Analysis of the deep chlorophyll maximum across the Azores Front

Physical, chemical and biological observations made in late July and August 1997 across the Azores Front (37ºN, 32ºW to 32ºN, 29ºW) are presented. The objectives of the study were: (1) to analyse horizontal and vertical profiles of temperature, salinity, density, nutrients and chlorophyll-a (Chl a) of the top 350 m; (2) to identify the main differences in the deep Chl a Maximum (DCM) and hydrographic structure between the water masses that pass north and south of the Azores Front; and (3) to estimate phytoplankton primary production in these water masses. Horizontal and vertical profiles of salinity, temperature, density, nutrients and phytoplankton pigments in the top 350 m were analysed. The Front separates two distinct water types: the 18 ºC ModeWater (18MW) of subtropical origin, and the 15 ºC ModeWater (15MW) of sub-polar origin. Differences in the DCM and hydrographic structure between 18 MW and 15 MW were observed in the contour plots of each section. The average Chl a concentration between 5 and 200 m depth decreased significantly from 15 MW to 18 MW. The same pattern was observed for the Chl a concentration at the DCM depth. A vertical one-dimensional model was used to estimate the phytoplankton primary production in the 15 MW and 18 MW and led to an estimated water column average gross primary productivity (GPP) between 1.08 and 2.71 mg C

Evidence from 3-a-side soccer games

The aim of this study was to examine the influence of mixing and separating students by sex in the game performance, as heart rate (HR) demands and rate of perceived exertion (RPE) during 3-a-side small-sided soccer games (SSGs) performed in the context of Physical Education (PE) classes. Twelve students (6 male of 15.33±0.8 years; 1.77±0.10 m; 67.0±4.2 Kg; 21.50±2.5 Kg.m², and; 6 female of 15.00±0.0 years; 1.61±0.01 m; 53.8±9.1 Kg; 19.9±2.3 Kg.m2) performed the SSGs in two conditions: i) separated by sex and ii) mixed-sex. From single-sex to coeducation conditions results showed significant increases in female RPE and HR (14 to 16.1 and 142 to 163, respectively), but a decrease in the number of wrong passes, goals and shooting accuracy (p < 0.05: 80.5 to 15.2; 3.8 to 1.9 and 1.0 to 0.4, respectively). In the male group, only a single significant increase occurred in the total number of passes between the corresponding two conditions (p = 0.023: 12.5 to 14.1). When comparing the two gender groups in the mixed condition, we registered significantly higher values of the total number of passes and number of wrong passes in males than in females (74%), while the RPE was higher in females (p < 0.05). On the contrary, no significant differences between groups were observed in the separated conditions. These findings suggest a trend toward an increase in the perceived exercise intensity, not completely corroborated by HR data, with less technical proficiency for female students, mainly when playing against their male counterparts. PE teachers should be aware that mixing gender during foot-ball related activities may have a negative impact on female performance, which may impact their motivation and skill acquisition.info:eu-repo/semantics/publishedVersio

A new approach for routine quantification of microplastics using Nile Red and automated software (MP-VAT)

Microplastics are widespread contaminants in the environment. However, most identification protocols rely on long and subjective visual counting, which could be improved using staining dyes. Thus, the objective of this work is to identify the best staining dye protocol and create an objective and quick automated counting software for microplastics. Tests were conducted to identify the most appropriate of eight staining dye solutions and of six wavelengths for virgin and weathered synthetic polymers, textile fibers, natural organic matter and filters. Nile Red produced the best results (without interfering in infrared spectra) rendering microplastics fluorescent at 254 nm, but with limited number of fluorescent polymers, and at 470 nm (with orange filter), with fluorescence of plastics as well as natural organic matter (requiring a digestion step). Next, a script was developed in ImageJ for the automatic quantification and characterization in shape (fiber, fragment, particle) and size of fluorescent microplastics, the Microplastics Visual Analysis Tool (MP-VAT). MP-VAT was evaluated, producing recovery rates in the range of 89.0-111.1% in spiked filters under 470 nm. Furthermore, this package is accompanied by a script that sets a scale from a known filter diameter, MP-SCALE, and a script that allows user threshold setting, MP-ACT.publishe

Estudo sobre a influência da compactação na resistência do betão à carbonatação

Trabalho apresentado em 6º Congresso Luso-Moçambicano de Engenharia, 2011 Maputo, MoçambiqueN/

Microplate-based high throughput screening procedure for the isolation of lipid-rich marine microalgae

We describe a new selection method based on BODIPY (4,4-difluoro-1,3,5,7-tetramethyl-4-bora-3a,4a-diaza-s-indacene) staining, fluorescence activated cell sorting (FACS) and microplate-based isolation of lipid-rich microalgae from an environmental sample. Our results show that direct sorting onto solid medium upon FACS can save about 3 weeks during the scale-up process as compared with the growth of the same cultures in liquid medium. This approach enabled us to isolate a biodiverse collection of several axenic and unialgal cultures of different phyla

