4,630 research outputs found
Ontology-based model abstraction
In recent years, there has been a growth in the use of reference conceptual models to capture information about complex and critical domains. However, as the complexity of domain increases, so does the size and complexity of the models that represent them. Over the years, different techniques for complexity management in large conceptual models have been developed. In particular, several authors have proposed different techniques for model abstraction. In this paper, we leverage on the ontologically well-founded semantics of the modeling language OntoUML to propose a novel approach for model abstraction in conceptual models. We provide a precise definition for a set of Graph-Rewriting rules that can automatically produce much-reduced versions of OntoUML models that concentrate the models’ information content around the ontologically essential types in that domain, i.e., the so-called Kinds. The approach has been implemented using a model-based editor and tested over a repository of OntoUML models
Honey volatiles as a fingerprint for botanical origin: a review on their occurrence on monofloral honeys
Honeys have specific organoleptic characteristics, with nutritional and health benefits, being highly appreciated by consumers, not only in food but also in the pharmaceutical and cosmetic industries. Honey composition varies between regions according to the surrounding flora, enabling its characterization by source or type. Monofloral honeys may reach higher market values than multifloral ones. Honey's aroma is very specific, resulting from the combination of volatile compounds present in low concentrations. The authentication of honey's complex matrix, according to its botanical and/or geographical origin, represents a challenge nowadays, due to the different sorts of adulteration that may occur, leading to the search for reliable marker compounds for the different monofloral honeys. The existing information on the volatiles of monofloral honeys is scarce and disperse. In this review, twenty monofloral honeys and honeydews, from acacia, buckwheat, chestnut, clover, cotton, dandelion, eucalyptus, fir tree, heather, lavender, lime tree, orange, pine, rape, raspberry, rhododendron, rosemary, strawberry tree, sunflower and thyme, were selected for volatile comparison purposes. Taking into consideration the country of origin, the technique of isolation and analysis, the five main volatiles from each of the honeys are compared. Whereas some compounds were found in several types of monofloral honey, and thus not considered good volatile markers, some monofloral honeys revealed characteristic volatile compounds independently of their provenance.Funding: SFRH/BD/117013/2016, UID/AGR/00690/2019,
UID/AMB/50017/2019, MED (UIDB/05183/2020), FEDER, PT2020 PACompete 2020info:eu-repo/semantics/publishedVersio
Chemical characterization and biological properties of royal jelly samples from the mediterranean area
Royal jelly (RJ) is a bee product that has high nutritional value and is beneficial for the human health, earning importance as a functional food. Thus, the characterization of its main biological properties is with high importance. In this work, 6 RJ samples obtained in Morocco, Portugal, and Spain were evaluated in terms of total phenol and flavone/flavonol contents; total protein; 10-hydroxy-2-decenoic acid (10-HDA); volatiles composition; antioxidant and anti-inflammatory properties; and inhibition of tyrosinase, xanthine oxidase (XO), and acetylcholinesterase (AChE) activities. Total phenolic content ranged from 3 to 9 mg gallic acid equivalent/g RJ, and flavone/flavonol content from 0.1 to 0.5 mg quercetin equivalent/g RJ. 10-Hydroxy-2-decenoic acid content varied from 0.9% to 1.2% and total protein from 5.5% to 29.7%. Gas chromatography-flame ionization detector and gas chromatography-mass spectrometry analysis showed RJ volatiles dominated by linolenic acid, 2-decenoic acid, and octanoic acid in variable amounts. The antioxidant activity was monitored through nitric oxide (NO) scavenging activity and hydrogen peroxide (H2O2) scavenging capacity, where the IC50 ranged from 2.3 to 3.4 and 0.2 to 1.5 mg/mL, respectively. Anti-AChE activity IC50 ranged from 0.7 to 4.6 mg/mL, while XO inhibition IC50 ranged from 3.3 to 11.9 mg/mL. The results showed that phenols and flavonoids highly contributed to the RJ biological properties in contrast to 10-HDA and proteins.UID/AMB/50017/2019
UIDB/05183/2020info:eu-repo/semantics/publishedVersio
Foeniculum vulgare Essential Oils: Chemical Composition, Antioxidant and Antimicrobial Activities
The essential oils from Foeniculum vulgare commercial aerial parts and fruits were isolated by hydrodistillation, with different distillation times (30 min, I h, 2 h and 3 h), and analyzed by GC and GC-MS. The antioxidant ability was estimated using four distinct methods. Antibacterial activity was determined by the agar diffusion method. Remarkable differences, and worrying from the quality and safety point of view, were detected in the essential oils. trans-Anethole (31-36%), alpha-pinene (14-20%) and limonene (11-13%) were the main components of the essentials oil isolated from F. vulgare dried aerial parts, whereas methyl chavicol (= estragole) (79-88%) was dominant in the fruit oils. With the DPPH method the plant oils showed better antioxidant activity than the fruits oils. With the TBARS method and at higher concentrations, fennel essential oils showed a pro-oxidant activity. None of the oils showed a hydroxyl radical scavenging capacity >50%, but they showed an ability to inhibit 5-lipoxygenase. The essential oils showed a very low antimicrobial activity. In general, the essential oils isolated during 2 h were as effective, from the biological activity point of view, as those isolated during 3 h.info:eu-repo/semantics/publishedVersio
Ascertaining the degradation state of ceramic tiles : a preliminary non-destructive step in view of conservation treatments
Conserving the cultural heritage is a general concern and the use of non-destructive techniques to characterize ancient materials is important. Serious deterioration effects in environmentally exposed ancient glazed ceramic tiles arise from the development of micro-organisms (algae/fungi) within the pore system. Subsequent biodegradation processes are particularly harmful once the decorated glaze is damaged by exfoliation/detachment.
