Cognitions and types of communication of mathematics teachers: Illustration of an analytical model in a divided episode

In this article we focus our attention on the classroom and, more specifically, on the actions of the teacher during the teaching process, since we consider that said actions are conditioned or strengthened by their cognitions (beliefs, mathematical knowledge for teaching and objectives). For this reason, we explain and discuss an analytic model in relation to the practice of the teacher, which focuses on their actions, cognitions and type of mathematical communication that promotes (as an exteriorization of cognitions), as well as in their relations. In order to illustrate the modeling process, we use a situation (episode) in which a teacher presents the concept (concept of millesimal) during two different moments. First of all, we tackle what we understand in relation to each of the components of the model and, secondly, we present the modeling process and the relationships between components. Finally, we discuss some of the implications of this type of analysis in the training of teachers

The enthalpies of dissociation of the N-O bonds in two quinoxaline derivatives

The present work reports the first experimental thermochemical study of mono-N-oxides derived from quinoxaline, namely, 3-methoxycarbonyl-2-methyl-quinoxaline N-oxide and 3-ethoxycarbonyl-2-methyl-quinoxaline N-oxide. The values of the enthalpies of formation, in the condensed state, and of the enthalpies of sublimation, derived from static bomb calorimetry and Calvet microcalorimetry measurements, respectively, are combined to derive the standard molar enthalpies of formation in the gaseous phase for these two compounds. From the latter values, the first and second N-O bond dissociation enthalpies for the corresponding di-N-oxides have been obtained. The gas-phase experimental results are also compared with calculated data obtained with a density functional theory approach. Copyright (c) 2008 John Wiley & Sons, Ltd

Caracterização do pão regional do distrito de Viseu e de Pão São

Dissertação de Mestrado em Qualidade e Tecnologia AlimentarO objectivo deste estudo visa a caracterização de diferentes amostras de pão Regional e pão São, procurando encontrar semelhanças e identificar os elementos diferenciadores dos mesmos. As amostras de pão Regional foram recolhidas no distrito de Viseu: Carregal do Sal, Cabanas de Viriato, Santar, Viseu, Mangualde, São Pedro do Sul e São Cipriano. No caso do pão São as amostras foram fornecidas pela empresa produtora, Fábrica do Pão localizada em Seia. Procedeu-se à caracterização física, química e sensorial, tendo sido avaliadas as diferentes propriedades em termos de média e desvio padrão das réplicas efectuadas. Posteriormente, procedeu-se a uma análise estatística, para comparação de médias e avaliação da significância das diferenças, tendo para tal sido usado o teste de Tuckey HSD. Foram ainda calculados os coeficientes de correlação de Pearson. Os resultados foram analisados recorrendo ao software SPSS para o Windows versão 19.0 e Statistic versão 6., sendo realizado o teste de análise de variância "one-way" (ANOVA). Numa fase posterior, os valores obtidos para as características do pão foram sujeitos a uma análise de componentes principais (PCA) e uma análise de Cluster. Em relação aos parâmetros químicos analisados no pão Regional, as amostras apresentaram algumas semelhanças e algumas diferenças, assim como também a nível físico e sensorial. No entanto, no que respeita à análise sensorial, as amostras foram, de modo geral, percepcionadas da mesma forma pelos provadores, não sendo detectadas diferenças significativas. Ainda assim, em termos de apreciação global a amostra preferida foi a da pastelaria Flor de Cabanas. Em relação aos parâmetros químicos, físicose sensoriais do pão São, as amostras mostraram-se semelhantes entre si, o que pode ser explicado por terem basicamente a mesma constituição em termos de ingredientes. Contudo, será de assinalar algumas diferenças em termos de fibra, hidratos de carbono, proteína e cloretos, devido à presença de farinha de tremoço numa das amostras. Quando comparadas as amostras de pão Regional com as de pão São, verificou-se que estas se apresentaram bastante diferentes, quer em termos químicos, físicos ou nível sensorial. Foi possível observar que ao nível sensorial os pães Regionais foram os preferidos pelos provadores.ABSTRACT: The aim of this study is the characterization of different samples of regional bread and healthy bread, trying to identify the similarities and contrasting elements in them. The regional bread samples were collected in the District of Viseu: Carregal do Sal, Cabanas de Viriato, Santar, Viseu, São Pedro do Sul and São Cipriano. The healthy bread samples were provided by the production company "Fábrica do Pão", located in Seia. The physical, chemical and sensory characterization was undertaken, having been avaluted the different proprerties in terms of mean value and standard deviation of the replicas made. Later, we proceeded to a statistical analysis for comparison of means and assessing the significance of the differences, having been used for this the Tukey HSD test. We also calculated the Pearson correlation coefficients. The results were analyzaed using the SPSS software version 19.0 for Windows and Statistica version 6, having been performed an analysis of variance "one way"(ANOVA). At a later stage, the values obtained for the characteristics of bread were subjected to principal components analysis (PCA) and cluster analysis. Regardind the chemical parameters analyzed in the regional bread, the samples showed some similarities and differences, as well as regarding the physical and sensory parameters. However, concerning the sensory analysis, the samples were generally perceived by the panelists in the same way, and no significant differences were observed. Still, in terms of the same way preferred by the panelists the sample from pastry "Flor de Cabanas". With respect to chemical, physical and sensory parameters of the healthy bread, the samples were similar, which can be explained by having basically the same constitution in terms of ingredients. However, there can be noted some differences in terms of fiber, carbohydrates, protein and chlorides, due to the presence of lupine flour in one sample. When comparing the regional bread samples with the healthy bread ones, it was found that they quite different, either at the chemical, physical or sensory levels. It was observed that at the sensory level the regional breads were those preferred by the tasters

