Browsing by Issue Date, starting with "2015-03"
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- Comparative analysis between condom use clusters and risk behaviours among portuguese university studentsPublication . Gomes, Alexandra; Nunes, CristinaThe research on condom use has been focused on high-risk individuals, paying less attention to those who have moderate risk or safe sexual conducts. In order to design accurate interventions, potential differences among the condom use behavior groups must be considered. The goal was to assess possible differences in individuals presenting different types of risk behavior. 140 heterosexual university students answered a self-reported questionnaire about their sexual history, condom use habits, sexual self-esteem, sexual satisfaction, sexual control, attitudes towards condoms, self-efficacy to condom use, and emotions and feelings during sexual intercourse. A cluster analysis was conducted using the results about condom use and risk behaviors. Three groups with different risk levels emerged, presenting differences over sexual self-efficacy, attitudes towards condoms, socio-demographic variables, and sexual history. The results suggest the condom use inconsistency is highly associated with other risk behaviors but the contrary does not necessarily happens. Condom use consistent users also presented risk behaviors as smoking and drinking. The group differences suggest the risks were more affected by the combination of lack of skills with a negative attitude toward condoms than by contextual or personal variables. These differences sustain the need of an intervention adjusted to the individual's risk levels, since they differ on skills and beliefs that may hinder or promote the adoption of health behaviors.
- Relation between organizational commitment and professional commitment: an exploratory study conducted with teachersPublication . Figueira, Dora de Jesus Guerreiro; Nascimento, Jose Luis Rocha Pereira do; Almeida, H.The existence of several kinds of commitments in the workplace is well known. However, there are few studies that relate these different commitments or those established by deterministic models. This study explored the relationship between organizational and professional commitment in public higher education professors according to the multidimensional perspective of Meyer and Allen (1991), based on a convenience sample of 219 teachers. The proposed models were estimated through structural equation modeling methodology. Model 1 specified a relationship of direct influence of Professional Commitment on Organizational Commitment and Model 2 established the opposite relationship of direct influence of organizational commitment on professional commitment. Both models presented a good fit to the data without statistically significant differences between them. Nevertheless, the explanatory power of Model 1 was superior to Model 2, due to the fact that it includes a larger number of determinant relationships that are statistically significant. Theoretical and practical implications were discussed and new directions for future research were identified.
- Tools for optimizing management of a spatially variable organic fieldPublication . Panagopoulos, Thomas; de Jesus, Jorge; Ben-Asher, JiftahGeostatistical tools were used to estimate spatial relations between wheat yield and soil parameters under organic farming field conditions. Thematic maps of each factor were created as raster images in R software using kriging. The Geographic Resources Analysis Support System (GRASS) calculated the principal component analysis raster images for soil parameters and yield. The correlation between the raster arising from the PC1 of soil and yield parameters showed high linear correlation (r = 0.75) and explained 48.50% of the data variance. The data show that durum wheat yield is strongly affected by soil parameter variability, and thus, the average production can be substantially lower than its potential. Soil water content was the limiting factor to grain yield and not nitrate as in other similar studies. The use of precision agriculture tools helped reduce the level of complexity between the measured parameters by the grouping of several parameters and demonstrating that precision agriculture tools can be applied in small organic fields, reducing costs and increasing wheat yield. Consequently, site-specific applications could be expected to improve the yield without increasing excessively the cost for farmers and enhance environmental and economic benefits.
- Mattress and pillow for prone positioning for treatment of obstructive sleep apnoeaPublication . Moniri, Armin; Nilsson, Michael; Attia, John; Ejnell, HasseConclusion: The new mattress and pillow for prone positioning (MPP) is efficient in reducing the apnoea-hypopnoea index (AHI) and oxygen desaturation index (ODI) in most patients with obstructive sleep apnoea (OSA), with satisfactory compliance. Objective: The aim of the present study was to evaluate the effect of the prone body and head sleep position on severity of disease in patients with OSA after 4 weeks of adaptation to a mattress and pillow facilitating prone positioning. Methods: Fourteen patients with mild to severe OSA, 11 men and 3 women with a mean AHI of 26 (min, 6; max, 53) and mean ODI of 21 (min, 6; max, 51) were evaluated. Two polysomnographic (PSG) studies were performed. The first PSG study was without any treatment and the second was after 4 weeks of adaptation to the MPP for prone positioning of the body and the head. Results: Mean AHI and ODI decreased from 26 and 21 to 8 and 7, respectively (p < 0.001) with treatment. The mean time spent in the supine position was reduced from 128 to 10 min (p = 0.02) and the prone time increased from 42 to 174 min (p = 0.02) with the MPP. The mean total sleep time was 390 min during the first PSG study night without treatment and 370 min during the second night with the MPP (p = 0.7). Ten patients (71%) reduced their AHI by at least 50% and reached a value < 10 during treatment. All patients managed to sleep on the MPP for > 4 h per night during the 4-week study.
