The role of biotic interactions in shaping the distribution and abundance of species should be particularly pronounced in symbionts. Indeed, symbionts have a dual niche composed of traits of their individual hosts and the abiotic environment external to the host, and often combine active dispersal at finer scales with host-mediated dispersal at broader scales. The biotic complexity in the determinants of species distribution and abundance should be even more pronounced for hyper symbionts (symbionts of other symbionts).
View Article and Find Full Text PDFPurpose: To present a three-dimensional non-parametric method for detecting scleral asymmetry using corneoscleral topography data that are free of edge-effect artefacts.
Methods: The study included 88 participants aged 23 to 65 years (37.7±9.
: To present a novel design method for non-orthogonal lenses to reduce the problem of residual astigmatism in non-orthogonal, astigmatic eyes : A method to create spectacle trial lenses with non-orthogonal power axes was developed based on a novel optimised light ray-tracing algorithm rather than conventional lens design methods which could not fully eliminate spherical aberration. Using this method, three sets of refraction trial lenses were made with the angles between power axes of each set controlled at 80°, 70° and 60°, respectively. Within each set, the cylindrical power varied from -1.
View Article and Find Full Text PDFPurpose: To present a novel non-parametric algorithm for detecting the position of the human eye limbus in three dimensions and a new dynamic method for measuring the full 360° visible iris boundary known as white-to-white distance along the eye horizontal line.
Methods: The study included 88 participants aged 23 to 65 years (37.7±9.
A distinct population of Anteholosticha intermedia was isolated from soil in the Great Smoky Mountains of North Carolina, USA, and its morphology, morphogenesis and molecular phylogeny investigated by microscopic observations of live and protargol-prepared specimens and analyses of the sequence of small subunit (SSU) rDNA. Our population closely resembles the populations from Austria and Korea. Members of the genus Anteholosticha have been regarded as ontogenetically diverse, which is confirmed by the present work.
View Article and Find Full Text PDFPurpose: To investigate the prevalence of non-orthogonal astigmatism among normal and keratoconic Brazilian and Chinese populations.
Methods: Topography data were obtained using the Pentacam High Resolution (HR) system from 458 Brazilian (aged 35.6 ± 15.
The mechanical properties of an all-acrylate liquid crystal elastomer (LCE) with a glass transition of 14 ± 1 °C are reported. The highly nonlinear load curve has a characteristic shape associated with semi-soft elasticity (SSE). Conversely, measurements of the director orientation throughout tensile loading instead indicate a "mechanical-Fréedericksz" transition (MFT).
View Article and Find Full Text PDFPeritrichs are a major group of ciliates with worldwide distribution, and they play important roles in many habitats. Intrafamilial phylogeny of some peritrichs was investigated using information from three genes, which provided more robust interpretations than single-gene analyses. Sixty-seven new sequences including SSU rDNA, ITS1-5.
View Article and Find Full Text PDFEur J Protistol
October 2017
Biology is now turning toward a more integrative approach to research, distinguished by projects that depend on collaboration across hierarchical levels of organization or across disciplines. This trend is prompted by the need to solve complex, large-scale problems and includes disciplines that could be defined as integrative biodiversity. Integrative biodiversity of protists, including that of ciliates, is still partially in its infancy.
View Article and Find Full Text PDFThe colonial peritrich ciliate Epistylis anastatica (Linnaeus, 1767) was discovered living as an epibiont on Mesocyclops isabellae Dussart & Fernando, 1988 collected from a pond in Andhra Pradesh state, India. This is the first report of Epistylis on this host, and a description of its morphological characteristics is provided. The biomass of colonies of E.
View Article and Find Full Text PDFA new peritrichous ciliate, Cothurnia salina n. sp., collected from a brine pond of a salt factory in Yantai, China, was investigated based on live observations, silver staining method and molecular phylogenetic analysis.
View Article and Find Full Text PDFThe genera Lagenophrys Stein, 1852, Paralagenophrys Clamp, 1987, Clistolagenophrys Clamp, 1991, and Operculigera Kane, 1969 make up the family Lagenophryidae and, together, contain more than 80 species worldwide that live mainly as ectosymbionts of crustaceans. Lagenophryids are characterized by possession of a lorica, but the lorica aperture and the associated parts of the body differ between genera. Despite their widespread distribution, relatively few papers have been published on lagenophryids in recent years, and the present paper is intended to promote research on lagenophryids by providing an annotated checklist of all known species and a brief review of the family, including data of their geographic distribution and their hosts.
