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The genus Nagiella was studied using morphological and DNA barcode data. Nagiella bispina sp. nov. is described as a new species, and N. hortulatoides Munroe is recorded in China for the first time. The diagnosis of this genus is revised, and the genitalia description of N. quadrimaculalis (Kollar and Redtenbacher) and N. inferior (Hampson) are given in English for the first time. Nosophora incomitata (Swinhoe) stat. rev. is removed from the synonym of N. quadrimaculalis. Photographs of the habitus and genitalia as well as COI DNA Barcode data of these four species are provided. [ABSTRACT FROM AUTHOR]

Rhinomirini (Insecta: Heteroptera: Miridae: Cylapinae) is a heterogeneous tribe of uncertain systematic position. We provide a phylogenetic analysis of this tribe based on morphological characters and molecular markers. Monophyly of the tribe was not supported by our findings. The Rhinocylapus complex and Rhinomiriella complex are transferred to Fulviini. Rhinomirini are restricted to the Rhinomiris complex. The record of Rhinomirini in Australia is considered dubious. The genera Punctifulvius and Yamatofulvus are transferred to the Rhinocylapus complex. The Rhinocylapus complex is recorded from Australia for the first time, with four new species: Mycetocylapus alexeyi sp. nov. , Punctifulvius austellus sp. nov. , Punctifulvius aquilonius sp. nov. and Rhinocylapoides valentinae sp. nov. The Philippine species Mycetocylapus major is synonymized with Mycetocylapus minor. The Australian species Rhinomiriella tuberculata is redescribed, and females of this species are described for the first time. Rhinomiriella aidani sp. nov. is described as new to science. The female genitalia of Proamblia elongata , Rhinocylapidius velocipidoides and Rhinomiris conspersus and the male genitalia of Rhinomiris conspersus and Rhinomiridius aethiopicus are illustrated and discussed. Sexual dimorphism in the Rhinocylapus complex and wing modifications in Cylapinae are discussed. [ABSTRACT FROM AUTHOR]

In this work a procedure is proposed to determine an optimal distribution of b-values in diffusion MRI measu-rements. The optimization procedure uses a method of Maximum Likelihood Estimation which can operate on any given number of b-values, values of the diffusion coefficients (ADC) and measurement noise strengths. Optimal b-values are calculated for white and gray brain matter. An optimi-zation for more than one ADC is demonstrated using multiple target values.

Five species of the genus Herpetogramma in China are studied with morphological and DNA barcode data. Herpetogramma biconvexa Wan, Lu & Du, sp. nov., H. longispina Wan, Lu & Du, sp. nov., and H. brachyacantha Wan, Lu & Du, sp. nov. are described as new. Herpetogramma rudis (Warren) and H. magna (Butler) are newly diagnosed. Photographs of the habitus and genitalia of these five species are provided. [ABSTRACT FROM AUTHOR]

Weed emergence models have the potential to be important tools for automating weed control actions; however, producing the necessary data (e.g., seedling counts) is time consuming and tedious. If similar weed emergence models could be created by deriving emergence data from images rather than physical counts, the amount of generated data could be increased to create more robust models. In this research, repeat RGB images taken throughout the emergence period of Raphanus raphanistrum L. and Senna obtusifolia (L.) Irwin and Barneby underwent pixel-based spectral classification. Relative cumulative pixels generated by the weed of interest over time were used to model emergence patterns. The models that were derived from cumulative pixel data were validated with the relative emergence of true seedling counts. The cumulative pixel model for R. raphanistrum and S. obtusifolia accounted for 92% of the variation in relative emergence of true counts. The results demonstrate that a simple image analysis approach based on time-dependent changes in weed cover can be used to generate weed emergence predictive models equivalent to those produced based on seedling counts. This process will help researchers working on weed emergence models, providing a new low-cost and technologically simple tool for data collection.

