along 11 transects over a gradient from beach to dune on the island of Schiermonnikoog, the Netherlands. We characterised transect geomorphology at transect level and soil conditions and vegetation at plot level in 2006 and 2016. We found that the green beach vegetation was highly dynamic, total plant cover increased by 62% within 10 years. In 2006 beach width was an important factor in explaining species richness, with the highest number of species occurring on narrow beaches with a large volume of embryo dunes. In 2016, species richness was positively associated with the build-up of organic matter. Overall species richness declined relative to 2006 and was accompanied by an increase in elevation due to sand burial and the expansion of embryo dune volume. Our data suggests that geomorphology influenced the vegetation indirectly by affecting sand burial rate. Plant species richness declined less at sheltered conditions where sand burial was limited, allowing the build-up of organic matter. This indicates a time-dependent relationship between the development of embryo dunes and plant species richness: embryo dunes can be a source of shelter, thus increasing species richness, but can compete for space over time, lowering species richness again. Our results are relevant for engineering and management of biodiverse sandy shores

Influenza vaccination of healthcare workers in acute-care hospitals: a case-control study of its effect on hospital-acquired influenza among patients

<p>Abstract</p> <p>Background</p> <p>In acute-care hospitals, no evidence of a protective effect of healthcare worker (HCW) vaccination on hospital-acquired influenza (HAI) in patients has been documented. Our study objective was to ascertain the effectiveness of influenza vaccination of HCW on HAI among patients.</p> <p>Methods</p> <p>A nested case-control investigation was implemented in a prospective surveillance study of influenza-like illness (ILI) in a tertiary acute-care university hospital. Cases were patients with virologically-confirmed influenza occurring ≥ 72 h after admission, and controls were patients with ILI presenting during hospitalisation with negative influenza results after nasal swab testing. Four controls per case, matched per influenza season (2004-05, 2005-06 and 2006-07), were randomly selected. Univariate and multivariate conditional logistic regression models were fitted to assess factors associated with HAI among patients.</p> <p>Results</p> <p>In total, among 55 patients analysed, 11 (20%) had laboratory-confirmed HAI. The median HCW vaccination rate in the units was 36%. The median proportion of vaccinated HCW in these units was 11.5% for cases vs. 36.1% for the controls (<it>P </it>= 0.11); 2 (20%) cases and 21 (48%) controls were vaccinated against influenza in the current season (<it>P </it>= 0.16). The proportion of ≥ 35% vaccinated HCW in short-stay units appeared to protect against HAI among patients (odds ratio = 0.07; 95% confidence interval 0.005-0.98), independently of patient age, influenza season and potential influenza source in the units.</p> <p>Conclusions</p> <p>Our observational study indicates a shielding effect of more than 35% of vaccinated HCW on HAI among patients in acute-care units. Investigations, such as controlled clinical trials, are needed to validate the benefits of HCW vaccination on HAI incidence in patients.</p

Gaia on-board metrology: basic angle and best focus

The Gaia payload ensures maximum passive stability using a single material, SiC, for most of its elements. Dedicated metrology instruments are, however, required to carry out two functions: monitoring the basic angle and refocusing the telescope. Two interferometers fed by the same laser are used to measure the basic angle changes at the level of $\mu$as (prad, micropixel), which is the highest level ever achieved in space. Two Shack-Hartmann wavefront sensors, combined with an ad-hoc analysis of the scientific data are used to define and reach the overall best-focus. In this contribution, the systems, data analysis, procedures and performance achieved during commissioning are presentedComment: 18 pages, 14 figures. To appear in SPIE proceedings 9143-30. Space Telescopes and Instrumentation 2014: Optical, Infrared, and Millimeter Wav

Regulation of pentose catabolic pathway genes of Aspergillus niger

The aim of this study was to obtain a better understanding of the pentose catabolism in Aspergillus niger and the regulatory systems that affect it. To this end, we have cloned and characterised the genes encoding A. niger L-arabitol dehydrogenase (ladA) and xylitol dehydrogenase (xdhA), and compared the regulation of these genes to other genes of the pentose catabolic pathway. This demonstrated that activation of the pathway depends on two transcriptional regulators, the xylanolytic activator (XlnR) and an unidentified L-arabinose specific regulator (AraR). These two regulators affect those genes of the pentose catabolic pathway that are related to catabolic conversion of their corresponding inducers (D-xylose and L-arabinose, respectively)

Statistical decadal predictions for sea surface temperatures: a benchmark for dynamical GCM predictions

