Settlement of Macoma balthica larvae in response to benthic diatom films

The role of multi-species benthic diatom films (BDF) in the settlement of late pediveliger larvae of the bivalve Macoma balthica was investigated in still-water bioassays and multiple choice flume experiments. Axenic diatom cultures that were isolated from a tidal mudflat inhabited by M. balthica were selected to develop BDF sediment treatments characterized by a different community structure, biomass, and amount of extracellular polymeric substances (EPS). Control sediments had no added diatoms. Although all larvae settled and initiated burrowing within the first minute after their addition in still water, regardless of treatment, only 48-52% had completely penetrated the high diatom biomass treatments after 5 min, while on average 80 and 69% of the larvae had settled and burrowed into the control sediments and BDF with a low diatom biomass (<3.5 mu g Chl a g(-1) dry sediment), respectively. The percentage of larvae settling and burrowing into the sediment was negatively correlated with the concentration of Chl a and EPS of the BDF. This suggests higher physical resistance to bivalve penetration by the BDF with higher diatom biomass and more associated sugar and protein compounds. The larval settlement rate in annular flume experiments at flow velocities of 5 and 15 cm s(-1) was distinctly lower compared to the still-water assays. Only 4.6-5.8% of the larvae were recovered from BDF and control sediments after 3 h. Nonetheless, a clear settlement preference was observed for BDF in the flume experiments; i.e., larvae settled significantly more in BDF compared to control sediments irrespective of flow speed. Comparison with the settlement of polystyrene mimics and freeze-killed larvae led to the conclusion that active selection, active secondary dispersal and, at low flow velocities (5 cm s(-1)), passive adhesion to the sediment are important mechanisms determining the settlement of M. balthica larvae in estuarine biofilms

Evolution and biogeography of the Pavetteae tribe

With over 700 species, the Pavetteae are one o f the largest tribes in the subfamily Dialypetalanthoideae (formerly: Ixoroideae). Pavetteae representatives are characterized by a high morphological variation, especially regarding the reproductive characters (e.g., number of seeds per fruit, seed type and placentation). Representatives of the tribe occur throughout the Paleotropics in humid and dry vegetation types. In the Asian-Pacific región ca 300 species are currently described whereas on continental Africa and Madagascar (and Western Indian Ocean Islands) ca 350 and ca 80 species are present, respectively. Recently many new genera have been recognized among the Malagasy Pavetteae species (e.g. Tulearia). In addition, it is clear that within the paleotropical genus Tarenna there will be a split into different genera. Not only is the taxonomic history of the tribe rather complicated, also the biogeographical history and evolutionary patterns of the tribe remain understudied to date. Molecular phylogenetics combined with age inference methods, diversificaron analyses and ancestral area reconstruction clearly indicate that current diversity of the Pavetteae is the result of several dispersal events within the Paleotropical region. Moreover, several shifts in ecological preference have likely driven the evolutionary history within the Pavetteae

Classifying hyperspectral airborne imagery for vegetation survey along coastlines

This paper studies the potential of airborne hyperspectral imagery for classifying vegetation along the Belgian coastlines. Here, the aim is to build vegetation maps using automatic classification. Besides a general linear multiclass classifier (Linear Discriminant Analysis), several strategies for combining binary classifiers are proposed: one based on a hierarchical decision tree, one based on the Hamming distance between the codewords obtained by binary classifiers and one based on the coupling of posterior probabilities. In addition, a new procedure is proposed for spatial classification smoothing. This procedure takes into account spatial information by letting the decision for classification of a pixel depend on the classification probabilities of neighboring pixels. This is shown to render smoother classification images

Settlement of <i>Macoma balthica</i> larvae in response to benthic diatom films

The role of multi-species benthic diatom films (BDF) in the settlement of late pediveliger larvae of the bivalve Macoma balthica was investigated in still-water bioassays and multiple choice flume experiments. Axenic diatom cultures that were isolated from a tidal mudflat inhabited by M. balthica were selected to develop BDF sediment treatments characterized by a different community structure, biomass, and amount of extracellular polymeric substances (EPS). Control sediments had no added diatoms. Although all larvae settled and initiated burrowing within the first minute after their addition in still water, regardless of treatment, only 48-52% had completely penetrated the high diatom biomass treatments after 5 min, while on average 80 and 69% of the larvae had settled and burrowed into the control sediments and BDF with a low diatom biomass (3.5 µg Chl a g1 dry sediment), respectively. The percentage of larvae settling and burrowing into the sediment was negatively correlated with the concentration of Chl a and EPS of the BDF. This suggests higher physical resistance to bivalve penetration by the BDF with higher diatom biomass and more associated sugar and protein compounds. The larval settlement rate in annular flume experiments at flow velocities of 5 and 15cm s1 was distinctly lower compared to the still-water assays. Only 4.6-5.8% of the larvae were recovered from BDF and control sediments after 3h. Nonetheless, a clear settlement preference was observed for BDF in the flume experiments; i.e., larvae settled significantly more in BDF compared to control sediments irrespective of flow speed. Comparison with the settlement of polystyrene mimics and freeze-killed larvae led to the conclusion that active selection, active secondary dispersal and, at low flow velocities (5cm s1), passive adhesion to the sediment are important mechanisms determining the settlement of M. balthica larvae in estuarine biofilms

