188 research outputs found

    A new deep sea coralline sponge from Turks and Caicos Islands: <i>Willardia caicosensis</i> gen. <i>et</i> sp. nov. (Demospongiae: Hadromerida)

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    A new coralline sponge, Willardia caicosensis, assigned to the family Timeidae, is described from the deep fore reef off the Turks & Caicos Islands, tropical western Atlantic Ocean, where it is common at depths ranging from 100 to 119 m. Individuals vary up to 15-20 cm in width. The relatively thin aragonitic skeleton is covered with delicate pillars up to + 1 mm. The living tissue is restricted to the spaces between pillars and a thin sheet lying above the calcareous skeleton. Exhalant canals converge upon regularly spaced central oscules on the sponge surface. Siliceous spicules include tylostyles and amphiasters which are secondarily embedded in the aragonitic moiety of the skeleton. In addition, ultrastructural characters of thechoanocytes, such as periflagellar sleeves are typical of the Order Hadromerida. Two types of cells with dense spherules are abundant in the mesohyl: sperulous cells packed with large heterogeneous inclusions, protruding at the surface of the sponge, and glycocytes with smaller ovoid corpuscles, mainly grouped along the basal calcareous skeleton. Rough collagen fibrils extend in tracts from the base of the sponge to the ectosome. Sparse bacteria are scattered in the mesohyl

    Façade refurbishment of existing office buildings: Do conventional energy-saving interventions always work?

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    Offices account for 40% of energy use in construction sector. Office building stock is already under-performing and dilapidating at a fast pace. With the current rate of replacing old building stock in the UK, it is expected that at least 60% of what was built before 1985 still exists in 2050. Therefore, refurbishment, with an aim to improve performance of buildings, seems to remain as the most feasible and arguably most cost efficient way forward. Precedent studies in this area are not few and far between. However, some recommendations and interventions seems to have been taken for granted and thought to be globally applicable almost everywhere. This study chooses a recently refurbished office building to challenge this common belief. It was shown that, from the carbon point of view, benefits as a result of interventions were marginal. It was found that a full pre-refurbishment survey, measures aimed at reducing the performance gap between intended and actual figures, and study of occupancy patterns would probably help in this respect. The study results also showed that study of contextual conditions i.e. careful considerations with regards to building orientation, topography, site constraints, and exposure to solar gains will help achieve better results. Finally it was envisaged that better user engagement, communication and using few other measures to enhance user satisfaction will help guarantee some other aspects pertaining to performance than its mere energy consumption or carbon footprint

    Urban Heat Island (UHI) mitigating strategies: A case-based comparative analysis

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    Urbanisation may have been shown to have no effect on climate change, but some researchers suggest that cities are fully capable of responding to it. Urban Heat Islands (UHIs) represent dense urban areas within cities where the temperature is recorded to be higher than the neighbouring areas or those located in suburbia. Mitigation of UHI effects can help diminish detriments of climate change. This paper sets out to establish UHI mitigation strategies, their effectiveness and resilience to help provide recommendations for application of such strategies in future. Existing literature suggest that UK is facing with growing problem of UHI effects and sustainable development at urban scale can be improved if proportionate measures are taken to mitigate those effects. The lack of guidance for designers and planners with regards to UHI mitigation is also indicated in the literature where trees, shrubs and grass (TSG), use of high albedo materials (HAM) in external building surfaces and urban inland water bodies (UIWB) are identified as effective measures to mitigate UHI. This research identifies and tests resilience and effectiveness of UHI mitigation strategies, using ENVI-met simulations and through Urban Futures Assessment Method (UFAM). Assessed mitigation strategies (TSG, HAM, UIWB) are shown to have a similar level of resilience which could be improved if proper future-proof measures are taken in place. As a result, some practical suggestions are provided to help improve the resilience of tested UHI mitigation strategies in this study

    Differential modulation of microglia superoxide anion and thromboxane B(2 )generation by the marine manzamines

