is a small genus comprising five species of inoperculate discomycetes in the order Helotiales (Leotiomycetes) often recognizable by their bright yellowish-green colors and gregarious growth on wood. In this study, we describe five new species-, and -based on a combination of recent fieldwork and examination of previously collected fungarium specimens. We use an integrative taxonomic approach to support the distinction of new species, incorporating morphology and DNA sequence data with biogeography.
View Article and Find Full Text PDFas typically conceived is a genus of noticeable, bright yellow inoperculate discomycetes. This interpretation of the genus, however, is at odds with , the current name of the type species of the genus; furthermore, the genus has been interpreted as including the unusual species . By comparing morphological and molecular traits of species traditionally included in , we show that the genus is polyphyletic, with many "typical" members of the genus belonging instead in in Pezizellaceae.
View Article and Find Full Text PDFClosed cleistothecia-like ascomata have repeatedly evolved in non-related perithecioid and apothecioid lineages of lichenized and non-lichenized . The evolution of a closed, darkly pigmented ascoma that protects asci and ascospores is conceived as either an adaptation to harsh environmental conditions or a specialized dispersal strategy. Species with closed ascomata have mostly lost sterile hymenial elements (paraphyses) and the capacity to actively discharge ascospores.
View Article and Find Full Text PDFMathematical simulations using the bidomain model, which represents cardiac tissue as consisting of an intracellular and an extracellular space, are a key approach that can be used to improve understanding of heart conditions such as ischaemia. However, key inputs to these models, such as the bidomain conductivity values, are not known with any certainty. Since efforts are underway to measure these values, it would be useful to be able to quantify the effect on model outputs of uncertainty in these inputs, and also to determine, if possible, which are the most important values to focus on in experimental studies.
View Article and Find Full Text PDFAccurate values for the six cardiac bidomain conductivities are crucial for meaningful computational studies of conduction in cardiac tissue, and are yet to be determined by experimental means. Although previous studies have proposed an approach using a multi-electrode array to measure potentials, from which the conductivities can be determined, it has been found that the conductivities cannot be retrieved consistently when the noise in the potentials varies. This paper presents a protocol, which not only has been shown to retrieve the conductivities to a reasonable accuracy, but does so under the presence of a more appropriate additive Gaussian noise model, while using fewer computational resources.
View Article and Find Full Text PDFA second genus in Chlorociboriaceae is described here as Macroscopically distinctive, all species have bright yellow apothecia with several apothecial cups held on short branches at the tip of a long stipe. The genus is widely distributed across the Southern Hemisphere; the four new species described here include two from Chile ( , ) and one each from New Zealand ( ) and Australia ( ). They differ from species referred to , the only other genus in Chlorociboriaceae, in their terrestrial habitat and ascomata that are noticeably more hairy than the known species, most of which have apothecia with short, macroscopically indistinct hair-like elements.
View Article and Find Full Text PDFThe identification and proper naming of microfungi, in particular plant, animal and human pathogens, remains challenging. Molecular identification is becoming the default approach for many fungal groups, and environmental metabarcoding is contributing an increasing amount of sequence data documenting fungal diversity on a global scale. This includes lineages represented only by sequence data.
View Article and Find Full Text PDFMed Biol Eng Comput
December 2020
Modelling the electrical activity of the heart is an important tool for understanding electrical function in various diseases and conduction disorders. Clearly, for model results to be useful, it is necessary to have accurate inputs for the models, in particular the commonly used bidomain model. However, there are only three sets of four experimentally determined conductivity values for cardiac ventricular tissue and these are inconsistent, were measured around 40 years ago, often produce different results in simulations and do not fully represent the three-dimensional anisotropic nature of cardiac tissue.
View Article and Find Full Text PDFFungi in the class are ecologically diverse, including mycorrhizas, endophytes of roots and leaves, plant pathogens, aquatic and aero-aquatic hyphomycetes, mammalian pathogens, and saprobes. These fungi are commonly detected in cultures from diseased tissue and from environmental DNA extracts. The identification of specimens from such character-poor samples increasingly relies on DNA sequencing.
View Article and Find Full Text PDFTriblidiaceae (Rhytismatales) currently consists of two genera: and . is the type genus and is characterised by melanized apothecia that occur scattered or in small clusters on the substratum, cleistohymenial (opening in the mesohymenial phase), inamyloid thin-walled asci and hyaline muriform ascospores. Before this study, only the type species, , had DNA sequences in the NCBI GenBank.
View Article and Find Full Text PDFMathematical modelling is a useful technique to help elucidate the connection between non-transmural ischaemia and ST elevation and depression of the ECG. Generally, models represent non-transmural ischaemia using an ischaemic zone that extends from the endocardium partway to the epicardium. However, recent experimental work has suggested that ischaemia typically arises within the heart wall.
