On the need for classification criteria for cast in situ RC beam–column joints according to their stiffness

The purpose of this paper is to draw attention to the lack, in current technical specifications, (i) of guidelines on the modelling of cast in situ reinforced concrete beam–column (RCBC) joints and, more specifically, (ii) for a given RCBC joint, of simplified procedures for evaluating if the fully rigid joint model is acceptable or not, having in view its effective stiffness. This is an important issue because, even though it is widely recognized that RCBC joints are a major source of deformation of cast in situ unbraced RC frames, there is no acknowledged simple procedure to assess the relevance of joint flexibility to the overall structural behaviour—as a consequence, the fully rigid joint model is commonly used without any reference to joint stiffness minimum required values. On the other hand, for steel frames, classification criteria for joints according to their stiffness have already been developed. This paper (i) shows that EN 1993-1-8: 2005 simplified classification criteria for steel joints according to their stiffness are inadequate for cast in situ RCBC joints, (ii) develops a modified version of these criteria, appropriate only for very particular conditions, which maintains their basic hypotheses but considers the specificities of RCBC joints and frames and (iii) in agreement with recently published results, concludes that, in some cases, RCBC joints should not be considered nominally rigid and thus their flexibility should be explicitly accounted for in the analysis of unbraced RC frames. The developed simplified classification criteria apply only to very particular cases—some guidance is therefore also provided on the development of general simplified classification criteria for RCBC joints.     

Bioactive compounds,in vitro antioxidant capacity and Maillard reaction products of raw,boiled and fried garlic (Allium sativum L.)

Garlic is used in many dishes but some of its bioactive compounds are lost when exposed to heat. This study evaluated bioactive compounds, antioxidant activity and Maillard reaction products of raw (RG), boiled (BG) and fried garlic (FG). Total phenolic compounds, flavonoids, allicin and phytosterol were quantified as well as dietary fibres and mineral content. Antioxidant activities of RG, BG and FG were evaluated by oxygen radical absorbance capacity (ORAC), oxidation of β‐carotene/linoleic acid and Rancimat methods. The main results were the following: thermal processing of RG decreased both bioactive compounds and antioxidant capacity, boiling was found to be less aggressive than frying, and strong correlations were obtained between total phenolic compounds and the antioxidant assays. However, phytosterol content was higher in FG than in RG and BG and higher temperatures increased the formation of Maillard reaction products. It was concluded that RG and BG should be preferred for human consumption as they present higher antioxidant capacity.     

Using Proteomics to Understand How Leishmania Parasites Survive inside the Host and Establish Infection

Leishmania is a protozoan parasite that causes a wide range of different clinical manifestations in mammalian hosts. It is a major public health risk on different continents and represents one of the most important neglected diseases. Due to the high toxicity of the drugs currently used, and in the light of increasing drug resistance, there is a critical need to develop new drugs and vaccines to control Leishmania infection. Over the past few years, proteomics has become an important tool to understand the underlying biology of Leishmania parasites and host interaction. The large-scale study of proteins, both in parasites and within the host in response to infection, can accelerate the discovery of new therapeutic targets. By studying the proteomes of host cells and tissues infected with Leishmania, as well as changes in protein profiles among promastigotes and amastigotes, scientists hope to better understand the biology involved in the parasite survival and the host-parasite interaction. This review demonstrates the feasibility of proteomics as an approach to identify new proteins involved in Leishmania differentiation and intracellular survival.     

ECO and Onto.PT: a flexible approach for creating a Portuguese wordnet automatically

A wordnet is an important tool for developing natural language processing applications for a language. However, most wordnets are handcrafted by experts, which limits their growth. In this article, we propose an automatic approach to create wordnets by exploiting textual resources, dubbed ECO. After extracting semantic relation instances, identified by discriminating textual patterns, ECO discovers synonymy clusters, used as synsets, and attaches the remaining relations to suitable synsets. Besides introducing each step of ECO, we report on how it was implemented to create Onto.PT, a public lexical ontology for Portuguese. Onto.PT is the result of the automatic exploitation of Portuguese dictionaries and thesauri, and it aims to minimise the main limitations of existing Portuguese lexical knowledge bases.     

Volatile constituents of cooked bullfrog (Rana catesbeiana) legs

Volatile extracts obtained from pressure-cooked bullfrog legs by simultaneous steam distillation and solvent extraction were analyzed by gas chromatography–mass spectrometry. Although the raw bullfrog legs used in this study contained 0.6% fat only, the extracts were dominated (qualitatively and quantitatively) by lipid oxidation volatiles such as alkanals, alkenals, alkadienals, alkanols and alkenols. Few Maillard volatiles were found, amongst them 2-acetylthiazole, the only sulfur-containing compound found in the extract. This profile of volatiles may be explained by the high proportion of phospholipids and low concentration of sulfur amino acid cystine in raw bullfrog meat, as previously reported by other researchers. Odour activity values (OAV) of volatiles were also estimated and major OAV compounds were: (E,E)-2,4-decadienal, (E,Z)-2,4-decadienal, (E,Z)-2,6-nonadienal, 1-octanol, and (E)-2-nonenal. Some of these potent unsaturated aliphatic aldehydes have also been associated with chicken flavour. This may contribute to flavour resemblances between bullfrog and chicken meat.