Walnut ( Juglans regia L.) is known as "hodu" in South Korea. It is cultivated as a cash crop and an ornamental plant across South Korea. Walnut anthracnose is one of the main limiting factors for walnut production. In June 2022, severe anthracnose was observed in several walnut fields in Gimcheon, South Korea. The disease incidence was ~35% and symptoms on affected fruits consist of necrotic and circular lesions with or without conidial mass. Six pure isolates with similar morphological characteristics were obtained from the tissue of six affected fruits. Diseased tissues were cut into 3-to-4 mm2 pieces, surface sterilized by 1% sodium hypochlorite (NaOCl) for 2 minutes, and washed three times in sterile distilled water, then dried by blotting. Four pieces/plates were placed onto potato dextrose agar (PDA; Difco Becton Dickinson) and incubated at 25°C in the dark for 2-3 days. To obtain pure isolates, hyphal tips were transferred onto fresh PDA. The colonies of all isolates on the PDA were light gray to pinkish on the upper side and pink to vinaceous on the reverse after 7 days of incubation at 25°C in the dark. The conidia were hyaline, fusiform, aseptate, and 11.3 to 20.1 µm × 3.6 to 6.9 µm (n =100). Appressoria were single, cylendrical, smooth-walled, dark brown, and 8.1 to 14.3 × 5.4 to 10.5 μm (n =30). The morphological characteristics of the isolates were comparable with those of Colletotrichum orientalis (Chen et al. 2022). Three isolates (WN23, WN28 and WN30P) were selected based on morphological characteristics for molecular identification. The beta-tubulin (TUB2), actin (ACT), chitin synthase 1 (CHS-1), and histone 3 (HIS3) genes of selected isolates were amplified and sequenced using the primers Bt2a/Bt2b, ACT512F/ACT783R, CHS-79F/CHS-345R and CYLH3F + CYLH3R, respectively (Damm et al. 2012). The resulting consensus sequences of each gene were deposited in GenBank with the accession numbers (TUB2: LC742910 to LC742912; CHS-1: LC742916 to LC742918; ACT: LC742919 to LC742921, HIS3: LC742922 to LC742924). The constructed maximum likelihood tree based on TUB2, ACT, CHS-1, and HIS3 sequence data revealed that the three isolates formed a clade with C . orientalis reference strain CBS 128532 (ex-type). The pathogenicity of two representative isolates (WN28 and WN30P) was confirmed on healthy, surface-sterilized, and detached walnut fruits. Both wounded and nonwounded fruits (10/isolate) were inoculated with the conidial suspension (106 spores/ml). The wounded and unwounded control fruits were inoculated with sterile distilled water. All the fruits (inoculated and control) were incubated in containers at 25°C with a 12-h/12-h light/dark cycle. This experiment was repeated twice. Necrotic lesions were observed in all inoculated wounded fruits, while unwounded and control fruits remained asymptomatic. The pathogen was re-isolated from inoculated fruits and identified as C. orientalis by morphological characteristics and ITS and TUB2 sequences. Damm et al. (2012) has identified C . fioriniae as species belongs to two well separated clades. However, Chen et al. (2022) split the C . fiorini ae species into two species, with the new species called C . orientalis , as a causal agent of apple bitter rot. In previous studies, C . fioriniae has been reported as a causal of walnut anthracnose (Luongo et al. 2021; Zhu et al. 2015; Varjas et al. 2019). To our knowledge, this is the first report of C . orientalis as the causal agent of walnut anthracnose in South Korea. Since this disease reduces the commercial value and quality of walnut fruits, effective management practices should be developed to deal with C . orientalis .

Schistosoma mansoni is one of the three main causative agents of human schistosomiasis, a major health problem with a vast socio-economic impact. Recent advances in the proteomic analysis of schistosomes have revealed that peptidases are the main virulence factors involved in the pathogenesis of this disease. In this context, evolutionary studies can be applied to identify peptidase families that have been expanded in genomes over time in response to different selection pressures. Using a phylogenomic approach, we searched for expanded endopeptidase families in the S. mansoni predicted proteome with the aim of contributing to the knowledge of such enzymes as potential therapeutic targets. We found three endopeptidase families that comprise leishmanolysins (metallopeptidase M8 family), cercarial elastases (serine peptidase S1 family) and cathepsin D proteins (aspartic peptidase A1 family). Our results suggest that the Schistosoma members of these families originated from successive gene duplication events in the parasite lineage after its diversification from other metazoans. Overall, critical residues are conserved among the duplicated genes/proteins. Furthermore, each protein family displays a distinct evolutionary history. Altogether, this work provides an evolutionary view of three S. mansoni peptidase families, which allows for a deeper understanding of the genomic complexity and lineage-specific adaptations potentially related to the parasitic lifestyle.