View Article and Find Full Text PDFThe new genus is proposed to accommodate a single species that was repeatedly collected on fallen wood in forests of New Zealand and was previously misidentified as a species. This monotypic genus belongs to , a recently erected family in . is differentiated from other by phragmospores that do not form conidia either in or outside the asci, an exciple of with hyphae widely spaced and strongly gelatinized (plectenchyma), and apically flexuous, partly helicoid paraphyses.
View Article and Find Full Text PDFComput Biol Med
November 2018
Solving the inverse problem of electrocardiology via the Method of Fundamental Solutions has been proposed previously. The advantage of this approach is that it is a meshless method, so it is far easier to implement numerically than many other approaches. However, determining the heart surface potential distribution is still an ill-posed problem and thus requires some form of Tikhonov regularisation to obtain the required distributions.
View Article and Find Full Text PDFAlthough computational studies are increasingly used to gain insight into diseases such as myocardial ischaemia, there is still considerable uncertainty about the values for many of the parameters in these studies. This is particularly true for the bidomain conductivity values that are used in normal tissue and, even more so, in ischaemic tissue, when modelling ischaemia. In this work, we extended a previous study that used a half-ellipsoidal model and a realistic model to study subendocardial ischaemia during the ST segment, so that we could simulate both early and late stage ischaemia.
View Article and Find Full Text PDFGlobal trade and the movement of people accelerate biological invasions by spreading species worldwide. Biosecurity measures seek to allow trade and passenger movements while preventing incursions that could lead to the establishment of unwanted pests, pathogens, and weeds. However, few data exist to evaluate whether changes in trade volumes, passenger arrivals, and biosecurity measures have altered rates of establishment of nonnative species over time.
View Article and Find Full Text PDFThere is considerable interest in simulating ischaemia in the ventricle and its effect on the electrocardiogram, because a better understanding of the connection between the two may lead to improvements in diagnosis of myocardial ischaemia. In this work we studied subendocardial ischaemia, in a simplified half-ellipsoidal bidomain model of a ventricle, and its effect on ST segment epicardial potential distributions (EPDs). We found that the EPD changed as the ischaemic depth increased, from a single minimum (min1) over the ischaemic region to a maximum (max) there, with min1 over the border of the region.
View Article and Find Full Text PDFHigh-throughput sequencing technologies using amplicon approaches have changed the way that studies investigating fungal distribution are undertaken. These powerful and time-efficient technologies have the potential for the first time to accurately map fungal distributions across landscapes or changes in diversity across ecological or biological gradients of interest. There is no requirement for a fungus to form a fruiting body to be detected, and both culturable and nonculturable organisms can be detected.
View Article and Find Full Text PDFReduced blood flow in the coronary arteries can lead to damaged heart tissue (myocardial ischaemia). Although one method for detecting myocardial ischaemia involves changes in the ST segment of the electrocardiogram, the relationship between these changes and subendocardial ischaemia is not fully understood. In this study, we modelled ST-segment epicardial potentials in a slab model of cardiac ventricular tissue, with a central ischaemic region, using the bidomain model, which considers conduction longitudinal, transverse and normal to the cardiac fibres.
View Article and Find Full Text PDFComput Methods Biomech Biomed Engin
August 2017
This study presents a comparison of semi-analytical and numerical solution techniques for solving the passive bidomain equation in simple tissue geometries containing a region of subendocardial ischaemia. When the semi-analytical solution is based on Fourier transforms, recovering the solution from the frequency domain via fast Fourier transforms imposes a periodic boundary condition on the solution of the partial differential equation. On the other hand, the numerical solution uses an insulation boundary condition.
View Article and Find Full Text PDFWe report on the molecular and morphological characterization of a novel type B trichothecene toxin-producing species (i.e. B clade) recovered from litter in a maize field near Wellington, New Zealand, which is described as Fusarium praegraminearum sp.
View Article and Find Full Text PDFNovel associations between plants and pathogens can have serious impacts on managed and natural ecosystems world-wide. The introduction of alien plants increases the potential for biogeographically novel plant-pathogen associations to arise when pathogens are transmitted from native to alien plant species and vice versa. We quantified biogeographically novel associations recorded in New Zealand over the last 150 yr between plant pathogens (fungi, oomycetes and plasmodiophorids) and vascular plants.
View Article and Find Full Text PDFParameters in modelling are not always known with absolute certainty. In epidemic modelling, this is true of many of the parameters. It is important for this uncertainty to be included in any model.
View Article and Find Full Text PDFRobust Generalised Cross-Validation was proposed recently as a method for determining near optimal regularisation parameters in inverse problems. It was introduced to overcome a problem with the regular Generalised Cross-Validation method in which the function that is minimised to obtain the regularisation parameter often has a broad, flat minimum, resulting in a poor estimate for the parameter. The robust method defines a new function to be minimised which has a narrower minimum, but at the expense of introducing a new parameter called the robustness parameter.
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