Search results for "PROCESSES"
showing 10 items of 3831 documents
Deep-Time Phylogenetic Clustering of Extinctions in an Evolutionarily Dynamic Clade (Early Jurassic Ammonites)
2012
7 pages; International audience; Conservation biologists and palaeontologists are increasingly investigating the phylogenetic distribution of extinctions and its evolutionary consequences. However, the dearth of palaeontological studies on that subject and the lack of methodological consensus hamper our understanding of that major evolutionary phenomenon. Here we address this issue by (i) reviewing the approaches used to quantify the phylogenetic selectivity of extinctions and extinction risks; (ii) investigating with a high-resolution dataset whether extinctions and survivals were phylogenetically clustered among early Pliensbachian (Early Jurassic) ammonites; (iii) exploring the phylogene…
PACo: a novel procrustes application to cophylogenetic analysis.
2013
We present Procrustean Approach to Cophylogeny (PACo), a novel statistical tool to test for congruence between phylogenetic trees, or between phylogenetic distance matrices of associated taxa. Unlike previous tests, PACo evaluates the dependence of one phylogeny upon the other. This makes it especially appropriate to test the classical coevolutionary model that assumes that parasites that spend part of their life in or on their hosts track the phylogeny of their hosts. The new method does not require fully resolved phylogenies and allows for multiple host-parasite associations. PACo produces a Procrustes superimposition plot enabling a graphical assessment of the fit of the parasite phyloge…
A Review of the Water Desalination Technologies
2021
Desalination is commonly adopted nowadays to overcome the freshwater scarcity in some areas of the world if brackish water or salt water is available. Different kinds of technologies have been proposed in the last century. In this paper, the state of the mainstream solutions is reported, showing the current commercial technologies like reverse osmosis (RO), Multi-Stages Flash desalination (MSF) and Multi-Effect Distillation (MED), and the new frontiers of the research with the aim of exploiting renewable sources such as wind, solar and biomass energy. In these cases, seawater treatment plants are the same as traditional ones, with the only difference being that they use a renewable energy s…
Interviews with Community Healthcare Registered Nurses in Norway: Examination Practices and Clinical Evaluation Processes
2021
Abstract Aim This study describes the examination practices and clinical evaluation processes that Registered Nurses in Norway perform in the community healthcare sector. Design A qualitative exploratory design. Methods Twenty interviews were conducted with Registered Nurses employed in the community healthcare sector in Norway. The data were analysed using a thematic analysis. Results We found four major themes: (1) evaluations are embedded in nurses’ daily work, (2) significance of a Registered Nurse's clinical competency, (3) different tasks require various roles and (4) access to resources and equipment. Registered Nurses possess several skills in a range of different examination techni…
Coping between crises: Early Triassic–early Jurassic bivalve diversity dynamics
2011
The Triassic is bounded by two of the most severe biotic crises, but nevertheless this time was, for bivalves, both a recovery and a diversification period, and a moment to fully exploit some of their evolutionary novelties. Just how and when this was achieved is analyzed in this paper, which covers Induan to Sinemurian bivalve diversity, based on a newly compiled database. Taxonomic diversity and ecospace dynamics are examined separately. Diversity and evolutionary rates were assessed, extinction selectivity was tested using a resampling algorithm, and cohort analysis was used to study extinction patterns. During the Early Triassic most bivalve genera were survivors from the Permian and th…
Taphonomy of insects in carbonates and amber
2004
Abstract The major taphonomic processes that control insect preservation in carbonate rocks (limestones, travertines and nodules) are biological: insect size and wingspan, degree of decomposition, presence of microbial mats, predation and scavenging; environmental: water surface tension, water temperature, density and salinity, current activity; and diagenetic: authigenic mineralisation, flattening, deformation, carbonisation. The major taphonomic processes that control the preservation of insects in fossil resins (amber and copal) are different, but can be considered under the same headings – biological: presence of resin producers, size and behaviour of insects; environmental: latitude, c…
Late Miocene turnover in the Spanish mammal record in relation to palaeoclimate and the Messinian Salinity Crisis
2006
Abstract The latest Miocene and earliest Pliocene is a period of marked changes in geography and climate in the circum-Mediterranean area. Its geographical situation gives Spain a key position, and its fossil mammal record reflects these important geographical and climatic changes particularly well. The Spanish mammal record shows a gradual change of composition towards the typical Pleistocene and recent fauna, marked by several extinction and dispersal events. These events have the effect that northern Eurasian elements increase, while taxa that locally go extinct may live on in tropical areas. Superposed on this large scale trend, there are some events of short lived incursions of animals…
Extracorporeal Shock Waves Increase Markers of Cellular Proliferation in Bronchial Epithelium and in Primary Bronchial Fibroblasts of COPD Patients
2020
Chronic obstructive pulmonary disease (COPD) is due to structural changes and narrowing of small airways and parenchymal destruction (loss of the alveolar attachment as a result of pulmonary emphysema), which all lead to airflow limitation. Extracorporeal shock waves (ESW) increase cell proliferation and differentiation of connective tissue fibroblasts. To date no studies are available on ESW treatment of human bronchial fibroblasts and epithelial cells from COPD and control subjects. We obtained primary bronchial fibroblasts from bronchial biopsies of 3 patients with mild/moderate COPD and 3 control smokers with normal lung function. 16HBE cells were also studied. Cells were treated with a…
Constraining effective rheology through parallel joint geodynamic inversion
2014
Abstract The dynamics of crust and lithosphere is to a large extent controlled by its effective viscosity. Unfortunately, extrapolation of laboratory experiments indicates that viscosity is likely to vary over many orders of magnitude. Additional methods are thus required to constrain the effective viscosity of the present-day lithosphere using more direct geophysical observations. Here we discuss a method, which couples 3D geodynamic models with observations (surface velocities and gravity anomalies) and with a Bayesian inversion scheme on massively parallel high performance computers. We illustrate that the basic principle of a joint geodynamic and gravity inversion works well with a simp…
Personality and reinforcement: An exploration using a maze-learning task
1995
A computerized maze learning task was investigated under control, reward and punishment, provided by differing financial reinforcement contingencies. The relationships between speed crossing the maze and anxiety and impulsivity personality traits were explored. Anxiety is hypothesized to reflect a behavioural inhibition system active in punishing environments; and impulsivity, to reflect an activation system active in rewarding environments. Of the measures of impulsivity taken, only one—venturesomeness from the I7—was associated significantly with increased maze crossing speed; this was found particularly in the reward condition and in males. Several anxiety variables were associated with …