Editorial: Ecosystem Services and Disservices Provided by Plant-Feeding Predatory Arthropods

Editorial of the Research Topic issue on Ecosystem Services and Disservices Provided by Plant-Feeding Predatory Arthropod

Identification and application of bacterial volatiles to attract a generalist aphid parasitoid from laboratory to greenhouse assays

BACKGROUND: Recent studies have shown that microorganisms emit volatile compounds that affect insect behaviour. However, it remains largely unclear whether microbes can be exploited as a source of attractants to improve biological control of insect pests. In this study, we used a combination of coupled gas chromatography electroantennography (GC-EAG) and Y-tube olfactometer bioassays to identify attractive compounds in the volatile extracts of three bacterial strains that are associated with the habitat of the generalist aphid parasitoid Aphidius colemani, and to create mixtures of synthetic compounds to find attractive blends for A. colemani. Subsequently, the most promising blend was evaluated in two-choice cage experiments under greenhouse conditions. RESULTS: GC-EAG analysis revealed 20 compounds that were linked to behaviourally attractive bacterial strains. A mixture of two EAG-active compounds, styrene and benzaldehyde applied at a respective dose of 1 μg and 10 ng, was more attractive than the single compounds or the culture medium of the bacteria in Y-tube olfactometer bioassays. Application of this synthetic mixture under greenhouse conditions resulted in significant attraction of the parasitoids, and outperformed application of the bacterial culture medium. CONCLUSION: Compounds isolated from bacterial blends were capable of attracting parasitoids both in laboratory and greenhouse assays, indicating that microbial culture are an effective source of insect attractants. This opens new opportunities to attract and retain natural enemies of pest species and to enhance biological pest control

Conserved Class of Queen Pheromones Stops Social Insect Worker Reproduction

Dissertação de mestrado em Gestão, apresentada à Faculdade de Economia da Universidade de Coimbra, sob a orientação de Patrícia Pereira da SilvaEm 2011, a crise política e financeira de Portugal atingiu um nível crítico, levando à queda do governo, assim como ao pedido de ajuda à denominada Troika, constituída pelo (Fundo Monetário Internacional, Banco Central Europeu e Comunidade Europeia). As recomendações da Troika sobre a política energética Portuguesa basearam-se em torno de medidas que potenciem a eficiência energética, ou seja, medidas que permitam poupar e otimizar consumo de energia. No entanto, sobre as energias renováveis, foi pedida especial atenção, em particular, em tecnologias menos desenvolvidas (incluindo o fotovoltaico), nas quais se deverá efetuar uma análise rigorosa em termos de custos e consequências para o preço da energia. Outra das recomendações da Troika passou por uma revisão em baixo do preço pago pela tarifa (Feed-in tariff), com o intuito de que esse valor não produza compensações alegadamente excessivas para os investidores neste setor. Atendendo às novas constrições anteriormente apresentadas, e aos elevados custo de investimento que as Fontes de Energias Renováveis apresentam, nomeadamente, no setor fotovoltaico, a respetiva avaliação económica assume um papel primordial. É, assim, objetivo desta dissertação estimar da forma mais correta a rendibilidade do investimento, sendo, para tal, desenvolvida uma metodologia de análise de projetos de investimento, usando o método discounted cash flow (DCF) – Free Cash Flow to the firm, bem como, compreender e analisar quais os principais fatores que estão inerentes a um projeto de Fontes de Energia Renovável, nomeadamente, na análise do Levelized Cost Of Electricity (LCOE) e paridade com a rede elétrica. Deste modo, pretende-se uma reanálise do ponto de vista económico de projetos com origem em fontes de energia renovável

Prognostic value of myocardial perfusion scintigraphy in type 2 diabetic patients with mild, stable angina pectoris

Aim: To determine the prognostic value of reversible myocardial perfusion defects on myocardial perfusion scintigraphy (MPS) in patients with type 2 diabetes mellitus and mild anginal complaints. Methods and results: In the MERIDIAN trial, patients with diabetes mellitus type 2, stable, mild anginal symptoms (Canadian Cardiovascular Society classification (CCS) I-II/IV) and reversible perfusion defects were randomized to either continued pharmacological treatment or early invasive treatment. In this sub analysis, the severity of the myocardial perfusion defect was related to the occurrence of cardiac death and non-fatal myocardial infarction, in 319 patients (63% male, 65 ± 9 years). During follow-up (2.2 ± 0.6 years), 14 patients had a cardiac event: 3 in 171 patients without myocardial ischemia and 11 in 148 patients with myocardial ischemia. Annual event rates rose from 0.8% to 5.8% with increasing severity of myocardial ischemia. Multivariable analysis identified the presence of severe myocardial ischemia (hazard ratio (HR) 5.45, 95%CI 1.89-15.71) and insulin use (HR 4.00, 95%CI 1.25-12.75) as independent predictors of cardiac events. Conclusions: Type 2 diabetics with mild anginal symptoms with no or moderate myocardial ischemia have a low annual cardiac event rate. In patients with severe myocardial ischemia event rate increased 3-6 fold

Cardiac autonomic neuropathy in patients with diabetes and no symptoms of coronary artery disease: comparison of 123I-metaiodobenzylguanidine myocardial scintigraphy and heart rate variability

PURPOSE The purpose of this study was to evaluate the prevalence of cardiac autonomic neuropathy (CAN) in a cohort of patients with type 2 diabetes, truly asymptomatic for coronary artery disease (CAD), using heart rate variability (HRV) and (123)I-metaiodobenzylguanidine ((123)I-mIBG) myocardial scintigraphy. METHODS The study group comprised 88 patients with type 2 diabetes prospectively recruited from an outpatient diabetes clinic. In all patients myocardial perfusion scintigraphy, CAN by HRV and (123)I-mIBG myocardial scintigraphy were performed. Two or more abnormal tests were defined as CAN-positive (ECG-based CAN) and one or fewer as CAN-negative. CAN assessed by (123)I-mIBG scintigraphy was defined as abnormal if the heart-to-mediastinum ratio was 25%, or the total defect score was >13. RESULTS The prevalence of CAN in patients asymptomatic for CAD with type 2 diabetes and normal myocardial perfusion assessed by HRV and (123)I-mIBG scintigraphy was respectively, 27% and 58%. Furthermore, in almost half of patients with normal HRV, (123)I-mIBG scintigraphy showed CAN. CONCLUSION The current study revealed a high prevalence of CAN in patients with type 2 diabetes. Secondly, disagreement between HRV and (123)I-mIBG scintigraphy for the assessment of CAN was observed.Cardiovascular Aspects of Radiolog