162 research outputs found

    Effects of Increasing Seawater Carbon Dioxide Concentrations on Chain Formation of the Diatom Asterionellopsis glacialis

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    Diatoms can occur as single cells or as chain-forming aggregates. These two strategies affect buoyancy, predator evasion, light absorption and nutrient uptake. Adjacent cells in chains establish connections through various processes that determine strength and flexibility of the bonds, and at distinct cellular locations defining colony structure. Chain length has been found to vary with temperature and nutrient availability as well as being positively correlated with growth rate. However, the potential effect of enhanced carbon dioxide (CO2) concentrations and consequent changes in seawater carbonate chemistry on chain formation is virtually unknown. Here we report on experiments with semi-continuous cultures of the freshly isolated diatom Asterionellopsis glacialis grown under increasing CO2 levels ranging from 320 to 3400 mu atm. We show that the number of cells comprising a chain, and therefore chain length, increases with rising CO2 concentrations. We also demonstrate that while cell division rate changes with CO2 concentrations, carbon, nitrogen and phosphorus cellular quotas vary proportionally, evident by unchanged organic matter ratios. Finally, beyond the optimum CO2 concentration for growth, carbon allocation changes from cellular storage to increased exudation of dissolved organic carbon. The observed structural adjustment in colony size could enable growth at high CO2 levels, since longer, spiral-shaped chains are likely to create microclimates with higher pH during the light period. Moreover increased chain length of Asterionellopsis glacialis may influence buoyancy and, consequently, affect competitive fitness as well as sinking rates. This would potentially impact the delicate balance between the microbial loop and export of organic matter, with consequences for atmospheric carbon dioxide

    The drivers of plant turnover change across spatial scales in the Azores

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    Beta diversity patterns are essential for understanding how biological communities are structured. Geographical and environmental factors, as well as species dispersal ability, are important drivers of beta diversity, but their relative importance may vary across spatial scales. In this study, we evaluate whether beta diversity changes across geographical scales and analyse how different drivers affect turnover patterns of native seed plants in an oceanic archipelago, the Azores (Portugal). Using a 500 × 500 m resolution grid, we selected cells that are covered by one of the following habitats: native forest, naturalized vegetation and seminatural pastures. We calculated species turnover at three spatial scales: 1) between islands, 2) between cells within each island, and finally 3) between cells of each of the habitats of interest in each island. We then calculated the contribution of dispersal syndromes (endozoochory, epizoochory, hydrochory and anemochory) to turnover at each of the scales. Lastly, we assessed the relationship between geographical and climatic distances and habitat type with turnover. Turnover was higher at the smallest spatial scale, particularly in seminatural pastures, and decreased with increasing spatial scales, a pattern potentially associated with the historical fragmentation and current patchy distribution of native forest and seminatural habitats in the Azores. Dispersal syndromes and habitat type had a negligible effect on turnover at all scales. Geographical distance had a positive effect on turnover at all scales, increasing its importance with scale. The relationship between turnover and climatic distance was only significant at the intermediate and small scales in specific islands and habitats. Therefore, scale plays an important role at determining the effect of the drivers of turnover, in particular geographical and climatic distance. These results highlight the need to carefully select the scale of analysis when studying turnover patterns, as well as identifying the potential drivers associated with each spatial scale.info:eu-repo/semantics/publishedVersio

    Implications of climate change to the design of protected areas : The case study of small islands (Azores)

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    Climate change is causing shifts in species distributions worldwide. Understanding how species distributions will change with future climate change is thus critical for conservation planning. Impacts on oceanic islands are potentially major given the disproportionate number of endemic species and the consequent risk that local extinctions might become global ones. In this study, we use species climate envelope models to evaluate the current and future potential distributions of Azorean endemic species of bryophytes, vascular plants, and arthropods on the Islands of Terceira and Sao Miguel in the Azores archipelago (Macaronesia). We examined projections of climate change effects on the future distributions of species with particular focus on the current protected areas. We then used spatial planning optimization software (PRION) to evaluate the effectiveness of protected areas at preserving species both in the present and future. We found that contractions of species distributions in protected areas are more likely in the largest and most populated island of Sao Miguel, moving from the coastal areas towards inland where the current protected areas are insufficient and inadequate to tackle species distribution shifts. There will be the need for a revision of the current protected areas in Sao Miguel to allow the sustainable conservation of most species, while in Terceira Island the current protected areas appear to be sufficient. Our study demonstrates the importance of these tools for informing long-term climate change adaptation planning for small islands.Peer reviewe