We present original average-case results on the performance of the Ford-Fulkerson maxflow algorithm on grid graphs (sparse) and random geometric graphs (dense). The analysis technique combines experiments with probability generating functions, stochastic context free grammars and an application of the maximum likelihood principle enabling us to make statements about the performance, where a purely theoretical approach has little chance of success. The methods lends itself to automation allowing us to study more variations of the Ford-Fulkerson maxflow algorithm with different graph search strategies and several elementary operations. A simple depth-first search enhanced with random iterators provides the best performance on grid graphs. For random geometric graphs a simple priority-first search with a maximum-capacity heuristic provides the best performance. Notable is the observation that randomization improves the performance even when the inputs are created from a random process. [ABSTRACT FROM AUTHOR]

Strong earthquake events often result in liquefaction-induced ground movements such as settlements and lateral spreads that are a major cause of damage to buildings, bridges, and lifelines. This paper focuses on the subject of liquefaction-induced lateral spreads. Case histories with detailed cone penetration test (CPT) data are derived from the 2010–2011 Canterbury, New Zealand earthquake sequence and used to examine an existing empirical model for liquefaction-induced lateral spreads. The results confirmed the existence of a substantial discrepancy between the predicted and observed lateral spreads, indicating a need for improved models that consider uncertainties in the input parameters. Using a maximum likelihood analysis of the derived case histories, a new empirical probabilistic model was developed for the estimation of lateral spreads in the Christchurch, New Zealand area. Emphasis is placed on assessing the probability of exceedance of limiting displacements for design against the threat of lateral spreads. The new CPT-based probabilistic model with detailed formulations is presented along with an illustrative example. The limitations of the model are discussed. [ABSTRACT FROM AUTHOR]

Abstract: Folding and unfolding rates for the ultrafast folding villin subdomain were determined from a photon-by-photon analysis of fluorescence trajectories in single molecule FRET experiments. One of the obstacles to measuring fast kinetics in single molecule fluorescence experiments is blinking of the fluorophores on a timescale that is not well separated from the process of interest. By incorporating acceptor blinking into a two-state kinetics model, we show that it is possible to extract accurate rate coefficients on the microsecond time scale for folding and unfolding using the maximum likelihood method of Gopich and Szabo. This method yields the most likely parameters of a given model that can reproduce the observed photon trajectories. The extracted parameters agree with both the decay rate of the donor–acceptor cross correlation function and the results of ensemble equilibrium and kinetic experiments using nanosecond laser temperature jump. [Copyright &y& Elsevier]

We took a two-tiered approach to test monophyly of Nelsonioideae and place the group within Lamiales, and to deter-mine relationships among taxa within the group. Phylogenetic analysis of a molecular dataset (ndhF+trnL-F) for a broad sample of Lamiales supports monophyly of Nelsonioideae and places the clade with strong support as sister to a lineage composed of all other plants treated as Acanthaceae (Avicennia, Thunbergioideae, Acanthoideae). We propose to treat this entire group as Acanthaceae s.l. and hypothesize that indurate, explosively dehiscent capsules are a synapomorphy for the family, albeit with autapomorphic fruit types in Avicennia and Mendoncia. These results further support monophyly of family-level groups that have emerged from recent studies of Lamiales but are largely unsuccessful in resolving relationships among these groups, as also encountered by other workers. Our results contradict some aspects of relationships that have seemed resolved by earlier studies, notably among Byblidaceae, Scrophulariaceae, Thomandersia, and other Lamiales. Among Nelsonioideae, analysis of sequence data from rapidly evolving genie regions (trnS-G, ndhF-rp132+rp132-trnL(UAG), nrlTS) and a larger sample of nelso-nioids (i.e., all genera and multiple taxa to represent the diversity of species-rich genera) indicates that Nelsonia and Elytraria are monophyletic with strong support, but with only moderate support for Nelsonia as the first branching clade and Elytraria sister to the remaining nelsonioids. An African clade comprising monospecific Saintpauliopsis sister to Anisosepalum (two of three species sampled) is sister to a clade that includes all sampled members of pantropical Staurogyne plus New World Gynocraterium and Asian Ophiorrhiziphyllon. Gynocraterium is sister to all sampled members of New World Staurogyne; this last clade is sister to a clade comprising the other sampled Staurogyne plus Ophiorrhiziphyllon, which is nested among Asian Staurogyne. The taxonomic implications of these patterns of relationship are discussed. Our results suggest that Nelsonioideae have a complex history of inter-continental dispersals compared to other lineages of Acanthaceae of similar to much larger size in terms of number of species, making it an interesting group for biogeographic study. [ABSTRACT FROM AUTHOR]