- STC1 interference on calcitonin family of receptors signaling during osteoblastogenesis via adenylate cyclase inhibitionPublication . Terra, Silvia R.; Cardoso, João CR; Félix, Rute; Martins, Leo Anderson M.; Souza, Diogo Onofre G.; Guma, Fatima C. R.; Canario, Adelino; Schein, VanessaStanniocalcin 1 (STC1) and calcitonin gene-related peptide (CGRP) are involved in bone formation/remodeling. Here we investigate the effects of STC1 on functional heterodimer complex CALCRL/RAMP1, expression and activity during osteoblastogenesis. STC1 did not modify CALCRL and ramp 1 gene expression during osteoblastogenesis when compared to controls. However, plasma membrane spatial distribution of CALCRL/RAMP1 was modified in 7-day pre-osteoblasts exposed to either CGRP or STC1, and both peptides induced CALCRL and RAMP1 assembly. CGRP, but not STC1 stimulated cAMP accumulation in 7-day osteoblasts and in CALCRL/RAMP1 transfected HEK293 cells. Furthermore, STC1 inhibited forskolin stimulated cAMP accumulation of HEK293 cells, but not in CALCRL/RAMP1 transfected HEK293 cells. However, STC1 inhibited cAMP accumulation in calcitonin receptor (CTR) HEK293 transfected cells stimulated by calcitonin. In conclusion, STC1 signals through inhibitory G-protein modulates CGRP receptor spatial localization during osteoblastogenesis and may function as a regulatory factor interacting with calcitonin peptide members during bone formation. (C) 2015 Elsevier Ireland Ltd. All rights reserved.
- Environmental factors affecting larval fish community in the salt marsh area of Guadiana estuary (Algarve, Portugal)Publication . Gonçalves, Renata; Correia, Ana Dulce; Atanasova, Natasa; Teodosio, Maria; Ben-Hamadou, Radhouan; Chicharo, LuisSalt marsh areas in the Guadiana estuary are important nursery sites for many fish species of commercial and recreational value. More effective protection measures should be adopted as the area is highly affected by anthropogenic and natural threats. Studying larval fish communities in these impacted nursery areas will be relevant to the management of local ecosystems and to larval fish ecology in general. Spatial and seasonal distribution and the effect of environmental factors on the larval fish community of this ecosystem were studied for one year (April 2010 to March 2011). Larvae were sampled monthly in parallel with phytoplankton and zooplankton. Hydrological data and physical parameters were monitored. A decision tree model was used to assess the influence of environmental factors on the larval fish community. A total of 130 larvae and 1171 eggs were caught. Diplodus sargus, Sardina pilchardus, and Pomatoschistus microps were the most abundant larval fish species. The peaks of fish larvae abundance occurred in March and April. The output of the model demonstrates that the abundance of larval fish is determined by the abundance of eggs, zooplanktonic food, and water flood and flow. This study shows the importance of the Guadiana salt marsh as an area for fish nursery and highlights the need for conservation of this area.