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    BACKGROUND: Thromboxane B(2 )(TXB(2)) and superoxide anion (O(2)(-)) are neuroinflammatory mediators that appear to be involved in the pathogenesis of several neurodegenerative diseases. Because activated-microglia are the main source of TXB(2 )and O(2)(- )in these disorders, modulation of their synthesis has been hypothesized as a potential therapeutic approach for neuroinflammatory disorders. Marine natural products have become a source of novel agents that modulate eicosanoids and O(2)(- )generation from activated murine and human leukocytes. With the exception of manzamine C, all other manzamines tested are characterized by a complex pentacyclic diamine linked to C-1 of the β-carboline moiety. These marine-derived alkaloids have been reported to possess a diverse range of bioactivities including anticancer, immunostimulatory, insecticidal, antibacterial, antimalarial and antituberculosis activities. The purpose of this investigation was to conduct a structure-activity relationship study with manzamines (MZ) A, B, C, D, E and F on agonist-stimulated release of TXB(2 )and O(2)(- )from E. coli LPS-activated rat neonatal microglia in vitro. RESULTS: The manzamines differentially attenuated PMA (phorbol 12-myristate 13-acetate)-stimulated TXB(2 )generation in the following order of decreasing potency: MZA (IC(50 )<0.016 μM) >MZD (IC(50 )= 0.23 μM) >MZB (IC(50 )= 1.6 μM) >MZC (IC(50 )= 2.98 μM) >MZE and F (IC(50 )>10 μM). In contrast, there was less effect on OPZ (opsonized zymosan)-stimulated TXB(2 )generation: MZB (IC(50 )= 1.44 μM) >MZA (IC(50 )= 3.16 μM) >MZC (IC(50 )= 3.34 μM) >MZD, MZE and MZF (IC(50 )>10 μM). Similarly, PMA-stimulated O(2)(- )generation was affected differentially as follows: MZD (apparent IC(50)<0.1 μM) >MZA (IC(50 )= 0.1 μM) >MZB (IC(50 )= 3.16 μM) >MZC (IC(50 )= 3.43 μM) >MZE and MZF (IC(50 )>10 μM). In contrast, OPZ-stimulated O(2)(- )generation was minimally affected: MZB (IC(50 )= 4.17 μM) >MZC (IC(50 )= 9.3 μM) >MZA, MZD, MZE and MZF (IC(50 )> 10 μM). From the structure-activity relationship perspective, contributing factors to the observed differential bioactivity on TXB(2 )and O(2)(- )generation are the solubility or ionic forms of MZA and D as well as changes such as saturation or oxidation of the β carboline or 8-membered amine ring. In contrast, the fused 13-membered macrocyclic and isoquinoline ring system, and any substitutions in these rings would not appear to be factors contributing to bioactivity. CONCLUSION: To our knowledge, this is the first experimental study that demonstrates that MZA, at in vitro concentrations that are non toxic to E. coli LPS-activated rat neonatal microglia, potently modulates PMA-stimulated TXB(2 )and O(2)(- )generation. MZA may thus be a lead candidate for the development of novel therapeutic agents for the modulation of TXB(2 )and O(2)(- )release in neuroinflammatory diseases. Marine natural products provide a novel and rich source of chemical diversity that can contribute to the design and development of new and potentially useful anti-inflammatory agents to treat neurodegenerative diseases

    Energy performance of Double-Skin Façades in temperate climates: A systematic review and meta-analysis

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    Double Skin Façades (DSFs) are applied in both new and existing buildings, especially in temperate climates. Research in this area is steadily growing; however, there is a lack of conclusive results in available literature about energy performances related to the DSF, thus limiting a better and more informed application of this technology in the Architecture Engineering and Construction (AEC) sector. This article systematically reviews more than 50 articles which have dealt with the energy related performance of DSFs in temperate climates and provide a meta-analysis of the numerical findings published in the studies examined. Energy related figures are presented separately for embodied and operational energy. Specifically, the operational energy end-uses taken into account are heating, cooling, lighting, and ventilation. Numerical results in the literature are normalised and expressed in form of percentage of maximum energy reduction/increment compared to a base case (e.g. a single skin case) used as a reference in the corresponding studies. Such an approach is meant to provide a reliable comparison of published figures. Key façade parameters (DSF spatial configurations, cavity width and ventilation), building parameters (orientation and climatic areas) and the methodological approaches used in the reviewed studies were adopted as clustering criteria. Several clustering criteria present extremely spread values, indicating the necessity to further investigate, understand, and attempt to reduce such high discrepancies in operational energy performances. Additionally, and more importantly, almost no information exists on DSFs life cycle energy figures, highlighting an important gap that requires further research

    Life cycle energy and carbon assessment of double skin façades for office refurbishments

