New methods for testing phylogenetic niche conservatism with an application to the Squamates of Madagascar

Phylogenetic niche conservatism (PNC), whereby closely-related species share similar ecological preferences, is often assumed to play a role in speciation processes. However, this trend is challenged by cases of phylogenetic niche divergence (PND), whereby closely-related species diverge in their ecological preferences. I examine the incidence of PNC and PND in the endemic scaled reptiles (Order, Squamata) of Madagascar. Firstly, I develop new tools to test for PNC and PND for a pair of species or populations. I introduce a novel measure of niche overlap and a null biogeographic test. I begin by comparing their performance with existing methods and case studies and I find the outputs from this new methodology to be consistent with evolutionary theory. I then conduct an assessment on the sensitivity of these tools to common sources of uncertainty identified in other niche-based methodologies. The methodology shows sensitivity to environmental spatial autocorrelation but not size of background region or sampling bias. I then applied these tools to sister taxa of squamates in Madagascar. I find cases of both PNC and PND and a tendency for niche conservatism in regions of high topographic complexity. In order to have an understanding of factors driving species divergence at a local scale, I also test for character displacement. I find character displacement to also be positively associated with topographic complexity. These findings suggest potential shifts in local scale niche traits and conservatism of broad scale niche traits. Overall in this thesis, I describe novel approaches to the study of PNC and PND. I also propose topographic complexity as an important factor in speciation processes in Madagascar. These findings provide hypotheses on the ecological processes involved in speciation on topographic complex regions while the tools presented in this thesis can be applied to many study systems

A Randomized Double-Blind Study Comparing the Efficacy and Safety of Orlistat Versus Placebo in Obese Patients with Mild to Moderate Hypercholesterolemia

INTRODUCTION: Obesity is a chronic disease and a serious health problem that leads to increased prevalence of diabetes, hypertension, dyslipidemia and gallbladder disease. OBJECTIVE: To evaluate the efficacy of orlistat for weight loss and improved lipid profile compared to placebo in obese patients with hypercholesterolemia, treated over a period of 6 months. METHODOLOGY: In a 6-month, multicenter (10 centers in Portugal), double-blind, parallel, placebo-controlled study, 166 patients, aged 18-65 years, body mass index (BMI) > or = 27 kg/m2, LDL cholesterol > 155 mg/dl, were randomized to a reduced calorie diet (600 kcal/day deficit) plus orlistat three times a day or placebo. Exclusion criteria included triglycerides > 400 mg/dl, severe cardiovascular disease, uncontrolled hypertension, type 1 or 2 diabetes under pharmacological treatment, and gastrointestinal or pancreatic disease. RESULTS: The mean difference in weight from baseline was 5.9% (5.6 kg) in the orlistat group vs. 2.3% (2.2 kg) in the placebo group. In the orlistat group 49% of patients achieved 5-10% weight loss and 8.8% achieved > 10%. The orlistat group showed a significant reduction in total and LDL cholesterol, with similar changes for HDL in both treatment groups. The frequency of gastrointestinal adverse events was slightly higher in the orlistat group than in the placebo group, leading to discontinuation in 7 patients. CONCLUSION: Treatment with orlistat plus a reduced calorie diet for 6 months achieved significant reductions in weight, BMI and lipid parameters

Monovarietal extra-virgin olive oil classification: a fusion of human sensory attributes and an electronic tongue

Olive oil quality grading is traditionally assessed by human sensory evaluation of positive and negative attributes (olfactory, gustatory, and final olfactorygustatory sensations). However, it is not guaranteed that trained panelist can correctly classify monovarietal extra-virgin olive oils according to olive cultivar. In this work, the potential application of human (sensory panelists) and artificial (electronic tongue) sensory evaluation of olive oils was studied aiming to discriminate eight single-cultivar extra-virgin olive oils. Linear discriminant, partial least square discriminant, and sparse partial least square discriminant analyses were evaluated. The best predictive classification was obtained using linear discriminant analysis with simulated annealing selection algorithm. A low-level data fusion approach (18 electronic tongue signals and nine sensory attributes) enabled 100 % leave-one-out cross-validation correct classification, improving the discrimination capability of the individual use of sensor profiles or sensory attributes (70 and 57 % leave-one-out correct classifications, respectively). So, human sensory evaluation and electronic tongue analysis may be used as complementary tools allowing successful monovarietal olive oil discrimination.This work was co-financed by FCT/MEC and FEDER under Program PT2020 (Project UID/EQU/50020/2013); by Fundacao para a Ciencia e Tecnologia under the strategic funding of UID/BIO/04469/2013 unit; and by Project POCTEP through Project RED/AGROTEC-Experimentation network and transfer for development of agricultural and agro industrial sectors between Spain and Portugal