Background: Schistosoma mansoni is one of the causative agents of schistosomiasis, a neglected tropical disease that affects about 237 million people worldwide. Despite recent efforts, we still lack a general understanding of the relevant host-parasite interactions, and the possible treatments are limited by the emergence of resistant strains and the absence of a vaccine. The S. mansoni genome was completely sequenced and still under continuous annotation. Nevertheless, more than 45% of the encoded proteins remain without experimental characterization or even functional prediction. To improve our knowledge regarding the biology of this parasite, we conducted a proteome-wide evolutionary analysis to provide a broad view of the S. mansoni's proteome evolution and to improve its functional annotation. Results: Using a phylogenomic approach, we reconstructed the S. mansoni phylome, which comprises the evolutionary histories of all parasite proteins and their homologs across 12 other organisms. The analysis of a total of 7,964 phylogenies allowed a deeper understanding of genomic complexity and evolutionary adaptations to a parasitic lifestyle. In particular, the identification of lineage-specific gene duplications pointed to the diversification of several protein families that are relevant for host-parasite interaction, including proteases, tetraspanins, fucosyltransferases, venom allergen-like proteins, and tegumental-allergen-like proteins. In addition to the evolutionary knowledge, the phylome data enabled us to automatically re-annotate 3,451 proteins through a phylogenetic-based approach rather than solely sequence similarity searches. To allow further exploitation of this valuable data, all information has been made available at PhylomeDB (http://www.phylomedb.org). Conclusions: In this study, we used an evolutionary approach to assess S. mansoni parasite biology, improve genome/proteome functional annotation, and provide insights into host-parasite interactions. Taking advantage of a proteome-wide perspective rather than focusing on individual proteins, we identified that this parasite has experienced specific gene duplication events, particularly affecting genes that are potentially related to the parasitic lifestyle. These innovations may be related to the mechanisms that protect S. mansoni against host immune responses being important adaptations for the parasite survival in a potentially hostile environment. Continuing this work, a comparative analysis involving genomic, transcriptomic, and proteomic data from other helminth parasites, other parasites, and vectors will supply more information regarding parasite's biology as well as host-parasite interactions. [ABSTRACT FROM AUTHOR]

Abstract: X-ray polarimetry has the potential to make key-contributions to our understanding of galactic compact objects like binary black hole systems and neutron stars, and extragalactic objects like active galactic nuclei, blazars, and Gamma-Ray Bursts. Furthermore, several particle astrophysics topics can be addressed including uniquely sensitive tests of Lorentz invariance. In the energy range from 10keV to several MeV, Compton polarimeters achieve the best performance. In this paper we evaluate the benefit that comes from using the azimuthal and polar angles of the Compton scattered photons in the analysis, rather than using the azimuthal scattering angles alone. We study the case of an ideal Compton polarimeter and show that a Maximum Likelihood analysis which uses the two scattering angles lowers the Minimum Detectable Polarization (MDP) by ≈20% compared to a standard analysis based on the azimuthal scattering angles alone. The accuracies with which the polarization fraction and the polarization direction can be measured improve by a similar amount. We conclude by discussing potential applications of Maximum Likelihood analysis methods for various polarimeter experiments. [Copyright &y& Elsevier]

