Publications

Abstract This Letter focuses the binding between Checkpoint kinase 1 and two molecules with known inhibition potential, C39 and C40. In order to find the most relevant residues the structures were submitted to an optimization process. As expected C39 presented the highest inhibitory power towards Chk1, being this inhibition mode highly dependent on the interactions with Lys38 and Glu91. Glu55 and Asp148 exhibit unfavorable interactions to C39. Glu91 was the most important residues in the binding of C40 to Chk1, while interaction with Lys38, Glu55 and Gly90 resulted in repulsion.

Abstract The relationships among structural and thermodynamic properties of 2-, 3-, and 4-chlorobenzonitrile were investigated, in the present work, using several experimental techniques (Knudsen effusion, differential scanning calorimetry, and combustion calorimetry) and computational studies. The CN center dot center dot center dot Cl intermolecular interactions are weaker in 2-chlorobenzonitrile, reflecting a lower enthalpy of sublimation. The two polymorphic forms of 4-chlorobenzonitrile were observed by differential scanning calorimetry and interpreted in terms of the strength of CN center dot center dot center dot Cl intermolecular interactions. The entropic differentiation due to the pseudosymmetry observed in the crystalline packing of 2-chlorobenzonitrile was evaluated. Using adequate working reactions and the respective standard molar enthalpies of formation, in the gaseous phase, the halogen-cyano intramolecular interaction was also evaluated. The theoretically estimated gas-phase enthalpies of formation were calculated using high-level ab initio molecular orbital calculations at the G3MP2B3 and MP2/cc-pVTZ levels of theory. The computed values support very well the experimental results obtained in this work.

Abstract When we talk about society, education and technology, it becomes clear how technology has been the source of the most expressive changes that occurred in the society of the 20th and early 21st centuries' society. Technology has been pointed out as responsible for transforming several significant aspects of social reality to such an extent that some authors argue that we are facing new forms of organization of the economic system and of society, which the educational system should seek to match and accommodate. In this article, we present different perspectives which we believe can be successful in promoting a sustained and projective reflection on the past, the present and the future of the interrelationships in social, educational and technological spheres and the possible effects on science teaching that they entail. The article addresses five topics deemed relevant to substantiate the reflection on the subject under consideration. We first present some thoughts about the information society, the network metaphor and the collective potential. We continue with a focus on technology and its relation with the "schools that learn". We then argue that digital literacy goes far beyond technological competence and stress how school - and its agents - can play a mediating role between the challenges of the Knowledge Society and new generations. In this context of multiple interlinked dependencies, the article ends with reflections on science education, science teaching and scientific literacy in the information society.

Abstract This work investigates the Portuguese scientific production published in journals indexed in SCOPUS and Web of Science under the topic of Information and Communication Technologies (ICT) in the field of education. The main objective is to characterize the methodological approaches with special emphasis given to qualitative research. The articles have been categorized according to their methodological approaches (i.e., theoretical or empirical studies, including documental and non-documental - experimental, quasi-experimental and non-experimental). The abstracts have also been coded according to their main themes and operative verbs. After collecting all the available information, a database was created in a spreadsheet. One researcher read all the abstracts and decided whether the work was to be included or not in the corpus of analysis. After this, a second researcher reviewed the selection. Whenever an abstract did not present all the required information, the researchers tried to find the complete paper. If they failed to find it the record should be kept nonetheless. After the first researcher coded all the items, the second researcher reviewed the coding. When they disagreed, they discussed carefully the pros and cons and then adopted a solution; if the disagreement persisted they were expected to present their arguments to the senior researcher, who would decide the matter, but it has not been necessary to use this solution. Preliminary results reveal that methods are not always accurately described and that most works consist of non-experimental designs. Thus, more coherent and precise description of methods, especially when using qualitative analysis, is required. Given the perceived predominance of non-experimental approaches when studying ICT in the field of education, further studies must offer a comparative analysis of the results obtained with foreign production. Simultaneously, research must address the relationship between qualitative methods and sociological factors such as authors' sex, institutional affiliation and cooperation, and publishing impact factor. The results will hopefully bring relevant insights to the Portuguese scientific community interested in studying Information and Communication Technologies in the field of education.

Abstract Disinfection of swimming pool water is essential to inactivate pathogenic microorganisms. However chlorine based disinfectants, the most commonly used, are known to lead to the formation of disinfection by-products (DBPs), some of which have been associated with adverse health effects. Precursors of DBPs include the organic matter present in the water used to fill the swimming pool, human body fluids and personal care products (PCPs) used by swimmers and bathers. The increased use, in the last years, of PCPs lead to an increased concern about the fate of PCPs in swimming pool waters and potential health risks of formed DBPs. In this study, the chemical transformations of two salicylates, benzyl salicylate (BzS) and phenyl salicylate (PS), incorporated in several PCPs, in chlorinated water were investigated. High-performance liquid chromatography (HPLC) with UV-diode-array detection (HPLC-UV-DAD) was used to follow the reaction kinetics and HPLC with mass spectrometry (HPLC-MS) was used to tentatively identify the major transformation by-products. Under the experimental conditions used in this work both salicylates reacted with chlorine following pseudo-first order kinetics: rate constant k = (0.0038 +/- 0.0002) min(-1) and half-life t(1/2) = (182 +/- 10) min for BzS and rate constant k = (0.0088 +/- 0.0005) min(-1) and half-life t(1/2) = (79 +/- 4) min for PS (mean +/- standard deviation). The reactions of the two salicylates in chlorinated water led to the formation of DBPs that were tentatively identified as mono- and dichloro- substituted compounds. Most probably they result from an electrophilic substitution of one or two hydrogen atoms in the phenolic ring of both salicylates by one or two chlorine atoms.

