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The purpose of this research was to develop a computational tool to ease the process of technical building inspections. Thus, a web-based application was created, supported by a well-structured expert inspection system for the building envelope. This application has a distributed architecture, which allows easy implementation using common technologies. Java and JavaScript programming languages are used, as well as HTML and CSS for the interface. The building inspection application is composed of three main processes, namely: a module to treat correlations between data referring to building pathology (e.g., classification of defects and their causes and the correlations between them); a process to help collect information during the inspection procedure (data entry forms filled dynamically); and a process to update the information stored in the first process (for instance, to include new material in the system). The application is extensible and is capable of inspecting 12 types of building elements and materials used in the building envelope. The first demonstration prototype allows a complete inspection of two types of materials. Tests of the application have revealed the advantages of transposing extensive building pathology information to a computational platform: saving time (no need to insert data after the inspection); guiding the surveyor throughout the inspection (the surveyor's input options are limited); providing an easy-to-use interface, which runs on affordable devices; allowing direct storage of information; and reducing errors and omissions of inspection data, as the system guarantees its consistency. In the future, new functionalities can be developed to improve the application's capabilities. [ABSTRACT FROM AUTHOR]

Remote controlled laboratories had a great push during the COVID-19 pandemic. In fact, they were already out there but lacking in visibility. This external trigger pushed the academy to face a global challenge to start offering remote experiments more consistently and maturely. Instituto Superior Técnico (IST) has been offering several remote experiments since 2000 but with the need for an update due to technological aging. As such, the framework for remote experiments in education (FREE) was created based on new web technologies. In addition to the most diverse experiments that had already been developed, FREE includes two experiments that aimed at advanced-level physics students: the Langmuir probe and the electromagnetic (EM) cavity. Both allow users to configure the various parameters and to access the results in real time or check back later. All this access is done using a browser (on a PC or mobile phone) without the need to install additional software. The results of an experimental execution are stored in a database and are downloadable, allowing users to do various analyses and to determine the corresponding plasma density and temperature. In this paper, we will introduce how FREE was used in the implementation of both experiments and give an insight into their didactic approach, such as: (i) how to perform an experimental execution, (ii) the typical data set obtained with, and (iii) the corresponding analysis necessary for the user to retrieve information from it. [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT) of skin tumors or pre-cancerous lesions and of age-related macular degeneration combines the administration of porphyrins or porphyrin precursors and illumination with red light at the diseased sites. Photosensitizers absorbing light beyond 630 nm where tissues have the highest transmittance produce singlet oxygen, a highly reactive activated oxygen species and a major cytotoxin. The PDT of age-related macular degeneration is performed with red laser light after i.v. injection of verteporfin (Visudyne®) a hydrophobic porphyrin carried by serum lipoproteins whose endocytosis leads to accumulation of the porphyrin in endothelial cells of choroidal neo-vessels. In the PDT of skin cancers, local synthesis of the photosensitizer occurs after topical application of the natural protoporphyrin IX precursor δ-aminolevulinic acid (or its ester forms) on the lesions. In all the cases, the photosensitizers should be rapidly excreted to avoid a long lasting skin photosensitivity. [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT) by porphyrins and related tetrapyrrole derivatives is an emerging new treatment modality of tumors of lung, eosophagus and skin and of age-related macular degeneration. Phase III clinical trials for other applications such as re-stenosis after angioplasty are also underway. Under systemic conditions, the transport of porphyrin photosensitizers by serum low density lipoproteins and their specific delivery to tumor cells and vasculature is a determinant of treatment effectiveness. However, this effectiveness can be improved by increasing the selectivity of the photosensitizer uptake by tumors and by using photosensitizers absorbing light in the 660–800 nm range where tissues have the highest transmittance. Another treatment showing great promise is the PDT of skin cancers after topical application of the protoporphyrin IX precursor delta-aminolevulinic acid (or its ester forms). In all the cases, the photosensitizers should be rapidly excreted to avoid a long lasting skin photosensitivity. [ABSTRACT FROM AUTHOR]