Identifying a quick and efficient method of removing organic matter without damaging microplastic samples

Natural organic matter may confound the detection of microplastics, requiring a removal step. However, most available protocols are long and lack information on removal efficiency and polymer degradation. Thus, we have determined the digestion efficiency (%) for a pool of organic matter (algae, driftwood, feathers, fish muscle, paraffin, palm oil) for five digestion solutions, hydrogen peroxide (H2O2), hydrogen peroxide with iron catalyst (H2O2 + Fe), potassium hydroxide (KOH), nitric acid (HNO3), and sodium dodecyl sulphate (SDS), under two temperatures (room temperature at 25 °C, 50 °C) and two periods (1, 6 h). H2O2 + Fe and KOH at 50 °C for 1 h had the highest digestion efficiencies, of 65.9% and 58.3% respectively (mostly limited by driftwood and paraffin). Further testing revealed that H2O2 + Fe is more appropriate for plant material and KOH for animal tissue. Weight loss (%), Fourier transform infrared spectrometry and carbonyl index of 9 virgin and 6 weathered polymers (polyethylene, polypropylene, polystyrene, polyethylene terephthalate, polyvinyl chloride, cellulose acetate, nylon) revealed that only identification of cellulose acetate was hindered. Filters were also tested revealing that quartz and glass fibre filters are resistant to these protocols. Thus, a digestion protocol based on H2O2 + Fe or KOH at 50 °C for 1 h may be used on microplastic samples.publishe

The Yellow-­crowned Night Heron Nyctanassa violacea (Aves: Pelecaniformes: Ardeidae) in the Azores and Madeira Archipelagos: a new species for the Western Palearctic

This paper presents and describes the first confirmed occurrence of the Yellow-crowned Night Heron Nyctanassa violacea in the Azores, which also represents the first record for Europe and the Western Palearctic. We also present and discuss subsequent reports of the species in Macaronesia. Several hypotheses may help to explain the occurrence of this species in this part of the Atlantic, including disorientation caused by strong winds and increasing observation pressure. However, further studies are necessary to assess the part played by the different factors in the occurrence of new vagrant individuals/species in Macaronesia

Reconstructed human pigmented skin/epidermis models achieve epidermal pigmentation through melanocore transfer

Funding: We thank the Electron Microscopy Facility at the Instituto Gulbenkian de Ciência, the Pathological Anatomy service in the Instituto Português de Oncologia de Lisboa Francisco Gentil (IPOLFG) and the Histology Facility at CEDOC for technical assistance. This project was supported by Fundação para a Ciência e a Tecnologia (FCT), Portugal through FCT Unit iNOVA4Health – UIDB/04462/2020 and UIDP/04462/2020, a programme financially supported by FCT / Ministério da Ciência, Tecnologia e Ensino Superior, through national funds, grant PTDC/BIA-CEL/29765/2017, PhD fellowships 2020.08528.BD (SLV), PD/BD/128164/2016, PD/BD/137442/2018 (MVN) and PD/BD/136905/2018 (JC) and the FCT Investigator Program to DCB (IF/00501/2014/CP1252/CT0001).The skin acts as a barrier to environmental insults and provides many vital functions. One of these is to shield DNA from harmful UV radiation, which is achieved by skin pigmentation arising as melanin is produced and dispersed within the epidermal layer. This is a crucial defence against DNA damage, photo-ageing and skin cancer. The mechanisms and regulation of melanogenesis and melanin transfer involve extensive crosstalk between melanocytes and keratinocytes in the epidermis, as well as fibroblasts in the dermal layer. Although the predominant mechanism of melanin transfer continues to be debated and several plausible models have been proposed, we and others previously provided evidence for a coupled exo/phagocytosis model. Herein, we performed histology and immunohistochemistry analyses and demonstrated that a newly developed full-thickness 3D reconstructed human pigmented skin model and an epidermis-only model exhibit dispersed pigment throughout keratinocytes in the epidermis. Transmission electron microscopy revealed melanocores between melanocytes and keratinocytes, suggesting that melanin is transferred through coupled exocytosis/phagocytosis of the melanosome core, or melanocore, similar to our previous observations in human skin biopsies. We therefore present evidence that our in vitro models of pigmented human skin show epidermal pigmentation comparable to human skin. These findings have a high value for studies of skin pigmentation mechanisms and pigmentary disorders, whilst reducing the reliance on animal models and human skin biopsies.publishersversionepub_ahead_of_prin

Classificação Geotécnica do maciço rochoso da Pedreira do Monte das Flores – Évora (Portugal)

