29 research outputs found
A multi-scale modelling framework to guide management of plant invasions in a transboundary context
Background
Attention has recently been drawn to the issue of transboundary invasions, where species introduced and naturalized in one country cross international borders and become problematic in neighbouring countries. Robust modelling frameworks, able to identify the environmental drivers of invasion and forecast the current and future potential distribution of invasive species, are needed to study and manage invasions. Limitations due to the lack of species distribution and environmental data, or assumptions of modelling tools, often constrain the reliability of model predictions.
Methods
We present a multiscale spatial modelling framework for transboundary invasions, incorporating robust modelling frameworks (Multimodel Inference and Ensemble Modelling) to overcome some of the limitations. The framework is illustrated using Hakea sericea Schrad. (Proteaceae), a shrub or small tree native to Australia and invasive in several regions of the world, including the Iberian Peninsula. Two study scales were considered: regional scale (western Iberia, including mainland Portugal and Galicia) and local scale (northwest Portugal). At the regional scale, the relative importance of environmental predictors sets was evaluated and ranked to determine the main general drivers for the species distribution, while the importance of each environmental predictor was assessed at the local scale. The potential distribution of H. sericea was spatially projected for both scale areas.
Results
Model projections for western Iberia suggest that a large area is environmentally suitable in both Portugal and Spain. Climate and landscape composition sets were the most important determinants of this regional distribution of the species. Conversely, a geological predictor (schist lithology) was more important in explaining its local-scale distribution.
Conclusions
After being introduced to Portugal, H. sericea has become a transboundary invader by expanding in parts of Galicia (Spain). The fact that a larger area is predicted as environmentally suitable in Spain raises concerns regarding its potential continued expansion. This highlights the importance of transboundary cooperation in the early management of invasions. By reliably identifying drivers and providing spatial projections of invasion at multiple scales, this framework provides insights for the study and management of biological invasions, including the assessment of transboundary invasion risk.This work was funded by FEDER funds through the Operational Programme
for Competitiveness Factors - COMPETE and by National Funds through
FCT - Foundation for Science and Technology under the project PTDC/AAGMAA/4539/2012
/ FCOMP-01-0124-FEDER-027863 (IND_CHANGE). J. Vicente
is supported by POPH/FSE funds and by National Funds through FCT -
Foundation for Science and Technology through Post-doctoral grant
SFRH/BPD/84044/2012. D.M. Richardson acknowledges support from the
DST-NRF Centre of Excellence for Invasion Biology and the National
Research Foundation (grant 85417).info:eu-repo/semantics/publishedVersio
Selection of tomato genotypes for processing with high zingiberene content, resistant to pests
Effects of vitamin-B complex supplementation on periodontal wound healing
Background: Reports have demonstrated that nutrient supplements, in particular vitamin-B complex (Vit-B), can positively influence wound healing processes. However, limited information is available on the effects of Vit-B on periodontal wound healing. Methods: A total of 30 patients (13 males, 17 females) presenting with generalized moderate to severe chronic periodontitis were enrolled in this study. All subjects presented >= two teeth in the same sextant with probing depth (PD) >= 5 mm and bleeding upon probing (BOP) in need of access flap surgery (AFS). This study was a randomized, double-masked, placebo-controlled clinical trial. Subjects were instructed to take one capsule a day of either Vit-B (50 mg of the following: thiamine HCl, riboflavin, niacinamide, d-calcium pantothenate, and pyridoxine HCl; 50 mu g each of d-biotin and cyanocobalamin; and 400 mcg of folate) or placebo for 30 days following AFS. Clinical attachment levels (CAL) and N-benzoyl-dl-arginine-2-naphthylamide (BANA) test scores were measured at baseline and at 90 and 180 days following surgical intervention. Assessments of the healing response were also performed using BOP, gingival index (GI), and plaque index (PI) at baseline and 7, 14, 30, 90, and 180 days. The mean results of each parameter were averaged within a group. Differences between groups were analyzed by using repeated measures analysis of variance (ANOVA). Results: Both groups experienced comparable levels of PD reduction following AFS (test: -1.57 +/- 0.34; control: -1.50 +/- 0.21). Changes in mean CAL were more favorable in Vit-B supplemented subjects (test: +0.41 +/- 0.12; control: -0.52 +/- 0.23; P=0.024). Stratified data demonstrated significantly better results for the test group in both shallow (test: -0.08 +/- 0.03; control: -1.11 +/- 0.27; P=0.032) and deep sites (test: +1.69 +/- 0.31; control: +0.74 +/- 0.23; P=0.037). No significant differences were observed between groups regarding PI, GI, and BOP. BANA test values were significantly reduced in both groups after surgical treatment and no significant differences were noted between groups. Conclusion: Vitamin B-complex supplement in combination with AFS resulted in statistically significant superior CAL gains when compared to placebo.7671084109