- S-nitrosation and neuronal plasticityPublication . Santos, Ana Isabel; Martinez-Ruiz, A.; Araújo, InêsNitric oxide (NO) has long been recognized as a multifaceted participant in brain physiology. Despite the knowledge that was gathered over many years regarding the contribution of NO to neuronal plasticity, for example the ability of the brain to change in response to new stimuli, only in recent years have we begun to understand how NO acts on the molecular and cellular level to orchestrate such important phenomena as synaptic plasticity (modification of the strength of existing synapses) or the formation of new synapses (synaptogenesis) and new neurons (neurogenesis). Post-translational modification of proteins by NO derivatives or reactive nitrogen species is a non-classical mechanism for signalling by NO. S-nitrosation is a reversible post-translational modification of thiol groups (mainly on cysteines) that may result in a change of function of the modified protein. S-nitrosation of key target proteins has emerged as a main regulatory mechanism by which NO can influence several levels of brain plasticity, which are reviewed in this work. Understanding how S-nitrosation contributes to neural plasticity can help us to better understand the physiology of these processes, and to better address pathological changes in plasticity that are involved in the pathophysiology of several neurological diseases. Linked ArticlesThis article is part of a themed section on Pharmacology of the Gasotransmitters. To view the other articles in this section visit
- Modelling of estuarine response to sea-level rise during the Holocene: Application to the Guadiana Estuary-SW IberiaPublication . Sampath, DMR; Boski, T.; Loureiro, Carlos; Sousa, Carlos A. Mendes da Silva deThis paper focuses on simulations of the morphological evolution of an estuary during sedimentary infilling that accompanied Holocene sea-level rise. The simulations were conducted using the Estuarine Sedimentation Model, which uses a behaviour-oriented approach, supported by the chronostratigraphy of the estuary's sedimentary sequence. Behaviour curves were computed to represent the relationship between the estuarine channel depth below maximum high tide and the net accretion at a given location relative to the average sedimentation rate of the estuary during the Holocene. The model was validated by comparing the observed present-day bathymetry of the Guadiana River Estuary, southeastern Portugal, with the corresponding simulated bathymetries for nine control sections across the estuary. The best fit between simulated and actual sediment surface elevations was obtained along the cross-sections in the sheltered, low-energy environments of the estuary. The accuracy of the sedimentary stratigraphy of the best-fit model was further established using 16 radiocarbon ages obtained from five boreholes in the estuary. The present approach is particularly suitable for simulating long-term morphological evolution in sheltered estuarine environments where tidally driven vertical aggradation dominates at centennial to millennium timescales. However, the accuracy of simulated sediment surface elevations and consequently the robustness of behaviour-type models based on Geographical Information System platforms can be enhanced by incorporating (i) the impacts of nearshore hydrodynamic processes and episodic flood events in highly energetic channels, and (ii) the impacts of cross-currents in meandering channel sections. (C) 2015 Elsevier B.V. All rights reserved.
- Effect of packaging technology on microbiological and sensory quality of a cooked blood sausage, Morcela de Arroz, from Monchique region of PortugalPublication . Pereira, J; Dionísio, Lídia; Patarata, L.; Matos, T. J. S.Morcela de Arroz (MA), a popular Portuguese blood sausage, with high pH and water activity (a(w)), is traditionally commercialized without preservatives and unpacked. This study evaluated the best packaging solution to extend MA shelf life stored at 4 +/- 1 degrees C for 44 days: without packaging (WP), vacuum (VP) and modified atmosphere packaging (MAP) (80% CO2; 20% N-2). Mesophilic (MTVC), psychrotrophic (PTVC), lactic acid bacteria (LAB), pseudomonads, molds and yeasts, Enterobacteriaceae, Listeria monocytogenes, Salmonella spp., Bacillus cereus, Clostridium perfringens, sensory properties, pH, moisture and aw were studied. Moisture and a(w) decreased (p < 0.05) in WP. pH decreased in WP and MAP during storage. MTVC and PTVC counts increased to values around 7 log CFU/g at 44 days of storage. LAB and Enterobacteriaceae counts were higher (p < 0.05) in VP. Pseudomonads were inhibited (p < 0.05) by MAP after 8 days of storage. Sensory parameters were affected (p < 0.05) by packaging and storage time. Globally, MAP performed better. (C) 2014 Elsevier Ltd. All rights reserved.
- ComPassos com histórias : narrativas digitais de caminhaPublication . Carvalho, Isabel Cristina; Bidarra, José; Figueiredo, MauroComPassos com histórias explora o contributo da média-arte locativa para o registo da identidade e das vivências de uma comunidade através da exploração do espaço urbano da Vila de Caminha, geolocalizando narrativas digitais de memórias urbanas e, incitando à (re)descoberta desse espaço, num exercício de deriva pelas memórias dos seus habitantes. O acesso a essas memórias é facilitado por duas vias, num plano digital através de um eBook interativo e num plano físico, real, através de uma aplicação, com tecnologia de Realidade Aumentada, que permite a visualização em formato de pequenos vídeos in loco.
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