No âmbito da atualização do processo de homologação da Pedreira do Monte das Flores - Évora, como fornecedora de balastro ferroviário, procedeu-se à classificação geotécnica do maciço rochoso existente no local. Esta exploração possui 96,90 ha de área arrendada estando 70,70 ha concessionados à exploração. Geologicamente, a área estudada pertence à Zona de Ossa-Morena (Maciço de Évora), enquanto parte integrante do Maciço Ibérico que constitui o setor mais ocidental e contínuo da Cadeia Orogénica Varisca na Europa. Também os eventos tectonotérmicos alpinos se fizeram sentir neste maciço de forma atenuada, permitindo a preservação da história geológica mesozóica [Moita, 2008]. A unidade geológica onde se insere a exploração é constituída por litótipos ígneos e metamórficos de idade precâmbrica e paleozóica [Andrade et al., 1976], denotando-se um domínio das formações de rochas eruptivas. Na área estudada ocorre um afloramento de quartzodiorito e granodiorito de grão médio, não porfiróide, onde os minerais mais representativos da rocha são o feldspato potássico, a plagioclase e o quartzo, sem evidenciarem qualquer orientação à vista desarmada [Moita, 2008]. Neste estudo fez-se a descrição geotécnica da qualidade do maciço rochoso que ocorre na Pedreira do Monte das Flores. Por se tratar de um sistema de classificação generalista e correntemente utilizado na avaliação do comportamento geomecânico dos maciços rochosos, utilizou-se a Descrição Geotécnica Básica (“Basic Geotechnical Description”- BGD), proposta pela Sociedade Internacional de Mecânica das Rochas [ISRM, 1981]. O principal objetivo da aplicação desta classificação foi o de efetuar um zonamento geotécnico do maciço rochoso, quer do local atualmente em exploração, quer da área contígua para onde se prevê o alargamento da corta da exploração, com base no reconhecimento geológico e, na amostragem efetuada em locais selecionados para posterior realização de ensaios laboratoriais de caracterização mecânica. Este reconhecimento geológico de superfície permitiu identificar o tipo de rocha presente, determinar as características estruturais e caracterizar a alteração do maciço rochoso, assim como, definir as diferentes famílias de fraturas presentes e quantificar o espaçamento entre as descontinuidades nestas famílias. Com o objetivo de determinar as características mecânicas, tais como, a resistência à compressão uniaxial e o ângulo de atrito das fraturas, foi realizada uma campanha de ensaios laboratoriais e de campo, nomeadamente, o ensaio de resistência à compressão uniaxial, complementado pelo ensaio de carga pontual, de modo a determinar o valor daquela resistência. Realizou-se também o ensaio com o martelo de Schmidt dado ser um ensaio simples e rápido na caracterização de materiais [Pinho, 2003], que permite estimar o valor da resistência à compressão uniaxial dos planos das descontinuidades do maciço rochoso (JCS), nos diferentes locais de amostragem. O parâmetro JCS, o coeficiente de rugosidade da descontinuidade (JRC) e a tensão efectiva normal (’n ), foram necessários para obter o ângulo de atrito das diaclases (Øpico), de acordo com o método proposto pela Sociedade Internacional de Mecânica das Rochas [ISRM, 1978]. O estudo realizado permitiu concluir que o maciço apresenta boa qualidade, em regra, homogénea relativamente às suas características geológicas e geotécnicas. No entanto, distinguem-se duas zonas, ZG1 e ZG2, com base em pequenas diferenças nos valores da resistência à compressão uniaxial da rocha e do ângulo de atrito das fraturas

A neural network underlying cognitive strategies related to eating, weight and body image concerns

Concerns about food intake, weight and body shape can trigger negatively loaded emotions, which may prompt the use of cognitive strategies to regulate these emotional states. A novel fMRI task was developed to assess the neurobehavioral correlates of cognitive strategies related to eating, weight and body image concerns, such as self-criticism, avoidance, rumination, and self-reassurance. Fourteen healthy females were presented audio sentences referring to these conditions and instructed to repeat these internally while engaging their thoughts with the content of food or body images. Participants were asked to report the elicited emotion and rate their performance. All cognitive strategies recruited a network including the inferior and superior frontal gyri, orbitofrontal and anterior cingulate cortex, insula, and dorsal striatum. These brain regions are involved in emotional, reward and inhibitory control processing. Representational similarity analysis revealed distinct patterns of neural responses for each cognitive strategy. Additionally, self-report measures showed that self-criticism was positively associated with superior frontal gyrus (SFG) activation. Self-compassion scores were negatively correlated with activations in the insula and right putamen, while self-reassurance scores were negatively associated with activity in the orbitofrontal cortex. These findings identify a neural network underlying cognitive strategies related to eating, weight and body image concerns, where neurobehavioral correlation patterns depend on the cognitive strategy