Accurate decadal climate predictions could be used to inform adaptation actions to a changing climate. The skill of such predictions from initialised dynamical global climate models (GCMs) may be assessed by comparing with predictions from statistical models which are based solely on historical observations. This paper presents two benchmark statistical models for predicting both the radiatively forced trend and internal variability of annual mean sea surface temperatures (SSTs) on a decadal timescale based on the gridded observation data set HadISST. For both statistical models, the trend related to radiative forcing is modelled using a linear regression of SST time series at each grid box on the time series of equivalent global mean atmospheric CO2 concentration. The residual internal variability is then modelled by (1) a first-order autoregressive model (AR1) and (2) a constructed analogue model (CA). From the verification of 46 retrospective forecasts with start years from 1960 to 2005, the correlation coefficient for anomaly forecasts using trend with AR1 is greater than 0.7 over parts of extra-tropical North Atlantic, the Indian Ocean and western Pacific. This is primarily related to the prediction of the forced trend. More importantly, both CA and AR1 give skillful predictions of the internal variability of SSTs in the subpolar gyre region over the far North Atlantic for lead time of 2 to 5 years, with correlation coefficients greater than 0.5. For the subpolar gyre and parts of the South Atlantic, CA is superior to AR1 for lead time of 6 to 9 years. These statistical forecasts are also compared with ensemble mean retrospective forecasts by DePreSys, an initialised GCM. DePreSys is found to outperform the statistical models over large parts of North Atlantic for lead times of 2 to 5 years and 6 to 9 years, however trend with AR1 is generally superior to DePreSys in the North Atlantic Current region, while trend with CA is superior to DePreSys in parts of South Atlantic for lead time of 6 to 9 years. These findings encourage further development of benchmark statistical decadal prediction models, and methods to combine different predictions

What is the 'problem' that outreach work seeks to address and how might it be tackled? Seeking theory in a primary health prevention programme

&lt;b&gt;Background&lt;/b&gt; Preventive approaches to health are disproportionately accessed by the more affluent and recent health improvement policy advocates the use of targeted preventive primary care to reduce risk factors in poorer individuals and communities. Outreach has become part of the health service response. Outreach has a long history of engaging those who do not otherwise access services. It has, however, been described as eclectic in its purpose, clientele and mode of practice; its effectiveness is unproven. Using a primary prevention programme in the UK as a case, this paper addresses two research questions: what are the perceived problems of non-engagement that outreach aims to address; and, what specific mechanisms of outreach are hypothesised to tackle these.&lt;p&gt;&lt;/p&gt; &lt;b&gt;Methods&lt;/b&gt; Drawing on a wider programme evaluation, the study undertook qualitative interviews with strategically selected health-care professionals. The analysis was thematically guided by the concept of 'candidacy' which theorises the dynamic process through which services and individuals negotiate appropriate service use.&lt;p&gt;&lt;/p&gt; &lt;b&gt;Results&lt;/b&gt; The study identified seven types of engagement 'problem' and corresponding solutions. These 'problems' lie on a continuum of complexity in terms of the challenges they present to primary care. Reasons for non-engagement are congruent with the concept of 'candidacy' but point to ways in which it can be expanded.&lt;p&gt;&lt;/p&gt; &lt;b&gt;Conclusions&lt;/b&gt; The paper draws conclusions about the role of outreach in contributing to the implementation of inequalities focused primary prevention and identifies further research needed in the theoretical development of both outreach as an approach and candidacy as a conceptual framework

Patients Enrolled in Large Randomized Clinical Trials of Antiplatelet Treatment for Prevention After Transient Ischemic Attack or Ischemic Stroke Are Not Representative of Patients in Clinical Practice: the Netherlands Stroke Survey

Background and Purpose—Many randomized clinical trials have evaluated the benefit of long-term use of antiplatelet drugs in reducing the risk of new vascular events in patients with a recent transient ischemic attack or ischemic stroke. Evidence from these trials forms the basis for national and international guidelines for the management of nearly all such patients in clinical practice. However, abundant and strict enrollment criteria may limit the validity and the applicability of results of randomized clinical trials to clinical practice. We estimated the eligibility for participation in landmark trials of antiplatelet drugs of an unselected group of patients with stroke or transient ischemic attack from a national stroke survey. Methods—Nine hundred seventy-two patients with transient ischemic at

The Effects of Influenza Vaccination of Health Care Workers in Nursing Homes: Insights from a Mathematical Model

Using a mathematical model to simulate influenza transmission in nursing homes, Carline van den Dool and colleagues find that each additional staff member vaccinated further reduces the risk to patients

The epidemiology and transmission of methicillin-resistant Staphylococcus aureus in the community in Singapore: study protocol for a longitudinal household study.

BACKGROUND/AIM: Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most common multidrug-resistant organisms in healthcare settings worldwide, but little is known about MRSA transmission outside of acute healthcare settings especially in Asia. We describe the methods for a prospective longitudinal study of MRSA prevalence and transmission. METHODS: MRSA-colonized individuals were identified from MRSA admission screening at two tertiary hospitals and recruited together with their household contacts. Participants submitted self-collected nasal, axilla and groin (NAG) swabs by mail for MRSA culture at baseline and monthly thereafter for 6 months. A comparison group of households of MRSA-negative patients provided swab samples at one time point. In a validation sub-study, separate swabs from each site were collected from randomly selected individuals, to compare MRSA detection rates between swab sites, and between samples collected by participants versus those collected by trained research staff. Information on each participant's demographic information, medical status and medical history, past healthcare facilities usage and contacts, and personal interactions with others were collected using a self-administered questionnaire. DISCUSSION/CONCLUSION: Understanding the dynamics of MRSA persistence and transmission in the community is crucial to devising and evaluating successful MRSA control strategies. Close contact with MRSA colonized patients may to be important for MRSA persistence in the community; evidence from this study on the extent of community MRSA could inform the development of household- or community-based interventions to reduce MRSA colonization of close contacts and subsequent re-introduction of MRSA into healthcare settings. Analysis of longitudinal data using whole-genome sequencing will yield further information regarding MRSA transmission within households, with significant implications for MRSA infection control outside acute hospital settings