Clinical outcome of renal transplant patients after coronary stenting

OBJECTIVE: To assess the clinical outcome of renal transplant patients who developed coronary artery disease and were treated with coronary stenting (TCA-ST). METHODS: A total of 3,334 renal transplants were performed in our service - Hospital do Rim e Hipertensão - HRH (Kidney and Hypertension Hospital) from July, 1998 to November, 2004. During this period, 33 of the renal transplant patients underwent TCA-ST to treat 62 severe stenoses in 54 coronary arteries. A retrospective analysis was performed with renal transplant patients undergoing TCA-ST at HRH. The clinical events were registered using medical charts, medical visits and phone calls. RESULTS: During the 30-month clinical follow-up after TCA-ST, 67% of the patients remained asymptomatic, 18% presented stable angina, 6% presented acute coronary syndrome without ST-segment elevation (ACSWSTE), and 3% presented acute coronary syndrome with ST-segment elevation (ACSSTE). No strokes, CHF or cardiac deaths were observed. Three non-cardiac deaths occurred. A restenosis rate of 9% was observed, which is comparable to those found in studies on drug-eluting stents. CONCLUSION: In conclusion, renal transplant patients who developed CAD and were treated with coronary stenting had a low rate of in-stent restenosis, probably related to the immunosuppressive regimen given to prevent kidney rejection.OBJETIVO: Avaliar a evolução clínica de pacientes submetidos a transplante de rim, portadores de doença arterial coronariana, que foram tratados com implante de stent coronariano (ATC-ST). MÉTODOS: Entre julho de 1998 e novembro de 2004, foram realizados, no total, 3.334 transplantes de rim em nossa Instituição (Hospital do Rim e Hipertensão). Desse total, 33 pacientes previamente submetidos a transplante de rim fizeram ATC-ST para o tratamento de 62 estenoses graves em 54 artérias coronárias, nos quais foi realizada análise retrospectiva. O registro dos eventos clínicos foi feito por meio de análise do prontuário médico, consulta médica e ligações telefônicas. RESULTADOS: No seguimento clínico de 30 meses, após a ATC-ST, observou-se que 67% dos pacientes permaneceram assintomáticos, 18% dos pacientes apresentaram quadro de angina estável, 6% apresentaram síndrome coronariana aguda sem supra de ST e 3% apresentaram síndrome coronariana aguda com supra de ST. Não houve pacientes com acidente vascular cerebral, insuficiência cardíaca congestiva ou morte cardíaca. Houve três mortes não-cardíacas. Foi observado índice de reestenose de 9%, que é comparável ao dos estudos de stent farmacológico. CONCLUSÃO: Concluímos que pacientes submetidos a transplante de rim que desenvolveram doença arterial coronariana e que foram tratados com stent coronariano tiveram baixo porcentual de reestenose clínica, provavelmente relacionado ao regime de imunossupressão administrado para evitar rejeição renal.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Hospital do Rim e HipertensãoUNIFESP, EPM, Hospital do Rim e HipertensãoSciEL

A privacy-preserving user authentication mechanism for smart city mobile apps

In the dawn of the 5G era, the advances in mobile communications have created a suitable environment for the emergence of a wide spectrum of Smart City mobile applications that will play a significant role towards the improvement of citizens' life quality in the upcoming years. It is expected that Smart City mobile applications will allow citizens to access numerous and diverse services, provided by third-party Service Providers, through their mobile devices (e.g., smartphones). However, in order for the emerging Smart City mobile applications to gain the trust of all involved stakeholders and reach their full potential in the 5G market, many security and privacy concerns should be addressed in advance. Towards this direction, this paper proposes a privacy-preserving user authentication mechanism, developed in the context of the Mobilizador5G project, in order to: (a) provide mobile users with efficient and effective means to authenticate towards Service Providers, while preventing user identification and tracking; (b) allow anonymity revocation in case of user misbehavior; (c) avoid multiple user profiles creation on the Service Provider side; and (d) enable easy integration in current mobile application implementations

Cisplatin, fluorouracil in bolus injection, and leucovorin in first-line therapy for advanced gastric cancer as an alternative to protocols with infusional fluorouracil

