340 research outputs found

    Fixation of genetic variation and optimization of gene expression: The speed of evolution in isolated lizard populations undergoing Reverse Island Syndrome

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    The ecological theory of island biogeography suggests that mainland populations should be more genetically divergent from those on large and distant islands rather than from those on small and close islets. Some island populations do not evolve in a linear way, but the process of divergence occurs more rapidly because they undergo a series of phenotypic changes, jointly known as the Island Syndrome. A special case is Reversed Island Syndrome (RIS), in which populations show drastic phenotypic changes both in body shape, skin colouration, age of sexual maturity, aggressiveness, and food intake rates. The populations showing the RIS were observed on islets nearby mainland and recently raised, and for this they are useful models to study the occurrence of rapid evolutionary change. We investigated the timing and mode of evolution of lizard populations adapted through selection on small islets. For our analyses, we used an ad hoc model system of three populations: wild-type lizards from the mainland and insular lizards from a big island (Capri, Italy), both Podarcis siculus siculus not affected by the syndrome, and a lizard population from islet (Scopolo) undergoing the RIS (called P. s. coerulea because of their melanism). The split time of the big (Capri) and small (Scopolo) islands was determined using geological events, like sea-level rises. To infer molecular evolution, we compared five complete mitochondrial genomes for each population to reconstruct the phylogeography and estimate the divergence time between island and mainland lizards. We found a lower mitochondrial mutation rate in Scopolo lizards despite the phenotypic changes achieved in approximately 8,000 years. Furthermore, transcriptome analyses showed significant differential gene expression between islet and mainland lizard populations, suggesting the key role of plasticity in these unpredictable environments

    Monitoring denitrification by means of pH and ORP in continuous-flow conventional activated sludge processes

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    Indirect signal analysis (pH, ORP and DO) are often used in monitoring and control of SBRs (Sequencing Batch Reactors), where operating conditions can be clearly identified during the various cyclic phases. Only few studies applied this methodology to control continuous flow plants, as it is much more difficult to identify operating conditions because of continually variable inflow characteristics. This work applied indirect signal analysis to control pre-denitrification in continuous-flow activated sludge processes: (i) a laboratory-scale plant, fed with synthetic wastewater, simulating real municipal wastewater and (ii) a pilot-scale plant, fed with real sewage. Three different ranges of ORP values identify three operational conditions of the denitrification process. (1) ORP > 0 mV means that nitrates and/or nitrites are present, possibly due to a low C/N ratio. (2) –50 < ORP < –200 mV is typical of normal operating conditions, that is with a balanced C/N ratio. (3) ORP < –350 mV means that oxidized nitrogen load is too low or that C/N exceeds the stoichiometric ratio. The trend of pH, instead, points out if and how the process is evolving from one to another operating condition. The correlation between pH and ORP signals (as well as their derivatives) allows to restore normal operating conditions by acting on the internal recycle flow-rate. Improved denitrification process ensures lower effluent nitrate concentration, and reduce external carbon dosage to achieve stricter nitrogen limits

    Arachidonic Acid/ppara Enhancement of Ca2+-Regulated Exocytosis in Antral Mucous Cells of Guinea Pig

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    N is known to be the most limiting element for vegetation growth in temperate and boreal forests. The expected increases in global temperature are predicted to accelerate N mineralization, therefore incrementing N availability in the soil and affecting the soil C cycle as well. While there is an abundance of C data collected to fulfill the requirements for national GHG accounting, more limited information is available for soil N accumulation and storage in relation to forest categories and altitudinal gradients. The data collected by the second Italian National Forest Inventory, spanning a wide range of temperature and precipitation values (10° latitudinal range), represented a unique opportunity to calculate N content and C/N ratio of the different soil layers to a depth of 30 cm. Boosted Regression Tree (BRT) models were applied to investigate the main determinants of soil N distribution and C/N ratio. Forest category was shown to be the main explanatory factor of soil N variability in seven out of eight models, both for forest floor and mineral soil layers. Moreover latitude explained a larger share of variability than single climate variables. BRT models explained, on average, the 49% of the data variability, with the remaining fraction likely due to soil-related variables that were unaccounted for. Accurate estimations of N pools and their determinants in a climate change perspective are consequently required to predict the potential impact of their degradation on forest soil N pools

