72 research outputs found
Novel heterococcolithophores, holococcolithophores and life cycle combinations from the families Syracosphaeraceae and Papposphaeraceae and the genus Florisphaera
Abstract. Coccolithophores are a diverse group of calcifying phytoplankton, which are responsible for a large part of the modern oceanic carbonate production. Here, we describe novel or poorly known coccolithophores and novel life cycle combination coccospheres detected in samples collected either in the Gulf of Aqaba in the northern Red Sea or in the Gulf of Naples in the western Mediterranean. These include Syracosphaera winteri, for which detached coccoliths have previously been recorded but both a formal description and taxonomic affiliation were lacking, and five undescribed sets of combination cells linking HET and HOL forms for S. pulchra, S. mediterranea, S. azureaplaneta, S. lamina and S. orbicula. We also propose the replacement name S. kareniae for the fossil species Deutschlandia gaarderae. We describe a new species of the genus Ophiaster, O. macrospinus, displaying a unique morphological and ecological distribution as well as putative combination cells of two variants of the deep-dwelling Florisphaera profunda, which provide new insights on the affiliation of this genus within the Calcihaptophycideae. Additionally, in the family Papposphaeraceae we detected a new species, Pappomonas vexillata, and combination cells of Picarola margalefi and of a species resembling Papposphaera arctica. Finally, we detected three novel, unpaired holococcolithophore forms (Calyptrosphaera lluisae, Calicasphaera bipora and one form designated as Holococcolithophore A). Overall, this set of novel observations and ensuing discussions provide further insights into the diversity, evolution and life cycle complexity of coccolithophores in the oceans
Long-term follow-up of dorsal wedge osteotomy for pediatric freiberg disease
Background: Treatment for Freiberg disease has been largely conservative despite availability of various operative options for severe or refractory cases. The aim of this study was to evaluate the long-term results of pediatric patients with symptomatic Freiberg disease treated with intra-articular dorsal wedge osteotomy.
Methods: Pediatric patients treated for Freiberg disease with surgery between January 1982 and 1999 were identified and selected for long-term clinical evaluation. Patients were evaluated regarding operative satisfaction and clinical outcome, performed according to the American Orthopaedic Foot & Ankle Society (AOFAS) lesser toe metatarsophalangeal-interphalangeal scale and range of motion (ROM) of metatarsophalangeal (MTP) joint. Patients had radiographic assessment of degenerative joint status with anteroposterior and oblique foot x-ray. Twenty patients (18 female, 2 male; mean age 15.2 years; range 12-17 years) were identified. The mean follow-up period was 23.4 (range 15-32) years.
Results: The clinical outcomes of our patients were classified as excellent in 16 (80%) and good in 4 (20%). The AOFAS mean score was 96.8 (range 91-100) points at the last clinical appointment. A negative correlation between AOFAS score and time of follow-up (r's = -0.61, P < .001) was found. Also, a strong negative correlation was found between Smillie classification and AOFAS final score (r's = -0.88, P < .001).
Conclusion: The patients were very satisfied with pain and quality of life at a mean follow-up time of 23.4 years. To our knowledge, this is the first long-term follow-up report supporting the procedure described by Gauthier and Elbaz as a good option for operative treatment of Freiberg disease.info:eu-repo/semantics/publishedVersio
A molecular insight into algal-oomycete warfare : cDNA analysis of Ectocarpus siliculosus infected with the basal oomycete Eurychasma dicksonii
Peer reviewedPublisher PD
Anesthesiology Consensus in the Management of the Airway
Os consensos na gestão clínica da via aérea em anestesiologia pretendem disponibilizar informação, baseada na evidência atual ou, na falta desta, na opinião de peritos, no que respeita à abordagem da via aérea difícil previsível ou não previsível.
Reforçamos a importância da avaliação da via aérea e da identificação de potenciais problemas que possam condicionar dificuldade na sua abordagem e a adoção de uma estratégia segura que permita identificar e responder em crescendo de intervenção às dificuldades encontradas. Na impossibilidade de intubação traqueal (não intubo) otimizada e limitada a 4 tentativas, da impossibilidade de ventilar e oxigenar (não oxigeno) após 2 tentativas de usar um dispositivo supraglótico ou de uso de máscara facial inicialmente adequada é importante realizar, em tempo útil, uma cricotirotomia para assegurar oxigenação.
As situações clínicas de exceção só com planos simples, conhecidos por todos e regularmente treinados e adaptados à nossa atividade clinica podem assegurar melhores “outcomes”.
