University of Coimbra

About: University of Coimbra is a education organization based out in Coimbra, Portugal. It is known for research contribution in the topics: Population & Mitochondrion. The organization has 14318 authors who have published 43067 publications receiving 994733 citations. The organization is also known as: UC & Universidade dos Estudos Gerais.

Impact of the electricity mix and use profile in the life-cycle assessment of electric vehicles

Abstract: This paper presents an environmental and an economic Life-Cycle Assessment (LCA) for conventional and electric vehicle technologies, focusing mainly on the primary energy source and the vehicle operation phase Greenhouse Gas (GHG) emissions. A detailed analysis of the electricity mix was performed, based on the contribution of each type of primary energy source and their variation along a year. Three mixes were considered, with different life cycle GHG intensity: one mainly based in fossil sources, a second one with a large contribution from nuclear and a third one with a significant share of renewable energy sources. The conventional vehicle technology is represented by gasoline and diesel International Combustion Engine Vehicles (ICEVs), while the electric technology is represented by Plug-in Hybrid Electric Vehicles (PHEVs) and Battery Electric Vehicles (BEVs). Real world tests were performed for representative compact and sub-compact EVs. The use profile of the vehicle was based on data acquired by a real time data acquisition system installed in the vehicles. The results show that a mix with a large contribution from Renewable Energy Sources (RESs) does not always translate directly into low GHG emissions for EVs due to the high variability of these sources. The driving profile under different scenarios was also analyzed, showing that an aggressive style can increase the energy consumption by 47%. The tests also showed that the use of climate control can increase the energy consumption between 24 and 60%. Compared with other technologies, EVs can be more sustainable from an environmental and economic perspective; however, three main factors are required: improvement of battery technology, an eco-driving attitude and an environmental friendly electricity mix.

Search for direct third-generation squark pair production in final states with missing transverse momentum and two b-jets in √s = 8 TeV pp collisions with the ATLAS detector

Abstract: The results of a search for pair production of supersymmetric partners of the Standard Model third-generation quarks are reported. This search uses 20.1 fb-1 of pp collisions at sqrt{s}=8 TeV collected by the ATLAS experiment at the Large Hadron Collider. The lightest bottom and top squarks (b1 and t1 respectively) are searched for in a final state with large missing transverse momentum and two jets identified as originating from b-quarks. No excess of events above the expected level of Standard Model background is found. The results are used to set upper limits on the visible cross section for processes beyond the Standard Model. Exclusion limits at the 95% confidence level on the masses of the third-generation squarks are derived in phenomenological supersymmetric R-parity-conserving models in which either the bottom or the top squark is the lightest squark. The b1 is assumed to decay via b1->b chi0 and the t via t1->b chipm, with undetectable products of the subsequent decay of the chipm due to the small mass splitting between the chipm and the chi0.

Search for new phenomena in dijet events using 37 fb-1 of pp collision data collected at √s=13 TeV with the ATLAS detector

Abstract: Dijet events are studied in the proton-proton collision dataset recorded at root s = 13 TeV with the ATLAS detector at the Large Hadron Collider in 2015 and 2016, corresponding to integrated lumino ...

Beneficial Effects of Dietary Polyphenols on Gut Microbiota and Strategies to Improve Delivery Efficiency.

Abstract: The human intestine contains an intricate ecological community of dwelling bacteria, referred as gut microbiota (GM), which plays a pivotal role in host homeostasis. Multiple factors could interfere with this delicate balance, including genetics, age, antibiotics, as well as environmental factors, particularly diet, thus causing a disruption of microbiota equilibrium (dysbiosis). Growing evidences support the involvement of GM dysbiosis in gastrointestinal (GI) and extra-intestinal cardiometabolic diseases, namely obesity and diabetes. This review firstly overviews the role of GM in health and disease, then critically reviews the evidences regarding the influence of dietary polyphenols in GM based on preclinical and clinical data, ending with strategies under development to improve efficiency of delivery. Although the precise mechanisms deserve further clarification, preclinical and clinical data suggest that dietary polyphenols present prebiotic properties and exert antimicrobial activities against pathogenic GM, having benefits in distinct disorders. Specifically, dietary polyphenols have been shown ability to modulate GM composition and function, interfering with bacterial quorum sensing, membrane permeability, as well as sensitizing bacteria to xenobiotics. In addition, can impact on gut metabolism and immunity and exert anti-inflammatory properties. In order to overcome the low bioavailability, several different approaches have been developed, aiming to improve solubility and transport of dietary polyphenols throughout the GI tract and deliver in the targeted intestinal regions. Although more research is still needed, particularly translational and clinical studies, the biotechnological progresses achieved during the last years open up good perspectives to, in a near future, be able to improve the use of dietary polyphenols modulating GM in a broad range of disorders characterized by a dysbiotic phenotype.