This study attempted to accurately segment the mammographic masses and distinguish malignant from benign tumors. An adaptive region growing algorithm with hybrid assessment function combined with maximum likelihood analysis and maximum gradient analysis was developed in this paper. In order to accommodate different situations of masses, the likelihood and the edge gradients of segmented masses were weighted adaptively by the use of information entropy. 106 benign and 110 malignant tumors were included in this study. We found that the proposed algorithm obtained segmentation contour more accurately and delineated the tumor body as well as tumor peripheral regions covering typical mass boundaries and some spiculation patterns. Then the segmented results were evaluated by the classification accuracy. 42 features including age, intensity, shape and texture were extracted from each segmented mass and support vector machine (SVM) was used as a classifier. The classification accuracy was evaluated using the area ( Az) under the receiver operating characteristic (ROC) curve. It was found that the maximum likelihood analysis achieved an Az value of 0.835, the maximum gradient analysis got an Az value of 0.932 and the hybrid assessment function performed the best classification result where the value of Az was 0.948. In addition, compared with traditional region growing algorithm, our proposed algorithm is more adaptive and provides a better performance for future works. [ABSTRACT FROM AUTHOR]

Abstract: VNTRs are able to discriminate among closely related isolates of recently emerged clonal pathogens, including Yersinia pestis the etiologic agent of plague, because of their great diversity. Diversity is driven largely by mutation but little is known about VNTR mutation rates, factors affecting mutation rates, or the mutational mechanisms. The molecular epidemiological utility of VNTRs will be greatly enhanced when this foundational knowledge is available. Here, we measure mutation rates for 43 VNTR loci in Y. pestis using an in vitro generated population encompassing ∼96,000 generations. We estimate the combined 43-locus rate and individual rates for 14 loci. A comparison of Y. pestis and Escherichia coli O157:H7 VNTR mutation rates and products revealed a similar relationship between diversity and mutation rate in these two species. Likewise, the relationship between repeat copy number and mutation rate is nearly identical between these species, suggesting a generalized relationship that may be applicable to other species. The single- versus multiple-repeat mutation ratios and the insertion versus deletion mutation ratios were also similar, providing support for a general model for the mutations associated with VNTRs. Finally, we use two small sets of Y. pestis isolates to show how this general model and our estimated mutation rates can be used to compare alternate phylogenies, and to evaluate the significance of genotype matches, near-matches, and mismatches found in empirical comparisons with a reference database. [Copyright &y& Elsevier]

Our objective was to determine how varied is the response of C cycling to temperature and irradiance in tundra vegetation. We used a large chamber to measure C exchange at 23 locations within a small arctic catchment in Alaska during summer 2003 and 2004. At each location, we determined light response curves of C exchange using shade cloths, twice during a growing season. We used data to fit a simple photosynthesis-irradiance, respiration-temperature model, with four parameters. We used a maximum likelihood technique to determine the acceptable parameter space for each light curve, given measurement uncertainty. We then explored which sites and time periods had parameter sets in common—an indication of functional similarity. We found that seven distinct parameter sets were required to explain observed C flux responses to temperature and light variation at all sites and time periods. The variation in estimated maximum photosynthetic rate ( P max) was strongly correlated with measurements of site leaf area index (LAI). The behavior of tussock tundra sites, the dominant vegetation of arctic tundra, could largely be described with a single parameter set, with a P max of 9.7 μmol m−2 s−1. Tussock tundra sites had, correspondingly, similar LAI (mean = 0.66). Non-tussock sites (for example, sedge and shrub tundras) had larger spatial and temporal variations in both C dynamic parameters ( P max varying from 9.7–25.7 μmol m−2 s−1) and LAI (0.6–2.0). There were no clear relationships between dominant non-tussock vegetation types and a particular parameter set. Our results suggest that C dynamics of the acidic tussock tundra slopes and hilltops in northern Alaska are relatively simply described during the peak growing season. However, the foot-slopes and water tracks have more variable patterns of LAI and C exchange, not simply related to the dominant vegetation type. [ABSTRACT FROM AUTHOR]