    Short Mood and Feelings Questionnaire for screening children and adolescents for plastic surgery: cross-cultural validation study

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    CONTEXT AND OBJECTIVE: Patient-reported outcome measurements assessing the emotional state of children and adolescents who seek plastic surgery are important for determining whether the intervention is indicated or not. The aim of this study was to cross-culturally adapt and validate the Short Mood and Feelings Questionnaire (child/adolescent and parent versions) for Brazilian Portuguese, test its psychometric properties and assess the emotional state of children and adolescents who seek plastic surgery. DESIGN AND SETTING: Cross-cultural validation study conducted in a plastic surgery outpatient clinic at a public university hospital. METHODS: A total of 124 consecutive patients of both sexes were selected between September 2013 and February 2014. Forty-seven patients participated in the cultural adaptation of the questionnaire. The final version was tested for reliability on 20 patients. Construct validity was tested on 57 patients by correlating the Short Mood and Feelings Questionnaire (child/adolescent and parent versions) with the Strengths and Difficulties Questionnaire and the Rosenberg Self-Esteem scale. RESULTS: The child/adolescent and parent versions of the Short Mood and Feelings Questionnaire showed Cronbach's alpha of 0.768 and 0.874, respectively, and had good inter-rater reliability (intraclass correlation coefficient, ICC = 0.757 and ICC = 0.853, respectively) and intra-rater reliability (ICC = 0.738 and ICC = 0.796, respectively). CONCLUSIONS: The Brazilian-Portuguese version of the Short Mood and Feelings Questionnaire is a reproducible instrument with face, content and construct validity. The mood state and feelings among children and adolescents seeking cosmetic surgery were healthy.Univ Fed Sao Paulo UNIFESP, Dept Surg, Div Plast Surg, Sao Paulo, SP, BrazilUniv Fed Sao Paulo UNIFESP, Postgrad Program Translat Surg, Sao Paulo, SP, BrazilInst Fed Educ Ciencia & Tecnol Sul Minas IFSuldeM, Pouso Alegre, MG, BrazilUniv Vale do Sapucai UNIVAS, Coll Hlth Sci, Pouso Alegre, SP, BrazilUniv Fed Sao Paulo UNIFESP, Dept Surg, Div Plast Surg, Sao Paulo, SP, BrazilUniv Fed Sao Paulo UNIFESP, Postgrad Program Translat Surg, Sao Paulo, SP, BrazilWeb of Scienc

    Comparison between two shock wave regimens using frequencies of 60 and 90 impulses per minute for urinary stones

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    PURPOSE: Two different regimens of SWL delivery for treating urinary stones were compared. METHODS: Patients with urinary stones were randomly divided into two groups, one of which received 3000 shocks at a rate of 60 impulses per minute and the other of which received 4000 shocks at 90 impulses per minute. Success was defined as stone-free status or the detection of residual fragments of less than or equal to 3 mm three months after treatment. Partial fragmentation was considered to have occurred if a significant reduction in the stone burden was observed but residual fragments of 3mm or greater remained. RESULTS: A total of 143 procedures were performed with 3000 impulses at a rate of 60 impulses per minute, and 156 procedures were performed with 4000 impulses at 90 impulses per minute. The stone-free rate was 53.1% for patients treated with the first regimen and 54.8% for those treated with the second one (p = 0.603). The stone-free rate for stones smaller than 10 mm was 60% for patients treated with 60 impulses per minute and 58.6% for those treated with 90 impulses per minute. For stones bigger than 10 mm, stone-free rates were 34.2% and 45.7%, respectively (p = 0.483). Complications occurred in 2.3% of patients treated with 60 impulses per minute and 3.3% of patients treated with 90 impulses per minute. CONCLUSION: No significant differences in the stone-free and complication rates were observed by reducing the total number of impulses from 4000 to 3000 and the frequency from 90 to 60 impulses per minute