Identifying coffee: development of a low-cost and robust barcoding assay for wild African Coffea species

With an estimated consumption of more than two billion cups a day, coffee is one of the most popular beverages in the world. Nearly all coffee is produced from the seeds of two species: Coffea arabica (Arabica coffee) and Coffea canephora (Robusta coffee). Both Arabica and Robusta coffee production is threatened by climate fluctuations and disease outbreaks, reducing yields and ravaging coffee plantations. To overcome these challenges, the potential of other wild Coffea species for the improvement of existing coffee varieties or for the development of new varieties has been studied. The Coffea genus consists of circa 130 described species that are mainly found in sub-Saharan Africa and Madagascar. Coffea species on the African continent are more closely related to Arabica and Robusta coffee. Nevertheless, the identification of African Coffea species at species level based on morphological traits can be challenging as several species seem to have overlapping trait characteristics. In this study, we developed a molecular barcoding assay consisting of eight nuclear markers between ca 200 and 800 base pairs long that can be sequenced using Sanger sequencing. Marker regions were selected based on the output of publicly available genotyping-by-sequencing data, ensuring that each Coffea species included in this dataset had a unique allele for at least two out of eight markers. The resulting barcoding assay is a cost-efficient and accessible tool for the molecular identification of wild African Coffea species, facilitating their conservation and their application for the improvement of coffee cultivation

Undetected dysglycaemia common in primary care patients treated for hypertension and/or dyslipidaemia: On the need for a screening strategy in clinical practice. A report from EUROASPIRE IV a registry from the EuroObservational Research Programme of the European Society of Cardiology

Background: Dysglycaemia defined as type 2 diabetes (T2DM) and impaired glucose tolerance (IGT), increases the risk of cardiovascular disease (CVD). The negative impact is more apparent in the presence of hypertension and/or dyslipidaemia. Thus, it seems reasonable to screen for dysglycaemia in patients treated for hypertension and/or dyslipidaemia. A simple screening algorithm would enhance the adoption of such strategy in clinical practice. Objectives: To test the hypotheses (1) that dysglycaemia is common in patients with hypertension and/or dyslipidaemia and (2) that initial screening with the Finnish Diabetes Risk Score (FINDRISC) will decrease the need for laboratory based tests. Methods: 2395 patients (age 18-80 years) without (i) a history of CVD or TDM2, (ii) prescribed blood pressure and/or lipid lowering drugs answered the FINDRISC questionnaire and had an oral glucose tolerance test (OGTT) and HbA1c measured. Results: According to the OGTT 934 (39%) had previously undetected dysglycaemia (T2DM 19%, IGT 20%). Of patients, who according to FINDRISC had a low, moderate or slightly elevated risk 20, 34 and 41% and of those in the high and very high-risk category 49 and 71% had IGT or T2DM respectively. The OGTT identified 92% of patients with T2DM, FPG + HbA1c 90%, FPG 80%, 2hPG 29% and HbA1c 22%. Conclusions: (1) The prevalence of dysglycaemia was high in patients treated for hypertension and/or dyslipidaemia. (2) Due to the high proportion of dysglycaemia in patients with low to moderate FINDRISC risk scores its initial use did not decrease the need for subsequent glucose tests. (3) FPG was the best test for detecting T2DM. Its isolated use is limited by the inability to disclose IGT. A pragmatic strategy, decreasing the demand for an OGTT, would be to screen all patients with FPG followed by OGTT in patients with IFG

The Prognostic Value of Fasting Plasma Glucose, Two-Hour Postload Glucose, and HbA 1c in Patients With Coronary Artery Disease: A Report From EUROASPIRE IV

OBJECTIVE Three tests are recommended for identifying dysglycemia: fasting glucose (FPG), 2-h postload glucose (2h-PG) from an oral glucose tolerance test (OGTT), and glycated hemoglobin A1c (HbA1c). This study explored the prognostic value of these screening tests in patients with coronary artery disease (CAD). RESEARCH DESIGN AND METHODS FPG, 2h-PG, and HbA1c were used to screen 4,004 CAD patients without a history of diabetes (age 18–80 years) for dysglycemia. The prognostic value of these tests was studied after 2 years of follow-up. The primary end point included cardiovascular mortality, nonfatal myocardial infarction, stroke, or hospitalization for heart failure and a secondary end point of incident diabetes. RESULTS Complete information including all three glycemic parameters was available in 3,775 patients (94.3%), of whom 246 (6.5%) experienced the primary end point. Neither FPG nor HbA1c predicted the primary outcome, whereas the 2h-PG, dichotomized as <7.8 vs. ≥7.8 mmol/L, was a significant predictor (hazard ratio 1.38, 95% CI 1.07–1.78; P = 0.01). During follow-up, diabetes developed in 78 of the 2,609 patients (3.0%) without diabetes at baseline. An FPG between 6.1 and 6.9 mmol/L did not predict incident diabetes, whereas HbA1c 5.7–6.5% and 2h-PG 7.8–11.0 mmol/L were both significant independent predictors. CONCLUSIONS The 2h-PG, in contrast to FPG and HbA1c, provides significant prognostic information regarding cardiovascular events in patients with CAD. Furthermore, elevated 2h-PG and HbA1c are significant prognostic indicators of an increased risk of incident diabetes