Measurement of the concentration of iron in the skin, if correlated with total body iron stores, may enable better informed decisions on when to initiate, change or stop therapy in hereditary heamochromatosis. Naive haemochromatosis patients with iron overload and with C282Y and/or H63D HFE mutations were evaluated at the following time-points: disease diagnosis, end of the therapy programme, and 6 months after the end of therapy. The distribution and concentration of iron in the skin were assessed by quantitative nuclear microscopy methods, in parallel with serum and plasma iron concentration. Iron content in the liver was determined by nuclear magnetic resonance. Iron accumulated in the epidermis; its concentration increased from outer to inner layers, being maximal in the basal layer (7.33±0.98 μmol/g). At all 3 time-points, most of the iron was associated with the extracellular space. During the phlebotomy programme the iron content of the skin and the liver decreased by a factor of 2. These data suggest that measurements of iron concentration in the epidermis, which is a readily accessible tissue, reflect iron overload in the liver. [ABSTRACT FROM AUTHOR]

Abstract: It is shown that the relationship between the alkyl chain length of 3-alkyl-3′,4′,5,7 tetrahydroxyflavones (FnH) bearing alkyl chains of n =1, 4, 6, 10 carbons and their capacity to counter oxidative damage varies markedly with the nature of the biological system. In Cu2+-induced lipid peroxidation of low-density lipoprotein (LDL), the less hydrophobic short-chain F1H and F4H are probably located in the outer layer of LDL and parallel the reference flavonoid antioxidant, quercetin (Q) as effective inhibitors of lipid peroxidation. A marked inhibition of haemolysis induced in red blood cells (RBC) suspensions by the membrane-permeant oxidant, tert-butylhydroperoxide (t-BuOOH), is observed with F4H and F6H present at concentration in the micromolar range. However, F10H the most hydrophobic FnH is even more effective than Q against both haemolysis and lipid peroxidation as measured by malondialdehyde (MDA) equivalents. In oxidation of RBC by H2O2, at least 50 times more F6H and F10H than by t-BuOOH are required to only partly inhibit haemolysis and MDA production. The F1H, F4H and Q are found rather inactive under these conditions. At concentrations in the micromolar range, a marked protection against the cytotoxic effects of the t-BuOOH-induced oxidative stress in human skin NCTC 2544 keratinocytes is also exhibited by the four FnH antioxidants and is comparable to that of Q. Thus, the four FnH species under study may be considered as potent antioxidants which manifest complementary anti-oxidative actions in biological systems of markedly different complexity. [Copyright &y& Elsevier]

Four polyhydroxylated 2-styrylchromones, structurally related to flavones and cinnamic acid, have been studied. An SC derivative with OH groups only at positions 3′ and 4′ on the styryl moiety and another SC bearing an additional OH group at position 5 on the benzopyrone ring were more potent inhibitors of the Cu2+-induced peroxidation of LDL than the flavonoid quercetin. Fluorescence and absorption spectroscopies suggested that one LDL particle may bind 40 SC molecules. A pulse radiolysis study in pH 7 buffered micellar solutions of neutral TX100 and positively charged CTAB demonstrated that one-electron oxidation by ⋅Br2-, ⋅O2- and tryptophan radicals (⋅Trp) depends strongly on the micellar microenvironment. All SCs were readily oxidized by ⋅O2- in CTAB micelles (rate constants: 6–18×106 M-1 s-1). In TX100 micelles only the SC derivative with OH groups in position 3′ and 4′ reacted with ⋅O2- (rate constant: 1.1×106 M-1 s-1). In CTAB, electron transfer to ⋅Trp radicals was observed for all SCs with rate constants ≥3.2×107 M-1 s-1. In TX100 micelles, this reaction occurred solely with the derivative bearing OH groups only at positions 3′ and 4′. [Copyright &y& Elsevier]