The calculus according to S. F. Lacroix (1765-1843)

Silvestre François Lacroix (Paris. 1765 - ibid., 1843) was not a prominent mathematical researcher, but he was certainly a most influential mathematical book author. His most famous book is a monumental Traité du calcul différentiel et du calcul intégral (three large volumes, 1797-1800; a second edition appeared in 1810-1819) - an encyclopaedic appraisal of 18th-century calculus. He also published many textbooks, one of which is closely associated to this large Traité: the Traité élémentaire du calcul différentiel et du calcul intégral (first edition in 1802; four more editions in Lacroix's lifetime; four posthumous editions). Although most historians acknowledge the great influence of Lacroix's large Traité in early 19th-century mathematics it has not been thoroughly studied. This thesis is a contribution for correcting this omission. The focus is on its first edition, but the second edition and the Traité élémentaire, are also addressed. The thesis starts with a short biography of Lacroix, followed by an overview of the first edition of the large Traité. Next corne five chapters where particular aspects are analyzed in detail: the foundations of the calculus, analytic and differential geometry, approximate integration and conceptions of the integral, types of solutions of differential equations (singular/complete/general integrals, geometrical interpretations, and generality of arbitrary functions), and three aspects related to finite differences and series (the use of subscript indices, types of solutions of finite difference equations, and mixed difference equations); for all these aspects Lacroix's treatment is compared to the 18th-century background, and to his likely sources. Then we examine how the large Traité was adapted to a textbook - the Traité élémentaire, we take a look at the second edition of the large Traité, and conclude the body of the thesis with some final remarks

Using Multi-Agent Transport Simulations to Assess the Impact of EV Charging Infrastructure Deployment

Over the last two decades, electrification has gained importance as a means to decarbonise the transport sector. As the number of Electric Vehicles (EVs)increases, it is important to consider broader system aspects as well, especially when deciding the type, coverage, size and location of the charging infrastructure required. In this article, a Multi-Agent model depicting long distance transport in Sweden is proposed, allowing to simulate different scenarios and enabling a more detailed analysis of the interaction between these vehicles and the charging infrastructure

A role for the small GTPases RAC1 and RAC1b in the modulation of NIS expression: potentiation of therapy with radioactive iodine in differentiated thyroid carcinoma

Introduction or Background: The Sodium Iodide Symporter (NIS) is responsible for active transport of iodide into thyroid follicular cells. The retention of its functional expression in most of the well-differentiated thyroid carcinomas (DTCs) enables the use of radioactive iodine (RAI) for treatment of metastatic disease. Still, about 30% of patients with advanced forms of DTC became refractory to RAI which makes their management very challenging. The main reason for impaired iodide uptake in refractory-DTC is the defective functional expression of NIS. Several molecular players have been described as critical for TSH-induced NIS expression, an example being the p38 mitogenic kinase. In breast cancer cells, the small GTPase RAC1 was shown to mediate the positive impact of p38 kinase activity on NIS expression. We, on the other hand, have previously shown that overexpression of RAC1b, a tumor-related splicing variant of RAC1, is associated with worse outcomes in DTC and correlates with the MAPK-activating BRAFV600E mutation, which has been related to the loss of NIS. Since RAC1 and RAC1b may act in an antagonistic fashion to regulate specific cellular responses, we asked if RAC1b would be implicated in NIS downregulation observed in DTCs. Methods Section: NIS expression levels were analyzed by RT-qPCR in a RAC1/RAC1b expression model system developed in non-transformed thyroid cell lines. A non-radioactive iodide influx assay was used to confirm the impact of RAC1-signaling on the efficacy of iodide uptake. Results Section: We demonstrate that ectopic overexpression of RAC1b is sufficient to decrease TSH-induced NIS expression, antagonizing the positive effect of RAC1 GTPase. Moreover, we clearly document, for the first time in thyroid cells, that both NIS expression and iodide uptake are downregulated upon RAC1 inhibition, supporting the role of canonical RAC1 signaling in promoting TSH-induced NIS expression. Conclusion: Our findings provide evidence that RAC1 and RAC1b signaling are implicated in the regulation of NIS expression in thyroid cells and suggest that RAC1b overexpression may be one of the mechanisms contributing to the low levels of NIS observed in some subgroups of DTCs, antagonizing RAC1 stimulatory effect on the TSH/cAMP-mediated induction of NIS expression.FCT - PTDC/BIAMOL/31787/2017N/

A strategy to gradual implementation of data interoperability

Data interoperability is a major concern on e-government, both from the point of view of service offering and from the point of view of public administration efficiency. This paper purposes an incremental, pragmatic approach to data interoperability. It is argued that integration with minor required initial efforts from institutions is feasible, may provide useful solutions and is a solid ground basis for subsequent evolution. This paper presents general guidelines and model solutions to support this approach. Also, presents a demo implementation that proves feasibility of the purposed models and delivers useful solutions on a specific business e-government scenario. Although still limited in range and demonstrated on a quite specific business environment, it is expected that the analysis and the proposed strategies, solutions and models be of interest on a larger spectrum of data interoperability problems.info:eu-repo/semantics/acceptedVersio