O registo destes eventos e a informação ao nosso doente da dificuldade encontrada e modo como foi resolvido o problema é essencial e constitui ainda um desafio a alargar a uma base nacional.info:eu-repo/semantics/publishedVersio
Assessment of sense of taste in Italian Centenarians
The Italian multicentric study on centenarians (IMSC) was aimed at assessing the level of preservation of the sense of taste, and at estimating to what extent the recognition of various gustative stimuli can give satisfaction and information regarding the surrounding environment for the centenarians. Taste sensitivity has been qualitatively established in a group of 126 Italian centenarians (mean age 101.9 \ub1 1.4 years) and compared to that of a group of 100 elderly subjects (mean age 70.5 \ub1 5.0 years). All the individuals included in the study groups had a mini mental state examination (MMSE) score larger than 19. The results revealed that taste sensitivity is significantly reduced in the centenarians; as a matter of fact, the elderly control subjects are able to perceive taste stimuli in 84.25 \ub1 3.40% of the testing, while the centenarians were successful only in 74.23 \ub1 6.19% of the experiments (P < 0.001). Furthermore, elderly subjects can correctly recognize taste stimuli in 70% of the testings, while correct recognition amounted only to 49.25% in cases of centenarians assessed. In spite of these differences between the elderly and centenarians, the latter are still able to perceive and recognize taste stimuli adequately, and as a consequence, are able to obtain information on tastes and receive a sufficient sensory stimulation through the tasting pathway
Ocean acidification has different effects on the production of dimethylsulfide and dimethylsulfoniopropionate measured in cultures of Emiliania huxleyi and a mesocosm study:a comparison of laboratory monocultures and community interactions
The human-induced rise in atmospheric carbon dioxide since the industrial revolution has led to increasing oceanic carbon uptake and changes in seawater carbonate chemistry, resulting in lowering of surface water pH. In this study we investigated the effect of increasing CO2 partial pressure (pCO2) on concentrations of volatile biogenic dimethylsulfide (DMS) and its precursor dimethylsulfoniopropionate (DMSP), through monoculture studies and community pCO2 perturbation. DMS is a climatically important gas produced by many marine algae: it transfers sulfur into the atmosphere and is a major influence on biogeochemical climate regulation through breakdown to sulfate and formation of subsequent cloud condensation nuclei (CCN). Overall, production of DMS and DMSP by the coccolithophore Emiliania huxleyi strain RCC1229 was unaffected by growth at 900 μatm pCO2, but DMSP production normalised to cell volume was 12 % lower at the higher pCO2 treatment. These cultures were compared with community DMS and DMSP production during an elevated pCO2 mesocosm experiment with the aim of studying E. huxleyi in the natural environment. Results contrasted with the culture experiments and showed reductions in community DMS and DMSP concentrations of up to 60 and 32 % respectively at pCO2 up to 3000 μatm, with changes attributed to poorer growth of DMSP-producing nanophytoplankton species, including E. huxleyi, and potentially increased microbial consumption of DMS and dissolved DMSP at higher pCO2. DMS and DMSP production differences between culture and community likely arise from pH affecting the inter-species responses between microbial producers and consumers
Nitric oxide production and antioxidant function during viral infection of the coccolithophore Emiliania huxleyi
Emiliania huxleyi is a globally important marine phytoplankton that is routinely infected by viruses. Understanding the controls on the growth and demise of E. huxleyi blooms is essential for predicting the biogeochemical fate of their organic carbon and nutrients. In this study, we show that the production of nitric oxide (NO), a gaseous, membrane-permeable free radical, is a hallmark of early-stage lytic infection in E. huxleyi by Coccolithoviruses, both in culture and in natural populations in the North Atlantic. Enhanced NO production was detected both intra- and extra-cellularly in laboratory cultures, and treatment of cells with an NO scavenger significantly reduced viral production. Pre-treatment of exponentially growing E. huxleyi cultures with the NO donor S-nitroso-N-acetylpenicillamine (SNAP) prior to challenge with hydrogen peroxide (H2O2) led to greater cell survival, suggesting that NO may have a cellular antioxidant function. Indeed, cell lysates generated from cultures treated with SNAP and undergoing infection displayed enhanced ability to detoxify H2O2. Lastly, we show that fluorescent indicators of cellular ROS, NO, and death, in combination with classic DNA- and lipid-based biomarkers of infection, can function as real-time diagnostic tools to identify and contextualize viral infection in natural E. huxleyi blooms
Articulating knowledge work: the contributions of Activity Theory and task-based knowledge management
This chapter addresses issues of knowledge work in organisations with a concern that mainstream knowledge management (KM) has fallen short of expectations. The real nature of knowledge work remains hidden, and thus inaccessible, to those who are trying to improve organisational outcomes through KM practices. The authors have conducted independent research within a new discourse on knowledge work in the context of modem complex organisations, the results of which are converging to a common understanding of this critical phenomenon. Their two theoretical frameworks, one task-based and one activity-based, are described here as eminently suited to this research. Two sets of selected published work, each using one of the approaches, are compared using a content analysis tool and the findings are analysed to identify common concepts
The role of knowledge management governance in the implementation of strategy
Previous research has examined different understandings of the concept of knowledge management and from this, a multiplicity of approaches to implement strategies have been derived. This paper presents research that examines the role of governance as a framework to ensure the effective delivery of a knowledge management strategy. Knowledge management governance is considered and a conceptual framework developed to appropriately position knowledge management governance within the organization. It draws on the results of research into knowledge management governance practices in a major scientific research facility and those in a confectionary manufacturer. We conclude that the implementation of a knowledge management strategy through such a framework ensures the delivery of anticipated benefits in an authorized and regulated manner
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