Abstract The present study seeks to become a positive contribution to the research and development of e-learning systems by conducting an exploratory evaluation of the opinions of the academic community of the University of Porto about various technical and social dimensions present in the conception and deployment of learning management systems, both in the context of supporting face-to-face education and as technical infrastructure to blended and distance learning programmes. A survey by questionnaire was applied to 504 members of the academic community at the university, and it was found that among the participants there is still great scepticism towards e-learning and technologically mediated education, especially among younger students. Participants also considered that learning management systems presenting a plethora of features are not as desirable as systems focused on providing a pleasant and consistent user experience.

Abstract Educational institutions are not being effective, because they do not give individuals what they need to integrate into postmodern society, nor produce citizens that postmodern society needs. Shortcomings include the scientific literacy and cognitive domain levels attained, with an aggravating waning interest in science among pre-university students. We present an inquiry module, an inquiry dynamic, as an education resource for the study of perturbations of a chemical equilibrium state by pre-university or university students of basic chemistry, to contribute to the relevance and popularity of science, potentiation of science literacy and development of cognition. Here we describe an investigation with pre-university students.

Abstract Technology is getting closer to the classroom. Laptops, tablets, smartphones and mobile phones are devices that go hand in hand with the student's books and exercise books. The ereaders, which are gradually entering the Portuguese market, have some characteristics that may make them a useful tool for teachers and students. In some countries, the digitization of educational material is a reality. This idea reinforce the need of exploitation these technologies among Portuguese students. The purpose of this study was to determine what impact has the use of ereaders and ebooks on learning, more specifically in the interpretation of texts, vocabulary, pronunciation and the reading speed of 23 students in the advanced levels of Cambridge Advance Certificate (CAE) and Cambridge Proficiency Exam (CPE) at International House of Coimbra. To this end, a plan was drafted with four sessions, one for each of the four weeks of the intervention. A survey was also carried out, we observed the sessions and at the end of the intervention, interviews were conducted with six students and the teacher. Was concluded that - at the light of the theoretical framework in which this experiment was based - ereaders and ebooks can be an important factor in motivating students to read and a useful tool for the classroom, due to the similarity with the traditional book, the portability and the large capacity file storage, enabling the effortless transport of several books, dictionaries and other documents. Regarding the technology and according to the testimony of students and teacher, the ereaders still need many improvements, there being some scepticism when compared to tablets with multimedia capabilities for audio, video and web browsing similar to the computers. Paper is still the format that offers greatest comfort to students, especially when it comes to underlining and note-taking. However, in general, they all feel that the ebooks and digital format will eventually play a key role in schools.

Abstract Tryptophan doped carbon dots (Trp-CD) were microwave synthesized. The optimum conditions of synthesizing of the Trp-CD were established by response surface multivariate optimization methodologies and were the following: 2.5 g of glucose and 300 mg of tryptophan diluted in 15 mL of water exposed for 5 min to a microwave radiation of 700 W. Trp-CD have an average size of 20 nm, were fluorescent with a quantum yield of 12.4% and the presence of peroxynitrite anion (ONOO ) provokes quenching of the fluorescence. The evaluated analytical methodology for ONOO detection shows a linear response range from 5 to 25 mu M with a limit of detection of 1.5 mu M and quantification of 4.9 mu M. The capability of the ONOO quantification was evaluated in standard solutions and in fortified serum samples.

Abstract A systematic molecular dynamics study using large simulation boxes has been performed in order to extend the analysis of the mesoscopic segregation behavior observed in ionic liquids of the 1,3-dialkyl-imidazolium bis(trifluoromethylsulfonyl)imide homologous series, [C(n)C(m)im][Ntf(2)] (2 <= n <= 10, 2 <= m <= n). The analyses include the discussion of the structure factors, S(q), in the low-q range (1.6 <= q/nm(-1) <= 20); the confirmation of the periodicity of the polar network of the ionic liquid and its relation to the so-called intermediate peaks; and the characterization of the polar network and the nonpolar regions that are formed along the series using aggregate analyses by means of five different statistical tools. The analyses confirmed that the percolation of the nonpolar regions into a continuous domain occurs when the total number of carbon atoms in the alkyl chains exceeds six but that this is not a sufficient condition for the emergence of a distinct and intense prepeak. The existence of such a peak also requires that the longer alkyl chain contains more than a critical alkyl length (CAL) of five carbon atoms.