View Article and Find Full Text PDFPeritrichs are a major group of ciliates with worldwide distribution. Yet, its internal phylogeny remains unresolved owing to limited sampling. Additionally, ecological distributions of peritrichs are poorly known.
View Article and Find Full Text PDFHere we provide a brief review of the rare biosphere from the perspective of ciliates and other microbial eukaryotes. We trace research on rarity from its lack of much in-depth focus in morphological and Sanger sequencing projects, to its central importance in analyses using high throughput sequencing strategies. The problem that the rare biosphere is potentially comprised of mostly errors is then discussed in the light of asking community-comparative, novel-diversity, and ecosystem-functioning questions.
View Article and Find Full Text PDFPresbyopia, the age-related reduction in near vision acuity, is one of the leading issues facing the contact lens industry due to an increasingly ageing population and limitations associated with existing designs. A plastic-based liquid crystal contact lens is described which is designed to allow switchable vision correction. The device is characterized by low operating voltages (<5V(rms)) and has curvatures suitable for placement upon the cornea.
View Article and Find Full Text PDFVorticella includes more than 100 currently recognized species and represents one of the most taxonomically challenging genera of ciliates. Molecular phylogenetic analysis of Vorticella has been performed so far with only sequences coding for small subunit ribosomal RNA (SSU rRNA); only a few of its species have been investigated using other genetic markers owing to a lack of similar sequences for comparison. Consequently, phylogenetic relationships within the genus remain unclear, and molecular discrimination between morphospecies is often difficult because most regions of the SSU rRNA gene are too highly conserved to be helpful.
View Article and Find Full Text PDFTwo new species of the taxonomically confused genus Amphisiella were isolated from brackish-water habitats in southern China, and their morphology and morphogenesis were investigated. The genes coding for small subunit (SSU) rRNA were sequenced in each species and included in a phylogenetic analysis with all data available from nominal species of Amphisiella and related hypotrichs. Both new species are diagnosed by an elongate body shape, yellow-brown/grey-brown cell color, one kind of cortical granule, and two macronuclear nodules.
View Article and Find Full Text PDFThe stomatogenesis of peritrich ciliates is an important developmental process but has been studied relatively little for such a large, diverse taxon. Complex oral structures and an inability of staining techniques to reveal them clearly have been the major factors hindering investigation of this process. In the present study, an improved method of staining with protargol was used to investigate the entire process of stomatogenesis in a large, colonial species of peritrich, Pseudepistylis songi, and to compare it to descriptions of stomatogenesis in several other species.
View Article and Find Full Text PDFA multigrid computational model has been developed to assess the performance of refractive liquid crystal lenses, which is up to 40 times faster than previous techniques. Using this model, the optimum geometries producing an ideal parabolic voltage distribution were deduced for refractive liquid crystal lenses with diameters from 1 to 9 mm. The ratio of insulation thickness to lens diameter was determined to be 1:2 for small diameter lenses, tending to 1:3 for larger lenses.
View Article and Find Full Text PDFJ Eukaryot Microbiol
August 2012
We studied the morphology and molecular phylogeny of Myoschiston duplicatum, a peritrich ciliate that has been recorded as an epibiont of crustaceans, but which we also identified on marine algae from Korea. The important morphological characteristics revealed by silver staining of Myoschiston species have not been described because they are rarely collected. Using morphological methods, we redescribed the type species of the genus, Myoschiston duplicatum, and provided an improved diagnosis of Myoschiston.
View Article and Find Full Text PDFRecent phylogenetic analyses of the peritrich genus Vorticella have suggested that it might be paraphyletic, with one Vorticella species - Vorticella microstoma grouping with the swimming peritrichs Astylozoon and Opisthonecta in a distant clade. These results were based on very limited taxon sampling and thus could not be accepted as conclusive evidence for revising the generic classification. We tested paraphyly of the genus Vorticella by making a new analysis with a broad range of samples from three continents that yielded 52 new sequences of the gene coding for small subunit rRNA.
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