    Coeficiente de repetibilidade para a determinação do número ótimo de colheitas para seleção de abobrinha-italiana

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    The objective of this work was to estimate the optimal number of harvests for the reliable selection of zucchini (Cucurbita pepo) hybrids through the repeatability coefficient. The experimental design was randomized complete blocks with 33 treatments (31 experimental hybrids and 2 commercial ones) and four replicates, with six plants per plot. Fifteen harvests were carried out. Seven morphoagronomic fruit characteristics were evaluated, and repeatability coefficients were estimated using four statistical methods. The repeatability coefficients ranged from low to moderate, regardless of the studied characteristic. For a high-precision selection (R2≥90%), a high number of evaluated harvests was required, especially for traits related to fruit yield, as follows: 30 to 54 harvests for selection based on total yield; and 43 to 83 harvests for commercial yield, which varied according to the statistical estimation method. The principal component analysis based on the covariance matrix required the least number of harvests for a satisfactory selection precision. Fifteen harvests are sufficient for a satisfactory selection of all evaluated characteristics, with a precision above 70%.O objetivo deste trabalho foi estimar o número ótimo de colheitas para a seleção confiável de híbridos de abobrinha-italiana (Cucurbita pepo) por meio do coeficiente de repetibilidade. O delineamento experimental foi em blocos ao acaso, com 33 tratamentos (31 híbridos experimentais e 2 comerciais) e quatro repetições, com seis plantas por parcela. Realizaram-se 15 colheitas. Sete características morfoagronômicas dos frutos foram avaliadas, e os coeficientes de repetibilidade foram estimados por meio de quatro métodos estatísticos. Os coeficientes de repetibilidade variaram de baixos a moderados, independentemente da característica estudada. Para uma seleção de alta precisão (R2≥90%), um elevado número de colheitas avaliadas foi necessário, especialmente para as características relacionadas à produtividade de frutos, conforme a seguir: 30 a 54 colheitas para a seleção baseada na produtividade total; e 43 a 83 colheitas para a produtividade comercial, que variou conforme o método estatístico de estimação. A análise de componentes principais baseada na matriz de covariância demandou a menor quantidade de colheitas para uma precisão satisfatória da seleção. São suficientes 15 colheitas para a seleção satisfatória de todas as características avaliadas, com precisão superior a 70%

    Exequibilidade, segurança e utilidade da biópsia endomiocárdica ventricular esquerda por acesso transradial : experiência inicial de um centro universitário terciário

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    © 2020 Sociedade Portuguesa de Cardiologia. Published by Elsevier España, S.L.U. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/bync-nd/4.0/).Introduction and objectives: Over the last decade, several studies have suggested that left ventricular endomyocardial biopsy is safer and has a higher diagnostic yield than transvenous right ventricular biopsy. In addition, recent publications indicate that the transradial approach is a feasible and safe alternative to the transfemoral approach for sampling the left ventricle. We report our initial experience with transradial endomyocardial biopsy with regards to feasibility, safety and usefulness. Methods: Single-center registry of consecutive patients undergoing intended transradial left endomyocardial biopsy. Clinical and technical data were collected prospectively, with a particular focus on success rate and complications. Results: Twenty-seven patients were screened for left ventricle biopsy. Twenty (25) were selected for an intended transradial approach (mean age 51±18 years old, 22 male). Success rate was 100% with no crossover to femoral approach. There were no major complications. Two patients experienced mild radial spasm. One of them also had a run of non-sustained ventricular tachycardia. Indication for biopsy was either myocarditis or cardiomyopathy of unknown etiology. The final diagnosis was acute lymphocytic myocarditis in five patients, chronic myocarditis in one patient, amyloid light-chain amyloidosis in four patients and transthyretin amyloidosis in six patients. Myocarditis was ruled out in eight patients and amyloidosis in one patient. Conclusions: Transradial left ventricle endomyocardial biopsy is a very safe and feasible method of sampling the myocardium for histopathological analysis, with a good diagnostic yield and clinically meaningful results in properly selected patients.info:eu-repo/semantics/publishedVersio

    Los riesgos de las lluvias torrenciales en las islas de la Macaronesia (Azores, Madeira, Canarias y Cabo Verde)