    GEANT4 : a simulation toolkit

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    Abstract Geant4 is a toolkit for simulating the passage of particles through matter. It includes a complete range of functionality including tracking, geometry, physics models and hits. The physics processes offered cover a comprehensive range, including electromagnetic, hadronic and optical processes, a large set of long-lived particles, materials and elements, over a wide energy range starting, in some cases, from 250 eV and extending in others to the TeV energy range. It has been designed and constructed to expose the physics models utilised, to handle complex geometries, and to enable its easy adaptation for optimal use in different sets of applications. The toolkit is the result of a worldwide collaboration of physicists and software engineers. It has been created exploiting software engineering and object-oriented technology and implemented in the C++ programming language. It has been used in applications in particle physics, nuclear physics, accelerator design, space engineering and medical physics. PACS: 07.05.Tp; 13; 2

    Optimal and Automated Deployment for Microservices

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    Microservices are highly modular and scalable Service Oriented Architectures. They underpin automated deployment practices like Continuous Deployment and Autoscaling. In this paper, we formalize these practices and show that automated deployment - proven undecidable in the general case - is algorithmically treatable for microservices. Our key assumption is that the configuration life-cycle of a microservice is split into two phases: (i) creation, which entails establishing initial connections with already available microservices, and (ii) subsequent binding/unbinding with other microservices. To illustrate the applicability of our approach, we implement an automatic optimal deployment tool and compute deployment plans for a realistic microservice architecture, modeled in the Abstract Behavioral Specification (ABS) language

    Isomorphisms of types in the presence of higher-order references (extended version)

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    We investigate the problem of type isomorphisms in the presence of higher-order references. We first introduce a finitary programming language with sum types and higher-order references, for which we build a fully abstract games model following the work of Abramsky, Honda and McCusker. Solving an open problem by Laurent, we show that two finitely branching arenas are isomorphic if and only if they are geometrically the same, up to renaming of moves (Laurent's forest isomorphism). We deduce from this an equational theory characterizing isomorphisms of types in our language. We show however that Laurent's conjecture does not hold on infinitely branching arenas, yielding new non-trivial type isomorphisms in a variant of our language with natural numbers

    GEANT4--a simulation toolkikt

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    Geant4 is a toolkit for simulating the passage of particles through matter. It includes a complete range of functionality including tracking, geometry, physics models and hits. The physics processes offered cover a comprehensive range, including electromagnetic, hadronic and optical processes, a large set of long-lived particles, materials and elements, over a wide energy range starting, in some cases, from 250 eV and extending in others to the TeV energy range. It has been designed and constructed to expose the physics models utilised, to handle complex geometries, and to enable its easy adaptation for optimal use in different sets of applications. The toolkit is the result of a worldwide collaboration of physicists and software engineers. It has been created exploiting software engineering and object-oriented technology and implemented in the C++ programming language. It has been used in applications in particle physics, nuclear physics, accelerator design, space engineering and medical physics

    Effectiveness and Safety of Transthoracic Ultrasound in Guiding Percutaneous Needle Biopsy in the Lung and Comparison vs. CT Scan in Assessing Morphology of Subpleural Consolidations

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    (1) Background: The aim of this study was to conduct a prospective analysis on the diagnostic accuracy of transthoracic ultrasound-guided percutaneous needle biopsy (TUS-PNB) for the histological assessment of peripheral lung lesions and to assess the performance of transthoracic ultrasound (TUS) examination vs. chest CT (gold standard) in the differentiation between malignant and benign peripheral lung lesions. (2) Methods: A total of 961 consecutive patients with subpleural pulmonary lesions were enrolled. All the patients received a CT scan with contrast; 762 patients underwent TUS-PTNB for suspicion of malignancy, and the remaining 199 enrolled patients underwent only TUS examination as a part of routine follow-up for known non-malignant subpleural consolidations. (3) Results: Among the 762 TUS-guided biopsies, there were 627 (82.28%) malignant lesions, 82 (10.76%) benign lesions, and 53 (6.96%) indeterminate lesions. The overall diagnostic accuracy was 93.04%. The rates of pneumothorax not requiring chest-tube insertion and self-limited hemoptysis were 0.79 and 0.26%, respectively. Patients were divided into two groups based on the benign or malignant nature of the subpleural consolidations. On TUS, both malignant and benign lesions showed mostly irregular margins and a hypoechoic pattern, but no differences were assessed in terms of sonographic margins and pattern between the two groups. There was poor agreement between TUS and chest CT in assessing air bronchograms and necrotic areas. The only finding in the detection of which TUS showed superiority compared to chest-CT was pleural effusion. (4) Conclusions: TUS-PNB was confirmed to be an effective and safe diagnostic method for peripheral pulmonary consolidation, but their sonographic pattern did not allow to rule out a malignant nature. A pre-operative evaluation on CT images, combined with the possibility of performing additional immunohistochemical and cytological investigations and the experience of the medical staff, may improve the diagnostic yield of TUS-guided biopsies
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