Three case studies will be addressed: Portuguese polychrome decorated tiles from the interior of two churches (16th–17th century) and from the outdoor of a Palace (18th century). Small tile fragments were directly irradiated in a wavelength-dispersive X-ray fluorescence spectrometer for glaze chemical characterization and subsequently irradiated in a powder diffractometer to assess the phase constitution of both glaze and ceramic body.
Cleaning and conserving these ancient cultural artifacts involve a decontamination process applying innovative non-destructive techniques. The present work is intended as a contribution to diagnose the actual degradation state of ancient tiles in view of future decontamination actions using gamma radiation
ForaminĂferos da passagem Jurássico Inferior-MĂ©dio da Bacia Lusitânica: os perfis da Murtinheira, Sector Setentrional e de Zambujal de Alcaria, Sector Central
A análise da diversidade taxonĂłmica e das abundâncias relativas nas associações de foraminĂferos da passagem Jurássico
Inferior-Médio em dois sectores da Bacia Lusitânica indica que tais associações apresentam diferenças nas suas composições,
aparentemente homogéneas. Assim, as asscoiações de zonas proximais (Perfil de Zambujal Alcaria) são mais abundantes e com
maior diversidade que as registadas em zonas distais (perfil da Murtinheira). Além disso, a maioria dos taxa comuns em ambas as
zonas apresentam diferenças nas suas abundâncias relativas, que aprecem resultar de preferências paleo-ambientais distintas
GRASS UTILIZATION IN GROWING FINISHING BĂŤSARO PIGS (85-107 KG). PERFORMANCE AND CARCASS COMPOSITION
The use of different quantities of vegetables, forages or fresh grass as fodder for growing-finishing pigs is an important factor of the northern Portugal traditional system. The increasing development of swine production in outdoor systems, extensive and organic production, turns to upcoming natural diets, in which grass performs a significant part. With regard to this, some investigation has been made concerning the use of fibre-rich feed ingredients in pig nutrition. Metabolic effects of its ingestion are analysed concerning different sights (economical, social, environmental and physiological ones).
The aim of this work was to study the effects of grass utilization in the diets on performances of finishing BĂsaro pigs. A total of 22 pigs (16 castrated males and 6 females) was housed outdoor and fed ad libitum (37 – 85 kg live weight) with a growing diet and then transferred to an indoor system (with free access to an outdoor area) for 49 days, according to 3 different treatments: 100% concentrate (C), 75% concentrate + ad libitum grass (CE75), 50% concentrate + ad libitum grass (CE50). The grass was supplied and its intake registered on a daily basis. Every 14 days, the pigs were weighted and their back fat (P2 in vivo) measured. After slaughter (average weight of 107 kg LW), yield and ½ left carcass characteristics were controlled. During the outdoor growing phase, the ADG was 513 g/day. During the indoor finishing phase, the increase grass intake was proportional to the reduction of concentrate in the diet. The ADG (g) and the fat deposition (P2 cm) were significantly different (P<0,05) in the 3 treatments (ADG: C=641, CE75=467, CE50=356 and: C=11,4, CE75=+9,5, CE50=+6,2). The empty body weight (kg) was also proportional to the intake of concentrate (C=116,2; CE75=107,7; CE50=102,2). Comparatively to the weight of the body parts, pigs that had higher intake of grass and lower of concentrate showed a higher % of shoulder (P<0,05; C=20,4, CE75=21,7, CE50=22,2) and the pH45min of CE carcasses was significantly higher (P<0,05). As a conclusion, concentrate substitution for grass showed a slower growing rate, thinner carcasses and a high technological quality.