Abstract: Pipe rehabilitation liners are often installed in host pipes that lie below the water table. As such, they are subjected to external hydrostatic pressure. The external pressure leads to early deformation in the liners, which could ultimately lead to its failing or buckling before its expected service lifetime is achieved. Experiments involving long term buckling behavior of liners are typically accelerated lifetime testing procedures. In an accelerated testing procedure involving type I censoring a liner is often subjected to a constant external hydrostatic pressure and observed until it fails or for a certain time, t whichever occurs first. Liners that do not fail at time t are deemed censored observations. While a constant pressure is convenient to use in experimental situations, in reality pressure fluctuates under soil conditions over time depending on the water table. It is, therefore, desirable to study and compare accelerated life testing models under variable and constant pressure. Statistical analysis of data on accelerated time till buckling is based on the maximum likelihood procedure for censored or uncensored observations. It is known that maximum likelihood estimates of model parameters are asymptotically (for very large samples) unbiased and normally distributed. In practice, however, it is important to determine the applicability of these asymptotic assumptions for relatively small samples with censored observations under constant and variable pressure. In this study, the accelerated Weibull model for time till buckling under constant pressure is extended to variable pressure and the applicability of the model is investigated by simulation for different sample sizes and different levels of censoring. Data were generated through computer simulation and estimates of parameters were obtained using the maximum likelihood and Newton–Raphson methods. Results on the statistical properties (concerning distribution and bias) of model parameter estimates were used to make inference about the applicability of the accelerated life testing procedure for relatively small censored samples encountered in practice. Expressions from the model are given for computing the probability of survival until a given time or the survival time for a given probability of survival. [Copyright &y& Elsevier]

Plagiochilasect.Vagaeis a large pantropical clade that is characterized morphologically by frequent terminal branching, vegetative distribution by propagules on the ventral surface of the leaves and a capsule wall with thickenings in all layers.Plagiochila corrugatafrom Brazil is characterized by strongly undulate, toothed leaf margins and represents the only known neotropical species of sect.Vagaewith unispiral elaters.Plagiochila cambuenafrom Madagascar is distinguished by the same features. Maximum likelihood and parsimony analyses of 38 nrDNA ITS sequences ofPlagiochilarevealP. corrugataandP. cambuenain a weakly (ML) to well (MP) supported monophyletic lineage withinP. sect. Vagae. As an outcome of the morphological and molecular investigation,P. cambuenais relegated to the synonymy ofP. corrugata. Plagiochila corrugatais placed in aVagae-subclade with 11 further American species. The range ofP. corrugatacan be ascribed to long-range dispersal from the Neotropics rather than a Gondwanan distribution. Species from tropical Asia and Africa are placed at the base of theVagaeclade. Branch length withinP. sect. Vagaepoints to a sudden radiation. © 2004 The Linnean Society of London,Botanical Journal of the Linnean Society, 2004,146, 469–481. [ABSTRACT FROM AUTHOR]

In vertebrates, a large proportion of genes is organized in gene families. Paralogous gene groups generated by gene duplication are related by homology, high degree of sequence identity and similar structural architecture of their products. Aspartic proteinases form a widely distributed protein superfamily including cathepsins, pepsins, renin and napsin. In the present study, the nucleotide sequences coding for various pepsins in 30 vertebrate species have been used to derive a gene phylogeny. Gene duplication and losses have been inferred from a reconciled tree, reconstructed by combining information from gene tree and species tree. Our findings based on the results of the relative rate ratio test and maximum likelihood analysis suggest that each round of gene duplication is characterized by adaptive evolution, although instances of evolution under positive selection have been found also long after divergence of gene families. The results of functional divergence analysis provided statistical evidence for shifted evolutionary rate after gene duplication. [Copyright &y& Elsevier]

A generalization of the approach of Brockhoff and Skovgaard [Food Quality & Preference, 5 (1994), 215] is given. The emphasis is on univariate assessor performance in sensory profiling. Statistical significance tests for difference between assessors of scaling, variability and sensitivity will be given. A test for disagreement effect is also presented. In addition the approach will provide individual scaling, variability, disagreement and sensitivity values, that can be used for subsequent tabulation, plotting and statistical analysis. The method of maximum likelihood is used throughout and all computations are implemented in a SAS® Macro PANMODEL that is available via the author''s homepage: http://www.dina.kvl.dk/∼per. [Copyright &y& Elsevier]

In experimental studies involving accelerated time until failure, each specimen is usually tested until failure or a given time t whichever occurs first. In analyzing such data, the conventional method used is least squares regression. The recommendation (ASTM D2992) is to include non-failed observations (censored data) as failures in establishing the regression line. Such an approach could lead to a serious error in prediction. To remedy this situation, we recommend instead a maximum likelihood approach in which non-failed observations are incorporated as censored and not as failed observations in the analysis. We compare the two methods of analyses using data on accelerated time until buckling of cured-in-place plastic liners. [Copyright &y& Elsevier]