ANCA-positive vasculitis: Clinical implications of ANCA types and titers

INTRODUCTION: Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis is an autoimmune disease that can affect multiple organs, the kidney being one of the most affected. Apart from the diagnostics value of ANCA, they have also been advocated as biomarkers of the disease activity. Recently, the genetic changes found in polyangiitis associated with serine-protease proteinase 3 (PR3)-ANCA or myeloperoxidase (MPO)-ANCA raised the possibility of immune-pathogenic and therapeutic differences. OBJECTIVE: To identify differences in the number of relapses, inflammatory markers, outcomes and renal histology related to the types of ANCA. To analyze the implications of ANCA titers in prognosis. METHOD: A retrospective observational study in a Portuguese tertiary hospital. RESULTS: There were no differences in the progression of renal function, histological pattern and initial treatment with regard to ANCA subtypes. As for the evaluated parameters, there were no significant differences according to the types of ANCA, except for mean CRP values within the normal range, which was 6.3±1.3 mg/L for MPO-ANCA and 12.4±10.14 mg/L for PR3-ANCA (p=0.04). We found that 66.7% of the MPO-ANCA-positive showed no relapses versus 40% in the case of PR3-ANCA-positive. There was no correlation between the ANCA titers at presentation, during remission, and in the last evaluation, and the number of relapses. CONCLUSION: PR3-ANCA patients have a mean CRP value within the normal range significantly higher than that of MPO-ANCA patients (p=0.04), which seems to reveal greater inflammatory activity in the first.info:eu-repo/semantics/publishedVersio

Extensive intracranial involvement with multiple dissections in a case of giant cell arteritis

A 56-year-old man presented with weight loss, articular pain and minor neurological symptoms progressing over 1 month. Neurosonological evaluation suggested occlusion in intracranial segments of the left vertebral artery (VA) and of both internal carotid arteries (ICA) and hypoechoic halo sign in both superficial temporal arteries. The diagnosis of giant cell arteritis was supported by inflammatory markers and confirmed by biopsy. Despite early steroid initiation, he manifested fluctuant vascular deficits and became lethargic. Brain MRI indicated watershed infarcts and intracranial dissections of left VA and both ICA. The patient was stabilised with the association of prednisolone 2 mg/kg, methotrexate and oral anticoagulation. Since then he has been neurologically asymptomatic and control imaging showed only residual intracranial left VA stenosis, with no signs of temporal artery inflammation or new vascular lesions. This is to the best of our knowledge, the first reported clinical case with such an extensive intracranial involvement with multiple dissections

Machine learning for detection and prediction of crop diseases and pests: A comprehensive survey

Considering the population growth rate of recent years, a doubling of the current worldwide crop productivity is expected to be needed by 2050. Pests and diseases are a major obstacle to achieving this productivity outcome. Therefore, it is very important to develop efficient methods for the automatic detection, identification, and prediction of pests and diseases in agricultural crops. To perform such automation, Machine Learning (ML) techniques can be used to derive knowledge and relationships from the data that is being worked on. This paper presents a literature review on ML techniques used in the agricultural sector, focusing on the tasks of classification, detection, and prediction of diseases and pests, with an emphasis on tomato crops. This survey aims to contribute to the development of smart farming and precision agriculture by promoting the development of techniques that will allow farmers to decrease the use of pesticides and chemicals while preserving and improving their crop quality and production.info:eu-repo/semantics/publishedVersio

Novas metodologias para a fermentação alcoólica do soro de queijo

Em Portugal, são diariamente lançados no meio ambiente cerca de 1 milhão de litros de soro de queijo – fracção líquida resultante do fabrico de queijo. O impacte ambiental ocasionado por tal volume de efluentes, com elevada carga orgânica, é enorme. Recorrendo à tecnologia de DNA recombinante, modificou-se uma estirpe floculante de Saccharomyces cerevisiae sendo-lhe conferida capacidade para fermentar lactose. Com esta estirpe foram realizados ensaios de fermentação em contínuo, utilizando como substrato soro de queijo desproteinizado, possibilitando operar a uma taxa de diluição máxima de 0,45 hˉ¹, correspondente a uma produtividade volumétrica em etanol de cerca de 10 gLˉ¹hˉ¹, cerca de 7 vezes superior aos processos actualmente existentes. O processo integrado de recuperação da proteína e fermentação alcoólica permite uma redução superior a 90 % de CQO do soro, o que, por si só, se traduz numa enorme diminuição do impacte ambiental negativo, e, por outro lado, abre a porta à produção de etanol com viabilidade económica.Instituto de Biotecnologia e Química Fina (IBQF); PROLAC; Agência de Inovação; Fundação para a Ciência e Tecnologia (FCT)

Construction of a flocculent saccharomyces cerevisiae fermenting lactose

A flocculent Saccharomyces cerevisiae strain with the ability to express both the LAC4 (coding for b-galactosidase) and LAC12 (coding for lactose permease) genes of Kluyveromyces marxianus was constructed. This recombinant strain is not only able to grow on lactose, but it can also ferment this substrate. To our knowledge this is the first time that a recombinant S. cervisiae has been found to ferment lactose in a way comparable to that of the existing lactose-fermenting yeast strains. Moreover, the flocculating capacity of the strain used in this work gives the process several advantages. On the one hand, it allows for operation in a continuous mode at high cell concentration, thus increasing the system's overall productivity; on the other hand, the biomass concentration in the effluent is reduced, thus decreasing product separation/purification costs.Instituto de Biotecnologia e Química Fina (IBQF).Fundação para a Ciência e a Tecnologia (FCT) - PRAXIS XXI/BD/11306/97