Neverthelles variability (CV %) of the productive parameters at the end of this study were higher in the treatments that included grass: live weight (C= 10,5%; C75=10,7%; C50=14,3%), finishing ADG (C=24%; C75=37%, C50=42%), and final fat (C=37%; C75=32%, C50=52%). These values suggest that the utilization of fibrous feeds in growing-finishing swine may be one of the possible explanations of the more heterogeneous products and carcasses found in the traditional or extensive systems, common users of fibrous feeds in the carcass finishing phase
Diagnosis of pathologies in ancient (seventeenth-eighteenth centuries) decorative blue-and-white ceramic tiles : Green stains in the glazes of a panel depicting Lisbon prior to the 1755 earthquake
Decorative panels of ceramic glazed tiles comprise a valuable cultural heritage in Mediterranean countries. Their preservation requires the development of a systematic scientific approach. Exposure to an open-air environment allows for a large span of deterioration effects. Successfully overcoming these effects demands a careful identification of involved degradation processes. Among these, the development of micro-organisms and concomitant glaze surface staining is a very common effect observed in panels manufactured centuries ago. This paper describes a study on the nature of green stains appearing at the surface of blue-and-white tile glazes from a large decorative panel with more than one thousand tiles, called Vista de Lisboa that depicts the city before the destruction caused by the 1755 earthquake. The characterization of green-stained blue-and-white tile glazes was performed using non-destructive X-ray techniques (diffraction and fluorescence spectrometry) by directly irradiating the surface of small tile fragments, complemented by a destructive scanning electron microscopy (SEM) observation of one fragment. Despite the green staining, analytical X-ray data showed that no deterioration had occurred irrespective of the blue or white color, while complementary SEM-EDX data provided chemical evidence of microorganism colonization at the stained glaze surface
Coordination between proteasome impairment and caspase activation leading to TAU pathology: neuroprotection by cAMP
Neurofibrillary tangles (NFTs) are hallmarks of Alzheimer’s disease (AD). The main component of NFTs is TAU, a highly soluble microtubule-associated protein. However, when TAU is cleaved at Asp421 by caspases it becomes prone to aggregation leading to NFTs. What triggers caspase activation resulting in TAU cleavage remains unclear. We investigated in rat cortical neurons a potential coordination between proteasome impairment and caspase activation. We demonstrate that upon proteasome inhibition, the early accumulation of detergent-soluble ubiquitinated (SUb) proteins paves the way to caspase activation and TAU pathology. This occurs with two drugs that inhibit the proteasome by different means: the product of inflammation prostaglandin J2 (PGJ2) and epoxomicin. Our results pinpoint a critical early event, that is, the buildup of SUb proteins that contributes to caspase activation, TAU cleavage, TAU/Ub-protein aggregation and neuronal death. Furthermore, to our knowledge, we are the first to demonstrate that elevating cAMP in neurons with dibutyryl-cAMP (db-cAMP) or the lipophilic peptide PACAP27 prevents/ diminishes caspase activation, TAU cleavage and neuronal death induced by PGJ2, as long as these PGJ2-induced changes are moderate. db-cAMP also stimulated proteasomes, and mitigated proteasome inhibition induced by PGJ2. We propose that targeting cAMP/PKA to boost proteasome activity in a sustainable manner could offer an effective approach to avoid early accumulation of SUb proteins and later caspase activation, and TAU cleavage, possibly preventing/delaying AD neurodegeneration
An MML embedded approach for estimating the number of clusters
Assuming that the data originate from a finite mixture of multinomial distributions, we study the performance of an integrated Expectation Maximization (EM) algorithm considering Minimum Message Length (MML) criterion to select the number of mixture components. The referred EM-MML approach, rather than selecting one among a set of pre-estimated candidate models (which requires running EM several times), seamlessly integrates estimation and model selection in a single algorithm. Comparisons are provided with EM combined with well-known information criteria – e.g. the Bayesian information Criterion. We resort to synthetic data examples and a real application. The EM-MML computation time is a clear advantage of this method; also, the real data solution it provides is more parsimonious, which reduces the risk of model order overestimation and improves interpretabilityinfo:eu-repo/semantics/publishedVersio
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