Procedures for performing cladistic analyses can provide powerful tools for understanding the evolution of neuropeptide and polypeptide hormone coding genes. These analyses can be done on either amino acid data sets or nucleotide data sets and can utilize several different algorithms that are dependent on distinct sets of operating assumptions and constraints. In some cases, the results of these analyses can be used to gauge phylogenetic relationships between taxa. Selecting the proper cladistic analysis strategy is dependent on the taxonomic level of analysis and the rate of evolution within the orthologous genes being evaluated. For example, previous studies have shown that the amino acid sequence of proopiomelanocortin (POMC), the common precursor for the melanocortins and β-endorphin, can be used to resolve phylogenetic relationships at the class and order level. This study tested the hypothesis that POMC sequences could be used to resolve phylogenetic relationships at the family taxonomic level. Cladistic analyses were performed on amphibian POMC sequences characterized from the marine toad, Bufo marinus (family Bufonidae; this study), the spadefoot toad, Spea multiplicatus (family Pelobatidae), the African clawed frog, Xenopus laevis (family Pipidae) and the laughing frog, Rana ridibunda (family Ranidae). In these analyses the sequence of Australian lungfish POMC was used as the outgroup. The analyses were done at the amino acid level using the maximum parsimony algorithm and at the nucleotide level using the maximum likelihood algorithm. For the anuran POMC genes, analysis at the nucleotide level using the maximum likelihood algorithm generated a cladogram with higher bootstrap values than the maximum parsimony analysis of the POMC amino acid data set. For anuran POMC sequences, analysis of nucleotide sequences using the maximum likelihood algorithm would appear to be the preferred strategy for resolving phylogenetic relationships at the family taxonomic level. [Copyright &y& Elsevier]

Two opposing opinions concerning the generic differentiation of Amaryllidaceae subtribe Strumariinae two taxonomic opinions were published in the last decade. According to Müller-Doblies and Müller-Doblies (1985, 1994) the Strumariinae includes eight genera, among them Hessea, Namaquanula, and Dewinterella. Snijman (1991) described the new genus Kamiesbergia and accepted Namaquanula (1992). Of the entire complex she recognized only Hessea (Snijman 1994). The section Myophila was simultaneously described as the genus Dewinterella by Müller-Doblies and Müller-Doblies. The possible phylogenetic relationships of eight species belonging to these taxa are estimated from the sequences of the ITS regions of the 18S-25S rDNA. Two species of Nerine are used as the outgroup. The sequences of these taxa are analyzed with maximum parsimony, distance, and maximum likelihood methods. In all phylogenetic reconstructions Namaquanula is confirmed to be an independant clade aside from all other six species of the Strumariinae. In this group Hessea and Dewinterella turn out to be sister groups. Hessea stenosiphon (subgenus Kamiesbergia) is the sister taxon of H. breviflora. [ABSTRACT FROM AUTHOR]

The void ratio limits and their range are mostly governed by their grain size, distribution, particle shape and fabric for cohesionless soils. For the purpose of developing a probability-based predictive model, a database, which consists of minimum and maximum void ratios, their range, as well as particle morphology (roundness, sphericity), size and distribution (mean grain size, fines content and coefficient of uniformity) parameters, is compiled. A set of predictive models, which use the combinations of C u , D 50 , FC, R, and S parameters, is proposed. The models with C u and/or D 50 , R and S, produce the most precise predictions. The probabilistic forward use of the proposed models is illustrated by a practical example. They are also presented in the form of deterministic chart solutions, illustrating the variation of in-situ void ratios for varying density states as functions of uniformity coefficient or mean grain size. • A database consisting of emax and emin, grain shape (R, S), size and distribution (D50, FC & Cu) parameters, is compiled. • Probability-based predictive models, which use the combinations of Cu, D50, FC, R, and S parameters are proposed. • Deterministic in-situ void ratio vs. Cu or D50 and DR chart solutions are presented. • The probabilistic forward use of the proposed models is illustrated with a practical example. [ABSTRACT FROM AUTHOR]