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    Ponencia presentada en: V Congreso Internacional de la Asociación Española de Climatología celebrado en Zaragoza del 18 al 21 de septiembre de 2006.[ES]En este artículo se realiza un análisis comparativo de las precipitaciones diarias de las islas de Terceira (Azores), Madeira (Madeira), Tenerife (Canarias) y Santiago (Cabo Verde) con el fin de caracterizar la pluviosidad en los cuatro archipiélagos de la Macaronesia. Se examinan así mismo los episodios diarios de lluvias más intensas, su duración y frecuencia, para determinar la vulnerabilidad de esos archipiélagos ante fenómenos meteorológicos extremos de ese tipo.[EN]In this article there is realized a comparative analysis of the daily rainfalls of the islands of Terceira, Madeira, Tenerife and Santiago in order to characterize the rainfall in the four archipelagoes of the Macaronesia. There are examined likewise the daily episodes of the most intense rains, its duration and frequency, to determine the vulnerability of these archipelagoes before meteorological extreme phenomena of this type.Este estudio se realiza con fondos FEDER del proyecto de investigación Modelización climática de islas montañosas subtropicales: Tenerife CLIMAAT Y CLIMAAT II (INTERREG III-B) MAC 2.3/A.3 y 03/MAC 2.3/A.5

    Influence of fertilizer and hydrogel on physical-chemical attributes of substrate for seedling production

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    The incorporation of the hydrogel into the substrate used in the forest nursery promotes improvements in its physical-chemical attributes. However, several factors influence the hydrogel efficiency, such as the increase of salts, promoted by fertilizer of the substrate. Therefore, this study aimed to evaluate the effects of the incorporation of fertilizer levels and hydrogel doses on the physical-chemical attributes of a substrate to produce forest seedlings. Different levels of basic fertilizer commonly used in the nursery (100%, 50% and 0%) and different doses of the hydrogel (0, 1, 2 and 3 g L-1) were incorporated into the substrate Tropstrato Florestal®, consisting of 12 treatments in a 3 x 4 factorial scheme. A sample of the substrate in each treatment was sent for analysis of its physical and chemical attributes. To evaluate the effect of the treatments on the physical-chemical attributes of the substrate, was used the multivariate principal components analyses. The levels of fertilizer and hydrogel doses were correlated with the attributes of the substrates obtained in each treatment. The incorporation of different fertilizer levels and hydrogel doses to the substrate modified their chemical and physical attributes. Fertilizers have influenced mainly the chemical attributes of the substrate, whereas hydrogels have influenced the physical attributes, mainly those related to water retention capacity and availability

    A Rapid and Sensitive Single Residual Method for Determination of Ethephon in Grape by high performance liquid chromatography-tandem mass spectrometry/ Um método residual rápido e sensível para a determinação de Ethephon em uvas por cromatografia líquida de alta eficiência e espectrometria de massa em tandem

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    This paper describes a rapid (7.0 min) and sensitive (LLOQ 0.1 ng/mL) analytical method for the quantitation of Ethephon  in grape.  A new method for the detection and quantification of ETP residues in fruit and vegetables was developed. The present study indicates that fruit and vegetables require a rapid and simple cleanup step before using gas chromatograph/mass spectrometry. The recovery and precision of the new method were evaluated by spiking the fruit and vegetable samples with 0.01-0.1 μg/g of ETP. The method is based on High-performance Liquid chromatography-tandem mass spectrometry (LC-MS/MS).The chromatographic separation was achieved on a Hypercarb 2.1x 100 mm 5µm reversed-phase column and a mobile phase containing water/mathanol (97:3 v/v, add 1% acetic acid), in isocratic conditions. The target analytes were transferred into a triple quadrupole mass spectrometer equipped with an electrospray ionization source for mass detection. The ion transitions selected for MRM detection were:  m/z 142.8 106.8, m/z 144.8 106.8 and 106.878.8 for ETP. The linearity of the detector response was demonstrated in the range from 0.01 to 1 µg/g for each analyte with a coefficient of determination (R2) of ≥0.999. The method was successfully applied to determination of ethephon in bunch grapes from five free trade fairs in the city of Caruaru, Pernambuco, Brazil
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