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    In countries like the UK, the upkeep of existing buildings is where the greatest opportunities for achieving carbon reduction targets lie. Façades are the physical barriers between outdoors and indoors, and their upgrade can arguably be amongst the most effective interventions to improve the existing stock. Double Skin Façades (DSFs) represent a possible solution for low-carbon refurbishment due to their capability to reduce energy consumption, and the related carbon emissions, of the building they are applied to. Although much research exists on maximising the operational energy savings of DSFs, little is known about their life cycle performance. This article addresses such a knowledge gap through a comparative life cycle assessment between DSF refurbishments and an up-to-standard, single-skin alternative. This study adopts a parametric approach where 128 DSF configurations have been analysed through primary data. Energy and carbon (both operational and embodied) are the units assessed in this research. Results show that DSFs are more energy-efficient than single-skin in 98% of the cases, and more carbon-efficient in 85% of the cases. Not only does this study represent the first broad parametric approach to evaluating life cycle energy and carbon of DSFs within its given context, but it also informs environmentally-aware design and application of DSFs

    PTPN11 mutations are not responsible for the Cardiofaciocutaneous (CFC) syndrome

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    Cardiofaciocutaneous (CFC) syndrome is a multiple congenital anomalies/mental retardation syndrome characterized by congenital heart defects, characteristic facial appearance, short stature, ectodermal abnormalities and mental retardation. It was described in 1986, and to date is of unknown genetic etiology. All reported cases are sporadic, born to non-consanguineous parents and have apparently normal chromosomes. Noonan and Costello syndromes remain its main differential diagnosis. the recent finding of PTPN11 missense mutations in 45-50% of the Noonan patients studied with penetrance of almost 100% and the fact that in animals mutations of this gene cause defects of semilunar valvulogenesis, made PTPN11 mutation screening in CFC patients a matter of interest. We sequenced the entire coding region of the PTPN11 gene in ten well-characterised CFC patients and found no base changes. We also studied PTPN11 cDNA in our patients and demonstrated that there are no interstitial deletions either. the genetic cause of CFC syndrome remains unknown, and PTPN11 can be reasonably excluded as a candidate gene for the CFC syndrome, which we regard as molecular evidence that CFC and Noonan syndromes are distinct genetic entities.Univ Sacred Heart, Ist Genet Med, I-00168 Rome, ItalyUniversidade Federal de São Paulo, Escola Paulista Med, Ctr Med Genet, São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Dermatol, São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Ctr Med Genet, São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Dermatol, São Paulo, BrazilWeb of Scienc

    Investigating relationships between cost and CO<sub>2</sub> emissions in reinforced concrete structures using a BIM-based design optimisation approach

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    An integrated design approach for the cost and embodied carbon optimisation of reinforced concrete structures is presented in this paper to inform early design decisions. A BIM-based optimisation approach that utilises Finite Element Modelling (FEM) and a multi-objective genetic algorithm with constructability constraints is established for that purpose. A multilevel engineering analysis model is developed to perform structural layout optimisation, slab and columns sizing optimisation, and slab and columns reinforcement optimisation. The overall approach is validated using real buildings and the relationships between cost and carbon optimum solutions are explored. The study exhibits how cost effective and carbon efficient solutions could be obtained without compromising the feasibility of the optimised designs. Results demonstrate that the structural layout and the slab thickness are amongst the most important design optimisation parameters. Finally, the overall analysis suggests that the building form can influence the relationships between cost and carbon for the different structural components

    Mother and Daughter Carrying of the Same Pathogenic Variant in FGFR2 with Discordant Phenotype

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    Craniosynostosis are a heterogeneous group of genetic conditions characterized by the premature fusion of the skull bones. The most common forms of craniosynostosis are Crouzon, Apert and Pfeiffer syndromes. They differ from each other in various additional clinical manifestations, e.g., syndactyly is typical of Apert and rare in Pfeiffer syndrome. Their inheritance is autosomal dominant with incomplete penetrance and one of the main genes responsible for these syndromes is FGFR2, mapped on chromosome 10, encoding fibroblast growth factor receptor 2. We report an FGFR2 gene variant in a mother and daughter who present with different clinical features of Crouzon syndrome. The daughter is more severely affected than her mother, as also verified by a careful study of the face and oral cavity. The c.1032G&gt;A transition in exon 8, already reported as a synonymous p.Ala344 = variant in Crouzon patients, also activates a new donor splice site leading to the loss of 51 nucleotides and the in-frame removal of 17 amino acids. We observed lower FGFR2 transcriptional and translational levels in the daughter compared to the mother and healthy controls. A preliminary functional assay and a molecular modeling added further details to explain the discordant phenotype of the two patients
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