PURPOSE Gastric cancer (GC) is the fourth most common cancer and the second leading cause of cancer death worldwide. Platinum agents and fluoropyrimidines are the main compounds used in the first-line setting for advanced GC. Given the activity of fluorouracil (FU) bolus, the PFL protocol, a chemotherapy regimen combining cisplatin, FU bolus, and leucovorin, was incorporated at the Brazilian National Cancer Institute, because this schedule does not require hospitalization or infusion pumps. This study aims to evaluate the outcomes of PFL in the first-line setting for patients with advanced GC. MATERIALS AND METHODS This was a retrospective cohort study evaluating patients with advanced GC treated in the first-line setting with cisplatin 80 mg/m2 on day 1 and FU bolus 400 mg/m2 plus leucovorin 20 mg/m2 on days 1, 8, 15, and 22 every 4 weeks, from January 2008 to December 2014. RESULTS A total of 109 patients were enrolled. The median number of cycles received per patient was four (one to 11). Complete responses were achieved in 6.4% and partial responses in 14.7%. Median progression-free survival was 6.3 months (95% CI, 5.08 to 7.58 months) and median overall survival was 8.3 months (95% CI, 6. 79 to 9.87 months). Thirty-four (31.2%) patients were alive in 1 year. Grade 3 and 4 adverse events were experienced by 26.6% and 3.7% of patients, respectively, with dose reduction necessary in 9.1%. CONCLUSION PFL is active in advanced GC and could be an alternative for FU continuous infusion protocols in institutions with limited resources and/or low budget, which is the reality in many nations all over the world

Ixonnexin from Tick Saliva Promotes Fibrinolysis by Interacting with Plasminogen and Tissue-Type Plasminogen Activator, and Prevents Arterial Thrombosis

Tick saliva is a rich source of modulators of vascular biology. We have characterized Ixonnexin, a member of the “Basic-tail” family of salivary proteins from the tick Ixodes scapularis. Ixonnexin is a 104 residues (11.8 KDa), non-enzymatic basic protein which contains 3 disulfide bonds and a C-terminal rich in lysine. It is homologous to SALP14, a tick salivary FXa anticoagulant. Ixonnexin was produced by ligation of synthesized fragments (51–104) and (1–50) followed by folding. Ixonnexin, like SALP14, interacts with FXa. Notably, Ixonnexin also modulates fibrinolysis in vitro by a unique salivary mechanism. Accordingly, it accelerates plasminogen activation by tissue-type plasminogen activator (t-PA) with Km 100 nM; however, it does not affect urokinase-mediated fibrinolysis. Additionally, lysine analogue ε-aminocaproic acid inhibits Ixonnexin-mediated plasmin generation implying that lysine-binding sites of Kringle domain(s) of plasminogen or t-PA are involved in this process. Moreover, surface plasmon resonance experiments shows that Ixonnexin binds t-PA, and plasminogen (KD 10 nM), but not urokinase. These results imply that Ixonnexin promotes fibrinolysis by supporting the interaction of plasminogen with t-PA through formation of an enzymatically productive ternary complex. Finally, in vivo experiments demonstrates that Ixonnexin inhibits FeCl3-induced thrombosis in mice. Ixonnexin emerges as novel modulator of fibrinolysis which may also affect parasite-vector-host interactions

Functional cardiac fibroblasts derived from human pluripotent stem cells via second heart field progenitors

Cardiac fibroblasts (CFs) play critical roles in heart development, homeostasis, and disease. The limited availability of human CFs from native heart impedes investigations of CF biology and their role in disease. Human pluripotent stem cells (hPSCs) provide a highly renewable and genetically defined cell source, but efficient methods to generate CFs from hPSCs have not been described. Here, we show differentiation of hPSCs using sequential modulation of Wnt and FGF signaling to generate second heart field progenitors that efficiently give rise to hPSC-CFs. The hPSC-CFs resemble native heart CFs in cell morphology, proliferation, gene expression, fibroblast marker expression, production of extracellular matrix and myofibroblast transformation induced by TGFβ1 and angiotensin II. Furthermore, hPSC-CFs exhibit a more embryonic phenotype when compared to fetal and adult primary human CFs. Co-culture of hPSC-CFs with hPSC-derived cardiomyocytes distinctly alters the electrophysiological properties of the cardiomyocytes compared to co-culture with dermal fibroblasts. The hPSC-CFs provide a powerful cell source for research, drug discovery, precision medicine, and therapeutic applications in cardiac regeneration.J.L.C. received funding from Coordenação de Aperfeiçoamento de Pessoal de Nível Superior and Fundação de Amparo à Pesquisa do Distrito Federal. The work was funded by NIH R01 HL129798 (T.J.K.); NIH U01 HL134764 (T.J.K.); S10RR025644 (T.J.K.); and the UW Institute for Clinical and Translational Research, grant UL1TR000427, from the Clinical and Translational Science Award of the NCATS/NIH.S